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authorJavier Martin <javier.martin@vista-silicon.com>2013-01-29 07:23:42 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2013-02-08 14:30:48 -0200
commit04ee6d92047e1ac68d4eb615119343f4f0fc57db (patch)
tree4862760c13c38aa3c6dd96a4ab7a01bc9eb8e7c9
parentf6dd927f34d64014c4b196132b5cdf9f2e2a3ae5 (diff)
[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>
-rw-r--r--drivers/media/i2c/ov7670.c28
-rw-r--r--include/media/ov7670.h1
2 files changed, 27 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 */
diff --git a/include/media/ov7670.h b/include/media/ov7670.h
index b133bc123031..a68c8bb3ceba 100644
--- a/include/media/ov7670.h
+++ b/include/media/ov7670.h
@@ -15,6 +15,7 @@ struct ov7670_config {
int min_height; /* Filter out smaller sizes */
int clock_speed; /* External clock speed (MHz) */
bool use_smbus; /* Use smbus I/O instead of I2C */
+ bool pll_bypass; /* Choose whether to bypass the PLL */
};
#endif

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