drivers/input/touchscreen/xpt2046_ts.c

   1 /*
   2  * drivers/input/touchscreen/xpt2046_ts.c - driver for rk2818 spi xpt2046 device and console
   3  *
   4  * Copyright (C) 2010 ROCKCHIP, Inc.
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/hwmon.h>
  17 #include <linux/init.h>
  18 #include <linux/err.h>
  19 #include <linux/delay.h>
  20 #include <linux/input.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/slab.h>
  23 #include <linux/gpio.h>
  24 #include <linux/spi/spi.h>
  25 #include <asm/irq.h>
  26
  27 #include "xpt2046_ts.h"
  28
  29 /*
  30  * This code has been heavily tested on a Nokia 770, and lightly
  31  * tested on other xpt2046 devices (OSK/Mistral, Lubbock).
  32  * TSC2046 is just newer xpt2046 silicon.
  33  * Support for ads7843 tested on Atmel at91sam926x-EK.
  34  * Support for ads7845 has only been stubbed in.
  35  *
  36  * IRQ handling needs a workaround because of a shortcoming in handling
  37  * edge triggered IRQs on some platforms like the OMAP1/2. These
  38  * platforms don't handle the ARM lazy IRQ disabling properly, thus we
  39  * have to maintain our own SW IRQ disabled status. This should be
  40  * removed as soon as the affected platform's IRQ handling is fixed.
  41  *
  42  * app note sbaa036 talks in more detail about accurate sampling...
  43  * that ought to help in situations like LCDs inducing noise (which
  44  * can also be helped by using synch signals) and more generally.
  45  * This driver tries to utilize the measures described in the app
  46  * note. The strength of filtering can be set in the board-* specific
  47  * files.
  48  */
  49 #define XPT2046_DEBUG                   0
  50 #if XPT2046_DEBUG
  51         #define xpt2046printk(msg...)   printk(msg);
  52 #else
  53         #define xpt2046printk(msg...)
  54 #endif
  55 #define LCD_MAX_LENGTH                          800
  56 #define LCD_MAX_WIDTH                           480
  57 #define PT2046_TOUCH_AD_LEFT            3855
  58 #define PT2046_TOUCH_AD_RIGHT           260
  59 #define PT2046_TOUCH_AD_TOP             300
  60 #define PT2046_TOUCH_AD_BOTTOM  3755
  61 #define AD_TO_X(adx)    (LCD_MAX_WIDTH * (adx - PT2046_TOUCH_AD_TOP) / ( PT2046_TOUCH_AD_BOTTOM  - PT2046_TOUCH_AD_TOP ))
  62 #define AD_TO_Y(ady)    (LCD_MAX_LENGTH * (PT2046_TOUCH_AD_LEFT - ady) / (PT2046_TOUCH_AD_LEFT - PT2046_TOUCH_AD_RIGHT))
  63
  64 #define TS_POLL_DELAY   (15 * 1000000)  /* ns delay before the first sample */
  65 #define TS_POLL_PERIOD  (15 * 1000000)  /* ns delay between samples */
  66
  67 #define DEBOUNCE_REPTIME  3
  68 /* this driver doesn't aim at the peak continuous sample rate */
  69 #define SAMPLE_BITS     (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */)
  70
  71 struct ts_event {
  72         /* For portability, we can't read 12 bit values using SPI (which
  73          * would make the controller deliver them as native byteorder u16
  74          * with msbs zeroed).  Instead, we read them as two 8-bit values,
  75          * *** WHICH NEED BYTESWAPPING *** and range adjustment.
  76          */
  77         u16     x;
  78         u16     y;
  79         int     ignore;
  80 };
  81
  82 /*
  83  * We allocate this separately to avoid cache line sharing issues when
  84  * driver is used with DMA-based SPI controllers (like atmel_spi) on
  85  * systems where main memory is not DMA-coherent (most non-x86 boards).
