cgroup: superblock can't be released with active dentries
[firefly-linux-kernel-4.4.55.git] / drivers / tty / serial / crisv10.c
1 /*
2  * Serial port driver for the ETRAX 100LX chip
3  *
4  *    Copyright (C) 1998-2007  Axis Communications AB
5  *
6  *    Many, many authors. Based once upon a time on serial.c for 16x50.
7  *
8  */
9
10 static char *serial_version = "$Revision: 1.25 $";
11
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/signal.h>
15 #include <linux/sched.h>
16 #include <linux/timer.h>
17 #include <linux/interrupt.h>
18 #include <linux/tty.h>
19 #include <linux/tty_flip.h>
20 #include <linux/major.h>
21 #include <linux/string.h>
22 #include <linux/fcntl.h>
23 #include <linux/mm.h>
24 #include <linux/slab.h>
25 #include <linux/init.h>
26 #include <linux/kernel.h>
27 #include <linux/mutex.h>
28 #include <linux/bitops.h>
29 #include <linux/seq_file.h>
30 #include <linux/delay.h>
31 #include <linux/module.h>
32 #include <linux/uaccess.h>
33 #include <linux/io.h>
34
35 #include <asm/irq.h>
36 #include <asm/dma.h>
37
38 #include <arch/svinto.h>
39 #include <arch/system.h>
40
41 /* non-arch dependent serial structures are in linux/serial.h */
42 #include <linux/serial.h>
43 /* while we keep our own stuff (struct e100_serial) in a local .h file */
44 #include "crisv10.h"
45 #include <asm/fasttimer.h>
46 #include <arch/io_interface_mux.h>
47
48 #ifdef CONFIG_ETRAX_SERIAL_FAST_TIMER
49 #ifndef CONFIG_ETRAX_FAST_TIMER
50 #error "Enable FAST_TIMER to use SERIAL_FAST_TIMER"
51 #endif
52 #endif
53
54 #if defined(CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS) && \
55            (CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS == 0)
56 #error "RX_TIMEOUT_TICKS == 0 not allowed, use 1"
57 #endif
58
59 #if defined(CONFIG_ETRAX_RS485_ON_PA) && defined(CONFIG_ETRAX_RS485_ON_PORT_G)
60 #error "Disable either CONFIG_ETRAX_RS485_ON_PA or CONFIG_ETRAX_RS485_ON_PORT_G"
61 #endif
62
63 /*
64  * All of the compatibilty code so we can compile serial.c against
65  * older kernels is hidden in serial_compat.h
66  */
67 #if defined(LOCAL_HEADERS)
68 #include "serial_compat.h"
69 #endif
70
71 struct tty_driver *serial_driver;
72
73 /* number of characters left in xmit buffer before we ask for more */
74 #define WAKEUP_CHARS 256
75
76 //#define SERIAL_DEBUG_INTR
77 //#define SERIAL_DEBUG_OPEN
78 //#define SERIAL_DEBUG_FLOW
79 //#define SERIAL_DEBUG_DATA
80 //#define SERIAL_DEBUG_THROTTLE
81 //#define SERIAL_DEBUG_IO  /* Debug for Extra control and status pins */
82 //#define SERIAL_DEBUG_LINE 0 /* What serport we want to debug */
83
84 /* Enable this to use serial interrupts to handle when you
85    expect the first received event on the serial port to
86    be an error, break or similar. Used to be able to flash IRMA
87    from eLinux */
88 #define SERIAL_HANDLE_EARLY_ERRORS
89
90 /* Currently 16 descriptors x 128 bytes = 2048 bytes */
91 #define SERIAL_DESCR_BUF_SIZE 256
92
93 #define SERIAL_PRESCALE_BASE 3125000 /* 3.125MHz */
94 #define DEF_BAUD_BASE SERIAL_PRESCALE_BASE
95
96 /* We don't want to load the system with massive fast timer interrupt
97  * on high baudrates so limit it to 250 us (4kHz) */
98 #define MIN_FLUSH_TIME_USEC 250
99
100 /* Add an x here to log a lot of timer stuff */
101 #define TIMERD(x)
102 /* Debug details of interrupt handling */
103 #define DINTR1(x)  /* irq on/off, errors */
104 #define DINTR2(x)    /* tx and rx */
105 /* Debug flip buffer stuff */
106 #define DFLIP(x)
107 /* Debug flow control and overview of data flow */
108 #define DFLOW(x)
109 #define DBAUD(x)
110 #define DLOG_INT_TRIG(x)
111
112 //#define DEBUG_LOG_INCLUDED
113 #ifndef DEBUG_LOG_INCLUDED
114 #define DEBUG_LOG(line, string, value)
115 #else
116 struct debug_log_info
117 {
118         unsigned long time;
119         unsigned long timer_data;
120 //  int line;
121         const char *string;
122         int value;
123 };
124 #define DEBUG_LOG_SIZE 4096
125
126 struct debug_log_info debug_log[DEBUG_LOG_SIZE];
127 int debug_log_pos = 0;
128
129 #define DEBUG_LOG(_line, _string, _value) do { \
130   if ((_line) == SERIAL_DEBUG_LINE) {\
131     debug_log_func(_line, _string, _value); \
132   }\
133 }while(0)
134
135 void debug_log_func(int line, const char *string, int value)
136 {
137         if (debug_log_pos < DEBUG_LOG_SIZE) {
138                 debug_log[debug_log_pos].time = jiffies;
139                 debug_log[debug_log_pos].timer_data = *R_TIMER_DATA;
140 //    debug_log[debug_log_pos].line = line;
141                 debug_log[debug_log_pos].string = string;
142                 debug_log[debug_log_pos].value = value;
143                 debug_log_pos++;
144         }
145         /*printk(string, value);*/
146 }
147 #endif
148
149 #ifndef CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS
150 /* Default number of timer ticks before flushing rx fifo
151  * When using "little data, low latency applications: use 0
152  * When using "much data applications (PPP)" use ~5
153  */
154 #define CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS 5
155 #endif
156
157 unsigned long timer_data_to_ns(unsigned long timer_data);
158
159 static void change_speed(struct e100_serial *info);
160 static void rs_throttle(struct tty_struct * tty);
161 static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
162 static int rs_write(struct tty_struct *tty,
163                 const unsigned char *buf, int count);
164 #ifdef CONFIG_ETRAX_RS485
165 static int e100_write_rs485(struct tty_struct *tty,
166                 const unsigned char *buf, int count);
167 #endif
168 static int get_lsr_info(struct e100_serial *info, unsigned int *value);
169
170
171 #define DEF_BAUD 115200   /* 115.2 kbit/s */
172 #define STD_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
173 #define DEF_RX 0x20  /* or SERIAL_CTRL_W >> 8 */
174 /* Default value of tx_ctrl register: has txd(bit 7)=1 (idle) as default */
175 #define DEF_TX 0x80  /* or SERIAL_CTRL_B */
176
177 /* offsets from R_SERIALx_CTRL */
178
179 #define REG_DATA 0
180 #define REG_DATA_STATUS32 0 /* this is the 32 bit register R_SERIALx_READ */
181 #define REG_TR_DATA 0
182 #define REG_STATUS 1
183 #define REG_TR_CTRL 1
184 #define REG_REC_CTRL 2
185 #define REG_BAUD 3
186 #define REG_XOFF 4  /* this is a 32 bit register */
187
188 /* The bitfields are the same for all serial ports */
189 #define SER_RXD_MASK         IO_MASK(R_SERIAL0_STATUS, rxd)
190 #define SER_DATA_AVAIL_MASK  IO_MASK(R_SERIAL0_STATUS, data_avail)
191 #define SER_FRAMING_ERR_MASK IO_MASK(R_SERIAL0_STATUS, framing_err)
192 #define SER_PAR_ERR_MASK     IO_MASK(R_SERIAL0_STATUS, par_err)
193 #define SER_OVERRUN_MASK     IO_MASK(R_SERIAL0_STATUS, overrun)
194
195 #define SER_ERROR_MASK (SER_OVERRUN_MASK | SER_PAR_ERR_MASK | SER_FRAMING_ERR_MASK)
196
197 /* Values for info->errorcode */
198 #define ERRCODE_SET_BREAK    (TTY_BREAK)
199 #define ERRCODE_INSERT        0x100
200 #define ERRCODE_INSERT_BREAK (ERRCODE_INSERT | TTY_BREAK)
201
202 #define FORCE_EOP(info)  *R_SET_EOP = 1U << info->iseteop;
203
204 /*
205  * General note regarding the use of IO_* macros in this file:
206  *
207  * We will use the bits defined for DMA channel 6 when using various
208  * IO_* macros (e.g. IO_STATE, IO_MASK, IO_EXTRACT) and _assume_ they are
209  * the same for all channels (which of course they are).
210  *
211  * We will also use the bits defined for serial port 0 when writing commands
212  * to the different ports, as these bits too are the same for all ports.
213  */
214
215
216 /* Mask for the irqs possibly enabled in R_IRQ_MASK1_RD etc. */
217 static const unsigned long e100_ser_int_mask = 0
218 #ifdef CONFIG_ETRAX_SERIAL_PORT0
219 | IO_MASK(R_IRQ_MASK1_RD, ser0_data) | IO_MASK(R_IRQ_MASK1_RD, ser0_ready)
220 #endif
221 #ifdef CONFIG_ETRAX_SERIAL_PORT1
222 | IO_MASK(R_IRQ_MASK1_RD, ser1_data) | IO_MASK(R_IRQ_MASK1_RD, ser1_ready)
223 #endif
224 #ifdef CONFIG_ETRAX_SERIAL_PORT2
225 | IO_MASK(R_IRQ_MASK1_RD, ser2_data) | IO_MASK(R_IRQ_MASK1_RD, ser2_ready)
226 #endif
227 #ifdef CONFIG_ETRAX_SERIAL_PORT3
228 | IO_MASK(R_IRQ_MASK1_RD, ser3_data) | IO_MASK(R_IRQ_MASK1_RD, ser3_ready)
229 #endif
230 ;
231 unsigned long r_alt_ser_baudrate_shadow = 0;
232
233 /* this is the data for the four serial ports in the etrax100 */
234 /*  DMA2(ser2), DMA4(ser3), DMA6(ser0) or DMA8(ser1) */
235 /* R_DMA_CHx_CLR_INTR, R_DMA_CHx_FIRST, R_DMA_CHx_CMD */
236
237 static struct e100_serial rs_table[] = {
238         { .baud        = DEF_BAUD,
239           .ioport        = (unsigned char *)R_SERIAL0_CTRL,
240           .irq         = 1U << 12, /* uses DMA 6 and 7 */
241           .oclrintradr = R_DMA_CH6_CLR_INTR,
242           .ofirstadr   = R_DMA_CH6_FIRST,
243           .ocmdadr     = R_DMA_CH6_CMD,
244           .ostatusadr  = R_DMA_CH6_STATUS,
245           .iclrintradr = R_DMA_CH7_CLR_INTR,
246           .ifirstadr   = R_DMA_CH7_FIRST,
247           .icmdadr     = R_DMA_CH7_CMD,
248           .idescradr   = R_DMA_CH7_DESCR,
249           .flags       = STD_FLAGS,
250           .rx_ctrl     = DEF_RX,
251           .tx_ctrl     = DEF_TX,
252           .iseteop     = 2,
253           .dma_owner   = dma_ser0,
254           .io_if       = if_serial_0,
255 #ifdef CONFIG_ETRAX_SERIAL_PORT0
256           .enabled  = 1,
257 #ifdef CONFIG_ETRAX_SERIAL_PORT0_DMA6_OUT
258           .dma_out_enabled = 1,
259           .dma_out_nbr = SER0_TX_DMA_NBR,
260           .dma_out_irq_nbr = SER0_DMA_TX_IRQ_NBR,
261           .dma_out_irq_flags = 0,
262           .dma_out_irq_description = "serial 0 dma tr",
263 #else
264           .dma_out_enabled = 0,
265           .dma_out_nbr = UINT_MAX,
266           .dma_out_irq_nbr = 0,
267           .dma_out_irq_flags = 0,
268           .dma_out_irq_description = NULL,
269 #endif
270 #ifdef CONFIG_ETRAX_SERIAL_PORT0_DMA7_IN
271           .dma_in_enabled = 1,
272           .dma_in_nbr = SER0_RX_DMA_NBR,
273           .dma_in_irq_nbr = SER0_DMA_RX_IRQ_NBR,
274           .dma_in_irq_flags = 0,
275           .dma_in_irq_description = "serial 0 dma rec",
276 #else
277           .dma_in_enabled = 0,
278           .dma_in_nbr = UINT_MAX,
279           .dma_in_irq_nbr = 0,
280           .dma_in_irq_flags = 0,
281           .dma_in_irq_description = NULL,
282 #endif
283 #else
284           .enabled  = 0,
285           .io_if_description = NULL,
286           .dma_out_enabled = 0,
287           .dma_in_enabled = 0
288 #endif
289
290 },  /* ttyS0 */
291 #ifndef CONFIG_SVINTO_SIM
292         { .baud        = DEF_BAUD,
293           .ioport        = (unsigned char *)R_SERIAL1_CTRL,
294           .irq         = 1U << 16, /* uses DMA 8 and 9 */
295           .oclrintradr = R_DMA_CH8_CLR_INTR,
296           .ofirstadr   = R_DMA_CH8_FIRST,
297           .ocmdadr     = R_DMA_CH8_CMD,
298           .ostatusadr  = R_DMA_CH8_STATUS,
299           .iclrintradr = R_DMA_CH9_CLR_INTR,
300           .ifirstadr   = R_DMA_CH9_FIRST,
301           .icmdadr     = R_DMA_CH9_CMD,
302           .idescradr   = R_DMA_CH9_DESCR,
303           .flags       = STD_FLAGS,
304           .rx_ctrl     = DEF_RX,
305           .tx_ctrl     = DEF_TX,
306           .iseteop     = 3,
307           .dma_owner   = dma_ser1,
308           .io_if       = if_serial_1,
309 #ifdef CONFIG_ETRAX_SERIAL_PORT1
310           .enabled  = 1,
311           .io_if_description = "ser1",
312 #ifdef CONFIG_ETRAX_SERIAL_PORT1_DMA8_OUT
313           .dma_out_enabled = 1,
314           .dma_out_nbr = SER1_TX_DMA_NBR,
315           .dma_out_irq_nbr = SER1_DMA_TX_IRQ_NBR,
316           .dma_out_irq_flags = 0,
317           .dma_out_irq_description = "serial 1 dma tr",
318 #else
319           .dma_out_enabled = 0,
320           .dma_out_nbr = UINT_MAX,
321           .dma_out_irq_nbr = 0,
322           .dma_out_irq_flags = 0,
323           .dma_out_irq_description = NULL,
324 #endif
325 #ifdef CONFIG_ETRAX_SERIAL_PORT1_DMA9_IN
326           .dma_in_enabled = 1,
327           .dma_in_nbr = SER1_RX_DMA_NBR,
328           .dma_in_irq_nbr = SER1_DMA_RX_IRQ_NBR,
329           .dma_in_irq_flags = 0,
330           .dma_in_irq_description = "serial 1 dma rec",
331 #else
332           .dma_in_enabled = 0,
333           .dma_in_enabled = 0,
334           .dma_in_nbr = UINT_MAX,
335           .dma_in_irq_nbr = 0,
336           .dma_in_irq_flags = 0,
337           .dma_in_irq_description = NULL,
338 #endif
339 #else
340           .enabled  = 0,
341           .io_if_description = NULL,
342           .dma_in_irq_nbr = 0,
343           .dma_out_enabled = 0,
344           .dma_in_enabled = 0
345 #endif
346 },  /* ttyS1 */
347
348         { .baud        = DEF_BAUD,
349           .ioport        = (unsigned char *)R_SERIAL2_CTRL,
350           .irq         = 1U << 4,  /* uses DMA 2 and 3 */
351           .oclrintradr = R_DMA_CH2_CLR_INTR,
352           .ofirstadr   = R_DMA_CH2_FIRST,
353           .ocmdadr     = R_DMA_CH2_CMD,
354           .ostatusadr  = R_DMA_CH2_STATUS,
355           .iclrintradr = R_DMA_CH3_CLR_INTR,
356           .ifirstadr   = R_DMA_CH3_FIRST,
357           .icmdadr     = R_DMA_CH3_CMD,
358           .idescradr   = R_DMA_CH3_DESCR,
359           .flags       = STD_FLAGS,
360           .rx_ctrl     = DEF_RX,
361           .tx_ctrl     = DEF_TX,
362           .iseteop     = 0,
363           .dma_owner   = dma_ser2,
364           .io_if       = if_serial_2,
365 #ifdef CONFIG_ETRAX_SERIAL_PORT2
366           .enabled  = 1,
367           .io_if_description = "ser2",
368 #ifdef CONFIG_ETRAX_SERIAL_PORT2_DMA2_OUT
369           .dma_out_enabled = 1,
370           .dma_out_nbr = SER2_TX_DMA_NBR,
371           .dma_out_irq_nbr = SER2_DMA_TX_IRQ_NBR,
372           .dma_out_irq_flags = 0,
373           .dma_out_irq_description = "serial 2 dma tr",
374 #else
375           .dma_out_enabled = 0,
376           .dma_out_nbr = UINT_MAX,
377           .dma_out_irq_nbr = 0,
378           .dma_out_irq_flags = 0,
379           .dma_out_irq_description = NULL,
380 #endif
381 #ifdef CONFIG_ETRAX_SERIAL_PORT2_DMA3_IN
382           .dma_in_enabled = 1,
383           .dma_in_nbr = SER2_RX_DMA_NBR,
384           .dma_in_irq_nbr = SER2_DMA_RX_IRQ_NBR,
385           .dma_in_irq_flags = 0,
386           .dma_in_irq_description = "serial 2 dma rec",
387 #else
388           .dma_in_enabled = 0,
389           .dma_in_nbr = UINT_MAX,
390           .dma_in_irq_nbr = 0,
391           .dma_in_irq_flags = 0,
392           .dma_in_irq_description = NULL,
393 #endif
394 #else
395           .enabled  = 0,
396           .io_if_description = NULL,
397           .dma_out_enabled = 0,
398           .dma_in_enabled = 0
399 #endif
400  },  /* ttyS2 */
401
402         { .baud        = DEF_BAUD,
403           .ioport        = (unsigned char *)R_SERIAL3_CTRL,
404           .irq         = 1U << 8,  /* uses DMA 4 and 5 */
405           .oclrintradr = R_DMA_CH4_CLR_INTR,
406           .ofirstadr   = R_DMA_CH4_FIRST,
407           .ocmdadr     = R_DMA_CH4_CMD,
408           .ostatusadr  = R_DMA_CH4_STATUS,
409           .iclrintradr = R_DMA_CH5_CLR_INTR,
410           .ifirstadr   = R_DMA_CH5_FIRST,
411           .icmdadr     = R_DMA_CH5_CMD,
412           .idescradr   = R_DMA_CH5_DESCR,
413           .flags       = STD_FLAGS,
414           .rx_ctrl     = DEF_RX,
415           .tx_ctrl     = DEF_TX,
416           .iseteop     = 1,
417           .dma_owner   = dma_ser3,
418           .io_if       = if_serial_3,
419 #ifdef CONFIG_ETRAX_SERIAL_PORT3
420           .enabled  = 1,
421           .io_if_description = "ser3",
422 #ifdef CONFIG_ETRAX_SERIAL_PORT3_DMA4_OUT
423           .dma_out_enabled = 1,
424           .dma_out_nbr = SER3_TX_DMA_NBR,
425           .dma_out_irq_nbr = SER3_DMA_TX_IRQ_NBR,
426           .dma_out_irq_flags = 0,
427           .dma_out_irq_description = "serial 3 dma tr",
428 #else
429           .dma_out_enabled = 0,
430           .dma_out_nbr = UINT_MAX,
431           .dma_out_irq_nbr = 0,
432           .dma_out_irq_flags = 0,
433           .dma_out_irq_description = NULL,
434 #endif
435 #ifdef CONFIG_ETRAX_SERIAL_PORT3_DMA5_IN
436           .dma_in_enabled = 1,
437           .dma_in_nbr = SER3_RX_DMA_NBR,
438           .dma_in_irq_nbr = SER3_DMA_RX_IRQ_NBR,
439           .dma_in_irq_flags = 0,
440           .dma_in_irq_description = "serial 3 dma rec",
441 #else
442           .dma_in_enabled = 0,
443           .dma_in_nbr = UINT_MAX,
444           .dma_in_irq_nbr = 0,
445           .dma_in_irq_flags = 0,
446           .dma_in_irq_description = NULL
447 #endif
448 #else
449           .enabled  = 0,
450           .io_if_description = NULL,
451           .dma_out_enabled = 0,
452           .dma_in_enabled = 0
453 #endif
454  }   /* ttyS3 */
455 #endif
456 };
457
458
459 #define NR_PORTS (sizeof(rs_table)/sizeof(struct e100_serial))
460
461 #ifdef CONFIG_ETRAX_SERIAL_FAST_TIMER
462 static struct fast_timer fast_timers[NR_PORTS];
463 #endif
464
465 #ifdef CONFIG_ETRAX_SERIAL_PROC_ENTRY
466 #define PROCSTAT(x) x
467 struct ser_statistics_type {
468         int overrun_cnt;
469         int early_errors_cnt;
470         int ser_ints_ok_cnt;
471         int errors_cnt;
472         unsigned long int processing_flip;
473         unsigned long processing_flip_still_room;
474         unsigned long int timeout_flush_cnt;
475         int rx_dma_ints;
476         int tx_dma_ints;
477         int rx_tot;
478         int tx_tot;
479 };
480
481 static struct ser_statistics_type ser_stat[NR_PORTS];
482
483 #else
484
485 #define PROCSTAT(x)
486
487 #endif /* CONFIG_ETRAX_SERIAL_PROC_ENTRY */
488
489 /* RS-485 */
490 #if defined(CONFIG_ETRAX_RS485)
491 #ifdef CONFIG_ETRAX_FAST_TIMER
492 static struct fast_timer fast_timers_rs485[NR_PORTS];
493 #endif
494 #if defined(CONFIG_ETRAX_RS485_ON_PA)
495 static int rs485_pa_bit = CONFIG_ETRAX_RS485_ON_PA_BIT;
496 #endif
497 #if defined(CONFIG_ETRAX_RS485_ON_PORT_G)
498 static int rs485_port_g_bit = CONFIG_ETRAX_RS485_ON_PORT_G_BIT;
499 #endif
500 #endif
501
502 /* Info and macros needed for each ports extra control/status signals. */
503 #define E100_STRUCT_PORT(line, pinname) \
504  ((CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT >= 0)? \
505                 (R_PORT_PA_DATA): ( \
506  (CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT >= 0)? \
507                 (R_PORT_PB_DATA):&dummy_ser[line]))
508
509 #define E100_STRUCT_SHADOW(line, pinname) \
510  ((CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT >= 0)? \
511                 (&port_pa_data_shadow): ( \
512  (CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT >= 0)? \
513                 (&port_pb_data_shadow):&dummy_ser[line]))
514 #define E100_STRUCT_MASK(line, pinname) \
515  ((CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT >= 0)? \
516                 (1<<CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT): ( \
517  (CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT >= 0)? \
518                 (1<<CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT):DUMMY_##pinname##_MASK))
