platform/x86: nvidia-wmi-ec-backlight: Use acpi_video_get_backlight_type()

Add an acpi_video_get_backlight_type() == acpi_backlight_nvidia_wmi_ec
check. This will make nvidia-wmi-ec-backlight properly honor the user
selecting a different backlight driver through the acpi_backlight=...
kernel commandline option.

Since the auto-detect code check for nvidia-wmi-ec-backlight in
drivers/acpi/video_detect.c already checks that the WMI advertised
brightness-source is the embedded controller, this new check makes it
unnecessary for nvidia_wmi_ec_backlight_probe() to check this itself.

Suggested-by: Daniel Dadap <ddadap@nvidia.com>
Reviewed-by: Daniel Dadap <ddadap@nvidia.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
This commit is contained in:
Hans de Goede 2022-08-17 14:37:21 +02:00
parent 21245df307
commit 8d0ca287fd
2 changed files with 4 additions and 11 deletions

View File

@ -93,6 +93,7 @@ config PEAQ_WMI
config NVIDIA_WMI_EC_BACKLIGHT
tristate "EC Backlight Driver for Hybrid Graphics Notebook Systems"
depends on ACPI_VIDEO
depends on ACPI_WMI
depends on BACKLIGHT_CLASS_DEVICE
help

View File

@ -10,6 +10,7 @@
#include <linux/platform_data/x86/nvidia-wmi-ec-backlight.h>
#include <linux/types.h>
#include <linux/wmi.h>
#include <acpi/video.h>
/**
* wmi_brightness_notify() - helper function for calling WMI-wrapped ACPI method
@ -87,19 +88,10 @@ static int nvidia_wmi_ec_backlight_probe(struct wmi_device *wdev, const void *ct
{
struct backlight_properties props = {};
struct backlight_device *bdev;
u32 source;
int ret;
ret = wmi_brightness_notify(wdev, WMI_BRIGHTNESS_METHOD_SOURCE,
WMI_BRIGHTNESS_MODE_GET, &source);
if (ret)
return ret;
/*
* This driver is only to be used when brightness control is handled
* by the EC; otherwise, the GPU driver(s) should control brightness.
*/
if (source != WMI_BRIGHTNESS_SOURCE_EC)
/* drivers/acpi/video_detect.c also checks that SOURCE == EC */
if (acpi_video_get_backlight_type() != acpi_backlight_nvidia_wmi_ec)
return -ENODEV;
/*