xref: /openbmc/linux/drivers/media/i2c/imx274.c (revision 43ffe817)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * imx274.c - IMX274 CMOS Image Sensor driver
4  *
5  * Copyright (C) 2017, Leopard Imaging, Inc.
6  *
7  * Leon Luo <leonl@leopardimaging.com>
8  * Edwin Zou <edwinz@leopardimaging.com>
9  * Luca Ceresoli <luca@lucaceresoli.net>
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/gpio.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/i2c.h>
17 #include <linux/init.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/of_gpio.h>
21 #include <linux/regmap.h>
22 #include <linux/slab.h>
23 #include <linux/v4l2-mediabus.h>
24 #include <linux/videodev2.h>
25 
26 #include <media/v4l2-ctrls.h>
27 #include <media/v4l2-device.h>
28 #include <media/v4l2-subdev.h>
29 
30 /*
31  * See "SHR, SVR Setting" in datasheet
32  */
33 #define IMX274_DEFAULT_FRAME_LENGTH		(4550)
34 #define IMX274_MAX_FRAME_LENGTH			(0x000fffff)
35 
36 /*
37  * See "Frame Rate Adjustment" in datasheet
38  */
39 #define IMX274_PIXCLK_CONST1			(72000000)
40 #define IMX274_PIXCLK_CONST2			(1000000)
41 
42 /*
43  * The input gain is shifted by IMX274_GAIN_SHIFT to get
44  * decimal number. The real gain is
45  * (float)input_gain_value / (1 << IMX274_GAIN_SHIFT)
46  */
47 #define IMX274_GAIN_SHIFT			(8)
48 #define IMX274_GAIN_SHIFT_MASK			((1 << IMX274_GAIN_SHIFT) - 1)
49 
50 /*
51  * See "Analog Gain" and "Digital Gain" in datasheet
52  * min gain is 1X
53  * max gain is calculated based on IMX274_GAIN_REG_MAX
54  */
55 #define IMX274_GAIN_REG_MAX			(1957)
56 #define IMX274_MIN_GAIN				(0x01 << IMX274_GAIN_SHIFT)
57 #define IMX274_MAX_ANALOG_GAIN			((2048 << IMX274_GAIN_SHIFT)\
58 					/ (2048 - IMX274_GAIN_REG_MAX))
59 #define IMX274_MAX_DIGITAL_GAIN			(8)
60 #define IMX274_DEF_GAIN				(20 << IMX274_GAIN_SHIFT)
61 #define IMX274_GAIN_CONST			(2048) /* for gain formula */
62 
63 /*
64  * 1 line time in us = (HMAX / 72), minimal is 4 lines
65  */
66 #define IMX274_MIN_EXPOSURE_TIME		(4 * 260 / 72)
67 
68 #define IMX274_DEFAULT_BINNING			IMX274_BINNING_OFF
69 #define IMX274_MAX_WIDTH			(3840)
70 #define IMX274_MAX_HEIGHT			(2160)
71 #define IMX274_MAX_FRAME_RATE			(120)
72 #define IMX274_MIN_FRAME_RATE			(5)
73 #define IMX274_DEF_FRAME_RATE			(60)
74 
75 /*
76  * register SHR is limited to (SVR value + 1) x VMAX value - 4
77  */
78 #define IMX274_SHR_LIMIT_CONST			(4)
79 
80 /*
81  * Min and max sensor reset delay (microseconds)
82  */
83 #define IMX274_RESET_DELAY1			(2000)
84 #define IMX274_RESET_DELAY2			(2200)
85 
86 /*
87  * shift and mask constants
88  */
89 #define IMX274_SHIFT_8_BITS			(8)
90 #define IMX274_SHIFT_16_BITS			(16)
91 #define IMX274_MASK_LSB_2_BITS			(0x03)
92 #define IMX274_MASK_LSB_3_BITS			(0x07)
93 #define IMX274_MASK_LSB_4_BITS			(0x0f)
94 #define IMX274_MASK_LSB_8_BITS			(0x00ff)
95 
96 #define DRIVER_NAME "IMX274"
97 
98 /*
99  * IMX274 register definitions
100  */
101 #define IMX274_SHR_REG_MSB			0x300D /* SHR */
102 #define IMX274_SHR_REG_LSB			0x300C /* SHR */
103 #define IMX274_SVR_REG_MSB			0x300F /* SVR */
104 #define IMX274_SVR_REG_LSB			0x300E /* SVR */
105 #define IMX274_HTRIM_EN_REG			0x3037
106 #define IMX274_HTRIM_START_REG_LSB		0x3038
107 #define IMX274_HTRIM_START_REG_MSB		0x3039
108 #define IMX274_HTRIM_END_REG_LSB		0x303A
109 #define IMX274_HTRIM_END_REG_MSB		0x303B
110 #define IMX274_VWIDCUTEN_REG			0x30DD
111 #define IMX274_VWIDCUT_REG_LSB			0x30DE
112 #define IMX274_VWIDCUT_REG_MSB			0x30DF
113 #define IMX274_VWINPOS_REG_LSB			0x30E0
114 #define IMX274_VWINPOS_REG_MSB			0x30E1
115 #define IMX274_WRITE_VSIZE_REG_LSB		0x3130
116 #define IMX274_WRITE_VSIZE_REG_MSB		0x3131
117 #define IMX274_Y_OUT_SIZE_REG_LSB		0x3132
118 #define IMX274_Y_OUT_SIZE_REG_MSB		0x3133
119 #define IMX274_VMAX_REG_1			0x30FA /* VMAX, MSB */
120 #define IMX274_VMAX_REG_2			0x30F9 /* VMAX */
121 #define IMX274_VMAX_REG_3			0x30F8 /* VMAX, LSB */
122 #define IMX274_HMAX_REG_MSB			0x30F7 /* HMAX */
123 #define IMX274_HMAX_REG_LSB			0x30F6 /* HMAX */
124 #define IMX274_ANALOG_GAIN_ADDR_LSB		0x300A /* ANALOG GAIN LSB */
125 #define IMX274_ANALOG_GAIN_ADDR_MSB		0x300B /* ANALOG GAIN MSB */
126 #define IMX274_DIGITAL_GAIN_REG			0x3012 /* Digital Gain */
127 #define IMX274_VFLIP_REG			0x301A /* VERTICAL FLIP */
128 #define IMX274_TEST_PATTERN_REG			0x303D /* TEST PATTERN */
129 #define IMX274_STANDBY_REG			0x3000 /* STANDBY */
130 
131 #define IMX274_TABLE_WAIT_MS			0
132 #define IMX274_TABLE_END			1
133 
134 /*
135  * imx274 I2C operation related structure
136  */
137 struct reg_8 {
138 	u16 addr;
139 	u8 val;
140 };
141 
142 static const struct regmap_config imx274_regmap_config = {
143 	.reg_bits = 16,
144 	.val_bits = 8,
145 	.cache_type = REGCACHE_RBTREE,
146 };
147 
148 enum imx274_binning {
149 	IMX274_BINNING_OFF,
150 	IMX274_BINNING_2_1,
151 	IMX274_BINNING_3_1,
152 };
153 
154 /*
155  * Parameters for each imx274 readout mode.
156  *
157  * These are the values to configure the sensor in one of the
158  * implemented modes.
