1 /*
2  * A V4L2 driver for OmniVision OV7670 cameras.
3  *
4  * Copyright 2006 One Laptop Per Child Association, Inc.  Written
5  * by Jonathan Corbet with substantial inspiration from Mark
6  * McClelland's ovcamchip code.
7  *
8  * Copyright 2006-7 Jonathan Corbet <corbet@lwn.net>
9  *
10  * This file may be distributed under the terms of the GNU General
11  * Public License, version 2.
12  */
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/i2c.h>
17 #include <linux/delay.h>
18 #include <linux/videodev2.h>
19 #include <media/v4l2-device.h>
20 #include <media/v4l2-chip-ident.h>
21 #include <media/v4l2-mediabus.h>
22 #include <media/ov7670.h>
23 
24 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
25 MODULE_DESCRIPTION("A low-level driver for OmniVision ov7670 sensors");
26 MODULE_LICENSE("GPL");
27 
28 static bool debug;
29 module_param(debug, bool, 0644);
30 MODULE_PARM_DESC(debug, "Debug level (0-1)");
31 
32 /*
33  * Basic window sizes.  These probably belong somewhere more globally
34  * useful.
35  */
36 #define VGA_WIDTH	640
37 #define VGA_HEIGHT	480
38 #define QVGA_WIDTH	320
39 #define QVGA_HEIGHT	240
40 #define CIF_WIDTH	352
41 #define CIF_HEIGHT	288
42 #define QCIF_WIDTH	176
43 #define	QCIF_HEIGHT	144
44 
45 /*
46  * The 7670 sits on i2c with ID 0x42
47  */
48 #define OV7670_I2C_ADDR 0x42
49 
50 /* Registers */
51 #define REG_GAIN	0x00	/* Gain lower 8 bits (rest in vref) */
52 #define REG_BLUE	0x01	/* blue gain */
53 #define REG_RED		0x02	/* red gain */
54 #define REG_VREF	0x03	/* Pieces of GAIN, VSTART, VSTOP */
55 #define REG_COM1	0x04	/* Control 1 */
56 #define  COM1_CCIR656	  0x40  /* CCIR656 enable */
57 #define REG_BAVE	0x05	/* U/B Average level */
58 #define REG_GbAVE	0x06	/* Y/Gb Average level */
59 #define REG_AECHH	0x07	/* AEC MS 5 bits */
60 #define REG_RAVE	0x08	/* V/R Average level */
61 #define REG_COM2	0x09	/* Control 2 */
62 #define  COM2_SSLEEP	  0x10	/* Soft sleep mode */
63 #define REG_PID		0x0a	/* Product ID MSB */
64 #define REG_VER		0x0b	/* Product ID LSB */
65 #define REG_COM3	0x0c	/* Control 3 */
66 #define  COM3_SWAP	  0x40	  /* Byte swap */
67 #define  COM3_SCALEEN	  0x08	  /* Enable scaling */
68 #define  COM3_DCWEN	  0x04	  /* Enable downsamp/crop/window */
69 #define REG_COM4	0x0d	/* Control 4 */
70 #define REG_COM5	0x0e	/* All "reserved" */
71 #define REG_COM6	0x0f	/* Control 6 */
72 #define REG_AECH	0x10	/* More bits of AEC value */
73 #define REG_CLKRC	0x11	/* Clocl control */
74 #define   CLK_EXT	  0x40	  /* Use external clock directly */
75 #define   CLK_SCALE	  0x3f	  /* Mask for internal clock scale */
76 #define REG_COM7	0x12	/* Control 7 */
77 #define   COM7_RESET	  0x80	  /* Register reset */
78 #define   COM7_FMT_MASK	  0x38
79 #define   COM7_FMT_VGA	  0x00
80 #define	  COM7_FMT_CIF	  0x20	  /* CIF format */
81 #define   COM7_FMT_QVGA	  0x10	  /* QVGA format */
82 #define   COM7_FMT_QCIF	  0x08	  /* QCIF format */
83 #define	  COM7_RGB	  0x04	  /* bits 0 and 2 - RGB format */
84 #define	  COM7_YUV	  0x00	  /* YUV */
85 #define	  COM7_BAYER	  0x01	  /* Bayer format */
86 #define	  COM7_PBAYER	  0x05	  /* "Processed bayer" */
87 #define REG_COM8	0x13	/* Control 8 */
88 #define   COM8_FASTAEC	  0x80	  /* Enable fast AGC/AEC */
89 #define   COM8_AECSTEP	  0x40	  /* Unlimited AEC step size */
90 #define   COM8_BFILT	  0x20	  /* Band filter enable */
91 #define   COM8_AGC	  0x04	  /* Auto gain enable */
92 #define   COM8_AWB	  0x02	  /* White balance enable */
93 #define   COM8_AEC	  0x01	  /* Auto exposure enable */
94 #define REG_COM9	0x14	/* Control 9  - gain ceiling */
95 #define REG_COM10	0x15	/* Control 10 */
96 #define   COM10_HSYNC	  0x40	  /* HSYNC instead of HREF */
97 #define   COM10_PCLK_HB	  0x20	  /* Suppress PCLK on horiz blank */
98 #define   COM10_HREF_REV  0x08	  /* Reverse HREF */
99 #define   COM10_VS_LEAD	  0x04	  /* VSYNC on clock leading edge */
100 #define   COM10_VS_NEG	  0x02	  /* VSYNC negative */
101 #define   COM10_HS_NEG	  0x01	  /* HSYNC negative */
102 #define REG_HSTART	0x17	/* Horiz start high bits */
103 #define REG_HSTOP	0x18	/* Horiz stop high bits */
104 #define REG_VSTART	0x19	/* Vert start high bits */
105 #define REG_VSTOP	0x1a	/* Vert stop high bits */
106 #define REG_PSHFT	0x1b	/* Pixel delay after HREF */
107 #define REG_MIDH	0x1c	/* Manuf. ID high */
108 #define REG_MIDL	0x1d	/* Manuf. ID low */
109 #define REG_MVFP	0x1e	/* Mirror / vflip */
110 #define   MVFP_MIRROR	  0x20	  /* Mirror image */
111 #define   MVFP_FLIP	  0x10	  /* Vertical flip */
112 
113 #define REG_AEW		0x24	/* AGC upper limit */
114 #define REG_AEB		0x25	/* AGC lower limit */
115 #define REG_VPT		0x26	/* AGC/AEC fast mode op region */
116 #define REG_HSYST	0x30	/* HSYNC rising edge delay */
117 #define REG_HSYEN	0x31	/* HSYNC falling edge delay */
118 #define REG_HREF	0x32	/* HREF pieces */
119 #define REG_TSLB	0x3a	/* lots of stuff */
120 #define   TSLB_YLAST	  0x04	  /* UYVY or VYUY - see com13 */
121 #define REG_COM11	0x3b	/* Control 11 */
122 #define   COM11_NIGHT	  0x80	  /* NIght mode enable */
123 #define   COM11_NMFR	  0x60	  /* Two bit NM frame rate */
124 #define   COM11_HZAUTO	  0x10	  /* Auto detect 50/60 Hz */
125 #define	  COM11_50HZ	  0x08	  /* Manual 50Hz select */
126 #define   COM11_EXP	  0x02
127 #define REG_COM12	0x3c	/* Control 12 */
128 #define   COM12_HREF	  0x80	  /* HREF always */
129 #define REG_COM13	0x3d	/* Control 13 */
130 #define   COM13_GAMMA	  0x80	  /* Gamma enable */
131 #define	  COM13_UVSAT	  0x40	  /* UV saturation auto adjustment */
132 #define   COM13_UVSWAP	  0x01	  /* V before U - w/TSLB */
133 #define REG_COM14	0x3e	/* Control 14 */
134 #define   COM14_DCWEN	  0x10	  /* DCW/PCLK-scale enable */
135 #define REG_EDGE	0x3f	/* Edge enhancement factor */
136 #define REG_COM15	0x40	/* Control 15 */
137 #define   COM15_R10F0	  0x00	  /* Data range 10 to F0 */
138 #define	  COM15_R01FE	  0x80	  /*            01 to FE */
139 #define   COM15_R00FF	  0xc0	  /*            00 to FF */
140 #define   COM15_RGB565	  0x10	  /* RGB565 output */
141 #define   COM15_RGB555	  0x30	  /* RGB555 output */
142 #define REG_COM16	0x41	/* Control 16 */
143 #define   COM16_AWBGAIN   0x08	  /* AWB gain enable */
144 #define REG_COM17	0x42	/* Control 17 */
145 #define   COM17_AECWIN	  0xc0	  /* AEC window - must match COM4 */
146 #define   COM17_CBAR	  0x08	  /* DSP Color bar */
147 
148 /*
149  * This matrix defines how the colors are generated, must be
150  * tweaked to adjust hue and saturation.
151  *
152  * Order: v-red, v-green, v-blue, u-red, u-green, u-blue
153  *
154  * They are nine-bit signed quantities, with the sign bit
155  * stored in 0x58.  Sign for v-red is bit 0, and up from there.
