xref: /linux/drivers/media/usb/uvc/uvc_ctrl.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  *      uvc_ctrl.c  --  USB Video Class driver - Controls
3  *
4  *      Copyright (C) 2005-2010
5  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
6  *
7  *      This program is free software; you can redistribute it and/or modify
8  *      it under the terms of the GNU General Public License as published by
9  *      the Free Software Foundation; either version 2 of the License, or
10  *      (at your option) any later version.
11  *
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/list.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/uaccess.h>
19 #include <linux/usb.h>
20 #include <linux/videodev2.h>
21 #include <linux/vmalloc.h>
22 #include <linux/wait.h>
23 #include <linux/atomic.h>
24 #include <media/v4l2-ctrls.h>
25 
26 #include "uvcvideo.h"
27 
28 #define UVC_CTRL_DATA_CURRENT	0
29 #define UVC_CTRL_DATA_BACKUP	1
30 #define UVC_CTRL_DATA_MIN	2
31 #define UVC_CTRL_DATA_MAX	3
32 #define UVC_CTRL_DATA_RES	4
33 #define UVC_CTRL_DATA_DEF	5
34 #define UVC_CTRL_DATA_LAST	6
35 
36 /* ------------------------------------------------------------------------
37  * Controls
38  */
39 
40 static struct uvc_control_info uvc_ctrls[] = {
41 	{
42 		.entity		= UVC_GUID_UVC_PROCESSING,
43 		.selector	= UVC_PU_BRIGHTNESS_CONTROL,
44 		.index		= 0,
45 		.size		= 2,
46 		.flags		= UVC_CTRL_FLAG_SET_CUR
47 				| UVC_CTRL_FLAG_GET_RANGE
48 				| UVC_CTRL_FLAG_RESTORE,
49 	},
50 	{
51 		.entity		= UVC_GUID_UVC_PROCESSING,
52 		.selector	= UVC_PU_CONTRAST_CONTROL,
53 		.index		= 1,
54 		.size		= 2,
55 		.flags		= UVC_CTRL_FLAG_SET_CUR
56 				| UVC_CTRL_FLAG_GET_RANGE
57 				| UVC_CTRL_FLAG_RESTORE,
58 	},
59 	{
60 		.entity		= UVC_GUID_UVC_PROCESSING,
61 		.selector	= UVC_PU_HUE_CONTROL,
62 		.index		= 2,
63 		.size		= 2,
64 		.flags		= UVC_CTRL_FLAG_SET_CUR
65 				| UVC_CTRL_FLAG_GET_RANGE
66 				| UVC_CTRL_FLAG_RESTORE
67 				| UVC_CTRL_FLAG_AUTO_UPDATE,
68 	},
69 	{
70 		.entity		= UVC_GUID_UVC_PROCESSING,
71 		.selector	= UVC_PU_SATURATION_CONTROL,
72 		.index		= 3,
73 		.size		= 2,
74 		.flags		= UVC_CTRL_FLAG_SET_CUR
75 				| UVC_CTRL_FLAG_GET_RANGE
76 				| UVC_CTRL_FLAG_RESTORE,
77 	},
78 	{
79 		.entity		= UVC_GUID_UVC_PROCESSING,
80 		.selector	= UVC_PU_SHARPNESS_CONTROL,
81 		.index		= 4,
82 		.size		= 2,
83 		.flags		= UVC_CTRL_FLAG_SET_CUR
84 				| UVC_CTRL_FLAG_GET_RANGE
85 				| UVC_CTRL_FLAG_RESTORE,
86 	},
87 	{
88 		.entity		= UVC_GUID_UVC_PROCESSING,
89 		.selector	= UVC_PU_GAMMA_CONTROL,
90 		.index		= 5,
91 		.size		= 2,
92 		.flags		= UVC_CTRL_FLAG_SET_CUR
93 				| UVC_CTRL_FLAG_GET_RANGE
94 				| UVC_CTRL_FLAG_RESTORE,
95 	},
96 	{
97 		.entity		= UVC_GUID_UVC_PROCESSING,
98 		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_CONTROL,
99 		.index		= 6,
100 		.size		= 2,
101 		.flags		= UVC_CTRL_FLAG_SET_CUR
102 				| UVC_CTRL_FLAG_GET_RANGE
103 				| UVC_CTRL_FLAG_RESTORE
104 				| UVC_CTRL_FLAG_AUTO_UPDATE,
105 	},
106 	{
107 		.entity		= UVC_GUID_UVC_PROCESSING,
108 		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_CONTROL,
109 		.index		= 7,
110 		.size		= 4,
111 		.flags		= UVC_CTRL_FLAG_SET_CUR
112 				| UVC_CTRL_FLAG_GET_RANGE
113 				| UVC_CTRL_FLAG_RESTORE
114 				| UVC_CTRL_FLAG_AUTO_UPDATE,
115 	},
116 	{
117 		.entity		= UVC_GUID_UVC_PROCESSING,
118 		.selector	= UVC_PU_BACKLIGHT_COMPENSATION_CONTROL,
119 		.index		= 8,
120 		.size		= 2,
121 		.flags		= UVC_CTRL_FLAG_SET_CUR
122 				| UVC_CTRL_FLAG_GET_RANGE
123 				| UVC_CTRL_FLAG_RESTORE,
124 	},
125 	{
126 		.entity		= UVC_GUID_UVC_PROCESSING,
127 		.selector	= UVC_PU_GAIN_CONTROL,
128 		.index		= 9,
129 		.size		= 2,
130 		.flags		= UVC_CTRL_FLAG_SET_CUR
131 				| UVC_CTRL_FLAG_GET_RANGE
132 				| UVC_CTRL_FLAG_RESTORE,
133 	},
134 	{
135 		.entity		= UVC_GUID_UVC_PROCESSING,
136 		.selector	= UVC_PU_POWER_LINE_FREQUENCY_CONTROL,
137 		.index		= 10,
138 		.size		= 1,
139 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
140 				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
141 	},
142 	{
143 		.entity		= UVC_GUID_UVC_PROCESSING,
144 		.selector	= UVC_PU_HUE_AUTO_CONTROL,
145 		.index		= 11,
146 		.size		= 1,
147 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
148 				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
149 	},
150 	{
151 		.entity		= UVC_GUID_UVC_PROCESSING,
152 		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL,
153 		.index		= 12,
154 		.size		= 1,
155 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
156 				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
157 	},
158 	{
159 		.entity		= UVC_GUID_UVC_PROCESSING,
160 		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL,
161 		.index		= 13,
162 		.size		= 1,
163 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
164 				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
165 	},
166 	{
167 		.entity		= UVC_GUID_UVC_PROCESSING,
168 		.selector	= UVC_PU_DIGITAL_MULTIPLIER_CONTROL,
169 		.index		= 14,
170 		.size		= 2,
171 		.flags		= UVC_CTRL_FLAG_SET_CUR
172 				| UVC_CTRL_FLAG_GET_RANGE
173 				| UVC_CTRL_FLAG_RESTORE,
174 	},
175 	{
176 		.entity		= UVC_GUID_UVC_PROCESSING,
177 		.selector	= UVC_PU_DIGITAL_MULTIPLIER_LIMIT_CONTROL,
178 		.index		= 15,
179 		.size		= 2,
180 		.flags		= UVC_CTRL_FLAG_SET_CUR
181 				| UVC_CTRL_FLAG_GET_RANGE
182 				| UVC_CTRL_FLAG_RESTORE,
183 	},
184 	{
185 		.entity		= UVC_GUID_UVC_PROCESSING,
186 		.selector	= UVC_PU_ANALOG_VIDEO_STANDARD_CONTROL,
187 		.index		= 16,
188 		.size		= 1,
189 		.flags		= UVC_CTRL_FLAG_GET_CUR,
190 	},
191 	{
192 		.entity		= UVC_GUID_UVC_PROCESSING,
193 		.selector	= UVC_PU_ANALOG_LOCK_STATUS_CONTROL,
194 		.index		= 17,
195 		.size		= 1,
196 		.flags		= UVC_CTRL_FLAG_GET_CUR,
197 	},
198 	{
199 		.entity		= UVC_GUID_UVC_CAMERA,
200 		.selector	= UVC_CT_SCANNING_MODE_CONTROL,
201 		.index		= 0,
202 		.size		= 1,
203 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
204 				| UVC_CTRL_FLAG_RESTORE,
205 	},
206 	{
207 		.entity		= UVC_GUID_UVC_CAMERA,
208 		.selector	= UVC_CT_AE_MODE_CONTROL,
209 		.index		= 1,
210 		.size		= 1,
211 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
212 				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_GET_RES
213 				| UVC_CTRL_FLAG_RESTORE,
214 	},
215 	{
216 		.entity		= UVC_GUID_UVC_CAMERA,
217 		.selector	= UVC_CT_AE_PRIORITY_CONTROL,
218 		.index		= 2,
219 		.size		= 1,
220 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
221 				| UVC_CTRL_FLAG_RESTORE,
222 	},
223 	{
224 		.entity		= UVC_GUID_UVC_CAMERA,
225 		.selector	= UVC_CT_EXPOSURE_TIME_ABSOLUTE_CONTROL,
226 		.index		= 3,
227 		.size		= 4,
228 		.flags		= UVC_CTRL_FLAG_SET_CUR
229 				| UVC_CTRL_FLAG_GET_RANGE
230 				| UVC_CTRL_FLAG_RESTORE,
231 	},
232 	{
233 		.entity		= UVC_GUID_UVC_CAMERA,
234 		.selector	= UVC_CT_EXPOSURE_TIME_RELATIVE_CONTROL,
235 		.index		= 4,
236 		.size		= 1,
237 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_RESTORE,
238 	},
239 	{
240 		.entity		= UVC_GUID_UVC_CAMERA,
241 		.selector	= UVC_CT_FOCUS_ABSOLUTE_CONTROL,
242 		.index		= 5,
243 		.size		= 2,
244 		.flags		= UVC_CTRL_FLAG_SET_CUR
245 				| UVC_CTRL_FLAG_GET_RANGE
246 				| UVC_CTRL_FLAG_RESTORE
247 				| UVC_CTRL_FLAG_AUTO_UPDATE,
248 	},
249 	{
250 		.entity		= UVC_GUID_UVC_CAMERA,
251 		.selector	= UVC_CT_FOCUS_RELATIVE_CONTROL,
252 		.index		= 6,
253 		.size		= 2,
254 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_MIN
255 				| UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES
256 				| UVC_CTRL_FLAG_GET_DEF
257 				| UVC_CTRL_FLAG_AUTO_UPDATE,
258 	},
259 	{
260 		.entity		= UVC_GUID_UVC_CAMERA,
261 		.selector	= UVC_CT_IRIS_ABSOLUTE_CONTROL,
262 		.index		= 7,
263 		.size		= 2,
264 		.flags		= UVC_CTRL_FLAG_SET_CUR
265 				| UVC_CTRL_FLAG_GET_RANGE
266 				| UVC_CTRL_FLAG_RESTORE
267 				| UVC_CTRL_FLAG_AUTO_UPDATE,
268 	},
269 	{
270 		.entity		= UVC_GUID_UVC_CAMERA,
271 		.selector	= UVC_CT_IRIS_RELATIVE_CONTROL,
272 		.index		= 8,
273 		.size		= 1,
274 		.flags		= UVC_CTRL_FLAG_SET_CUR
275 				| UVC_CTRL_FLAG_AUTO_UPDATE,
276 	},
277 	{
278 		.entity		= UVC_GUID_UVC_CAMERA,
279 		.selector	= UVC_CT_ZOOM_ABSOLUTE_CONTROL,
280 		.index		= 9,
281 		.size		= 2,
282 		.flags		= UVC_CTRL_FLAG_SET_CUR
283 				| UVC_CTRL_FLAG_GET_RANGE
284 				| UVC_CTRL_FLAG_RESTORE
285 				| UVC_CTRL_FLAG_AUTO_UPDATE,
