From e72cb0e79475b0d26625e802846e281a84304c07 Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Thu, 8 Jun 2017 16:59:58 -0300 Subject: [PATCH] [media] v4l: ctrls: Add a control for digital gain Add V4L2_CID_DIGITAL_GAIN to control explicitly digital gain. We already have analogue gain control which the digital gain control complements. Typically higher quality images are obtained using analogue gain only as the digital gain does not add information to the image (rather it may remove it). Signed-off-by: Sakari Ailus Acked-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/media/uapi/v4l/extended-controls.rst | 7 +++++++ drivers/media/v4l2-core/v4l2-ctrls.c | 1 + include/uapi/linux/v4l2-controls.h | 2 +- 3 files changed, 9 insertions(+), 1 deletion(-) diff --git a/Documentation/media/uapi/v4l/extended-controls.rst b/Documentation/media/uapi/v4l/extended-controls.rst index 76c5b1aeaadd..9acc9cad49e2 100644 --- a/Documentation/media/uapi/v4l/extended-controls.rst +++ b/Documentation/media/uapi/v4l/extended-controls.rst @@ -3021,6 +3021,13 @@ Image Process Control IDs The video deinterlacing mode (such as Bob, Weave, ...). The menu items are driver specific and are documented in :ref:`v4l-drivers`. +``V4L2_CID_DIGITAL_GAIN (integer)`` + Digital gain is the value by which all colour components + are multiplied by. Typically the digital gain applied is the + control value divided by e.g. 0x100, meaning that to get no + digital gain the control value needs to be 0x100. The no-gain + configuration is also typically the default. + .. _dv-controls: diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c index 5aed7bd20ad2..36eede3ff098 100644 --- a/drivers/media/v4l2-core/v4l2-ctrls.c +++ b/drivers/media/v4l2-core/v4l2-ctrls.c @@ -886,6 +886,7 @@ const char *v4l2_ctrl_get_name(u32 id) case V4L2_CID_PIXEL_RATE: return "Pixel Rate"; case V4L2_CID_TEST_PATTERN: return "Test Pattern"; case V4L2_CID_DEINTERLACING_MODE: return "Deinterlacing Mode"; + case V4L2_CID_DIGITAL_GAIN: return "Digital Gain"; /* DV controls */ /* Keep the order of the 'case's the same as in v4l2-controls.h! */ diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h index 8cadcece7a29..31bfc68f86d6 100644 --- a/include/uapi/linux/v4l2-controls.h +++ b/include/uapi/linux/v4l2-controls.h @@ -902,7 +902,7 @@ enum v4l2_jpeg_chroma_subsampling { #define V4L2_CID_PIXEL_RATE (V4L2_CID_IMAGE_PROC_CLASS_BASE + 2) #define V4L2_CID_TEST_PATTERN (V4L2_CID_IMAGE_PROC_CLASS_BASE + 3) #define V4L2_CID_DEINTERLACING_MODE (V4L2_CID_IMAGE_PROC_CLASS_BASE + 4) - +#define V4L2_CID_DIGITAL_GAIN (V4L2_CID_IMAGE_PROC_CLASS_BASE + 5) /* DV-class control IDs defined by V4L2 */ #define V4L2_CID_DV_CLASS_BASE (V4L2_CTRL_CLASS_DV | 0x900)