xref: /linux/drivers/media/i2c/ov7670.c (revision 019b383d1132e4051de0d2e43254454b86538cf4)
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/consumer.h>
19 #include <media/v4l2-device.h>
20 #include <media/v4l2-event.h>
21 #include <media/v4l2-ctrls.h>
22 #include <media/v4l2-fwnode.h>
23 #include <media/v4l2-mediabus.h>
24 #include <media/v4l2-image-sizes.h>
25 #include <media/i2c/ov7670.h>
26 
27 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
28 MODULE_DESCRIPTION("A low-level driver for OmniVision ov7670 sensors");
29 MODULE_LICENSE("GPL");
30 
31 static bool debug;
32 module_param(debug, bool, 0644);
33 MODULE_PARM_DESC(debug, "Debug level (0-1)");
34 
35 /*
36  * The 7670 sits on i2c with ID 0x42
37  */
38 #define OV7670_I2C_ADDR 0x42
39 
40 #define PLL_FACTOR	4
41 
42 /* Registers */
43 #define REG_GAIN	0x00	/* Gain lower 8 bits (rest in vref) */
44 #define REG_BLUE	0x01	/* blue gain */
45 #define REG_RED		0x02	/* red gain */
46 #define REG_VREF	0x03	/* Pieces of GAIN, VSTART, VSTOP */
47 #define REG_COM1	0x04	/* Control 1 */
48 #define  COM1_CCIR656	  0x40  /* CCIR656 enable */
49 #define REG_BAVE	0x05	/* U/B Average level */
50 #define REG_GbAVE	0x06	/* Y/Gb Average level */
51 #define REG_AECHH	0x07	/* AEC MS 5 bits */
52 #define REG_RAVE	0x08	/* V/R Average level */
53 #define REG_COM2	0x09	/* Control 2 */
54 #define  COM2_SSLEEP	  0x10	/* Soft sleep mode */
55 #define REG_PID		0x0a	/* Product ID MSB */
56 #define REG_VER		0x0b	/* Product ID LSB */
57 #define REG_COM3	0x0c	/* Control 3 */
58 #define  COM3_SWAP	  0x40	  /* Byte swap */
59 #define  COM3_SCALEEN	  0x08	  /* Enable scaling */
60 #define  COM3_DCWEN	  0x04	  /* Enable downsamp/crop/window */
61 #define REG_COM4	0x0d	/* Control 4 */
62 #define REG_COM5	0x0e	/* All "reserved" */
63 #define REG_COM6	0x0f	/* Control 6 */
64 #define REG_AECH	0x10	/* More bits of AEC value */
65 #define REG_CLKRC	0x11	/* Clocl control */
66 #define   CLK_EXT	  0x40	  /* Use external clock directly */
67 #define   CLK_SCALE	  0x3f	  /* Mask for internal clock scale */
68 #define REG_COM7	0x12	/* Control 7 */
69 #define   COM7_RESET	  0x80	  /* Register reset */
70 #define   COM7_FMT_MASK	  0x38
71 #define   COM7_FMT_VGA	  0x00
72 #define	  COM7_FMT_CIF	  0x20	  /* CIF format */
73 #define   COM7_FMT_QVGA	  0x10	  /* QVGA format */
74 #define   COM7_FMT_QCIF	  0x08	  /* QCIF format */
75 #define	  COM7_RGB	  0x04	  /* bits 0 and 2 - RGB format */
76 #define	  COM7_YUV	  0x00	  /* YUV */
77 #define	  COM7_BAYER	  0x01	  /* Bayer format */
78 #define	  COM7_PBAYER	  0x05	  /* "Processed bayer" */
79 #define REG_COM8	0x13	/* Control 8 */
80 #define   COM8_FASTAEC	  0x80	  /* Enable fast AGC/AEC */
81 #define   COM8_AECSTEP	  0x40	  /* Unlimited AEC step size */
82 #define   COM8_BFILT	  0x20	  /* Band filter enable */
83 #define   COM8_AGC	  0x04	  /* Auto gain enable */
84 #define   COM8_AWB	  0x02	  /* White balance enable */
85 #define   COM8_AEC	  0x01	  /* Auto exposure enable */
86 #define REG_COM9	0x14	/* Control 9  - gain ceiling */
87 #define REG_COM10	0x15	/* Control 10 */
88 #define   COM10_HSYNC	  0x40	  /* HSYNC instead of HREF */
89 #define   COM10_PCLK_HB	  0x20	  /* Suppress PCLK on horiz blank */
90 #define   COM10_HREF_REV  0x08	  /* Reverse HREF */
91 #define   COM10_VS_LEAD	  0x04	  /* VSYNC on clock leading edge */
92 #define   COM10_VS_NEG	  0x02	  /* VSYNC negative */
93 #define   COM10_HS_NEG	  0x01	  /* HSYNC negative */
94 #define REG_HSTART	0x17	/* Horiz start high bits */
95 #define REG_HSTOP	0x18	/* Horiz stop high bits */
96 #define REG_VSTART	0x19	/* Vert start high bits */
97 #define REG_VSTOP	0x1a	/* Vert stop high bits */
98 #define REG_PSHFT	0x1b	/* Pixel delay after HREF */
99 #define REG_MIDH	0x1c	/* Manuf. ID high */
100 #define REG_MIDL	0x1d	/* Manuf. ID low */
101 #define REG_MVFP	0x1e	/* Mirror / vflip */
102 #define   MVFP_MIRROR	  0x20	  /* Mirror image */
103 #define   MVFP_FLIP	  0x10	  /* Vertical flip */
104 
105 #define REG_AEW		0x24	/* AGC upper limit */
106 #define REG_AEB		0x25	/* AGC lower limit */
107 #define REG_VPT		0x26	/* AGC/AEC fast mode op region */
108 #define REG_HSYST	0x30	/* HSYNC rising edge delay */
109 #define REG_HSYEN	0x31	/* HSYNC falling edge delay */
110 #define REG_HREF	0x32	/* HREF pieces */
111 #define REG_TSLB	0x3a	/* lots of stuff */
112 #define   TSLB_YLAST	  0x04	  /* UYVY or VYUY - see com13 */
113 #define REG_COM11	0x3b	/* Control 11 */
114 #define   COM11_NIGHT	  0x80	  /* NIght mode enable */
115 #define   COM11_NMFR	  0x60	  /* Two bit NM frame rate */
116 #define   COM11_HZAUTO	  0x10	  /* Auto detect 50/60 Hz */
117 #define	  COM11_50HZ	  0x08	  /* Manual 50Hz select */
118 #define   COM11_EXP	  0x02
119 #define REG_COM12	0x3c	/* Control 12 */
120 #define   COM12_HREF	  0x80	  /* HREF always */
121 #define REG_COM13	0x3d	/* Control 13 */
122 #define   COM13_GAMMA	  0x80	  /* Gamma enable */
123 #define	  COM13_UVSAT	  0x40	  /* UV saturation auto adjustment */
124 #define   COM13_UVSWAP	  0x01	  /* V before U - w/TSLB */
125 #define REG_COM14	0x3e	/* Control 14 */
126 #define   COM14_DCWEN	  0x10	  /* DCW/PCLK-scale enable */
127 #define REG_EDGE	0x3f	/* Edge enhancement factor */
128 #define REG_COM15	0x40	/* Control 15 */
129 #define   COM15_R10F0	  0x00	  /* Data range 10 to F0 */
130 #define	  COM15_R01FE	  0x80	  /*            01 to FE */
131 #define   COM15_R00FF	  0xc0	  /*            00 to FF */
132 #define   COM15_RGB565	  0x10	  /* RGB565 output */
133 #define   COM15_RGB555	  0x30	  /* RGB555 output */
134 #define REG_COM16	0x41	/* Control 16 */
135 #define   COM16_AWBGAIN   0x08	  /* AWB gain enable */
136 #define REG_COM17	0x42	/* Control 17 */
137 #define   COM17_AECWIN	  0xc0	  /* AEC window - must match COM4 */
138 #define   COM17_CBAR	  0x08	  /* DSP Color bar */
139 
140 /*
141  * This matrix defines how the colors are generated, must be
142  * tweaked to adjust hue and saturation.
143  *
144  * Order: v-red, v-green, v-blue, u-red, u-green, u-blue
145  *
146  * They are nine-bit signed quantities, with the sign bit
147  * stored in 0x58.  Sign for v-red is bit 0, and up from there.
148  */
149 #define	REG_CMATRIX_BASE 0x4f
150 #define   CMATRIX_LEN 6
151 #define REG_CMATRIX_SIGN 0x58
152 
153 
154 #define REG_BRIGHT	0x55	/* Brightness */
155 #define REG_CONTRAS	0x56	/* Contrast control */
156 
157 #define REG_GFIX	0x69	/* Fix gain control */
158 
159 #define REG_DBLV	0x6b	/* PLL control an debugging */
160 #define   DBLV_BYPASS	  0x0a	  /* Bypass PLL */
161 #define   DBLV_X4	  0x4a	  /* clock x4 */
162 #define   DBLV_X6	  0x8a	  /* clock x6 */
163 #define   DBLV_X8	  0xca	  /* clock x8 */
164 
165 #define REG_SCALING_XSC	0x70	/* Test pattern and horizontal scale factor */
166 #define   TEST_PATTTERN_0 0x80
167 #define REG_SCALING_YSC	0x71	/* Test pattern and vertical scale factor */
168 #define   TEST_PATTTERN_1 0x80
169 
170 #define REG_REG76	0x76	/* OV's name */
171 #define   R76_BLKPCOR	  0x80	  /* Black pixel correction enable */
172 #define   R76_WHTPCOR	  0x40	  /* White pixel correction enable */
173 
174 #define REG_RGB444	0x8c	/* RGB 444 control */
175 #define   R444_ENABLE	  0x02	  /* Turn on RGB444, overrides 5x5 */
176 #define   R444_RGBX	  0x01	  /* Empty nibble at end */
177 
178 #define REG_HAECC1	0x9f	/* Hist AEC/AGC control 1 */
179 #define REG_HAECC2	0xa0	/* Hist AEC/AGC control 2 */
180 
181 #define REG_BD50MAX	0xa5	/* 50hz banding step limit */
182 #define REG_HAECC3	0xa6	/* Hist AEC/AGC control 3 */
183 #define REG_HAECC4	0xa7	/* Hist AEC/AGC control 4 */
184 #define REG_HAECC5	0xa8	/* Hist AEC/AGC control 5 */
185 #define REG_HAECC6	0xa9	/* Hist AEC/AGC control 6 */
186 #define REG_HAECC7	0xaa	/* Hist AEC/AGC control 7 */
187 #define REG_BD60MAX	0xab	/* 60hz banding step limit */
188 
189 enum ov7670_model {
190 	MODEL_OV7670 = 0,
191 	MODEL_OV7675,
192 };
193 
194 struct ov7670_win_size {
195 	int	width;
196 	int	height;
197 	unsigned char com7_bit;
198 	int	hstart;		/* Start/stop values for the camera.  Note */
199 	int	hstop;		/* that they do not always make complete */
200 	int	vstart;		/* sense to humans, but evidently the sensor */
201 	int	vstop;		/* will do the right thing... */
202 	struct regval_list *regs; /* Regs to tweak */
203 };
204 
205 struct ov7670_devtype {
206 	/* formats supported for each model */
207 	struct ov7670_win_size *win_sizes;
208 	unsigned int n_win_sizes;
209 	/* callbacks for frame rate control */
210 	int (*set_framerate)(struct v4l2_subdev *, struct v4l2_fract *);
211 	void (*get_framerate)(struct v4l2_subdev *, struct v4l2_fract *);
212 };
213 
214 /*
215  * Information we maintain about a known sensor.
