Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Raw serio device providing access to a raw byte stream from underlying | |
3 | * serio port. Closely emulates behavior of pre-2.6 /dev/psaux device | |
4 | * | |
5 | * Copyright (c) 2004 Dmitry Torokhov | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License version 2 as published by | |
9 | * the Free Software Foundation. | |
10 | */ | |
11 | ||
d43c36dc | 12 | #include <linux/sched.h> |
1da177e4 | 13 | #include <linux/slab.h> |
9edca64b | 14 | #include <linux/smp_lock.h> |
1da177e4 LT |
15 | #include <linux/poll.h> |
16 | #include <linux/module.h> | |
17 | #include <linux/serio.h> | |
18 | #include <linux/init.h> | |
19 | #include <linux/major.h> | |
20 | #include <linux/device.h> | |
1da177e4 LT |
21 | #include <linux/miscdevice.h> |
22 | #include <linux/wait.h> | |
c4e32e9f | 23 | #include <linux/mutex.h> |
1da177e4 LT |
24 | |
25 | #define DRIVER_DESC "Raw serio driver" | |
26 | ||
27 | MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); | |
28 | MODULE_DESCRIPTION(DRIVER_DESC); | |
29 | MODULE_LICENSE("GPL"); | |
30 | ||
31 | #define SERIO_RAW_QUEUE_LEN 64 | |
32 | struct serio_raw { | |
33 | unsigned char queue[SERIO_RAW_QUEUE_LEN]; | |
34 | unsigned int tail, head; | |
35 | ||
36 | char name[16]; | |
37 | unsigned int refcnt; | |
38 | struct serio *serio; | |
39 | struct miscdevice dev; | |
40 | wait_queue_head_t wait; | |
41 | struct list_head list; | |
42 | struct list_head node; | |
43 | }; | |
44 | ||
45 | struct serio_raw_list { | |
46 | struct fasync_struct *fasync; | |
47 | struct serio_raw *serio_raw; | |
48 | struct list_head node; | |
49 | }; | |
50 | ||
c4e32e9f | 51 | static DEFINE_MUTEX(serio_raw_mutex); |
1da177e4 LT |
52 | static LIST_HEAD(serio_raw_list); |
53 | static unsigned int serio_raw_no; | |
54 | ||
55 | /********************************************************************* | |
56 | * Interface with userspace (file operations) * | |
57 | *********************************************************************/ | |
58 | ||
59 | static int serio_raw_fasync(int fd, struct file *file, int on) | |
60 | { | |
61 | struct serio_raw_list *list = file->private_data; | |
1da177e4 | 62 | |
60aa4924 | 63 | return fasync_helper(fd, file, on, &list->fasync); |
1da177e4 LT |
64 | } |
65 | ||
66 | static struct serio_raw *serio_raw_locate(int minor) | |
67 | { | |
68 | struct serio_raw *serio_raw; | |
69 | ||
70 | list_for_each_entry(serio_raw, &serio_raw_list, node) { | |
71 | if (serio_raw->dev.minor == minor) | |
72 | return serio_raw; | |
73 | } | |
74 | ||
75 | return NULL; | |
76 | } | |
77 | ||
78 | static int serio_raw_open(struct inode *inode, struct file *file) | |
79 | { | |
80 | struct serio_raw *serio_raw; | |
81 | struct serio_raw_list *list; | |
82 | int retval = 0; | |
83 | ||
9edca64b | 84 | lock_kernel(); |
c4e32e9f | 85 | retval = mutex_lock_interruptible(&serio_raw_mutex); |
1da177e4 | 86 | if (retval) |
9edca64b | 87 | goto out_bkl; |
1da177e4 LT |
88 | |
89 | if (!(serio_raw = serio_raw_locate(iminor(inode)))) { | |
90 | retval = -ENODEV; | |
91 | goto out; | |
92 | } | |
93 | ||
94 | if (!serio_raw->serio) { | |
95 | retval = -ENODEV; | |
96 | goto out; | |
97 | } | |
98 | ||
b39787a9 | 99 | if (!(list = kzalloc(sizeof(struct serio_raw_list), GFP_KERNEL))) { |
