diff options
Diffstat (limited to 'drivers/media/video/ov7670.c')
-rw-r--r-- | drivers/media/video/ov7670.c | 1333 |
1 files changed, 1333 insertions, 0 deletions
diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c new file mode 100644 index 00000000000..5ed0adc4ca2 --- /dev/null +++ b/drivers/media/video/ov7670.c @@ -0,0 +1,1333 @@ +/* + * A V4L2 driver for OmniVision OV7670 cameras. + * + * Copyright 2006 One Laptop Per Child Association, Inc. Written + * by Jonathan Corbet with substantial inspiration from Mark + * McClelland's ovcamchip code. + * + * This file may be distributed under the terms of the GNU General + * Public License, version 2. + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/videodev.h> +#include <media/v4l2-common.h> +#include <linux/i2c.h> + + +MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>"); +MODULE_DESCRIPTION("A low-level driver for OmniVision ov7670 sensors"); +MODULE_LICENSE("GPL"); + +/* + * Basic window sizes. These probably belong somewhere more globally + * useful. + */ +#define VGA_WIDTH 640 +#define VGA_HEIGHT 480 +#define QVGA_WIDTH 320 +#define QVGA_HEIGHT 240 +#define CIF_WIDTH 352 +#define CIF_HEIGHT 288 +#define QCIF_WIDTH 176 +#define QCIF_HEIGHT 144 + +/* + * Our nominal (default) frame rate. + */ +#define OV7670_FRAME_RATE 30 + +/* + * The 7670 sits on i2c with ID 0x42 + */ +#define OV7670_I2C_ADDR 0x42 + +/* Registers */ +#define REG_GAIN 0x00 /* Gain lower 8 bits (rest in vref) */ +#define REG_BLUE 0x01 /* blue gain */ +#define REG_RED 0x02 /* red gain */ +#define REG_VREF 0x03 /* Pieces of GAIN, VSTART, VSTOP */ +#define REG_COM1 0x04 /* Control 1 */ +#define COM1_CCIR656 0x40 /* CCIR656 enable */ +#define REG_BAVE 0x05 /* U/B Average level */ +#define REG_GbAVE 0x06 /* Y/Gb Average level */ +#define REG_AECHH 0x07 /* AEC MS 5 bits */ +#define REG_RAVE 0x08 /* V/R Average level */ +#define REG_COM2 0x09 /* Control 2 */ +#define COM2_SSLEEP 0x10 /* Soft sleep mode */ +#define REG_PID 0x0a /* Product ID MSB */ +#define REG_VER 0x0b /* Product ID LSB */ +#define REG_COM3 0x0c /* Control 3 */ +#define COM3_SWAP 0x40 /* Byte swap */ +#define COM3_SCALEEN 0x08 /* Enable scaling */ +#define COM3_DCWEN 0x04 /* Enable downsamp/crop/window */ +#define REG_COM4 0x0d /* Control 4 */ +#define REG_COM5 0x0e /* All "reserved" */ +#define REG_COM6 0x0f /* Control 6 */ +#define REG_AECH 0x10 /* More bits of AEC value */ +#define REG_CLKRC 0x11 /* Clocl control */ +#define CLK_EXT 0x40 /* Use external clock directly */ +#define CLK_SCALE 0x3f /* Mask for internal clock scale */ +#define REG_COM7 0x12 /* Control 7 */ +#define COM7_RESET 0x80 /* Register reset */ +#define COM7_FMT_MASK 0x38 +#define COM7_FMT_VGA 0x00 +#define COM7_FMT_CIF 0x20 /* CIF format */ +#define COM7_FMT_QVGA 0x10 /* QVGA format */ +#define COM7_FMT_QCIF 0x08 /* QCIF format */ +#define COM7_RGB 0x04 /* bits 0 and 2 - RGB format */ +#define COM7_YUV 0x00 /* YUV */ +#define COM7_BAYER 0x01 /* Bayer format */ +#define COM7_PBAYER 0x05 /* "Processed bayer" */ +#define REG_COM8 0x13 /* Control 8 */ +#define COM8_FASTAEC 0x80 /* Enable fast AGC/AEC */ +#define COM8_AECSTEP 0x40 /* Unlimited AEC step size */ +#define COM8_BFILT 0x20 /* Band filter enable */ +#define COM8_AGC 0x04 /* Auto gain enable */ +#define COM8_AWB 0x02 /* White balance enable */ +#define COM8_AEC 0x01 /* Auto exposure enable */ +#define REG_COM9 0x14 /* Control 9 - gain ceiling */ +#define REG_COM10 0x15 /* Control 10 */ +#define COM10_HSYNC 0x40 /* HSYNC instead of HREF */ +#define COM10_PCLK_HB 0x20 /* Suppress PCLK on horiz blank */ +#define COM10_HREF_REV 0x08 /* Reverse HREF */ +#define COM10_VS_LEAD 0x04 /* VSYNC on clock leading edge */ +#define COM10_VS_NEG 0x02 /* VSYNC negative */ +#define COM10_HS_NEG 0x01 /* HSYNC negative */ +#define REG_HSTART 0x17 /* Horiz start high bits */ +#define REG_HSTOP 0x18 /* Horiz stop high bits */ +#define REG_VSTART 0x19 /* Vert start high bits */ +#define REG_VSTOP 0x1a /* Vert stop high bits */ +#define REG_PSHFT 0x1b /* Pixel delay after HREF */ +#define REG_MIDH 0x1c /* Manuf. ID high */ +#define REG_MIDL 0x1d /* Manuf. ID low */ +#define REG_MVFP 0x1e /* Mirror / vflip */ +#define MVFP_MIRROR 0x20 /* Mirror image */ +#define MVFP_FLIP 0x10 /* Vertical flip */ + +#define REG_AEW 0x24 /* AGC upper limit */ +#define REG_AEB 0x25 /* AGC lower limit */ +#define REG_VPT 0x26 /* AGC/AEC fast