xref: /linux/drivers/media/i2c/mt9p031.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
1 /*
2  * Driver for MT9P031 CMOS Image Sensor from Aptina
3  *
4  * Copyright (C) 2011, Laurent Pinchart <laurent.pinchart@ideasonboard.com>
5  * Copyright (C) 2011, Javier Martin <javier.martin@vista-silicon.com>
6  * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
7  *
8  * Based on the MT9V032 driver and Bastian Hecht's code.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/clk.h>
16 #include <linux/delay.h>
17 #include <linux/device.h>
18 #include <linux/gpio.h>
19 #include <linux/i2c.h>
20 #include <linux/log2.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_gpio.h>
24 #include <linux/of_graph.h>
25 #include <linux/pm.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/slab.h>
28 #include <linux/videodev2.h>
29 
30 #include <media/mt9p031.h>
31 #include <media/v4l2-ctrls.h>
32 #include <media/v4l2-device.h>
33 #include <media/v4l2-subdev.h>
34 
35 #include "aptina-pll.h"
36 
37 #define MT9P031_PIXEL_ARRAY_WIDTH			2752
38 #define MT9P031_PIXEL_ARRAY_HEIGHT			2004
39 
40 #define MT9P031_CHIP_VERSION				0x00
41 #define		MT9P031_CHIP_VERSION_VALUE		0x1801
42 #define MT9P031_ROW_START				0x01
43 #define		MT9P031_ROW_START_MIN			0
44 #define		MT9P031_ROW_START_MAX			2004
45 #define		MT9P031_ROW_START_DEF			54
46 #define MT9P031_COLUMN_START				0x02
47 #define		MT9P031_COLUMN_START_MIN		0
48 #define		MT9P031_COLUMN_START_MAX		2750
49 #define		MT9P031_COLUMN_START_DEF		16
50 #define MT9P031_WINDOW_HEIGHT				0x03
51 #define		MT9P031_WINDOW_HEIGHT_MIN		2
52 #define		MT9P031_WINDOW_HEIGHT_MAX		2006
53 #define		MT9P031_WINDOW_HEIGHT_DEF		1944
54 #define MT9P031_WINDOW_WIDTH				0x04
55 #define		MT9P031_WINDOW_WIDTH_MIN		2
56 #define		MT9P031_WINDOW_WIDTH_MAX		2752
57 #define		MT9P031_WINDOW_WIDTH_DEF		2592
58 #define MT9P031_HORIZONTAL_BLANK			0x05
59 #define		MT9P031_HORIZONTAL_BLANK_MIN		0
60 #define		MT9P031_HORIZONTAL_BLANK_MAX		4095
61 #define MT9P031_VERTICAL_BLANK				0x06
62 #define		MT9P031_VERTICAL_BLANK_MIN		1
63 #define		MT9P031_VERTICAL_BLANK_MAX		4096
64 #define		MT9P031_VERTICAL_BLANK_DEF		26
65 #define MT9P031_OUTPUT_CONTROL				0x07
66 #define		MT9P031_OUTPUT_CONTROL_CEN		2
67 #define		MT9P031_OUTPUT_CONTROL_SYN		1
68 #define		MT9P031_OUTPUT_CONTROL_DEF		0x1f82
69 #define MT9P031_SHUTTER_WIDTH_UPPER			0x08
70 #define MT9P031_SHUTTER_WIDTH_LOWER			0x09
71 #define		MT9P031_SHUTTER_WIDTH_MIN		1
72 #define		MT9P031_SHUTTER_WIDTH_MAX		1048575
73 #define		MT9P031_SHUTTER_WIDTH_DEF		1943
74 #define	MT9P031_PLL_CONTROL				0x10
75 #define		MT9P031_PLL_CONTROL_PWROFF		0x0050
76 #define		MT9P031_PLL_CONTROL_PWRON		0x0051
77 #define		MT9P031_PLL_CONTROL_USEPLL		0x0052
78 #define	MT9P031_PLL_CONFIG_1				0x11
79 #define	MT9P031_PLL_CONFIG_2				0x12
80 #define MT9P031_PIXEL_CLOCK_CONTROL			0x0a
81 #define		MT9P031_PIXEL_CLOCK_INVERT		(1 << 15)
82 #define		MT9P031_PIXEL_CLOCK_SHIFT(n)		((n) << 8)
83 #define		MT9P031_PIXEL_CLOCK_DIVIDE(n)		((n) << 0)
84 #define MT9P031_FRAME_RESTART				0x0b
85 #define MT9P031_SHUTTER_DELAY				0x0c
86 #define MT9P031_RST					0x0d
87 #define		MT9P031_RST_ENABLE			1
88 #define		MT9P031_RST_DISABLE			0
89 #define MT9P031_READ_MODE_1				0x1e
90 #define MT9P031_READ_MODE_2				0x20
91 #define		MT9P031_READ_MODE_2_ROW_MIR		(1 << 15)
92 #define		MT9P031_READ_MODE_2_COL_MIR		(1 << 14)
93 #define		MT9P031_READ_MODE_2_ROW_BLC		(1 << 6)
94 #define MT9P031_ROW_ADDRESS_MODE			0x22
95 #define MT9P031_COLUMN_ADDRESS_MODE			0x23
96 #define MT9P031_GLOBAL_GAIN				0x35
97 #define		MT9P031_GLOBAL_GAIN_MIN			8
98 #define		MT9P031_GLOBAL_GAIN_MAX			1024
99 #define		MT9P031_GLOBAL_GAIN_DEF			8
100 #define		MT9P031_GLOBAL_GAIN_MULT		(1 << 6)
101 #define MT9P031_ROW_BLACK_TARGET			0x49
102 #define MT9P031_ROW_BLACK_DEF_OFFSET			0x4b
103 #define MT9P031_GREEN1_OFFSET				0x60
104 #define MT9P031_GREEN2_OFFSET				0x61
105 #define MT9P031_BLACK_LEVEL_CALIBRATION			0x62
106 #define		MT9P031_BLC_MANUAL_BLC			(1 << 0)