216  */
217 struct ov7670_format_struct;  /* coming later */
218 struct ov7670_info {
219 	struct v4l2_subdev sd;
220 #if defined(CONFIG_MEDIA_CONTROLLER)
221 	struct media_pad pad;
222 #endif
223 	struct v4l2_ctrl_handler hdl;
224 	struct {
225 		/* gain cluster */
226 		struct v4l2_ctrl *auto_gain;
227 		struct v4l2_ctrl *gain;
228 	};
229 	struct {
230 		/* exposure cluster */
231 		struct v4l2_ctrl *auto_exposure;
232 		struct v4l2_ctrl *exposure;
233 	};
234 	struct {
235 		/* saturation/hue cluster */
236 		struct v4l2_ctrl *saturation;
237 		struct v4l2_ctrl *hue;
238 	};
239 	struct v4l2_mbus_framefmt format;
240 	struct ov7670_format_struct *fmt;  /* Current format */
241 	struct ov7670_win_size *wsize;
242 	struct clk *clk;
243 	int on;
244 	struct gpio_desc *resetb_gpio;
245 	struct gpio_desc *pwdn_gpio;
246 	unsigned int mbus_config;	/* Media bus configuration flags */
247 	int min_width;			/* Filter out smaller sizes */
248 	int min_height;			/* Filter out smaller sizes */
249 	int clock_speed;		/* External clock speed (MHz) */
250 	u8 clkrc;			/* Clock divider value */
251 	bool use_smbus;			/* Use smbus I/O instead of I2C */
252 	bool pll_bypass;
253 	bool pclk_hb_disable;
254 	const struct ov7670_devtype *devtype; /* Device specifics */
255 };
256 
257 static inline struct ov7670_info *to_state(struct v4l2_subdev *sd)
258 {
259 	return container_of(sd, struct ov7670_info, sd);
260 }
261 
262 static inline struct v4l2_subdev *to_sd(struct v4l2_ctrl *ctrl)
263 {
264 	return &container_of(ctrl->handler, struct ov7670_info, hdl)->sd;
265 }
266 
267 
268 
269 /*
270  * The default register settings, as obtained from OmniVision.  There
271  * is really no making sense of most of these - lots of "reserved" values
272  * and such.
273  *
274  * These settings give VGA YUYV.
275  */
276 
277 struct regval_list {
278 	unsigned char reg_num;
279 	unsigned char value;
280 };
281 
282 static struct regval_list ov7670_default_regs[] = {
283 	{ REG_COM7, COM7_RESET },
284 /*
285  * Clock scale: 3 = 15fps
286  *              2 = 20fps
287  *              1 = 30fps
288  */
289 	{ REG_CLKRC, 0x1 },	/* OV: clock scale (30 fps) */
290 	{ REG_TSLB,  0x04 },	/* OV */
291 	{ REG_COM7, 0 },	/* VGA */
292 	/*
293 	 * Set the hardware window.  These values from OV don't entirely
294 	 * make sense - hstop is less than hstart.  But they work...
295 	 */
296 	{ REG_HSTART, 0x13 },	{ REG_HSTOP, 0x01 },
297 	{ REG_HREF, 0xb6 },	{ REG_VSTART, 0x02 },
298 	{ REG_VSTOP, 0x7a },	{ REG_VREF, 0x0a },
299 
300 	{ REG_COM3, 0 },	{ REG_COM14, 0 },
301 	/* Mystery scaling numbers */
302 	{ REG_SCALING_XSC, 0x3a },
303 	{ REG_SCALING_YSC, 0x35 },
304 	{ 0x72, 0x11 },		{ 0x73, 0xf0 },
305 	{ 0xa2, 0x02 },		{ REG_COM10, 0x0 },
306 
307 	/* Gamma curve values */
308 	{ 0x7a, 0x20 },		{ 0x7b, 0x10 },
309 	{ 0x7c, 0x1e },		{ 0x7d, 0x35 },
310 	{ 0x7e, 0x5a },		{ 0x7f, 0x69 },
311 	{ 0x80, 0x76 },		{ 0x81, 0x80 },
312 	{ 0x82, 0x88 },		{ 0x83, 0x8f },
313 	{ 0x84, 0x96 },		{ 0x85, 0xa3 },
314 	{ 0x86, 0xaf },		{ 0x87, 0xc4 },
315 	{ 0x88, 0xd7 },		{ 0x89, 0xe8 },
316 
317 	/* AGC and AEC parameters.  Note we start by disabling those features,
318 	   then turn them only after tweaking the values. */
319 	{ REG_COM8, COM8_FASTAEC | COM8_AECSTEP | COM8_BFILT },
320 	{ REG_GAIN, 0 },	{ REG_AECH, 0 },
321 	{ REG_COM4, 0x40 }, /* magic reserved bit */
322 	{ REG_COM9, 0x18 }, /* 4x gain + magic rsvd bit */
323 	{ REG_BD50MAX, 0x05 },	{ REG_BD60MAX, 0x07 },
324 	{ REG_AEW, 0x95 },	{ REG_AEB, 0x33 },
325 	{ REG_VPT, 0xe3 },	{ REG_HAECC1, 0x78 },
326 	{ REG_HAECC2, 0x68 },	{ 0xa1, 0x03 }, /* magic */
327 	{ REG_HAECC3, 0xd8 },	{ REG_HAECC4, 0xd8 },
328 	{ REG_HAECC5, 0xf0 },	{ REG_HAECC6, 0x90 },
329 	{ REG_HAECC7, 0x94 },
330 	{ REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC },
331 
332 	/* Almost all of these are magic "reserved" values.  */
333 	{ REG_COM5, 0x61 },	{ REG_COM6, 0x4b },
334 	{ 0x16, 0x02 },		{ REG_MVFP, 0x07 },
335 	{ 0x21, 0x02 },		{ 0x22, 0x91 },
336 	{ 0x29, 0x07 },		{ 0x33, 0x0b },
337 	{ 0x35, 0x0b },		{ 0x37, 0x1d },
338 	{ 0x38, 0x71 },		{ 0x39, 0x2a },
339 	{ REG_COM12, 0x78 },	{ 0x4d, 0x40 },
340 	{ 0x4e, 0x20 },		{ REG_GFIX, 0 },
341 	{ 0x6b, 0x4a },		{ 0x74, 0x10 },
342 	{ 0x8d, 0x4f },		{ 0x8e, 0 },
343 	{ 0x8f, 0 },		{ 0x90, 0 },
344 	{ 0x91, 0 },		{ 0x96, 0 },
345 	{ 0x9a, 0 },		{ 0xb0, 0x84 },
346 	{ 0xb1, 0x0c },		{ 0xb2, 0x0e },
347 	{ 0xb3, 0x82 },		{ 0xb8, 0x0a },
348 
349 	/* More reserved magic, some of which tweaks white balance */
350 	{ 0x43, 0x0a },		{ 0x44, 0xf0 },
351 	{ 0x45, 0x34 },		{ 0x46, 0x58 },
352 	{ 0x47, 0x28 },		{ 0x48, 0x3a },
353 	{ 0x59, 0x88 },		{ 0x5a, 0x88 },
354 	{ 0x5b, 0x44 },		{ 0x5c, 0x67 },
355 	{ 0x5d, 0x49 },		{ 0x5e, 0x0e },
356 	{ 0x6c, 0x0a },		{ 0x6d, 0x55 },
357 	{ 0x6e, 0x11 },		{ 0x6f, 0x9f }, /* "9e for advance AWB" */
358 	{ 0x6a, 0x40 },		{ REG_BLUE, 0x40 },
359 	{ REG_RED, 0x60 },
360 	{ REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC|COM8_AWB },
361 
362 	/* Matrix coefficients */
363 	{ 0x4f, 0x80 },		{ 0x50, 0x80 },
364 	{ 0x51, 0 },		{ 0x52, 0x22 },
365 	{ 0x53, 0x5e },		{ 0x54, 0x80 },
366 	{ 0x58, 0x9e },
367 
368 	{ REG_COM16, COM16_AWBGAIN },	{ REG_EDGE, 0 },
369 	{ 0x75, 0x05 },		{ 0x76, 0xe1 },
370 	{ 0x4c, 0 },		{ 0x77, 0x01 },
371 	{ REG_COM13, 0xc3 },	{ 0x4b, 0x09 },
372 	{ 0xc9, 0x60 },		{ REG_COM16, 0x38 },
373 	{ 0x56, 0x40 },
374 
375 	{ 0x34, 0x11 },		{ REG_COM11, COM11_EXP|COM11_HZAUTO },
376 	{ 0xa4, 0x88 },		{ 0x96, 0 },
377 	{ 0x97, 0x30 },		{ 0x98, 0x20 },
378 	{ 0x99, 0x30 },		{ 0x9a, 0x84 },
379 	{ 0x9b, 0x29 },		{ 0x9c, 0x03 },
380 	{ 0x9d, 0x4c },		{ 0x9e, 0x3f },
381 	{ 0x78, 0x04 },
382 
383 	/* Extra-weird stuff.  Some sort of multiplexor register */
384 	{ 0x79, 0x01 },		{ 0xc8, 0xf0 },
385 	{ 0x79, 0x0f },		{ 0xc8, 0x00 },
386 	{ 0x79, 0x10 },		{ 0xc8, 0x7e },
387 	{ 0x79, 0x0a },		{ 0xc8, 0x80 },
388 	{ 0x79, 0x0b },		{ 0xc8, 0x01 },
389 	{ 0x79, 0x0c },		{ 0xc8, 0x0f },
390 	{ 0x79, 0x0d },		{ 0xc8, 0x20 },
391 	{ 0x79, 0x09 },		{ 0xc8, 0x80 },
392 	{ 0x79, 0x02 },		{ 0xc8, 0xc0 },
393 	{ 0x79, 0x03 },		{ 0xc8, 0x40 },
394 	{ 0x79, 0x05 },		{ 0xc8, 0x30 },
395 	{ 0x79, 0x26 },
396 
397 	{ 0xff, 0xff },	/* END MARKER */
398 };
399 
400 
401 /*
402  * Here we'll try to encapsulate the changes for just the output
403  * video format.
