2 * HID raw devices, giving access to raw HID events.
4 * In comparison to hiddev, this device does not process the
5 * hid events at all (no parsing, no lookups). This lets applications
6 * to work on raw hid events as they want to, and avoids a need to
7 * use a transport-specific userspace libhid/libusb libraries.
9 * Copyright (c) 2007 Jiri Kosina
13 * This program is free software; you can redistribute it and/or modify it
14 * under the terms and conditions of the GNU General Public License,
15 * version 2, as published by the Free Software Foundation.
17 * You should have received a copy of the GNU General Public License along with
18 * this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/kernel.h>
26 #include <linux/init.h>
27 #include <linux/cdev.h>
28 #include <linux/poll.h>
29 #include <linux/device.h>
30 #include <linux/major.h>
31 #include <linux/slab.h>
32 #include <linux/hid.h>
33 #include <linux/mutex.h>
34 #include <linux/sched.h>
35 #include <linux/smp_lock.h>
37 #include <linux/hidraw.h>
39 static int hidraw_major
;
40 static struct cdev hidraw_cdev
;
41 static struct class *hidraw_class
;
42 static struct hidraw
*hidraw_table
[HIDRAW_MAX_DEVICES
];
43 static DEFINE_MUTEX(minors_lock
);
45 static ssize_t
hidraw_read(struct file
*file
, char __user
*buffer
, size_t count
, loff_t
*ppos
)
47 struct hidraw_list
*list
= file
->private_data
;
49 DECLARE_WAITQUEUE(wait
, current
);
51 mutex_lock(&list
->read_mutex
);
54 if (list
->head
== list
->tail
) {
55 add_wait_queue(&list
->hidraw
->wait
, &wait
);
56 set_current_state(TASK_INTERRUPTIBLE
);
58 while (list
->head
== list
->tail
) {
59 if (file
->f_flags
& O_NONBLOCK
) {
63 if (signal_pending(current
)) {
67 if (!list
->hidraw
->exist
) {
72 /* allow O_NONBLOCK to work well from other threads */
73 mutex_unlock(&list
->read_mutex
);
75 mutex_lock(&list
->read_mutex
);
76 set_current_state(TASK_INTERRUPTIBLE
);
79 set_current_state(TASK_RUNNING
);
80 remove_wait_queue(&list
->hidraw
->wait
, &wait
);
86 len
= list
->buffer
[list
->tail
].len
> count
?
87 count
: list
->buffer
[list
->tail
].len
;
89 if (copy_to_user(buffer
, list
->buffer
[list
->tail
].value
, len
)) {
95 kfree(list
->buffer
[list
->tail
].value
);
96 list
->tail
= (list
->tail
+ 1) & (HIDRAW_BUFFER_SIZE
- 1);
99 mutex_unlock(&list
->read_mutex
);
103 /* the first byte is expected to be a report number */
104 static ssize_t
hidraw_write(struct file
*file
, const char __user
*buffer
, size_t count
, loff_t
*ppos
)
106 unsigned int minor
= iminor(file
->f_path
.dentry
->d_inode
);
107 struct hid_device
*dev
;
111 mutex_lock(&minors_lock
);
113 if (!hidraw_table
[minor
]) {
118 dev
= hidraw_table
[minor
]->hid
;
120 if (!dev
->hid_output_raw_report
) {
125 if (count
> HID_MAX_BUFFER_SIZE
) {
126 printk(KERN_WARNING
"hidraw: pid %d passed too large report\n",
127 task_pid_nr(current
));
133 printk(KERN_WARNING
"hidraw: pid %d passed too short report\n",
134 task_pid_nr(current
));
139 buf
= kmalloc(count
* sizeof(__u8
), GFP_KERNEL
);
145 if (copy_from_user(buf
, buffer
, count