286 	},
287 	{
288 		.entity		= UVC_GUID_UVC_CAMERA,
289 		.selector	= UVC_CT_ZOOM_RELATIVE_CONTROL,
290 		.index		= 10,
291 		.size		= 3,
292 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_MIN
293 				| UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES
294 				| UVC_CTRL_FLAG_GET_DEF
295 				| UVC_CTRL_FLAG_AUTO_UPDATE,
296 	},
297 	{
298 		.entity		= UVC_GUID_UVC_CAMERA,
299 		.selector	= UVC_CT_PANTILT_ABSOLUTE_CONTROL,
300 		.index		= 11,
301 		.size		= 8,
302 		.flags		= UVC_CTRL_FLAG_SET_CUR
303 				| UVC_CTRL_FLAG_GET_RANGE
304 				| UVC_CTRL_FLAG_RESTORE
305 				| UVC_CTRL_FLAG_AUTO_UPDATE,
306 	},
307 	{
308 		.entity		= UVC_GUID_UVC_CAMERA,
309 		.selector	= UVC_CT_PANTILT_RELATIVE_CONTROL,
310 		.index		= 12,
311 		.size		= 4,
312 		.flags		= UVC_CTRL_FLAG_SET_CUR
313 				| UVC_CTRL_FLAG_GET_RANGE
314 				| UVC_CTRL_FLAG_AUTO_UPDATE,
315 	},
316 	{
317 		.entity		= UVC_GUID_UVC_CAMERA,
318 		.selector	= UVC_CT_ROLL_ABSOLUTE_CONTROL,
319 		.index		= 13,
320 		.size		= 2,
321 		.flags		= UVC_CTRL_FLAG_SET_CUR
322 				| UVC_CTRL_FLAG_GET_RANGE
323 				| UVC_CTRL_FLAG_RESTORE
324 				| UVC_CTRL_FLAG_AUTO_UPDATE,
325 	},
326 	{
327 		.entity		= UVC_GUID_UVC_CAMERA,
328 		.selector	= UVC_CT_ROLL_RELATIVE_CONTROL,
329 		.index		= 14,
330 		.size		= 2,
331 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_MIN
332 				| UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES
333 				| UVC_CTRL_FLAG_GET_DEF
334 				| UVC_CTRL_FLAG_AUTO_UPDATE,
335 	},
336 	{
337 		.entity		= UVC_GUID_UVC_CAMERA,
338 		.selector	= UVC_CT_FOCUS_AUTO_CONTROL,
339 		.index		= 17,
340 		.size		= 1,
341 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
342 				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
343 	},
344 	{
345 		.entity		= UVC_GUID_UVC_CAMERA,
346 		.selector	= UVC_CT_PRIVACY_CONTROL,
347 		.index		= 18,
348 		.size		= 1,
349 		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
350 				| UVC_CTRL_FLAG_RESTORE
351 				| UVC_CTRL_FLAG_AUTO_UPDATE,
352 	},
353 };
354 
355 static struct uvc_menu_info power_line_frequency_controls[] = {
356 	{ 0, "Disabled" },
357 	{ 1, "50 Hz" },
358 	{ 2, "60 Hz" },
359 };
360 
361 static struct uvc_menu_info exposure_auto_controls[] = {
362 	{ 2, "Auto Mode" },
363 	{ 1, "Manual Mode" },
364 	{ 4, "Shutter Priority Mode" },
365 	{ 8, "Aperture Priority Mode" },
366 };
367 
368 static __s32 uvc_ctrl_get_zoom(struct uvc_control_mapping *mapping,
369 	__u8 query, const __u8 *data)
370 {
371 	__s8 zoom = (__s8)data[0];
372 
373 	switch (query) {
374 	case UVC_GET_CUR:
375 		return (zoom == 0) ? 0 : (zoom > 0 ? data[2] : -data[2]);
376 
377 	case UVC_GET_MIN:
378 	case UVC_GET_MAX:
379 	case UVC_GET_RES:
380 	case UVC_GET_DEF:
381 	default:
382 		return data[2];
383 	}
384 }
385 
386 static void uvc_ctrl_set_zoom(struct uvc_control_mapping *mapping,
387 	__s32 value, __u8 *data)
388 {
389 	data[0] = value == 0 ? 0 : (value > 0) ? 1 : 0xff;
390 	data[2] = min((int)abs(value), 0xff);
391 }
392 
393 static __s32 uvc_ctrl_get_rel_speed(struct uvc_control_mapping *mapping,
394 	__u8 query, const __u8 *data)
395 {
396 	unsigned int first = mapping->offset / 8;
397 	__s8 rel = (__s8)data[first];
398 
399 	switch (query) {
400 	case UVC_GET_CUR:
401 		return (rel == 0) ? 0 : (rel > 0 ? data[first+1]
402 						 : -data[first+1]);
403 	case UVC_GET_MIN:
404 		return -data[first+1];
405 	case UVC_GET_MAX:
406 	case UVC_GET_RES:
407 	case UVC_GET_DEF:
408 	default:
409 		return data[first+1];
410 	}
411 }
412 
413 static void uvc_ctrl_set_rel_speed(struct uvc_control_mapping *mapping,
414 	__s32 value, __u8 *data)
415 {
416 	unsigned int first = mapping->offset / 8;
417 
418 	data[first] = value == 0 ? 0 : (value > 0) ? 1 : 0xff;
419 	data[first+1] = min_t(int, abs(value), 0xff);
420 }
421 
422 static struct uvc_control_mapping uvc_ctrl_mappings[] = {
423 	{
424 		.id		= V4L2_CID_BRIGHTNESS,
425 		.name		= "Brightness",
426 		.entity		= UVC_GUID_UVC_PROCESSING,
427 		.selector	= UVC_PU_BRIGHTNESS_CONTROL,
428 		.size		= 16,
429 		.offset		= 0,
430 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
431 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
432 	},
433 	{
434 		.id		= V4L2_CID_CONTRAST,
435 		.name		= "Contrast",
436 		.entity		= UVC_GUID_UVC_PROCESSING,
437 		.selector	= UVC_PU_CONTRAST_CONTROL,
438 		.size		= 16,
439 		.offset		= 0,
440 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
441 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
442 	},
443 	{
444 		.id		= V4L2_CID_HUE,
445 		.name		= "Hue",
446 		.entity		= UVC_GUID_UVC_PROCESSING,
447 		.selector	= UVC_PU_HUE_CONTROL,
448 		.size		= 16,
449 		.offset		= 0,
450 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
451 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
452 		.master_id	= V4L2_CID_HUE_AUTO,
453 		.master_manual	= 0,
454 	},
455 	{
456 		.id		= V4L2_CID_SATURATION,
457 		.name		= "Saturation",
458 		.entity		= UVC_GUID_UVC_PROCESSING,
459 		.selector	= UVC_PU_SATURATION_CONTROL,
460 		.size		= 16,
461 		.offset		= 0,
462 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
463 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
464 	},
465 	{
466 		.id		= V4L2_CID_SHARPNESS,
467 		.name		= "Sharpness",
468 		.entity		= UVC_GUID_UVC_PROCESSING,
469 		.selector	= UVC_PU_SHARPNESS_CONTROL,
470 		.size		= 16,
471 		.offset		= 0,
472 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
473 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
474 	},
475 	{
476 		.id		= V4L2_CID_GAMMA,
477 		.name		= "Gamma",
478 		.entity		= UVC_GUID_UVC_PROCESSING,
479 		.selector	= UVC_PU_GAMMA_CONTROL,
480 		.size		= 16,
481 		.offset		= 0,
482 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
483 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
484 	},
485 	{
486 		.id		= V4L2_CID_BACKLIGHT_COMPENSATION,
487 		.name		= "Backlight Compensation",
488 		.entity		= UVC_GUID_UVC_PROCESSING,
489 		.selector	= UVC_PU_BACKLIGHT_COMPENSATION_CONTROL,
490 		.size		= 16,
491 		.offset		= 0,
492 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
493 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
494 	},
495 	{
496 		.id		= V4L2_CID_GAIN,
497 		.name		= "Gain",
498 		.entity		= UVC_GUID_UVC_PROCESSING,
499 		.selector	= UVC_PU_GAIN_CONTROL,
500 		.size		= 16,
501 		.offset		= 0,
502 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
503 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
504 	},
505 	{
506 		.id		= V4L2_CID_POWER_LINE_FREQUENCY,
507 		.name		= "Power Line Frequency",
508 		.entity		= UVC_GUID_UVC_PROCESSING,
509 		.selector	= UVC_PU_POWER_LINE_FREQUENCY_CONTROL,
510 		.size		= 2,
511 		.offset		= 0,
512 		.v4l2_type	= V4L2_CTRL_TYPE_MENU,
513 		.data_type	= UVC_CTRL_DATA_TYPE_ENUM,
514 		.menu_info	= power_line_frequency_controls,
515 		.menu_count	= ARRAY_SIZE(power_line_frequency_controls),
516 	},
517 	{
518 		.id		= V4L2_CID_HUE_AUTO,
519 		.name		= "Hue, Auto",
520 		.entity		= UVC_GUID_UVC_PROCESSING,
521 		.selector	= UVC_PU_HUE_AUTO_CONTROL,
522 		.size		= 1,
523 		.offset		= 0,
524 		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
525 		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
526 		.slave_ids	= { V4L2_CID_HUE, },
527 	},
528 	{
529 		.id		= V4L2_CID_EXPOSURE_AUTO,
530 		.name		= "Exposure, Auto",
531 		.entity		= UVC_GUID_UVC_CAMERA,
532 		.selector	= UVC_CT_AE_MODE_CONTROL,
533 		.size		= 4,
534 		.offset		= 0,
535 		.v4l2_type	= V4L2_CTRL_TYPE_MENU,
536 		.data_type	= UVC_CTRL_DATA_TYPE_BITMASK,
537 		.menu_info	= exposure_auto_controls,
538 		.menu_count	= ARRAY_SIZE(exposure_auto_controls),
539 		.slave_ids	= { V4L2_CID_EXPOSURE_ABSOLUTE, },
540 	},
541 	{
542 		.id		= V4L2_CID_EXPOSURE_AUTO_PRIORITY,
543 		.name		= "Exposure, Auto Priority",
544 		.entity		= UVC_GUID_UVC_CAMERA,
545 		.selector	= UVC_CT_AE_PRIORITY_CONTROL,
546 		.size		= 1,
547 		.offset		= 0,
548 		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
549 		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
550 	},
551 	{
552 		.id		= V4L2_CID_EXPOSURE_ABSOLUTE,
553 		.name		= "Exposure (Absolute)",
554 		.entity		= UVC_GUID_UVC_CAMERA,
555 		.selector	= UVC_CT_EXPOSURE_TIME_ABSOLUTE_CONTROL,
556 		.size		= 32,
557 		.offset		= 0,
558 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
559 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
