xref: /openbmc/linux/drivers/media/i2c/mt9p031.c (revision 92fa766b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for MT9P031 CMOS Image Sensor from Aptina
4  *
5  * Copyright (C) 2011, Laurent Pinchart <laurent.pinchart@ideasonboard.com>
6  * Copyright (C) 2011, Javier Martin <javier.martin@vista-silicon.com>
7  * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
8  *
9  * Based on the MT9V032 driver and Bastian Hecht's code.
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/i2c.h>
17 #include <linux/log2.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_graph.h>
21 #include <linux/pm.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/slab.h>
24 #include <linux/videodev2.h>
25 
26 #include <media/i2c/mt9p031.h>
27 #include <media/v4l2-async.h>
28 #include <media/v4l2-ctrls.h>
29 #include <media/v4l2-device.h>
30 #include <media/v4l2-fwnode.h>
31 #include <media/v4l2-subdev.h>
32 
33 #include "aptina-pll.h"
34 
35 #define MT9P031_PIXEL_ARRAY_WIDTH			2752
36 #define MT9P031_PIXEL_ARRAY_HEIGHT			2004
37 
38 #define MT9P031_CHIP_VERSION				0x00
39 #define		MT9P031_CHIP_VERSION_VALUE		0x1801
40 #define MT9P031_ROW_START				0x01
41 #define		MT9P031_ROW_START_MIN			0
42 #define		MT9P031_ROW_START_MAX			2004
43 #define		MT9P031_ROW_START_DEF			54
44 #define MT9P031_COLUMN_START				0x02
45 #define		MT9P031_COLUMN_START_MIN		0
46 #define		MT9P031_COLUMN_START_MAX		2750
47 #define		MT9P031_COLUMN_START_DEF		16
48 #define MT9P031_WINDOW_HEIGHT				0x03
49 #define		MT9P031_WINDOW_HEIGHT_MIN		2
50 #define		MT9P031_WINDOW_HEIGHT_MAX		2006
51 #define		MT9P031_WINDOW_HEIGHT_DEF		1944
52 #define MT9P031_WINDOW_WIDTH				0x04
53 #define		MT9P031_WINDOW_WIDTH_MIN		2
54 #define		MT9P031_WINDOW_WIDTH_MAX		2752
55 #define		MT9P031_WINDOW_WIDTH_DEF		2592
56 #define MT9P031_HORIZONTAL_BLANK			0x05
57 #define		MT9P031_HORIZONTAL_BLANK_MIN		0
58 #define		MT9P031_HORIZONTAL_BLANK_MAX		4095
59 #define MT9P031_VERTICAL_BLANK				0x06
60 #define		MT9P031_VERTICAL_BLANK_MIN		1
61 #define		MT9P031_VERTICAL_BLANK_MAX		4096
62 #define		MT9P031_VERTICAL_BLANK_DEF		26
63 #define MT9P031_OUTPUT_CONTROL				0x07
64 #define		MT9P031_OUTPUT_CONTROL_CEN		2
65 #define		MT9P031_OUTPUT_CONTROL_SYN		1
66 #define		MT9P031_OUTPUT_CONTROL_DEF		0x1f82
67 #define MT9P031_SHUTTER_WIDTH_UPPER			0x08
68 #define MT9P031_SHUTTER_WIDTH_LOWER			0x09
69 #define		MT9P031_SHUTTER_WIDTH_MIN		1
70 #define		MT9P031_SHUTTER_WIDTH_MAX		1048575
71 #define		MT9P031_SHUTTER_WIDTH_DEF		1943
72 #define	MT9P031_PLL_CONTROL				0x10
73 #define		MT9P031_PLL_CONTROL_PWROFF		0x0050
74 #define		MT9P031_PLL_CONTROL_PWRON		0x0051
75 #define		MT9P031_PLL_CONTROL_USEPLL		0x0052
76 #define	MT9P031_PLL_CONFIG_1				0x11
77 #define	MT9P031_PLL_CONFIG_2				0x12
78 #define MT9P031_PIXEL_CLOCK_CONTROL			0x0a
79 #define		MT9P031_PIXEL_CLOCK_INVERT		BIT(15)
80 #define		MT9P031_PIXEL_CLOCK_SHIFT(n)		((n) << 8)
81 #define		MT9P031_PIXEL_CLOCK_DIVIDE(n)		((n) << 0)
82 #define MT9P031_RESTART					0x0b
83 #define		MT9P031_FRAME_PAUSE_RESTART		BIT(1)
84 #define		MT9P031_FRAME_RESTART			BIT(0)
85 #define MT9P031_SHUTTER_DELAY				0x0c
86 #define MT9P031_RST					0x0d
87 #define		MT9P031_RST_ENABLE			BIT(0)
88 #define MT9P031_READ_MODE_1				0x1e
89 #define MT9P031_READ_MODE_2				0x20
90 #define		MT9P031_READ_MODE_2_ROW_MIR		BIT(15)
91 #define		MT9P031_READ_MODE_2_COL_MIR		BIT(14)
92 #define		MT9P031_READ_MODE_2_ROW_BLC		BIT(6)
93 #define MT9P031_ROW_ADDRESS_MODE			0x22
94 #define MT9P031_COLUMN_ADDRESS_MODE			0x23
95 #define MT9P031_GLOBAL_GAIN				0x35
96 #define		MT9P031_GLOBAL_GAIN_MIN			8
97 #define		MT9P031_GLOBAL_GAIN_MAX			1024
98 #define		MT9P031_GLOBAL_GAIN_DEF			8
99 #define		MT9P031_GLOBAL_GAIN_MULT		BIT(6)
100 #define MT9P031_ROW_BLACK_TARGET			0x49
101 #define MT9P031_ROW_BLACK_DEF_OFFSET			0x4b
102 #define MT9P031_GREEN1_OFFSET				0x60
103 #define MT9P031_GREEN2_OFFSET				0x61
104 #define MT9P031_BLACK_LEVEL_CALIBRATION			0x62
105 #define		MT9P031_BLC_MANUAL_BLC			BIT(0)
106 #define MT9P031_RED_OFFSET				0x63
