On Sat, May 17, 2014 at 10:48:02AM +0200, Hans de Goede wrote: > Switch from acpi_video_unregister(), to acpi_video_unregister_backlight(), > so that the hotkeys handler registered by acpi-video stays in place. > > Since there are no mappings for the atkbd raw codes for the brightness > keys used by newer Acer models in /lib/udev/hwdb.d/60-keyboard.hwdb, and > since we map the wmi events with a code of KE_IGNORE, we rely on acpi-video > to do the hotkey handling for us. > > For laptops such as the Acer Aspire 5750 which uses intel gfx this works > despite us calling acpi_video_unregister() because the following happens: > > 1) acpi-video module gets loaded (as it is a dependency of acer-wmi and i915) > 2) acpi-video does NOT call acpi_video_register() > 3) acer-wmi loads (assume it loads before i915), calls > acpi_video_dmi_promote_vendor(); which sets ACPI_VIDEO_BACKLIGHT_DMI_VENDOR > 4) calls acpi_video_unregister -> not registered, nop > 5) i915 loads, calls acpi_video_register > 6) acpi_video_register registers the acpi_notifier for the hotkeys, > does NOT register a backlight device because of ACPI_VIDEO_BACKLIGHT_DMI_VENDOR > > But on the Acer Aspire 5750G, which uses nvidia graphics the following happens: > 1) acpi-video module gets loaded (as it is a dependency of acer-wmi) > 2) acpi-video calls acpi_video_register() > 3) acpi_video_register registers the acpi_notifier for the hotkeys, > and a backlight device > 4) acer-wmi loads, calls acpi_video_dmi_promote_vendor() > 5) calls acpi_video_unregister, this unregisters BOTH the acpi_notifier for > the hotkeys AND the backlight device > > And we end up without any handler for the brightness hotkeys. This patch fixes > this by switching over to acpi_video_unregister_backlight() which keeps the > hotkey handler in place. > > https://bugzilla.kernel.org/show_bug.cgi?id=35622 > > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> This patch is good to me. Reviewd-by: Lee, Chun-Yi <jlee@xxxxxxxx> Thanks for your patch. > --- > drivers/platform/x86/acer-wmi.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c > index c91f69b3..3a74699 100644 > --- a/drivers/platform/x86/acer-wmi.c > +++ b/drivers/platform/x86/acer-wmi.c > @@ -2228,7 +2228,7 @@ static int __init acer_wmi_init(void) > pr_info("Brightness must be controlled by acpi video driver\n"); > } else { > pr_info("Disabling ACPI video driver\n"); > - acpi_video_unregister(); > + acpi_video_unregister_backlight(); > } > > if (wmi_has_guid(WMID_GUID3)) { > -- > 1.9.0 > Joey Lee -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