159  *
160  * @init_regs: registers to initialize the mode
161  * @bin_ratio: downscale factor (e.g. 3 for 3:1 binning)
162  * @min_frame_len: Minimum frame length for each mode (see "Frame Rate
163  *                 Adjustment (CSI-2)" in the datasheet)
164  * @min_SHR: Minimum SHR register value (see "Shutter Setting (CSI-2)" in the
165  *           datasheet)
166  * @max_fps: Maximum frames per second
167  * @nocpiop: Number of clocks per internal offset period (see "Integration Time
168  *           in Each Readout Drive Mode (CSI-2)" in the datasheet)
169  */
170 struct imx274_mode {
171 	const struct reg_8 *init_regs;
172 	unsigned int bin_ratio;
173 	int min_frame_len;
174 	int min_SHR;
175 	int max_fps;
176 	int nocpiop;
177 };
178 
179 /*
180  * imx274 test pattern related structure
181  */
182 enum {
183 	TEST_PATTERN_DISABLED = 0,
184 	TEST_PATTERN_ALL_000H,
185 	TEST_PATTERN_ALL_FFFH,
186 	TEST_PATTERN_ALL_555H,
187 	TEST_PATTERN_ALL_AAAH,
188 	TEST_PATTERN_VSP_5AH, /* VERTICAL STRIPE PATTERN 555H/AAAH */
189 	TEST_PATTERN_VSP_A5H, /* VERTICAL STRIPE PATTERN AAAH/555H */
190 	TEST_PATTERN_VSP_05H, /* VERTICAL STRIPE PATTERN 000H/555H */
191 	TEST_PATTERN_VSP_50H, /* VERTICAL STRIPE PATTERN 555H/000H */
192 	TEST_PATTERN_VSP_0FH, /* VERTICAL STRIPE PATTERN 000H/FFFH */
193 	TEST_PATTERN_VSP_F0H, /* VERTICAL STRIPE PATTERN FFFH/000H */
194 	TEST_PATTERN_H_COLOR_BARS,
195 	TEST_PATTERN_V_COLOR_BARS,
196 };
197 
198 static const char * const tp_qmenu[] = {
199 	"Disabled",
200 	"All 000h Pattern",
201 	"All FFFh Pattern",
202 	"All 555h Pattern",
203 	"All AAAh Pattern",
204 	"Vertical Stripe (555h / AAAh)",
205 	"Vertical Stripe (AAAh / 555h)",
206 	"Vertical Stripe (000h / 555h)",
207 	"Vertical Stripe (555h / 000h)",
208 	"Vertical Stripe (000h / FFFh)",
209 	"Vertical Stripe (FFFh / 000h)",
210 	"Vertical Color Bars",
211 	"Horizontal Color Bars",
212 };
213 
214 /*
215  * All-pixel scan mode (10-bit)
216  * imx274 mode1(refer to datasheet) register configuration with
217  * 3840x2160 resolution, raw10 data and mipi four lane output
218  */
219 static const struct reg_8 imx274_mode1_3840x2160_raw10[] = {
220 	{0x3004, 0x01},
221 	{0x3005, 0x01},
222 	{0x3006, 0x00},
223 	{0x3007, 0xa2},
224 
225 	{0x3018, 0xA2}, /* output XVS, HVS */
226 
227 	{0x306B, 0x05},
228 	{0x30E2, 0x01},
229 
230 	{0x30EE, 0x01},
231 	{0x3342, 0x0A},
232 	{0x3343, 0x00},
233 	{0x3344, 0x16},
234 	{0x3345, 0x00},
235 	{0x33A6, 0x01},
236 	{0x3528, 0x0E},
237 	{0x3554, 0x1F},
238 	{0x3555, 0x01},
239 	{0x3556, 0x01},
240 	{0x3557, 0x01},
241 	{0x3558, 0x01},
242 	{0x3559, 0x00},
243 	{0x355A, 0x00},
244 	{0x35BA, 0x0E},
245 	{0x366A, 0x1B},
246 	{0x366B, 0x1A},
247 	{0x366C, 0x19},
248 	{0x366D, 0x17},
249 	{0x3A41, 0x08},
250 
251 	{IMX274_TABLE_END, 0x00}
252 };
253 
254 /*
255  * Horizontal/vertical 2/2-line binning
256  * (Horizontal and vertical weightedbinning, 10-bit)
257  * imx274 mode3(refer to datasheet) register configuration with
258  * 1920x1080 resolution, raw10 data and mipi four lane output
259  */
260 static const struct reg_8 imx274_mode3_1920x1080_raw10[] = {
261 	{0x3004, 0x02},
262 	{0x3005, 0x21},
263 	{0x3006, 0x00},
264 	{0x3007, 0xb1},
265 
266 	{0x3018, 0xA2}, /* output XVS, HVS */
267 
268 	{0x306B, 0x05},
269 	{0x30E2, 0x02},
270 
271 	{0x30EE, 0x01},
272 	{0x3342, 0x0A},
273 	{0x3343, 0x00},
274 	{0x3344, 0x1A},
275 	{0x3345, 0x00},
276 	{0x33A6, 0x01},
277 	{0x3528, 0x0E},
278 	{0x3554, 0x00},
279 	{0x3555, 0x01},
280 	{0x3556, 0x01},
281 	{0x3557, 0x01},
282 	{0x3558, 0x01},
283 	{0x3559, 0x00},
284 	{0x355A, 0x00},
285 	{0x35BA, 0x0E},
286 	{0x366A, 0x1B},
287 	{0x366B, 0x1A},
288 	{0x366C, 0x19},
289 	{0x366D, 0x17},
290 	{0x3A41, 0x08},
291 
292 	{IMX274_TABLE_END, 0x00}
293 };
294 
295 /*
296  * Vertical 2/3 subsampling binning horizontal 3 binning
297  * imx274 mode5(refer to datasheet) register configuration with
298  * 1280x720 resolution, raw10 data and mipi four lane output
299  */
300 static const struct reg_8 imx274_mode5_1280x720_raw10[] = {
301 	{0x3004, 0x03},
302 	{0x3005, 0x31},
303 	{0x3006, 0x00},
304 	{0x3007, 0xa9},
305 
306 	{0x3018, 0xA2}, /* output XVS, HVS */
307 
308 	{0x306B, 0x05},
309 	{0x30E2, 0x03},
310 
311 	{0x30EE, 0x01},
312 	{0x3342, 0x0A},
313 	{0x3343, 0x00},
314 	{0x3344, 0x1B},
315 	{0x3345, 0x00},
316 	{0x33A6, 0x01},
317 	{0x3528, 0x0E},
318 	{0x3554, 0x00},
319 	{0x3555, 0x01},
320 	{0x3556, 0x01},
321 	{0x3557, 0x01},
322 	{0x3558, 0x01},
323 	{0x3559, 0x00},
324 	{0x355A, 0x00},
325 	{0x35BA, 0x0E},
326 	{0x366A, 0x1B},
327 	{0x366B, 0x19},
328 	{0x366C, 0x17},
329 	{0x366D, 0x17},
330 	{0x3A41, 0x04},
331 
332 	{IMX274_TABLE_END, 0x00}
333 };
334 
335 /*
336  * imx274 first step register configuration for
337  * starting stream
338  */
339 static const struct reg_8 imx274_start_1[] = {
340 	{IMX274_STANDBY_REG, 0x12},
341 
342 	/* PLRD: clock settings */
343 	{0x3120, 0xF0},
344 	{0x3121, 0x00},
345 	{0x3122, 0x02},
346 	{0x3129, 0x9C},
347 	{0x312A, 0x02},
348 	{0x312D, 0x02},
349 
350 	{0x310B, 0x00},
351 
352 	/* PLSTMG */
353 	{0x304C, 0x00}, /* PLSTMG01 */
354 	{0x304D, 0x03},
355 	{0x331C, 0x1A},
356 	{0x331D, 0x00},
357 	{0x3502, 0x02},
358 	{0x3529, 0x0E},
359 	{0x352A, 0x0E},
360 	{0x352B, 0x0E},
361 	{0x3538, 0x0E},
362 	{0x3539, 0x0E},
363 	{0x3553, 0x00},
364 	{0x357D, 0x05},
365 	{0x357F, 0x05},
366 	{0x3581, 0x04},
367 	{0x3583, 0x76},
368 	{0x3587, 0x01},
369 	{0x35BB, 0x0E},
370 	{0x35BC, 0x0E},
371 	{0x35BD, 0x0E},
372 	{0x35BE, 0x0E},
373 	{0x35BF, 0x0E},
374 	{0x366E, 0x00},
375 	{0x366F, 0x00},
376 	{0x3670, 0x00},
377 	{0x3671, 0x00},
378 
379 	/* PSMIPI */
380 	{0x3304, 0x32}, /* PSMIPI1 */
381 	{0x3305, 0x00},
382 	{0x3306, 0x32},
383 	{0x3307, 0x00},
384 	{0x3590, 0x32},
385 	{0x3591, 0x00},
386 	{0x3686, 0x32},
387 	{0x3687, 0x00},
388 
389 	{IMX274_TABLE_END, 0x00}
390 };
391 
392 /*
393  * imx274 second step register configuration for
394  * starting stream
395  */
396 static const struct reg_8 imx274_start_2[] = {
397 	{IMX274_STANDBY_REG, 0x00},
398 	{0x303E, 0x02}, /* SYS_MODE = 2 */
399 	{IMX274_TABLE_END, 0x00}
400 };
401 
402 /*
403  * imx274 third step register configuration for
404  * starting stream
405  */
406 static const struct reg_8 imx274_start_3[] = {
407 	{0x30F4, 0x00},
408 	{0x3018, 0xA2}, /* XHS VHS OUTPUT */
409 	{IMX274_TABLE_END, 0x00}
410 };
411 
412 /*
413  * imx274 register configuration for stopping stream
414  */
415 static const struct reg_8 imx274_stop[] = {
416 	{IMX274_STANDBY_REG, 0x01},
417 	{IMX274_TABLE_END, 0x00}
418 };
419 
420 /*
421  * imx274 disable test pattern register configuration
422  */
423 static const struct reg_8 imx274_tp_disabled[] = {
424 	{0x303C, 0x00},
425 	{0x377F, 0x00},
426 	{0x3781, 0x00},
427 	{0x370B, 0x00},
428 	{IMX274_TABLE_END, 0x00}
429 };
430 
431 /*
432  * imx274 test pattern register configuration
433  * reg 0x303D defines the test pattern modes
434  */
435 static const struct reg_8 imx274_tp_regs[] = {
436 	{0x303C, 0x11},
437 	{0x370E, 0x01},
438 	{0x377F, 0x01},
439 	{0x3781, 0x01},
440 	{0x370B, 0x11},
441 	{IMX274_TABLE_END, 0x00}
442 };
443 
444 /* nocpiop happens to be the same number for the implemented modes */
445 static const struct imx274_mode imx274_modes[] = {
446 	{
447 		/* mode 1, 4K */
448 		.bin_ratio = 1,
449 		.init_regs = imx274_mode1_3840x2160_raw10,
450 		.min_frame_len = 4550,
451 		.min_SHR = 12,
452 		.max_fps = 60,
453 		.nocpiop = 112,
454 	},
455 	{
456 		/* mode 3, 1080p */
457 		.bin_ratio = 2,
458 		.init_regs = imx274_mode3_1920x1080_raw10,
459 		.min_frame_len = 2310,
460 		.min_SHR = 8,
461 		.max_fps = 120,
462 		.nocpiop = 112,
463 	},
464 	{
465 		/* mode 5, 720p */
466 		.bin_ratio = 3,
467 		.init_regs = imx274_mode5_1280x720_raw10,
468 		.min_frame_len = 2310,
469 		.min_SHR = 8,
470 		.max_fps = 120,
471 		.nocpiop = 112,
472 	},
473 };
474 
475 /*
476  * struct imx274_ctrls - imx274 ctrl structure
477  * @handler: V4L2 ctrl handler structure
478  * @exposure: Pointer to expsure ctrl structure
479  * @gain: Pointer to gain ctrl structure
480  * @vflip: Pointer to vflip ctrl structure