107 #define MT9P031_RED_OFFSET				0x63
108 #define MT9P031_BLUE_OFFSET				0x64
109 #define MT9P031_TEST_PATTERN				0xa0
110 #define		MT9P031_TEST_PATTERN_SHIFT		3
111 #define		MT9P031_TEST_PATTERN_ENABLE		(1 << 0)
112 #define		MT9P031_TEST_PATTERN_DISABLE		(0 << 0)
113 #define MT9P031_TEST_PATTERN_GREEN			0xa1
114 #define MT9P031_TEST_PATTERN_RED			0xa2
115 #define MT9P031_TEST_PATTERN_BLUE			0xa3
116 
117 enum mt9p031_model {
118 	MT9P031_MODEL_COLOR,
119 	MT9P031_MODEL_MONOCHROME,
120 };
121 
122 struct mt9p031 {
123 	struct v4l2_subdev subdev;
124 	struct media_pad pad;
125 	struct v4l2_rect crop;  /* Sensor window */
126 	struct v4l2_mbus_framefmt format;
127 	struct mt9p031_platform_data *pdata;
128 	struct mutex power_lock; /* lock to protect power_count */
129 	int power_count;
130 
131 	struct clk *clk;
132 	struct regulator_bulk_data regulators[3];
133 
134 	enum mt9p031_model model;
135 	struct aptina_pll pll;
136 	unsigned int clk_div;
137 	bool use_pll;
138 	int reset;
139 
140 	struct v4l2_ctrl_handler ctrls;
141 	struct v4l2_ctrl *blc_auto;
142 	struct v4l2_ctrl *blc_offset;
143 
144 	/* Registers cache */
145 	u16 output_control;
146 	u16 mode2;
147 };
148 
149 static struct mt9p031 *to_mt9p031(struct v4l2_subdev *sd)
150 {
151 	return container_of(sd, struct mt9p031, subdev);
152 }
153 
154 static int mt9p031_read(struct i2c_client *client, u8 reg)
155 {
156 	return i2c_smbus_read_word_swapped(client, reg);
157 }
158 
159 static int mt9p031_write(struct i2c_client *client, u8 reg, u16 data)
160 {
161 	return i2c_smbus_write_word_swapped(client, reg, data);
162 }
163 
164 static int mt9p031_set_output_control(struct mt9p031 *mt9p031, u16 clear,
165 				      u16 set)
166 {
167 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
168 	u16 value = (mt9p031->output_control & ~clear) | set;
169 	int ret;
170 
171 	ret = mt9p031_write(client, MT9P031_OUTPUT_CONTROL, value);
172 	if (ret < 0)
173 		return ret;
174 
175 	mt9p031->output_control = value;
176 	return 0;
177 }
178 
179 static int mt9p031_set_mode2(struct mt9p031 *mt9p031, u16 clear, u16 set)
180 {
181 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
182 	u16 value = (mt9p031->mode2 & ~clear) | set;
183 	int ret;
184 
185 	ret = mt9p031_write(client, MT9P031_READ_MODE_2, value);
186 	if (ret < 0)
187 		return ret;
188 
189 	mt9p031->mode2 = value;
190 	return 0;
191 }
192 
193 static int mt9p031_reset(struct mt9p031 *mt9p031)
194 {
195 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
196 	int ret;
197 
198 	/* Disable chip output, synchronous option update */
199 	ret = mt9p031_write(client, MT9P031_RST, MT9P031_RST_ENABLE);
200 	if (ret < 0)
201 		return ret;
202 	ret = mt9p031_write(client, MT9P031_RST, MT9P031_RST_DISABLE);
203 	if (ret < 0)
204 		return ret;
205 
206 	ret = mt9p031_write(client, MT9P031_PIXEL_CLOCK_CONTROL,
207 			    MT9P031_PIXEL_CLOCK_DIVIDE(mt9p031->clk_div));
208 	if (ret < 0)
209 		return ret;
210 
211 	return mt9p031_set_output_control(mt9p031, MT9P031_OUTPUT_CONTROL_CEN,
212 					  0);
213 }
214 
215 static int mt9p031_clk_setup(struct mt9p031 *mt9p031)
216 {
217 	static const struct aptina_pll_limits limits = {
218 		.ext_clock_min = 6000000,
219 		.ext_clock_max = 27000000,
220 		.int_clock_min = 2000000,
221 		.int_clock_max = 13500000,
222 		.out_clock_min = 180000000,
223 		.out_clock_max = 360000000,
224 		.pix_clock_max = 96000000,
225 		.n_min = 1,
226 		.n_max = 64,
227 		.m_min = 16,
228 		.m_max = 255,
229 		.p1_min = 1,
230 		.p1_max = 128,
231 	};
232 
233 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
234 	struct mt9p031_platform_data *pdata = mt9p031->pdata;
235 	int ret;
236 
237 	mt9p031->clk = devm_clk_get(&client->dev, NULL);
238 	if (IS_ERR(mt9p031->clk))
239 		return PTR_ERR(mt9p031->clk);
240 
241 	ret = clk_set_rate(mt9p031->clk, pdata->ext_freq);
242 	if (ret < 0)
243 		return ret;
244 
245 	/* If the external clock frequency is out of bounds for the PLL use the
246 	 * pixel clock divider only and disable the PLL.
