// SPDX-License-Identifier: GPL-2.0-only
/*
* 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 <[email protected]>
*/
#include <linux/clk.h>
#include <linux/init.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/videodev2.h>
#include <linux/gpio/consumer.h>
#include <media/v4l2-device.h>
#include <media/v4l2-event.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-mediabus.h>
#include <media/v4l2-image-sizes.h>
#include <media/i2c/ov7670.h>
MODULE_AUTHOR("Jonathan Corbet <[email protected]>");
MODULE_DESCRIPTION("A low-level driver for OmniVision ov7670 sensors");
MODULE_LICENSE("GPL");
static bool debug;
module_param(debug, bool, 0644);
MODULE_PARM_DESC(debug, "Debug level (0-1)");
/*
* The 7670 sits on i2c with ID 0x42
*/
#define OV7670_I2C_ADDR 0x42
#define PLL_FACTOR 4
/* 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_DBLV 0x6b /* PLL control an debugging */
#define DBLV_BYPASS 0x0a /* Bypass PLL */
#define DBLV_X4 0x4a /* clock x4 */
#define DBLV_X6 0x8a /* clock x6 */
#define DBLV_X8 0xca /* clock x8 */
#define REG_SCALING_XSC 0x70 /* Test pattern and horizontal scale factor */
#define TEST_PATTTERN_0 0x80
#define REG_SCALING_YSC 0x71 /* Test pattern and vertical scale factor */
#define TEST_PATTTERN_1 0x80
#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 */
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 */
};
struct ov7670_devtype {
/* formats supported for each model */
struct ov7670_win_size *win_sizes;
unsigned int n_win_sizes;
/* callbacks for frame rate control */
int (*set_framerate)(struct v4l2_subdev *, struct v4l2_fract *);
void (*get_framerate)(struct v4l2_subdev *, struct v4l2_fract *);
};
/*
* Information we maintain about a known sensor.
*/
struct ov7670_format_struct; /* coming later */
struct ov7670_info {
struct v4l2_subdev sd;
struct media_pad pad;
struct v4l2_ctrl_handler hdl;
struct {
/* gain cluster */
struct v4l2_ctrl *auto_gain;
struct v4l2_ctrl *gain;
};
struct {
/* exposure cluster */
struct v4l2_ctrl *auto_exposure;
struct v4l2_ctrl *exposure;
};
struct {
/* saturation/hue cluster */
struct v4l2_ctrl *saturation;
struct v4l2_ctrl *hue;
};
struct v4l2_mbus_framefmt format;
struct ov7670_format_struct *fmt; /* Current format */
struct ov7670_win_size *wsize;
struct clk *clk;
int on;
struct gpio_desc *resetb_gpio;
struct gpio_desc *pwdn_gpio;
unsigned int mbus_config; /* Media bus configuration flags */
int min_width; /* Filter out smaller sizes */
int min_height; /* Filter out smaller sizes */
int clock_speed; /* External clock speed (MHz) */
u8 clkrc; /* Clock divider value */
bool use_smbus; /* Use smbus I/O instead of I2C */
bool pll_bypass;
bool pclk_hb_disable;
const struct ov7670_devtype *devtype; /* Device specifics */
};
static inline struct ov7670_info *to_state(struct v4l2_subdev *sd)
{
return container_of(sd, struct ov7670_info, sd);
}
static inline struct v4l2_subdev *to_sd(struct v4l2_ctrl *ctrl)
{
return &container_of(ctrl->handler, struct ov7670_info, hdl)->sd;
}
/*
* 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 */
{ REG_SCALING_XSC, 0x3a },
{ REG_SCALING_YSC, 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 }, /* CCIR601 */
{ REG_COM15, COM15_R00FF },
{ REG_COM9, 0x48 }, /* 32x 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 }, /* CCIR601 */
{ 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, 0x0 }, /* CCIR601 */
{ 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.
*
* Note that there are two versions of these. On the XO 1, the
* i2c controller only does SMBUS, so that's what we use. The
* ov7670 is not really an SMBUS device, though, so the communication
* is not always entirely reliable.
*/
static int ov7670_read_smbus(struct v4l2_subdev *sd, unsigned char reg,
unsigned char *value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
int ret;
ret = i2c_smbus_read_byte_data(client, reg);
if (ret >= 0) {
*value = (unsigned char)ret;
ret = 0;
}
return ret;
}
static int ov7670_write_smbus(struct v4l2_subdev *sd, unsigned char reg,
unsigned char value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
int ret = i2c_smbus_write_byte_data(client, reg, value);
if (reg == REG_COM7 && (value & COM7_RESET))
msleep(5); /* Wait for reset to run */
return ret;
}
/*
* On most platforms, we'd rather do straight i2c I/O.
*/
static int ov7670_read_i2c(struct v4l2_subdev *sd, unsigned char reg,
unsigned char *value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
u8 data = reg;
struct i2c_msg msg;
int ret;
/*
* Send out the register address...
*/
msg.addr = client->addr;
msg.flags = 0;
msg.len = 1;
msg.buf = &data;
ret = i2c_transfer(client->adapter, &msg, 1);
if (ret < 0) {
printk(KERN_ERR "Error %d on register write\n", ret);
return ret;
}
/*
* ...then read back the result.
