Making FB_BACKLIGHT tristate by commit b4a1ed0cd18b ("fbdev: make FB_BACKLIGHT a tristate") caused unmet dependencies in some configurations:
WARNING: unmet direct dependencies detected for FB_BACKLIGHT Depends on [m]: HAS_IOMEM [=y] && FB [=m] Selected by [y]: - DRM_NOUVEAU [=y] && HAS_IOMEM [=y] && DRM [=y] && PCI [=y] && MMU [=y] && DRM_NOUVEAU_BACKLIGHT [=y] Selected by [m]: - FB_NVIDIA [=m] && HAS_IOMEM [=y] && FB [=m] && PCI [=y] && FB_NVIDIA_BACKLIGHT [=y]
Fix it by making DRM_NOUVEAU select BACKLIGHT_CLASS_DEVICE and BACKLIGHT_LCD_SUPPORT instead of FB_BACKLIGHT.
Fixes: b4a1ed0cd18b ("fbdev: make FB_BACKLIGHT a tristate") Reported-by: Randy Dunlap rdunlap@infradead.org Cc: Rob Clark robdclark@gmail.com Cc: Arnd Bergmann arnd@arndb.de Cc: Ben Skeggs bskeggs@redhat.com Cc: David Airlie airlied@linux.ie Cc: Daniel Vetter daniel@ffwll.ch Cc: Stephen Rothwell sfr@canb.auug.org.au Signed-off-by: Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com --- I would like to merge this patch through fbdev tree for v4.21 (as it is needed to fix commit currently in fbdev tree).
drivers/gpu/drm/nouveau/Kconfig | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
Index: b/drivers/gpu/drm/nouveau/Kconfig =================================================================== --- a/drivers/gpu/drm/nouveau/Kconfig 2018-11-30 11:46:55.716464505 +0100 +++ b/drivers/gpu/drm/nouveau/Kconfig 2018-12-28 14:54:51.655965845 +0100 @@ -4,7 +4,8 @@ config DRM_NOUVEAU select FW_LOADER select DRM_KMS_HELPER select DRM_TTM - select FB_BACKLIGHT if DRM_NOUVEAU_BACKLIGHT + select BACKLIGHT_CLASS_DEVICE if DRM_NOUVEAU_BACKLIGHT + select BACKLIGHT_LCD_SUPPORT if DRM_NOUVEAU_BACKLIGHT select ACPI_VIDEO if ACPI && X86 && BACKLIGHT_CLASS_DEVICE && INPUT select X86_PLATFORM_DEVICES if ACPI && X86 select ACPI_WMI if ACPI && X86