From 6b0076540faffd47f5a899bf12f3528c4f0e726b Mon Sep 17 00:00:00 2001 From: Lyude Paul Date: Fri, 4 Feb 2022 13:05:04 -0500 Subject: [PATCH] drm/nouveau/backlight: Fix LVDS backlight detection on some laptops It seems that some laptops will report having both an eDP and LVDS connector, even though only the LVDS connector is actually hooked up. This can lead to issues with backlight registration if the eDP connector ends up getting registered before the LVDS connector, as the backlight device will then be registered to the eDP connector instead of the LVDS connector. So, fix this by only registering the backlight on connectors that are reported as being connected. Signed-off-by: Lyude Paul Fixes: 6eca310e8924 ("drm/nouveau/kms/nv50-: Add basic DPCD backlight support for nouveau") Bugzilla: https://gitlab.freedesktop.org/drm/nouveau/-/issues/137 Cc: # v5.15+ Reviewed-by: Karol Herbst Link: https://patchwork.freedesktop.org/patch/msgid/20220204180504.328999-1-lyude@redhat.com --- drivers/gpu/drm/nouveau/nouveau_backlight.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c index ae2f2ab..6af12dc 100644 --- a/drivers/gpu/drm/nouveau/nouveau_backlight.c +++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c @@ -294,7 +294,8 @@ nv50_backlight_init(struct nouveau_backlight *bl, struct nouveau_drm *drm = nouveau_drm(nv_encoder->base.base.dev); struct nvif_object *device = &drm->client.device.object; - if (!nvif_rd32(device, NV50_PDISP_SOR_PWM_CTL(ffs(nv_encoder->dcb->or) - 1))) + if (!nvif_rd32(device, NV50_PDISP_SOR_PWM_CTL(ffs(nv_encoder->dcb->or) - 1)) || + nv_conn->base.status != connector_status_connected) return -ENODEV; if (nv_conn->type == DCB_CONNECTOR_eDP) { -- 2.7.4