481  * @test_pattern: Pointer to test pattern ctrl structure
482  */
483 struct imx274_ctrls {
484 	struct v4l2_ctrl_handler handler;
485 	struct v4l2_ctrl *exposure;
486 	struct v4l2_ctrl *gain;
487 	struct v4l2_ctrl *vflip;
488 	struct v4l2_ctrl *test_pattern;
489 };
490 
491 /*
492  * struct stim274 - imx274 device structure
493  * @sd: V4L2 subdevice structure
494  * @pad: Media pad structure
495  * @client: Pointer to I2C client
496  * @ctrls: imx274 control structure
497  * @crop: rect to be captured
498  * @compose: compose rect, i.e. output resolution
499  * @format: V4L2 media bus frame format structure
500  *          (width and height are in sync with the compose rect)
501  * @frame_rate: V4L2 frame rate structure
502  * @regmap: Pointer to regmap structure
503  * @reset_gpio: Pointer to reset gpio
504  * @lock: Mutex structure
505  * @mode: Parameters for the selected readout mode
506  */
507 struct stimx274 {
508 	struct v4l2_subdev sd;
509 	struct media_pad pad;
510 	struct i2c_client *client;
511 	struct imx274_ctrls ctrls;
512 	struct v4l2_rect crop;
513 	struct v4l2_mbus_framefmt format;
514 	struct v4l2_fract frame_interval;
515 	struct regmap *regmap;
516 	struct gpio_desc *reset_gpio;
517 	struct mutex lock; /* mutex lock for operations */
518 	const struct imx274_mode *mode;
519 };
520 
521 #define IMX274_ROUND(dim, step, flags)			\
522 	((flags) & V4L2_SEL_FLAG_GE			\
523 	 ? roundup((dim), (step))			\
524 	 : ((flags) & V4L2_SEL_FLAG_LE			\
525 	    ? rounddown((dim), (step))			\
526 	    : rounddown((dim) + (step) / 2, (step))))
527 
528 /*
529  * Function declaration
530  */
531 static int imx274_set_gain(struct stimx274 *priv, struct v4l2_ctrl *ctrl);
532 static int imx274_set_exposure(struct stimx274 *priv, int val);
533 static int imx274_set_vflip(struct stimx274 *priv, int val);
534 static int imx274_set_test_pattern(struct stimx274 *priv, int val);
535 static int imx274_set_frame_interval(struct stimx274 *priv,
536 				     struct v4l2_fract frame_interval);
537 
538 static inline void msleep_range(unsigned int delay_base)
539 {
540 	usleep_range(delay_base * 1000, delay_base * 1000 + 500);
541 }
542 
543 /*
544  * v4l2_ctrl and v4l2_subdev related operations
545  */
546 static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
547 {
548 	return &container_of(ctrl->handler,
549 			     struct stimx274, ctrls.handler)->sd;
550 }
551 
552 static inline struct stimx274 *to_imx274(struct v4l2_subdev *sd)
553 {
554 	return container_of(sd, struct stimx274, sd);
555 }
556 
557 /*
558  * Writing a register table
559  *
560  * @priv: Pointer to device
561  * @table: Table containing register values (with optional delays)
562  *
563  * This is used to write register table into sensor's reg map.
564  *
565  * Return: 0 on success, errors otherwise
566  */
567 static int imx274_write_table(struct stimx274 *priv, const struct reg_8 table[])
568 {
569 	struct regmap *regmap = priv->regmap;
570 	int err = 0;
571 	const struct reg_8 *next;
572 	u8 val;
573 
574 	int range_start = -1;
575 	int range_count = 0;
576 	u8 range_vals[16];
577 	int max_range_vals = ARRAY_SIZE(range_vals);
578 
579 	for (next = table;; next++) {
580 		if ((next->addr != range_start + range_count) ||
581 		    (next->addr == IMX274_TABLE_END) ||
582 		    (next->addr == IMX274_TABLE_WAIT_MS) ||
583 		    (range_count == max_range_vals)) {
584 			if (range_count == 1)
585 				err = regmap_write(regmap,
586 						   range_start, range_vals[0]);
587 			else if (range_count > 1)
588 				err = regmap_bulk_write(regmap, range_start,
589 							&range_vals[0],
590 							range_count);
591 			else
592 				err = 0;
593 
594 			if (err)
595 				return err;
596 
597 			range_start = -1;
598 			range_count = 0;
599 
600 			/* Handle special address values */
601 			if (next->addr == IMX274_TABLE_END)
602 				break;
603 
604 			if (next->addr == IMX274_TABLE_WAIT_MS) {
605 				msleep_range(next->val);
606 				continue;
607 			}
608 		}
609 
610 		val = next->val;
611 
612 		if (range_start == -1)
613 			range_start = next->addr;
614 
615 		range_vals[range_count++] = val;
616 	}
617 	return 0;
618 }
619 
620 static inline int imx274_write_reg(struct stimx274 *priv, u16 addr, u8 val)
621 {
622 	int err;
623 
624 	err = regmap_write(priv->regmap, addr, val);
625 	if (err)
626 		dev_err(&priv->client->dev,
627 			"%s : i2c write failed, %x = %x\n", __func__,
628 			addr, val);
629 	else
630 		dev_dbg(&priv->client->dev,
631 			"%s : addr 0x%x, val=0x%x\n", __func__,
632 			addr, val);
633 	return err;
634 }
635 
636 /**
637  * Read a multibyte register.
638  *
639  * Uses a bulk read where possible.
640  *
641  * @priv: Pointer to device structure
642  * @addr: Address of the LSB register.  Other registers must be
643  *        consecutive, least-to-most significant.
644  * @val: Pointer to store the register value (cpu endianness)
645  * @nbytes: Number of bytes to read (range: [1..3]).
646  *          Other bytes are zet to 0.
647  *
648  * Return: 0 on success, errors otherwise
649  */
650 static int imx274_read_mbreg(struct stimx274 *priv, u16 addr, u32 *val,
651 			     size_t nbytes)
652 {
653 	__le32 val_le = 0;
654 	int err;
655 
656 	err = regmap_bulk_read(priv->regmap, addr, &val_le, nbytes);
657 	if (err) {
658 		dev_err(&priv->client->dev,
659 			"%s : i2c bulk read failed, %x (%zu bytes)\n",
660 			__func__, addr, nbytes);
661 	} else {
662 		*val = le32_to_cpu(val_le);
663 		dev_dbg(&priv->client->dev,
664 			"%s : addr 0x%x, val=0x%x (%zu bytes)\n",
665 			__func__, addr, *val, nbytes);
666 	}
667 
668 	return err;
669 }
670 
671 /**
672  * Write a multibyte register.
673  *
674  * Uses a bulk write where possible.
675  *
676  * @priv: Pointer to device structure
677  * @addr: Address of the LSB register.  Other registers must be
678  *        consecutive, least-to-most significant.
679  * @val: Value to be written to the register (cpu endianness)
680  * @nbytes: Number of bytes to write (range: [1..3])
681  */
682 static int imx274_write_mbreg(struct stimx274 *priv, u16 addr, u32 val,
683 			      size_t nbytes)
684 {
685 	__le32 val_le = cpu_to_le32(val);
686 	int err;
687 
688 	err = regmap_bulk_write(priv->regmap, addr, &val_le, nbytes);
689 	if (err)
690 		dev_err(&priv->client->dev,
691 			"%s : i2c bulk write failed, %x = %x (%zu bytes)\n",
692 			__func__, addr, val, nbytes);
693 	else
694 		dev_dbg(&priv->client->dev,
695 			"%s : addr 0x%x, val=0x%x (%zu bytes)\n",
696 			__func__, addr, val, nbytes);
697 	return err;
698 }
699 
700 /*
701  * Set mode registers to start stream.
702  * @priv: Pointer to device structure
703  *
704  * Return: 0 on success, errors otherwise
705  */
706 static int imx274_mode_regs(struct stimx274 *priv)
707 {
708 	int err = 0;
709 
710 	err = imx274_write_table(priv, imx274_start_1);
711 	if (err)
712 		return err;
713 
714 	err = imx274_write_table(priv, priv->mode->init_regs);
715 
716 	return err;
717 }
718 
719 /*
720  * imx274_start_stream - Function for starting stream per mode index
721  * @priv: Pointer to device structure
722  *
723  * Return: 0 on success, errors otherwise
724  */
725 static int imx274_start_stream(struct stimx274 *priv)
726 {
727 	int err = 0;
728 
729 	/*
730 	 * Refer to "Standby Cancel Sequence when using CSI-2" in
731 	 * imx274 datasheet, it should wait 10ms or more here.
732 	 * give it 1 extra ms for margin
733 	 */
734 	msleep_range(11);
735 	err = imx274_write_table(priv, imx274_start_2);
736 	if (err)
737 		return err;
738 
739 	/*
740 	 * Refer to "Standby Cancel Sequence when using CSI-2" in
741 	 * imx274 datasheet, it should wait 7ms or more here.
742 	 * give it 1 extra ms for margin
743 	 */
744 	msleep_range(8);
745 	err = imx274_write_table(priv, imx274_start_3);
746 	if (err)
747 		return err;
748 
749 	return 0;
750 }
751 
752 /*
753  * imx274_reset - Function called to reset the sensor
754  * @priv: Pointer to device structure
755  * @rst: Input value for determining the sensor's end state after reset
756  *
757  * Set the senor in reset and then
758  * if rst = 0, keep it in reset;
759  * if rst = 1, bring it out of reset.