156  */
157 #define	REG_CMATRIX_BASE 0x4f
158 #define   CMATRIX_LEN 6
159 #define REG_CMATRIX_SIGN 0x58
160 
161 
162 #define REG_BRIGHT	0x55	/* Brightness */
163 #define REG_CONTRAS	0x56	/* Contrast control */
164 
165 #define REG_GFIX	0x69	/* Fix gain control */
166 
167 #define REG_REG76	0x76	/* OV's name */
168 #define   R76_BLKPCOR	  0x80	  /* Black pixel correction enable */
169 #define   R76_WHTPCOR	  0x40	  /* White pixel correction enable */
170 
171 #define REG_RGB444	0x8c	/* RGB 444 control */
172 #define   R444_ENABLE	  0x02	  /* Turn on RGB444, overrides 5x5 */
173 #define   R444_RGBX	  0x01	  /* Empty nibble at end */
174 
175 #define REG_HAECC1	0x9f	/* Hist AEC/AGC control 1 */
176 #define REG_HAECC2	0xa0	/* Hist AEC/AGC control 2 */
177 
178 #define REG_BD50MAX	0xa5	/* 50hz banding step limit */
179 #define REG_HAECC3	0xa6	/* Hist AEC/AGC control 3 */
180 #define REG_HAECC4	0xa7	/* Hist AEC/AGC control 4 */
181 #define REG_HAECC5	0xa8	/* Hist AEC/AGC control 5 */
182 #define REG_HAECC6	0xa9	/* Hist AEC/AGC control 6 */
183 #define REG_HAECC7	0xaa	/* Hist AEC/AGC control 7 */
184 #define REG_BD60MAX	0xab	/* 60hz banding step limit */
185 
186 
187 /*
188  * Information we maintain about a known sensor.
189  */
190 struct ov7670_format_struct;  /* coming later */
191 struct ov7670_info {
192 	struct v4l2_subdev sd;
193 	struct ov7670_format_struct *fmt;  /* Current format */
194 	unsigned char sat;		/* Saturation value */
195 	int hue;			/* Hue value */
196 	int min_width;			/* Filter out smaller sizes */
197 	int min_height;			/* Filter out smaller sizes */
198 	int clock_speed;		/* External clock speed (MHz) */
199 	u8 clkrc;			/* Clock divider value */
200 	bool use_smbus;			/* Use smbus I/O instead of I2C */
201 };
202 
to_state(struct v4l2_subdev * sd)203 static inline struct ov7670_info *to_state(struct v4l2_subdev *sd)
204 {
205 	return container_of(sd, struct ov7670_info, sd);
206 }
207 
208 
209 
210 /*
211  * The default register settings, as obtained from OmniVision.  There
212  * is really no making sense of most of these - lots of "reserved" values
213  * and such.
214  *
215  * These settings give VGA YUYV.
216  */
217 
218 struct regval_list {
219 	unsigned char reg_num;
220 	unsigned char value;
221 };
222 
223 static struct regval_list ov7670_default_regs[] = {
224 	{ REG_COM7, COM7_RESET },
225 /*
226  * Clock scale: 3 = 15fps
227  *              2 = 20fps
228  *              1 = 30fps
229  */
230 	{ REG_CLKRC, 0x1 },	/* OV: clock scale (30 fps) */
231 	{ REG_TSLB,  0x04 },	/* OV */
232 	{ REG_COM7, 0 },	/* VGA */
233 	/*
234 	 * Set the hardware window.  These values from OV don't entirely
235 	 * make sense - hstop is less than hstart.  But they work...
236 	 */
237 	{ REG_HSTART, 0x13 },	{ REG_HSTOP, 0x01 },
238 	{ REG_HREF, 0xb6 },	{ REG_VSTART, 0x02 },
239 	{ REG_VSTOP, 0x7a },	{ REG_VREF, 0x0a },
240 
241 	{ REG_COM3, 0 },	{ REG_COM14, 0 },
242 	/* Mystery scaling numbers */
243 	{ 0x70, 0x3a },		{ 0x71, 0x35 },
244 	{ 0x72, 0x11 },		{ 0x73, 0xf0 },
245 	{ 0xa2, 0x02 },		{ REG_COM10, 0x0 },
246 
247 	/* Gamma curve values */
248 	{ 0x7a, 0x20 },		{ 0x7b, 0x10 },
249 	{ 0x7c, 0x1e },		{ 0x7d, 0x35 },
250 	{ 0x7e, 0x5a },		{ 0x7f, 0x69 },
251 	{ 0x80, 0x76 },		{ 0x81, 0x80 },
252 	{ 0x82, 0x88 },		{ 0x83, 0x8f },
253 	{ 0x84, 0x96 },		{ 0x85, 0xa3 },
254 	{ 0x86, 0xaf },		{ 0x87, 0xc4 },
255 	{ 0x88, 0xd7 },		{ 0x89, 0xe8 },
256 
257 	/* AGC and AEC parameters.  Note we start by disabling those features,
258 	   then turn them only after tweaking the values. */
259 	{ REG_COM8, COM8_FASTAEC | COM8_AECSTEP | COM8_BFILT },
260 	{ REG_GAIN, 0 },	{ REG_AECH, 0 },
261 	{ REG_COM4, 0x40 }, /* magic reserved bit */
262 	{ REG_COM9, 0x18 }, /* 4x gain + magic rsvd bit */
263 	{ REG_BD50MAX, 0x05 },	{ REG_BD60MAX, 0x07 },
264 	{ REG_AEW, 0x95 },	{ REG_AEB, 0x33 },
265 	{ REG_VPT, 0xe3 },	{ REG_HAECC1, 0x78 },
266 	{ REG_HAECC2, 0x68 },	{ 0xa1, 0x03 }, /* magic */
267 	{ REG_HAECC3, 0xd8 },	{ REG_HAECC4, 0xd8 },
268 	{ REG_HAECC5, 0xf0 },	{ REG_HAECC6, 0x90 },
269 	{ REG_HAECC7, 0x94 },
270 	{ REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC },
271 
272 	/* Almost all of these are magic "reserved" values.  */
273 	{ REG_COM5, 0x61 },	{ REG_COM6, 0x4b },
274 	{ 0x16, 0x02 },		{ REG_MVFP, 0x07 },
275 	{ 0x21, 0x02 },		{ 0x22, 0x91 },
276 	{ 0x29, 0x07 },		{ 0x33, 0x0b },
277 	{ 0x35, 0x0b },		{ 0x37, 0x1d },
278 	{ 0x38, 0x71 },		{ 0x39, 0x2a },
279 	{ REG_COM12, 0x78 },	{ 0x4d, 0x40 },
280 	{ 0x4e, 0x20 },		{ REG_GFIX, 0 },
281 	{ 0x6b, 0x4a },		{ 0x74, 0x10 },
282 	{ 0x8d, 0x4f },		{ 0x8e, 0 },
283 	{ 0x8f, 0 },		{ 0x90, 0 },
284 	{ 0x91, 0 },		{ 0x96, 0 },
285 	{ 0x9a, 0 },		{ 0xb0, 0x84 },
286 	{ 0xb1, 0x0c },		{ 0xb2, 0x0e },
287 	{ 0xb3, 0x82 },		{ 0xb8, 0x0a },
288 
289 	/* More reserved magic, some of which tweaks white balance */
290 	{ 0x43, 0x0a },		{ 0x44, 0xf0 },
291 	{ 0x45, 0x34 },		{ 0x46, 0x58 },
292 	{ 0x47, 0x28 },		{ 0x48, 0x3a },
293 	{ 0x59, 0x88 },		{ 0x5a, 0x88 },
294 	{ 0x5b, 0x44 },		{ 0x5c, 0x67 },
295 	{ 0x5d, 0x49 },		{ 0x5e, 0x0e },
296 	{ 0x6c, 0x0a },		{ 0x6d, 0x55 },
297 	{ 0x6e, 0x11 },		{ 0x6f, 0x9f }, /* "9e for advance AWB" */
298 	{ 0x6a, 0x40 },		{ REG_BLUE, 0x40 },
299 	{ REG_RED, 0x60 },
300 	{ REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC|COM8_AWB },
301 
302 	/* Matrix coefficients */
303 	{ 0x4f, 0x80 },		{ 0x50, 0x80 },
304 	{ 0x51, 0 },		{ 0x52, 0x22 },
305 	{ 0x53, 0x5e },		{ 0x54, 0x80 },
306 	{ 0x58, 0x9e },
307 
308 	{ REG_COM16, COM16_AWBGAIN },	{ REG_EDGE, 0 },
309 	{ 0x75, 0x05 },		{ 0x76, 0xe1 },
310 	{ 0x4c, 0 },		{ 0x77, 0x01 },
311 	{ REG_COM13, 0xc3 },	{ 0x4b, 0x09 },
312 	{ 0xc9, 0x60 },		{ REG_COM16, 0x38 },
313 	{ 0x56, 0x40 },
314 
315 	{ 0x34, 0x11 },		{ REG_COM11, COM11_EXP|COM11_HZAUTO },
316 	{ 0xa4, 0x88 },		{ 0x96, 0 },
317 	{ 0x97, 0x30 },		{ 0x98, 0x20 },
318 	{ 0x99, 0x30 },		{ 0x9a, 0x84 },
319 	{ 0x9b, 0x29 },		{ 0x9c, 0x03 },
320 	{ 0x9d, 0x4c },		{ 0x9e, 0x3f },
321 	{ 0x78, 0x04 },
322 
323 	/* Extra-weird stuff.  Some sort of multiplexor register */
324 	{ 0x79, 0x01 },		{ 0xc8, 0xf0 },
325 	{ 0x79, 0x0f },		{ 0xc8, 0x00 },
326 	{ 0x79, 0x10 },		{ 0xc8, 0x7e },
327 	{ 0x79, 0x0a },		{ 0xc8, 0x80 },
328 	{ 0x79, 0x0b },		{ 0xc8, 0x01 },
329 	{ 0x79, 0x0c },		{ 0xc8, 0x0f },
330 	{ 0x79, 0x0d },		{ 0xc8, 0x20 },
331 	{ 0x79, 0x09 },		{ 0xc8, 0x80 },
332 	{ 0x79, 0x02 },		{ 0xc8, 0xc0 },
333 	{ 0x79, 0x03 },		{ 0xc8, 0x40 },
334 	{ 0x79, 0x05 },		{ 0xc8, 0x30 },
335 	{ 0x79, 0x26 },
336 
337 	{ 0xff, 0xff },	/* END MARKER */
338 };
339 
340 
341 /*
342  * Here we'll try to encapsulate the changes for just the output
343  * video format.
