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path: root/drivers/media/video/ov7670.c
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Diffstat (limited to 'drivers/media/video/ov7670.c')
-rw-r--r--drivers/media/video/ov7670.c1586
1 files changed, 1586 insertions, 0 deletions
diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c
new file mode 100644
index 00000000..e7c82b29
--- /dev/null
+++ b/drivers/media/video/ov7670.c
@@ -0,0 +1,1586 @@
+/*
+ * 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/i2c.h>
+#include <linux/delay.h>
+#include <linux/videodev2.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-chip-ident.h>
+#include <media/v4l2-mediabus.h>
+#include <media/ov7670.h>
+
+MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
+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)");
+
+/*
+ * 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
+
+/*
+ * 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 v4l2_subdev sd;
+ struct ov7670_format_struct *fmt; /* Current format */
+ unsigned char sat; /* Saturation value */
+ int hue; /* Hue value */
+ 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 */
+};
+
+static inline struct ov7670_info *to_state(struct v4l2_subdev *sd)
+{
+ return container_of(sd, struct ov7670_info, 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 */
+ { 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 }, /* CCIR601 */
+ { 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 }, /* 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);
+}
+
+/*
+ * 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 {
+ enum v4l2_mbus_pixelcode mbus_code;
+ enum v4l2_colorspace colorspace;
+ struct regval_list *regs;
+ int cmatrix[CMATRIX_LEN];
+} ov7670_formats[] = {
+ {
+ .mbus_code = V4L2_MBUS_FMT_YUYV8_2X8,
+ .colorspace = V4L2_COLORSPACE_JPEG,
+ .regs = ov7670_fmt_yuv422,
+ .cmatrix = { 128, -128, 0, -34, -94, 128 },
+ },
+ {
+ .mbus_code = V4L2_MBUS_FMT_RGB444_2X8_PADHI_LE,
+ .colorspace = V4L2_COLORSPACE_SRGB,
+ .regs = ov7670_fmt_rgb444,
+ .cmatrix = { 179, -179, 0, -61, -176, 228 },
+ },
+ {
+ .mbus_code = V4L2_MBUS_FMT_RGB565_2X8_LE,
+ .colorspace = V4L2_COLORSPACE_SRGB,
+ .regs = ov7670_fmt_rgb565,
+ .cmatrix = { 179, -179, 0, -61, -176, 228 },
+ },
+ {
+ .mbus_code = V4L2_MBUS_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 {
+ 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 = 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,
+ },
+};
+
+#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 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);
+ ret += ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff);
+ ret += ov7670_read(sd, REG_HREF, &v);
+ v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7);
+ msleep(10);
+ ret += ov7670_write(sd, REG_HREF, v);
+/*
+ * Vertical: similar arrangement, but only 10 bits.
+ */
+ ret += ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff);
+ ret += ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff);
+ ret += ov7670_read(sd, REG_VREF, &v);
+ v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3);
+ msleep(10);
+ ret += ov7670_write(sd, REG_VREF, v);
+ return ret;
+}
+
+
+static int ov7670_enum_mbus_fmt(struct v4l2_subdev *sd, unsigned index,
+ enum v4l2_mbus_pixelcode *code)
+{
+ if (index >= N_OV7670_FMTS)
+ return -EINVAL;
+
+ *code = ov7670_formats[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;
+ struct ov7670_win_size *wsize;
+
+ 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;
+ /*
+ * 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 (fmt->width >= wsize->width && fmt->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.
+ */
+ fmt->width = wsize->width;
+ fmt->height = wsize->height;
+ fmt->colorspace = ov7670_formats[index].colorspace;
+ return 0;
+}
+
+static int ov7670_try_mbus_fmt(struct v4l2_subdev *sd,
+ struct v4l2_mbus_framefmt *fmt)
+{
+ return ov7670_try_fmt_internal(sd, fmt, NULL, NULL);
+}
+
+/*
+ * Set a format.