mode op region */ +#define REG_HSYST 0x30 /* HSYNC rising edge delay */ +#define REG_HSYEN 0x31 /* HSYNC falling edge delay */ +#define REG_HREF 0x32 /* HREF pieces */ +#define REG_TSLB 0x3a /* lots of stuff */ +#define TSLB_YLAST 0x04 /* UYVY or VYUY - see com13 */ +#define REG_COM11 0x3b /* Control 11 */ +#define COM11_NIGHT 0x80 /* NIght mode enable */ +#define COM11_NMFR 0x60 /* Two bit NM frame rate */ +#define COM11_HZAUTO 0x10 /* Auto detect 50/60 Hz */ +#define COM11_50HZ 0x08 /* Manual 50Hz select */ +#define COM11_EXP 0x02 +#define REG_COM12 0x3c /* Control 12 */ +#define COM12_HREF 0x80 /* HREF always */ +#define REG_COM13 0x3d /* Control 13 */ +#define COM13_GAMMA 0x80 /* Gamma enable */ +#define COM13_UVSAT 0x40 /* UV saturation auto adjustment */ +#define COM13_UVSWAP 0x01 /* V before U - w/TSLB */ +#define REG_COM14 0x3e /* Control 14 */ +#define COM14_DCWEN 0x10 /* DCW/PCLK-scale enable */ +#define REG_EDGE 0x3f /* Edge enhancement factor */ +#define REG_COM15 0x40 /* Control 15 */ +#define COM15_R10F0 0x00 /* Data range 10 to F0 */ +#define COM15_R01FE 0x80 /* 01 to FE */ +#define COM15_R00FF 0xc0 /* 00 to FF */ +#define COM15_RGB565 0x10 /* RGB565 output */ +#define COM15_RGB555 0x30 /* RGB555 output */ +#define REG_COM16 0x41 /* Control 16 */ +#define COM16_AWBGAIN 0x08 /* AWB gain enable */ +#define REG_COM17 0x42 /* Control 17 */ +#define COM17_AECWIN 0xc0 /* AEC window - must match COM4 */ +#define COM17_CBAR 0x08 /* DSP Color bar */ + +/* + * This matrix defines how the colors are generated, must be + * tweaked to adjust hue and saturation. + * + * Order: v-red, v-green, v-blue, u-red, u-green, u-blue + * + * They are nine-bit signed quantities, with the sign bit + * stored in 0x58. Sign for v-red is bit 0, and up from there. + */ +#define REG_CMATRIX_BASE 0x4f +#define CMATRIX_LEN 6 +#define REG_CMATRIX_SIGN 0x58 + + +#define REG_BRIGHT 0x55 /* Brightness */ +#define REG_CONTRAS 0x56 /* Contrast control */ + +#define REG_GFIX 0x69 /* Fix gain control */ + +#define REG_RGB444 0x8c /* RGB 444 control */ +#define R444_ENABLE 0x02 /* Turn on RGB444, overrides 5x5 */ +#define R444_RGBX 0x01 /* Empty nibble at end */ + +#define REG_HAECC1 0x9f /* Hist AEC/AGC control 1 */ +#define REG_HAECC2 0xa0 /* Hist AEC/AGC control 2 */ + +#define REG_BD50MAX 0xa5 /* 50hz banding step limit */ +#define REG_HAECC3 0xa6 /* Hist AEC/AGC control 3 */ +#define REG_HAECC4 0xa7 /* Hist AEC/AGC control 4 */ +#define REG_HAECC5 0xa8 /* Hist AEC/AGC control 5 */ +#define REG_HAECC6 0xa9 /* Hist AEC/AGC control 6 */ +#define REG_HAECC7 0xaa /* Hist AEC/AGC control 7 */ +#define REG_BD60MAX 0xab /* 60hz banding step limit */ + + +/* + * Information we maintain about a known sensor. + */ +struct ov7670_format_struct; /* coming later */ +struct ov7670_info { + struct ov7670_format_struct *fmt; /* Current format */ + unsigned char sat; /* Saturation value */ + int hue; /* Hue value */ +}; + + + + +/* + * The default register settings, as obtained from OmniVision. There + * is really no making sense of most of these - lots of "reserved" values + * and such. + * + * These settings give VGA YUYV. + */ + +struct regval_list { + unsigned char reg_num; + unsigned char value; +}; + +static struct regval_list ov7670_default_regs[] = { + { REG_COM7, COM7_RESET }, +/* + * Clock scale: 3 = 15fps + * 2 = 20fps + * 1 = 30fps + */ + { REG_CLKRC, 0x1 }, /* OV: clock scale (30 fps) */ + { REG_TSLB, 0x04 }, /* OV */ + { REG_COM7, 0 }, /* VGA */ + /* + * Set the hardware window. These values from OV don't entirely + * make sense - hstop is less than hstart. But they work... + */ + { REG_HSTART, 0x13 }, { REG_HSTOP, 0x01 }, + { REG_HREF, 0xb6 }, { REG_VSTART, 0x02 }, + { REG_VSTOP, 0x7a }, { REG_VREF, 0x0a }, + + { REG_COM3, 0 }, { REG_COM14, 0 }, + /* Mystery scaling numbers */ + { 0x70, 0x3a }, { 0x71, 0x35 }, + { 0x72, 0x11 }, { 0x73, 0xf0 }, + { 0xa2, 0x02 }, { REG_COM10, 0x0 }, + + /* Gamma curve values */ + { 0x7a, 0x20 }, { 0x7b, 0x10 }, + { 0x7c, 0x1e }, { 0x7d, 0x35 }, + { 0x7e, 0x5a }, { 0x7f, 0x69 }, + { 0x80, 0x76 }, { 0x81, 0x80 }, + { 0x82, 0x88 }, { 0x83, 0x8f }, + { 0x84, 0x96 }, { 0x85, 0xa3 }, + { 0x86, 0xaf }, { 0x87, 0xc4 }, + { 0x88, 0xd7 }, { 0x89, 0xe8 }, + + /* AGC and AEC parameters. Note we start by disabling those features, + then turn them only after tweaking the values. */ + { REG_COM8, COM8_FASTAEC | COM8_AECSTEP | COM8_BFILT }, + { REG_GAIN, 0 }, { REG_AECH, 0 }, + { REG_COM4, 0x40 }, /* magic reserved bit */ + { REG_COM9, 0x18 }, /* 4x gain + magic rsvd bit */ + { REG_BD50MAX, 0x05 }, { REG_BD60MAX, 0x07 }, + { REG_AEW, 0x95 }, { REG_AEB, 0x33 }, + { REG_VPT, 0xe3 }, { REG_HAECC1, 0x78 }, + { REG_HAECC2, 0x68 }, { 0xa1, 0x03 }, /* magic */ + { REG_HAECC3, 0xd8 }, { REG_HAECC4, 0xd8 }, + { REG_HAECC5, 0xf0 }, { REG_HAECC6, 0x90 }, + { REG_HAECC7, 0x94 }, + { REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC }, + + /* Almost all of these are magic "reserved" values. */ + { REG_COM5, 0x61 }, { REG_COM6, 0x4b }, + { 0x16, 0x02 }, { REG_MVFP, 0x07|MVFP_MIRROR }, + { 0x21, 0x02 }, { 0x22, 0x91 }, + { 0x29, 0x07 }, { 0x33, 0x0b }, + { 0x35, 0x0b }, { 0x37, 0x1d }, + { 0x38, 0x71 }, { 0x39, 0x2a }, + { REG_COM12, 0x78 }, { 0x4d, 0x40 }, + { 0x4e, 0x20 }, { REG_GFIX, 0 }, + { 0x6b, 0x4a }, { 0x74, 0x10 }, + { 0x8d, 0x4f }, { 0x8e, 0 }, + { 0x8f, 0 }, { 0x90, 0 }, + { 0x91, 0 }, { 0x96, 0 }, + { 0x9a, 0 }, { 0xb0, 0x84 }, + { 0xb1, 0x0c }, { 0xb2, 0x0e }, + { 0xb3, 0x82 }, { 0xb8, 0x0a }, + + /* More reserved magic, some of which tweaks white balance */ + { 0x43, 0x0a }, { 0x44, 0xf0 }, + { 0x45, 0x34 }, { 0x46, 0x58 }, + { 0x47, 0x28 }, { 0x48, 0x3a }, + { 0x59, 0x88 }, { 0x5a, 0x88 }, + { 0x5b, 0x44 }, { 0x5c, 0x67 }, + { 0x5d, 0x49 }, { 0x5e, 0x0e }, + { 0x6c, 0x0a }, { 0x6d, 0x55 }, + { 0x6e, 0x11 }, { 0x6f, 0x9f }, /* "9e for advance AWB" */ + { 0x6a, 0x40 }, { REG_BLUE, 0x40 }, + { REG_RED, 0x60 }, + { REG_COM8, COM8_FASTAEC|COM8_AECSTEP|COM8_BFILT|COM8_AGC|COM8_AEC|COM8_AWB }, + + /* Matrix coefficients */ + { 0x4f, 0x80 }, { 0x50, 0x80 }, + { 0x51, 0 }, { 0x52, 0x22 }, + { 0x53, 0x5e }, { 0x54, 0x80 }, + { 0x58, 0x9e }, + + { REG_COM16, COM16_AWBGAIN }, { REG_EDGE, 0 }, + { 0x75, 0x05 }, { 0x76, 0xe1 }, + { 0x4c, 0 }, { 0x77, 0x01 }, + { REG_COM13, 0xc3 }, { 0x4b, 0x09 }, + { 0xc9, 0x60 }, { REG_COM16, 0x38 }, + { 0x56, 0x40 }, + + { 0x34, 0x11 }, { REG_COM11, COM11_EXP|COM11_HZAUTO }, + { 0xa4, 0x88 }, { 0x96, 0 }, + { 0x97, 0x30 }, { 0x98, 0x20 }, + { 0x99, 0x30 }, { 0x9a, 0x84 }, + { 0x9b, 0x29 }, { 0x9c, 0x03 }, + { 0x9d, 0x4c }, { 0x9e, 0x3f }, + { 0x78, 0x04 }, + + /* Extra-weird stuff. Some sort of multiplexor register */ + { 0x79, 0x01 }, { 0xc8, 0xf0 }, + { 0x79, 0x0f }, { 0xc8, 0x00 }, + { 0x79, 0x10 }, { 0xc8, 0x7e }, + { 0x79, 0x0a }, { 0xc8, 0x80 }, + { 0x79, 0x0b }, { 0xc8, 0x01 }, + { 0x79, 0x0c }, { 0xc8, 0x0f }, + { 0x79, 0x0d }, { 0xc8, 0x20 }, + { 0x79, 0x09 }, { 0xc8, 0x80 }, + { 0x79, 0x02 }, { 0xc8, 0xc0 }, + { 0x79, 0x03 }, { 0xc8, 0x40 }, + { 0x79, 0x05 }, { 0xc8, 0x30 }, + { 0x79, 0x26 }, + + { 0xff, 0xff }, /* END MARKER */ +}; + + +/* + * Here we'll try to encapsulate the changes for just the output + * video format. + * + * RGB656 and YUV422 come from OV; RGB444 is homebrewed. + * + * IMPORTANT RULE: the first entry must be for COM7, see ov7670_s_fmt for why. + */ + + +static struct regval_list ov7670_fmt_yuv422[] = { + { REG_COM7, 0x0 }, /* Selects YUV mode */ + { REG_RGB444, 0 }, /* No RGB444 please */ + { REG_COM1, 0 }, + { REG_COM15, COM15_R00FF }, + { REG_COM9, 0x18 }, /* 4x gain ceiling; 0x8 is reserved bit */ + { 0x4f, 0x80 }, /* "matrix coefficient 1" */ + { 0x50, 0x80 }, /* "matrix coefficient 2" */ + { 0x51, 0 }, /* vb */ + { 0x52, 0x22 }, /* "matrix coefficient 4" */ + { 0x53, 0x5e }, /* "matrix coefficient 5" */ + { 0x54, 0x80 }, /* "matrix coefficient 6" */ + { REG_COM13, COM13_GAMMA|COM13_UVSAT }, + { 0xff, 0xff }, +}; + +static struct regval_list ov7670_fmt_rgb565[] = { + { REG_COM7, COM7_RGB }, /* Selects RGB mode */ + { REG_RGB444, 0 }, /* No RGB444 please */ + { REG_COM1, 0x0 }, + { REG_COM15, COM15_RGB565 }, + { REG_COM9, 0x38 }, /* 16x gain ceiling; 0x8 is reserved bit */ + { 0x4f, 0xb3 }, /* "matrix coefficient 1" */ + { 0x50, 0xb3 }, /* "matrix coefficient 2" */ + { 0x51, 0 }, /* vb */ + { 0x52, 0x3d }, /* "matrix coefficient 4" */ + { 0x53, 0xa7 }, /* "matrix coefficient 5" */ + { 0x54, 0xe4 }, /* "matrix coefficient 6" */ + { REG_COM13, COM13_GAMMA|COM13_UVSAT }, + { 0xff, 0xff }, +}; + +static struct regval_list ov7670_fmt_rgb444[] = { + { REG_COM7, COM7_RGB }, /* Selects RGB mode */ + { REG_RGB444, R444_ENABLE }, /* Enable xxxxrrrr ggggbbbb */ + { REG_COM1, 0x40 }, /* Magic reserved bit */ + { REG_COM15, COM15_R01FE|COM15_RGB565 }, /* Data range needed? */ + { REG_COM9, 