*/
msg.flags = I2C_M_RD;
ret = i2c_transfer(client->adapter, &msg, 1);
if (ret >= 0) {
*value = data;
ret = 0;
}
return ret;
}
static int ov7670_write_i2c(struct v4l2_subdev *sd, unsigned char reg,
unsigned char value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
struct i2c_msg msg;
unsigned char data[2] = { reg, value };
int ret;
msg.addr = client->addr;
msg.flags = 0;
msg.len = 2;
msg.buf = data;
ret = i2c_transfer(client->adapter, &msg, 1);
if (ret > 0)
ret = 0;
if (reg == REG_COM7 && (value & COM7_RESET))
msleep(5); /* Wait for reset to run */
return ret;
}
static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
unsigned char *value)
{
struct ov7670_info *info = to_state(sd);
if (info->use_smbus)
return ov7670_read_smbus(sd, reg, value);
else
return ov7670_read_i2c(sd, reg, value);
}
static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
unsigned char value)
{
struct ov7670_info *info = to_state(sd);
if (info->use_smbus)
return ov7670_write_smbus(sd, reg, value);
else
return ov7670_write_i2c(sd, reg, value);
}
static int ov7670_update_bits(struct v4l2_subdev *sd, unsigned char reg,
unsigned char mask, unsigned char value)
{
unsigned char orig;
int ret;
ret = ov7670_read(sd, reg, &orig);
if (ret)
return ret;
return ov7670_write(sd, reg, (orig & ~mask) | (value & mask));
}
/*
* Write a list of register settings; ff/ff stops the process.
*/
static int ov7670_write_array(struct v4l2_subdev *sd, struct regval_list *vals)
{
while (vals->reg_num != 0xff || vals->value != 0xff) {
int ret = ov7670_write(sd, vals->reg_num, vals->value);
if (ret < 0)
return ret;
vals++;
}
return 0;
}
/*
* Stuff that knows about the sensor.
*/
static int ov7670_reset(struct v4l2_subdev *sd, u32 val)
{
ov7670_write(sd, REG_COM7, COM7_RESET);
msleep(1);
return 0;
}
static int ov7670_init(struct v4l2_subdev *sd, u32 val)
{
return ov7670_write_array(sd, ov7670_default_regs);
}
static int ov7670_detect(struct v4l2_subdev *sd)
{
unsigned char v;
int ret;
ret = ov7670_init(sd, 0);
if (ret < 0)
return ret;
ret = ov7670_read(sd, REG_MIDH, &v);
if (ret < 0)
return ret;
if (v != 0x7f) /* OV manuf. id. */
return -ENODEV;
ret = ov7670_read(sd, 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(sd, REG_PID, &v);
if (ret < 0)
return ret;
if (v != 0x76) /* PID + VER = 0x76 / 0x73 */
return -ENODEV;
ret = ov7670_read(sd, 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 numbers come from OmniVision.
*/
static struct ov7670_format_struct {
u32 mbus_code;
enum v4l2_colorspace colorspace;
struct regval_list *regs;
int cmatrix[CMATRIX_LEN];
} ov7670_formats[] = {
{
.mbus_code = MEDIA_BUS_FMT_YUYV8_2X8,
.colorspace = V4L2_COLORSPACE_SRGB,
.regs = ov7670_fmt_yuv422,
.cmatrix = { 128, -128, 0, -34, -94, 128 },
},
{
.mbus_code = MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE,
.colorspace = V4L2_COLORSPACE_SRGB,
.regs = ov7670_fmt_rgb444,
.cmatrix = { 179, -179, 0, -61, -176, 228 },
},
{
.mbus_code = MEDIA_BUS_FMT_RGB565_2X8_LE,
.colorspace = V4L2_COLORSPACE_SRGB,
.regs = ov7670_fmt_rgb565,
.cmatrix = { 179, -179, 0, -61, -176, 228 },
},
{
.mbus_code = MEDIA_BUS_FMT_SBGGR8_1X8,
.colorspace = V4L2_COLORSPACE_SRGB,
.regs = ov7670_fmt_raw,
.cmatrix = { 0, 0, 0, 0, 0, 0 },
},
};
#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 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 = 168, /* Empirically determined */
.hstop = 24,
.vstart = 12,
.vstop = 492,
.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,
}
};
static struct ov7670_win_size ov7675_win_sizes[] = {
/*
* Currently, only VGA is supported. Theoretically it could be possible
* to support CIF, QVGA and QCIF too. Taking values for ov7670 as a
* base and tweak them empirically could be required.
*/
{
.width = VGA_WIDTH,
.height = VGA_HEIGHT,
.com7_bit = COM7_FMT_VGA,
.hstart = 158, /* These values from */
.hstop = 14, /* Omnivision */
.vstart = 14, /* Empirically determined */
.vstop = 494,
.regs = NULL,
}
};
static void ov7675_get_framerate(struct v4l2_subdev *sd,
struct v4l2_fract *tpf)
{
struct ov7670_info *info = to_state(sd);
u32 clkrc = info->clkrc;
int pll_factor;
if (info->pll_bypass)
pll_factor = 1;
else
pll_factor = PLL_FACTOR;
clkrc++;
if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
clkrc = (clkrc >> 1);
tpf->numerator = 1;
tpf->denominator = (5 * pll_factor * info->clock_speed) /
(4 * clkrc);
}
static int ov7675_apply_framerate(struct v4l2_subdev *sd)
{
struct ov7670_info *info = to_state(sd);
int ret;
ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
if (ret < 0)
return ret;
return ov7670_write(sd, REG_DBLV,
info->pll_bypass ? DBLV_BYPASS : DBLV_X4);
}
static int ov7675_set_framerate(struct v4l2_subdev *sd,
struct v4l2_fract *tpf)
{
struct ov7670_info *info = to_state(sd);
u32 clkrc;
int pll_factor;
/*
* The formula is fps = 5/4*pixclk for YUV/RGB and
* fps = 5/2*pixclk for RAW.
