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1 /*
2  *	Video for Linux Two
3  *
4  *	A generic video device interface for the LINUX operating system
5  *	using a set of device structures/vectors for low level operations.
6  *
7  *	This file replaces the videodev.c file that comes with the
8  *	regular kernel distribution.
9  *
10  *	This program is free software; you can redistribute it and/or
11  *	modify it under the terms of the GNU General Public License
12  *	as published by the Free Software Foundation; either version
13  *	2 of the License, or (at your option) any later version.
14  *
15  * Author:	Bill Dirks <bill@thedirks.org>
16  *		based on code by Alan Cox, <alan@cymru.net>
17  *
18  */
19 
20 /*
21  * Video capture interface for Linux
22  *
23  *	A generic video device interface for the LINUX operating system
24  *	using a set of device structures/vectors for low level operations.
25  *
26  *		This program is free software; you can redistribute it and/or
27  *		modify it under the terms of the GNU General Public License
28  *		as published by the Free Software Foundation; either version
29  *		2 of the License, or (at your option) any later version.
30  *
31  * Author:	Alan Cox, <alan@lxorguk.ukuu.org.uk>
32  *
33  * Fixes:
34  */
35 
36 /*
37  * Video4linux 1/2 integration by Justin Schoeman
38  * <justin@suntiger.ee.up.ac.za>
39  * 2.4 PROCFS support ported from 2.4 kernels by
40  *  Iñaki García Etxebarria <garetxe@euskalnet.net>
41  * Makefile fix by "W. Michael Petullo" <mike@flyn.org>
42  * 2.4 devfs support ported from 2.4 kernels by
43  *  Dan Merillat <dan@merillat.org>
44  * Added Gerd Knorrs v4l1 enhancements (Justin Schoeman)
45  */
46 
47 #include <linux/module.h>
48 #include <linux/types.h>
49 #include <linux/kernel.h>
50 #include <linux/mm.h>
51 #include <linux/string.h>
52 #include <linux/errno.h>
53 #include <linux/i2c.h>
54 #include <asm/uaccess.h>
55 #include <asm/system.h>
56 #include <asm/pgtable.h>
57 #include <asm/io.h>
58 #include <asm/div64.h>
59 #define __OLD_VIDIOC_ /* To allow fixing old calls*/
60 #include <media/v4l2-common.h>
61 #include <media/v4l2-device.h>
62 #include <media/v4l2-chip-ident.h>
63 
64 #include <linux/videodev2.h>
65 
66 MODULE_AUTHOR("Bill Dirks, Justin Schoeman, Gerd Knorr");
67 MODULE_DESCRIPTION("misc helper functions for v4l2 device drivers");
68 MODULE_LICENSE("GPL");
69 
70 /*
71  *
72  *	V 4 L 2   D R I V E R   H E L P E R   A P I
73  *
74  */
75 
76 /*
77  *  Video Standard Operations (contributed by Michael Schimek)
78  */
79 
80 
81 /* ----------------------------------------------------------------- */
82 /* priority handling                                                 */
83 
84 #define V4L2_PRIO_VALID(val) (val == V4L2_PRIORITY_BACKGROUND   || \
85 			      val == V4L2_PRIORITY_INTERACTIVE  || \
86 			      val == V4L2_PRIORITY_RECORD)
87 
v4l2_prio_init(struct v4l2_prio_state * global)88 int v4l2_prio_init(struct v4l2_prio_state *global)
89 {
90 	memset(global,0,sizeof(*global));
91 	return 0;
92 }
93 EXPORT_SYMBOL(v4l2_prio_init);
94 
v4l2_prio_change(struct v4l2_prio_state * global,enum v4l2_priority * local,enum v4l2_priority new)95 int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
96 		     enum v4l2_priority new)
97 {
98 	if (!V4L2_PRIO_VALID(new))
99 		return -EINVAL;
100 	if (*local == new)
101 		return 0;
102 
103 	atomic_inc(&global->prios[new]);
104 	if (V4L2_PRIO_VALID(*local))
105 		atomic_dec(&global->prios[*local]);
106 	*local = new;
107 	return 0;
108 }
109 EXPORT_SYMBOL(v4l2_prio_change);
110 
v4l2_prio_open(struct v4l2_prio_state * global,enum v4l2_priority * local)111 int v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local)
112 {
113 	return v4l2_prio_change(global,local,V4L2_PRIORITY_DEFAULT);
114 }
115 EXPORT_SYMBOL(v4l2_prio_open);
116 
v4l2_prio_close(struct v4l2_prio_state * global,enum v4l2_priority * local)117 int v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority *local)
118 {
119 	if (V4L2_PRIO_VALID(*local))
120 		atomic_dec(&global->prios[*local]);
121 	return 0;
122 }
123 EXPORT_SYMBOL(v4l2_prio_close);
124 
v4l2_prio_max(struct v4l2_prio_state * global)125 enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global)
126 {
127 	if (atomic_read(&global->prios[V4L2_PRIORITY_RECORD]) > 0)
128 		return V4L2_PRIORITY_RECORD;
129 	if (atomic_read(&global->prios[V4L2_PRIORITY_INTERACTIVE]) > 0)
130 		return V4L2_PRIORITY_INTERACTIVE;
131 	if (atomic_read(&global->prios[V4L2_PRIORITY_BACKGROUND]) > 0)
132 		return V4L2_PRIORITY_BACKGROUND;
133 	return V4L2_PRIORITY_UNSET;
134 }
135 EXPORT_SYMBOL(v4l2_prio_max);
136 
v4l2_prio_check(struct v4l2_prio_state * global,enum v4l2_priority * local)137 int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority *local)
138 {
139 	if (*local < v4l2_prio_max(global))
140 		return -EBUSY;
141 	return 0;
142 }
143 EXPORT_SYMBOL(v4l2_prio_check);
144 
145 /* ----------------------------------------------------------------- */
146 
147 /* Helper functions for control handling			     */
148 
149 /* Check for correctness of the ctrl's value based on the data from
150    struct v4l2_queryctrl and the available menu items. Note that
151    menu_items may be NULL, in that case it is ignored. */
v4l2_ctrl_check(struct v4l2_ext_control * ctrl,struct v4l2_queryctrl * qctrl,const char ** menu_items)152 int v4l2_ctrl_check(struct v4l2_ext_control *ctrl, struct v4l2_queryctrl *qctrl,
153 		const char **menu_items)
154 {
155 	if (qctrl->flags & V4L2_CTRL_FLAG_DISABLED)
156 		return -EINVAL;
157 	if (qctrl->flags & V4L2_CTRL_FLAG_GRABBED)
158 		return -EBUSY;
159 	if (qctrl->type == V4L2_CTRL_TYPE_BUTTON ||
160 	    qctrl->type == V4L2_CTRL_TYPE_INTEGER64 ||
161 	    qctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
162 		return 0;
163 	if (ctrl->value < qctrl->minimum || ctrl->value > qctrl->maximum)
164 		return -ERANGE;
165 	if (qctrl->type == V4L2_CTRL_TYPE_MENU && menu_items != NULL) {
166 		if (menu_items[ctrl->value] == NULL ||
167 		    menu_items[ctrl->value][0] == '\0')
168 			return -EINVAL;
169 	}
170 	return 0;
171 }
172 EXPORT_SYMBOL(v4l2_ctrl_check);
173 
174 /* Returns NULL or a character pointer array containing the menu for
175    the given control ID. The pointer array ends with a NULL pointer.