560 		.master_id	= V4L2_CID_EXPOSURE_AUTO,
561 		.master_manual	= V4L2_EXPOSURE_MANUAL,
562 	},
563 	{
564 		.id		= V4L2_CID_AUTO_WHITE_BALANCE,
565 		.name		= "White Balance Temperature, Auto",
566 		.entity		= UVC_GUID_UVC_PROCESSING,
567 		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL,
568 		.size		= 1,
569 		.offset		= 0,
570 		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
571 		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
572 		.slave_ids	= { V4L2_CID_WHITE_BALANCE_TEMPERATURE, },
573 	},
574 	{
575 		.id		= V4L2_CID_WHITE_BALANCE_TEMPERATURE,
576 		.name		= "White Balance Temperature",
577 		.entity		= UVC_GUID_UVC_PROCESSING,
578 		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_CONTROL,
579 		.size		= 16,
580 		.offset		= 0,
581 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
582 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
583 		.master_id	= V4L2_CID_AUTO_WHITE_BALANCE,
584 		.master_manual	= 0,
585 	},
586 	{
587 		.id		= V4L2_CID_AUTO_WHITE_BALANCE,
588 		.name		= "White Balance Component, Auto",
589 		.entity		= UVC_GUID_UVC_PROCESSING,
590 		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL,
591 		.size		= 1,
592 		.offset		= 0,
593 		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
594 		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
595 		.slave_ids	= { V4L2_CID_BLUE_BALANCE,
596 				    V4L2_CID_RED_BALANCE },
597 	},
598 	{
599 		.id		= V4L2_CID_BLUE_BALANCE,
600 		.name		= "White Balance Blue Component",
601 		.entity		= UVC_GUID_UVC_PROCESSING,
602 		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_CONTROL,
603 		.size		= 16,
604 		.offset		= 0,
605 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
606 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
607 		.master_id	= V4L2_CID_AUTO_WHITE_BALANCE,
608 		.master_manual	= 0,
609 	},
610 	{
611 		.id		= V4L2_CID_RED_BALANCE,
612 		.name		= "White Balance Red Component",
613 		.entity		= UVC_GUID_UVC_PROCESSING,
614 		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_CONTROL,
615 		.size		= 16,
616 		.offset		= 16,
617 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
618 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
619 		.master_id	= V4L2_CID_AUTO_WHITE_BALANCE,
620 		.master_manual	= 0,
621 	},
622 	{
623 		.id		= V4L2_CID_FOCUS_ABSOLUTE,
624 		.name		= "Focus (absolute)",
625 		.entity		= UVC_GUID_UVC_CAMERA,
626 		.selector	= UVC_CT_FOCUS_ABSOLUTE_CONTROL,
627 		.size		= 16,
628 		.offset		= 0,
629 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
630 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
631 		.master_id	= V4L2_CID_FOCUS_AUTO,
632 		.master_manual	= 0,
633 	},
634 	{
635 		.id		= V4L2_CID_FOCUS_AUTO,
636 		.name		= "Focus, Auto",
637 		.entity		= UVC_GUID_UVC_CAMERA,
638 		.selector	= UVC_CT_FOCUS_AUTO_CONTROL,
639 		.size		= 1,
640 		.offset		= 0,
641 		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
642 		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
643 		.slave_ids	= { V4L2_CID_FOCUS_ABSOLUTE, },
644 	},
645 	{
646 		.id		= V4L2_CID_IRIS_ABSOLUTE,
647 		.name		= "Iris, Absolute",
648 		.entity		= UVC_GUID_UVC_CAMERA,
649 		.selector	= UVC_CT_IRIS_ABSOLUTE_CONTROL,
650 		.size		= 16,
651 		.offset		= 0,
652 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
653 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
654 	},
655 	{
656 		.id		= V4L2_CID_IRIS_RELATIVE,
657 		.name		= "Iris, Relative",
658 		.entity		= UVC_GUID_UVC_CAMERA,
659 		.selector	= UVC_CT_IRIS_RELATIVE_CONTROL,
660 		.size		= 8,
661 		.offset		= 0,
662 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
663 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
664 	},
665 	{
666 		.id		= V4L2_CID_ZOOM_ABSOLUTE,
667 		.name		= "Zoom, Absolute",
668 		.entity		= UVC_GUID_UVC_CAMERA,
669 		.selector	= UVC_CT_ZOOM_ABSOLUTE_CONTROL,
670 		.size		= 16,
671 		.offset		= 0,
672 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
673 		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
674 	},
675 	{
676 		.id		= V4L2_CID_ZOOM_CONTINUOUS,
677 		.name		= "Zoom, Continuous",
678 		.entity		= UVC_GUID_UVC_CAMERA,
679 		.selector	= UVC_CT_ZOOM_RELATIVE_CONTROL,
680 		.size		= 0,
681 		.offset		= 0,
682 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
683 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
684 		.get		= uvc_ctrl_get_zoom,
685 		.set		= uvc_ctrl_set_zoom,
686 	},
687 	{
688 		.id		= V4L2_CID_PAN_ABSOLUTE,
689 		.name		= "Pan (Absolute)",
690 		.entity		= UVC_GUID_UVC_CAMERA,
691 		.selector	= UVC_CT_PANTILT_ABSOLUTE_CONTROL,
692 		.size		= 32,
693 		.offset		= 0,
694 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
695 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
696 	},
697 	{
698 		.id		= V4L2_CID_TILT_ABSOLUTE,
699 		.name		= "Tilt (Absolute)",
700 		.entity		= UVC_GUID_UVC_CAMERA,
701 		.selector	= UVC_CT_PANTILT_ABSOLUTE_CONTROL,
702 		.size		= 32,
703 		.offset		= 32,
704 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
705 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
706 	},
707 	{
708 		.id		= V4L2_CID_PAN_SPEED,
709 		.name		= "Pan (Speed)",
710 		.entity		= UVC_GUID_UVC_CAMERA,
711 		.selector	= UVC_CT_PANTILT_RELATIVE_CONTROL,
712 		.size		= 16,
713 		.offset		= 0,
714 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
715 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
716 		.get		= uvc_ctrl_get_rel_speed,
717 		.set		= uvc_ctrl_set_rel_speed,
718 	},
719 	{
720 		.id		= V4L2_CID_TILT_SPEED,
721 		.name		= "Tilt (Speed)",
722 		.entity		= UVC_GUID_UVC_CAMERA,
723 		.selector	= UVC_CT_PANTILT_RELATIVE_CONTROL,
724 		.size		= 16,
725 		.offset		= 16,
726 		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
727 		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
728 		.get		= uvc_ctrl_get_rel_speed,
729 		.set		= uvc_ctrl_set_rel_speed,
730 	},
731 	{
732 		.id		= V4L2_CID_PRIVACY,
733 		.name		= "Privacy",
734 		.entity		= UVC_GUID_UVC_CAMERA,
735 		.selector	= UVC_CT_PRIVACY_CONTROL,
736 		.size		= 1,
737 		.offset		= 0,
738 		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
739 		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
740 	},
741 };
742 
743 /* ------------------------------------------------------------------------
744  * Utility functions
745  */
746 
747 static inline __u8 *uvc_ctrl_data(struct uvc_control *ctrl, int id)
748 {
749 	return ctrl->uvc_data + id * ctrl->info.size;
750 }
751 
752 static inline int uvc_test_bit(const __u8 *data, int bit)
753 {
754 	return (data[bit >> 3] >> (bit & 7)) & 1;
755 }
756 
757 static inline void uvc_clear_bit(__u8 *data, int bit)
758 {
759 	data[bit >> 3] &= ~(1 << (bit & 7));
760 }
761 
762 /* Extract the bit string specified by mapping->offset and mapping->size
763  * from the little-endian data stored at 'data' and return the result as
764  * a signed 32bit integer. Sign extension will be performed if the mapping
765  * references a signed data type.
766  */
767 static __s32 uvc_get_le_value(struct uvc_control_mapping *mapping,
768 	__u8 query, const __u8 *data)
769 {
770 	int bits = mapping->size;
771 	int offset = mapping->offset;
772 	__s32 value = 0;
773 	__u8 mask;
774 
775 	data += offset / 8;
776 	offset &= 7;
777 	mask = ((1LL << bits) - 1) << offset;
778 
779 	for (; bits > 0; data++) {
780 		__u8 byte = *data & mask;
781 		value |= offset > 0 ? (byte >> offset) : (byte << (-offset));
782 		bits -= 8 - (offset > 0 ? offset : 0);
783 		offset -= 8;
784 		mask = (1 << bits) - 1;
785 	}
786 
787 	/* Sign-extend the value if needed. */
788 	if (mapping->data_type == UVC_CTRL_DATA_TYPE_SIGNED)
789 		value |= -(value & (1 << (mapping->size - 1)));
790 
791 	return value;
792 }
793 
794 /* Set the bit string specified by mapping->offset and mapping->size
795  * in the little-endian data stored at 'data' to the value 'value'.
796  */
797 static void uvc_set_le_value(struct uvc_control_mapping *mapping,
798 	__s32 value, __u8 *data)
799 {
800 	int bits = mapping->size;
801 	int offset = mapping->offset;
802 	__u8 mask;
803 
804 	/* According to the v4l2 spec, writing any value to a button control
805 	 * should result in the action belonging to the button control being
806 	 * triggered. UVC devices however want to see a 1 written -> override
807 	 * value.
