On Thu, Apr 3, 2025 at 7:09 PM AngeloGioacchino Del Regno
<angelogioacchino.delre...@collabora.com> wrote:
>
> During probe, this driver is registering two platform devices: one
> for the HDMI Codec driver and one for the DisplayPort PHY driver.
>
> In the probe function, none of the error cases are unregistering
> any of the two platform devices and this may cause registration
> of multiple instances of those in case this driver returns one or
> more probe deferral(s) in the "wrong" spots.
>
> In order to fix this, add devm actions to unregister those and
> remove the manual calls to platform_device_unregister in the
> mtk_dp_remove() function, as those would otherwise be redundant.
>
> Fixes: e71a8ebbe086 ("drm/mediatek: dp: Audio support for MT8195")
> Fixes: caf2ae486742 ("drm/mediatek: dp: Add support for embedded DisplayPort
> aux-bus")
> Signed-off-by: AngeloGioacchino Del Regno
> <angelogioacchino.delre...@collabora.com>
> ---
> drivers/gpu/drm/mediatek/mtk_dp.c | 30 ++++++++++++++++++++++++++----
> 1 file changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c
> b/drivers/gpu/drm/mediatek/mtk_dp.c
> index 3d4648d2e15f..3eb685a46d99 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dp.c
> @@ -2648,6 +2648,13 @@ static const struct hdmi_codec_ops
> mtk_dp_audio_codec_ops = {
> .hook_plugged_cb = mtk_dp_audio_hook_plugged_cb,
> };
>
> +static void mtk_dp_unregister_pdevs(void *data)
> +{
> + struct platform_device *ext_pdev = data;
> +
> + platform_device_unregister(ext_pdev);
> +}
> +
> static int mtk_dp_register_audio_driver(struct device *dev)
> {
> struct mtk_dp *mtk_dp = dev_get_drvdata(dev);
> @@ -2658,18 +2665,29 @@ static int mtk_dp_register_audio_driver(struct device
> *dev)
> .data = mtk_dp,
> .no_capture_mute = 1,
> };
> + int ret;
>
> mtk_dp->audio_pdev = platform_device_register_data(dev,
>
> HDMI_CODEC_DRV_NAME,
>
> PLATFORM_DEVID_AUTO,
> &codec_data,
>
> sizeof(codec_data));
> - return PTR_ERR_OR_ZERO(mtk_dp->audio_pdev);
> + if (IS_ERR(mtk_dp->audio_pdev))
> + return PTR_ERR(mtk_dp->audio_pdev);
> +
> + ret = devm_add_action_or_reset(dev, mtk_dp_unregister_pdevs,
> mtk_dp->phy_dev);
Wrong platform device given here. You want audio_pdev instead.
Having briefly looked at this driver, I think it needs more cleanup. :o
ChenYu
> + if (ret) {
> + platform_device_unregister(mtk_dp->audio_pdev);
> + return dev_err_probe(dev, ret,
> + "Failed to add codec unregister devm
> action");
> + }
> + return 0;
> }
>
> static int mtk_dp_register_phy(struct mtk_dp *mtk_dp)
> {
> struct device *dev = mtk_dp->dev;
> + int ret;
>
> mtk_dp->phy_dev = platform_device_register_data(dev,
> "mediatek-dp-phy",
> PLATFORM_DEVID_AUTO,
> @@ -2679,6 +2697,13 @@ static int mtk_dp_register_phy(struct mtk_dp *mtk_dp)
> return dev_err_probe(dev, PTR_ERR(mtk_dp->phy_dev),
> "Failed to create device
> mediatek-dp-phy\n");
>
> + ret = devm_add_action_or_reset(dev, mtk_dp_unregister_pdevs,
> mtk_dp->phy_dev);
> + if (ret) {
> + platform_device_unregister(mtk_dp->phy_dev);
> + return dev_err_probe(dev, ret,
> + "Failed to add phy unregister devm
> action");
> + }
> +
> mtk_dp_get_calibration_data(mtk_dp);
>
> mtk_dp->phy = devm_phy_get(&mtk_dp->phy_dev->dev, "dp");
> @@ -2848,9 +2873,6 @@ static void mtk_dp_remove(struct platform_device *pdev)
> pm_runtime_disable(&pdev->dev);
> if (mtk_dp->data->bridge_type != DRM_MODE_CONNECTOR_eDP)
> del_timer_sync(&mtk_dp->debounce_timer);
> - platform_device_unregister(mtk_dp->phy_dev);
> - if (mtk_dp->audio_pdev)
> - platform_device_unregister(mtk_dp->audio_pdev);
> }
>
> #ifdef CONFIG_PM_SLEEP
> --
> 2.48.1
>
