xref: /linux/drivers/hid/usbhid/hid-core.c (revision 16cd1c2657762c62a00ac78eecaa25868f7e601b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  USB HID support for Linux
4  *
5  *  Copyright (c) 1999 Andreas Gal
6  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
7  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
8  *  Copyright (c) 2007-2008 Oliver Neukum
9  *  Copyright (c) 2006-2010 Jiri Kosina
10  */
11 
12 /*
13  */
14 
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/init.h>
18 #include <linux/kernel.h>
19 #include <linux/list.h>
20 #include <linux/mm.h>
21 #include <linux/mutex.h>
22 #include <linux/property.h>
23 #include <linux/spinlock.h>
24 #include <linux/unaligned.h>
25 #include <asm/byteorder.h>
26 #include <linux/input.h>
27 #include <linux/wait.h>
28 #include <linux/workqueue.h>
29 #include <linux/string.h>
30 
31 #include <linux/usb.h>
32 
33 #include <linux/hid.h>
34 #include <linux/hiddev.h>
35 #include <linux/hid-debug.h>
36 #include <linux/hidraw.h>
37 #include "usbhid.h"
38 #include "hid-pidff.h"
39 
40 /*
41  * Version Information
42  */
43 
44 #define DRIVER_DESC "USB HID core driver"
45 
46 /*
47  * Module parameters.
48  */
49 
50 static unsigned int hid_mousepoll_interval;
51 module_param_named(mousepoll, hid_mousepoll_interval, uint, 0644);
52 MODULE_PARM_DESC(mousepoll, "Polling interval of mice");
53 
54 static unsigned int hid_jspoll_interval;
55 module_param_named(jspoll, hid_jspoll_interval, uint, 0644);
56 MODULE_PARM_DESC(jspoll, "Polling interval of joysticks");
57 
58 static unsigned int hid_kbpoll_interval;
59 module_param_named(kbpoll, hid_kbpoll_interval, uint, 0644);
60 MODULE_PARM_DESC(kbpoll, "Polling interval of keyboards");
61 
62 static unsigned int ignoreled;
63 module_param_named(ignoreled, ignoreled, uint, 0644);
64 MODULE_PARM_DESC(ignoreled, "Autosuspend with active leds");
65 
66 /* Quirks specified at module load time */
67 static char *quirks_param[MAX_USBHID_BOOT_QUIRKS];
68 module_param_array_named(quirks, quirks_param, charp, NULL, 0444);
69 MODULE_PARM_DESC(quirks, "Add/modify USB HID quirks by specifying "
70 		" quirks=vendorID:productID:quirks"
71 		" where vendorID, productID, and quirks are all in"
72 		" 0x-prefixed hex");
73 /*
74  * Input submission and I/O error handler.
75  */
76 static void hid_io_error(struct hid_device *hid);
77 static int hid_submit_out(struct hid_device *hid);
78 static int hid_submit_ctrl(struct hid_device *hid);
79 static void hid_cancel_delayed_stuff(struct usbhid_device *usbhid);
80 
81 /* Start up the input URB */
hid_start_in(struct hid_device * hid)82 static int hid_start_in(struct hid_device *hid)
83 {
84 	unsigned long flags;
85 	int rc = 0;
86 	struct usbhid_device *usbhid = hid->driver_data;
87 
88 	spin_lock_irqsave(&usbhid->lock, flags);
89 	if (test_bit(HID_IN_POLLING, &usbhid->iofl) &&
90 	    !test_bit(HID_DISCONNECTED, &usbhid->iofl) &&
91 	    !test_bit(HID_SUSPENDED, &usbhid->iofl) &&
92 	    !test_and_set_bit(HID_IN_RUNNING, &usbhid->iofl)) {
93 		rc = usb_submit_urb(usbhid->urbin, GFP_ATOMIC);
94 		if (rc != 0) {
95 			clear_bit(HID_IN_RUNNING, &usbhid->iofl);
96 			if (rc == -ENOSPC)
97 				set_bit(HID_NO_BANDWIDTH, &usbhid->iofl);
98 		} else {
99 			clear_bit(HID_NO_BANDWIDTH, &usbhid->iofl);
100 		}
101 	}
102 	spin_unlock_irqrestore(&usbhid->lock, flags);
103 	return rc;
104 }
105 
106 /* I/O retry timer routine */
hid_retry_timeout(struct timer_list * t)107 static void hid_retry_timeout(struct timer_list *t)
108 {
109 	struct usbhid_device *usbhid = from_timer(usbhid, t, io_retry);
110 	struct hid_device *hid = usbhid->hid;
111 
112 	dev_dbg(&usbhid->intf->dev, "retrying intr urb\n");
113 	if (hid_start_in(hid))
114 		hid_io_error(hid);
115 }
116 
117 /* Workqueue routine to reset the device or clear a halt */
hid_reset(struct work_struct * work)118 static void hid_reset(struct work_struct *work)
119 {
120 	struct usbhid_device *usbhid =
121 		container_of(work, struct usbhid_device, reset_work);
122 	struct hid_device *hid = usbhid->hid;
123 	int rc;
124 
125 	if (test_bit(HID_CLEAR_HALT, &usbhid->iofl)) {
126 		dev_dbg(&usbhid->intf->dev, "clear halt\n");
127 		rc = usb_clear_halt(hid_to_usb_dev(hid), usbhid->urbin->pipe);
128 		clear_bit(HID_CLEAR_HALT, &usbhid->iofl);
129 		if (rc == 0) {
130 			hid_start_in(hid);
131 		} else {
132 			dev_dbg(&usbhid->intf->dev,
133 					"clear-halt failed: %d\n", rc);
134 			set_bit(HID_RESET_PENDING, &usbhid->iofl);
135 		}
136 	}
137 
138 	if (test_bit(HID_RESET_PENDING, &usbhid->iofl)) {
139 		dev_dbg(&usbhid->intf->dev, "resetting device\n");
140 		usb_queue_reset_device(usbhid->intf);
141 	}
142 }
143 
144 /* Main I/O error handler */
hid_io_error(struct hid_device * hid)145 static void hid_io_error(struct hid_device *hid)
146 {
147 	unsigned long flags;
148 	struct usbhid_device *usbhid = hid->driver_data;
149 
150 	spin_lock_irqsave(&usbhid->lock, flags);
151 
152 	/* Stop when disconnected */
153 	if (test_bit(HID_DISCONNECTED, &usbhid->iofl))
154 		goto done;
155 
156 	/* If it has been a while since the last error, we'll assume
157 	 * this a brand new error and reset the retry timeout. */
158 	if (time_after(jiffies, usbhid->stop_retry + HZ/2))
159 		usbhid->retry_delay = 0;
160 
161 	/* When an error occurs, retry at increasing intervals */
162 	if (usbhid->retry_delay == 0) {
163 		usbhid->retry_delay = 13;	/* Then 26, 52, 104, 104, ... */
164 		usbhid->stop_retry = jiffies + msecs_to_jiffies(1000);
165 	} else if (usbhid->retry_delay < 100)
166 		usbhid->retry_delay *= 2;
167 
168 	if (time_after(jiffies, usbhid->stop_retry)) {
169 
170 		/* Retries failed, so do a port reset unless we lack bandwidth*/
171 		if (!test_bit(HID_NO_BANDWIDTH, &usbhid->iofl)
172 		     && !test_and_set_bit(HID_RESET_PENDING, &usbhid->iofl)) {
173 
174 			schedule_work(&usbhid->reset_work);
175 			goto done;
176 		}
177 	}
178 
179 	mod_timer(&usbhid->io_retry,
180 			jiffies + msecs_to_jiffies(usbhid->retry_delay));
181 done:
182 	spin_unlock_irqrestore(&usbhid->lock, flags);
183 }
184 
usbhid_mark_busy(struct usbhid_device * usbhid)185 static void usbhid_mark_busy(struct usbhid_device *usbhid)
186 {
187 	struct usb_interface *intf = usbhid->intf;
188 
189 	usb_mark_last_busy(interface_to_usbdev(intf));
190 }
191 
usbhid_restart_out_queue(struct usbhid_device * usbhid)192 static int usbhid_restart_out_queue(struct usbhid_device *usbhid)
193 {
194 	struct hid_device *hid = usb_get_intfdata(usbhid->intf);
195 	int kicked;
196 	int r;
197 
198 	if (!hid || test_bit(HID_RESET_PENDING, &usbhid->iofl) ||
199 			test_bit(HID_SUSPENDED, &usbhid->iofl))
200 		return 0;
201 
202 	if ((kicked = (usbhid->outhead != usbhid->outtail))) {
203 		hid_dbg(hid, "Kicking head %d tail %d", usbhid->outhead, usbhid->outtail);
204 
205 		/* Try to wake up from autosuspend... */
206 		r = usb_autopm_get_interface_async(usbhid->intf);
207 		if (r < 0)
208 			return r;
209 
210 		/*
211 		 * If still suspended, don't submit.  Submission will
212 		 * occur if/when resume drains the queue.