344  *
345  * RGB656 and YUV422 come from OV; RGB444 is homebrewed.
346  *
347  * IMPORTANT RULE: the first entry must be for COM7, see ov7670_s_fmt for why.
348  */
349 
350 
351 static struct regval_list ov7670_fmt_yuv422[] = {
352 	{ REG_COM7, 0x0 },  /* Selects YUV mode */
353 	{ REG_RGB444, 0 },	/* No RGB444 please */
354 	{ REG_COM1, 0 },	/* CCIR601 */
355 	{ REG_COM15, COM15_R00FF },
356 	{ REG_COM9, 0x18 }, /* 4x gain ceiling; 0x8 is reserved bit */
357 	{ 0x4f, 0x80 }, 	/* "matrix coefficient 1" */
358 	{ 0x50, 0x80 }, 	/* "matrix coefficient 2" */
359 	{ 0x51, 0    },		/* vb */
360 	{ 0x52, 0x22 }, 	/* "matrix coefficient 4" */
361 	{ 0x53, 0x5e }, 	/* "matrix coefficient 5" */
362 	{ 0x54, 0x80 }, 	/* "matrix coefficient 6" */
363 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT },
364 	{ 0xff, 0xff },
365 };
366 
367 static struct regval_list ov7670_fmt_rgb565[] = {
368 	{ REG_COM7, COM7_RGB },	/* Selects RGB mode */
369 	{ REG_RGB444, 0 },	/* No RGB444 please */
370 	{ REG_COM1, 0x0 },	/* CCIR601 */
371 	{ REG_COM15, COM15_RGB565 },
372 	{ REG_COM9, 0x38 }, 	/* 16x gain ceiling; 0x8 is reserved bit */
373 	{ 0x4f, 0xb3 }, 	/* "matrix coefficient 1" */
374 	{ 0x50, 0xb3 }, 	/* "matrix coefficient 2" */
375 	{ 0x51, 0    },		/* vb */
376 	{ 0x52, 0x3d }, 	/* "matrix coefficient 4" */
377 	{ 0x53, 0xa7 }, 	/* "matrix coefficient 5" */
378 	{ 0x54, 0xe4 }, 	/* "matrix coefficient 6" */
379 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT },
380 	{ 0xff, 0xff },
381 };
382 
383 static struct regval_list ov7670_fmt_rgb444[] = {
384 	{ REG_COM7, COM7_RGB },	/* Selects RGB mode */
385 	{ REG_RGB444, R444_ENABLE },	/* Enable xxxxrrrr ggggbbbb */
386 	{ REG_COM1, 0x0 },	/* CCIR601 */
387 	{ REG_COM15, COM15_R01FE|COM15_RGB565 }, /* Data range needed? */
388 	{ REG_COM9, 0x38 }, 	/* 16x gain ceiling; 0x8 is reserved bit */
389 	{ 0x4f, 0xb3 }, 	/* "matrix coefficient 1" */
390 	{ 0x50, 0xb3 }, 	/* "matrix coefficient 2" */
391 	{ 0x51, 0    },		/* vb */
392 	{ 0x52, 0x3d }, 	/* "matrix coefficient 4" */
393 	{ 0x53, 0xa7 }, 	/* "matrix coefficient 5" */
394 	{ 0x54, 0xe4 }, 	/* "matrix coefficient 6" */
395 	{ REG_COM13, COM13_GAMMA|COM13_UVSAT|0x2 },  /* Magic rsvd bit */
396 	{ 0xff, 0xff },
397 };
398 
399 static struct regval_list ov7670_fmt_raw[] = {
400 	{ REG_COM7, COM7_BAYER },
401 	{ REG_COM13, 0x08 }, /* No gamma, magic rsvd bit */
402 	{ REG_COM16, 0x3d }, /* Edge enhancement, denoise */
403 	{ REG_REG76, 0xe1 }, /* Pix correction, magic rsvd */
404 	{ 0xff, 0xff },
405 };
406 
407 
408 
409 /*
410  * Low-level register I/O.
411  *
412  * Note that there are two versions of these.  On the XO 1, the
413  * i2c controller only does SMBUS, so that's what we use.  The
414  * ov7670 is not really an SMBUS device, though, so the communication
415  * is not always entirely reliable.
416  */
ov7670_read_smbus(struct v4l2_subdev * sd,unsigned char reg,unsigned char * value)417 static int ov7670_read_smbus(struct v4l2_subdev *sd, unsigned char reg,
418 		unsigned char *value)
419 {
420 	struct i2c_client *client = v4l2_get_subdevdata(sd);
421 	int ret;
422 
423 	ret = i2c_smbus_read_byte_data(client, reg);
424 	if (ret >= 0) {
425 		*value = (unsigned char)ret;
426 		ret = 0;
427 	}
428 	return ret;
429 }
430 
431 
ov7670_write_smbus(struct v4l2_subdev * sd,unsigned char reg,unsigned char value)432 static int ov7670_write_smbus(struct v4l2_subdev *sd, unsigned char reg,
433 		unsigned char value)
434 {
435 	struct i2c_client *client = v4l2_get_subdevdata(sd);
436 	int ret = i2c_smbus_write_byte_data(client, reg, value);
437 
438 	if (reg == REG_COM7 && (value & COM7_RESET))
439 		msleep(5);  /* Wait for reset to run */
440 	return ret;
441 }
442 
443 /*
444  * On most platforms, we'd rather do straight i2c I/O.
445  */
ov7670_read_i2c(struct v4l2_subdev * sd,unsigned char reg,unsigned char * value)446 static int ov7670_read_i2c(struct v4l2_subdev *sd, unsigned char reg,
447 		unsigned char *value)
448 {
449 	struct i2c_client *client = v4l2_get_subdevdata(sd);
450 	u8 data = reg;
451 	struct i2c_msg msg;
452 	int ret;
453 
454 	/*
455 	 * Send out the register address...
456 	 */
457 	msg.addr = client->addr;
458 	msg.flags = 0;
459 	msg.len = 1;
460 	msg.buf = &data;
461 	ret = i2c_transfer(client->adapter, &msg, 1);
462 	if (ret < 0) {
463 		printk(KERN_ERR "Error %d on register write\n", ret);
464 		return ret;
465 	}
466 	/*
467 	 * ...then read back the result.
468 	 */
469 	msg.flags = I2C_M_RD;
470 	ret = i2c_transfer(client->adapter, &msg, 1);
471 	if (ret >= 0) {
472 		*value = data;
473 		ret = 0;
474 	}
475 	return ret;
476 }
477 
478 
ov7670_write_i2c(struct v4l2_subdev * sd,unsigned char reg,unsigned char value)479 static int ov7670_write_i2c(struct v4l2_subdev *sd, unsigned char reg,
480 		unsigned char value)
481 {
482 	struct i2c_client *client = v4l2_get_subdevdata(sd);
483 	struct i2c_msg msg;
484 	unsigned char data[2] = { reg, value };
485 	int ret;
486 
487 	msg.addr = client->addr;
488 	msg.flags = 0;
489 	msg.len = 2;
490 	msg.buf = data;
491 	ret = i2c_transfer(client->adapter, &msg, 1);
492 	if (ret > 0)
493 		ret = 0;
494 	if (reg == REG_COM7 && (value & COM7_RESET))
495 		msleep(5);  /* Wait for reset to run */
496 	return ret;
497 }
498 
ov7670_read(struct v4l2_subdev * sd,unsigned char reg,unsigned char * value)499 static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
500 		unsigned char *value)
501 {
502 	struct ov7670_info *info = to_state(sd);
503 	if (info->use_smbus)
504 		return ov7670_read_smbus(sd, reg, value);
505 	else
506 		return ov7670_read_i2c(sd, reg, value);
507 }
508 
ov7670_write(struct v4l2_subdev * sd,unsigned char reg,unsigned char value)509 static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
510 		unsigned char value)
511 {
512 	struct ov7670_info *info = to_state(sd);
513 	if (info->use_smbus)
514 		return ov7670_write_smbus(sd, reg, value);
515 	else
516 		return ov7670_write_i2c(sd, reg, value);
517 }
518 
519 /*
520  * Write a list of register settings; ff/ff stops the process.
