diff options
Diffstat (limited to 'drivers/media/i2c/ov7670.c')
| -rw-r--r-- | drivers/media/i2c/ov7670.c | 136 |
1 files changed, 118 insertions, 18 deletions
diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c index 88e6473..dea2917 100644 --- a/drivers/media/i2c/ov7670.c +++ b/drivers/media/i2c/ov7670.c @@ -47,6 +47,8 @@ MODULE_PARM_DESC(debug, "Debug level (0-1)"); */ #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 */ @@ -164,6 +166,12 @@ MODULE_PARM_DESC(debug, "Debug level (0-1)"); #define REG_GFIX 0x69 /* Fix gain control */ +#define REG_DBLV 0x6b /* PLL control an debugging */ +#define DBLV_BYPASS 0x00 /* Bypass PLL */ +#define DBLV_X4 0x01 /* clock x4 */ +#define DBLV_X6 0x10 /* clock x6 */ +#define DBLV_X8 0x11 /* clock x8 */ + #define REG_REG76 0x76 /* OV's name */ #define R76_BLKPCOR 0x80 /* Black pixel correction enable */ #define R76_WHTPCOR 0x40 /* White pixel correction enable */ @@ -203,6 +211,9 @@ 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 *); }; /* @@ -739,6 +750,98 @@ static struct ov7670_win_size ov7675_win_sizes[] = { } }; +static void ov7675_get_framerate(struct v4l2_subdev *sd, + struct v4l2_fract *tpf) +{ + struct ov7670_info *info = to_state(sd); + u32 clkrc = info->clkrc; + u32 pll_factor = PLL_FACTOR; + + clkrc++; + if (info->fmt->mbus_code == V4L2_MBUS_FMT_SBGGR8_1X8) + clkrc = (clkrc >> 1); + + tpf->numerator = 1; + tpf->denominator = (5 * pll_factor * info->clock_speed) / + (4 * clkrc); +} + +static int ov7675_set_framerate(struct v4l2_subdev *sd, + struct v4l2_fract *tpf) +{ + struct ov7670_info *info = to_state(sd); + u32 clkrc; + u32 pll_factor = PLL_FACTOR; + int ret; + + /* + * 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 { + clkrc = (5 * pll_factor * info->clock_speed * tpf->numerator) / + (4 * tpf->denominator); + if (info->fmt->mbus_code == V4L2_MBUS_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); + + ret = ov7670_write(sd, REG_CLKRC, info->clkrc); + if (ret < 0) + return ret; + return ov7670_write(sd, REG_DBLV, DBLV_X4); +} + +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; + return ov7670_write(sd, REG_CLKRC, info->clkrc); +} + /* * Store a set of start/stop values into the camera. */ @@ -913,10 +1016,8 @@ static int ov7670_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms) 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); + info->devtype->get_framerate(sd, &cp->timeperframe); + return 0; } @@ -925,25 +1026,13 @@ 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); + return info->devtype->set_framerate(sd, tpf); } @@ -1560,16 +1649,21 @@ static const struct ov7670_devtype ov7670_devdata[] = { [MODEL_OV7670] = { .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, }, [MODEL_OV7675] = { .win_sizes = ov7675_win_sizes, .n_win_sizes = ARRAY_SIZE(ov7675_win_sizes), + .set_framerate = ov7675_set_framerate, + .get_framerate = ov7675_get_framerate, }, }; static int ov7670_probe(struct i2c_client *client, const struct i2c_device_id *id) { + struct v4l2_fract tpf; struct v4l2_subdev *sd; struct ov7670_info *info; int ret; @@ -1611,7 +1705,13 @@ static int ov7670_probe(struct i2c_client *client, info->devtype = &ov7670_devdata[id->driver_data]; info->fmt = &ov7670_formats[0]; info->sat = 128; /* Review this */ - info->clkrc = info->clock_speed / 30; + info->clkrc = 0; + + /* Set default frame rate to 30 fps */ + tpf.numerator = 1; + tpf.denominator = 30; + info->devtype->set_framerate(sd, &tpf); + return 0; } |