213 		 */
214 		if (test_bit(HID_SUSPENDED, &usbhid->iofl)) {
215 			usb_autopm_put_interface_no_suspend(usbhid->intf);
216 			return r;
217 		}
218 
219 		/* Asynchronously flush queue. */
220 		set_bit(HID_OUT_RUNNING, &usbhid->iofl);
221 		if (hid_submit_out(hid)) {
222 			clear_bit(HID_OUT_RUNNING, &usbhid->iofl);
223 			usb_autopm_put_interface_async(usbhid->intf);
224 		}
225 		wake_up(&usbhid->wait);
226 	}
227 	return kicked;
228 }
229 
usbhid_restart_ctrl_queue(struct usbhid_device * usbhid)230 static int usbhid_restart_ctrl_queue(struct usbhid_device *usbhid)
231 {
232 	struct hid_device *hid = usb_get_intfdata(usbhid->intf);
233 	int kicked;
234 	int r;
235 
236 	WARN_ON(hid == NULL);
237 	if (!hid || test_bit(HID_RESET_PENDING, &usbhid->iofl) ||
238 			test_bit(HID_SUSPENDED, &usbhid->iofl))
239 		return 0;
240 
241 	if ((kicked = (usbhid->ctrlhead != usbhid->ctrltail))) {
242 		hid_dbg(hid, "Kicking head %d tail %d", usbhid->ctrlhead, usbhid->ctrltail);
243 
244 		/* Try to wake up from autosuspend... */
245 		r = usb_autopm_get_interface_async(usbhid->intf);
246 		if (r < 0)
247 			return r;
248 
249 		/*
250 		 * If still suspended, don't submit.  Submission will
251 		 * occur if/when resume drains the queue.
252 		 */
253 		if (test_bit(HID_SUSPENDED, &usbhid->iofl)) {
254 			usb_autopm_put_interface_no_suspend(usbhid->intf);
255 			return r;
256 		}
257 
258 		/* Asynchronously flush queue. */
259 		set_bit(HID_CTRL_RUNNING, &usbhid->iofl);
260 		if (hid_submit_ctrl(hid)) {
261 			clear_bit(HID_CTRL_RUNNING, &usbhid->iofl);
262 			usb_autopm_put_interface_async(usbhid->intf);
263 		}
264 		wake_up(&usbhid->wait);
265 	}
266 	return kicked;
267 }
268 
269 /*
270  * Input interrupt completion handler.
271  */
272 
hid_irq_in(struct urb * urb)273 static void hid_irq_in(struct urb *urb)
274 {
275 	struct hid_device	*hid = urb->context;
276 	struct usbhid_device	*usbhid = hid->driver_data;
277 	int			status;
278 
279 	switch (urb->status) {
280 	case 0:			/* success */
281 		usbhid->retry_delay = 0;
282 		if (!test_bit(HID_OPENED, &usbhid->iofl))
283 			break;
284 		usbhid_mark_busy(usbhid);
285 		if (!test_bit(HID_RESUME_RUNNING, &usbhid->iofl)) {
286 			hid_input_report(urb->context, HID_INPUT_REPORT,
287 					 urb->transfer_buffer,
288 					 urb->actual_length, 1);
289 			/*
290 			 * autosuspend refused while keys are pressed
291 			 * because most keyboards don't wake up when
292 			 * a key is released
293 			 */
294 			if (hid_check_keys_pressed(hid))
295 				set_bit(HID_KEYS_PRESSED, &usbhid->iofl);
296 			else
297 				clear_bit(HID_KEYS_PRESSED, &usbhid->iofl);
298 		}
299 		break;
300 	case -EPIPE:		/* stall */
301 		usbhid_mark_busy(usbhid);
302 		clear_bit(HID_IN_RUNNING, &usbhid->iofl);
303 		set_bit(HID_CLEAR_HALT, &usbhid->iofl);
304 		schedule_work(&usbhid->reset_work);
305 		return;
306 	case -ECONNRESET:	/* unlink */
307 	case -ENOENT:
308 	case -ESHUTDOWN:	/* unplug */
309 		clear_bit(HID_IN_RUNNING, &usbhid->iofl);
310 		return;
311 	case -EILSEQ:		/* protocol error or unplug */
312 	case -EPROTO:		/* protocol error or unplug */
313 	case -ETIME:		/* protocol error or unplug */
314 	case -ETIMEDOUT:	/* Should never happen, but... */
315 		usbhid_mark_busy(usbhid);
316 		clear_bit(HID_IN_RUNNING, &usbhid->iofl);
317 		hid_io_error(hid);
318 		return;
319 	default:		/* error */
320 		hid_warn(urb->dev, "input irq status %d received\n",
321 			 urb->status);
322 	}
323 
324 	status = usb_submit_urb(urb, GFP_ATOMIC);
325 	if (status) {
326 		clear_bit(HID_IN_RUNNING, &usbhid->iofl);
327 		if (status != -EPERM) {
328 			hid_err(hid, "can't resubmit intr, %s-%s/input%d, status %d\n",
329 				hid_to_usb_dev(hid)->bus->bus_name,
330 				hid_to_usb_dev(hid)->devpath,
331 				usbhid->ifnum, status);
332 			hid_io_error(hid);
333 		}
334 	}
335 }
336 
hid_submit_out(struct hid_device * hid)337 static int hid_submit_out(struct hid_device *hid)
338 {
339 	struct hid_report *report;
340 	char *raw_report;
341 	struct usbhid_device *usbhid = hid->driver_data;
342 	int r;
343 
344 	report = usbhid->out[usbhid->outtail].report;
345 	raw_report = usbhid->out[usbhid->outtail].raw_report;
346 
347 	usbhid->urbout->transfer_buffer_length = hid_report_len(report);
348 	usbhid->urbout->dev = hid_to_usb_dev(hid);
349 	if (raw_report) {
350 		memcpy(usbhid->outbuf, raw_report,
351 				usbhid->urbout->transfer_buffer_length);
352 		kfree(raw_report);
353 		usbhid->out[usbhid->outtail].raw_report = NULL;
354 	}
355 
356 	dbg_hid("submitting out urb\n");
357 
358 	r = usb_submit_urb(usbhid->urbout, GFP_ATOMIC);
359 	if (r < 0) {
360 		hid_err(hid, "usb_submit_urb(out) failed: %d\n", r);
361 		return r;
362 	}
363 	usbhid->last_out = jiffies;
364 	return 0;
365 }
366 
hid_submit_ctrl(struct hid_device * hid)367 static int hid_submit_ctrl(struct hid_device *hid)
368 {
369 	struct hid_report *report;
370 	unsigned char dir;
371 	char *raw_report;
372 	int len, r;
373 	struct usbhid_device *usbhid = hid->driver_data;
374 
375 	report = usbhid->ctrl[usbhid->ctrltail].report;
376 	raw_report = usbhid->ctrl[usbhid->ctrltail].raw_report;
377 	dir = usbhid->ctrl[usbhid->ctrltail].dir;
378 
379 	len = hid_report_len(report);
380 	if (dir == USB_DIR_OUT) {
381 		usbhid->urbctrl->pipe = usb_sndctrlpipe(hid_to_usb_dev(hid), 0);
382 		if (raw_report) {
383 			memcpy(usbhid->ctrlbuf, raw_report, len);
384 			kfree(raw_report);
385 			usbhid->ctrl[usbhid->ctrltail].raw_report = NULL;
386 		}
387 	} else {
388 		int maxpacket;
389 
390 		usbhid->urbctrl->pipe = usb_rcvctrlpipe(hid_to_usb_dev(hid), 0);
391 		maxpacket = usb_maxpacket(hid_to_usb_dev(hid),
392 					  usbhid->urbctrl->pipe);
393 		len += (len == 0);	/* Don't allow 0-length reports */
394 		len = round_up(len, maxpacket);
395 		if (len > usbhid->bufsize)
396 			len = usbhid->bufsize;
397 	}
398 	usbhid->urbctrl->transfer_buffer_length = len;
399 	usbhid->urbctrl->dev = hid_to_usb_dev(hid);
400 
401 	usbhid->cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE | dir;
402 	usbhid->cr->bRequest = (dir == USB_DIR_OUT) ? HID_REQ_SET_REPORT :
403 						      HID_REQ_GET_REPORT;
404 	usbhid->cr->wValue = cpu_to_le16(((report->type + 1) << 8) |
405 					 report->id);
406 	usbhid->cr->wIndex = cpu_to_le16(usbhid->ifnum);
407 	usbhid->cr->wLength = cpu_to_le16(len);
408 
409 	dbg_hid("submitting ctrl urb: %s wValue=0x%04x wIndex=0x%04x wLength=%u\n",
410 		usbhid->cr->bRequest == HID_REQ_SET_REPORT ? "Set_Report" :
411 							     "Get_Report",
412 		usbhid->cr->wValue, usbhid->cr->wIndex, usbhid->cr->wLength);
413 
414 	r = usb_submit_urb(usbhid->urbctrl, GFP_ATOMIC);
415 	if (r < 0) {
416 		hid_err(hid, "usb_submit_urb(ctrl) failed: %d\n", r);
417 		return r;
418 	}
419 	usbhid->last_ctrl = jiffies;
420 	return 0;
421 }
422 
423 /*
424  * Output interrupt completion handler.
