From 7f908d332dc48a12436725ae326d6143a1a02c1c Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Fri, 15 Apr 2022 22:25:01 +0200 Subject: drm/nouveau: Don't register backlight when another backlight should be used (v2) Before this commit when we want userspace to use the acpi_video backlight device we register both the GPU's native backlight device and acpi_video's firmware acpi_video# backlight device. This relies on userspace preferring firmware type backlight devices over native ones. Registering 2 backlight devices for a single display really is undesirable, don't register the GPU's native backlight device when another backlight device should be used. Changes in v2: - Add nouveau_acpi_video_backlight_use_native() wrapper to avoid unresolved symbol errors on non X86 Reviewed-by: Lyude Paul Signed-off-by: Hans de Goede --- drivers/gpu/drm/nouveau/nouveau_acpi.c | 5 +++++ drivers/gpu/drm/nouveau/nouveau_acpi.h | 2 ++ drivers/gpu/drm/nouveau/nouveau_backlight.c | 6 ++++++ 3 files changed, 13 insertions(+) diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c index 6140db756d06..1592c9cd7750 100644 --- a/drivers/gpu/drm/nouveau/nouveau_acpi.c +++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c @@ -386,3 +386,8 @@ nouveau_acpi_edid(struct drm_device *dev, struct drm_connector *connector) return kmemdup(edid, EDID_LENGTH, GFP_KERNEL); } + +bool nouveau_acpi_video_backlight_use_native(void) +{ + return acpi_video_backlight_use_native(); +} diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.h b/drivers/gpu/drm/nouveau/nouveau_acpi.h index 330f9b837066..3c666c30dfca 100644 --- a/drivers/gpu/drm/nouveau/nouveau_acpi.h +++ b/drivers/gpu/drm/nouveau/nouveau_acpi.h @@ -11,6 +11,7 @@ void nouveau_register_dsm_handler(void); void nouveau_unregister_dsm_handler(void); void nouveau_switcheroo_optimus_dsm(void); void *nouveau_acpi_edid(struct drm_device *, struct drm_connector *); +bool nouveau_acpi_video_backlight_use_native(void); #else static inline bool nouveau_is_optimus(void) { return false; }; static inline bool nouveau_is_v1_dsm(void) { return false; }; @@ -18,6 +19,7 @@ static inline void nouveau_register_dsm_handler(void) {} static inline void nouveau_unregister_dsm_handler(void) {} static inline void nouveau_switcheroo_optimus_dsm(void) {} static inline void *nouveau_acpi_edid(struct drm_device *dev, struct drm_connector *connector) { return NULL; } +static inline bool nouveau_acpi_video_backlight_use_native(void) { return true; } #endif #endif diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c index a2141d3d9b1d..d2b8f8c13db4 100644 --- a/drivers/gpu/drm/nouveau/nouveau_backlight.c +++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c @@ -38,6 +38,7 @@ #include "nouveau_reg.h" #include "nouveau_encoder.h" #include "nouveau_connector.h" +#include "nouveau_acpi.h" static struct ida bl_ida; #define BL_NAME_SIZE 15 // 12 for name + 2 for digits + 1 for '\0' @@ -405,6 +406,11 @@ nouveau_backlight_init(struct drm_connector *connector) goto fail_alloc; } + if (!nouveau_acpi_video_backlight_use_native()) { + NV_INFO(drm, "Skipping nv_backlight registration\n"); + goto fail_alloc; + } + if (!nouveau_get_backlight_name(backlight_name, bl)) { NV_ERROR(drm, "Failed to retrieve a unique name for the backlight interface\n"); goto fail_alloc; -- cgit v1.2.3-59-g8ed1b