0x38 }, /* 16x gain ceiling; 0x8 is reserved bit */ + { 0x4f, 0xb3 }, /* "matrix coefficient 1" */ + { 0x50, 0xb3 }, /* "matrix coefficient 2" */ + { 0x51, 0 }, /* vb */ + { 0x52, 0x3d }, /* "matrix coefficient 4" */ + { 0x53, 0xa7 }, /* "matrix coefficient 5" */ + { 0x54, 0xe4 }, /* "matrix coefficient 6" */ + { REG_COM13, COM13_GAMMA|COM13_UVSAT|0x2 }, /* Magic rsvd bit */ + { 0xff, 0xff }, +}; + + + + +/* + * Low-level register I/O. + */ + +static int ov7670_read(struct i2c_client *c, unsigned char reg, + unsigned char *value) +{ + int ret; + + ret = i2c_smbus_read_byte_data(c, reg); + if (ret >= 0) + *value = (unsigned char) ret; + return ret; +} + + +static int ov7670_write(struct i2c_client *c, unsigned char reg, + unsigned char value) +{ + return i2c_smbus_write_byte_data(c, reg, value); +} + + +/* + * Write a list of register settings; ff/ff stops the process. + */ +static int ov7670_write_array(struct i2c_client *c, struct regval_list *vals) +{ + while (vals->reg_num != 0xff || vals->value != 0xff) { + int ret = ov7670_write(c, vals->reg_num, vals->value); + if (ret < 0) + return ret; + vals++; + } + return 0; +} + + +/* + * Stuff that knows about the sensor. + */ +static void ov7670_reset(struct i2c_client *client) +{ + ov7670_write(client, REG_COM7, COM7_RESET); + msleep(1); +} + + +static int ov7670_init(struct i2c_client *client) +{ + return ov7670_write_array(client, ov7670_default_regs); +} + + + +static int ov7670_detect(struct i2c_client *client) +{ + unsigned char v; + int ret; + + ret = ov7670_init(client); + if (ret < 0) + return ret; + ret = ov7670_read(client, REG_MIDH, &v); + if (ret < 0) + return ret; + if (v != 0x7f) /* OV manuf. id. */ + return -ENODEV; + ret = ov7670_read(client, REG_MIDL, &v); + if (ret < 0) + return ret; + if (v != 0xa2) + return -ENODEV; + /* + * OK, we know we have an OmniVision chip...but which one? + */ + ret = ov7670_read(client, REG_PID, &v); + if (ret < 0) + return ret; + if (v != 0x76) /* PID + VER = 0x76 / 0x73 */ + return -ENODEV; + ret = ov7670_read(client, REG_VER, &v); + if (ret < 0) + return ret; + if (v != 0x73) /* PID + VER = 0x76 / 0x73 */ + return -ENODEV; + return 0; +} + + +/* + * Store information about the video data format. The color matrix + * is deeply tied into the format, so keep the relevant values here. + * The magic matrix nubmers come from OmniVision. + */ +static struct ov7670_format_struct { + __u8 *desc; + __u32 pixelformat; + struct regval_list *regs; + int cmatrix[CMATRIX_LEN]; +} ov7670_formats[] = { + { + .desc = "YUYV 4:2:2", + .pixelformat = V4L2_PIX_FMT_YUYV, + .regs = ov7670_fmt_yuv422, + .cmatrix = { 128, -128, 0, -34, -94, 128 }, + }, + { + .desc = "RGB 444", + .pixelformat = V4L2_PIX_FMT_RGB444, + .regs = ov7670_fmt_rgb444, + .cmatrix = { 179, -179, 0, -61, -176, 228 }, + }, + { + .desc = "RGB 565", + .pixelformat = V4L2_PIX_FMT_RGB565, + .regs = ov7670_fmt_rgb565, + .cmatrix = { 179, -179, 0, -61, -176, 228 }, + }, +}; +#define N_OV7670_FMTS (sizeof(ov7670_formats)/sizeof(ov7670_formats[0])) + +/* + * All formats we support are 2 bytes/pixel. + */ +#define BYTES_PER_PIXEL 2 + +/* + * Then there is the issue of window sizes. Try to capture the info here. + */ + +/* + * QCIF mode is done (by OV) in a very strange way - it actually looks like + * VGA with weird scaling options - they do *not* use the canned QCIF mode + * which is allegedly provided by the sensor. So here's the weird register + * settings. + */ +static struct regval_list ov7670_qcif_regs[] = { + { REG_COM3, COM3_SCALEEN|COM3_DCWEN }, + { REG_COM3, COM3_DCWEN }, + { REG_COM14, COM14_DCWEN | 0x01}, + { 0x73, 0xf1 }, + { 0xa2, 0x52 }, + { 0x7b, 0x1c }, + { 0x7c, 0x28 }, + { 0x7d, 0x3c }, + { 0x7f, 0x69 }, + { REG_COM9, 0x38 }, + { 0xa1, 0x0b }, + { 0x74, 0x19 }, + { 0x9a, 0x80 }, + { 0x43, 0x14 }, + { REG_COM13, 0xc0 }, + { 0xff, 0xff }, +}; + +static struct ov7670_win_size { + int width; + int height; + unsigned char com7_bit; + int hstart; /* Start/stop values for the camera. Note */ + int hstop; /* that they do not always make complete */ + int vstart; /* sense to humans, but evidently the sensor */ + int vstop; /* will do the right thing... */ + struct regval_list *regs; /* Regs to tweak */ +/* h/vref stuff */ +} ov7670_win_sizes[] = { + /* VGA */ + { + .width = VGA_WIDTH, + .height = VGA_HEIGHT, + .com7_bit = COM7_FMT_VGA, + .hstart = 158, /* These values from */ + .hstop = 14, /* Omnivision */ + .vstart = 10, + .vstop = 490, + .regs = NULL, + }, + /* CIF */ + { + .width = CIF_WIDTH, + .height = CIF_HEIGHT, + .com7_bit = COM7_FMT_CIF, + .hstart = 170, /* Empirically determined */ + .hstop = 90, + .vstart = 14, + .vstop = 494, + .regs = NULL, + }, + /* QVGA */ + { + .width = QVGA_WIDTH, + .height = QVGA_HEIGHT, + .com7_bit = COM7_FMT_QVGA, + .hstart = 164, /* Empirically determined */ + .hstop = 20, + .vstart = 14, + .vstop = 494, + .regs = NULL, + }, + /* QCIF */ + { + .width = QCIF_WIDTH, + .height = QCIF_HEIGHT, + .com7_bit = COM7_FMT_VGA, /* see comment above */ + .hstart = 456, /* Empirically determined */ + .hstop = 24, + .vstart = 14, + .vstop = 494, + .regs = ov7670_qcif_regs, + }, +}; + +#define N_WIN_SIZES (sizeof(ov7670_win_sizes)/sizeof(ov7670_win_sizes[0])) + + +/* + * Store a set of start/stop values into the camera. + */ +static int ov7670_set_hw(struct i2c_client *client, int hstart, int hstop, + int vstart, int vstop) +{ + int ret; + unsigned char v; +/* + * Horizontal: 11 bits, top 8 live in hstart and hstop. Bottom 3 of + * hstart are in href[2:0], bottom 3 of hstop in href[5:3]. There is + * a mystery "edge offset" value in the top two bits of href. + */ + ret = ov7670_write(client, REG_HSTART, (hstart >> 3) & 0xff); + ret += ov7670_write(client, REG_HSTOP, (hstop >> 3) & 0xff); + ret += ov7670_read(client, REG_HREF, &v); + v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7); + msleep(10); + ret += ov7670_write(client, REG_HREF, v); +/* + * Vertical: similar arrangement, but only 10 bits. + */ + ret += ov7670_write(client, REG_VSTART, (vstart >> 2) & 0xff); + ret += ov7670_write(client, REG_VSTOP, (vstop >> 2) & 0xff); + ret += ov7670_read(client, REG_VREF, &v); + v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3); + msleep(10); + ret += ov7670_write(client, REG_VREF, v); + return ret; +} + + +static int ov7670_enum_fmt(struct i2c_client *c, struct v4l2_fmtdesc *fmt) +{ + struct ov7670_format_struct *ofmt; + + if (fmt->index >= N_OV7670_FMTS) + return -EINVAL; + + ofmt = ov7670_formats + fmt->index; + fmt->flags = 0; + strcpy(fmt->description, ofmt->desc); + fmt->pixelformat = ofmt->pixelformat; + return 0; +} + + +static int ov7670_try_fmt(struct i2c_client *c, struct v4l2_format *fmt, + struct ov7670_format_struct **ret_fmt, + struct ov7670_win_size **ret_wsize) +{ + int index; + struct ov7670_win_size *wsize; + struct v4l2_pix_format *pix = &fmt->fmt.pix; + + for (index = 0; index < N_OV7670_FMTS; index++) + if (ov7670_formats[index].pixelformat == pix->pixelformat) + break; + if (index >= N_OV7670_FMTS) + return -EINVAL; + if (ret_fmt != NULL) + *ret_fmt = ov7670_formats + index; + /* + * Fields: the OV devices claim to be progressive. + */ + if (pix->field == V4L2_FIELD_ANY) + pix->field = V4L2_FIELD_NONE; + else if (pix->field != V4L2_FIELD_NONE) + return -EINVAL; + /* + * Round requested image size down to the nearest + * we support, but not below the smallest. + */ + for (wsize = ov7670_win_sizes; wsize < ov7670_win_sizes + N_WIN_SIZES; + wsize++) + if (pix->width >= wsize->width && pix->height >= wsize->height) + break; + if (wsize >= ov7670_win_sizes + N_WIN_SIZES) + wsize--; /* Take the smallest one */ + if (ret_wsize != NULL) + *ret_wsize = wsize; + /* + * Note the size we'll actually handle. + */ + pix->width = wsize->width; + pix->height = wsize->height; + pix->bytesperline = pix->width*BYTES_PER_PIXEL; + pix->sizeimage = pix->height*pix->bytesperline; + return 0; +} + +/* + * Set a format. + */ +static int ov7670_s_fmt(struct i2c_client *c, struct v4l2_format *fmt) +{ + int ret; + struct ov7670_format_struct *ovfmt; + struct ov7670_win_size *wsize; + struct ov7670_info *info = i2c_get_clientdata(c); + unsigned char com7; + + ret = ov7670_try_fmt(c, fmt, &ovfmt, &wsize); + if (ret) + return ret; + /* + * COM7 is a pain in the ass, it doesn't like to be read then + * quickly written afterward. But we have everything we need + * to set it absolutely here, as long as the format-specific + * register sets list it first. + */ + com7 = ovfmt->regs[0].value; + com7 |= wsize->com7_bit; + ov7670_write(c, REG_COM7, com7); + /* + * Now write the rest of the array. Also store start/stops + */ + ov7670_write_array(c, ovfmt->regs + 1); + ov7670_set_hw(c, wsize->hstart, wsize->hstop, wsize->vstart, + wsize->vstop); + ret = 0; + if (wsize->regs) + ret = ov7670_write_array(c, wsize->regs); + info->fmt = ovfmt; + return 0; +} + +/* + * Implement G/S_PARM. There is a "high quality" mode we could try + * to do someday; for now, we just do the frame rate tweak. + */ +static int ov7670_g_parm(struct i2c_client *c, struct v4l2_streamparm *parms) +{ + struct v4l2_captureparm *cp = &parms->parm.capture; + unsigned char clkrc; + int ret; + + if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) + return -EINVAL; + ret = ov7670_read(c, REG_CLKRC, &clkrc); + if (ret < 0) + return ret; + memset(cp, 0, sizeof(struct v4l2_captureparm)); + cp->capability = V4L2_CAP_TIMEPERFRAME; + cp->timeperframe.numerator = 1; + cp->timeperframe.denominator = OV7670_FRAME_RATE; + if ((clkrc & CLK_EXT) == 0 && (clkrc & CLK_SCALE) > 1) + cp->timeperframe.denominator /= (clkrc & CLK_SCALE); + return 0; +} + +static int ov7670_s_parm(struct i2c_client *c, struct v4l2_streamparm *parms) +{ + struct v4l2_captureparm *cp = &parms->parm.capture; + struct v4l2_fract *tpf = &cp->timeperframe; + unsigned char clkrc; + int ret, div; + + if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) + return -EINVAL; + if (cp->extendedmode != 0) + return -EINVAL; + /* + * CLKRC has a reserved bit, so let's preserve it. + */ + ret = ov7670_read(c, REG_CLKRC, &clkrc); + if (ret < 0) + return ret; + if (tpf->numerator == 0 || tpf->denominator == 0) + div = 1; /* Reset to full rate */ + else + div = (tpf->numerator*OV7670_FRAME_RATE)/tpf->denominator; + if (div == 0) + div = 1; + else if (div > CLK_SCALE) + div = CLK_SCALE; + clkrc = (clkrc & 0x80) | div; + tpf->numerator = 1; + tpf->denominator = OV7670_FRAME_RATE/div; + return ov7670_write(c, REG_CLKRC, clkrc); +} + + + +/* + * Code for dealing with controls. + */ + + + + + +static int ov7670_store_cmatrix(struct i2c_client *client, + int matrix[CMATRIX_LEN]) +{ + int i, ret; + unsigned char signbits; + + /* + * Weird crap seems to exist in the upper part of + * the sign bits register, so let's preserve it. + */ + ret = ov7670_read(client, REG_CMATRIX_SIGN, &signbits); + signbits &= 0xc0; + + for (i = 0; i < CMATRIX_LEN; i++) { + unsigned char raw; + + if (matrix[i] < 0) { + signbits |= (1 << i); + if (matrix[i] < -255) + raw = 0xff; + else + raw = (-1 * matrix[i]) & 0xff; + } + else { + if (matrix[i] > 255) + raw = 0xff; + else + raw = matrix[i] & 0xff; + } + ret += ov7670_write(client, REG_CMATRIX_BASE + i, raw); + } + ret += ov7670_write(client, REG_CMATRIX_SIGN, signbits); + return ret; +} + + +/* + * Hue also requires messing with the color matrix. It also requires + * trig functions, which tend not to be well supported in the kernel. + * So here is a simple table of sine values, 0-90 degrees, in steps + * of five degrees. Values are multiplied by 1000. + * + * The following naive approximate trig functions require an argument + * carefully limited to -180 <= theta <= 180. + */ +#define SIN_STEP 5 +static const int ov7670_sin_table[] = { + 0, 87, 173, 258, 342, 422, + 499, 573, 642, 707, 766, 819, + 866, 906, 939, 965, 984, 996, + 1000 +}; + +static int ov7670_sine(int theta) +{ + int chs = 1; + int sine; + + if (theta < 0) { + theta = -theta; + chs = -1; + } + if (theta <= 90) + sine = ov7670_sin_table[theta/SIN_STEP]; + else { + theta -= 90; + sine = 1000 - ov7670_sin_table[theta/SIN_STEP]; + } + return sine*chs; +} + +static int ov7670_cosine(int theta) +{ + theta = 90 - theta; + if (theta > 180) + theta -= 360; + else if (theta < -180) + theta += 360; + return ov7670_sine(theta); +} + + + + +static void ov7670_calc_cmatrix(struct ov7670_info *info, + int matrix[CMATRIX_LEN]) +{ + int i; + /* + * Apply the current saturation setting first. + */ + for (i = 0; i < CMATRIX_LEN; i++) + matrix[i] = (info->fmt->cmatrix[i]*info->sat) >> 7; + /* + * Then, if need be, rotate the hue value. + */ + if (info->hue != 0) { + int sinth, costh, tmpmatrix[CMATRIX_LEN]; + + memcpy(tmpmatrix, matrix, CMATRIX_LEN*sizeof(int)); + sinth = ov7670_sine(info->hue); + costh = ov7670_cosine(info->hue); + + matrix[0] = (matrix[3]*sinth + matrix[0]*costh)/1000; + matrix[1] = (matrix[4]*sinth + matrix[1]*costh)/1000; + matrix[2] = (matrix[5]*sinth + matrix[2]*costh)/1000; + matrix[3] = (matrix[3]*costh - matrix[0]*sinth)/1000; + matrix[4] = (matrix[4]*costh - matrix[1]*sinth)/1000; + matrix[5] = (matrix[5]*costh - matrix[2]*sinth)/1000; + } +} + + + +static int ov7670_t_sat(struct