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3dbc80a3e4
On x86/ACPI boards the acpi_video driver will usually initialize before the kms driver (except i915). This causes /sys/class/backlight/acpi_video0 to show up and then the kms driver registers its own native backlight device after which the drivers/acpi/video_detect.c code unregisters the acpi_video0 device (when acpi_video_get_backlight_type()==native). This means that userspace briefly sees 2 devices and the disappearing of acpi_video0 after a brief time confuses the systemd backlight level save/restore code, see e.g.: https://bbs.archlinux.org/viewtopic.php?id=269920 To fix this make backlight class device registration a separate step done by a new acpi_video_register_backlight() function. The intend is for this to be called by the drm/kms driver *after* it is done setting up its own native backlight device. So that acpi_video_get_backlight_type() knows if a native backlight will be available or not at acpi_video backlight registration time, avoiding the add + remove dance. Note the new acpi_video_register_backlight() function is also called from a delayed work to ensure that the acpi_video backlight devices does get registered if necessary even if there is no drm/kms driver or when it is disabled. Changes in v2: - Make register_backlight_delay a module parameter, mainly so that it can be disabled by Nvidia binary driver users Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> |
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| .. | ||
| platform | ||
| acbuffer.h | ||
| acconfig.h | ||
| acexcep.h | ||
| acnames.h | ||
| acoutput.h | ||
| acpi.h | ||
| acpi_bus.h | ||
| acpi_drivers.h | ||
| acpi_io.h | ||
| acpi_lpat.h | ||
| acpi_numa.h | ||
| acpiosxf.h | ||
| acpixf.h | ||
| acrestyp.h | ||
| actbl.h | ||
| actbl1.h | ||
| actbl2.h | ||
| actbl3.h | ||
| actypes.h | ||
| acuuid.h | ||
| apei.h | ||
| battery.h | ||
| button.h | ||
| cppc_acpi.h | ||
| ghes.h | ||
| hed.h | ||
| nfit.h | ||
| pcc.h | ||
| pdc_intel.h | ||
| processor.h | ||
| reboot.h | ||
| video.h | ||