  86  */
  87 struct xpt2046_packet {
  88         u8                      read_x, read_y, pwrdown;
  89         u16                     dummy;          /* for the pwrdown read */
  90         struct ts_event         tc;
  91 };
  92
  93 struct xpt2046 {
  94         struct input_dev        *input;
  95         char                    phys[32];
  96         char                    name[32];
  97
  98         struct spi_device       *spi;
  99
 100         u16                     model;
 101         bool                    swap_xy;
 102
 103         struct xpt2046_packet   *packet;
 104
 105         struct spi_transfer     xfer[18];
 106         struct spi_message      msg[5];
 107         struct spi_message      *last_msg;
 108         int                     msg_idx;
 109         int                     read_cnt;
 110         int                     read_rep;
 111         int                     last_read;
 112
 113         u16                     debounce_max;
 114         u16                     debounce_tol;
 115         u16                     debounce_rep;
 116
 117         u16                     penirq_recheck_delay_usecs;
 118
 119         spinlock_t              lock;
 120         struct hrtimer          timer;
 121         unsigned                pendown:1;      /* P: lock */
 122         unsigned                pending:1;      /* P: lock */
 123 // FIXME remove "irq_disabled"
 124         unsigned                irq_disabled:1; /* P: lock */
 125         unsigned                disabled:1;
 126         unsigned                is_suspended:1;
 127
 128         int                     (*filter)(void *data, int data_idx, int *val);
 129         void                    *filter_data;
 130         void                    (*filter_cleanup)(void *data);
 131         int                     (*get_pendown_state)(void);
 132         int                     gpio_pendown;
 133
 134         void                    (*wait_for_sync)(void);
 135 };
 136
 137 /* leave chip selected when we're done, for quicker re-select? */
 138 #if     0
 139 #define CS_CHANGE(xfer) ((xfer).cs_change = 1)
 140 #else
 141 #define CS_CHANGE(xfer) ((xfer).cs_change = 0)
 142 #endif
 143
 144 /*--------------------------------------------------------------------------*/
 145
 146 /* The xpt2046 has touchscreen and other sensors.
 147  * Earlier xpt2046 chips are somewhat compatible.
 148  */
 149 #define XPT2046_START                   (1 << 7)
 150 #define XPT2046_A2A1A0_d_y              (1 << 4)        /* differential */
 151 #define XPT2046_A2A1A0_d_z1             (3 << 4)        /* differential */
 152 #define XPT2046_A2A1A0_d_z2             (4 << 4)        /* differential */
 153 #define XPT2046_A2A1A0_d_x              (5 << 4)        /* differential */
 154 #define XPT2046_A2A1A0_temp0    (0 << 4)        /* non-differential */
 155 #define XPT2046_A2A1A0_vbatt    (2 << 4)        /* non-differential */
 156 #define XPT2046_A2A1A0_vaux             (6 << 4)        /* non-differential */
 157 #define XPT2046_A2A1A0_temp1    (7 << 4)        /* non-differential */
 158 #define XPT2046_8_BIT                   (1 << 3)
 159 #define XPT2046_12_BIT                  (0 << 3)
 160 #define XPT2046_SER                             (1 << 2)        /* non-differential */
 161 #define XPT2046_DFR                             (0 << 2)        /* differential */
 162 #define XPT2046_PD10_PDOWN              (0 << 0)        /* lowpower mode + penirq */
 163 #define XPT2046_PD10_ADC_ON             (1 << 0)        /* ADC on */
 164 #define XPT2046_PD10_REF_ON             (2 << 0)        /* vREF on + penirq */
 165 #define XPT2046_PD10_ALL_ON             (3 << 0)        /* ADC + vREF on */
 166
 167 #define MAX_12BIT       ((1<<12)-1)
 168
 169 /* leave ADC powered up (disables penirq) between differential samples */
 170 #define READ_12BIT_DFR(x, adc, vref) (XPT2046_START | XPT2046_A2A1A0_d_ ## x \
 171         | XPT2046_12_BIT | XPT2046_DFR | \
 172         (adc ? XPT2046_PD10_ADC_ON : 0) | (vref ? XPT2046_PD10_REF_ON : 0))
 173
 174 #define READ_Y(vref)    (READ_12BIT_DFR(y,  1, vref))
 175 #define READ_Z1(vref)   (READ_12BIT_DFR(z1, 1, vref))
 176 #define READ_Z2(vref)   (READ_12BIT_DFR(z2, 1, vref))
 177
 178 #define READ_X(vref)    (READ_12BIT_DFR(x,  1, vref))
 179 #define PWRDOWN         (READ_12BIT_DFR(y,  0, 0))      /* LAST */
 180
 181 /* single-ended samples need to first power up reference voltage;
 182  * we leave both ADC and VREF powered
 183  */
 184 #define READ_12BIT_SER(x) (XPT2046_START | XPT2046_A2A1A0_ ## x \
 185         | XPT2046_12_BIT | XPT2046_SER)
 186
 187 #define REF_ON  (READ_12BIT_DFR(x, 1, 1))
 188 #define REF_OFF (READ_12BIT_DFR(y, 0, 0))
 189
 190 /*--------------------------------------------------------------------------*/
 191 /*
 192  * touchscreen sensors  use differential conversions.
