This is a note to let you know that I've just added the patch titled drm/panel: novatek-nt35950: Improve error handling to the 6.2-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-panel-novatek-nt35950-improve-error-handling.patch and it can be found in the queue-6.2 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e4840c9d2815080b545afcc21e0b2b690bd83587 Author: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> Date: Sat Apr 15 13:00:30 2023 +0200 drm/panel: novatek-nt35950: Improve error handling [ Upstream commit 5dd45b66742a1f3cfa9a92dc0ac8714c7708ee6c ] In a very peculiar case when probing and registering with the secondary DSI host succeeds, but the OF backlight or DSI attachment fails, the primary DSI device is automatically cleaned up, but the secondary one is not, leading to -EEXIST when the driver core tries to handle -EPROBE_DEFER. Unregister the DSI1 device manually on failure to prevent that. Fixes: 623a3531e9cf ("drm/panel: Add driver for Novatek NT35950 DSI DriverIC panels") Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> Reviewed-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx> Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20230415-konrad-longbois-next-v1-1-ce695dc9df84@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/panel/panel-novatek-nt35950.c b/drivers/gpu/drm/panel/panel-novatek-nt35950.c index 3a844917da075..4359b02754aac 100644 --- a/drivers/gpu/drm/panel/panel-novatek-nt35950.c +++ b/drivers/gpu/drm/panel/panel-novatek-nt35950.c @@ -593,8 +593,11 @@ static int nt35950_probe(struct mipi_dsi_device *dsi) DRM_MODE_CONNECTOR_DSI); ret = drm_panel_of_backlight(&nt->panel); - if (ret) + if (ret) { + mipi_dsi_device_unregister(nt->dsi[1]); + return dev_err_probe(dev, ret, "Failed to get backlight\n"); + } drm_panel_add(&nt->panel); @@ -610,6 +613,9 @@ static int nt35950_probe(struct mipi_dsi_device *dsi) ret = mipi_dsi_attach(nt->dsi[i]); if (ret < 0) { + /* If we fail to attach to either host, we're done */ + mipi_dsi_device_unregister(nt->dsi[1]); + return dev_err_probe(dev, ret, "Cannot attach to DSI%d host.\n", i); }