808 	 */
809 	if (mapping->v4l2_type == V4L2_CTRL_TYPE_BUTTON)
810 		value = -1;
811 
812 	data += offset / 8;
813 	offset &= 7;
814 
815 	for (; bits > 0; data++) {
816 		mask = ((1LL << bits) - 1) << offset;
817 		*data = (*data & ~mask) | ((value << offset) & mask);
818 		value >>= offset ? offset : 8;
819 		bits -= 8 - offset;
820 		offset = 0;
821 	}
822 }
823 
824 /* ------------------------------------------------------------------------
825  * Terminal and unit management
826  */
827 
828 static const __u8 uvc_processing_guid[16] = UVC_GUID_UVC_PROCESSING;
829 static const __u8 uvc_camera_guid[16] = UVC_GUID_UVC_CAMERA;
830 static const __u8 uvc_media_transport_input_guid[16] =
831 	UVC_GUID_UVC_MEDIA_TRANSPORT_INPUT;
832 
833 static int uvc_entity_match_guid(const struct uvc_entity *entity,
834 	const __u8 guid[16])
835 {
836 	switch (UVC_ENTITY_TYPE(entity)) {
837 	case UVC_ITT_CAMERA:
838 		return memcmp(uvc_camera_guid, guid, 16) == 0;
839 
840 	case UVC_ITT_MEDIA_TRANSPORT_INPUT:
841 		return memcmp(uvc_media_transport_input_guid, guid, 16) == 0;
842 
843 	case UVC_VC_PROCESSING_UNIT:
844 		return memcmp(uvc_processing_guid, guid, 16) == 0;
845 
846 	case UVC_VC_EXTENSION_UNIT:
847 		return memcmp(entity->extension.guidExtensionCode,
848 			      guid, 16) == 0;
849 
850 	default:
851 		return 0;
852 	}
853 }
854 
855 /* ------------------------------------------------------------------------
856  * UVC Controls
857  */
858 
859 static void __uvc_find_control(struct uvc_entity *entity, __u32 v4l2_id,
860 	struct uvc_control_mapping **mapping, struct uvc_control **control,
861 	int next)
862 {
863 	struct uvc_control *ctrl;
864 	struct uvc_control_mapping *map;
865 	unsigned int i;
866 
867 	if (entity == NULL)
868 		return;
869 
870 	for (i = 0; i < entity->ncontrols; ++i) {
871 		ctrl = &entity->controls[i];
872 		if (!ctrl->initialized)
873 			continue;
874 
875 		list_for_each_entry(map, &ctrl->info.mappings, list) {
876 			if ((map->id == v4l2_id) && !next) {
877 				*control = ctrl;
878 				*mapping = map;
879 				return;
880 			}
881 
882 			if ((*mapping == NULL || (*mapping)->id > map->id) &&
883 			    (map->id > v4l2_id) && next) {
884 				*control = ctrl;
885 				*mapping = map;
886 			}
887 		}
888 	}
889 }
890 
891 static struct uvc_control *uvc_find_control(struct uvc_video_chain *chain,
892 	__u32 v4l2_id, struct uvc_control_mapping **mapping)
893 {
894 	struct uvc_control *ctrl = NULL;
895 	struct uvc_entity *entity;
896 	int next = v4l2_id & V4L2_CTRL_FLAG_NEXT_CTRL;
897 
898 	*mapping = NULL;
899 
900 	/* Mask the query flags. */
901 	v4l2_id &= V4L2_CTRL_ID_MASK;
902 
903 	/* Find the control. */
904 	list_for_each_entry(entity, &chain->entities, chain) {
905 		__uvc_find_control(entity, v4l2_id, mapping, &ctrl, next);
906 		if (ctrl && !next)
907 			return ctrl;
908 	}
909 
910 	if (ctrl == NULL && !next)
911 		uvc_trace(UVC_TRACE_CONTROL, "Control 0x%08x not found.\n",
912 				v4l2_id);
913 
914 	return ctrl;
915 }
916 
917 static int uvc_ctrl_populate_cache(struct uvc_video_chain *chain,
918 	struct uvc_control *ctrl)
919 {
920 	int ret;
921 
922 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_DEF) {
923 		ret = uvc_query_ctrl(chain->dev, UVC_GET_DEF, ctrl->entity->id,
924 				     chain->dev->intfnum, ctrl->info.selector,
925 				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_DEF),
926 				     ctrl->info.size);
927 		if (ret < 0)
928 			return ret;
929 	}
930 
931 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN) {
932 		ret = uvc_query_ctrl(chain->dev, UVC_GET_MIN, ctrl->entity->id,
933 				     chain->dev->intfnum, ctrl->info.selector,
934 				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MIN),
935 				     ctrl->info.size);
936 		if (ret < 0)
937 			return ret;
938 	}
939 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX) {
940 		ret = uvc_query_ctrl(chain->dev, UVC_GET_MAX, ctrl->entity->id,
941 				     chain->dev->intfnum, ctrl->info.selector,
942 				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MAX),
943 				     ctrl->info.size);
944 		if (ret < 0)
945 			return ret;
946 	}
947 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES) {
948 		ret = uvc_query_ctrl(chain->dev, UVC_GET_RES, ctrl->entity->id,
949 				     chain->dev->intfnum, ctrl->info.selector,
950 				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES),
951 				     ctrl->info.size);
952 		if (ret < 0) {
953 			if (UVC_ENTITY_TYPE(ctrl->entity) !=
954 			    UVC_VC_EXTENSION_UNIT)
955 				return ret;
956 
957 			/* GET_RES is mandatory for XU controls, but some
958 			 * cameras still choke on it. Ignore errors and set the
959 			 * resolution value to zero.
960 			 */
961 			uvc_warn_once(chain->dev, UVC_WARN_XU_GET_RES,
962 				      "UVC non compliance - GET_RES failed on "
963 				      "an XU control. Enabling workaround.\n");
964 			memset(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES), 0,
965 			       ctrl->info.size);
966 		}
967 	}
968 
969 	ctrl->cached = 1;
970 	return 0;
971 }
972 
973 static int __uvc_ctrl_get(struct uvc_video_chain *chain,
974 	struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
975 	s32 *value)
976 {
977 	struct uvc_menu_info *menu;
978 	unsigned int i;
979 	int ret;
980 
981 	if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
982 		return -EACCES;
983 
984 	if (!ctrl->loaded) {
985 		ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, ctrl->entity->id,
986 				chain->dev->intfnum, ctrl->info.selector,
987 				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
988 				ctrl->info.size);
989 		if (ret < 0)
990 			return ret;
991 
992 		ctrl->loaded = 1;
993 	}
994 
995 	*value = mapping->get(mapping, UVC_GET_CUR,
996 		uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
997 
998 	if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
999 		menu = mapping->menu_info;
1000 		for (i = 0; i < mapping->menu_count; ++i, ++menu) {
1001 			if (menu->value == *value) {
1002 				*value = i;
1003 				break;
1004 			}
1005 		}
1006 	}
1007 
1008 	return 0;
1009 }
1010 
1011 static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
1012 	struct uvc_control *ctrl,
1013 	struct uvc_control_mapping *mapping,
1014 	struct v4l2_queryctrl *v4l2_ctrl)
1015 {
1016 	struct uvc_control_mapping *master_map = NULL;
1017 	struct uvc_control *master_ctrl = NULL;
1018 	struct uvc_menu_info *menu;
1019 	unsigned int i;
1020 
1021 	memset(v4l2_ctrl, 0, sizeof *v4l2_ctrl);
1022 	v4l2_ctrl->id = mapping->id;
1023 	v4l2_ctrl->type = mapping->v4l2_type;
1024 	strlcpy(v4l2_ctrl->name, mapping->name, sizeof v4l2_ctrl->name);
1025 	v4l2_ctrl->flags = 0;
1026 
1027 	if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
1028 		v4l2_ctrl->flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
1029 	if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
1030 		v4l2_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
1031 
1032 	if (mapping->master_id)
1033 		__uvc_find_control(ctrl->entity, mapping->master_id,
1034 				   &master_map, &master_ctrl, 0);
1035 	if (master_ctrl && (master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR)) {
1036 		s32 val;
1037 		int ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
1038 		if (ret < 0)
1039 			return ret;
1040 
1041 		if (val != mapping->master_manual)
1042 				v4l2_ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
1043 	}
1044 
1045 	if (!ctrl->cached) {
1046 		int ret = uvc_ctrl_populate_cache(chain, ctrl);
1047 		if (ret < 0)
1048 			return ret;
1049 	}
1050 
1051 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_DEF) {
1052 		v4l2_ctrl->default_value = mapping->get(mapping, UVC_GET_DEF,
1053 				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_DEF));
1054 	}
1055 
1056 	switch (mapping->v4l2_type) {
1057 	case V4L2_CTRL_TYPE_MENU:
1058 		v4l2_ctrl->minimum = 0;
1059 		v4l2_ctrl->maximum = mapping->menu_count - 1;
1060 		v4l2_ctrl->step = 1;
1061 
1062 		menu = mapping->menu_info;
1063 		for (i = 0; i < mapping->menu_count; ++i, ++menu) {
1064 			if (menu->value == v4l2_ctrl->default_value) {
1065 				v4l2_ctrl->default_value = i;
1066 				break;
1067 			}
1068 		}
1069 
1070 		return 0;
1071 
1072 	case V4L2_CTRL_TYPE_BOOLEAN:
1073 		v4l2_ctrl->minimum = 0;
1074 		v4l2_ctrl->maximum = 1;
1075 		v4l2_ctrl->step = 1;
1076 		return 0;
1077 
1078 	case V4L2_CTRL_TYPE_BUTTON:
1079 		v4l2_ctrl->minimum = 0;
1080 		v4l2_ctrl->maximum = 0;
1081 		v4l2_ctrl->step = 0;
1082 		return 0;
1083 
1084 	default:
1085 		break;
1086 	}
1087 
1088 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN)
1089 		v4l2_ctrl->minimum = mapping->get(mapping, UVC_GET_MIN,
1090 				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MIN));
1091 
1092 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX)
1093 		v4l2_ctrl->maximum = mapping->get(mapping, UVC_GET_MAX,
1094 				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MAX));
1095 
1096 	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES)
1097 		v4l2_ctrl->step = mapping->get(mapping, UVC_GET_RES,
1098 				  uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
1099 
1100 	return 0;
1101 }
1102 
1103 int uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
1104 	struct v4l2_queryctrl *v4l2_ctrl)
1105 {
1106 	struct uvc_control *ctrl;
1107 	struct uvc_control_mapping *mapping;
1108 	int ret;
1109 
1110 	ret = mutex_lock_interruptible(&chain->ctrl_mutex);
1111 	if (ret < 0)
1112 		return -ERESTARTSYS;
1113 
1114 	ctrl = uvc_find_control(chain, v4l2_ctrl->id, &mapping);
1115 	if (ctrl == NULL) {
1116 		ret = -EINVAL;
1117 		goto done;
1118 	}
1119 
1120 	ret = __uvc_query_v4l2_ctrl(chain, ctrl, mapping, v4l2_ctrl);
1121 done:
1122 	mutex_unlock(&chain->ctrl_mutex);
1123 	return ret;
1124 }
1125 
1126 /*
1127  * Mapping V4L2 controls to UVC controls can be straighforward if done well.
