xref: /openbmc/linux/drivers/media/i2c/ov7670.c (revision 7a010c3c)
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 
565 	if (info->use_smbus)
566 		return ov7670_read_smbus(sd, reg, value);
567 	else
568 		return ov7670_read_i2c(sd, reg, value);
569 }
570 
571 static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
572 		unsigned char value)
573 {
574 	struct ov7670_info *info = to_state(sd);
575 
576 	if (info->use_smbus)
577 		return ov7670_write_smbus(sd, reg, value);
578 	else
579 		return ov7670_write_i2c(sd, reg, value);
580 }
581 
582 static int ov7670_update_bits(struct v4l2_subdev *sd, unsigned char reg,
583 		unsigned char mask, unsigned char value)
584 {
585 	unsigned char orig;
586 	int ret;
587 
588 	ret = ov7670_read(sd, reg, &orig);
589 	if (ret)
590 		return ret;
591 
592 	return ov7670_write(sd, reg, (orig & ~mask) | (value & mask));
593 }
594 
595 /*
596  * Write a list of register settings; ff/ff stops the process.
597  */
598 static int ov7670_write_array(struct v4l2_subdev *sd, struct regval_list *vals)
599 {
600 	while (vals->reg_num != 0xff || vals->value != 0xff) {
601 		int ret = ov7670_write(sd, vals->reg_num, vals->value);
602 
603 		if (ret < 0)
604 			return ret;
605 		vals++;
606 	}
607 	return 0;
608 }
609 
610 
611 /*
612  * Stuff that knows about the sensor.
613  */
614 static int ov7670_reset(struct v4l2_subdev *sd, u32 val)
615 {
616 	ov7670_write(sd, REG_COM7, COM7_RESET);
617 	msleep(1);
618 	return 0;
619 }
620 
621 
622 static int ov7670_init(struct v4l2_subdev *sd, u32 val)
623 {
624 	return ov7670_write_array(sd, ov7670_default_regs);
625 }
626 
627 static int ov7670_detect(struct v4l2_subdev *sd)
628 {
629 	unsigned char v;
630 	int ret;
631 
632 	ret = ov7670_init(sd, 0);
633 	if (ret < 0)
634 		return ret;
635 	ret = ov7670_read(sd, REG_MIDH, &v);
636 	if (ret < 0)
637 		return ret;
638 	if (v != 0x7f) /* OV manuf. id. */
639 		return -ENODEV;
640 	ret = ov7670_read(sd, REG_MIDL, &v);
641 	if (ret < 0)
642 		return ret;
643 	if (v != 0xa2)
644 		return -ENODEV;
645 	/*
646 	 * OK, we know we have an OmniVision chip...but which one?
647 	 */
648 	ret = ov7670_read(sd, REG_PID, &v);
649 	if (ret < 0)
650 		return ret;
651 	if (v != 0x76)  /* PID + VER = 0x76 / 0x73 */
652 		return -ENODEV;
653 	ret = ov7670_read(sd, REG_VER, &v);
654 	if (ret < 0)
655 		return ret;
656 	if (v != 0x73)  /* PID + VER = 0x76 / 0x73 */
657 		return -ENODEV;
658 	return 0;
659 }
660 
661 
662 /*
663  * Store information about the video data format.  The color matrix
664  * is deeply tied into the format, so keep the relevant values here.
665  * The magic matrix numbers come from OmniVision.
666  */
667 static struct ov7670_format_struct {
668 	u32 mbus_code;
669 	enum v4l2_colorspace colorspace;
670 	struct regval_list *regs;
671 	int cmatrix[CMATRIX_LEN];
672 } ov7670_formats[] = {
673 	{
674 		.mbus_code	= MEDIA_BUS_FMT_YUYV8_2X8,
675 		.colorspace	= V4L2_COLORSPACE_SRGB,
676 		.regs		= ov7670_fmt_yuv422,
677 		.cmatrix	= { 128, -128, 0, -34, -94, 128 },
678 	},
679 	{
680 		.mbus_code	= MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE,
681 		.colorspace	= V4L2_COLORSPACE_SRGB,
682 		.regs		= ov7670_fmt_rgb444,
683 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
684 	},
685 	{
686 		.mbus_code	= MEDIA_BUS_FMT_RGB565_2X8_LE,
687 		.colorspace	= V4L2_COLORSPACE_SRGB,
688 		.regs		= ov7670_fmt_rgb565,
689 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
690 	},
691 	{
692 		.mbus_code	= MEDIA_BUS_FMT_SBGGR8_1X8,
693 		.colorspace	= V4L2_COLORSPACE_SRGB,
694 		.regs		= ov7670_fmt_raw,
695 		.cmatrix	= { 0, 0, 0, 0, 0, 0 },
696 	},
697 };
698 #define N_OV7670_FMTS ARRAY_SIZE(ov7670_formats)
699 
700 
701 /*
702  * Then there is the issue of window sizes.  Try to capture the info here.
703  */
704 
705 /*
706  * QCIF mode is done (by OV) in a very strange way - it actually looks like
707  * VGA with weird scaling options - they do *not* use the canned QCIF mode
708  * which is allegedly provided by the sensor.  So here's the weird register
709  * settings.
710  */
711 static struct regval_list ov7670_qcif_regs[] = {
712 	{ REG_COM3, COM3_SCALEEN|COM3_DCWEN },
713 	{ REG_COM3, COM3_DCWEN },
714 	{ REG_COM14, COM14_DCWEN | 0x01},
715 	{ 0x73, 0xf1 },
716 	{ 0xa2, 0x52 },
717 	{ 0x7b, 0x1c },
718 	{ 0x7c, 0x28 },
719 	{ 0x7d, 0x3c },
720 	{ 0x7f, 0x69 },
721 	{ REG_COM9, 0x38 },
722 	{ 0xa1, 0x0b },
723 	{ 0x74, 0x19 },
724 	{ 0x9a, 0x80 },
725 	{ 0x43, 0x14 },
726 	{ REG_COM13, 0xc0 },
727 	{ 0xff, 0xff },
728 };
729 
730 static struct ov7670_win_size ov7670_win_sizes[] = {
731 	/* VGA */
732 	{
733 		.width		= VGA_WIDTH,
734 		.height		= VGA_HEIGHT,
735 		.com7_bit	= COM7_FMT_VGA,
736 		.hstart		= 158,	/* These values from */
737 		.hstop		=  14,	/* Omnivision */
738 		.vstart		=  10,
739 		.vstop		= 490,
740 		.regs		= NULL,
741 	},
742 	/* CIF */
743 	{
744 		.width		= CIF_WIDTH,
745 		.height		= CIF_HEIGHT,
746 		.com7_bit	= COM7_FMT_CIF,
747 		.hstart		= 170,	/* Empirically determined */
748 		.hstop		=  90,
749 		.vstart		=  14,
750 		.vstop		= 494,
751 		.regs		= NULL,
752 	},
753 	/* QVGA */
754 	{
755 		.width		= QVGA_WIDTH,
756 		.height		= QVGA_HEIGHT,
757 		.com7_bit	= COM7_FMT_QVGA,
758 		.hstart		= 168,	/* Empirically determined */
759 		.hstop		=  24,
760 		.vstart		=  12,
761 		.vstop		= 492,
762 		.regs		= NULL,
763 	},
764 	/* QCIF */
765 	{
766 		.width		= QCIF_WIDTH,
767 		.height		= QCIF_HEIGHT,
768 		.com7_bit	= COM7_FMT_VGA, /* see comment above */
769 		.hstart		= 456,	/* Empirically determined */
770 		.hstop		=  24,
771 		.vstart		=  14,
772 		.vstop		= 494,
773 		.regs		= ov7670_qcif_regs,
774 	}
775 };
776 
777 static struct ov7670_win_size ov7675_win_sizes[] = {
778 	/*
779 	 * Currently, only VGA is supported. Theoretically it could be possible
780 	 * to support CIF, QVGA and QCIF too. Taking values for ov7670 as a
781 	 * base and tweak them empirically could be required.
