[PATCHv2 02/22] drm/bridge: tc358767: reset voltage-swing & pre-emphasis

[Laurent Pinchart]

Hi Tomi,

Thank you for the patch.

On Tue, Mar 26, 2019 at 12:31:26PM +0200, Tomi Valkeinen wrote:
> We need to reset DPCD voltage-swing & pre-emphasis before starting the
> link training, as otherwise tc358767 will use the previous values as
> minimums.
> 
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
> ---
>  drivers/gpu/drm/bridge/tc358767.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
> index 7031c4f52c57..11a50f7bb4be 100644
> --- a/drivers/gpu/drm/bridge/tc358767.c
> +++ b/drivers/gpu/drm/bridge/tc358767.c
> @@ -956,6 +956,12 @@ static int tc_main_link_setup(struct tc_data *tc)
>  	if (ret < 0)
>  		goto err_dpcd_write;
>  
> +	// Reset voltage-swing & pre-emphasis

The driver uses C-style comments, I think it would be best to stick to
them to avoid a style mismatch.

> +	tmp[0] = tmp[1] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0;

You may want to wrap the line.

> +	ret = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, tmp, 2);

What branch does this series apply to ? DP_TRAINING_LANE0_SET isn't
defined in Linus' or Dave's master branches.

> +	if (ret < 0)
> +		goto err_dpcd_write;
> +

I can't comment on this as I don't have access to the device
documentation :-(

>  	ret = tc_link_training(tc, DP_TRAINING_PATTERN_1);
>  	if (ret)
>  		goto err;

-- 
Regards,

Laurent Pinchart