 193  */
 194
 195 struct dfr_req {
 196         u8                      command;
 197         u8                      pwrdown;
 198         u16                     dummy;          /* for the pwrdown read */
 199         __be16                  sample;
 200         struct spi_message      msg;
 201         struct spi_transfer     xfer[4];
 202 };
 203
 204 static struct xpt2046_platform_data xpt2046_info = {
 205         .model                  = 2046,
 206         .keep_vref_on   = 1,
 207         .swap_xy                = 1,
 208         .x_min                  = 0,
 209         .x_max                  = 800,
 210         .y_min                  = 0,
 211         .y_max                  = 480,
 212         .debounce_max           = 7,
 213         .debounce_rep           = DEBOUNCE_REPTIME,
 214         .debounce_tol           = 20,
 215         .gpio_pendown           = RK2818_PIN_PE3,
 216
 217 };
 218 static void xpt2046_enable(struct xpt2046 *ts);
 219 static void xpt2046_disable(struct xpt2046 *ts);
 220
 221 static int device_suspended(struct device *dev)
 222 {
 223         struct xpt2046 *ts = dev_get_drvdata(dev);
 224         return ts->is_suspended || ts->disabled;
 225 }
 226
 227 static int xpt2046_read12_dfr(struct device *dev, unsigned command)
 228 {
 229         struct spi_device       *spi = to_spi_device(dev);
 230         struct xpt2046          *ts = dev_get_drvdata(dev);
 231         struct dfr_req          *req = kzalloc(sizeof *req, GFP_KERNEL);
 232         int                     status;
 233
 234         if (!req)
 235                 return -ENOMEM;
 236
 237         spi_message_init(&req->msg);
 238
 239         /* take sample */
 240         req->command = (u8) command;
 241         req->xfer[0].tx_buf = &req->command;
 242         req->xfer[0].len = 1;
 243         spi_message_add_tail(&req->xfer[0], &req->msg);
 244
 245         req->xfer[1].rx_buf = &req->sample;
 246         req->xfer[1].len = 2;
 247         spi_message_add_tail(&req->xfer[1], &req->msg);
 248
 249         /* converter in low power mode & enable PENIRQ */
 250         req->pwrdown= PWRDOWN;
 251         req->xfer[2].tx_buf = &req->pwrdown;
 252         req->xfer[2].len = 1;
 253         spi_message_add_tail(&req->xfer[2], &req->msg);
 254
 255         req->xfer[3].rx_buf = &req->dummy;
 256         req->xfer[3].len = 2;
 257         CS_CHANGE(req->xfer[3]);
 258         spi_message_add_tail(&req->xfer[3], &req->msg);
 259
 260         ts->irq_disabled = 1;
 261         disable_irq(spi->irq);
 262         status = spi_sync(spi, &req->msg);
 263         ts->irq_disabled = 0;
 264         enable_irq(spi->irq);
 265
 266         if (status == 0) {
 267                 /* on-wire is a must-ignore bit, a BE12 value, then padding */
 268                 status = be16_to_cpu(req->sample);
 269                 status = status >> 3;
 270                 status &= 0x0fff;
 271                 xpt2046printk("***>%s:status=%d\n",__FUNCTION__,status);
 272         }
 273
 274         kfree(req);
 275         return status;
 276 }
 277
 278
 279
 280 /*--------------------------------------------------------------------------*/
 281
 282 static int get_pendown_state(struct xpt2046 *ts)
 283 {
 284         if (ts->get_pendown_state)
 285                 return ts->get_pendown_state();
 286
 287         return !gpio_get_value(ts->gpio_pendown);
 288 }
 289
 290 static void null_wait_for_sync(void)
 291 {
 292
 293 }
 294
 295 /*
 296  * PENIRQ only kicks the timer.  The timer only reissues the SPI transfer,
 297  * to retrieve touchscreen status.
 298  *
 299  * The SPI transfer completion callback does the real work.  It reports
 300  * touchscreen events and reactivates the timer (or IRQ) as appropriate.
 301  */
 302
 303 static void xpt2046_rx(void *xpt)
 304 {
 305         struct xpt2046          *ts = xpt;
 306         struct xpt2046_packet   *packet = ts->packet;
 307         unsigned                Rt = 1;
 308         u16                     x, y;
 309
 310         /* xpt2046_rx_val() did in-place conversion (including byteswap) from
 311          * on-the-wire format as part of debouncing to get stable readings.