*
* pixclk = clock_speed / (clkrc + 1) * PLLfactor
*
*/
if (tpf->numerator == 0 || tpf->denominator == 0) {
clkrc = 0;
} else {
pll_factor = info->pll_bypass ? 1 : PLL_FACTOR;
clkrc = (5 * pll_factor * info->clock_speed * tpf->numerator) /
(4 * tpf->denominator);
if (info->fmt->mbus_code == MEDIA_BUS_FMT_SBGGR8_1X8)
clkrc = (clkrc << 1);
clkrc--;
}
/*
* The datasheet claims that clkrc = 0 will divide the input clock by 1
* but we've checked with an oscilloscope that it divides by 2 instead.
* So, if clkrc = 0 just bypass the divider.
*/
if (clkrc <= 0)
clkrc = CLK_EXT;
else if (clkrc > CLK_SCALE)
clkrc = CLK_SCALE;
info->clkrc = clkrc;
/* Recalculate frame rate */
ov7675_get_framerate(sd, tpf);
/*
* If the device is not powered up by the host driver do
* not apply any changes to H/W at this time. Instead
* the framerate will be restored right after power-up.
*/
if (info->on)
return ov7675_apply_framerate(sd);
return 0;
}
static void ov7670_get_framerate_legacy(struct v4l2_subdev *sd,
struct v4l2_fract *tpf)
{
struct ov7670_info *info = to_state(sd);
tpf->numerator = 1;
tpf->denominator = info->clock_speed;
if ((info->clkrc & CLK_EXT) == 0 && (info->clkrc & CLK_SCALE) > 1)
tpf->denominator /= (info->clkrc & CLK_SCALE);
}
static int ov7670_set_framerate_legacy(struct v4l2_subdev *sd,
struct v4l2_fract *tpf)
{
struct ov7670_info *info = to_state(sd);
int div;
if (tpf->numerator == 0 || tpf->denominator == 0)
div = 1; /* Reset to full rate */
else
div = (tpf->numerator * info->clock_speed) / tpf->denominator;
if (div == 0)
div = 1;
else if (div > CLK_SCALE)
div = CLK_SCALE;
info->clkrc = (info->clkrc & 0x80) | div;
tpf->numerator = 1;
tpf->denominator = info->clock_speed / div;
/*
* If the device is not powered up by the host driver do
* not apply any changes to H/W at this time. Instead
* the framerate will be restored right after power-up.
*/
if (info->on)
return ov7670_write(sd, REG_CLKRC, info->clkrc);
return 0;
}
/*
* Store a set of start/stop values into the camera.
*/
static int ov7670_set_hw(struct v4l2_subdev *sd, 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(sd, REG_HSTART, (hstart >> 3) & 0xff);
if (ret)
return ret;
ret = ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff);
if (ret)
return ret;
ret = ov7670_read(sd, REG_HREF, &v);
if (ret)
return ret;
v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7);
msleep(10);
ret = ov7670_write(sd, REG_HREF, v);
if (ret)
return ret;
/* Vertical: similar arrangement, but only 10 bits. */
ret = ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff);
if (ret)
return ret;
ret = ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff);
if (ret)
return ret;
ret = ov7670_read(sd, REG_VREF, &v);
if (ret)
return ret;
v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3);
msleep(10);
return ov7670_write(sd, REG_VREF, v);
}
static int ov7670_enum_mbus_code(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_mbus_code_enum *code)
{
if (code->pad || code->index >= N_OV7670_FMTS)
return -EINVAL;
code->code = ov7670_formats[code->index].mbus_code;
return 0;
}
static int ov7670_try_fmt_internal(struct v4l2_subdev *sd,
struct v4l2_mbus_framefmt *fmt,
struct ov7670_format_struct **ret_fmt,
struct ov7670_win_size **ret_wsize)
{
int index, i;
struct ov7670_win_size *wsize;
struct ov7670_info *info = to_state(sd);
unsigned int n_win_sizes = info->devtype->n_win_sizes;
unsigned int win_sizes_limit = n_win_sizes;
for (index = 0; index < N_OV7670_FMTS; index++)
if (ov7670_formats[index].mbus_code == fmt->code)
break;
if (index >= N_OV7670_FMTS) {
/* default to first format */
index = 0;
fmt->code = ov7670_formats[0].mbus_code;
}
if (ret_fmt != NULL)
*ret_fmt = ov7670_formats + index;
/*
* Fields: the OV devices claim to be progressive.
*/
fmt->field = V4L2_FIELD_NONE;
/*
* Don't consider values that don't match min_height and min_width
* constraints.
*/
if (info->min_width || info->min_height)
for (i = 0; i < n_win_sizes; i++) {
wsize = info->devtype->win_sizes + i;
if (wsize->width < info->min_width ||
wsize->height < info->min_height) {
win_sizes_limit = i;
break;
}
}
/*
* Round requested image size down to the nearest
* we support, but not below the smallest.
