2 * Copyright (C) 2007 Google, Inc.
3 * Copyright (C) 2012 Intel, Inc.
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
16 #include <linux/console.h>
17 #include <linux/interrupt.h>
18 #include <linux/platform_device.h>
19 #include <linux/tty.h>
20 #include <linux/tty_flip.h>
21 #include <linux/slab.h>
23 #include <linux/module.h>
24 #include <linux/goldfish.h>
27 GOLDFISH_TTY_PUT_CHAR = 0x00,
28 GOLDFISH_TTY_BYTES_READY = 0x04,
29 GOLDFISH_TTY_CMD = 0x08,
31 GOLDFISH_TTY_DATA_PTR = 0x10,
32 GOLDFISH_TTY_DATA_LEN = 0x14,
33 GOLDFISH_TTY_DATA_PTR_HIGH = 0x18,
35 GOLDFISH_TTY_CMD_INT_DISABLE = 0,
36 GOLDFISH_TTY_CMD_INT_ENABLE = 1,
37 GOLDFISH_TTY_CMD_WRITE_BUFFER = 2,
38 GOLDFISH_TTY_CMD_READ_BUFFER = 3,
47 struct console console;
50 static DEFINE_MUTEX(goldfish_tty_lock);
51 static struct tty_driver *goldfish_tty_driver;
52 static u32 goldfish_tty_line_count = 8;
53 static u32 goldfish_tty_current_line_count;
54 static struct goldfish_tty *goldfish_ttys;
56 static void goldfish_tty_do_write(int line, const char *buf, unsigned count)
58 unsigned long irq_flags;
59 struct goldfish_tty *qtty = &goldfish_ttys[line];
60 void __iomem *base = qtty->base;
61 spin_lock_irqsave(&qtty->lock, irq_flags);
62 gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
63 base + GOLDFISH_TTY_DATA_PTR_HIGH);
64 writel(count, base + GOLDFISH_TTY_DATA_LEN);
65 writel(GOLDFISH_TTY_CMD_WRITE_BUFFER, base + GOLDFISH_TTY_CMD);
66 spin_unlock_irqrestore(&qtty->lock, irq_flags);
69 static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id)
71 struct platform_device *pdev = dev_id;
72 struct goldfish_tty *qtty = &goldfish_ttys[pdev->id];
73 void __iomem *base = qtty->base;
74 unsigned long irq_flags;
78 count = readl(base + GOLDFISH_TTY_BYTES_READY);
82 count = tty_prepare_flip_string(&qtty->port, &buf, count);
83 spin_lock_irqsave(&qtty->lock, irq_flags);
84 gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
85 base + GOLDFISH_TTY_DATA_PTR_HIGH);
86 writel(count, base + GOLDFISH_TTY_DATA_LEN);
87 writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD);
88 spin_unlock_irqrestore(&qtty->lock, irq_flags);
89 tty_schedule_flip(&qtty->port);
93 static int goldfish_tty_activate(struct tty_port *port, struct tty_struct *tty)
95 struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
97 writel(GOLDFISH_TTY_CMD_INT_ENABLE, qtty->base + GOLDFISH_TTY_CMD);
101 static void goldfish_tty_shutdown(struct tty_port *port)
103 struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
105 writel(GOLDFISH_TTY_CMD_INT_DISABLE, qtty->base + GOLDFISH_TTY_CMD);
108 static int goldfish_tty_open(struct tty_struct *tty, struct file *filp)
110 struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
111 return tty_port_open(&qtty->port, tty, filp);
114 static void goldfish_tty_close(struct tty_struct *tty, struct file *filp)
116 tty_port_close(tty->port, tty, filp);
119 static void goldfish_tty_hangup(struct tty_struct *tty)
121 tty_port_hangup(tty->port);
124 static int goldfish_tty_write(struct tty_struct *tty, const unsigned char *buf,
127 goldfish_tty_do_write(tty->index, buf, count);
131 static int goldfish_tty_write_room(struct tty_struct *tty)
136 static int goldfish_tty_chars_in_buffer(struct tty_struct *tty)
138 struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
139 void __iomem *base = qtty->base;
140 return readl(base + GOLDFISH_TTY_BYTES_READY);
143 static void goldfish_tty_console_write(struct console *co, const char *b,
146 goldfish_tty_do_write(co->index, b, count);
149 static struct tty_driver *goldfish_tty_console_device(struct console *c,
153 return goldfish_tty_driver;
156 static int goldfish_tty_console_setup(struct console *co, char *options)
158 if ((unsigned)co->index >= goldfish_tty_line_count)
160 if (!goldfish_ttys[co->index].base)
165 static struct tty_port_operations goldfish_port_ops = {