1da177e4 LT |
100 | retval = -ENOMEM; |
101 | goto out; | |
102 | } | |
103 | ||
1da177e4 LT |
104 | list->serio_raw = serio_raw; |
105 | file->private_data = list; | |
106 | ||
107 | serio_raw->refcnt++; | |
108 | list_add_tail(&list->node, &serio_raw->list); | |
109 | ||
110 | out: | |
c4e32e9f | 111 | mutex_unlock(&serio_raw_mutex); |
9edca64b AB |
112 | out_bkl: |
113 | unlock_kernel(); | |
1da177e4 LT |
114 | return retval; |
115 | } | |
116 | ||
117 | static int serio_raw_cleanup(struct serio_raw *serio_raw) | |
118 | { | |
119 | if (--serio_raw->refcnt == 0) { | |
120 | misc_deregister(&serio_raw->dev); | |
121 | list_del_init(&serio_raw->node); | |
122 | kfree(serio_raw); | |
123 | ||
124 | return 1; | |
125 | } | |
126 | ||
127 | return 0; | |
128 | } | |
129 | ||
130 | static int serio_raw_release(struct inode *inode, struct file *file) | |
131 | { | |
132 | struct serio_raw_list *list = file->private_data; | |
133 | struct serio_raw *serio_raw = list->serio_raw; | |
134 | ||
c4e32e9f | 135 | mutex_lock(&serio_raw_mutex); |
1da177e4 | 136 | |
1da177e4 LT |
137 | serio_raw_cleanup(serio_raw); |
138 | ||
c4e32e9f | 139 | mutex_unlock(&serio_raw_mutex); |
1da177e4 LT |
140 | return 0; |
141 | } | |
142 | ||
143 | static int serio_raw_fetch_byte(struct serio_raw *serio_raw, char *c) | |
144 | { | |
145 | unsigned long flags; | |
146 | int empty; | |
147 | ||
148 | spin_lock_irqsave(&serio_raw->serio->lock, flags); | |
149 | ||
150 | empty = serio_raw->head == serio_raw->tail; | |
151 | if (!empty) { | |
152 | *c = serio_raw->queue[serio_raw->tail]; | |
153 | serio_raw->tail = (serio_raw->tail + 1) % SERIO_RAW_QUEUE_LEN; | |
154 | } | |
155 | ||
156 | spin_unlock_irqrestore(&serio_raw->serio->lock, flags); | |
157 | ||
158 | return !empty; | |
159 | } | |
160 | ||
161 | static ssize_t serio_raw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) | |
162 | { | |
163 | struct serio_raw_list *list = file->private_data; | |
164 | struct serio_raw *serio_raw = list->serio_raw; | |
4f179f71 | 165 | char uninitialized_var(c); |
1da177e4 LT |
166 | ssize_t retval = 0; |
167 | ||
168 | if (!serio_raw->serio) | |
169 | return -ENODEV; | |
170 | ||
171 | if (serio_raw->head == serio_raw->tail && (file->f_flags & O_NONBLOCK)) | |
172 | return -EAGAIN; | |
173 | ||
174 | retval = wait_event_interruptible(list->serio_raw->wait, | |
175 | serio_raw->head != serio_raw->tail || !serio_raw->serio); | |
176 | if (retval) | |
177 | return retval; | |
178 | ||
179 | if (!serio_raw->serio) | |
180 | return -ENODEV; | |
181 | ||
182 | while (retval < count && serio_raw_fetch_byte(serio_raw, &c)) { | |
183 | if (put_user(c, buffer++)) | |
184 | return -EFAULT; | |
185 | retval++; | |
186 | } | |
187 | ||
188 | return retval; | |
189 | } | |
190 | ||
191 | static ssize_t serio_raw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) | |
192 | { | |
193 | struct serio_raw_list *list = file->private_data; | |
194 | ssize_t written = 0; | |
195 | int retval; | |
196 | unsigned char c; | |
197 | ||
c4e32e9f | 198 | retval = mutex_lock_interruptible(&serio_raw_mutex); |
1da177e4 LT |
199 | if (retval) |
200 | return retval; | |
201 | ||
202 | if (!list->serio_raw->serio) { | |
203 | retval = -ENODEV; | |
204 | goto out; | |
205 | } | |
206 | ||