519
520 #define DUMMY_DTR_MASK 1
521 #define DUMMY_RI_MASK  2
522 #define DUMMY_DSR_MASK 4
523 #define DUMMY_CD_MASK  8
524 static unsigned char dummy_ser[NR_PORTS] = {0xFF, 0xFF, 0xFF,0xFF};
525
526 /* If not all status pins are used or disabled, use mixed mode */
527 #ifdef CONFIG_ETRAX_SERIAL_PORT0
528
529 #define SER0_PA_BITSUM (CONFIG_ETRAX_SER0_DTR_ON_PA_BIT+CONFIG_ETRAX_SER0_RI_ON_PA_BIT+CONFIG_ETRAX_SER0_DSR_ON_PA_BIT+CONFIG_ETRAX_SER0_CD_ON_PA_BIT)
530
531 #if SER0_PA_BITSUM != -4
532 #  if CONFIG_ETRAX_SER0_DTR_ON_PA_BIT == -1
533 #    ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
534 #      define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
535 #    endif
536 #   endif
537 # if CONFIG_ETRAX_SER0_RI_ON_PA_BIT == -1
538 #   ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
539 #     define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
540 #   endif
541 #  endif
542 #  if CONFIG_ETRAX_SER0_DSR_ON_PA_BIT == -1
543 #    ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
544 #      define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
545 #    endif
546 #  endif
547 #  if CONFIG_ETRAX_SER0_CD_ON_PA_BIT == -1
548 #    ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
549 #      define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
550 #    endif
551 #  endif
552 #endif
553
554 #define SER0_PB_BITSUM (CONFIG_ETRAX_SER0_DTR_ON_PB_BIT+CONFIG_ETRAX_SER0_RI_ON_PB_BIT+CONFIG_ETRAX_SER0_DSR_ON_PB_BIT+CONFIG_ETRAX_SER0_CD_ON_PB_BIT)
555
556 #if SER0_PB_BITSUM != -4
557 #  if CONFIG_ETRAX_SER0_DTR_ON_PB_BIT == -1
558 #    ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
559 #      define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
560 #    endif
561 #   endif
562 # if CONFIG_ETRAX_SER0_RI_ON_PB_BIT == -1
563 #   ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
564 #     define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
565 #   endif
566 #  endif
567 #  if CONFIG_ETRAX_SER0_DSR_ON_PB_BIT == -1
568 #    ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
569 #      define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
570 #    endif
571 #  endif
572 #  if CONFIG_ETRAX_SER0_CD_ON_PB_BIT == -1
573 #    ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
574 #      define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
575 #    endif
576 #  endif
577 #endif
578
579 #endif /* PORT0 */
580
581
582 #ifdef CONFIG_ETRAX_SERIAL_PORT1
583
584 #define SER1_PA_BITSUM (CONFIG_ETRAX_SER1_DTR_ON_PA_BIT+CONFIG_ETRAX_SER1_RI_ON_PA_BIT+CONFIG_ETRAX_SER1_DSR_ON_PA_BIT+CONFIG_ETRAX_SER1_CD_ON_PA_BIT)
585
586 #if SER1_PA_BITSUM != -4
587 #  if CONFIG_ETRAX_SER1_DTR_ON_PA_BIT == -1
588 #    ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
589 #      define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
590 #    endif
591 #   endif
592 # if CONFIG_ETRAX_SER1_RI_ON_PA_BIT == -1
593 #   ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
594 #     define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
595 #   endif
596 #  endif
597 #  if CONFIG_ETRAX_SER1_DSR_ON_PA_BIT == -1
598 #    ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
599 #      define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
600 #    endif
601 #  endif
602 #  if CONFIG_ETRAX_SER1_CD_ON_PA_BIT == -1
603 #    ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
604 #      define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
605 #    endif
606 #  endif
607 #endif
608
609 #define SER1_PB_BITSUM (CONFIG_ETRAX_SER1_DTR_ON_PB_BIT+CONFIG_ETRAX_SER1_RI_ON_PB_BIT+CONFIG_ETRAX_SER1_DSR_ON_PB_BIT+CONFIG_ETRAX_SER1_CD_ON_PB_BIT)
610
611 #if SER1_PB_BITSUM != -4
612 #  if CONFIG_ETRAX_SER1_DTR_ON_PB_BIT == -1
613 #    ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
614 #      define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
615 #    endif
616 #   endif
617 # if CONFIG_ETRAX_SER1_RI_ON_PB_BIT == -1
618 #   ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
619 #     define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
620 #   endif
621 #  endif
622 #  if CONFIG_ETRAX_SER1_DSR_ON_PB_BIT == -1
623 #    ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
624 #      define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
625 #    endif
626 #  endif
627 #  if CONFIG_ETRAX_SER1_CD_ON_PB_BIT == -1
628 #    ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
629 #      define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
630 #    endif
631 #  endif
632 #endif
633
634 #endif /* PORT1 */
635
636 #ifdef CONFIG_ETRAX_SERIAL_PORT2
637
638 #define SER2_PA_BITSUM (CONFIG_ETRAX_SER2_DTR_ON_PA_BIT+CONFIG_ETRAX_SER2_RI_ON_PA_BIT+CONFIG_ETRAX_SER2_DSR_ON_PA_BIT+CONFIG_ETRAX_SER2_CD_ON_PA_BIT)
639
640 #if SER2_PA_BITSUM != -4
641 #  if CONFIG_ETRAX_SER2_DTR_ON_PA_BIT == -1
642 #    ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
643 #      define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
644 #    endif
645 #   endif
646 # if CONFIG_ETRAX_SER2_RI_ON_PA_BIT == -1
647 #   ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
648 #     define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
649 #   endif
650 #  endif
651 #  if CONFIG_ETRAX_SER2_DSR_ON_PA_BIT == -1
652 #    ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
653 #      define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
654 #    endif
655 #  endif
656 #  if CONFIG_ETRAX_SER2_CD_ON_PA_BIT == -1
657 #    ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
658 #      define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
659 #    endif
660 #  endif
661 #endif
662
663 #define SER2_PB_BITSUM (CONFIG_ETRAX_SER2_DTR_ON_PB_BIT+CONFIG_ETRAX_SER2_RI_ON_PB_BIT+CONFIG_ETRAX_SER2_DSR_ON_PB_BIT+CONFIG_ETRAX_SER2_CD_ON_PB_BIT)
664
665 #if SER2_PB_BITSUM != -4
666 #  if CONFIG_ETRAX_SER2_DTR_ON_PB_BIT == -1
667 #    ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
668 #      define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
669 #    endif
670 #   endif
671 # if CONFIG_ETRAX_SER2_RI_ON_PB_BIT == -1
672 #   ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
673 #     define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
674 #   endif
675 #  endif
676 #  if CONFIG_ETRAX_SER2_DSR_ON_PB_BIT == -1
677 #    ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
678 #      define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
679 #    endif
680 #  endif
681 #  if CONFIG_ETRAX_SER2_CD_ON_PB_BIT == -1
682 #    ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
683 #      define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
684 #    endif
685 #  endif
686 #endif
687
688 #endif /* PORT2 */
689
690 #ifdef CONFIG_ETRAX_SERIAL_PORT3
691
692 #define SER3_PA_BITSUM (CONFIG_ETRAX_SER3_DTR_ON_PA_BIT+CONFIG_ETRAX_SER3_RI_ON_PA_BIT+CONFIG_ETRAX_SER3_DSR_ON_PA_BIT+CONFIG_ETRAX_SER3_CD_ON_PA_BIT)
693
694 #if SER3_PA_BITSUM != -4
695 #  if CONFIG_ETRAX_SER3_DTR_ON_PA_BIT == -1
696 #    ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
697 #      define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
698 #    endif
699 #   endif
700 # if CONFIG_ETRAX_SER3_RI_ON_PA_BIT == -1
701 #   ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
702 #     define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
703 #   endif
704 #  endif
705 #  if CONFIG_ETRAX_SER3_DSR_ON_PA_BIT == -1
706 #    ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
707 #      define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
708 #    endif
709 #  endif
710 #  if CONFIG_ETRAX_SER3_CD_ON_PA_BIT == -1
711 #    ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
712 #      define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
713 #    endif
714 #  endif
715 #endif
716
717 #define SER3_PB_BITSUM (CONFIG_ETRAX_SER3_DTR_ON_PB_BIT+CONFIG_ETRAX_SER3_RI_ON_PB_BIT+CONFIG_ETRAX_SER3_DSR_ON_PB_BIT+CONFIG_ETRAX_SER3_CD_ON_PB_BIT)
718
719 #if SER3_PB_BITSUM != -4
720 #  if CONFIG_ETRAX_SER3_DTR_ON_PB_BIT == -1
721 #    ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
722 #      define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
723 #    endif
724 #   endif
725 # if CONFIG_ETRAX_SER3_RI_ON_PB_BIT == -1
726 #   ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
727 #     define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
728 #   endif
729 #  endif
730 #  if CONFIG_ETRAX_SER3_DSR_ON_PB_BIT == -1
731 #    ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
732 #      define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
733 #    endif
734 #  endif
735 #  if CONFIG_ETRAX_SER3_CD_ON_PB_BIT == -1
736 #    ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
737 #      define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
738 #    endif
739 #  endif
740 #endif
741
742 #endif /* PORT3 */
743
744
745 #if defined(CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED) || \
746     defined(CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED) || \
747     defined(CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED) || \
748     defined(CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED)
749 #define CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED
750 #endif
751
752 #ifdef CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED
753 /* The pins can be mixed on PA and PB */
754 #define CONTROL_PINS_PORT_NOT_USED(line) \
755   &dummy_ser[line], &dummy_ser[line], \
756   &dummy_ser[line], &dummy_ser[line], \
757   &dummy_ser[line], &dummy_ser[line], \
758   &dummy_ser[line], &dummy_ser[line], \
759   DUMMY_DTR_MASK, DUMMY_RI_MASK, DUMMY_DSR_MASK, DUMMY_CD_MASK
760
761
762 struct control_pins
763 {
764         volatile unsigned char *dtr_port;
765         unsigned char          *dtr_shadow;
766         volatile unsigned char *ri_port;
767         unsigned char          *ri_shadow;
768         volatile unsigned char *dsr_port;
769         unsigned char          *dsr_shadow;
770         volatile unsigned char *cd_port;
771         unsigned char          *cd_shadow;
772
773         unsigned char dtr_mask;
774         unsigned char ri_mask;
775         unsigned char dsr_mask;
776         unsigned char cd_mask;
777 };
778
779 static const struct control_pins e100_modem_pins[NR_PORTS] =
780 {
781         /* Ser 0 */
782         {
783 #ifdef CONFIG_ETRAX_SERIAL_PORT0
784         E100_STRUCT_PORT(0,DTR), E100_STRUCT_SHADOW(0,DTR),
785         E100_STRUCT_PORT(0,RI),  E100_STRUCT_SHADOW(0,RI),
786         E100_STRUCT_PORT(0,DSR), E100_STRUCT_SHADOW(0,DSR),
787         E100_STRUCT_PORT(0,CD),  E100_STRUCT_SHADOW(0,CD),
788         E100_STRUCT_MASK(0,DTR),
789         E100_STRUCT_MASK(0,RI),
790         E100_STRUCT_MASK(0,DSR),
791         E100_STRUCT_MASK(0,CD)
792 #else
793         CONTROL_PINS_PORT_NOT_USED(0)
794 #endif
795         },
796
797         /* Ser 1 */
798         {
799 #ifdef CONFIG_ETRAX_SERIAL_PORT1
800         E100_STRUCT_PORT(1,DTR), E100_STRUCT_SHADOW(1,DTR),
801         E100_STRUCT_PORT(1,RI),  E100_STRUCT_SHADOW(1,RI),
802         E100_STRUCT_PORT(1,DSR), E100_STRUCT_SHADOW(1,DSR),
803         E100_STRUCT_PORT(1,CD),  E100_STRUCT_SHADOW(1,CD),
804         E100_STRUCT_MASK(1,DTR),
805         E100_STRUCT_MASK(1,RI),
806         E100_STRUCT_MASK(1,DSR),
807         E100_STRUCT_MASK(1,CD)
808 #else
809         CONTROL_PINS_PORT_NOT_USED(1)
810 #endif
811         },
812
813         /* Ser 2 */
814         {
815 #ifdef CONFIG_ETRAX_SERIAL_PORT2
816         E100_STRUCT_PORT(2,DTR), E100_STRUCT_SHADOW(2,DTR),
817         E100_STRUCT_PORT(2,RI),  E100_STRUCT_SHADOW(2,RI),
818         E100_STRUCT_PORT(2,DSR), E100_STRUCT_SHADOW(2,DSR),
819         E100_STRUCT_PORT(2,CD),  E100_STRUCT_SHADOW(2,CD),
820         E100_STRUCT_MASK(2,DTR),
821         E100_STRUCT_MASK(2,RI),
822         E100_STRUCT_MASK(2,DSR),
823         E100_STRUCT_MASK(2,CD)
824 #else
825         CONTROL_PINS_PORT_NOT_USED(2)
826 #endif
827         },
828
829         /* Ser 3 */
830         {
831 #ifdef CONFIG_ETRAX_SERIAL_PORT3
832         E100_STRUCT_PORT(3,DTR), E100_STRUCT_SHADOW(3,DTR),
833         E100_STRUCT_PORT(3,RI),  E100_STRUCT_SHADOW(3,RI),
834         E100_STRUCT_PORT(3,DSR), E100_STRUCT_SHADOW(3,DSR),
835         E100_STRUCT_PORT(3,CD),  E100_STRUCT_SHADOW(3,CD),
836         E100_STRUCT_MASK(3,DTR),
837         E100_STRUCT_MASK(3,RI),
838         E100_STRUCT_MASK(3,DSR),
839         E100_STRUCT_MASK(3,CD)
840 #else
841         CONTROL_PINS_PORT_NOT_USED(3)
842 #endif
843         }
844 };
845 #else  /* CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED */
846
847 /* All pins are on either PA or PB for each serial port */
848 #define CONTROL_PINS_PORT_NOT_USED(line) \
849   &dummy_ser[line], &dummy_ser[line], \
850   DUMMY_DTR_MASK, DUMMY_RI_MASK, DUMMY_DSR_MASK, DUMMY_CD_MASK
851
852
853 struct control_pins
854 {
855         volatile unsigned char *port;
856         unsigned char          *shadow;
857
858         unsigned char dtr_mask;
859         unsigned char ri_mask;
860         unsigned char dsr_mask;
861         unsigned char cd_mask;
862 };
863
864 #define dtr_port port
865 #define dtr_shadow shadow
866 #define ri_port port
867 #define ri_shadow shadow
868 #define dsr_port port
869 #define dsr_shadow shadow
870 #define cd_port port
871 #define cd_shadow shadow
872
873 static const struct control_pins e100_modem_pins[NR_PORTS] =
874 {
875         /* Ser 0 */
876         {
877 #ifdef CONFIG_ETRAX_SERIAL_PORT0
878         E100_STRUCT_PORT(0,DTR), E100_STRUCT_SHADOW(0,DTR),
879         E100_STRUCT_MASK(0,DTR),
880         E100_STRUCT_MASK(0,RI),
881         E100_STRUCT_MASK(0,DSR),
882         E100_STRUCT_MASK(0,CD)
883 #else
884         CONTROL_PINS_PORT_NOT_USED(0)
885 #endif
886         },
887
888         /* Ser 1 */
889         {
890 #ifdef CONFIG_ETRAX_SERIAL_PORT1
891         E100_STRUCT_PORT(1,DTR), E100_STRUCT_SHADOW(1,DTR),
892         E100_STRUCT_MASK(1,DTR),
893         E100_STRUCT_MASK(1,RI),
894         E100_STRUCT_MASK(1,DSR),
895         E100_STRUCT_MASK(1,CD)
896 #else
897         CONTROL_PINS_PORT_NOT_USED(1)
898 #endif
899         },
900
901         /* Ser 2 */
902         {
903 #ifdef CONFIG_ETRAX_SERIAL_PORT2
904         E100_STRUCT_PORT(2,DTR), E100_STRUCT_SHADOW(2,DTR),
905         E100_STRUCT_MASK(2,DTR),
906         E100_STRUCT_MASK(2,RI),
907         E100_STRUCT_MASK(2,DSR),
908         E100_STRUCT_MASK(2,CD)
909 #else
910         CONTROL_PINS_PORT_NOT_USED(2)
911 #endif
912         },
913
914         /* Ser 3 */
915         {
916 #ifdef CONFIG_ETRAX_SERIAL_PORT3
917         E100_STRUCT_PORT(3,DTR), E100_STRUCT_SHADOW(3,DTR),
918         E100_STRUCT_MASK(3,DTR),
919         E100_STRUCT_MASK(3,RI),
920         E100_STRUCT_MASK(3,DSR),
921         E100_STRUCT_MASK(3,CD)
922 #else
923         CONTROL_PINS_PORT_NOT_USED(3)
924 #endif
925         }
926 };
927 #endif /* !CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED */
928
929 #define E100_RTS_MASK 0x20
930 #define E100_CTS_MASK 0x40
931
932 /* All serial port signals are active low:
933  * active   = 0 -> 3.3V to RS-232 driver -> -12V on RS-232 level
934  * inactive = 1 -> 0V   to RS-232 driver -> +12V on RS-232 level
935  *
936  * These macros returns the pin value: 0=0V, >=1 = 3.3V on ETRAX chip
937  */
938
939 /* Output */
940 #define E100_RTS_GET(info) ((info)->rx_ctrl & E100_RTS_MASK)
941 /* Input */
942 #define E100_CTS_GET(info) ((info)->ioport[REG_STATUS] & E100_CTS_MASK)
943
944 /* These are typically PA or PB and 0 means 0V, 1 means 3.3V */
945 /* Is an output */
946 #define E100_DTR_GET(info) ((*e100_modem_pins[(info)->line].dtr_shadow) & e100_modem_pins[(info)->line].dtr_mask)
947
948 /* Normally inputs */
949 #define E100_RI_GET(info) ((*e100_modem_pins[(info)->line].ri_port) & e100_modem_pins[(info)->line].ri_mask)
950 #define E100_CD_GET(info) ((*e100_modem_pins[(info)->line].cd_port) & e100_modem_pins[(info)->line].cd_mask)
951
952 /* Input */
953 #define E100_DSR_GET(info) ((*e100_modem_pins[(info)->line].dsr_port) & e100_modem_pins[(info)->line].dsr_mask)
954
955 /* Calculate the chartime depending on baudrate, numbor of bits etc. */
956 static void update_char_time(struct e100_serial * info)
957 {
958         tcflag_t cflags = info->port.tty->termios->c_cflag;
959         int bits;
960
961         /* calc. number of bits / data byte */
962         /* databits + startbit and 1 stopbit */
963         if ((cflags & CSIZE) == CS7)
964                 bits = 9;
965         else
966                 bits = 10;
967
968         if (cflags & CSTOPB)     /* 2 stopbits ? */
969                 bits++;
970
971         if (cflags & PARENB)     /* parity bit ? */
972                 bits++;
973
974         /* calc timeout */
975         info->char_time_usec = ((bits * 1000000) / info->baud) + 1;
976         info->flush_time_usec = 4*info->char_time_usec;
977         if (info->flush_time_usec < MIN_FLUSH_TIME_USEC)
978                 info->flush_time_usec = MIN_FLUSH_TIME_USEC;
979
980 }
981
982 /*
983  * This function maps from the Bxxxx defines in asm/termbits.h into real
984  * baud rates.
985  */
986
987 static int
988 cflag_to_baud(unsigned int cflag)
989 {
990         static int baud_table[] = {
991                 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400,
992                 4800, 9600, 19200, 38400 };
993
994         static int ext_baud_table[] = {
995                 0, 57600, 115200, 230400, 460800, 921600, 1843200, 6250000,
996                 0, 0, 0, 0, 0, 0, 0, 0 };
997
998         if (cflag & CBAUDEX)
999                 return ext_baud_table[(cflag & CBAUD) & ~CBAUDEX];
1000         else
1001                 return baud_table[cflag & CBAUD];
1002 }
1003
1004 /* and this maps to an etrax100 hardware baud constant */
1005
1006 static unsigned char
1007 cflag_to_etrax_baud(unsigned int cflag)
1008 {
1009         char retval;
1010
1011         static char baud_table[] = {
1012                 -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, -1, 3, 4, 5, 6, 7 };
1013
1014         static char ext_baud_table[] = {
1015                 -1, 8, 9, 10, 11, 12, 13, 14, -1, -1, -1, -1, -1, -1, -1, -1 };
1016
1017         if (cflag & CBAUDEX)
1018                 retval = ext_baud_table[(cflag & CBAUD) & ~CBAUDEX];
1019         else
1020                 retval = baud_table[cflag & CBAUD];
1021
1022         if (retval < 0) {
1023                 printk(KERN_WARNING "serdriver tried setting invalid baud rate, flags %x.\n", cflag);
1024                 retval = 5; /* choose default 9600 instead */
1025         }
1026
1027         return retval | (retval << 4); /* choose same for both TX and RX */
1028 }
1029
1030
1031 /* Various static support functions */
1032
1033 /* Functions to set or clear DTR/RTS on the requested line */
1034 /* It is complicated by the fact that RTS is a serial port register, while
1035  * DTR might not be implemented in the HW at all, and if it is, it can be on
1036  * any general port.
