xref: /openbmc/linux/drivers/media/i2c/ov7251.c (revision 8bd1369b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for the OV7251 camera sensor.
4  *
5  * Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
6  * Copyright (c) 2017-2018, Linaro Ltd.
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/i2c.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/slab.h>
19 #include <linux/types.h>
20 #include <media/v4l2-ctrls.h>
21 #include <media/v4l2-fwnode.h>
22 #include <media/v4l2-subdev.h>
23 
24 #define OV7251_SC_MODE_SELECT		0x0100
25 #define OV7251_SC_MODE_SELECT_SW_STANDBY	0x0
26 #define OV7251_SC_MODE_SELECT_STREAMING		0x1
27 
28 #define OV7251_CHIP_ID_HIGH		0x300a
29 #define OV7251_CHIP_ID_HIGH_BYTE	0x77
30 #define OV7251_CHIP_ID_LOW		0x300b
31 #define OV7251_CHIP_ID_LOW_BYTE		0x50
32 #define OV7251_SC_GP_IO_IN1		0x3029
33 #define OV7251_AEC_EXPO_0		0x3500
34 #define OV7251_AEC_EXPO_1		0x3501
35 #define OV7251_AEC_EXPO_2		0x3502
36 #define OV7251_AEC_AGC_ADJ_0		0x350a
37 #define OV7251_AEC_AGC_ADJ_1		0x350b
38 #define OV7251_TIMING_FORMAT1		0x3820
39 #define OV7251_TIMING_FORMAT1_VFLIP	BIT(2)
40 #define OV7251_TIMING_FORMAT2		0x3821
41 #define OV7251_TIMING_FORMAT2_MIRROR	BIT(2)
42 #define OV7251_PRE_ISP_00		0x5e00
43 #define OV7251_PRE_ISP_00_TEST_PATTERN	BIT(7)
44 
45 struct reg_value {
46 	u16 reg;
47 	u8 val;
48 };
49 
50 struct ov7251_mode_info {
51 	u32 width;
52 	u32 height;
53 	const struct reg_value *data;
54 	u32 data_size;
55 	u32 pixel_clock;
56 	u32 link_freq;
57 	u16 exposure_max;
58 	u16 exposure_def;
59 	struct v4l2_fract timeperframe;
60 };
61 
62 struct ov7251 {
63 	struct i2c_client *i2c_client;
64 	struct device *dev;
65 	struct v4l2_subdev sd;
66 	struct media_pad pad;
67 	struct v4l2_fwnode_endpoint ep;
68 	struct v4l2_mbus_framefmt fmt;
69 	struct v4l2_rect crop;
70 	struct clk *xclk;
71 	u32 xclk_freq;
72 
73 	struct regulator *io_regulator;
74 	struct regulator *core_regulator;
75 	struct regulator *analog_regulator;
76 
77 	const struct ov7251_mode_info *current_mode;
78 
79 	struct v4l2_ctrl_handler ctrls;
80 	struct v4l2_ctrl *pixel_clock;
81 	struct v4l2_ctrl *link_freq;
82 	struct v4l2_ctrl *exposure;
83 	struct v4l2_ctrl *gain;
84 
85 	/* Cached register values */
86 	u8 aec_pk_manual;
87 	u8 pre_isp_00;
88 	u8 timing_format1;
89 	u8 timing_format2;
90 
91 	struct mutex lock; /* lock to protect power state, ctrls and mode */
92 	bool power_on;
93 
94 	struct gpio_desc *enable_gpio;
95 };
96 
97 static inline struct ov7251 *to_ov7251(struct v4l2_subdev *sd)
98 {
99 	return container_of(sd, struct ov7251, sd);
100 }
101 
102 static const struct reg_value ov7251_global_init_setting[] = {
103 	{ 0x0103, 0x01 },
104 	{ 0x303b, 0x02 },
105 };
106 
107 static const struct reg_value ov7251_setting_vga_30fps[] = {
108 	{ 0x3005, 0x00 },
109 	{ 0x3012, 0xc0 },
110 	{ 0x3013, 0xd2 },
111 	{ 0x3014, 0x04 },
112 	{ 0x3016, 0xf0 },
113 	{ 0x3017, 0xf0 },
114 	{ 0x3018, 0xf0 },
115 	{ 0x301a, 0xf0 },
116 	{ 0x301b, 0xf0 },
117 	{ 0x301c, 0xf0 },
118 	{ 0x3023, 0x05 },
119 	{ 0x3037, 0xf0 },
120 	{ 0x3098, 0x04 }, /* pll2 pre divider */
121 	{ 0x3099, 0x28 }, /* pll2 multiplier */
122 	{ 0x309a, 0x05 }, /* pll2 sys divider */
123 	{ 0x309b, 0x04 }, /* pll2 adc divider */
124 	{ 0x309d, 0x00 }, /* pll2 divider */
125 	{ 0x30b0, 0x0a }, /* pll1 pix divider */
126 	{ 0x30b1, 0x01 }, /* pll1 divider */
127 	{ 0x30b3, 0x64 }, /* pll1 multiplier */
128 	{ 0x30b4, 0x03 }, /* pll1 pre divider */
129 	{ 0x30b5, 0x05 }, /* pll1 mipi divider */
130 	{ 0x3106, 0xda },
131 	{ 0x3503, 0x07 },
132 	{ 0x3509, 0x10 },
133 	{ 0x3600, 0x1c },
134 	{ 0x3602, 0x62 },
135 	{ 0x3620, 0xb7 },
136 	{ 0x3622, 0x04 },
137 	{ 0x3626, 0x21 },
138 	{ 0x3627, 0x30 },
139 	{ 0x3630, 0x44 },
140 	{ 0x3631, 0x35 },
141 	{ 0x3634, 0x60 },
142 	{ 0x3636, 0x00 },
143 	{ 0x3662, 0x01 },
144 	{ 0x3663, 0x70 },
145 	{ 0x3664, 0x50 },
146 	{ 0x3666, 0x0a },
147 	{ 0x3669, 0x1a },
148 	{ 0x366a, 0x00 },
149 	{ 0x366b, 0x50 },
150 	{ 0x3673, 0x01 },
151 	{ 0x3674, 0xff },
152 	{ 0x3675, 0x03 },
153 	{ 0x3705, 0xc1 },
154 	{ 0x3709, 0x40 },
155 	{ 0x373c, 0x08 },
156 	{ 0x3742, 0x00 },
157 	{ 0x3757, 0xb3 },
158 	{ 0x3788, 0x00 },
159 	{ 0x37a8, 0x01 },
160 	{ 0x37a9, 0xc0 },
161 	{ 0x3800, 0x00 },
162 	{ 0x3801, 0x04 },
163 	{ 0x3802, 0x00 },
164 	{ 0x3803, 0x04 },
165 	{ 0x3804, 0x02 },
166 	{ 0x3805, 0x8b },
167 	{ 0x3806, 0x01 },
168 	{ 0x3807, 0xeb },
169 	{ 0x3808, 0x02 }, /* width high */
170 	{ 0x3809, 0x80 }, /* width low */
171 	{ 0x380a, 0x01 }, /* height high */
172 	{ 0x380b, 0xe0 }, /* height low */
173 	{ 0x380c, 0x03 }, /* total horiz timing high */
174 	{ 0x380d, 0xa0 }, /* total horiz timing low */
175 	{ 0x380e, 0x06 }, /* total vertical timing high */
176 	{ 0x380f, 0xbc }, /* total vertical timing low */
177 	{ 0x3810, 0x00 },
178 	{ 0x3811, 0x04 },
179 	{ 0x3812, 0x00 },
180 	{ 0x3813, 0x05 },
181 	{ 0x3814, 0x11 },
182 	{ 0x3815, 0x11 },
183 	{ 0x3820, 0x40 },
184 	{ 0x3821, 0x00 },
185 	{ 0x382f, 0x0e },
186 	{ 0x3832, 0x00 },
187 	{ 0x3833, 0x05 },
188 	{ 0x3834, 0x00 },
189 	{ 0x3835, 0x0c },
190 	{ 0x3837, 0x00 },
191 	{ 0x3b80, 0x00 },
192 	{ 0x3b81, 0xa5 },
193 	{ 0x3b82, 0x10 },
194 	{ 0x3b83, 0x00 },