425  */
426 
hid_irq_out(struct urb * urb)427 static void hid_irq_out(struct urb *urb)
428 {
429 	struct hid_device *hid = urb->context;
430 	struct usbhid_device *usbhid = hid->driver_data;
431 	unsigned long flags;
432 	int unplug = 0;
433 
434 	switch (urb->status) {
435 	case 0:			/* success */
436 		break;
437 	case -ESHUTDOWN:	/* unplug */
438 		unplug = 1;
439 		break;
440 	case -EILSEQ:		/* protocol error or unplug */
441 	case -EPROTO:		/* protocol error or unplug */
442 	case -ECONNRESET:	/* unlink */
443 	case -ENOENT:
444 		break;
445 	default:		/* error */
446 		hid_warn(urb->dev, "output irq status %d received\n",
447 			 urb->status);
448 	}
449 
450 	spin_lock_irqsave(&usbhid->lock, flags);
451 
452 	if (unplug) {
453 		usbhid->outtail = usbhid->outhead;
454 	} else {
455 		usbhid->outtail = (usbhid->outtail + 1) & (HID_OUTPUT_FIFO_SIZE - 1);
456 
457 		if (usbhid->outhead != usbhid->outtail &&
458 				hid_submit_out(hid) == 0) {
459 			/* Successfully submitted next urb in queue */
460 			spin_unlock_irqrestore(&usbhid->lock, flags);
461 			return;
462 		}
463 	}
464 
465 	clear_bit(HID_OUT_RUNNING, &usbhid->iofl);
466 	spin_unlock_irqrestore(&usbhid->lock, flags);
467 	usb_autopm_put_interface_async(usbhid->intf);
468 	wake_up(&usbhid->wait);
469 }
470 
471 /*
472  * Control pipe completion handler.
473  */
474 
hid_ctrl(struct urb * urb)475 static void hid_ctrl(struct urb *urb)
476 {
477 	struct hid_device *hid = urb->context;
478 	struct usbhid_device *usbhid = hid->driver_data;
479 	unsigned long flags;
480 	int unplug = 0, status = urb->status;
481 
482 	switch (status) {
483 	case 0:			/* success */
484 		if (usbhid->ctrl[usbhid->ctrltail].dir == USB_DIR_IN)
485 			hid_input_report(urb->context,
486 				usbhid->ctrl[usbhid->ctrltail].report->type,
487 				urb->transfer_buffer, urb->actual_length, 0);
488 		break;
489 	case -ESHUTDOWN:	/* unplug */
490 		unplug = 1;
491 		break;
492 	case -EILSEQ:		/* protocol error or unplug */
493 	case -EPROTO:		/* protocol error or unplug */
494 	case -ECONNRESET:	/* unlink */
495 	case -ENOENT:
496 	case -EPIPE:		/* report not available */
497 		break;
498 	default:		/* error */
499 		hid_warn(urb->dev, "ctrl urb status %d received\n", status);
500 	}
501 
502 	spin_lock_irqsave(&usbhid->lock, flags);
503 
504 	if (unplug) {
505 		usbhid->ctrltail = usbhid->ctrlhead;
506 	} else if (usbhid->ctrlhead != usbhid->ctrltail) {
507 		usbhid->ctrltail = (usbhid->ctrltail + 1) & (HID_CONTROL_FIFO_SIZE - 1);
508 
509 		if (usbhid->ctrlhead != usbhid->ctrltail &&
510 				hid_submit_ctrl(hid) == 0) {
511 			/* Successfully submitted next urb in queue */
512 			spin_unlock_irqrestore(&usbhid->lock, flags);
513 			return;
514 		}
515 	}
516 
517 	clear_bit(HID_CTRL_RUNNING, &usbhid->iofl);
518 	spin_unlock_irqrestore(&usbhid->lock, flags);
519 	usb_autopm_put_interface_async(usbhid->intf);
520 	wake_up(&usbhid->wait);
521 }
522 
__usbhid_submit_report(struct hid_device * hid,struct hid_report * report,unsigned char dir)523 static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *report,
524 				   unsigned char dir)
525 {
526 	int head;
527 	struct usbhid_device *usbhid = hid->driver_data;
528 
529 	if (((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN) ||
530 		test_bit(HID_DISCONNECTED, &usbhid->iofl))
531 		return;
532 
533 	if (usbhid->urbout && dir == USB_DIR_OUT && report->type == HID_OUTPUT_REPORT) {
534 		if ((head = (usbhid->outhead + 1) & (HID_OUTPUT_FIFO_SIZE - 1)) == usbhid->outtail) {
535 			hid_warn(hid, "output queue full\n");
536 			return;
537 		}
538 
539 		usbhid->out[usbhid->outhead].raw_report = hid_alloc_report_buf(report, GFP_ATOMIC);
540 		if (!usbhid->out[usbhid->outhead].raw_report) {
541 			hid_warn(hid, "output queueing failed\n");
542 			return;
543 		}
544 		hid_output_report(report, usbhid->out[usbhid->outhead].raw_report);
545 		usbhid->out[usbhid->outhead].report = report;
546 		usbhid->outhead = head;
547 
548 		/* If the queue isn't running, restart it */
549 		if (!test_bit(HID_OUT_RUNNING, &usbhid->iofl)) {
550 			usbhid_restart_out_queue(usbhid);
551 
552 		/* Otherwise see if an earlier request has timed out */
553 		} else if (time_after(jiffies, usbhid->last_out + HZ * 5)) {
554 
555 			/* Prevent autosuspend following the unlink */
556 			usb_autopm_get_interface_no_resume(usbhid->intf);
557 
558 			/*
559 			 * Prevent resubmission in case the URB completes
560 			 * before we can unlink it.  We don't want to cancel
561 			 * the wrong transfer!
562 			 */
563 			usb_block_urb(usbhid->urbout);
564 
565 			/* Drop lock to avoid deadlock if the callback runs */
566 			spin_unlock(&usbhid->lock);
567 
568 			usb_unlink_urb(usbhid->urbout);
569 			spin_lock(&usbhid->lock);
570 			usb_unblock_urb(usbhid->urbout);
571 
572 			/* Unlink might have stopped the queue */
573 			if (!test_bit(HID_OUT_RUNNING, &usbhid->iofl))
574 				usbhid_restart_out_queue(usbhid);
575 
576 			/* Now we can allow autosuspend again */
577 			usb_autopm_put_interface_async(usbhid->intf);
578 		}
579 		return;
580 	}
581 
582 	if ((head = (usbhid->ctrlhead + 1) & (HID_CONTROL_FIFO_SIZE - 1)) == usbhid->ctrltail) {
583 		hid_warn(hid, "control queue full\n");
584 		return;
585 	}
586 
587 	if (dir == USB_DIR_OUT) {
588 		usbhid->ctrl[usbhid->ctrlhead].raw_report = hid_alloc_report_buf(report, GFP_ATOMIC);
589 		if (!usbhid->ctrl[usbhid->ctrlhead].raw_report) {
590 			hid_warn(hid, "control queueing failed\n");
591 			return;
592 		}
593 		hid_output_report(report, usbhid->ctrl[usbhid->ctrlhead].raw_report);
594 	}
595 	usbhid->ctrl[usbhid->ctrlhead].report = report;
596 	usbhid->ctrl[usbhid->ctrlhead].dir = dir;
597 	usbhid->ctrlhead = head;
598 
599 	/* If the queue isn't running, restart it */
600 	if (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl)) {
601 		usbhid_restart_ctrl_queue(usbhid);
602 
603 	/* Otherwise see if an earlier request has timed out */
604 	} else if (time_after(jiffies, usbhid->last_ctrl + HZ * 5)) {
605 
606 		/* Prevent autosuspend following the unlink */
607 		usb_autopm_get_interface_no_resume(usbhid->intf);
608 
609 		/*
610 		 * Prevent resubmission in case the URB completes
611 		 * before we can unlink it.  We don't want to cancel
612 		 * the wrong transfer!