1037  */
1038
1039
1040 static inline void
1041 e100_dtr(struct e100_serial *info, int set)
1042 {
1043 #ifndef CONFIG_SVINTO_SIM
1044         unsigned char mask = e100_modem_pins[info->line].dtr_mask;
1045
1046 #ifdef SERIAL_DEBUG_IO
1047         printk("ser%i dtr %i mask: 0x%02X\n", info->line, set, mask);
1048         printk("ser%i shadow before 0x%02X get: %i\n",
1049                info->line, *e100_modem_pins[info->line].dtr_shadow,
1050                E100_DTR_GET(info));
1051 #endif
1052         /* DTR is active low */
1053         {
1054                 unsigned long flags;
1055
1056                 local_irq_save(flags);
1057                 *e100_modem_pins[info->line].dtr_shadow &= ~mask;
1058                 *e100_modem_pins[info->line].dtr_shadow |= (set ? 0 : mask);
1059                 *e100_modem_pins[info->line].dtr_port = *e100_modem_pins[info->line].dtr_shadow;
1060                 local_irq_restore(flags);
1061         }
1062
1063 #ifdef SERIAL_DEBUG_IO
1064         printk("ser%i shadow after 0x%02X get: %i\n",
1065                info->line, *e100_modem_pins[info->line].dtr_shadow,
1066                E100_DTR_GET(info));
1067 #endif
1068 #endif
1069 }
1070
1071 /* set = 0 means 3.3V on the pin, bitvalue: 0=active, 1=inactive
1072  *                                          0=0V    , 1=3.3V
1073  */
1074 static inline void
1075 e100_rts(struct e100_serial *info, int set)
1076 {
1077 #ifndef CONFIG_SVINTO_SIM
1078         unsigned long flags;
1079         local_irq_save(flags);
1080         info->rx_ctrl &= ~E100_RTS_MASK;
1081         info->rx_ctrl |= (set ? 0 : E100_RTS_MASK);  /* RTS is active low */
1082         info->ioport[REG_REC_CTRL] = info->rx_ctrl;
1083         local_irq_restore(flags);
1084 #ifdef SERIAL_DEBUG_IO
1085         printk("ser%i rts %i\n", info->line, set);
1086 #endif
1087 #endif
1088 }
1089
1090
1091 /* If this behaves as a modem, RI and CD is an output */
1092 static inline void
1093 e100_ri_out(struct e100_serial *info, int set)
1094 {
1095 #ifndef CONFIG_SVINTO_SIM
1096         /* RI is active low */
1097         {
1098                 unsigned char mask = e100_modem_pins[info->line].ri_mask;
1099                 unsigned long flags;
1100
1101                 local_irq_save(flags);
1102                 *e100_modem_pins[info->line].ri_shadow &= ~mask;
1103                 *e100_modem_pins[info->line].ri_shadow |= (set ? 0 : mask);
1104                 *e100_modem_pins[info->line].ri_port = *e100_modem_pins[info->line].ri_shadow;
1105                 local_irq_restore(flags);
1106         }
1107 #endif
1108 }
1109 static inline void
1110 e100_cd_out(struct e100_serial *info, int set)
1111 {
1112 #ifndef CONFIG_SVINTO_SIM
1113         /* CD is active low */
1114         {
1115                 unsigned char mask = e100_modem_pins[info->line].cd_mask;
1116                 unsigned long flags;
1117
1118                 local_irq_save(flags);
1119                 *e100_modem_pins[info->line].cd_shadow &= ~mask;
1120                 *e100_modem_pins[info->line].cd_shadow |= (set ? 0 : mask);
1121                 *e100_modem_pins[info->line].cd_port = *e100_modem_pins[info->line].cd_shadow;
1122                 local_irq_restore(flags);
1123         }
1124 #endif
1125 }
1126
1127 static inline void
1128 e100_disable_rx(struct e100_serial *info)
1129 {
1130 #ifndef CONFIG_SVINTO_SIM
1131         /* disable the receiver */
1132         info->ioport[REG_REC_CTRL] =
1133                 (info->rx_ctrl &= ~IO_MASK(R_SERIAL0_REC_CTRL, rec_enable));
1134 #endif
1135 }
1136
1137 static inline void
1138 e100_enable_rx(struct e100_serial *info)
1139 {
1140 #ifndef CONFIG_SVINTO_SIM
1141         /* enable the receiver */
1142         info->ioport[REG_REC_CTRL] =
1143                 (info->rx_ctrl |= IO_MASK(R_SERIAL0_REC_CTRL, rec_enable));
1144 #endif
1145 }
1146
1147 /* the rx DMA uses both the dma_descr and the dma_eop interrupts */
1148
1149 static inline void
1150 e100_disable_rxdma_irq(struct e100_serial *info)
1151 {
1152 #ifdef SERIAL_DEBUG_INTR
1153         printk("rxdma_irq(%d): 0\n",info->line);
1154 #endif
1155         DINTR1(DEBUG_LOG(info->line,"IRQ disable_rxdma_irq %i\n", info->line));
1156         *R_IRQ_MASK2_CLR = (info->irq << 2) | (info->irq << 3);
1157 }
1158
1159 static inline void
1160 e100_enable_rxdma_irq(struct e100_serial *info)
1161 {
1162 #ifdef SERIAL_DEBUG_INTR
1163         printk("rxdma_irq(%d): 1\n",info->line);
1164 #endif
1165         DINTR1(DEBUG_LOG(info->line,"IRQ enable_rxdma_irq %i\n", info->line));
1166         *R_IRQ_MASK2_SET = (info->irq << 2) | (info->irq << 3);
1167 }
1168
1169 /* the tx DMA uses only dma_descr interrupt */
1170
1171 static void e100_disable_txdma_irq(struct e100_serial *info)
1172 {
1173 #ifdef SERIAL_DEBUG_INTR
1174         printk("txdma_irq(%d): 0\n",info->line);
1175 #endif
1176         DINTR1(DEBUG_LOG(info->line,"IRQ disable_txdma_irq %i\n", info->line));
1177         *R_IRQ_MASK2_CLR = info->irq;
1178 }
1179
1180 static void e100_enable_txdma_irq(struct e100_serial *info)
1181 {
1182 #ifdef SERIAL_DEBUG_INTR
1183         printk("txdma_irq(%d): 1\n",info->line);
1184 #endif
1185         DINTR1(DEBUG_LOG(info->line,"IRQ enable_txdma_irq %i\n", info->line));
1186         *R_IRQ_MASK2_SET = info->irq;
1187 }
1188
1189 static void e100_disable_txdma_channel(struct e100_serial *info)
1190 {
1191         unsigned long flags;
1192
1193         /* Disable output DMA channel for the serial port in question
1194          * ( set to something other than serialX)
1195          */
1196         local_irq_save(flags);
1197         DFLOW(DEBUG_LOG(info->line, "disable_txdma_channel %i\n", info->line));
1198         if (info->line == 0) {
1199                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma6)) ==
1200                     IO_STATE(R_GEN_CONFIG, dma6, serial0)) {
1201                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma6);
1202                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma6, unused);
1203                 }
1204         } else if (info->line == 1) {
1205                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma8)) ==
1206                     IO_STATE(R_GEN_CONFIG, dma8, serial1)) {
1207                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma8);
1208                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma8, usb);
1209                 }
1210         } else if (info->line == 2) {
1211                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma2)) ==
1212                     IO_STATE(R_GEN_CONFIG, dma2, serial2)) {
1213                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma2);
1214                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma2, par0);
1215                 }
1216         } else if (info->line == 3) {
1217                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma4)) ==
1218                     IO_STATE(R_GEN_CONFIG, dma4, serial3)) {
1219                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma4);
1220                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma4, par1);
1221                 }
1222         }
1223         *R_GEN_CONFIG = genconfig_shadow;
1224         local_irq_restore(flags);
1225 }
1226
1227
1228 static void e100_enable_txdma_channel(struct e100_serial *info)
1229 {
1230         unsigned long flags;
1231
1232         local_irq_save(flags);
1233         DFLOW(DEBUG_LOG(info->line, "enable_txdma_channel %i\n", info->line));
1234         /* Enable output DMA channel for the serial port in question */
1235         if (info->line == 0) {
1236                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma6);
1237                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma6, serial0);
1238         } else if (info->line == 1) {
1239                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma8);
1240                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma8, serial1);
1241         } else if (info->line == 2) {
1242                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma2);
1243                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma2, serial2);
1244         } else if (info->line == 3) {
1245                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma4);
1246                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma4, serial3);
1247         }
1248         *R_GEN_CONFIG = genconfig_shadow;
1249         local_irq_restore(flags);
1250 }
1251
1252 static void e100_disable_rxdma_channel(struct e100_serial *info)
1253 {
1254         unsigned long flags;
1255
1256         /* Disable input DMA channel for the serial port in question
1257          * ( set to something other than serialX)
1258          */
1259         local_irq_save(flags);
1260         if (info->line == 0) {
1261                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma7)) ==
1262                     IO_STATE(R_GEN_CONFIG, dma7, serial0)) {
1263                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma7);
1264                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma7, unused);
1265                 }
1266         } else if (info->line == 1) {
1267                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma9)) ==
1268                     IO_STATE(R_GEN_CONFIG, dma9, serial1)) {
1269                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma9);
1270                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma9, usb);
1271                 }
1272         } else if (info->line == 2) {
1273                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma3)) ==
1274                     IO_STATE(R_GEN_CONFIG, dma3, serial2)) {
1275                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma3);
1276                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma3, par0);
1277                 }
1278         } else if (info->line == 3) {
1279                 if ((genconfig_shadow & IO_MASK(R_GEN_CONFIG, dma5)) ==
1280                     IO_STATE(R_GEN_CONFIG, dma5, serial3)) {
1281                         genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma5);
1282                         genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma5, par1);
1283                 }
1284         }
1285         *R_GEN_CONFIG = genconfig_shadow;
1286         local_irq_restore(flags);
1287 }
1288
1289
1290 static void e100_enable_rxdma_channel(struct e100_serial *info)
1291 {
1292         unsigned long flags;
1293
1294         local_irq_save(flags);
1295         /* Enable input DMA channel for the serial port in question */
1296         if (info->line == 0) {
1297                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma7);
1298                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma7, serial0);
1299         } else if (info->line == 1) {
1300                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma9);
1301                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma9, serial1);
1302         } else if (info->line == 2) {
1303                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma3);
1304                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma3, serial2);
1305         } else if (info->line == 3) {
1306                 genconfig_shadow &=  ~IO_MASK(R_GEN_CONFIG, dma5);
1307                 genconfig_shadow |= IO_STATE(R_GEN_CONFIG, dma5, serial3);
1308         }
1309         *R_GEN_CONFIG = genconfig_shadow;
1310         local_irq_restore(flags);
1311 }
1312
1313 #ifdef SERIAL_HANDLE_EARLY_ERRORS
1314 /* in order to detect and fix errors on the first byte
1315    we have to use the serial interrupts as well. */
1316
1317 static inline void
1318 e100_disable_serial_data_irq(struct e100_serial *info)
1319 {
1320 #ifdef SERIAL_DEBUG_INTR
1321         printk("ser_irq(%d): 0\n",info->line);
1322 #endif
1323         DINTR1(DEBUG_LOG(info->line,"IRQ disable data_irq %i\n", info->line));
1324         *R_IRQ_MASK1_CLR = (1U << (8+2*info->line));
1325 }
1326
1327 static inline void
1328 e100_enable_serial_data_irq(struct e100_serial *info)
1329 {
1330 #ifdef SERIAL_DEBUG_INTR
1331         printk("ser_irq(%d): 1\n",info->line);
1332         printk("**** %d = %d\n",
1333                (8+2*info->line),
1334                (1U << (8+2*info->line)));
1335 #endif
1336         DINTR1(DEBUG_LOG(info->line,"IRQ enable data_irq %i\n", info->line));
1337         *R_IRQ_MASK1_SET = (1U << (8+2*info->line));
1338 }
1339 #endif
1340
1341 static inline void
1342 e100_disable_serial_tx_ready_irq(struct e100_serial *info)
1343 {
1344 #ifdef SERIAL_DEBUG_INTR
1345         printk("ser_tx_irq(%d): 0\n",info->line);
1346 #endif
1347         DINTR1(DEBUG_LOG(info->line,"IRQ disable ready_irq %i\n", info->line));
1348         *R_IRQ_MASK1_CLR = (1U << (8+1+2*info->line));
1349 }
1350
1351 static inline void
1352 e100_enable_serial_tx_ready_irq(struct e100_serial *info)
1353 {
1354 #ifdef SERIAL_DEBUG_INTR
1355         printk("ser_tx_irq(%d): 1\n",info->line);
1356         printk("**** %d = %d\n",
1357                (8+1+2*info->line),
1358                (1U << (8+1+2*info->line)));
1359 #endif
1360         DINTR2(DEBUG_LOG(info->line,"IRQ enable ready_irq %i\n", info->line));
1361         *R_IRQ_MASK1_SET = (1U << (8+1+2*info->line));
1362 }
1363
1364 static inline void e100_enable_rx_irq(struct e100_serial *info)
1365 {
1366         if (info->uses_dma_in)
1367                 e100_enable_rxdma_irq(info);
1368         else
1369                 e100_enable_serial_data_irq(info);
1370 }
1371 static inline void e100_disable_rx_irq(struct e100_serial *info)
1372 {
1373         if (info->uses_dma_in)
1374                 e100_disable_rxdma_irq(info);
1375         else
1376                 e100_disable_serial_data_irq(info);
1377 }
1378
1379 #if defined(CONFIG_ETRAX_RS485)
1380 /* Enable RS-485 mode on selected port. This is UGLY. */
1381 static int
1382 e100_enable_rs485(struct tty_struct *tty, struct serial_rs485 *r)
1383 {
1384         struct e100_serial * info = (struct e100_serial *)tty->driver_data;
1385
1386 #if defined(CONFIG_ETRAX_RS485_ON_PA)
1387         *R_PORT_PA_DATA = port_pa_data_shadow |= (1 << rs485_pa_bit);
1388 #endif
1389 #if defined(CONFIG_ETRAX_RS485_ON_PORT_G)
1390         REG_SHADOW_SET(R_PORT_G_DATA,  port_g_data_shadow,
1391                        rs485_port_g_bit, 1);
1392 #endif
1393 #if defined(CONFIG_ETRAX_RS485_LTC1387)
1394         REG_SHADOW_SET(R_PORT_G_DATA, port_g_data_shadow,
1395                        CONFIG_ETRAX_RS485_LTC1387_DXEN_PORT_G_BIT, 1);
1396         REG_SHADOW_SET(R_PORT_G_DATA, port_g_data_shadow,
1397                        CONFIG_ETRAX_RS485_LTC1387_RXEN_PORT_G_BIT, 1);
1398 #endif
1399
1400         info->rs485 = *r;
1401
1402         /* Maximum delay before RTS equal to 1000 */
1403         if (info->rs485.delay_rts_before_send >= 1000)
1404                 info->rs485.delay_rts_before_send = 1000;
1405
1406 /*      printk("rts: on send = %i, after = %i, enabled = %i",
1407                     info->rs485.rts_on_send,
1408                     info->rs485.rts_after_sent,
1409                     info->rs485.enabled
1410         );
1411 */
1412         return 0;
1413 }
1414
1415 static int
1416 e100_write_rs485(struct tty_struct *tty,
1417                  const unsigned char *buf, int count)
1418 {
1419         struct e100_serial * info = (struct e100_serial *)tty->driver_data;
1420         int old_value = (info->rs485.flags) & SER_RS485_ENABLED;
1421
1422         /* rs485 is always implicitly enabled if we're using the ioctl()
1423          * but it doesn't have to be set in the serial_rs485
1424          * (to be backward compatible with old apps)
1425          * So we store, set and restore it.
1426          */
1427         info->rs485.flags |= SER_RS485_ENABLED;
1428         /* rs_write now deals with RS485 if enabled */
1429         count = rs_write(tty, buf, count);
1430         if (!old_value)
1431                 info->rs485.flags &= ~(SER_RS485_ENABLED);
1432         return count;
1433 }
1434
1435 #ifdef CONFIG_ETRAX_FAST_TIMER
1436 /* Timer function to toggle RTS when using FAST_TIMER */
1437 static void rs485_toggle_rts_timer_function(unsigned long data)
1438 {
1439         struct e100_serial *info = (struct e100_serial *)data;
1440
1441         fast_timers_rs485[info->line].function = NULL;
1442         e100_rts(info, (info->rs485.flags & SER_RS485_RTS_AFTER_SEND));
1443 #if defined(CONFIG_ETRAX_RS485_DISABLE_RECEIVER)
1444         e100_enable_rx(info);
1445         e100_enable_rx_irq(info);
1446 #endif
1447 }
1448 #endif
1449 #endif /* CONFIG_ETRAX_RS485 */
1450
1451 /*
1452  * ------------------------------------------------------------
1453  * rs_stop() and rs_start()
1454  *
1455  * This routines are called before setting or resetting tty->stopped.
1456  * They enable or disable transmitter using the XOFF registers, as necessary.
1457  * ------------------------------------------------------------
1458  */
1459
1460 static void
1461 rs_stop(struct tty_struct *tty)
1462 {
1463         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
1464         if (info) {
1465                 unsigned long flags;
1466                 unsigned long xoff;
1467
1468                 local_irq_save(flags);
1469                 DFLOW(DEBUG_LOG(info->line, "XOFF rs_stop xmit %i\n",
1470                                 CIRC_CNT(info->xmit.head,
1471                                          info->xmit.tail,SERIAL_XMIT_SIZE)));
1472
1473                 xoff = IO_FIELD(R_SERIAL0_XOFF, xoff_char,
1474                                 STOP_CHAR(info->port.tty));
1475                 xoff |= IO_STATE(R_SERIAL0_XOFF, tx_stop, stop);
1476                 if (tty->termios->c_iflag & IXON ) {
1477                         xoff |= IO_STATE(R_SERIAL0_XOFF, auto_xoff, enable);
1478                 }
1479
1480                 *((unsigned long *)&info->ioport[REG_XOFF]) = xoff;
1481                 local_irq_restore(flags);
1482         }
1483 }
1484
1485 static void
1486 rs_start(struct tty_struct *tty)
1487 {
1488         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
1489         if (info) {
1490                 unsigned long flags;
1491                 unsigned long xoff;
1492
1493                 local_irq_save(flags);
1494                 DFLOW(DEBUG_LOG(info->line, "XOFF rs_start xmit %i\n",
1495                                 CIRC_CNT(info->xmit.head,
1496                                          info->xmit.tail,SERIAL_XMIT_SIZE)));
1497                 xoff = IO_FIELD(R_SERIAL0_XOFF, xoff_char, STOP_CHAR(tty));
1498                 xoff |= IO_STATE(R_SERIAL0_XOFF, tx_stop, enable);
1499                 if (tty->termios->c_iflag & IXON ) {
1500                         xoff |= IO_STATE(R_SERIAL0_XOFF, auto_xoff, enable);
1501                 }
1502
1503                 *((unsigned long *)&info->ioport[REG_XOFF]) = xoff;
1504                 if (!info->uses_dma_out &&
1505                     info->xmit.head != info->xmit.tail && info->xmit.buf)
1506                         e100_enable_serial_tx_ready_irq(info);
1507
1508                 local_irq_restore(flags);
1509         }
1510 }
1511
1512 /*
1513  * ----------------------------------------------------------------------
1514  *
1515  * Here starts the interrupt handling routines.  All of the following
1516  * subroutines are declared as inline and are folded into
1517  * rs_interrupt().  They were separated out for readability's sake.
1518  *
1519  * Note: rs_interrupt() is a "fast" interrupt, which means that it
1520  * runs with interrupts turned off.  People who may want to modify
1521  * rs_interrupt() should try to keep the interrupt handler as fast as
1522  * possible.  After you are done making modifications, it is not a bad
1523  * idea to do:
1524  *
1525  * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
1526  *
1527  * and look at the resulting assemble code in serial.s.
1528  *
1529  *                              - Ted Ts'o (tytso@mit.edu), 7-Mar-93
1530  * -----------------------------------------------------------------------
1531  */
1532
1533 /*
1534  * This routine is used by the interrupt handler to schedule
1535  * processing in the software interrupt portion of the driver.
1536  */
1537 static void rs_sched_event(struct e100_serial *info, int event)
1538 {
1539         if (info->event & (1 << event))
1540                 return;
1541         info->event |= 1 << event;
1542         schedule_work(&info->work);
1543 }
1544
1545 /* The output DMA channel is free - use it to send as many chars as possible
1546  * NOTES:
1547  *   We don't pay attention to info->x_char, which means if the TTY wants to
1548  *   use XON/XOFF it will set info->x_char but we won't send any X char!
1549  *
1550  *   To implement this, we'd just start a DMA send of 1 byte pointing at a
1551  *   buffer containing the X char, and skip updating xmit. We'd also have to
1552  *   check if the last sent char was the X char when we enter this function
1553  *   the next time, to avoid updating xmit with the sent X value.
1554  */
1555
1556 static void
1557 transmit_chars_dma(struct e100_serial *info)
1558 {
1559         unsigned int c, sentl;
1560         struct etrax_dma_descr *descr;
1561
1562 #ifdef CONFIG_SVINTO_SIM
1563         /* This will output too little if tail is not 0 always since
1564          * we don't reloop to send the other part. Anyway this SHOULD be a
1565          * no-op - transmit_chars_dma would never really be called during sim
1566          * since rs_write does not write into the xmit buffer then.