782 	 */
783 	{
784 		.width		= VGA_WIDTH,
785 		.height		= VGA_HEIGHT,
786 		.com7_bit	= COM7_FMT_VGA,
787 		.hstart		= 158,	/* These values from */
788 		.hstop		=  14,	/* Omnivision */
789 		.vstart		=  14,  /* Empirically determined */
790 		.vstop		= 494,
791 		.regs		= NULL,
792 	}
793 };
794 
795 static void ov7675_get_framerate(struct v4l2_subdev *sd,
796 				 struct v4l2_fract *tpf)
797 {
798 	struct ov7670_info *info = to_state(sd);
799 	u32 clkrc = info->clkrc;
800 	int pll_factor;
801 
802 	if (info->pll_bypass)
803 		pll_factor = 1;
804 	else
805 		pll_factor = PLL_FACTOR;
806 
807 	clkrc++;
808 	if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
809 		clkrc = (clkrc >> 1);
810 
811 	tpf->numerator = 1;
812 	tpf->denominator = (5 * pll_factor * info->clock_speed) /
813 			(4 * clkrc);
814 }
815 
816 static int ov7675_apply_framerate(struct v4l2_subdev *sd)
817 {
818 	struct ov7670_info *info = to_state(sd);
819 	int ret;
820 
821 	ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
822 	if (ret < 0)
823 		return ret;
824 
825 	return ov7670_write(sd, REG_DBLV,
826 			    info->pll_bypass ? DBLV_BYPASS : DBLV_X4);
827 }
828 
829 static int ov7675_set_framerate(struct v4l2_subdev *sd,
830 				 struct v4l2_fract *tpf)
831 {
832 	struct ov7670_info *info = to_state(sd);
833 	u32 clkrc;
834 	int pll_factor;
835 
836 	/*
837 	 * The formula is fps = 5/4*pixclk for YUV/RGB and
838 	 * fps = 5/2*pixclk for RAW.
839 	 *
840 	 * pixclk = clock_speed / (clkrc + 1) * PLLfactor
841 	 *
842 	 */
843 	if (tpf->numerator == 0 || tpf->denominator == 0) {
844 		clkrc = 0;
845 	} else {
846 		pll_factor = info->pll_bypass ? 1 : PLL_FACTOR;
847 		clkrc = (5 * pll_factor * info->clock_speed * tpf->numerator) /
848 			(4 * tpf->denominator);
849 		if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
850 			clkrc = (clkrc << 1);
851 		clkrc--;
852 	}
853 
854 	/*
855 	 * The datasheet claims that clkrc = 0 will divide the input clock by 1
856 	 * but we've checked with an oscilloscope that it divides by 2 instead.
857 	 * So, if clkrc = 0 just bypass the divider.
858 	 */
859 	if (clkrc <= 0)
860 		clkrc = CLK_EXT;
861 	else if (clkrc > CLK_SCALE)
862 		clkrc = CLK_SCALE;
863 	info->clkrc = clkrc;
864 
865 	/* Recalculate frame rate */
866 	ov7675_get_framerate(sd, tpf);
867 
868 	/*
869 	 * If the device is not powered up by the host driver do
870 	 * not apply any changes to H/W at this time. Instead
871 	 * the framerate will be restored right after power-up.
872 	 */
873 	if (info->on)
874 		return ov7675_apply_framerate(sd);
875 
876 	return 0;
877 }
878 
879 static void ov7670_get_framerate_legacy(struct v4l2_subdev *sd,
880 				 struct v4l2_fract *tpf)
881 {
882 	struct ov7670_info *info = to_state(sd);
883 
884 	tpf->numerator = 1;
885 	tpf->denominator = info->clock_speed;
886 	if ((info->clkrc & CLK_EXT) == 0 && (info->clkrc & CLK_SCALE) > 1)
887 		tpf->denominator /= (info->clkrc & CLK_SCALE);
888 }
889 
890 static int ov7670_set_framerate_legacy(struct v4l2_subdev *sd,
891 					struct v4l2_fract *tpf)
892 {
893 	struct ov7670_info *info = to_state(sd);
894 	int div;
895 
896 	if (tpf->numerator == 0 || tpf->denominator == 0)
897 		div = 1;  /* Reset to full rate */
898 	else
899 		div = (tpf->numerator * info->clock_speed) / tpf->denominator;
900 	if (div == 0)
901 		div = 1;
902 	else if (div > CLK_SCALE)
903 		div = CLK_SCALE;
904 	info->clkrc = (info->clkrc & 0x80) | div;
905 	tpf->numerator = 1;
906 	tpf->denominator = info->clock_speed / div;
907 
908 	/*
909 	 * If the device is not powered up by the host driver do
910 	 * not apply any changes to H/W at this time. Instead
911 	 * the framerate will be restored right after power-up.
912 	 */
913 	if (info->on)
914 		return ov7670_write(sd, REG_CLKRC, info->clkrc);
915 
916 	return 0;
917 }
918 
919 /*
920  * Store a set of start/stop values into the camera.
921  */
922 static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop,
923 		int vstart, int vstop)
924 {
925 	int ret;
926 	unsigned char v;
927 	/*
928 	 * Horizontal: 11 bits, top 8 live in hstart and hstop.  Bottom 3 of
929 	 * hstart are in href[2:0], bottom 3 of hstop in href[5:3].  There is
930 	 * a mystery "edge offset" value in the top two bits of href.