613 		 */
614 		usb_block_urb(usbhid->urbctrl);
615 
616 		/* Drop lock to avoid deadlock if the callback runs */
617 		spin_unlock(&usbhid->lock);
618 
619 		usb_unlink_urb(usbhid->urbctrl);
620 		spin_lock(&usbhid->lock);
621 		usb_unblock_urb(usbhid->urbctrl);
622 
623 		/* Unlink might have stopped the queue */
624 		if (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl))
625 			usbhid_restart_ctrl_queue(usbhid);
626 
627 		/* Now we can allow autosuspend again */
628 		usb_autopm_put_interface_async(usbhid->intf);
629 	}
630 }
631 
usbhid_submit_report(struct hid_device * hid,struct hid_report * report,unsigned char dir)632 static void usbhid_submit_report(struct hid_device *hid, struct hid_report *report, unsigned char dir)
633 {
634 	struct usbhid_device *usbhid = hid->driver_data;
635 	unsigned long flags;
636 
637 	spin_lock_irqsave(&usbhid->lock, flags);
638 	__usbhid_submit_report(hid, report, dir);
639 	spin_unlock_irqrestore(&usbhid->lock, flags);
640 }
641 
usbhid_wait_io(struct hid_device * hid)642 static int usbhid_wait_io(struct hid_device *hid)
643 {
644 	struct usbhid_device *usbhid = hid->driver_data;
645 
646 	if (!wait_event_timeout(usbhid->wait,
647 				(!test_bit(HID_CTRL_RUNNING, &usbhid->iofl) &&
648 				!test_bit(HID_OUT_RUNNING, &usbhid->iofl)),
649 					10*HZ)) {
650 		dbg_hid("timeout waiting for ctrl or out queue to clear\n");
651 		return -1;
652 	}
653 
654 	return 0;
655 }
656 
hid_set_idle(struct usb_device * dev,int ifnum,int report,int idle)657 static int hid_set_idle(struct usb_device *dev, int ifnum, int report, int idle)
658 {
659 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
660 		HID_REQ_SET_IDLE, USB_TYPE_CLASS | USB_RECIP_INTERFACE, (idle << 8) | report,
661 		ifnum, NULL, 0, USB_CTRL_SET_TIMEOUT);
662 }
663 
hid_get_class_descriptor(struct usb_device * dev,int ifnum,unsigned char type,void * buf,int size)664 static int hid_get_class_descriptor(struct usb_device *dev, int ifnum,
665 		unsigned char type, void *buf, int size)
666 {
667 	int result, retries = 4;
668 
669 	memset(buf, 0, size);
670 
671 	do {
672 		result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
673 				USB_REQ_GET_DESCRIPTOR, USB_RECIP_INTERFACE | USB_DIR_IN,
674 				(type << 8), ifnum, buf, size, USB_CTRL_GET_TIMEOUT);
675 		retries--;
676 	} while (result < size && retries);
677 	return result;
678 }
679 
usbhid_open(struct hid_device * hid)680 static int usbhid_open(struct hid_device *hid)
681 {
682 	struct usbhid_device *usbhid = hid->driver_data;
683 	int res;
684 
685 	mutex_lock(&usbhid->mutex);
686 
687 	set_bit(HID_OPENED, &usbhid->iofl);
688 
689 	if (hid->quirks & HID_QUIRK_ALWAYS_POLL) {
690 		res = 0;
691 		goto Done;
692 	}
693 
694 	res = usb_autopm_get_interface(usbhid->intf);
695 	/* the device must be awake to reliably request remote wakeup */
696 	if (res < 0) {
697 		clear_bit(HID_OPENED, &usbhid->iofl);
698 		res = -EIO;
699 		goto Done;
700 	}
701 
702 	usbhid->intf->needs_remote_wakeup = 1;
703 
704 	set_bit(HID_RESUME_RUNNING, &usbhid->iofl);
705 	set_bit(HID_IN_POLLING, &usbhid->iofl);
706 
707 	res = hid_start_in(hid);
708 	if (res) {
709 		if (res != -ENOSPC) {
710 			hid_io_error(hid);
711 			res = 0;
712 		} else {
713 			/* no use opening if resources are insufficient */
714 			res = -EBUSY;
715 			clear_bit(HID_OPENED, &usbhid->iofl);
716 			clear_bit(HID_IN_POLLING, &usbhid->iofl);
717 			usbhid->intf->needs_remote_wakeup = 0;
718 		}
719 	}
720 
721 	usb_autopm_put_interface(usbhid->intf);
722 
723 	/*
724 	 * In case events are generated while nobody was listening,
725 	 * some are released when the device is re-opened.
726 	 * Wait 50 msec for the queue to empty before allowing events
727 	 * to go through hid.
728 	 */
729 	if (res == 0)
730 		msleep(50);
731 
732 	clear_bit(HID_RESUME_RUNNING, &usbhid->iofl);
733 
734  Done:
735 	mutex_unlock(&usbhid->mutex);
736 	return res;
737 }
738 
usbhid_close(struct hid_device * hid)739 static void usbhid_close(struct hid_device *hid)
740 {
741 	struct usbhid_device *usbhid = hid->driver_data;
742 
743 	mutex_lock(&usbhid->mutex);
744 
745 	/*
746 	 * Make sure we don't restart data acquisition due to
747 	 * a resumption we no longer care about by avoiding racing
748 	 * with hid_start_in().
749 	 */
750 	spin_lock_irq(&usbhid->lock);
751 	clear_bit(HID_OPENED, &usbhid->iofl);
752 	if (!(hid->quirks & HID_QUIRK_ALWAYS_POLL))
753 		clear_bit(HID_IN_POLLING, &usbhid->iofl);
754 	spin_unlock_irq(&usbhid->lock);
755 
756 	if (!(hid->quirks & HID_QUIRK_ALWAYS_POLL)) {
757 		hid_cancel_delayed_stuff(usbhid);
758 		usb_kill_urb(usbhid->urbin);
759 		usbhid->intf->needs_remote_wakeup = 0;
760 	}
761 
762 	mutex_unlock(&usbhid->mutex);
763 }
764 
765 /*
766  * Initialize all reports
767  */
768 
usbhid_init_reports(struct hid_device * hid)769 void usbhid_init_reports(struct hid_device *hid)
770 {
771 	struct hid_report *report;
772 	struct usbhid_device *usbhid = hid->driver_data;
773 	struct hid_report_enum *report_enum;
774 	int err, ret;
775 
776 	report_enum = &hid->report_enum[HID_INPUT_REPORT];
777 	list_for_each_entry(report, &report_enum->report_list, list)
778 		usbhid_submit_report(hid, report, USB_DIR_IN);
779 
780 	report_enum = &hid->report_enum[HID_FEATURE_REPORT];
781 	list_for_each_entry(report, &report_enum->report_list, list)
782 		usbhid_submit_report(hid, report, USB_DIR_IN);
783 
784 	err = 0;
785 	ret = usbhid_wait_io(hid);
786 	while (ret) {
787 		err |= ret;
788 		if (test_bit(HID_CTRL_RUNNING, &usbhid->iofl))
789 			usb_kill_urb(usbhid->urbctrl);
790 		if (test_bit(HID_OUT_RUNNING, &usbhid->iofl))
791 			usb_kill_urb(usbhid->urbout);
792 		ret = usbhid_wait_io(hid);
793 	}
794 
795 	if (err)
796 		hid_warn(hid, "timeout initializing reports\n");
797 }
798 
799 /*
800  * Reset LEDs which BIOS might have left on. For now, just NumLock (0x01).
801  */
hid_find_field_early(struct hid_device * hid,unsigned int page,unsigned int hid_code,struct hid_field ** pfield)802 static int hid_find_field_early(struct hid_device *hid, unsigned int page,
803     unsigned int hid_code, struct hid_field **pfield)
804 {
805 	struct hid_report *report;
806 	struct hid_field *field;
807 	struct hid_usage *usage;
808 	int i, j;
809 
810 	list_for_each_entry(report, &hid->report_enum[HID_OUTPUT_REPORT].report_list, list) {
811 		for (i = 0; i < report->maxfield; i++) {
812 			field = report->field[i];
813 			for (j = 0; j < field->maxusage; j++) {
814 				usage = &field->usage[j];
815 				if ((usage->hid & HID_USAGE_PAGE) == page &&
816 				    (usage->hid & 0xFFFF) == hid_code) {
817 					*pfield = field;
818 					return j;
819 				}
820 			}
821 		}
822 	}
823 	return -1;
824 }
825 
usbhid_set_leds(struct hid_device * hid)826 static void usbhid_set_leds(struct hid_device *hid)
827 {
828 	struct hid_field *field;
829 	int offset;
830 
831 	if ((offset = hid_find_field_early(hid, HID_UP_LED, 0x01, &field)) != -1) {
832 		hid_set_field(field, offset, 0);
833 		usbhid_submit_report(hid, field->report, USB_DIR_OUT);
834 	}
835 }
836 
837 /*
838  * Traverse the supplied list of reports and find the longest
839  */
hid_find_max_report(struct hid_device * hid,unsigned int type,unsigned int * max)840 static void hid_find_max_report(struct hid_device *hid, unsigned int type,
841 		unsigned int *max)
842 {
843 	struct hid_report *report;
844 	unsigned int size;
845 
846 	list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
847 		size = ((report->size - 1) >> 3) + 1 + hid->report_enum[type].numbered;
848 		if (*max < size)
849 			*max = size;
850 	}
851 }
852 
hid_alloc_buffers(struct usb_device * dev,struct hid_device * hid)853 static int hid_alloc_buffers(struct usb_device *dev, struct hid_device *hid)
854 {
855 	struct usbhid_device *usbhid = hid->driver_data;
856 
857 	usbhid->inbuf = usb_alloc_coherent(dev, usbhid->bufsize, GFP_KERNEL,
858 			&usbhid->inbuf_dma);
859 	usbhid->outbuf = usb_alloc_coherent(dev, usbhid->bufsize, GFP_KERNEL,
860 			&usbhid->outbuf_dma);
861 	usbhid->cr = kmalloc(sizeof(*usbhid->cr), GFP_KERNEL);
862 	usbhid->ctrlbuf = usb_alloc_coherent(dev, usbhid->bufsize, GFP_KERNEL,
863 			&usbhid->ctrlbuf_dma);
864 	if (!usbhid->inbuf || !usbhid->outbuf || !usbhid->cr ||
865 			!usbhid->ctrlbuf)
866 		return -1;
867 
868 	return 0;
869 }
870 