107 #define MT9P031_BLUE_OFFSET				0x64
108 #define MT9P031_TEST_PATTERN				0xa0
109 #define		MT9P031_TEST_PATTERN_SHIFT		3
110 #define		MT9P031_TEST_PATTERN_ENABLE		BIT(0)
111 #define MT9P031_TEST_PATTERN_GREEN			0xa1
112 #define MT9P031_TEST_PATTERN_RED			0xa2
113 #define MT9P031_TEST_PATTERN_BLUE			0xa3
114 
115 enum mt9p031_model {
116 	MT9P031_MODEL_COLOR,
117 	MT9P031_MODEL_MONOCHROME,
118 };
119 
120 struct mt9p031 {
121 	struct v4l2_subdev subdev;
122 	struct media_pad pad;
123 	struct v4l2_rect crop;  /* Sensor window */
124 	struct v4l2_mbus_framefmt format;
125 	struct mt9p031_platform_data *pdata;
126 	struct mutex power_lock; /* lock to protect power_count */
127 	int power_count;
128 
129 	struct clk *clk;
130 	struct regulator_bulk_data regulators[3];
131 
132 	enum mt9p031_model model;
133 	struct aptina_pll pll;
134 	unsigned int clk_div;
135 	bool use_pll;
136 	struct gpio_desc *reset;
137 
138 	struct v4l2_ctrl_handler ctrls;
139 	struct v4l2_ctrl *blc_auto;
140 	struct v4l2_ctrl *blc_offset;
141 
142 	/* Registers cache */
143 	u16 output_control;
144 	u16 mode2;
145 };
146 
147 static struct mt9p031 *to_mt9p031(struct v4l2_subdev *sd)
148 {
149 	return container_of(sd, struct mt9p031, subdev);
150 }
151 
152 static int mt9p031_read(struct i2c_client *client, u8 reg)
153 {
154 	return i2c_smbus_read_word_swapped(client, reg);
155 }
156 
157 static int mt9p031_write(struct i2c_client *client, u8 reg, u16 data)
158 {
159 	return i2c_smbus_write_word_swapped(client, reg, data);
160 }
161 
162 static int mt9p031_set_output_control(struct mt9p031 *mt9p031, u16 clear,
163 				      u16 set)
164 {
165 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
166 	u16 value = (mt9p031->output_control & ~clear) | set;
167 	int ret;
168 
169 	ret = mt9p031_write(client, MT9P031_OUTPUT_CONTROL, value);
170 	if (ret < 0)
171 		return ret;
172 
173 	mt9p031->output_control = value;
174 	return 0;
175 }
176 
177 static int mt9p031_set_mode2(struct mt9p031 *mt9p031, u16 clear, u16 set)
178 {
179 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
180 	u16 value = (mt9p031->mode2 & ~clear) | set;
181 	int ret;
182 
183 	ret = mt9p031_write(client, MT9P031_READ_MODE_2, value);
184 	if (ret < 0)
185 		return ret;
186 
187 	mt9p031->mode2 = value;
188 	return 0;
189 }
190 
191 static int mt9p031_reset(struct mt9p031 *mt9p031)
192 {
193 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
194 	int ret;
195 
196 	/* Disable chip output, synchronous option update */
197 	ret = mt9p031_write(client, MT9P031_RST, MT9P031_RST_ENABLE);
198 	if (ret < 0)
199 		return ret;
200 	ret = mt9p031_write(client, MT9P031_RST, 0);
201 	if (ret < 0)
202 		return ret;
203 
204 	ret = mt9p031_write(client, MT9P031_PIXEL_CLOCK_CONTROL,
205 			    MT9P031_PIXEL_CLOCK_DIVIDE(mt9p031->clk_div));
206 	if (ret < 0)
207 		return ret;
208 
209 	return mt9p031_set_output_control(mt9p031, MT9P031_OUTPUT_CONTROL_CEN,
210 					  0);
211 }
212 
213 static int mt9p031_clk_setup(struct mt9p031 *mt9p031)
214 {
215 	static const struct aptina_pll_limits limits = {
216 		.ext_clock_min = 6000000,
217 		.ext_clock_max = 27000000,
218 		.int_clock_min = 2000000,
219 		.int_clock_max = 13500000,
220 		.out_clock_min = 180000000,
221 		.out_clock_max = 360000000,
222 		.pix_clock_max = 96000000,
223 		.n_min = 1,
224 		.n_max = 64,
225 		.m_min = 16,
226 		.m_max = 255,
227 		.p1_min = 1,
228 		.p1_max = 128,
229 	};
230 
231 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
232 	struct mt9p031_platform_data *pdata = mt9p031->pdata;
233 	unsigned long ext_freq;
234 	int ret;
235 
236 	mt9p031->clk = devm_clk_get(&client->dev, NULL);
237 	if (IS_ERR(mt9p031->clk))
238 		return PTR_ERR(mt9p031->clk);
239 
240 	ret = clk_set_rate(mt9p031->clk, pdata->ext_freq);
241 	if (ret < 0)
242 		return ret;
243 
244 	ext_freq = clk_get_rate(mt9p031->clk);
245 
246 	/* If the external clock frequency is out of bounds for the PLL use the
247 	 * pixel clock divider only and disable the PLL.
