Hi Lars-Peter,
See some comments below:
On 03/07/2014 05:14 PM, Lars-Peter Clausen wrote:
> The adv7180 has a low power mode in which the analog and the digital processing
> section are shut down. Implement the s_power callback to let bridge drivers put
> the part into low power mode when not needed.
>
> Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
> ---
> drivers/media/i2c/adv7180.c | 52 ++++++++++++++++++++++++++++++++++++---------
> 1 file changed, 42 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/media/i2c/adv7180.c b/drivers/media/i2c/adv7180.c
> index 623cec5..8271362 100644
> --- a/drivers/media/i2c/adv7180.c
> +++ b/drivers/media/i2c/adv7180.c
> @@ -127,6 +127,7 @@ struct adv7180_state {
> int irq;
> v4l2_std_id curr_norm;
> bool autodetect;
> + bool powered;
> u8 input;
> };
> #define to_adv7180_sd(_ctrl) (&container_of(_ctrl->handler, \
> @@ -311,6 +312,39 @@ out:
> return ret;
> }
>
> +static int adv7180_set_power(struct adv7180_state *state,
> + struct i2c_client *client, bool on)
> +{
> + u8 val;
> +
> + if (on)
> + val = ADV7180_PWR_MAN_ON;
> + else
> + val = ADV7180_PWR_MAN_OFF;
> +
> + return i2c_smbus_write_byte_data(client, ADV7180_PWR_MAN_REG, val);
> +}
> +
> +static int adv7180_s_power(struct v4l2_subdev *sd, int on)
> +{
> + struct adv7180_state *state = to_state(sd);
> + struct i2c_client *client = v4l2_get_subdevdata(sd);
> + int ret;
> +
> + ret = mutex_lock_interruptible(&state->mutex);
> + if (ret)
> + return ret;
> +
> + ret = adv7180_set_power(state, client, on);
> + if (ret)
> + goto out;
> +
> + state->powered = on;
> +out:
I would change this to:
if (!ret)
state->powered = on;
and drop the 'goto'.
> + mutex_unlock(&state->mutex);
> + return ret;
> +}
> +
> static int adv7180_s_ctrl(struct v4l2_ctrl *ctrl)
> {
> struct v4l2_subdev *sd = to_adv7180_sd(ctrl);
> @@ -441,6 +475,7 @@ static const struct v4l2_subdev_video_ops adv7180_video_ops = {
>
> static const struct v4l2_subdev_core_ops adv7180_core_ops = {
> .s_std = adv7180_s_std,
> + .s_power = adv7180_s_power,
> };
>
> static const struct v4l2_subdev_ops adv7180_ops = {
> @@ -640,13 +675,9 @@ static const struct i2c_device_id adv7180_id[] = {
> static int adv7180_suspend(struct device *dev)
> {
> struct i2c_client *client = to_i2c_client(dev);
> - int ret;
> + struct adv7180_state *state = to_state(sd);
>
> - ret = i2c_smbus_write_byte_data(client, ADV7180_PWR_MAN_REG,
> - ADV7180_PWR_MAN_OFF);
> - if (ret < 0)
> - return ret;
> - return 0;
> + return adv7180_set_power(state, client, false);
> }
>
> static int adv7180_resume(struct device *dev)
> @@ -656,10 +687,11 @@ static int adv7180_resume(struct device *dev)
> struct adv7180_state *state = to_state(sd);
> int ret;
>
> - ret = i2c_smbus_write_byte_data(client, ADV7180_PWR_MAN_REG,
> - ADV7180_PWR_MAN_ON);
> - if (ret < 0)
> - return ret;
> + if (state->powered) {
> + ret = adv7180_set_power(state, client, true);
> + if (ret)
> + return ret;
> + }
> ret = init_device(client, state);
> if (ret < 0)
> return ret;
>
What is the initial state of the driver when loaded? Shouldn't probe() set the
'powered' variable to true initially?
Regards,
Hans
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
