[RESEND v3] drm/bridge: analogix_dp: Reuse &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx_SET

[RESEND v3] drm/bridge: analogix_dp: Reuse &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx_SET

[Damon Ding]

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@rock-chips.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

---

Changes in v2:
- Add Tested-by tag.

Changes in v3:
- Add Reviewed-by tag.
- Fix the spelling error 'consice' to 'concise'.
---
 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;
 
-- 
2.34.1

Re: [RESEND v3] drm/bridge: analogix_dp: Reuse &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx_SET

[Damon Ding]

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@rock-chips.com>
> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.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;
>   

Re: [RESEND v3] drm/bridge: analogix_dp: Reuse &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx_SET

[Luca Ceresoli]

On Tue Nov 11, 2025 at 3:21 AM CET, 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@rock-chips.com>
> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [RESEND v3] drm/bridge: analogix_dp: Reuse &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx_SET

[Luca Ceresoli]

On Tue, 11 Nov 2025 10:21:03 +0800, 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.
> 
> [...]

Applied, thanks!

[1/1] drm/bridge: analogix_dp: Reuse &link_train.training_lane[] to set DPCD DP_TRAINING_LANEx_SET
      commit: 05d09e7f28c8f6e39c54d79fd96643f6faf5dbee

Best regards,
-- 
Luca Ceresoli <luca.ceresoli@bootlin.com>