195 	{ 0x3b84, 0x08 },
196 	{ 0x3b85, 0x00 },
197 	{ 0x3b86, 0x01 },
198 	{ 0x3b87, 0x00 },
199 	{ 0x3b88, 0x00 },
200 	{ 0x3b89, 0x00 },
201 	{ 0x3b8a, 0x00 },
202 	{ 0x3b8b, 0x05 },
203 	{ 0x3b8c, 0x00 },
204 	{ 0x3b8d, 0x00 },
205 	{ 0x3b8e, 0x00 },
206 	{ 0x3b8f, 0x1a },
207 	{ 0x3b94, 0x05 },
208 	{ 0x3b95, 0xf2 },
209 	{ 0x3b96, 0x40 },
210 	{ 0x3c00, 0x89 },
211 	{ 0x3c01, 0x63 },
212 	{ 0x3c02, 0x01 },
213 	{ 0x3c03, 0x00 },
214 	{ 0x3c04, 0x00 },
215 	{ 0x3c05, 0x03 },
216 	{ 0x3c06, 0x00 },
217 	{ 0x3c07, 0x06 },
218 	{ 0x3c0c, 0x01 },
219 	{ 0x3c0d, 0xd0 },
220 	{ 0x3c0e, 0x02 },
221 	{ 0x3c0f, 0x0a },
222 	{ 0x4001, 0x42 },
223 	{ 0x4004, 0x04 },
224 	{ 0x4005, 0x00 },
225 	{ 0x404e, 0x01 },
226 	{ 0x4300, 0xff },
227 	{ 0x4301, 0x00 },
228 	{ 0x4315, 0x00 },
229 	{ 0x4501, 0x48 },
230 	{ 0x4600, 0x00 },
231 	{ 0x4601, 0x4e },
232 	{ 0x4801, 0x0f },
233 	{ 0x4806, 0x0f },
234 	{ 0x4819, 0xaa },
235 	{ 0x4823, 0x3e },
236 	{ 0x4837, 0x19 },
237 	{ 0x4a0d, 0x00 },
238 	{ 0x4a47, 0x7f },
239 	{ 0x4a49, 0xf0 },
240 	{ 0x4a4b, 0x30 },
241 	{ 0x5000, 0x85 },
242 	{ 0x5001, 0x80 },
243 };
244 
245 static const struct reg_value ov7251_setting_vga_60fps[] = {
246 	{ 0x3005, 0x00 },
247 	{ 0x3012, 0xc0 },
248 	{ 0x3013, 0xd2 },
249 	{ 0x3014, 0x04 },
250 	{ 0x3016, 0x10 },
251 	{ 0x3017, 0x00 },
252 	{ 0x3018, 0x00 },
253 	{ 0x301a, 0x00 },
254 	{ 0x301b, 0x00 },
255 	{ 0x301c, 0x00 },
256 	{ 0x3023, 0x05 },
257 	{ 0x3037, 0xf0 },
258 	{ 0x3098, 0x04 }, /* pll2 pre divider */
259 	{ 0x3099, 0x28 }, /* pll2 multiplier */
260 	{ 0x309a, 0x05 }, /* pll2 sys divider */
261 	{ 0x309b, 0x04 }, /* pll2 adc divider */
262 	{ 0x309d, 0x00 }, /* pll2 divider */
263 	{ 0x30b0, 0x0a }, /* pll1 pix divider */
264 	{ 0x30b1, 0x01 }, /* pll1 divider */
265 	{ 0x30b3, 0x64 }, /* pll1 multiplier */
266 	{ 0x30b4, 0x03 }, /* pll1 pre divider */
267 	{ 0x30b5, 0x05 }, /* pll1 mipi divider */
268 	{ 0x3106, 0xda },
269 	{ 0x3503, 0x07 },
270 	{ 0x3509, 0x10 },
271 	{ 0x3600, 0x1c },
272 	{ 0x3602, 0x62 },
273 	{ 0x3620, 0xb7 },
274 	{ 0x3622, 0x04 },
275 	{ 0x3626, 0x21 },
276 	{ 0x3627, 0x30 },
277 	{ 0x3630, 0x44 },
278 	{ 0x3631, 0x35 },
279 	{ 0x3634, 0x60 },
280 	{ 0x3636, 0x00 },
281 	{ 0x3662, 0x01 },
282 	{ 0x3663, 0x70 },
283 	{ 0x3664, 0x50 },
284 	{ 0x3666, 0x0a },
285 	{ 0x3669, 0x1a },
286 	{ 0x366a, 0x00 },
287 	{ 0x366b, 0x50 },
288 	{ 0x3673, 0x01 },
289 	{ 0x3674, 0xff },
290 	{ 0x3675, 0x03 },
291 	{ 0x3705, 0xc1 },
292 	{ 0x3709, 0x40 },
293 	{ 0x373c, 0x08 },
294 	{ 0x3742, 0x00 },
295 	{ 0x3757, 0xb3 },
296 	{ 0x3788, 0x00 },
297 	{ 0x37a8, 0x01 },
298 	{ 0x37a9, 0xc0 },
299 	{ 0x3800, 0x00 },
300 	{ 0x3801, 0x04 },
301 	{ 0x3802, 0x00 },
302 	{ 0x3803, 0x04 },
303 	{ 0x3804, 0x02 },
304 	{ 0x3805, 0x8b },
305 	{ 0x3806, 0x01 },
306 	{ 0x3807, 0xeb },
307 	{ 0x3808, 0x02 }, /* width high */
308 	{ 0x3809, 0x80 }, /* width low */
309 	{ 0x380a, 0x01 }, /* height high */
310 	{ 0x380b, 0xe0 }, /* height low */
311 	{ 0x380c, 0x03 }, /* total horiz timing high */
312 	{ 0x380d, 0xa0 }, /* total horiz timing low */
313 	{ 0x380e, 0x03 }, /* total vertical timing high */
314 	{ 0x380f, 0x5c }, /* total vertical timing low */
315 	{ 0x3810, 0x00 },
316 	{ 0x3811, 0x04 },
317 	{ 0x3812, 0x00 },
318 	{ 0x3813, 0x05 },
319 	{ 0x3814, 0x11 },
320 	{ 0x3815, 0x11 },
321 	{ 0x3820, 0x40 },
322 	{ 0x3821, 0x00 },
323 	{ 0x382f, 0x0e },
324 	{ 0x3832, 0x00 },
325 	{ 0x3833, 0x05 },
326 	{ 0x3834, 0x00 },
327 	{ 0x3835, 0x0c },
328 	{ 0x3837, 0x00 },
329 	{ 0x3b80, 0x00 },
330 	{ 0x3b81, 0xa5 },
331 	{ 0x3b82, 0x10 },
332 	{ 0x3b83, 0x00 },
333 	{ 0x3b84, 0x08 },
334 	{ 0x3b85, 0x00 },
335 	{ 0x3b86, 0x01 },
336 	{ 0x3b87, 0x00 },
337 	{ 0x3b88, 0x00 },
338 	{ 0x3b89, 0x00 },
339 	{ 0x3b8a, 0x00 },
340 	{ 0x3b8b, 0x05 },
341 	{ 0x3b8c, 0x00 },
342 	{ 0x3b8d, 0x00 },
343 	{ 0x3b8e, 0x00 },
344 	{ 0x3b8f, 0x1a },
345 	{ 0x3b94, 0x05 },
346 	{ 0x3b95, 0xf2 },
347 	{ 0x3b96, 0x40 },
348 	{ 0x3c00, 0x89 },
349 	{ 0x3c01, 0x63 },
350 	{ 0x3c02, 0x01 },
351 	{ 0x3c03, 0x00 },
352 	{ 0x3c04, 0x00 },
353 	{ 0x3c05, 0x03 },
354 	{ 0x3c06, 0x00 },
355 	{ 0x3c07, 0x06 },
356 	{ 0x3c0c, 0x01 },
357 	{ 0x3c0d, 0xd0 },
358 	{ 0x3c0e, 0x02 },
359 	{ 0x3c0f, 0x0a },
360 	{ 0x4001, 0x42 },
361 	{ 0x4004, 0x04 },
362 	{ 0x4005, 0x00 },
363 	{ 0x404e, 0x01 },
364 	{ 0x4300, 0xff },
365 	{ 0x4301, 0x00 },
366 	{ 0x4315, 0x00 },
367 	{ 0x4501, 0x48 },
368 	{ 0x4600, 0x00 },
369 	{ 0x4601, 0x4e },
370 	{ 0x4801, 0x0f },
371 	{ 0x4806, 0x0f },
372 	{ 0x4819, 0xaa },
373 	{ 0x4823, 0x3e },
374 	{ 0x4837, 0x19 },
375 	{ 0x4a0d, 0x00 },
376 	{ 0x4a47, 0x7f },
377 	{ 0x4a49, 0xf0 },
378 	{ 0x4a4b, 0x30 },
379 	{ 0x5000, 0x85 },
380 	{ 0x5001, 0x80 },
381 };
382 
383 static const struct reg_value ov7251_setting_vga_90fps[] = {
384 	{ 0x3005, 0x00 },
385 	{ 0x3012, 0xc0 },
386 	{ 0x3013, 0xd2 },
387 	{ 0x3014, 0x04 },
388 	{ 0x3016, 0x10 },
389 	{ 0x3017, 0x00 },
390 	{ 0x3018, 0x00 },
391 	{ 0x301a, 0x00 },
392 	{ 0x301b, 0x00 },
393 	{ 0x301c, 0x00 },
394 	{ 0x3023, 0x05 },
395 	{ 0x3037, 0xf0 },
396 	{ 0x3098, 0x04 }, /* pll2 pre divider */
397 	{ 0x3099, 0x28 }, /* pll2 multiplier */
398 	{ 0x309a, 0x05 }, /* pll2 sys divider */
399 	{ 0x309b, 0x04 }, /* pll2 adc divider */
400 	{ 0x309d, 0x00 }, /* pll2 divider */
401 	{ 0x30b0, 0x0a }, /* pll1 pix divider */
402 	{ 0x30b1, 0x01 }, /* pll1 divider */
403 	{ 0x30b3, 0x64 }, /* pll1 multiplier */
404 	{ 0x30b4, 0x03 }, /* pll1 pre divider */
405 	{ 0x30b5, 0x05 }, /* pll1 mipi divider */
406 	{ 0x3106, 0xda },
407 	{ 0x3503, 0x07 },
408 	{ 0x3509, 0x10 },
409 	{ 0x3600, 0x1c },
410 	{ 0x3602, 0x62 },
411 	{ 0x3620, 0xb7 },
412 	{ 0x3622, 0x04 },
413 	{ 0x3626, 0x21 },
414 	{ 0x3627, 0x30 },
415 	{ 0x3630, 0x44 },
416 	{ 0x3631, 0x35 },
417 	{ 0x3634, 0x60 },
418 	{ 0x3636, 0x00 },
419 	{ 0x3662, 0x01 },
420 	{ 0x3663, 0x70 },
421 	{ 0x3664, 0x50 },
422 	{ 0x3666, 0x0a },
423 	{ 0x3669, 0x1a },
424 	{ 0x366a, 0x00 },
425 	{ 0x366b, 0x50 },
426 	{ 0x3673, 0x01 },
427 	{ 0x3674, 0xff },
428 	{ 0x3675, 0x03 },
429 	{ 0x3705, 0xc1 },
430 	{ 0x3709, 0x40 },
431 	{ 0x373c, 0x08 },
432 	{ 0x3742, 0x00 },
433 	{ 0x3757, 0xb3 },
434 	{ 0x3788, 0x00 },
435 	{ 0x37a8, 0x01 },
436 	{ 0x37a9, 0xc0 },
437 	{ 0x3800, 0x00 },
438 	{ 0x3801, 0x04 },
439 	{ 0x3802, 0x00 },
440 	{ 0x3803, 0x04 },
441 	{ 0x3804, 0x02 },
442 	{ 0x3805, 0x8b },
443 	{ 0x3806, 0x01 },
444 	{ 0x3807, 0xeb },
445 	{ 0x3808, 0x02 }, /* width high */
446 	{ 0x3809, 0x80 }, /* width low */
447 	{ 0x380a, 0x01 }, /* height high */
448 	{ 0x380b, 0xe0 }, /* height low */
449 	{ 0x380c, 0x03 }, /* total horiz timing high */
450 	{ 0x380d, 0xa0 }, /* total horiz timing low */
451 	{ 0x380e, 0x02 }, /* total vertical timing high */
452 	{ 0x380f, 0x3c }, /* total vertical timing low */
453 	{ 0x3810, 0x00 },
454 	{ 0x3811, 0x04 },
455 	{ 0x3812, 0x00 },
456 	{ 0x3813, 0x05 },
457 	{ 0x3814, 0x11 },
458 	{ 0x3815, 0x11 },
459 	{ 0x3820, 0x40 },
460 	{ 0x3821, 0x00 },
461 	{ 0x382f, 0x0e },
462 	{ 0x3832, 0x00 },
463 	{ 0x3833, 0x05 },
464 	{ 0x3834, 0x00 },
465 	{ 0x3835, 0x0c },
466 	{ 0x3837, 0x00 },
467 	{ 0x3b80, 0x00 },
468 	{ 0x3b81, 0xa5 },
469 	{ 0x3b82, 0x10 },
470 	{ 0x3b83, 0x00 },
471 	{ 0x3b84, 0x08 },
472 	{ 0x3b85, 0x00 },
473 	{ 0x3b86, 0x01 },
474 	{ 0x3b87, 0x00 },
475 	{ 0x3b88, 0x00 },
476 	{ 0x3b89, 0x00 },
477 	{ 0x3b8a, 0x00 },
478 	{ 0x3b8b, 0x05 },
479 	{ 0x3b8c, 0x00 },
480 	{ 0x3b8d, 0x00 },
481 	{ 0x3b8e, 0x00 },
482 	{ 0x3b8f, 0x1a },
483 	{ 0x3b94, 0x05 },
484 	{ 0x3b95, 0xf2 },
485 	{ 0x3b96, 0x40 },
486 	{ 0x3c00, 0x89 },
487 	{ 0x3c01, 0x63 },
488 	{ 0x3c02, 0x01 },
489 	{ 0x3c03, 0x00 },
490 	{ 0x3c04, 0x00 },
491 	{ 0x3c05, 0x03 },
492 	{ 0x3c06, 0x00 },
493 	{ 0x3c07, 0x06 },
494 	{ 0x3c0c, 0x01 },
495 	{ 0x3c0d, 0xd0 },
496 	{ 0x3c0e, 0x02 },
497 	{ 0x3c0f, 0x0a },
498 	{ 0x4001, 0x42 },
499 	{ 0x4004, 0x04 },
500 	{ 0x4005, 0x00 },
501 	{ 0x404e, 0x01 },
502 	{ 0x4300, 0xff },
503 	{ 0x4301, 0x00 },
504 	{ 0x4315, 0x00 },
505 	{ 0x4501, 0x48 },
506 	{ 0x4600, 0x00 },
507 	{ 0x4601, 0x4e },
508 	{ 0x4801, 0x0f },
509 	{ 0x4806, 0x0f },
510 	{ 0x4819, 0xaa },
511 	{ 0x4823, 0x3e },
512 	{ 0x4837, 0x19 },
513 	{ 0x4a0d, 0x00 },
514 	{ 0x4a47, 0x7f },
515 	{ 0x4a49, 0xf0 },
516 	{ 0x4a4b, 0x30 },
517 	{ 0x5000, 0x85 },
518 	{ 0x5001, 0x80 },
519 };
520 
521 static const s64 link_freq[] = {
522 	240000000,
523 };
524 
525 static const struct ov7251_mode_info ov7251_mode_info_data[] = {
526 	{
527 		.width = 640,
528 		.height = 480,
529 		.data = ov7251_setting_vga_30fps,
530 		.data_size = ARRAY_SIZE(ov7251_setting_vga_30fps),
531 		.pixel_clock = 48000000,
532 		.link_freq = 0, /* an index in link_freq[] */
533 		.exposure_max = 1704,
534 		.exposure_def = 504,
535 		.timeperframe = {
536 			.numerator = 100,
537 			.denominator = 3000
538 		}
539 	},
540 	{
541 		.width = 640,
542 		.height = 480,
543 		.data = ov7251_setting_vga_60fps,
544 		.data_size = ARRAY_SIZE(ov7251_setting_vga_60fps),
545 		.pixel_clock = 48000000,
546 		.link_freq = 0, /* an index in link_freq[] */
547 		.exposure_max = 840,
548 		.exposure_def = 504,
549 		.timeperframe = {
550 			.numerator = 100,
551 			.denominator = 6014
552 		}
553 	},
554 	{
555 		.width = 640,
556 		.height = 480,
557 		.data = ov7251_setting_vga_90fps,
558 		.data_size = ARRAY_SIZE(ov7251_setting_vga_90fps),
559 		.pixel_clock = 48000000,
560 		.link_freq = 0, /* an index in link_freq[] */
561 		.exposure_max = 552,
562 		.exposure_def = 504,
563 		.timeperframe = {
564 			.numerator = 100,
565 			.denominator = 9043
566 		}
567 	},
568 };
569 
570 static int ov7251_regulators_enable(struct ov7251 *ov7251)
571 {
572 	int ret;
573 
574 	/* OV7251 power up sequence requires core regulator
575 	 * to be enabled not earlier than io regulator
576 	 */
577 
578 	ret = regulator_enable(ov7251->io_regulator);
579 	if (ret < 0) {
580 		dev_err(ov7251->dev, "set io voltage failed\n");
581 		return ret;
582 	}
583 
584 	ret = regulator_enable(ov7251->analog_regulator);
585 	if (ret) {
586 		dev_err(ov7251->dev, "set analog voltage failed\n");
587 		goto err_disable_io;
588 	}
589 
590 	ret = regulator_enable(ov7251->core_regulator);
591 	if (ret) {
592 		dev_err(ov7251->dev, "set core voltage failed\n");
593 		goto err_disable_analog;
594 	}
595 
596 	return 0;
597 
598 err_disable_analog:
599 	regulator_disable(ov7251->analog_regulator);
600 
601 err_disable_io:
602 	regulator_disable(ov7251->io_regulator);
603 
604 	return ret;
605 }
606 
607 static void ov7251_regulators_disable(struct ov7251 *ov7251)
608 {
609 	int ret;
610 
611 	ret = regulator_disable(ov7251->core_regulator);
612 	if (ret < 0)
613 		dev_err(ov7251->dev, "core regulator disable failed\n");
614 
615 	ret = regulator_disable(ov7251->analog_regulator);
616 	if (ret < 0)
617 		dev_err(ov7251->dev, "analog regulator disable failed\n");
618 
619 	ret = regulator_disable(ov7251->io_regulator);
620 	if (ret < 0)
621 		dev_err(ov7251->dev, "io regulator disable failed\n");
622 }
623 
624 static int ov7251_write_reg(struct ov7251 *ov7251, u16 reg, u8 val)
625 {
626 	u8 regbuf[3];
627 	int ret;
628 
629 	regbuf[0] = reg >> 8;
630 	regbuf[1] = reg & 0xff;
631 	regbuf[2] = val;
632 
633 	ret = i2c_master_send(ov7251->i2c_client, regbuf, 3);
634 	if (ret < 0) {
635 		dev_err(ov7251->dev, "%s: write reg error %d: reg=%x, val=%x\n",
636 			__func__, ret, reg, val);
637 		return ret;
638 	}
639 
640 	return 0;
641 }
642 
643 static int ov7251_write_seq_regs(struct ov7251 *ov7251, u16 reg, u8 *val,
644 				 u8 num)
645 {
646 	u8 regbuf[5];
647 	u8 nregbuf = sizeof(reg) + num * sizeof(*val);
648 	int ret = 0;
649 
650 	if (nregbuf > sizeof(regbuf))
651 		return -EINVAL;
652 
653 	regbuf[0] = reg >> 8;
654 	regbuf[1] = reg & 0xff;
655 
656 	memcpy(regbuf + 2, val, num);
657 
658 	ret = i2c_master_send(ov7251->i2c_client, regbuf, nregbuf);
659 	if (ret < 0) {
660 		dev_err(ov7251->dev,
661 			"%s: write seq regs error %d: first reg=%x\n",
662 			__func__, ret, reg);
663 		return ret;
664 	}
665 
666 	return 0;
667 }
668 
669 static int ov7251_read_reg(struct ov7251 *ov7251, u16 reg, u8 *val)
670 {
671 	u8 regbuf[2];
672 	int ret;
673 
674 	regbuf[0] = reg >> 8;
675 	regbuf[1] = reg & 0xff;
676 
677 	ret = i2c_master_send(ov7251->i2c_client, regbuf, 2);
678 	if (ret < 0) {
679 		dev_err(ov7251->dev, "%s: write reg error %d: reg=%x\n",
680 			__func__, ret, reg);
681 		return ret;
682 	}
683 
684 	ret = i2c_master_recv(ov7251->i2c_client, val, 1);
685 	if (ret < 0) {
686 		dev_err(ov7251->dev, "%s: read reg error %d: reg=%x\n",
687 			__func__, ret, reg);
688 		return ret;
689 	}
690 
691 	return 0;
692 }
693 
694 static int ov7251_set_exposure(struct ov7251 *ov7251, s32 exposure)
695 {
696 	u16 reg;
697 	u8 val[3];
698 
699 	reg = OV7251_AEC_EXPO_0;
700 	val[0] = (exposure & 0xf000) >> 12; /* goes to OV7251_AEC_EXPO_0 */
701 	val[1] = (exposure & 0x0ff0) >> 4;  /* goes to OV7251_AEC_EXPO_1 */
702 	val[2] = (exposure & 0x000f) << 4;  /* goes to OV7251_AEC_EXPO_2 */
703 
704 	return ov7251_write_seq_regs(ov7251, reg, val, 3);
705 }
706 
707 static int ov7251_set_gain(struct ov7251 *ov7251, s32 gain)
708 {
709 	u16 reg;
710 	u8 val[2];
711 
712 	reg = OV7251_AEC_AGC_ADJ_0;
713 	val[0] = (gain & 0x0300) >> 8; /* goes to OV7251_AEC_AGC_ADJ_0 */
714 	val[1] = gain & 0xff;          /* goes to OV7251_AEC_AGC_ADJ_1 */
715 
716 	return ov7251_write_seq_regs(ov7251, reg, val, 2);
717 }
718 
719 static int ov7251_set_register_array(struct ov7251 *ov7251,
720 				     const struct reg_value *settings,
721 				     unsigned int num_settings)
722 {
723 	unsigned int i;
724 	int ret;
725 
726 	for (i = 0; i < num_settings; ++i, ++settings) {
727 		ret = ov7251_write_reg(ov7251, settings->reg, settings->val);
728 		if (ret < 0)
729 			return ret;
730 	}
731 
732 	return 0;
733 }
734 
735 static int ov7251_set_power_on(struct ov7251 *ov7251)
736 {
737 	int ret;
738 	u32 wait_us;
739 
740 	ret = ov7251_regulators_enable(ov7251);
741 	if (ret < 0)
742 		return ret;
743 
744 	ret = clk_prepare_enable(ov7251->xclk);
745 	if (ret < 0) {
746 		dev_err(ov7251->dev, "clk prepare enable failed\n");
747 		ov7251_regulators_disable(ov7251);
748 		return ret;
749 	}
750 
751 	gpiod_set_value_cansleep(ov7251->enable_gpio, 1);
752 
753 	/* wait at least 65536 external clock cycles */
754 	wait_us = DIV_ROUND_UP(65536 * 1000,
755 			       DIV_ROUND_UP(ov7251->xclk_freq, 1000));
756 	usleep_range(wait_us, wait_us + 1000);
757 
758 	return 0;
759 }
760 
761 static void ov7251_set_power_off(struct ov7251 *ov7251)
762 {
763 	clk_disable_unprepare(ov7251->xclk);
764 	gpiod_set_value_cansleep(ov7251->enable_gpio, 0);
765 	ov7251_regulators_disable(ov7251);
766 }
767 
768 static int ov7251_s_power(struct v4l2_subdev *sd, int on)
769 {
770 	struct ov7251 *ov7251 = to_ov7251(sd);
771 	int ret = 0;
772 
773 	mutex_lock(&ov7251->lock);
774 
775 	/* If the power state is not modified - no work to do. */
776 	if (ov7251->power_on == !!on)
777 		goto exit;
778 
779 	if (on) {
780 		ret = ov7251_set_power_on(ov7251);
781 		if (ret < 0)
782 			goto exit;
783 
784 		ret = ov7251_set_register_array(ov7251,
785 					ov7251_global_init_setting,
786 					ARRAY_SIZE(ov7251_global_init_setting));
787 		if (ret < 0) {
788 			dev_err(ov7251->dev, "could not set init registers\n");
789 			ov7251_set_power_off(ov7251);
790 			goto exit;
791 		}
792 
793 		ov7251->power_on = true;
794 	} else {
795 		ov7251_set_power_off(ov7251);
796 		ov7251->power_on = false;
797 	}
798 
799 exit:
800 	mutex_unlock(&ov7251->lock);
801 
802 	return ret;
803 }
804 
805 static int ov7251_set_hflip(struct ov7251 *ov7251, s32 value)
806 {