)) {
150 ret
= dev
->hid_output_raw_report(dev
, buf
, count
, HID_OUTPUT_REPORT
);
154 mutex_unlock(&minors_lock
);
158 static unsigned int hidraw_poll(struct file
*file
, poll_table
*wait
)
160 struct hidraw_list
*list
= file
->private_data
;
162 poll_wait(file
, &list
->hidraw
->wait
, wait
);
163 if (list
->head
!= list
->tail
)
164 return POLLIN
| POLLRDNORM
;
165 if (!list
->hidraw
->exist
)
166 return POLLERR
| POLLHUP
;
170 static int hidraw_open(struct inode
*inode
, struct file
*file
)
172 unsigned int minor
= iminor(inode
);
174 struct hidraw_list
*list
;
177 if (!(list
= kzalloc(sizeof(struct hidraw_list
), GFP_KERNEL
))) {
182 mutex_lock(&minors_lock
);
183 if (!hidraw_table
[minor
]) {
189 list
->hidraw
= hidraw_table
[minor
];
190 mutex_init(&list
->read_mutex
);
191 list_add_tail(&list
->node
, &hidraw_table
[minor
]->list
);
192 file
->private_data
= list
;
194 dev
= hidraw_table
[minor
];
196 if (dev
->hid
->ll_driver
->power
) {
197 err
= dev
->hid
->ll_driver
->power(dev
->hid
, PM_HINT_FULLON
);
201 err
= dev
->hid
->ll_driver
->open(dev
->hid
);
203 if (dev
->hid
->ll_driver
->power
)
204 dev
->hid
->ll_driver
->power(dev
->hid
, PM_HINT_NORMAL
);
210 mutex_unlock(&minors_lock
);
216 static int hidraw_release(struct inode
* inode
, struct file
* file
)
218 unsigned int minor
= iminor(inode
);
220 struct hidraw_list
*list
= file
->private_data
;
223 mutex_lock(&minors_lock
);
224 if (!hidraw_table
[minor
]) {
229 list_del(&list
->node
);
230 dev
= hidraw_table
[minor
];
232 if (list
->hidraw
->exist
) {
233 if (dev
->hid
->ll_driver
->power
)
234 dev
->hid
->ll_driver
->power(dev
->hid
, PM_HINT_NORMAL
);
235 dev
->hid
->ll_driver
->close(dev
->hid
);
243 mutex_unlock(&minors_lock
);
248 static long hidraw_ioctl(struct file
*file
, unsigned int cmd
,
251 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
252 unsigned int minor
= iminor(inode
);
255 void __user
*user_arg
= (void __user
*) arg
;
257 mutex_lock(&minors_lock
);
258 dev
= hidraw_table
[minor
];
265 case HIDIOCGRDESCSIZE
:
266 if (put_user(dev
->hid
->rsize
, (int __user
*)arg
))
274 if (get_user(len
, (int __user
*)arg
))
276 else if (len
> HID_MAX_DESCRIPTOR_SIZE
- 1)
278 else if (copy_to_user(user_arg
+ offsetof(
279 struct hidraw_report_descriptor
,
282 min(dev
->hid
->rsize
, len
)))
288 struct hidraw_devinfo dinfo
;
290 dinfo
.bustype
= dev
->hid
->bus
;
291 dinfo
.vendor
= dev
->hid
->vendor
;
292 dinfo
.product
= dev
->hid
->product
;
293 if (copy_to_user(user_arg
, &dinfo
, sizeof(dinfo
)))
299 struct hid_device
*hid
= dev
->hid
;
300 if (_IOC_TYPE(cmd
) != 'H' || _IOC_DIR(cmd
) != _IOC_READ
) {
305 if (_IOC_NR(cmd
) == _IOC_NR(HIDIOCGRAWNAME(0))) {
311 len
= strlen(hid
->name
) + 1;
312 if (len
> _IOC_SIZE(cmd
))
313 len
= _IOC_SIZE(cmd
);
314 ret
= copy_to_user(user_arg
, hid
->name
, len
) ?
319 if (_IOC_NR(cmd
) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
325 len
= strlen(hid
->phys
) + 1;
326 if (len
> _IOC_SIZE(cmd
))
327 len
= _IOC_SIZE(cmd
);
328 ret
= copy_to_user(user_arg
, hid
->phys
, len
) ?