521  */
ov7670_write_array(struct v4l2_subdev * sd,struct regval_list * vals)522 static int ov7670_write_array(struct v4l2_subdev *sd, struct regval_list *vals)
523 {
524 	while (vals->reg_num != 0xff || vals->value != 0xff) {
525 		int ret = ov7670_write(sd, vals->reg_num, vals->value);
526 		if (ret < 0)
527 			return ret;
528 		vals++;
529 	}
530 	return 0;
531 }
532 
533 
534 /*
535  * Stuff that knows about the sensor.
536  */
ov7670_reset(struct v4l2_subdev * sd,u32 val)537 static int ov7670_reset(struct v4l2_subdev *sd, u32 val)
538 {
539 	ov7670_write(sd, REG_COM7, COM7_RESET);
540 	msleep(1);
541 	return 0;
542 }
543 
544 
ov7670_init(struct v4l2_subdev * sd,u32 val)545 static int ov7670_init(struct v4l2_subdev *sd, u32 val)
546 {
547 	return ov7670_write_array(sd, ov7670_default_regs);
548 }
549 
550 
551 
ov7670_detect(struct v4l2_subdev * sd)552 static int ov7670_detect(struct v4l2_subdev *sd)
553 {
554 	unsigned char v;
555 	int ret;
556 
557 	ret = ov7670_init(sd, 0);
558 	if (ret < 0)
559 		return ret;
560 	ret = ov7670_read(sd, REG_MIDH, &v);
561 	if (ret < 0)
562 		return ret;
563 	if (v != 0x7f) /* OV manuf. id. */
564 		return -ENODEV;
565 	ret = ov7670_read(sd, REG_MIDL, &v);
566 	if (ret < 0)
567 		return ret;
568 	if (v != 0xa2)
569 		return -ENODEV;
570 	/*
571 	 * OK, we know we have an OmniVision chip...but which one?
572 	 */
573 	ret = ov7670_read(sd, REG_PID, &v);
574 	if (ret < 0)
575 		return ret;
576 	if (v != 0x76)  /* PID + VER = 0x76 / 0x73 */
577 		return -ENODEV;
578 	ret = ov7670_read(sd, REG_VER, &v);
579 	if (ret < 0)
580 		return ret;
581 	if (v != 0x73)  /* PID + VER = 0x76 / 0x73 */
582 		return -ENODEV;
583 	return 0;
584 }
585 
586 
587 /*
588  * Store information about the video data format.  The color matrix
589  * is deeply tied into the format, so keep the relevant values here.
590  * The magic matrix numbers come from OmniVision.
591  */
592 static struct ov7670_format_struct {
593 	enum v4l2_mbus_pixelcode mbus_code;
594 	enum v4l2_colorspace colorspace;
595 	struct regval_list *regs;
596 	int cmatrix[CMATRIX_LEN];
597 } ov7670_formats[] = {
598 	{
599 		.mbus_code	= V4L2_MBUS_FMT_YUYV8_2X8,
600 		.colorspace	= V4L2_COLORSPACE_JPEG,
601 		.regs 		= ov7670_fmt_yuv422,
602 		.cmatrix	= { 128, -128, 0, -34, -94, 128 },
603 	},
604 	{
605 		.mbus_code	= V4L2_MBUS_FMT_RGB444_2X8_PADHI_LE,
606 		.colorspace	= V4L2_COLORSPACE_SRGB,
607 		.regs		= ov7670_fmt_rgb444,
608 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
609 	},
610 	{
611 		.mbus_code	= V4L2_MBUS_FMT_RGB565_2X8_LE,
612 		.colorspace	= V4L2_COLORSPACE_SRGB,
613 		.regs		= ov7670_fmt_rgb565,
614 		.cmatrix	= { 179, -179, 0, -61, -176, 228 },
615 	},
616 	{
617 		.mbus_code	= V4L2_MBUS_FMT_SBGGR8_1X8,
618 		.colorspace	= V4L2_COLORSPACE_SRGB,
619 		.regs 		= ov7670_fmt_raw,
620 		.cmatrix	= { 0, 0, 0, 0, 0, 0 },
621 	},
622 };
623 #define N_OV7670_FMTS ARRAY_SIZE(ov7670_formats)
624 
625 
626 /*
627  * Then there is the issue of window sizes.  Try to capture the info here.
628  */
629 
630 /*
631  * QCIF mode is done (by OV) in a very strange way - it actually looks like
632  * VGA with weird scaling options - they do *not* use the canned QCIF mode
633  * which is allegedly provided by the sensor.  So here's the weird register
634  * settings.
635  */
636 static struct regval_list ov7670_qcif_regs[] = {
637 	{ REG_COM3, COM3_SCALEEN|COM3_DCWEN },
638 	{ REG_COM3, COM3_DCWEN },
639 	{ REG_COM14, COM14_DCWEN | 0x01},
640 	{ 0x73, 0xf1 },
641 	{ 0xa2, 0x52 },
642 	{ 0x7b, 0x1c },
643 	{ 0x7c, 0x28 },
644 	{ 0x7d, 0x3c },
645 	{ 0x7f, 0x69 },
646 	{ REG_COM9, 0x38 },
647 	{ 0xa1, 0x0b },
648 	{ 0x74, 0x19 },
649 	{ 0x9a, 0x80 },
650 	{ 0x43, 0x14 },
651 	{ REG_COM13, 0xc0 },
652 	{ 0xff, 0xff },
653 };
654 
655 static struct ov7670_win_size {
656 	int	width;
657 	int	height;
658 	unsigned char com7_bit;
659 	int	hstart;		/* Start/stop values for the camera.  Note */
660 	int	hstop;		/* that they do not always make complete */
661 	int	vstart;		/* sense to humans, but evidently the sensor */
662 	int	vstop;		/* will do the right thing... */
663 	struct regval_list *regs; /* Regs to tweak */
664 /* h/vref stuff */
665 } ov7670_win_sizes[] = {
666 	/* VGA */
667 	{
668 		.width		= VGA_WIDTH,
669 		.height		= VGA_HEIGHT,
670 		.com7_bit	= COM7_FMT_VGA,
671 		.hstart		= 158,		/* These values from */
672 		.hstop		=  14,		/* Omnivision */
673 		.vstart		=  10,
674 		.vstop		= 490,
675 		.regs 		= NULL,
676 	},
677 	/* CIF */
678 	{
679 		.width		= CIF_WIDTH,
680 		.height		= CIF_HEIGHT,
681 		.com7_bit	= COM7_FMT_CIF,
682 		.hstart		= 170,		/* Empirically determined */
683 		.hstop		=  90,
684 		.vstart		=  14,
685 		.vstop		= 494,
686 		.regs 		= NULL,
687 	},
688 	/* QVGA */
689 	{
690 		.width		= QVGA_WIDTH,
691 		.height		= QVGA_HEIGHT,
692 		.com7_bit	= COM7_FMT_QVGA,
693 		.hstart		= 168,		/* Empirically determined */
694 		.hstop		=  24,
695 		.vstart		=  12,
696 		.vstop		= 492,
697 		.regs 		= NULL,
698 	},
699 	/* QCIF */
700 	{
701 		.width		= QCIF_WIDTH,
702 		.height		= QCIF_HEIGHT,
703 		.com7_bit	= COM7_FMT_VGA, /* see comment above */
704 		.hstart		= 456,		/* Empirically determined */
705 		.hstop		=  24,
706 		.vstart		=  14,
707 		.vstop		= 494,
708 		.regs 		= ov7670_qcif_regs,
709 	},
710 };
711 
712 #define N_WIN_SIZES (ARRAY_SIZE(ov7670_win_sizes))
713 
714 
715 /*
716  * Store a set of start/stop values into the camera.
717  */
ov7670_set_hw(struct v4l2_subdev * sd,int hstart,int hstop,int vstart,int vstop)718 static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop,
719 		int vstart, int vstop)
720 {
721 	int ret;
722 	unsigned char v;
723 /*
724  * Horizontal: 11 bits, top 8 live in hstart and hstop.  Bottom 3 of
725  * hstart are in href[2:0], bottom 3 of hstop in href[5:3].  There is
726  * a mystery "edge offset" value in the top two bits of href.
727  */
728 	ret =  ov7670_write(sd, REG_HSTART, (hstart >> 3) & 0xff);
729 	ret += ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff);
730 	ret += ov7670_read(sd, REG_HREF, &v);
731 	v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7);
732 	msleep(10);
733 	ret += ov7670_write(sd, REG_HREF, v);
734 /*
735  * Vertical: similar arrangement, but only 10 bits.