404  *
405  * RGB656 and YUV422 come from OV; RGB444 is homebrewed.
406  *
407  * IMPORTANT RULE: the first entry must be for COM7, see ov7670_s_fmt for why.
408  */
409 
410 
411 static struct regval_list ov7670_fmt_yuv422[] = {
412 	{ REG_COM7, 0x0 },  /* Selects YUV mode */
413 	{ REG_RGB444, 0 },	/* No RGB444 please */
414 	{ REG_COM1, 0 },	/* CCIR601 */
415 	{ REG_COM15, COM15_R00FF },
416 	{ REG_COM9, 0x48 }, /* 32x gain ceiling; 0x8 is reserved bit */
417 	{ 0x4f, 0x80 },		/* "matrix coefficient 1" */
418 	{ 0x50, 0x80 },		/* "matrix coefficient 2" */
419 	{ 0x51, 0    },		/* vb */
420 	{ 0x52, 0x22 },		/* "matrix coefficient 4" */
421 	{ 0x53, 0x5e },		/* "matrix coefficient 5" */
422 	{ 0x54, 0x80 },		/* "matrix coefficient 6" */
423 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT },
424 	{ 0xff, 0xff },
425 };
426 
427 static struct regval_list ov7670_fmt_rgb565[] = {
428 	{ REG_COM7, COM7_RGB },	/* Selects RGB mode */
429 	{ REG_RGB444, 0 },	/* No RGB444 please */
430 	{ REG_COM1, 0x0 },	/* CCIR601 */
431 	{ REG_COM15, COM15_RGB565 },
432 	{ REG_COM9, 0x38 },	/* 16x gain ceiling; 0x8 is reserved bit */
433 	{ 0x4f, 0xb3 },		/* "matrix coefficient 1" */
434 	{ 0x50, 0xb3 },		/* "matrix coefficient 2" */
435 	{ 0x51, 0    },		/* vb */
436 	{ 0x52, 0x3d },		/* "matrix coefficient 4" */
437 	{ 0x53, 0xa7 },		/* "matrix coefficient 5" */
438 	{ 0x54, 0xe4 },		/* "matrix coefficient 6" */
439 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT },
440 	{ 0xff, 0xff },
441 };
442 
443 static struct regval_list ov7670_fmt_rgb444[] = {
444 	{ REG_COM7, COM7_RGB },	/* Selects RGB mode */
445 	{ REG_RGB444, R444_ENABLE },	/* Enable xxxxrrrr ggggbbbb */
446 	{ REG_COM1, 0x0 },	/* CCIR601 */
447 	{ REG_COM15, COM15_R01FE|COM15_RGB565 }, /* Data range needed? */
448 	{ REG_COM9, 0x38 },	/* 16x gain ceiling; 0x8 is reserved bit */
449 	{ 0x4f, 0xb3 },		/* "matrix coefficient 1" */
450 	{ 0x50, 0xb3 },		/* "matrix coefficient 2" */
451 	{ 0x51, 0    },		/* vb */
452 	{ 0x52, 0x3d },		/* "matrix coefficient 4" */
453 	{ 0x53, 0xa7 },		/* "matrix coefficient 5" */
454 	{ 0x54, 0xe4 },		/* "matrix coefficient 6" */
455 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT|0x2 },  /* Magic rsvd bit */
456 	{ 0xff, 0xff },
457 };
458 
459 static struct regval_list ov7670_fmt_raw[] = {
460 	{ REG_COM7, COM7_BAYER },
461 	{ REG_COM13, 0x08 }, /* No gamma, magic rsvd bit */
462 	{ REG_COM16, 0x3d }, /* Edge enhancement, denoise */
463 	{ REG_REG76, 0xe1 }, /* Pix correction, magic rsvd */
464 	{ 0xff, 0xff },
465 };
466 
467 
468 
469 /*
470  * Low-level register I/O.
471  *
472  * Note that there are two versions of these.  On the XO 1, the
473  * i2c controller only does SMBUS, so that's what we use.  The
474  * ov7670 is not really an SMBUS device, though, so the communication
475  * is not always entirely reliable.
476  */
477 static int ov7670_read_smbus(struct v4l2_subdev *sd, unsigned char reg,
478 		unsigned char *value)
479 {
480 	struct i2c_client *client = v4l2_get_subdevdata(sd);
481 	int ret;
482 
483 	ret = i2c_smbus_read_byte_data(client, reg);
484 	if (ret >= 0) {
485 		*value = (unsigned char)ret;
486 		ret = 0;
487 	}
488 	return ret;
489 }
490 
491 
492 static int ov7670_write_smbus(struct v4l2_subdev *sd, unsigned char reg,
493 		unsigned char value)
494 {
495 	struct i2c_client *client = v4l2_get_subdevdata(sd);
496 	int ret = i2c_smbus_write_byte_data(client, reg, value);
497 
498 	if (reg == REG_COM7 && (value & COM7_RESET))
499 		msleep(5);  /* Wait for reset to run */
500 	return ret;
501 }
502 
503 /*
504  * On most platforms, we'd rather do straight i2c I/O.
505  */
506 static int ov7670_read_i2c(struct v4l2_subdev *sd, unsigned char reg,
507 		unsigned char *value)
508 {
509 	struct i2c_client *client = v4l2_get_subdevdata(sd);
510 	u8 data = reg;
511 	struct i2c_msg msg;
512 	int ret;
513 
514 	/*
515 	 * Send out the register address...
516 	 */
517 	msg.addr = client->addr;
518 	msg.flags = 0;
519 	msg.len = 1;
520 	msg.buf = &data;
521 	ret = i2c_transfer(client->adapter, &msg, 1);
522 	if (ret < 0) {
523 		printk(KERN_ERR "Error %d on register write\n", ret);
524 		return ret;
525 	}
526 	/*
527 	 * ...then read back the result.
528 	 */
529 	msg.flags = I2C_M_RD;
530 	ret = i2c_transfer(client->adapter, &msg, 1);
531 	if (ret >= 0) {
532 		*value = data;
533 		ret = 0;
534 	}
535 	return ret;
536 }
537 
538 
539 static int ov7670_write_i2c(struct v4l2_subdev *sd, unsigned char reg,
540 		unsigned char value)
541 {
542 	struct i2c_client *client = v4l2_get_subdevdata(sd);
543 	struct i2c_msg msg;
544 	unsigned char data[2] = { reg, value };
545 	int ret;
546 
547 	msg.addr = client->addr;
548 	msg.flags = 0;
549 	msg.len = 2;
550 	msg.buf = data;
551 	ret = i2c_transfer(client->adapter, &msg, 1);
552 	if (ret > 0)
553 		ret = 0;
554 	if (reg == REG_COM7 && (value & COM7_RESET))
555 		msleep(5);  /* Wait for reset to run */
556 	return ret;
557 }
558 
559 static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
560 		unsigned char *value)
561 {
562 	struct ov7670_info *info = to_state(sd);
563 
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 
575 	if (info->use_smbus)
576 		return ov7670_write_smbus(sd, reg, value);
577 	else
578 		return ov7670_write_i2c(sd, reg, value);
579 }
580 
581 static int ov7670_update_bits(struct v4l2_subdev *sd, unsigned char reg,
582 		unsigned char mask, unsigned char value)
583 {
584 	unsigned char orig;
585 	int ret;
586 
587 	ret = ov7670_read(sd, reg, &orig);
588 	if (ret)
589 		return ret;
590 
591 	return ov7670_write(sd, reg, (orig & ~mask) | (value & mask));
592 }
593 
594 /*
595  * Write a list of register settings; ff/ff stops the process.
596  */
597 static int ov7670_write_array(struct v4l2_subdev *sd, struct regval_list *vals)
598 {
599 	while (vals->reg_num != 0xff || vals->value != 0xff) {
600 		int ret = ov7670_write(sd, vals->reg_num, vals->value);
601 
602 		if (ret < 0)
603 			return ret;
604 		vals++;
605 	}
606 	return 0;
607 }
608 
609 
610 /*
611  * Stuff that knows about the sensor.
612  */
613 static int ov7670_reset(struct v4l2_subdev *sd, u32 val)
614 {
615 	ov7670_write(sd, REG_COM7, COM7_RESET);
616 	msleep(1);
617 	return 0;
618 }
619 
620 
621 static int ov7670_init(struct v4l2_subdev *sd, u32 val)
622 {
623 	return ov7670_write_array(sd, ov7670_default_regs);
624 }
625 
626 static int ov7670_detect(struct v4l2_subdev *sd)
627 {
628 	unsigned char v;
629 	int ret;
630 
631 	ret = ov7670_init(sd, 0);
632 	if (ret < 0)
633 		return ret;
634 	ret = ov7670_read(sd, REG_MIDH, &v);
635 	if (ret < 0)
636 		return ret;
637 	if (v != 0x7f) /* OV manuf. id. */
638 		return -ENODEV;
639 	ret = ov7670_read(sd, REG_MIDL, &v);
640 	if (ret < 0)
641 		return ret;
642 	if (v != 0xa2)
643 		return -ENODEV;
644 	/*
645 	 * OK, we know we have an OmniVision chip...but which one?