931 	 */
932 	ret = ov7670_write(sd, REG_HSTART, (hstart >> 3) & 0xff);
933 	if (ret)
934 		return ret;
935 	ret = ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff);
936 	if (ret)
937 		return ret;
938 	ret = ov7670_read(sd, REG_HREF, &v);
939 	if (ret)
940 		return ret;
941 	v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7);
942 	msleep(10);
943 	ret = ov7670_write(sd, REG_HREF, v);
944 	if (ret)
945 		return ret;
946 	/* Vertical: similar arrangement, but only 10 bits. */
947 	ret = ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff);
948 	if (ret)
949 		return ret;
950 	ret = ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff);
951 	if (ret)
952 		return ret;
953 	ret = ov7670_read(sd, REG_VREF, &v);
954 	if (ret)
955 		return ret;
956 	v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3);
957 	msleep(10);
958 	return ov7670_write(sd, REG_VREF, v);
959 }
960 
961 
962 static int ov7670_enum_mbus_code(struct v4l2_subdev *sd,
963 		struct v4l2_subdev_state *sd_state,
964 		struct v4l2_subdev_mbus_code_enum *code)
965 {
966 	if (code->pad || code->index >= N_OV7670_FMTS)
967 		return -EINVAL;
968 
969 	code->code = ov7670_formats[code->index].mbus_code;
970 	return 0;
971 }
972 
973 static int ov7670_try_fmt_internal(struct v4l2_subdev *sd,
974 		struct v4l2_mbus_framefmt *fmt,
975 		struct ov7670_format_struct **ret_fmt,
976 		struct ov7670_win_size **ret_wsize)
977 {
978 	int index, i;
979 	struct ov7670_win_size *wsize;
980 	struct ov7670_info *info = to_state(sd);
981 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
982 	unsigned int win_sizes_limit = n_win_sizes;
983 
984 	for (index = 0; index < N_OV7670_FMTS; index++)
985 		if (ov7670_formats[index].mbus_code == fmt->code)
986 			break;
987 	if (index >= N_OV7670_FMTS) {
988 		/* default to first format */
989 		index = 0;
990 		fmt->code = ov7670_formats[0].mbus_code;
991 	}
992 	if (ret_fmt != NULL)
993 		*ret_fmt = ov7670_formats + index;
994 	/*
995 	 * Fields: the OV devices claim to be progressive.
996 	 */
997 	fmt->field = V4L2_FIELD_NONE;
998 
999 	/*
1000 	 * Don't consider values that don't match min_height and min_width
1001 	 * constraints.
1002 	 */
1003 	if (info->min_width || info->min_height)
1004 		for (i = 0; i < n_win_sizes; i++) {
1005 			wsize = info->devtype->win_sizes + i;
1006 
1007 			if (wsize->width < info->min_width ||
1008 				wsize->height < info->min_height) {
1009 				win_sizes_limit = i;
1010 				break;
1011 			}
1012 		}
1013 	/*
1014 	 * Round requested image size down to the nearest
1015 	 * we support, but not below the smallest.
1016 	 */
1017 	for (wsize = info->devtype->win_sizes;
1018 	     wsize < info->devtype->win_sizes + win_sizes_limit; wsize++)
1019 		if (fmt->width >= wsize->width && fmt->height >= wsize->height)
1020 			break;
1021 	if (wsize >= info->devtype->win_sizes + win_sizes_limit)
1022 		wsize--;   /* Take the smallest one */
1023 	if (ret_wsize != NULL)
1024 		*ret_wsize = wsize;
1025 	/*
1026 	 * Note the size we'll actually handle.
1027 	 */
1028 	fmt->width = wsize->width;
1029 	fmt->height = wsize->height;
1030 	fmt->colorspace = ov7670_formats[index].colorspace;
1031 
1032 	info->format = *fmt;
1033 
1034 	return 0;
1035 }
1036 
1037 static int ov7670_apply_fmt(struct v4l2_subdev *sd)
1038 {
1039 	struct ov7670_info *info = to_state(sd);
1040 	struct ov7670_win_size *wsize = info->wsize;
1041 	unsigned char com7, com10 = 0;
1042 	int ret;
1043 
1044 	/*
1045 	 * COM7 is a pain in the ass, it doesn't like to be read then
1046 	 * quickly written afterward.  But we have everything we need
1047 	 * to set it absolutely here, as long as the format-specific
1048 	 * register sets list it first.
1049 	 */
1050 	com7 = info->fmt->regs[0].value;
1051 	com7 |= wsize->com7_bit;
1052 	ret = ov7670_write(sd, REG_COM7, com7);
1053 	if (ret)
1054 		return ret;
1055 
1056 	/*
1057 	 * Configure the media bus through COM10 register
1058 	 */
1059 	if (info->mbus_config & V4L2_MBUS_VSYNC_ACTIVE_LOW)
1060 		com10 |= COM10_VS_NEG;
1061 	if (info->mbus_config & V4L2_MBUS_HSYNC_ACTIVE_LOW)
1062 		com10 |= COM10_HREF_REV;
1063 	if (info->pclk_hb_disable)
1064 		com10 |= COM10_PCLK_HB;
1065 	ret = ov7670_write(sd, REG_COM10, com10);
1066 	if (ret)
1067 		return ret;
1068 
1069 	/*
1070 	 * Now write the rest of the array.  Also store start/stops
1071 	 */
1072 	ret = ov7670_write_array(sd, info->fmt->regs + 1);
1073 	if (ret)
1074 		return ret;
1075 
1076 	ret = ov7670_set_hw(sd, wsize->hstart, wsize->hstop, wsize->vstart,
1077 			    wsize->vstop);
1078 	if (ret)
1079 		return ret;
1080 
1081 	if (wsize->regs) {
1082 		ret = ov7670_write_array(sd, wsize->regs);
1083 		if (ret)
1084 			return ret;
1085 	}
1086 
1087 	/*
1088 	 * If we're running RGB565, we must rewrite clkrc after setting
1089 	 * the other parameters or the image looks poor.  If we're *not*
1090 	 * doing RGB565, we must not rewrite clkrc or the image looks
1091 	 * *really* poor.
1092 	 *
1093 	 * (Update) Now that we retain clkrc state, we should be able
1094 	 * to write it unconditionally, and that will make the frame
1095 	 * rate persistent too.
1096 	 */
1097 	ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
1098 	if (ret)
1099 		return ret;
1100 
1101 	return 0;
1102 }
1103 
1104 /*
1105  * Set a format.
1106  */
1107 static int ov7670_set_fmt(struct v4l2_subdev *sd,
1108 		struct v4l2_subdev_state *sd_state,
1109 		struct v4l2_subdev_format *format)
1110 {
1111 	struct ov7670_info *info = to_state(sd);
1112 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1113 	struct v4l2_mbus_framefmt *mbus_fmt;
1114 #endif
1115 	int ret;
1116 
1117 	if (format->pad)
1118 		return -EINVAL;
1119 
1120 	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
1121 		ret = ov7670_try_fmt_internal(sd, &format->format, NULL, NULL);
1122 		if (ret)
1123 			return ret;
1124 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1125 		mbus_fmt = v4l2_subdev_get_try_format(sd, sd_state,
1126 						      format->pad);
1127 		*mbus_fmt = format->format;
1128 #endif
1129 		return 0;
1130 	}
1131 
1132 	ret = ov7670_try_fmt_internal(sd, &format->format, &info->fmt, &info->wsize);
1133 	if (ret)
1134 		return ret;
1135 
1136 	/*
1137 	 * If the device is not powered up by the host driver do
1138 	 * not apply any changes to H/W at this time. Instead
1139 	 * the frame format will be restored right after power-up.