248 	 */
249 	if (ext_freq > limits.ext_clock_max) {
250 		unsigned int div;
251 
252 		div = DIV_ROUND_UP(ext_freq, pdata->target_freq);
253 		div = roundup_pow_of_two(div) / 2;
254 
255 		mt9p031->clk_div = min_t(unsigned int, div, 64);
256 		mt9p031->use_pll = false;
257 
258 		return 0;
259 	}
260 
261 	mt9p031->pll.ext_clock = ext_freq;
262 	mt9p031->pll.pix_clock = pdata->target_freq;
263 	mt9p031->use_pll = true;
264 
265 	return aptina_pll_calculate(&client->dev, &limits, &mt9p031->pll);
266 }
267 
268 static int mt9p031_pll_enable(struct mt9p031 *mt9p031)
269 {
270 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
271 	int ret;
272 
273 	if (!mt9p031->use_pll)
274 		return 0;
275 
276 	ret = mt9p031_write(client, MT9P031_PLL_CONTROL,
277 			    MT9P031_PLL_CONTROL_PWRON);
278 	if (ret < 0)
279 		return ret;
280 
281 	ret = mt9p031_write(client, MT9P031_PLL_CONFIG_1,
282 			    (mt9p031->pll.m << 8) | (mt9p031->pll.n - 1));
283 	if (ret < 0)
284 		return ret;
285 
286 	ret = mt9p031_write(client, MT9P031_PLL_CONFIG_2, mt9p031->pll.p1 - 1);
287 	if (ret < 0)
288 		return ret;
289 
290 	usleep_range(1000, 2000);
291 	ret = mt9p031_write(client, MT9P031_PLL_CONTROL,
292 			    MT9P031_PLL_CONTROL_PWRON |
293 			    MT9P031_PLL_CONTROL_USEPLL);
294 	return ret;
295 }
296 
297 static inline int mt9p031_pll_disable(struct mt9p031 *mt9p031)
298 {
299 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
300 
301 	if (!mt9p031->use_pll)
302 		return 0;
303 
304 	return mt9p031_write(client, MT9P031_PLL_CONTROL,
305 			     MT9P031_PLL_CONTROL_PWROFF);
306 }
307 
308 static int mt9p031_power_on(struct mt9p031 *mt9p031)
309 {
310 	int ret;
311 
312 	/* Ensure RESET_BAR is active */
313 	if (mt9p031->reset) {
314 		gpiod_set_value(mt9p031->reset, 1);
315 		usleep_range(1000, 2000);
316 	}
317 
318 	/* Bring up the supplies */
319 	ret = regulator_bulk_enable(ARRAY_SIZE(mt9p031->regulators),
320 				   mt9p031->regulators);
321 	if (ret < 0)
322 		return ret;
323 
324 	/* Enable clock */
325 	if (mt9p031->clk) {
326 		ret = clk_prepare_enable(mt9p031->clk);
327 		if (ret) {
328 			regulator_bulk_disable(ARRAY_SIZE(mt9p031->regulators),
329 					       mt9p031->regulators);
330 			return ret;
331 		}
332 	}
333 
334 	/* Now RESET_BAR must be high */
335 	if (mt9p031->reset) {
336 		gpiod_set_value(mt9p031->reset, 0);
337 		usleep_range(1000, 2000);
338 	}
339 
340 	return 0;
341 }
342 
343 static void mt9p031_power_off(struct mt9p031 *mt9p031)
344 {
345 	if (mt9p031->reset) {
346 		gpiod_set_value(mt9p031->reset, 1);
347 		usleep_range(1000, 2000);
348 	}
349 
350 	regulator_bulk_disable(ARRAY_SIZE(mt9p031->regulators),
351 			       mt9p031->regulators);
352 
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 	/* Configure the pixel clock polarity */
377 	if (mt9p031->pdata && mt9p031->pdata->pixclk_pol) {
378 		ret = mt9p031_write(client, MT9P031_PIXEL_CLOCK_CONTROL,
379 				MT9P031_PIXEL_CLOCK_INVERT);
380 		if (ret < 0)
381 			return ret;
382 	}
383 
384 	return v4l2_ctrl_handler_setup(&mt9p031->ctrls);
385 }
386 
387 /* -----------------------------------------------------------------------------
388  * V4L2 subdev video operations
389  */
390 
391 static int mt9p031_set_params(struct mt9p031 *mt9p031)
392 {
393 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
394 	struct v4l2_mbus_framefmt *format = &mt9p031->format;
395 	const struct v4l2_rect *crop = &mt9p031->crop;
396 	unsigned int hblank;
397 	unsigned int vblank;
398 	unsigned int xskip;
399 	unsigned int yskip;
400 	unsigned int xbin;
401 	unsigned int ybin;
402 	int ret;
403 
404 	/* Windows position and size.
405 	 *
406 	 * TODO: Make sure the start coordinates and window size match the
407 	 * skipping, binning and mirroring (see description of registers 2 and 4
408 	 * in table 13, and Binning section on page 41).
409 	 */
410 	ret = mt9p031_write(client, MT9P031_COLUMN_START, crop->left);
411 	if (ret < 0)
412 		return ret;
413 	ret = mt9p031_write(client, MT9P031_ROW_START, crop->top);
414 	if (ret < 0)
415 		return ret;
416 	ret = mt9p031_write(client, MT9P031_WINDOW_WIDTH, crop->width - 1);
417 	if (ret < 0)
418 		return ret;
419 	ret = mt9p031_write(client, MT9P031_WINDOW_HEIGHT, crop->height - 1);
420 	if (ret < 0)
421 		return ret;
422 
423 	/* Row and column binning and skipping. Use the maximum binning value
424 	 * compatible with the skipping settings.
425 	 */
426 	xskip = DIV_ROUND_CLOSEST(crop->width, format->width);
427 	yskip = DIV_ROUND_CLOSEST(crop->height, format->height);
428 	xbin = 1 << (ffs(xskip) - 1);
429 	ybin = 1 << (ffs(yskip) - 1);
430 
431 	ret = mt9p031_write(client, MT9P031_COLUMN_ADDRESS_MODE,
432 			    ((xbin - 1) << 4) | (xskip - 1));
433 	if (ret < 0)
434 		return ret;
435 	ret = mt9p031_write(client, MT9P031_ROW_ADDRESS_MODE,
436 			    ((ybin - 1) << 4) | (yskip - 1));
437 	if (ret < 0)
438 		return ret;
439 
440 	/* Blanking - use minimum value for horizontal blanking and default
441 	 * value for vertical blanking.