247 	 */
248 	if (pdata->ext_freq > limits.ext_clock_max) {
249 		unsigned int div;
250 
251 		div = DIV_ROUND_UP(pdata->ext_freq, pdata->target_freq);
252 		div = roundup_pow_of_two(div) / 2;
253 
254 		mt9p031->clk_div = max_t(unsigned int, div, 64);
255 		mt9p031->use_pll = false;
256 
257 		return 0;
258 	}
259 
260 	mt9p031->pll.ext_clock = pdata->ext_freq;
261 	mt9p031->pll.pix_clock = pdata->target_freq;
262 	mt9p031->use_pll = true;
263 
264 	return aptina_pll_calculate(&client->dev, &limits, &mt9p031->pll);
265 }
266 
267 static int mt9p031_pll_enable(struct mt9p031 *mt9p031)
268 {
269 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
270 	int ret;
271 
272 	if (!mt9p031->use_pll)
273 		return 0;
274 
275 	ret = mt9p031_write(client, MT9P031_PLL_CONTROL,
276 			    MT9P031_PLL_CONTROL_PWRON);
277 	if (ret < 0)
278 		return ret;
279 
280 	ret = mt9p031_write(client, MT9P031_PLL_CONFIG_1,
281 			    (mt9p031->pll.m << 8) | (mt9p031->pll.n - 1));
282 	if (ret < 0)
283 		return ret;
284 
285 	ret = mt9p031_write(client, MT9P031_PLL_CONFIG_2, mt9p031->pll.p1 - 1);
286 	if (ret < 0)
287 		return ret;
288 
289 	usleep_range(1000, 2000);
290 	ret = mt9p031_write(client, MT9P031_PLL_CONTROL,
291 			    MT9P031_PLL_CONTROL_PWRON |
292 			    MT9P031_PLL_CONTROL_USEPLL);
293 	return ret;
294 }
295 
296 static inline int mt9p031_pll_disable(struct mt9p031 *mt9p031)
297 {
298 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
299 
300 	if (!mt9p031->use_pll)
301 		return 0;
302 
303 	return mt9p031_write(client, MT9P031_PLL_CONTROL,
304 			     MT9P031_PLL_CONTROL_PWROFF);
305 }
306 
307 static int mt9p031_power_on(struct mt9p031 *mt9p031)
308 {
309 	int ret;
310 
311 	/* Ensure RESET_BAR is low */
312 	if (gpio_is_valid(mt9p031->reset)) {
313 		gpio_set_value(mt9p031->reset, 0);
314 		usleep_range(1000, 2000);
315 	}
316 
317 	/* Bring up the supplies */
318 	ret = regulator_bulk_enable(ARRAY_SIZE(mt9p031->regulators),
319 				   mt9p031->regulators);
320 	if (ret < 0)
321 		return ret;
322 
323 	/* Enable clock */
324 	if (mt9p031->clk) {
325 		ret = clk_prepare_enable(mt9p031->clk);
326 		if (ret) {
327 			regulator_bulk_disable(ARRAY_SIZE(mt9p031->regulators),
328 					       mt9p031->regulators);
329 			return ret;
330 		}
331 	}
332 
333 	/* Now RESET_BAR must be high */
334 	if (gpio_is_valid(mt9p031->reset)) {
335 		gpio_set_value(mt9p031->reset, 1);
336 		usleep_range(1000, 2000);
337 	}
338 
339 	return 0;
340 }
341 
342 static void mt9p031_power_off(struct mt9p031 *mt9p031)
343 {
344 	if (gpio_is_valid(mt9p031->reset)) {
345 		gpio_set_value(mt9p031->reset, 0);
346 		usleep_range(1000, 2000);
347 	}
348 
349 	regulator_bulk_disable(ARRAY_SIZE(mt9p031->regulators),
350 			       mt9p031->regulators);
351 
352 	if (mt9p031->clk)
353 		clk_disable_unprepare(mt9p031->clk);
354 }
355 
356 static int __mt9p031_set_power(struct mt9p031 *mt9p031, bool on)
357 {
358 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
359 	int ret;
360 
361 	if (!on) {
362 		mt9p031_power_off(mt9p031);
363 		return 0;
364 	}
365 
366 	ret = mt9p031_power_on(mt9p031);
367 	if (ret < 0)
368 		return ret;
369 
370 	ret = mt9p031_reset(mt9p031);
371 	if (ret < 0) {
372 		dev_err(&client->dev, "Failed to reset the camera\n");
373 		return ret;
374 	}
375 
376 	return v4l2_ctrl_handler_setup(&mt9p031->ctrls);
377 }
378 
379 /* -----------------------------------------------------------------------------
380  * V4L2 subdev video operations
381  */
382 
383 static int mt9p031_set_params(struct mt9p031 *mt9p031)
384 {
385 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
386 	struct v4l2_mbus_framefmt *format = &mt9p031->format;
387 	const struct v4l2_rect *crop = &mt9p031->crop;
388 	unsigned int hblank;
389 	unsigned int vblank;
390 	unsigned int xskip;
391 	unsigned int yskip;
392 	unsigned int xbin;
393 	unsigned int ybin;
394 	int ret;
395 
396 	/* Windows position and size.
397 	 *
398 	 * TODO: Make sure the start coordinates and window size match the
399 	 * skipping, binning and mirroring (see description of registers 2 and 4
400 	 * in table 13, and Binning section on page 41).
401 	 */
402 	ret = mt9p031_write(client, MT9P031_COLUMN_START, crop->left);
403 	if (ret < 0)
404 		return ret;
405 	ret = mt9p031_write(client, MT9P031_ROW_START, crop->top);
406 	if (ret < 0)
407 		return ret;
408 	ret = mt9p031_write(client, MT9P031_WINDOW_WIDTH, crop->width - 1);
409 	if (ret < 0)
410 		return ret;
411 	ret = mt9p031_write(client, MT9P031_WINDOW_HEIGHT, crop->height - 1);
412 	if (ret < 0)
413 		return ret;
414 
415 	/* Row and column binning and skipping. Use the maximum binning value
416 	 * compatible with the skipping settings.
417 	 */
418 	xskip = DIV_ROUND_CLOSEST(crop->width, format->width);
419 	yskip = DIV_ROUND_CLOSEST(crop->height, format->height);
420 	xbin = 1 << (ffs(xskip) - 1);
421 	ybin = 1 << (ffs(yskip) - 1);
422 
423 	ret = mt9p031_write(client, MT9P031_COLUMN_ADDRESS_MODE,
424 			    ((xbin - 1) << 4) | (xskip - 1));
425 	if (ret < 0)
426 		return ret;
427 	ret = mt9p031_write(client, MT9P031_ROW_ADDRESS_MODE,
428 			    ((ybin - 1) << 4) | (yskip - 1));
429 	if (ret < 0)
430 		return ret;
431 
432 	/* Blanking - use minimum value for horizontal blanking and default
433 	 * value for vertical blanking.