+ */
+static int ov7670_s_mbus_fmt(struct v4l2_subdev *sd,
+ struct v4l2_mbus_framefmt *fmt)
+{
+ struct ov7670_format_struct *ovfmt;
+ struct ov7670_win_size *wsize;
+ struct ov7670_info *info = to_state(sd);
+ unsigned char com7;
+ int ret;
+
+ ret = ov7670_try_fmt_internal(sd, fmt, &ovfmt, &wsize);
+
+ if (ret)
+ return ret;
+ /*
+ * COM7 is a pain in the ass, it doesn't like to be read then
+ * quickly written afterward. But we have everything we need
+ * to set it absolutely here, as long as the format-specific
+ * register sets list it first.
+ */
+ com7 = ovfmt->regs[0].value;
+ com7 |= wsize->com7_bit;
+ ov7670_write(sd, REG_COM7, com7);
+ /*
+ * Now write the rest of the array. Also store start/stops
+ */
+ ov7670_write_array(sd, ovfmt->regs + 1);
+ ov7670_set_hw(sd, wsize->hstart, wsize->hstop, wsize->vstart,
+ wsize->vstop);
+ ret = 0;
+ if (wsize->regs)
+ ret = ov7670_write_array(sd, wsize->regs);
+ info->fmt = ovfmt;
+
+ /*
+ * 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.
+ */
+ if (ret == 0)
+ ret = ov7670_write(sd, REG_CLKRC, info->clkrc);
+ return 0;
+}
+
+/*
+ * Implement G/S_PARM. There is a "high quality" mode we could try
+ * to do someday; for now, we just do the frame rate tweak.
+ */
+static int ov7670_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
+{
+ struct v4l2_captureparm *cp = &parms->parm.capture;
+ struct ov7670_info *info = to_state(sd);
+
+ if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+ return -EINVAL;
+
+ memset(cp, 0, sizeof(struct v4l2_captureparm));
+ cp->capability = V4L2_CAP_TIMEPERFRAME;
+ cp->timeperframe.numerator = 1;
+ cp->timeperframe.denominator = info->clock_speed;
+ if ((info->clkrc & CLK_EXT) == 0 && (info->clkrc & CLK_SCALE) > 1)
+ cp->timeperframe.denominator /= (info->clkrc & CLK_SCALE);
+ return 0;
+}
+
+static int ov7670_s_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
+{
+ struct v4l2_captureparm *cp = &parms->parm.capture;
+ struct v4l2_fract *tpf = &cp->timeperframe;
+ struct ov7670_info *info = to_state(sd);
+ int div;
+
+ if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+ return -EINVAL;
+ if (cp->extendedmode != 0)
+ return -EINVAL;
+
+ 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;
+ return ov7670_write(sd, REG_CLKRC, info->clkrc);
+}
+
+
+/*
+ * 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_frameintervals(struct v4l2_subdev *sd,
+ struct v4l2_frmivalenum *interval)
+{
+ if (interval->index >= ARRAY_SIZE(ov7670_frame_rates))
+ return -EINVAL;
+ interval->type = V4L2_FRMIVAL_TYPE_DISCRETE;
+ interval->discrete.numerator = 1;
+ interval->discrete.denominator = ov7670_frame_rates[interval->index];
+ return 0;
+}
+
+/*
+ * Frame size enumeration
+ */
+static int ov7670_enum_framesizes(struct v4l2_subdev *sd,
+ struct v4l2_frmsizeenum *fsize)
+{
+ struct ov7670_info *info = to_state(sd);
+ int i;
+ int num_valid = -1;
+ __u32 index = fsize->index;
+
+ /*
+ * 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 = &ov7670_win_sizes[index];
+ if (info->min_width && win->width < info->min_width)
+ continue;
+ if (info->min_height && win->height < info->min_height)
+ continue;
+ if (index == ++num_valid) {
+ fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
+ fsize->discrete.width = win->width;
+ fsize->discrete.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);