usbhid_get_raw_report(struct hid_device * hid,unsigned char report_number,__u8 * buf,size_t count,unsigned char report_type)871 static int usbhid_get_raw_report(struct hid_device *hid,
872 		unsigned char report_number, __u8 *buf, size_t count,
873 		unsigned char report_type)
874 {
875 	struct usbhid_device *usbhid = hid->driver_data;
876 	struct usb_device *dev = hid_to_usb_dev(hid);
877 	struct usb_interface *intf = usbhid->intf;
878 	struct usb_host_interface *interface = intf->cur_altsetting;
879 	int skipped_report_id = 0;
880 	int ret;
881 
882 	/* Byte 0 is the report number. Report data starts at byte 1.*/
883 	buf[0] = report_number;
884 	if (report_number == 0x0) {
885 		/* Offset the return buffer by 1, so that the report ID
886 		   will remain in byte 0. */
887 		buf++;
888 		count--;
889 		skipped_report_id = 1;
890 	}
891 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
892 		HID_REQ_GET_REPORT,
893 		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
894 		((report_type + 1) << 8) | report_number,
895 		interface->desc.bInterfaceNumber, buf, count,
896 		USB_CTRL_SET_TIMEOUT);
897 
898 	/* count also the report id */
899 	if (ret > 0 && skipped_report_id)
900 		ret++;
901 
902 	return ret;
903 }
904 
usbhid_set_raw_report(struct hid_device * hid,unsigned int reportnum,__u8 * buf,size_t count,unsigned char rtype)905 static int usbhid_set_raw_report(struct hid_device *hid, unsigned int reportnum,
906 				 __u8 *buf, size_t count, unsigned char rtype)
907 {
908 	struct usbhid_device *usbhid = hid->driver_data;
909 	struct usb_device *dev = hid_to_usb_dev(hid);
910 	struct usb_interface *intf = usbhid->intf;
911 	struct usb_host_interface *interface = intf->cur_altsetting;
912 	int ret, skipped_report_id = 0;
913 
914 	/* Byte 0 is the report number. Report data starts at byte 1.*/
915 	if ((rtype == HID_OUTPUT_REPORT) &&
916 	    (hid->quirks & HID_QUIRK_SKIP_OUTPUT_REPORT_ID))
917 		buf[0] = 0;
918 	else
919 		buf[0] = reportnum;
920 
921 	if (buf[0] == 0x0) {
922 		/* Don't send the Report ID */
923 		buf++;
924 		count--;
925 		skipped_report_id = 1;
926 	}
927 
928 	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
929 			HID_REQ_SET_REPORT,
930 			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
931 			((rtype + 1) << 8) | reportnum,
932 			interface->desc.bInterfaceNumber, buf, count,
933 			USB_CTRL_SET_TIMEOUT);
934 	/* count also the report id, if this was a numbered report. */
935 	if (ret > 0 && skipped_report_id)
936 		ret++;
937 
938 	return ret;
939 }
940 
usbhid_output_report(struct hid_device * hid,__u8 * buf,size_t count)941 static int usbhid_output_report(struct hid_device *hid, __u8 *buf, size_t count)
942 {
943 	struct usbhid_device *usbhid = hid->driver_data;
944 	struct usb_device *dev = hid_to_usb_dev(hid);
945 	int actual_length, skipped_report_id = 0, ret;
946 
947 	if (!usbhid->urbout)
948 		return -ENOSYS;
949 
950 	if (buf[0] == 0x0) {
951 		/* Don't send the Report ID */
952 		buf++;
953 		count--;
954 		skipped_report_id = 1;
955 	}
956 
957 	ret = usb_interrupt_msg(dev, usbhid->urbout->pipe,
958 				buf, count, &actual_length,
959 				USB_CTRL_SET_TIMEOUT);
960 	/* return the number of bytes transferred */
961 	if (ret == 0) {
962 		ret = actual_length;
963 		/* count also the report id */
964 		if (skipped_report_id)
965 			ret++;
966 	}
967 
968 	return ret;
969 }
970 
hid_free_buffers(struct usb_device * dev,struct hid_device * hid)971 static void hid_free_buffers(struct usb_device *dev, struct hid_device *hid)
972 {
973 	struct usbhid_device *usbhid = hid->driver_data;
974 
975 	usb_free_coherent(dev, usbhid->bufsize, usbhid->inbuf, usbhid->inbuf_dma);
976 	usb_free_coherent(dev, usbhid->bufsize, usbhid->outbuf, usbhid->outbuf_dma);
977 	kfree(usbhid->cr);
978 	usb_free_coherent(dev, usbhid->bufsize, usbhid->ctrlbuf, usbhid->ctrlbuf_dma);
979 }
980 
usbhid_parse(struct hid_device * hid)981 static int usbhid_parse(struct hid_device *hid)
982 {
983 	struct usb_interface *intf = to_usb_interface(hid->dev.parent);
984 	struct usb_host_interface *interface = intf->cur_altsetting;
985 	struct usb_device *dev = interface_to_usbdev (intf);
986 	struct hid_descriptor *hdesc;
987 	u32 quirks = 0;
988 	unsigned int rsize = 0;
989 	char *rdesc;
990 	int ret, n;
991 	int num_descriptors;
992 	size_t offset = offsetof(struct hid_descriptor, desc);
993 
994 	quirks = hid_lookup_quirk(hid);
995 
996 	if (quirks & HID_QUIRK_IGNORE)
997 		return -ENODEV;
998 
999 	/* Many keyboards and mice don't like to be polled for reports,
1000 	 * so we will always set the HID_QUIRK_NOGET flag for them. */
1001 	if (interface->desc.bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {
1002 		if (interface->desc.bInterfaceProtocol == USB_INTERFACE_PROTOCOL_KEYBOARD ||
1003 			interface->desc.bInterfaceProtocol == USB_INTERFACE_PROTOCOL_MOUSE)
1004 				quirks |= HID_QUIRK_NOGET;
1005 	}
1006 
1007 	if (usb_get_extra_descriptor(interface, HID_DT_HID, &hdesc) &&
1008 	    (!interface->desc.bNumEndpoints ||
1009 	     usb_get_extra_descriptor(&interface->endpoint[0], HID_DT_HID, &hdesc))) {
1010 		dbg_hid("class descriptor not present\n");
1011 		return -ENODEV;
1012 	}
1013 
1014 	if (hdesc->bLength < sizeof(struct hid_descriptor)) {
1015 		dbg_hid("hid descriptor is too short\n");
1016 		return -EINVAL;
1017 	}
1018 
1019 	hid->version = le16_to_cpu(hdesc->bcdHID);
1020 	hid->country = hdesc->bCountryCode;
1021 
1022 	num_descriptors = min_t(int, hdesc->bNumDescriptors,
1023 	       (hdesc->bLength - offset) / sizeof(struct hid_class_descriptor));
1024 
1025 	for (n = 0; n < num_descriptors; n++)
1026 		if (hdesc->desc[n].bDescriptorType == HID_DT_REPORT)
1027 			rsize = le16_to_cpu(hdesc->desc[n].wDescriptorLength);
1028 
1029 	if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
1030 		dbg_hid("weird size of report descriptor (%u)\n", rsize);
1031 		return -EINVAL;
1032 	}
1033 
1034 	rdesc = kmalloc(rsize, GFP_KERNEL);
1035 	if (!rdesc)
1036 		return -ENOMEM;
1037 
1038 	hid_set_idle(dev, interface->desc.bInterfaceNumber, 0, 0);
1039 
1040 	ret = hid_get_class_descriptor(dev, interface->desc.bInterfaceNumber,
1041 			HID_DT_REPORT, rdesc, rsize);
1042 	if (ret < 0) {
1043 		dbg_hid("reading report descriptor failed\n");
1044 		kfree(rdesc);
1045 		goto err;
1046 	}
1047 
1048 	ret = hid_parse_report(hid, rdesc, rsize);
1049 	kfree(rdesc);
1050 	if (ret) {
1051 		dbg_hid("parsing report descriptor failed\n");
1052 		goto err;
1053 	}
1054 
1055 	hid->quirks |= quirks;
1056 
1057 	return 0;
1058 err:
1059 	return ret;
1060 }
1061 
usbhid_start(struct hid_device * hid)1062 static int usbhid_start(struct hid_device *hid)
1063 {
1064 	struct usb_interface *intf = to_usb_interface(hid->dev.parent);
1065 	struct usb_host_interface *interface = intf->cur_altsetting;
1066 	struct usb_device *dev = interface_to_usbdev(intf);
1067 	struct usbhid_device *usbhid = hid->driver_data;
1068 	unsigned int n, insize = 0;
1069 	int ret;
1070 
1071 	mutex_lock(&usbhid->mutex);
1072 
1073 	clear_bit(HID_DISCONNECTED, &usbhid->iofl);
1074 
1075 	usbhid->bufsize = HID_MIN_BUFFER_SIZE;
1076 	hid_find_max_report(hid, HID_INPUT_REPORT, &usbhid->bufsize);
1077 	hid_find_max_report(hid, HID_OUTPUT_REPORT, &usbhid->bufsize);
1078 	hid_find_max_report(hid, HID_FEATURE_REPORT, &usbhid->bufsize);
1079 
1080 	if (usbhid->bufsize > HID_MAX_BUFFER_SIZE)
1081 		usbhid->bufsize = HID_MAX_BUFFER_SIZE;
1082 
1083 	hid_find_max_report(hid, HID_INPUT_REPORT, &insize);
1084 
1085 	if (insize > HID_MAX_BUFFER_SIZE)
1086 		insize = HID_MAX_BUFFER_SIZE;
1087 
1088 	if (hid_alloc_buffers(dev, hid)) {
1089 		ret = -ENOMEM;
1090 		goto fail;
1091 	}
1092 
1093 	for (n = 0; n < interface->desc.bNumEndpoints; n++) {
1094 		struct usb_endpoint_descriptor *endpoint;
1095 		int pipe;
1096 		int interval;
1097 
1098 		endpoint = &interface->endpoint[n].desc;
1099 		if (!usb_endpoint_xfer_int(endpoint))
1100 			continue;
1101 
1102 		interval = endpoint->bInterval;
1103 
1104 		/* Some vendors give fullspeed interval on highspeed devices */
1105 		if (hid->quirks & HID_QUIRK_FULLSPEED_INTERVAL &&
1106 		    dev->speed == USB_SPEED_HIGH) {
1107 			interval = fls(endpoint->bInterval*8);
1108 			pr_info("%s: Fixing fullspeed to highspeed interval: %d -> %d\n",
1109 				hid->name, endpoint->bInterval, interval);
1110 		}
1111 
1112 		/* Change the polling interval of mice, joysticks
1113 		 * and keyboards.