736  */
737 	ret += ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff);
738 	ret += ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff);
739 	ret += ov7670_read(sd, REG_VREF, &v);
740 	v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3);
741 	msleep(10);
742 	ret += ov7670_write(sd, REG_VREF, v);
743 	return ret;
744 }
745 
746 
ov7670_enum_mbus_fmt(struct v4l2_subdev * sd,unsigned index,enum v4l2_mbus_pixelcode * code)747 static int ov7670_enum_mbus_fmt(struct v4l2_subdev *sd, unsigned index,
748 					enum v4l2_mbus_pixelcode *code)
749 {
750 	if (index >= N_OV7670_FMTS)
751 		return -EINVAL;
752 
753 	*code = ov7670_formats[index].mbus_code;
754 	return 0;
755 }
756 
ov7670_try_fmt_internal(struct v4l2_subdev * sd,struct v4l2_mbus_framefmt * fmt,struct ov7670_format_struct ** ret_fmt,struct ov7670_win_size ** ret_wsize)757 static int ov7670_try_fmt_internal(struct v4l2_subdev *sd,
758 		struct v4l2_mbus_framefmt *fmt,
759 		struct ov7670_format_struct **ret_fmt,
760 		struct ov7670_win_size **ret_wsize)
761 {
762 	int index;
763 	struct ov7670_win_size *wsize;
764 
765 	for (index = 0; index < N_OV7670_FMTS; index++)
766 		if (ov7670_formats[index].mbus_code == fmt->code)
767 			break;
768 	if (index >= N_OV7670_FMTS) {
769 		/* default to first format */
770 		index = 0;
771 		fmt->code = ov7670_formats[0].mbus_code;
772 	}
773 	if (ret_fmt != NULL)
774 		*ret_fmt = ov7670_formats + index;
775 	/*
776 	 * Fields: the OV devices claim to be progressive.
777 	 */
778 	fmt->field = V4L2_FIELD_NONE;
779 	/*
780 	 * Round requested image size down to the nearest
781 	 * we support, but not below the smallest.
782 	 */
783 	for (wsize = ov7670_win_sizes; wsize < ov7670_win_sizes + N_WIN_SIZES;
784 	     wsize++)
785 		if (fmt->width >= wsize->width && fmt->height >= wsize->height)
786 			break;
787 	if (wsize >= ov7670_win_sizes + N_WIN_SIZES)
788 		wsize--;   /* Take the smallest one */
789 	if (ret_wsize != NULL)
790 		*ret_wsize = wsize;
791 	/*
792 	 * Note the size we'll actually handle.
793 	 */
794 	fmt->width = wsize->width;
795 	fmt->height = wsize->height;
796 	fmt->colorspace = ov7670_formats[index].colorspace;
797 	return 0;
798 }
799 
ov7670_try_mbus_fmt(struct v4l2_subdev * sd,struct v4l2_mbus_framefmt * fmt)800 static int ov7670_try_mbus_fmt(struct v4l2_subdev *sd,
801 			    struct v4l2_mbus_framefmt *fmt)
802 {
803 	return ov7670_try_fmt_internal(sd, fmt, NULL, NULL);
804 }
805 
806 /*
807  * Set a format.
808  */
ov7670_s_mbus_fmt(struct v4l2_subdev * sd,struct v4l2_mbus_framefmt * fmt)809 static int ov7670_s_mbus_fmt(struct v4l2_subdev *sd,
810 			  struct v4l2_mbus_framefmt *fmt)
811 {
812 	struct ov7670_format_struct *ovfmt;
813 	struct ov7670_win_size *wsize;
814 	struct ov7670_info *info = to_state(sd);
815 	unsigned char com7;
816 	int ret;
817 
818 	ret = ov7670_try_fmt_internal(sd, fmt, &ovfmt, &wsize);
819 
820 	if (ret)
821 		return ret;
822 	/*
823 	 * COM7 is a pain in the ass, it doesn't like to be read then
824 	 * quickly written afterward.  But we have everything we need
825 	 * to set it absolutely here, as long as the format-specific
826 	 * register sets list it first.
827 	 */
828 	com7 = ovfmt->regs[0].value;
829 	com7 |= wsize->com7_bit;
830 	ov7670_write(sd, REG_COM7, com7);
831 	/*
832 	 * Now write the rest of the array.  Also store start/stops
833 	 */
834 	ov7670_write_array(sd, ovfmt->regs + 1);
835 	ov7670_set_hw(sd, wsize->hstart, wsize->hstop, wsize->vstart,
836 			wsize->vstop);
837 	ret = 0;
838 	if (wsize->regs)
839 		ret = ov7670_write_array(sd, wsize->regs);
840 	info->fmt = ovfmt;
841 
842 	/*
843 	 * If we're running RGB565, we must rewrite clkrc after setting
844 	 * the other parameters or the image looks poor.  If we're *not*
845 	 * doing RGB565, we must not rewrite clkrc or the image looks
846 	 * *really* poor.
847 	 *
848 	 * (Update) Now that we retain clkrc state, we should be able
849 	 * to write it unconditionally, and that will make the frame
850 	 * rate persistent too.
851 	 */
852 	if (ret == 0)
853 		ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
854 	return 0;
855 }
856 
857 /*
858  * Implement G/S_PARM.  There is a "high quality" mode we could try
859  * to do someday; for now, we just do the frame rate tweak.
860  */
ov7670_g_parm(struct v4l2_subdev * sd,struct v4l2_streamparm * parms)861 static int ov7670_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
862 {
863 	struct v4l2_captureparm *cp = &parms->parm.capture;
864 	struct ov7670_info *info = to_state(sd);
865 
866 	if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
867 		return -EINVAL;
868 
869 	memset(cp, 0, sizeof(struct v4l2_captureparm));
870 	cp->capability = V4L2_CAP_TIMEPERFRAME;
871 	cp->timeperframe.numerator = 1;
872 	cp->timeperframe.denominator = info->clock_speed;
873 	if ((info->clkrc & CLK_EXT) == 0 && (info->clkrc & CLK_SCALE) > 1)
874 		cp->timeperframe.denominator /= (info->clkrc & CLK_SCALE);
875 	return 0;
876 }
877 
ov7670_s_parm(struct v4l2_subdev * sd,struct v4l2_streamparm * parms)878 static int ov7670_s_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
879 {
880 	struct v4l2_captureparm *cp = &parms->parm.capture;
881 	struct v4l2_fract *tpf = &cp->timeperframe;
882 	struct ov7670_info *info = to_state(sd);
883 	int div;
884 
885 	if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
886 		return -EINVAL;
887 	if (cp->extendedmode != 0)
888 		return -EINVAL;
889 
890 	if (tpf->numerator == 0 || tpf->denominator == 0)
891 		div = 1;  /* Reset to full rate */
892 	else
893 		div = (tpf->numerator * info->clock_speed) / tpf->denominator;
894 	if (div == 0)
895 		div = 1;
896 	else if (div > CLK_SCALE)
897 		div = CLK_SCALE;
898 	info->clkrc = (info->clkrc & 0x80) | div;
899 	tpf->numerator = 1;
900 	tpf->denominator = info->clock_speed / div;
901 	return ov7670_write(sd, REG_CLKRC, info->clkrc);
902 }
903 
904 
905 /*
906  * Frame intervals.  Since frame rates are controlled with the clock
907  * divider, we can only do 30/n for integer n values.  So no continuous
908  * or stepwise options.  Here we just pick a handful of logical values.
909  */
910 
911 static int ov7670_frame_rates[] = { 30, 15, 10, 5, 1 };
912 
ov7670_enum_frameintervals(struct v4l2_subdev * sd,struct v4l2_frmivalenum * interval)913 static int ov7670_enum_frameintervals(struct v4l2_subdev *sd,
914 		struct v4l2_frmivalenum *interval)
915 {
916 	if (interval->index >= ARRAY_SIZE(ov7670_frame_rates))
917 		return -EINVAL;
918 	interval->type = V4L2_FRMIVAL_TYPE_DISCRETE;
919 	interval->discrete.numerator = 1;
920 	interval->discrete.denominator = ov7670_frame_rates[interval->index];
921 	return 0;
922 }
923 
924 /*
925  * Frame size enumeration
926  */
ov7670_enum_framesizes(struct v4l2_subdev * sd,struct v4l2_frmsizeenum * fsize)927 static int ov7670_enum_framesizes(struct v4l2_subdev *sd,
928 		struct v4l2_frmsizeenum *fsize)
929 {
930 	struct ov7670_info *info = to_state(sd);
931 	int i;
932 	int num_valid = -1;
933 	__u32 index = fsize->index;
934 
935 	/*
936 	 * If a minimum width/height was requested, filter out the capture
937 	 * windows that fall outside that.
938 	 */
939 	for (i = 0; i < N_WIN_SIZES; i++) {
940 		struct ov7670_win_size *win = &ov7670_win_sizes[index];
941 		if (info->min_width && win->width < info->min_width)
942 			continue;
943 		if (info->min_height && win->height < info->min_height)
944 			continue;
945 		if (index == ++num_valid) {
946 			fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
947 			fsize->discrete.width = win->width;
948 			fsize->discrete.height = win->height;
949 			return 0;
950 		}
951 	}
952 
953 	return -EINVAL;
954 }
955 
956 /*
957  * Code for dealing with controls.