176    An empty string signifies a menu entry that is invalid. This allows
177    drivers to disable certain options if it is not supported. */
v4l2_ctrl_get_menu(u32 id)178 const char **v4l2_ctrl_get_menu(u32 id)
179 {
180 	static const char *mpeg_audio_sampling_freq[] = {
181 		"44.1 kHz",
182 		"48 kHz",
183 		"32 kHz",
184 		NULL
185 	};
186 	static const char *mpeg_audio_encoding[] = {
187 		"MPEG-1/2 Layer I",
188 		"MPEG-1/2 Layer II",
189 		"MPEG-1/2 Layer III",
190 		"MPEG-2/4 AAC",
191 		"AC-3",
192 		NULL
193 	};
194 	static const char *mpeg_audio_l1_bitrate[] = {
195 		"32 kbps",
196 		"64 kbps",
197 		"96 kbps",
198 		"128 kbps",
199 		"160 kbps",
200 		"192 kbps",
201 		"224 kbps",
202 		"256 kbps",
203 		"288 kbps",
204 		"320 kbps",
205 		"352 kbps",
206 		"384 kbps",
207 		"416 kbps",
208 		"448 kbps",
209 		NULL
210 	};
211 	static const char *mpeg_audio_l2_bitrate[] = {
212 		"32 kbps",
213 		"48 kbps",
214 		"56 kbps",
215 		"64 kbps",
216 		"80 kbps",
217 		"96 kbps",
218 		"112 kbps",
219 		"128 kbps",
220 		"160 kbps",
221 		"192 kbps",
222 		"224 kbps",
223 		"256 kbps",
224 		"320 kbps",
225 		"384 kbps",
226 		NULL
227 	};
228 	static const char *mpeg_audio_l3_bitrate[] = {
229 		"32 kbps",
230 		"40 kbps",
231 		"48 kbps",
232 		"56 kbps",
233 		"64 kbps",
234 		"80 kbps",
235 		"96 kbps",
236 		"112 kbps",
237 		"128 kbps",
238 		"160 kbps",
239 		"192 kbps",
240 		"224 kbps",
241 		"256 kbps",
242 		"320 kbps",
243 		NULL
244 	};
245 	static const char *mpeg_audio_ac3_bitrate[] = {
246 		"32 kbps",
247 		"40 kbps",
248 		"48 kbps",
249 		"56 kbps",
250 		"64 kbps",
251 		"80 kbps",
252 		"96 kbps",
253 		"112 kbps",
254 		"128 kbps",
255 		"160 kbps",
256 		"192 kbps",
257 		"224 kbps",
258 		"256 kbps",
259 		"320 kbps",
260 		"384 kbps",
261 		"448 kbps",
262 		"512 kbps",
263 		"576 kbps",
264 		"640 kbps",
265 		NULL
266 	};
267 	static const char *mpeg_audio_mode[] = {
268 		"Stereo",
269 		"Joint Stereo",
270 		"Dual",
271 		"Mono",
272 		NULL
273 	};
274 	static const char *mpeg_audio_mode_extension[] = {
275 		"Bound 4",
276 		"Bound 8",
277 		"Bound 12",
278 		"Bound 16",
279 		NULL
280 	};
281 	static const char *mpeg_audio_emphasis[] = {
282 		"No Emphasis",
283 		"50/15 us",
284 		"CCITT J17",
285 		NULL
286 	};
287 	static const char *mpeg_audio_crc[] = {
288 		"No CRC",
289 		"16-bit CRC",
290 		NULL
291 	};
292 	static const char *mpeg_video_encoding[] = {
293 		"MPEG-1",
294 		"MPEG-2",
295 		"MPEG-4 AVC",
296 		NULL
297 	};
298 	static const char *mpeg_video_aspect[] = {
299 		"1x1",
300 		"4x3",
301 		"16x9",
302 		"2.21x1",
303 		NULL
304 	};
305 	static const char *mpeg_video_bitrate_mode[] = {
306 		"Variable Bitrate",
307 		"Constant Bitrate",
308 		NULL
309 	};
310 	static const char *mpeg_stream_type[] = {
311 		"MPEG-2 Program Stream",
312 		"MPEG-2 Transport Stream",
313 		"MPEG-1 System Stream",
314 		"MPEG-2 DVD-compatible Stream",
315 		"MPEG-1 VCD-compatible Stream",
316 		"MPEG-2 SVCD-compatible Stream",
317 		NULL
318 	};
319 	static const char *mpeg_stream_vbi_fmt[] = {
320 		"No VBI",
321 		"Private packet, IVTV format",
322 		NULL
323 	};
324 	static const char *camera_power_line_frequency[] = {
325 		"Disabled",
326 		"50 Hz",
327 		"60 Hz",
328 		NULL
329 	};
330 	static const char *camera_exposure_auto[] = {
331 		"Auto Mode",
332 		"Manual Mode",
333 		"Shutter Priority Mode",
334 		"Aperture Priority Mode",
335 		NULL
336 	};
337 
338 	switch (id) {
339 		case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
340 			return mpeg_audio_sampling_freq;
341 		case V4L2_CID_MPEG_AUDIO_ENCODING:
342 			return mpeg_audio_encoding;
343 		case V4L2_CID_MPEG_AUDIO_L1_BITRATE:
344 			return mpeg_audio_l1_bitrate;
345 		case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
346 			return mpeg_audio_l2_bitrate;
347 		case V4L2_CID_MPEG_AUDIO_L3_BITRATE:
348 			return mpeg_audio_l3_bitrate;
349 		case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