760  *
761  */
762 static void imx274_reset(struct stimx274 *priv, int rst)
763 {
764 	gpiod_set_value_cansleep(priv->reset_gpio, 0);
765 	usleep_range(IMX274_RESET_DELAY1, IMX274_RESET_DELAY2);
766 	gpiod_set_value_cansleep(priv->reset_gpio, !!rst);
767 	usleep_range(IMX274_RESET_DELAY1, IMX274_RESET_DELAY2);
768 }
769 
770 /**
771  * imx274_s_ctrl - This is used to set the imx274 V4L2 controls
772  * @ctrl: V4L2 control to be set
773  *
774  * This function is used to set the V4L2 controls for the imx274 sensor.
775  *
776  * Return: 0 on success, errors otherwise
777  */
778 static int imx274_s_ctrl(struct v4l2_ctrl *ctrl)
779 {
780 	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
781 	struct stimx274 *imx274 = to_imx274(sd);
782 	int ret = -EINVAL;
783 
784 	dev_dbg(&imx274->client->dev,
785 		"%s : s_ctrl: %s, value: %d\n", __func__,
786 		ctrl->name, ctrl->val);
787 
788 	switch (ctrl->id) {
789 	case V4L2_CID_EXPOSURE:
790 		dev_dbg(&imx274->client->dev,
791 			"%s : set V4L2_CID_EXPOSURE\n", __func__);
792 		ret = imx274_set_exposure(imx274, ctrl->val);
793 		break;
794 
795 	case V4L2_CID_GAIN:
796 		dev_dbg(&imx274->client->dev,
797 			"%s : set V4L2_CID_GAIN\n", __func__);
798 		ret = imx274_set_gain(imx274, ctrl);
799 		break;
800 
801 	case V4L2_CID_VFLIP:
802 		dev_dbg(&imx274->client->dev,
803 			"%s : set V4L2_CID_VFLIP\n", __func__);
804 		ret = imx274_set_vflip(imx274, ctrl->val);
805 		break;
806 
807 	case V4L2_CID_TEST_PATTERN:
808 		dev_dbg(&imx274->client->dev,
809 			"%s : set V4L2_CID_TEST_PATTERN\n", __func__);
810 		ret = imx274_set_test_pattern(imx274, ctrl->val);
811 		break;
812 	}
813 
814 	return ret;
815 }
816 
817 static int imx274_binning_goodness(struct stimx274 *imx274,
818 				   int w, int ask_w,
819 				   int h, int ask_h, u32 flags)
820 {
821 	struct device *dev = &imx274->client->dev;
822 	const int goodness = 100000;
823 	int val = 0;
824 
825 	if (flags & V4L2_SEL_FLAG_GE) {
826 		if (w < ask_w)
827 			val -= goodness;
828 		if (h < ask_h)
829 			val -= goodness;
830 	}
831 
832 	if (flags & V4L2_SEL_FLAG_LE) {
833 		if (w > ask_w)
834 			val -= goodness;
835 		if (h > ask_h)
836 			val -= goodness;
837 	}
838 
839 	val -= abs(w - ask_w);
840 	val -= abs(h - ask_h);
841 
842 	dev_dbg(dev, "%s: ask %dx%d, size %dx%d, goodness %d\n",
843 		__func__, ask_w, ask_h, w, h, val);
844 
845 	return val;
846 }
847 
848 /**
849  * Helper function to change binning and set both compose and format.
850  *
851  * We have two entry points to change binning: set_fmt and
852  * set_selection(COMPOSE). Both have to compute the new output size
853  * and set it in both the compose rect and the frame format size. We
854  * also need to do the same things after setting cropping to restore
855  * 1:1 binning.
856  *
857  * This function contains the common code for these three cases, it
858  * has many arguments in order to accommodate the needs of all of
859  * them.
860  *
861  * Must be called with imx274->lock locked.
862  *
863  * @imx274: The device object
864  * @cfg:    The pad config we are editing for TRY requests
865  * @which:  V4L2_SUBDEV_FORMAT_ACTIVE or V4L2_SUBDEV_FORMAT_TRY from the caller
866  * @width:  Input-output parameter: set to the desired width before
867  *          the call, contains the chosen value after returning successfully
868  * @height: Input-output parameter for height (see @width)
869  * @flags:  Selection flags from struct v4l2_subdev_selection, or 0 if not
870  *          available (when called from set_fmt)
871  */
872 static int __imx274_change_compose(struct stimx274 *imx274,
873 				   struct v4l2_subdev_pad_config *cfg,
874 				   u32 which,
875 				   u32 *width,
876 				   u32 *height,
877 				   u32 flags)
878 {
879 	struct device *dev = &imx274->client->dev;
880 	const struct v4l2_rect *cur_crop;
881 	struct v4l2_mbus_framefmt *tgt_fmt;
882 	unsigned int i;
883 	const struct imx274_mode *best_mode = &imx274_modes[0];
884 	int best_goodness = INT_MIN;
885 
886 	if (which == V4L2_SUBDEV_FORMAT_TRY) {
887 		cur_crop = &cfg->try_crop;
888 		tgt_fmt = &cfg->try_fmt;
889 	} else {
890 		cur_crop = &imx274->crop;
891 		tgt_fmt = &imx274->format;
892 	}
893 
894 	for (i = 0; i < ARRAY_SIZE(imx274_modes); i++) {
895 		unsigned int ratio = imx274_modes[i].bin_ratio;
896 
897 		int goodness = imx274_binning_goodness(
898 			imx274,
899 			cur_crop->width / ratio, *width,
900 			cur_crop->height / ratio, *height,
901 			flags);
902 
903 		if (goodness >= best_goodness) {
904 			best_goodness = goodness;
905 			best_mode = &imx274_modes[i];
906 		}
907 	}
908 
909 	*width = cur_crop->width / best_mode->bin_ratio;
910 	*height = cur_crop->height / best_mode->bin_ratio;
911 
912 	if (which == V4L2_SUBDEV_FORMAT_ACTIVE)
913 		imx274->mode = best_mode;
914 
915 	dev_dbg(dev, "%s: selected %u:1 binning\n",
916 		__func__, best_mode->bin_ratio);
917 
918 	tgt_fmt->width = *width;
919 	tgt_fmt->height = *height;
920 	tgt_fmt->field = V4L2_FIELD_NONE;
921 
922 	return 0;
923 }
924 
925 /**
926  * imx274_get_fmt - Get the pad format
927  * @sd: Pointer to V4L2 Sub device structure
928  * @cfg: Pointer to sub device pad information structure
929  * @fmt: Pointer to pad level media bus format
930  *
931  * This function is used to get the pad format information.
932  *
933  * Return: 0 on success
934  */
935 static int imx274_get_fmt(struct v4l2_subdev *sd,
936 			  struct v4l2_subdev_pad_config *cfg,
937 			  struct v4l2_subdev_format *fmt)
938 {
939 	struct stimx274 *imx274 = to_imx274(sd);
940 
941 	mutex_lock(&imx274->lock);
942 	fmt->format = imx274->format;
943 	mutex_unlock(&imx274->lock);
944 	return 0;
945 }
946 
947 /**
948  * imx274_set_fmt - This is used to set the pad format
949  * @sd: Pointer to V4L2 Sub device structure
950  * @cfg: Pointer to sub device pad information structure
951  * @format: Pointer to pad level media bus format
952  *
953  * This function is used to set the pad format.
954  *
955  * Return: 0 on success
956  */
957 static int imx274_set_fmt(struct v4l2_subdev *sd,
958 			  struct v4l2_subdev_pad_config *cfg,
959 			  struct v4l2_subdev_format *format)
960 {
961 	struct v4l2_mbus_framefmt *fmt = &format->format;
962 	struct stimx274 *imx274 = to_imx274(sd);
963 	int err = 0;
964 
965 	mutex_lock(&imx274->lock);
966 
967 	err = __imx274_change_compose(imx274, cfg, format->which,
968 				      &fmt->width, &fmt->height, 0);
969 
970 	if (err)
971 		goto out;
972 
973 	/*
974 	 * __imx274_change_compose already set width and height in the
975 	 * applicable format, but we need to keep all other format
976 	 * values, so do a full copy here
977 	 */
978 	fmt->field = V4L2_FIELD_NONE;
979 	if (format->which == V4L2_SUBDEV_FORMAT_TRY)
980 		cfg->try_fmt = *fmt;
981 	else
982 		imx274->format = *fmt;
983 
984 out:
985 	mutex_unlock(&imx274->lock);
986 
987 	return err;
988 }
989 
990 static int imx274_get_selection(struct v4l2_subdev *sd,
991 				struct v4l2_subdev_pad_config *cfg,
992 				struct v4l2_subdev_selection *sel)
993 {
994 	struct stimx274 *imx274 = to_imx274(sd);
995 	const struct v4l2_rect *src_crop;
996 	const struct v4l2_mbus_framefmt *src_fmt;
997 	int ret = 0;
998 
999 	if (sel->pad != 0)
1000 		return -EINVAL;
1001 
1002 	if (sel->target == V4L2_SEL_TGT_CROP_BOUNDS) {
1003 		sel->r.left = 0;
1004 		sel->r.top = 0;
1005 		sel->r.width = IMX274_MAX_WIDTH;
1006 		sel->r.height = IMX274_MAX_HEIGHT;
1007 		return 0;
1008 	}
1009 
1010 	if (sel->which == V4L2_SUBDEV_FORMAT_TRY) {
1011 		src_crop = &cfg->try_crop;
1012 		src_fmt = &cfg->try_fmt;
1013 	} else {
1014 		src_crop = &imx274->crop;
1015 		src_fmt = &imx274->format;
1016 	}
1017 
1018 	mutex_lock(&imx274->lock);
1019 
1020 	switch (sel->target) {
1021 	case V4L2_SEL_TGT_CROP:
1022 		sel->r = *src_crop;
1023 		break;
1024 	case V4L2_SEL_TGT_COMPOSE_BOUNDS:
1025 		sel->r.top = 0;
1026 		sel->r.left = 0;
1027 		sel->r.width = src_crop->width;
1028 		sel->r.height = src_crop->height;
1029 		break;
1030 	case V4L2_SEL_TGT_COMPOSE:
1031 		sel->r.top = 0;
1032 		sel->r.left = 0;
1033 		sel->r.width = src_fmt->width;
1034 		sel->r.height = src_fmt->height;
1035 		break;
1036 	default:
1037 		ret = -EINVAL;
1038 	}
1039 
1040 	mutex_unlock(&imx274->lock);
1041 
1042 	return ret;
1043 }
1044 
1045 static int imx274_set_selection_crop(struct stimx274 *imx274,
1046 				     struct v4l2_subdev_pad_config *cfg,
1047 				     struct v4l2_subdev_selection *sel)
1048 {
1049 	struct v4l2_rect *tgt_crop;
1050 	struct v4l2_rect new_crop;
1051 	bool size_changed;
1052 
1053 	/*
1054 	 * h_step could be 12 or 24 depending on the binning. But we
1055 	 * won't know the binning until we choose the mode later in
1056 	 * __imx274_change_compose(). Thus let's be safe and use the
1057 	 * most conservative value in all cases.
