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linux/drivers/media/video/ov7670.c
Daniel Drake cd257a6f4d V4L/DVB (8318): OV7670: don't reject unsupported settings 
For VIDIOC_G_FMT/VIDIOC_TRY_FMT, the V4L2 API spec states:
"Drivers should not return an error code unless the input is ambiguous"
"Very simple, inflexible devices may even ignore all input and always
return the default parameters."
"When the requested buffer type is not supported drivers return an
EINVAL error code."
i.e. returning errors for unsupported fields is bad, and it's ok to
unconditionally overwrite user-requested settings

This patch makes ov7670 meet that behaviour, and brings it in line with
other drivers e.g. stk-webcam. It also fixes compatibility with (unpatched)
gstreamer.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-07-20 07:24:41 -03:00

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/*
* 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 <corbet@lwn.net>
*
* 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/slab.h>
#include <linux/delay.h>
#include <linux/videodev.h>
#include <media/v4l2-common.h>
#include <media/v4l2-chip-ident.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_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;
ret = 0;
}
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) {
/* default to first format */
index = 0;
pix->pixelformat = ov7670_formats[0].pixelformat;
}
if (ret_fmt != NULL)
*ret_fmt = ov7670_formats + index;
/*
* Fields: the OV devices claim to be progressive.
*/
pix->field = V4L2_FIELD_NONE;
/*
* 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);
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