+ }
+ ret += ov7670_write(sd, 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_s_sat(struct v4l2_subdev *sd, int value)
+{
+ struct ov7670_info *info = to_state(sd);
+ int matrix[CMATRIX_LEN];
+ int ret;
+
+ info->sat = value;
+ ov7670_calc_cmatrix(info, matrix);
+ ret = ov7670_store_cmatrix(sd, matrix);
+ return ret;
+}
+
+static int ov7670_g_sat(struct v4l2_subdev *sd, __s32 *value)
+{
+ struct ov7670_info *info = to_state(sd);
+
+ *value = info->sat;
+ return 0;
+}
+
+static int ov7670_s_hue(struct v4l2_subdev *sd, int value)
+{
+ struct ov7670_info *info = to_state(sd);
+ 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(sd, matrix);
+ return ret;
+}
+
+
+static int ov7670_g_hue(struct v4l2_subdev *sd, __s32 *value)
+{
+ struct ov7670_info *info = to_state(sd);
+
+ *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;
+ return 128 - (v & 0x7f);
+}
+
+
+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;
+ int ret;
+
+ ov7670_read(sd, REG_COM8, &com8);
+ com8 &= ~COM8_AEC;
+ ov7670_write(sd, REG_COM8, com8);
+ v = ov7670_abs_to_sm(value);
+ ret = ov7670_write(sd, REG_BRIGHT, v);
+ return ret;
+}
+
+static int ov7670_g_brightness(struct v4l2_subdev *sd, __s32 *value)
+{
+ unsigned char v = 0;
+ int ret = ov7670_read(sd, REG_BRIGHT, &v);
+
+ *value = ov7670_sm_to_abs(v);
+ return ret;
+}
+
+static int ov7670_s_contrast(struct v4l2_subdev *sd, int value)
+{
+ return ov7670_write(sd, REG_CONTRAS, (unsigned char) value);
+}
+
+static int ov7670_g_contrast(struct v4l2_subdev *sd, __s32 *value)
+{
+ unsigned char v = 0;
+ int ret = ov7670_read(sd, REG_CONTRAS, &v);
+
+ *value = v;
+ return ret;
+}
+
+static int ov7670_g_hflip(struct v4l2_subdev *sd, __s32 *value)
+{
+ int ret;
+ unsigned char v = 0;
+
+ ret = ov7670_read(sd, REG_MVFP, &v);
+ *value = (v & MVFP_MIRROR) == MVFP_MIRROR;
+ return ret;
+}
+
+
+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 (value)
+ v |= MVFP_MIRROR;
+ else
+ v &= ~MVFP_MIRROR;
+ msleep(10); /* FIXME */
+ ret += ov7670_write(sd, REG_MVFP, v);
+ return ret;
+}
+
+
+
+static int ov7670_g_vflip(struct v4l2_subdev *sd, __s32 *value)
+{
+ int ret;
+ unsigned char v = 0;
+
+ ret = ov7670_read(sd, REG_MVFP, &v);
+ *value = (v & MVFP_FLIP) == MVFP_FLIP;
+ return ret;
+}
+
+
+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 (value)
+ v |= MVFP_FLIP;
+ else
+ v &= ~MVFP_FLIP;
+ msleep(10); /* FIXME */
+ ret += ov7670_write(sd, REG_MVFP, v);
+ return ret;
+}
+
+/*
+ * 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);
+ *value = gain;
+ return ret;
+}
+
+static int ov7670_s_gain(struct v4l2_subdev *sd, int value)
+{
+ int ret;
+ unsigned char com8;
+
+ ret = ov7670_write(sd, REG_GAIN, value & 0xff);
+ /* Have to turn off AGC as well */
+ if (ret == 0) {
+ ret = ov7670_read(sd, REG_COM8, &com8);
+ ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
+ }
+ return ret;
+}
+
+/*
+ * Tweak autogain.
+ */
+static int ov7670_g_autogain(struct v4l2_subdev *sd, __s32 *value)
+{
+ int ret;
+ unsigned char com8;
+
+ ret = ov7670_read(sd, REG_COM8, &com8);
+ *value = (com8 & COM8_AGC) != 0;
+ return ret;
+}
+
+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;
+}
+
+/*
+ * Exposure is spread all over the place: top 6 bits in AECHH, middle
+ * 8 in AECH, and two stashed in COM1 just for the hell of it.