 312          */
 313         x = packet->tc.x;
 314         y = packet->tc.y;
 315
 316         xpt2046printk("***>%s:x=%d,y=%d\n",__FUNCTION__,x,y);
 317
 318         /* range filtering */
 319         if (x == MAX_12BIT)
 320                 x = 0;
 321
 322         /* Sample found inconsistent by debouncing or pressure is beyond
 323          * the maximum. Don't report it to user space, repeat at least
 324          * once more the measurement
 325          */
 326         if (packet->tc.ignore) {
 327
 328                 xpt2046printk("***>%s:ignored=%d\n",__FUNCTION__,packet->tc.ignore);
 329
 330                 hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
 331                               HRTIMER_MODE_REL);
 332                 return;
 333         }
 334
 335         /* Maybe check the pendown state before reporting. This discards
 336          * false readings when the pen is lifted.
 337          */
 338         if (ts->penirq_recheck_delay_usecs) {
 339                 udelay(ts->penirq_recheck_delay_usecs);
 340                 if (!get_pendown_state(ts))
 341                 {
 342                         xpt2046printk("***>%s:get_pendown_state(ts)==0,discard false reading\n",__FUNCTION__);
 343                         Rt = 0;
 344                 }
 345         }
 346
 347         /* NOTE: We can't rely on the pressure to determine the pen down
 348          * state, even this controller has a pressure sensor.  The pressure
 349          * value can fluctuate for quite a while after lifting the pen and
 350          * in some cases may not even settle at the expected value.
 351          *
 352          * The only safe way to check for the pen up condition is in the
 353          * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
 354          */
 355         if (Rt) {
 356                 struct input_dev *input = ts->input;
 357                 if (!ts->pendown) {
 358                         input_report_key(input, BTN_TOUCH, 1);
 359                         ts->pendown = 1;
 360                         xpt2046printk("***>%s:input_report_key(pen down)\n",__FUNCTION__);
 361                 }
 362
 363                 x =  AD_TO_X(x);
 364                 y =  AD_TO_Y(y);
 365
 366                 if (ts->swap_xy)
 367                         swap(x, y);
 368
 369                 input_report_abs(input, ABS_X, x);
 370                 input_report_abs(input, ABS_Y, y);
 371
 372                 input_sync(input);
 373                 xpt2046printk("***>%s:input_report_abs(%4d/%4d)\n",__FUNCTION__,x, y);
 374         }
 375
 376         hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
 377                         HRTIMER_MODE_REL);
 378 }
 379
 380 static int xpt2046_debounce(void *xpt, int data_idx, int *val)
 381 {
 382         struct xpt2046          *ts = xpt;
 383         static int average_val[2];
 384
 385
 386         xpt2046printk("***>%s:%d,%d,%d,%d,%d,%d,%d,%d\n",__FUNCTION__,
 387                 data_idx,ts->last_read,
 388           ts->read_cnt,ts->debounce_max,
 389                 abs(ts->last_read - *val),ts->debounce_tol,
 390                 ts->read_rep,ts->debounce_rep);
 391
 392         /* discard the first sample. */
 393         if(!ts->read_cnt)
 394         {
 395                 udelay(100);
 396                 ts->read_cnt++;
 397                 return XPT2046_FILTER_REPEAT;
 398         }
 399
 400         if (ts->read_cnt==1 || (abs(ts->last_read - *val) > ts->debounce_tol)) {
 401                 /* Start over collecting consistent readings. */
 402                 ts->read_rep = 1;
 403                 average_val[data_idx] = *val;
 404                 /* Repeat it, if this was the first read or the read
 405                  * wasn't consistent enough. */
 406                 if (ts->read_cnt < ts->debounce_max) {
 407                         ts->last_read = *val;
 408                         ts->read_cnt++;
 409                         return XPT2046_FILTER_REPEAT;
 410                 } else {
 411                         /* Maximum number of debouncing reached and still
 412                          * not enough number of consistent readings. Abort
 413                          * the whole sample, repeat it in the next sampling
 414                          * period.