*/
for (wsize = info->devtype->win_sizes;
wsize < info->devtype->win_sizes + win_sizes_limit; wsize++)
if (fmt->width >= wsize->width && fmt->height >= wsize->height)
break;
if (wsize >= info->devtype->win_sizes + win_sizes_limit)
wsize--; /* Take the smallest one */
if (ret_wsize != NULL)
*ret_wsize = wsize;
/*
* Note the size we'll actually handle.
*/
fmt->width = wsize->width;
fmt->height = wsize->height;
fmt->colorspace = ov7670_formats[index].colorspace;
info->format = *fmt;
return 0;
}
static int ov7670_apply_fmt(struct v4l2_subdev *sd)
{
struct ov7670_info *info = to_state(sd);
struct ov7670_win_size *wsize = info->wsize;
unsigned char com7, com10 = 0;
int 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 = info->fmt->regs[0].value;
com7 |= wsize->com7_bit;
ret = ov7670_write(sd, REG_COM7, com7);
if (ret)
return ret;
/*
* Configure the media bus through COM10 register
*/
if (info->mbus_config & V4L2_MBUS_VSYNC_ACTIVE_LOW)
com10 |= COM10_VS_NEG;
if (info->mbus_config & V4L2_MBUS_HSYNC_ACTIVE_LOW)
com10 |= COM10_HREF_REV;
if (info->pclk_hb_disable)
com10 |= COM10_PCLK_HB;
ret = ov7670_write(sd, REG_COM10, com10);
if (ret)
return ret;
/*
* Now write the rest of the array. Also store start/stops
*/
ret = ov7670_write_array(sd, info->fmt->regs + 1);
if (ret)
return ret;
ret = ov7670_set_hw(sd, wsize->hstart, wsize->hstop, wsize->vstart,
wsize->vstop);
if (ret)
return ret;
if (wsize->regs) {
ret = ov7670_write_array(sd, wsize->regs);
if (ret)
return ret;
}
/*
* If we're running RGB565, we must rewrite clkrc after setting
* the other parameters or the image looks poor. If we're *not*
* doing RGB565, we must not rewrite clkrc or the image looks
* *really* poor.
*
* (Update) Now that we retain clkrc state, we should be able
* to write it unconditionally, and that will make the frame
* rate persistent too.
*/
ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
if (ret)
return ret;
return 0;
}
/*
* Set a format.
*/
static int ov7670_set_fmt(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_format *format)
{
struct ov7670_info *info = to_state(sd);
struct v4l2_mbus_framefmt *mbus_fmt;
int ret;
if (format->pad)
return -EINVAL;
if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
ret = ov7670_try_fmt_internal(sd, &format->format, NULL, NULL);
if (ret)
return ret;
mbus_fmt = v4l2_subdev_state_get_format(sd_state, format->pad);
*mbus_fmt = format->format;
return 0;
}
ret = ov7670_try_fmt_internal(sd, &format->format, &info->fmt, &info->wsize);
if (ret)
return ret;
/*
* If the device is not powered up by the host driver do
* not apply any changes to H/W at this time. Instead
* the frame format will be restored right after power-up.
*/
if (info->on)
return ov7670_apply_fmt(sd);
return 0;
}
static int ov7670_get_fmt(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_format *format)
{
struct ov7670_info *info = to_state(sd);
struct v4l2_mbus_framefmt *mbus_fmt;
if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
mbus_fmt = v4l2_subdev_state_get_format(sd_state, 0);
format->format = *mbus_fmt;
return 0;
} else {
format->format = info->format;
}
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_get_frame_interval(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_frame_interval *ival)
{
struct ov7670_info *info = to_state(sd);
/*
* FIXME: Implement support for V4L2_SUBDEV_FORMAT_TRY, using the V4L2
* subdev active state API.
*/
if (ival->which != V4L2_SUBDEV_FORMAT_ACTIVE)
return -EINVAL;
info->devtype->get_framerate(sd, &ival->interval);
return 0;
}
static int ov7670_set_frame_interval(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_frame_interval *ival)
{
struct v4l2_fract *tpf = &ival->interval;
struct ov7670_info *info = to_state(sd);
/*
* FIXME: Implement support for V4L2_SUBDEV_FORMAT_TRY, using the V4L2
* subdev active state API.
*/
if (ival->which != V4L2_SUBDEV_FORMAT_ACTIVE)
return -EINVAL;
return info->devtype->set_framerate(sd, tpf);
}
/*
* Frame intervals. Since frame rates are controlled with the clock
* divider, we can only do 30/n for integer n values. So no continuous
* or stepwise options. Here we just pick a handful of logical values.
*/
static int ov7670_frame_rates[] = { 30, 15, 10, 5, 1 };
static int ov7670_enum_frame_interval(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_frame_interval_enum *fie)
{
struct ov7670_info *info = to_state(sd);
unsigned int n_win_sizes = info->devtype->n_win_sizes;
int i;
if (fie->pad)
return -EINVAL;
if (fie->index >= ARRAY_SIZE(ov7670_frame_rates))
return -EINVAL;
/*
* Check if the width/height is valid.
*
* If a minimum width/height was requested, filter out the capture
* windows that fall outside that.