434 	 */
435 	hblank = 346 * ybin + 64 + (80 >> min_t(unsigned int, xbin, 3));
436 	vblank = MT9P031_VERTICAL_BLANK_DEF;
437 
438 	ret = mt9p031_write(client, MT9P031_HORIZONTAL_BLANK, hblank - 1);
439 	if (ret < 0)
440 		return ret;
441 	ret = mt9p031_write(client, MT9P031_VERTICAL_BLANK, vblank - 1);
442 	if (ret < 0)
443 		return ret;
444 
445 	return ret;
446 }
447 
448 static int mt9p031_s_stream(struct v4l2_subdev *subdev, int enable)
449 {
450 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
451 	int ret;
452 
453 	if (!enable) {
454 		/* Stop sensor readout */
455 		ret = mt9p031_set_output_control(mt9p031,
456 						 MT9P031_OUTPUT_CONTROL_CEN, 0);
457 		if (ret < 0)
458 			return ret;
459 
460 		return mt9p031_pll_disable(mt9p031);
461 	}
462 
463 	ret = mt9p031_set_params(mt9p031);
464 	if (ret < 0)
465 		return ret;
466 
467 	/* Switch to master "normal" mode */
468 	ret = mt9p031_set_output_control(mt9p031, 0,
469 					 MT9P031_OUTPUT_CONTROL_CEN);
470 	if (ret < 0)
471 		return ret;
472 
473 	return mt9p031_pll_enable(mt9p031);
474 }
475 
476 static int mt9p031_enum_mbus_code(struct v4l2_subdev *subdev,
477 				  struct v4l2_subdev_fh *fh,
478 				  struct v4l2_subdev_mbus_code_enum *code)
479 {
480 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
481 
482 	if (code->pad || code->index)
483 		return -EINVAL;
484 
485 	code->code = mt9p031->format.code;
486 	return 0;
487 }
488 
489 static int mt9p031_enum_frame_size(struct v4l2_subdev *subdev,
490 				   struct v4l2_subdev_fh *fh,
491 				   struct v4l2_subdev_frame_size_enum *fse)
492 {
493 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
494 
495 	if (fse->index >= 8 || fse->code != mt9p031->format.code)
496 		return -EINVAL;
497 
498 	fse->min_width = MT9P031_WINDOW_WIDTH_DEF
499 		       / min_t(unsigned int, 7, fse->index + 1);
500 	fse->max_width = fse->min_width;
501 	fse->min_height = MT9P031_WINDOW_HEIGHT_DEF / (fse->index + 1);
502 	fse->max_height = fse->min_height;
503 
504 	return 0;
505 }
506 
507 static struct v4l2_mbus_framefmt *
508 __mt9p031_get_pad_format(struct mt9p031 *mt9p031, struct v4l2_subdev_fh *fh,
509 			 unsigned int pad, u32 which)
510 {
511 	switch (which) {
512 	case V4L2_SUBDEV_FORMAT_TRY:
513 		return v4l2_subdev_get_try_format(fh, pad);
514 	case V4L2_SUBDEV_FORMAT_ACTIVE:
515 		return &mt9p031->format;
516 	default:
517 		return NULL;
518 	}
519 }
520 
521 static struct v4l2_rect *
522 __mt9p031_get_pad_crop(struct mt9p031 *mt9p031, struct v4l2_subdev_fh *fh,
523 		     unsigned int pad, u32 which)
524 {
525 	switch (which) {
526 	case V4L2_SUBDEV_FORMAT_TRY:
527 		return v4l2_subdev_get_try_crop(fh, pad);
528 	case V4L2_SUBDEV_FORMAT_ACTIVE:
529 		return &mt9p031->crop;
530 	default:
531 		return NULL;
532 	}
533 }
534 
535 static int mt9p031_get_format(struct v4l2_subdev *subdev,
536 			      struct v4l2_subdev_fh *fh,
537 			      struct v4l2_subdev_format *fmt)
538 {
539 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
540 
541 	fmt->format = *__mt9p031_get_pad_format(mt9p031, fh, fmt->pad,
542 						fmt->which);
543 	return 0;
544 }
545 
546 static int mt9p031_set_format(struct v4l2_subdev *subdev,
547 			      struct v4l2_subdev_fh *fh,
548 			      struct v4l2_subdev_format *format)
549 {
550 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
551 	struct v4l2_mbus_framefmt *__format;
552 	struct v4l2_rect *__crop;
553 	unsigned int width;
554 	unsigned int height;
555 	unsigned int hratio;
556 	unsigned int vratio;
557 
558 	__crop = __mt9p031_get_pad_crop(mt9p031, fh, format->pad,
559 					format->which);
560 
561 	/* Clamp the width and height to avoid dividing by zero. */
562 	width = clamp_t(unsigned int, ALIGN(format->format.width, 2),
563 			max_t(unsigned int, __crop->width / 7,
564 			      MT9P031_WINDOW_WIDTH_MIN),
565 			__crop->width);
566 	height = clamp_t(unsigned int, ALIGN(format->format.height, 2),
567 			 max_t(unsigned int, __crop->height / 8,
568 			       MT9P031_WINDOW_HEIGHT_MIN),
569 			 __crop->height);
570 
571 	hratio = DIV_ROUND_CLOSEST(__crop->width, width);
572 	vratio = DIV_ROUND_CLOSEST(__crop->height, height);
573 
574 	__format = __mt9p031_get_pad_format(mt9p031, fh, format->pad,
575 					    format->which);
576 	__format->width = __crop->width / hratio;
577 	__format->height = __crop->height / vratio;
578 
579 	format->format = *__format;
580 
581 	return 0;
582 }
583 
584 static int mt9p031_get_crop(struct v4l2_subdev *subdev,
585 			    struct v4l2_subdev_fh *fh,
586 			    struct v4l2_subdev_crop *crop)
587 {
588 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
589 
590 	crop->rect = *__mt9p031_get_pad_crop(mt9p031, fh, crop->pad,
591 					     crop->which);
592 	return 0;
593 }
594 
595 static int mt9p031_set_crop(struct v4l2_subdev *subdev,
596 			    struct v4l2_subdev_fh *fh,
597 			    struct v4l2_subdev_crop *crop)
598 {
599 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
600 	struct v4l2_mbus_framefmt *__format;
601 	struct v4l2_rect *__crop;
602 	struct v4l2_rect rect;
603 
604 	/* Clamp the crop rectangle boundaries and align them to a multiple of 2
605 	 * pixels to ensure a GRBG Bayer pattern.
