Merge commit 'v2.6.34-rc2' into perf/core
[linux-2.6-block.git] / drivers / input / serio / serio_raw.c
CommitLineData
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
27MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
28MODULE_DESCRIPTION(DRIVER_DESC);
29MODULE_LICENSE("GPL");
30
31#define SERIO_RAW_QUEUE_LEN 64
32struct 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
45struct serio_raw_list {
46 struct fasync_struct *fasync;
47 struct serio_raw *serio_raw;
48 struct list_head node;
49};
50
c4e32e9f 51static DEFINE_MUTEX(serio_raw_mutex);
1da177e4
LT
52static LIST_HEAD(serio_raw_list);
53static unsigned int serio_raw_no;
54
55/*********************************************************************
56 * Interface with userspace (file operations) *
57 *********************************************************************/
58
59static 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
66static 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
78static 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
c4e32e9f 84 retval = mutex_lock_interruptible(&serio_raw_mutex);
1da177e4 85 if (retval)
77554b4d 86 return retval;
1da177e4 87
77554b4d
TLSC
88 serio_raw = serio_raw_locate(iminor(inode));
89 if (!serio_raw) {
1da177e4
LT
90 retval = -ENODEV;
91 goto out;
92 }
93
94 if (!serio_raw->serio) {
95 retval = -ENODEV;
96 goto out;
97 }
98
77554b4d
TLSC
99 list = kzalloc(sizeof(struct serio_raw_list), GFP_KERNEL);
100 if (!list) {
1da177e4
LT
101 retval = -ENOMEM;
102 goto out;
103 }
104
1da177e4
LT
105 list->serio_raw = serio_raw;
106 file->private_data = list;
107
108 serio_raw->refcnt++;
109 list_add_tail(&list->node, &serio_raw->list);
110
111out:
c4e32e9f 112 mutex_unlock(&serio_raw_mutex);
1da177e4
LT
113 return retval;
114}
115
116static int serio_raw_cleanup(struct serio_raw *serio_raw)
117{
118 if (--serio_raw->refcnt == 0) {
119 misc_deregister(&serio_raw->dev);
120 list_del_init(&serio_raw->node);
121 kfree(serio_raw);
122
123 return 1;
124 }
125
126 return 0;
127}
128
129static int serio_raw_release(struct inode *inode, struct file *file)
130{
131 struct serio_raw_list *list = file->private_data;
132 struct serio_raw *serio_raw = list->serio_raw;
133
c4e32e9f 134 mutex_lock(&serio_raw_mutex);
1da177e4 135
1da177e4
LT
136 serio_raw_cleanup(serio_raw);
137
c4e32e9f 138 mutex_unlock(&serio_raw_mutex);
1da177e4
LT
139 return 0;
140}
141
142static int serio_raw_fetch_byte(struct serio_raw *serio_raw, char *c)
143{
144 unsigned long flags;
145 int empty;
146
147 spin_lock_irqsave(&serio_raw->serio->lock, flags);
148
149 empty = serio_raw->head == serio_raw->tail;
150 if (!empty) {
151 *c = serio_raw->queue[serio_raw->tail];
152 serio_raw->tail = (serio_raw->tail + 1) % SERIO_RAW_QUEUE_LEN;
153 }
154
155 spin_unlock_irqrestore(&serio_raw->serio->lock, flags);
156
157 return !empty;
158}
159
160static ssize_t serio_raw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
161{
162 struct serio_raw_list *list = file->private_data;
163 struct serio_raw *serio_raw = list->serio_raw;
4f179f71 164 char uninitialized_var(c);
1da177e4
LT
165 ssize_t retval = 0;
166
167 if (!serio_raw->serio)