1058 	 */
1059 	const u32 h_step = 24;
1060 
1061 	new_crop.width = min_t(u32,
1062 			       IMX274_ROUND(sel->r.width, h_step, sel->flags),
1063 			       IMX274_MAX_WIDTH);
1064 
1065 	/* Constraint: HTRIMMING_END - HTRIMMING_START >= 144 */
1066 	if (new_crop.width < 144)
1067 		new_crop.width = 144;
1068 
1069 	new_crop.left = min_t(u32,
1070 			      IMX274_ROUND(sel->r.left, h_step, 0),
1071 			      IMX274_MAX_WIDTH - new_crop.width);
1072 
1073 	new_crop.height = min_t(u32,
1074 				IMX274_ROUND(sel->r.height, 2, sel->flags),
1075 				IMX274_MAX_HEIGHT);
1076 
1077 	new_crop.top = min_t(u32, IMX274_ROUND(sel->r.top, 2, 0),
1078 			     IMX274_MAX_HEIGHT - new_crop.height);
1079 
1080 	sel->r = new_crop;
1081 
1082 	if (sel->which == V4L2_SUBDEV_FORMAT_TRY)
1083 		tgt_crop = &cfg->try_crop;
1084 	else
1085 		tgt_crop = &imx274->crop;
1086 
1087 	mutex_lock(&imx274->lock);
1088 
1089 	size_changed = (new_crop.width != tgt_crop->width ||
1090 			new_crop.height != tgt_crop->height);
1091 
1092 	/* __imx274_change_compose needs the new size in *tgt_crop */
1093 	*tgt_crop = new_crop;
1094 
1095 	/* if crop size changed then reset the output image size */
1096 	if (size_changed)
1097 		__imx274_change_compose(imx274, cfg, sel->which,
1098 					&new_crop.width, &new_crop.height,
1099 					sel->flags);
1100 
1101 	mutex_unlock(&imx274->lock);
1102 
1103 	return 0;
1104 }
1105 
1106 static int imx274_set_selection(struct v4l2_subdev *sd,
1107 				struct v4l2_subdev_pad_config *cfg,
1108 				struct v4l2_subdev_selection *sel)
1109 {
1110 	struct stimx274 *imx274 = to_imx274(sd);
1111 
1112 	if (sel->pad != 0)
1113 		return -EINVAL;
1114 
1115 	if (sel->target == V4L2_SEL_TGT_CROP)
1116 		return imx274_set_selection_crop(imx274, cfg, sel);
1117 
1118 	if (sel->target == V4L2_SEL_TGT_COMPOSE) {
1119 		int err;
1120 
1121 		mutex_lock(&imx274->lock);
1122 		err =  __imx274_change_compose(imx274, cfg, sel->which,
1123 					       &sel->r.width, &sel->r.height,
1124 					       sel->flags);
1125 		mutex_unlock(&imx274->lock);
1126 
1127 		/*
1128 		 * __imx274_change_compose already set width and
1129 		 * height in set->r, we still need to set top-left
1130 		 */
1131 		if (!err) {
1132 			sel->r.top = 0;
1133 			sel->r.left = 0;
1134 		}
1135 
1136 		return err;
1137 	}
1138 
1139 	return -EINVAL;
1140 }
1141 
1142 static int imx274_apply_trimming(struct stimx274 *imx274)
1143 {
1144 	u32 h_start;
1145 	u32 h_end;
1146 	u32 hmax;
1147 	u32 v_cut;
1148 	s32 v_pos;
1149 	u32 write_v_size;
1150 	u32 y_out_size;
1151 	int err;
1152 
1153 	h_start = imx274->crop.left + 12;
1154 	h_end = h_start + imx274->crop.width;
1155 
1156 	/* Use the minimum allowed value of HMAX */
1157 	/* Note: except in mode 1, (width / 16 + 23) is always < hmax_min */
1158 	/* Note: 260 is the minimum HMAX in all implemented modes */
1159 	hmax = max_t(u32, 260, (imx274->crop.width) / 16 + 23);
1160 
1161 	/* invert v_pos if VFLIP */
1162 	v_pos = imx274->ctrls.vflip->cur.val ?
1163 		(-imx274->crop.top / 2) : (imx274->crop.top / 2);
1164 	v_cut = (IMX274_MAX_HEIGHT - imx274->crop.height) / 2;
1165 	write_v_size = imx274->crop.height + 22;
1166 	y_out_size   = imx274->crop.height + 14;
1167 
1168 	err = imx274_write_mbreg(imx274, IMX274_HMAX_REG_LSB, hmax, 2);
1169 	if (!err)
1170 		err = imx274_write_mbreg(imx274, IMX274_HTRIM_EN_REG, 1, 1);
1171 	if (!err)
1172 		err = imx274_write_mbreg(imx274, IMX274_HTRIM_START_REG_LSB,
1173 					 h_start, 2);
1174 	if (!err)
1175 		err = imx274_write_mbreg(imx274, IMX274_HTRIM_END_REG_LSB,
1176 					 h_end, 2);
1177 	if (!err)
1178 		err = imx274_write_mbreg(imx274, IMX274_VWIDCUTEN_REG, 1, 1);
1179 	if (!err)
1180 		err = imx274_write_mbreg(imx274, IMX274_VWIDCUT_REG_LSB,
1181 					 v_cut, 2);
1182 	if (!err)
1183 		err = imx274_write_mbreg(imx274, IMX274_VWINPOS_REG_LSB,
1184 					 v_pos, 2);
1185 	if (!err)
1186 		err = imx274_write_mbreg(imx274, IMX274_WRITE_VSIZE_REG_LSB,
1187 					 write_v_size, 2);
1188 	if (!err)
1189 		err = imx274_write_mbreg(imx274, IMX274_Y_OUT_SIZE_REG_LSB,
1190 					 y_out_size, 2);
1191 
1192 	return err;
1193 }
1194 
1195 /**
1196  * imx274_g_frame_interval - Get the frame interval
1197  * @sd: Pointer to V4L2 Sub device structure
1198  * @fi: Pointer to V4l2 Sub device frame interval structure
1199  *
1200  * This function is used to get the frame interval.
1201  *
1202  * Return: 0 on success
1203  */
1204 static int imx274_g_frame_interval(struct v4l2_subdev *sd,
1205 				   struct v4l2_subdev_frame_interval *fi)
1206 {
1207 	struct stimx274 *imx274 = to_imx274(sd);
1208 
1209 	fi->interval = imx274->frame_interval;
1210 	dev_dbg(&imx274->client->dev, "%s frame rate = %d / %d\n",
1211 		__func__, imx274->frame_interval.numerator,
1212 		imx274->frame_interval.denominator);
1213 
1214 	return 0;
1215 }
1216 
1217 /**
1218  * imx274_s_frame_interval - Set the frame interval
1219  * @sd: Pointer to V4L2 Sub device structure
1220  * @fi: Pointer to V4l2 Sub device frame interval structure
1221  *
1222  * This function is used to set the frame intervavl.