1567          */
1568         if (info->xmit.tail)
1569                 printk("Error in serial.c:transmit_chars-dma(), tail!=0\n");
1570         if (info->xmit.head != info->xmit.tail) {
1571                 SIMCOUT(info->xmit.buf + info->xmit.tail,
1572                         CIRC_CNT(info->xmit.head,
1573                                  info->xmit.tail,
1574                                  SERIAL_XMIT_SIZE));
1575                 info->xmit.head = info->xmit.tail;  /* move back head */
1576                 info->tr_running = 0;
1577         }
1578         return;
1579 #endif
1580         /* acknowledge both dma_descr and dma_eop irq in R_DMA_CHx_CLR_INTR */
1581         *info->oclrintradr =
1582                 IO_STATE(R_DMA_CH6_CLR_INTR, clr_descr, do) |
1583                 IO_STATE(R_DMA_CH6_CLR_INTR, clr_eop, do);
1584
1585 #ifdef SERIAL_DEBUG_INTR
1586         if (info->line == SERIAL_DEBUG_LINE)
1587                 printk("tc\n");
1588 #endif
1589         if (!info->tr_running) {
1590                 /* weirdo... we shouldn't get here! */
1591                 printk(KERN_WARNING "Achtung: transmit_chars_dma with !tr_running\n");
1592                 return;
1593         }
1594
1595         descr = &info->tr_descr;
1596
1597         /* first get the amount of bytes sent during the last DMA transfer,
1598            and update xmit accordingly */
1599
1600         /* if the stop bit was not set, all data has been sent */
1601         if (!(descr->status & d_stop)) {
1602                 sentl = descr->sw_len;
1603         } else
1604                 /* otherwise we find the amount of data sent here */
1605                 sentl = descr->hw_len;
1606
1607         DFLOW(DEBUG_LOG(info->line, "TX %i done\n", sentl));
1608
1609         /* update stats */
1610         info->icount.tx += sentl;
1611
1612         /* update xmit buffer */
1613         info->xmit.tail = (info->xmit.tail + sentl) & (SERIAL_XMIT_SIZE - 1);
1614
1615         /* if there is only a few chars left in the buf, wake up the blocked
1616            write if any */
1617         if (CIRC_CNT(info->xmit.head,
1618                      info->xmit.tail,
1619                      SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
1620                 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
1621
1622         /* find out the largest amount of consecutive bytes we want to send now */
1623
1624         c = CIRC_CNT_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
1625
1626         /* Don't send all in one DMA transfer - divide it so we wake up
1627          * application before all is sent
1628          */
1629
1630         if (c >= 4*WAKEUP_CHARS)
1631                 c = c/2;
1632
1633         if (c <= 0) {
1634                 /* our job here is done, don't schedule any new DMA transfer */
1635                 info->tr_running = 0;
1636
1637 #if defined(CONFIG_ETRAX_RS485) && defined(CONFIG_ETRAX_FAST_TIMER)
1638                 if (info->rs485.flags & SER_RS485_ENABLED) {
1639                         /* Set a short timer to toggle RTS */
1640                         start_one_shot_timer(&fast_timers_rs485[info->line],
1641                                              rs485_toggle_rts_timer_function,
1642                                              (unsigned long)info,
1643                                              info->char_time_usec*2,
1644                                              "RS-485");
1645                 }
1646 #endif /* RS485 */
1647                 return;
1648         }
1649
1650         /* ok we can schedule a dma send of c chars starting at info->xmit.tail */
1651         /* set up the descriptor correctly for output */
1652         DFLOW(DEBUG_LOG(info->line, "TX %i\n", c));
1653         descr->ctrl = d_int | d_eol | d_wait; /* Wait needed for tty_wait_until_sent() */
1654         descr->sw_len = c;
1655         descr->buf = virt_to_phys(info->xmit.buf + info->xmit.tail);
1656         descr->status = 0;
1657
1658         *info->ofirstadr = virt_to_phys(descr); /* write to R_DMAx_FIRST */
1659         *info->ocmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, start);
1660
1661         /* DMA is now running (hopefully) */
1662 } /* transmit_chars_dma */
1663
1664 static void
1665 start_transmit(struct e100_serial *info)
1666 {
1667 #if 0
1668         if (info->line == SERIAL_DEBUG_LINE)
1669                 printk("x\n");
1670 #endif
1671
1672         info->tr_descr.sw_len = 0;
1673         info->tr_descr.hw_len = 0;
1674         info->tr_descr.status = 0;
1675         info->tr_running = 1;
1676         if (info->uses_dma_out)
1677                 transmit_chars_dma(info);
1678         else
1679                 e100_enable_serial_tx_ready_irq(info);
1680 } /* start_transmit */
1681
1682 #ifdef CONFIG_ETRAX_SERIAL_FAST_TIMER
1683 static int serial_fast_timer_started = 0;
1684 static int serial_fast_timer_expired = 0;
1685 static void flush_timeout_function(unsigned long data);
1686 #define START_FLUSH_FAST_TIMER_TIME(info, string, usec) {\
1687   unsigned long timer_flags; \
1688   local_irq_save(timer_flags); \
1689   if (fast_timers[info->line].function == NULL) { \
1690     serial_fast_timer_started++; \
1691     TIMERD(DEBUG_LOG(info->line, "start_timer %i ", info->line)); \
1692     TIMERD(DEBUG_LOG(info->line, "num started: %i\n", serial_fast_timer_started)); \
1693     start_one_shot_timer(&fast_timers[info->line], \
1694                          flush_timeout_function, \
1695                          (unsigned long)info, \
1696                          (usec), \
1697                          string); \
1698   } \
1699   else { \
1700     TIMERD(DEBUG_LOG(info->line, "timer %i already running\n", info->line)); \
1701   } \
1702   local_irq_restore(timer_flags); \
1703 }
1704 #define START_FLUSH_FAST_TIMER(info, string) START_FLUSH_FAST_TIMER_TIME(info, string, info->flush_time_usec)
1705
1706 #else
1707 #define START_FLUSH_FAST_TIMER_TIME(info, string, usec)
1708 #define START_FLUSH_FAST_TIMER(info, string)
1709 #endif
1710
1711 static struct etrax_recv_buffer *
1712 alloc_recv_buffer(unsigned int size)
1713 {
1714         struct etrax_recv_buffer *buffer;
1715
1716         if (!(buffer = kmalloc(sizeof *buffer + size, GFP_ATOMIC)))
1717                 return NULL;
1718
1719         buffer->next = NULL;
1720         buffer->length = 0;
1721         buffer->error = TTY_NORMAL;
1722
1723         return buffer;
1724 }
1725
1726 static void
1727 append_recv_buffer(struct e100_serial *info, struct etrax_recv_buffer *buffer)
1728 {
1729         unsigned long flags;
1730
1731         local_irq_save(flags);
1732
1733         if (!info->first_recv_buffer)
1734                 info->first_recv_buffer = buffer;
1735         else
1736                 info->last_recv_buffer->next = buffer;
1737
1738         info->last_recv_buffer = buffer;
1739
1740         info->recv_cnt += buffer->length;
1741         if (info->recv_cnt > info->max_recv_cnt)
1742                 info->max_recv_cnt = info->recv_cnt;
1743
1744         local_irq_restore(flags);
1745 }
1746
1747 static int
1748 add_char_and_flag(struct e100_serial *info, unsigned char data, unsigned char flag)
1749 {
1750         struct etrax_recv_buffer *buffer;
1751         if (info->uses_dma_in) {
1752                 if (!(buffer = alloc_recv_buffer(4)))
1753                         return 0;
1754
1755                 buffer->length = 1;
1756                 buffer->error = flag;
1757                 buffer->buffer[0] = data;
1758
1759                 append_recv_buffer(info, buffer);
1760
1761                 info->icount.rx++;
1762         } else {
1763                 struct tty_struct *tty = info->port.tty;
1764                 tty_insert_flip_char(tty, data, flag);
1765                 info->icount.rx++;
1766         }
1767
1768         return 1;
1769 }
1770
1771 static unsigned int handle_descr_data(struct e100_serial *info,
1772                                       struct etrax_dma_descr *descr,
1773                                       unsigned int recvl)
1774 {
1775         struct etrax_recv_buffer *buffer = phys_to_virt(descr->buf) - sizeof *buffer;
1776
1777         if (info->recv_cnt + recvl > 65536) {
1778                 printk(KERN_WARNING
1779                        "%s: Too much pending incoming serial data! Dropping %u bytes.\n", __func__, recvl);
1780                 return 0;
1781         }
1782
1783         buffer->length = recvl;
1784
1785         if (info->errorcode == ERRCODE_SET_BREAK)
1786                 buffer->error = TTY_BREAK;
1787         info->errorcode = 0;
1788
1789         append_recv_buffer(info, buffer);
1790
1791         if (!(buffer = alloc_recv_buffer(SERIAL_DESCR_BUF_SIZE)))
1792                 panic("%s: Failed to allocate memory for receive buffer!\n", __func__);
1793
1794         descr->buf = virt_to_phys(buffer->buffer);
1795
1796         return recvl;
1797 }
1798
1799 static unsigned int handle_all_descr_data(struct e100_serial *info)
1800 {
1801         struct etrax_dma_descr *descr;
1802         unsigned int recvl;
1803         unsigned int ret = 0;
1804
1805         while (1)
1806         {
1807                 descr = &info->rec_descr[info->cur_rec_descr];
1808
1809                 if (descr == phys_to_virt(*info->idescradr))
1810                         break;
1811
1812                 if (++info->cur_rec_descr == SERIAL_RECV_DESCRIPTORS)
1813                         info->cur_rec_descr = 0;
1814
1815                 /* find out how many bytes were read */
1816
1817                 /* if the eop bit was not set, all data has been received */
1818                 if (!(descr->status & d_eop)) {
1819                         recvl = descr->sw_len;
1820                 } else {
1821                         /* otherwise we find the amount of data received here */
1822                         recvl = descr->hw_len;
1823                 }
1824
1825                 /* Reset the status information */
1826                 descr->status = 0;
1827
1828                 DFLOW(  DEBUG_LOG(info->line, "RX %lu\n", recvl);
1829                         if (info->port.tty->stopped) {
1830                                 unsigned char *buf = phys_to_virt(descr->buf);
1831                                 DEBUG_LOG(info->line, "rx 0x%02X\n", buf[0]);
1832                                 DEBUG_LOG(info->line, "rx 0x%02X\n", buf[1]);
1833                                 DEBUG_LOG(info->line, "rx 0x%02X\n", buf[2]);
1834                         }
1835                         );
1836
1837                 /* update stats */
1838                 info->icount.rx += recvl;
1839
1840                 ret += handle_descr_data(info, descr, recvl);
1841         }
1842
1843         return ret;
1844 }
1845
1846 static void receive_chars_dma(struct e100_serial *info)
1847 {
1848         struct tty_struct *tty;
1849         unsigned char rstat;
1850
1851 #ifdef CONFIG_SVINTO_SIM
1852         /* No receive in the simulator.  Will probably be when the rest of
1853          * the serial interface works, and this piece will just be removed.
1854          */
1855         return;
1856 #endif
1857
1858         /* Acknowledge both dma_descr and dma_eop irq in R_DMA_CHx_CLR_INTR */
1859         *info->iclrintradr =
1860                 IO_STATE(R_DMA_CH6_CLR_INTR, clr_descr, do) |
1861                 IO_STATE(R_DMA_CH6_CLR_INTR, clr_eop, do);
1862
1863         tty = info->port.tty;
1864         if (!tty) /* Something wrong... */
1865                 return;
1866
1867 #ifdef SERIAL_HANDLE_EARLY_ERRORS
1868         if (info->uses_dma_in)
1869                 e100_enable_serial_data_irq(info);
1870 #endif
1871
1872         if (info->errorcode == ERRCODE_INSERT_BREAK)
1873                 add_char_and_flag(info, '\0', TTY_BREAK);
1874
1875         handle_all_descr_data(info);
1876
1877         /* Read the status register to detect errors */
1878         rstat = info->ioport[REG_STATUS];
1879         if (rstat & IO_MASK(R_SERIAL0_STATUS, xoff_detect) ) {
1880                 DFLOW(DEBUG_LOG(info->line, "XOFF detect stat %x\n", rstat));
1881         }
1882
1883         if (rstat & SER_ERROR_MASK) {
1884                 /* If we got an error, we must reset it by reading the
1885                  * data_in field
1886                  */
1887                 unsigned char data = info->ioport[REG_DATA];
1888
1889                 PROCSTAT(ser_stat[info->line].errors_cnt++);
1890                 DEBUG_LOG(info->line, "#dERR: s d 0x%04X\n",
1891                           ((rstat & SER_ERROR_MASK) << 8) | data);
1892
1893                 if (rstat & SER_PAR_ERR_MASK)
1894                         add_char_and_flag(info, data, TTY_PARITY);
1895                 else if (rstat & SER_OVERRUN_MASK)
1896                         add_char_and_flag(info, data, TTY_OVERRUN);
1897                 else if (rstat & SER_FRAMING_ERR_MASK)
1898                         add_char_and_flag(info, data, TTY_FRAME);
1899         }
1900
1901         START_FLUSH_FAST_TIMER(info, "receive_chars");
1902
1903         /* Restart the receiving DMA */
1904         *info->icmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, restart);
1905 }
1906
1907 static int start_recv_dma(struct e100_serial *info)
1908 {
1909         struct etrax_dma_descr *descr = info->rec_descr;
1910         struct etrax_recv_buffer *buffer;
1911         int i;
1912
1913         /* Set up the receiving descriptors */
1914         for (i = 0; i < SERIAL_RECV_DESCRIPTORS; i++) {
1915                 if (!(buffer = alloc_recv_buffer(SERIAL_DESCR_BUF_SIZE)))
1916                         panic("%s: Failed to allocate memory for receive buffer!\n", __func__);
1917
1918                 descr[i].ctrl = d_int;
1919                 descr[i].buf = virt_to_phys(buffer->buffer);
1920                 descr[i].sw_len = SERIAL_DESCR_BUF_SIZE;
1921                 descr[i].hw_len = 0;
1922                 descr[i].status = 0;
1923                 descr[i].next = virt_to_phys(&descr[i+1]);
1924         }
1925
1926         /* Link the last descriptor to the first */
1927         descr[i-1].next = virt_to_phys(&descr[0]);
1928
1929         /* Start with the first descriptor in the list */
1930         info->cur_rec_descr = 0;
1931
1932         /* Start the DMA */
1933         *info->ifirstadr = virt_to_phys(&descr[info->cur_rec_descr]);
1934         *info->icmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, start);
1935
1936         /* Input DMA should be running now */
1937         return 1;
1938 }
1939
1940 static void
1941 start_receive(struct e100_serial *info)
1942 {
1943 #ifdef CONFIG_SVINTO_SIM
1944         /* No receive in the simulator.  Will probably be when the rest of
1945          * the serial interface works, and this piece will just be removed.
1946          */
1947         return;
1948 #endif
1949         if (info->uses_dma_in) {
1950                 /* reset the input dma channel to be sure it works */
1951
1952                 *info->icmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, reset);
1953                 while (IO_EXTRACT(R_DMA_CH6_CMD, cmd, *info->icmdadr) ==
1954                        IO_STATE_VALUE(R_DMA_CH6_CMD, cmd, reset));
1955
1956                 start_recv_dma(info);
1957         }
1958 }
1959
1960
1961 /* the bits in the MASK2 register are laid out like this:
1962    DMAI_EOP DMAI_DESCR DMAO_EOP DMAO_DESCR
1963    where I is the input channel and O is the output channel for the port.
1964    info->irq is the bit number for the DMAO_DESCR so to check the others we
1965    shift info->irq to the left.
1966 */
1967
1968 /* dma output channel interrupt handler
1969    this interrupt is called from DMA2(ser2), DMA4(ser3), DMA6(ser0) or
1970    DMA8(ser1) when they have finished a descriptor with the intr flag set.
1971 */
1972
1973 static irqreturn_t
1974 tr_interrupt(int irq, void *dev_id)
1975 {
1976         struct e100_serial *info;
1977         unsigned long ireg;
1978         int i;
1979         int handled = 0;
1980
1981 #ifdef CONFIG_SVINTO_SIM
1982         /* No receive in the simulator.  Will probably be when the rest of
1983          * the serial interface works, and this piece will just be removed.
1984          */
1985         {
1986                 const char *s = "What? tr_interrupt in simulator??\n";
1987                 SIMCOUT(s,strlen(s));
1988         }
1989         return IRQ_HANDLED;
1990 #endif
1991
1992         /* find out the line that caused this irq and get it from rs_table */
1993
1994         ireg = *R_IRQ_MASK2_RD;  /* get the active irq bits for the dma channels */
1995
1996         for (i = 0; i < NR_PORTS; i++) {
1997                 info = rs_table + i;
1998                 if (!info->enabled || !info->uses_dma_out)
1999                         continue;
2000                 /* check for dma_descr (don't need to check for dma_eop in output dma for serial */
2001                 if (ireg & info->irq) {
2002                         handled = 1;
2003                         /* we can send a new dma bunch. make it so. */
2004                         DINTR2(DEBUG_LOG(info->line, "tr_interrupt %i\n", i));
2005                         /* Read jiffies_usec first,
2006                          * we want this time to be as late as possible
2007                          */
2008                         PROCSTAT(ser_stat[info->line].tx_dma_ints++);
2009                         info->last_tx_active_usec = GET_JIFFIES_USEC();
2010                         info->last_tx_active = jiffies;
2011                         transmit_chars_dma(info);
2012                 }
2013
2014                 /* FIXME: here we should really check for a change in the
2015                    status lines and if so call status_handle(info) */
2016         }
2017         return IRQ_RETVAL(handled);
2018 } /* tr_interrupt */
2019
2020 /* dma input channel interrupt handler */
2021
2022 static irqreturn_t
2023 rec_interrupt(int irq, void *dev_id)
2024 {
2025         struct e100_serial *info;
2026         unsigned long ireg;
2027         int i;
2028         int handled = 0;
2029
2030 #ifdef CONFIG_SVINTO_SIM
2031         /* No receive in the simulator.  Will probably be when the rest of
2032          * the serial interface works, and this piece will just be removed.
2033          */
2034         {
2035                 const char *s = "What? rec_interrupt in simulator??\n";
2036                 SIMCOUT(s,strlen(s));
2037         }
2038         return IRQ_HANDLED;
2039 #endif
2040
2041         /* find out the line that caused this irq and get it from rs_table */
2042
2043         ireg = *R_IRQ_MASK2_RD;  /* get the active irq bits for the dma channels */
2044
2045         for (i = 0; i < NR_PORTS; i++) {
2046                 info = rs_table + i;
2047                 if (!info->enabled || !info->uses_dma_in)
2048                         continue;
2049                 /* check for both dma_eop and dma_descr for the input dma channel */
2050                 if (ireg & ((info->irq << 2) | (info->irq << 3))) {
2051                         handled = 1;
2052                         /* we have received something */
2053                         receive_chars_dma(info);
2054                 }
2055
2056                 /* FIXME: here we should really check for a change in the
2057                    status lines and if so call status_handle(info) */
2058         }
2059         return IRQ_RETVAL(handled);
2060 } /* rec_interrupt */
2061
2062 static int force_eop_if_needed(struct e100_serial *info)
2063 {
2064         /* We check data_avail bit to determine if data has
2065          * arrived since last time
2066          */
2067         unsigned char rstat = info->ioport[REG_STATUS];
2068
2069         /* error or datavail? */
2070         if (rstat & SER_ERROR_MASK) {
2071                 /* Some error has occurred. If there has been valid data, an
2072                  * EOP interrupt will be made automatically. If no data, the
2073                  * normal ser_interrupt should be enabled and handle it.
2074                  * So do nothing!
2075                  */
2076                 DEBUG_LOG(info->line, "timeout err: rstat 0x%03X\n",
2077                           rstat | (info->line << 8));
2078                 return 0;
2079         }
2080
2081         if (rstat & SER_DATA_AVAIL_MASK) {
2082                 /* Ok data, no error, count it */
2083                 TIMERD(DEBUG_LOG(info->line, "timeout: rstat 0x%03X\n",
2084                           rstat | (info->line << 8)));
2085                 /* Read data to clear status flags */
2086                 (void)info->ioport[REG_DATA];
2087
2088                 info->forced_eop = 0;
2089                 START_FLUSH_FAST_TIMER(info, "magic");
2090                 return 0;
2091         }
2092
2093         /* hit the timeout, force an EOP for the input
2094          * dma channel if we haven't already
2095          */
2096         if (!info->forced_eop) {
2097                 info->forced_eop = 1;
2098                 PROCSTAT(ser_stat[info->line].timeout_flush_cnt++);
2099                 TIMERD(DEBUG_LOG(info->line, "timeout EOP %i\n", info->line));
2100                 FORCE_EOP(info);
2101         }
2102
2103         return 1;
2104 }
2105
2106 static void flush_to_flip_buffer(struct e100_serial *info)
2107 {
2108         struct tty_struct *tty;
2109         struct etrax_recv_buffer *buffer;
2110         unsigned long flags;
2111
2112         local_irq_save(flags);
2113         tty = info->port.tty;
2114
2115         if (!tty) {
2116                 local_irq_restore(flags);
2117                 return;
2118         }
2119
2120         while ((buffer = info->first_recv_buffer) != NULL) {
2121                 unsigned int count = buffer->length;
2122
2123                 tty_insert_flip_string(tty, buffer->buffer, count);
2124                 info->recv_cnt -= count;
2125
2126                 if (count == buffer->length) {
2127                         info->first_recv_buffer = buffer->next;
2128                         kfree(buffer);
2129                 } else {
2130                         buffer->length -= count;
2131                         memmove(buffer->buffer, buffer->buffer + count, buffer->length);
2132                         buffer->error = TTY_NORMAL;
2133                 }
2134         }
2135
2136         if (!info->first_recv_buffer)
2137                 info->last_recv_buffer = NULL;
2138
2139         local_irq_restore(flags);
2140
2141         /* This includes a check for low-latency */
2142         tty_flip_buffer_push(tty);
2143 }
2144
2145 static void check_flush_timeout(struct e100_serial *info)
2146 {
2147         /* Flip what we've got (if we can) */
2148         flush_to_flip_buffer(info);
2149
2150         /* We might need to flip later, but not to fast
2151          * since the system is busy processing input... */
2152         if (info->first_recv_buffer)
2153                 START_FLUSH_FAST_TIMER_TIME(info, "flip", 2000);
2154
2155         /* Force eop last, since data might have come while we're processing
2156          * and if we started the slow timer above, we won't start a fast
2157          * below.
2158          */
2159         force_eop_if_needed(info);
2160 }
2161
2162 #ifdef CONFIG_ETRAX_SERIAL_FAST_TIMER
2163 static void flush_timeout_function(unsigned long data)
2164 {
2165         struct e100_serial *info = (struct e100_serial *)data;
2166
2167         fast_timers[info->line].function = NULL;
2168         serial_fast_timer_expired++;
2169         TIMERD(DEBUG_LOG(info->line, "flush_timout %i ", info->line));
2170         TIMERD(DEBUG_LOG(info->line, "num expired: %i\n", serial_fast_timer_expired));
2171         check_flush_timeout(info);
2172 }
2173
2174 #else
2175
2176 /* dma fifo/buffer timeout handler
2177    forces an end-of-packet for the dma input channel if no chars
2178    have been received for CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS/100 s.
2179 */
2180
2181 static struct timer_list flush_timer;
2182
2183 static void
2184 timed_flush_handler(unsigned long ptr)
2185 {
2186         struct e100_serial *info;
2187         int i;
2188
2189 #ifdef CONFIG_SVINTO_SIM
2190         return;
2191 #endif
2192
2193         for (i = 0; i < NR_PORTS; i++) {
2194                 info = rs_table + i;
2195                 if (info->uses_dma_in)
2196                         check_flush_timeout(info);
2197         }
2198
2199         /* restart flush timer */
2200         mod_timer(&flush_timer, jiffies + CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS);
2201 }
2202 #endif
2203
2204 #ifdef SERIAL_HANDLE_EARLY_ERRORS
2205
2206 /* If there is an error (ie break) when the DMA is running and
2207  * there are no bytes in the fifo the DMA is stopped and we get no
2208  * eop interrupt. Thus we have to monitor the first bytes on a DMA
2209  * transfer, and if it is without error we can turn the serial
2210  * interrupts off.
2211  */
2212
2213 /*
2214 BREAK handling on ETRAX 100:
2215 ETRAX will generate interrupt although there is no stop bit between the
2216 characters.
2217
2218 Depending on how long the break sequence is, the end of the breaksequence
2219 will look differently:
2220 | indicates start/end of a character.
2221
2222 B= Break character (0x00) with framing error.
2223 E= Error byte with parity error received after B characters.
2224 F= "Faked" valid byte received immediately after B characters.
2225 V= Valid byte
2226
2227 1.
2228     B          BL         ___________________________ V
2229 .._|__________|__________|                           |valid data |
2230
2231 Multiple frame errors with data == 0x00 (B),
2232 the timing matches up "perfectly" so no extra ending char is detected.
2233 The RXD pin is 1 in the last interrupt, in that case
2234 we set info->errorcode = ERRCODE_INSERT_BREAK, but we can't really
2235 know if another byte will come and this really is case 2. below
2236 (e.g F=0xFF or 0xFE)
2237 If RXD pin is 0 we can expect another character (see 2. below).
2238
2239
2240 2.