646 	 */
647 	ret = ov7670_read(sd, REG_PID, &v);
648 	if (ret < 0)
649 		return ret;
650 	if (v != 0x76)  /* PID + VER = 0x76 / 0x73 */
651 		return -ENODEV;
652 	ret = ov7670_read(sd, REG_VER, &v);
653 	if (ret < 0)
654 		return ret;
655 	if (v != 0x73)  /* PID + VER = 0x76 / 0x73 */
656 		return -ENODEV;
657 	return 0;
658 }
659 
660 
661 /*
662  * Store information about the video data format.  The color matrix
663  * is deeply tied into the format, so keep the relevant values here.
664  * The magic matrix numbers come from OmniVision.
665  */
666 static struct ov7670_format_struct {
667 	u32 mbus_code;
668 	enum v4l2_colorspace colorspace;
669 	struct regval_list *regs;
670 	int cmatrix[CMATRIX_LEN];
671 } ov7670_formats[] = {
672 	{
673 		.mbus_code	= MEDIA_BUS_FMT_YUYV8_2X8,
674 		.colorspace	= V4L2_COLORSPACE_SRGB,
675 		.regs		= ov7670_fmt_yuv422,
676 		.cmatrix	= { 128, -128, 0, -34, -94, 128 },
677 	},
678 	{
679 		.mbus_code	= MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE,
680 		.colorspace	= V4L2_COLORSPACE_SRGB,
681 		.regs		= ov7670_fmt_rgb444,
682 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
683 	},
684 	{
685 		.mbus_code	= MEDIA_BUS_FMT_RGB565_2X8_LE,
686 		.colorspace	= V4L2_COLORSPACE_SRGB,
687 		.regs		= ov7670_fmt_rgb565,
688 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
689 	},
690 	{
691 		.mbus_code	= MEDIA_BUS_FMT_SBGGR8_1X8,
692 		.colorspace	= V4L2_COLORSPACE_SRGB,
693 		.regs		= ov7670_fmt_raw,
694 		.cmatrix	= { 0, 0, 0, 0, 0, 0 },
695 	},
696 };
697 #define N_OV7670_FMTS ARRAY_SIZE(ov7670_formats)
698 
699 
700 /*
701  * Then there is the issue of window sizes.  Try to capture the info here.
702  */
703 
704 /*
705  * QCIF mode is done (by OV) in a very strange way - it actually looks like
706  * VGA with weird scaling options - they do *not* use the canned QCIF mode
707  * which is allegedly provided by the sensor.  So here's the weird register
708  * settings.
709  */
710 static struct regval_list ov7670_qcif_regs[] = {
711 	{ REG_COM3, COM3_SCALEEN|COM3_DCWEN },
712 	{ REG_COM3, COM3_DCWEN },
713 	{ REG_COM14, COM14_DCWEN | 0x01},
714 	{ 0x73, 0xf1 },
715 	{ 0xa2, 0x52 },
716 	{ 0x7b, 0x1c },
717 	{ 0x7c, 0x28 },
718 	{ 0x7d, 0x3c },
719 	{ 0x7f, 0x69 },
720 	{ REG_COM9, 0x38 },
721 	{ 0xa1, 0x0b },
722 	{ 0x74, 0x19 },
723 	{ 0x9a, 0x80 },
724 	{ 0x43, 0x14 },
725 	{ REG_COM13, 0xc0 },
726 	{ 0xff, 0xff },
727 };
728 
729 static struct ov7670_win_size ov7670_win_sizes[] = {
730 	/* VGA */
731 	{
732 		.width		= VGA_WIDTH,
733 		.height		= VGA_HEIGHT,
734 		.com7_bit	= COM7_FMT_VGA,
735 		.hstart		= 158,	/* These values from */
736 		.hstop		=  14,	/* Omnivision */
737 		.vstart		=  10,
738 		.vstop		= 490,
739 		.regs		= NULL,
740 	},
741 	/* CIF */
742 	{
743 		.width		= CIF_WIDTH,
744 		.height		= CIF_HEIGHT,
745 		.com7_bit	= COM7_FMT_CIF,
746 		.hstart		= 170,	/* Empirically determined */
747 		.hstop		=  90,
748 		.vstart		=  14,
749 		.vstop		= 494,
750 		.regs		= NULL,
751 	},
752 	/* QVGA */
753 	{
754 		.width		= QVGA_WIDTH,
755 		.height		= QVGA_HEIGHT,
756 		.com7_bit	= COM7_FMT_QVGA,
757 		.hstart		= 168,	/* Empirically determined */
758 		.hstop		=  24,
759 		.vstart		=  12,
760 		.vstop		= 492,
761 		.regs		= NULL,
762 	},
763 	/* QCIF */
764 	{
765 		.width		= QCIF_WIDTH,
766 		.height		= QCIF_HEIGHT,
767 		.com7_bit	= COM7_FMT_VGA, /* see comment above */
768 		.hstart		= 456,	/* Empirically determined */
769 		.hstop		=  24,
770 		.vstart		=  14,
771 		.vstop		= 494,
772 		.regs		= ov7670_qcif_regs,
773 	}
774 };
775 
776 static struct ov7670_win_size ov7675_win_sizes[] = {
777 	/*
778 	 * Currently, only VGA is supported. Theoretically it could be possible
779 	 * to support CIF, QVGA and QCIF too. Taking values for ov7670 as a
780 	 * base and tweak them empirically could be required.
781 	 */
782 	{
783 		.width		= VGA_WIDTH,
784 		.height		= VGA_HEIGHT,
785 		.com7_bit	= COM7_FMT_VGA,
786 		.hstart		= 158,	/* These values from */
787 		.hstop		=  14,	/* Omnivision */
788 		.vstart		=  14,  /* Empirically determined */
789 		.vstop		= 494,
790 		.regs		= NULL,
791 	}
792 };
793 
794 static void ov7675_get_framerate(struct v4l2_subdev *sd,
795 				 struct v4l2_fract *tpf)
796 {
797 	struct ov7670_info *info = to_state(sd);
798 	u32 clkrc = info->clkrc;
799 	int pll_factor;
800 
801 	if (info->pll_bypass)
802 		pll_factor = 1;
803 	else
804 		pll_factor = PLL_FACTOR;
805 
806 	clkrc++;
807 	if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
808 		clkrc = (clkrc >> 1);
809 
810 	tpf->numerator = 1;
811 	tpf->denominator = (5 * pll_factor * info->clock_speed) /
812 			(4 * clkrc);
813 }
814 
815 static int ov7675_apply_framerate(struct v4l2_subdev *sd)
816 {
817 	struct ov7670_info *info = to_state(sd);
818 	int ret;
819 
820 	ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
821 	if (ret < 0)
822 		return ret;
823 
824 	return ov7670_write(sd, REG_DBLV,
825 			    info->pll_bypass ? DBLV_BYPASS : DBLV_X4);
826 }
827 
828 static int ov7675_set_framerate(struct v4l2_subdev *sd,
829 				 struct v4l2_fract *tpf)
830 {
831 	struct ov7670_info *info = to_state(sd);
832 	u32 clkrc;
833 	int pll_factor;
834 
835 	/*
836 	 * The formula is fps = 5/4*pixclk for YUV/RGB and
837 	 * fps = 5/2*pixclk for RAW.
838 	 *
839 	 * pixclk = clock_speed / (clkrc + 1) * PLLfactor
840 	 *
841 	 */
842 	if (tpf->numerator == 0 || tpf->denominator == 0) {
843 		clkrc = 0;
844 	} else {
845 		pll_factor = info->pll_bypass ? 1 : PLL_FACTOR;
846 		clkrc = (5 * pll_factor * info->clock_speed * tpf->numerator) /
847 			(4 * tpf->denominator);
848 		if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
849 			clkrc = (clkrc << 1);
850 		clkrc--;
851 	}
852 
853 	/*
854 	 * The datasheet claims that clkrc = 0 will divide the input clock by 1
855 	 * but we've checked with an oscilloscope that it divides by 2 instead.
856 	 * So, if clkrc = 0 just bypass the divider.
857 	 */
858 	if (clkrc <= 0)
859 		clkrc = CLK_EXT;
860 	else if (clkrc > CLK_SCALE)
861 		clkrc = CLK_SCALE;
862 	info->clkrc = clkrc;
863 
864 	/* Recalculate frame rate */
865 	ov7675_get_framerate(sd, tpf);
866 
867 	/*
868 	 * If the device is not powered up by the host driver do
869 	 * not apply any changes to H/W at this time. Instead
870 	 * the framerate will be restored right after power-up.
871 	 */
872 	if (info->on)
873 		return ov7675_apply_framerate(sd);
874 
875 	return 0;
876 }
877 
878 static void ov7670_get_framerate_legacy(struct v4l2_subdev *sd,
879 				 struct v4l2_fract *tpf)
880 {
881 	struct ov7670_info *info = to_state(sd);
882 
883 	tpf->numerator = 1;
884 	tpf->denominator = info->clock_speed;
885 	if ((info->clkrc & CLK_EXT) == 0 && (info->clkrc & CLK_SCALE) > 1)
886 		tpf->denominator /= (info->clkrc & CLK_SCALE);
887 }
888 
889 static int ov7670_set_framerate_legacy(struct v4l2_subdev *sd,
890 					struct v4l2_fract *tpf)
891 {
892 	struct ov7670_info *info = to_state(sd);
893 	int div;
894 
895 	if (tpf->numerator == 0 || tpf->denominator == 0)
896 		div = 1;  /* Reset to full rate */
897 	else
898 		div = (tpf->numerator * info->clock_speed) / tpf->denominator;
899 	if (div == 0)
900 		div = 1;
901 	else if (div > CLK_SCALE)
902 		div = CLK_SCALE;
903 	info->clkrc = (info->clkrc & 0x80) | div;
904 	tpf->numerator = 1;
905 	tpf->denominator = info->clock_speed / div;
906 
907 	/*
908 	 * If the device is not powered up by the host driver do
909 	 * not apply any changes to H/W at this time. Instead
910 	 * the framerate will be restored right after power-up.
911 	 */
912 	if (info->on)
913 		return ov7670_write(sd, REG_CLKRC, info->clkrc);
914 
915 	return 0;
916 }
917 
918 /*
919  * Store a set of start/stop values into the camera.
920  */
921 static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop,
922 		int vstart, int vstop)
923 {
924 	int ret;
925 	unsigned char v;
926 	/*
927 	 * Horizontal: 11 bits, top 8 live in hstart and hstop.  Bottom 3 of
928 	 * hstart are in href[2:0], bottom 3 of hstop in href[5:3].  There is
929 	 * a mystery "edge offset" value in the top two bits of href.