807 	u8 val = ov7251->timing_format2;
808 	int ret;
809 
810 	if (value)
811 		val |= OV7251_TIMING_FORMAT2_MIRROR;
812 	else
813 		val &= ~OV7251_TIMING_FORMAT2_MIRROR;
814 
815 	ret = ov7251_write_reg(ov7251, OV7251_TIMING_FORMAT2, val);
816 	if (!ret)
817 		ov7251->timing_format2 = val;
818 
819 	return ret;
820 }
821 
822 static int ov7251_set_vflip(struct ov7251 *ov7251, s32 value)
823 {
824 	u8 val = ov7251->timing_format1;
825 	int ret;
826 
827 	if (value)
828 		val |= OV7251_TIMING_FORMAT1_VFLIP;
829 	else
830 		val &= ~OV7251_TIMING_FORMAT1_VFLIP;
831 
832 	ret = ov7251_write_reg(ov7251, OV7251_TIMING_FORMAT1, val);
833 	if (!ret)
834 		ov7251->timing_format1 = val;
835 
836 	return ret;
837 }
838 
839 static int ov7251_set_test_pattern(struct ov7251 *ov7251, s32 value)
840 {
841 	u8 val = ov7251->pre_isp_00;
842 	int ret;
843 
844 	if (value)
845 		val |= OV7251_PRE_ISP_00_TEST_PATTERN;
846 	else
847 		val &= ~OV7251_PRE_ISP_00_TEST_PATTERN;
848 
849 	ret = ov7251_write_reg(ov7251, OV7251_PRE_ISP_00, val);
850 	if (!ret)
851 		ov7251->pre_isp_00 = val;
852 
853 	return ret;
854 }
855 
856 static const char * const ov7251_test_pattern_menu[] = {
857 	"Disabled",
858 	"Vertical Pattern Bars",
859 };
860 
861 static int ov7251_s_ctrl(struct v4l2_ctrl *ctrl)
862 {
863 	struct ov7251 *ov7251 = container_of(ctrl->handler,
864 					     struct ov7251, ctrls);
865 	int ret;
866 
867 	/* v4l2_ctrl_lock() locks our mutex */
868 
869 	if (!ov7251->power_on)
870 		return 0;
871 
872 	switch (ctrl->id) {
873 	case V4L2_CID_EXPOSURE:
874 		ret = ov7251_set_exposure(ov7251, ctrl->val);
875 		break;
876 	case V4L2_CID_GAIN:
877 		ret = ov7251_set_gain(ov7251, ctrl->val);
878 		break;
879 	case V4L2_CID_TEST_PATTERN:
880 		ret = ov7251_set_test_pattern(ov7251, ctrl->val);
881 		break;
882 	case V4L2_CID_HFLIP:
883 		ret = ov7251_set_hflip(ov7251, ctrl->val);
884 		break;
885 	case V4L2_CID_VFLIP:
886 		ret = ov7251_set_vflip(ov7251, ctrl->val);
887 		break;
888 	default:
889 		ret = -EINVAL;
890 		break;
891 	}
892 
893 	return ret;
894 }
895 
896 static const struct v4l2_ctrl_ops ov7251_ctrl_ops = {
897 	.s_ctrl = ov7251_s_ctrl,
898 };
899 
900 static int ov7251_enum_mbus_code(struct v4l2_subdev *sd,
901 				 struct v4l2_subdev_pad_config *cfg,
902 				 struct v4l2_subdev_mbus_code_enum *code)
903 {
904 	if (code->index > 0)
905 		return -EINVAL;
906 
907 	code->code = MEDIA_BUS_FMT_Y10_1X10;
908 
909 	return 0;
910 }
911 
912 static int ov7251_enum_frame_size(struct v4l2_subdev *subdev,
913 				  struct v4l2_subdev_pad_config *cfg,
914 				  struct v4l2_subdev_frame_size_enum *fse)
915 {
916 	if (fse->code != MEDIA_BUS_FMT_Y10_1X10)
917 		return -EINVAL;
918 
919 	if (fse->index >= ARRAY_SIZE(ov7251_mode_info_data))
920 		return -EINVAL;
921 
922 	fse->min_width = ov7251_mode_info_data[fse->index].width;
923 	fse->max_width = ov7251_mode_info_data[fse->index].width;
924 	fse->min_height = ov7251_mode_info_data[fse->index].height;
925 	fse->max_height = ov7251_mode_info_data[fse->index].height;
926 
927 	return 0;
928 }
929 
930 static int ov7251_enum_frame_ival(struct v4l2_subdev *subdev,
931 				  struct v4l2_subdev_pad_config *cfg,
932 				  struct v4l2_subdev_frame_interval_enum *fie)
933 {
934 	unsigned int index = fie->index;
935 	unsigned int i;
936 
937 	for (i = 0; i < ARRAY_SIZE(ov7251_mode_info_data); i++) {
938 		if (fie->width != ov7251_mode_info_data[i].width ||
939 		    fie->height != ov7251_mode_info_data[i].height)
940 			continue;
941 
942 		if (index-- == 0) {
943 			fie->interval = ov7251_mode_info_data[i].timeperframe;
944 			return 0;
945 		}
946 	}
947 
948 	return -EINVAL;
949 }
950 
951 static struct v4l2_mbus_framefmt *
952 __ov7251_get_pad_format(struct ov7251 *ov7251,
953 			struct v4l2_subdev_pad_config *cfg,
954 			unsigned int pad,
955 			enum v4l2_subdev_format_whence which)
956 {
957 	switch (which) {
958 	case V4L2_SUBDEV_FORMAT_TRY:
959 		return v4l2_subdev_get_try_format(&ov7251->sd, cfg, pad);
960 	case V4L2_SUBDEV_FORMAT_ACTIVE:
961 		return &ov7251->fmt;
962 	default:
963 		return NULL;
964 	}
965 }
966 
967 static int ov7251_get_format(struct v4l2_subdev *sd,
968 			     struct v4l2_subdev_pad_config *cfg,
969 			     struct v4l2_subdev_format *format)
970 {
971 	struct ov7251 *ov7251 = to_ov7251(sd);
972 
973 	mutex_lock(&ov7251->lock);
974 	format->format = *__ov7251_get_pad_format(ov7251, cfg, format->pad,
975 						  format->which);
976 	mutex_unlock(&ov7251->lock);
977 
978 	return 0;
979 }
980 
981 static struct v4l2_rect *
982 __ov7251_get_pad_crop(struct ov7251 *ov7251, struct v4l2_subdev_pad_config *cfg,
983 		      unsigned int pad, enum v4l2_subdev_format_whence which)
984 {
985 	switch (which) {
986 	case V4L2_SUBDEV_FORMAT_TRY:
987 		return v4l2_subdev_get_try_crop(&ov7251->sd, cfg, pad);
988 	case V4L2_SUBDEV_FORMAT_ACTIVE:
989 		return &ov7251->crop;
990 	default:
991 		return NULL;
992 	}
993 }
994 
995 static inline u32 avg_fps(const struct v4l2_fract *t)
996 {
997 	return (t->denominator + (t->numerator >> 1)) / t->numerator;
998 }
999 
1000 static const struct ov7251_mode_info *
1001 ov7251_find_mode_by_ival(struct ov7251 *ov7251, struct v4l2_fract *timeperframe)
1002 {
1003 	const struct ov7251_mode_info *mode = ov7251->current_mode;
1004 	unsigned int fps_req = avg_fps(timeperframe);
1005 	unsigned int max_dist_match = (unsigned int) -1;
1006 	unsigned int i, n = 0;
1007 
1008 	for (i = 0; i < ARRAY_SIZE(ov7251_mode_info_data); i++) {
1009 		unsigned int dist;
1010 		unsigned int fps_tmp;
1011 
1012 		if (mode->width != ov7251_mode_info_data[i].width ||
1013 		    mode->height != ov7251_mode_info_data[i].height)
1014 			continue;
1015 
1016 		fps_tmp = avg_fps(&ov7251_mode_info_data[i].timeperframe);
1017 
1018 		dist = abs(fps_req - fps_tmp);
1019 
1020 		if (dist < max_dist_match) {
1021 			n = i;
1022 			max_dist_match = dist;
1023 		}
1024 	}
1025 
1026 	return &ov7251_mode_info_data[n];
1027 }
1028 
1029 static int ov7251_set_format(struct v4l2_subdev *sd,
1030 			     struct v4l2_subdev_pad_config *cfg,
1031 			     struct v4l2_subdev_format *format)
1032 {
1033 	struct ov7251 *ov7251 = to_ov7251(sd);
1034 	struct v4l2_mbus_framefmt *__format;
1035 	struct v4l2_rect *__crop;
1036 	const struct ov7251_mode_info *new_mode;
1037 	int ret = 0;
1038 
1039 	mutex_lock(&ov7251->lock);
1040 
1041 	__crop = __ov7251_get_pad_crop(ov7251, cfg, format->pad, format->which);
1042 
1043 	new_mode = v4l2_find_nearest_size(ov7251_mode_info_data,
1044 				ARRAY_SIZE(ov7251_mode_info_data),
1045 				width, height,
1046 				format->format.width, format->format.height);
1047 
1048 	__crop->width = new_mode->width;
1049 	__crop->height = new_mode->height;
1050 
1051 	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
1052 		ret = __v4l2_ctrl_s_ctrl_int64(ov7251->pixel_clock,
1053 					       new_mode->pixel_clock);
1054 		if (ret < 0)
1055 			goto exit;
1056 
1057 		ret = __v4l2_ctrl_s_ctrl(ov7251->link_freq,
1058 					 new_mode->link_freq);
1059 		if (ret < 0)
1060 			goto exit;
1061 
1062 		ret = __v4l2_ctrl_modify_range(ov7251->exposure,
1063 					       1, new_mode->exposure_max,
1064 					       1, new_mode->exposure_def);
1065 		if (ret < 0)
1066 			goto exit;
1067 
1068 		ret = __v4l2_ctrl_s_ctrl(ov7251->exposure,
1069 					 new_mode->exposure_def);
1070 		if (ret < 0)
1071 			goto exit;
1072 
1073 		ret = __v4l2_ctrl_s_ctrl(ov7251->gain, 16);
1074 		if (ret < 0)
1075 			goto exit;
1076 
1077 		ov7251->current_mode = new_mode;
1078 	}
1079 
1080 	__format = __ov7251_get_pad_format(ov7251, cfg, format->pad,
1081 					   format->which);
1082 	__format->width = __crop->width;
1083 	__format->height = __crop->height;
1084 	__format->code = MEDIA_BUS_FMT_Y10_1X10;
1085 	__format->field = V4L2_FIELD_NONE;
1086 	__format->colorspace = V4L2_COLORSPACE_SRGB;
1087 	__format->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(__format->colorspace);
1088 	__format->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
1089 				__format->colorspace, __format->ycbcr_enc);
1090 	__format->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(__format->colorspace);
1091 
1092 	format->format = *__format;
1093 
1094 exit:
1095 	mutex_unlock(&ov7251->lock);
1096 
1097 	return ret;
1098 }
1099 
1100 static int ov7251_entity_init_cfg(struct v4l2_subdev *subdev,
1101 				  struct v4l2_subdev_pad_config *cfg)
1102 {
1103 	struct v4l2_subdev_format fmt = {
1104 		.which = cfg ? V4L2_SUBDEV_FORMAT_TRY
1105 			     : V4L2_SUBDEV_FORMAT_ACTIVE,
1106 		.format = {
1107 			.width = 640,
1108 			.height = 480
1109 		}
1110 	};
1111 
1112 	ov7251_set_format(subdev, cfg, &fmt);
1113 
1114 	return 0;
1115 }
1116 
1117 static int ov7251_get_selection(struct v4l2_subdev *sd,
1118 				struct v4l2_subdev_pad_config *cfg,
1119 				struct v4l2_subdev_selection *sel)
1120 {
1121 	struct ov7251 *ov7251 = to_ov7251(sd);
1122 
1123 	if (sel->target != V4L2_SEL_TGT_CROP)
1124 		return -EINVAL;
1125 
1126 	mutex_lock(&ov7251->lock);
1127 	sel->r = *__ov7251_get_pad_crop(ov7251, cfg, sel->pad,
1128 					sel->which);
1129 	mutex_unlock(&ov7251->lock);
1130 
1131 	return 0;
1132 }
1133 
1134 static int ov7251_s_stream(struct v4l2_subdev *subdev, int enable)
1135 {
1136 	struct ov7251 *ov7251 = to_ov7251(subdev);
1137 	int ret;
1138 
1139 	mutex_lock(&ov7251->lock);
1140 
1141 	if (enable) {
1142 		ret = ov7251_set_register_array(ov7251,
1143 					ov7251->current_mode->data,
1144 					ov7251->current_mode->data_size);
1145 		if (ret < 0) {
1146 			dev_err(ov7251->dev, "could not set mode %dx%d\n",
1147 				ov7251->current_mode->width,
1148 				ov7251->current_mode->height);
1149 			goto exit;
1150 		}
1151 		ret = __v4l2_ctrl_handler_setup(&ov7251->ctrls);
1152 		if (ret < 0) {
1153 			dev_err(ov7251->dev, "could not sync v4l2 controls\n");
1154 			goto exit;
1155 		}
1156 		ret = ov7251_write_reg(ov7251, OV7251_SC_MODE_SELECT,
1157 				       OV7251_SC_MODE_SELECT_STREAMING);
1158 	} else {
1159 		ret = ov7251_write_reg(ov7251, OV7251_SC_MODE_SELECT,
1160 				       OV7251_SC_MODE_SELECT_SW_STANDBY);
1161 	}
1162 
1163 exit:
1164 	mutex_unlock(&ov7251->lock);
1165 
1166 	return ret;
1167 }
1168 
1169 static int ov7251_get_frame_interval(struct v4l2_subdev *subdev,
1170 				     struct v4l2_subdev_frame_interval *fi)
1171 {
1172 	struct ov7251 *ov7251 = to_ov7251(subdev);
1173 
1174 	mutex_lock(&ov7251->lock);