606 	 */
607 	rect.left = clamp(ALIGN(crop->rect.left, 2), MT9P031_COLUMN_START_MIN,
608 			  MT9P031_COLUMN_START_MAX);
609 	rect.top = clamp(ALIGN(crop->rect.top, 2), MT9P031_ROW_START_MIN,
610 			 MT9P031_ROW_START_MAX);
611 	rect.width = clamp_t(unsigned int, ALIGN(crop->rect.width, 2),
612 			     MT9P031_WINDOW_WIDTH_MIN,
613 			     MT9P031_WINDOW_WIDTH_MAX);
614 	rect.height = clamp_t(unsigned int, ALIGN(crop->rect.height, 2),
615 			      MT9P031_WINDOW_HEIGHT_MIN,
616 			      MT9P031_WINDOW_HEIGHT_MAX);
617 
618 	rect.width = min_t(unsigned int, rect.width,
619 			   MT9P031_PIXEL_ARRAY_WIDTH - rect.left);
620 	rect.height = min_t(unsigned int, rect.height,
621 			    MT9P031_PIXEL_ARRAY_HEIGHT - rect.top);
622 
623 	__crop = __mt9p031_get_pad_crop(mt9p031, fh, crop->pad, crop->which);
624 
625 	if (rect.width != __crop->width || rect.height != __crop->height) {
626 		/* Reset the output image size if the crop rectangle size has
627 		 * been modified.
628 		 */
629 		__format = __mt9p031_get_pad_format(mt9p031, fh, crop->pad,
630 						    crop->which);
631 		__format->width = rect.width;
632 		__format->height = rect.height;
633 	}
634 
635 	*__crop = rect;
636 	crop->rect = rect;
637 
638 	return 0;
639 }
640 
641 /* -----------------------------------------------------------------------------
642  * V4L2 subdev control operations
643  */
644 
645 #define V4L2_CID_BLC_AUTO		(V4L2_CID_USER_BASE | 0x1002)
646 #define V4L2_CID_BLC_TARGET_LEVEL	(V4L2_CID_USER_BASE | 0x1003)
647 #define V4L2_CID_BLC_ANALOG_OFFSET	(V4L2_CID_USER_BASE | 0x1004)
648 #define V4L2_CID_BLC_DIGITAL_OFFSET	(V4L2_CID_USER_BASE | 0x1005)
649 
650 static int mt9p031_restore_blc(struct mt9p031 *mt9p031)
651 {
652 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
653 	int ret;
654 
655 	if (mt9p031->blc_auto->cur.val != 0) {
656 		ret = mt9p031_set_mode2(mt9p031, 0,
657 					MT9P031_READ_MODE_2_ROW_BLC);
658 		if (ret < 0)
659 			return ret;
660 	}
661 
662 	if (mt9p031->blc_offset->cur.val != 0) {
663 		ret = mt9p031_write(client, MT9P031_ROW_BLACK_TARGET,
664 				    mt9p031->blc_offset->cur.val);
665 		if (ret < 0)
666 			return ret;
667 	}
668 
669 	return 0;
670 }
671 
672 static int mt9p031_s_ctrl(struct v4l2_ctrl *ctrl)
673 {
674 	struct mt9p031 *mt9p031 =
675 			container_of(ctrl->handler, struct mt9p031, ctrls);
676 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
677 	u16 data;
678 	int ret;
679 
680 	if (ctrl->flags & V4L2_CTRL_FLAG_INACTIVE)
681 		return 0;
682 
683 	switch (ctrl->id) {
684 	case V4L2_CID_EXPOSURE:
685 		ret = mt9p031_write(client, MT9P031_SHUTTER_WIDTH_UPPER,
686 				    (ctrl->val >> 16) & 0xffff);
687 		if (ret < 0)
688 			return ret;
689 
690 		return mt9p031_write(client, MT9P031_SHUTTER_WIDTH_LOWER,
691 				     ctrl->val & 0xffff);
692 
693 	case V4L2_CID_GAIN:
694 		/* Gain is controlled by 2 analog stages and a digital stage.
695 		 * Valid values for the 3 stages are
696 		 *
697 		 * Stage                Min     Max     Step
698 		 * ------------------------------------------
699 		 * First analog stage   x1      x2      1
700 		 * Second analog stage  x1      x4      0.125
701 		 * Digital stage        x1      x16     0.125
702 		 *
703 		 * To minimize noise, the gain stages should be used in the
704 		 * second analog stage, first analog stage, digital stage order.
705 		 * Gain from a previous stage should be pushed to its maximum
706 		 * value before the next stage is used.
707 		 */
708 		if (ctrl->val <= 32) {
709 			data = ctrl->val;
710 		} else if (ctrl->val <= 64) {
711 			ctrl->val &= ~1;
712 			data = (1 << 6) | (ctrl->val >> 1);
713 		} else {
714 			ctrl->val &= ~7;
715 			data = ((ctrl->val - 64) << 5) | (1 << 6) | 32;
716 		}
717 
718 		return mt9p031_write(client, MT9P031_GLOBAL_GAIN, data);
719 
720 	case V4L2_CID_HFLIP:
721 		if (ctrl->val)
722 			return mt9p031_set_mode2(mt9p031,
723 					0, MT9P031_READ_MODE_2_COL_MIR);
724 		else
725 			return mt9p031_set_mode2(mt9p031,
726 					MT9P031_READ_MODE_2_COL_MIR, 0);
727 
728 	case V4L2_CID_VFLIP:
729 		if (ctrl->val)
730 			return mt9p031_set_mode2(mt9p031,
731 					0, MT9P031_READ_MODE_2_ROW_MIR);
732 		else
733 			return mt9p031_set_mode2(mt9p031,
734 					MT9P031_READ_MODE_2_ROW_MIR, 0);
735 
736 	case V4L2_CID_TEST_PATTERN:
737 		/* The digital side of the Black Level Calibration function must
738 		 * be disabled when generating a test pattern to avoid artifacts
739 		 * in the image. Activate (deactivate) the BLC-related controls
740 		 * when the test pattern is enabled (disabled).
