Den 09.07.2018 17.20, skrev Arnd Bergmann:

This tinydrm driver fails to link without the backlight support:

drivers/gpu/drm/tinydrm/ili9341.o: In function `ili9341_probe': ili9341.c:(.text+0x578): undefined reference to `devm_of_find_backlight'

Fixes: 3fa0e8f6f960 ("drm/tinydrm: new driver for ILI9341 display panels") Signed-off-by: Arnd Bergmann arnd@arndb.de

---

drivers/gpu/drm/tinydrm/Kconfig | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig index 7a8008b0783f..16f4b5c91f1b 100644 --- a/drivers/gpu/drm/tinydrm/Kconfig +++ b/drivers/gpu/drm/tinydrm/Kconfig @@ -23,6 +23,7 @@ config TINYDRM_ILI9225 config TINYDRM_ILI9341 tristate "DRM support for ILI9341 display panels" depends on DRM_TINYDRM && SPI

• depends on BACKLIGHT_CLASS_DEVICE select TINYDRM_MIPI_DBI help DRM driver for the following Ilitek ILI9341 panels:

There was some work done to make backlight optional, but I see now that it failed to take into account the possibility of the driver being builtin and BACKLIGHT_CLASS_DEVICE being a module.

This is from include/linux/backlight.h:

#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE) struct backlight_device *of_find_backlight(struct device *dev); struct backlight_device *devm_of_find_backlight(struct device *dev); #else static inline struct backlight_device *of_find_backlight(struct device *dev) {     return NULL; }

static inline struct backlight_device * devm_of_find_backlight(struct device *dev) {     return NULL; } #endif

Anyways, thanks for fixing this: Acked-by: Noralf Trønnes noralf@tronnes.org

David Lechner do you apply this?

Noralf.