1223  *
1224  * Return: 0 on success
1225  */
1226 static int imx274_s_frame_interval(struct v4l2_subdev *sd,
1227 				   struct v4l2_subdev_frame_interval *fi)
1228 {
1229 	struct stimx274 *imx274 = to_imx274(sd);
1230 	struct v4l2_ctrl *ctrl = imx274->ctrls.exposure;
1231 	int min, max, def;
1232 	int ret;
1233 
1234 	mutex_lock(&imx274->lock);
1235 	ret = imx274_set_frame_interval(imx274, fi->interval);
1236 
1237 	if (!ret) {
1238 		fi->interval = imx274->frame_interval;
1239 
1240 		/*
1241 		 * exposure time range is decided by frame interval
1242 		 * need to update it after frame interval changes
1243 		 */
1244 		min = IMX274_MIN_EXPOSURE_TIME;
1245 		max = fi->interval.numerator * 1000000
1246 			/ fi->interval.denominator;
1247 		def = max;
1248 		if (__v4l2_ctrl_modify_range(ctrl, min, max, 1, def)) {
1249 			dev_err(&imx274->client->dev,
1250 				"Exposure ctrl range update failed\n");
1251 			goto unlock;
1252 		}
1253 
1254 		/* update exposure time accordingly */
1255 		imx274_set_exposure(imx274, ctrl->val);
1256 
1257 		dev_dbg(&imx274->client->dev, "set frame interval to %uus\n",
1258 			fi->interval.numerator * 1000000
1259 			/ fi->interval.denominator);
1260 	}
1261 
1262 unlock:
1263 	mutex_unlock(&imx274->lock);
1264 
1265 	return ret;
1266 }
1267 
1268 /**
1269  * imx274_load_default - load default control values
1270  * @priv: Pointer to device structure
1271  *
1272  * Return: 0 on success, errors otherwise
1273  */
1274 static int imx274_load_default(struct stimx274 *priv)
1275 {
1276 	int ret;
1277 
1278 	/* load default control values */
1279 	priv->frame_interval.numerator = 1;
1280 	priv->frame_interval.denominator = IMX274_DEF_FRAME_RATE;
1281 	priv->ctrls.exposure->val = 1000000 / IMX274_DEF_FRAME_RATE;
1282 	priv->ctrls.gain->val = IMX274_DEF_GAIN;
1283 	priv->ctrls.vflip->val = 0;
1284 	priv->ctrls.test_pattern->val = TEST_PATTERN_DISABLED;
1285 
1286 	/* update frame rate */
1287 	ret = imx274_set_frame_interval(priv,
1288 					priv->frame_interval);
1289 	if (ret)
1290 		return ret;
1291 
1292 	/* update exposure time */
1293 	ret = v4l2_ctrl_s_ctrl(priv->ctrls.exposure, priv->ctrls.exposure->val);
1294 	if (ret)
1295 		return ret;
1296 
1297 	/* update gain */
1298 	ret = v4l2_ctrl_s_ctrl(priv->ctrls.gain, priv->ctrls.gain->val);
1299 	if (ret)
1300 		return ret;
1301 
1302 	/* update vflip */
1303 	ret = v4l2_ctrl_s_ctrl(priv->ctrls.vflip, priv->ctrls.vflip->val);
1304 	if (ret)
1305 		return ret;
1306 
1307 	return 0;
1308 }
1309 
1310 /**
1311  * imx274_s_stream - It is used to start/stop the streaming.
1312  * @sd: V4L2 Sub device
1313  * @on: Flag (True / False)
1314  *
1315  * This function controls the start or stop of streaming for the
1316  * imx274 sensor.
1317  *
1318  * Return: 0 on success, errors otherwise
1319  */
1320 static int imx274_s_stream(struct v4l2_subdev *sd, int on)
1321 {
1322 	struct stimx274 *imx274 = to_imx274(sd);
1323 	int ret = 0;
1324 
1325 	dev_dbg(&imx274->client->dev, "%s : %s, mode index = %td\n", __func__,
1326 		on ? "Stream Start" : "Stream Stop",
1327 		imx274->mode - &imx274_modes[0]);
1328 
1329 	mutex_lock(&imx274->lock);
1330 
1331 	if (on) {
1332 		/* load mode registers */
1333 		ret = imx274_mode_regs(imx274);
1334 		if (ret)
1335 			goto fail;
1336 
1337 		ret = imx274_apply_trimming(imx274);
1338 		if (ret)
1339 			goto fail;
1340 
1341 		/*
1342 		 * update frame rate & expsoure. if the last mode is different,
1343 		 * HMAX could be changed. As the result, frame rate & exposure
1344 		 * are changed.
1345 		 * gain is not affected.
1346 		 */
1347 		ret = imx274_set_frame_interval(imx274,
1348 						imx274->frame_interval);
1349 		if (ret)
1350 			goto fail;
1351 
1352 		/* update exposure time */
1353 		ret = __v4l2_ctrl_s_ctrl(imx274->ctrls.exposure,
1354 					 imx274->ctrls.exposure->val);
1355 		if (ret)
1356 			goto fail;
1357 
1358 		/* start stream */
1359 		ret = imx274_start_stream(imx274);
1360 		if (ret)
1361 			goto fail;
1362 	} else {
1363 		/* stop stream */
1364 		ret = imx274_write_table(imx274, imx274_stop);
1365 		if (ret)
1366 			goto fail;
1367 	}
1368 
1369 	mutex_unlock(&imx274->lock);
1370 	dev_dbg(&imx274->client->dev, "%s : Done\n", __func__);
1371 	return 0;
1372 
1373 fail:
1374 	mutex_unlock(&imx274->lock);
1375 	dev_err(&imx274->client->dev, "s_stream failed\n");
1376 	return ret;
1377 }
1378 
1379 /*
1380  * imx274_get_frame_length - Function for obtaining current frame length
1381  * @priv: Pointer to device structure
1382  * @val: Pointer to obainted value
1383  *
1384  * frame_length = vmax x (svr + 1), in unit of hmax.
1385  *
1386  * Return: 0 on success
1387  */
1388 static int imx274_get_frame_length(struct stimx274 *priv, u32 *val)
1389 {
1390 	int err;
1391 	u32 svr;
1392 	u32 vmax;
1393 
1394 	err = imx274_read_mbreg(priv, IMX274_SVR_REG_LSB, &svr, 2);
1395 	if (err)
1396 		goto fail;
1397 
1398 	err = imx274_read_mbreg(priv, IMX274_VMAX_REG_3, &vmax, 3);
1399 	if (err)
1400 		goto fail;
1401 
1402 	*val = vmax * (svr + 1);
1403 
1404 	return 0;
1405 
1406 fail:
1407 	dev_err(&priv->client->dev, "%s error = %d\n", __func__, err);
1408 	return err;
1409 }
1410 
1411 static int imx274_clamp_coarse_time(struct stimx274 *priv, u32 *val,
1412 				    u32 *frame_length)
1413 {
1414 	int err;
1415 
1416 	err = imx274_get_frame_length(priv, frame_length);
1417 	if (err)
1418 		return err;
1419 
1420 	if (*frame_length < priv->mode->min_frame_len)
1421 		*frame_length =  priv->mode->min_frame_len;
1422 
1423 	*val = *frame_length - *val; /* convert to raw shr */
1424 	if (*val > *frame_length - IMX274_SHR_LIMIT_CONST)
1425 		*val = *frame_length - IMX274_SHR_LIMIT_CONST;
1426 	else if (*val < priv->mode->min_SHR)
1427 		*val = priv->mode->min_SHR;
1428 
1429 	return 0;
1430 }
1431 
1432 /*
1433  * imx274_set_digital gain - Function called when setting digital gain
1434  * @priv: Pointer to device structure
1435  * @dgain: Value of digital gain.
1436  *
1437  * Digital gain has only 4 steps: 1x, 2x, 4x, and 8x
1438  *
1439  * Return: 0 on success
1440  */
1441 static int imx274_set_digital_gain(struct stimx274 *priv, u32 dgain)
1442 {
1443 	u8 reg_val;
1444 
1445 	reg_val = ffs(dgain);
1446 
1447 	if (reg_val)
1448 		reg_val--;
1449 
1450 	reg_val = clamp(reg_val, (u8)0, (u8)3);
1451 
1452 	return imx274_write_reg(priv, IMX274_DIGITAL_GAIN_REG,
1453 				reg_val & IMX274_MASK_LSB_4_BITS);
1454 }
1455 
1456 /*
1457  * imx274_set_gain - Function called when setting gain
1458  * @priv: Pointer to device structure
1459  * @val: Value of gain. the real value = val << IMX274_GAIN_SHIFT;
1460  * @ctrl: v4l2 control pointer
1461  *
1462  * Set the gain based on input value.
1463  * The caller should hold the mutex lock imx274->lock if necessary
1464  *
1465  * Return: 0 on success
1466  */
1467 static int imx274_set_gain(struct stimx274 *priv, struct v4l2_ctrl *ctrl)
1468 {
1469 	int err;
1470 	u32 gain, analog_gain, digital_gain, gain_reg;
1471 
1472 	gain = (u32)(ctrl->val);
1473 
1474 	dev_dbg(&priv->client->dev,
1475 		"%s : input gain = %d.%d\n", __func__,
1476 		gain >> IMX274_GAIN_SHIFT,
1477 		((gain & IMX274_GAIN_SHIFT_MASK) * 100) >> IMX274_GAIN_SHIFT);
1478 
1479 	if (gain > IMX274_MAX_DIGITAL_GAIN * IMX274_MAX_ANALOG_GAIN)
1480 		gain = IMX274_MAX_DIGITAL_GAIN * IMX274_MAX_ANALOG_GAIN;
1481 	else if (gain < IMX274_MIN_GAIN)
1482 		gain = IMX274_MIN_GAIN;
1483 
1484 	if (gain <= IMX274_MAX_ANALOG_GAIN)
1485 		digital_gain = 1;
1486 	else if (gain <= IMX274_MAX_ANALOG_GAIN * 2)
1487 		digital_gain = 2;
1488 	else if (gain <= IMX274_MAX_ANALOG_GAIN * 4)
1489 		digital_gain = 4;
1490 	else
1491 		digital_gain = IMX274_MAX_DIGITAL_GAIN;
1492 
1493 	analog_gain = gain / digital_gain;
1494 
1495 	dev_dbg(&priv->client->dev,
1496 		"%s : digital gain = %d, analog gain = %d.%d\n",
1497 		__func__, digital_gain, analog_gain >> IMX274_GAIN_SHIFT,
1498 		((analog_gain & IMX274_GAIN_SHIFT_MASK) * 100)
1499 		>> IMX274_GAIN_SHIFT);
1500 
1501 	err = imx274_set_digital_gain(priv, digital_gain);
1502 	if (err)
1503 		goto fail;
1504 
1505 	/* convert to register value, refer to imx274 datasheet */
1506 	gain_reg = (u32)IMX274_GAIN_CONST -
1507 		(IMX274_GAIN_CONST << IMX274_GAIN_SHIFT) / analog_gain;
1508 	if (gain_reg > IMX274_GAIN_REG_MAX)
1509 		gain_reg = IMX274_GAIN_REG_MAX;
1510 
1511 	err = imx274_write_mbreg(priv, IMX274_ANALOG_GAIN_ADDR_LSB, gain_reg,
1512 				 2);
1513 	if (err)
1514 		goto fail;
1515 
1516 	if (IMX274_GAIN_CONST - gain_reg == 0) {
1517 		err = -EINVAL;
1518 		goto fail;
1519 	}
1520 
1521 	/* convert register value back to gain value */
1522 	ctrl->val = (IMX274_GAIN_CONST << IMX274_GAIN_SHIFT)
1523 			/ (IMX274_GAIN_CONST - gain_reg) * digital_gain;
1524 
1525 	dev_dbg(&priv->client->dev,
1526 		"%s : GAIN control success, gain_reg = %d, new gain = %d\n",
1527 		__func__, gain_reg, ctrl->val);
1528 
1529 	return 0;
1530 
1531 fail:
1532 	dev_err(&priv->client->dev, "%s error = %d\n", __func__, err);
1533 	return err;
1534 }
1535 
1536 /*
1537  * imx274_set_coarse_time - Function called when setting SHR value
1538  * @priv: Pointer to device structure
1539  * @val: Value for exposure time in number of line_length, or [HMAX]
1540  *
1541  * Set SHR value based on input value.