168 return -ENODEV;
169
170 if (serio_raw->head == serio_raw->tail && (file->f_flags & O_NONBLOCK))
171 return -EAGAIN;
172
173 retval = wait_event_interruptible(list->serio_raw->wait,
174 serio_raw->head != serio_raw->tail || !serio_raw->serio);
175 if (retval)
176 return retval;
177
178 if (!serio_raw->serio)
179 return -ENODEV;
180
181 while (retval < count && serio_raw_fetch_byte(serio_raw, &c)) {
182 if (put_user(c, buffer++))
183 return -EFAULT;
184 retval++;
185 }
186
187 return retval;
188}
189
190static ssize_t serio_raw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
191{
192 struct serio_raw_list *list = file->private_data;
193 ssize_t written = 0;
194 int retval;
195 unsigned char c;
196
c4e32e9f 197 retval = mutex_lock_interruptible(&serio_raw_mutex);
1da177e4
LT
198 if (retval)
199 return retval;
200
201 if (!list->serio_raw->serio) {
202 retval = -ENODEV;
203 goto out;
204 }
205
206 if (count > 32)
207 count = 32;
208
209 while (count--) {
210 if (get_user(c, buffer++)) {
211 retval = -EFAULT;
212 goto out;
213 }
214 if (serio_write(list->serio_raw->serio, c)) {
215 retval = -EIO;
216 goto out;
217 }
218 written++;
219 };
220
221out:
c4e32e9f 222 mutex_unlock(&serio_raw_mutex);
1da177e4
LT
223 return written;
224}
225
226static unsigned int serio_raw_poll(struct file *file, poll_table *wait)
227{
228 struct serio_raw_list *list = file->private_data;
229
230 poll_wait(file, &list->serio_raw->wait, wait);
231
232 if (list->serio_raw->head != list->serio_raw->tail)
233 return POLLIN | POLLRDNORM;
234
235 return 0;
236}
237
2b8693c0 238static const struct file_operations serio_raw_fops = {
1da177e4
LT
239 .owner = THIS_MODULE,
240 .open = serio_raw_open,
241 .release = serio_raw_release,
242 .read = serio_raw_read,
243 .write = serio_raw_write,
244 .poll = serio_raw_poll,
245 .fasync = serio_raw_fasync,
246};
247
248
249/*********************************************************************
250 * Interface with serio port *
251 *********************************************************************/
252
253static irqreturn_t serio_raw_interrupt(struct serio *serio, unsigned char data,
7d12e780 254 unsigned int dfl)
1da177e4
LT
255{
256 struct serio_raw *serio_raw = serio_get_drvdata(serio);
257 struct serio_raw_list *list;
258 unsigned int head = serio_raw->head;
259
260 /* we are holding serio->lock here so we are prootected */
261 serio_raw->queue[head] = data;
262 head = (head + 1) % SERIO_RAW_QUEUE_LEN;
263 if (likely(head != serio_raw->tail)) {
264 serio_raw->head = head;
265 list_for_each_entry(list, &serio_raw->list, node)
266 kill_fasync(&list->fasync, SIGIO, POLL_IN);
267 wake_up_interruptible(&serio_raw->wait);
268 }
269
270 return IRQ_HANDLED;
271}
272
273static int serio_raw_connect(struct serio *serio, struct serio_driver *drv)
274{
275 struct serio_raw *serio_raw;
276 int err;
277
b39787a9 278 if (!(serio_raw = kzalloc(sizeof(struct serio_raw), GFP_KERNEL))) {
1da177e4
LT
279 printk(KERN_ERR "serio_raw.c: can't allocate memory for a device\n");
280 return -ENOMEM;
281 }
282
c4e32e9f 283 mutex_lock(&serio_raw_mutex);
1da177e4 284
1da177e4
LT