741 		 */
742 		v4l2_ctrl_activate(mt9p031->blc_auto, ctrl->val == 0);
743 		v4l2_ctrl_activate(mt9p031->blc_offset, ctrl->val == 0);
744 
745 		if (!ctrl->val) {
746 			/* Restore the BLC settings. */
747 			ret = mt9p031_restore_blc(mt9p031);
748 			if (ret < 0)
749 				return ret;
750 
751 			return mt9p031_write(client, MT9P031_TEST_PATTERN,
752 					     MT9P031_TEST_PATTERN_DISABLE);
753 		}
754 
755 		ret = mt9p031_write(client, MT9P031_TEST_PATTERN_GREEN, 0x05a0);
756 		if (ret < 0)
757 			return ret;
758 		ret = mt9p031_write(client, MT9P031_TEST_PATTERN_RED, 0x0a50);
759 		if (ret < 0)
760 			return ret;
761 		ret = mt9p031_write(client, MT9P031_TEST_PATTERN_BLUE, 0x0aa0);
762 		if (ret < 0)
763 			return ret;
764 
765 		/* Disable digital BLC when generating a test pattern. */
766 		ret = mt9p031_set_mode2(mt9p031, MT9P031_READ_MODE_2_ROW_BLC,
767 					0);
768 		if (ret < 0)
769 			return ret;
770 
771 		ret = mt9p031_write(client, MT9P031_ROW_BLACK_DEF_OFFSET, 0);
772 		if (ret < 0)
773 			return ret;
774 
775 		return mt9p031_write(client, MT9P031_TEST_PATTERN,
776 				((ctrl->val - 1) << MT9P031_TEST_PATTERN_SHIFT)
777 				| MT9P031_TEST_PATTERN_ENABLE);
778 
779 	case V4L2_CID_BLC_AUTO:
780 		ret = mt9p031_set_mode2(mt9p031,
781 				ctrl->val ? 0 : MT9P031_READ_MODE_2_ROW_BLC,
782 				ctrl->val ? MT9P031_READ_MODE_2_ROW_BLC : 0);
783 		if (ret < 0)
784 			return ret;
785 
786 		return mt9p031_write(client, MT9P031_BLACK_LEVEL_CALIBRATION,
787 				     ctrl->val ? 0 : MT9P031_BLC_MANUAL_BLC);
788 
789 	case V4L2_CID_BLC_TARGET_LEVEL:
790 		return mt9p031_write(client, MT9P031_ROW_BLACK_TARGET,
791 				     ctrl->val);
792 
793 	case V4L2_CID_BLC_ANALOG_OFFSET:
794 		data = ctrl->val & ((1 << 9) - 1);
795 
796 		ret = mt9p031_write(client, MT9P031_GREEN1_OFFSET, data);
797 		if (ret < 0)
798 			return ret;
799 		ret = mt9p031_write(client, MT9P031_GREEN2_OFFSET, data);
800 		if (ret < 0)
801 			return ret;
802 		ret = mt9p031_write(client, MT9P031_RED_OFFSET, data);
803 		if (ret < 0)
804 			return ret;
805 		return mt9p031_write(client, MT9P031_BLUE_OFFSET, data);
806 
807 	case V4L2_CID_BLC_DIGITAL_OFFSET:
808 		return mt9p031_write(client, MT9P031_ROW_BLACK_DEF_OFFSET,
809 				     ctrl->val & ((1 << 12) - 1));
810 	}
811 
812 	return 0;
813 }
814 
815 static struct v4l2_ctrl_ops mt9p031_ctrl_ops = {
816 	.s_ctrl = mt9p031_s_ctrl,
817 };
818 
819 static const char * const mt9p031_test_pattern_menu[] = {
820 	"Disabled",
821 	"Color Field",
822 	"Horizontal Gradient",
823 	"Vertical Gradient",
824 	"Diagonal Gradient",
825 	"Classic Test Pattern",
826 	"Walking 1s",
827 	"Monochrome Horizontal Bars",
828 	"Monochrome Vertical Bars",
829 	"Vertical Color Bars",
830 };
831 
832 static const struct v4l2_ctrl_config mt9p031_ctrls[] = {
833 	{
834 		.ops		= &mt9p031_ctrl_ops,
835 		.id		= V4L2_CID_BLC_AUTO,
836 		.type		= V4L2_CTRL_TYPE_BOOLEAN,
837 		.name		= "BLC, Auto",
838 		.min		= 0,
839 		.max		= 1,
840 		.step		= 1,
841 		.def		= 1,
842 		.flags		= 0,
843 	}, {
844 		.ops		= &mt9p031_ctrl_ops,
845 		.id		= V4L2_CID_BLC_TARGET_LEVEL,
846 		.type		= V4L2_CTRL_TYPE_INTEGER,
847 		.name		= "BLC Target Level",
848 		.min		= 0,
849 		.max		= 4095,
850 		.step		= 1,
851 		.def		= 168,
852 		.flags		= 0,
853 	}, {
854 		.ops		= &mt9p031_ctrl_ops,
855 		.id		= V4L2_CID_BLC_ANALOG_OFFSET,
856 		.type		= V4L2_CTRL_TYPE_INTEGER,
857 		.name		= "BLC Analog Offset",
858 		.min		= -255,
859 		.max		= 255,
860 		.step		= 1,
861 		.def		= 32,
862 		.flags		= 0,
863 	}, {
864 		.ops		= &mt9p031_ctrl_ops,
865 		.id		= V4L2_CID_BLC_DIGITAL_OFFSET,
866 		.type		= V4L2_CTRL_TYPE_INTEGER,
867 		.name		= "BLC Digital Offset",
868 		.min		= -2048,
869 		.max		= 2047,
870 		.step		= 1,
871 		.def		= 40,
872 		.flags		= 0,
873 	}
874 };
875 
876 /* -----------------------------------------------------------------------------
877  * V4L2 subdev core operations
878  */
879 
880 static int mt9p031_set_power(struct v4l2_subdev *subdev, int on)
881 {
882 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
883 	int ret = 0;
884 
885 	mutex_lock(&mt9p031->power_lock);
886 
887 	/* If the power count is modified from 0 to != 0 or from != 0 to 0,
888 	 * update the power state.
