linux-kernel - Re: [RESEND v3] drm/bridge: analogix_dp: Reuse &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <469f900d-1352-4137-94ec-4daeb5b7a998@rock-chips.com>
Date: Sun, 28 Dec 2025 16:47:25 +0800
From: Damon Ding <damon.ding@...k-chips.com>
To: andrzej.hajda@...el.com, neil.armstrong@...aro.org, rfoss@...nel.org
Cc: Laurent.pinchart@...asonboard.com, jonas@...boo.se,
 jernej.skrabec@...il.com, maarten.lankhorst@...ux.intel.com,
 mripard@...nel.org, tzimmermann@...e.de, airlied@...il.com, simona@...ll.ch,
 dmitry.baryshkov@....qualcomm.com, dianders@...omium.org,
 m.szyprowski@...sung.com, andy.yan@...k-chips.com,
 dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Subject: Re: [RESEND v3] drm/bridge: analogix_dp: Reuse
 &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx_SET

On 11/11/2025 10:21 AM, Damon Ding wrote:
> In analogix_dp_link_start(), &link_train.training_lane[] is used to
> set phy PE/VS configurations, and buf[] is initialized with the same
> values to set DPCD DP_TRAINING_LANEx_SET.
> 
> It makes sense to reuse &link_train.training_lane[] to set DPCD
> DP_TRAINING_LANEx_SET, which can remove the redundant assignments
> and make codes more concise.
> 
> Signed-off-by: Damon Ding <damon.ding@...k-chips.com>
> Tested-by: Marek Szyprowski <m.szyprowski@...sung.com>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
> 
> ---
> 
> Changes in v2:
> - Add Tested-by tag.
> 
> Changes in v3:
> - Add Reviewed-by tag.
> - Fix the spelling error 'consice' to 'concise'.

Gentle ping.

I just added tags in v2 and v3, and I also tried resend. The patch is 
merely a pre-optimization work for the following patch series:

https://lore.kernel.org/all/20251217093321.3108939-1-damon.ding@rock-chips.com/

> ---
>   drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 8 ++------
>   1 file changed, 2 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 6ec3d811b5f0..1e834d3656c1 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -281,12 +281,8 @@ static int analogix_dp_link_start(struct analogix_dp_device *dp)
>   	if (retval < 0)
>   		return retval;
>   
> -	for (lane = 0; lane < lane_count; lane++)
> -		buf[lane] = DP_TRAIN_PRE_EMPH_LEVEL_0 |
> -			    DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
> -
> -	retval = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET, buf,
> -				   lane_count);
> +	retval = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET,
> +				   dp->link_train.training_lane, lane_count);
>   	if (retval < 0)
>   		return retval;
>