930 	 */
931 	ret = ov7670_write(sd, REG_HSTART, (hstart >> 3) & 0xff);
932 	if (ret)
933 		return ret;
934 	ret = ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff);
935 	if (ret)
936 		return ret;
937 	ret = ov7670_read(sd, REG_HREF, &v);
938 	if (ret)
939 		return ret;
940 	v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7);
941 	msleep(10);
942 	ret = ov7670_write(sd, REG_HREF, v);
943 	if (ret)
944 		return ret;
945 	/* Vertical: similar arrangement, but only 10 bits. */
946 	ret = ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff);
947 	if (ret)
948 		return ret;
949 	ret = ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff);
950 	if (ret)
951 		return ret;
952 	ret = ov7670_read(sd, REG_VREF, &v);
953 	if (ret)
954 		return ret;
955 	v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3);
956 	msleep(10);
957 	return ov7670_write(sd, REG_VREF, v);
958 }
959 
960 
961 static int ov7670_enum_mbus_code(struct v4l2_subdev *sd,
962 		struct v4l2_subdev_state *sd_state,
963 		struct v4l2_subdev_mbus_code_enum *code)
964 {
965 	if (code->pad || code->index >= N_OV7670_FMTS)
966 		return -EINVAL;
967 
968 	code->code = ov7670_formats[code->index].mbus_code;
969 	return 0;
970 }
971 
972 static int ov7670_try_fmt_internal(struct v4l2_subdev *sd,
973 		struct v4l2_mbus_framefmt *fmt,
974 		struct ov7670_format_struct **ret_fmt,
975 		struct ov7670_win_size **ret_wsize)
976 {
977 	int index, i;
978 	struct ov7670_win_size *wsize;
979 	struct ov7670_info *info = to_state(sd);
980 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
981 	unsigned int win_sizes_limit = n_win_sizes;
982 
983 	for (index = 0; index < N_OV7670_FMTS; index++)
984 		if (ov7670_formats[index].mbus_code == fmt->code)
985 			break;
986 	if (index >= N_OV7670_FMTS) {
987 		/* default to first format */
988 		index = 0;
989 		fmt->code = ov7670_formats[0].mbus_code;
990 	}
991 	if (ret_fmt != NULL)
992 		*ret_fmt = ov7670_formats + index;
993 	/*
994 	 * Fields: the OV devices claim to be progressive.
995 	 */
996 	fmt->field = V4L2_FIELD_NONE;
997 
998 	/*
999 	 * Don't consider values that don't match min_height and min_width
1000 	 * constraints.
1001 	 */
1002 	if (info->min_width || info->min_height)
1003 		for (i = 0; i < n_win_sizes; i++) {
1004 			wsize = info->devtype->win_sizes + i;
1005 
1006 			if (wsize->width < info->min_width ||
1007 				wsize->height < info->min_height) {
1008 				win_sizes_limit = i;
1009 				break;
1010 			}
1011 		}
1012 	/*
1013 	 * Round requested image size down to the nearest
1014 	 * we support, but not below the smallest.
1015 	 */
1016 	for (wsize = info->devtype->win_sizes;
1017 	     wsize < info->devtype->win_sizes + win_sizes_limit; wsize++)
1018 		if (fmt->width >= wsize->width && fmt->height >= wsize->height)
1019 			break;
1020 	if (wsize >= info->devtype->win_sizes + win_sizes_limit)
1021 		wsize--;   /* Take the smallest one */
1022 	if (ret_wsize != NULL)
1023 		*ret_wsize = wsize;
1024 	/*
1025 	 * Note the size we'll actually handle.
1026 	 */
1027 	fmt->width = wsize->width;
1028 	fmt->height = wsize->height;
1029 	fmt->colorspace = ov7670_formats[index].colorspace;
1030 
1031 	info->format = *fmt;
1032 
1033 	return 0;
1034 }
1035 
1036 static int ov7670_apply_fmt(struct v4l2_subdev *sd)
1037 {
1038 	struct ov7670_info *info = to_state(sd);
1039 	struct ov7670_win_size *wsize = info->wsize;
1040 	unsigned char com7, com10 = 0;
1041 	int ret;
1042 
1043 	/*
1044 	 * COM7 is a pain in the ass, it doesn't like to be read then
1045 	 * quickly written afterward.  But we have everything we need
1046 	 * to set it absolutely here, as long as the format-specific
1047 	 * register sets list it first.
1048 	 */
1049 	com7 = info->fmt->regs[0].value;
1050 	com7 |= wsize->com7_bit;
1051 	ret = ov7670_write(sd, REG_COM7, com7);
1052 	if (ret)
1053 		return ret;
1054 
1055 	/*
1056 	 * Configure the media bus through COM10 register
1057 	 */
1058 	if (info->mbus_config & V4L2_MBUS_VSYNC_ACTIVE_LOW)
1059 		com10 |= COM10_VS_NEG;
1060 	if (info->mbus_config & V4L2_MBUS_HSYNC_ACTIVE_LOW)
1061 		com10 |= COM10_HREF_REV;
1062 	if (info->pclk_hb_disable)
1063 		com10 |= COM10_PCLK_HB;
1064 	ret = ov7670_write(sd, REG_COM10, com10);
1065 	if (ret)
1066 		return ret;
1067 
1068 	/*
1069 	 * Now write the rest of the array.  Also store start/stops
1070 	 */
1071 	ret = ov7670_write_array(sd, info->fmt->regs + 1);
1072 	if (ret)
1073 		return ret;
1074 
1075 	ret = ov7670_set_hw(sd, wsize->hstart, wsize->hstop, wsize->vstart,
1076 			    wsize->vstop);
1077 	if (ret)
1078 		return ret;
1079 
1080 	if (wsize->regs) {
1081 		ret = ov7670_write_array(sd, wsize->regs);
1082 		if (ret)
1083 			return ret;
1084 	}
1085 
1086 	/*
1087 	 * If we're running RGB565, we must rewrite clkrc after setting
1088 	 * the other parameters or the image looks poor.  If we're *not*
1089 	 * doing RGB565, we must not rewrite clkrc or the image looks
1090 	 * *really* poor.
1091 	 *
1092 	 * (Update) Now that we retain clkrc state, we should be able
1093 	 * to write it unconditionally, and that will make the frame
1094 	 * rate persistent too.
1095 	 */
1096 	ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
1097 	if (ret)
1098 		return ret;
1099 
1100 	return 0;
1101 }
1102 
1103 /*
1104  * Set a format.
1105  */
1106 static int ov7670_set_fmt(struct v4l2_subdev *sd,
1107 		struct v4l2_subdev_state *sd_state,
1108 		struct v4l2_subdev_format *format)
1109 {
1110 	struct ov7670_info *info = to_state(sd);
1111 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1112 	struct v4l2_mbus_framefmt *mbus_fmt;
1113 #endif
1114 	int ret;
1115 
1116 	if (format->pad)
1117 		return -EINVAL;
1118 
1119 	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
1120 		ret = ov7670_try_fmt_internal(sd, &format->format, NULL, NULL);
1121 		if (ret)
1122 			return ret;
1123 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1124 		mbus_fmt = v4l2_subdev_get_try_format(sd, sd_state,
1125 						      format->pad);
1126 		*mbus_fmt = format->format;
1127 #endif
1128 		return 0;
1129 	}
1130 
1131 	ret = ov7670_try_fmt_internal(sd, &format->format, &info->fmt, &info->wsize);
1132 	if (ret)
1133 		return ret;
1134 
1135 	/*
1136 	 * If the device is not powered up by the host driver do
1137 	 * not apply any changes to H/W at this time. Instead
1138 	 * the frame format will be restored right after power-up.
1139 	 */
1140 	if (info->on)
1141 		return ov7670_apply_fmt(sd);
1142 
1143 	return 0;
1144 }
1145 
1146 static int ov7670_get_fmt(struct v4l2_subdev *sd,
1147 			  struct v4l2_subdev_state *sd_state,
1148 			  struct v4l2_subdev_format *format)
1149 {
1150 	struct ov7670_info *info = to_state(sd);
1151 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1152 	struct v4l2_mbus_framefmt *mbus_fmt;
1153 #endif
1154 
1155 	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
1156 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1157 		mbus_fmt = v4l2_subdev_get_try_format(sd, sd_state, 0);
1158 		format->format = *mbus_fmt;
1159 		return 0;
1160 #else
1161 		return -EINVAL;
1162 #endif
1163 	} else {
1164 		format->format = info->format;
1165 	}
1166 
1167 	return 0;
1168 }
1169 
1170 /*
1171  * Implement G/S_PARM.  There is a "high quality" mode we could try
1172  * to do someday; for now, we just do the frame rate tweak.
1173  */
1174 static int ov7670_g_frame_interval(struct v4l2_subdev *sd,
1175 				   struct v4l2_subdev_frame_interval *ival)
1176 {
1177 	struct ov7670_info *info = to_state(sd);
1178 
1179 
1180 	info->devtype->get_framerate(sd, &ival->interval);
1181 
1182 	return 0;
1183 }
1184 
1185 static int ov7670_s_frame_interval(struct v4l2_subdev *sd,
1186 				   struct v4l2_subdev_frame_interval *ival)
1187 {
1188 	struct v4l2_fract *tpf = &ival->interval;
1189 	struct ov7670_info *info = to_state(sd);
1190 
1191 
1192 	return info->devtype->set_framerate(sd, tpf);
1193 }
1194 
1195 
1196 /*
1197  * Frame intervals.  Since frame rates are controlled with the clock
1198  * divider, we can only do 30/n for integer n values.  So no continuous
1199  * or stepwise options.  Here we just pick a handful of logical values.
1200  */
1201 
1202 static int ov7670_frame_rates[] = { 30, 15, 10, 5, 1 };
1203 
1204 static int ov7670_enum_frame_interval(struct v4l2_subdev *sd,
1205 				      struct v4l2_subdev_state *sd_state,
1206 				      struct v4l2_subdev_frame_interval_enum *fie)
1207 {
1208 	struct ov7670_info *info = to_state(sd);
1209 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
1210 	int i;
1211 
1212 	if (fie->pad)
1213 		return -EINVAL;
1214 	if (fie->index >= ARRAY_SIZE(ov7670_frame_rates))
1215 		return -EINVAL;
1216 
1217 	/*
1218 	 * Check if the width/height is valid.
1219 	 *
1220 	 * If a minimum width/height was requested, filter out the capture
1221 	 * windows that fall outside that.
