[PATCH] media: ov7670: Allow 32x maximum gain for yuv422.

[Javier Martin]

4x gain ceiling is not enough to capture a decent image in conditions
of total darkness and only a LED light source. Allow a maximum gain
of 32x instead.

This doesn't have any drawback since the image quality in 'normal'
light conditions is the same.

Signed-off-by: Javier Martin javier.mar...@vista-silicon.com
---
 drivers/media/video/ov7670.c |2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c
index 5faa3d8..2ea9c51 100644
--- a/drivers/media/video/ov7670.c
+++ b/drivers/media/video/ov7670.c
@@ -366,7 +366,7 @@ static struct regval_list ov7670_fmt_yuv422[] = {
{ REG_RGB444, 0 },  /* No RGB444 please */
{ REG_COM1, 0 },/* CCIR601 */
{ REG_COM15, COM15_R00FF },
-   { REG_COM9, 0x18 }, /* 4x gain ceiling; 0x8 is reserved bit */
+   { REG_COM9, 0x48 }, /* 32x gain ceiling; 0x8 is reserved bit */
{ 0x4f, 0x80 }, /* matrix coefficient 1 */
{ 0x50, 0x80 }, /* matrix coefficient 2 */
{ 0x51, 0}, /* vb */
-- 
1.7.9.5

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Re: [PATCH] media: ov7670: Allow 32x maximum gain for yuv422.

[Jonathan Corbet]

On Tue, 30 Oct 2012 17:04:23 +0100
Javier Martin javier.mar...@vista-silicon.com wrote:

 4x gain ceiling is not enough to capture a decent image in conditions
 of total darkness and only a LED light source. Allow a maximum gain
 of 32x instead.

The initial number surely came from OmniVision and was never really
thought about.  I can't test this at the moment, but I see no reason not
to take your word that it doesn't affect normal-light operation.

Acked-by: Jonathan Corbet cor...@lwn.net

jon
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