350 			return mpeg_audio_ac3_bitrate;
351 		case V4L2_CID_MPEG_AUDIO_MODE:
352 			return mpeg_audio_mode;
353 		case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
354 			return mpeg_audio_mode_extension;
355 		case V4L2_CID_MPEG_AUDIO_EMPHASIS:
356 			return mpeg_audio_emphasis;
357 		case V4L2_CID_MPEG_AUDIO_CRC:
358 			return mpeg_audio_crc;
359 		case V4L2_CID_MPEG_VIDEO_ENCODING:
360 			return mpeg_video_encoding;
361 		case V4L2_CID_MPEG_VIDEO_ASPECT:
362 			return mpeg_video_aspect;
363 		case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
364 			return mpeg_video_bitrate_mode;
365 		case V4L2_CID_MPEG_STREAM_TYPE:
366 			return mpeg_stream_type;
367 		case V4L2_CID_MPEG_STREAM_VBI_FMT:
368 			return mpeg_stream_vbi_fmt;
369 		case V4L2_CID_POWER_LINE_FREQUENCY:
370 			return camera_power_line_frequency;
371 		case V4L2_CID_EXPOSURE_AUTO:
372 			return camera_exposure_auto;
373 		default:
374 			return NULL;
375 	}
376 }
377 EXPORT_SYMBOL(v4l2_ctrl_get_menu);
378 
379 /* Return the control name. */
v4l2_ctrl_get_name(u32 id)380 const char *v4l2_ctrl_get_name(u32 id)
381 {
382 	switch (id) {
383 	/* USER controls */
384 	case V4L2_CID_USER_CLASS: 		return "User Controls";
385 	case V4L2_CID_AUDIO_VOLUME: 		return "Volume";
386 	case V4L2_CID_AUDIO_MUTE: 		return "Mute";
387 	case V4L2_CID_AUDIO_BALANCE: 		return "Balance";
388 	case V4L2_CID_AUDIO_BASS: 		return "Bass";
389 	case V4L2_CID_AUDIO_TREBLE: 		return "Treble";
390 	case V4L2_CID_AUDIO_LOUDNESS: 		return "Loudness";
391 	case V4L2_CID_BRIGHTNESS: 		return "Brightness";
392 	case V4L2_CID_CONTRAST: 		return "Contrast";
393 	case V4L2_CID_SATURATION: 		return "Saturation";
394 	case V4L2_CID_HUE: 			return "Hue";
395 	case V4L2_CID_BLACK_LEVEL:		return "Black Level";
396 	case V4L2_CID_AUTO_WHITE_BALANCE:	return "White Balance, Automatic";
397 	case V4L2_CID_DO_WHITE_BALANCE:		return "Do White Balance";
398 	case V4L2_CID_RED_BALANCE:		return "Red Balance";
399 	case V4L2_CID_BLUE_BALANCE:		return "Blue Balance";
400 	case V4L2_CID_GAMMA:			return "Gamma";
401 	case V4L2_CID_EXPOSURE:			return "Exposure";
402 	case V4L2_CID_AUTOGAIN:			return "Gain, Automatic";
403 	case V4L2_CID_GAIN:			return "Gain";
404 	case V4L2_CID_HFLIP:			return "Horizontal Flip";
405 	case V4L2_CID_VFLIP:			return "Vertical Flip";
406 	case V4L2_CID_HCENTER:			return "Horizontal Center";
407 	case V4L2_CID_VCENTER:			return "Vertical Center";
408 	case V4L2_CID_POWER_LINE_FREQUENCY:	return "Power Line Frequency";
409 	case V4L2_CID_HUE_AUTO:			return "Hue, Automatic";
410 	case V4L2_CID_WHITE_BALANCE_TEMPERATURE: return "White Balance Temperature";
411 	case V4L2_CID_SHARPNESS:		return "Sharpness";
412 	case V4L2_CID_BACKLIGHT_COMPENSATION:	return "Backlight Compensation";
413 	case V4L2_CID_CHROMA_AGC:		return "Chroma AGC";
414 	case V4L2_CID_COLOR_KILLER:		return "Color Killer";
415 
416 	/* MPEG controls */
417 	case V4L2_CID_MPEG_CLASS: 		return "MPEG Encoder Controls";
418 	case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ: return "Audio Sampling Frequency";
419 	case V4L2_CID_MPEG_AUDIO_ENCODING: 	return "Audio Encoding";
420 	case V4L2_CID_MPEG_AUDIO_L1_BITRATE: 	return "Audio Layer I Bitrate";
421 	case V4L2_CID_MPEG_AUDIO_L2_BITRATE: 	return "Audio Layer II Bitrate";
422 	case V4L2_CID_MPEG_AUDIO_L3_BITRATE: 	return "Audio Layer III Bitrate";
423 	case V4L2_CID_MPEG_AUDIO_AAC_BITRATE: 	return "Audio AAC Bitrate";
424 	case V4L2_CID_MPEG_AUDIO_AC3_BITRATE: 	return "Audio AC-3 Bitrate";
425 	case V4L2_CID_MPEG_AUDIO_MODE: 		return "Audio Stereo Mode";
426 	case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION: return "Audio Stereo Mode Extension";
427 	case V4L2_CID_MPEG_AUDIO_EMPHASIS: 	return "Audio Emphasis";
428 	case V4L2_CID_MPEG_AUDIO_CRC: 		return "Audio CRC";
429 	case V4L2_CID_MPEG_AUDIO_MUTE: 		return "Audio Mute";
430 	case V4L2_CID_MPEG_VIDEO_ENCODING: 	return "Video Encoding";
