Some apple laptop models have an ACPI device with a HID of APP000B and that device has an IO resource (so it does not describe the new unsupported MMIO based gmux type), but there actually is no gmux in the laptop at all. The gmux_probe() function of the actual apple-gmux driver has code to detect this, this code has been factored out into a new apple_gmux_detect() helper in apple-gmux.h. Use this new function to fix acpi_video_get_backlight_type() wrongly returning apple_gmux as type on the following laptops: MacBookPro5,4 https://pastebin.com/8Xjq7RhS MacBookPro8,1 https://linux-hardware.org/?probe=e513cfbadb&log=dmesg MacBookPro9,2 https://bugzilla.kernel.org/attachment.cgi?id=278961 MacBookPro10,2 https://lkml.org/lkml/2014/9/22/657 MacBookPro11,2 https://forums.fedora-fr.org/viewtopic.php?id=70142 MacBookPro11,4 https://raw.githubusercontent.com/im-0/investigate-card-reader-suspend-problem-on-mbp11.4/mast Fixes: 21245df307cb ("ACPI: video: Add Apple GMUX brightness control detection") Link: https://lore.kernel.org/platform-driver-x86/20230123113750.462144-1-hdegoede@xxxxxxxxxx/ Reported-by: Emmanouil Kouroupakis <kartebi@xxxxxxxxx> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- Changes in v2: - Add list of known affected Apple models (Lukas Wunner) - Add Reported-by and Link tags --- drivers/acpi/video_detect.c | 24 +++--------------------- 1 file changed, 3 insertions(+), 21 deletions(-) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 64eab35037c3..a8c02608dde4 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -110,26 +110,6 @@ static bool nvidia_wmi_ec_supported(void) } #endif -static bool apple_gmux_backlight_present(void) -{ - struct acpi_device *adev; - struct device *dev; - - adev = acpi_dev_get_first_match_dev(GMUX_ACPI_HID, NULL, -1); - if (!adev) - return false; - - dev = acpi_get_first_physical_node(adev); - if (!dev) - return false; - - /* - * drivers/platform/x86/apple-gmux.c only supports old style - * Apple GMUX with an IO-resource. - */ - return pnp_get_resource(to_pnp_dev(dev), IORESOURCE_IO, 0) != NULL; -} - /* Force to use vendor driver when the ACPI device is known to be * buggy */ static int video_detect_force_vendor(const struct dmi_system_id *d) @@ -791,6 +771,7 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) { static DEFINE_MUTEX(init_mutex); static bool nvidia_wmi_ec_present; + static bool apple_gmux_present; static bool native_available; static bool init_done; static long video_caps; @@ -804,6 +785,7 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) ACPI_UINT32_MAX, find_video, NULL, &video_caps, NULL); nvidia_wmi_ec_present = nvidia_wmi_ec_supported(); + apple_gmux_present = apple_gmux_detect(NULL, NULL); init_done = true; } if (native) @@ -825,7 +807,7 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) if (nvidia_wmi_ec_present) return acpi_backlight_nvidia_wmi_ec; - if (apple_gmux_backlight_present()) + if (apple_gmux_present) return acpi_backlight_apple_gmux; /* Use ACPI video if available, except when native should be preferred. */ -- 2.39.0