media: adv7180: add g_skip_frames support

The adv7180 produces 1 to 2 frames of garbage before proper sync is
established. This allows V4L2 drivers and apps to skip those.

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/media/i2c/adv7180.c b/drivers/media/i2c/adv7180.c
index 99697baad2ea09d27f9b497def2d2226bfa2fb34..6f3dc8862622d72cf9a49258008336a76846fab3 100644 (file)
--- a/drivers/media/i2c/adv7180.c
+++ b/drivers/media/i2c/adv7180.c
@@ -180,6 +180,9 @@
 
 #define V4L2_CID_ADV_FAST_SWITCH       (V4L2_CID_USER_ADV7180_BASE + 0x00)
 
+/* Initial number of frames to skip to avoid possible garbage */
+#define ADV7180_NUM_OF_SKIP_FRAMES       2
+
 struct adv7180_state;
 
 #define ADV7180_FLAG_RESET_POWERED     BIT(0)
@@ -769,6 +772,13 @@ static int adv7180_g_mbus_config(struct v4l2_subdev *sd,
        return 0;
 }
 
+static int adv7180_get_skip_frames(struct v4l2_subdev *sd, u32 *frames)
+{
+       *frames = ADV7180_NUM_OF_SKIP_FRAMES;
+
+       return 0;
+}
+
 static int adv7180_g_pixelaspect(struct v4l2_subdev *sd, struct v4l2_fract *aspect)
 {
        struct adv7180_state *state = to_state(sd);
@@ -849,10 +859,15 @@ static const struct v4l2_subdev_pad_ops adv7180_pad_ops = {
        .get_fmt = adv7180_get_pad_format,
 };
 
+static const struct v4l2_subdev_sensor_ops adv7180_sensor_ops = {
+       .g_skip_frames = adv7180_get_skip_frames,
+};
+
 static const struct v4l2_subdev_ops adv7180_ops = {
        .core = &adv7180_core_ops,
        .video = &adv7180_video_ops,
        .pad = &adv7180_pad_ops,
+       .sensor = &adv7180_sensor_ops,
 };
 
 static irqreturn_t adv7180_irq(int irq, void *devid)