diff options
| author | Javier Martin <javier.martin@vista-silicon.com> | 2013-01-29 11:23:42 +0100 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2013-02-08 17:30:48 +0100 |
| commit | 04ee6d92047e1ac68d4eb615119343f4f0fc57db (patch) | |
| tree | 4862760c13c38aa3c6dd96a4ab7a01bc9eb8e7c9 /drivers/media | |
| parent | [media] media: ov7670: calculate framerate properly for ov7675 (diff) | |
| download | linux-04ee6d92047e1ac68d4eb615119343f4f0fc57db.tar.xz linux-04ee6d92047e1ac68d4eb615119343f4f0fc57db.zip | |
[media] media: ov7670: add possibility to bypass pll for ov7675
For a frame rate of 30 fps a pixclk of 24MHz is needed. For those
cases where the ov7670 has a clean 24MHz input (xvclk) the PLL
can be bypassed.
This will result in a value of clkrc of 1, which means that in practice
pixclk = xvclk (input clock)
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Javier Martin <javier.martin@vista-silicon.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/i2c/ov7670.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c index dea2917a2b12..3e503396aaa4 100644 --- a/drivers/media/i2c/ov7670.c +++ b/drivers/media/i2c/ov7670.c @@ -230,6 +230,7 @@ struct ov7670_info { 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; const struct ov7670_devtype *devtype; /* Device specifics */ }; @@ -755,7 +756,12 @@ static void ov7675_get_framerate(struct v4l2_subdev *sd, { struct ov7670_info *info = to_state(sd); u32 clkrc = info->clkrc; - u32 pll_factor = PLL_FACTOR; + int pll_factor; + + if (info->pll_bypass) + pll_factor = 1; + else + pll_factor = PLL_FACTOR; clkrc++; if (info->fmt->mbus_code == V4L2_MBUS_FMT_SBGGR8_1X8) @@ -771,7 +777,7 @@ static int ov7675_set_framerate(struct v4l2_subdev *sd, { struct ov7670_info *info = to_state(sd); u32 clkrc; - u32 pll_factor = PLL_FACTOR; + int pll_factor; int ret; /* @@ -781,6 +787,16 @@ static int ov7675_set_framerate(struct v4l2_subdev *sd, * pixclk = clock_speed / (clkrc + 1) * PLLfactor * */ + if (info->pll_bypass) { + pll_factor = 1; + ret = ov7670_write(sd, REG_DBLV, DBLV_BYPASS); + } else { + pll_factor = PLL_FACTOR; + ret = ov7670_write(sd, REG_DBLV, DBLV_X4); + } + if (ret < 0) + return ret; + if (tpf->numerator == 0 || tpf->denominator == 0) { clkrc = 0; } else { @@ -808,6 +824,7 @@ static int ov7675_set_framerate(struct v4l2_subdev *sd, ret = ov7670_write(sd, REG_CLKRC, info->clkrc); if (ret < 0) return ret; + return ov7670_write(sd, REG_DBLV, DBLV_X4); } @@ -1688,6 +1705,13 @@ static int ov7670_probe(struct i2c_client *client, if (config->clock_speed) info->clock_speed = config->clock_speed; + + /* + * It should be allowed for ov7670 too when it is migrated to + * the new frame rate formula. + */ + if (config->pll_bypass && id->driver_data != MODEL_OV7670) + info->pll_bypass = true; } /* Make sure it's an ov7670 */ |