431 	case V4L2_CID_MPEG_VIDEO_ASPECT: 	return "Video Aspect";
432 	case V4L2_CID_MPEG_VIDEO_B_FRAMES: 	return "Video B Frames";
433 	case V4L2_CID_MPEG_VIDEO_GOP_SIZE: 	return "Video GOP Size";
434 	case V4L2_CID_MPEG_VIDEO_GOP_CLOSURE: 	return "Video GOP Closure";
435 	case V4L2_CID_MPEG_VIDEO_PULLDOWN: 	return "Video Pulldown";
436 	case V4L2_CID_MPEG_VIDEO_BITRATE_MODE: 	return "Video Bitrate Mode";
437 	case V4L2_CID_MPEG_VIDEO_BITRATE: 	return "Video Bitrate";
438 	case V4L2_CID_MPEG_VIDEO_BITRATE_PEAK: 	return "Video Peak Bitrate";
439 	case V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION: return "Video Temporal Decimation";
440 	case V4L2_CID_MPEG_VIDEO_MUTE: 		return "Video Mute";
441 	case V4L2_CID_MPEG_VIDEO_MUTE_YUV:	return "Video Mute YUV";
442 	case V4L2_CID_MPEG_STREAM_TYPE: 	return "Stream Type";
443 	case V4L2_CID_MPEG_STREAM_PID_PMT: 	return "Stream PMT Program ID";
444 	case V4L2_CID_MPEG_STREAM_PID_AUDIO: 	return "Stream Audio Program ID";
445 	case V4L2_CID_MPEG_STREAM_PID_VIDEO: 	return "Stream Video Program ID";
446 	case V4L2_CID_MPEG_STREAM_PID_PCR: 	return "Stream PCR Program ID";
447 	case V4L2_CID_MPEG_STREAM_PES_ID_AUDIO: return "Stream PES Audio ID";
448 	case V4L2_CID_MPEG_STREAM_PES_ID_VIDEO: return "Stream PES Video ID";
449 	case V4L2_CID_MPEG_STREAM_VBI_FMT:	return "Stream VBI Format";
450 
451 	/* CAMERA controls */
452 	case V4L2_CID_CAMERA_CLASS:		return "Camera Controls";
453 	case V4L2_CID_EXPOSURE_AUTO:		return "Auto Exposure";
454 	case V4L2_CID_EXPOSURE_ABSOLUTE:	return "Exposure Time, Absolute";
455 	case V4L2_CID_EXPOSURE_AUTO_PRIORITY:	return "Exposure, Dynamic Framerate";
456 	case V4L2_CID_PAN_RELATIVE:		return "Pan, Relative";
457 	case V4L2_CID_TILT_RELATIVE:		return "Tilt, Relative";
458 	case V4L2_CID_PAN_RESET:		return "Pan, Reset";
459 	case V4L2_CID_TILT_RESET:		return "Tilt, Reset";
460 	case V4L2_CID_PAN_ABSOLUTE:		return "Pan, Absolute";
461 	case V4L2_CID_TILT_ABSOLUTE:		return "Tilt, Absolute";
462 	case V4L2_CID_FOCUS_ABSOLUTE:		return "Focus, Absolute";
463 	case V4L2_CID_FOCUS_RELATIVE:		return "Focus, Relative";
464 	case V4L2_CID_FOCUS_AUTO:		return "Focus, Automatic";
465 	case V4L2_CID_ZOOM_ABSOLUTE:		return "Zoom, Absolute";
466 	case V4L2_CID_ZOOM_RELATIVE:		return "Zoom, Relative";
467 	case V4L2_CID_ZOOM_CONTINUOUS:		return "Zoom, Continuous";
468 	case V4L2_CID_PRIVACY:			return "Privacy";
469 
470 	default:
471 		return NULL;
472 	}
473 }
474 EXPORT_SYMBOL(v4l2_ctrl_get_name);
475 
476 /* Fill in a struct v4l2_queryctrl */
v4l2_ctrl_query_fill(struct v4l2_queryctrl * qctrl,s32 min,s32 max,s32 step,s32 def)477 int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 min, s32 max, s32 step, s32 def)
478 {
479 	const char *name = v4l2_ctrl_get_name(qctrl->id);
480 
481 	qctrl->flags = 0;
482 	if (name == NULL)
483 		return -EINVAL;
484 
485 	switch (qctrl->id) {
486 	case V4L2_CID_AUDIO_MUTE:
487 	case V4L2_CID_AUDIO_LOUDNESS:
488 	case V4L2_CID_AUTO_WHITE_BALANCE:
489 	case V4L2_CID_AUTOGAIN:
490 	case V4L2_CID_HFLIP:
491 	case V4L2_CID_VFLIP:
492 	case V4L2_CID_HUE_AUTO:
493 	case V4L2_CID_MPEG_AUDIO_MUTE:
494 	case V4L2_CID_MPEG_VIDEO_MUTE:
495 	case V4L2_CID_MPEG_VIDEO_GOP_CLOSURE:
496 	case V4L2_CID_MPEG_VIDEO_PULLDOWN:
497 	case V4L2_CID_EXPOSURE_AUTO_PRIORITY:
498 	case V4L2_CID_PRIVACY:
499 		qctrl->type = V4L2_CTRL_TYPE_BOOLEAN;
500 		min = 0;
501 		max = step = 1;
502 		break;
503 	case V4L2_CID_POWER_LINE_FREQUENCY:
504 	case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
505 	case V4L2_CID_MPEG_AUDIO_ENCODING:
506 	case V4L2_CID_MPEG_AUDIO_L1_BITRATE:
507 	case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
508 	case V4L2_CID_MPEG_AUDIO_L3_BITRATE:
509 	case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
510 	case V4L2_CID_MPEG_AUDIO_MODE:
511 	case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
512 	case V4L2_CID_MPEG_AUDIO_EMPHASIS:
513 	case V4L2_CID_MPEG_AUDIO_CRC:
514 	case V4L2_CID_MPEG_VIDEO_ENCODING:
515 	case V4L2_CID_MPEG_VIDEO_ASPECT:
516 	case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
517 	case V4L2_CID_MPEG_STREAM_TYPE:
518 	case V4L2_CID_MPEG_STREAM_VBI_FMT:
519 	case V4L2_CID_EXPOSURE_AUTO:
520 		qctrl->type = V4L2_CTRL_TYPE_MENU;
521 		step = 1;
522 		break;
523 	case V4L2_CID_USER_CLASS:
524 	case V4L2_CID_CAMERA_CLASS:
525 	case V4L2_CID_MPEG_CLASS:
526 		qctrl->type = V4L2_CTRL_TYPE_CTRL_CLASS;
527 		qctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
528 		min = max = step = def = 0;
529 		break;
530 	default:
531 		qctrl->type = V4L2_CTRL_TYPE_INTEGER;
532 		break;
533 	}
534 	switch (qctrl->id) {
535 	case V4L2_CID_MPEG_AUDIO_ENCODING:
536 	case V4L2_CID_MPEG_AUDIO_MODE:
537 	case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
538 	case V4L2_CID_MPEG_VIDEO_B_FRAMES:
539 	case V4L2_CID_MPEG_STREAM_TYPE:
540 		qctrl->flags |= V4L2_CTRL_FLAG_UPDATE;
541 		break;
542 	case V4L2_CID_AUDIO_VOLUME:
543 	case V4L2_CID_AUDIO_BALANCE:
544 	case V4L2_CID_AUDIO_BASS:
545 	case V4L2_CID_AUDIO_TREBLE:
546 	case V4L2_CID_BRIGHTNESS:
547 	case V4L2_CID_CONTRAST:
548 	case V4L2_CID_SATURATION:
549 	case V4L2_CID_HUE:
550 		qctrl->flags |= V4L2_CTRL_FLAG_SLIDER;
551 		break;
552 	}
553 	qctrl->minimum = min;
554 	qctrl->maximum = max;
555 	qctrl->step = step;
556 	qctrl->default_value = def;
557 	qctrl->reserved[0] = qctrl->reserved[1] = 0;
558 	snprintf(qctrl->name, sizeof(qctrl->name), name);
559 	return 0;
560 }
561 EXPORT_SYMBOL(v4l2_ctrl_query_fill);
562 
563 /* Fill in a struct v4l2_queryctrl with standard values based on
564    the control ID. */
v4l2_ctrl_query_fill_std(struct v4l2_queryctrl * qctrl)565 int v4l2_ctrl_query_fill_std(struct v4l2_queryctrl *qctrl)
566 {
567 	switch (qctrl->id) {
568 	/* USER controls */
569 	case V4L2_CID_USER_CLASS:
570 	case V4L2_CID_MPEG_CLASS:
571 		return v4l2_ctrl_query_fill(qctrl, 0, 0, 0, 0);
572 	case V4L2_CID_AUDIO_VOLUME:
573 		return v4l2_ctrl_query_fill(qctrl, 0, 65535, 65535 / 100, 58880);
574 	case V4L2_CID_AUDIO_MUTE:
575 	case V4L2_CID_AUDIO_LOUDNESS:
576 		return v4l2_ctrl_query_fill(qctrl, 0, 1, 1, 0);
577 	case V4L2_CID_AUDIO_BALANCE:
578 	case V4L2_CID_AUDIO_BASS:
579 	case V4L2_CID_AUDIO_TREBLE:
580 		return v4l2_ctrl_query_fill(qctrl, 0, 65535, 65535 / 100, 32768);
581 	case V4L2_CID_BRIGHTNESS:
582 		return v4l2_ctrl_query_fill(qctrl, 0, 255, 1, 128);
583 	case V4L2_CID_CONTRAST:
584 	case V4L2_CID_SATURATION:
585 		return v4l2_ctrl_query_fill(qctrl, 0, 127, 1, 64);
586 	case V4L2_CID_HUE:
587 		return v4l2_ctrl_query_fill(qctrl, -128, 127, 1, 0);
588 
589 	/* MPEG controls */
590 	case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
591 		return v4l2_ctrl_query_fill(qctrl,
592 				V4L2_MPEG_AUDIO_SAMPLING_FREQ_44100,
593 				V4L2_MPEG_AUDIO_SAMPLING_FREQ_32000, 1,
594 				V4L2_MPEG_AUDIO_SAMPLING_FREQ_48000);
595 	case V4L2_CID_MPEG_AUDIO_ENCODING:
596 		return v4l2_ctrl_query_fill(qctrl,
597 				V4L2_MPEG_AUDIO_ENCODING_LAYER_1,
598 				V4L2_MPEG_AUDIO_ENCODING_AC3, 1,
599 				V4L2_MPEG_AUDIO_ENCODING_LAYER_2);
600 	case V4L2_CID_MPEG_AUDIO_L1_BITRATE:
601 		return v4l2_ctrl_query_fill(qctrl,
602 				V4L2_MPEG_AUDIO_L1_BITRATE_32K,
603 				V4L2_MPEG_AUDIO_L1_BITRATE_448K, 1,
604 				V4L2_MPEG_AUDIO_L1_BITRATE_256K);
605 	case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
606 		return v4l2_ctrl_query_fill(qctrl,
607 				V4L2_MPEG_AUDIO_L2_BITRATE_32K,
608 				V4L2_MPEG_AUDIO_L2_BITRATE_384K, 1,
609 				V4L2_MPEG_AUDIO_L2_BITRATE_224K);
610 	case V4L2_CID_MPEG_AUDIO_L3_BITRATE:
611 		return v4l2_ctrl_query_fill(qctrl,
612 				V4L2_MPEG_AUDIO_L3_BITRATE_32K,
613 				V4L2_MPEG_AUDIO_L3_BITRATE_320K, 1,
614 				V4L2_MPEG_AUDIO_L3_BITRATE_192K);
615 	case V4L2_CID_MPEG_AUDIO_AAC_BITRATE:
616 		return v4l2_ctrl_query_fill(qctrl, 0, 6400, 1, 3200000);
617 	case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
618 		return v4l2_ctrl_query_fill(qctrl,
619 				V4L2_MPEG_AUDIO_AC3_BITRATE_32K,
620 				V4L2_MPEG_AUDIO_AC3_BITRATE_640K, 1,
