[PATCH 1/4] media: mt9m111: add s_stream callback

[Marco Felsch]

Add callback to check if we are already streaming. Now other callbacks
can check the state and return -EBUSY if we already streaming.

Signed-off-by: Marco Felsch <m.fel...@pengutronix.de>
---
 drivers/media/i2c/mt9m111.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/media/i2c/mt9m111.c b/drivers/media/i2c/mt9m111.c
index efda1aa95ca0..78d08a81e0e2 100644
--- a/drivers/media/i2c/mt9m111.c
+++ b/drivers/media/i2c/mt9m111.c
@@ -217,6 +217,7 @@ struct mt9m111 {
        int power_count;
        const struct mt9m111_datafmt *fmt;
        int lastpage;   /* PageMap cache value */
+       bool is_streaming;
 #ifdef CONFIG_MEDIA_CONTROLLER
        struct media_pad pad;
 #endif
@@ -880,6 +881,14 @@ static int mt9m111_enum_mbus_code(struct v4l2_subdev *sd,
        return 0;
 }
 
+static int mt9m111_s_stream(struct v4l2_subdev *sd, int enable)
+{
+       struct mt9m111 *mt9m111 = container_of(sd, struct mt9m111, subdev);
+
+       mt9m111->is_streaming = !!enable;
+       return 0;
+}
+
 static int mt9m111_g_mbus_config(struct v4l2_subdev *sd,
                                struct v4l2_mbus_config *cfg)
 {
@@ -893,6 +902,7 @@ static int mt9m111_g_mbus_config(struct v4l2_subdev *sd,
 
 static const struct v4l2_subdev_video_ops mt9m111_subdev_video_ops = {
        .g_mbus_config  = mt9m111_g_mbus_config,
+       .s_stream       = mt9m111_s_stream,
 };
 
 static const struct v4l2_subdev_pad_ops mt9m111_subdev_pad_ops = {
-- 
2.19.0