207 | if (count > 32) | |
208 | count = 32; | |
209 | ||
210 | while (count--) { | |
211 | if (get_user(c, buffer++)) { | |
212 | retval = -EFAULT; | |
213 | goto out; | |
214 | } | |
215 | if (serio_write(list->serio_raw->serio, c)) { | |
216 | retval = -EIO; | |
217 | goto out; | |
218 | } | |
219 | written++; | |
220 | }; | |
221 | ||
222 | out: | |
c4e32e9f | 223 | mutex_unlock(&serio_raw_mutex); |
1da177e4 LT |
224 | return written; |
225 | } | |
226 | ||
227 | static unsigned int serio_raw_poll(struct file *file, poll_table *wait) | |
228 | { | |
229 | struct serio_raw_list *list = file->private_data; | |
230 | ||
231 | poll_wait(file, &list->serio_raw->wait, wait); | |
232 | ||
233 | if (list->serio_raw->head != list->serio_raw->tail) | |
234 | return POLLIN | POLLRDNORM; | |
235 | ||
236 | return 0; | |
237 | } | |
238 | ||
2b8693c0 | 239 | static const struct file_operations serio_raw_fops = { |
1da177e4 LT |
240 | .owner = THIS_MODULE, |
241 | .open = serio_raw_open, | |
242 | .release = serio_raw_release, | |
243 | .read = serio_raw_read, | |
244 | .write = serio_raw_write, | |
245 | .poll = serio_raw_poll, | |
246 | .fasync = serio_raw_fasync, | |
247 | }; | |
248 | ||
249 | ||
250 | /********************************************************************* | |
251 | * Interface with serio port * | |
252 | *********************************************************************/ | |
253 | ||
254 | static irqreturn_t serio_raw_interrupt(struct serio *serio, unsigned char data, | |
7d12e780 | 255 | unsigned int dfl) |
1da177e4 LT |
256 | { |
257 | struct serio_raw *serio_raw = serio_get_drvdata(serio); | |
258 | struct serio_raw_list *list; | |
259 | unsigned int head = serio_raw->head; | |
260 | ||
261 | /* we are holding serio->lock here so we are prootected */ | |
262 | serio_raw->queue[head] = data; | |
263 | head = (head + 1) % SERIO_RAW_QUEUE_LEN; | |
264 | if (likely(head != serio_raw->tail)) { | |
265 | serio_raw->head = head; | |
266 | list_for_each_entry(list, &serio_raw->list, node) | |
267 | kill_fasync(&list->fasync, SIGIO, POLL_IN); | |
268 | wake_up_interruptible(&serio_raw->wait); | |
269 | } | |
270 | ||
271 | return IRQ_HANDLED; | |
272 | } | |
273 | ||
274 | static int serio_raw_connect(struct serio *serio, struct serio_driver *drv) | |
275 | { | |
276 | struct serio_raw *serio_raw; | |
277 | int err; | |
278 | ||
b39787a9 | 279 | if (!(serio_raw = kzalloc(sizeof(struct serio_raw), GFP_KERNEL))) { |
1da177e4 LT |
280 | printk(KERN_ERR "serio_raw.c: can't allocate memory for a device\n"); |
281 | return -ENOMEM; | |
282 | } | |
283 | ||
c4e32e9f | 284 | mutex_lock(&serio_raw_mutex); |
1da177e4 | 285 | |
1da177e4 LT |
286 | snprintf(serio_raw->name, sizeof(serio_raw->name), "serio_raw%d", serio_raw_no++); |
287 | serio_raw->refcnt = 1; | |
288 | serio_raw->serio = serio; | |
289 | INIT_LIST_HEAD(&serio_raw->list); | |
290 | init_waitqueue_head(&serio_raw->wait); | |
291 | ||
292 | serio_set_drvdata(serio, serio_raw); | |
293 | ||
294 | err = serio_open(serio, drv); | |
295 | if (err) | |
296 | goto out_free; | |
297 | ||
298 | list_add_tail(&serio_raw->node, &serio_raw_list); | |
299 | ||
300 | serio_raw->dev.minor = PSMOUSE_MINOR; | |
301 | serio_raw->dev.name = serio_raw->name; | |
94fbcded | 302 | serio_raw->dev.parent = &serio->dev; |
