From: Arnd Bergmann <arnd@arndb.de>

The newly added driver uses the backlight subsystem but is missing the
corresponding Kconfig dependency:

arm-linux-gnueabi-ld: drivers/gpu/drm/panel/panel-visionox-vtdr6130.o: in function `visionox_vtdr6130_probe':
panel-visionox-vtdr6130.c:(.text+0xdee): undefined reference to `devm_backlight_device_register'

Fixes: 65dc9360f741 ("drm: panel: Add Himax HX8394 panel controller driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/gpu/drm/panel/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index dd79928f5482..8f2046caaa6b 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -742,6 +742,7 @@ config DRM_PANEL_VISIONOX_VTDR6130
 	tristate "Visionox VTDR6130"
 	depends on OF
 	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
 	help
 	  Say Y here if you want to enable support for Visionox
 	  VTDR6130 1080x2400 AMOLED DSI panel.
-- 
2.39.0

On Tue, Jan 17, 2023 at 5:55 PM Arnd Bergmann <arnd@kernel.org> wrote:

> From: Arnd Bergmann <arnd@arndb.de>
>
> The newly added driver uses the backlight subsystem but is missing the
> corresponding Kconfig dependency:
>
> arm-linux-gnueabi-ld: drivers/gpu/drm/panel/panel-visionox-vtdr6130.o: in function `visionox_vtdr6130_probe':
> panel-visionox-vtdr6130.c:(.text+0xdee): undefined reference to `devm_backlight_device_register'
>
> Fixes: 65dc9360f741 ("drm: panel: Add Himax HX8394 panel controller driver")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Patch applied, thanks for fixing this!

Yours,
Linus Walleij

On 1/17/23 19:22, Linus Walleij wrote:
> On Tue, Jan 17, 2023 at 5:55 PM Arnd Bergmann <arnd@kernel.org> wrote:
> 
>> From: Arnd Bergmann <arnd@arndb.de>
>>
>> The newly added driver uses the backlight subsystem but is missing the
>> corresponding Kconfig dependency:
>>
>> arm-linux-gnueabi-ld: drivers/gpu/drm/panel/panel-visionox-vtdr6130.o: in function `visionox_vtdr6130_probe':
>> panel-visionox-vtdr6130.c:(.text+0xdee): undefined reference to `devm_backlight_device_register'
>>
>> Fixes: 65dc9360f741 ("drm: panel: Add Himax HX8394 panel controller driver")
>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> 
> Patch applied, thanks for fixing this!
> 
> Yours,
> Linus Walleij
>

Thanks Arnd and Linus for fixing this. Sorry that I missed it
while upstreaming the driver.

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat