xref: /linux/drivers/media/i2c/ov7670.c (revision ebf68996de0ab250c5d520eb2291ab65643e9a1e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * A V4L2 driver for OmniVision OV7670 cameras.
4  *
5  * Copyright 2006 One Laptop Per Child Association, Inc.  Written
6  * by Jonathan Corbet with substantial inspiration from Mark
7  * McClelland's ovcamchip code.
8  *
9  * Copyright 2006-7 Jonathan Corbet <corbet@lwn.net>
10  */
11 #include <linux/clk.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/i2c.h>
16 #include <linux/delay.h>
17 #include <linux/videodev2.h>
18 #include <linux/gpio.h>
19 #include <linux/gpio/consumer.h>
20 #include <media/v4l2-device.h>
21 #include <media/v4l2-event.h>
22 #include <media/v4l2-ctrls.h>
23 #include <media/v4l2-fwnode.h>
24 #include <media/v4l2-mediabus.h>
25 #include <media/v4l2-image-sizes.h>
26 #include <media/i2c/ov7670.h>
27 
28 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
29 MODULE_DESCRIPTION("A low-level driver for OmniVision ov7670 sensors");
30 MODULE_LICENSE("GPL");
31 
32 static bool debug;
33 module_param(debug, bool, 0644);
34 MODULE_PARM_DESC(debug, "Debug level (0-1)");
35 
36 /*
37  * The 7670 sits on i2c with ID 0x42
38  */
39 #define OV7670_I2C_ADDR 0x42
40 
41 #define PLL_FACTOR	4
42 
43 /* Registers */
44 #define REG_GAIN	0x00	/* Gain lower 8 bits (rest in vref) */
45 #define REG_BLUE	0x01	/* blue gain */
46 #define REG_RED		0x02	/* red gain */
47 #define REG_VREF	0x03	/* Pieces of GAIN, VSTART, VSTOP */
48 #define REG_COM1	0x04	/* Control 1 */
49 #define  COM1_CCIR656	  0x40  /* CCIR656 enable */
50 #define REG_BAVE	0x05	/* U/B Average level */
51 #define REG_GbAVE	0x06	/* Y/Gb Average level */
52 #define REG_AECHH	0x07	/* AEC MS 5 bits */
53 #define REG_RAVE	0x08	/* V/R Average level */
54 #define REG_COM2	0x09	/* Control 2 */
55 #define  COM2_SSLEEP	  0x10	/* Soft sleep mode */
56 #define REG_PID		0x0a	/* Product ID MSB */
57 #define REG_VER		0x0b	/* Product ID LSB */
58 #define REG_COM3	0x0c	/* Control 3 */
59 #define  COM3_SWAP	  0x40	  /* Byte swap */
60 #define  COM3_SCALEEN	  0x08	  /* Enable scaling */
61 #define  COM3_DCWEN	  0x04	  /* Enable downsamp/crop/window */
62 #define REG_COM4	0x0d	/* Control 4 */
63 #define REG_COM5	0x0e	/* All "reserved" */
64 #define REG_COM6	0x0f	/* Control 6 */
65 #define REG_AECH	0x10	/* More bits of AEC value */
66 #define REG_CLKRC	0x11	/* Clocl control */
67 #define   CLK_EXT	  0x40	  /* Use external clock directly */
68 #define   CLK_SCALE	  0x3f	  /* Mask for internal clock scale */
69 #define REG_COM7	0x12	/* Control 7 */
70 #define   COM7_RESET	  0x80	  /* Register reset */
71 #define   COM7_FMT_MASK	  0x38
72 #define   COM7_FMT_VGA	  0x00
73 #define	  COM7_FMT_CIF	  0x20	  /* CIF format */
74 #define   COM7_FMT_QVGA	  0x10	  /* QVGA format */
75 #define   COM7_FMT_QCIF	  0x08	  /* QCIF format */
76 #define	  COM7_RGB	  0x04	  /* bits 0 and 2 - RGB format */
77 #define	  COM7_YUV	  0x00	  /* YUV */
78 #define	  COM7_BAYER	  0x01	  /* Bayer format */
79 #define	  COM7_PBAYER	  0x05	  /* "Processed bayer" */
80 #define REG_COM8	0x13	/* Control 8 */
81 #define   COM8_FASTAEC	  0x80	  /* Enable fast AGC/AEC */
82 #define   COM8_AECSTEP	  0x40	  /* Unlimited AEC step size */
83 #define   COM8_BFILT	  0x20	  /* Band filter enable */
84 #define   COM8_AGC	  0x04	  /* Auto gain enable */
85 #define   COM8_AWB	  0x02	  /* White balance enable */
86 #define   COM8_AEC	  0x01	  /* Auto exposure enable */
87 #define REG_COM9	0x14	/* Control 9  - gain ceiling */
88 #define REG_COM10	0x15	/* Control 10 */
89 #define   COM10_HSYNC	  0x40	  /* HSYNC instead of HREF */
90 #define   COM10_PCLK_HB	  0x20	  /* Suppress PCLK on horiz blank */
91 #define   COM10_HREF_REV  0x08	  /* Reverse HREF */
92 #define   COM10_VS_LEAD	  0x04	  /* VSYNC on clock leading edge */
93 #define   COM10_VS_NEG	  0x02	  /* VSYNC negative */
94 #define   COM10_HS_NEG	  0x01	  /* HSYNC negative */
95 #define REG_HSTART	0x17	/* Horiz start high bits */
96 #define REG_HSTOP	0x18	/* Horiz stop high bits */
97 #define REG_VSTART	0x19	/* Vert start high bits */
98 #define REG_VSTOP	0x1a	/* Vert stop high bits */
99 #define REG_PSHFT	0x1b	/* Pixel delay after HREF */
100 #define REG_MIDH	0x1c	/* Manuf. ID high */
101 #define REG_MIDL	0x1d	/* Manuf. ID low */
102 #define REG_MVFP	0x1e	/* Mirror / vflip */
103 #define   MVFP_MIRROR	  0x20	  /* Mirror image */
104 #define   MVFP_FLIP	  0x10	  /* Vertical flip */
105 
106 #define REG_AEW		0x24	/* AGC upper limit */
107 #define REG_AEB		0x25	/* AGC lower limit */
108 #define REG_VPT		0x26	/* AGC/AEC fast mode op region */
109 #define REG_HSYST	0x30	/* HSYNC rising edge delay */
110 #define REG_HSYEN	0x31	/* HSYNC falling edge delay */
111 #define REG_HREF	0x32	/* HREF pieces */
112 #define REG_TSLB	0x3a	/* lots of stuff */
113 #define   TSLB_YLAST	  0x04	  /* UYVY or VYUY - see com13 */
114 #define REG_COM11	0x3b	/* Control 11 */
115 #define   COM11_NIGHT	  0x80	  /* NIght mode enable */
116 #define   COM11_NMFR	  0x60	  /* Two bit NM frame rate */
117 #define   COM11_HZAUTO	  0x10	  /* Auto detect 50/60 Hz */
118 #define	  COM11_50HZ	  0x08	  /* Manual 50Hz select */
119 #define   COM11_EXP	  0x02
120 #define REG_COM12	0x3c	/* Control 12 */
121 #define   COM12_HREF	  0x80	  /* HREF always */
122 #define REG_COM13	0x3d	/* Control 13 */
123 #define   COM13_GAMMA	  0x80	  /* Gamma enable */
124 #define	  COM13_UVSAT	  0x40	  /* UV saturation auto adjustment */
125 #define   COM13_UVSWAP	  0x01	  /* V before U - w/TSLB */
126 #define REG_COM14	0x3e	/* Control 14 */
127 #define   COM14_DCWEN	  0x10	  /* DCW/PCLK-scale enable */
128 #define REG_EDGE	0x3f	/* Edge enhancement factor */
129 #define REG_COM15	0x40	/* Control 15 */
130 #define   COM15_R10F0	  0x00	  /* Data range 10 to F0 */
131 #define	  COM15_R01FE	  0x80	  /*            01 to FE */
132 #define   COM15_R00FF	  0xc0	  /*            00 to FF */
133 #define   COM15_RGB565	  0x10	  /* RGB565 output */
134 #define   COM15_RGB555	  0x30	  /* RGB555 output */
135 #define REG_COM16	0x41	/* Control 16 */
136 #define   COM16_AWBGAIN   0x08	  /* AWB gain enable */
137 #define REG_COM17	0x42	/* Control 17 */
138 #define   COM17_AECWIN	  0xc0	  /* AEC window - must match COM4 */
139 #define   COM17_CBAR	  0x08	  /* DSP Color bar */
140 
141 /*
142  * This matrix defines how the colors are generated, must be
143  * tweaked to adjust hue and saturation.
144  *
145  * Order: v-red, v-green, v-blue, u-red, u-green, u-blue
146  *
147  * They are nine-bit signed quantities, with the sign bit
148  * stored in 0x58.  Sign for v-red is bit 0, and up from there.
149  */
150 #define	REG_CMATRIX_BASE 0x4f
151 #define   CMATRIX_LEN 6
152 #define REG_CMATRIX_SIGN 0x58
153 
154 
155 #define REG_BRIGHT	0x55	/* Brightness */
156 #define REG_CONTRAS	0x56	/* Contrast control */
157 
158 #define REG_GFIX	0x69	/* Fix gain control */
159 
160 #define REG_DBLV	0x6b	/* PLL control an debugging */
161 #define   DBLV_BYPASS	  0x0a	  /* Bypass PLL */
162 #define   DBLV_X4	  0x4a	  /* clock x4 */
163 #define   DBLV_X6	  0x8a	  /* clock x6 */
164 #define   DBLV_X8	  0xca	  /* clock x8 */
165 
166 #define REG_SCALING_XSC	0x70	/* Test pattern and horizontal scale factor */
167 #define   TEST_PATTTERN_0 0x80
168 #define REG_SCALING_YSC	0x71	/* Test pattern and vertical scale factor */
169 #define   TEST_PATTTERN_1 0x80
170 
171 #define REG_REG76	0x76	/* OV's name */
172 #define   R76_BLKPCOR	  0x80	  /* Black pixel correction enable */
173 #define   R76_WHTPCOR	  0x40	  /* White pixel correction enable */
174 
175 #define REG_RGB444	0x8c	/* RGB 444 control */
176 #define   R444_ENABLE	  0x02	  /* Turn on RGB444, overrides 5x5 */
177 #define   R444_RGBX	  0x01	  /* Empty nibble at end */
178 
179 #define REG_HAECC1	0x9f	/* Hist AEC/AGC control 1 */
180 #define REG_HAECC2	0xa0	/* Hist AEC/AGC control 2 */
181 
182 #define REG_BD50MAX	0xa5	/* 50hz banding step limit */
183 #define REG_HAECC3	0xa6	/* Hist AEC/AGC control 3 */
184 #define REG_HAECC4	0xa7	/* Hist AEC/AGC control 4 */
185 #define REG_HAECC5	0xa8	/* Hist AEC/AGC control 5 */
186 #define REG_HAECC6	0xa9	/* Hist AEC/AGC control 6 */
187 #define REG_HAECC7	0xaa	/* Hist AEC/AGC control 7 */
188 #define REG_BD60MAX	0xab	/* 60hz banding step limit */
189 
190 enum ov7670_model {
191 	MODEL_OV7670 = 0,
192 	MODEL_OV7675,
193 };
194 
195 struct ov7670_win_size {
196 	int	width;
197 	int	height;
198 	unsigned char com7_bit;
199 	int	hstart;		/* Start/stop values for the camera.  Note */
200 	int	hstop;		/* that they do not always make complete */
201 	int	vstart;		/* sense to humans, but evidently the sensor */
202 	int	vstop;		/* will do the right thing... */
203 	struct regval_list *regs; /* Regs to tweak */
204 };
205 
206 struct ov7670_devtype {
207 	/* formats supported for each model */
208 	struct ov7670_win_size *win_sizes;
209 	unsigned int n_win_sizes;
210 	/* callbacks for frame rate control */
211 	int (*set_framerate)(struct v4l2_subdev *, struct v4l2_fract *);
212 	void (*get_framerate)(struct v4l2_subdev *, struct v4l2_fract *);
213 };
214 
215 /*
216  * Information we maintain about a known sensor.
217  */
218 struct ov7670_format_struct;  /* coming later */
219 struct ov7670_info {
220 	struct v4l2_subdev sd;
221 #if defined(CONFIG_MEDIA_CONTROLLER)
222 	struct media_pad pad;
223 #endif
224 	struct v4l2_ctrl_handler hdl;
225 	struct {
226 		/* gain cluster */
227 		struct v4l2_ctrl *auto_gain;
228 		struct v4l2_ctrl *gain;
229 	};
230 	struct {
231 		/* exposure cluster */
232 		struct v4l2_ctrl *auto_exposure;
233 		struct v4l2_ctrl *exposure;
234 	};
235 	struct {
236 		/* saturation/hue cluster */
237 		struct v4l2_ctrl *saturation;
238 		struct v4l2_ctrl *hue;
239 	};
240 	struct v4l2_mbus_framefmt format;
241 	struct ov7670_format_struct *fmt;  /* Current format */
242 	struct ov7670_win_size *wsize;
243 	struct clk *clk;
244 	int on;
245 	struct gpio_desc *resetb_gpio;
246 	struct gpio_desc *pwdn_gpio;
247 	unsigned int mbus_config;	/* Media bus configuration flags */
248 	int min_width;			/* Filter out smaller sizes */
249 	int min_height;			/* Filter out smaller sizes */
250 	int clock_speed;		/* External clock speed (MHz) */
251 	u8 clkrc;			/* Clock divider value */
252 	bool use_smbus;			/* Use smbus I/O instead of I2C */
253 	bool pll_bypass;
254 	bool pclk_hb_disable;
255 	const struct ov7670_devtype *devtype; /* Device specifics */
256 };
257 
258 static inline struct ov7670_info *to_state(struct v4l2_subdev *sd)
259 {
260 	return container_of(sd, struct ov7670_info, sd);
261 }
262 
263 static inline struct v4l2_subdev *to_sd(struct v4l2_ctrl *ctrl)
264 {
265 	return &container_of(ctrl->handler, struct ov7670_info, hdl)->sd;
266 }
267 
268 
269 
270 /*
271  * The default register settings, as obtained from OmniVision.  There
272  * is really no making sense of most of these - lots of "reserved" values
273  * and such.
274  *
275  * These settings give VGA YUYV.
276  */
277 
278 struct regval_list {
279 	unsigned char reg_num;
280 	unsigned char value;
281 };
282 
283 static struct regval_list ov7670_default_regs[] = {
284 	{ REG_COM7, COM7_RESET },
285 /*
286  * Clock scale: 3 = 15fps
287  *              2 = 20fps
288  *              1 = 30fps
289  */
290 	{ REG_CLKRC, 0x1 },	/* OV: clock scale (30 fps) */
291 	{ REG_TSLB,  0x04 },	/* OV */
292 	{ REG_COM7, 0 },	/* VGA */
293 	/*
294 	 * Set the hardware window.  These values from OV don't entirely
295 	 * make sense - hstop is less than hstart.  But they work...
296 	 */
297 	{ REG_HSTART, 0x13 },	{ REG_HSTOP, 0x01 },
298 	{ REG_HREF, 0xb6 },	{ REG_VSTART, 0x02 },
299 	{ REG_VSTOP, 0x7a },	{ REG_VREF, 0x0a },
300 
301 	{ REG_COM3, 0 },	{ REG_COM14, 0 },
302 	/* Mystery scaling numbers */
303 	{ REG_SCALING_XSC, 0x3a },
304 	{ REG_SCALING_YSC, 0x35 },
305 	{ 0x72, 0x11 },		{ 0x73, 0xf0 },
306 	{ 0xa2, 0x02 },		{ REG_COM10, 0x0 },
307 
308 	/* Gamma curve values */
309 	{ 0x7a, 0x20 },		{ 0x7b, 0x10 },
310 	{ 0x7c, 0x1e },		{ 0x7d, 0x35 },
311 	{ 0x7e, 0x5a },		{ 0x7f, 0x69 },
312 	{ 0x80, 0x76 },		{ 0x81, 0x80 },
313 	{ 0x82, 0x88 },		{ 0x83, 0x8f },
314 	{ 0x84, 0x96 },		{ 0x85, 0xa3 },
315 	{ 0x86, 0xaf },		{ 0x87, 0xc4 },
316 	{ 0x88, 0xd7 },		{ 0x89, 0xe8 },
317 
318 	/* AGC and AEC parameters.  Note we start by disabling those features,
319 	   then turn them only after tweaking the values. */
320 	{ REG_COM8, COM8_FASTAEC | COM8_AECSTEP | COM8_BFILT },
321 	{ REG_GAIN, 0 },	{ REG_AECH, 0 },
322 	{ REG_COM4, 0x40 }, /* magic reserved bit */
323 	{ REG_COM9, 0x18 }, /* 4x gain + magic rsvd bit */
324 	{ REG_BD50MAX, 0x05 },	{ REG_BD60MAX, 0x07 },
325 	{ REG_AEW, 0x95 },	{ REG_AEB, 0x33 },
326 	{ REG_VPT, 0xe3 },	{ REG_HAECC1, 0x78 },
327 	{ REG_HAECC2, 0x68 },	{ 0xa1, 0x03 }, /* magic */
328 	{ REG_HAECC3, 0xd8 },	{ REG_HAECC4, 0xd8 },
329 	{ REG_HAECC5, 0xf0 },	{ REG_HAECC6, 0x90 },
330 	{ REG_HAECC7, 0x94 },
331 	{ REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC },
332 
333 	/* Almost all of these are magic "reserved" values.  */
334 	{ REG_COM5, 0x61 },	{ REG_COM6, 0x4b },
335 	{ 0x16, 0x02 },		{ REG_MVFP, 0x07 },
336 	{ 0x21, 0x02 },		{ 0x22, 0x91 },
337 	{ 0x29, 0x07 },		{ 0x33, 0x0b },
338 	{ 0x35, 0x0b },		{ 0x37, 0x1d },
339 	{ 0x38, 0x71 },		{ 0x39, 0x2a },
340 	{ REG_COM12, 0x78 },	{ 0x4d, 0x40 },
341 	{ 0x4e, 0x20 },		{ REG_GFIX, 0 },
342 	{ 0x6b, 0x4a },		{ 0x74, 0x10 },
343 	{ 0x8d, 0x4f },		{ 0x8e, 0 },
344 	{ 0x8f, 0 },		{ 0x90, 0 },
345 	{ 0x91, 0 },		{ 0x96, 0 },
346 	{ 0x9a, 0 },		{ 0xb0, 0x84 },
347 	{ 0xb1, 0x0c },		{ 0xb2, 0x0e },
348 	{ 0xb3, 0x82 },		{ 0xb8, 0x0a },
349 
350 	/* More reserved magic, some of which tweaks white balance */
351 	{ 0x43, 0x0a },		{ 0x44, 0xf0 },
352 	{ 0x45, 0x34 },		{ 0x46, 0x58 },
353 	{ 0x47, 0x28 },		{ 0x48, 0x3a },
354 	{ 0x59, 0x88 },		{ 0x5a, 0x88 },
355 	{ 0x5b, 0x44 },		{ 0x5c, 0x67 },
356 	{ 0x5d, 0x49 },		{ 0x5e, 0x0e },
357 	{ 0x6c, 0x0a },		{ 0x6d, 0x55 },
358 	{ 0x6e, 0x11 },		{ 0x6f, 0x9f }, /* "9e for advance AWB" */
359 	{ 0x6a, 0x40 },		{ REG_BLUE, 0x40 },
360 	{ REG_RED, 0x60 },
361 	{ REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC|COM8_AWB },
362 
363 	/* Matrix coefficients */
364 	{ 0x4f, 0x80 },		{ 0x50, 0x80 },
365 	{ 0x51, 0 },		{ 0x52, 0x22 },
366 	{ 0x53, 0x5e },		{ 0x54, 0x80 },
367 	{ 0x58, 0x9e },
368 
369 	{ REG_COM16, COM16_AWBGAIN },	{ REG_EDGE, 0 },
370 	{ 0x75, 0x05 },		{ 0x76, 0xe1 },
371 	{ 0x4c, 0 },		{ 0x77, 0x01 },
372 	{ REG_COM13, 0xc3 },	{ 0x4b, 0x09 },
373 	{ 0xc9, 0x60 },		{ REG_COM16, 0x38 },
374 	{ 0x56, 0x40 },
375 
376 	{ 0x34, 0x11 },		{ REG_COM11, COM11_EXP|COM11_HZAUTO },
377 	{ 0xa4, 0x88 },		{ 0x96, 0 },
378 	{ 0x97, 0x30 },		{ 0x98, 0x20 },
379 	{ 0x99, 0x30 },		{ 0x9a, 0x84 },
380 	{ 0x9b, 0x29 },		{ 0x9c, 0x03 },
381 	{ 0x9d, 0x4c },		{ 0x9e, 0x3f },
382 	{ 0x78, 0x04 },
383 
384 	/* Extra-weird stuff.  Some sort of multiplexor register */
385 	{ 0x79, 0x01 },		{ 0xc8, 0xf0 },
386 	{ 0x79, 0x0f },		{ 0xc8, 0x00 },
387 	{ 0x79, 0x10 },		{ 0xc8, 0x7e },
388 	{ 0x79, 0x0a },		{ 0xc8, 0x80 },
389 	{ 0x79, 0x0b },		{ 0xc8, 0x01 },
390 	{ 0x79, 0x0c },		{ 0xc8, 0x0f },
391 	{ 0x79, 0x0d },		{ 0xc8, 0x20 },
392 	{ 0x79, 0x09 },		{ 0xc8, 0x80 },
393 	{ 0x79, 0x02 },		{ 0xc8, 0xc0 },
394 	{ 0x79, 0x03 },		{ 0xc8, 0x40 },
395 	{ 0x79, 0x05 },		{ 0xc8, 0x30 },
396 	{ 0x79, 0x26 },
397 
398 	{ 0xff, 0xff },	/* END MARKER */
399 };
400 
401 
402 /*
403  * Here we'll try to encapsulate the changes for just the output
404  * video format.
405  *
406  * RGB656 and YUV422 come from OV; RGB444 is homebrewed.
407  *
408  * IMPORTANT RULE: the first entry must be for COM7, see ov7670_s_fmt for why.
409  */
410 
411 
412 static struct regval_list ov7670_fmt_yuv422[] = {
413 	{ REG_COM7, 0x0 },  /* Selects YUV mode */
414 	{ REG_RGB444, 0 },	/* No RGB444 please */
415 	{ REG_COM1, 0 },	/* CCIR601 */
416 	{ REG_COM15, COM15_R00FF },
417 	{ REG_COM9, 0x48 }, /* 32x gain ceiling; 0x8 is reserved bit */
418 	{ 0x4f, 0x80 },		/* "matrix coefficient 1" */
419 	{ 0x50, 0x80 },		/* "matrix coefficient 2" */
420 	{ 0x51, 0    },		/* vb */
421 	{ 0x52, 0x22 },		/* "matrix coefficient 4" */
422 	{ 0x53, 0x5e },		/* "matrix coefficient 5" */
423 	{ 0x54, 0x80 },		/* "matrix coefficient 6" */
424 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT },
425 	{ 0xff, 0xff },
426 };
427 
428 static struct regval_list ov7670_fmt_rgb565[] = {
429 	{ REG_COM7, COM7_RGB },	/* Selects RGB mode */
430 	{ REG_RGB444, 0 },	/* No RGB444 please */
431 	{ REG_COM1, 0x0 },	/* CCIR601 */
432 	{ REG_COM15, COM15_RGB565 },
433 	{ REG_COM9, 0x38 },	/* 16x gain ceiling; 0x8 is reserved bit */
434 	{ 0x4f, 0xb3 },		/* "matrix coefficient 1" */
435 	{ 0x50, 0xb3 },		/* "matrix coefficient 2" */
436 	{ 0x51, 0    },		/* vb */
437 	{ 0x52, 0x3d },		/* "matrix coefficient 4" */
438 	{ 0x53, 0xa7 },		/* "matrix coefficient 5" */
439 	{ 0x54, 0xe4 },		/* "matrix coefficient 6" */
440 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT },
441 	{ 0xff, 0xff },
442 };
443 
444 static struct regval_list ov7670_fmt_rgb444[] = {
445 	{ REG_COM7, COM7_RGB },	/* Selects RGB mode */
446 	{ REG_RGB444, R444_ENABLE },	/* Enable xxxxrrrr ggggbbbb */
447 	{ REG_COM1, 0x0 },	/* CCIR601 */
448 	{ REG_COM15, COM15_R01FE|COM15_RGB565 }, /* Data range needed? */
449 	{ REG_COM9, 0x38 },	/* 16x gain ceiling; 0x8 is reserved bit */
450 	{ 0x4f, 0xb3 },		/* "matrix coefficient 1" */
451 	{ 0x50, 0xb3 },		/* "matrix coefficient 2" */
452 	{ 0x51, 0    },		/* vb */
453 	{ 0x52, 0x3d },		/* "matrix coefficient 4" */
454 	{ 0x53, 0xa7 },		/* "matrix coefficient 5" */
455 	{ 0x54, 0xe4 },		/* "matrix coefficient 6" */
456 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT|0x2 },  /* Magic rsvd bit */
457 	{ 0xff, 0xff },
458 };
459 
460 static struct regval_list ov7670_fmt_raw[] = {
461 	{ REG_COM7, COM7_BAYER },
462 	{ REG_COM13, 0x08 }, /* No gamma, magic rsvd bit */
463 	{ REG_COM16, 0x3d }, /* Edge enhancement, denoise */
464 	{ REG_REG76, 0xe1 }, /* Pix correction, magic rsvd */
465 	{ 0xff, 0xff },
466 };
467 
468 
469 
470 /*
471  * Low-level register I/O.
472  *
473  * Note that there are two versions of these.  On the XO 1, the
474  * i2c controller only does SMBUS, so that's what we use.  The
475  * ov7670 is not really an SMBUS device, though, so the communication
476  * is not always entirely reliable.
477  */
478 static int ov7670_read_smbus(struct v4l2_subdev *sd, unsigned char reg,
479 		unsigned char *value)
480 {
481 	struct i2c_client *client = v4l2_get_subdevdata(sd);
482 	int ret;
483 
484 	ret = i2c_smbus_read_byte_data(client, reg);
485 	if (ret >= 0) {
486 		*value = (unsigned char)ret;
487 		ret = 0;
488 	}
489 	return ret;
490 }
491 
492 
493 static int ov7670_write_smbus(struct v4l2_subdev *sd, unsigned char reg,
494 		unsigned char value)
495 {
496 	struct i2c_client *client = v4l2_get_subdevdata(sd);
497 	int ret = i2c_smbus_write_byte_data(client, reg, value);
498 
499 	if (reg == REG_COM7 && (value & COM7_RESET))
500 		msleep(5);  /* Wait for reset to run */
501 	return ret;
502 }
503 
504 /*
505  * On most platforms, we'd rather do straight i2c I/O.
506  */
507 static int ov7670_read_i2c(struct v4l2_subdev *sd, unsigned char reg,
508 		unsigned char *value)
509 {
510 	struct i2c_client *client = v4l2_get_subdevdata(sd);
511 	u8 data = reg;
512 	struct i2c_msg msg;
513 	int ret;
514 
515 	/*
516 	 * Send out the register address...
517 	 */
518 	msg.addr = client->addr;
519 	msg.flags = 0;
520 	msg.len = 1;
521 	msg.buf = &data;
522 	ret = i2c_transfer(client->adapter, &msg, 1);
523 	if (ret < 0) {
524 		printk(KERN_ERR "Error %d on register write\n", ret);
525 		return ret;
526 	}
527 	/*
528 	 * ...then read back the result.
529 	 */
530 	msg.flags = I2C_M_RD;
531 	ret = i2c_transfer(client->adapter, &msg, 1);
532 	if (ret >= 0) {
533 		*value = data;
534 		ret = 0;
535 	}
536 	return ret;
537 }
538 
539 
540 static int ov7670_write_i2c(struct v4l2_subdev *sd, unsigned char reg,
541 		unsigned char value)
542 {
543 	struct i2c_client *client = v4l2_get_subdevdata(sd);
544 	struct i2c_msg msg;
545 	unsigned char data[2] = { reg, value };
546 	int ret;
547 
548 	msg.addr = client->addr;
549 	msg.flags = 0;
550 	msg.len = 2;
551 	msg.buf = data;
552 	ret = i2c_transfer(client->adapter, &msg, 1);
553 	if (ret > 0)
554 		ret = 0;
555 	if (reg == REG_COM7 && (value & COM7_RESET))
556 		msleep(5);  /* Wait for reset to run */
557 	return ret;
558 }
559 
560 static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
561 		unsigned char *value)
562 {
563 	struct ov7670_info *info = to_state(sd);
564 	if (info->use_smbus)
565 		return ov7670_read_smbus(sd, reg, value);
566 	else
567 		return ov7670_read_i2c(sd, reg, value);
568 }
569 
570 static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
571 		unsigned char value)
572 {
573 	struct ov7670_info *info = to_state(sd);
574 	if (info->use_smbus)
575 		return ov7670_write_smbus(sd, reg, value);
576 	else
577 		return ov7670_write_i2c(sd, reg, value);
578 }
579 
580 static int ov7670_update_bits(struct v4l2_subdev *sd, unsigned char reg,
581 		unsigned char mask, unsigned char value)
582 {
583 	unsigned char orig;
584 	int ret;
585 
586 	ret = ov7670_read(sd, reg, &orig);
587 	if (ret)
588 		return ret;
589 
590 	return ov7670_write(sd, reg, (orig & ~mask) | (value & mask));
591 }
592 
593 /*
594  * Write a list of register settings; ff/ff stops the process.
595  */
596 static int ov7670_write_array(struct v4l2_subdev *sd, struct regval_list *vals)
597 {
598 	while (vals->reg_num != 0xff || vals->value != 0xff) {
599 		int ret = ov7670_write(sd, vals->reg_num, vals->value);
600 		if (ret < 0)
601 			return ret;
602 		vals++;
603 	}
604 	return 0;
605 }
606 
607 
608 /*
609  * Stuff that knows about the sensor.
610  */
611 static int ov7670_reset(struct v4l2_subdev *sd, u32 val)
612 {
613 	ov7670_write(sd, REG_COM7, COM7_RESET);
614 	msleep(1);
615 	return 0;
616 }
617 
618 
619 static int ov7670_init(struct v4l2_subdev *sd, u32 val)
620 {
621 	return ov7670_write_array(sd, ov7670_default_regs);
622 }
623 
624 static int ov7670_detect(struct v4l2_subdev *sd)
625 {
626 	unsigned char v;
627 	int ret;
628 
629 	ret = ov7670_init(sd, 0);
630 	if (ret < 0)
631 		return ret;
632 	ret = ov7670_read(sd, REG_MIDH, &v);
633 	if (ret < 0)
634 		return ret;
635 	if (v != 0x7f) /* OV manuf. id. */
636 		return -ENODEV;
637 	ret = ov7670_read(sd, REG_MIDL, &v);
638 	if (ret < 0)
639 		return ret;
640 	if (v != 0xa2)
641 		return -ENODEV;
642 	/*
643 	 * OK, we know we have an OmniVision chip...but which one?
644 	 */
645 	ret = ov7670_read(sd, REG_PID, &v);
646 	if (ret < 0)
647 		return ret;
648 	if (v != 0x76)  /* PID + VER = 0x76 / 0x73 */
649 		return -ENODEV;
650 	ret = ov7670_read(sd, REG_VER, &v);
651 	if (ret < 0)
652 		return ret;
653 	if (v != 0x73)  /* PID + VER = 0x76 / 0x73 */
654 		return -ENODEV;
655 	return 0;
656 }
657 
658 
659 /*
660  * Store information about the video data format.  The color matrix
661  * is deeply tied into the format, so keep the relevant values here.
662  * The magic matrix numbers come from OmniVision.
663  */
664 static struct ov7670_format_struct {
665 	u32 mbus_code;
666 	enum v4l2_colorspace colorspace;
667 	struct regval_list *regs;
668 	int cmatrix[CMATRIX_LEN];
669 } ov7670_formats[] = {
670 	{
671 		.mbus_code	= MEDIA_BUS_FMT_YUYV8_2X8,
672 		.colorspace	= V4L2_COLORSPACE_SRGB,
673 		.regs		= ov7670_fmt_yuv422,
674 		.cmatrix	= { 128, -128, 0, -34, -94, 128 },
675 	},
676 	{
677 		.mbus_code	= MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE,
678 		.colorspace	= V4L2_COLORSPACE_SRGB,
679 		.regs		= ov7670_fmt_rgb444,
680 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
681 	},
682 	{
683 		.mbus_code	= MEDIA_BUS_FMT_RGB565_2X8_LE,
684 		.colorspace	= V4L2_COLORSPACE_SRGB,
685 		.regs		= ov7670_fmt_rgb565,
686 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
687 	},
688 	{
689 		.mbus_code	= MEDIA_BUS_FMT_SBGGR8_1X8,
690 		.colorspace	= V4L2_COLORSPACE_SRGB,
691 		.regs		= ov7670_fmt_raw,
692 		.cmatrix	= { 0, 0, 0, 0, 0, 0 },
693 	},
694 };
695 #define N_OV7670_FMTS ARRAY_SIZE(ov7670_formats)
696 
697 
698 /*
699  * Then there is the issue of window sizes.  Try to capture the info here.
700  */
701 
702 /*
703  * QCIF mode is done (by OV) in a very strange way - it actually looks like
704  * VGA with weird scaling options - they do *not* use the canned QCIF mode
705  * which is allegedly provided by the sensor.  So here's the weird register
706  * settings.
707  */
708 static struct regval_list ov7670_qcif_regs[] = {
709 	{ REG_COM3, COM3_SCALEEN|COM3_DCWEN },
710 	{ REG_COM3, COM3_DCWEN },
711 	{ REG_COM14, COM14_DCWEN | 0x01},
712 	{ 0x73, 0xf1 },
713 	{ 0xa2, 0x52 },
714 	{ 0x7b, 0x1c },
715 	{ 0x7c, 0x28 },
716 	{ 0x7d, 0x3c },
717 	{ 0x7f, 0x69 },
718 	{ REG_COM9, 0x38 },
719 	{ 0xa1, 0x0b },
720 	{ 0x74, 0x19 },
721 	{ 0x9a, 0x80 },
722 	{ 0x43, 0x14 },
723 	{ REG_COM13, 0xc0 },
724 	{ 0xff, 0xff },
725 };
726 
727 static struct ov7670_win_size ov7670_win_sizes[] = {
728 	/* VGA */
729 	{
730 		.width		= VGA_WIDTH,
731 		.height		= VGA_HEIGHT,
732 		.com7_bit	= COM7_FMT_VGA,
733 		.hstart		= 158,	/* These values from */
734 		.hstop		=  14,	/* Omnivision */
735 		.vstart		=  10,
736 		.vstop		= 490,
737 		.regs		= NULL,
738 	},
739 	/* CIF */
740 	{
741 		.width		= CIF_WIDTH,
742 		.height		= CIF_HEIGHT,
743 		.com7_bit	= COM7_FMT_CIF,
744 		.hstart		= 170,	/* Empirically determined */
745 		.hstop		=  90,
746 		.vstart		=  14,
747 		.vstop		= 494,
748 		.regs		= NULL,
749 	},
750 	/* QVGA */
751 	{
752 		.width		= QVGA_WIDTH,
753 		.height		= QVGA_HEIGHT,
754 		.com7_bit	= COM7_FMT_QVGA,
755 		.hstart		= 168,	/* Empirically determined */
756 		.hstop		=  24,
757 		.vstart		=  12,
758 		.vstop		= 492,
759 		.regs		= NULL,
760 	},
761 	/* QCIF */
762 	{
763 		.width		= QCIF_WIDTH,
764 		.height		= QCIF_HEIGHT,
765 		.com7_bit	= COM7_FMT_VGA, /* see comment above */
766 		.hstart		= 456,	/* Empirically determined */
767 		.hstop		=  24,
768 		.vstart		=  14,
769 		.vstop		= 494,
770 		.regs		= ov7670_qcif_regs,
771 	}
772 };
773 
774 static struct ov7670_win_size ov7675_win_sizes[] = {
775 	/*
776 	 * Currently, only VGA is supported. Theoretically it could be possible
777 	 * to support CIF, QVGA and QCIF too. Taking values for ov7670 as a
778 	 * base and tweak them empirically could be required.
779 	 */
780 	{
781 		.width		= VGA_WIDTH,
782 		.height		= VGA_HEIGHT,
783 		.com7_bit	= COM7_FMT_VGA,
784 		.hstart		= 158,	/* These values from */
785 		.hstop		=  14,	/* Omnivision */
786 		.vstart		=  14,  /* Empirically determined */
787 		.vstop		= 494,
788 		.regs		= NULL,
789 	}
790 };
791 
792 static void ov7675_get_framerate(struct v4l2_subdev *sd,
793 				 struct v4l2_fract *tpf)
794 {
795 	struct ov7670_info *info = to_state(sd);
796 	u32 clkrc = info->clkrc;
797 	int pll_factor;
798 
799 	if (info->pll_bypass)
800 		pll_factor = 1;
801 	else
802 		pll_factor = PLL_FACTOR;
803 
804 	clkrc++;
805 	if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
806 		clkrc = (clkrc >> 1);
807 
808 	tpf->numerator = 1;
809 	tpf->denominator = (5 * pll_factor * info->clock_speed) /
810 			(4 * clkrc);
811 }
812 
813 static int ov7675_apply_framerate(struct v4l2_subdev *sd)
814 {
815 	struct ov7670_info *info = to_state(sd);
816 	int ret;
817 
818 	ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
819 	if (ret < 0)
820 		return ret;
821 
822 	return ov7670_write(sd, REG_DBLV,
823 			    info->pll_bypass ? DBLV_BYPASS : DBLV_X4);
824 }
825 
826 static int ov7675_set_framerate(struct v4l2_subdev *sd,
827 				 struct v4l2_fract *tpf)
828 {
829 	struct ov7670_info *info = to_state(sd);
830 	u32 clkrc;
831 	int pll_factor;
832 
833 	/*
834 	 * The formula is fps = 5/4*pixclk for YUV/RGB and
835 	 * fps = 5/2*pixclk for RAW.
836 	 *
837 	 * pixclk = clock_speed / (clkrc + 1) * PLLfactor
838 	 *
839 	 */
840 	if (tpf->numerator == 0 || tpf->denominator == 0) {
841 		clkrc = 0;
842 	} else {
843 		pll_factor = info->pll_bypass ? 1 : PLL_FACTOR;
844 		clkrc = (5 * pll_factor * info->clock_speed * tpf->numerator) /
845 			(4 * tpf->denominator);
846 		if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
847 			clkrc = (clkrc << 1);
848 		clkrc--;
849 	}
850 
851 	/*
852 	 * The datasheet claims that clkrc = 0 will divide the input clock by 1
853 	 * but we've checked with an oscilloscope that it divides by 2 instead.
854 	 * So, if clkrc = 0 just bypass the divider.
855 	 */
856 	if (clkrc <= 0)
857 		clkrc = CLK_EXT;
858 	else if (clkrc > CLK_SCALE)
859 		clkrc = CLK_SCALE;
860 	info->clkrc = clkrc;
861 
862 	/* Recalculate frame rate */
863 	ov7675_get_framerate(sd, tpf);
864 
865 	/*
866 	 * If the device is not powered up by the host driver do
867 	 * not apply any changes to H/W at this time. Instead
868 	 * the framerate will be restored right after power-up.
869 	 */
870 	if (info->on)
871 		return ov7675_apply_framerate(sd);
872 
873 	return 0;
874 }
875 
876 static void ov7670_get_framerate_legacy(struct v4l2_subdev *sd,
877 				 struct v4l2_fract *tpf)
878 {
879 	struct ov7670_info *info = to_state(sd);
880 
881 	tpf->numerator = 1;
882 	tpf->denominator = info->clock_speed;
883 	if ((info->clkrc & CLK_EXT) == 0 && (info->clkrc & CLK_SCALE) > 1)
884 		tpf->denominator /= (info->clkrc & CLK_SCALE);
885 }
886 
887 static int ov7670_set_framerate_legacy(struct v4l2_subdev *sd,
888 					struct v4l2_fract *tpf)
889 {
890 	struct ov7670_info *info = to_state(sd);
891 	int div;
892 
893 	if (tpf->numerator == 0 || tpf->denominator == 0)
894 		div = 1;  /* Reset to full rate */
895 	else
896 		div = (tpf->numerator * info->clock_speed) / tpf->denominator;
897 	if (div == 0)
898 		div = 1;
899 	else if (div > CLK_SCALE)
900 		div = CLK_SCALE;
901 	info->clkrc = (info->clkrc & 0x80) | div;
902 	tpf->numerator = 1;
903 	tpf->denominator = info->clock_speed / div;
904 
905 	/*
906 	 * If the device is not powered up by the host driver do
907 	 * not apply any changes to H/W at this time. Instead
908 	 * the framerate will be restored right after power-up.
909 	 */
910 	if (info->on)
911 		return ov7670_write(sd, REG_CLKRC, info->clkrc);
912 
913 	return 0;
914 }
915 
916 /*
917  * Store a set of start/stop values into the camera.
918  */
919 static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop,
920 		int vstart, int vstop)
921 {
922 	int ret;
923 	unsigned char v;
924 /*
925  * Horizontal: 11 bits, top 8 live in hstart and hstop.  Bottom 3 of
926  * hstart are in href[2:0], bottom 3 of hstop in href[5:3].  There is
927  * a mystery "edge offset" value in the top two bits of href.
928  */
929 	ret =  ov7670_write(sd, REG_HSTART, (hstart >> 3) & 0xff);
930 	ret += ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff);
931 	ret += ov7670_read(sd, REG_HREF, &v);
932 	v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7);
933 	msleep(10);
934 	ret += ov7670_write(sd, REG_HREF, v);
935 /*
936  * Vertical: similar arrangement, but only 10 bits.
937  */
938 	ret += ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff);
939 	ret += ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff);
940 	ret += ov7670_read(sd, REG_VREF, &v);
941 	v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3);
942 	msleep(10);
943 	ret += ov7670_write(sd, REG_VREF, v);
944 	return ret;
945 }
946 
947 
948 static int ov7670_enum_mbus_code(struct v4l2_subdev *sd,
949 		struct v4l2_subdev_pad_config *cfg,
950 		struct v4l2_subdev_mbus_code_enum *code)
951 {
952 	if (code->pad || code->index >= N_OV7670_FMTS)
953 		return -EINVAL;
954 
955 	code->code = ov7670_formats[code->index].mbus_code;
956 	return 0;
957 }
958 
959 static int ov7670_try_fmt_internal(struct v4l2_subdev *sd,
960 		struct v4l2_mbus_framefmt *fmt,
961 		struct ov7670_format_struct **ret_fmt,
962 		struct ov7670_win_size **ret_wsize)
963 {
964 	int index, i;
965 	struct ov7670_win_size *wsize;
966 	struct ov7670_info *info = to_state(sd);
967 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
968 	unsigned int win_sizes_limit = n_win_sizes;
969 
970 	for (index = 0; index < N_OV7670_FMTS; index++)
971 		if (ov7670_formats[index].mbus_code == fmt->code)
972 			break;
973 	if (index >= N_OV7670_FMTS) {
974 		/* default to first format */
975 		index = 0;
976 		fmt->code = ov7670_formats[0].mbus_code;
977 	}
978 	if (ret_fmt != NULL)
979 		*ret_fmt = ov7670_formats + index;
980 	/*
981 	 * Fields: the OV devices claim to be progressive.
982 	 */
983 	fmt->field = V4L2_FIELD_NONE;
984 
985 	/*
986 	 * Don't consider values that don't match min_height and min_width
987 	 * constraints.
988 	 */
989 	if (info->min_width || info->min_height)
990 		for (i = 0; i < n_win_sizes; i++) {
991 			wsize = info->devtype->win_sizes + i;
992 
993 			if (wsize->width < info->min_width ||
994 				wsize->height < info->min_height) {
995 				win_sizes_limit = i;
996 				break;
997 			}
998 		}
999 	/*
1000 	 * Round requested image size down to the nearest
1001 	 * we support, but not below the smallest.
1002 	 */
1003 	for (wsize = info->devtype->win_sizes;
1004 	     wsize < info->devtype->win_sizes + win_sizes_limit; wsize++)
1005 		if (fmt->width >= wsize->width && fmt->height >= wsize->height)
1006 			break;
1007 	if (wsize >= info->devtype->win_sizes + win_sizes_limit)
1008 		wsize--;   /* Take the smallest one */
1009 	if (ret_wsize != NULL)
1010 		*ret_wsize = wsize;
1011 	/*
1012 	 * Note the size we'll actually handle.
1013 	 */
1014 	fmt->width = wsize->width;
1015 	fmt->height = wsize->height;
1016 	fmt->colorspace = ov7670_formats[index].colorspace;
1017 
1018 	info->format = *fmt;
1019 
1020 	return 0;
1021 }
1022 
1023 static int ov7670_apply_fmt(struct v4l2_subdev *sd)
1024 {
1025 	struct ov7670_info *info = to_state(sd);
1026 	struct ov7670_win_size *wsize = info->wsize;
1027 	unsigned char com7, com10 = 0;
1028 	int ret;
1029 
1030 	/*
1031 	 * COM7 is a pain in the ass, it doesn't like to be read then
1032 	 * quickly written afterward.  But we have everything we need
1033 	 * to set it absolutely here, as long as the format-specific
1034 	 * register sets list it first.
1035 	 */
1036 	com7 = info->fmt->regs[0].value;
1037 	com7 |= wsize->com7_bit;
1038 	ret = ov7670_write(sd, REG_COM7, com7);
1039 	if (ret)
1040 		return ret;
1041 
1042 	/*
1043 	 * Configure the media bus through COM10 register
1044 	 */
1045 	if (info->mbus_config & V4L2_MBUS_VSYNC_ACTIVE_LOW)
1046 		com10 |= COM10_VS_NEG;
1047 	if (info->mbus_config & V4L2_MBUS_HSYNC_ACTIVE_LOW)
1048 		com10 |= COM10_HREF_REV;
1049 	if (info->pclk_hb_disable)
1050 		com10 |= COM10_PCLK_HB;
1051 	ret = ov7670_write(sd, REG_COM10, com10);
1052 	if (ret)
1053 		return ret;
1054 
1055 	/*
1056 	 * Now write the rest of the array.  Also store start/stops
1057 	 */
1058 	ret = ov7670_write_array(sd, info->fmt->regs + 1);
1059 	if (ret)
1060 		return ret;
1061 
1062 	ret = ov7670_set_hw(sd, wsize->hstart, wsize->hstop, wsize->vstart,
1063 			    wsize->vstop);
1064 	if (ret)
1065 		return ret;
1066 
1067 	if (wsize->regs) {
1068 		ret = ov7670_write_array(sd, wsize->regs);
1069 		if (ret)
1070 			return ret;
1071 	}
1072 
1073 	/*
1074 	 * If we're running RGB565, we must rewrite clkrc after setting
1075 	 * the other parameters or the image looks poor.  If we're *not*
1076 	 * doing RGB565, we must not rewrite clkrc or the image looks
1077 	 * *really* poor.
1078 	 *
1079 	 * (Update) Now that we retain clkrc state, we should be able
1080 	 * to write it unconditionally, and that will make the frame
1081 	 * rate persistent too.
1082 	 */
1083 	ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
1084 	if (ret)
1085 		return ret;
1086 
1087 	return 0;
1088 }
1089 
1090 /*
1091  * Set a format.
1092  */
1093 static int ov7670_set_fmt(struct v4l2_subdev *sd,
1094 		struct v4l2_subdev_pad_config *cfg,
1095 		struct v4l2_subdev_format *format)
1096 {
1097 	struct ov7670_info *info = to_state(sd);
1098 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1099 	struct v4l2_mbus_framefmt *mbus_fmt;
1100 #endif
1101 	int ret;
1102 
1103 	if (format->pad)
1104 		return -EINVAL;
1105 
1106 	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
1107 		ret = ov7670_try_fmt_internal(sd, &format->format, NULL, NULL);
1108 		if (ret)
1109 			return ret;
1110 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1111 		mbus_fmt = v4l2_subdev_get_try_format(sd, cfg, format->pad);
1112 		*mbus_fmt = format->format;
1113 		return 0;
1114 #else
1115 		return -ENOTTY;
1116 #endif
1117 	}
1118 
1119 	ret = ov7670_try_fmt_internal(sd, &format->format, &info->fmt, &info->wsize);
1120 	if (ret)
1121 		return ret;
1122 
1123 	/*
1124 	 * If the device is not powered up by the host driver do
1125 	 * not apply any changes to H/W at this time. Instead
1126 	 * the frame format will be restored right after power-up.
1127 	 */
1128 	if (info->on)
1129 		return ov7670_apply_fmt(sd);
1130 
1131 	return 0;
1132 }
1133 
1134 static int ov7670_get_fmt(struct v4l2_subdev *sd,
1135 			  struct v4l2_subdev_pad_config *cfg,
1136 			  struct v4l2_subdev_format *format)
1137 {
1138 	struct ov7670_info *info = to_state(sd);
1139 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1140 	struct v4l2_mbus_framefmt *mbus_fmt;
1141 #endif
1142 
1143 	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
1144 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1145 		mbus_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
1146 		format->format = *mbus_fmt;
1147 		return 0;
1148 #else
1149 		return -ENOTTY;
1150 #endif
1151 	} else {
1152 		format->format = info->format;
1153 	}
1154 
1155 	return 0;
1156 }
1157 
1158 /*
1159  * Implement G/S_PARM.  There is a "high quality" mode we could try
1160  * to do someday; for now, we just do the frame rate tweak.
1161  */
1162 static int ov7670_g_frame_interval(struct v4l2_subdev *sd,
1163 				   struct v4l2_subdev_frame_interval *ival)
1164 {
1165 	struct ov7670_info *info = to_state(sd);
1166 
1167 
1168 	info->devtype->get_framerate(sd, &ival->interval);
1169 
1170 	return 0;
1171 }
1172 
1173 static int ov7670_s_frame_interval(struct v4l2_subdev *sd,
1174 				   struct v4l2_subdev_frame_interval *ival)
1175 {
1176 	struct v4l2_fract *tpf = &ival->interval;
1177 	struct ov7670_info *info = to_state(sd);
1178 
1179 
1180 	return info->devtype->set_framerate(sd, tpf);
1181 }
1182 
1183 
1184 /*
1185  * Frame intervals.  Since frame rates are controlled with the clock
1186  * divider, we can only do 30/n for integer n values.  So no continuous
1187  * or stepwise options.  Here we just pick a handful of logical values.
1188  */
1189 
1190 static int ov7670_frame_rates[] = { 30, 15, 10, 5, 1 };
1191 
1192 static int ov7670_enum_frame_interval(struct v4l2_subdev *sd,
1193 				      struct v4l2_subdev_pad_config *cfg,
1194 				      struct v4l2_subdev_frame_interval_enum *fie)
1195 {
1196 	struct ov7670_info *info = to_state(sd);
1197 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
1198 	int i;
1199 
1200 	if (fie->pad)
1201 		return -EINVAL;
1202 	if (fie->index >= ARRAY_SIZE(ov7670_frame_rates))
1203 		return -EINVAL;
1204 
1205 	/*
1206 	 * Check if the width/height is valid.
1207 	 *
1208 	 * If a minimum width/height was requested, filter out the capture
1209 	 * windows that fall outside that.
1210 	 */
1211 	for (i = 0; i < n_win_sizes; i++) {
1212 		struct ov7670_win_size *win = &info->devtype->win_sizes[i];
1213 
1214 		if (info->min_width && win->width < info->min_width)
1215 			continue;
1216 		if (info->min_height && win->height < info->min_height)
1217 			continue;
1218 		if (fie->width == win->width && fie->height == win->height)
1219 			break;
1220 	}
1221 	if (i == n_win_sizes)
1222 		return -EINVAL;
1223 	fie->interval.numerator = 1;
1224 	fie->interval.denominator = ov7670_frame_rates[fie->index];
1225 	return 0;
1226 }
1227 
1228 /*
1229  * Frame size enumeration
1230  */
1231 static int ov7670_enum_frame_size(struct v4l2_subdev *sd,
1232 				  struct v4l2_subdev_pad_config *cfg,
1233 				  struct v4l2_subdev_frame_size_enum *fse)
1234 {
1235 	struct ov7670_info *info = to_state(sd);
1236 	int i;
1237 	int num_valid = -1;
1238 	__u32 index = fse->index;
1239 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
1240 
1241 	if (fse->pad)
1242 		return -EINVAL;
1243 
1244 	/*
1245 	 * If a minimum width/height was requested, filter out the capture
1246 	 * windows that fall outside that.
1247 	 */
1248 	for (i = 0; i < n_win_sizes; i++) {
1249 		struct ov7670_win_size *win = &info->devtype->win_sizes[i];
1250 		if (info->min_width && win->width < info->min_width)
1251 			continue;
1252 		if (info->min_height && win->height < info->min_height)
1253 			continue;
1254 		if (index == ++num_valid) {
1255 			fse->min_width = fse->max_width = win->width;
1256 			fse->min_height = fse->max_height = win->height;
1257 			return 0;
1258 		}
1259 	}
1260 
1261 	return -EINVAL;
1262 }
1263 
1264 /*
1265  * Code for dealing with controls.
1266  */
1267 
1268 static int ov7670_store_cmatrix(struct v4l2_subdev *sd,
1269 		int matrix[CMATRIX_LEN])
1270 {
1271 	int i, ret;
1272 	unsigned char signbits = 0;
1273 
1274 	/*
1275 	 * Weird crap seems to exist in the upper part of
1276 	 * the sign bits register, so let's preserve it.
1277 	 */
1278 	ret = ov7670_read(sd, REG_CMATRIX_SIGN, &signbits);
1279 	signbits &= 0xc0;
1280 
1281 	for (i = 0; i < CMATRIX_LEN; i++) {
1282 		unsigned char raw;
1283 
1284 		if (matrix[i] < 0) {
1285 			signbits |= (1 << i);
1286 			if (matrix[i] < -255)
1287 				raw = 0xff;
1288 			else
1289 				raw = (-1 * matrix[i]) & 0xff;
1290 		}
1291 		else {
1292 			if (matrix[i] > 255)
1293 				raw = 0xff;
1294 			else
1295 				raw = matrix[i] & 0xff;
1296 		}
1297 		ret += ov7670_write(sd, REG_CMATRIX_BASE + i, raw);
1298 	}
1299 	ret += ov7670_write(sd, REG_CMATRIX_SIGN, signbits);
1300 	return ret;
1301 }
1302 
1303 
1304 /*
1305  * Hue also requires messing with the color matrix.  It also requires
1306  * trig functions, which tend not to be well supported in the kernel.
1307  * So here is a simple table of sine values, 0-90 degrees, in steps
1308  * of five degrees.  Values are multiplied by 1000.
1309  *
1310  * The following naive approximate trig functions require an argument
1311  * carefully limited to -180 <= theta <= 180.
1312  */
1313 #define SIN_STEP 5
1314 static const int ov7670_sin_table[] = {
1315 	   0,	 87,   173,   258,   342,   422,
1316 	 499,	573,   642,   707,   766,   819,
1317 	 866,	906,   939,   965,   984,   996,
1318 	1000
1319 };
1320 
1321 static int ov7670_sine(int theta)
1322 {
1323 	int chs = 1;
1324 	int sine;
1325 
1326 	if (theta < 0) {
1327 		theta = -theta;
1328 		chs = -1;
1329 	}
1330 	if (theta <= 90)
1331 		sine = ov7670_sin_table[theta/SIN_STEP];
1332 	else {
1333 		theta -= 90;
1334 		sine = 1000 - ov7670_sin_table[theta/SIN_STEP];
1335 	}
1336 	return sine*chs;
1337 }
1338 
1339 static int ov7670_cosine(int theta)
1340 {
1341 	theta = 90 - theta;
1342 	if (theta > 180)
1343 		theta -= 360;
1344 	else if (theta < -180)
1345 		theta += 360;
1346 	return ov7670_sine(theta);
1347 }
1348 
1349 
1350 
1351 
1352 static void ov7670_calc_cmatrix(struct ov7670_info *info,
1353 		int matrix[CMATRIX_LEN], int sat, int hue)
1354 {
1355 	int i;
1356 	/*
1357 	 * Apply the current saturation setting first.
1358 	 */
1359 	for (i = 0; i < CMATRIX_LEN; i++)
1360 		matrix[i] = (info->fmt->cmatrix[i] * sat) >> 7;
1361 	/*
1362 	 * Then, if need be, rotate the hue value.
1363 	 */
1364 	if (hue != 0) {
1365 		int sinth, costh, tmpmatrix[CMATRIX_LEN];
1366 
1367 		memcpy(tmpmatrix, matrix, CMATRIX_LEN*sizeof(int));
1368 		sinth = ov7670_sine(hue);
1369 		costh = ov7670_cosine(hue);
1370 
1371 		matrix[0] = (matrix[3]*sinth + matrix[0]*costh)/1000;
1372 		matrix[1] = (matrix[4]*sinth + matrix[1]*costh)/1000;
1373 		matrix[2] = (matrix[5]*sinth + matrix[2]*costh)/1000;
1374 		matrix[3] = (matrix[3]*costh - matrix[0]*sinth)/1000;
1375 		matrix[4] = (matrix[4]*costh - matrix[1]*sinth)/1000;
1376 		matrix[5] = (matrix[5]*costh - matrix[2]*sinth)/1000;
1377 	}
1378 }
1379 
1380 
1381 
1382 static int ov7670_s_sat_hue(struct v4l2_subdev *sd, int sat, int hue)
1383 {
1384 	struct ov7670_info *info = to_state(sd);
1385 	int matrix[CMATRIX_LEN];
1386 	int ret;
1387 
1388 	ov7670_calc_cmatrix(info, matrix, sat, hue);
1389 	ret = ov7670_store_cmatrix(sd, matrix);
1390 	return ret;
1391 }
1392 
1393 
1394 /*
1395  * Some weird registers seem to store values in a sign/magnitude format!
1396  */
1397 
1398 static unsigned char ov7670_abs_to_sm(unsigned char v)
1399 {
1400 	if (v > 127)
1401 		return v & 0x7f;
1402 	return (128 - v) | 0x80;
1403 }
1404 
1405 static int ov7670_s_brightness(struct v4l2_subdev *sd, int value)
1406 {
1407 	unsigned char com8 = 0, v;
1408 	int ret;
1409 
1410 	ov7670_read(sd, REG_COM8, &com8);
1411 	com8 &= ~COM8_AEC;
1412 	ov7670_write(sd, REG_COM8, com8);
1413 	v = ov7670_abs_to_sm(value);
1414 	ret = ov7670_write(sd, REG_BRIGHT, v);
1415 	return ret;
1416 }
1417 
1418 static int ov7670_s_contrast(struct v4l2_subdev *sd, int value)
1419 {
1420 	return ov7670_write(sd, REG_CONTRAS, (unsigned char) value);
1421 }
1422 
1423 static int ov7670_s_hflip(struct v4l2_subdev *sd, int value)
1424 {
1425 	unsigned char v = 0;
1426 	int ret;
1427 
1428 	ret = ov7670_read(sd, REG_MVFP, &v);
1429 	if (value)
1430 		v |= MVFP_MIRROR;
1431 	else
1432 		v &= ~MVFP_MIRROR;
1433 	msleep(10);  /* FIXME */
1434 	ret += ov7670_write(sd, REG_MVFP, v);
1435 	return ret;
1436 }
1437 
1438 static int ov7670_s_vflip(struct v4l2_subdev *sd, int value)
1439 {
1440 	unsigned char v = 0;
1441 	int ret;
1442 
1443 	ret = ov7670_read(sd, REG_MVFP, &v);
1444 	if (value)
1445 		v |= MVFP_FLIP;
1446 	else
1447 		v &= ~MVFP_FLIP;
1448 	msleep(10);  /* FIXME */
1449 	ret += ov7670_write(sd, REG_MVFP, v);
1450 	return ret;
1451 }
1452 
1453 /*
1454  * GAIN is split between REG_GAIN and REG_VREF[7:6].  If one believes
1455  * the data sheet, the VREF parts should be the most significant, but
1456  * experience shows otherwise.  There seems to be little value in
1457  * messing with the VREF bits, so we leave them alone.
1458  */
1459 static int ov7670_g_gain(struct v4l2_subdev *sd, __s32 *value)
1460 {
1461 	int ret;
1462 	unsigned char gain;
1463 
1464 	ret = ov7670_read(sd, REG_GAIN, &gain);
1465 	*value = gain;
1466 	return ret;
1467 }
1468 
1469 static int ov7670_s_gain(struct v4l2_subdev *sd, int value)
1470 {
1471 	int ret;
1472 	unsigned char com8;
1473 
1474 	ret = ov7670_write(sd, REG_GAIN, value & 0xff);
1475 	/* Have to turn off AGC as well */
1476 	if (ret == 0) {
1477 		ret = ov7670_read(sd, REG_COM8, &com8);
1478 		ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
1479 	}
1480 	return ret;
1481 }
1482 
1483 /*
1484  * Tweak autogain.
1485  */
1486 static int ov7670_s_autogain(struct v4l2_subdev *sd, int value)
1487 {
1488 	int ret;
1489 	unsigned char com8;
1490 
1491 	ret = ov7670_read(sd, REG_COM8, &com8);
1492 	if (ret == 0) {
1493 		if (value)
1494 			com8 |= COM8_AGC;
1495 		else
1496 			com8 &= ~COM8_AGC;
1497 		ret = ov7670_write(sd, REG_COM8, com8);
1498 	}
1499 	return ret;
1500 }
1501 
1502 static int ov7670_s_exp(struct v4l2_subdev *sd, int value)
1503 {
1504 	int ret;
1505 	unsigned char com1, com8, aech, aechh;
1506 
1507 	ret = ov7670_read(sd, REG_COM1, &com1) +
1508 		ov7670_read(sd, REG_COM8, &com8) +
1509 		ov7670_read(sd, REG_AECHH, &aechh);
1510 	if (ret)
1511 		return ret;
1512 
1513 	com1 = (com1 & 0xfc) | (value & 0x03);
1514 	aech = (value >> 2) & 0xff;
1515 	aechh = (aechh & 0xc0) | ((value >> 10) & 0x3f);
1516 	ret = ov7670_write(sd, REG_COM1, com1) +
1517 		ov7670_write(sd, REG_AECH, aech) +
1518 		ov7670_write(sd, REG_AECHH, aechh);
1519 	/* Have to turn off AEC as well */
1520 	if (ret == 0)
1521 		ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AEC);
1522 	return ret;
1523 }
1524 
1525 /*
1526  * Tweak autoexposure.
1527  */
1528 static int ov7670_s_autoexp(struct v4l2_subdev *sd,
1529 		enum v4l2_exposure_auto_type value)
1530 {
1531 	int ret;
1532 	unsigned char com8;
1533 
1534 	ret = ov7670_read(sd, REG_COM8, &com8);
1535 	if (ret == 0) {
1536 		if (value == V4L2_EXPOSURE_AUTO)
1537 			com8 |= COM8_AEC;
1538 		else
1539 			com8 &= ~COM8_AEC;
1540 		ret = ov7670_write(sd, REG_COM8, com8);
1541 	}
1542 	return ret;
1543 }
1544 
1545 static const char * const ov7670_test_pattern_menu[] = {
1546 	"No test output",
1547 	"Shifting \"1\"",
1548 	"8-bar color bar",
1549 	"Fade to gray color bar",
1550 };
1551 
1552 static int ov7670_s_test_pattern(struct v4l2_subdev *sd, int value)
1553 {
1554 	int ret;
1555 
1556 	ret = ov7670_update_bits(sd, REG_SCALING_XSC, TEST_PATTTERN_0,
1557 				value & BIT(0) ? TEST_PATTTERN_0 : 0);
1558 	if (ret)
1559 		return ret;
1560 
1561 	return ov7670_update_bits(sd, REG_SCALING_YSC, TEST_PATTTERN_1,
1562 				value & BIT(1) ? TEST_PATTTERN_1 : 0);
1563 }
1564 
1565 static int ov7670_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
1566 {
1567 	struct v4l2_subdev *sd = to_sd(ctrl);
1568 	struct ov7670_info *info = to_state(sd);
1569 
1570 	switch (ctrl->id) {
1571 	case V4L2_CID_AUTOGAIN:
1572 		return ov7670_g_gain(sd, &info->gain->val);
1573 	}
1574 	return -EINVAL;
1575 }
1576 
1577 static int ov7670_s_ctrl(struct v4l2_ctrl *ctrl)
1578 {
1579 	struct v4l2_subdev *sd = to_sd(ctrl);
1580 	struct ov7670_info *info = to_state(sd);
1581 
1582 	switch (ctrl->id) {
1583 	case V4L2_CID_BRIGHTNESS:
1584 		return ov7670_s_brightness(sd, ctrl->val);
1585 	case V4L2_CID_CONTRAST:
1586 		return ov7670_s_contrast(sd, ctrl->val);
1587 	case V4L2_CID_SATURATION:
1588 		return ov7670_s_sat_hue(sd,
1589 				info->saturation->val, info->hue->val);
1590 	case V4L2_CID_VFLIP:
1591 		return ov7670_s_vflip(sd, ctrl->val);
1592 	case V4L2_CID_HFLIP:
1593 		return ov7670_s_hflip(sd, ctrl->val);
1594 	case V4L2_CID_AUTOGAIN:
1595 		/* Only set manual gain if auto gain is not explicitly
1596 		   turned on. */
1597 		if (!ctrl->val) {
1598 			/* ov7670_s_gain turns off auto gain */
1599 			return ov7670_s_gain(sd, info->gain->val);
1600 		}
1601 		return ov7670_s_autogain(sd, ctrl->val);
1602 	case V4L2_CID_EXPOSURE_AUTO:
1603 		/* Only set manual exposure if auto exposure is not explicitly
1604 		   turned on. */
1605 		if (ctrl->val == V4L2_EXPOSURE_MANUAL) {
1606 			/* ov7670_s_exp turns off auto exposure */
1607 			return ov7670_s_exp(sd, info->exposure->val);
1608 		}
1609 		return ov7670_s_autoexp(sd, ctrl->val);
1610 	case V4L2_CID_TEST_PATTERN:
1611 		return ov7670_s_test_pattern(sd, ctrl->val);
1612 	}
1613 	return -EINVAL;
1614 }
1615 
1616 static const struct v4l2_ctrl_ops ov7670_ctrl_ops = {
1617 	.s_ctrl = ov7670_s_ctrl,
1618 	.g_volatile_ctrl = ov7670_g_volatile_ctrl,
1619 };
1620 
1621 #ifdef CONFIG_VIDEO_ADV_DEBUG
1622 static int ov7670_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
1623 {
1624 	unsigned char val = 0;
1625 	int ret;
1626 
1627 	ret = ov7670_read(sd, reg->reg & 0xff, &val);
1628 	reg->val = val;
1629 	reg->size = 1;
1630 	return ret;
1631 }
1632 
1633 static int ov7670_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
1634 {
1635 	ov7670_write(sd, reg->reg & 0xff, reg->val & 0xff);
1636 	return 0;
1637 }
1638 #endif
1639 
1640 static void ov7670_power_on(struct v4l2_subdev *sd)
1641 {
1642 	struct ov7670_info *info = to_state(sd);
1643 
1644 	if (info->on)
1645 		return;
1646 
1647 	clk_prepare_enable(info->clk);
1648 
1649 	if (info->pwdn_gpio)
1650 		gpiod_set_value(info->pwdn_gpio, 0);
1651 	if (info->resetb_gpio) {
1652 		gpiod_set_value(info->resetb_gpio, 1);
1653 		usleep_range(500, 1000);
1654 		gpiod_set_value(info->resetb_gpio, 0);
1655 	}
1656 	if (info->pwdn_gpio || info->resetb_gpio || info->clk)
1657 		usleep_range(3000, 5000);
1658 
1659 	info->on = true;
1660 }
1661 
1662 static void ov7670_power_off(struct v4l2_subdev *sd)
1663 {
1664 	struct ov7670_info *info = to_state(sd);
1665 
1666 	if (!info->on)
1667 		return;
1668 
1669 	clk_disable_unprepare(info->clk);
1670 
1671 	if (info->pwdn_gpio)
1672 		gpiod_set_value(info->pwdn_gpio, 1);
1673 
1674 	info->on = false;
1675 }
1676 
1677 static int ov7670_s_power(struct v4l2_subdev *sd, int on)
1678 {
1679 	struct ov7670_info *info = to_state(sd);
1680 
1681 	if (info->on == on)
1682 		return 0;
1683 
1684 	if (on) {
1685 		ov7670_power_on (sd);
1686 		ov7670_init(sd, 0);
1687 		ov7670_apply_fmt(sd);
1688 		ov7675_apply_framerate(sd);
1689 		v4l2_ctrl_handler_setup(&info->hdl);
1690 	} else {
1691 		ov7670_power_off (sd);
1692 	}
1693 
1694 	return 0;
1695 }
1696 
1697 static void ov7670_get_default_format(struct v4l2_subdev *sd,
1698 				      struct v4l2_mbus_framefmt *format)
1699 {
1700 	struct ov7670_info *info = to_state(sd);
1701 
1702 	format->width = info->devtype->win_sizes[0].width;
1703 	format->height = info->devtype->win_sizes[0].height;
1704 	format->colorspace = info->fmt->colorspace;
1705 	format->code = info->fmt->mbus_code;
1706 	format->field = V4L2_FIELD_NONE;
1707 }
1708 
1709 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1710 static int ov7670_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
1711 {
1712 	struct v4l2_mbus_framefmt *format =
1713 				v4l2_subdev_get_try_format(sd, fh->pad, 0);
1714 
1715 	ov7670_get_default_format(sd, format);
1716 
1717 	return 0;
1718 }
1719 #endif
1720 
1721 /* ----------------------------------------------------------------------- */
1722 
1723 static const struct v4l2_subdev_core_ops ov7670_core_ops = {
1724 	.reset = ov7670_reset,
1725 	.init = ov7670_init,
1726 	.s_power = ov7670_s_power,
1727 	.log_status = v4l2_ctrl_subdev_log_status,
1728 	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
1729 	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
1730 #ifdef CONFIG_VIDEO_ADV_DEBUG
1731 	.g_register = ov7670_g_register,
1732 	.s_register = ov7670_s_register,
1733 #endif
1734 };
1735 
1736 static const struct v4l2_subdev_video_ops ov7670_video_ops = {
1737 	.s_frame_interval = ov7670_s_frame_interval,
1738 	.g_frame_interval = ov7670_g_frame_interval,
1739 };
1740 
1741 static const struct v4l2_subdev_pad_ops ov7670_pad_ops = {
1742 	.enum_frame_interval = ov7670_enum_frame_interval,
1743 	.enum_frame_size = ov7670_enum_frame_size,
1744 	.enum_mbus_code = ov7670_enum_mbus_code,
1745 	.get_fmt = ov7670_get_fmt,
1746 	.set_fmt = ov7670_set_fmt,
1747 };
1748 
1749 static const struct v4l2_subdev_ops ov7670_ops = {
1750 	.core = &ov7670_core_ops,
1751 	.video = &ov7670_video_ops,
1752 	.pad = &ov7670_pad_ops,
1753 };
1754 
1755 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1756 static const struct v4l2_subdev_internal_ops ov7670_subdev_internal_ops = {
1757 	.open = ov7670_open,
1758 };
1759 #endif
1760 
1761 /* ----------------------------------------------------------------------- */
1762 
1763 static const struct ov7670_devtype ov7670_devdata[] = {
1764 	[MODEL_OV7670] = {
1765 		.win_sizes = ov7670_win_sizes,
1766 		.n_win_sizes = ARRAY_SIZE(ov7670_win_sizes),
1767 		.set_framerate = ov7670_set_framerate_legacy,
1768 		.get_framerate = ov7670_get_framerate_legacy,
1769 	},
1770 	[MODEL_OV7675] = {
1771 		.win_sizes = ov7675_win_sizes,
1772 		.n_win_sizes = ARRAY_SIZE(ov7675_win_sizes),
1773 		.set_framerate = ov7675_set_framerate,
1774 		.get_framerate = ov7675_get_framerate,
1775 	},
1776 };
1777 
1778 static int ov7670_init_gpio(struct i2c_client *client, struct ov7670_info *info)
1779 {
1780 	info->pwdn_gpio = devm_gpiod_get_optional(&client->dev, "powerdown",
1781 			GPIOD_OUT_LOW);
1782 	if (IS_ERR(info->pwdn_gpio)) {
1783 		dev_info(&client->dev, "can't get %s GPIO\n", "powerdown");
1784 		return PTR_ERR(info->pwdn_gpio);
1785 	}
1786 
1787 	info->resetb_gpio = devm_gpiod_get_optional(&client->dev, "reset",
1788 			GPIOD_OUT_LOW);
1789 	if (IS_ERR(info->resetb_gpio)) {
1790 		dev_info(&client->dev, "can't get %s GPIO\n", "reset");
1791 		return PTR_ERR(info->resetb_gpio);
1792 	}
1793 
1794 	usleep_range(3000, 5000);
1795 
1796 	return 0;
1797 }
1798 
1799 /*
1800  * ov7670_parse_dt() - Parse device tree to collect mbus configuration
1801  *			properties
1802  */
1803 static int ov7670_parse_dt(struct device *dev,
1804 			   struct ov7670_info *info)
1805 {
1806 	struct fwnode_handle *fwnode = dev_fwnode(dev);
1807 	struct v4l2_fwnode_endpoint bus_cfg = { .bus_type = 0 };
1808 	struct fwnode_handle *ep;
1809 	int ret;
1810 
1811 	if (!fwnode)
1812 		return -EINVAL;
1813 
1814 	info->pclk_hb_disable = false;
1815 	if (fwnode_property_present(fwnode, "ov7670,pclk-hb-disable"))
1816 		info->pclk_hb_disable = true;
1817 
1818 	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
1819 	if (!ep)
1820 		return -EINVAL;
1821 
1822 	ret = v4l2_fwnode_endpoint_parse(ep, &bus_cfg);
1823 	fwnode_handle_put(ep);
1824 	if (ret)
1825 		return ret;
1826 
1827 	if (bus_cfg.bus_type != V4L2_MBUS_PARALLEL) {
1828 		dev_err(dev, "Unsupported media bus type\n");
1829 		return ret;
1830 	}
1831 	info->mbus_config = bus_cfg.bus.parallel.flags;
1832 
1833 	return 0;
1834 }
1835 
1836 static int ov7670_probe(struct i2c_client *client,
1837 			const struct i2c_device_id *id)
1838 {
1839 	struct v4l2_fract tpf;
1840 	struct v4l2_subdev *sd;
1841 	struct ov7670_info *info;
1842 	int ret;
1843 
1844 	info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
1845 	if (info == NULL)
1846 		return -ENOMEM;
1847 	sd = &info->sd;
1848 	v4l2_i2c_subdev_init(sd, client, &ov7670_ops);
1849 
1850 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1851 	sd->internal_ops = &ov7670_subdev_internal_ops;
1852 	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
1853 #endif
1854 
1855 	info->clock_speed = 30; /* default: a guess */
1856 
1857 	if (dev_fwnode(&client->dev)) {
1858 		ret = ov7670_parse_dt(&client->dev, info);
1859 		if (ret)
1860 			return ret;
1861 
1862 	} else if (client->dev.platform_data) {
1863 		struct ov7670_config *config = client->dev.platform_data;
1864 
1865 		/*
1866 		 * Must apply configuration before initializing device, because it
1867 		 * selects I/O method.
1868 		 */
1869 		info->min_width = config->min_width;
1870 		info->min_height = config->min_height;
1871 		info->use_smbus = config->use_smbus;
1872 
1873 		if (config->clock_speed)
1874 			info->clock_speed = config->clock_speed;
1875 
1876 		if (config->pll_bypass)
1877 			info->pll_bypass = true;
1878 
1879 		if (config->pclk_hb_disable)
1880 			info->pclk_hb_disable = true;
1881 	}
1882 
1883 	info->clk = devm_clk_get(&client->dev, "xclk"); /* optional */
1884 	if (IS_ERR(info->clk)) {
1885 		ret = PTR_ERR(info->clk);
1886 		if (ret == -ENOENT)
1887 			info->clk = NULL;
1888 		else
1889 			return ret;
1890 	}
1891 
1892 	ret = ov7670_init_gpio(client, info);
1893 	if (ret)
1894 		return ret;
1895 
1896 	ov7670_power_on(sd);
1897 
1898 	if (info->clk) {
1899 		info->clock_speed = clk_get_rate(info->clk) / 1000000;
1900 		if (info->clock_speed < 10 || info->clock_speed > 48) {
1901 			ret = -EINVAL;
1902 			goto power_off;
1903 		}
1904 	}
1905 
1906 	/* Make sure it's an ov7670 */
1907 	ret = ov7670_detect(sd);
1908 	if (ret) {
1909 		v4l_dbg(1, debug, client,
1910 			"chip found @ 0x%x (%s) is not an ov7670 chip.\n",
1911 			client->addr << 1, client->adapter->name);
1912 		goto power_off;
1913 	}
1914 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
1915 			client->addr << 1, client->adapter->name);
1916 
1917 	info->devtype = &ov7670_devdata[id->driver_data];
1918 	info->fmt = &ov7670_formats[0];
1919 	info->wsize = &info->devtype->win_sizes[0];
1920 
1921 	ov7670_get_default_format(sd, &info->format);
1922 
1923 	info->clkrc = 0;
1924 
1925 	/* Set default frame rate to 30 fps */
1926 	tpf.numerator = 1;
1927 	tpf.denominator = 30;
1928 	info->devtype->set_framerate(sd, &tpf);
1929 
1930 	v4l2_ctrl_handler_init(&info->hdl, 10);
1931 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1932 			V4L2_CID_BRIGHTNESS, 0, 255, 1, 128);
1933 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1934 			V4L2_CID_CONTRAST, 0, 127, 1, 64);
1935 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1936 			V4L2_CID_VFLIP, 0, 1, 1, 0);
1937 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1938 			V4L2_CID_HFLIP, 0, 1, 1, 0);
1939 	info->saturation = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1940 			V4L2_CID_SATURATION, 0, 256, 1, 128);
1941 	info->hue = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1942 			V4L2_CID_HUE, -180, 180, 5, 0);
1943 	info->gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1944 			V4L2_CID_GAIN, 0, 255, 1, 128);
1945 	info->auto_gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1946 			V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
1947 	info->exposure = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1948 			V4L2_CID_EXPOSURE, 0, 65535, 1, 500);
1949 	info->auto_exposure = v4l2_ctrl_new_std_menu(&info->hdl, &ov7670_ctrl_ops,
1950 			V4L2_CID_EXPOSURE_AUTO, V4L2_EXPOSURE_MANUAL, 0,
1951 			V4L2_EXPOSURE_AUTO);
1952 	v4l2_ctrl_new_std_menu_items(&info->hdl, &ov7670_ctrl_ops,
1953 			V4L2_CID_TEST_PATTERN,
1954 			ARRAY_SIZE(ov7670_test_pattern_menu) - 1, 0, 0,
1955 			ov7670_test_pattern_menu);
1956 	sd->ctrl_handler = &info->hdl;
1957 	if (info->hdl.error) {
1958 		ret = info->hdl.error;
1959 
1960 		goto hdl_free;
1961 	}
1962 	/*
1963 	 * We have checked empirically that hw allows to read back the gain
1964 	 * value chosen by auto gain but that's not the case for auto exposure.
1965 	 */
1966 	v4l2_ctrl_auto_cluster(2, &info->auto_gain, 0, true);
1967 	v4l2_ctrl_auto_cluster(2, &info->auto_exposure,
1968 			       V4L2_EXPOSURE_MANUAL, false);
1969 	v4l2_ctrl_cluster(2, &info->saturation);
1970 
1971 #if defined(CONFIG_MEDIA_CONTROLLER)
1972 	info->pad.flags = MEDIA_PAD_FL_SOURCE;
1973 	info->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
1974 	ret = media_entity_pads_init(&info->sd.entity, 1, &info->pad);
1975 	if (ret < 0)
1976 		goto hdl_free;
1977 #endif
1978 
1979 	v4l2_ctrl_handler_setup(&info->hdl);
1980 
1981 	ret = v4l2_async_register_subdev(&info->sd);
1982 	if (ret < 0)
1983 		goto entity_cleanup;
1984 
1985 	ov7670_power_off(sd);
1986 	return 0;
1987 
1988 entity_cleanup:
1989 	media_entity_cleanup(&info->sd.entity);
1990 hdl_free:
1991 	v4l2_ctrl_handler_free(&info->hdl);
1992 power_off:
1993 	ov7670_power_off(sd);
1994 	return ret;
1995 }
1996 
1997 static int ov7670_remove(struct i2c_client *client)
1998 {
1999 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
2000 	struct ov7670_info *info = to_state(sd);
2001 
2002 	v4l2_async_unregister_subdev(sd);
2003 	v4l2_ctrl_handler_free(&info->hdl);
2004 	media_entity_cleanup(&info->sd.entity);
2005 	ov7670_power_off(sd);
2006 	return 0;
2007 }
2008 
2009 static const struct i2c_device_id ov7670_id[] = {
2010 	{ "ov7670", MODEL_OV7670 },
2011 	{ "ov7675", MODEL_OV7675 },
2012 	{ }
2013 };
2014 MODULE_DEVICE_TABLE(i2c, ov7670_id);
2015 
2016 #if IS_ENABLED(CONFIG_OF)
2017 static const struct of_device_id ov7670_of_match[] = {
2018 	{ .compatible = "ovti,ov7670", },
2019 	{ /* sentinel */ },
2020 };
2021 MODULE_DEVICE_TABLE(of, ov7670_of_match);
2022 #endif
2023 
2024 static struct i2c_driver ov7670_driver = {
2025 	.driver = {
2026 		.name	= "ov7670",
2027 		.of_match_table = of_match_ptr(ov7670_of_match),
2028 	},
2029 	.probe		= ov7670_probe,
2030 	.remove		= ov7670_remove,
2031 	.id_table	= ov7670_id,
2032 };
2033 
2034 module_i2c_driver(ov7670_driver);
2035