1222 	 */
1223 	for (i = 0; i < n_win_sizes; i++) {
1224 		struct ov7670_win_size *win = &info->devtype->win_sizes[i];
1225 
1226 		if (info->min_width && win->width < info->min_width)
1227 			continue;
1228 		if (info->min_height && win->height < info->min_height)
1229 			continue;
1230 		if (fie->width == win->width && fie->height == win->height)
1231 			break;
1232 	}
1233 	if (i == n_win_sizes)
1234 		return -EINVAL;
1235 	fie->interval.numerator = 1;
1236 	fie->interval.denominator = ov7670_frame_rates[fie->index];
1237 	return 0;
1238 }
1239 
1240 /*
1241  * Frame size enumeration
1242  */
1243 static int ov7670_enum_frame_size(struct v4l2_subdev *sd,
1244 				  struct v4l2_subdev_state *sd_state,
1245 				  struct v4l2_subdev_frame_size_enum *fse)
1246 {
1247 	struct ov7670_info *info = to_state(sd);
1248 	int i;
1249 	int num_valid = -1;
1250 	__u32 index = fse->index;
1251 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
1252 
1253 	if (fse->pad)
1254 		return -EINVAL;
1255 
1256 	/*
1257 	 * If a minimum width/height was requested, filter out the capture
1258 	 * windows that fall outside that.
1259 	 */
1260 	for (i = 0; i < n_win_sizes; i++) {
1261 		struct ov7670_win_size *win = &info->devtype->win_sizes[i];
1262 
1263 		if (info->min_width && win->width < info->min_width)
1264 			continue;
1265 		if (info->min_height && win->height < info->min_height)
1266 			continue;
1267 		if (index == ++num_valid) {
1268 			fse->min_width = fse->max_width = win->width;
1269 			fse->min_height = fse->max_height = win->height;
1270 			return 0;
1271 		}
1272 	}
1273 
1274 	return -EINVAL;
1275 }
1276 
1277 /*
1278  * Code for dealing with controls.
1279  */
1280 
1281 static int ov7670_store_cmatrix(struct v4l2_subdev *sd,
1282 		int matrix[CMATRIX_LEN])
1283 {
1284 	int i, ret;
1285 	unsigned char signbits = 0;
1286 
1287 	/*
1288 	 * Weird crap seems to exist in the upper part of
1289 	 * the sign bits register, so let's preserve it.
1290 	 */
1291 	ret = ov7670_read(sd, REG_CMATRIX_SIGN, &signbits);
1292 	signbits &= 0xc0;
1293 
1294 	for (i = 0; i < CMATRIX_LEN; i++) {
1295 		unsigned char raw;
1296 
1297 		if (matrix[i] < 0) {
1298 			signbits |= (1 << i);
1299 			if (matrix[i] < -255)
1300 				raw = 0xff;
1301 			else
1302 				raw = (-1 * matrix[i]) & 0xff;
1303 		} else {
1304 			if (matrix[i] > 255)
1305 				raw = 0xff;
1306 			else
1307 				raw = matrix[i] & 0xff;
1308 		}
1309 		ret = ov7670_write(sd, REG_CMATRIX_BASE + i, raw);
1310 		if (ret)
1311 			return ret;
1312 	}
1313 	return ov7670_write(sd, REG_CMATRIX_SIGN, signbits);
1314 }
1315 
1316 
1317 /*
1318  * Hue also requires messing with the color matrix.  It also requires
1319  * trig functions, which tend not to be well supported in the kernel.
1320  * So here is a simple table of sine values, 0-90 degrees, in steps
1321  * of five degrees.  Values are multiplied by 1000.
1322  *
1323  * The following naive approximate trig functions require an argument
1324  * carefully limited to -180 <= theta <= 180.
1325  */
1326 #define SIN_STEP 5
1327 static const int ov7670_sin_table[] = {
1328 	   0,	 87,   173,   258,   342,   422,
1329 	 499,	573,   642,   707,   766,   819,
1330 	 866,	906,   939,   965,   984,   996,
1331 	1000
1332 };
1333 
1334 static int ov7670_sine(int theta)
1335 {
1336 	int chs = 1;
1337 	int sine;
1338 
1339 	if (theta < 0) {
1340 		theta = -theta;
1341 		chs = -1;
1342 	}
1343 	if (theta <= 90)
1344 		sine = ov7670_sin_table[theta/SIN_STEP];
1345 	else {
1346 		theta -= 90;
1347 		sine = 1000 - ov7670_sin_table[theta/SIN_STEP];
1348 	}
1349 	return sine*chs;
1350 }
1351 
1352 static int ov7670_cosine(int theta)
1353 {
1354 	theta = 90 - theta;
1355 	if (theta > 180)
1356 		theta -= 360;
1357 	else if (theta < -180)
1358 		theta += 360;
1359 	return ov7670_sine(theta);
1360 }
1361 
1362 
1363 
1364 
1365 static void ov7670_calc_cmatrix(struct ov7670_info *info,
1366 		int matrix[CMATRIX_LEN], int sat, int hue)
1367 {
1368 	int i;
1369 	/*
1370 	 * Apply the current saturation setting first.
1371 	 */
1372 	for (i = 0; i < CMATRIX_LEN; i++)
1373 		matrix[i] = (info->fmt->cmatrix[i] * sat) >> 7;
1374 	/*
1375 	 * Then, if need be, rotate the hue value.
1376 	 */
1377 	if (hue != 0) {
1378 		int sinth, costh, tmpmatrix[CMATRIX_LEN];
1379 
1380 		memcpy(tmpmatrix, matrix, CMATRIX_LEN*sizeof(int));
1381 		sinth = ov7670_sine(hue);
1382 		costh = ov7670_cosine(hue);
1383 
1384 		matrix[0] = (matrix[3]*sinth + matrix[0]*costh)/1000;
1385 		matrix[1] = (matrix[4]*sinth + matrix[1]*costh)/1000;
1386 		matrix[2] = (matrix[5]*sinth + matrix[2]*costh)/1000;
1387 		matrix[3] = (matrix[3]*costh - matrix[0]*sinth)/1000;
1388 		matrix[4] = (matrix[4]*costh - matrix[1]*sinth)/1000;
1389 		matrix[5] = (matrix[5]*costh - matrix[2]*sinth)/1000;
1390 	}
1391 }
1392 
1393 
1394 
1395 static int ov7670_s_sat_hue(struct v4l2_subdev *sd, int sat, int hue)
1396 {
1397 	struct ov7670_info *info = to_state(sd);
1398 	int matrix[CMATRIX_LEN];
1399 
1400 	ov7670_calc_cmatrix(info, matrix, sat, hue);
1401 	return ov7670_store_cmatrix(sd, matrix);
1402 }
1403 
1404 
1405 /*
1406  * Some weird registers seem to store values in a sign/magnitude format!
1407  */
1408 
1409 static unsigned char ov7670_abs_to_sm(unsigned char v)
1410 {
1411 	if (v > 127)
1412 		return v & 0x7f;
1413 	return (128 - v) | 0x80;
1414 }
1415 
1416 static int ov7670_s_brightness(struct v4l2_subdev *sd, int value)
1417 {
1418 	unsigned char com8 = 0, v;
1419 
1420 	ov7670_read(sd, REG_COM8, &com8);
1421 	com8 &= ~COM8_AEC;
1422 	ov7670_write(sd, REG_COM8, com8);
1423 	v = ov7670_abs_to_sm(value);
1424 	return ov7670_write(sd, REG_BRIGHT, v);
1425 }
1426 
1427 static int ov7670_s_contrast(struct v4l2_subdev *sd, int value)
1428 {
1429 	return ov7670_write(sd, REG_CONTRAS, (unsigned char) value);
1430 }
1431 
1432 static int ov7670_s_hflip(struct v4l2_subdev *sd, int value)
1433 {
1434 	unsigned char v = 0;
1435 	int ret;
1436 
1437 	ret = ov7670_read(sd, REG_MVFP, &v);
1438 	if (ret)
1439 		return ret;
1440 	if (value)
1441 		v |= MVFP_MIRROR;
1442 	else
1443 		v &= ~MVFP_MIRROR;
1444 	msleep(10);  /* FIXME */
1445 	return ov7670_write(sd, REG_MVFP, v);
1446 }
1447 
1448 static int ov7670_s_vflip(struct v4l2_subdev *sd, int value)
1449 {
1450 	unsigned char v = 0;
1451 	int ret;
1452 
1453 	ret = ov7670_read(sd, REG_MVFP, &v);
1454 	if (ret)
1455 		return ret;
1456 	if (value)
1457 		v |= MVFP_FLIP;
1458 	else
1459 		v &= ~MVFP_FLIP;
1460 	msleep(10);  /* FIXME */
1461 	return ov7670_write(sd, REG_MVFP, v);
1462 }
1463 
1464 /*
1465  * GAIN is split between REG_GAIN and REG_VREF[7:6].  If one believes
1466  * the data sheet, the VREF parts should be the most significant, but
1467  * experience shows otherwise.  There seems to be little value in
1468  * messing with the VREF bits, so we leave them alone.
1469  */
1470 static int ov7670_g_gain(struct v4l2_subdev *sd, __s32 *value)
1471 {
1472 	int ret;
1473 	unsigned char gain;
1474 
1475 	ret = ov7670_read(sd, REG_GAIN, &gain);
1476 	if (ret)
1477 		return ret;
1478 	*value = gain;
1479 	return 0;
1480 }
1481 
1482 static int ov7670_s_gain(struct v4l2_subdev *sd, int value)
1483 {
1484 	int ret;
1485 	unsigned char com8;
1486 
1487 	ret = ov7670_write(sd, REG_GAIN, value & 0xff);
1488 	if (ret)
1489 		return ret;
1490 	/* Have to turn off AGC as well */
1491 	ret = ov7670_read(sd, REG_COM8, &com8);
1492 	if (ret)
1493 		return ret;
1494 	return ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
1495 }
1496 
1497 /*
1498  * Tweak autogain.