 415                          */
 416                         ts->read_cnt = 0;
 417                         ts->last_read = 0;
 418                         memset(average_val,0,sizeof(average_val));
 419                         xpt2046printk("***>%s:XPT2046_FILTER_IGNORE\n",__FUNCTION__);
 420                         return XPT2046_FILTER_IGNORE;
 421                 }
 422         }
 423         else {
 424                 average_val[data_idx] += *val;
 425
 426                 if (++ts->read_rep >= ts->debounce_rep) {
 427                         /* Got a good reading for this coordinate,
 428                          * go for the next one. */
 429                         ts->read_cnt = 0;
 430                         ts->read_rep = 0;
 431                         ts->last_read = 0;
 432                         *val = average_val[data_idx]/(ts->debounce_rep);
 433                         return XPT2046_FILTER_OK;
 434                 } else {
 435                         /* Read more values that are consistent. */
 436                         ts->read_cnt++;
 437
 438                         return XPT2046_FILTER_REPEAT;
 439                 }
 440         }
 441 }
 442
 443 static int xpt2046_no_filter(void *xpt, int data_idx, int *val)
 444 {
 445         return XPT2046_FILTER_OK;
 446 }
 447
 448 static void xpt2046_rx_val(void *xpt)
 449 {
 450         struct xpt2046 *ts = xpt;
 451         struct xpt2046_packet *packet = ts->packet;
 452         struct spi_message *m;
 453         struct spi_transfer *t;
 454         int val;
 455         int action;
 456         int status;
 457
 458         m = &ts->msg[ts->msg_idx];
 459         t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
 460
 461         /* adjust:  on-wire is a must-ignore bit, a BE12 value, then padding;
 462          * built from two 8 bit values written msb-first.
 463          */
 464         val = (be16_to_cpup((__be16 *)t->rx_buf) >> 3) & 0x0fff;
 465
 466         xpt2046printk("***>%s:value=%d\n",__FUNCTION__,val);
 467
 468         action = ts->filter(ts->filter_data, ts->msg_idx, &val);
 469         switch (action) {
 470         case XPT2046_FILTER_REPEAT:
 471                 break;
 472         case XPT2046_FILTER_IGNORE:
 473                 packet->tc.ignore = 1;
 474                 /* Last message will contain xpt2046_rx() as the
 475                  * completion function.
 476                  */
 477                 m = ts->last_msg;
 478                 break;
 479         case XPT2046_FILTER_OK:
 480                 *(u16 *)t->rx_buf = val;
 481                 packet->tc.ignore = 0;
 482                 m = &ts->msg[++ts->msg_idx];
 483                 break;
 484         default:
 485                 BUG();
 486         }
 487         ts->wait_for_sync();
 488         status = spi_async(ts->spi, m);
 489         if (status)
 490                 dev_err(&ts->spi->dev, "spi_async --> %d\n",
 491                                 status);
 492 }
 493
 494 static enum hrtimer_restart xpt2046_timer(struct hrtimer *handle)
 495 {
 496         struct xpt2046  *ts = container_of(handle, struct xpt2046, timer);
 497         int             status = 0;
 498
 499         spin_lock(&ts->lock);
 500
 501         if (unlikely(!get_pendown_state(ts) ||
 502                      device_suspended(&ts->spi->dev))) {
 503                 if (ts->pendown) {
 504                         struct input_dev *input = ts->input;
 505                         input_report_key(input, BTN_TOUCH, 0);
 506                         input_sync(input);
 507
 508                         ts->pendown = 0;
 509
 510                         xpt2046printk("***>%s:input_report_key(The touchscreen up)\n",__FUNCTION__);
 511                 }
 512
 513                 /* measurement cycle ended */
 514                 if (!device_suspended(&ts->spi->dev)) {
 515                         xpt2046printk("***>%s:device_suspended==0\n",__FUNCTION__);
 516                         ts->irq_disabled = 0;
 517                         enable_irq(ts->spi->irq);
 518                 }
 519                 ts->pending = 0;
 520         } else {
 521                 /* pen is still down, continue with the measurement */
 522                 xpt2046printk("***>%s:pen is still down, continue with the measurement\n",__FUNCTION__);
 523                 ts->msg_idx = 0;
 524                 ts->wait_for_sync();
 525                 status = spi_async(ts->spi, &ts->msg[0]);
 526                 if (status)
 527                         dev_err(&ts->spi->dev, "spi_async --> %d\n", status);
 528         }
 529
 530         spin_unlock(&ts->lock);
 531         return HRTIMER_NORESTART;
 532 }
 533
 534 static irqreturn_t xpt2046_irq(int irq, void *handle)
 535 {
 536         struct xpt2046 *ts = handle;
 537         unsigned long flags;
 538
 539         xpt2046printk("***>%s.....%s.....%d\n",__FILE__,__FUNCTION__,__LINE__);
 540
 541         spin_lock_irqsave(&ts->lock, flags);
 542
 543         if (likely(get_pendown_state(ts))) {
 544                 if (!ts->irq_disabled) {
 545                         /* The ARM do_simple_IRQ() dispatcher doesn't act
 546                          * like the other dispatchers:  it will report IRQs
 547                          * even after they've been disabled.  We work around
 548                          * that here.  (The "generic irq" framework may help...)