2241
2242     B          B          E or F__________________..__ V
2243 .._|__________|__________|______    |                 |valid data
2244                           "valid" or
2245                           parity error
2246
2247 Multiple frame errors with data == 0x00 (B),
2248 but the part of the break trigs is interpreted as a start bit (and possibly
2249 some 0 bits followed by a number of 1 bits and a stop bit).
2250 Depending on parity settings etc. this last character can be either
2251 a fake "valid" char (F) or have a parity error (E).
2252
2253 If the character is valid it will be put in the buffer,
2254 we set info->errorcode = ERRCODE_SET_BREAK so the receive interrupt
2255 will set the flags so the tty will handle it,
2256 if it's an error byte it will not be put in the buffer
2257 and we set info->errorcode = ERRCODE_INSERT_BREAK.
2258
2259 To distinguish a V byte in 1. from an F byte in 2. we keep a timestamp
2260 of the last faulty char (B) and compares it with the current time:
2261 If the time elapsed time is less then 2*char_time_usec we will assume
2262 it's a faked F char and not a Valid char and set
2263 info->errorcode = ERRCODE_SET_BREAK.
2264
2265 Flaws in the above solution:
2266 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2267 We use the timer to distinguish a F character from a V character,
2268 if a V character is to close after the break we might make the wrong decision.
2269
2270 TODO: The break will be delayed until an F or V character is received.
2271
2272 */
2273
2274 static
2275 struct e100_serial * handle_ser_rx_interrupt_no_dma(struct e100_serial *info)
2276 {
2277         unsigned long data_read;
2278         struct tty_struct *tty = info->port.tty;
2279
2280         if (!tty) {
2281                 printk("!NO TTY!\n");
2282                 return info;
2283         }
2284
2285         /* Read data and status at the same time */
2286         data_read = *((unsigned long *)&info->ioport[REG_DATA_STATUS32]);
2287 more_data:
2288         if (data_read & IO_MASK(R_SERIAL0_READ, xoff_detect) ) {
2289                 DFLOW(DEBUG_LOG(info->line, "XOFF detect\n", 0));
2290         }
2291         DINTR2(DEBUG_LOG(info->line, "ser_rx   %c\n", IO_EXTRACT(R_SERIAL0_READ, data_in, data_read)));
2292
2293         if (data_read & ( IO_MASK(R_SERIAL0_READ, framing_err) |
2294                           IO_MASK(R_SERIAL0_READ, par_err) |
2295                           IO_MASK(R_SERIAL0_READ, overrun) )) {
2296                 /* An error */
2297                 info->last_rx_active_usec = GET_JIFFIES_USEC();
2298                 info->last_rx_active = jiffies;
2299                 DINTR1(DEBUG_LOG(info->line, "ser_rx err stat_data %04X\n", data_read));
2300                 DLOG_INT_TRIG(
2301                 if (!log_int_trig1_pos) {
2302                         log_int_trig1_pos = log_int_pos;
2303                         log_int(rdpc(), 0, 0);
2304                 }
2305                 );
2306
2307
2308                 if ( ((data_read & IO_MASK(R_SERIAL0_READ, data_in)) == 0) &&
2309                      (data_read & IO_MASK(R_SERIAL0_READ, framing_err)) ) {
2310                         /* Most likely a break, but we get interrupts over and
2311                          * over again.
2312                          */
2313
2314                         if (!info->break_detected_cnt) {
2315                                 DEBUG_LOG(info->line, "#BRK start\n", 0);
2316                         }
2317                         if (data_read & IO_MASK(R_SERIAL0_READ, rxd)) {
2318                                 /* The RX pin is high now, so the break
2319                                  * must be over, but....
2320                                  * we can't really know if we will get another
2321                                  * last byte ending the break or not.
2322                                  * And we don't know if the byte (if any) will
2323                                  * have an error or look valid.
2324                                  */
2325                                 DEBUG_LOG(info->line, "# BL BRK\n", 0);
2326                                 info->errorcode = ERRCODE_INSERT_BREAK;
2327                         }
2328                         info->break_detected_cnt++;
2329                 } else {
2330                         /* The error does not look like a break, but could be
2331                          * the end of one
2332                          */
2333                         if (info->break_detected_cnt) {
2334                                 DEBUG_LOG(info->line, "EBRK %i\n", info->break_detected_cnt);
2335                                 info->errorcode = ERRCODE_INSERT_BREAK;
2336                         } else {
2337                                 unsigned char data = IO_EXTRACT(R_SERIAL0_READ,
2338                                         data_in, data_read);
2339                                 char flag = TTY_NORMAL;
2340                                 if (info->errorcode == ERRCODE_INSERT_BREAK) {
2341                                         struct tty_struct *tty = info->port.tty;
2342                                         tty_insert_flip_char(tty, 0, flag);
2343                                         info->icount.rx++;
2344                                 }
2345
2346                                 if (data_read & IO_MASK(R_SERIAL0_READ, par_err)) {
2347                                         info->icount.parity++;
2348                                         flag = TTY_PARITY;
2349                                 } else if (data_read & IO_MASK(R_SERIAL0_READ, overrun)) {
2350                                         info->icount.overrun++;
2351                                         flag = TTY_OVERRUN;
2352                                 } else if (data_read & IO_MASK(R_SERIAL0_READ, framing_err)) {
2353                                         info->icount.frame++;
2354                                         flag = TTY_FRAME;
2355                                 }
2356                                 tty_insert_flip_char(tty, data, flag);
2357                                 info->errorcode = 0;
2358                         }
2359                         info->break_detected_cnt = 0;
2360                 }
2361         } else if (data_read & IO_MASK(R_SERIAL0_READ, data_avail)) {
2362                 /* No error */
2363                 DLOG_INT_TRIG(
2364                 if (!log_int_trig1_pos) {
2365                         if (log_int_pos >= log_int_size) {
2366                                 log_int_pos = 0;
2367                         }
2368                         log_int_trig0_pos = log_int_pos;
2369                         log_int(rdpc(), 0, 0);
2370                 }
2371                 );
2372                 tty_insert_flip_char(tty,
2373                         IO_EXTRACT(R_SERIAL0_READ, data_in, data_read),
2374                         TTY_NORMAL);
2375         } else {
2376                 DEBUG_LOG(info->line, "ser_rx int but no data_avail  %08lX\n", data_read);
2377         }
2378
2379
2380         info->icount.rx++;
2381         data_read = *((unsigned long *)&info->ioport[REG_DATA_STATUS32]);
2382         if (data_read & IO_MASK(R_SERIAL0_READ, data_avail)) {
2383                 DEBUG_LOG(info->line, "ser_rx   %c in loop\n", IO_EXTRACT(R_SERIAL0_READ, data_in, data_read));
2384                 goto more_data;
2385         }
2386
2387         tty_flip_buffer_push(info->port.tty);
2388         return info;
2389 }
2390
2391 static struct e100_serial* handle_ser_rx_interrupt(struct e100_serial *info)
2392 {
2393         unsigned char rstat;
2394
2395 #ifdef SERIAL_DEBUG_INTR
2396         printk("Interrupt from serport %d\n", i);
2397 #endif
2398 /*      DEBUG_LOG(info->line, "ser_interrupt stat %03X\n", rstat | (i << 8)); */
2399         if (!info->uses_dma_in) {
2400                 return handle_ser_rx_interrupt_no_dma(info);
2401         }
2402         /* DMA is used */
2403         rstat = info->ioport[REG_STATUS];
2404         if (rstat & IO_MASK(R_SERIAL0_STATUS, xoff_detect) ) {
2405                 DFLOW(DEBUG_LOG(info->line, "XOFF detect\n", 0));
2406         }
2407
2408         if (rstat & SER_ERROR_MASK) {
2409                 unsigned char data;
2410
2411                 info->last_rx_active_usec = GET_JIFFIES_USEC();
2412                 info->last_rx_active = jiffies;
2413                 /* If we got an error, we must reset it by reading the
2414                  * data_in field
2415                  */
2416                 data = info->ioport[REG_DATA];
2417                 DINTR1(DEBUG_LOG(info->line, "ser_rx!  %c\n", data));
2418                 DINTR1(DEBUG_LOG(info->line, "ser_rx err stat %02X\n", rstat));
2419                 if (!data && (rstat & SER_FRAMING_ERR_MASK)) {
2420                         /* Most likely a break, but we get interrupts over and
2421                          * over again.
2422                          */
2423
2424                         if (!info->break_detected_cnt) {
2425                                 DEBUG_LOG(info->line, "#BRK start\n", 0);
2426                         }
2427                         if (rstat & SER_RXD_MASK) {
2428                                 /* The RX pin is high now, so the break
2429                                  * must be over, but....
2430                                  * we can't really know if we will get another
2431                                  * last byte ending the break or not.
2432                                  * And we don't know if the byte (if any) will
2433                                  * have an error or look valid.
2434                                  */
2435                                 DEBUG_LOG(info->line, "# BL BRK\n", 0);
2436                                 info->errorcode = ERRCODE_INSERT_BREAK;
2437                         }
2438                         info->break_detected_cnt++;
2439                 } else {
2440                         /* The error does not look like a break, but could be
2441                          * the end of one
2442                          */
2443                         if (info->break_detected_cnt) {
2444                                 DEBUG_LOG(info->line, "EBRK %i\n", info->break_detected_cnt);
2445                                 info->errorcode = ERRCODE_INSERT_BREAK;
2446                         } else {
2447                                 if (info->errorcode == ERRCODE_INSERT_BREAK) {
2448                                         info->icount.brk++;
2449                                         add_char_and_flag(info, '\0', TTY_BREAK);
2450                                 }
2451
2452                                 if (rstat & SER_PAR_ERR_MASK) {
2453                                         info->icount.parity++;
2454                                         add_char_and_flag(info, data, TTY_PARITY);
2455                                 } else if (rstat & SER_OVERRUN_MASK) {
2456                                         info->icount.overrun++;
2457                                         add_char_and_flag(info, data, TTY_OVERRUN);
2458                                 } else if (rstat & SER_FRAMING_ERR_MASK) {
2459                                         info->icount.frame++;
2460                                         add_char_and_flag(info, data, TTY_FRAME);
2461                                 }
2462
2463                                 info->errorcode = 0;
2464                         }
2465                         info->break_detected_cnt = 0;
2466                         DEBUG_LOG(info->line, "#iERR s d %04X\n",
2467                                   ((rstat & SER_ERROR_MASK) << 8) | data);
2468                 }
2469                 PROCSTAT(ser_stat[info->line].early_errors_cnt++);
2470         } else { /* It was a valid byte, now let the DMA do the rest */
2471                 unsigned long curr_time_u = GET_JIFFIES_USEC();
2472                 unsigned long curr_time = jiffies;
2473
2474                 if (info->break_detected_cnt) {
2475                         /* Detect if this character is a new valid char or the
2476                          * last char in a break sequence: If LSBits are 0 and
2477                          * MSBits are high AND the time is close to the
2478                          * previous interrupt we should discard it.
2479                          */
2480                         long elapsed_usec =
2481                           (curr_time - info->last_rx_active) * (1000000/HZ) +
2482                           curr_time_u - info->last_rx_active_usec;
2483                         if (elapsed_usec < 2*info->char_time_usec) {
2484                                 DEBUG_LOG(info->line, "FBRK %i\n", info->line);
2485                                 /* Report as BREAK (error) and let
2486                                  * receive_chars_dma() handle it
2487                                  */
2488                                 info->errorcode = ERRCODE_SET_BREAK;
2489                         } else {
2490                                 DEBUG_LOG(info->line, "Not end of BRK (V)%i\n", info->line);
2491                         }
2492                         DEBUG_LOG(info->line, "num brk %i\n", info->break_detected_cnt);
2493                 }
2494
2495 #ifdef SERIAL_DEBUG_INTR
2496                 printk("** OK, disabling ser_interrupts\n");
2497 #endif
2498                 e100_disable_serial_data_irq(info);
2499                 DINTR2(DEBUG_LOG(info->line, "ser_rx OK %d\n", info->line));
2500                 info->break_detected_cnt = 0;
2501
2502                 PROCSTAT(ser_stat[info->line].ser_ints_ok_cnt++);
2503         }
2504         /* Restarting the DMA never hurts */
2505         *info->icmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, restart);
2506         START_FLUSH_FAST_TIMER(info, "ser_int");
2507         return info;
2508 } /* handle_ser_rx_interrupt */
2509
2510 static void handle_ser_tx_interrupt(struct e100_serial *info)
2511 {
2512         unsigned long flags;
2513
2514         if (info->x_char) {
2515                 unsigned char rstat;
2516                 DFLOW(DEBUG_LOG(info->line, "tx_int: xchar 0x%02X\n", info->x_char));
2517                 local_irq_save(flags);
2518                 rstat = info->ioport[REG_STATUS];
2519                 DFLOW(DEBUG_LOG(info->line, "stat %x\n", rstat));
2520
2521                 info->ioport[REG_TR_DATA] = info->x_char;
2522                 info->icount.tx++;
2523                 info->x_char = 0;
2524                 /* We must enable since it is disabled in ser_interrupt */
2525                 e100_enable_serial_tx_ready_irq(info);
2526                 local_irq_restore(flags);
2527                 return;
2528         }
2529         if (info->uses_dma_out) {
2530                 unsigned char rstat;
2531                 int i;
2532                 /* We only use normal tx interrupt when sending x_char */
2533                 DFLOW(DEBUG_LOG(info->line, "tx_int: xchar sent\n", 0));
2534                 local_irq_save(flags);
2535                 rstat = info->ioport[REG_STATUS];
2536                 DFLOW(DEBUG_LOG(info->line, "stat %x\n", rstat));
2537                 e100_disable_serial_tx_ready_irq(info);
2538                 if (info->port.tty->stopped)
2539                         rs_stop(info->port.tty);
2540                 /* Enable the DMA channel and tell it to continue */
2541                 e100_enable_txdma_channel(info);
2542                 /* Wait 12 cycles before doing the DMA command */
2543                 for(i = 6;  i > 0; i--)
2544                         nop();
2545
2546                 *info->ocmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, continue);
2547                 local_irq_restore(flags);
2548                 return;
2549         }
2550         /* Normal char-by-char interrupt */
2551         if (info->xmit.head == info->xmit.tail
2552             || info->port.tty->stopped
2553             || info->port.tty->hw_stopped) {
2554                 DFLOW(DEBUG_LOG(info->line, "tx_int: stopped %i\n",
2555                                 info->port.tty->stopped));
2556                 e100_disable_serial_tx_ready_irq(info);
2557                 info->tr_running = 0;
2558                 return;
2559         }
2560         DINTR2(DEBUG_LOG(info->line, "tx_int %c\n", info->xmit.buf[info->xmit.tail]));
2561         /* Send a byte, rs485 timing is critical so turn of ints */
2562         local_irq_save(flags);
2563         info->ioport[REG_TR_DATA] = info->xmit.buf[info->xmit.tail];
2564         info->xmit.tail = (info->xmit.tail + 1) & (SERIAL_XMIT_SIZE-1);
2565         info->icount.tx++;
2566         if (info->xmit.head == info->xmit.tail) {
2567 #if defined(CONFIG_ETRAX_RS485) && defined(CONFIG_ETRAX_FAST_TIMER)
2568                 if (info->rs485.flags & SER_RS485_ENABLED) {
2569                         /* Set a short timer to toggle RTS */
2570                         start_one_shot_timer(&fast_timers_rs485[info->line],
2571                                              rs485_toggle_rts_timer_function,
2572                                              (unsigned long)info,
2573                                              info->char_time_usec*2,
2574                                              "RS-485");
2575                 }
2576 #endif /* RS485 */
2577                 info->last_tx_active_usec = GET_JIFFIES_USEC();
2578                 info->last_tx_active = jiffies;
2579                 e100_disable_serial_tx_ready_irq(info);
2580                 info->tr_running = 0;
2581                 DFLOW(DEBUG_LOG(info->line, "tx_int: stop2\n", 0));
2582         } else {
2583                 /* We must enable since it is disabled in ser_interrupt */
2584                 e100_enable_serial_tx_ready_irq(info);
2585         }
2586         local_irq_restore(flags);
2587
2588         if (CIRC_CNT(info->xmit.head,
2589                      info->xmit.tail,
2590                      SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
2591                 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
2592
2593 } /* handle_ser_tx_interrupt */
2594
2595 /* result of time measurements:
2596  * RX duration 54-60 us when doing something, otherwise 6-9 us
2597  * ser_int duration: just sending: 8-15 us normally, up to 73 us
2598  */
2599 static irqreturn_t
2600 ser_interrupt(int irq, void *dev_id)
2601 {
2602         static volatile int tx_started = 0;
2603         struct e100_serial *info;
2604         int i;
2605         unsigned long flags;
2606         unsigned long irq_mask1_rd;
2607         unsigned long data_mask = (1 << (8+2*0)); /* ser0 data_avail */
2608         int handled = 0;
2609         static volatile unsigned long reentered_ready_mask = 0;
2610
2611         local_irq_save(flags);
2612         irq_mask1_rd = *R_IRQ_MASK1_RD;
2613         /* First handle all rx interrupts with ints disabled */
2614         info = rs_table;
2615         irq_mask1_rd &= e100_ser_int_mask;
2616         for (i = 0; i < NR_PORTS; i++) {
2617                 /* Which line caused the data irq? */
2618                 if (irq_mask1_rd & data_mask) {
2619                         handled = 1;
2620                         handle_ser_rx_interrupt(info);
2621                 }
2622                 info += 1;
2623                 data_mask <<= 2;
2624         }
2625         /* Handle tx interrupts with interrupts enabled so we
2626          * can take care of new data interrupts while transmitting
2627          * We protect the tx part with the tx_started flag.
2628          * We disable the tr_ready interrupts we are about to handle and
2629          * unblock the serial interrupt so new serial interrupts may come.
2630          *
2631          * If we get a new interrupt:
2632          *  - it migth be due to synchronous serial ports.
2633          *  - serial irq will be blocked by general irq handler.
2634          *  - async data will be handled above (sync will be ignored).
2635          *  - tx_started flag will prevent us from trying to send again and
2636          *    we will exit fast - no need to unblock serial irq.
2637          *  - Next (sync) serial interrupt handler will be runned with
2638          *    disabled interrupt due to restore_flags() at end of function,
2639          *    so sync handler will not be preempted or reentered.
2640          */
2641         if (!tx_started) {
2642                 unsigned long ready_mask;
2643                 unsigned long
2644                 tx_started = 1;
2645                 /* Only the tr_ready interrupts left */
2646                 irq_mask1_rd &= (IO_MASK(R_IRQ_MASK1_RD, ser0_ready) |
2647                                  IO_MASK(R_IRQ_MASK1_RD, ser1_ready) |
2648                                  IO_MASK(R_IRQ_MASK1_RD, ser2_ready) |
2649                                  IO_MASK(R_IRQ_MASK1_RD, ser3_ready));
2650                 while (irq_mask1_rd) {
2651                         /* Disable those we are about to handle */
2652                         *R_IRQ_MASK1_CLR = irq_mask1_rd;
2653                         /* Unblock the serial interrupt */
2654                         *R_VECT_MASK_SET = IO_STATE(R_VECT_MASK_SET, serial, set);
2655
2656                         local_irq_enable();
2657                         ready_mask = (1 << (8+1+2*0)); /* ser0 tr_ready */
2658                         info = rs_table;
2659                         for (i = 0; i < NR_PORTS; i++) {
2660                                 /* Which line caused the ready irq? */
2661                                 if (irq_mask1_rd & ready_mask) {
2662                                         handled = 1;
2663                                         handle_ser_tx_interrupt(info);
2664                                 }
2665                                 info += 1;
2666                                 ready_mask <<= 2;
2667                         }
2668                         /* handle_ser_tx_interrupt enables tr_ready interrupts */
2669                         local_irq_disable();
2670                         /* Handle reentered TX interrupt */
2671                         irq_mask1_rd = reentered_ready_mask;
2672                 }
2673                 local_irq_disable();
2674                 tx_started = 0;
2675         } else {
2676                 unsigned long ready_mask;
2677                 ready_mask = irq_mask1_rd & (IO_MASK(R_IRQ_MASK1_RD, ser0_ready) |
2678                                              IO_MASK(R_IRQ_MASK1_RD, ser1_ready) |
2679                                              IO_MASK(R_IRQ_MASK1_RD, ser2_ready) |
2680                                              IO_MASK(R_IRQ_MASK1_RD, ser3_ready));
2681                 if (ready_mask) {
2682                         reentered_ready_mask |= ready_mask;
2683                         /* Disable those we are about to handle */
2684                         *R_IRQ_MASK1_CLR = ready_mask;
2685                         DFLOW(DEBUG_LOG(SERIAL_DEBUG_LINE, "ser_int reentered with TX %X\n", ready_mask));
2686                 }
2687         }
2688
2689         local_irq_restore(flags);
2690         return IRQ_RETVAL(handled);
2691 } /* ser_interrupt */
2692 #endif
2693
2694 /*
2695  * -------------------------------------------------------------------
2696  * Here ends the serial interrupt routines.
2697  * -------------------------------------------------------------------
2698  */
2699
2700 /*
2701  * This routine is used to handle the "bottom half" processing for the
2702  * serial driver, known also the "software interrupt" processing.
2703  * This processing is done at the kernel interrupt level, after the
2704  * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
2705  * is where time-consuming activities which can not be done in the
2706  * interrupt driver proper are done; the interrupt driver schedules
2707  * them using rs_sched_event(), and they get done here.