958  */
959 
ov7670_store_cmatrix(struct v4l2_subdev * sd,int matrix[CMATRIX_LEN])960 static int ov7670_store_cmatrix(struct v4l2_subdev *sd,
961 		int matrix[CMATRIX_LEN])
962 {
963 	int i, ret;
964 	unsigned char signbits = 0;
965 
966 	/*
967 	 * Weird crap seems to exist in the upper part of
968 	 * the sign bits register, so let's preserve it.
969 	 */
970 	ret = ov7670_read(sd, REG_CMATRIX_SIGN, &signbits);
971 	signbits &= 0xc0;
972 
973 	for (i = 0; i < CMATRIX_LEN; i++) {
974 		unsigned char raw;
975 
976 		if (matrix[i] < 0) {
977 			signbits |= (1 << i);
978 			if (matrix[i] < -255)
979 				raw = 0xff;
980 			else
981 				raw = (-1 * matrix[i]) & 0xff;
982 		}
983 		else {
984 			if (matrix[i] > 255)
985 				raw = 0xff;
986 			else
987 				raw = matrix[i] & 0xff;
988 		}
989 		ret += ov7670_write(sd, REG_CMATRIX_BASE + i, raw);
990 	}
991 	ret += ov7670_write(sd, REG_CMATRIX_SIGN, signbits);
992 	return ret;
993 }
994 
995 
996 /*
997  * Hue also requires messing with the color matrix.  It also requires
998  * trig functions, which tend not to be well supported in the kernel.
999  * So here is a simple table of sine values, 0-90 degrees, in steps
1000  * of five degrees.  Values are multiplied by 1000.
1001  *
1002  * The following naive approximate trig functions require an argument
1003  * carefully limited to -180 <= theta <= 180.
1004  */
1005 #define SIN_STEP 5
1006 static const int ov7670_sin_table[] = {
1007 	   0,	 87,   173,   258,   342,   422,
1008 	 499,	573,   642,   707,   766,   819,
1009 	 866,	906,   939,   965,   984,   996,
1010 	1000
1011 };
1012 
ov7670_sine(int theta)1013 static int ov7670_sine(int theta)
1014 {
1015 	int chs = 1;
1016 	int sine;
1017 
1018 	if (theta < 0) {
1019 		theta = -theta;
1020 		chs = -1;
1021 	}
1022 	if (theta <= 90)
1023 		sine = ov7670_sin_table[theta/SIN_STEP];
1024 	else {
1025 		theta -= 90;
1026 		sine = 1000 - ov7670_sin_table[theta/SIN_STEP];
1027 	}
1028 	return sine*chs;
1029 }
1030 
ov7670_cosine(int theta)1031 static int ov7670_cosine(int theta)
1032 {
1033 	theta = 90 - theta;
1034 	if (theta > 180)
1035 		theta -= 360;
1036 	else if (theta < -180)
1037 		theta += 360;
1038 	return ov7670_sine(theta);
1039 }
1040 
1041 
1042 
1043 
ov7670_calc_cmatrix(struct ov7670_info * info,int matrix[CMATRIX_LEN])1044 static void ov7670_calc_cmatrix(struct ov7670_info *info,
1045 		int matrix[CMATRIX_LEN])
1046 {
1047 	int i;
1048 	/*
1049 	 * Apply the current saturation setting first.
1050 	 */
1051 	for (i = 0; i < CMATRIX_LEN; i++)
1052 		matrix[i] = (info->fmt->cmatrix[i]*info->sat) >> 7;
1053 	/*
1054 	 * Then, if need be, rotate the hue value.
1055 	 */
1056 	if (info->hue != 0) {
1057 		int sinth, costh, tmpmatrix[CMATRIX_LEN];
1058 
1059 		memcpy(tmpmatrix, matrix, CMATRIX_LEN*sizeof(int));
1060 		sinth = ov7670_sine(info->hue);
1061 		costh = ov7670_cosine(info->hue);
1062 
1063 		matrix[0] = (matrix[3]*sinth + matrix[0]*costh)/1000;
1064 		matrix[1] = (matrix[4]*sinth + matrix[1]*costh)/1000;
1065 		matrix[2] = (matrix[5]*sinth + matrix[2]*costh)/1000;
1066 		matrix[3] = (matrix[3]*costh - matrix[0]*sinth)/1000;
1067 		matrix[4] = (matrix[4]*costh - matrix[1]*sinth)/1000;
1068 		matrix[5] = (matrix[5]*costh - matrix[2]*sinth)/1000;
1069 	}
1070 }
1071 
1072 
1073 
ov7670_s_sat(struct v4l2_subdev * sd,int value)1074 static int ov7670_s_sat(struct v4l2_subdev *sd, int value)
1075 {
1076 	struct ov7670_info *info = to_state(sd);
1077 	int matrix[CMATRIX_LEN];
1078 	int ret;
1079 
1080 	info->sat = value;
1081 	ov7670_calc_cmatrix(info, matrix);
1082 	ret = ov7670_store_cmatrix(sd, matrix);
1083 	return ret;
1084 }
1085 
ov7670_g_sat(struct v4l2_subdev * sd,__s32 * value)1086 static int ov7670_g_sat(struct v4l2_subdev *sd, __s32 *value)
1087 {
1088 	struct ov7670_info *info = to_state(sd);
1089 
1090 	*value = info->sat;
1091 	return 0;
1092 }
1093 
ov7670_s_hue(struct v4l2_subdev * sd,int value)1094 static int ov7670_s_hue(struct v4l2_subdev *sd, int value)
1095 {
1096 	struct ov7670_info *info = to_state(sd);
1097 	int matrix[CMATRIX_LEN];
1098 	int ret;
1099 
1100 	if (value < -180 || value > 180)
1101 		return -EINVAL;
1102 	info->hue = value;
1103 	ov7670_calc_cmatrix(info, matrix);
1104 	ret = ov7670_store_cmatrix(sd, matrix);
1105 	return ret;
1106 }
1107 
1108 
ov7670_g_hue(struct v4l2_subdev * sd,__s32 * value)1109 static int ov7670_g_hue(struct v4l2_subdev *sd, __s32 *value)
1110 {
1111 	struct ov7670_info *info = to_state(sd);
1112 
1113 	*value = info->hue;
1114 	return 0;
1115 }
1116 
1117 
1118 /*
1119  * Some weird registers seem to store values in a sign/magnitude format!
1120  */
ov7670_sm_to_abs(unsigned char v)1121 static unsigned char ov7670_sm_to_abs(unsigned char v)
1122 {
1123 	if ((v & 0x80) == 0)
1124 		return v + 128;
1125 	return 128 - (v & 0x7f);
1126 }
1127 
1128 
ov7670_abs_to_sm(unsigned char v)1129 static unsigned char ov7670_abs_to_sm(unsigned char v)
1130 {
1131 	if (v > 127)
1132 		return v & 0x7f;
1133 	return (128 - v) | 0x80;
1134 }
1135 
ov7670_s_brightness(struct v4l2_subdev * sd,int value)1136 static int ov7670_s_brightness(struct v4l2_subdev *sd, int value)
1137 {
1138 	unsigned char com8 = 0, v;
1139 	int ret;
1140 
1141 	ov7670_read(sd, REG_COM8, &com8);
1142 	com8 &= ~COM8_AEC;
1143 	ov7670_write(sd, REG_COM8, com8);
1144 	v = ov7670_abs_to_sm(value);
1145 	ret = ov7670_write(sd, REG_BRIGHT, v);
1146 	return ret;
1147 }
1148 
ov7670_g_brightness(struct v4l2_subdev * sd,__s32 * value)1149 static int ov7670_g_brightness(struct v4l2_subdev *sd, __s32 *value)
1150 {
1151 	unsigned char v = 0;
1152 	int ret = ov7670_read(sd, REG_BRIGHT, &v);
1153 
1154 	*value = ov7670_sm_to_abs(v);
1155 	return ret;
1156 }
1157 
ov7670_s_contrast(struct v4l2_subdev * sd,int value)1158 static int ov7670_s_contrast(struct v4l2_subdev *sd, int value)
1159 {
1160 	return ov7670_write(sd, REG_CONTRAS, (unsigned char) value);
1161 }
1162 
ov7670_g_contrast(struct v4l2_subdev * sd,__s32 * value)1163 static int ov7670_g_contrast(struct v4l2_subdev *sd, __s32 *value)
1164 {
1165 	unsigned char v = 0;
1166 	int ret = ov7670_read(sd, REG_CONTRAS, &v);
1167 
1168 	*value = v;
1169 	return ret;
1170 }
1171 
ov7670_g_hflip(struct v4l2_subdev * sd,__s32 * value)1172 static int ov7670_g_hflip(struct v4l2_subdev *sd, __s32 *value)
1173 {
1174 	int ret;
1175 	unsigned char v = 0;
1176 
1177 	ret = ov7670_read(sd, REG_MVFP, &v);
1178 	*value = (v & MVFP_MIRROR) == MVFP_MIRROR;
1179 	return ret;
1180 }
1181 
1182 
ov7670_s_hflip(struct v4l2_subdev * sd,int value)1183 static int ov7670_s_hflip(struct v4l2_subdev *sd, int value)
1184 {
1185 	unsigned char v = 0;
1186 	int ret;
1187 
1188 	ret = ov7670_read(sd, REG_MVFP, &v);
1189 	if (value)
1190 		v |= MVFP_MIRROR;
1191 	else
1192 		v &= ~MVFP_MIRROR;
1193 	msleep(10);  /* FIXME */
1194 	ret += ov7670_write(sd, REG_MVFP, v);
1195 	return ret;
1196 }
1197 
1198 
1199 
ov7670_g_vflip(struct v4l2_subdev * sd,__s32 * value)1200 static int ov7670_g_vflip(struct v4l2_subdev *sd, __s32 *value)
1201 {
1202 	int ret;
1203 	unsigned char v = 0;
1204 
1205 	ret = ov7670_read(sd, REG_MVFP, &v);
1206 	*value = (v & MVFP_FLIP) == MVFP_FLIP;
1207 	return ret;
1208 }
1209 
1210 
ov7670_s_vflip(struct v4l2_subdev * sd,int value)1211 static int ov7670_s_vflip(struct v4l2_subdev *sd, int value)
1212 {
1213 	unsigned char v = 0;
1214 	int ret;
1215 
1216 	ret = ov7670_read(sd, REG_MVFP, &v);
1217 	if (value)
1218 		v |= MVFP_FLIP;
1219 	else
1220 		v &= ~MVFP_FLIP;
1221 	msleep(10);  /* FIXME */
1222 	ret += ov7670_write(sd, REG_MVFP, v);
1223 	return ret;
1224 }
1225 
1226 /*
1227  * GAIN is split between REG_GAIN and REG_VREF[7:6].  If one believes
1228  * the data sheet, the VREF parts should be the most significant, but
1229  * experience shows otherwise.  There seems to be little value in
1230  * messing with the VREF bits, so we leave them alone.
