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| author | Hans de Goede <hdegoede@redhat.com> | 2023-02-17 15:42:08 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-02-25 11:13:29 +0100 |
| commit | c75a91216f2ef326d631622e3c93d0bf394da123 (patch) | |
| tree | 38cb63214de49c8421c517a56761362720e750ee | |
| parent | bae1b851d0a187069f7ea6014b2fe6b3ee2ded50 (diff) | |
| download | linux-stable-c75a91216f2ef326d631622e3c93d0bf394da123.tar.gz linux-stable-c75a91216f2ef326d631622e3c93d0bf394da123.tar.bz2 linux-stable-c75a91216f2ef326d631622e3c93d0bf394da123.zip | |
platform/x86: nvidia-wmi-ec-backlight: Add force module parameter
commit 0d9bdd8a550170306c2021b8d6766c5343b870c2 upstream.
On some Lenovo Legion models, the backlight might be driven by either
one of nvidia_wmi_ec_backlight or amdgpu_bl0 at different times.
When the Nvidia WMI EC backlight interface reports the backlight is
controlled by the EC, the current backlight handling only registers
nvidia_wmi_ec_backlight (and registers no other backlight interfaces).
This hides (never registers) the amdgpu_bl0 interface, where as prior
to 6.1.4 users would have both nvidia_wmi_ec_backlight and amdgpu_bl0
and could work around things in userspace.
Add a force module parameter which can be used with acpi_backlight=native
to restore the old behavior as a workound (for now) by passing:
"acpi_backlight=native nvidia-wmi-ec-backlight.force=1"
Fixes: 8d0ca287fd8c ("platform/x86: nvidia-wmi-ec-backlight: Use acpi_video_get_backlight_type()")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217026
Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Daniel Dadap <ddadap@nvidia.com>
Link: https://lore.kernel.org/r/20230217144208.5721-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/platform/x86/nvidia-wmi-ec-backlight.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/platform/x86/nvidia-wmi-ec-backlight.c b/drivers/platform/x86/nvidia-wmi-ec-backlight.c index baccdf658538..1b572c90c76e 100644 --- a/drivers/platform/x86/nvidia-wmi-ec-backlight.c +++ b/drivers/platform/x86/nvidia-wmi-ec-backlight.c @@ -12,6 +12,10 @@ #include <linux/wmi.h> #include <acpi/video.h> +static bool force; +module_param(force, bool, 0444); +MODULE_PARM_DESC(force, "Force loading (disable acpi_backlight=xxx checks"); + /** * wmi_brightness_notify() - helper function for calling WMI-wrapped ACPI method * @w: Pointer to the struct wmi_device identified by %WMI_BRIGHTNESS_GUID @@ -91,7 +95,7 @@ static int nvidia_wmi_ec_backlight_probe(struct wmi_device *wdev, const void *ct int ret; /* drivers/acpi/video_detect.c also checks that SOURCE == EC */ - if (acpi_video_get_backlight_type() != acpi_backlight_nvidia_wmi_ec) + if (!force && acpi_video_get_backlight_type() != acpi_backlight_nvidia_wmi_ec) return -ENODEV; /* |