621 				V4L2_MPEG_AUDIO_AC3_BITRATE_384K);
622 	case V4L2_CID_MPEG_AUDIO_MODE:
623 		return v4l2_ctrl_query_fill(qctrl,
624 				V4L2_MPEG_AUDIO_MODE_STEREO,
625 				V4L2_MPEG_AUDIO_MODE_MONO, 1,
626 				V4L2_MPEG_AUDIO_MODE_STEREO);
627 	case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
628 		return v4l2_ctrl_query_fill(qctrl,
629 				V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4,
630 				V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16, 1,
631 				V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4);
632 	case V4L2_CID_MPEG_AUDIO_EMPHASIS:
633 		return v4l2_ctrl_query_fill(qctrl,
634 				V4L2_MPEG_AUDIO_EMPHASIS_NONE,
635 				V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17, 1,
636 				V4L2_MPEG_AUDIO_EMPHASIS_NONE);
637 	case V4L2_CID_MPEG_AUDIO_CRC:
638 		return v4l2_ctrl_query_fill(qctrl,
639 				V4L2_MPEG_AUDIO_CRC_NONE,
640 				V4L2_MPEG_AUDIO_CRC_CRC16, 1,
641 				V4L2_MPEG_AUDIO_CRC_NONE);
642 	case V4L2_CID_MPEG_AUDIO_MUTE:
643 		return v4l2_ctrl_query_fill(qctrl, 0, 1, 1, 0);
644 	case V4L2_CID_MPEG_VIDEO_ENCODING:
645 		return v4l2_ctrl_query_fill(qctrl,
646 				V4L2_MPEG_VIDEO_ENCODING_MPEG_1,
647 				V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC, 1,
648 				V4L2_MPEG_VIDEO_ENCODING_MPEG_2);
649 	case V4L2_CID_MPEG_VIDEO_ASPECT:
650 		return v4l2_ctrl_query_fill(qctrl,
651 				V4L2_MPEG_VIDEO_ASPECT_1x1,
652 				V4L2_MPEG_VIDEO_ASPECT_221x100, 1,
653 				V4L2_MPEG_VIDEO_ASPECT_4x3);
654 	case V4L2_CID_MPEG_VIDEO_B_FRAMES:
655 		return v4l2_ctrl_query_fill(qctrl, 0, 33, 1, 2);
656 	case V4L2_CID_MPEG_VIDEO_GOP_SIZE:
657 		return v4l2_ctrl_query_fill(qctrl, 1, 34, 1, 12);
658 	case V4L2_CID_MPEG_VIDEO_GOP_CLOSURE:
659 		return v4l2_ctrl_query_fill(qctrl, 0, 1, 1, 1);
660 	case V4L2_CID_MPEG_VIDEO_PULLDOWN:
661 		return v4l2_ctrl_query_fill(qctrl, 0, 1, 1, 0);
662 	case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
663 		return v4l2_ctrl_query_fill(qctrl,
664 				V4L2_MPEG_VIDEO_BITRATE_MODE_VBR,
665 				V4L2_MPEG_VIDEO_BITRATE_MODE_CBR, 1,
666 				V4L2_MPEG_VIDEO_BITRATE_MODE_VBR);
667 	case V4L2_CID_MPEG_VIDEO_BITRATE:
668 		return v4l2_ctrl_query_fill(qctrl, 0, 27000000, 1, 6000000);
669 	case V4L2_CID_MPEG_VIDEO_BITRATE_PEAK:
670 		return v4l2_ctrl_query_fill(qctrl, 0, 27000000, 1, 8000000);
671 	case V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION:
672 		return v4l2_ctrl_query_fill(qctrl, 0, 255, 1, 0);
673 	case V4L2_CID_MPEG_VIDEO_MUTE:
674 		return v4l2_ctrl_query_fill(qctrl, 0, 1, 1, 0);
675 	case V4L2_CID_MPEG_VIDEO_MUTE_YUV:  /* Init YUV (really YCbCr) to black */
676 		return v4l2_ctrl_query_fill(qctrl, 0, 0xffffff, 1, 0x008080);
677 	case V4L2_CID_MPEG_STREAM_TYPE:
678 		return v4l2_ctrl_query_fill(qctrl,
679 				V4L2_MPEG_STREAM_TYPE_MPEG2_PS,
680 				V4L2_MPEG_STREAM_TYPE_MPEG2_SVCD, 1,
681 				V4L2_MPEG_STREAM_TYPE_MPEG2_PS);
682 	case V4L2_CID_MPEG_STREAM_PID_PMT:
683 		return v4l2_ctrl_query_fill(qctrl, 0, (1 << 14) - 1, 1, 16);
684 	case V4L2_CID_MPEG_STREAM_PID_AUDIO:
685 		return v4l2_ctrl_query_fill(qctrl, 0, (1 << 14) - 1, 1, 260);
686 	case V4L2_CID_MPEG_STREAM_PID_VIDEO:
687 		return v4l2_ctrl_query_fill(qctrl, 0, (1 << 14) - 1, 1, 256);
688 	case V4L2_CID_MPEG_STREAM_PID_PCR:
689 		return v4l2_ctrl_query_fill(qctrl, 0, (1 << 14) - 1, 1, 259);
690 	case V4L2_CID_MPEG_STREAM_PES_ID_AUDIO:
691 		return v4l2_ctrl_query_fill(qctrl, 0, 255, 1, 0);
692 	case V4L2_CID_MPEG_STREAM_PES_ID_VIDEO:
693 		return v4l2_ctrl_query_fill(qctrl, 0, 255, 1, 0);
694 	case V4L2_CID_MPEG_STREAM_VBI_FMT:
695 		return v4l2_ctrl_query_fill(qctrl,
696 				V4L2_MPEG_STREAM_VBI_FMT_NONE,
697 				V4L2_MPEG_STREAM_VBI_FMT_IVTV, 1,
698 				V4L2_MPEG_STREAM_VBI_FMT_NONE);
699 	default:
700 		return -EINVAL;
701 	}
702 }
703 EXPORT_SYMBOL(v4l2_ctrl_query_fill_std);
704 
705 /* Fill in a struct v4l2_querymenu based on the struct v4l2_queryctrl and
706    the menu. The qctrl pointer may be NULL, in which case it is ignored.