1231  */
ov7670_g_gain(struct v4l2_subdev * sd,__s32 * value)1232 static int ov7670_g_gain(struct v4l2_subdev *sd, __s32 *value)
1233 {
1234 	int ret;
1235 	unsigned char gain;
1236 
1237 	ret = ov7670_read(sd, REG_GAIN, &gain);
1238 	*value = gain;
1239 	return ret;
1240 }
1241 
ov7670_s_gain(struct v4l2_subdev * sd,int value)1242 static int ov7670_s_gain(struct v4l2_subdev *sd, int value)
1243 {
1244 	int ret;
1245 	unsigned char com8;
1246 
1247 	ret = ov7670_write(sd, REG_GAIN, value & 0xff);
1248 	/* Have to turn off AGC as well */
1249 	if (ret == 0) {
1250 		ret = ov7670_read(sd, REG_COM8, &com8);
1251 		ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
1252 	}
1253 	return ret;
1254 }
1255 
1256 /*
1257  * Tweak autogain.
1258  */
ov7670_g_autogain(struct v4l2_subdev * sd,__s32 * value)1259 static int ov7670_g_autogain(struct v4l2_subdev *sd, __s32 *value)
1260 {
1261 	int ret;
1262 	unsigned char com8;
1263 
1264 	ret = ov7670_read(sd, REG_COM8, &com8);
1265 	*value = (com8 & COM8_AGC) != 0;
1266 	return ret;
1267 }
1268 
ov7670_s_autogain(struct v4l2_subdev * sd,int value)1269 static int ov7670_s_autogain(struct v4l2_subdev *sd, int value)
1270 {
1271 	int ret;
1272 	unsigned char com8;
1273 
1274 	ret = ov7670_read(sd, REG_COM8, &com8);
1275 	if (ret == 0) {
1276 		if (value)
1277 			com8 |= COM8_AGC;
1278 		else
1279 			com8 &= ~COM8_AGC;
1280 		ret = ov7670_write(sd, REG_COM8, com8);
1281 	}
1282 	return ret;
1283 }
1284 
1285 /*
1286  * Exposure is spread all over the place: top 6 bits in AECHH, middle
1287  * 8 in AECH, and two stashed in COM1 just for the hell of it.
1288  */
ov7670_g_exp(struct v4l2_subdev * sd,__s32 * value)1289 static int ov7670_g_exp(struct v4l2_subdev *sd, __s32 *value)
1290 {
1291 	int ret;
1292 	unsigned char com1, aech, aechh;
1293 
1294 	ret = ov7670_read(sd, REG_COM1, &com1) +
1295 		ov7670_read(sd, REG_AECH, &aech) +
1296 		ov7670_read(sd, REG_AECHH, &aechh);
1297 	*value = ((aechh & 0x3f) << 10) | (aech << 2) | (com1 & 0x03);
1298 	return ret;
1299 }
1300 
ov7670_s_exp(struct v4l2_subdev * sd,int value)1301 static int ov7670_s_exp(struct v4l2_subdev *sd, int value)
1302 {
1303 	int ret;
1304 	unsigned char com1, com8, aech, aechh;
1305 
1306 	ret = ov7670_read(sd, REG_COM1, &com1) +
1307 		ov7670_read(sd, REG_COM8, &com8);
1308 		ov7670_read(sd, REG_AECHH, &aechh);
1309 	if (ret)
1310 		return ret;
1311 
1312 	com1 = (com1 & 0xfc) | (value & 0x03);
1313 	aech = (value >> 2) & 0xff;
1314 	aechh = (aechh & 0xc0) | ((value >> 10) & 0x3f);
1315 	ret = ov7670_write(sd, REG_COM1, com1) +
1316 		ov7670_write(sd, REG_AECH, aech) +
1317 		ov7670_write(sd, REG_AECHH, aechh);
1318 	/* Have to turn off AEC as well */
1319 	if (ret == 0)
1320 		ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AEC);
1321 	return ret;
1322 }
1323 
1324 /*
1325  * Tweak autoexposure.
1326  */
ov7670_g_autoexp(struct v4l2_subdev * sd,__s32 * value)1327 static int ov7670_g_autoexp(struct v4l2_subdev *sd, __s32 *value)
1328 {
1329 	int ret;
1330 	unsigned char com8;
1331 	enum v4l2_exposure_auto_type *atype = (enum v4l2_exposure_auto_type *) value;
1332 
1333 	ret = ov7670_read(sd, REG_COM8, &com8);
1334 	if (com8 & COM8_AEC)
1335 		*atype = V4L2_EXPOSURE_AUTO;
1336 	else
1337 		*atype = V4L2_EXPOSURE_MANUAL;
1338 	return ret;
1339 }
1340 
ov7670_s_autoexp(struct v4l2_subdev * sd,enum v4l2_exposure_auto_type value)1341 static int ov7670_s_autoexp(struct v4l2_subdev *sd,
1342 		enum v4l2_exposure_auto_type value)
1343 {
1344 	int ret;
1345 	unsigned char com8;
1346 
1347 	ret = ov7670_read(sd, REG_COM8, &com8);
1348 	if (ret == 0) {
1349 		if (value == V4L2_EXPOSURE_AUTO)
1350 			com8 |= COM8_AEC;
1351 		else
1352 			com8 &= ~COM8_AEC;
1353 		ret = ov7670_write(sd, REG_COM8, com8);
1354 	}
1355 	return ret;
1356 }
1357 
1358 
1359 
ov7670_queryctrl(struct v4l2_subdev * sd,struct v4l2_queryctrl * qc)1360 static int ov7670_queryctrl(struct v4l2_subdev *sd,
1361 		struct v4l2_queryctrl *qc)
1362 {
1363 	/* Fill in min, max, step and default value for these controls. */
1364 	switch (qc->id) {
1365 	case V4L2_CID_BRIGHTNESS:
1366 		return v4l2_ctrl_query_fill(qc, 0, 255, 1, 128);
1367 	case V4L2_CID_CONTRAST:
1368 		return v4l2_ctrl_query_fill(qc, 0, 127, 1, 64);
1369 	case V4L2_CID_VFLIP:
1370 	case V4L2_CID_HFLIP:
1371 		return v4l2_ctrl_query_fill(qc, 0, 1, 1, 0);
1372 	case V4L2_CID_SATURATION:
1373 		return v4l2_ctrl_query_fill(qc, 0, 256, 1, 128);
1374 	case V4L2_CID_HUE:
1375 		return v4l2_ctrl_query_fill(qc, -180, 180, 5, 0);
1376 	case V4L2_CID_GAIN:
1377 		return v4l2_ctrl_query_fill(qc, 0, 255, 1, 128);
1378 	case V4L2_CID_AUTOGAIN:
1379 		return v4l2_ctrl_query_fill(qc, 0, 1, 1, 1);
1380 	case V4L2_CID_EXPOSURE:
1381 		return v4l2_ctrl_query_fill(qc, 0, 65535, 1, 500);
1382 	case V4L2_CID_EXPOSURE_AUTO:
1383 		return v4l2_ctrl_query_fill(qc, 0, 1, 1, 0);
1384 	}
1385 	return -EINVAL;
1386 }
1387 
ov7670_g_ctrl(struct v4l2_subdev * sd,struct v4l2_control * ctrl)1388 static int ov7670_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
1389 {
1390 	switch (ctrl->id) {
1391 	case V4L2_CID_BRIGHTNESS:
1392 		return ov7670_g_brightness(sd, &ctrl->value);
1393 	case V4L2_CID_CONTRAST:
1394 		return ov7670_g_contrast(sd, &ctrl->value);
1395 	case V4L2_CID_SATURATION:
1396 		return ov7670_g_sat(sd, &ctrl->value);
1397 	case V4L2_CID_HUE:
1398 		return ov7670_g_hue(sd, &ctrl->value);
1399 	case V4L2_CID_VFLIP:
1400 		return ov7670_g_vflip(sd, &ctrl->value);
1401 	case V4L2_CID_HFLIP:
1402 		return ov7670_g_hflip(sd, &ctrl->value);
1403 	case V4L2_CID_GAIN:
1404 		return ov7670_g_gain(sd, &ctrl->value);
1405 	case V4L2_CID_AUTOGAIN:
1406 		return ov7670_g_autogain(sd, &ctrl->value);
1407 	case V4L2_CID_EXPOSURE:
1408 		return ov7670_g_exp(sd, &ctrl->value);
1409 	case V4L2_CID_EXPOSURE_AUTO:
1410 		return ov7670_g_autoexp(sd, &ctrl->value);
1411 	}
1412 	return -EINVAL;
1413 }
1414 
ov7670_s_ctrl(struct v4l2_subdev * sd,struct v4l2_control * ctrl)1415 static int ov7670_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
1416 {
1417 	switch (ctrl->id) {
1418 	case V4L2_CID_BRIGHTNESS:
1419 		return ov7670_s_brightness(sd, ctrl->value);
1420 	case V4L2_CID_CONTRAST:
1421 		return ov7670_s_contrast(sd, ctrl->value);
1422 	case V4L2_CID_SATURATION:
1423 		return ov7670_s_sat(sd, ctrl->value);
1424 	case V4L2_CID_HUE:
1425 		return ov7670_s_hue(sd, ctrl->value);
1426 	case V4L2_CID_VFLIP:
1427 		return ov7670_s_vflip(sd, ctrl->value);
1428 	case V4L2_CID_HFLIP:
1429 		return ov7670_s_hflip(sd, ctrl->value);
1430 	case V4L2_CID_GAIN:
1431 		return ov7670_s_gain(sd, ctrl->value);
1432 	case V4L2_CID_AUTOGAIN:
1433 		return ov7670_s_autogain(sd, ctrl->value);
1434 	case V4L2_CID_EXPOSURE:
1435 		return ov7670_s_exp(sd, ctrl->value);
1436 	case V4L2_CID_EXPOSURE_AUTO:
1437 		return ov7670_s_autoexp(sd,
1438 				(enum v4l2_exposure_auto_type) ctrl->value);
1439 	}
1440 	return -EINVAL;
1441 }
1442 
ov7670_g_chip_ident(struct v4l2_subdev * sd,struct v4l2_dbg_chip_ident * chip)1443 static int ov7670_g_chip_ident(struct v4l2_subdev *sd,
1444 		struct v4l2_dbg_chip_ident *chip)
1445 {
1446 	struct i2c_client *client = v4l2_get_subdevdata(sd);
1447 
1448 	return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_OV7670, 0);
1449 }
1450 
1451 #ifdef CONFIG_VIDEO_ADV_DEBUG
ov7670_g_register(struct v4l2_subdev * sd,struct v4l2_dbg_register * reg)1452 static int ov7670_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
1453 {
1454 	struct i2c_client *client = v4l2_get_subdevdata(sd);
1455 	unsigned char val = 0;
1456 	int ret;
1457 
1458 	if (!v4l2_chip_match_i2c_client(client, &reg->match))
1459 		return -EINVAL;
1460 	if (!capable(CAP_SYS_ADMIN))
1461 		return -EPERM;
1462 	ret = ov7670_read(sd, reg->reg & 0xff, &val);
1463 	reg->val = val;
1464 	reg->size = 1;
1465 	return ret;
1466 }
1467 
ov7670_s_register(struct v4l2_subdev * sd,struct v4l2_dbg_register * reg)1468 static int ov7670_s_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
1469 {
1470 	struct i2c_client *client = v4l2_get_subdevdata(sd);
1471 
1472 	if (!v4l2_chip_match_i2c_client(client, &reg->match))
1473 		return -EINVAL;
1474 	if (!capable(CAP_SYS_ADMIN))
1475 		return -EPERM;
1476 	ov7670_write(sd, reg->reg & 0xff, reg->val & 0xff);
1477 	return 0;
1478 }
1479 #endif
1480 
1481 /* ----------------------------------------------------------------------- */
1482 
1483 static const struct v4l2_subdev_core_ops ov7670_core_ops = {
1484 	.g_chip_ident = ov7670_g_chip_ident,
1485 	.g_ctrl = ov7670_g_ctrl,
1486 	.s_ctrl = ov7670_s_ctrl,
1487 	.queryctrl = ov7670_queryctrl,
1488 	.reset = ov7670_reset,
1489 	.init = ov7670_init,
1490 #ifdef CONFIG_VIDEO_ADV_DEBUG
1491 	.g_register = ov7670_g_register,
1492 	.s_register = ov7670_s_register,
1493 #endif
1494 };
1495 
1496 static const struct v4l2_subdev_video_ops ov7670_video_ops = {
1497 	.enum_mbus_fmt = ov7670_enum_mbus_fmt,
1498 	.try_mbus_fmt = ov7670_try_mbus_fmt,
1499 	.s_mbus_fmt = ov7670_s_mbus_fmt,
1500 	.s_parm = ov7670_s_parm,
1501 	.g_parm = ov7670_g_parm,
1502 	.enum_frameintervals = ov7670_enum_frameintervals,
1503 	.enum_framesizes = ov7670_enum_framesizes,
1504 };
1505 
1506 static const struct v4l2_subdev_ops ov7670_ops = {
1507 	.core = &ov7670_core_ops,
1508 	.video = &ov7670_video_ops,
1509 };
1510 
1511 /* ----------------------------------------------------------------------- */
1512 
ov7670_probe(struct i2c_client * client,const struct i2c_device_id * id)1513 static int ov7670_probe(struct i2c_client *client,
1514 			const struct i2c_device_id *id)
1515 {
1516 	struct v4l2_subdev *sd;
1517 	struct ov7670_info *info;
1518 	int ret;
1519 
1520 	info = kzalloc(sizeof(struct ov7670_info), GFP_KERNEL);
1521 	if (info == NULL)
1522 		return -ENOMEM;
1523 	sd = &info->sd;
1524 	v4l2_i2c_subdev_init(sd, client, &ov7670_ops);
1525 
1526 	info->clock_speed = 30; /* default: a guess */
1527 	if (client->dev.platform_data) {
1528 		struct ov7670_config *config = client->dev.platform_data;
1529 
1530 		/*
1531 		 * Must apply configuration before initializing device, because it
1532 		 * selects I/O method.
1533 		 */
1534 		info->min_width = config->min_width;
1535 		info->min_height = config->min_height;
1536 		info->use_smbus = config->use_smbus;
1537 
1538 		if (config->clock_speed)
1539 			info->clock_speed = config->clock_speed;
1540 	}
1541 
1542 	/* Make sure it's an ov7670 */
1543 	ret = ov7670_detect(sd);
1544 	if (ret) {
1545 		v4l_dbg(1, debug, client,
1546 			"chip found @ 0x%x (%s) is not an ov7670 chip.\n",
1547 			client->addr << 1, client->adapter->name);
1548 		kfree(info);
1549 		return ret;
1550 	}
1551 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
1552 			client->addr << 1, client->adapter->name);
1553 
1554 	info->fmt = &ov7670_formats[0];
1555 	info->sat = 128;	/* Review this */
1556 	info->clkrc = info->clock_speed / 30;
1557 	return 0;
1558 }
1559 
1560 
ov7670_remove(struct i2c_client * client)1561 static int ov7670_remove(struct i2c_client *client)
1562 {
1563 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
1564 
1565 	v4l2_device_unregister_subdev(sd);
1566 	kfree(to_state(sd));
1567 	return 0;
1568 }
1569 
1570 static const struct i2c_device_id ov7670_id[] = {
1571 	{ "ov7670", 0 },
1572 	{ }
1573 };
1574 MODULE_DEVICE_TABLE(i2c, ov7670_id);
1575 
1576 static struct i2c_driver ov7670_driver = {
1577 	.driver = {
1578 		.owner	= THIS_MODULE,
1579 		.name	= "ov7670",
1580 	},
1581 	.probe		= ov7670_probe,
1582 	.remove		= ov7670_remove,
1583 	.id_table	= ov7670_id,
1584 };
1585 
1586 module_i2c_driver(ov7670_driver);
1587