1140 	 */
1141 	if (info->on)
1142 		return ov7670_apply_fmt(sd);
1143 
1144 	return 0;
1145 }
1146 
1147 static int ov7670_get_fmt(struct v4l2_subdev *sd,
1148 			  struct v4l2_subdev_state *sd_state,
1149 			  struct v4l2_subdev_format *format)
1150 {
1151 	struct ov7670_info *info = to_state(sd);
1152 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1153 	struct v4l2_mbus_framefmt *mbus_fmt;
1154 #endif
1155 
1156 	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
1157 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1158 		mbus_fmt = v4l2_subdev_get_try_format(sd, sd_state, 0);
1159 		format->format = *mbus_fmt;
1160 		return 0;
1161 #else
1162 		return -EINVAL;
1163 #endif
1164 	} else {
1165 		format->format = info->format;
1166 	}
1167 
1168 	return 0;
1169 }
1170 
1171 /*
1172  * Implement G/S_PARM.  There is a "high quality" mode we could try
1173  * to do someday; for now, we just do the frame rate tweak.
1174  */
1175 static int ov7670_g_frame_interval(struct v4l2_subdev *sd,
1176 				   struct v4l2_subdev_frame_interval *ival)
1177 {
1178 	struct ov7670_info *info = to_state(sd);
1179 
1180 
1181 	info->devtype->get_framerate(sd, &ival->interval);
1182 
1183 	return 0;
1184 }
1185 
1186 static int ov7670_s_frame_interval(struct v4l2_subdev *sd,
1187 				   struct v4l2_subdev_frame_interval *ival)
1188 {
1189 	struct v4l2_fract *tpf = &ival->interval;
1190 	struct ov7670_info *info = to_state(sd);
1191 
1192 
1193 	return info->devtype->set_framerate(sd, tpf);
1194 }
1195 
1196 
1197 /*
1198  * Frame intervals.  Since frame rates are controlled with the clock
1199  * divider, we can only do 30/n for integer n values.  So no continuous
1200  * or stepwise options.  Here we just pick a handful of logical values.
1201  */
1202 
1203 static int ov7670_frame_rates[] = { 30, 15, 10, 5, 1 };
1204 
1205 static int ov7670_enum_frame_interval(struct v4l2_subdev *sd,
1206 				      struct v4l2_subdev_state *sd_state,
1207 				      struct v4l2_subdev_frame_interval_enum *fie)
1208 {
1209 	struct ov7670_info *info = to_state(sd);
1210 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
1211 	int i;
1212 
1213 	if (fie->pad)
1214 		return -EINVAL;
1215 	if (fie->index >= ARRAY_SIZE(ov7670_frame_rates))
1216 		return -EINVAL;
1217 
1218 	/*
1219 	 * Check if the width/height is valid.
1220 	 *
1221 	 * If a minimum width/height was requested, filter out the capture
1222 	 * windows that fall outside that.
1223 	 */
1224 	for (i = 0; i < n_win_sizes; i++) {
1225 		struct ov7670_win_size *win = &info->devtype->win_sizes[i];
1226 
1227 		if (info->min_width && win->width < info->min_width)
1228 			continue;
1229 		if (info->min_height && win->height < info->min_height)
1230 			continue;
1231 		if (fie->width == win->width && fie->height == win->height)
1232 			break;
1233 	}
1234 	if (i == n_win_sizes)
1235 		return -EINVAL;
1236 	fie->interval.numerator = 1;
1237 	fie->interval.denominator = ov7670_frame_rates[fie->index];
1238 	return 0;
1239 }
1240 
1241 /*
1242  * Frame size enumeration
1243  */
1244 static int ov7670_enum_frame_size(struct v4l2_subdev *sd,
1245 				  struct v4l2_subdev_state *sd_state,
1246 				  struct v4l2_subdev_frame_size_enum *fse)
1247 {
1248 	struct ov7670_info *info = to_state(sd);
1249 	int i;
1250 	int num_valid = -1;
1251 	__u32 index = fse->index;
1252 	unsigned int n_win_sizes = info->devtype->n_win_sizes;
1253 
1254 	if (fse->pad)
1255 		return -EINVAL;
1256 
1257 	/*
1258 	 * If a minimum width/height was requested, filter out the capture
1259 	 * windows that fall outside that.
1260 	 */
1261 	for (i = 0; i < n_win_sizes; i++) {
1262 		struct ov7670_win_size *win = &info->devtype->win_sizes[i];
1263 
1264 		if (info->min_width && win->width < info->min_width)
1265 			continue;
1266 		if (info->min_height && win->height < info->min_height)
1267 			continue;
1268 		if (index == ++num_valid) {
1269 			fse->min_width = fse->max_width = win->width;
1270 			fse->min_height = fse->max_height = win->height;
1271 			return 0;
1272 		}
1273 	}
1274 
1275 	return -EINVAL;
1276 }
1277 
1278 /*
1279  * Code for dealing with controls.
1280  */
1281 
1282 static int ov7670_store_cmatrix(struct v4l2_subdev *sd,
1283 		int matrix[CMATRIX_LEN])
1284 {
1285 	int i, ret;
1286 	unsigned char signbits = 0;
1287 
1288 	/*
1289 	 * Weird crap seems to exist in the upper part of
1290 	 * the sign bits register, so let's preserve it.
1291 	 */
1292 	ret = ov7670_read(sd, REG_CMATRIX_SIGN, &signbits);
1293 	signbits &= 0xc0;
1294 
1295 	for (i = 0; i < CMATRIX_LEN; i++) {
1296 		unsigned char raw;
1297 
1298 		if (matrix[i] < 0) {
1299 			signbits |= (1 << i);
1300 			if (matrix[i] < -255)
1301 				raw = 0xff;
1302 			else
1303 				raw = (-1 * matrix[i]) & 0xff;
1304 		} else {
1305 			if (matrix[i] > 255)
1306 				raw = 0xff;
1307 			else
1308 				raw = matrix[i] & 0xff;
1309 		}
1310 		ret = ov7670_write(sd, REG_CMATRIX_BASE + i, raw);
1311 		if (ret)
1312 			return ret;
1313 	}
1314 	return ov7670_write(sd, REG_CMATRIX_SIGN, signbits);
1315 }
1316 
1317 
1318 /*
1319  * Hue also requires messing with the color matrix.  It also requires
1320  * trig functions, which tend not to be well supported in the kernel.
1321  * So here is a simple table of sine values, 0-90 degrees, in steps
1322  * of five degrees.  Values are multiplied by 1000.
1323  *
1324  * The following naive approximate trig functions require an argument
1325  * carefully limited to -180 <= theta <= 180.