*/
for (i = 0; i < n_win_sizes; i++) {
struct ov7670_win_size *win = &info->devtype->win_sizes[i];
if (info->min_width && win->width < info->min_width)
continue;
if (info->min_height && win->height < info->min_height)
continue;
if (fie->width == win->width && fie->height == win->height)
break;
}
if (i == n_win_sizes)
return -EINVAL;
fie->interval.numerator = 1;
fie->interval.denominator = ov7670_frame_rates[fie->index];
return 0;
}
/*
* Frame size enumeration
*/
static int ov7670_enum_frame_size(struct v4l2_subdev *sd,
struct v4l2_subdev_state *sd_state,
struct v4l2_subdev_frame_size_enum *fse)
{
struct ov7670_info *info = to_state(sd);
int i;
int num_valid = -1;
__u32 index = fse->index;
unsigned int n_win_sizes = info->devtype->n_win_sizes;
if (fse->pad)
return -EINVAL;
/*
* If a minimum width/height was requested, filter out the capture
* windows that fall outside that.
*/
for (i = 0; i < n_win_sizes; i++) {
struct ov7670_win_size *win = &info->devtype->win_sizes[i];
if (info->min_width && win->width < info->min_width)
continue;
if (info->min_height && win->height < info->min_height)
continue;
if (index == ++num_valid) {
fse->min_width = fse->max_width = win->width;
fse->min_height = fse->max_height = win->height;
return 0;
}
}
return -EINVAL;
}
/*
* Code for dealing with controls.
*/
static int ov7670_store_cmatrix(struct v4l2_subdev *sd,
int matrix[CMATRIX_LEN])
{
int i, ret;
unsigned char signbits = 0;
/*
* Weird crap seems to exist in the upper part of
* the sign bits register, so let's preserve it.
*/
ret = ov7670_read(sd, 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(sd, REG_CMATRIX_BASE + i, raw);
if (ret)
return ret;
}
return ov7670_write(sd, REG_CMATRIX_SIGN, signbits);
}
/*
* 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 sat, int hue)
{
int i;
/*
* Apply the current saturation setting first.
*/
for (i = 0; i < CMATRIX_LEN; i++)
matrix[i] = (info->fmt->cmatrix[i] * sat) >> 7;
/*
* Then, if need be, rotate the hue value.
*/
if (hue != 0) {
int sinth, costh, tmpmatrix[CMATRIX_LEN];
memcpy(tmpmatrix, matrix, CMATRIX_LEN*sizeof(int));
sinth = ov7670_sine(hue);
costh = ov7670_cosine(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_s_sat_hue(struct v4l2_subdev *sd, int sat, int hue)
{
struct ov7670_info *info = to_state(sd);
int matrix[CMATRIX_LEN];
ov7670_calc_cmatrix(info, matrix, sat, hue);
return ov7670_store_cmatrix(sd, matrix);
}
/*
* Some weird registers seem to store values in a sign/magnitude format!
*/
static unsigned char ov7670_abs_to_sm(unsigned char v)
{
if (v > 127)
return v & 0x7f;
return (128 - v) | 0x80;
}
static int ov7670_s_brightness(struct v4l2_subdev *sd, int value)
{
unsigned char com8 = 0, v;
ov7670_read(sd, REG_COM8, &com8);
com8 &= ~COM8_AEC;
ov7670_write(sd, REG_COM8, com8);
v = ov7670_abs_to_sm(value);
return ov7670_write(sd, REG_BRIGHT, v);
}
static int ov7670_s_contrast(struct v4l2_subdev *sd, int value)
{
return ov7670_write(sd, REG_CONTRAS, (unsigned char) value);
}
static int ov7670_s_hflip(struct v4l2_subdev *sd, int value)
{
unsigned char v = 0;
int ret;
ret = ov7670_read(sd, REG_MVFP, &v);
if (ret)
return ret;
if (value)
v |= MVFP_MIRROR;
else
v &= ~MVFP_MIRROR;
msleep(10); /* FIXME */
return ov7670_write(sd, REG_MVFP, v);
}
static int ov7670_s_vflip(struct v4l2_subdev *sd, int value)
{
unsigned char v = 0;
int ret;
ret = ov7670_read(sd, REG_MVFP, &v);
if (ret)
return ret;
if (value)
v |= MVFP_FLIP;
else
v &= ~MVFP_FLIP;
msleep(10); /* FIXME */
return ov7670_write(sd, REG_MVFP, v);
}
/*
* GAIN is split between REG_GAIN and REG_VREF[7:6]. If one believes
* the data sheet, the VREF parts should be the most significant, but
* experience shows otherwise. There seems to be little value in
* messing with the VREF bits, so we leave them alone.
*/
static int ov7670_g_gain(struct v4l2_subdev *sd, __s32 *value)
{
int ret;
unsigned char gain;
ret = ov7670_read(sd, REG_GAIN, &gain);
if (ret)
return ret;
*value = gain;
return 0;
}
static int ov7670_s_gain(struct v4l2_subdev *sd, int value)
{
int ret;
unsigned char com8;
ret = ov7670_write(sd, REG_GAIN, value & 0xff);
if (ret)
return ret;
/* Have to turn off AGC as well */
ret = ov7670_read(sd, REG_COM8, &com8);
if (ret)
return ret;
return ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
}
/*
* Tweak autogain.
