[libcamera-devel] [PATCH 20/25] media: ov5647: Program mode only if it has changed

[Dafna Hirschfeld]

On 23.06.20 18:55, Jacopo Mondi wrote:
> Store in the driver structure a pointer to the currently applied mode
> and program a new one at s_stream(1) time only if it has changed.

Hi,
I think this can be more readably implemented with a 'is_streaming' boolean
field.

Thanks,
Dafna

> 
> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>   drivers/media/i2c/ov5647.c | 16 +++++++++++++++-
>   1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> index 39e320f321bd8..ac114269e1c73 100644
> --- a/drivers/media/i2c/ov5647.c
> +++ b/drivers/media/i2c/ov5647.c
> @@ -96,6 +96,7 @@ struct ov5647 {
>   	bool				clock_ncont;
>   	struct v4l2_ctrl_handler	ctrls;
>   	struct ov5647_mode		*mode;
> +	struct ov5647_mode		*current_mode;
>   };
>   
>   static inline struct ov5647 *to_sensor(struct v4l2_subdev *sd)
> @@ -750,9 +751,13 @@ static int ov5647_set_virtual_channel(struct v4l2_subdev *sd, int channel)
>   static int ov5647_set_mode(struct v4l2_subdev *sd)
>   {
>   	struct i2c_client *client = v4l2_get_subdevdata(sd);
> +	struct ov5647 *sensor = to_sensor(sd);
>   	u8 resetval, rdval;
>   	int ret;
>   
> +	if (sensor->mode == sensor->current_mode)
> +		return 0;
> +
>   	ret = ov5647_read(sd, OV5647_SW_STANDBY, &rdval);
>   	if (ret < 0)
>   		return ret;
> @@ -778,6 +783,8 @@ static int ov5647_set_mode(struct v4l2_subdev *sd)
>   			return ret;
>   	}
>   
> +	sensor->current_mode = sensor->mode;
> +
>   	return 0;
>   }
>   
> @@ -816,6 +823,7 @@ static int ov5647_stream_on(struct v4l2_subdev *sd)
>   
>   static int ov5647_stream_off(struct v4l2_subdev *sd)
>   {
> +	struct ov5647 *sensor = to_sensor(sd);
>   	int ret;
>   
>   	ret = ov5647_write(sd, OV5647_REG_MIPI_CTRL00, MIPI_CTRL00_CLOCK_LANE_GATE |
> @@ -827,7 +835,13 @@ static int ov5647_stream_off(struct v4l2_subdev *sd)
>   	if (ret < 0)
>   		return ret;
>   
> -	return ov5647_write(sd, OV5640_REG_PAD_OUT, 0x01);
> +	ret = ov5647_write(sd, OV5640_REG_PAD_OUT, 0x01);
> +	if (ret < 0)
> +		return ret;
> +
> +	sensor->current_mode = NULL;
> +
> +	return 0;
>   }
>   
>   static int set_sw_standby(struct v4l2_subdev *sd, bool standby)
>