[v6] MediaTek DisplayPort: support eDP and aux-bus

[PATCH v6 03/11] drm/mediatek: dp: Change logging to dev for mtk_dp_aux_transfer()

Posted by AngeloGioacchino Del Regno 1 year, 3 months ago

Change logging from drm_{err,info}() to dev_{err,info}() in functions
mtk_dp_aux_transfer() and mtk_dp_aux_do_transfer(): this will be
essential to avoid getting NULL pointer kernel panics if any kind
of error happens during AUX transfers happening before the bridge
is attached.

This may potentially start happening in a later commit implementing
aux-bus support, as AUX transfers will be triggered from the panel
driver (for EDID) before the mtk-dp bridge gets attached, and it's
done in preparation for the same.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
---
 drivers/gpu/drm/mediatek/mtk_dp.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
index 77da0d002e9f..98f63d8230e4 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp.c
+++ b/drivers/gpu/drm/mediatek/mtk_dp.c
@@ -847,7 +847,7 @@ static int mtk_dp_aux_do_transfer(struct mtk_dp *mtk_dp, bool is_read, u8 cmd,
 		u32 phy_status = mtk_dp_read(mtk_dp, MTK_DP_AUX_P0_3628) &
 				 AUX_RX_PHY_STATE_AUX_TX_P0_MASK;
 		if (phy_status != AUX_RX_PHY_STATE_AUX_TX_P0_RX_IDLE) {
-			drm_err(mtk_dp->drm_dev,
+			dev_err(mtk_dp->dev,
 				"AUX Rx Aux hang, need SW reset\n");
 			return -EIO;
 		}
@@ -2054,7 +2054,7 @@ static ssize_t mtk_dp_aux_transfer(struct drm_dp_aux *mtk_aux,
 		is_read = true;
 		break;
 	default:
-		drm_err(mtk_aux->drm_dev, "invalid aux cmd = %d\n",
+		dev_err(mtk_dp->dev, "invalid aux cmd = %d\n",
 			msg->request);
 		ret = -EINVAL;
 		goto err;
@@ -2070,7 +2070,7 @@ static ssize_t mtk_dp_aux_transfer(struct drm_dp_aux *mtk_aux,
 					     to_access, &msg->reply);
 
 		if (ret) {
-			drm_info(mtk_dp->drm_dev,
+			dev_info(mtk_dp->dev,
 				 "Failed to do AUX transfer: %d\n", ret);
 			goto err;
 		}
-- 
2.40.1

Re: [PATCH v6 03/11] drm/mediatek: dp: Change logging to dev for mtk_dp_aux_transfer()

Posted by Alexandre Mergnat 1 year, 3 months ago

Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>

On 17/07/2023 16:14, AngeloGioacchino Del Regno wrote:
> Change logging from drm_{err,info}() to dev_{err,info}() in functions
> mtk_dp_aux_transfer() and mtk_dp_aux_do_transfer(): this will be
> essential to avoid getting NULL pointer kernel panics if any kind
> of error happens during AUX transfers happening before the bridge
> is attached.
> 
> This may potentially start happening in a later commit implementing
> aux-bus support, as AUX transfers will be triggered from the panel
> driver (for EDID) before the mtk-dp bridge gets attached, and it's
> done in preparation for the same.

-- 
Regards,
Alexandre

Re: [PATCH v6 03/11] drm/mediatek: dp: Change logging to dev for mtk_dp_aux_transfer()

Posted by CK Hu (胡俊光) 1 year, 3 months ago

Hi, Angelo:

On Mon, 2023-07-17 at 16:14 +0200, AngeloGioacchino Del Regno wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  Change logging from drm_{err,info}() to dev_{err,info}() in
> functions
> mtk_dp_aux_transfer() and mtk_dp_aux_do_transfer(): this will be
> essential to avoid getting NULL pointer kernel panics if any kind
> of error happens during AUX transfers happening before the bridge
> is attached.
> 
> This may potentially start happening in a later commit implementing
> aux-bus support, as AUX transfers will be triggered from the panel
> driver (for EDID) before the mtk-dp bridge gets attached, and it's
> done in preparation for the same.

Reviewed-by: CK Hu <ck.hu@mediatek.com>

> 
> Signed-off-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> Tested-by: Chen-Yu Tsai <wenst@chromium.org>
> ---
>  drivers/gpu/drm/mediatek/mtk_dp.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c
> b/drivers/gpu/drm/mediatek/mtk_dp.c
> index 77da0d002e9f..98f63d8230e4 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dp.c
> @@ -847,7 +847,7 @@ static int mtk_dp_aux_do_transfer(struct mtk_dp
> *mtk_dp, bool is_read, u8 cmd,
>  		u32 phy_status = mtk_dp_read(mtk_dp,
> MTK_DP_AUX_P0_3628) &
>  				 AUX_RX_PHY_STATE_AUX_TX_P0_MASK;
>  		if (phy_status != AUX_RX_PHY_STATE_AUX_TX_P0_RX_IDLE) {
> -			drm_err(mtk_dp->drm_dev,
> +			dev_err(mtk_dp->dev,
>  				"AUX Rx Aux hang, need SW reset\n");
>  			return -EIO;
>  		}
> @@ -2054,7 +2054,7 @@ static ssize_t mtk_dp_aux_transfer(struct
> drm_dp_aux *mtk_aux,
>  		is_read = true;
>  		break;
>  	default:
> -		drm_err(mtk_aux->drm_dev, "invalid aux cmd = %d\n",
> +		dev_err(mtk_dp->dev, "invalid aux cmd = %d\n",
>  			msg->request);
>  		ret = -EINVAL;
>  		goto err;
> @@ -2070,7 +2070,7 @@ static ssize_t mtk_dp_aux_transfer(struct
> drm_dp_aux *mtk_aux,
>  					     to_access, &msg->reply);
>  
>  		if (ret) {
> -			drm_info(mtk_dp->drm_dev,
> +			dev_info(mtk_dp->dev,
>  				 "Failed to do AUX transfer: %d\n",
> ret);
>  			goto err;
>  		}
> -- 
> 2.40.1