1114 		 */
1115 		switch (hid->collection->usage) {
1116 		case HID_GD_MOUSE:
1117 			if (hid_mousepoll_interval > 0)
1118 				interval = hid_mousepoll_interval;
1119 			break;
1120 		case HID_GD_JOYSTICK:
1121 			if (hid_jspoll_interval > 0)
1122 				interval = hid_jspoll_interval;
1123 			break;
1124 		case HID_GD_KEYBOARD:
1125 			if (hid_kbpoll_interval > 0)
1126 				interval = hid_kbpoll_interval;
1127 			break;
1128 		}
1129 
1130 		ret = -ENOMEM;
1131 		if (usb_endpoint_dir_in(endpoint)) {
1132 			if (usbhid->urbin)
1133 				continue;
1134 			if (!(usbhid->urbin = usb_alloc_urb(0, GFP_KERNEL)))
1135 				goto fail;
1136 			pipe = usb_rcvintpipe(dev, endpoint->bEndpointAddress);
1137 			usb_fill_int_urb(usbhid->urbin, dev, pipe, usbhid->inbuf, insize,
1138 					 hid_irq_in, hid, interval);
1139 			usbhid->urbin->transfer_dma = usbhid->inbuf_dma;
1140 			usbhid->urbin->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1141 		} else {
1142 			if (usbhid->urbout)
1143 				continue;
1144 			if (!(usbhid->urbout = usb_alloc_urb(0, GFP_KERNEL)))
1145 				goto fail;
1146 			pipe = usb_sndintpipe(dev, endpoint->bEndpointAddress);
1147 			usb_fill_int_urb(usbhid->urbout, dev, pipe, usbhid->outbuf, 0,
1148 					 hid_irq_out, hid, interval);
1149 			usbhid->urbout->transfer_dma = usbhid->outbuf_dma;
1150 			usbhid->urbout->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1151 		}
1152 	}
1153 
1154 	usbhid->urbctrl = usb_alloc_urb(0, GFP_KERNEL);
1155 	if (!usbhid->urbctrl) {
1156 		ret = -ENOMEM;
1157 		goto fail;
1158 	}
1159 
1160 	usb_fill_control_urb(usbhid->urbctrl, dev, 0, (void *) usbhid->cr,
1161 			     usbhid->ctrlbuf, 1, hid_ctrl, hid);
1162 	usbhid->urbctrl->transfer_dma = usbhid->ctrlbuf_dma;
1163 	usbhid->urbctrl->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1164 
1165 	set_bit(HID_STARTED, &usbhid->iofl);
1166 
1167 	if (hid->quirks & HID_QUIRK_ALWAYS_POLL) {
1168 		ret = usb_autopm_get_interface(usbhid->intf);
1169 		if (ret)
1170 			goto fail;
1171 		set_bit(HID_IN_POLLING, &usbhid->iofl);
1172 		usbhid->intf->needs_remote_wakeup = 1;
1173 		ret = hid_start_in(hid);
1174 		if (ret) {
1175 			dev_err(&hid->dev,
1176 				"failed to start in urb: %d\n", ret);
1177 		}
1178 		usb_autopm_put_interface(usbhid->intf);
1179 	}
1180 
1181 	/* Some keyboards don't work until their LEDs have been set.
1182 	 * Since BIOSes do set the LEDs, it must be safe for any device
1183 	 * that supports the keyboard boot protocol.
1184 	 * In addition, enable remote wakeup by default for all keyboard
1185 	 * devices supporting the boot protocol.
1186 	 */
1187 	if (interface->desc.bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT &&
1188 			interface->desc.bInterfaceProtocol ==
1189 				USB_INTERFACE_PROTOCOL_KEYBOARD) {
1190 		usbhid_set_leds(hid);
1191 		device_set_wakeup_enable(&dev->dev, 1);
1192 	}
1193 
1194 	mutex_unlock(&usbhid->mutex);
1195 	return 0;
1196 
1197 fail:
1198 	usb_free_urb(usbhid->urbin);
1199 	usb_free_urb(usbhid->urbout);
1200 	usb_free_urb(usbhid->urbctrl);
1201 	usbhid->urbin = NULL;
1202 	usbhid->urbout = NULL;
1203 	usbhid->urbctrl = NULL;
1204 	hid_free_buffers(dev, hid);
1205 	mutex_unlock(&usbhid->mutex);
1206 	return ret;
1207 }
1208 
usbhid_stop(struct hid_device * hid)1209 static void usbhid_stop(struct hid_device *hid)
1210 {
1211 	struct usbhid_device *usbhid = hid->driver_data;
1212 
1213 	if (WARN_ON(!usbhid))
1214 		return;
1215 
1216 	if (hid->quirks & HID_QUIRK_ALWAYS_POLL) {
1217 		clear_bit(HID_IN_POLLING, &usbhid->iofl);
1218 		usbhid->intf->needs_remote_wakeup = 0;
1219 	}
1220 
1221 	mutex_lock(&usbhid->mutex);
1222 
1223 	clear_bit(HID_STARTED, &usbhid->iofl);
1224 
1225 	spin_lock_irq(&usbhid->lock);	/* Sync with error and led handlers */
1226 	set_bit(HID_DISCONNECTED, &usbhid->iofl);
1227 	while (usbhid->ctrltail != usbhid->ctrlhead) {
1228 		if (usbhid->ctrl[usbhid->ctrltail].dir == USB_DIR_OUT) {
1229 			kfree(usbhid->ctrl[usbhid->ctrltail].raw_report);
1230 			usbhid->ctrl[usbhid->ctrltail].raw_report = NULL;
1231 		}
1232 
1233 		usbhid->ctrltail = (usbhid->ctrltail + 1) &
1234 			(HID_CONTROL_FIFO_SIZE - 1);
1235 	}
1236 	spin_unlock_irq(&usbhid->lock);
1237 
1238 	usb_kill_urb(usbhid->urbin);
1239 	usb_kill_urb(usbhid->urbout);
1240 	usb_kill_urb(usbhid->urbctrl);
1241 
1242 	hid_cancel_delayed_stuff(usbhid);
1243 
1244 	hid->claimed = 0;
1245 
1246 	usb_free_urb(usbhid->urbin);
1247 	usb_free_urb(usbhid->urbctrl);
1248 	usb_free_urb(usbhid->urbout);
1249 	usbhid->urbin = NULL; /* don't mess up next start */
1250 	usbhid->urbctrl = NULL;
1251 	usbhid->urbout = NULL;
1252 
1253 	hid_free_buffers(hid_to_usb_dev(hid), hid);
1254 
1255 	mutex_unlock(&usbhid->mutex);
1256 }
1257 
usbhid_power(struct hid_device * hid,int lvl)1258 static int usbhid_power(struct hid_device *hid, int lvl)
1259 {
1260 	struct usbhid_device *usbhid = hid->driver_data;
1261 	int r = 0;
1262 
1263 	switch (lvl) {
1264 	case PM_HINT_FULLON:
1265 		r = usb_autopm_get_interface(usbhid->intf);
1266 		break;
1267 
1268 	case PM_HINT_NORMAL:
1269 		usb_autopm_put_interface(usbhid->intf);
1270 		break;
1271 	}
1272 
1273 	return r;
1274 }
1275 
usbhid_request(struct hid_device * hid,struct hid_report * rep,int reqtype)1276 static void usbhid_request(struct hid_device *hid, struct hid_report *rep, int reqtype)
1277 {
1278 	switch (reqtype) {
1279 	case HID_REQ_GET_REPORT:
1280 		usbhid_submit_report(hid, rep, USB_DIR_IN);
1281 		break;
1282 	case HID_REQ_SET_REPORT:
1283 		usbhid_submit_report(hid, rep, USB_DIR_OUT);
1284 		break;
1285 	}
1286 }
1287 
usbhid_raw_request(struct hid_device * hid,unsigned char reportnum,__u8 * buf,size_t len,unsigned char rtype,int reqtype)1288 static int usbhid_raw_request(struct hid_device *hid, unsigned char reportnum,
1289 			      __u8 *buf, size_t len, unsigned char rtype,
1290 			      int reqtype)
1291 {
1292 	switch (reqtype) {
1293 	case HID_REQ_GET_REPORT:
1294 		return usbhid_get_raw_report(hid, reportnum, buf, len, rtype);
1295 	case HID_REQ_SET_REPORT:
1296 		return usbhid_set_raw_report(hid, reportnum, buf, len, rtype);
1297 	default:
1298 		return -EIO;
1299 	}
1300 }
1301 
usbhid_idle(struct hid_device * hid,int report,int idle,int reqtype)1302 static int usbhid_idle(struct hid_device *hid, int report, int idle,
1303 		int reqtype)
1304 {
1305 	struct usb_device *dev = hid_to_usb_dev(hid);
1306 	struct usb_interface *intf = to_usb_interface(hid->dev.parent);
1307 	struct usb_host_interface *interface = intf->cur_altsetting;
1308 	int ifnum = interface->desc.bInterfaceNumber;
1309 
1310 	if (reqtype != HID_REQ_SET_IDLE)
1311 		return -EINVAL;
1312 
1313 	return hid_set_idle(dev, ifnum, report, idle);
1314 }
1315 
usbhid_may_wakeup(struct hid_device * hid)1316 static bool usbhid_may_wakeup(struct hid_device *hid)
1317 {
1318 	struct usb_device *dev = hid_to_usb_dev(hid);
1319 
1320 	return device_may_wakeup(&dev->dev);
1321 }
1322 
1323 static const struct hid_ll_driver usb_hid_driver = {
1324 	.parse = usbhid_parse,
1325 	.start = usbhid_start,
1326 	.stop = usbhid_stop,
1327 	.open = usbhid_open,
1328 	.close = usbhid_close,
1329 	.power = usbhid_power,
1330 	.request = usbhid_request,