2708  */
2709 static void
2710 do_softint(struct work_struct *work)
2711 {
2712         struct e100_serial      *info;
2713         struct tty_struct       *tty;
2714
2715         info = container_of(work, struct e100_serial, work);
2716
2717         tty = info->port.tty;
2718         if (!tty)
2719                 return;
2720
2721         if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event))
2722                 tty_wakeup(tty);
2723 }
2724
2725 static int
2726 startup(struct e100_serial * info)
2727 {
2728         unsigned long flags;
2729         unsigned long xmit_page;
2730         int i;
2731
2732         xmit_page = get_zeroed_page(GFP_KERNEL);
2733         if (!xmit_page)
2734                 return -ENOMEM;
2735
2736         local_irq_save(flags);
2737
2738         /* if it was already initialized, skip this */
2739
2740         if (info->flags & ASYNC_INITIALIZED) {
2741                 local_irq_restore(flags);
2742                 free_page(xmit_page);
2743                 return 0;
2744         }
2745
2746         if (info->xmit.buf)
2747                 free_page(xmit_page);
2748         else
2749                 info->xmit.buf = (unsigned char *) xmit_page;
2750
2751 #ifdef SERIAL_DEBUG_OPEN
2752         printk("starting up ttyS%d (xmit_buf 0x%p)...\n", info->line, info->xmit.buf);
2753 #endif
2754
2755 #ifdef CONFIG_SVINTO_SIM
2756         /* Bits and pieces collected from below.  Better to have them
2757            in one ifdef:ed clause than to mix in a lot of ifdefs,
2758            right? */
2759         if (info->port.tty)
2760                 clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2761
2762         info->xmit.head = info->xmit.tail = 0;
2763         info->first_recv_buffer = info->last_recv_buffer = NULL;
2764         info->recv_cnt = info->max_recv_cnt = 0;
2765
2766         for (i = 0; i < SERIAL_RECV_DESCRIPTORS; i++)
2767                 info->rec_descr[i].buf = NULL;
2768
2769         /* No real action in the simulator, but may set info important
2770            to ioctl. */
2771         change_speed(info);
2772 #else
2773
2774         /*
2775          * Clear the FIFO buffers and disable them
2776          * (they will be reenabled in change_speed())
2777          */
2778
2779         /*
2780          * Reset the DMA channels and make sure their interrupts are cleared
2781          */
2782
2783         if (info->dma_in_enabled) {
2784                 info->uses_dma_in = 1;
2785                 e100_enable_rxdma_channel(info);
2786
2787                 *info->icmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, reset);
2788
2789                 /* Wait until reset cycle is complete */
2790                 while (IO_EXTRACT(R_DMA_CH6_CMD, cmd, *info->icmdadr) ==
2791                        IO_STATE_VALUE(R_DMA_CH6_CMD, cmd, reset));
2792
2793                 /* Make sure the irqs are cleared */
2794                 *info->iclrintradr =
2795                         IO_STATE(R_DMA_CH6_CLR_INTR, clr_descr, do) |
2796                         IO_STATE(R_DMA_CH6_CLR_INTR, clr_eop, do);
2797         } else {
2798                 e100_disable_rxdma_channel(info);
2799         }
2800
2801         if (info->dma_out_enabled) {
2802                 info->uses_dma_out = 1;
2803                 e100_enable_txdma_channel(info);
2804                 *info->ocmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, reset);
2805
2806                 while (IO_EXTRACT(R_DMA_CH6_CMD, cmd, *info->ocmdadr) ==
2807                        IO_STATE_VALUE(R_DMA_CH6_CMD, cmd, reset));
2808
2809                 /* Make sure the irqs are cleared */
2810                 *info->oclrintradr =
2811                         IO_STATE(R_DMA_CH6_CLR_INTR, clr_descr, do) |
2812                         IO_STATE(R_DMA_CH6_CLR_INTR, clr_eop, do);
2813         } else {
2814                 e100_disable_txdma_channel(info);
2815         }
2816
2817         if (info->port.tty)
2818                 clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2819
2820         info->xmit.head = info->xmit.tail = 0;
2821         info->first_recv_buffer = info->last_recv_buffer = NULL;
2822         info->recv_cnt = info->max_recv_cnt = 0;
2823
2824         for (i = 0; i < SERIAL_RECV_DESCRIPTORS; i++)
2825                 info->rec_descr[i].buf = 0;
2826
2827         /*
2828          * and set the speed and other flags of the serial port
2829          * this will start the rx/tx as well
2830          */
2831 #ifdef SERIAL_HANDLE_EARLY_ERRORS
2832         e100_enable_serial_data_irq(info);
2833 #endif
2834         change_speed(info);
2835
2836         /* dummy read to reset any serial errors */
2837
2838         (void)info->ioport[REG_DATA];
2839
2840         /* enable the interrupts */
2841         if (info->uses_dma_out)
2842                 e100_enable_txdma_irq(info);
2843
2844         e100_enable_rx_irq(info);
2845
2846         info->tr_running = 0; /* to be sure we don't lock up the transmitter */
2847
2848         /* setup the dma input descriptor and start dma */
2849
2850         start_receive(info);
2851
2852         /* for safety, make sure the descriptors last result is 0 bytes written */
2853
2854         info->tr_descr.sw_len = 0;
2855         info->tr_descr.hw_len = 0;
2856         info->tr_descr.status = 0;
2857
2858         /* enable RTS/DTR last */
2859
2860         e100_rts(info, 1);
2861         e100_dtr(info, 1);
2862
2863 #endif /* CONFIG_SVINTO_SIM */
2864
2865         info->flags |= ASYNC_INITIALIZED;
2866
2867         local_irq_restore(flags);
2868         return 0;
2869 }
2870
2871 /*
2872  * This routine will shutdown a serial port; interrupts are disabled, and
2873  * DTR is dropped if the hangup on close termio flag is on.
2874  */
2875 static void
2876 shutdown(struct e100_serial * info)
2877 {
2878         unsigned long flags;
2879         struct etrax_dma_descr *descr = info->rec_descr;
2880         struct etrax_recv_buffer *buffer;
2881         int i;
2882
2883 #ifndef CONFIG_SVINTO_SIM
2884         /* shut down the transmitter and receiver */
2885         DFLOW(DEBUG_LOG(info->line, "shutdown %i\n", info->line));
2886         e100_disable_rx(info);
2887         info->ioport[REG_TR_CTRL] = (info->tx_ctrl &= ~0x40);
2888
2889         /* disable interrupts, reset dma channels */
2890         if (info->uses_dma_in) {
2891                 e100_disable_rxdma_irq(info);
2892                 *info->icmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, reset);
2893                 info->uses_dma_in = 0;
2894         } else {
2895                 e100_disable_serial_data_irq(info);
2896         }
2897
2898         if (info->uses_dma_out) {
2899                 e100_disable_txdma_irq(info);
2900                 info->tr_running = 0;
2901                 *info->ocmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, reset);
2902                 info->uses_dma_out = 0;
2903         } else {
2904                 e100_disable_serial_tx_ready_irq(info);
2905                 info->tr_running = 0;
2906         }
2907
2908 #endif /* CONFIG_SVINTO_SIM */
2909
2910         if (!(info->flags & ASYNC_INITIALIZED))
2911                 return;
2912
2913 #ifdef SERIAL_DEBUG_OPEN
2914         printk("Shutting down serial port %d (irq %d)....\n", info->line,
2915                info->irq);
2916 #endif
2917
2918         local_irq_save(flags);
2919
2920         if (info->xmit.buf) {
2921                 free_page((unsigned long)info->xmit.buf);
2922                 info->xmit.buf = NULL;
2923         }
2924
2925         for (i = 0; i < SERIAL_RECV_DESCRIPTORS; i++)
2926                 if (descr[i].buf) {
2927                         buffer = phys_to_virt(descr[i].buf) - sizeof *buffer;
2928                         kfree(buffer);
2929                         descr[i].buf = 0;
2930                 }
2931
2932         if (!info->port.tty || (info->port.tty->termios->c_cflag & HUPCL)) {
2933                 /* hang up DTR and RTS if HUPCL is enabled */
2934                 e100_dtr(info, 0);
2935                 e100_rts(info, 0); /* could check CRTSCTS before doing this */
2936         }
2937
2938         if (info->port.tty)
2939                 set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2940
2941         info->flags &= ~ASYNC_INITIALIZED;
2942         local_irq_restore(flags);
2943 }
2944
2945
2946 /* change baud rate and other assorted parameters */
2947
2948 static void
2949 change_speed(struct e100_serial *info)
2950 {
2951         unsigned int cflag;
2952         unsigned long xoff;
2953         unsigned long flags;
2954         /* first some safety checks */
2955
2956         if (!info->port.tty || !info->port.tty->termios)
2957                 return;
2958         if (!info->ioport)
2959                 return;
2960
2961         cflag = info->port.tty->termios->c_cflag;
2962
2963         /* possibly, the tx/rx should be disabled first to do this safely */
2964
2965         /* change baud-rate and write it to the hardware */
2966         if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) {
2967                 /* Special baudrate */
2968                 u32 mask = 0xFF << (info->line*8); /* Each port has 8 bits */
2969                 unsigned long alt_source =
2970                                 IO_STATE(R_ALT_SER_BAUDRATE, ser0_rec, normal) |
2971                                 IO_STATE(R_ALT_SER_BAUDRATE, ser0_tr, normal);
2972                 /* R_ALT_SER_BAUDRATE selects the source */
2973                 DBAUD(printk("Custom baudrate: baud_base/divisor %lu/%i\n",
2974                        (unsigned long)info->baud_base, info->custom_divisor));
2975                 if (info->baud_base == SERIAL_PRESCALE_BASE) {
2976                         /* 0, 2-65535 (0=65536) */
2977                         u16 divisor = info->custom_divisor;
2978                         /* R_SERIAL_PRESCALE (upper 16 bits of R_CLOCK_PRESCALE) */
2979                         /* baudrate is 3.125MHz/custom_divisor */
2980                         alt_source =
2981                                 IO_STATE(R_ALT_SER_BAUDRATE, ser0_rec, prescale) |
2982                                 IO_STATE(R_ALT_SER_BAUDRATE, ser0_tr, prescale);
2983                         alt_source = 0x11;
2984                         DBAUD(printk("Writing SERIAL_PRESCALE: divisor %i\n", divisor));
2985                         *R_SERIAL_PRESCALE = divisor;
2986                         info->baud = SERIAL_PRESCALE_BASE/divisor;
2987                 }
2988 #ifdef CONFIG_ETRAX_EXTERN_PB6CLK_ENABLED
2989                 else if ((info->baud_base==CONFIG_ETRAX_EXTERN_PB6CLK_FREQ/8 &&
2990                           info->custom_divisor == 1) ||
2991                          (info->baud_base==CONFIG_ETRAX_EXTERN_PB6CLK_FREQ &&
2992                           info->custom_divisor == 8)) {
2993                                 /* ext_clk selected */
2994                                 alt_source =
2995                                         IO_STATE(R_ALT_SER_BAUDRATE, ser0_rec, extern) |
2996                                         IO_STATE(R_ALT_SER_BAUDRATE, ser0_tr, extern);
2997                                 DBAUD(printk("using external baudrate: %lu\n", CONFIG_ETRAX_EXTERN_PB6CLK_FREQ/8));
2998                                 info->baud = CONFIG_ETRAX_EXTERN_PB6CLK_FREQ/8;
2999                         }
3000 #endif
3001                 else
3002                 {
3003                         /* Bad baudbase, we don't support using timer0
3004                          * for baudrate.
3005                          */
3006                         printk(KERN_WARNING "Bad baud_base/custom_divisor: %lu/%i\n",
3007                                (unsigned long)info->baud_base, info->custom_divisor);
3008                 }
3009                 r_alt_ser_baudrate_shadow &= ~mask;
3010                 r_alt_ser_baudrate_shadow |= (alt_source << (info->line*8));
3011                 *R_ALT_SER_BAUDRATE = r_alt_ser_baudrate_shadow;
3012         } else {
3013                 /* Normal baudrate */
3014                 /* Make sure we use normal baudrate */
3015                 u32 mask = 0xFF << (info->line*8); /* Each port has 8 bits */
3016                 unsigned long alt_source =
3017                         IO_STATE(R_ALT_SER_BAUDRATE, ser0_rec, normal) |
3018                         IO_STATE(R_ALT_SER_BAUDRATE, ser0_tr, normal);
3019                 r_alt_ser_baudrate_shadow &= ~mask;
3020                 r_alt_ser_baudrate_shadow |= (alt_source << (info->line*8));
3021 #ifndef CONFIG_SVINTO_SIM
3022                 *R_ALT_SER_BAUDRATE = r_alt_ser_baudrate_shadow;
3023 #endif /* CONFIG_SVINTO_SIM */
3024
3025                 info->baud = cflag_to_baud(cflag);
3026 #ifndef CONFIG_SVINTO_SIM
3027                 info->ioport[REG_BAUD] = cflag_to_etrax_baud(cflag);
3028 #endif /* CONFIG_SVINTO_SIM */
3029         }
3030
3031 #ifndef CONFIG_SVINTO_SIM
3032         /* start with default settings and then fill in changes */
3033         local_irq_save(flags);
3034         /* 8 bit, no/even parity */
3035         info->rx_ctrl &= ~(IO_MASK(R_SERIAL0_REC_CTRL, rec_bitnr) |
3036                            IO_MASK(R_SERIAL0_REC_CTRL, rec_par_en) |
3037                            IO_MASK(R_SERIAL0_REC_CTRL, rec_par));
3038
3039         /* 8 bit, no/even parity, 1 stop bit, no cts */
3040         info->tx_ctrl &= ~(IO_MASK(R_SERIAL0_TR_CTRL, tr_bitnr) |
3041                            IO_MASK(R_SERIAL0_TR_CTRL, tr_par_en) |
3042                            IO_MASK(R_SERIAL0_TR_CTRL, tr_par) |
3043                            IO_MASK(R_SERIAL0_TR_CTRL, stop_bits) |
3044                            IO_MASK(R_SERIAL0_TR_CTRL, auto_cts));
3045
3046         if ((cflag & CSIZE) == CS7) {
3047                 /* set 7 bit mode */
3048                 info->tx_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_bitnr, tr_7bit);
3049                 info->rx_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_bitnr, rec_7bit);
3050         }
3051
3052         if (cflag & CSTOPB) {
3053                 /* set 2 stop bit mode */
3054                 info->tx_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, stop_bits, two_bits);
3055         }
3056
3057         if (cflag & PARENB) {
3058                 /* enable parity */
3059                 info->tx_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_par_en, enable);
3060                 info->rx_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_par_en, enable);
3061         }
3062
3063         if (cflag & CMSPAR) {
3064                 /* enable stick parity, PARODD mean Mark which matches ETRAX */
3065                 info->tx_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_stick_par, stick);
3066                 info->rx_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_stick_par, stick);
3067         }
3068         if (cflag & PARODD) {
3069                 /* set odd parity (or Mark if CMSPAR) */
3070                 info->tx_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_par, odd);
3071                 info->rx_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_par, odd);
3072         }
3073
3074         if (cflag & CRTSCTS) {
3075                 /* enable automatic CTS handling */
3076                 DFLOW(DEBUG_LOG(info->line, "FLOW auto_cts enabled\n", 0));
3077                 info->tx_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, auto_cts, active);
3078         }
3079
3080         /* make sure the tx and rx are enabled */
3081
3082         info->tx_ctrl |= IO_STATE(R_SERIAL0_TR_CTRL, tr_enable, enable);
3083         info->rx_ctrl |= IO_STATE(R_SERIAL0_REC_CTRL, rec_enable, enable);
3084
3085         /* actually write the control regs to the hardware */
3086
3087         info->ioport[REG_TR_CTRL] = info->tx_ctrl;
3088         info->ioport[REG_REC_CTRL] = info->rx_ctrl;
3089         xoff = IO_FIELD(R_SERIAL0_XOFF, xoff_char, STOP_CHAR(info->port.tty));
3090         xoff |= IO_STATE(R_SERIAL0_XOFF, tx_stop, enable);
3091         if (info->port.tty->termios->c_iflag & IXON ) {
3092                 DFLOW(DEBUG_LOG(info->line, "FLOW XOFF enabled 0x%02X\n",
3093                                 STOP_CHAR(info->port.tty)));
3094                 xoff |= IO_STATE(R_SERIAL0_XOFF, auto_xoff, enable);
3095         }
3096
3097         *((unsigned long *)&info->ioport[REG_XOFF]) = xoff;
3098         local_irq_restore(flags);
3099 #endif /* !CONFIG_SVINTO_SIM */
3100
3101         update_char_time(info);
3102
3103 } /* change_speed */
3104
3105 /* start transmitting chars NOW */
3106
3107 static void
3108 rs_flush_chars(struct tty_struct *tty)
3109 {
3110         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3111         unsigned long flags;
3112
3113         if (info->tr_running ||
3114             info->xmit.head == info->xmit.tail ||
3115             tty->stopped ||
3116             tty->hw_stopped ||
3117             !info->xmit.buf)
3118                 return;
3119
3120 #ifdef SERIAL_DEBUG_FLOW
3121         printk("rs_flush_chars\n");
3122 #endif
3123
3124         /* this protection might not exactly be necessary here */
3125
3126         local_irq_save(flags);
3127         start_transmit(info);
3128         local_irq_restore(flags);
3129 }
3130
3131 static int rs_raw_write(struct tty_struct *tty,
3132                         const unsigned char *buf, int count)
3133 {
3134         int     c, ret = 0;
3135         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3136         unsigned long flags;
3137
3138         /* first some sanity checks */
3139
3140         if (!tty || !info->xmit.buf)
3141                 return 0;
3142
3143 #ifdef SERIAL_DEBUG_DATA
3144         if (info->line == SERIAL_DEBUG_LINE)
3145                 printk("rs_raw_write (%d), status %d\n",
3146                        count, info->ioport[REG_STATUS]);
3147 #endif
3148
3149 #ifdef CONFIG_SVINTO_SIM
3150         /* Really simple.  The output is here and now. */
3151         SIMCOUT(buf, count);
3152         return count;
3153 #endif
3154         local_save_flags(flags);
3155         DFLOW(DEBUG_LOG(info->line, "write count %i ", count));
3156         DFLOW(DEBUG_LOG(info->line, "ldisc %i\n", tty->ldisc.chars_in_buffer(tty)));
3157
3158
3159         /* The local_irq_disable/restore_flags pairs below are needed
3160          * because the DMA interrupt handler moves the info->xmit values.
3161          * the memcpy needs to be in the critical region unfortunately,
3162          * because we need to read xmit values, memcpy, write xmit values
3163          * in one atomic operation... this could perhaps be avoided by
3164          * more clever design.
3165          */
3166         local_irq_disable();
3167                 while (count) {
3168                         c = CIRC_SPACE_TO_END(info->xmit.head,
3169                                               info->xmit.tail,
3170                                               SERIAL_XMIT_SIZE);
3171
3172                         if (count < c)
3173                                 c = count;
3174                         if (c <= 0)
3175                                 break;
3176
3177                         memcpy(info->xmit.buf + info->xmit.head, buf, c);
3178                         info->xmit.head = (info->xmit.head + c) &
3179                                 (SERIAL_XMIT_SIZE-1);
3180                         buf += c;
3181                         count -= c;
3182                         ret += c;
3183                 }
3184         local_irq_restore(flags);
3185
3186         /* enable transmitter if not running, unless the tty is stopped
3187          * this does not need IRQ protection since if tr_running == 0
3188          * the IRQ's are not running anyway for this port.
3189          */
3190         DFLOW(DEBUG_LOG(info->line, "write ret %i\n", ret));
3191
3192         if (info->xmit.head != info->xmit.tail &&
3193             !tty->stopped &&
3194             !tty->hw_stopped &&
3195             !info->tr_running) {
3196                 start_transmit(info);
3197         }
3198
3199         return ret;
3200 } /* raw_raw_write() */
3201
3202 static int
3203 rs_write(struct tty_struct *tty,
3204          const unsigned char *buf, int count)
3205 {
3206 #if defined(CONFIG_ETRAX_RS485)
3207         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3208
3209         if (info->rs485.flags & SER_RS485_ENABLED)
3210         {
3211                 /* If we are in RS-485 mode, we need to toggle RTS and disable
3212                  * the receiver before initiating a DMA transfer
3213                  */
3214 #ifdef CONFIG_ETRAX_FAST_TIMER
3215                 /* Abort any started timer */
3216                 fast_timers_rs485[info->line].function = NULL;
3217                 del_fast_timer(&fast_timers_rs485[info->line]);
3218 #endif
3219                 e100_rts(info, (info->rs485.flags & SER_RS485_RTS_ON_SEND));
3220 #if defined(CONFIG_ETRAX_RS485_DISABLE_RECEIVER)
3221                 e100_disable_rx(info);
3222                 e100_enable_rx_irq(info);
3223 #endif
3224                 if (info->rs485.delay_rts_before_send > 0)
3225                         msleep(info->rs485.delay_rts_before_send);
3226         }
3227 #endif /* CONFIG_ETRAX_RS485 */
3228
3229         count = rs_raw_write(tty, buf, count);
3230
3231 #if defined(CONFIG_ETRAX_RS485)
3232         if (info->rs485.flags & SER_RS485_ENABLED)
3233         {
3234                 unsigned int val;
3235                 /* If we are in RS-485 mode the following has to be done:
3236                  * wait until DMA is ready
3237                  * wait on transmit shift register
3238                  * toggle RTS
3239                  * enable the receiver
3240                  */
3241
3242                 /* Sleep until all sent */
3243                 tty_wait_until_sent(tty, 0);
3244 #ifdef CONFIG_ETRAX_FAST_TIMER
3245                 /* Now sleep a little more so that shift register is empty */
3246                 schedule_usleep(info->char_time_usec * 2);
3247 #endif
3248                 /* wait on transmit shift register */
3249                 do{
3250                         get_lsr_info(info, &val);
3251                 }while (!(val & TIOCSER_TEMT));
3252
3253                 e100_rts(info, (info->rs485.flags & SER_RS485_RTS_AFTER_SEND));
3254
3255 #if defined(CONFIG_ETRAX_RS485_DISABLE_RECEIVER)
3256                 e100_enable_rx(info);
3257                 e100_enable_rxdma_irq(info);
3258 #endif
3259         }
3260 #endif /* CONFIG_ETRAX_RS485 */
3261
3262         return count;
3263 } /* rs_write */
3264
3265
3266 /* how much space is available in the xmit buffer? */
3267
3268 static int
3269 rs_write_room(struct tty_struct *tty)
3270 {
3271         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3272
3273         return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
3274 }
3275
3276 /* How many chars are in the xmit buffer?
3277  * This does not include any chars in the transmitter FIFO.
3278  * Use wait_until_sent for waiting for FIFO drain.
3279  */
3280
3281 static int
3282 rs_chars_in_buffer(struct tty_struct *tty)
3283 {
3284         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3285
3286         return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
3287 }
3288
3289 /* discard everything in the xmit buffer */
3290
3291 static void
3292 rs_flush_buffer(struct tty_struct *tty)
3293 {
3294         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3295         unsigned long flags;
3296
3297         local_irq_save(flags);
3298         info->xmit.head = info->xmit.tail = 0;
3299         local_irq_restore(flags);
3300
3301         tty_wakeup(tty);
3302 }
3303
3304 /*
3305  * This function is used to send a high-priority XON/XOFF character to
3306  * the device
3307  *
3308  * Since we use DMA we don't check for info->x_char in transmit_chars_dma(),
3309  * but we do it in handle_ser_tx_interrupt().
3310  * We disable DMA channel and enable tx ready interrupt and write the
3311  * character when possible.