1175 	fi->interval = ov7251->current_mode->timeperframe;
1176 	mutex_unlock(&ov7251->lock);
1177 
1178 	return 0;
1179 }
1180 
1181 static int ov7251_set_frame_interval(struct v4l2_subdev *subdev,
1182 				     struct v4l2_subdev_frame_interval *fi)
1183 {
1184 	struct ov7251 *ov7251 = to_ov7251(subdev);
1185 	const struct ov7251_mode_info *new_mode;
1186 	int ret = 0;
1187 
1188 	mutex_lock(&ov7251->lock);
1189 	new_mode = ov7251_find_mode_by_ival(ov7251, &fi->interval);
1190 
1191 	if (new_mode != ov7251->current_mode) {
1192 		ret = __v4l2_ctrl_s_ctrl_int64(ov7251->pixel_clock,
1193 					       new_mode->pixel_clock);
1194 		if (ret < 0)
1195 			goto exit;
1196 
1197 		ret = __v4l2_ctrl_s_ctrl(ov7251->link_freq,
1198 					 new_mode->link_freq);
1199 		if (ret < 0)
1200 			goto exit;
1201 
1202 		ret = __v4l2_ctrl_modify_range(ov7251->exposure,
1203 					       1, new_mode->exposure_max,
1204 					       1, new_mode->exposure_def);
1205 		if (ret < 0)
1206 			goto exit;
1207 
1208 		ret = __v4l2_ctrl_s_ctrl(ov7251->exposure,
1209 					 new_mode->exposure_def);
1210 		if (ret < 0)
1211 			goto exit;
1212 
1213 		ret = __v4l2_ctrl_s_ctrl(ov7251->gain, 16);
1214 		if (ret < 0)
1215 			goto exit;
1216 
1217 		ov7251->current_mode = new_mode;
1218 	}
1219 
1220 	fi->interval = ov7251->current_mode->timeperframe;
1221 
1222 exit:
1223 	mutex_unlock(&ov7251->lock);
1224 
1225 	return ret;
1226 }
1227 
1228 static const struct v4l2_subdev_core_ops ov7251_core_ops = {
1229 	.s_power = ov7251_s_power,
1230 };
1231 
1232 static const struct v4l2_subdev_video_ops ov7251_video_ops = {
1233 	.s_stream = ov7251_s_stream,
1234 	.g_frame_interval = ov7251_get_frame_interval,
1235 	.s_frame_interval = ov7251_set_frame_interval,
1236 };
1237 
1238 static const struct v4l2_subdev_pad_ops ov7251_subdev_pad_ops = {
1239 	.init_cfg = ov7251_entity_init_cfg,
1240 	.enum_mbus_code = ov7251_enum_mbus_code,
1241 	.enum_frame_size = ov7251_enum_frame_size,
1242 	.enum_frame_interval = ov7251_enum_frame_ival,
1243 	.get_fmt = ov7251_get_format,
1244 	.set_fmt = ov7251_set_format,
1245 	.get_selection = ov7251_get_selection,
1246 };
1247 
1248 static const struct v4l2_subdev_ops ov7251_subdev_ops = {
1249 	.core = &ov7251_core_ops,
1250 	.video = &ov7251_video_ops,
1251 	.pad = &ov7251_subdev_pad_ops,
1252 };
1253 
1254 static int ov7251_probe(struct i2c_client *client)
1255 {
1256 	struct device *dev = &client->dev;
1257 	struct fwnode_handle *endpoint;
1258 	struct ov7251 *ov7251;
1259 	u8 chip_id_high, chip_id_low, chip_rev;
1260 	int ret;
1261 
1262 	ov7251 = devm_kzalloc(dev, sizeof(struct ov7251), GFP_KERNEL);
1263 	if (!ov7251)
1264 		return -ENOMEM;
1265 
1266 	ov7251->i2c_client = client;
1267 	ov7251->dev = dev;
1268 
1269 	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(dev), NULL);
1270 	if (!endpoint) {
1271 		dev_err(dev, "endpoint node not found\n");
1272 		return -EINVAL;
1273 	}
1274 
1275 	ret = v4l2_fwnode_endpoint_parse(endpoint, &ov7251->ep);
1276 	fwnode_handle_put(endpoint);
1277 	if (ret < 0) {
1278 		dev_err(dev, "parsing endpoint node failed\n");
1279 		return ret;
1280 	}
1281 
1282 	if (ov7251->ep.bus_type != V4L2_MBUS_CSI2) {
1283 		dev_err(dev, "invalid bus type (%u), must be CSI2 (%u)\n",
1284 			ov7251->ep.bus_type, V4L2_MBUS_CSI2);
1285 		return -EINVAL;
1286 	}
1287 
1288 	/* get system clock (xclk) */
1289 	ov7251->xclk = devm_clk_get(dev, "xclk");
1290 	if (IS_ERR(ov7251->xclk)) {
1291 		dev_err(dev, "could not get xclk");
1292 		return PTR_ERR(ov7251->xclk);
1293 	}
1294 
1295 	ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
1296 				       &ov7251->xclk_freq);
1297 	if (ret) {
1298 		dev_err(dev, "could not get xclk frequency\n");
1299 		return ret;
1300 	}
1301 
1302 	/* external clock must be 24MHz, allow 1% tolerance */
1303 	if (ov7251->xclk_freq < 23760000 || ov7251->xclk_freq > 24240000) {
1304 		dev_err(dev, "external clock frequency %u is not supported\n",
1305 			ov7251->xclk_freq);
1306 		return -EINVAL;
1307 	}
1308 
1309 	ret = clk_set_rate(ov7251->xclk, ov7251->xclk_freq);
1310 	if (ret) {
1311 		dev_err(dev, "could not set xclk frequency\n");
1312 		return ret;
1313 	}
1314 
1315 	ov7251->io_regulator = devm_regulator_get(dev, "vdddo");
1316 	if (IS_ERR(ov7251->io_regulator)) {
1317 		dev_err(dev, "cannot get io regulator\n");
1318 		return PTR_ERR(ov7251->io_regulator);
1319 	}
1320 
1321 	ov7251->core_regulator = devm_regulator_get(dev, "vddd");
1322 	if (IS_ERR(ov7251->core_regulator)) {
1323 		dev_err(dev, "cannot get core regulator\n");
1324 		return PTR_ERR(ov7251->core_regulator);
1325 	}
1326 
1327 	ov7251->analog_regulator = devm_regulator_get(dev, "vdda");
1328 	if (IS_ERR(ov7251->analog_regulator)) {
1329 		dev_err(dev, "cannot get analog regulator\n");
1330 		return PTR_ERR(ov7251->analog_regulator);
1331 	}
1332 
1333 	ov7251->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_HIGH);
1334 	if (IS_ERR(ov7251->enable_gpio)) {
1335 		dev_err(dev, "cannot get enable gpio\n");
1336 		return PTR_ERR(ov7251->enable_gpio);
1337 	}
1338 
1339 	mutex_init(&ov7251->lock);
1340 
1341 	v4l2_ctrl_handler_init(&ov7251->ctrls, 7);
1342 	ov7251->ctrls.lock = &ov7251->lock;
1343 