 549                          */
 550                         ts->irq_disabled = 1;
 551                         disable_irq_nosync(ts->spi->irq);
 552                         ts->pending = 1;
 553                         hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
 554                                         HRTIMER_MODE_REL);
 555                 }
 556         }
 557         spin_unlock_irqrestore(&ts->lock, flags);
 558
 559         return IRQ_HANDLED;
 560 }
 561
 562 /*--------------------------------------------------------------------------*/
 563
 564 /* Must be called with ts->lock held */
 565 static void xpt2046_disable(struct xpt2046 *ts)
 566 {
 567         if (ts->disabled)
 568                 return;
 569
 570         ts->disabled = 1;
 571
 572         /* are we waiting for IRQ, or polling? */
 573         if (!ts->pending) {
 574                 ts->irq_disabled = 1;
 575                 disable_irq(ts->spi->irq);
 576         } else {
 577                 /* the timer will run at least once more, and
 578                  * leave everything in a clean state, IRQ disabled
 579                  */
 580                 while (ts->pending) {
 581                         spin_unlock_irq(&ts->lock);
 582                         msleep(1);
 583                         spin_lock_irq(&ts->lock);
 584                 }
 585         }
 586
 587         /* we know the chip's in lowpower mode since we always
 588          * leave it that way after every request
 589          */
 590 }
 591
 592 /* Must be called with ts->lock held */
 593 static void xpt2046_enable(struct xpt2046 *ts)
 594 {
 595         if (!ts->disabled)
 596                 return;
 597
 598         ts->disabled = 0;
 599         ts->irq_disabled = 0;
 600         enable_irq(ts->spi->irq);
 601 }
 602
 603 static int xpt2046_suspend(struct spi_device *spi, pm_message_t message)
 604 {
 605         struct xpt2046 *ts = dev_get_drvdata(&spi->dev);
 606
 607         spin_lock_irq(&ts->lock);
 608
 609         ts->is_suspended = 1;
 610         xpt2046_disable(ts);
 611
 612         spin_unlock_irq(&ts->lock);
 613
 614         return 0;
 615
 616 }
 617
 618 static int xpt2046_resume(struct spi_device *spi)
 619 {
 620         struct xpt2046 *ts = dev_get_drvdata(&spi->dev);
 621
 622         spin_lock_irq(&ts->lock);
 623
 624         ts->is_suspended = 0;
 625         xpt2046_enable(ts);
 626
 627         spin_unlock_irq(&ts->lock);
 628
 629         return 0;
 630 }
 631
 632 static int __devinit setup_pendown(struct spi_device *spi, struct xpt2046 *ts)
 633 {
 634         struct xpt2046_platform_data *pdata = spi->dev.platform_data;
 635         int err;
 636
 637         /* REVISIT when the irq can be triggered active-low, or if for some
 638          * reason the touchscreen isn't hooked up, we don't need to access
 639          * the pendown state.
 640          */
 641         if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) {
 642                 dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
 643                 return -EINVAL;
 644         }
 645
 646         if (pdata->get_pendown_state) {
 647                 ts->get_pendown_state = pdata->get_pendown_state;
 648                 return 0;
 649         }
 650
 651         err = gpio_request(pdata->gpio_pendown, "xpt2046_pendown");
 652         if (err) {
 653                 dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
 654                                 pdata->gpio_pendown);
 655                 return err;
 656         }
 657
 658         ts->gpio_pendown = pdata->gpio_pendown;
 659         return 0;
 660 }
 661
 662 static int __devinit xpt2046_probe(struct spi_device *spi)
 663 {
 664         struct xpt2046                  *ts;
 665         struct xpt2046_packet           *packet;
 666         struct input_dev                *input_dev;
 667         struct xpt2046_platform_data    *pdata = spi->dev.platform_data;
 668         struct spi_message              *m;
 669         struct spi_transfer             *x;
 670         int                             vref;
 671         int                             err;
 672
 673
 674
 675         if (!spi->irq) {
 676                 dev_dbg(&spi->dev, "no IRQ?\n");
 677                 return -ENODEV;
 678         }
 679         else{
 680                 spi->irq = gpio_to_irq(spi->irq);
 681                 dev_dbg(&spi->dev, "no IRQ?\n");
 682         }
 683
 684         if (!pdata) {
 685                 spi->dev.platform_data = &xpt2046_info;
 686                 pdata = spi->dev.platform_data;
 687         }
 688
 689         /* don't exceed max specified sample rate */
 690         if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
 691                 dev_dbg(&spi->dev, "f(sample) %d KHz?\n",
 692                                 (spi->max_speed_hz/SAMPLE_BITS)/1000);
 693                 return -EINVAL;
 694         }
 695
 696         /* We'd set TX wordsize 8 bits and RX wordsize to 13 bits ... except
 697          * that even if the hardware can do that, the SPI controller driver
 698          * may not.  So we stick to very-portable 8 bit words, both RX and TX.