1542  *
1543  * Return: 0 on success
1544  */
1545 static int imx274_set_coarse_time(struct stimx274 *priv, u32 *val)
1546 {
1547 	int err;
1548 	u32 coarse_time, frame_length;
1549 
1550 	coarse_time = *val;
1551 
1552 	/* convert exposure_time to appropriate SHR value */
1553 	err = imx274_clamp_coarse_time(priv, &coarse_time, &frame_length);
1554 	if (err)
1555 		goto fail;
1556 
1557 	err = imx274_write_mbreg(priv, IMX274_SHR_REG_LSB, coarse_time, 2);
1558 	if (err)
1559 		goto fail;
1560 
1561 	*val = frame_length - coarse_time;
1562 	return 0;
1563 
1564 fail:
1565 	dev_err(&priv->client->dev, "%s error = %d\n", __func__, err);
1566 	return err;
1567 }
1568 
1569 /*
1570  * imx274_set_exposure - Function called when setting exposure time
1571  * @priv: Pointer to device structure
1572  * @val: Variable for exposure time, in the unit of micro-second
1573  *
1574  * Set exposure time based on input value.
1575  * The caller should hold the mutex lock imx274->lock if necessary
1576  *
1577  * Return: 0 on success
1578  */
1579 static int imx274_set_exposure(struct stimx274 *priv, int val)
1580 {
1581 	int err;
1582 	u32 hmax;
1583 	u32 coarse_time; /* exposure time in unit of line (HMAX)*/
1584 
1585 	dev_dbg(&priv->client->dev,
1586 		"%s : EXPOSURE control input = %d\n", __func__, val);
1587 
1588 	/* step 1: convert input exposure_time (val) into number of 1[HMAX] */
1589 
1590 	err = imx274_read_mbreg(priv, IMX274_HMAX_REG_LSB, &hmax, 2);
1591 	if (err)
1592 		goto fail;
1593 
1594 	if (hmax == 0) {
1595 		err = -EINVAL;
1596 		goto fail;
1597 	}
1598 
1599 	coarse_time = (IMX274_PIXCLK_CONST1 / IMX274_PIXCLK_CONST2 * val
1600 			- priv->mode->nocpiop) / hmax;
1601 
1602 	/* step 2: convert exposure_time into SHR value */
1603 
1604 	/* set SHR */
1605 	err = imx274_set_coarse_time(priv, &coarse_time);
1606 	if (err)
1607 		goto fail;
1608 
1609 	priv->ctrls.exposure->val =
1610 			(coarse_time * hmax + priv->mode->nocpiop)
1611 			/ (IMX274_PIXCLK_CONST1 / IMX274_PIXCLK_CONST2);
1612 
1613 	dev_dbg(&priv->client->dev,
1614 		"%s : EXPOSURE control success\n", __func__);
1615 	return 0;
1616 
1617 fail:
1618 	dev_err(&priv->client->dev, "%s error = %d\n", __func__, err);
1619 
1620 	return err;
1621 }
1622 
1623 /*
1624  * imx274_set_vflip - Function called when setting vertical flip
1625  * @priv: Pointer to device structure
1626  * @val: Value for vflip setting
1627  *
1628  * Set vertical flip based on input value.
1629  * val = 0: normal, no vertical flip
1630  * val = 1: vertical flip enabled
1631  * The caller should hold the mutex lock imx274->lock if necessary
1632  *
1633  * Return: 0 on success
1634  */
1635 static int imx274_set_vflip(struct stimx274 *priv, int val)
1636 {
1637 	int err;
1638 
1639 	err = imx274_write_reg(priv, IMX274_VFLIP_REG, val);
1640 	if (err) {
1641 		dev_err(&priv->client->dev, "VFLIP control error\n");
1642 		return err;
1643 	}
1644 
1645 	dev_dbg(&priv->client->dev,
1646 		"%s : VFLIP control success\n", __func__);
1647 
1648 	return 0;
1649 }
1650 
1651 /*
1652  * imx274_set_test_pattern - Function called when setting test pattern
1653  * @priv: Pointer to device structure
1654  * @val: Variable for test pattern
1655  *
1656  * Set to different test patterns based on input value.
1657  *
1658  * Return: 0 on success
1659  */
1660 static int imx274_set_test_pattern(struct stimx274 *priv, int val)
1661 {
1662 	int err = 0;
1663 
1664 	if (val == TEST_PATTERN_DISABLED) {
1665 		err = imx274_write_table(priv, imx274_tp_disabled);
1666 	} else if (val <= TEST_PATTERN_V_COLOR_BARS) {
1667 		err = imx274_write_reg(priv, IMX274_TEST_PATTERN_REG, val - 1);
1668 		if (!err)
1669 			err = imx274_write_table(priv, imx274_tp_regs);
1670 	} else {
1671 		err = -EINVAL;
1672 	}
1673 
1674 	if (!err)
1675 		dev_dbg(&priv->client->dev,
1676 			"%s : TEST PATTERN control success\n", __func__);
1677 	else
1678 		dev_err(&priv->client->dev, "%s error = %d\n", __func__, err);
1679 
1680 	return err;
1681 }
1682 
1683 /*
1684  * imx274_set_frame_length - Function called when setting frame length
1685  * @priv: Pointer to device structure
1686  * @val: Variable for frame length (= VMAX, i.e. vertical drive period length)
1687  *
1688  * Set frame length based on input value.
1689  *
1690  * Return: 0 on success
1691  */
1692 static int imx274_set_frame_length(struct stimx274 *priv, u32 val)
1693 {
1694 	int err;
1695 	u32 frame_length;
1696 
1697 	dev_dbg(&priv->client->dev, "%s : input length = %d\n",
1698 		__func__, val);
1699 
1700 	frame_length = (u32)val;
1701 
1702 	err = imx274_write_mbreg(priv, IMX274_VMAX_REG_3, frame_length, 3);
1703 	if (err)
1704 		goto fail;
1705 
1706 	return 0;
1707 
1708 fail:
1709 	dev_err(&priv->client->dev, "%s error = %d\n", __func__, err);
1710 	return err;
1711 }
1712 
1713 /*
1714  * imx274_set_frame_interval - Function called when setting frame interval
1715  * @priv: Pointer to device structure
1716  * @frame_interval: Variable for frame interval
1717  *
1718  * Change frame interval by updating VMAX value
1719  * The caller should hold the mutex lock imx274->lock if necessary
1720  *
1721  * Return: 0 on success
1722  */
1723 static int imx274_set_frame_interval(struct stimx274 *priv,
1724 				     struct v4l2_fract frame_interval)
1725 {
1726 	int err;
1727 	u32 frame_length, req_frame_rate;
1728 	u32 svr;
1729 	u32 hmax;
1730 
1731 	dev_dbg(&priv->client->dev, "%s: input frame interval = %d / %d",
1732 		__func__, frame_interval.numerator,
1733 		frame_interval.denominator);
1734 
1735 	if (frame_interval.numerator == 0 || frame_interval.denominator == 0) {
1736 		frame_interval.denominator = IMX274_DEF_FRAME_RATE;
1737 		frame_interval.numerator = 1;
1738 	}
1739 
1740 	req_frame_rate = (u32)(frame_interval.denominator
1741 				/ frame_interval.numerator);
1742 
1743 	/* boundary check */
1744 	if (req_frame_rate > priv->mode->max_fps) {
1745 		frame_interval.numerator = 1;
1746 		frame_interval.denominator = priv->mode->max_fps;
1747 	} else if (req_frame_rate < IMX274_MIN_FRAME_RATE) {
1748 		frame_interval.numerator = 1;
1749 		frame_interval.denominator = IMX274_MIN_FRAME_RATE;
1750 	}
1751 
1752 	/*
1753 	 * VMAX = 1/frame_rate x 72M / (SVR+1) / HMAX
1754 	 * frame_length (i.e. VMAX) = (frame_interval) x 72M /(SVR+1) / HMAX
1755 	 */
1756 
1757 	err = imx274_read_mbreg(priv, IMX274_SVR_REG_LSB, &svr, 2);
1758 	if (err)
1759 		goto fail;
1760 
1761 	dev_dbg(&priv->client->dev,
1762 		"%s : register SVR = %d\n", __func__, svr);
1763 
1764 	err = imx274_read_mbreg(priv, IMX274_HMAX_REG_LSB, &hmax, 2);
1765 	if (err)
1766 		goto fail;
1767 
1768 	dev_dbg(&priv->client->dev,
1769 		"%s : register HMAX = %d\n", __func__, hmax);
1770 
1771 	if (hmax == 0 || frame_interval.denominator == 0) {
1772 		err = -EINVAL;
1773 		goto fail;
1774 	}
1775 
1776 	frame_length = IMX274_PIXCLK_CONST1 / (svr + 1) / hmax