707    If menu_items is NULL, then the menu items are retrieved using
708    v4l2_ctrl_get_menu. */
v4l2_ctrl_query_menu(struct v4l2_querymenu * qmenu,struct v4l2_queryctrl * qctrl,const char ** menu_items)709 int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu, struct v4l2_queryctrl *qctrl,
710 	       const char **menu_items)
711 {
712 	int i;
713 
714 	qmenu->reserved = 0;
715 	if (menu_items == NULL)
716 		menu_items = v4l2_ctrl_get_menu(qmenu->id);
717 	if (menu_items == NULL ||
718 	    (qctrl && (qmenu->index < qctrl->minimum || qmenu->index > qctrl->maximum)))
719 		return -EINVAL;
720 	for (i = 0; i < qmenu->index && menu_items[i]; i++) ;
721 	if (menu_items[i] == NULL || menu_items[i][0] == '\0')
722 		return -EINVAL;
723 	snprintf(qmenu->name, sizeof(qmenu->name), menu_items[qmenu->index]);
724 	return 0;
725 }
726 EXPORT_SYMBOL(v4l2_ctrl_query_menu);
727 
728 /* Fill in a struct v4l2_querymenu based on the specified array of valid
729    menu items (terminated by V4L2_CTRL_MENU_IDS_END).
730    Use this if there are 'holes' in the list of valid menu items. */
v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu * qmenu,const u32 * ids)731 int v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu *qmenu, const u32 *ids)
732 {
733 	const char **menu_items = v4l2_ctrl_get_menu(qmenu->id);
734 
735 	qmenu->reserved = 0;
736 	if (menu_items == NULL || ids == NULL)
737 		return -EINVAL;
738 	while (*ids != V4L2_CTRL_MENU_IDS_END) {
739 		if (*ids++ == qmenu->index) {
740 			snprintf(qmenu->name, sizeof(qmenu->name),
741 				       menu_items[qmenu->index]);
742 			return 0;
743 		}
744 	}
745 	return -EINVAL;
746 }
747 EXPORT_SYMBOL(v4l2_ctrl_query_menu_valid_items);
748 
749 /* ctrl_classes points to an array of u32 pointers, the last element is
750    a NULL pointer. Each u32 array is a 0-terminated array of control IDs.
751    Each array must be sorted low to high and belong to the same control
752    class. The array of u32 pointer must also be sorted, from low class IDs
753    to high class IDs.
754 
755    This function returns the first ID that follows after the given ID.
756    When no more controls are available 0 is returned. */
v4l2_ctrl_next(const u32 * const * ctrl_classes,u32 id)757 u32 v4l2_ctrl_next(const u32 * const * ctrl_classes, u32 id)
758 {
759 	u32 ctrl_class = V4L2_CTRL_ID2CLASS(id);
760 	const u32 *pctrl;
761 
762 	if (ctrl_classes == NULL)
763 		return 0;
764 
765 	/* if no query is desired, then check if the ID is part of ctrl_classes */
766 	if ((id & V4L2_CTRL_FLAG_NEXT_CTRL) == 0) {
767 		/* find class */
768 		while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) != ctrl_class)
769 			ctrl_classes++;
770 		if (*ctrl_classes == NULL)
771 			return 0;
772 		pctrl = *ctrl_classes;
773 		/* find control ID */
774 		while (*pctrl && *pctrl != id) pctrl++;
775 		return *pctrl ? id : 0;
776 	}
777 	id &= V4L2_CTRL_ID_MASK;
778 	id++;	/* select next control */
779 	/* find first class that matches (or is greater than) the class of
780 	   the ID */
781 	while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) < ctrl_class)
782 		ctrl_classes++;
783 	/* no more classes */
784 	if (*ctrl_classes == NULL)
785 		return 0;
786 	pctrl = *ctrl_classes;
787 	/* find first ctrl within the class that is >= ID */
788 	while (*pctrl && *pctrl < id) pctrl++;
789 	if (*pctrl)
790 		return *pctrl;
791 	/* we are at the end of the controls of the current class. */
792 	/* continue with next class if available */
793 	ctrl_classes++;
794 	if (*ctrl_classes == NULL)
795 		return 0;
796 	return **ctrl_classes;
797 }
798 EXPORT_SYMBOL(v4l2_ctrl_next);
799 
v4l2_chip_match_host(const struct v4l2_dbg_match * match)800 int v4l2_chip_match_host(const struct v4l2_dbg_match *match)
801 {
802 	switch (match->type) {
803 	case V4L2_CHIP_MATCH_HOST:
804 		return match->addr == 0;
805 	default:
806 		return 0;
807 	}
808 }
809 EXPORT_SYMBOL(v4l2_chip_match_host);
810 
811 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
v4l2_chip_match_i2c_client(struct i2c_client * c,const struct v4l2_dbg_match * match)812 int v4l2_chip_match_i2c_client(struct i2c_client *c, const struct v4l2_dbg_match *match)
813 {
814 	int len;
815 
816 	if (c == NULL || match == NULL)
817 		return 0;
818 
819 	switch (match->type) {
820 	case V4L2_CHIP_MATCH_I2C_DRIVER:
821 		if (c->driver == NULL || c->driver->driver.name == NULL)
822 			return 0;
823 		len = strlen(c->driver->driver.name);
824 		/* legacy drivers have a ' suffix, don't try to match that */
825 		if (len && c->driver->driver.name[len - 1] == '\'')
826 			len--;
827 		return len && !strncmp(c->driver->driver.name, match->name, len);
828 	case V4L2_CHIP_MATCH_I2C_ADDR:
829 		return c->addr == match->addr;
830 	default:
831 		return 0;
832 	}
833 }
834 EXPORT_SYMBOL(v4l2_chip_match_i2c_client);
835 
v4l2_chip_ident_i2c_client(struct i2c_client * c,struct v4l2_dbg_chip_ident * chip,u32 ident,u32 revision)836 int v4l2_chip_ident_i2c_client(struct i2c_client *c, struct v4l2_dbg_chip_ident *chip,
837 		u32 ident, u32 revision)
838 {
839 	if (!v4l2_chip_match_i2c_client(c, &chip->match))
840 		return 0;
841 	if (chip->ident == V4L2_IDENT_NONE) {
842 		chip->ident = ident;
843 		chip->revision = revision;
844 	}
845 	else {
846 		chip->ident = V4L2_IDENT_AMBIGUOUS;
847 		chip->revision = 0;
848 	}
849 	return 0;
850 }
851 EXPORT_SYMBOL(v4l2_chip_ident_i2c_client);
852 
853 /* ----------------------------------------------------------------- */
