/* * 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. * * Copyright 2006-7 Jonathan Corbet * * This file may be distributed under the terms of the GNU General * Public License, version 2. */ #include #include #include #include #include #include #include #include MODULE_AUTHOR("Jonathan Corbet "); 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_REG76 0x76 /* OV's name */ #define R76_BLKPCOR 0x80 /* Black pixel correction enable */ #define R76_WHTPCOR 0x40 /* White pixel correction enable */ #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 }, { 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 }, }; static struct regval_list ov7670_fmt_raw[] = { { REG_COM7, COM7_BAYER }, { REG_COM13, 0x08 }, /* No gamma, magic rsvd bit */ { REG_COM16, 0x3d }, /* Edge enhancement, denoise */ { REG_REG76, 0xe1 }, /* Pix correction, magic rsvd */ { 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) { int ret = i2c_smbus_write_byte_data(c, reg, value); if (reg == REG_COM7 && (value & COM7_RESET)) msleep(2); /* Wait for reset to run */ return ret; } /* * 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]; int bpp; /* Bytes per pixel */ } ov7670_formats[] = { { .desc = "YUYV 4:2:2", .pixelformat = V4L2_PIX_FMT_YUYV, .regs = ov7670_fmt_yuv422, .cmatrix = { 128, -128, 0, -34, -94, 128 }, .bpp = 2, }, { .desc = "RGB 444", .pixelformat = V4L2_PIX_FMT_RGB444, .regs = ov7670_fmt_rgb444, .cmatrix = { 179, -179, 0, -61, -176, 228 }, .bpp = 2, }, { .desc = "RGB 565", .pixelformat = V4L2_PIX_FMT_RGB565, .regs = ov7670_fmt_rgb565, .cmatrix = { 179, -179, 0, -61, -176, 228 }, .bpp = 2, }, { .desc = "Raw RGB Bayer", .pixelformat = V4L2_PIX_FMT_SBGGR8, .regs = ov7670_fmt_raw, .cmatrix = { 0, 0, 0, 0, 0, 0 }, .bpp = 1 }, }; #define N_OV7670_FMTS ARRAY_SIZE(ov7670_formats) /* * 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 (ARRAY_SIZE(ov7670_win_sizes)) /* * 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*ov7670_formats[index].bpp; 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, clkrc; ret = ov7670_try_fmt(c, fmt, &ovfmt, &wsize); if (ret) return ret; /* * HACK: if we're running rgb565 we need to grab then rewrite * CLKRC. If we're *not*, however, then rewriting clkrc hoses * the colors. */ if (fmt->fmt.pix.pixelformat == V4L2_PIX_FMT_RGB565) { ret = ov7670_read(c, REG_CLKRC, &clkrc); 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; if (fmt->fmt.pix.pixelformat == V4L2_PIX_FMT_RGB565 && ret == 0) ret = ov7670_write(c, REG_CLKRC, clkrc); return ret; } /* * 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 (ARRAY_SIZE(ov7670_controls)) 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; ret = i2c_attach_client(client); if (ret) goto out_free_info; 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_G_CHIP_IDENT: return v4l2_chip_ident_i2c_client(client, arg, V4L2_IDENT_OV7670, 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);