1499  */
1500 static int ov7670_s_autogain(struct v4l2_subdev *sd, int value)
1501 {
1502 	int ret;
1503 	unsigned char com8;
1504 
1505 	ret = ov7670_read(sd, REG_COM8, &com8);
1506 	if (ret == 0) {
1507 		if (value)
1508 			com8 |= COM8_AGC;
1509 		else
1510 			com8 &= ~COM8_AGC;
1511 		ret = ov7670_write(sd, REG_COM8, com8);
1512 	}
1513 	return ret;
1514 }
1515 
1516 static int ov7670_s_exp(struct v4l2_subdev *sd, int value)
1517 {
1518 	int ret;
1519 	unsigned char com1, com8, aech, aechh;
1520 
1521 	ret = ov7670_read(sd, REG_COM1, &com1) +
1522 		ov7670_read(sd, REG_COM8, &com8) +
1523 		ov7670_read(sd, REG_AECHH, &aechh);
1524 	if (ret)
1525 		return ret;
1526 
1527 	com1 = (com1 & 0xfc) | (value & 0x03);
1528 	aech = (value >> 2) & 0xff;
1529 	aechh = (aechh & 0xc0) | ((value >> 10) & 0x3f);
1530 	ret = ov7670_write(sd, REG_COM1, com1) +
1531 		ov7670_write(sd, REG_AECH, aech) +
1532 		ov7670_write(sd, REG_AECHH, aechh);
1533 	/* Have to turn off AEC as well */
1534 	if (ret == 0)
1535 		ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AEC);
1536 	return ret;
1537 }
1538 
1539 /*
1540  * Tweak autoexposure.
1541  */
1542 static int ov7670_s_autoexp(struct v4l2_subdev *sd,
1543 		enum v4l2_exposure_auto_type value)
1544 {
1545 	int ret;
1546 	unsigned char com8;
1547 
1548 	ret = ov7670_read(sd, REG_COM8, &com8);
1549 	if (ret == 0) {
1550 		if (value == V4L2_EXPOSURE_AUTO)
1551 			com8 |= COM8_AEC;
1552 		else
1553 			com8 &= ~COM8_AEC;
1554 		ret = ov7670_write(sd, REG_COM8, com8);
1555 	}
1556 	return ret;
1557 }
1558 
1559 static const char * const ov7670_test_pattern_menu[] = {
1560 	"No test output",
1561 	"Shifting \"1\"",
1562 	"8-bar color bar",
1563 	"Fade to gray color bar",
1564 };
1565 
1566 static int ov7670_s_test_pattern(struct v4l2_subdev *sd, int value)
1567 {
1568 	int ret;
1569 
1570 	ret = ov7670_update_bits(sd, REG_SCALING_XSC, TEST_PATTTERN_0,
1571 				value & BIT(0) ? TEST_PATTTERN_0 : 0);
1572 	if (ret)
1573 		return ret;
1574 
1575 	return ov7670_update_bits(sd, REG_SCALING_YSC, TEST_PATTTERN_1,
1576 				value & BIT(1) ? TEST_PATTTERN_1 : 0);
1577 }
1578 
1579 static int ov7670_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
1580 {
1581 	struct v4l2_subdev *sd = to_sd(ctrl);
1582 	struct ov7670_info *info = to_state(sd);
1583 
1584 	switch (ctrl->id) {
1585 	case V4L2_CID_AUTOGAIN:
1586 		return ov7670_g_gain(sd, &info->gain->val);
1587 	}
1588 	return -EINVAL;
1589 }
1590 
1591 static int ov7670_s_ctrl(struct v4l2_ctrl *ctrl)
1592 {
1593 	struct v4l2_subdev *sd = to_sd(ctrl);
1594 	struct ov7670_info *info = to_state(sd);
1595 
1596 	switch (ctrl->id) {
1597 	case V4L2_CID_BRIGHTNESS:
1598 		return ov7670_s_brightness(sd, ctrl->val);
1599 	case V4L2_CID_CONTRAST:
1600 		return ov7670_s_contrast(sd, ctrl->val);
1601 	case V4L2_CID_SATURATION:
1602 		return ov7670_s_sat_hue(sd,
1603 				info->saturation->val, info->hue->val);
1604 	case V4L2_CID_VFLIP:
1605 		return ov7670_s_vflip(sd, ctrl->val);
1606 	case V4L2_CID_HFLIP:
1607 		return ov7670_s_hflip(sd, ctrl->val);
1608 	case V4L2_CID_AUTOGAIN:
1609 		/* Only set manual gain if auto gain is not explicitly
1610 		   turned on. */
1611 		if (!ctrl->val) {
1612 			/* ov7670_s_gain turns off auto gain */
1613 			return ov7670_s_gain(sd, info->gain->val);
1614 		}
1615 		return ov7670_s_autogain(sd, ctrl->val);
1616 	case V4L2_CID_EXPOSURE_AUTO:
1617 		/* Only set manual exposure if auto exposure is not explicitly
1618 		   turned on. */
1619 		if (ctrl->val == V4L2_EXPOSURE_MANUAL) {
1620 			/* ov7670_s_exp turns off auto exposure */
1621 			return ov7670_s_exp(sd, info->exposure->val);
1622 		}
1623 		return ov7670_s_autoexp(sd, ctrl->val);
1624 	case V4L2_CID_TEST_PATTERN:
1625 		return ov7670_s_test_pattern(sd, ctrl->val);
1626 	}
1627 	return -EINVAL;
1628 }
1629 
1630 static const struct v4l2_ctrl_ops ov7670_ctrl_ops = {
1631 	.s_ctrl = ov7670_s_ctrl,
1632 	.g_volatile_ctrl = ov7670_g_volatile_ctrl,
1633 };
1634 
1635 #ifdef CONFIG_VIDEO_ADV_DEBUG
1636 static int ov7670_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
1637 {
1638 	unsigned char val = 0;
1639 	int ret;
1640 
1641 	ret = ov7670_read(sd, reg->reg & 0xff, &val);
1642 	reg->val = val;
1643 	reg->size = 1;
1644 	return ret;
1645 }
1646 
1647 static int ov7670_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
1648 {
1649 	ov7670_write(sd, reg->reg & 0xff, reg->val & 0xff);
1650 	return 0;
1651 }
1652 #endif
1653 
1654 static void ov7670_power_on(struct v4l2_subdev *sd)
1655 {
1656 	struct ov7670_info *info = to_state(sd);
1657 
1658 	if (info->on)
1659 		return;
1660 
1661 	clk_prepare_enable(info->clk);
1662 
1663 	if (info->pwdn_gpio)
1664 		gpiod_set_value(info->pwdn_gpio, 0);
1665 	if (info->resetb_gpio) {
1666 		gpiod_set_value(info->resetb_gpio, 1);
1667 		usleep_range(500, 1000);
1668 		gpiod_set_value(info->resetb_gpio, 0);
1669 	}
1670 	if (info->pwdn_gpio || info->resetb_gpio || info->clk)
1671 		usleep_range(3000, 5000);
1672 
1673 	info->on = true;
1674 }
1675 
1676 static void ov7670_power_off(struct v4l2_subdev *sd)
1677 {
1678 	struct ov7670_info *info = to_state(sd);
1679 
1680 	if (!info->on)
1681 		return;
1682 
1683 	clk_disable_unprepare(info->clk);
1684 
1685 	if (info->pwdn_gpio)
1686 		gpiod_set_value(info->pwdn_gpio, 1);
1687 
1688 	info->on = false;
1689 }
1690 
1691 static int ov7670_s_power(struct v4l2_subdev *sd, int on)
1692 {
1693 	struct ov7670_info *info = to_state(sd);
1694 
1695 	if (info->on == on)
1696 		return 0;
1697 
1698 	if (on) {
1699 		ov7670_power_on(sd);
1700 		ov7670_init(sd, 0);
1701 		ov7670_apply_fmt(sd);
1702 		ov7675_apply_framerate(sd);
1703 		v4l2_ctrl_handler_setup(&info->hdl);
1704 	} else {
1705 		ov7670_power_off(sd);
1706 	}
1707 
1708 	return 0;
1709 }
1710 
1711 static void ov7670_get_default_format(struct v4l2_subdev *sd,
1712 				      struct v4l2_mbus_framefmt *format)
1713 {
1714 	struct ov7670_info *info = to_state(sd);
1715 
1716 	format->width = info->devtype->win_sizes[0].width;
1717 	format->height = info->devtype->win_sizes[0].height;
1718 	format->colorspace = info->fmt->colorspace;
1719 	format->code = info->fmt->mbus_code;
1720 	format->field = V4L2_FIELD_NONE;
1721 }
1722 
1723 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1724 static int ov7670_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
1725 {
1726 	struct v4l2_mbus_framefmt *format =
1727 				v4l2_subdev_get_try_format(sd, fh->state, 0);
1728 
1729 	ov7670_get_default_format(sd, format);
1730 
1731 	return 0;
1732 }
1733 #endif
1734 
1735 /* ----------------------------------------------------------------------- */
1736 
1737 static const struct v4l2_subdev_core_ops ov7670_core_ops = {
1738 	.reset = ov7670_reset,
1739 	.init = ov7670_init,
1740 	.s_power = ov7670_s_power,
1741 	.log_status = v4l2_ctrl_subdev_log_status,
1742 	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
1743 	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
1744 #ifdef CONFIG_VIDEO_ADV_DEBUG
1745 	.g_register = ov7670_g_register,
1746 	.s_register = ov7670_s_register,
1747 #endif
1748 };
1749 
1750 static const struct v4l2_subdev_video_ops ov7670_video_ops = {
1751 	.s_frame_interval = ov7670_s_frame_interval,
1752 	.g_frame_interval = ov7670_g_frame_interval,
1753 };
1754 
1755 static const struct v4l2_subdev_pad_ops ov7670_pad_ops = {
1756 	.enum_frame_interval = ov7670_enum_frame_interval,
1757 	.enum_frame_size = ov7670_enum_frame_size,
1758 	.enum_mbus_code = ov7670_enum_mbus_code,
1759 	.get_fmt = ov7670_get_fmt,
1760 	.set_fmt = ov7670_set_fmt,
1761 };
1762 
1763 static const struct v4l2_subdev_ops ov7670_ops = {
1764 	.core = &ov7670_core_ops,
1765 	.video = &ov7670_video_ops,
1766 	.pad = &ov7670_pad_ops,
1767 };
1768 
1769 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1770 static const struct v4l2_subdev_internal_ops ov7670_subdev_internal_ops = {
1771 	.open = ov7670_open,
1772 };
1773 #endif
1774 
1775 /* ----------------------------------------------------------------------- */
1776 
1777 static const struct ov7670_devtype ov7670_devdata[] = {
1778 	[MODEL_OV7670] = {
1779 		.win_sizes = ov7670_win_sizes,
1780 		.n_win_sizes = ARRAY_SIZE(ov7670_win_sizes),
1781 		.set_framerate = ov7670_set_framerate_legacy,