1326  */
1327 #define SIN_STEP 5
1328 static const int ov7670_sin_table[] = {
1329 	   0,	 87,   173,   258,   342,   422,
1330 	 499,	573,   642,   707,   766,   819,
1331 	 866,	906,   939,   965,   984,   996,
1332 	1000
1333 };
1334 
1335 static int ov7670_sine(int theta)
1336 {
1337 	int chs = 1;
1338 	int sine;
1339 
1340 	if (theta < 0) {
1341 		theta = -theta;
1342 		chs = -1;
1343 	}
1344 	if (theta <= 90)
1345 		sine = ov7670_sin_table[theta/SIN_STEP];
1346 	else {
1347 		theta -= 90;
1348 		sine = 1000 - ov7670_sin_table[theta/SIN_STEP];
1349 	}
1350 	return sine*chs;
1351 }
1352 
1353 static int ov7670_cosine(int theta)
1354 {
1355 	theta = 90 - theta;
1356 	if (theta > 180)
1357 		theta -= 360;
1358 	else if (theta < -180)
1359 		theta += 360;
1360 	return ov7670_sine(theta);
1361 }
1362 
1363 
1364 
1365 
1366 static void ov7670_calc_cmatrix(struct ov7670_info *info,
1367 		int matrix[CMATRIX_LEN], int sat, int hue)
1368 {
1369 	int i;
1370 	/*
1371 	 * Apply the current saturation setting first.
1372 	 */
1373 	for (i = 0; i < CMATRIX_LEN; i++)
1374 		matrix[i] = (info->fmt->cmatrix[i] * sat) >> 7;
1375 	/*
1376 	 * Then, if need be, rotate the hue value.
1377 	 */
1378 	if (hue != 0) {
1379 		int sinth, costh, tmpmatrix[CMATRIX_LEN];
1380 
1381 		memcpy(tmpmatrix, matrix, CMATRIX_LEN*sizeof(int));
1382 		sinth = ov7670_sine(hue);
1383 		costh = ov7670_cosine(hue);
1384 
1385 		matrix[0] = (matrix[3]*sinth + matrix[0]*costh)/1000;
1386 		matrix[1] = (matrix[4]*sinth + matrix[1]*costh)/1000;
1387 		matrix[2] = (matrix[5]*sinth + matrix[2]*costh)/1000;
1388 		matrix[3] = (matrix[3]*costh - matrix[0]*sinth)/1000;
1389 		matrix[4] = (matrix[4]*costh - matrix[1]*sinth)/1000;
1390 		matrix[5] = (matrix[5]*costh - matrix[2]*sinth)/1000;
1391 	}
1392 }
1393 
1394 
1395 
1396 static int ov7670_s_sat_hue(struct v4l2_subdev *sd, int sat, int hue)
1397 {
1398 	struct ov7670_info *info = to_state(sd);
1399 	int matrix[CMATRIX_LEN];
1400 
1401 	ov7670_calc_cmatrix(info, matrix, sat, hue);
1402 	return ov7670_store_cmatrix(sd, matrix);
1403 }
1404 
1405 
1406 /*
1407  * Some weird registers seem to store values in a sign/magnitude format!
1408  */
1409 
1410 static unsigned char ov7670_abs_to_sm(unsigned char v)
1411 {
1412 	if (v > 127)
1413 		return v & 0x7f;
1414 	return (128 - v) | 0x80;
1415 }
1416 
1417 static int ov7670_s_brightness(struct v4l2_subdev *sd, int value)
1418 {
1419 	unsigned char com8 = 0, v;
1420 
1421 	ov7670_read(sd, REG_COM8, &com8);
1422 	com8 &= ~COM8_AEC;
1423 	ov7670_write(sd, REG_COM8, com8);
1424 	v = ov7670_abs_to_sm(value);
1425 	return ov7670_write(sd, REG_BRIGHT, v);
1426 }
1427 
1428 static int ov7670_s_contrast(struct v4l2_subdev *sd, int value)
1429 {
1430 	return ov7670_write(sd, REG_CONTRAS, (unsigned char) value);
1431 }
1432 
1433 static int ov7670_s_hflip(struct v4l2_subdev *sd, int value)
1434 {
1435 	unsigned char v = 0;
1436 	int ret;
1437 
1438 	ret = ov7670_read(sd, REG_MVFP, &v);
1439 	if (ret)
1440 		return ret;
1441 	if (value)
1442 		v |= MVFP_MIRROR;
1443 	else
1444 		v &= ~MVFP_MIRROR;
1445 	msleep(10);  /* FIXME */
1446 	return ov7670_write(sd, REG_MVFP, v);
1447 }
1448 
1449 static int ov7670_s_vflip(struct v4l2_subdev *sd, int value)
1450 {
1451 	unsigned char v = 0;
1452 	int ret;
1453 
1454 	ret = ov7670_read(sd, REG_MVFP, &v);
1455 	if (ret)
1456 		return ret;
1457 	if (value)
1458 		v |= MVFP_FLIP;
1459 	else
1460 		v &= ~MVFP_FLIP;
1461 	msleep(10);  /* FIXME */
1462 	return ov7670_write(sd, REG_MVFP, v);
1463 }
1464 
1465 /*
1466  * GAIN is split between REG_GAIN and REG_VREF[7:6].  If one believes
1467  * the data sheet, the VREF parts should be the most significant, but
1468  * experience shows otherwise.  There seems to be little value in
1469  * messing with the VREF bits, so we leave them alone.
1470  */
1471 static int ov7670_g_gain(struct v4l2_subdev *sd, __s32 *value)
1472 {
1473 	int ret;
1474 	unsigned char gain;
1475 
1476 	ret = ov7670_read(sd, REG_GAIN, &gain);
1477 	if (ret)
1478 		return ret;
1479 	*value = gain;
1480 	return 0;
1481 }
1482 
1483 static int ov7670_s_gain(struct v4l2_subdev *sd, int value)
1484 {
1485 	int ret;
1486 	unsigned char com8;
1487 
1488 	ret = ov7670_write(sd, REG_GAIN, value & 0xff);
1489 	if (ret)
1490 		return ret;
1491 	/* Have to turn off AGC as well */
1492 	ret = ov7670_read(sd, REG_COM8, &com8);
1493 	if (ret)
1494 		return ret;
1495 	return ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
1496 }
1497 
1498 /*
1499  * Tweak autogain.
1500  */
1501 static int ov7670_s_autogain(struct v4l2_subdev *sd, int value)
1502 {
1503 	int ret;
1504 	unsigned char com8;
1505 
1506 	ret = ov7670_read(sd, REG_COM8, &com8);
1507 	if (ret == 0) {
1508 		if (value)
1509 			com8 |= COM8_AGC;
1510 		else
1511 			com8 &= ~COM8_AGC;
1512 		ret = ov7670_write(sd, REG_COM8, com8);
1513 	}
1514 	return ret;
1515 }
1516 
1517 static int ov7670_s_exp(struct v4l2_subdev *sd, int value)
1518 {
1519 	int ret;
1520 	unsigned char com1, com8, aech, aechh;
1521 
1522 	ret = ov7670_read(sd, REG_COM1, &com1) +
1523 		ov7670_read(sd, REG_COM8, &com8) +
1524 		ov7670_read(sd, REG_AECHH, &aechh);
1525 	if (ret)
1526 		return ret;
1527 
1528 	com1 = (com1 & 0xfc) | (value & 0x03);
1529 	aech = (value >> 2) & 0xff;
1530 	aechh = (aechh & 0xc0) | ((value >> 10) & 0x3f);
1531 	ret = ov7670_write(sd, REG_COM1, com1) +
1532 		ov7670_write(sd, REG_AECH, aech) +
1533 		ov7670_write(sd, REG_AECHH, aechh);
1534 	/* Have to turn off AEC as well */
1535 	if (ret == 0)
1536 		ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AEC);
1537 	return ret;
1538 }
1539 
1540 /*
1541  * Tweak autoexposure.
