[PATCH] media: mtk-jpeg: Set platform driver data earlier

[PATCH] media: mtk-jpeg: Set platform driver data earlier

[Chen-Yu Tsai]

In the multi-core JPEG encoder/decoder setup, the driver for the
individual cores references the parent device's platform driver data.
However, in the parent driver, this is only set at the end of the probe
function, way later than devm_of_platform_populate(), which triggers
the probe of the cores. This causes a kernel splat in the sub-device
probe function.

Move platform_set_drvdata() to before devm_of_platform_populate() to
fix this.

Fixes: 934e8bccac95 ("mtk-jpegenc: support jpegenc multi-hardware")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---
Not sure what caused this to surface just now, given that the driver
changes were merged in v6.2-rc1, and the corresponding dts entries
in v6.3-rc1.

This fixes boot failures on MT8195. Please apply and send to Linus ASAP.

 drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 4768156181c9..6a8eea9dde67 100644
--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
@@ -1312,6 +1312,8 @@ static int mtk_jpeg_probe(struct platform_device *pdev)
 	jpeg->dev = &pdev->dev;
 	jpeg->variant = of_device_get_match_data(jpeg->dev);
 
+	platform_set_drvdata(pdev, jpeg);
+
 	ret = devm_of_platform_populate(&pdev->dev);
 	if (ret) {
 		v4l2_err(&jpeg->v4l2_dev, "Master of platform populate failed.");
@@ -1383,8 +1385,6 @@ static int mtk_jpeg_probe(struct platform_device *pdev)
 		  jpeg->variant->dev_name, jpeg->vdev->num,
 		  VIDEO_MAJOR, jpeg->vdev->minor);
 
-	platform_set_drvdata(pdev, jpeg);
-
 	pm_runtime_enable(&pdev->dev);
 
 	return 0;
-- 
2.41.0.255.g8b1d071c50-goog

Re: [PATCH] media: mtk-jpeg: Set platform driver data earlier

[AngeloGioacchino Del Regno]

Il 10/07/23 08:51, Chen-Yu Tsai ha scritto:
> In the multi-core JPEG encoder/decoder setup, the driver for the
> individual cores references the parent device's platform driver data.
> However, in the parent driver, this is only set at the end of the probe
> function, way later than devm_of_platform_populate(), which triggers
> the probe of the cores. This causes a kernel splat in the sub-device
> probe function.
> 
> Move platform_set_drvdata() to before devm_of_platform_populate() to
> fix this.
> 
> Fixes: 934e8bccac95 ("mtk-jpegenc: support jpegenc multi-hardware")
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

> ---
> Not sure what caused this to surface just now, given that the driver
> changes were merged in v6.2-rc1, and the corresponding dts entries
> in v6.3-rc1.
> 
> This fixes boot failures on MT8195. Please apply and send to Linus ASAP.
> 
>   drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
> index 4768156181c9..6a8eea9dde67 100644
> --- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
> +++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
> @@ -1312,6 +1312,8 @@ static int mtk_jpeg_probe(struct platform_device *pdev)
>   	jpeg->dev = &pdev->dev;
>   	jpeg->variant = of_device_get_match_data(jpeg->dev);
>   
> +	platform_set_drvdata(pdev, jpeg);
> +
>   	ret = devm_of_platform_populate(&pdev->dev);
>   	if (ret) {
>   		v4l2_err(&jpeg->v4l2_dev, "Master of platform populate failed.");
> @@ -1383,8 +1385,6 @@ static int mtk_jpeg_probe(struct platform_device *pdev)
>   		  jpeg->variant->dev_name, jpeg->vdev->num,
>   		  VIDEO_MAJOR, jpeg->vdev->minor);
>   
> -	platform_set_drvdata(pdev, jpeg);
> -
>   	pm_runtime_enable(&pdev->dev);
>   
>   	return 0;