1da177e4 LT |
303 | serio_raw->dev.fops = &serio_raw_fops; |
304 | ||
305 | err = misc_register(&serio_raw->dev); | |
306 | if (err) { | |
307 | serio_raw->dev.minor = MISC_DYNAMIC_MINOR; | |
308 | err = misc_register(&serio_raw->dev); | |
309 | } | |
310 | ||
311 | if (err) { | |
312 | printk(KERN_INFO "serio_raw: failed to register raw access device for %s\n", | |
313 | serio->phys); | |
314 | goto out_close; | |
315 | } | |
316 | ||
317 | printk(KERN_INFO "serio_raw: raw access enabled on %s (%s, minor %d)\n", | |
318 | serio->phys, serio_raw->name, serio_raw->dev.minor); | |
319 | goto out; | |
320 | ||
321 | out_close: | |
322 | serio_close(serio); | |
323 | list_del_init(&serio_raw->node); | |
324 | out_free: | |
325 | serio_set_drvdata(serio, NULL); | |
326 | kfree(serio_raw); | |
327 | out: | |
c4e32e9f | 328 | mutex_unlock(&serio_raw_mutex); |
1da177e4 LT |
329 | return err; |
330 | } | |
331 | ||
332 | static int serio_raw_reconnect(struct serio *serio) | |
333 | { | |
334 | struct serio_raw *serio_raw = serio_get_drvdata(serio); | |
335 | struct serio_driver *drv = serio->drv; | |
336 | ||
337 | if (!drv || !serio_raw) { | |
338 | printk(KERN_DEBUG "serio_raw: reconnect request, but serio is disconnected, ignoring...\n"); | |
339 | return -1; | |
340 | } | |
341 | ||
342 | /* | |
343 | * Nothing needs to be done here, we just need this method to | |
344 | * keep the same device. | |
345 | */ | |
346 | return 0; | |
347 | } | |
348 | ||
349 | static void serio_raw_disconnect(struct serio *serio) | |
350 | { | |
351 | struct serio_raw *serio_raw; | |
352 | ||
c4e32e9f | 353 | mutex_lock(&serio_raw_mutex); |
1da177e4 LT |
354 | |
355 | serio_raw = serio_get_drvdata(serio); | |
356 | ||
357 | serio_close(serio); | |
358 | serio_set_drvdata(serio, NULL); | |
359 | ||
360 | serio_raw->serio = NULL; | |
361 | if (!serio_raw_cleanup(serio_raw)) | |
362 | wake_up_interruptible(&serio_raw->wait); | |
363 | ||
c4e32e9f | 364 | mutex_unlock(&serio_raw_mutex); |
1da177e4 LT |
365 | } |
366 | ||
367 | static struct serio_device_id serio_raw_serio_ids[] = { | |
368 | { | |
369 | .type = SERIO_8042, | |
370 | .proto = SERIO_ANY, | |
371 | .id = SERIO_ANY, | |
372 | .extra = SERIO_ANY, | |
373 | }, | |
d19497e2 NV |
374 | { |
375 | .type = SERIO_8042_XL, | |
376 | .proto = SERIO_ANY, | |
377 | .id = SERIO_ANY, | |
378 | .extra = SERIO_ANY, | |
379 | }, | |
1da177e4 LT |
380 | { 0 } |
381 | }; | |
382 | ||
383 | MODULE_DEVICE_TABLE(serio, serio_raw_serio_ids); | |
384 | ||
385 | static struct serio_driver serio_raw_drv = { | |
386 | .driver = { | |
387 | .name = "serio_raw", | |
388 | }, | |
389 | .description = DRIVER_DESC, | |
390 | .id_table = serio_raw_serio_ids, | |
391 | .interrupt = serio_raw_interrupt, | |
392 | .connect = serio_raw_connect, | |
393 | .reconnect = serio_raw_reconnect, | |
394 | .disconnect = serio_raw_disconnect, | |
395 | .manual_bind = 1, | |
396 | }; | |
397 | ||
398 | static int __init serio_raw_init(void) | |
399 | { | |
153a9df0 | 400 | return serio_register_driver(&serio_raw_drv); |
1da177e4 LT |
401 | } |
402 | ||
403 | static void __exit serio_raw_exit(void) | |
404 | { | |
405 | serio_unregister_driver(&serio_raw_drv); | |
406 | } | |
407 | ||
408 | module_init(serio_raw_init); | |
409 | module_exit(serio_raw_exit); |