337 mutex_unlock(&minors_lock
);
341 static const struct file_operations hidraw_ops
= {
342 .owner
= THIS_MODULE
,
344 .write
= hidraw_write
,
347 .release
= hidraw_release
,
348 .unlocked_ioctl
= hidraw_ioctl
,
349 .llseek
= noop_llseek
,
352 void hidraw_report_event(struct hid_device
*hid
, u8
*data
, int len
)
354 struct hidraw
*dev
= hid
->hidraw
;
355 struct hidraw_list
*list
;
357 list_for_each_entry(list
, &dev
->list
, node
) {
358 list
->buffer
[list
->head
].value
= kmemdup(data
, len
, GFP_ATOMIC
);
359 list
->buffer
[list
->head
].len
= len
;
360 list
->head
= (list
->head
+ 1) & (HIDRAW_BUFFER_SIZE
- 1);
361 kill_fasync(&list
->fasync
, SIGIO
, POLL_IN
);
364 wake_up_interruptible(&dev
->wait
);
366 EXPORT_SYMBOL_GPL(hidraw_report_event
);
368 int hidraw_connect(struct hid_device
*hid
)
373 /* we accept any HID device, no matter the applications */
375 dev
= kzalloc(sizeof(struct hidraw
), GFP_KERNEL
);
381 mutex_lock(&minors_lock
);
383 for (minor
= 0; minor
< HIDRAW_MAX_DEVICES
; minor
++) {
384 if (hidraw_table
[minor
])
386 hidraw_table
[minor
] = dev
;
392 mutex_unlock(&minors_lock
);
397 dev
->dev
= device_create(hidraw_class
, &hid
->dev
, MKDEV(hidraw_major
, minor
),
398 NULL
, "%s%d", "hidraw", minor
);
400 if (IS_ERR(dev
->dev
)) {
401 hidraw_table
[minor
] = NULL
;
402 mutex_unlock(&minors_lock
);
403 result
= PTR_ERR(dev
->dev
);
408 mutex_unlock(&minors_lock
);
409 init_waitqueue_head(&dev
->wait
);
410 INIT_LIST_HEAD(&dev
->list
);
422 EXPORT_SYMBOL_GPL(hidraw_connect
);
424 void hidraw_disconnect(struct hid_device
*hid
)
426 struct hidraw
*hidraw
= hid
->hidraw
;
430 mutex_lock(&minors_lock
);
431 hidraw_table
[hidraw
->minor
] = NULL
;
432 mutex_unlock(&minors_lock
);
434 device_destroy(hidraw_class
, MKDEV(hidraw_major
, hidraw
->minor
));
437 hid
->ll_driver
->close(hid
);
438 wake_up_interruptible(&hidraw
->wait
);
443 EXPORT_SYMBOL_GPL(hidraw_disconnect
);
445 int __init
hidraw_init(void)
450 result
= alloc_chrdev_region(&dev_id
, HIDRAW_FIRST_MINOR
,
451 HIDRAW_MAX_DEVICES
, "hidraw");
453 hidraw_major
= MAJOR(dev_id
);
456 printk(KERN_WARNING
"hidraw: can't get major number\n");
461 hidraw_class
= class_create(THIS_MODULE
, "hidraw");
462 if (IS_ERR(hidraw_class
)) {
463 result
= PTR_ERR(hidraw_class
);
464 unregister_chrdev(hidraw_major
, "hidraw");
468 cdev_init(&hidraw_cdev
, &hidraw_ops
);
469 cdev_add(&hidraw_cdev
, dev_id
, HIDRAW_MAX_DEVICES
);
474 void hidraw_exit(void)
476 dev_t dev_id
= MKDEV(hidraw_major
, 0);
478 cdev_del(&hidraw_cdev
);
479 class_destroy(hidraw_class
);
480 unregister_chrdev_region(dev_id
, HIDRAW_MAX_DEVICES
);