1782 		.get_framerate = ov7670_get_framerate_legacy,
1783 	},
1784 	[MODEL_OV7675] = {
1785 		.win_sizes = ov7675_win_sizes,
1786 		.n_win_sizes = ARRAY_SIZE(ov7675_win_sizes),
1787 		.set_framerate = ov7675_set_framerate,
1788 		.get_framerate = ov7675_get_framerate,
1789 	},
1790 };
1791 
1792 static int ov7670_init_gpio(struct i2c_client *client, struct ov7670_info *info)
1793 {
1794 	info->pwdn_gpio = devm_gpiod_get_optional(&client->dev, "powerdown",
1795 			GPIOD_OUT_LOW);
1796 	if (IS_ERR(info->pwdn_gpio)) {
1797 		dev_info(&client->dev, "can't get %s GPIO\n", "powerdown");
1798 		return PTR_ERR(info->pwdn_gpio);
1799 	}
1800 
1801 	info->resetb_gpio = devm_gpiod_get_optional(&client->dev, "reset",
1802 			GPIOD_OUT_LOW);
1803 	if (IS_ERR(info->resetb_gpio)) {
1804 		dev_info(&client->dev, "can't get %s GPIO\n", "reset");
1805 		return PTR_ERR(info->resetb_gpio);
1806 	}
1807 
1808 	usleep_range(3000, 5000);
1809 
1810 	return 0;
1811 }
1812 
1813 /*
1814  * ov7670_parse_dt() - Parse device tree to collect mbus configuration
1815  *			properties
1816  */
1817 static int ov7670_parse_dt(struct device *dev,
1818 			   struct ov7670_info *info)
1819 {
1820 	struct fwnode_handle *fwnode = dev_fwnode(dev);
1821 	struct v4l2_fwnode_endpoint bus_cfg = { .bus_type = 0 };
1822 	struct fwnode_handle *ep;
1823 	int ret;
1824 
1825 	if (!fwnode)
1826 		return -EINVAL;
1827 
1828 	info->pclk_hb_disable = false;
1829 	if (fwnode_property_present(fwnode, "ov7670,pclk-hb-disable"))
1830 		info->pclk_hb_disable = true;
1831 
1832 	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
1833 	if (!ep)
1834 		return -EINVAL;
1835 
1836 	ret = v4l2_fwnode_endpoint_parse(ep, &bus_cfg);
1837 	fwnode_handle_put(ep);
1838 	if (ret)
1839 		return ret;
1840 
1841 	if (bus_cfg.bus_type != V4L2_MBUS_PARALLEL) {
1842 		dev_err(dev, "Unsupported media bus type\n");
1843 		return -EINVAL;
1844 	}
1845 	info->mbus_config = bus_cfg.bus.parallel.flags;
1846 
1847 	return 0;
1848 }
1849 
1850 static int ov7670_probe(struct i2c_client *client)
1851 {
1852 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
1853 	struct v4l2_fract tpf;
1854 	struct v4l2_subdev *sd;
1855 	struct ov7670_info *info;
1856 	int ret;
1857 
1858 	info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
1859 	if (info == NULL)
1860 		return -ENOMEM;
1861 	sd = &info->sd;
1862 	v4l2_i2c_subdev_init(sd, client, &ov7670_ops);
1863 
1864 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1865 	sd->internal_ops = &ov7670_subdev_internal_ops;
1866 	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
1867 #endif
1868 
1869 	info->clock_speed = 30; /* default: a guess */
1870 
1871 	if (dev_fwnode(&client->dev)) {
1872 		ret = ov7670_parse_dt(&client->dev, info);
1873 		if (ret)
1874 			return ret;
1875 
1876 	} else if (client->dev.platform_data) {
1877 		struct ov7670_config *config = client->dev.platform_data;
1878 
1879 		/*
1880 		 * Must apply configuration before initializing device, because it
1881 		 * selects I/O method.
1882 		 */
1883 		info->min_width = config->min_width;
1884 		info->min_height = config->min_height;
1885 		info->use_smbus = config->use_smbus;
1886 
1887 		if (config->clock_speed)
1888 			info->clock_speed = config->clock_speed;
1889 
1890 		if (config->pll_bypass)
1891 			info->pll_bypass = true;
1892 
1893 		if (config->pclk_hb_disable)
1894 			info->pclk_hb_disable = true;
1895 	}
1896 
1897 	info->clk = devm_clk_get_optional(&client->dev, "xclk");
1898 	if (IS_ERR(info->clk))
1899 		return PTR_ERR(info->clk);
1900 
1901 	ret = ov7670_init_gpio(client, info);
1902 	if (ret)
1903 		return ret;
1904 
1905 	ov7670_power_on(sd);
1906 
1907 	if (info->clk) {
1908 		info->clock_speed = clk_get_rate(info->clk) / 1000000;
1909 		if (info->clock_speed < 10 || info->clock_speed > 48) {
1910 			ret = -EINVAL;
1911 			goto power_off;
1912 		}
1913 	}
1914 
1915 	/* Make sure it's an ov7670 */
1916 	ret = ov7670_detect(sd);
1917 	if (ret) {
1918 		v4l_dbg(1, debug, client,
1919 			"chip found @ 0x%x (%s) is not an ov7670 chip.\n",
1920 			client->addr << 1, client->adapter->name);
1921 		goto power_off;
1922 	}
1923 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
1924 			client->addr << 1, client->adapter->name);
1925 
1926 	info->devtype = &ov7670_devdata[id->driver_data];
1927 	info->fmt = &ov7670_formats[0];
1928 	info->wsize = &info->devtype->win_sizes[0];
1929 
1930 	ov7670_get_default_format(sd, &info->format);
1931 
1932 	info->clkrc = 0;
1933 
1934 	/* Set default frame rate to 30 fps */
1935 	tpf.numerator = 1;
1936 	tpf.denominator = 30;
1937 	info->devtype->set_framerate(sd, &tpf);
1938 
1939 	v4l2_ctrl_handler_init(&info->hdl, 10);
1940 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1941 			V4L2_CID_BRIGHTNESS, 0, 255, 1, 128);
1942 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1943 			V4L2_CID_CONTRAST, 0, 127, 1, 64);
1944 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1945 			V4L2_CID_VFLIP, 0, 1, 1, 0);
1946 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1947 			V4L2_CID_HFLIP, 0, 1, 1, 0);
1948 	info->saturation = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1949 			V4L2_CID_SATURATION, 0, 256, 1, 128);
1950 	info->hue = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1951 			V4L2_CID_HUE, -180, 180, 5, 0);
1952 	info->gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1953 			V4L2_CID_GAIN, 0, 255, 1, 128);
1954 	info->auto_gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1955 			V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
1956 	info->exposure = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1957 			V4L2_CID_EXPOSURE, 0, 65535, 1, 500);
1958 	info->auto_exposure = v4l2_ctrl_new_std_menu(&info->hdl, &ov7670_ctrl_ops,
1959 			V4L2_CID_EXPOSURE_AUTO, V4L2_EXPOSURE_MANUAL, 0,
1960 			V4L2_EXPOSURE_AUTO);
1961 	v4l2_ctrl_new_std_menu_items(&info->hdl, &ov7670_ctrl_ops,
1962 			V4L2_CID_TEST_PATTERN,
1963 			ARRAY_SIZE(ov7670_test_pattern_menu) - 1, 0, 0,
1964 			ov7670_test_pattern_menu);
1965 	sd->ctrl_handler = &info->hdl;
1966 	if (info->hdl.error) {
1967 		ret = info->hdl.error;
1968 
1969 		goto hdl_free;
1970 	}
1971 	/*
1972 	 * We have checked empirically that hw allows to read back the gain
1973 	 * value chosen by auto gain but that's not the case for auto exposure.
1974 	 */
1975 	v4l2_ctrl_auto_cluster(2, &info->auto_gain, 0, true);
1976 	v4l2_ctrl_auto_cluster(2, &info->auto_exposure,
1977 			       V4L2_EXPOSURE_MANUAL, false);
1978 	v4l2_ctrl_cluster(2, &info->saturation);
1979 
1980 #if defined(CONFIG_MEDIA_CONTROLLER)
1981 	info->pad.flags = MEDIA_PAD_FL_SOURCE;
1982 	info->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
1983 	ret = media_entity_pads_init(&info->sd.entity, 1, &info->pad);
1984 	if (ret < 0)
1985 		goto hdl_free;
1986 #endif
1987 
1988 	v4l2_ctrl_handler_setup(&info->hdl);
1989 
1990 	ret = v4l2_async_register_subdev(&info->sd);
1991 	if (ret < 0)
1992 		goto entity_cleanup;
1993 
1994 	ov7670_power_off(sd);
1995 	return 0;
1996 
1997 entity_cleanup:
1998 	media_entity_cleanup(&info->sd.entity);
1999 hdl_free:
2000 	v4l2_ctrl_handler_free(&info->hdl);
2001 power_off:
2002 	ov7670_power_off(sd);
2003 	return ret;
2004 }
2005 
2006 static void ov7670_remove(struct i2c_client *client)
2007 {
2008 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
2009 	struct ov7670_info *info = to_state(sd);
2010 
2011 	v4l2_async_unregister_subdev(sd);
2012 	v4l2_ctrl_handler_free(&info->hdl);
2013 	media_entity_cleanup(&info->sd.entity);
2014 }
2015 
2016 static const struct i2c_device_id ov7670_id[] = {
2017 	{ "ov7670", MODEL_OV7670 },
2018 	{ "ov7675", MODEL_OV7675 },
2019 	{ }
2020 };
2021 MODULE_DEVICE_TABLE(i2c, ov7670_id);
2022 
2023 #if IS_ENABLED(CONFIG_OF)
2024 static const struct of_device_id ov7670_of_match[] = {
2025 	{ .compatible = "ovti,ov7670", },
2026 	{ /* sentinel */ },
2027 };
2028 MODULE_DEVICE_TABLE(of, ov7670_of_match);
2029 #endif
2030 
2031 static struct i2c_driver ov7670_driver = {
2032 	.driver = {
2033 		.name	= "ov7670",
2034 		.of_match_table = of_match_ptr(ov7670_of_match),
2035 	},
2036 	.probe		= ov7670_probe,
2037 	.remove		= ov7670_remove,
2038 	.id_table	= ov7670_id,
2039 };
2040 
2041 module_i2c_driver(ov7670_driver);
2042