285 snprintf(serio_raw->name, sizeof(serio_raw->name), "serio_raw%d", serio_raw_no++);
286 serio_raw->refcnt = 1;
287 serio_raw->serio = serio;
288 INIT_LIST_HEAD(&serio_raw->list);
289 init_waitqueue_head(&serio_raw->wait);
290
291 serio_set_drvdata(serio, serio_raw);
292
293 err = serio_open(serio, drv);
294 if (err)
295 goto out_free;
296
297 list_add_tail(&serio_raw->node, &serio_raw_list);
298
299 serio_raw->dev.minor = PSMOUSE_MINOR;
300 serio_raw->dev.name = serio_raw->name;
94fbcded 301 serio_raw->dev.parent = &serio->dev;
1da177e4
LT
302 serio_raw->dev.fops = &serio_raw_fops;
303
304 err = misc_register(&serio_raw->dev);
305 if (err) {
306 serio_raw->dev.minor = MISC_DYNAMIC_MINOR;
307 err = misc_register(&serio_raw->dev);
308 }
309
310 if (err) {
311 printk(KERN_INFO "serio_raw: failed to register raw access device for %s\n",
312 serio->phys);
313 goto out_close;
314 }
315
316 printk(KERN_INFO "serio_raw: raw access enabled on %s (%s, minor %d)\n",
317 serio->phys, serio_raw->name, serio_raw->dev.minor);
318 goto out;
319
320out_close:
321 serio_close(serio);
322 list_del_init(&serio_raw->node);
323out_free:
324 serio_set_drvdata(serio, NULL);
325 kfree(serio_raw);
326out:
c4e32e9f 327 mutex_unlock(&serio_raw_mutex);
1da177e4
LT
328 return err;
329}
330
331static int serio_raw_reconnect(struct serio *serio)
332{
333 struct serio_raw *serio_raw = serio_get_drvdata(serio);
334 struct serio_driver *drv = serio->drv;
335
336 if (!drv || !serio_raw) {
337 printk(KERN_DEBUG "serio_raw: reconnect request, but serio is disconnected, ignoring...\n");
338 return -1;
339 }
340
341 /*
342 * Nothing needs to be done here, we just need this method to
343 * keep the same device.
344 */
345 return 0;
346}
347
348static void serio_raw_disconnect(struct serio *serio)
349{
350 struct serio_raw *serio_raw;
351
c4e32e9f 352 mutex_lock(&serio_raw_mutex);
1da177e4
LT
353
354 serio_raw = serio_get_drvdata(serio);
355
356 serio_close(serio);
357 serio_set_drvdata(serio, NULL);
358
359 serio_raw->serio = NULL;
360 if (!serio_raw_cleanup(serio_raw))
361 wake_up_interruptible(&serio_raw->wait);
362
c4e32e9f 363 mutex_unlock(&serio_raw_mutex);
1da177e4
LT
364}
365
366static struct serio_device_id serio_raw_serio_ids[] = {
367 {
368 .type = SERIO_8042,
369 .proto = SERIO_ANY,
370 .id = SERIO_ANY,
371 .extra = SERIO_ANY,
372 },
d19497e2
NV
373 {
374 .type = SERIO_8042_XL,
375 .proto = SERIO_ANY,
376 .id = SERIO_ANY,
377 .extra = SERIO_ANY,
378 },
1da177e4
LT
379 { 0 }
380};
381
382MODULE_DEVICE_TABLE(serio, serio_raw_serio_ids);
383
384static struct serio_driver serio_raw_drv = {
385 .driver = {
386 .name = "serio_raw",
387 },
388 .description = DRIVER_DESC,
389 .id_table = serio_raw_serio_ids,
390 .interrupt = serio_raw_interrupt,
391 .connect = serio_raw_connect,
392 .reconnect = serio_raw_reconnect,
393 .disconnect = serio_raw_disconnect,
394 .manual_bind = 1,
395};
396
397static int __init serio_raw_init(void)
398{
153a9df0 399 return serio_register_driver(&serio_raw_drv);
1da177e4
LT
400}
401
402static void __exit serio_raw_exit(void)
403{
404 serio_unregister_driver(&serio_raw_drv);
405}
406
407module_init(serio_raw_init);
408module_exit(serio_raw_exit);