*/
static int ov7670_s_autogain(struct v4l2_subdev *sd, int value)
{
int ret;
unsigned char com8;
ret = ov7670_read(sd, REG_COM8, &com8);
if (ret == 0) {
if (value)
com8 |= COM8_AGC;
else
com8 &= ~COM8_AGC;
ret = ov7670_write(sd, REG_COM8, com8);
}
return ret;
}
static int ov7670_s_exp(struct v4l2_subdev *sd, int value)
{
int ret;
unsigned char com1, com8, aech, aechh;
ret = ov7670_read(sd, REG_COM1, &com1) +
ov7670_read(sd, REG_COM8, &com8) +
ov7670_read(sd, REG_AECHH, &aechh);
if (ret)
return ret;
com1 = (com1 & 0xfc) | (value & 0x03);
aech = (value >> 2) & 0xff;
aechh = (aechh & 0xc0) | ((value >> 10) & 0x3f);
ret = ov7670_write(sd, REG_COM1, com1) +
ov7670_write(sd, REG_AECH, aech) +
ov7670_write(sd, REG_AECHH, aechh);
/* Have to turn off AEC as well */
if (ret == 0)
ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AEC);
return ret;
}
/*
* Tweak autoexposure.
*/
static int ov7670_s_autoexp(struct v4l2_subdev *sd,
enum v4l2_exposure_auto_type value)
{
int ret;
unsigned char com8;
ret = ov7670_read(sd, REG_COM8, &com8);
if (ret == 0) {
if (value == V4L2_EXPOSURE_AUTO)
com8 |= COM8_AEC;
else
com8 &= ~COM8_AEC;
ret = ov7670_write(sd, REG_COM8, com8);
}
return ret;
}
static const char * const ov7670_test_pattern_menu[] = {
"No test output",
"Shifting \"1\"",
"8-bar color bar",
"Fade to gray color bar",
};
static int ov7670_s_test_pattern(struct v4l2_subdev *sd, int value)
{
int ret;
ret = ov7670_update_bits(sd, REG_SCALING_XSC, TEST_PATTTERN_0,
value & BIT(0) ? TEST_PATTTERN_0 : 0);
if (ret)
return ret;
return ov7670_update_bits(sd, REG_SCALING_YSC, TEST_PATTTERN_1,
value & BIT(1) ? TEST_PATTTERN_1 : 0);
}
static int ov7670_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
{
struct v4l2_subdev *sd = to_sd(ctrl);
struct ov7670_info *info = to_state(sd);
switch (ctrl->id) {
case V4L2_CID_AUTOGAIN:
return ov7670_g_gain(sd, &info->gain->val);
}
return -EINVAL;
}
static int ov7670_s_ctrl(struct v4l2_ctrl *ctrl)
{
struct v4l2_subdev *sd = to_sd(ctrl);
struct ov7670_info *info = to_state(sd);
switch (ctrl->id) {
case V4L2_CID_BRIGHTNESS:
return ov7670_s_brightness(sd, ctrl->val);
case V4L2_CID_CONTRAST:
return ov7670_s_contrast(sd, ctrl->val);
case V4L2_CID_SATURATION:
return ov7670_s_sat_hue(sd,
info->saturation->val, info->hue->val);
case V4L2_CID_VFLIP:
return ov7670_s_vflip(sd, ctrl->val);
case V4L2_CID_HFLIP:
return ov7670_s_hflip(sd, ctrl->val);
case V4L2_CID_AUTOGAIN:
/* Only set manual gain if auto gain is not explicitly
turned on. */
if (!ctrl->val) {
/* ov7670_s_gain turns off auto gain */
return ov7670_s_gain(sd, info->gain->val);
}
return ov7670_s_autogain(sd, ctrl->val);
case V4L2_CID_EXPOSURE_AUTO:
/* Only set manual exposure if auto exposure is not explicitly
turned on. */
if (ctrl->val == V4L2_EXPOSURE_MANUAL) {
/* ov7670_s_exp turns off auto exposure */
return ov7670_s_exp(sd, info->exposure->val);
}
return ov7670_s_autoexp(sd, ctrl->val);
case V4L2_CID_TEST_PATTERN:
return ov7670_s_test_pattern(sd, ctrl->val);
}
return -EINVAL;
}
static const struct v4l2_ctrl_ops ov7670_ctrl_ops = {
.s_ctrl = ov7670_s_ctrl,
.g_volatile_ctrl = ov7670_g_volatile_ctrl,
};
#ifdef CONFIG_VIDEO_ADV_DEBUG
static int ov7670_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
{
unsigned char val = 0;
int ret;
ret = ov7670_read(sd, reg->reg & 0xff, &val);
reg->val = val;
reg->size = 1;
return ret;
}
static int ov7670_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
{
ov7670_write(sd, reg->reg & 0xff, reg->val & 0xff);
return 0;
}
#endif
static void ov7670_power_on(struct v4l2_subdev *sd)
{
struct ov7670_info *info = to_state(sd);
if (info->on)
return;
clk_prepare_enable(info->clk);
if (info->pwdn_gpio)
gpiod_set_value(info->pwdn_gpio, 0);
if (info->resetb_gpio) {
gpiod_set_value(info->resetb_gpio, 1);
usleep_range(500, 1000);
gpiod_set_value(info->resetb_gpio, 0);
}
if (info->pwdn_gpio || info->resetb_gpio || info->clk)
usleep_range(3000, 5000);
info->on = true;
}
static void ov7670_power_off(struct v4l2_subdev *sd)
{
struct ov7670_info *info = to_state(sd);
if (!info->on)
return;
clk_disable_unprepare(info->clk);
if (info->pwdn_gpio)