1128  * Most of the UVC controls exist in V4L2, and can be mapped directly. Some
1129  * must be grouped (for instance the Red Balance, Blue Balance and Do White
1130  * Balance V4L2 controls use the White Balance Component UVC control) or
1131  * otherwise translated. The approach we take here is to use a translation
1132  * table for the controls that can be mapped directly, and handle the others
1133  * manually.
1134  */
1135 int uvc_query_v4l2_menu(struct uvc_video_chain *chain,
1136 	struct v4l2_querymenu *query_menu)
1137 {
1138 	struct uvc_menu_info *menu_info;
1139 	struct uvc_control_mapping *mapping;
1140 	struct uvc_control *ctrl;
1141 	u32 index = query_menu->index;
1142 	u32 id = query_menu->id;
1143 	int ret;
1144 
1145 	memset(query_menu, 0, sizeof(*query_menu));
1146 	query_menu->id = id;
1147 	query_menu->index = index;
1148 
1149 	ret = mutex_lock_interruptible(&chain->ctrl_mutex);
1150 	if (ret < 0)
1151 		return -ERESTARTSYS;
1152 
1153 	ctrl = uvc_find_control(chain, query_menu->id, &mapping);
1154 	if (ctrl == NULL || mapping->v4l2_type != V4L2_CTRL_TYPE_MENU) {
1155 		ret = -EINVAL;
1156 		goto done;
1157 	}
1158 
1159 	if (query_menu->index >= mapping->menu_count) {
1160 		ret = -EINVAL;
1161 		goto done;
1162 	}
1163 
1164 	menu_info = &mapping->menu_info[query_menu->index];
1165 
1166 	if (mapping->data_type == UVC_CTRL_DATA_TYPE_BITMASK &&
1167 	    (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES)) {
1168 		s32 bitmap;
1169 
1170 		if (!ctrl->cached) {
1171 			ret = uvc_ctrl_populate_cache(chain, ctrl);
1172 			if (ret < 0)
1173 				goto done;
1174 		}
1175 
1176 		bitmap = mapping->get(mapping, UVC_GET_RES,
1177 				      uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
1178 		if (!(bitmap & menu_info->value)) {
1179 			ret = -EINVAL;
1180 			goto done;
1181 		}
1182 	}
1183 
1184 	strlcpy(query_menu->name, menu_info->name, sizeof query_menu->name);
1185 
1186 done:
1187 	mutex_unlock(&chain->ctrl_mutex);
1188 	return ret;
1189 }
1190 
1191 /* --------------------------------------------------------------------------
1192  * Ctrl event handling
1193  */
1194 
1195 static void uvc_ctrl_fill_event(struct uvc_video_chain *chain,
1196 	struct v4l2_event *ev,
1197 	struct uvc_control *ctrl,
1198 	struct uvc_control_mapping *mapping,
1199 	s32 value, u32 changes)
1200 {
1201 	struct v4l2_queryctrl v4l2_ctrl;
1202 
1203 	__uvc_query_v4l2_ctrl(chain, ctrl, mapping, &v4l2_ctrl);
1204 
1205 	memset(ev->reserved, 0, sizeof(ev->reserved));
1206 	ev->type = V4L2_EVENT_CTRL;
1207 	ev->id = v4l2_ctrl.id;
1208 	ev->u.ctrl.value = value;
1209 	ev->u.ctrl.changes = changes;
1210 	ev->u.ctrl.type = v4l2_ctrl.type;
1211 	ev->u.ctrl.flags = v4l2_ctrl.flags;
1212 	ev->u.ctrl.minimum = v4l2_ctrl.minimum;
1213 	ev->u.ctrl.maximum = v4l2_ctrl.maximum;
1214 	ev->u.ctrl.step = v4l2_ctrl.step;
1215 	ev->u.ctrl.default_value = v4l2_ctrl.default_value;
1216 }
1217 
1218 static void uvc_ctrl_send_event(struct uvc_fh *handle,
1219 	struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
1220 	s32 value, u32 changes)
1221 {
1222 	struct v4l2_subscribed_event *sev;
1223 	struct v4l2_event ev;
1224 
1225 	if (list_empty(&mapping->ev_subs))
1226 		return;
1227 
1228 	uvc_ctrl_fill_event(handle->chain, &ev, ctrl, mapping, value, changes);
1229 
1230 	list_for_each_entry(sev, &mapping->ev_subs, node) {
1231 		if (sev->fh && (sev->fh != &handle->vfh ||
1232 		    (sev->flags & V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK) ||
1233 		    (changes & V4L2_EVENT_CTRL_CH_FLAGS)))
1234 			v4l2_event_queue_fh(sev->fh, &ev);
1235 	}
1236 }
1237 
1238 static void uvc_ctrl_send_slave_event(struct uvc_fh *handle,
1239 	struct uvc_control *master, u32 slave_id,
1240 	const struct v4l2_ext_control *xctrls, unsigned int xctrls_count)
1241 {
1242 	struct uvc_control_mapping *mapping = NULL;
1243 	struct uvc_control *ctrl = NULL;
1244 	u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
1245 	unsigned int i;
1246 	s32 val = 0;
1247 
1248 	/*
1249 	 * We can skip sending an event for the slave if the slave
1250 	 * is being modified in the same transaction.
1251 	 */
1252 	for (i = 0; i < xctrls_count; i++) {
1253 		if (xctrls[i].id == slave_id)
1254 			return;
1255 	}
1256 
1257 	__uvc_find_control(master->entity, slave_id, &mapping, &ctrl, 0);
1258 	if (ctrl == NULL)
1259 		return;
1260 
1261 	if (__uvc_ctrl_get(handle->chain, ctrl, mapping, &val) == 0)
1262 		changes |= V4L2_EVENT_CTRL_CH_VALUE;
1263 
1264 	uvc_ctrl_send_event(handle, ctrl, mapping, val, changes);
1265 }
1266 
1267 static void uvc_ctrl_send_events(struct uvc_fh *handle,
1268 	const struct v4l2_ext_control *xctrls, unsigned int xctrls_count)
1269 {
1270 	struct uvc_control_mapping *mapping;
1271 	struct uvc_control *ctrl;
1272 	u32 changes = V4L2_EVENT_CTRL_CH_VALUE;
1273 	unsigned int i;
1274 	unsigned int j;
1275 
1276 	for (i = 0; i < xctrls_count; ++i) {
1277 		ctrl = uvc_find_control(handle->chain, xctrls[i].id, &mapping);
1278 
1279 		for (j = 0; j < ARRAY_SIZE(mapping->slave_ids); ++j) {
1280 			if (!mapping->slave_ids[j])
1281 				break;
1282 			uvc_ctrl_send_slave_event(handle, ctrl,
1283 						  mapping->slave_ids[j],
1284 						  xctrls, xctrls_count);
1285 		}
1286 
1287 		/*
1288 		 * If the master is being modified in the same transaction
1289 		 * flags may change too.
1290 		 */
1291 		if (mapping->master_id) {
1292 			for (j = 0; j < xctrls_count; j++) {
1293 				if (xctrls[j].id == mapping->master_id) {
1294 					changes |= V4L2_EVENT_CTRL_CH_FLAGS;
1295 					break;
1296 				}
1297 			}
1298 		}
1299 
1300 		uvc_ctrl_send_event(handle, ctrl, mapping, xctrls[i].value,
1301 				    changes);
1302 	}
1303 }
1304 
1305 static int uvc_ctrl_add_event(struct v4l2_subscribed_event *sev, unsigned elems)
1306 {
1307 	struct uvc_fh *handle = container_of(sev->fh, struct uvc_fh, vfh);
1308 	struct uvc_control_mapping *mapping;
1309 	struct uvc_control *ctrl;
1310 	int ret;
1311 
1312 	ret = mutex_lock_interruptible(&handle->chain->ctrl_mutex);
1313 	if (ret < 0)
1314 		return -ERESTARTSYS;
1315 
1316 	ctrl = uvc_find_control(handle->chain, sev->id, &mapping);
1317 	if (ctrl == NULL) {
1318 		ret = -EINVAL;
1319 		goto done;
1320 	}
1321 
1322 	list_add_tail(&sev->node, &mapping->ev_subs);
1323 	if (sev->flags & V4L2_EVENT_SUB_FL_SEND_INITIAL) {
1324 		struct v4l2_event ev;
1325 		u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
1326 		s32 val = 0;
1327 
1328 		if (__uvc_ctrl_get(handle->chain, ctrl, mapping, &val) == 0)
1329 			changes |= V4L2_EVENT_CTRL_CH_VALUE;
1330 
1331 		uvc_ctrl_fill_event(handle->chain, &ev, ctrl, mapping, val,
1332 				    changes);
1333 		/* Mark the queue as active, allowing this initial
1334 		   event to be accepted. */
1335 		sev->elems = elems;
1336 		v4l2_event_queue_fh(sev->fh, &ev);
1337 	}
1338 
1339 done:
1340 	mutex_unlock(&handle->chain->ctrl_mutex);
1341 	return ret;
1342 }
1343 
1344 static void uvc_ctrl_del_event(struct v4l2_subscribed_event *sev)
1345 {
1346 	struct uvc_fh *handle = container_of(sev->fh, struct uvc_fh, vfh);
1347 
1348 	mutex_lock(&handle->chain->ctrl_mutex);
1349 	list_del(&sev->node);
1350 	mutex_unlock(&handle->chain->ctrl_mutex);
1351 }
1352 
1353 const struct v4l2_subscribed_event_ops uvc_ctrl_sub_ev_ops = {
1354 	.add = uvc_ctrl_add_event,
1355 	.del = uvc_ctrl_del_event,
1356 	.replace = v4l2_ctrl_replace,
1357 	.merge = v4l2_ctrl_merge,
1358 };
1359 
1360 /* --------------------------------------------------------------------------
1361  * Control transactions
1362  *
1363  * To make extended set operations as atomic as the hardware allows, controls
1364  * are handled using begin/commit/rollback operations.
1365  *
1366  * At the beginning of a set request, uvc_ctrl_begin should be called to
1367  * initialize the request. This function acquires the control lock.
1368  *
1369  * When setting a control, the new value is stored in the control data field
1370  * at position UVC_CTRL_DATA_CURRENT. The control is then marked as dirty for
1371  * later processing. If the UVC and V4L2 control sizes differ, the current
1372  * value is loaded from the hardware before storing the new value in the data
1373  * field.