442 	 */
443 	hblank = 346 * ybin + 64 + (80 >> min_t(unsigned int, xbin, 3));
444 	vblank = MT9P031_VERTICAL_BLANK_DEF;
445 
446 	ret = mt9p031_write(client, MT9P031_HORIZONTAL_BLANK, hblank - 1);
447 	if (ret < 0)
448 		return ret;
449 	ret = mt9p031_write(client, MT9P031_VERTICAL_BLANK, vblank - 1);
450 	if (ret < 0)
451 		return ret;
452 
453 	return ret;
454 }
455 
456 static int mt9p031_s_stream(struct v4l2_subdev *subdev, int enable)
457 {
458 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
459 	struct i2c_client *client = v4l2_get_subdevdata(subdev);
460 	int val;
461 	int ret;
462 
463 	if (!enable) {
464 		/* enable pause restart */
465 		val = MT9P031_FRAME_PAUSE_RESTART;
466 		ret = mt9p031_write(client, MT9P031_RESTART, val);
467 		if (ret < 0)
468 			return ret;
469 
470 		/* enable restart + keep pause restart set */
471 		val |= MT9P031_FRAME_RESTART;
472 		ret = mt9p031_write(client, MT9P031_RESTART, val);
473 		if (ret < 0)
474 			return ret;
475 
476 		/* Stop sensor readout */
477 		ret = mt9p031_set_output_control(mt9p031,
478 						 MT9P031_OUTPUT_CONTROL_CEN, 0);
479 		if (ret < 0)
480 			return ret;
481 
482 		return mt9p031_pll_disable(mt9p031);
483 	}
484 
485 	ret = mt9p031_set_params(mt9p031);
486 	if (ret < 0)
487 		return ret;
488 
489 	/* Switch to master "normal" mode */
490 	ret = mt9p031_set_output_control(mt9p031, 0,
491 					 MT9P031_OUTPUT_CONTROL_CEN);
492 	if (ret < 0)
493 		return ret;
494 
495 	/*
496 	 * - clear pause restart
497 	 * - don't clear restart as clearing restart manually can cause
498 	 *   undefined behavior
499 	 */
500 	val = MT9P031_FRAME_RESTART;
501 	ret = mt9p031_write(client, MT9P031_RESTART, val);
502 	if (ret < 0)
503 		return ret;
504 
505 	return mt9p031_pll_enable(mt9p031);
506 }
507 
508 static int mt9p031_enum_mbus_code(struct v4l2_subdev *subdev,
509 				  struct v4l2_subdev_state *sd_state,
510 				  struct v4l2_subdev_mbus_code_enum *code)
511 {
512 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
513 
514 	if (code->pad || code->index)
515 		return -EINVAL;
516 
517 	code->code = mt9p031->format.code;
518 	return 0;
519 }
520 
521 static int mt9p031_enum_frame_size(struct v4l2_subdev *subdev,
522 				   struct v4l2_subdev_state *sd_state,
523 				   struct v4l2_subdev_frame_size_enum *fse)
524 {
525 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
526 
527 	if (fse->index >= 8 || fse->code != mt9p031->format.code)
528 		return -EINVAL;
529 
530 	fse->min_width = MT9P031_WINDOW_WIDTH_DEF
531 		       / min_t(unsigned int, 7, fse->index + 1);
532 	fse->max_width = fse->min_width;
533 	fse->min_height = MT9P031_WINDOW_HEIGHT_DEF / (fse->index + 1);
534 	fse->max_height = fse->min_height;
535 
536 	return 0;
537 }
538 
539 static struct v4l2_mbus_framefmt *
540 __mt9p031_get_pad_format(struct mt9p031 *mt9p031,
541 			 struct v4l2_subdev_state *sd_state,
542 			 unsigned int pad, u32 which)
543 {
544 	switch (which) {
545 	case V4L2_SUBDEV_FORMAT_TRY:
546 		return v4l2_subdev_get_try_format(&mt9p031->subdev, sd_state,
547 						  pad);
548 	case V4L2_SUBDEV_FORMAT_ACTIVE:
549 		return &mt9p031->format;
550 	default:
551 		return NULL;
552 	}
553 }
554 
555 static struct v4l2_rect *
556 __mt9p031_get_pad_crop(struct mt9p031 *mt9p031,
557 		       struct v4l2_subdev_state *sd_state,
558 		       unsigned int pad, u32 which)
559 {
560 	switch (which) {
561 	case V4L2_SUBDEV_FORMAT_TRY:
562 		return v4l2_subdev_get_try_crop(&mt9p031->subdev, sd_state,
563 						pad);
564 	case V4L2_SUBDEV_FORMAT_ACTIVE:
565 		return &mt9p031->crop;
566 	default:
567 		return NULL;
568 	}
569 }
570 
571 static int mt9p031_get_format(struct v4l2_subdev *subdev,
572 			      struct v4l2_subdev_state *sd_state,
573 			      struct v4l2_subdev_format *fmt)
574 {
575 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
576 
577 	fmt->format = *__mt9p031_get_pad_format(mt9p031, sd_state, fmt->pad,
578 						fmt->which);
579 	return 0;
580 }
581 
582 static int mt9p031_set_format(struct v4l2_subdev *subdev,
583 			      struct v4l2_subdev_state *sd_state,
584 			      struct v4l2_subdev_format *format)
585 {
586 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
587 	struct v4l2_mbus_framefmt *__format;
588 	struct v4l2_rect *__crop;
589 	unsigned int width;
590 	unsigned int height;
591 	unsigned int hratio;
592 	unsigned int vratio;
593 
594 	__crop = __mt9p031_get_pad_crop(mt9p031, sd_state, format->pad,
595 					format->which);
596 
597 	/* Clamp the width and height to avoid dividing by zero. */
598 	width = clamp_t(unsigned int, ALIGN(format->format.width, 2),
599 			max_t(unsigned int, __crop->width / 7,
600 			      MT9P031_WINDOW_WIDTH_MIN),
601 			__crop->width);
602 	height = clamp_t(unsigned int, ALIGN(format->format.height, 2),
603 			 max_t(unsigned int, __crop->height / 8,
604 			       MT9P031_WINDOW_HEIGHT_MIN),
605 			 __crop->height);
606 
607 	hratio = DIV_ROUND_CLOSEST(__crop->width, width);
608 	vratio = DIV_ROUND_CLOSEST(__crop->height, height);
609 
610 	__format = __mt9p031_get_pad_format(mt9p031, sd_state, format->pad,
611 					    format->which);
612 	__format->width = __crop->width / hratio;
613 	__format->height = __crop->height / vratio;
614 
615 	format->format = *__format;
616 
617 	return 0;
618 }
619 
620 static int mt9p031_get_selection(struct v4l2_subdev *subdev,
621 				 struct v4l2_subdev_state *sd_state,
622 				 struct v4l2_subdev_selection *sel)
623 {
624 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
625 
626 	if (sel->target != V4L2_SEL_TGT_CROP)
627 		return -EINVAL;
628 
629 	sel->r = *__mt9p031_get_pad_crop(mt9p031, sd_state, sel->pad,
630 					 sel->which);
631 	return 0;
632 }
633 
634 static int mt9p031_set_selection(struct v4l2_subdev *subdev,
635 				 struct v4l2_subdev_state *sd_state,
636 				 struct v4l2_subdev_selection *sel)
637 {
638 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
639 	struct v4l2_mbus_framefmt *__format;
640 	struct v4l2_rect *__crop;
641 	struct v4l2_rect rect;
642 
643 	if (sel->target != V4L2_SEL_TGT_CROP)
644 		return -EINVAL;
645 
646 	/* Clamp the crop rectangle boundaries and align them to a multiple of 2
647 	 * pixels to ensure a GRBG Bayer pattern.