gpiod_set_value(info->pwdn_gpio, 1);
info->on = false;
}
static int ov7670_s_power(struct v4l2_subdev *sd, int on)
{
struct ov7670_info *info = to_state(sd);
if (info->on == on)
return 0;
if (on) {
ov7670_power_on(sd);
ov7670_init(sd, 0);
ov7670_apply_fmt(sd);
ov7675_apply_framerate(sd);
v4l2_ctrl_handler_setup(&info->hdl);
} else {
ov7670_power_off(sd);
}
return 0;
}
static void ov7670_get_default_format(struct v4l2_subdev *sd,
struct v4l2_mbus_framefmt *format)
{
struct ov7670_info *info = to_state(sd);
format->width = info->devtype->win_sizes[0].width;
format->height = info->devtype->win_sizes[0].height;
format->colorspace = info->fmt->colorspace;
format->code = info->fmt->mbus_code;
format->field = V4L2_FIELD_NONE;
}
static int ov7670_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
struct v4l2_mbus_framefmt *format =
v4l2_subdev_state_get_format(fh->state, 0);
ov7670_get_default_format(sd, format);
return 0;
}
/* ----------------------------------------------------------------------- */
static const struct v4l2_subdev_core_ops ov7670_core_ops = {
.reset = ov7670_reset,
.init = ov7670_init,
.s_power = ov7670_s_power,
.log_status = v4l2_ctrl_subdev_log_status,
.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
.unsubscribe_event = v4l2_event_subdev_unsubscribe,
#ifdef CONFIG_VIDEO_ADV_DEBUG
.g_register = ov7670_g_register,
.s_register = ov7670_s_register,
#endif
};
static const struct v4l2_subdev_pad_ops ov7670_pad_ops = {
.enum_frame_interval = ov7670_enum_frame_interval,
.enum_frame_size = ov7670_enum_frame_size,
.enum_mbus_code = ov7670_enum_mbus_code,
.get_fmt = ov7670_get_fmt,
.set_fmt = ov7670_set_fmt,
.get_frame_interval = ov7670_get_frame_interval,
.set_frame_interval = ov7670_set_frame_interval,
};
static const struct v4l2_subdev_ops ov7670_ops = {
.core = &ov7670_core_ops,
.pad = &ov7670_pad_ops,
};
static const struct v4l2_subdev_internal_ops ov7670_subdev_internal_ops = {
.open = ov7670_open,
};
/* ----------------------------------------------------------------------- */
static int ov7670_init_gpio(struct i2c_client *client, struct ov7670_info *info)
{
info->pwdn_gpio = devm_gpiod_get_optional(&client->dev, "powerdown",
GPIOD_OUT_LOW);
if (IS_ERR(info->pwdn_gpio)) {
dev_info(&client->dev, "can't get %s GPIO\n", "powerdown");
return PTR_ERR(info->pwdn_gpio);
}
info->resetb_gpio = devm_gpiod_get_optional(&client->dev, "reset",
GPIOD_OUT_LOW);
if (IS_ERR(info->resetb_gpio)) {
dev_info(&client->dev, "can't get %s GPIO\n", "reset");
return PTR_ERR(info->resetb_gpio);
}
usleep_range(3000, 5000);
return 0;
}
/*
* ov7670_parse_dt() - Parse device tree to collect mbus configuration
* properties
*/
static int ov7670_parse_dt(struct device *dev,
struct ov7670_info *info)
{
struct fwnode_handle *fwnode = dev_fwnode(dev);
struct v4l2_fwnode_endpoint bus_cfg = { .bus_type = 0 };
struct fwnode_handle *ep;
int ret;
if (!fwnode)
return -EINVAL;
info->pclk_hb_disable = false;
if (fwnode_property_present(fwnode, "ov7670,pclk-hb-disable"))
info->pclk_hb_disable = true;
ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
if (!ep)
return -EINVAL;
ret = v4l2_fwnode_endpoint_parse(ep, &bus_cfg);
fwnode_handle_put(ep);
if (ret)
return ret;
if (bus_cfg.bus_type != V4L2_MBUS_PARALLEL) {
dev_err(dev, "Unsupported media bus type\n");
return -EINVAL;
}
info->mbus_config = bus_cfg.bus.parallel.flags;
return 0;
}
static int ov7670_probe(struct i2c_client *client)
{
struct v4l2_fract tpf;
struct v4l2_subdev *sd;
struct ov7670_info *info;
int ret;
info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
if (info == NULL)
return -ENOMEM;
sd = &info->sd;
v4l2_i2c_subdev_init(sd, client, &ov7670_ops);
sd->internal_ops = &ov7670_subdev_internal_ops;
sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
info->clock_speed = 30; /* default: a guess */
if (dev_fwnode(&client->dev)) {
ret = ov7670_parse_dt(&client->dev, info);
if (ret)
return ret;
} else if (client->dev.platform_data) {
struct ov7670_config *config = client->dev.platform_data;
/*
* Must apply configuration before initializing device, because it
* selects I/O method.