3312  */
3313 static void rs_send_xchar(struct tty_struct *tty, char ch)
3314 {
3315         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3316         unsigned long flags;
3317         local_irq_save(flags);
3318         if (info->uses_dma_out) {
3319                 /* Put the DMA on hold and disable the channel */
3320                 *info->ocmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, hold);
3321                 while (IO_EXTRACT(R_DMA_CH6_CMD, cmd, *info->ocmdadr) !=
3322                        IO_STATE_VALUE(R_DMA_CH6_CMD, cmd, hold));
3323                 e100_disable_txdma_channel(info);
3324         }
3325
3326         /* Must make sure transmitter is not stopped before we can transmit */
3327         if (tty->stopped)
3328                 rs_start(tty);
3329
3330         /* Enable manual transmit interrupt and send from there */
3331         DFLOW(DEBUG_LOG(info->line, "rs_send_xchar 0x%02X\n", ch));
3332         info->x_char = ch;
3333         e100_enable_serial_tx_ready_irq(info);
3334         local_irq_restore(flags);
3335 }
3336
3337 /*
3338  * ------------------------------------------------------------
3339  * rs_throttle()
3340  *
3341  * This routine is called by the upper-layer tty layer to signal that
3342  * incoming characters should be throttled.
3343  * ------------------------------------------------------------
3344  */
3345 static void
3346 rs_throttle(struct tty_struct * tty)
3347 {
3348         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3349 #ifdef SERIAL_DEBUG_THROTTLE
3350         char    buf[64];
3351
3352         printk("throttle %s: %lu....\n", tty_name(tty, buf),
3353                (unsigned long)tty->ldisc.chars_in_buffer(tty));
3354 #endif
3355         DFLOW(DEBUG_LOG(info->line,"rs_throttle %lu\n", tty->ldisc.chars_in_buffer(tty)));
3356
3357         /* Do RTS before XOFF since XOFF might take some time */
3358         if (tty->termios->c_cflag & CRTSCTS) {
3359                 /* Turn off RTS line */
3360                 e100_rts(info, 0);
3361         }
3362         if (I_IXOFF(tty))
3363                 rs_send_xchar(tty, STOP_CHAR(tty));
3364
3365 }
3366
3367 static void
3368 rs_unthrottle(struct tty_struct * tty)
3369 {
3370         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3371 #ifdef SERIAL_DEBUG_THROTTLE
3372         char    buf[64];
3373
3374         printk("unthrottle %s: %lu....\n", tty_name(tty, buf),
3375                (unsigned long)tty->ldisc.chars_in_buffer(tty));
3376 #endif
3377         DFLOW(DEBUG_LOG(info->line,"rs_unthrottle ldisc %d\n", tty->ldisc.chars_in_buffer(tty)));
3378         DFLOW(DEBUG_LOG(info->line,"rs_unthrottle flip.count: %i\n", tty->flip.count));
3379         /* Do RTS before XOFF since XOFF might take some time */
3380         if (tty->termios->c_cflag & CRTSCTS) {
3381                 /* Assert RTS line  */
3382                 e100_rts(info, 1);
3383         }
3384
3385         if (I_IXOFF(tty)) {
3386                 if (info->x_char)
3387                         info->x_char = 0;
3388                 else
3389                         rs_send_xchar(tty, START_CHAR(tty));
3390         }
3391
3392 }
3393
3394 /*
3395  * ------------------------------------------------------------
3396  * rs_ioctl() and friends
3397  * ------------------------------------------------------------
3398  */
3399
3400 static int
3401 get_serial_info(struct e100_serial * info,
3402                 struct serial_struct * retinfo)
3403 {
3404         struct serial_struct tmp;
3405
3406         /* this is all probably wrong, there are a lot of fields
3407          * here that we don't have in e100_serial and maybe we
3408          * should set them to something else than 0.
3409          */
3410
3411         if (!retinfo)
3412                 return -EFAULT;
3413         memset(&tmp, 0, sizeof(tmp));
3414         tmp.type = info->type;
3415         tmp.line = info->line;
3416         tmp.port = (int)info->ioport;
3417         tmp.irq = info->irq;
3418         tmp.flags = info->flags;
3419         tmp.baud_base = info->baud_base;
3420         tmp.close_delay = info->close_delay;
3421         tmp.closing_wait = info->closing_wait;
3422         tmp.custom_divisor = info->custom_divisor;
3423         if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
3424                 return -EFAULT;
3425         return 0;
3426 }
3427
3428 static int
3429 set_serial_info(struct e100_serial *info,
3430                 struct serial_struct *new_info)
3431 {
3432         struct serial_struct new_serial;
3433         struct e100_serial old_info;
3434         int retval = 0;
3435
3436         if (copy_from_user(&new_serial, new_info, sizeof(new_serial)))
3437                 return -EFAULT;
3438
3439         old_info = *info;
3440
3441         if (!capable(CAP_SYS_ADMIN)) {
3442                 if ((new_serial.type != info->type) ||
3443                     (new_serial.close_delay != info->close_delay) ||
3444                     ((new_serial.flags & ~ASYNC_USR_MASK) !=
3445                      (info->flags & ~ASYNC_USR_MASK)))
3446                         return -EPERM;
3447                 info->flags = ((info->flags & ~ASYNC_USR_MASK) |
3448                                (new_serial.flags & ASYNC_USR_MASK));
3449                 goto check_and_exit;
3450         }
3451
3452         if (info->count > 1)
3453                 return -EBUSY;
3454
3455         /*
3456          * OK, past this point, all the error checking has been done.
3457          * At this point, we start making changes.....
3458          */
3459
3460         info->baud_base = new_serial.baud_base;
3461         info->flags = ((info->flags & ~ASYNC_FLAGS) |
3462                        (new_serial.flags & ASYNC_FLAGS));
3463         info->custom_divisor = new_serial.custom_divisor;
3464         info->type = new_serial.type;
3465         info->close_delay = new_serial.close_delay;
3466         info->closing_wait = new_serial.closing_wait;
3467         info->port.tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
3468
3469  check_and_exit:
3470         if (info->flags & ASYNC_INITIALIZED) {
3471                 change_speed(info);
3472         } else
3473                 retval = startup(info);
3474         return retval;
3475 }
3476
3477 /*
3478  * get_lsr_info - get line status register info
3479  *
3480  * Purpose: Let user call ioctl() to get info when the UART physically
3481  *          is emptied.  On bus types like RS485, the transmitter must
3482  *          release the bus after transmitting. This must be done when
3483  *          the transmit shift register is empty, not be done when the
3484  *          transmit holding register is empty.  This functionality
3485  *          allows an RS485 driver to be written in user space.
3486  */
3487 static int
3488 get_lsr_info(struct e100_serial * info, unsigned int *value)
3489 {
3490         unsigned int result = TIOCSER_TEMT;
3491 #ifndef CONFIG_SVINTO_SIM
3492         unsigned long curr_time = jiffies;
3493         unsigned long curr_time_usec = GET_JIFFIES_USEC();
3494         unsigned long elapsed_usec =
3495                 (curr_time - info->last_tx_active) * 1000000/HZ +
3496                 curr_time_usec - info->last_tx_active_usec;
3497
3498         if (info->xmit.head != info->xmit.tail ||
3499             elapsed_usec < 2*info->char_time_usec) {
3500                 result = 0;
3501         }
3502 #endif
3503
3504         if (copy_to_user(value, &result, sizeof(int)))
3505                 return -EFAULT;
3506         return 0;
3507 }
3508
3509 #ifdef SERIAL_DEBUG_IO
3510 struct state_str
3511 {
3512         int state;
3513         const char *str;
3514 };
3515
3516 const struct state_str control_state_str[] = {
3517         {TIOCM_DTR, "DTR" },
3518         {TIOCM_RTS, "RTS"},
3519         {TIOCM_ST, "ST?" },
3520         {TIOCM_SR, "SR?" },
3521         {TIOCM_CTS, "CTS" },
3522         {TIOCM_CD, "CD" },
3523         {TIOCM_RI, "RI" },
3524         {TIOCM_DSR, "DSR" },
3525         {0, NULL }
3526 };
3527
3528 char *get_control_state_str(int MLines, char *s)
3529 {
3530         int i = 0;
3531
3532         s[0]='\0';
3533         while (control_state_str[i].str != NULL) {
3534                 if (MLines & control_state_str[i].state) {
3535                         if (s[0] != '\0') {
3536                                 strcat(s, ", ");
3537                         }
3538                         strcat(s, control_state_str[i].str);
3539                 }
3540                 i++;
3541         }
3542         return s;
3543 }
3544 #endif
3545
3546 static int
3547 rs_break(struct tty_struct *tty, int break_state)
3548 {
3549         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3550         unsigned long flags;
3551
3552         if (!info->ioport)
3553                 return -EIO;
3554
3555         local_irq_save(flags);
3556         if (break_state == -1) {
3557                 /* Go to manual mode and set the txd pin to 0 */
3558                 /* Clear bit 7 (txd) and 6 (tr_enable) */
3559                 info->tx_ctrl &= 0x3F;
3560         } else {
3561                 /* Set bit 7 (txd) and 6 (tr_enable) */
3562                 info->tx_ctrl |= (0x80 | 0x40);
3563         }
3564         info->ioport[REG_TR_CTRL] = info->tx_ctrl;
3565         local_irq_restore(flags);
3566         return 0;
3567 }
3568
3569 static int
3570 rs_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear)
3571 {
3572         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3573         unsigned long flags;
3574
3575         local_irq_save(flags);
3576
3577         if (clear & TIOCM_RTS)
3578                 e100_rts(info, 0);
3579         if (clear & TIOCM_DTR)
3580                 e100_dtr(info, 0);
3581         /* Handle FEMALE behaviour */
3582         if (clear & TIOCM_RI)
3583                 e100_ri_out(info, 0);
3584         if (clear & TIOCM_CD)
3585                 e100_cd_out(info, 0);
3586
3587         if (set & TIOCM_RTS)
3588                 e100_rts(info, 1);
3589         if (set & TIOCM_DTR)
3590                 e100_dtr(info, 1);
3591         /* Handle FEMALE behaviour */
3592         if (set & TIOCM_RI)
3593                 e100_ri_out(info, 1);
3594         if (set & TIOCM_CD)
3595                 e100_cd_out(info, 1);
3596
3597         local_irq_restore(flags);
3598         return 0;
3599 }
3600
3601 static int
3602 rs_tiocmget(struct tty_struct *tty)
3603 {
3604         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3605         unsigned int result;
3606         unsigned long flags;
3607
3608         local_irq_save(flags);
3609
3610         result =
3611                 (!E100_RTS_GET(info) ? TIOCM_RTS : 0)
3612                 | (!E100_DTR_GET(info) ? TIOCM_DTR : 0)
3613                 | (!E100_RI_GET(info) ? TIOCM_RNG : 0)
3614                 | (!E100_DSR_GET(info) ? TIOCM_DSR : 0)
3615                 | (!E100_CD_GET(info) ? TIOCM_CAR : 0)
3616                 | (!E100_CTS_GET(info) ? TIOCM_CTS : 0);
3617
3618         local_irq_restore(flags);
3619
3620 #ifdef SERIAL_DEBUG_IO
3621         printk(KERN_DEBUG "ser%i: modem state: %i 0x%08X\n",
3622                 info->line, result, result);
3623         {
3624                 char s[100];
3625
3626                 get_control_state_str(result, s);
3627                 printk(KERN_DEBUG "state: %s\n", s);
3628         }
3629 #endif
3630         return result;
3631
3632 }
3633
3634
3635 static int
3636 rs_ioctl(struct tty_struct *tty,
3637          unsigned int cmd, unsigned long arg)
3638 {
3639         struct e100_serial * info = (struct e100_serial *)tty->driver_data;
3640
3641         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
3642             (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
3643             (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
3644                 if (tty->flags & (1 << TTY_IO_ERROR))
3645                         return -EIO;
3646         }
3647
3648         switch (cmd) {
3649         case TIOCGSERIAL:
3650                 return get_serial_info(info,
3651                                        (struct serial_struct *) arg);
3652         case TIOCSSERIAL:
3653                 return set_serial_info(info,
3654                                        (struct serial_struct *) arg);
3655         case TIOCSERGETLSR: /* Get line status register */
3656                 return get_lsr_info(info, (unsigned int *) arg);
3657
3658         case TIOCSERGSTRUCT:
3659                 if (copy_to_user((struct e100_serial *) arg,
3660                                  info, sizeof(struct e100_serial)))
3661                         return -EFAULT;
3662                 return 0;
3663
3664 #if defined(CONFIG_ETRAX_RS485)
3665         case TIOCSERSETRS485:
3666         {
3667                 /* In this ioctl we still use the old structure
3668                  * rs485_control for backward compatibility
3669                  * (if we use serial_rs485, then old user-level code
3670                  * wouldn't work anymore...).
3671                  * The use of this ioctl is deprecated: use TIOCSRS485
3672                  * instead.*/
3673                 struct rs485_control rs485ctrl;
3674                 struct serial_rs485 rs485data;
3675                 printk(KERN_DEBUG "The use of this ioctl is deprecated. Use TIOCSRS485 instead\n");
3676                 if (copy_from_user(&rs485ctrl, (struct rs485_control *)arg,
3677                                 sizeof(rs485ctrl)))
3678                         return -EFAULT;
3679
3680                 rs485data.delay_rts_before_send = rs485ctrl.delay_rts_before_send;
3681                 rs485data.flags = 0;
3682
3683                 if (rs485ctrl.enabled)
3684                         rs485data.flags |= SER_RS485_ENABLED;
3685                 else
3686                         rs485data.flags &= ~(SER_RS485_ENABLED);
3687
3688                 if (rs485ctrl.rts_on_send)
3689                         rs485data.flags |= SER_RS485_RTS_ON_SEND;
3690                 else
3691                         rs485data.flags &= ~(SER_RS485_RTS_ON_SEND);
3692
3693                 if (rs485ctrl.rts_after_sent)
3694                         rs485data.flags |= SER_RS485_RTS_AFTER_SEND;
3695                 else
3696                         rs485data.flags &= ~(SER_RS485_RTS_AFTER_SEND);
3697
3698                 return e100_enable_rs485(tty, &rs485data);
3699         }
3700
3701         case TIOCSRS485:
3702         {
3703                 /* This is the new version of TIOCSRS485, with new
3704                  * data structure serial_rs485 */
3705                 struct serial_rs485 rs485data;
3706                 if (copy_from_user(&rs485data, (struct rs485_control *)arg,
3707                                 sizeof(rs485data)))
3708                         return -EFAULT;
3709
3710                 return e100_enable_rs485(tty, &rs485data);
3711         }
3712
3713         case TIOCGRS485:
3714         {
3715                 struct serial_rs485 *rs485data =
3716                         &(((struct e100_serial *)tty->driver_data)->rs485);
3717                 /* This is the ioctl to get RS485 data from user-space */
3718                 if (copy_to_user((struct serial_rs485 *) arg,
3719                                         rs485data,
3720                                         sizeof(struct serial_rs485)))
3721                         return -EFAULT;
3722                 break;
3723         }
3724
3725         case TIOCSERWRRS485:
3726         {
3727                 struct rs485_write rs485wr;
3728                 if (copy_from_user(&rs485wr, (struct rs485_write *)arg,
3729                                 sizeof(rs485wr)))
3730                         return -EFAULT;
3731
3732                 return e100_write_rs485(tty, rs485wr.outc, rs485wr.outc_size);
3733         }
3734 #endif
3735
3736         default:
3737                 return -ENOIOCTLCMD;
3738         }
3739         return 0;
3740 }
3741
3742 static void
3743 rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
3744 {
3745         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3746
3747         change_speed(info);
3748
3749         /* Handle turning off CRTSCTS */
3750         if ((old_termios->c_cflag & CRTSCTS) &&
3751             !(tty->termios->c_cflag & CRTSCTS)) {
3752                 tty->hw_stopped = 0;
3753                 rs_start(tty);
3754         }
3755
3756 }
3757
3758 /*
3759  * ------------------------------------------------------------
3760  * rs_close()
3761  *
3762  * This routine is called when the serial port gets closed.  First, we
3763  * wait for the last remaining data to be sent.  Then, we unlink its
3764  * S structure from the interrupt chain if necessary, and we free
3765  * that IRQ if nothing is left in the chain.
3766  * ------------------------------------------------------------
3767  */
3768 static void
3769 rs_close(struct tty_struct *tty, struct file * filp)
3770 {
3771         struct e100_serial * info = (struct e100_serial *)tty->driver_data;
3772         unsigned long flags;
3773
3774         if (!info)
3775                 return;
3776
3777         /* interrupts are disabled for this entire function */
3778
3779         local_irq_save(flags);
3780
3781         if (tty_hung_up_p(filp)) {
3782                 local_irq_restore(flags);
3783                 return;
3784         }
3785
3786 #ifdef SERIAL_DEBUG_OPEN
3787         printk("[%d] rs_close ttyS%d, count = %d\n", current->pid,
3788                info->line, info->count);
3789 #endif
3790         if ((tty->count == 1) && (info->count != 1)) {
3791                 /*
3792                  * Uh, oh.  tty->count is 1, which means that the tty
3793                  * structure will be freed.  Info->count should always
3794                  * be one in these conditions.  If it's greater than
3795                  * one, we've got real problems, since it means the
3796                  * serial port won't be shutdown.
3797                  */
3798                 printk(KERN_ERR
3799                        "rs_close: bad serial port count; tty->count is 1, "
3800                        "info->count is %d\n", info->count);
3801                 info->count = 1;
3802         }
3803         if (--info->count < 0) {
3804                 printk(KERN_ERR "rs_close: bad serial port count for ttyS%d: %d\n",
3805                        info->line, info->count);
3806                 info->count = 0;
3807         }
3808         if (info->count) {
3809                 local_irq_restore(flags);
3810                 return;
3811         }
3812         info->flags |= ASYNC_CLOSING;
3813         /*
3814          * Save the termios structure, since this port may have
3815          * separate termios for callout and dialin.
3816          */
3817         if (info->flags & ASYNC_NORMAL_ACTIVE)
3818                 info->normal_termios = *tty->termios;
3819         /*
3820          * Now we wait for the transmit buffer to clear; and we notify
3821          * the line discipline to only process XON/XOFF characters.
3822          */
3823         tty->closing = 1;
3824         if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
3825                 tty_wait_until_sent(tty, info->closing_wait);
3826         /*
3827          * At this point we stop accepting input.  To do this, we
3828          * disable the serial receiver and the DMA receive interrupt.
3829          */
3830 #ifdef SERIAL_HANDLE_EARLY_ERRORS
3831         e100_disable_serial_data_irq(info);
3832 #endif
3833
3834 #ifndef CONFIG_SVINTO_SIM
3835         e100_disable_rx(info);
3836         e100_disable_rx_irq(info);
3837
3838         if (info->flags & ASYNC_INITIALIZED) {
3839                 /*
3840                  * Before we drop DTR, make sure the UART transmitter
3841                  * has completely drained; this is especially
3842                  * important as we have a transmit FIFO!
3843                  */
3844                 rs_wait_until_sent(tty, HZ);
3845         }
3846 #endif
3847
3848         shutdown(info);
3849         rs_flush_buffer(tty);
3850         tty_ldisc_flush(tty);
3851         tty->closing = 0;
3852         info->event = 0;
3853         info->port.tty = NULL;
3854         if (info->blocked_open) {
3855                 if (info->close_delay)
3856                         schedule_timeout_interruptible(info->close_delay);
3857                 wake_up_interruptible(&info->open_wait);
3858         }
3859         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
3860         wake_up_interruptible(&info->close_wait);
3861         local_irq_restore(flags);
3862
3863         /* port closed */
3864
3865 #if defined(CONFIG_ETRAX_RS485)
3866         if (info->rs485.flags & SER_RS485_ENABLED) {
3867                 info->rs485.flags &= ~(SER_RS485_ENABLED);
3868 #if defined(CONFIG_ETRAX_RS485_ON_PA)
3869                 *R_PORT_PA_DATA = port_pa_data_shadow &= ~(1 << rs485_pa_bit);
3870 #endif
3871 #if defined(CONFIG_ETRAX_RS485_ON_PORT_G)
3872                 REG_SHADOW_SET(R_PORT_G_DATA, port_g_data_shadow,
3873                                rs485_port_g_bit, 0);
3874 #endif
3875 #if defined(CONFIG_ETRAX_RS485_LTC1387)
3876                 REG_SHADOW_SET(R_PORT_G_DATA, port_g_data_shadow,
3877                                CONFIG_ETRAX_RS485_LTC1387_DXEN_PORT_G_BIT, 0);
3878                 REG_SHADOW_SET(R_PORT_G_DATA, port_g_data_shadow,
3879                                CONFIG_ETRAX_RS485_LTC1387_RXEN_PORT_G_BIT, 0);
3880 #endif
3881         }
3882 #endif
3883
3884         /*
3885          * Release any allocated DMA irq's.
3886          */
3887         if (info->dma_in_enabled) {
3888                 free_irq(info->dma_in_irq_nbr, info);
3889                 cris_free_dma(info->dma_in_nbr, info->dma_in_irq_description);
3890                 info->uses_dma_in = 0;
3891 #ifdef SERIAL_DEBUG_OPEN
3892                 printk(KERN_DEBUG "DMA irq '%s' freed\n",
3893                         info->dma_in_irq_description);
3894 #endif
3895         }
3896         if (info->dma_out_enabled) {
3897                 free_irq(info->dma_out_irq_nbr, info);
3898                 cris_free_dma(info->dma_out_nbr, info->dma_out_irq_description);
3899                 info->uses_dma_out = 0;
3900 #ifdef SERIAL_DEBUG_OPEN
3901                 printk(KERN_DEBUG "DMA irq '%s' freed\n",
3902                         info->dma_out_irq_description);
3903 #endif
3904         }
3905 }
3906
3907 /*
3908  * rs_wait_until_sent() --- wait until the transmitter is empty
3909  */
3910 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
3911 {
3912         unsigned long orig_jiffies;
3913         struct e100_serial *info = (struct e100_serial *)tty->driver_data;
3914         unsigned long curr_time = jiffies;
3915         unsigned long curr_time_usec = GET_JIFFIES_USEC();
3916         long elapsed_usec =
3917                 (curr_time - info->last_tx_active) * (1000000/HZ) +
3918                 curr_time_usec - info->last_tx_active_usec;
3919
3920         /*
3921          * Check R_DMA_CHx_STATUS bit 0-6=number of available bytes in FIFO
3922          * R_DMA_CHx_HWSW bit 31-16=nbr of bytes left in DMA buffer (0=64k)
3923          */
3924         orig_jiffies = jiffies;
3925         while (info->xmit.head != info->xmit.tail || /* More in send queue */
3926                (*info->ostatusadr & 0x007f) ||  /* more in FIFO */
3927                (elapsed_usec < 2*info->char_time_usec)) {
3928                 schedule_timeout_interruptible(1);
3929                 if (signal_pending(current))
3930                         break;
3931                 if (timeout && time_after(jiffies, orig_jiffies + timeout))
3932                         break;
3933                 curr_time = jiffies;
3934                 curr_time_usec = GET_JIFFIES_USEC();
3935                 elapsed_usec =
3936                         (curr_time - info->last_tx_active) * (1000000/HZ) +
3937                         curr_time_usec - info->last_tx_active_usec;
3938         }
3939         set_current_state(TASK_RUNNING);
3940 }
3941
3942 /*
3943  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
3944  */
3945 void
3946 rs_hangup(struct tty_struct *tty)
3947 {
3948         struct e100_serial * info = (struct e100_serial *)tty->driver_data;
3949
3950         rs_flush_buffer(tty);
3951         shutdown(info);
3952         info->event = 0;
3953         info->count = 0;
3954         info->flags &= ~ASYNC_NORMAL_ACTIVE;
3955         info->port.tty = NULL;
3956         wake_up_interruptible(&info->open_wait);
3957 }
3958
3959 /*
3960  * ------------------------------------------------------------
3961  * rs_open() and friends
3962  * ------------------------------------------------------------
3963  */
3964 static int
3965 block_til_ready(struct tty_struct *tty, struct file * filp,
3966                 struct e100_serial *info)
3967 {
3968         DECLARE_WAITQUEUE(wait, current);
3969         unsigned long   flags;
3970         int             retval;
3971         int             do_clocal = 0, extra_count = 0;
3972
3973         /*
3974          * If the device is in the middle of being closed, then block
3975          * until it's done, and then try again.