648 	 */
649 	rect.left = clamp(ALIGN(sel->r.left, 2), MT9P031_COLUMN_START_MIN,
650 			  MT9P031_COLUMN_START_MAX);
651 	rect.top = clamp(ALIGN(sel->r.top, 2), MT9P031_ROW_START_MIN,
652 			 MT9P031_ROW_START_MAX);
653 	rect.width = clamp_t(unsigned int, ALIGN(sel->r.width, 2),
654 			     MT9P031_WINDOW_WIDTH_MIN,
655 			     MT9P031_WINDOW_WIDTH_MAX);
656 	rect.height = clamp_t(unsigned int, ALIGN(sel->r.height, 2),
657 			      MT9P031_WINDOW_HEIGHT_MIN,
658 			      MT9P031_WINDOW_HEIGHT_MAX);
659 
660 	rect.width = min_t(unsigned int, rect.width,
661 			   MT9P031_PIXEL_ARRAY_WIDTH - rect.left);
662 	rect.height = min_t(unsigned int, rect.height,
663 			    MT9P031_PIXEL_ARRAY_HEIGHT - rect.top);
664 
665 	__crop = __mt9p031_get_pad_crop(mt9p031, sd_state, sel->pad,
666 					sel->which);
667 
668 	if (rect.width != __crop->width || rect.height != __crop->height) {
669 		/* Reset the output image size if the crop rectangle size has
670 		 * been modified.
671 		 */
672 		__format = __mt9p031_get_pad_format(mt9p031, sd_state,
673 						    sel->pad,
674 						    sel->which);
675 		__format->width = rect.width;
676 		__format->height = rect.height;
677 	}
678 
679 	*__crop = rect;
680 	sel->r = rect;
681 
682 	return 0;
683 }
684 
685 /* -----------------------------------------------------------------------------
686  * V4L2 subdev control operations
687  */
688 
689 #define V4L2_CID_BLC_AUTO		(V4L2_CID_USER_BASE | 0x1002)
690 #define V4L2_CID_BLC_TARGET_LEVEL	(V4L2_CID_USER_BASE | 0x1003)
691 #define V4L2_CID_BLC_ANALOG_OFFSET	(V4L2_CID_USER_BASE | 0x1004)
692 #define V4L2_CID_BLC_DIGITAL_OFFSET	(V4L2_CID_USER_BASE | 0x1005)
693 
694 static int mt9p031_restore_blc(struct mt9p031 *mt9p031)
695 {
696 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
697 	int ret;
698 
699 	if (mt9p031->blc_auto->cur.val != 0) {
700 		ret = mt9p031_set_mode2(mt9p031, 0,
701 					MT9P031_READ_MODE_2_ROW_BLC);
702 		if (ret < 0)
703 			return ret;
704 	}
705 
706 	if (mt9p031->blc_offset->cur.val != 0) {
707 		ret = mt9p031_write(client, MT9P031_ROW_BLACK_TARGET,
708 				    mt9p031->blc_offset->cur.val);
709 		if (ret < 0)
710 			return ret;
711 	}
712 
713 	return 0;
714 }
715 
716 static int mt9p031_s_ctrl(struct v4l2_ctrl *ctrl)
717 {
718 	struct mt9p031 *mt9p031 =
719 			container_of(ctrl->handler, struct mt9p031, ctrls);
720 	struct i2c_client *client = v4l2_get_subdevdata(&mt9p031->subdev);
721 	u16 data;
722 	int ret;
723 
724 	if (ctrl->flags & V4L2_CTRL_FLAG_INACTIVE)
725 		return 0;
726 
727 	switch (ctrl->id) {
728 	case V4L2_CID_EXPOSURE:
729 		ret = mt9p031_write(client, MT9P031_SHUTTER_WIDTH_UPPER,
730 				    (ctrl->val >> 16) & 0xffff);
731 		if (ret < 0)
732 			return ret;
733 
734 		return mt9p031_write(client, MT9P031_SHUTTER_WIDTH_LOWER,
735 				     ctrl->val & 0xffff);
736 
737 	case V4L2_CID_GAIN:
738 		/* Gain is controlled by 2 analog stages and a digital stage.
739 		 * Valid values for the 3 stages are
740 		 *
741 		 * Stage                Min     Max     Step
742 		 * ------------------------------------------
743 		 * First analog stage   x1      x2      1
744 		 * Second analog stage  x1      x4      0.125
745 		 * Digital stage        x1      x16     0.125
746 		 *
747 		 * To minimize noise, the gain stages should be used in the
748 		 * second analog stage, first analog stage, digital stage order.
749 		 * Gain from a previous stage should be pushed to its maximum
750 		 * value before the next stage is used.
751 		 */
752 		if (ctrl->val <= 32) {
753 			data = ctrl->val;
754 		} else if (ctrl->val <= 64) {
755 			ctrl->val &= ~1;
756 			data = (1 << 6) | (ctrl->val >> 1);
757 		} else {
758 			ctrl->val &= ~7;
759 			data = ((ctrl->val - 64) << 5) | (1 << 6) | 32;
760 		}
761 
762 		return mt9p031_write(client, MT9P031_GLOBAL_GAIN, data);
763 
764 	case V4L2_CID_HFLIP:
765 		if (ctrl->val)
766 			return mt9p031_set_mode2(mt9p031,
767 					0, MT9P031_READ_MODE_2_COL_MIR);
768 		else
769 			return mt9p031_set_mode2(mt9p031,
770 					MT9P031_READ_MODE_2_COL_MIR, 0);
771 
772 	case V4L2_CID_VFLIP:
773 		if (ctrl->val)
774 			return mt9p031_set_mode2(mt9p031,
775 					0, MT9P031_READ_MODE_2_ROW_MIR);
776 		else
777 			return mt9p031_set_mode2(mt9p031,
778 					MT9P031_READ_MODE_2_ROW_MIR, 0);
779 
780 	case V4L2_CID_TEST_PATTERN:
781 		/* The digital side of the Black Level Calibration function must
782 		 * be disabled when generating a test pattern to avoid artifacts
783 		 * in the image. Activate (deactivate) the BLC-related controls
784 		 * when the test pattern is enabled (disabled).