 699          */
 700         spi->bits_per_word = 8;
 701         spi->mode = SPI_MODE_0;
 702         err = spi_setup(spi);
 703         if (err < 0)
 704                 return err;
 705
 706         ts = kzalloc(sizeof(struct xpt2046), GFP_KERNEL);
 707         packet = kzalloc(sizeof(struct xpt2046_packet), GFP_KERNEL);
 708         input_dev = input_allocate_device();
 709         if (!ts || !packet || !input_dev) {
 710                 err = -ENOMEM;
 711                 goto err_free_mem;
 712         }
 713
 714         dev_set_drvdata(&spi->dev, ts);
 715
 716         ts->packet = packet;
 717         ts->spi = spi;
 718         ts->input = input_dev;
 719         ts->swap_xy = pdata->swap_xy;
 720
 721         hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 722         ts->timer.function = xpt2046_timer;
 723
 724         spin_lock_init(&ts->lock);
 725
 726         ts->model = pdata->model ? : 2046;
 727
 728         if (pdata->filter != NULL) {
 729                 if (pdata->filter_init != NULL) {
 730                         err = pdata->filter_init(pdata, &ts->filter_data);
 731                         if (err < 0)
 732                                 goto err_free_mem;
 733                 }
 734                 ts->filter = pdata->filter;
 735                 ts->filter_cleanup = pdata->filter_cleanup;
 736         } else if (pdata->debounce_max) {
 737                 ts->debounce_max = pdata->debounce_max;
 738                 if (ts->debounce_max < DEBOUNCE_REPTIME)
 739                         ts->debounce_max = DEBOUNCE_REPTIME;
 740                 ts->debounce_tol = pdata->debounce_tol;
 741                 ts->debounce_rep = pdata->debounce_rep;
 742                 ts->filter = xpt2046_debounce;
 743                 ts->filter_data = ts;
 744         } else
 745                 ts->filter = xpt2046_no_filter;
 746
 747         err = setup_pendown(spi, ts);
 748         if (err)
 749                 goto err_cleanup_filter;
 750
 751         if (pdata->penirq_recheck_delay_usecs)
 752                 ts->penirq_recheck_delay_usecs =
 753                                 pdata->penirq_recheck_delay_usecs;
 754
 755         ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
 756
 757         snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
 758         snprintf(ts->name, sizeof(ts->name), "XPT%d Touchscreen", ts->model);
 759
 760         input_dev->name = ts->name;
 761         input_dev->phys = ts->phys;
 762         input_dev->dev.parent = &spi->dev;
 763
 764         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 765         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 766         input_set_abs_params(input_dev, ABS_X,
 767                         pdata->x_min ? : 0,
 768                         pdata->x_max ? : MAX_12BIT,
 769                         0, 0);
 770         input_set_abs_params(input_dev, ABS_Y,
 771                         pdata->y_min ? : 0,
 772                         pdata->y_max ? : MAX_12BIT,
 773                         0, 0);
 774
 775         vref = pdata->keep_vref_on;
 776
 777         /* set up the transfers to read touchscreen state; this assumes we
 778          * use formula #2 for pressure, not #3.