i2c_client *client, int value) +{ + struct ov7670_info *info = i2c_get_clientdata(client); + int matrix[CMATRIX_LEN]; + int ret; + + info->sat = value; + ov7670_calc_cmatrix(info, matrix); + ret = ov7670_store_cmatrix(client, matrix); + return ret; +} + +static int ov7670_q_sat(struct i2c_client *client, __s32 *value) +{ + struct ov7670_info *info = i2c_get_clientdata(client); + + *value = info->sat; + return 0; +} + +static int ov7670_t_hue(struct i2c_client *client, int value) +{ + struct ov7670_info *info = i2c_get_clientdata(client); + int matrix[CMATRIX_LEN]; + int ret; + + if (value < -180 || value > 180) + return -EINVAL; + info->hue = value; + ov7670_calc_cmatrix(info, matrix); + ret = ov7670_store_cmatrix(client, matrix); + return ret; +} + + +static int ov7670_q_hue(struct i2c_client *client, __s32 *value) +{ + struct ov7670_info *info = i2c_get_clientdata(client); + + *value = info->hue; + return 0; +} + + +/* + * Some weird registers seem to store values in a sign/magnitude format! + */ +static unsigned char ov7670_sm_to_abs(unsigned char v) +{ + if ((v & 0x80) == 0) + return v + 128; + else + return 128 - (v & 0x7f); +} + + +static unsigned char ov7670_abs_to_sm(unsigned char v) +{ + if (v > 127) + return v & 0x7f; + else + return (128 - v) | 0x80; +} + +static int ov7670_t_brightness(struct i2c_client *client, int value) +{ + unsigned char com8, v; + int ret; + + ov7670_read(client, REG_COM8, &com8); + com8 &= ~COM8_AEC; + ov7670_write(client, REG_COM8, com8); + v = ov7670_abs_to_sm(value); + ret = ov7670_write(client, REG_BRIGHT, v); + return ret; +} + +static int ov7670_q_brightness(struct i2c_client *client, __s32 *value) +{ + unsigned char v; + int ret = ov7670_read(client, REG_BRIGHT, &v); + + *value = ov7670_sm_to_abs(v); + return ret; +} + +static int ov7670_t_contrast(struct i2c_client *client, int value) +{ + return ov7670_write(client, REG_CONTRAS, (unsigned char) value); +} + +static int ov7670_q_contrast(struct i2c_client *client, __s32 *value) +{ + unsigned char v; + int ret = ov7670_read(client, REG_CONTRAS, &v); + + *value = v; + return ret; +} + +static int ov7670_q_hflip(struct i2c_client *client, __s32 *value) +{ + int ret; + unsigned char v; + + ret = ov7670_read(client, REG_MVFP, &v); + *value = (v & MVFP_MIRROR) == MVFP_MIRROR; + return ret; +} + + +static int ov7670_t_hflip(struct i2c_client *client, int value) +{ + unsigned char v; + int ret; + + ret = ov7670_read(client, REG_MVFP, &v); + if (value) + v |= MVFP_MIRROR; + else + v &= ~MVFP_MIRROR; + msleep(10); /* FIXME */ + ret += ov7670_write(client, REG_MVFP, v); + return ret; +} + + + +static int ov7670_q_vflip(struct i2c_client *client, __s32 *value) +{ + int ret; + unsigned char v; + + ret = ov7670_read(client, REG_MVFP, &v); + *value = (v & MVFP_FLIP) == MVFP_FLIP; + return ret; +} + + +static int ov7670_t_vflip(struct i2c_client *client, int value) +{ + unsigned char v; + int ret; + + ret = ov7670_read(client, REG_MVFP, &v); + if (value) + v |= MVFP_FLIP; + else + v &= ~MVFP_FLIP; + msleep(10); /* FIXME */ + ret += ov7670_write(client, REG_MVFP, v); + return ret; +} + + +static struct ov7670_control { + struct v4l2_queryctrl qc; + int (*query)(struct i2c_client *c, __s32 *value); + int (*tweak)(struct i2c_client *c, int value); +} ov7670_controls[] = +{ + { + .qc = { + .id = V4L2_CID_BRIGHTNESS, + .type = V4L2_CTRL_TYPE_INTEGER, + .name = "Brightness", + .minimum = 0, + .maximum = 255, + .step = 1, + .default_value = 0x80, + .flags = V4L2_CTRL_FLAG_SLIDER + }, + .tweak = ov7670_t_brightness, + .query = ov7670_q_brightness, + }, + { + .qc = { + .id = V4L2_CID_CONTRAST, + .type = V4L2_CTRL_TYPE_INTEGER, + .name = "Contrast", + .minimum = 0, + .maximum = 127, + .step = 1, + .default_value = 0x40, /* XXX ov7670 spec */ + .flags = V4L2_CTRL_FLAG_SLIDER + }, + .tweak = ov7670_t_contrast, + .query = ov7670_q_contrast, + }, + { + .qc = { + .id = V4L2_CID_SATURATION, + .type = V4L2_CTRL_TYPE_INTEGER, + .name = "Saturation", + .minimum = 0, + .maximum = 256, + .step = 1, + .default_value = 0x80, + .flags = V4L2_CTRL_FLAG_SLIDER + }, + .tweak = ov7670_t_sat, + .query = ov7670_q_sat, + }, + { + .qc = { + .id = V4L2_CID_HUE, + .type = V4L2_CTRL_TYPE_INTEGER, + .name = "HUE", + .minimum = -180, + .maximum = 180, + .step = 5, + .default_value = 0, + .flags = V4L2_CTRL_FLAG_SLIDER + }, + .tweak = ov7670_t_hue, + .query = ov7670_q_hue, + }, + { + .qc = { + .id = V4L2_CID_VFLIP, + .type = V4L2_CTRL_TYPE_BOOLEAN, + .name = "Vertical flip", + .minimum = 0, + .maximum = 1, + .step = 1, + .default_value = 0, + }, + .tweak = ov7670_t_vflip, + .query = ov7670_q_vflip, + }, + { + .qc = { + .id = V4L2_CID_HFLIP, + .type = V4L2_CTRL_TYPE_BOOLEAN, + .name = "Horizontal mirror", + .minimum = 0, + .maximum = 1, + .step = 1, + .default_value = 0, + }, + .tweak = ov7670_t_hflip, + .query = ov7670_q_hflip, + }, +}; +#define N_CONTROLS (sizeof(ov7670_controls)/sizeof(ov7670_controls[0])) + +static struct ov7670_control *ov7670_find_control(__u32 id) +{ + int i; + + for (i = 0; i < N_CONTROLS; i++) + if (ov7670_controls[i].qc.id == id) + return ov7670_controls + i; + return NULL; +} + + +static int ov7670_queryctrl(struct i2c_client *client, + struct v4l2_queryctrl *qc) +{ + struct ov7670_control *ctrl = ov7670_find_control(qc->id); + + if (ctrl == NULL) + return -EINVAL; + *qc = ctrl->qc; + return 0; +} + +static int ov7670_g_ctrl(struct i2c_client *client, struct v4l2_control *ctrl) +{ + struct ov7670_control *octrl = ov7670_find_control(ctrl->id); + int ret; + + if (octrl == NULL) + return -EINVAL; + ret = octrl->query(client, &ctrl->value); + if (ret >= 0) + return 0; + return ret; +} + +static int ov7670_s_ctrl(struct i2c_client *client, struct v4l2_control *ctrl) +{ + struct ov7670_control *octrl = ov7670_find_control(ctrl->id); + int ret; + + if (octrl == NULL) + return -EINVAL; + ret = octrl->tweak(client, ctrl->value); + if (ret >= 0) + return 0; + return ret; +} + + + + + + +/* + * Basic i2c stuff. + */ +static struct i2c_driver ov7670_driver; + +static int ov7670_attach(struct i2c_adapter *adapter) +{ + int ret; + struct i2c_client *client; + struct ov7670_info *info; + + /* + * For now: only deal with adapters we recognize. + */ + if (adapter->id != I2C_HW_SMBUS_CAFE) + return -ENODEV; + + client = kzalloc(sizeof (struct i2c_client), GFP_KERNEL); + if (! client) + return -ENOMEM; + client->adapter = adapter; + client->addr = OV7670_I2C_ADDR; + client->driver = &ov7670_driver, + strcpy(client->name, "OV7670"); + /* + * Set up our info structure. + */ + info = kzalloc(sizeof (struct ov7670_info), GFP_KERNEL); + if (! info) { + ret = -ENOMEM; + goto out_free; + } + info->fmt = &ov7670_formats[0]; + info->sat = 128; /* Review this */ + i2c_set_clientdata(client, info); + + /* + * Make sure it's an ov7670 + */ + ret = ov7670_detect(client); + if (ret) + goto out_free_info; + i2c_attach_client(client); + return 0; + + out_free_info: + kfree(info); + out_free: + kfree(client); + return ret; +} + + +static int ov7670_detach(struct i2c_client *client) +{ + i2c_detach_client(client); + kfree(i2c_get_clientdata(client)); + kfree(client); + return 0; +} + + +static int ov7670_command(struct i2c_client *client, unsigned int cmd, + void *arg) +{ + switch (cmd) { + case VIDIOC_INT_G_CHIP_IDENT: + * (enum v4l2_chip_ident *) arg = V4L2_IDENT_OV7670; + return 0; + + case VIDIOC_INT_RESET: + ov7670_reset(client); + return 0; + + case VIDIOC_INT_INIT: + return ov7670_init(client); + + case VIDIOC_ENUM_FMT: + return ov7670_enum_fmt(client, (struct v4l2_fmtdesc *) arg); + case VIDIOC_TRY_FMT: + return ov7670_try_fmt(client, (struct v4l2_format *) arg, NULL, NULL); + case VIDIOC_S_FMT: + return ov7670_s_fmt(client, (struct v4l2_format *) arg); + case VIDIOC_QUERYCTRL: + return ov7670_queryctrl(client, (struct v4l2_queryctrl *) arg); + case VIDIOC_S_CTRL: + return ov7670_s_ctrl(client, (struct v4l2_control *) arg); + case VIDIOC_G_CTRL: + return ov7670_g_ctrl(client, (struct v4l2_control *) arg); + case VIDIOC_S_PARM: + return ov7670_s_parm(client, (struct v4l2_streamparm *) arg); + case VIDIOC_G_PARM: + return ov7670_g_parm(client, (struct v4l2_streamparm *) arg); + } + return -EINVAL; +} + + + +static struct i2c_driver ov7670_driver = { + .driver = { + .name = "ov7670", + }, + .id = I2C_DRIVERID_OV7670, + .class = I2C_CLASS_CAM_DIGITAL, + .attach_adapter = ov7670_attach, + .detach_client = ov7670_detach, + .command = ov7670_command, +}; + + +/* + * Module initialization + */ +static int __init ov7670_mod_init(void) +{ + printk(KERN_NOTICE "OmniVision ov7670 sensor driver, at your service\n"); + return i2c_add_driver(&ov7670_driver); +} + +static void __exit ov7670_mod_exit(void) +{ + i2c_del_driver(&ov7670_driver); +} + +module_init(ov7670_mod_init); +module_exit(ov7670_mod_exit); |