1542  */
1543 static int ov7670_s_autoexp(struct v4l2_subdev *sd,
1544 		enum v4l2_exposure_auto_type value)
1545 {
1546 	int ret;
1547 	unsigned char com8;
1548 
1549 	ret = ov7670_read(sd, REG_COM8, &com8);
1550 	if (ret == 0) {
1551 		if (value == V4L2_EXPOSURE_AUTO)
1552 			com8 |= COM8_AEC;
1553 		else
1554 			com8 &= ~COM8_AEC;
1555 		ret = ov7670_write(sd, REG_COM8, com8);
1556 	}
1557 	return ret;
1558 }
1559 
1560 static const char * const ov7670_test_pattern_menu[] = {
1561 	"No test output",
1562 	"Shifting \"1\"",
1563 	"8-bar color bar",
1564 	"Fade to gray color bar",
1565 };
1566 
1567 static int ov7670_s_test_pattern(struct v4l2_subdev *sd, int value)
1568 {
1569 	int ret;
1570 
1571 	ret = ov7670_update_bits(sd, REG_SCALING_XSC, TEST_PATTTERN_0,
1572 				value & BIT(0) ? TEST_PATTTERN_0 : 0);
1573 	if (ret)
1574 		return ret;
1575 
1576 	return ov7670_update_bits(sd, REG_SCALING_YSC, TEST_PATTTERN_1,
1577 				value & BIT(1) ? TEST_PATTTERN_1 : 0);
1578 }
1579 
1580 static int ov7670_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
1581 {
1582 	struct v4l2_subdev *sd = to_sd(ctrl);
1583 	struct ov7670_info *info = to_state(sd);
1584 
1585 	switch (ctrl->id) {
1586 	case V4L2_CID_AUTOGAIN:
1587 		return ov7670_g_gain(sd, &info->gain->val);
1588 	}
1589 	return -EINVAL;
1590 }
1591 
1592 static int ov7670_s_ctrl(struct v4l2_ctrl *ctrl)
1593 {
1594 	struct v4l2_subdev *sd = to_sd(ctrl);
1595 	struct ov7670_info *info = to_state(sd);
1596 
1597 	switch (ctrl->id) {
1598 	case V4L2_CID_BRIGHTNESS:
1599 		return ov7670_s_brightness(sd, ctrl->val);
1600 	case V4L2_CID_CONTRAST:
1601 		return ov7670_s_contrast(sd, ctrl->val);
1602 	case V4L2_CID_SATURATION:
1603 		return ov7670_s_sat_hue(sd,
1604 				info->saturation->val, info->hue->val);
1605 	case V4L2_CID_VFLIP:
1606 		return ov7670_s_vflip(sd, ctrl->val);
1607 	case V4L2_CID_HFLIP:
1608 		return ov7670_s_hflip(sd, ctrl->val);
1609 	case V4L2_CID_AUTOGAIN:
1610 		/* Only set manual gain if auto gain is not explicitly
1611 		   turned on. */
1612 		if (!ctrl->val) {
1613 			/* ov7670_s_gain turns off auto gain */
1614 			return ov7670_s_gain(sd, info->gain->val);
1615 		}
1616 		return ov7670_s_autogain(sd, ctrl->val);
1617 	case V4L2_CID_EXPOSURE_AUTO:
1618 		/* Only set manual exposure if auto exposure is not explicitly
1619 		   turned on. */
1620 		if (ctrl->val == V4L2_EXPOSURE_MANUAL) {
1621 			/* ov7670_s_exp turns off auto exposure */
1622 			return ov7670_s_exp(sd, info->exposure->val);
1623 		}
1624 		return ov7670_s_autoexp(sd, ctrl->val);
1625 	case V4L2_CID_TEST_PATTERN:
1626 		return ov7670_s_test_pattern(sd, ctrl->val);
1627 	}
1628 	return -EINVAL;
1629 }
1630 
1631 static const struct v4l2_ctrl_ops ov7670_ctrl_ops = {
1632 	.s_ctrl = ov7670_s_ctrl,
1633 	.g_volatile_ctrl = ov7670_g_volatile_ctrl,
1634 };
1635 
1636 #ifdef CONFIG_VIDEO_ADV_DEBUG
1637 static int ov7670_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
1638 {
1639 	unsigned char val = 0;
1640 	int ret;
1641 
1642 	ret = ov7670_read(sd, reg->reg & 0xff, &val);
1643 	reg->val = val;
1644 	reg->size = 1;
1645 	return ret;
1646 }
1647 
1648 static int ov7670_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
1649 {
1650 	ov7670_write(sd, reg->reg & 0xff, reg->val & 0xff);
1651 	return 0;
1652 }
1653 #endif
1654 
1655 static void ov7670_power_on(struct v4l2_subdev *sd)
1656 {
1657 	struct ov7670_info *info = to_state(sd);
1658 
1659 	if (info->on)
1660 		return;
1661 
1662 	clk_prepare_enable(info->clk);
1663 
1664 	if (info->pwdn_gpio)
1665 		gpiod_set_value(info->pwdn_gpio, 0);
1666 	if (info->resetb_gpio) {
1667 		gpiod_set_value(info->resetb_gpio, 1);
1668 		usleep_range(500, 1000);
1669 		gpiod_set_value(info->resetb_gpio, 0);
1670 	}
1671 	if (info->pwdn_gpio || info->resetb_gpio || info->clk)
1672 		usleep_range(3000, 5000);
1673 
1674 	info->on = true;
1675 }
1676 
1677 static void ov7670_power_off(struct v4l2_subdev *sd)
1678 {
1679 	struct ov7670_info *info = to_state(sd);
1680 
1681 	if (!info->on)
1682 		return;
1683 
1684 	clk_disable_unprepare(info->clk);
1685 
1686 	if (info->pwdn_gpio)
1687 		gpiod_set_value(info->pwdn_gpio, 1);
1688 
1689 	info->on = false;
1690 }
1691 
1692 static int ov7670_s_power(struct v4l2_subdev *sd, int on)
1693 {
1694 	struct ov7670_info *info = to_state(sd);
1695 
1696 	if (info->on == on)
1697 		return 0;
1698 
1699 	if (on) {
1700 		ov7670_power_on(sd);
1701 		ov7670_init(sd, 0);
1702 		ov7670_apply_fmt(sd);
1703 		ov7675_apply_framerate(sd);
1704 		v4l2_ctrl_handler_setup(&info->hdl);
1705 	} else {
1706 		ov7670_power_off(sd);
1707 	}
1708 
1709 	return 0;
1710 }
1711 
1712 static void ov7670_get_default_format(struct v4l2_subdev *sd,
1713 				      struct v4l2_mbus_framefmt *format)
1714 {
1715 	struct ov7670_info *info = to_state(sd);
1716 
1717 	format->width = info->devtype->win_sizes[0].width;
1718 	format->height = info->devtype->win_sizes[0].height;
1719 	format->colorspace = info->fmt->colorspace;
1720 	format->code = info->fmt->mbus_code;
1721 	format->field = V4L2_FIELD_NONE;