1374  *
1375  * After processing all controls in the transaction, uvc_ctrl_commit or
1376  * uvc_ctrl_rollback must be called to apply the pending changes to the
1377  * hardware or revert them. When applying changes, all controls marked as
1378  * dirty will be modified in the UVC device, and the dirty flag will be
1379  * cleared. When reverting controls, the control data field
1380  * UVC_CTRL_DATA_CURRENT is reverted to its previous value
1381  * (UVC_CTRL_DATA_BACKUP) for all dirty controls. Both functions release the
1382  * control lock.
1383  */
1384 int uvc_ctrl_begin(struct uvc_video_chain *chain)
1385 {
1386 	return mutex_lock_interruptible(&chain->ctrl_mutex) ? -ERESTARTSYS : 0;
1387 }
1388 
1389 static int uvc_ctrl_commit_entity(struct uvc_device *dev,
1390 	struct uvc_entity *entity, int rollback)
1391 {
1392 	struct uvc_control *ctrl;
1393 	unsigned int i;
1394 	int ret;
1395 
1396 	if (entity == NULL)
1397 		return 0;
1398 
1399 	for (i = 0; i < entity->ncontrols; ++i) {
1400 		ctrl = &entity->controls[i];
1401 		if (!ctrl->initialized)
1402 			continue;
1403 
1404 		/* Reset the loaded flag for auto-update controls that were
1405 		 * marked as loaded in uvc_ctrl_get/uvc_ctrl_set to prevent
1406 		 * uvc_ctrl_get from using the cached value, and for write-only
1407 		 * controls to prevent uvc_ctrl_set from setting bits not
1408 		 * explicitly set by the user.
1409 		 */
1410 		if (ctrl->info.flags & UVC_CTRL_FLAG_AUTO_UPDATE ||
1411 		    !(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
1412 			ctrl->loaded = 0;
1413 
1414 		if (!ctrl->dirty)
1415 			continue;
1416 
1417 		if (!rollback)
1418 			ret = uvc_query_ctrl(dev, UVC_SET_CUR, ctrl->entity->id,
1419 				dev->intfnum, ctrl->info.selector,
1420 				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
1421 				ctrl->info.size);
1422 		else
1423 			ret = 0;
1424 
1425 		if (rollback || ret < 0)
1426 			memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
1427 			       uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
1428 			       ctrl->info.size);
1429 
1430 		ctrl->dirty = 0;
1431 
1432 		if (ret < 0)
1433 			return ret;
1434 	}
1435 
1436 	return 0;
1437 }
1438 
1439 int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
1440 		      const struct v4l2_ext_control *xctrls,
1441 		      unsigned int xctrls_count)
1442 {
1443 	struct uvc_video_chain *chain = handle->chain;
1444 	struct uvc_entity *entity;
1445 	int ret = 0;
1446 
1447 	/* Find the control. */
1448 	list_for_each_entry(entity, &chain->entities, chain) {
1449 		ret = uvc_ctrl_commit_entity(chain->dev, entity, rollback);
1450 		if (ret < 0)
1451 			goto done;
1452 	}
1453 
1454 	if (!rollback)
1455 		uvc_ctrl_send_events(handle, xctrls, xctrls_count);
1456 done:
1457 	mutex_unlock(&chain->ctrl_mutex);
1458 	return ret;
1459 }
1460 
1461 int uvc_ctrl_get(struct uvc_video_chain *chain,
1462 	struct v4l2_ext_control *xctrl)
1463 {
1464 	struct uvc_control *ctrl;
1465 	struct uvc_control_mapping *mapping;
1466 
1467 	ctrl = uvc_find_control(chain, xctrl->id, &mapping);
1468 	if (ctrl == NULL)
1469 		return -EINVAL;
1470 
1471 	return __uvc_ctrl_get(chain, ctrl, mapping, &xctrl->value);
1472 }
1473 
1474 int uvc_ctrl_set(struct uvc_video_chain *chain,
1475 	struct v4l2_ext_control *xctrl)
1476 {
1477 	struct uvc_control *ctrl;
1478 	struct uvc_control_mapping *mapping;
1479 	s32 value;
1480 	u32 step;
1481 	s32 min;
1482 	s32 max;
1483 	int ret;
1484 
1485 	ctrl = uvc_find_control(chain, xctrl->id, &mapping);
1486 	if (ctrl == NULL)
1487 		return -EINVAL;
1488 	if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
1489 		return -EACCES;
1490 
1491 	/* Clamp out of range values. */
1492 	switch (mapping->v4l2_type) {
1493 	case V4L2_CTRL_TYPE_INTEGER:
1494 		if (!ctrl->cached) {
1495 			ret = uvc_ctrl_populate_cache(chain, ctrl);
1496 			if (ret < 0)
1497 				return ret;
1498 		}
1499 
1500 		min = mapping->get(mapping, UVC_GET_MIN,
1501 				   uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MIN));
1502 		max = mapping->get(mapping, UVC_GET_MAX,
1503 				   uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MAX));
1504 		step = mapping->get(mapping, UVC_GET_RES,
1505 				    uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
1506 		if (step == 0)
1507 			step = 1;
1508 
1509 		xctrl->value = min + ((u32)(xctrl->value - min) + step / 2)
1510 			     / step * step;
1511 		if (mapping->data_type == UVC_CTRL_DATA_TYPE_SIGNED)
1512 			xctrl->value = clamp(xctrl->value, min, max);
1513 		else
1514 			xctrl->value = clamp_t(u32, xctrl->value, min, max);
1515 		value = xctrl->value;
1516 		break;
1517 
1518 	case V4L2_CTRL_TYPE_BOOLEAN:
1519 		xctrl->value = clamp(xctrl->value, 0, 1);
1520 		value = xctrl->value;
1521 		break;
1522 
1523 	case V4L2_CTRL_TYPE_MENU:
1524 		if (xctrl->value < 0 || xctrl->value >= mapping->menu_count)
1525 			return -ERANGE;
1526 		value = mapping->menu_info[xctrl->value].value;
1527 
1528 		/* Valid menu indices are reported by the GET_RES request for
1529 		 * UVC controls that support it.
1530 		 */
1531 		if (mapping->data_type == UVC_CTRL_DATA_TYPE_BITMASK &&
1532 		    (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES)) {
1533 			if (!ctrl->cached) {
1534 				ret = uvc_ctrl_populate_cache(chain, ctrl);
1535 				if (ret < 0)
1536 					return ret;
1537 			}
1538 
1539 			step = mapping->get(mapping, UVC_GET_RES,
1540 					uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
1541 			if (!(step & value))
1542 				return -EINVAL;
1543 		}
1544 
1545 		break;
1546 
1547 	default:
1548 		value = xctrl->value;
1549 		break;
1550 	}
1551 
1552 	/* If the mapping doesn't span the whole UVC control, the current value
1553 	 * needs to be loaded from the device to perform the read-modify-write
1554 	 * operation.
1555 	 */
1556 	if (!ctrl->loaded && (ctrl->info.size * 8) != mapping->size) {
1557 		if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0) {
1558 			memset(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
1559 				0, ctrl->info.size);
1560 		} else {
1561 			ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
1562 				ctrl->entity->id, chain->dev->intfnum,
1563 				ctrl->info.selector,
1564 				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
1565 				ctrl->info.size);
1566 			if (ret < 0)
1567 				return ret;
1568 		}
1569 
1570 		ctrl->loaded = 1;
1571 	}
1572 
1573 	/* Backup the current value in case we need to rollback later. */
1574 	if (!ctrl->dirty) {
1575 		memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
1576 		       uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
1577 		       ctrl->info.size);
1578 	}
1579 
1580 	mapping->set(mapping, value,
1581 		uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
1582 
1583 	ctrl->dirty = 1;
1584 	ctrl->modified = 1;
1585 	return 0;
1586 }
1587 
1588 /* --------------------------------------------------------------------------
1589  * Dynamic controls
1590  */
1591 
1592 static void uvc_ctrl_fixup_xu_info(struct uvc_device *dev,
1593 	const struct uvc_control *ctrl, struct uvc_control_info *info)
1594 {
1595 	struct uvc_ctrl_fixup {
1596 		struct usb_device_id id;
1597 		u8 entity;
1598 		u8 selector;
1599 		u8 flags;
1600 	};
1601 
1602 	static const struct uvc_ctrl_fixup fixups[] = {
1603 		{ { USB_DEVICE(0x046d, 0x08c2) }, 9, 1,
1604 			UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX |
1605 			UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_SET_CUR |
1606 			UVC_CTRL_FLAG_AUTO_UPDATE },
1607 		{ { USB_DEVICE(0x046d, 0x08cc) }, 9, 1,
1608 			UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX |
1609 			UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_SET_CUR |
1610 			UVC_CTRL_FLAG_AUTO_UPDATE },
1611 		{ { USB_DEVICE(0x046d, 0x0994) }, 9, 1,
1612 			UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX |
1613 			UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_SET_CUR |
1614 			UVC_CTRL_FLAG_AUTO_UPDATE },
1615 	};
1616 
1617 	unsigned int i;
1618 
1619 	for (i = 0; i < ARRAY_SIZE(fixups); ++i) {
1620 		if (!usb_match_one_id(dev->intf, &fixups[i].id))
1621 			continue;
1622 
1623 		if (fixups[i].entity == ctrl->entity->id &&
1624 		    fixups[i].selector == info->selector) {
1625 			info->flags = fixups[i].flags;
1626 			return;
1627 		}
1628 	}
1629 }
1630 
1631 /*
1632  * Query control information (size and flags) for XU controls.
1633  */
1634 static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,
1635 	const struct uvc_control *ctrl, struct uvc_control_info *info)
1636 {
1637 	u8 *data;
1638 	int ret;
1639 
1640 	data = kmalloc(2, GFP_KERNEL);
1641 	if (data == NULL)
1642 		return -ENOMEM;
1643 
1644 	memcpy(info->entity, ctrl->entity->extension.guidExtensionCode,
1645 	       sizeof(info->entity));
1646 	info->index = ctrl->index;
1647 	info->selector = ctrl->index + 1;
1648 
1649 	/* Query and verify the control length (GET_LEN) */
1650 	ret = uvc_query_ctrl(dev, UVC_GET_LEN, ctrl->entity->id, dev->intfnum,
1651 			     info->selector, data, 2);
1652 	if (ret < 0) {
1653 		uvc_trace(UVC_TRACE_CONTROL,
1654 			  "GET_LEN failed on control %pUl/%u (%d).\n",
1655 			   info->entity, info->selector, ret);
1656 		goto done;
1657 	}
1658 
1659 	info->size = le16_to_cpup((__le16 *)data);
1660 
1661 	/* Query the control information (GET_INFO) */
1662 	ret = uvc_query_ctrl(dev, UVC_GET_INFO, ctrl->entity->id, dev->intfnum,
1663 			     info->selector, data, 1);
1664 	if (ret < 0) {
1665 		uvc_trace(UVC_TRACE_CONTROL,
1666 			  "GET_INFO failed on control %pUl/%u (%d).\n",
1667 			  info->entity, info->selector, ret);
1668 		goto done;
1669 	}
1670 
1671 	info->flags = UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX
1672 		    | UVC_CTRL_FLAG_GET_RES | UVC_CTRL_FLAG_GET_DEF
1673 		    | (data[0] & UVC_CONTROL_CAP_GET ?
