Re: [Intel-gfx] [PATCH 2/4] drm/dp: use more of the extended receiver cap

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Aug 13, 2021 at 01:43:20PM +0300, Jani Nikula wrote:
> Extend the use of extended receiver cap at 0x2200 to cover
> MAIN_LINK_CHANNEL_CODING_CAP in 0x2206, in case an implementation hides
> the DP 2.0 128b/132b channel encoding cap.
> 
> Cc: Manasi Navare <manasi.d.navare@intel.com>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> ---
>  drivers/gpu/drm/drm_dp_helper.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
> index 9b2a2961fca8..9389f92cb944 100644
> --- a/drivers/gpu/drm/drm_dp_helper.c
> +++ b/drivers/gpu/drm/drm_dp_helper.c
> @@ -608,7 +608,7 @@ static u8 drm_dp_downstream_port_count(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
>  static int drm_dp_read_extended_dpcd_caps(struct drm_dp_aux *aux,
>  					  u8 dpcd[DP_RECEIVER_CAP_SIZE])
>  {
> -	u8 dpcd_ext[6];
> +	u8 dpcd_ext[DP_MAIN_LINK_CHANNEL_CODING + 1];

Why are we even reading less of this than the normal receiver caps?

>  	int ret;
>  
>  	/*
> -- 
> 2.20.1

-- 
Ville Syrjälä
Intel