889 	 */
890 	if (mt9p031->power_count == !on) {
891 		ret = __mt9p031_set_power(mt9p031, !!on);
892 		if (ret < 0)
893 			goto out;
894 	}
895 
896 	/* Update the power count. */
897 	mt9p031->power_count += on ? 1 : -1;
898 	WARN_ON(mt9p031->power_count < 0);
899 
900 out:
901 	mutex_unlock(&mt9p031->power_lock);
902 	return ret;
903 }
904 
905 /* -----------------------------------------------------------------------------
906  * V4L2 subdev internal operations
907  */
908 
909 static int mt9p031_registered(struct v4l2_subdev *subdev)
910 {
911 	struct i2c_client *client = v4l2_get_subdevdata(subdev);
912 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
913 	s32 data;
914 	int ret;
915 
916 	ret = mt9p031_power_on(mt9p031);
917 	if (ret < 0) {
918 		dev_err(&client->dev, "MT9P031 power up failed\n");
919 		return ret;
920 	}
921 
922 	/* Read out the chip version register */
923 	data = mt9p031_read(client, MT9P031_CHIP_VERSION);
924 	mt9p031_power_off(mt9p031);
925 
926 	if (data != MT9P031_CHIP_VERSION_VALUE) {
927 		dev_err(&client->dev, "MT9P031 not detected, wrong version "
928 			"0x%04x\n", data);
929 		return -ENODEV;
930 	}
931 
932 	dev_info(&client->dev, "MT9P031 detected at address 0x%02x\n",
933 		 client->addr);
934 
935 	return 0;
936 }
937 
938 static int mt9p031_open(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
939 {
940 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
941 	struct v4l2_mbus_framefmt *format;
942 	struct v4l2_rect *crop;
943 
944 	crop = v4l2_subdev_get_try_crop(fh, 0);
945 	crop->left = MT9P031_COLUMN_START_DEF;
946 	crop->top = MT9P031_ROW_START_DEF;
947 	crop->width = MT9P031_WINDOW_WIDTH_DEF;
948 	crop->height = MT9P031_WINDOW_HEIGHT_DEF;
949 
950 	format = v4l2_subdev_get_try_format(fh, 0);
951 
952 	if (mt9p031->model == MT9P031_MODEL_MONOCHROME)
953 		format->code = MEDIA_BUS_FMT_Y12_1X12;
954 	else
955 		format->code = MEDIA_BUS_FMT_SGRBG12_1X12;
956 
957 	format->width = MT9P031_WINDOW_WIDTH_DEF;
958 	format->height = MT9P031_WINDOW_HEIGHT_DEF;
959 	format->field = V4L2_FIELD_NONE;
960 	format->colorspace = V4L2_COLORSPACE_SRGB;
961 
962 	return mt9p031_set_power(subdev, 1);
963 }
964 
965 static int mt9p031_close(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
966 {
967 	return mt9p031_set_power(subdev, 0);
968 }
969 
970 static struct v4l2_subdev_core_ops mt9p031_subdev_core_ops = {
971 	.s_power        = mt9p031_set_power,
972 };
973 
974 static struct v4l2_subdev_video_ops mt9p031_subdev_video_ops = {
975 	.s_stream       = mt9p031_s_stream,
976 };
977 
978 static struct v4l2_subdev_pad_ops mt9p031_subdev_pad_ops = {
979 	.enum_mbus_code = mt9p031_enum_mbus_code,
980 	.enum_frame_size = mt9p031_enum_frame_size,
981 	.get_fmt = mt9p031_get_format,
982 	.set_fmt = mt9p031_set_format,
983 	.get_crop = mt9p031_get_crop,
984 	.set_crop = mt9p031_set_crop,
985 };
986 
987 static struct v4l2_subdev_ops mt9p031_subdev_ops = {
988 	.core   = &mt9p031_subdev_core_ops,
989 	.video  = &mt9p031_subdev_video_ops,
990 	.pad    = &mt9p031_subdev_pad_ops,
991 };
992 
993 static const struct v4l2_subdev_internal_ops mt9p031_subdev_internal_ops = {
994 	.registered = mt9p031_registered,
995 	.open = mt9p031_open,
996 	.close = mt9p031_close,
997 };
998 
999 /* -----------------------------------------------------------------------------
1000  * Driver initialization and probing
1001  */
1002 
1003 static struct mt9p031_platform_data *
1004 mt9p031_get_pdata(struct i2c_client *client)
1005 {
1006 	struct mt9p031_platform_data *pdata;
1007 	struct device_node *np;
1008 
1009 	if (!IS_ENABLED(CONFIG_OF) || !client->dev.of_node)
1010 		return client->dev.platform_data;
1011 
1012 	np = of_graph_get_next_endpoint(client->dev.of_node, NULL);
1013 	if (!np)
1014 		return NULL;
1015 
1016 	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
1017 	if (!pdata)
1018 		goto done;
1019 
1020 	pdata->reset = of_get_named_gpio(client->dev.of_node, "reset-gpios", 0);
1021 	of_property_read_u32(np, "input-clock-frequency", &pdata->ext_freq);
1022 	of_property_read_u32(np, "pixel-clock-frequency", &pdata->target_freq);
1023 
1024 done:
1025 	of_node_put(np);
1026 	return pdata;
1027 }
1028 
1029 static int mt9p031_probe(struct i2c_client *client,
1030 			 const struct i2c_device_id *did)
1031 {
1032 	struct mt9p031_platform_data *pdata = mt9p031_get_pdata(client);
1033 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
1034 	struct mt9p031 *mt9p031;
1035 	unsigned int i;
1036 	int ret;
1037 
1038 	if (pdata == NULL) {
1039 		dev_err(&client->dev, "No platform data\n");
1040 		return -EINVAL;
1041 	}
1042 
1043 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
1044 		dev_warn(&client->dev,
1045 			"I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
1046 		return -EIO;
1047 	}
1048 
1049 	mt9p031 = devm_kzalloc(&client->dev, sizeof(*mt9p031), GFP_KERNEL);
1050 	if (mt9p031 == NULL)
1051 		return -ENOMEM;
1052 
1053 	mt9p031->pdata = pdata;