1331 	.wait = usbhid_wait_io,
1332 	.raw_request = usbhid_raw_request,
1333 	.output_report = usbhid_output_report,
1334 	.idle = usbhid_idle,
1335 	.may_wakeup = usbhid_may_wakeup,
1336 };
1337 
hid_is_usb(const struct hid_device * hdev)1338 bool hid_is_usb(const struct hid_device *hdev)
1339 {
1340 	return hdev->ll_driver == &usb_hid_driver;
1341 }
1342 EXPORT_SYMBOL_GPL(hid_is_usb);
1343 
usbhid_probe(struct usb_interface * intf,const struct usb_device_id * id)1344 static int usbhid_probe(struct usb_interface *intf, const struct usb_device_id *id)
1345 {
1346 	struct usb_host_interface *interface = intf->cur_altsetting;
1347 	struct usb_device *dev = interface_to_usbdev(intf);
1348 	struct usbhid_device *usbhid;
1349 	struct hid_device *hid;
1350 	unsigned int n, has_in = 0;
1351 	size_t len;
1352 	int ret;
1353 
1354 	dbg_hid("HID probe called for ifnum %d\n",
1355 			intf->altsetting->desc.bInterfaceNumber);
1356 
1357 	for (n = 0; n < interface->desc.bNumEndpoints; n++)
1358 		if (usb_endpoint_is_int_in(&interface->endpoint[n].desc))
1359 			has_in++;
1360 	if (!has_in) {
1361 		hid_err(intf, "couldn't find an input interrupt endpoint\n");
1362 		return -ENODEV;
1363 	}
1364 
1365 	hid = hid_allocate_device();
1366 	if (IS_ERR(hid))
1367 		return PTR_ERR(hid);
1368 
1369 	usb_set_intfdata(intf, hid);
1370 	hid->ll_driver = &usb_hid_driver;
1371 	hid->ff_init = hid_pidff_init;
1372 #ifdef CONFIG_USB_HIDDEV
1373 	hid->hiddev_connect = hiddev_connect;
1374 	hid->hiddev_disconnect = hiddev_disconnect;
1375 	hid->hiddev_hid_event = hiddev_hid_event;
1376 	hid->hiddev_report_event = hiddev_report_event;
1377 #endif
1378 	hid->dev.parent = &intf->dev;
1379 	device_set_node(&hid->dev, dev_fwnode(&intf->dev));
1380 	hid->bus = BUS_USB;
1381 	hid->vendor = le16_to_cpu(dev->descriptor.idVendor);
1382 	hid->product = le16_to_cpu(dev->descriptor.idProduct);
1383 	hid->version = le16_to_cpu(dev->descriptor.bcdDevice);
1384 	hid->name[0] = 0;
1385 	if (intf->cur_altsetting->desc.bInterfaceProtocol ==
1386 			USB_INTERFACE_PROTOCOL_MOUSE)
1387 		hid->type = HID_TYPE_USBMOUSE;
1388 	else if (intf->cur_altsetting->desc.bInterfaceProtocol == 0)
1389 		hid->type = HID_TYPE_USBNONE;
1390 
1391 	if (dev->manufacturer)
1392 		strscpy(hid->name, dev->manufacturer, sizeof(hid->name));
1393 
1394 	if (dev->product) {
1395 		if (dev->manufacturer)
1396 			strlcat(hid->name, " ", sizeof(hid->name));
1397 		strlcat(hid->name, dev->product, sizeof(hid->name));
1398 	}
1399 
1400 	if (!strlen(hid->name))
1401 		snprintf(hid->name, sizeof(hid->name), "HID %04x:%04x",
1402 			 le16_to_cpu(dev->descriptor.idVendor),
1403 			 le16_to_cpu(dev->descriptor.idProduct));
1404 
1405 	usb_make_path(dev, hid->phys, sizeof(hid->phys));
1406 	strlcat(hid->phys, "/input", sizeof(hid->phys));
1407 	len = strlen(hid->phys);
1408 	if (len < sizeof(hid->phys) - 1)
1409 		snprintf(hid->phys + len, sizeof(hid->phys) - len,
1410 			 "%d", intf->altsetting[0].desc.bInterfaceNumber);
1411 
1412 	if (usb_string(dev, dev->descriptor.iSerialNumber, hid->uniq, 64) <= 0)
1413 		hid->uniq[0] = 0;
1414 
1415 	usbhid = kzalloc(sizeof(*usbhid), GFP_KERNEL);
1416 	if (usbhid == NULL) {
1417 		ret = -ENOMEM;
1418 		goto err;
1419 	}
1420 
1421 	hid->driver_data = usbhid;
1422 	usbhid->hid = hid;
1423 	usbhid->intf = intf;
1424 	usbhid->ifnum = interface->desc.bInterfaceNumber;
1425 
1426 	init_waitqueue_head(&usbhid->wait);
1427 	INIT_WORK(&usbhid->reset_work, hid_reset);
1428 	timer_setup(&usbhid->io_retry, hid_retry_timeout, 0);
1429 	spin_lock_init(&usbhid->lock);
1430 	mutex_init(&usbhid->mutex);
1431 
1432 	ret = hid_add_device(hid);
1433 	if (ret) {
1434 		if (ret != -ENODEV)
1435 			hid_err(intf, "can't add hid device: %d\n", ret);
1436 		goto err_free;
1437 	}
1438 
1439 	return 0;
1440 err_free:
1441 	kfree(usbhid);
1442 err:
1443 	hid_destroy_device(hid);
1444 	return ret;
1445 }
1446 
usbhid_disconnect(struct usb_interface * intf)1447 static void usbhid_disconnect(struct usb_interface *intf)
1448 {
1449 	struct hid_device *hid = usb_get_intfdata(intf);
1450 	struct usbhid_device *usbhid;
1451 
1452 	if (WARN_ON(!hid))
1453 		return;
1454 
1455 	usbhid = hid->driver_data;
1456 	spin_lock_irq(&usbhid->lock);	/* Sync with error and led handlers */
1457 	set_bit(HID_DISCONNECTED, &usbhid->iofl);
1458 	spin_unlock_irq(&usbhid->lock);
1459 	hid_destroy_device(hid);
1460 	kfree(usbhid);
1461 }
1462 
hid_cancel_delayed_stuff(struct usbhid_device * usbhid)1463 static void hid_cancel_delayed_stuff(struct usbhid_device *usbhid)
1464 {
1465 	timer_delete_sync(&usbhid->io_retry);
1466 	cancel_work_sync(&usbhid->reset_work);
1467 }
1468 
hid_cease_io(struct usbhid_device * usbhid)1469 static void hid_cease_io(struct usbhid_device *usbhid)
1470 {
1471 	timer_delete_sync(&usbhid->io_retry);
1472 	usb_kill_urb(usbhid->urbin);
1473 	usb_kill_urb(usbhid->urbctrl);
1474 	usb_kill_urb(usbhid->urbout);
1475 }
1476 
hid_restart_io(struct hid_device * hid)1477 static void hid_restart_io(struct hid_device *hid)
1478 {
1479 	struct usbhid_device *usbhid = hid->driver_data;
1480 	int clear_halt = test_bit(HID_CLEAR_HALT, &usbhid->iofl);
1481 	int reset_pending = test_bit(HID_RESET_PENDING, &usbhid->iofl);
1482 
1483 	spin_lock_irq(&usbhid->lock);
1484 	clear_bit(HID_SUSPENDED, &usbhid->iofl);
1485 	usbhid_mark_busy(usbhid);
1486 
1487 	if (clear_halt || reset_pending)
1488 		schedule_work(&usbhid->reset_work);
1489 	usbhid->retry_delay = 0;
1490 	spin_unlock_irq(&usbhid->lock);
1491 
1492 	if (reset_pending || !test_bit(HID_STARTED, &usbhid->iofl))
1493 		return;
1494 
1495 	if (!clear_halt) {
1496 		if (hid_start_in(hid) < 0)
1497 			hid_io_error(hid);
1498 	}
1499 
1500 	spin_lock_irq(&usbhid->lock);
1501 	if (usbhid->urbout && !test_bit(HID_OUT_RUNNING, &usbhid->iofl))
1502 		usbhid_restart_out_queue(usbhid);
1503 	if (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl))
1504 		usbhid_restart_ctrl_queue(usbhid);
1505 	spin_unlock_irq(&usbhid->lock);
1506 }
1507 
1508 /* Treat USB reset pretty much the same as suspend/resume */
hid_pre_reset(struct usb_interface * intf)1509 static int hid_pre_reset(struct usb_interface *intf)
1510 {
1511 	struct hid_device *hid = usb_get_intfdata(intf);
1512 	struct usbhid_device *usbhid = hid->driver_data;
1513 
1514 	spin_lock_irq(&usbhid->lock);
1515 	set_bit(HID_RESET_PENDING, &usbhid->iofl);
1516 	spin_unlock_irq(&usbhid->lock);
1517 	hid_cease_io(usbhid);
1518 
1519 	return 0;
1520 }
1521 
1522 /* Same routine used for post_reset and reset_resume */
hid_post_reset(struct usb_interface * intf)1523 static int hid_post_reset(struct usb_interface *intf)
1524 {
1525 	struct usb_device *dev = interface_to_usbdev (intf);
1526 	struct hid_device *hid = usb_get_intfdata(intf);
1527 	struct usbhid_device *usbhid = hid->driver_data;
1528 	struct usb_host_interface *interface = intf->cur_altsetting;
1529 	int status;
1530 	char *rdesc;
1531 
1532 	/* Fetch and examine the HID report descriptor. If this
1533 	 * has changed, then rebind. Since usbcore's check of the
1534 	 * configuration descriptors passed, we already know that
1535 	 * the size of the HID report descriptor has not changed.