1344 	v4l2_ctrl_new_std(&ov7251->ctrls, &ov7251_ctrl_ops,
1345 			  V4L2_CID_HFLIP, 0, 1, 1, 0);
1346 	v4l2_ctrl_new_std(&ov7251->ctrls, &ov7251_ctrl_ops,
1347 			  V4L2_CID_VFLIP, 0, 1, 1, 0);
1348 	ov7251->exposure = v4l2_ctrl_new_std(&ov7251->ctrls, &ov7251_ctrl_ops,
1349 					     V4L2_CID_EXPOSURE, 1, 32, 1, 32);
1350 	ov7251->gain = v4l2_ctrl_new_std(&ov7251->ctrls, &ov7251_ctrl_ops,
1351 					 V4L2_CID_GAIN, 16, 1023, 1, 16);
1352 	v4l2_ctrl_new_std_menu_items(&ov7251->ctrls, &ov7251_ctrl_ops,
1353 				     V4L2_CID_TEST_PATTERN,
1354 				     ARRAY_SIZE(ov7251_test_pattern_menu) - 1,
1355 				     0, 0, ov7251_test_pattern_menu);
1356 	ov7251->pixel_clock = v4l2_ctrl_new_std(&ov7251->ctrls,
1357 						&ov7251_ctrl_ops,
1358 						V4L2_CID_PIXEL_RATE,
1359 						1, INT_MAX, 1, 1);
1360 	ov7251->link_freq = v4l2_ctrl_new_int_menu(&ov7251->ctrls,
1361 						   &ov7251_ctrl_ops,
1362 						   V4L2_CID_LINK_FREQ,
1363 						   ARRAY_SIZE(link_freq) - 1,
1364 						   0, link_freq);
1365 	if (ov7251->link_freq)
1366 		ov7251->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
1367 
1368 	ov7251->sd.ctrl_handler = &ov7251->ctrls;
1369 
1370 	if (ov7251->ctrls.error) {
1371 		dev_err(dev, "%s: control initialization error %d\n",
1372 			__func__, ov7251->ctrls.error);
1373 		ret = ov7251->ctrls.error;
1374 		goto free_ctrl;
1375 	}
1376 
1377 	v4l2_i2c_subdev_init(&ov7251->sd, client, &ov7251_subdev_ops);
1378 	ov7251->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
1379 	ov7251->pad.flags = MEDIA_PAD_FL_SOURCE;
1380 	ov7251->sd.dev = &client->dev;
1381 	ov7251->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
1382 
1383 	ret = media_entity_pads_init(&ov7251->sd.entity, 1, &ov7251->pad);
1384 	if (ret < 0) {
1385 		dev_err(dev, "could not register media entity\n");
1386 		goto free_ctrl;
1387 	}
1388 
1389 	ret = ov7251_s_power(&ov7251->sd, true);
1390 	if (ret < 0) {
1391 		dev_err(dev, "could not power up OV7251\n");
1392 		goto free_entity;
1393 	}
1394 
1395 	ret = ov7251_read_reg(ov7251, OV7251_CHIP_ID_HIGH, &chip_id_high);
1396 	if (ret < 0 || chip_id_high != OV7251_CHIP_ID_HIGH_BYTE) {
1397 		dev_err(dev, "could not read ID high\n");
1398 		ret = -ENODEV;
1399 		goto power_down;
1400 	}
1401 	ret = ov7251_read_reg(ov7251, OV7251_CHIP_ID_LOW, &chip_id_low);
1402 	if (ret < 0 || chip_id_low != OV7251_CHIP_ID_LOW_BYTE) {
1403 		dev_err(dev, "could not read ID low\n");
1404 		ret = -ENODEV;
1405 		goto power_down;
1406 	}
1407 
1408 	ret = ov7251_read_reg(ov7251, OV7251_SC_GP_IO_IN1, &chip_rev);
1409 	if (ret < 0) {
1410 		dev_err(dev, "could not read revision\n");
1411 		ret = -ENODEV;
1412 		goto power_down;
1413 	}
1414 	chip_rev >>= 4;
1415 
1416 	dev_info(dev, "OV7251 revision %x (%s) detected at address 0x%02x\n",
1417 		 chip_rev,
1418 		 chip_rev == 0x4 ? "1A / 1B" :
1419 		 chip_rev == 0x5 ? "1C / 1D" :
1420 		 chip_rev == 0x6 ? "1E" :
1421 		 chip_rev == 0x7 ? "1F" : "unknown",
1422 		 client->addr);
1423 
1424 	ret = ov7251_read_reg(ov7251, OV7251_PRE_ISP_00,
1425 			      &ov7251->pre_isp_00);
1426 	if (ret < 0) {
1427 		dev_err(dev, "could not read test pattern value\n");
1428 		ret = -ENODEV;
1429 		goto power_down;
1430 	}
1431 
1432 	ret = ov7251_read_reg(ov7251, OV7251_TIMING_FORMAT1,
1433 			      &ov7251->timing_format1);
1434 	if (ret < 0) {
1435 		dev_err(dev, "could not read vflip value\n");
1436 		ret = -ENODEV;
1437 		goto power_down;
1438 	}
1439 
1440 	ret = ov7251_read_reg(ov7251, OV7251_TIMING_FORMAT2,
1441 			      &ov7251->timing_format2);
1442 	if (ret < 0) {
1443 		dev_err(dev, "could not read hflip value\n");
1444 		ret = -ENODEV;
1445 		goto power_down;
1446 	}
1447 
1448 	ov7251_s_power(&ov7251->sd, false);
1449 
1450 	ret = v4l2_async_register_subdev(&ov7251->sd);
1451 	if (ret < 0) {
1452 		dev_err(dev, "could not register v4l2 device\n");
1453 		goto free_entity;
1454 	}
1455 
1456 	ov7251_entity_init_cfg(&ov7251->sd, NULL);
1457 
1458 	return 0;
1459 
1460 power_down:
1461 	ov7251_s_power(&ov7251->sd, false);
1462 free_entity:
1463 	media_entity_cleanup(&ov7251->sd.entity);
1464 free_ctrl:
1465 	v4l2_ctrl_handler_free(&ov7251->ctrls);
1466 	mutex_destroy(&ov7251->lock);
1467 
1468 	return ret;
1469 }
1470 
1471 static int ov7251_remove(struct i2c_client *client)
1472 {
1473 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
1474 	struct ov7251 *ov7251 = to_ov7251(sd);
1475 
1476 	v4l2_async_unregister_subdev(&ov7251->sd);
1477 	media_entity_cleanup(&ov7251->sd.entity);
1478 	v4l2_ctrl_handler_free(&ov7251->ctrls);
1479 	mutex_destroy(&ov7251->lock);
1480 
1481 	return 0;
1482 }
1483 
1484 static const struct of_device_id ov7251_of_match[] = {
1485 	{ .compatible = "ovti,ov7251" },
1486 	{ /* sentinel */ }
1487 };
1488 MODULE_DEVICE_TABLE(of, ov7251_of_match);
1489 
1490 static struct i2c_driver ov7251_i2c_driver = {
1491 	.driver = {
1492 		.of_match_table = ov7251_of_match,
1493 		.name  = "ov7251",
1494 	},
1495 	.probe_new  = ov7251_probe,
1496 	.remove = ov7251_remove,
1497 };
1498 
1499 module_i2c_driver(ov7251_i2c_driver);
1500 
1501 MODULE_DESCRIPTION("Omnivision OV7251 Camera Driver");
1502 MODULE_AUTHOR("Todor Tomov <todor.tomov@linaro.org>");
1503 MODULE_LICENSE("GPL v2");
1504