1722 }
1723 
1724 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1725 static int ov7670_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
1726 {
1727 	struct v4l2_mbus_framefmt *format =
1728 				v4l2_subdev_get_try_format(sd, fh->state, 0);
1729 
1730 	ov7670_get_default_format(sd, format);
1731 
1732 	return 0;
1733 }
1734 #endif
1735 
1736 /* ----------------------------------------------------------------------- */
1737 
1738 static const struct v4l2_subdev_core_ops ov7670_core_ops = {
1739 	.reset = ov7670_reset,
1740 	.init = ov7670_init,
1741 	.s_power = ov7670_s_power,
1742 	.log_status = v4l2_ctrl_subdev_log_status,
1743 	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
1744 	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
1745 #ifdef CONFIG_VIDEO_ADV_DEBUG
1746 	.g_register = ov7670_g_register,
1747 	.s_register = ov7670_s_register,
1748 #endif
1749 };
1750 
1751 static const struct v4l2_subdev_video_ops ov7670_video_ops = {
1752 	.s_frame_interval = ov7670_s_frame_interval,
1753 	.g_frame_interval = ov7670_g_frame_interval,
1754 };
1755 
1756 static const struct v4l2_subdev_pad_ops ov7670_pad_ops = {
1757 	.enum_frame_interval = ov7670_enum_frame_interval,
1758 	.enum_frame_size = ov7670_enum_frame_size,
1759 	.enum_mbus_code = ov7670_enum_mbus_code,
1760 	.get_fmt = ov7670_get_fmt,
1761 	.set_fmt = ov7670_set_fmt,
1762 };
1763 
1764 static const struct v4l2_subdev_ops ov7670_ops = {
1765 	.core = &ov7670_core_ops,
1766 	.video = &ov7670_video_ops,
1767 	.pad = &ov7670_pad_ops,
1768 };
1769 
1770 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1771 static const struct v4l2_subdev_internal_ops ov7670_subdev_internal_ops = {
1772 	.open = ov7670_open,
1773 };
1774 #endif
1775 
1776 /* ----------------------------------------------------------------------- */
1777 
1778 static const struct ov7670_devtype ov7670_devdata[] = {
1779 	[MODEL_OV7670] = {
1780 		.win_sizes = ov7670_win_sizes,
1781 		.n_win_sizes = ARRAY_SIZE(ov7670_win_sizes),
1782 		.set_framerate = ov7670_set_framerate_legacy,
1783 		.get_framerate = ov7670_get_framerate_legacy,
1784 	},
1785 	[MODEL_OV7675] = {
1786 		.win_sizes = ov7675_win_sizes,
1787 		.n_win_sizes = ARRAY_SIZE(ov7675_win_sizes),
1788 		.set_framerate = ov7675_set_framerate,
1789 		.get_framerate = ov7675_get_framerate,
1790 	},
1791 };
1792 
1793 static int ov7670_init_gpio(struct i2c_client *client, struct ov7670_info *info)
1794 {
1795 	info->pwdn_gpio = devm_gpiod_get_optional(&client->dev, "powerdown",
1796 			GPIOD_OUT_LOW);
1797 	if (IS_ERR(info->pwdn_gpio)) {
1798 		dev_info(&client->dev, "can't get %s GPIO\n", "powerdown");
1799 		return PTR_ERR(info->pwdn_gpio);
1800 	}
1801 
1802 	info->resetb_gpio = devm_gpiod_get_optional(&client->dev, "reset",
1803 			GPIOD_OUT_LOW);
1804 	if (IS_ERR(info->resetb_gpio)) {
1805 		dev_info(&client->dev, "can't get %s GPIO\n", "reset");
1806 		return PTR_ERR(info->resetb_gpio);
1807 	}
1808 
1809 	usleep_range(3000, 5000);
1810 
1811 	return 0;
1812 }
1813 
1814 /*
1815  * ov7670_parse_dt() - Parse device tree to collect mbus configuration
1816  *			properties
1817  */
1818 static int ov7670_parse_dt(struct device *dev,
1819 			   struct ov7670_info *info)
1820 {
1821 	struct fwnode_handle *fwnode = dev_fwnode(dev);
1822 	struct v4l2_fwnode_endpoint bus_cfg = { .bus_type = 0 };
1823 	struct fwnode_handle *ep;
1824 	int ret;
1825 
1826 	if (!fwnode)
1827 		return -EINVAL;
1828 
1829 	info->pclk_hb_disable = false;
1830 	if (fwnode_property_present(fwnode, "ov7670,pclk-hb-disable"))
1831 		info->pclk_hb_disable = true;
1832 
1833 	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
1834 	if (!ep)
1835 		return -EINVAL;
1836 
1837 	ret = v4l2_fwnode_endpoint_parse(ep, &bus_cfg);
1838 	fwnode_handle_put(ep);
1839 	if (ret)
1840 		return ret;
1841 
1842 	if (bus_cfg.bus_type != V4L2_MBUS_PARALLEL) {
1843 		dev_err(dev, "Unsupported media bus type\n");
1844 		return ret;
1845 	}
1846 	info->mbus_config = bus_cfg.bus.parallel.flags;
1847 
1848 	return 0;
1849 }
1850 
1851 static int ov7670_probe(struct i2c_client *client,
1852 			const struct i2c_device_id *id)
1853 {
1854 	struct v4l2_fract tpf;
1855 	struct v4l2_subdev *sd;
1856 	struct ov7670_info *info;
1857 	int ret;
1858 
1859 	info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
1860 	if (info == NULL)
1861 		return -ENOMEM;
1862 	sd = &info->sd;
1863 	v4l2_i2c_subdev_init(sd, client, &ov7670_ops);
1864 
1865 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
1866 	sd->internal_ops = &ov7670_subdev_internal_ops;
1867 	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
1868 #endif
1869 
1870 	info->clock_speed = 30; /* default: a guess */
1871 
1872 	if (dev_fwnode(&client->dev)) {
1873 		ret = ov7670_parse_dt(&client->dev, info);
1874 		if (ret)
1875 			return ret;
1876 
1877 	} else if (client->dev.platform_data) {
1878 		struct ov7670_config *config = client->dev.platform_data;
1879 
1880 		/*
1881 		 * Must apply configuration before initializing device, because it
1882 		 * selects I/O method.