*/
info->min_width = config->min_width;
info->min_height = config->min_height;
info->use_smbus = config->use_smbus;
if (config->clock_speed)
info->clock_speed = config->clock_speed;
if (config->pll_bypass)
info->pll_bypass = true;
if (config->pclk_hb_disable)
info->pclk_hb_disable = true;
}
info->clk = devm_clk_get_optional(&client->dev, "xclk");
if (IS_ERR(info->clk))
return PTR_ERR(info->clk);
ret = ov7670_init_gpio(client, info);
if (ret)
return ret;
ov7670_power_on(sd);
if (info->clk) {
info->clock_speed = clk_get_rate(info->clk) / 1000000;
if (info->clock_speed < 10 || info->clock_speed > 48) {
ret = -EINVAL;
goto power_off;
}
}
/* Make sure it's an ov7670 */
ret = ov7670_detect(sd);
if (ret) {
v4l_dbg(1, debug, client,
"chip found @ 0x%x (%s) is not an ov7670 chip.\n",
client->addr << 1, client->adapter->name);
goto power_off;
}
v4l_info(client, "chip found @ 0x%02x (%s)\n",
client->addr << 1, client->adapter->name);
info->devtype = i2c_get_match_data(client);
info->fmt = &ov7670_formats[0];
info->wsize = &info->devtype->win_sizes[0];
ov7670_get_default_format(sd, &info->format);
info->clkrc = 0;
/* Set default frame rate to 30 fps */
tpf.numerator = 1;
tpf.denominator = 30;
info->devtype->set_framerate(sd, &tpf);
v4l2_ctrl_handler_init(&info->hdl, 10);
v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_BRIGHTNESS, 0, 255, 1, 128);
v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_CONTRAST, 0, 127, 1, 64);
v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_VFLIP, 0, 1, 1, 0);
v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_HFLIP, 0, 1, 1, 0);
info->saturation = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_SATURATION, 0, 256, 1, 128);
info->hue = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_HUE, -180, 180, 5, 0);
info->gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_GAIN, 0, 255, 1, 128);
info->auto_gain = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
info->exposure = v4l2_ctrl_new_std(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_EXPOSURE, 0, 65535, 1, 500);
info->auto_exposure = v4l2_ctrl_new_std_menu(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_EXPOSURE_AUTO, V4L2_EXPOSURE_MANUAL, 0,
V4L2_EXPOSURE_AUTO);
v4l2_ctrl_new_std_menu_items(&info->hdl, &ov7670_ctrl_ops,
V4L2_CID_TEST_PATTERN,
ARRAY_SIZE(ov7670_test_pattern_menu) - 1, 0, 0,
ov7670_test_pattern_menu);
sd->ctrl_handler = &info->hdl;
if (info->hdl.error) {
ret = info->hdl.error;
goto hdl_free;
}
/*
* We have checked empirically that hw allows to read back the gain
* value chosen by auto gain but that's not the case for auto exposure.
*/
v4l2_ctrl_auto_cluster(2, &info->auto_gain, 0, true);
v4l2_ctrl_auto_cluster(2, &info->auto_exposure,
V4L2_EXPOSURE_MANUAL, false);
v4l2_ctrl_cluster(2, &info->saturation);
info->pad.flags = MEDIA_PAD_FL_SOURCE;
info->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
ret = media_entity_pads_init(&info->sd.entity, 1, &info->pad);
if (ret < 0)
goto hdl_free;
v4l2_ctrl_handler_setup(&info->hdl);
ret = v4l2_async_register_subdev(&info->sd);
if (ret < 0)
goto entity_cleanup;
ov7670_power_off(sd);
return 0;
entity_cleanup:
media_entity_cleanup(&info->sd.entity);
hdl_free:
v4l2_ctrl_handler_free(&info->hdl);
power_off:
ov7670_power_off(sd);
return ret;
}
static void ov7670_remove(struct i2c_client *client)
{
struct v4l2_subdev *sd = i2c_get_clientdata(client);
struct ov7670_info *info = to_state(sd);
v4l2_async_unregister_subdev(sd);
v4l2_ctrl_handler_free(&info->hdl);
media_entity_cleanup(&info->sd.entity);
}
static const struct ov7670_devtype ov7670_devdata = {
.win_sizes = ov7670_win_sizes,
.n_win_sizes = ARRAY_SIZE(ov7670_win_sizes),
.set_framerate = ov7670_set_framerate_legacy,
.get_framerate = ov7670_get_framerate_legacy,
};
static const struct ov7670_devtype ov7675_devdata = {
.win_sizes = ov7675_win_sizes,
.n_win_sizes = ARRAY_SIZE(ov7675_win_sizes),
.set_framerate = ov7675_set_framerate,
.get_framerate = ov7675_get_framerate,
};
static const struct i2c_device_id ov7670_id[] = {
{ "ov7670", (kernel_ulong_t)&ov7670_devdata },
{ "ov7675", (kernel_ulong_t)&ov7675_devdata },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, ov7670_id);
static const struct of_device_id ov7670_of_match[] = {
{ .compatible = "ovti,ov7670", &ov7670_devdata },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, ov7670_of_match);
static struct i2c_driver ov7670_driver = {
.driver = {
.name = "ov7670",
.of_match_table = ov7670_of_match,
},
.probe = ov7670_probe,
.remove = ov7670_remove,
.id_table = ov7670_id,
};
module_i2c_driver(ov7670_driver);
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