785 		 */
786 		v4l2_ctrl_activate(mt9p031->blc_auto, ctrl->val == 0);
787 		v4l2_ctrl_activate(mt9p031->blc_offset, ctrl->val == 0);
788 
789 		if (!ctrl->val) {
790 			/* Restore the BLC settings. */
791 			ret = mt9p031_restore_blc(mt9p031);
792 			if (ret < 0)
793 				return ret;
794 
795 			return mt9p031_write(client, MT9P031_TEST_PATTERN, 0);
796 		}
797 
798 		ret = mt9p031_write(client, MT9P031_TEST_PATTERN_GREEN, 0x05a0);
799 		if (ret < 0)
800 			return ret;
801 		ret = mt9p031_write(client, MT9P031_TEST_PATTERN_RED, 0x0a50);
802 		if (ret < 0)
803 			return ret;
804 		ret = mt9p031_write(client, MT9P031_TEST_PATTERN_BLUE, 0x0aa0);
805 		if (ret < 0)
806 			return ret;
807 
808 		/* Disable digital BLC when generating a test pattern. */
809 		ret = mt9p031_set_mode2(mt9p031, MT9P031_READ_MODE_2_ROW_BLC,
810 					0);
811 		if (ret < 0)
812 			return ret;
813 
814 		ret = mt9p031_write(client, MT9P031_ROW_BLACK_DEF_OFFSET, 0);
815 		if (ret < 0)
816 			return ret;
817 
818 		return mt9p031_write(client, MT9P031_TEST_PATTERN,
819 				((ctrl->val - 1) << MT9P031_TEST_PATTERN_SHIFT)
820 				| MT9P031_TEST_PATTERN_ENABLE);
821 
822 	case V4L2_CID_BLC_AUTO:
823 		ret = mt9p031_set_mode2(mt9p031,
824 				ctrl->val ? 0 : MT9P031_READ_MODE_2_ROW_BLC,
825 				ctrl->val ? MT9P031_READ_MODE_2_ROW_BLC : 0);
826 		if (ret < 0)
827 			return ret;
828 
829 		return mt9p031_write(client, MT9P031_BLACK_LEVEL_CALIBRATION,
830 				     ctrl->val ? 0 : MT9P031_BLC_MANUAL_BLC);
831 
832 	case V4L2_CID_BLC_TARGET_LEVEL:
833 		return mt9p031_write(client, MT9P031_ROW_BLACK_TARGET,
834 				     ctrl->val);
835 
836 	case V4L2_CID_BLC_ANALOG_OFFSET:
837 		data = ctrl->val & ((1 << 9) - 1);
838 
839 		ret = mt9p031_write(client, MT9P031_GREEN1_OFFSET, data);
840 		if (ret < 0)
841 			return ret;
842 		ret = mt9p031_write(client, MT9P031_GREEN2_OFFSET, data);
843 		if (ret < 0)
844 			return ret;
845 		ret = mt9p031_write(client, MT9P031_RED_OFFSET, data);
846 		if (ret < 0)
847 			return ret;
848 		return mt9p031_write(client, MT9P031_BLUE_OFFSET, data);
849 
850 	case V4L2_CID_BLC_DIGITAL_OFFSET:
851 		return mt9p031_write(client, MT9P031_ROW_BLACK_DEF_OFFSET,
852 				     ctrl->val & ((1 << 12) - 1));
853 	}
854 
855 	return 0;
856 }
857 
858 static const struct v4l2_ctrl_ops mt9p031_ctrl_ops = {
859 	.s_ctrl = mt9p031_s_ctrl,
860 };
861 
862 static const char * const mt9p031_test_pattern_menu[] = {
863 	"Disabled",
864 	"Color Field",
865 	"Horizontal Gradient",
866 	"Vertical Gradient",
867 	"Diagonal Gradient",
868 	"Classic Test Pattern",
869 	"Walking 1s",
870 	"Monochrome Horizontal Bars",
871 	"Monochrome Vertical Bars",
872 	"Vertical Color Bars",
873 };
874 
875 static const struct v4l2_ctrl_config mt9p031_ctrls[] = {
876 	{
877 		.ops		= &mt9p031_ctrl_ops,
878 		.id		= V4L2_CID_BLC_AUTO,
879 		.type		= V4L2_CTRL_TYPE_BOOLEAN,
880 		.name		= "BLC, Auto",
881 		.min		= 0,
882 		.max		= 1,
883 		.step		= 1,
884 		.def		= 1,
885 		.flags		= 0,
886 	}, {
887 		.ops		= &mt9p031_ctrl_ops,
888 		.id		= V4L2_CID_BLC_TARGET_LEVEL,
889 		.type		= V4L2_CTRL_TYPE_INTEGER,
890 		.name		= "BLC Target Level",
891 		.min		= 0,
892 		.max		= 4095,
893 		.step		= 1,
894 		.def		= 168,
895 		.flags		= 0,
896 	}, {
897 		.ops		= &mt9p031_ctrl_ops,
898 		.id		= V4L2_CID_BLC_ANALOG_OFFSET,
899 		.type		= V4L2_CTRL_TYPE_INTEGER,
900 		.name		= "BLC Analog Offset",
901 		.min		= -255,
902 		.max		= 255,
903 		.step		= 1,
904 		.def		= 32,
905 		.flags		= 0,
906 	}, {
907 		.ops		= &mt9p031_ctrl_ops,
908 		.id		= V4L2_CID_BLC_DIGITAL_OFFSET,
909 		.type		= V4L2_CTRL_TYPE_INTEGER,
910 		.name		= "BLC Digital Offset",
911 		.min		= -2048,
912 		.max		= 2047,
913 		.step		= 1,
914 		.def		= 40,
915 		.flags		= 0,
916 	}
917 };
918 
919 /* -----------------------------------------------------------------------------
920  * V4L2 subdev core operations
921  */
922 
923 static int mt9p031_set_power(struct v4l2_subdev *subdev, int on)
924 {
925 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
926 	int ret = 0;
927 
928 	mutex_lock(&mt9p031->power_lock);
929 
930 	/* If the power count is modified from 0 to != 0 or from != 0 to 0,
931 	 * update the power state.