1674 		       UVC_CTRL_FLAG_GET_CUR : 0)
1675 		    | (data[0] & UVC_CONTROL_CAP_SET ?
1676 		       UVC_CTRL_FLAG_SET_CUR : 0)
1677 		    | (data[0] & UVC_CONTROL_CAP_AUTOUPDATE ?
1678 		       UVC_CTRL_FLAG_AUTO_UPDATE : 0);
1679 
1680 	uvc_ctrl_fixup_xu_info(dev, ctrl, info);
1681 
1682 	uvc_trace(UVC_TRACE_CONTROL, "XU control %pUl/%u queried: len %u, "
1683 		  "flags { get %u set %u auto %u }.\n",
1684 		  info->entity, info->selector, info->size,
1685 		  (info->flags & UVC_CTRL_FLAG_GET_CUR) ? 1 : 0,
1686 		  (info->flags & UVC_CTRL_FLAG_SET_CUR) ? 1 : 0,
1687 		  (info->flags & UVC_CTRL_FLAG_AUTO_UPDATE) ? 1 : 0);
1688 
1689 done:
1690 	kfree(data);
1691 	return ret;
1692 }
1693 
1694 static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
1695 	const struct uvc_control_info *info);
1696 
1697 static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
1698 	struct uvc_control *ctrl)
1699 {
1700 	struct uvc_control_info info;
1701 	int ret;
1702 
1703 	if (ctrl->initialized)
1704 		return 0;
1705 
1706 	ret = uvc_ctrl_fill_xu_info(dev, ctrl, &info);
1707 	if (ret < 0)
1708 		return ret;
1709 
1710 	ret = uvc_ctrl_add_info(dev, ctrl, &info);
1711 	if (ret < 0)
1712 		uvc_trace(UVC_TRACE_CONTROL, "Failed to initialize control "
1713 			  "%pUl/%u on device %s entity %u\n", info.entity,
1714 			  info.selector, dev->udev->devpath, ctrl->entity->id);
1715 
1716 	return ret;
1717 }
1718 
1719 int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
1720 	struct uvc_xu_control_query *xqry)
1721 {
1722 	struct uvc_entity *entity;
1723 	struct uvc_control *ctrl;
1724 	unsigned int i, found = 0;
1725 	__u32 reqflags;
1726 	__u16 size;
1727 	__u8 *data = NULL;
1728 	int ret;
1729 
1730 	/* Find the extension unit. */
1731 	list_for_each_entry(entity, &chain->entities, chain) {
1732 		if (UVC_ENTITY_TYPE(entity) == UVC_VC_EXTENSION_UNIT &&
1733 		    entity->id == xqry->unit)
1734 			break;
1735 	}
1736 
1737 	if (entity->id != xqry->unit) {
1738 		uvc_trace(UVC_TRACE_CONTROL, "Extension unit %u not found.\n",
1739 			xqry->unit);
1740 		return -ENOENT;
1741 	}
1742 
1743 	/* Find the control and perform delayed initialization if needed. */
1744 	for (i = 0; i < entity->ncontrols; ++i) {
1745 		ctrl = &entity->controls[i];
1746 		if (ctrl->index == xqry->selector - 1) {
1747 			found = 1;
1748 			break;
1749 		}
1750 	}
1751 
1752 	if (!found) {
1753 		uvc_trace(UVC_TRACE_CONTROL, "Control %pUl/%u not found.\n",
1754 			entity->extension.guidExtensionCode, xqry->selector);
1755 		return -ENOENT;
1756 	}
1757 
1758 	if (mutex_lock_interruptible(&chain->ctrl_mutex))
1759 		return -ERESTARTSYS;
1760 
1761 	ret = uvc_ctrl_init_xu_ctrl(chain->dev, ctrl);
1762 	if (ret < 0) {
1763 		ret = -ENOENT;
1764 		goto done;
1765 	}
1766 
1767 	/* Validate the required buffer size and flags for the request */
1768 	reqflags = 0;
1769 	size = ctrl->info.size;
1770 
1771 	switch (xqry->query) {
1772 	case UVC_GET_CUR:
1773 		reqflags = UVC_CTRL_FLAG_GET_CUR;
1774 		break;
1775 	case UVC_GET_MIN:
1776 		reqflags = UVC_CTRL_FLAG_GET_MIN;
1777 		break;
1778 	case UVC_GET_MAX:
1779 		reqflags = UVC_CTRL_FLAG_GET_MAX;
1780 		break;
1781 	case UVC_GET_DEF:
1782 		reqflags = UVC_CTRL_FLAG_GET_DEF;
1783 		break;
1784 	case UVC_GET_RES:
1785 		reqflags = UVC_CTRL_FLAG_GET_RES;
1786 		break;
1787 	case UVC_SET_CUR:
1788 		reqflags = UVC_CTRL_FLAG_SET_CUR;
1789 		break;
1790 	case UVC_GET_LEN:
1791 		size = 2;
1792 		break;
1793 	case UVC_GET_INFO:
1794 		size = 1;
1795 		break;
1796 	default:
1797 		ret = -EINVAL;
1798 		goto done;
1799 	}
1800 
1801 	if (size != xqry->size) {
1802 		ret = -ENOBUFS;
1803 		goto done;
1804 	}
1805 
1806 	if (reqflags && !(ctrl->info.flags & reqflags)) {
1807 		ret = -EBADRQC;
1808 		goto done;
1809 	}
1810 
1811 	data = kmalloc(size, GFP_KERNEL);
1812 	if (data == NULL) {
1813 		ret = -ENOMEM;
1814 		goto done;
1815 	}
1816 
1817 	if (xqry->query == UVC_SET_CUR &&
1818 	    copy_from_user(data, xqry->data, size)) {
1819 		ret = -EFAULT;
1820 		goto done;
1821 	}
1822 
1823 	ret = uvc_query_ctrl(chain->dev, xqry->query, xqry->unit,
1824 			     chain->dev->intfnum, xqry->selector, data, size);
1825 	if (ret < 0)
1826 		goto done;
1827 
1828 	if (xqry->query != UVC_SET_CUR &&
1829 	    copy_to_user(xqry->data, data, size))
1830 		ret = -EFAULT;
1831 done:
1832 	kfree(data);
1833 	mutex_unlock(&chain->ctrl_mutex);
1834 	return ret;
1835 }
1836 
1837 /* --------------------------------------------------------------------------
1838  * Suspend/resume
1839  */
1840 
1841 /*
1842  * Restore control values after resume, skipping controls that haven't been
1843  * changed.
1844  *
1845  * TODO
1846  * - Don't restore modified controls that are back to their default value.
1847  * - Handle restore order (Auto-Exposure Mode should be restored before
1848  *   Exposure Time).
1849  */
1850 int uvc_ctrl_restore_values(struct uvc_device *dev)
1851 {
1852 	struct uvc_control *ctrl;
1853 	struct uvc_entity *entity;
1854 	unsigned int i;
1855 	int ret;
1856 
1857 	/* Walk the entities list and restore controls when possible. */
1858 	list_for_each_entry(entity, &dev->entities, list) {
1859 
1860 		for (i = 0; i < entity->ncontrols; ++i) {
1861 			ctrl = &entity->controls[i];
1862 
1863 			if (!ctrl->initialized || !ctrl->modified ||
1864 			    (ctrl->info.flags & UVC_CTRL_FLAG_RESTORE) == 0)
1865 				continue;
1866 
1867 			printk(KERN_INFO "restoring control %pUl/%u/%u\n",
1868 				ctrl->info.entity, ctrl->info.index,
1869 				ctrl->info.selector);
1870 			ctrl->dirty = 1;
1871 		}
1872 
1873 		ret = uvc_ctrl_commit_entity(dev, entity, 0);
1874 		if (ret < 0)
1875 			return ret;
1876 	}
1877 
1878 	return 0;
1879 }
1880 
1881 /* --------------------------------------------------------------------------
1882  * Control and mapping handling
1883  */
1884 
1885 /*
1886  * Add control information to a given control.
1887  */
1888 static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
1889 	const struct uvc_control_info *info)
1890 {
1891 	int ret = 0;
1892 
1893 	ctrl->info = *info;
1894 	INIT_LIST_HEAD(&ctrl->info.mappings);
1895 
1896 	/* Allocate an array to save control values (cur, def, max, etc.) */
1897 	ctrl->uvc_data = kzalloc(ctrl->info.size * UVC_CTRL_DATA_LAST + 1,
1898 				 GFP_KERNEL);
1899 	if (ctrl->uvc_data == NULL) {
1900 		ret = -ENOMEM;
1901 		goto done;
1902 	}
1903 
1904 	ctrl->initialized = 1;
1905 
1906 	uvc_trace(UVC_TRACE_CONTROL, "Added control %pUl/%u to device %s "
1907 		"entity %u\n", ctrl->info.entity, ctrl->info.selector,
1908 		dev->udev->devpath, ctrl->entity->id);
1909 
1910 done:
1911 	if (ret < 0)
1912 		kfree(ctrl->uvc_data);
1913 	return ret;
1914 }
1915 
1916 /*
1917  * Add a control mapping to a given control.
1918  */
1919 static int __uvc_ctrl_add_mapping(struct uvc_device *dev,
1920 	struct uvc_control *ctrl, const struct uvc_control_mapping *mapping)
1921 {
1922 	struct uvc_control_mapping *map;
1923 	unsigned int size;
1924 
1925 	/* Most mappings come from static kernel data and need to be duplicated.
1926 	 * Mappings that come from userspace will be unnecessarily duplicated,
1927 	 * this could be optimized.