1777 					* frame_interval.numerator
1778 					/ frame_interval.denominator;
1779 
1780 	err = imx274_set_frame_length(priv, frame_length);
1781 	if (err)
1782 		goto fail;
1783 
1784 	priv->frame_interval = frame_interval;
1785 	return 0;
1786 
1787 fail:
1788 	dev_err(&priv->client->dev, "%s error = %d\n", __func__, err);
1789 	return err;
1790 }
1791 
1792 static const struct v4l2_subdev_pad_ops imx274_pad_ops = {
1793 	.get_fmt = imx274_get_fmt,
1794 	.set_fmt = imx274_set_fmt,
1795 	.get_selection = imx274_get_selection,
1796 	.set_selection = imx274_set_selection,
1797 };
1798 
1799 static const struct v4l2_subdev_video_ops imx274_video_ops = {
1800 	.g_frame_interval = imx274_g_frame_interval,
1801 	.s_frame_interval = imx274_s_frame_interval,
1802 	.s_stream = imx274_s_stream,
1803 };
1804 
1805 static const struct v4l2_subdev_ops imx274_subdev_ops = {
1806 	.pad = &imx274_pad_ops,
1807 	.video = &imx274_video_ops,
1808 };
1809 
1810 static const struct v4l2_ctrl_ops imx274_ctrl_ops = {
1811 	.s_ctrl	= imx274_s_ctrl,
1812 };
1813 
1814 static const struct of_device_id imx274_of_id_table[] = {
1815 	{ .compatible = "sony,imx274" },
1816 	{ }
1817 };
1818 MODULE_DEVICE_TABLE(of, imx274_of_id_table);
1819 
1820 static const struct i2c_device_id imx274_id[] = {
1821 	{ "IMX274", 0 },
1822 	{ }
1823 };
1824 MODULE_DEVICE_TABLE(i2c, imx274_id);
1825 
1826 static int imx274_probe(struct i2c_client *client)
1827 {
1828 	struct v4l2_subdev *sd;
1829 	struct stimx274 *imx274;
1830 	int ret;
1831 
1832 	/* initialize imx274 */
1833 	imx274 = devm_kzalloc(&client->dev, sizeof(*imx274), GFP_KERNEL);
1834 	if (!imx274)
1835 		return -ENOMEM;
1836 
1837 	mutex_init(&imx274->lock);
1838 
1839 	/* initialize format */
1840 	imx274->mode = &imx274_modes[IMX274_DEFAULT_BINNING];
1841 	imx274->crop.width = IMX274_MAX_WIDTH;
1842 	imx274->crop.height = IMX274_MAX_HEIGHT;
1843 	imx274->format.width = imx274->crop.width / imx274->mode->bin_ratio;
1844 	imx274->format.height = imx274->crop.height / imx274->mode->bin_ratio;
1845 	imx274->format.field = V4L2_FIELD_NONE;
1846 	imx274->format.code = MEDIA_BUS_FMT_SRGGB10_1X10;
1847 	imx274->format.colorspace = V4L2_COLORSPACE_SRGB;
1848 	imx274->frame_interval.numerator = 1;
1849 	imx274->frame_interval.denominator = IMX274_DEF_FRAME_RATE;
1850 
1851 	/* initialize regmap */
1852 	imx274->regmap = devm_regmap_init_i2c(client, &imx274_regmap_config);
1853 	if (IS_ERR(imx274->regmap)) {
1854 		dev_err(&client->dev,
1855 			"regmap init failed: %ld\n", PTR_ERR(imx274->regmap));
1856 		ret = -ENODEV;
1857 		goto err_regmap;
1858 	}
1859 
1860 	/* initialize subdevice */
1861 	imx274->client = client;
1862 	sd = &imx274->sd;
1863 	v4l2_i2c_subdev_init(sd, client, &imx274_subdev_ops);
1864 	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
1865 
1866 	/* initialize subdev media pad */
1867 	imx274->pad.flags = MEDIA_PAD_FL_SOURCE;
1868 	sd->entity.function = MEDIA_ENT_F_CAM_SENSOR;
1869 	ret = media_entity_pads_init(&sd->entity, 1, &imx274->pad);
1870 	if (ret < 0) {
1871 		dev_err(&client->dev,
1872 			"%s : media entity init Failed %d\n", __func__, ret);
1873 		goto err_regmap;
1874 	}
1875 
1876 	/* initialize sensor reset gpio */
1877 	imx274->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
1878 						     GPIOD_OUT_HIGH);
1879 	if (IS_ERR(imx274->reset_gpio)) {
1880 		if (PTR_ERR(imx274->reset_gpio) != -EPROBE_DEFER)
1881 			dev_err(&client->dev, "Reset GPIO not setup in DT");
1882 		ret = PTR_ERR(imx274->reset_gpio);
1883 		goto err_me;
1884 	}
1885 
1886 	/* pull sensor out of reset */
1887 	imx274_reset(imx274, 1);
1888 
1889 	/* initialize controls */
1890 	ret = v4l2_ctrl_handler_init(&imx274->ctrls.handler, 4);
1891 	if (ret < 0) {
1892 		dev_err(&client->dev,
1893 			"%s : ctrl handler init Failed\n", __func__);
1894 		goto err_me;
1895 	}
1896 
1897 	imx274->ctrls.handler.lock = &imx274->lock;
1898 
1899 	/* add new controls */
1900 	imx274->ctrls.test_pattern = v4l2_ctrl_new_std_menu_items(
1901 		&imx274->ctrls.handler, &imx274_ctrl_ops,
1902 		V4L2_CID_TEST_PATTERN,
1903 		ARRAY_SIZE(tp_qmenu) - 1, 0, 0, tp_qmenu);
1904 
1905 	imx274->ctrls.gain = v4l2_ctrl_new_std(
1906 		&imx274->ctrls.handler,
1907 		&imx274_ctrl_ops,
1908 		V4L2_CID_GAIN, IMX274_MIN_GAIN,
1909 		IMX274_MAX_DIGITAL_GAIN * IMX274_MAX_ANALOG_GAIN, 1,
1910 		IMX274_DEF_GAIN);
1911 
1912 	imx274->ctrls.exposure = v4l2_ctrl_new_std(
1913 		&imx274->ctrls.handler,
1914 		&imx274_ctrl_ops,
1915 		V4L2_CID_EXPOSURE, IMX274_MIN_EXPOSURE_TIME,
1916 		1000000 / IMX274_DEF_FRAME_RATE, 1,
1917 		IMX274_MIN_EXPOSURE_TIME);
1918 
1919 	imx274->ctrls.vflip = v4l2_ctrl_new_std(
1920 		&imx274->ctrls.handler,
1921 		&imx274_ctrl_ops,
1922 		V4L2_CID_VFLIP, 0, 1, 1, 0);
1923 
1924 	imx274->sd.ctrl_handler = &imx274->ctrls.handler;
1925 	if (imx274->ctrls.handler.error) {
1926 		ret = imx274->ctrls.handler.error;
1927 		goto err_ctrls;
1928 	}
1929 
1930 	/* setup default controls */
1931 	ret = v4l2_ctrl_handler_setup(&imx274->ctrls.handler);
1932 	if (ret) {
1933 		dev_err(&client->dev,
1934 			"Error %d setup default controls\n", ret);
1935 		goto err_ctrls;
1936 	}
1937 
1938 	/* load default control values */
1939 	ret = imx274_load_default(imx274);
1940 	if (ret) {
1941 		dev_err(&client->dev,
1942 			"%s : imx274_load_default failed %d\n",
1943 			__func__, ret);
1944 		goto err_ctrls;
1945 	}
1946 
1947 	/* register subdevice */
1948 	ret = v4l2_async_register_subdev(sd);
1949 	if (ret < 0) {
1950 		dev_err(&client->dev,
1951 			"%s : v4l2_async_register_subdev failed %d\n",
1952 			__func__, ret);
1953 		goto err_ctrls;
1954 	}
1955 
1956 	dev_info(&client->dev, "imx274 : imx274 probe success !\n");
1957 	return 0;
1958 
1959 err_ctrls:
1960 	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
1961 err_me:
1962 	media_entity_cleanup(&sd->entity);
1963 err_regmap:
1964 	mutex_destroy(&imx274->lock);
1965 	return ret;
1966 }
1967 
1968 static int imx274_remove(struct i2c_client *client)
1969 {
1970 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
1971 	struct stimx274 *imx274 = to_imx274(sd);
1972 
1973 	/* stop stream */
1974 	imx274_write_table(imx274, imx274_stop);
1975 
1976 	v4l2_async_unregister_subdev(sd);
1977 	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
1978 	media_entity_cleanup(&sd->entity);
1979 	mutex_destroy(&imx274->lock);
1980 	return 0;
1981 }
1982 
1983 static struct i2c_driver imx274_i2c_driver = {
1984 	.driver = {
1985 		.name	= DRIVER_NAME,
1986 		.of_match_table	= imx274_of_id_table,
1987 	},
1988 	.probe_new	= imx274_probe,
1989 	.remove		= imx274_remove,
1990 	.id_table	= imx274_id,
1991 };
1992 
1993 module_i2c_driver(imx274_i2c_driver);
1994 
1995 MODULE_AUTHOR("Leon Luo <leonl@leopardimaging.com>");
1996 MODULE_DESCRIPTION("IMX274 CMOS Image Sensor driver");
1997 MODULE_LICENSE("GPL v2");
1998