+ */
+static int ov7670_g_exp(struct v4l2_subdev *sd, __s32 *value)
+{
+ int ret;
+ unsigned char com1, aech, aechh;
+
+ ret = ov7670_read(sd, REG_COM1, &com1) +
+ ov7670_read(sd, REG_AECH, &aech) +
+ ov7670_read(sd, REG_AECHH, &aechh);
+ *value = ((aechh & 0x3f) << 10) | (aech << 2) | (com1 & 0x03);
+ 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_g_autoexp(struct v4l2_subdev *sd, __s32 *value)
+{
+ int ret;
+ unsigned char com8;
+ enum v4l2_exposure_auto_type *atype = (enum v4l2_exposure_auto_type *) value;
+
+ ret = ov7670_read(sd, REG_COM8, &com8);
+ if (com8 & COM8_AEC)
+ *atype = V4L2_EXPOSURE_AUTO;
+ else
+ *atype = V4L2_EXPOSURE_MANUAL;
+ return ret;
+}
+
+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 int ov7670_queryctrl(struct v4l2_subdev *sd,
+ struct v4l2_queryctrl *qc)
+{
+ /* Fill in min, max, step and default value for these controls. */
+ switch (qc->id) {
+ case V4L2_CID_BRIGHTNESS:
+ return v4l2_ctrl_query_fill(qc, 0, 255, 1, 128);
+ case V4L2_CID_CONTRAST:
+ return v4l2_ctrl_query_fill(qc, 0, 127, 1, 64);
+ case V4L2_CID_VFLIP:
+ case V4L2_CID_HFLIP:
+ return v4l2_ctrl_query_fill(qc, 0, 1, 1, 0);
+ case V4L2_CID_SATURATION:
+ return v4l2_ctrl_query_fill(qc, 0, 256, 1, 128);
+ case V4L2_CID_HUE:
+ return v4l2_ctrl_query_fill(qc, -180, 180, 5, 0);
+ case V4L2_CID_GAIN:
+ return v4l2_ctrl_query_fill(qc, 0, 255, 1, 128);
+ case V4L2_CID_AUTOGAIN:
+ return v4l2_ctrl_query_fill(qc, 0, 1, 1, 1);
+ case V4L2_CID_EXPOSURE:
+ return v4l2_ctrl_query_fill(qc, 0, 65535, 1, 500);
+ case V4L2_CID_EXPOSURE_AUTO:
+ return v4l2_ctrl_query_fill(qc, 0, 1, 1, 0);
+ }
+ return -EINVAL;
+}
+
+static int ov7670_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
+{
+ switch (ctrl->id) {
+ case V4L2_CID_BRIGHTNESS:
+ return ov7670_g_brightness(sd, &ctrl->value);
+ case V4L2_CID_CONTRAST:
+ return ov7670_g_contrast(sd, &ctrl->value);
+ case V4L2_CID_SATURATION:
+ return ov7670_g_sat(sd, &ctrl->value);
+ case V4L2_CID_HUE:
+ return ov7670_g_hue(sd, &ctrl->value);
+ case V4L2_CID_VFLIP:
+ return ov7670_g_vflip(sd, &ctrl->value);
+ case V4L2_CID_HFLIP:
+ return ov7670_g_hflip(sd, &ctrl->value);
+ case V4L2_CID_GAIN:
+ return ov7670_g_gain(sd, &ctrl->value);
+ case V4L2_CID_AUTOGAIN:
+ return ov7670_g_autogain(sd, &ctrl->value);
+ case V4L2_CID_EXPOSURE:
+ return ov7670_g_exp(sd, &ctrl->value);
+ case V4L2_CID_EXPOSURE_AUTO:
+ return ov7670_g_autoexp(sd, &ctrl->value);
+ }
+ return -EINVAL;
+}
+
+static int ov7670_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
+{
+ switch (ctrl->id) {
+ case V4L2_CID_BRIGHTNESS:
+ return ov7670_s_brightness(sd, ctrl->value);
+ case V4L2_CID_CONTRAST:
+ return ov7670_s_contrast(sd, ctrl->value);
+ case V4L2_CID_SATURATION:
+ return ov7670_s_sat(sd, ctrl->value);
+ case V4L2_CID_HUE:
+ return ov7670_s_hue(sd, ctrl->value);
+ case V4L2_CID_VFLIP:
+ return ov7670_s_vflip(sd, ctrl->value);
+ case V4L2_CID_HFLIP:
+ return ov7670_s_hflip(sd, ctrl->value);
+ case V4L2_CID_GAIN:
+ return ov7670_s_gain(sd, ctrl->value);
+ case V4L2_CID_AUTOGAIN:
+ return ov7670_s_autogain(sd, ctrl->value);
+ case V4L2_CID_EXPOSURE:
+ return ov7670_s_exp(sd, ctrl->value);
+ case V4L2_CID_EXPOSURE_AUTO:
+ return ov7670_s_autoexp(sd,
+ (enum v4l2_exposure_auto_type) ctrl->value);