1928 	 */
1929 	map = kmemdup(mapping, sizeof(*mapping), GFP_KERNEL);
1930 	if (map == NULL)
1931 		return -ENOMEM;
1932 
1933 	INIT_LIST_HEAD(&map->ev_subs);
1934 
1935 	size = sizeof(*mapping->menu_info) * mapping->menu_count;
1936 	map->menu_info = kmemdup(mapping->menu_info, size, GFP_KERNEL);
1937 	if (map->menu_info == NULL) {
1938 		kfree(map);
1939 		return -ENOMEM;
1940 	}
1941 
1942 	if (map->get == NULL)
1943 		map->get = uvc_get_le_value;
1944 	if (map->set == NULL)
1945 		map->set = uvc_set_le_value;
1946 
1947 	list_add_tail(&map->list, &ctrl->info.mappings);
1948 	uvc_trace(UVC_TRACE_CONTROL,
1949 		"Adding mapping '%s' to control %pUl/%u.\n",
1950 		map->name, ctrl->info.entity, ctrl->info.selector);
1951 
1952 	return 0;
1953 }
1954 
1955 int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
1956 	const struct uvc_control_mapping *mapping)
1957 {
1958 	struct uvc_device *dev = chain->dev;
1959 	struct uvc_control_mapping *map;
1960 	struct uvc_entity *entity;
1961 	struct uvc_control *ctrl;
1962 	int found = 0;
1963 	int ret;
1964 
1965 	if (mapping->id & ~V4L2_CTRL_ID_MASK) {
1966 		uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', control "
1967 			"id 0x%08x is invalid.\n", mapping->name,
1968 			mapping->id);
1969 		return -EINVAL;
1970 	}
1971 
1972 	/* Search for the matching (GUID/CS) control on the current chain */
1973 	list_for_each_entry(entity, &chain->entities, chain) {
1974 		unsigned int i;
1975 
1976 		if (UVC_ENTITY_TYPE(entity) != UVC_VC_EXTENSION_UNIT ||
1977 		    !uvc_entity_match_guid(entity, mapping->entity))
1978 			continue;
1979 
1980 		for (i = 0; i < entity->ncontrols; ++i) {
1981 			ctrl = &entity->controls[i];
1982 			if (ctrl->index == mapping->selector - 1) {
1983 				found = 1;
1984 				break;
1985 			}
1986 		}
1987 
1988 		if (found)
1989 			break;
1990 	}
1991 	if (!found)
1992 		return -ENOENT;
1993 
1994 	if (mutex_lock_interruptible(&chain->ctrl_mutex))
1995 		return -ERESTARTSYS;
1996 
1997 	/* Perform delayed initialization of XU controls */
1998 	ret = uvc_ctrl_init_xu_ctrl(dev, ctrl);
1999 	if (ret < 0) {
2000 		ret = -ENOENT;
2001 		goto done;
2002 	}
2003 
2004 	list_for_each_entry(map, &ctrl->info.mappings, list) {
2005 		if (mapping->id == map->id) {
2006 			uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', "
2007 				"control id 0x%08x already exists.\n",
2008 				mapping->name, mapping->id);
2009 			ret = -EEXIST;
2010 			goto done;
2011 		}
2012 	}
2013 
2014 	/* Prevent excess memory consumption */
2015 	if (atomic_inc_return(&dev->nmappings) > UVC_MAX_CONTROL_MAPPINGS) {
2016 		atomic_dec(&dev->nmappings);
2017 		uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', maximum "
2018 			"mappings count (%u) exceeded.\n", mapping->name,
2019 			UVC_MAX_CONTROL_MAPPINGS);
2020 		ret = -ENOMEM;
2021 		goto done;
2022 	}
2023 
2024 	ret = __uvc_ctrl_add_mapping(dev, ctrl, mapping);
2025 	if (ret < 0)
2026 		atomic_dec(&dev->nmappings);
2027 
2028 done:
2029 	mutex_unlock(&chain->ctrl_mutex);
2030 	return ret;
2031 }
2032 
2033 /*
2034  * Prune an entity of its bogus controls using a blacklist. Bogus controls
2035  * are currently the ones that crash the camera or unconditionally return an
2036  * error when queried.
2037  */
2038 static void uvc_ctrl_prune_entity(struct uvc_device *dev,
2039 	struct uvc_entity *entity)
2040 {
2041 	struct uvc_ctrl_blacklist {
2042 		struct usb_device_id id;
2043 		u8 index;
2044 	};
2045 
2046 	static const struct uvc_ctrl_blacklist processing_blacklist[] = {
2047 		{ { USB_DEVICE(0x13d3, 0x509b) }, 9 }, /* Gain */
2048 		{ { USB_DEVICE(0x1c4f, 0x3000) }, 6 }, /* WB Temperature */
2049 		{ { USB_DEVICE(0x5986, 0x0241) }, 2 }, /* Hue */
2050 	};
2051 	static const struct uvc_ctrl_blacklist camera_blacklist[] = {
2052 		{ { USB_DEVICE(0x06f8, 0x3005) }, 9 }, /* Zoom, Absolute */
2053 	};
2054 
2055 	const struct uvc_ctrl_blacklist *blacklist;
2056 	unsigned int size;
2057 	unsigned int count;
2058 	unsigned int i;
2059 	u8 *controls;
2060 
2061 	switch (UVC_ENTITY_TYPE(entity)) {
2062 	case UVC_VC_PROCESSING_UNIT:
2063 		blacklist = processing_blacklist;
2064 		count = ARRAY_SIZE(processing_blacklist);
2065 		controls = entity->processing.bmControls;
2066 		size = entity->processing.bControlSize;
2067 		break;
2068 
2069 	case UVC_ITT_CAMERA:
2070 		blacklist = camera_blacklist;
2071 		count = ARRAY_SIZE(camera_blacklist);
2072 		controls = entity->camera.bmControls;
2073 		size = entity->camera.bControlSize;
2074 		break;
2075 
2076 	default:
2077 		return;
2078 	}
2079 
2080 	for (i = 0; i < count; ++i) {
2081 		if (!usb_match_one_id(dev->intf, &blacklist[i].id))
2082 			continue;
2083 
2084 		if (blacklist[i].index >= 8 * size ||
2085 		    !uvc_test_bit(controls, blacklist[i].index))
2086 			continue;
2087 
2088 		uvc_trace(UVC_TRACE_CONTROL, "%u/%u control is black listed, "
2089 			"removing it.\n", entity->id, blacklist[i].index);
2090 
2091 		uvc_clear_bit(controls, blacklist[i].index);
2092 	}
2093 }
2094 
2095 /*
2096  * Add control information and hardcoded stock control mappings to the given
2097  * device.
2098  */
2099 static void uvc_ctrl_init_ctrl(struct uvc_device *dev, struct uvc_control *ctrl)
2100 {
2101 	const struct uvc_control_info *info = uvc_ctrls;
2102 	const struct uvc_control_info *iend = info + ARRAY_SIZE(uvc_ctrls);
2103 	const struct uvc_control_mapping *mapping = uvc_ctrl_mappings;
2104 	const struct uvc_control_mapping *mend =
2105 		mapping + ARRAY_SIZE(uvc_ctrl_mappings);
2106 
2107 	/* XU controls initialization requires querying the device for control
2108 	 * information. As some buggy UVC devices will crash when queried
2109 	 * repeatedly in a tight loop, delay XU controls initialization until
2110 	 * first use.
2111 	 */
2112 	if (UVC_ENTITY_TYPE(ctrl->entity) == UVC_VC_EXTENSION_UNIT)
2113 		return;
2114 
2115 	for (; info < iend; ++info) {
2116 		if (uvc_entity_match_guid(ctrl->entity, info->entity) &&
2117 		    ctrl->index == info->index) {
2118 			uvc_ctrl_add_info(dev, ctrl, info);
2119 			break;
2120 		 }
2121 	}
2122 
2123 	if (!ctrl->initialized)
2124 		return;
2125 
2126 	for (; mapping < mend; ++mapping) {
2127 		if (uvc_entity_match_guid(ctrl->entity, mapping->entity) &&
2128 		    ctrl->info.selector == mapping->selector)
2129 			__uvc_ctrl_add_mapping(dev, ctrl, mapping);
2130 	}
2131 }
2132 
2133 /*
2134  * Initialize device controls.
2135  */
2136 int uvc_ctrl_init_device(struct uvc_device *dev)
2137 {
2138 	struct uvc_entity *entity;
2139 	unsigned int i;
2140 
2141 	/* Walk the entities list and instantiate controls */
2142 	list_for_each_entry(entity, &dev->entities, list) {
2143 		struct uvc_control *ctrl;
2144 		unsigned int bControlSize = 0, ncontrols;
2145 		__u8 *bmControls = NULL;
2146 
2147 		if (UVC_ENTITY_TYPE(entity) == UVC_VC_EXTENSION_UNIT) {
2148 			bmControls = entity->extension.bmControls;
2149 			bControlSize = entity->extension.bControlSize;
2150 		} else if (UVC_ENTITY_TYPE(entity) == UVC_VC_PROCESSING_UNIT) {
2151 			bmControls = entity->processing.bmControls;
2152 			bControlSize = entity->processing.bControlSize;
2153 		} else if (UVC_ENTITY_TYPE(entity) == UVC_ITT_CAMERA) {
2154 			bmControls = entity->camera.bmControls;
2155 			bControlSize = entity->camera.bControlSize;
2156 		}
2157 
2158 		/* Remove bogus/blacklisted controls */
2159 		uvc_ctrl_prune_entity(dev, entity);
2160 
2161 		/* Count supported controls and allocate the controls array */
2162 		ncontrols = memweight(bmControls, bControlSize);
2163 		if (ncontrols == 0)
2164 			continue;
2165 
2166 		entity->controls = kcalloc(ncontrols, sizeof(*ctrl),
2167 					   GFP_KERNEL);
2168 		if (entity->controls == NULL)
2169 			return -ENOMEM;
2170 		entity->ncontrols = ncontrols;
2171 
2172 		/* Initialize all supported controls */
2173 		ctrl = entity->controls;
2174 		for (i = 0; i < bControlSize * 8; ++i) {
2175 			if (uvc_test_bit(bmControls, i) == 0)
2176 				continue;
2177 
2178 			ctrl->entity = entity;
2179 			ctrl->index = i;
2180 
2181 			uvc_ctrl_init_ctrl(dev, ctrl);
2182 			ctrl++;
2183 		}
2184 	}
2185 
2186 	return 0;
2187 }
2188 
2189 /*
2190  * Cleanup device controls.
2191  */
2192 static void uvc_ctrl_cleanup_mappings(struct uvc_device *dev,
2193 	struct uvc_control *ctrl)
2194 {
2195 	struct uvc_control_mapping *mapping, *nm;
2196 
2197 	list_for_each_entry_safe(mapping, nm, &ctrl->info.mappings, list) {
2198 		list_del(&mapping->list);
2199 		kfree(mapping->menu_info);
2200 		kfree(mapping);
2201 	}
2202 }
2203 
2204 void uvc_ctrl_cleanup_device(struct uvc_device *dev)
2205 {
2206 	struct uvc_entity *entity;
2207 	unsigned int i;
2208 
2209 	/* Free controls and control mappings for all entities. */
2210 	list_for_each_entry(entity, &dev->entities, list) {
2211 		for (i = 0; i < entity->ncontrols; ++i) {
2212 			struct uvc_control *ctrl = &entity->controls[i];
2213 
2214 			if (!ctrl->initialized)
2215 				continue;
2216 
2217 			uvc_ctrl_cleanup_mappings(dev, ctrl);
2218 			kfree(ctrl->uvc_data);
2219 		}
2220 
2221 		kfree(entity->controls);
2222 	}
2223 }
2224