3976          */
3977         if (tty_hung_up_p(filp) ||
3978             (info->flags & ASYNC_CLOSING)) {
3979                 wait_event_interruptible_tty(tty, info->close_wait,
3980                         !(info->flags & ASYNC_CLOSING));
3981 #ifdef SERIAL_DO_RESTART
3982                 if (info->flags & ASYNC_HUP_NOTIFY)
3983                         return -EAGAIN;
3984                 else
3985                         return -ERESTARTSYS;
3986 #else
3987                 return -EAGAIN;
3988 #endif
3989         }
3990
3991         /*
3992          * If non-blocking mode is set, or the port is not enabled,
3993          * then make the check up front and then exit.
3994          */
3995         if ((filp->f_flags & O_NONBLOCK) ||
3996             (tty->flags & (1 << TTY_IO_ERROR))) {
3997                 info->flags |= ASYNC_NORMAL_ACTIVE;
3998                 return 0;
3999         }
4000
4001         if (tty->termios->c_cflag & CLOCAL) {
4002                         do_clocal = 1;
4003         }
4004
4005         /*
4006          * Block waiting for the carrier detect and the line to become
4007          * free (i.e., not in use by the callout).  While we are in
4008          * this loop, info->count is dropped by one, so that
4009          * rs_close() knows when to free things.  We restore it upon
4010          * exit, either normal or abnormal.
4011          */
4012         retval = 0;
4013         add_wait_queue(&info->open_wait, &wait);
4014 #ifdef SERIAL_DEBUG_OPEN
4015         printk("block_til_ready before block: ttyS%d, count = %d\n",
4016                info->line, info->count);
4017 #endif
4018         local_irq_save(flags);
4019         if (!tty_hung_up_p(filp)) {
4020                 extra_count++;
4021                 info->count--;
4022         }
4023         local_irq_restore(flags);
4024         info->blocked_open++;
4025         while (1) {
4026                 local_irq_save(flags);
4027                 /* assert RTS and DTR */
4028                 e100_rts(info, 1);
4029                 e100_dtr(info, 1);
4030                 local_irq_restore(flags);
4031                 set_current_state(TASK_INTERRUPTIBLE);
4032                 if (tty_hung_up_p(filp) ||
4033                     !(info->flags & ASYNC_INITIALIZED)) {
4034 #ifdef SERIAL_DO_RESTART
4035                         if (info->flags & ASYNC_HUP_NOTIFY)
4036                                 retval = -EAGAIN;
4037                         else
4038                                 retval = -ERESTARTSYS;
4039 #else
4040                         retval = -EAGAIN;
4041 #endif
4042                         break;
4043                 }
4044                 if (!(info->flags & ASYNC_CLOSING) && do_clocal)
4045                         /* && (do_clocal || DCD_IS_ASSERTED) */
4046                         break;
4047                 if (signal_pending(current)) {
4048                         retval = -ERESTARTSYS;
4049                         break;
4050                 }
4051 #ifdef SERIAL_DEBUG_OPEN
4052                 printk("block_til_ready blocking: ttyS%d, count = %d\n",
4053                        info->line, info->count);
4054 #endif
4055                 tty_unlock(tty);
4056                 schedule();
4057                 tty_lock(tty);
4058         }
4059         set_current_state(TASK_RUNNING);
4060         remove_wait_queue(&info->open_wait, &wait);
4061         if (extra_count)
4062                 info->count++;
4063         info->blocked_open--;
4064 #ifdef SERIAL_DEBUG_OPEN
4065         printk("block_til_ready after blocking: ttyS%d, count = %d\n",
4066                info->line, info->count);
4067 #endif
4068         if (retval)
4069                 return retval;
4070         info->flags |= ASYNC_NORMAL_ACTIVE;
4071         return 0;
4072 }
4073
4074 static void
4075 deinit_port(struct e100_serial *info)
4076 {
4077         if (info->dma_out_enabled) {
4078                 cris_free_dma(info->dma_out_nbr, info->dma_out_irq_description);
4079                 free_irq(info->dma_out_irq_nbr, info);
4080         }
4081         if (info->dma_in_enabled) {
4082                 cris_free_dma(info->dma_in_nbr, info->dma_in_irq_description);
4083                 free_irq(info->dma_in_irq_nbr, info);
4084         }
4085 }
4086
4087 /*
4088  * This routine is called whenever a serial port is opened.
4089  * It performs the serial-specific initialization for the tty structure.
4090  */
4091 static int
4092 rs_open(struct tty_struct *tty, struct file * filp)
4093 {
4094         struct e100_serial      *info;
4095         int                     retval;
4096         int                     allocated_resources = 0;
4097
4098         info = rs_table + tty->index;
4099         if (!info->enabled)
4100                 return -ENODEV;
4101
4102 #ifdef SERIAL_DEBUG_OPEN
4103         printk("[%d] rs_open %s, count = %d\n", current->pid, tty->name,
4104                info->count);
4105 #endif
4106
4107         info->count++;
4108         tty->driver_data = info;
4109         info->port.tty = tty;
4110
4111         tty->low_latency = !!(info->flags & ASYNC_LOW_LATENCY);
4112
4113         /*
4114          * If the port is in the middle of closing, bail out now
4115          */
4116         if (tty_hung_up_p(filp) ||
4117             (info->flags & ASYNC_CLOSING)) {
4118                 wait_event_interruptible_tty(tty, info->close_wait,
4119                         !(info->flags & ASYNC_CLOSING));
4120 #ifdef SERIAL_DO_RESTART
4121                 return ((info->flags & ASYNC_HUP_NOTIFY) ?
4122                         -EAGAIN : -ERESTARTSYS);
4123 #else
4124                 return -EAGAIN;
4125 #endif
4126         }
4127
4128         /*
4129          * If DMA is enabled try to allocate the irq's.
4130          */
4131         if (info->count == 1) {
4132                 allocated_resources = 1;
4133                 if (info->dma_in_enabled) {
4134                         if (request_irq(info->dma_in_irq_nbr,
4135                                         rec_interrupt,
4136                                         info->dma_in_irq_flags,
4137                                         info->dma_in_irq_description,
4138                                         info)) {
4139                                 printk(KERN_WARNING "DMA irq '%s' busy; "
4140                                         "falling back to non-DMA mode\n",
4141                                         info->dma_in_irq_description);
4142                                 /* Make sure we never try to use DMA in */
4143                                 /* for the port again. */
4144                                 info->dma_in_enabled = 0;
4145                         } else if (cris_request_dma(info->dma_in_nbr,
4146                                         info->dma_in_irq_description,
4147                                         DMA_VERBOSE_ON_ERROR,
4148                                         info->dma_owner)) {
4149                                 free_irq(info->dma_in_irq_nbr, info);
4150                                 printk(KERN_WARNING "DMA '%s' busy; "
4151                                         "falling back to non-DMA mode\n",
4152                                         info->dma_in_irq_description);
4153                                 /* Make sure we never try to use DMA in */
4154                                 /* for the port again. */
4155                                 info->dma_in_enabled = 0;
4156                         }
4157 #ifdef SERIAL_DEBUG_OPEN
4158                         else
4159                                 printk(KERN_DEBUG "DMA irq '%s' allocated\n",
4160                                         info->dma_in_irq_description);
4161 #endif
4162                 }
4163                 if (info->dma_out_enabled) {
4164                         if (request_irq(info->dma_out_irq_nbr,
4165                                                tr_interrupt,
4166                                                info->dma_out_irq_flags,
4167                                                info->dma_out_irq_description,
4168                                                info)) {
4169                                 printk(KERN_WARNING "DMA irq '%s' busy; "
4170                                         "falling back to non-DMA mode\n",
4171                                         info->dma_out_irq_description);
4172                                 /* Make sure we never try to use DMA out */
4173                                 /* for the port again. */
4174                                 info->dma_out_enabled = 0;
4175                         } else if (cris_request_dma(info->dma_out_nbr,
4176                                              info->dma_out_irq_description,
4177                                              DMA_VERBOSE_ON_ERROR,
4178                                              info->dma_owner)) {
4179                                 free_irq(info->dma_out_irq_nbr, info);
4180                                 printk(KERN_WARNING "DMA '%s' busy; "
4181                                         "falling back to non-DMA mode\n",
4182                                         info->dma_out_irq_description);
4183                                 /* Make sure we never try to use DMA out */
4184                                 /* for the port again. */
4185                                 info->dma_out_enabled = 0;
4186                         }
4187 #ifdef SERIAL_DEBUG_OPEN
4188                         else
4189                                 printk(KERN_DEBUG "DMA irq '%s' allocated\n",
4190                                         info->dma_out_irq_description);
4191 #endif
4192                 }
4193         }
4194
4195         /*
4196          * Start up the serial port
4197          */
4198
4199         retval = startup(info);
4200         if (retval) {
4201                 if (allocated_resources)
4202                         deinit_port(info);
4203
4204                 /* FIXME Decrease count info->count here too? */
4205                 return retval;
4206         }
4207
4208
4209         retval = block_til_ready(tty, filp, info);
4210         if (retval) {
4211 #ifdef SERIAL_DEBUG_OPEN
4212                 printk("rs_open returning after block_til_ready with %d\n",
4213                        retval);
4214 #endif
4215                 if (allocated_resources)
4216                         deinit_port(info);
4217
4218                 return retval;
4219         }
4220
4221         if ((info->count == 1) && (info->flags & ASYNC_SPLIT_TERMIOS)) {
4222                 *tty->termios = info->normal_termios;
4223                 change_speed(info);
4224         }
4225
4226 #ifdef SERIAL_DEBUG_OPEN
4227         printk("rs_open ttyS%d successful...\n", info->line);
4228 #endif
4229         DLOG_INT_TRIG( log_int_pos = 0);
4230
4231         DFLIP(  if (info->line == SERIAL_DEBUG_LINE) {
4232                         info->icount.rx = 0;
4233                 } );
4234
4235         return 0;
4236 }
4237
4238 #ifdef CONFIG_PROC_FS
4239 /*
4240  * /proc fs routines....
4241  */
4242
4243 static void seq_line_info(struct seq_file *m, struct e100_serial *info)
4244 {
4245         unsigned long tmp;
4246
4247         seq_printf(m, "%d: uart:E100 port:%lX irq:%d",
4248                    info->line, (unsigned long)info->ioport, info->irq);
4249
4250         if (!info->ioport || (info->type == PORT_UNKNOWN)) {
4251                 seq_printf(m, "\n");
4252                 return;
4253         }
4254
4255         seq_printf(m, " baud:%d", info->baud);
4256         seq_printf(m, " tx:%lu rx:%lu",
4257                        (unsigned long)info->icount.tx,
4258                        (unsigned long)info->icount.rx);
4259         tmp = CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
4260         if (tmp)
4261                 seq_printf(m, " tx_pend:%lu/%lu",
4262                            (unsigned long)tmp,
4263                            (unsigned long)SERIAL_XMIT_SIZE);
4264
4265         seq_printf(m, " rx_pend:%lu/%lu",
4266                    (unsigned long)info->recv_cnt,
4267                    (unsigned long)info->max_recv_cnt);
4268
4269 #if 1
4270         if (info->port.tty) {
4271                 if (info->port.tty->stopped)
4272                         seq_printf(m, " stopped:%i",
4273                                    (int)info->port.tty->stopped);
4274                 if (info->port.tty->hw_stopped)
4275                         seq_printf(m, " hw_stopped:%i",
4276                                    (int)info->port.tty->hw_stopped);
4277         }
4278
4279         {
4280                 unsigned char rstat = info->ioport[REG_STATUS];
4281                 if (rstat & IO_MASK(R_SERIAL0_STATUS, xoff_detect))
4282                         seq_printf(m, " xoff_detect:1");
4283         }
4284
4285 #endif
4286
4287         if (info->icount.frame)
4288                 seq_printf(m, " fe:%lu", (unsigned long)info->icount.frame);
4289
4290         if (info->icount.parity)
4291                 seq_printf(m, " pe:%lu", (unsigned long)info->icount.parity);
4292
4293         if (info->icount.brk)
4294                 seq_printf(m, " brk:%lu", (unsigned long)info->icount.brk);
4295
4296         if (info->icount.overrun)
4297                 seq_printf(m, " oe:%lu", (unsigned long)info->icount.overrun);
4298
4299         /*
4300          * Last thing is the RS-232 status lines
4301          */
4302         if (!E100_RTS_GET(info))
4303                 seq_puts(m, "|RTS");
4304         if (!E100_CTS_GET(info))
4305                 seq_puts(m, "|CTS");
4306         if (!E100_DTR_GET(info))
4307                 seq_puts(m, "|DTR");
4308         if (!E100_DSR_GET(info))
4309                 seq_puts(m, "|DSR");
4310         if (!E100_CD_GET(info))
4311                 seq_puts(m, "|CD");
4312         if (!E100_RI_GET(info))
4313                 seq_puts(m, "|RI");
4314         seq_puts(m, "\n");
4315 }
4316
4317
4318 static int crisv10_proc_show(struct seq_file *m, void *v)
4319 {
4320         int i;
4321
4322         seq_printf(m, "serinfo:1.0 driver:%s\n", serial_version);
4323
4324         for (i = 0; i < NR_PORTS; i++) {
4325                 if (!rs_table[i].enabled)
4326                         continue;
4327                 seq_line_info(m, &rs_table[i]);
4328         }
4329 #ifdef DEBUG_LOG_INCLUDED
4330         for (i = 0; i < debug_log_pos; i++) {
4331                 seq_printf(m, "%-4i %lu.%lu ",
4332                          i, debug_log[i].time,
4333                          timer_data_to_ns(debug_log[i].timer_data));
4334                 seq_printf(m, debug_log[i].string, debug_log[i].value);
4335         }
4336         seq_printf(m, "debug_log %i/%i\n", i, DEBUG_LOG_SIZE);
4337         debug_log_pos = 0;
4338 #endif
4339         return 0;
4340 }
4341
4342 static int crisv10_proc_open(struct inode *inode, struct file *file)
4343 {
4344         return single_open(file, crisv10_proc_show, NULL);
4345 }
4346
4347 static const struct file_operations crisv10_proc_fops = {
4348         .owner          = THIS_MODULE,
4349         .open           = crisv10_proc_open,
4350         .read           = seq_read,
4351         .llseek         = seq_lseek,
4352         .release        = single_release,
4353 };
4354 #endif
4355
4356
4357 /* Finally, routines used to initialize the serial driver. */
4358
4359 static void show_serial_version(void)
4360 {
4361         printk(KERN_INFO
4362                "ETRAX 100LX serial-driver %s, "
4363                "(c) 2000-2004 Axis Communications AB\r\n",
4364                &serial_version[11]); /* "$Revision: x.yy" */
4365 }
4366
4367 /* rs_init inits the driver at boot (using the module_init chain) */
4368
4369 static const struct tty_operations rs_ops = {
4370         .open = rs_open,
4371         .close = rs_close,
4372         .write = rs_write,
4373         .flush_chars = rs_flush_chars,
4374         .write_room = rs_write_room,
4375         .chars_in_buffer = rs_chars_in_buffer,
4376         .flush_buffer = rs_flush_buffer,
4377         .ioctl = rs_ioctl,
4378         .throttle = rs_throttle,
4379         .unthrottle = rs_unthrottle,
4380         .set_termios = rs_set_termios,
4381         .stop = rs_stop,
4382         .start = rs_start,
4383         .hangup = rs_hangup,
4384         .break_ctl = rs_break,
4385         .send_xchar = rs_send_xchar,
4386         .wait_until_sent = rs_wait_until_sent,
4387         .tiocmget = rs_tiocmget,
4388         .tiocmset = rs_tiocmset,
4389 #ifdef CONFIG_PROC_FS
4390         .proc_fops = &crisv10_proc_fops,
4391 #endif
4392 };
4393
4394 static int __init rs_init(void)
4395 {
4396         int i;
4397         struct e100_serial *info;
4398         struct tty_driver *driver = alloc_tty_driver(NR_PORTS);
4399
4400         if (!driver)
4401                 return -ENOMEM;
4402
4403         show_serial_version();
4404
4405         /* Setup the timed flush handler system */
4406
4407 #if !defined(CONFIG_ETRAX_SERIAL_FAST_TIMER)
4408         setup_timer(&flush_timer, timed_flush_handler, 0);
4409         mod_timer(&flush_timer, jiffies + 5);
4410 #endif
4411
4412 #if defined(CONFIG_ETRAX_RS485)
4413 #if defined(CONFIG_ETRAX_RS485_ON_PA)
4414         if (cris_io_interface_allocate_pins(if_serial_0, 'a', rs485_pa_bit,
4415                         rs485_pa_bit)) {
4416                 printk(KERN_ERR "ETRAX100LX serial: Could not allocate "
4417                         "RS485 pin\n");
4418                 put_tty_driver(driver);
4419                 return -EBUSY;
4420         }
4421 #endif
4422 #if defined(CONFIG_ETRAX_RS485_ON_PORT_G)
4423         if (cris_io_interface_allocate_pins(if_serial_0, 'g', rs485_pa_bit,
4424                         rs485_port_g_bit)) {
4425                 printk(KERN_ERR "ETRAX100LX serial: Could not allocate "
4426                         "RS485 pin\n");
4427                 put_tty_driver(driver);
4428                 return -EBUSY;
4429         }
4430 #endif
4431 #endif
4432
4433         /* Initialize the tty_driver structure */
4434
4435         driver->driver_name = "serial";
4436         driver->name = "ttyS";
4437         driver->major = TTY_MAJOR;
4438         driver->minor_start = 64;
4439         driver->type = TTY_DRIVER_TYPE_SERIAL;
4440         driver->subtype = SERIAL_TYPE_NORMAL;
4441         driver->init_termios = tty_std_termios;
4442         driver->init_termios.c_cflag =
4443                 B115200 | CS8 | CREAD | HUPCL | CLOCAL; /* is normally B9600 default... */
4444         driver->init_termios.c_ispeed = 115200;
4445         driver->init_termios.c_ospeed = 115200;
4446         driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
4447
4448         tty_set_operations(driver, &rs_ops);
4449         serial_driver = driver;
4450         if (tty_register_driver(driver))
4451                 panic("Couldn't register serial driver\n");
4452         /* do some initializing for the separate ports */
4453
4454         for (i = 0, info = rs_table; i < NR_PORTS; i++,info++) {
4455                 if (info->enabled) {
4456                         if (cris_request_io_interface(info->io_if,
4457                                         info->io_if_description)) {
4458                                 printk(KERN_ERR "ETRAX100LX async serial: "
4459                                         "Could not allocate IO pins for "
4460                                         "%s, port %d\n",
4461                                         info->io_if_description, i);
4462                                 info->enabled = 0;
4463                         }
4464                 }
4465                 tty_port_init(&info->port);
4466                 info->uses_dma_in = 0;
4467                 info->uses_dma_out = 0;
4468                 info->line = i;
4469                 info->port.tty = NULL;
4470                 info->type = PORT_ETRAX;
4471                 info->tr_running = 0;
4472                 info->forced_eop = 0;
4473                 info->baud_base = DEF_BAUD_BASE;
4474                 info->custom_divisor = 0;
4475                 info->flags = 0;
4476                 info->close_delay = 5*HZ/10;
4477                 info->closing_wait = 30*HZ;
4478                 info->x_char = 0;
4479                 info->event = 0;
4480                 info->count = 0;
4481                 info->blocked_open = 0;
4482                 info->normal_termios = driver->init_termios;
4483                 init_waitqueue_head(&info->open_wait);
4484                 init_waitqueue_head(&info->close_wait);
4485                 info->xmit.buf = NULL;
4486                 info->xmit.tail = info->xmit.head = 0;
4487                 info->first_recv_buffer = info->last_recv_buffer = NULL;
4488                 info->recv_cnt = info->max_recv_cnt = 0;
4489                 info->last_tx_active_usec = 0;
4490                 info->last_tx_active = 0;
4491
4492 #if defined(CONFIG_ETRAX_RS485)
4493                 /* Set sane defaults */
4494                 info->rs485.flags &= ~(SER_RS485_RTS_ON_SEND);
4495                 info->rs485.flags |= SER_RS485_RTS_AFTER_SEND;
4496                 info->rs485.delay_rts_before_send = 0;
4497                 info->rs485.flags &= ~(SER_RS485_ENABLED);
4498 #endif
4499                 INIT_WORK(&info->work, do_softint);
4500
4501                 if (info->enabled) {
4502                         printk(KERN_INFO "%s%d at %p is a builtin UART with DMA\n",
4503                                serial_driver->name, info->line, info->ioport);
4504                 }
4505         }
4506 #ifdef CONFIG_ETRAX_FAST_TIMER
4507 #ifdef CONFIG_ETRAX_SERIAL_FAST_TIMER
4508         memset(fast_timers, 0, sizeof(fast_timers));
4509 #endif
4510 #ifdef CONFIG_ETRAX_RS485
4511         memset(fast_timers_rs485, 0, sizeof(fast_timers_rs485));
4512 #endif
4513         fast_timer_init();
4514 #endif
4515
4516 #ifndef CONFIG_SVINTO_SIM
4517 #ifndef CONFIG_ETRAX_KGDB
4518         /* Not needed in simulator.  May only complicate stuff. */
4519         /* hook the irq's for DMA channel 6 and 7, serial output and input, and some more... */
4520
4521         if (request_irq(SERIAL_IRQ_NBR, ser_interrupt,
4522                         IRQF_SHARED, "serial ", driver))
4523                 panic("%s: Failed to request irq8", __func__);
4524
4525 #endif
4526 #endif /* CONFIG_SVINTO_SIM */
4527
4528         return 0;
4529 }
4530
4531 /* this makes sure that rs_init is called during kernel boot */
4532
4533 module_init(rs_init);