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V4L/DVB: ov7670: Wire up V4L2_CID_GAIN and V4L2_CID_AUTOGAIN

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Allow applications to play with the gain settings.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Jonathan Corbet 2010-03-04 18:50:34 -03:00 committed by Mauro Carvalho Chehab
parent 2bf7de4888
commit 8189867124
1 changed files with 73 additions and 0 deletions
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73
drivers/media/video/ov7670.c
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@ -1131,6 +1131,67 @@ static int ov7670_s_vflip(struct v4l2_subdev *sd, int value)
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;
}
static int ov7670_queryctrl(struct v4l2_subdev *sd,
struct v4l2_queryctrl *qc)
{
@ -1147,6 +1208,10 @@ static int ov7670_queryctrl(struct v4l2_subdev *sd,
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);
}
return -EINVAL;
}
@ -1166,6 +1231,10 @@ static int ov7670_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
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);
}
return -EINVAL;
}
@ -1185,6 +1254,10 @@ static int ov7670_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
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);
}
return -EINVAL;
}