166 .activate = goldfish_tty_activate,
167 .shutdown = goldfish_tty_shutdown
170 static const struct tty_operations goldfish_tty_ops = {
171 .open = goldfish_tty_open,
172 .close = goldfish_tty_close,
173 .hangup = goldfish_tty_hangup,
174 .write = goldfish_tty_write,
175 .write_room = goldfish_tty_write_room,
176 .chars_in_buffer = goldfish_tty_chars_in_buffer,
179 static int goldfish_tty_create_driver(void)
182 struct tty_driver *tty;
184 goldfish_ttys = kzalloc(sizeof(*goldfish_ttys) *
185 goldfish_tty_line_count, GFP_KERNEL);
186 if (goldfish_ttys == NULL) {
188 goto err_alloc_goldfish_ttys_failed;
190 tty = alloc_tty_driver(goldfish_tty_line_count);
193 goto err_alloc_tty_driver_failed;
195 tty->driver_name = "goldfish";
197 tty->type = TTY_DRIVER_TYPE_SERIAL;
198 tty->subtype = SERIAL_TYPE_NORMAL;
199 tty->init_termios = tty_std_termios;
200 tty->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
201 TTY_DRIVER_DYNAMIC_DEV;
202 tty_set_operations(tty, &goldfish_tty_ops);
203 ret = tty_register_driver(tty);
205 goto err_tty_register_driver_failed;
207 goldfish_tty_driver = tty;
210 err_tty_register_driver_failed:
212 err_alloc_tty_driver_failed:
213 kfree(goldfish_ttys);
214 goldfish_ttys = NULL;
215 err_alloc_goldfish_ttys_failed:
219 static void goldfish_tty_delete_driver(void)
221 tty_unregister_driver(goldfish_tty_driver);
222 put_tty_driver(goldfish_tty_driver);
223 goldfish_tty_driver = NULL;
224 kfree(goldfish_ttys);
225 goldfish_ttys = NULL;
228 static int goldfish_tty_probe(struct platform_device *pdev)
230 struct goldfish_tty *qtty;
233 struct device *ttydev;
237 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
241 base = ioremap(r->start, 0x1000);
243 pr_err("goldfish_tty: unable to remap base\n");
245 r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
251 if (pdev->id >= goldfish_tty_line_count)
254 mutex_lock(&goldfish_tty_lock);
255 if (goldfish_tty_current_line_count == 0) {
256 ret = goldfish_tty_create_driver();
258 goto err_create_driver_failed;
260 goldfish_tty_current_line_count++;
262 qtty = &goldfish_ttys[pdev->id];
263 spin_lock_init(&qtty->lock);
264 tty_port_init(&qtty->port);
265 qtty->port.ops = &goldfish_port_ops;
269 writel(GOLDFISH_TTY_CMD_INT_DISABLE, base + GOLDFISH_TTY_CMD);
271 ret = request_irq(irq, goldfish_tty_interrupt, IRQF_SHARED,
272 "goldfish_tty", pdev);
274 goto err_request_irq_failed;
277 ttydev = tty_port_register_device(&qtty->port, goldfish_tty_driver,
278 pdev->id, &pdev->dev);
279 if (IS_ERR(ttydev)) {
280 ret = PTR_ERR(ttydev);
281 goto err_tty_register_device_failed;
284 strcpy(qtty->console.name, "ttyGF");
285 qtty->console.write = goldfish_tty_console_write;
286 qtty->console.device = goldfish_tty_console_device;
287 qtty->console.setup = goldfish_tty_console_setup;
288 qtty->console.flags = CON_PRINTBUFFER;
289 qtty->console.index = pdev->id;
290 register_console(&qtty->console);
292 mutex_unlock(&goldfish_tty_lock);
295 err_tty_register_device_failed:
297 err_request_irq_failed:
298 goldfish_tty_current_line_count--;
299 if (goldfish_tty_current_line_count == 0)
300 goldfish_tty_delete_driver();
301 err_create_driver_failed:
302 mutex_unlock(&goldfish_tty_lock);
308 static int goldfish_tty_remove(struct platform_device *pdev)
310 struct goldfish_tty *qtty;
312 mutex_lock(&goldfish_tty_lock);
314 qtty = &goldfish_ttys[pdev->id];
315 unregister_console(&qtty->console);
316 tty_unregister_device(goldfish_tty_driver, pdev->id);
319 free_irq(qtty->irq, pdev);
320 goldfish_tty_current_line_count--;
321 if (goldfish_tty_current_line_count == 0)
322 goldfish_tty_delete_driver();
323 mutex_unlock(&goldfish_tty_lock);
327 static struct platform_driver goldfish_tty_platform_driver = {
328 .probe = goldfish_tty_probe,
329 .remove = goldfish_tty_remove,
331 .name = "goldfish_tty"
335 module_platform_driver(goldfish_tty_platform_driver);
337 MODULE_LICENSE("GPL v2");