1054 	mt9p031->output_control	= MT9P031_OUTPUT_CONTROL_DEF;
1055 	mt9p031->mode2 = MT9P031_READ_MODE_2_ROW_BLC;
1056 	mt9p031->model = did->driver_data;
1057 	mt9p031->reset = -1;
1058 
1059 	mt9p031->regulators[0].supply = "vdd";
1060 	mt9p031->regulators[1].supply = "vdd_io";
1061 	mt9p031->regulators[2].supply = "vaa";
1062 
1063 	ret = devm_regulator_bulk_get(&client->dev, 3, mt9p031->regulators);
1064 	if (ret < 0) {
1065 		dev_err(&client->dev, "Unable to get regulators\n");
1066 		return ret;
1067 	}
1068 
1069 	v4l2_ctrl_handler_init(&mt9p031->ctrls, ARRAY_SIZE(mt9p031_ctrls) + 6);
1070 
1071 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1072 			  V4L2_CID_EXPOSURE, MT9P031_SHUTTER_WIDTH_MIN,
1073 			  MT9P031_SHUTTER_WIDTH_MAX, 1,
1074 			  MT9P031_SHUTTER_WIDTH_DEF);
1075 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1076 			  V4L2_CID_GAIN, MT9P031_GLOBAL_GAIN_MIN,
1077 			  MT9P031_GLOBAL_GAIN_MAX, 1, MT9P031_GLOBAL_GAIN_DEF);
1078 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1079 			  V4L2_CID_HFLIP, 0, 1, 1, 0);
1080 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1081 			  V4L2_CID_VFLIP, 0, 1, 1, 0);
1082 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1083 			  V4L2_CID_PIXEL_RATE, pdata->target_freq,
1084 			  pdata->target_freq, 1, pdata->target_freq);
1085 	v4l2_ctrl_new_std_menu_items(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1086 			  V4L2_CID_TEST_PATTERN,
1087 			  ARRAY_SIZE(mt9p031_test_pattern_menu) - 1, 0,
1088 			  0, mt9p031_test_pattern_menu);
1089 
1090 	for (i = 0; i < ARRAY_SIZE(mt9p031_ctrls); ++i)
1091 		v4l2_ctrl_new_custom(&mt9p031->ctrls, &mt9p031_ctrls[i], NULL);
1092 
1093 	mt9p031->subdev.ctrl_handler = &mt9p031->ctrls;
1094 
1095 	if (mt9p031->ctrls.error) {
1096 		printk(KERN_INFO "%s: control initialization error %d\n",
1097 		       __func__, mt9p031->ctrls.error);
1098 		ret = mt9p031->ctrls.error;
1099 		goto done;
1100 	}
1101 
1102 	mt9p031->blc_auto = v4l2_ctrl_find(&mt9p031->ctrls, V4L2_CID_BLC_AUTO);
1103 	mt9p031->blc_offset = v4l2_ctrl_find(&mt9p031->ctrls,
1104 					     V4L2_CID_BLC_DIGITAL_OFFSET);
1105 
1106 	mutex_init(&mt9p031->power_lock);
1107 	v4l2_i2c_subdev_init(&mt9p031->subdev, client, &mt9p031_subdev_ops);
1108 	mt9p031->subdev.internal_ops = &mt9p031_subdev_internal_ops;
1109 
1110 	mt9p031->pad.flags = MEDIA_PAD_FL_SOURCE;
1111 	ret = media_entity_init(&mt9p031->subdev.entity, 1, &mt9p031->pad, 0);
1112 	if (ret < 0)
1113 		goto done;
1114 
1115 	mt9p031->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
1116 
1117 	mt9p031->crop.width = MT9P031_WINDOW_WIDTH_DEF;
1118 	mt9p031->crop.height = MT9P031_WINDOW_HEIGHT_DEF;
1119 	mt9p031->crop.left = MT9P031_COLUMN_START_DEF;
1120 	mt9p031->crop.top = MT9P031_ROW_START_DEF;
1121 
1122 	if (mt9p031->model == MT9P031_MODEL_MONOCHROME)
1123 		mt9p031->format.code = MEDIA_BUS_FMT_Y12_1X12;
1124 	else
1125 		mt9p031->format.code = MEDIA_BUS_FMT_SGRBG12_1X12;
1126 
1127 	mt9p031->format.width = MT9P031_WINDOW_WIDTH_DEF;
1128 	mt9p031->format.height = MT9P031_WINDOW_HEIGHT_DEF;
1129 	mt9p031->format.field = V4L2_FIELD_NONE;
1130 	mt9p031->format.colorspace = V4L2_COLORSPACE_SRGB;
1131 
1132 	if (gpio_is_valid(pdata->reset)) {
1133 		ret = devm_gpio_request_one(&client->dev, pdata->reset,
1134 					    GPIOF_OUT_INIT_LOW, "mt9p031_rst");
1135 		if (ret < 0)
1136 			goto done;
1137 
1138 		mt9p031->reset = pdata->reset;
1139 	}
1140 
1141 	ret = mt9p031_clk_setup(mt9p031);
1142 
1143 done:
1144 	if (ret < 0) {
1145 		v4l2_ctrl_handler_free(&mt9p031->ctrls);
1146 		media_entity_cleanup(&mt9p031->subdev.entity);
1147 	}
1148 
1149 	return ret;
1150 }
1151 
1152 static int mt9p031_remove(struct i2c_client *client)
1153 {
1154 	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
1155 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
1156 
1157 	v4l2_ctrl_handler_free(&mt9p031->ctrls);
1158 	v4l2_device_unregister_subdev(subdev);
1159 	media_entity_cleanup(&subdev->entity);
1160 
1161 	return 0;
1162 }
1163 
1164 static const struct i2c_device_id mt9p031_id[] = {
1165 	{ "mt9p031", MT9P031_MODEL_COLOR },
1166 	{ "mt9p031m", MT9P031_MODEL_MONOCHROME },
1167 	{ }
1168 };
1169 MODULE_DEVICE_TABLE(i2c, mt9p031_id);
1170 
1171 #if IS_ENABLED(CONFIG_OF)
1172 static const struct of_device_id mt9p031_of_match[] = {
1173 	{ .compatible = "aptina,mt9p031", },
1174 	{ .compatible = "aptina,mt9p031m", },
1175 	{ /* sentinel */ },
1176 };
1177 MODULE_DEVICE_TABLE(of, mt9p031_of_match);
1178 #endif
1179 
1180 static struct i2c_driver mt9p031_i2c_driver = {
1181 	.driver = {
1182 		.of_match_table = of_match_ptr(mt9p031_of_match),
1183 		.name = "mt9p031",
1184 	},
1185 	.probe          = mt9p031_probe,
1186 	.remove         = mt9p031_remove,
1187 	.id_table       = mt9p031_id,
1188 };
1189 
1190 module_i2c_driver(mt9p031_i2c_driver);
1191 
1192 MODULE_DESCRIPTION("Aptina MT9P031 Camera driver");
1193 MODULE_AUTHOR("Bastian Hecht <hechtb@gmail.com>");
1194 MODULE_LICENSE("GPL v2");
1195