 779          */
 780         m = &ts->msg[0];
 781         x = ts->xfer;
 782
 783         spi_message_init(m);
 784
 785         /* y- still on; turn on only y+ (and ADC) */
 786         packet->read_y = READ_Y(vref);
 787         x->tx_buf = &packet->read_y;
 788         x->len = 1;
 789         spi_message_add_tail(x, m);
 790
 791         x++;
 792         x->rx_buf = &packet->tc.y;
 793         x->len = 2;
 794         spi_message_add_tail(x, m);
 795
 796         m->complete = xpt2046_rx_val;
 797         m->context = ts;
 798
 799         m++;
 800         spi_message_init(m);
 801
 802         /* turn y- off, x+ on, then leave in lowpower */
 803         x++;
 804         packet->read_x = READ_X(vref);
 805         x->tx_buf = &packet->read_x;
 806         x->len = 1;
 807         spi_message_add_tail(x, m);
 808
 809         x++;
 810         x->rx_buf = &packet->tc.x;
 811         x->len = 2;
 812         spi_message_add_tail(x, m);
 813
 814         m->complete = xpt2046_rx_val;
 815         m->context = ts;
 816
 817         /* power down */
 818         m++;
 819         spi_message_init(m);
 820
 821         x++;
 822         packet->pwrdown = PWRDOWN;
 823         x->tx_buf = &packet->pwrdown;
 824         x->len = 1;
 825         spi_message_add_tail(x, m);
 826
 827         x++;
 828         x->rx_buf = &packet->dummy;
 829         x->len = 2;
 830         CS_CHANGE(*x);
 831         spi_message_add_tail(x, m);
 832
 833         m->complete = xpt2046_rx;
 834         m->context = ts;
 835
 836         ts->last_msg = m;
 837
 838         if (request_irq(spi->irq, xpt2046_irq, IRQF_TRIGGER_FALLING,
 839                         spi->dev.driver->name, ts)) {
 840                 printk("%s:trying pin change workaround on irq %d\n",__FUNCTION__,spi->irq);
 841                 err = request_irq(spi->irq, xpt2046_irq,
 842                                   IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 843                                   spi->dev.driver->name, ts);
 844                 if (err) {
 845                         dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
 846                         goto err_free_gpio;
 847                 }
 848         }
 849         xpt2046printk("***>%s:touchscreen irq %d\n",__FUNCTION__,spi->irq);
 850
 851         /* take a first sample, leaving nPENIRQ active and vREF off; avoid
 852          * the touchscreen, in case it's not connected.
 853          */
 854         xpt2046_read12_dfr(&spi->dev,READ_X(1));
 855
 856         err = input_register_device(input_dev);
 857         if (err)
 858                 goto err_remove_attr_group;
 859   printk("xpt2046_ts: driver initialized\n");
 860         return 0;
 861
 862  err_remove_attr_group:
 863         free_irq(spi->irq, ts);
 864  err_free_gpio:
 865         if (ts->gpio_pendown != -1)
 866                 gpio_free(ts->gpio_pendown);
 867  err_cleanup_filter:
 868         if (ts->filter_cleanup)
 869                 ts->filter_cleanup(ts->filter_data);
 870  err_free_mem:
 871         input_free_device(input_dev);
 872         kfree(packet);
 873         kfree(ts);
 874         return err;
 875 }
 876
 877 static int __devexit xpt2046_remove(struct spi_device *spi)
 878 {
 879         struct xpt2046          *ts = dev_get_drvdata(&spi->dev);
 880
 881         input_unregister_device(ts->input);
 882
 883         xpt2046_suspend(spi, PMSG_SUSPEND);
 884
 885         free_irq(ts->spi->irq, ts);
 886         /* suspend left the IRQ disabled */
 887         enable_irq(ts->spi->irq);
 888
 889         if (ts->gpio_pendown != -1)
 890                 gpio_free(ts->gpio_pendown);
 891
 892         if (ts->filter_cleanup)
 893                 ts->filter_cleanup(ts->filter_data);
 894
 895         kfree(ts->packet);
 896         kfree(ts);
 897
 898         dev_dbg(&spi->dev, "unregistered touchscreen\n");
 899         return 0;
 900 }
 901
 902 static struct spi_driver xpt2046_driver = {
 903         .driver = {
 904                 .name   = "xpt2046_ts",
 905                 .bus    = &spi_bus_type,
 906                 .owner  = THIS_MODULE,
 907         },
 908         .probe          = xpt2046_probe,
 909         .remove         = __devexit_p(xpt2046_remove),
 910         .suspend        = xpt2046_suspend,
 911         .resume         = xpt2046_resume,
 912 };
 913
 914 static int __init xpt2046_init(void)
 915 {
 916         return spi_register_driver(&xpt2046_driver);
 917 }
 918 module_init(xpt2046_init);
 919
 920 static void __exit xpt2046_exit(void)
 921 {
 922         spi_unregister_driver(&xpt2046_driver);
 923 }
 924 module_exit(xpt2046_exit);
 925
 926 MODULE_DESCRIPTION("rk2818 spi xpt2046 TouchScreen Driver");
 927 MODULE_LICENSE("GPL");
 928 MODULE_ALIAS("spi:xpt2046");