854 
855 /* Helper function for I2C legacy drivers */
856 
v4l2_i2c_attach(struct i2c_adapter * adapter,int address,struct i2c_driver * driver,const char * name,int (* probe)(struct i2c_client *,const struct i2c_device_id *))857 int v4l2_i2c_attach(struct i2c_adapter *adapter, int address, struct i2c_driver *driver,
858 		const char *name,
859 		int (*probe)(struct i2c_client *, const struct i2c_device_id *))
860 {
861 	struct i2c_client *client;
862 	int err;
863 
864 	client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
865 	if (!client)
866 		return -ENOMEM;
867 
868 	client->addr = address;
869 	client->adapter = adapter;
870 	client->driver = driver;
871 	strlcpy(client->name, name, sizeof(client->name));
872 
873 	err = probe(client, NULL);
874 	if (err == 0) {
875 		i2c_attach_client(client);
876 	} else {
877 		kfree(client);
878 	}
879 	return err != -ENOMEM ? 0 : err;
880 }
881 EXPORT_SYMBOL(v4l2_i2c_attach);
882 
v4l2_i2c_subdev_init(struct v4l2_subdev * sd,struct i2c_client * client,const struct v4l2_subdev_ops * ops)883 void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
884 		const struct v4l2_subdev_ops *ops)
885 {
886 	v4l2_subdev_init(sd, ops);
887 	/* the owner is the same as the i2c_client's driver owner */
888 	sd->owner = client->driver->driver.owner;
889 	/* i2c_client and v4l2_subdev point to one another */
890 	v4l2_set_subdevdata(sd, client);
891 	i2c_set_clientdata(client, sd);
892 	/* initialize name */
893 	snprintf(sd->name, sizeof(sd->name), "%s %d-%04x",
894 		client->driver->driver.name, i2c_adapter_id(client->adapter),
895 		client->addr);
896 }
897 EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init);
898 
899 
900 
901 /* Load an i2c sub-device. It assumes that i2c_get_adapdata(adapter)
902    returns the v4l2_device and that i2c_get_clientdata(client)
903    returns the v4l2_subdev. */
v4l2_i2c_new_subdev(struct i2c_adapter * adapter,const char * module_name,const char * client_type,u8 addr)904 struct v4l2_subdev *v4l2_i2c_new_subdev(struct i2c_adapter *adapter,
905 		const char *module_name, const char *client_type, u8 addr)
906 {
907 	struct v4l2_device *dev = i2c_get_adapdata(adapter);
908 	struct v4l2_subdev *sd = NULL;
909 	struct i2c_client *client;
910 	struct i2c_board_info info;
911 
912 	BUG_ON(!dev);
913 #ifdef MODULE
914 	if (module_name)
915 		request_module(module_name);
916 #endif
917 	/* Setup the i2c board info with the device type and
918 	   the device address. */
919 	memset(&info, 0, sizeof(info));
920 	strlcpy(info.type, client_type, sizeof(info.type));
921 	info.addr = addr;
922 
923 	/* Create the i2c client */
924 	client = i2c_new_device(adapter, &info);
925 	/* Note: it is possible in the future that
926 	   c->driver is NULL if the driver is still being loaded.
927 	   We need better support from the kernel so that we
928 	   can easily wait for the load to finish. */
929 	if (client == NULL || client->driver == NULL)
930 		return NULL;
931 
932 	/* Lock the module so we can safely get the v4l2_subdev pointer */
933 	if (!try_module_get(client->driver->driver.owner))
934 		return NULL;
935 	sd = i2c_get_clientdata(client);
936 
937 	/* Register with the v4l2_device which increases the module's
938 	   use count as well. */
939 	if (v4l2_device_register_subdev(dev, sd))
940 		sd = NULL;
941 	/* Decrease the module use count to match the first try_module_get. */
942 	module_put(client->driver->driver.owner);
943 	return sd;
944 
945 }
946 EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev);
947 
948 /* Probe and load an i2c sub-device. It assumes that i2c_get_adapdata(adapter)
949    returns the v4l2_device and that i2c_get_clientdata(client)
950    returns the v4l2_subdev. */
v4l2_i2c_new_probed_subdev(struct i2c_adapter * adapter,const char * module_name,const char * client_type,const unsigned short * addrs)951 struct v4l2_subdev *v4l2_i2c_new_probed_subdev(struct i2c_adapter *adapter,
952 	const char *module_name, const char *client_type,
953 	const unsigned short *addrs)
954 {
955 	struct v4l2_device *dev = i2c_get_adapdata(adapter);
956 	struct v4l2_subdev *sd = NULL;
957 	struct i2c_client *client = NULL;
958 	struct i2c_board_info info;
959 
960 	BUG_ON(!dev);
961 #ifdef MODULE
962 	if (module_name)
963 		request_module(module_name);
964 #endif
965 	/* Setup the i2c board info with the device type and
966 	   the device address. */
967 	memset(&info, 0, sizeof(info));
968 	strlcpy(info.type, client_type, sizeof(info.type));
969 
970 	/* Probe and create the i2c client */
971 	client = i2c_new_probed_device(adapter, &info, addrs);
972 	/* Note: it is possible in the future that
973 	   c->driver is NULL if the driver is still being loaded.
974 	   We need better support from the kernel so that we
975 	   can easily wait for the load to finish. */
976 	if (client == NULL || client->driver == NULL)
977 		return NULL;
978 
979 	/* Lock the module so we can safely get the v4l2_subdev pointer */
980 	if (!try_module_get(client->driver->driver.owner))
981 		return NULL;
982 	sd = i2c_get_clientdata(client);
983 
984 	/* Register with the v4l2_device which increases the module's
985 	   use count as well. */
986 	if (v4l2_device_register_subdev(dev, sd))
987 		sd = NULL;
988 	/* Decrease the module use count to match the first try_module_get. */
989 	module_put(client->driver->driver.owner);
990 	return sd;
991 }
992 EXPORT_SYMBOL_GPL(v4l2_i2c_new_probed_subdev);
993 
994 #endif
995