1883 		 */
1884 		info->min_width = config->min_width;
1885 		info->min_height = config->min_height;
1886 		info->use_smbus = config->use_smbus;
1887 
1888 		if (config->clock_speed)
1889 			info->clock_speed = config->clock_speed;
1890 
1891 		if (config->pll_bypass)
1892 			info->pll_bypass = true;
1893 
1894 		if (config->pclk_hb_disable)
1895 			info->pclk_hb_disable = true;
1896 	}
1897 
1898 	info->clk = devm_clk_get(&client->dev, "xclk"); /* optional */
1899 	if (IS_ERR(info->clk)) {
1900 		ret = PTR_ERR(info->clk);
1901 		if (ret == -ENOENT)
1902 			info->clk = NULL;
1903 		else
1904 			return ret;
1905 	}
1906 
1907 	ret = ov7670_init_gpio(client, info);
1908 	if (ret)
1909 		return ret;
1910 
1911 	ov7670_power_on(sd);
1912 
1913 	if (info->clk) {
1914 		info->clock_speed = clk_get_rate(info->clk) / 1000000;
1915 		if (info->clock_speed < 10 || info->clock_speed > 48) {
1916 			ret = -EINVAL;
1917 			goto power_off;
1918 		}
1919 	}
1920 
1921 	/* Make sure it's an ov7670 */
1922 	ret = ov7670_detect(sd);
1923 	if (ret) {
1924 		v4l_dbg(1, debug, client,
1925 			"chip found @ 0x%x (%s) is not an ov7670 chip.\n",
1926 			client->addr << 1, client->adapter->name);
1927 		goto power_off;
1928 	}
1929 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
1930 			client->addr << 1, client->adapter->name);
1931 
1932 	info->devtype = &ov7670_devdata[id->driver_data];
1933 	info->fmt = &ov7670_formats[0];
1934 	info->wsize = &info->devtype->win_sizes[0];
1935 
1936 	ov7670_get_default_format(sd, &info->format);
1937 
1938 	info->clkrc = 0;
1939 
1940 	/* Set default frame rate to 30 fps */
1941 	tpf.numerator = 1;
1942 	tpf.denominator = 30;
1943 	info->devtype->set_framerate(sd, &tpf);
1944 
1945 	v4l2_ctrl_handler_init(&info->hdl, 10);
1946 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1947 			V4L2_CID_BRIGHTNESS, 0, 255, 1, 128);
1948 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1949 			V4L2_CID_CONTRAST, 0, 127, 1, 64);
1950 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1951 			V4L2_CID_VFLIP, 0, 1, 1, 0);
1952 	v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1953 			V4L2_CID_HFLIP, 0, 1, 1, 0);
1954 	info->saturation = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1955 			V4L2_CID_SATURATION, 0, 256, 1, 128);
1956 	info->hue = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1957 			V4L2_CID_HUE, -180, 180, 5, 0);
1958 	info->gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1959 			V4L2_CID_GAIN, 0, 255, 1, 128);
1960 	info->auto_gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1961 			V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
1962 	info->exposure = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
1963 			V4L2_CID_EXPOSURE, 0, 65535, 1, 500);
1964 	info->auto_exposure = v4l2_ctrl_new_std_menu(&info->hdl, &ov7670_ctrl_ops,
1965 			V4L2_CID_EXPOSURE_AUTO, V4L2_EXPOSURE_MANUAL, 0,
1966 			V4L2_EXPOSURE_AUTO);
1967 	v4l2_ctrl_new_std_menu_items(&info->hdl, &ov7670_ctrl_ops,
1968 			V4L2_CID_TEST_PATTERN,
1969 			ARRAY_SIZE(ov7670_test_pattern_menu) - 1, 0, 0,
1970 			ov7670_test_pattern_menu);
1971 	sd->ctrl_handler = &info->hdl;
1972 	if (info->hdl.error) {
1973 		ret = info->hdl.error;
1974 
1975 		goto hdl_free;
1976 	}
1977 	/*
1978 	 * We have checked empirically that hw allows to read back the gain
1979 	 * value chosen by auto gain but that's not the case for auto exposure.
1980 	 */
1981 	v4l2_ctrl_auto_cluster(2, &info->auto_gain, 0, true);
1982 	v4l2_ctrl_auto_cluster(2, &info->auto_exposure,
1983 			       V4L2_EXPOSURE_MANUAL, false);
1984 	v4l2_ctrl_cluster(2, &info->saturation);
1985 
1986 #if defined(CONFIG_MEDIA_CONTROLLER)
1987 	info->pad.flags = MEDIA_PAD_FL_SOURCE;
1988 	info->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
1989 	ret = media_entity_pads_init(&info->sd.entity, 1, &info->pad);
1990 	if (ret < 0)
1991 		goto hdl_free;
1992 #endif
1993 
1994 	v4l2_ctrl_handler_setup(&info->hdl);
1995 
1996 	ret = v4l2_async_register_subdev(&info->sd);
1997 	if (ret < 0)
1998 		goto entity_cleanup;
1999 
2000 	ov7670_power_off(sd);
2001 	return 0;
2002 
2003 entity_cleanup:
2004 	media_entity_cleanup(&info->sd.entity);
2005 hdl_free:
2006 	v4l2_ctrl_handler_free(&info->hdl);
2007 power_off:
2008 	ov7670_power_off(sd);
2009 	return ret;
2010 }
2011 
2012 static int ov7670_remove(struct i2c_client *client)
2013 {
2014 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
2015 	struct ov7670_info *info = to_state(sd);
2016 
2017 	v4l2_async_unregister_subdev(sd);
2018 	v4l2_ctrl_handler_free(&info->hdl);
2019 	media_entity_cleanup(&info->sd.entity);
2020 	ov7670_power_off(sd);
2021 	return 0;
2022 }
2023 
2024 static const struct i2c_device_id ov7670_id[] = {
2025 	{ "ov7670", MODEL_OV7670 },
2026 	{ "ov7675", MODEL_OV7675 },
2027 	{ }
2028 };
2029 MODULE_DEVICE_TABLE(i2c, ov7670_id);
2030 
2031 #if IS_ENABLED(CONFIG_OF)
2032 static const struct of_device_id ov7670_of_match[] = {
2033 	{ .compatible = "ovti,ov7670", },
2034 	{ /* sentinel */ },
2035 };
2036 MODULE_DEVICE_TABLE(of, ov7670_of_match);
2037 #endif
2038 
2039 static struct i2c_driver ov7670_driver = {
2040 	.driver = {
2041 		.name	= "ov7670",
2042 		.of_match_table = of_match_ptr(ov7670_of_match),
2043 	},
2044 	.probe		= ov7670_probe,
2045 	.remove		= ov7670_remove,
2046 	.id_table	= ov7670_id,
2047 };
2048 
2049 module_i2c_driver(ov7670_driver);
2050