932 	 */
933 	if (mt9p031->power_count == !on) {
934 		ret = __mt9p031_set_power(mt9p031, !!on);
935 		if (ret < 0)
936 			goto out;
937 	}
938 
939 	/* Update the power count. */
940 	mt9p031->power_count += on ? 1 : -1;
941 	WARN_ON(mt9p031->power_count < 0);
942 
943 out:
944 	mutex_unlock(&mt9p031->power_lock);
945 	return ret;
946 }
947 
948 /* -----------------------------------------------------------------------------
949  * V4L2 subdev internal operations
950  */
951 
952 static int mt9p031_registered(struct v4l2_subdev *subdev)
953 {
954 	struct i2c_client *client = v4l2_get_subdevdata(subdev);
955 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
956 	s32 data;
957 	int ret;
958 
959 	ret = mt9p031_power_on(mt9p031);
960 	if (ret < 0) {
961 		dev_err(&client->dev, "MT9P031 power up failed\n");
962 		return ret;
963 	}
964 
965 	/* Read out the chip version register */
966 	data = mt9p031_read(client, MT9P031_CHIP_VERSION);
967 	mt9p031_power_off(mt9p031);
968 
969 	if (data != MT9P031_CHIP_VERSION_VALUE) {
970 		dev_err(&client->dev, "MT9P031 not detected, wrong version "
971 			"0x%04x\n", data);
972 		return -ENODEV;
973 	}
974 
975 	dev_info(&client->dev, "MT9P031 detected at address 0x%02x\n",
976 		 client->addr);
977 
978 	return 0;
979 }
980 
981 static int mt9p031_open(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
982 {
983 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
984 	struct v4l2_mbus_framefmt *format;
985 	struct v4l2_rect *crop;
986 
987 	crop = v4l2_subdev_get_try_crop(subdev, fh->state, 0);
988 	crop->left = MT9P031_COLUMN_START_DEF;
989 	crop->top = MT9P031_ROW_START_DEF;
990 	crop->width = MT9P031_WINDOW_WIDTH_DEF;
991 	crop->height = MT9P031_WINDOW_HEIGHT_DEF;
992 
993 	format = v4l2_subdev_get_try_format(subdev, fh->state, 0);
994 
995 	if (mt9p031->model == MT9P031_MODEL_MONOCHROME)
996 		format->code = MEDIA_BUS_FMT_Y12_1X12;
997 	else
998 		format->code = MEDIA_BUS_FMT_SGRBG12_1X12;
999 
1000 	format->width = MT9P031_WINDOW_WIDTH_DEF;
1001 	format->height = MT9P031_WINDOW_HEIGHT_DEF;
1002 	format->field = V4L2_FIELD_NONE;
1003 	format->colorspace = V4L2_COLORSPACE_SRGB;
1004 
1005 	return mt9p031_set_power(subdev, 1);
1006 }
1007 
1008 static int mt9p031_close(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh)
1009 {
1010 	return mt9p031_set_power(subdev, 0);
1011 }
1012 
1013 static const struct v4l2_subdev_core_ops mt9p031_subdev_core_ops = {
1014 	.s_power        = mt9p031_set_power,
1015 };
1016 
1017 static const struct v4l2_subdev_video_ops mt9p031_subdev_video_ops = {
1018 	.s_stream       = mt9p031_s_stream,
1019 };
1020 
1021 static const struct v4l2_subdev_pad_ops mt9p031_subdev_pad_ops = {
1022 	.enum_mbus_code = mt9p031_enum_mbus_code,
1023 	.enum_frame_size = mt9p031_enum_frame_size,
1024 	.get_fmt = mt9p031_get_format,
1025 	.set_fmt = mt9p031_set_format,
1026 	.get_selection = mt9p031_get_selection,
1027 	.set_selection = mt9p031_set_selection,
1028 };
1029 
1030 static const struct v4l2_subdev_ops mt9p031_subdev_ops = {
1031 	.core   = &mt9p031_subdev_core_ops,
1032 	.video  = &mt9p031_subdev_video_ops,
1033 	.pad    = &mt9p031_subdev_pad_ops,
1034 };
1035 
1036 static const struct v4l2_subdev_internal_ops mt9p031_subdev_internal_ops = {
1037 	.registered = mt9p031_registered,
1038 	.open = mt9p031_open,
1039 	.close = mt9p031_close,
1040 };
1041 
1042 /* -----------------------------------------------------------------------------
1043  * Driver initialization and probing
1044  */
1045 
1046 static struct mt9p031_platform_data *
1047 mt9p031_get_pdata(struct i2c_client *client)
1048 {
1049 	struct mt9p031_platform_data *pdata = NULL;
1050 	struct device_node *np;
1051 	struct v4l2_fwnode_endpoint endpoint = {
1052 		.bus_type = V4L2_MBUS_PARALLEL
1053 	};
1054 
1055 	if (!IS_ENABLED(CONFIG_OF) || !client->dev.of_node)
1056 		return client->dev.platform_data;
1057 
1058 	np = of_graph_get_next_endpoint(client->dev.of_node, NULL);
1059 	if (!np)
1060 		return NULL;
1061 
1062 	if (v4l2_fwnode_endpoint_parse(of_fwnode_handle(np), &endpoint) < 0)
1063 		goto done;
1064 
1065 	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
1066 	if (!pdata)
1067 		goto done;
1068 
1069 	of_property_read_u32(np, "input-clock-frequency", &pdata->ext_freq);
1070 	of_property_read_u32(np, "pixel-clock-frequency", &pdata->target_freq);
1071 
1072 	pdata->pixclk_pol = !!(endpoint.bus.parallel.flags &
1073 			       V4L2_MBUS_PCLK_SAMPLE_RISING);
1074 
1075 done:
1076 	of_node_put(np);
1077 	return pdata;
1078 }
1079 
1080 static int mt9p031_probe(struct i2c_client *client,
1081 			 const struct i2c_device_id *did)
1082 {
1083 	struct mt9p031_platform_data *pdata = mt9p031_get_pdata(client);
1084 	struct i2c_adapter *adapter = client->adapter;
1085 	struct mt9p031 *mt9p031;
1086 	unsigned int i;
1087 	int ret;
1088 
1089 	if (pdata == NULL) {
1090 		dev_err(&client->dev, "No platform data\n");
1091 		return -EINVAL;
1092 	}
1093 
1094 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
1095 		dev_warn(&client->dev,
1096 			"I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
1097 		return -EIO;
1098 	}
1099 
1100 	mt9p031 = devm_kzalloc(&client->dev, sizeof(*mt9p031), GFP_KERNEL);