+ }
+ return -EINVAL;
+}
+
+static int ov7670_g_chip_ident(struct v4l2_subdev *sd,
+ struct v4l2_dbg_chip_ident *chip)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(sd);
+
+ return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_OV7670, 0);
+}
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+static int ov7670_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(sd);
+ unsigned char val = 0;
+ int ret;
+
+ if (!v4l2_chip_match_i2c_client(client, &reg->match))
+ return -EINVAL;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ 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, struct v4l2_dbg_register *reg)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(sd);
+
+ if (!v4l2_chip_match_i2c_client(client, &reg->match))
+ return -EINVAL;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ ov7670_write(sd, reg->reg & 0xff, reg->val & 0xff);
+ return 0;
+}
+#endif
+
+/* ----------------------------------------------------------------------- */
+
+static const struct v4l2_subdev_core_ops ov7670_core_ops = {
+ .g_chip_ident = ov7670_g_chip_ident,
+ .g_ctrl = ov7670_g_ctrl,
+ .s_ctrl = ov7670_s_ctrl,
+ .queryctrl = ov7670_queryctrl,
+ .reset = ov7670_reset,
+ .init = ov7670_init,
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+ .g_register = ov7670_g_register,
+ .s_register = ov7670_s_register,
+#endif
+};
+
+static const struct v4l2_subdev_video_ops ov7670_video_ops = {
+ .enum_mbus_fmt = ov7670_enum_mbus_fmt,
+ .try_mbus_fmt = ov7670_try_mbus_fmt,
+ .s_mbus_fmt = ov7670_s_mbus_fmt,
+ .s_parm = ov7670_s_parm,
+ .g_parm = ov7670_g_parm,
+ .enum_frameintervals = ov7670_enum_frameintervals,
+ .enum_framesizes = ov7670_enum_framesizes,
+};
+
+static const struct v4l2_subdev_ops ov7670_ops = {
+ .core = &ov7670_core_ops,
+ .video = &ov7670_video_ops,
+};
+
+/* ----------------------------------------------------------------------- */
+
+static int ov7670_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct v4l2_subdev *sd;
+ struct ov7670_info *info;
+ int ret;
+
+ info = kzalloc(sizeof(struct ov7670_info), GFP_KERNEL);
+ if (info == NULL)
+ return -ENOMEM;
+ sd = &info->sd;
+ v4l2_i2c_subdev_init(sd, client, &ov7670_ops);
+
+ info->clock_speed = 30; /* default: a guess */
+ 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;
+ }
+
+ /* 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);
+ kfree(info);
+ return ret;
+ }
+ v4l_info(client, "chip found @ 0x%02x (%s)\n",
+ client->addr << 1, client->adapter->name);
+
+ info->fmt = &ov7670_formats[0];
+ info->sat = 128; /* Review this */
+ info->clkrc = info->clock_speed / 30;
+ return 0;
+}
+
+
+static int ov7670_remove(struct i2c_client *client)
+{
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+
+ v4l2_device_unregister_subdev(sd);
+ kfree(to_state(sd));
+ return 0;
+}
+
+static const struct i2c_device_id ov7670_id[] = {
+ { "ov7670", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ov7670_id);
+
+static struct i2c_driver ov7670_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "ov7670",
+ },
+ .probe = ov7670_probe,
+ .remove = ov7670_remove,
+ .id_table = ov7670_id,
+};
+
+module_i2c_driver(ov7670_driver);
generated by cgit (git 2.34.1) at 2024-12-20 20:44:32 +0000