1536 	 */
1537 	rdesc = kmalloc(hid->dev_rsize, GFP_KERNEL);
1538 	if (!rdesc)
1539 		return -ENOMEM;
1540 
1541 	status = hid_get_class_descriptor(dev,
1542 				interface->desc.bInterfaceNumber,
1543 				HID_DT_REPORT, rdesc, hid->dev_rsize);
1544 	if (status < 0) {
1545 		dbg_hid("reading report descriptor failed (post_reset)\n");
1546 		kfree(rdesc);
1547 		return status;
1548 	}
1549 	status = memcmp(rdesc, hid->dev_rdesc, hid->dev_rsize);
1550 	kfree(rdesc);
1551 	if (status != 0) {
1552 		dbg_hid("report descriptor changed\n");
1553 		return -EPERM;
1554 	}
1555 
1556 	/* No need to do another reset or clear a halted endpoint */
1557 	spin_lock_irq(&usbhid->lock);
1558 	clear_bit(HID_RESET_PENDING, &usbhid->iofl);
1559 	clear_bit(HID_CLEAR_HALT, &usbhid->iofl);
1560 	spin_unlock_irq(&usbhid->lock);
1561 	hid_set_idle(dev, intf->cur_altsetting->desc.bInterfaceNumber, 0, 0);
1562 
1563 	hid_restart_io(hid);
1564 
1565 	return 0;
1566 }
1567 
hid_resume_common(struct hid_device * hid,bool driver_suspended)1568 static int hid_resume_common(struct hid_device *hid, bool driver_suspended)
1569 {
1570 	int status = 0;
1571 
1572 	hid_restart_io(hid);
1573 	if (driver_suspended)
1574 		status = hid_driver_resume(hid);
1575 	return status;
1576 }
1577 
hid_suspend(struct usb_interface * intf,pm_message_t message)1578 static int hid_suspend(struct usb_interface *intf, pm_message_t message)
1579 {
1580 	struct hid_device *hid = usb_get_intfdata(intf);
1581 	struct usbhid_device *usbhid = hid->driver_data;
1582 	int status = 0;
1583 	bool driver_suspended = false;
1584 	unsigned int ledcount;
1585 
1586 	if (PMSG_IS_AUTO(message)) {
1587 		ledcount = hidinput_count_leds(hid);
1588 		spin_lock_irq(&usbhid->lock);	/* Sync with error handler */
1589 		if (!test_bit(HID_RESET_PENDING, &usbhid->iofl)
1590 		    && !test_bit(HID_CLEAR_HALT, &usbhid->iofl)
1591 		    && !test_bit(HID_OUT_RUNNING, &usbhid->iofl)
1592 		    && !test_bit(HID_CTRL_RUNNING, &usbhid->iofl)
1593 		    && !test_bit(HID_KEYS_PRESSED, &usbhid->iofl)
1594 		    && (!ledcount || ignoreled))
1595 		{
1596 			set_bit(HID_SUSPENDED, &usbhid->iofl);
1597 			spin_unlock_irq(&usbhid->lock);
1598 			status = hid_driver_suspend(hid, message);
1599 			if (status < 0)
1600 				goto failed;
1601 			driver_suspended = true;
1602 		} else {
1603 			usbhid_mark_busy(usbhid);
1604 			spin_unlock_irq(&usbhid->lock);
1605 			return -EBUSY;
1606 		}
1607 
1608 	} else {
1609 		/* TODO: resume() might need to handle suspend failure */
1610 		status = hid_driver_suspend(hid, message);
1611 		driver_suspended = true;
1612 		spin_lock_irq(&usbhid->lock);
1613 		set_bit(HID_SUSPENDED, &usbhid->iofl);
1614 		spin_unlock_irq(&usbhid->lock);
1615 		if (usbhid_wait_io(hid) < 0)
1616 			status = -EIO;
1617 	}
1618 
1619 	hid_cancel_delayed_stuff(usbhid);
1620 	hid_cease_io(usbhid);
1621 
1622 	if (PMSG_IS_AUTO(message) && test_bit(HID_KEYS_PRESSED, &usbhid->iofl)) {
1623 		/* lost race against keypresses */
1624 		status = -EBUSY;
1625 		goto failed;
1626 	}
1627 	dev_dbg(&intf->dev, "suspend\n");
1628 	return status;
1629 
1630  failed:
1631 	hid_resume_common(hid, driver_suspended);
1632 	return status;
1633 }
1634 
hid_resume(struct usb_interface * intf)1635 static int hid_resume(struct usb_interface *intf)
1636 {
1637 	struct hid_device *hid = usb_get_intfdata (intf);
1638 	int status;
1639 
1640 	status = hid_resume_common(hid, true);
1641 	dev_dbg(&intf->dev, "resume status %d\n", status);
1642 	return 0;
1643 }
1644 
hid_reset_resume(struct usb_interface * intf)1645 static int hid_reset_resume(struct usb_interface *intf)
1646 {
1647 	struct hid_device *hid = usb_get_intfdata(intf);
1648 	int status;
1649 
1650 	status = hid_post_reset(intf);
1651 	if (status >= 0) {
1652 		int ret = hid_driver_reset_resume(hid);
1653 		if (ret < 0)
1654 			status = ret;
1655 	}
1656 	return status;
1657 }
1658 
1659 static const struct usb_device_id hid_usb_ids[] = {
1660 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
1661 		.bInterfaceClass = USB_INTERFACE_CLASS_HID },
1662 	{ }						/* Terminating entry */
1663 };
1664 
1665 MODULE_DEVICE_TABLE (usb, hid_usb_ids);
1666 
1667 static struct usb_driver hid_driver = {
1668 	.name =		"usbhid",
1669 	.probe =	usbhid_probe,
1670 	.disconnect =	usbhid_disconnect,
1671 	.suspend =	pm_ptr(hid_suspend),
1672 	.resume =	pm_ptr(hid_resume),
1673 	.reset_resume =	pm_ptr(hid_reset_resume),
1674 	.pre_reset =	hid_pre_reset,
1675 	.post_reset =	hid_post_reset,
1676 	.id_table =	hid_usb_ids,
1677 	.supports_autosuspend = 1,
1678 };
1679 
usbhid_find_interface(int minor)1680 struct usb_interface *usbhid_find_interface(int minor)
1681 {
1682 	return usb_find_interface(&hid_driver, minor);
1683 }
1684 
hid_init(void)1685 static int __init hid_init(void)
1686 {
1687 	int retval;
1688 
1689 	retval = hid_quirks_init(quirks_param, BUS_USB, MAX_USBHID_BOOT_QUIRKS);
1690 	if (retval)
1691 		goto usbhid_quirks_init_fail;
1692 	retval = usb_register(&hid_driver);
1693 	if (retval)
1694 		goto usb_register_fail;
1695 	pr_info(KBUILD_MODNAME ": " DRIVER_DESC "\n");
1696 
1697 	return 0;
1698 usb_register_fail:
1699 	hid_quirks_exit(BUS_USB);
1700 usbhid_quirks_init_fail:
1701 	return retval;
1702 }
1703 
hid_exit(void)1704 static void __exit hid_exit(void)
1705 {
1706 	usb_deregister(&hid_driver);
1707 	hid_quirks_exit(BUS_USB);
1708 }
1709 
1710 module_init(hid_init);
1711 module_exit(hid_exit);
1712 
1713 MODULE_AUTHOR("Andreas Gal");
1714 MODULE_AUTHOR("Vojtech Pavlik");
1715 MODULE_AUTHOR("Jiri Kosina");
1716 MODULE_DESCRIPTION(DRIVER_DESC);
1717 MODULE_LICENSE("GPL");
1718