1101 	if (mt9p031 == NULL)
1102 		return -ENOMEM;
1103 
1104 	mt9p031->pdata = pdata;
1105 	mt9p031->output_control	= MT9P031_OUTPUT_CONTROL_DEF;
1106 	mt9p031->mode2 = MT9P031_READ_MODE_2_ROW_BLC;
1107 	mt9p031->model = did->driver_data;
1108 
1109 	mt9p031->regulators[0].supply = "vdd";
1110 	mt9p031->regulators[1].supply = "vdd_io";
1111 	mt9p031->regulators[2].supply = "vaa";
1112 
1113 	ret = devm_regulator_bulk_get(&client->dev, 3, mt9p031->regulators);
1114 	if (ret < 0) {
1115 		dev_err(&client->dev, "Unable to get regulators\n");
1116 		return ret;
1117 	}
1118 
1119 	mutex_init(&mt9p031->power_lock);
1120 
1121 	v4l2_ctrl_handler_init(&mt9p031->ctrls, ARRAY_SIZE(mt9p031_ctrls) + 6);
1122 
1123 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1124 			  V4L2_CID_EXPOSURE, MT9P031_SHUTTER_WIDTH_MIN,
1125 			  MT9P031_SHUTTER_WIDTH_MAX, 1,
1126 			  MT9P031_SHUTTER_WIDTH_DEF);
1127 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1128 			  V4L2_CID_GAIN, MT9P031_GLOBAL_GAIN_MIN,
1129 			  MT9P031_GLOBAL_GAIN_MAX, 1, MT9P031_GLOBAL_GAIN_DEF);
1130 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1131 			  V4L2_CID_HFLIP, 0, 1, 1, 0);
1132 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1133 			  V4L2_CID_VFLIP, 0, 1, 1, 0);
1134 	v4l2_ctrl_new_std(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1135 			  V4L2_CID_PIXEL_RATE, pdata->target_freq,
1136 			  pdata->target_freq, 1, pdata->target_freq);
1137 	v4l2_ctrl_new_std_menu_items(&mt9p031->ctrls, &mt9p031_ctrl_ops,
1138 			  V4L2_CID_TEST_PATTERN,
1139 			  ARRAY_SIZE(mt9p031_test_pattern_menu) - 1, 0,
1140 			  0, mt9p031_test_pattern_menu);
1141 
1142 	for (i = 0; i < ARRAY_SIZE(mt9p031_ctrls); ++i)
1143 		v4l2_ctrl_new_custom(&mt9p031->ctrls, &mt9p031_ctrls[i], NULL);
1144 
1145 	mt9p031->subdev.ctrl_handler = &mt9p031->ctrls;
1146 
1147 	if (mt9p031->ctrls.error) {
1148 		printk(KERN_INFO "%s: control initialization error %d\n",
1149 		       __func__, mt9p031->ctrls.error);
1150 		ret = mt9p031->ctrls.error;
1151 		goto done;
1152 	}
1153 
1154 	mt9p031->blc_auto = v4l2_ctrl_find(&mt9p031->ctrls, V4L2_CID_BLC_AUTO);
1155 	mt9p031->blc_offset = v4l2_ctrl_find(&mt9p031->ctrls,
1156 					     V4L2_CID_BLC_DIGITAL_OFFSET);
1157 
1158 	v4l2_i2c_subdev_init(&mt9p031->subdev, client, &mt9p031_subdev_ops);
1159 	mt9p031->subdev.internal_ops = &mt9p031_subdev_internal_ops;
1160 
1161 	mt9p031->subdev.entity.function = MEDIA_ENT_F_CAM_SENSOR;
1162 	mt9p031->pad.flags = MEDIA_PAD_FL_SOURCE;
1163 	ret = media_entity_pads_init(&mt9p031->subdev.entity, 1, &mt9p031->pad);
1164 	if (ret < 0)
1165 		goto done;
1166 
1167 	mt9p031->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
1168 
1169 	mt9p031->crop.width = MT9P031_WINDOW_WIDTH_DEF;
1170 	mt9p031->crop.height = MT9P031_WINDOW_HEIGHT_DEF;
1171 	mt9p031->crop.left = MT9P031_COLUMN_START_DEF;
1172 	mt9p031->crop.top = MT9P031_ROW_START_DEF;
1173 
1174 	if (mt9p031->model == MT9P031_MODEL_MONOCHROME)
1175 		mt9p031->format.code = MEDIA_BUS_FMT_Y12_1X12;
1176 	else
1177 		mt9p031->format.code = MEDIA_BUS_FMT_SGRBG12_1X12;
1178 
1179 	mt9p031->format.width = MT9P031_WINDOW_WIDTH_DEF;
1180 	mt9p031->format.height = MT9P031_WINDOW_HEIGHT_DEF;
1181 	mt9p031->format.field = V4L2_FIELD_NONE;
1182 	mt9p031->format.colorspace = V4L2_COLORSPACE_SRGB;
1183 
1184 	mt9p031->reset = devm_gpiod_get_optional(&client->dev, "reset",
1185 						 GPIOD_OUT_HIGH);
1186 
1187 	ret = mt9p031_clk_setup(mt9p031);
1188 	if (ret)
1189 		goto done;
1190 
1191 	ret = v4l2_async_register_subdev(&mt9p031->subdev);
1192 
1193 done:
1194 	if (ret < 0) {
1195 		v4l2_ctrl_handler_free(&mt9p031->ctrls);
1196 		media_entity_cleanup(&mt9p031->subdev.entity);
1197 		mutex_destroy(&mt9p031->power_lock);
1198 	}
1199 
1200 	return ret;
1201 }
1202 
1203 static int mt9p031_remove(struct i2c_client *client)
1204 {
1205 	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
1206 	struct mt9p031 *mt9p031 = to_mt9p031(subdev);
1207 
1208 	v4l2_ctrl_handler_free(&mt9p031->ctrls);
1209 	v4l2_async_unregister_subdev(subdev);
1210 	media_entity_cleanup(&subdev->entity);
1211 	mutex_destroy(&mt9p031->power_lock);
1212 
1213 	return 0;
1214 }
1215 
1216 static const struct i2c_device_id mt9p031_id[] = {
1217 	{ "mt9p006", MT9P031_MODEL_COLOR },
1218 	{ "mt9p031", MT9P031_MODEL_COLOR },
1219 	{ "mt9p031m", MT9P031_MODEL_MONOCHROME },
1220 	{ }
1221 };
1222 MODULE_DEVICE_TABLE(i2c, mt9p031_id);
1223 
1224 #if IS_ENABLED(CONFIG_OF)
1225 static const struct of_device_id mt9p031_of_match[] = {
1226 	{ .compatible = "aptina,mt9p006", },
1227 	{ .compatible = "aptina,mt9p031", },
1228 	{ .compatible = "aptina,mt9p031m", },
1229 	{ /* sentinel */ },
1230 };
1231 MODULE_DEVICE_TABLE(of, mt9p031_of_match);
1232 #endif
1233 
1234 static struct i2c_driver mt9p031_i2c_driver = {
1235 	.driver = {
1236 		.of_match_table = of_match_ptr(mt9p031_of_match),
1237 		.name = "mt9p031",
1238 	},
1239 	.probe          = mt9p031_probe,
1240 	.remove         = mt9p031_remove,
1241 	.id_table       = mt9p031_id,
1242 };
1243 
1244 module_i2c_driver(mt9p031_i2c_driver);
1245 
1246 MODULE_DESCRIPTION("Aptina MT9P031 Camera driver");
1247 MODULE_AUTHOR("Bastian Hecht <hechtb@gmail.com>");
1248 MODULE_LICENSE("GPL v2");
1249