ACPI / video: Add quirks for the Dell Vostro V131

The Dell Vostro V131 has an especially broken acpi-video implementation.

The backlight control bits work, but when the brightness is changed via
the acpi-video interface the backlight flickers annoyingly before settling
at the new brightness, switching to using the native interface fixes the
flickering so add a quirk for this (the vendor interface has the same
problem).

Brightness keypresses reported through the acpi-video-bus are also broken,
they get reported one event delayed, so if you press the brightness-up
hotkey on the keyboard nothing happens, then if you press brightness-down,
the previous brightness-up event gets reported. Since the keypresses are
also reported via wmi (if active) and via atkbd (when wmi is not active)
add a quirk to simply filter out the delayed (broken) events.

Reported-and-tested-by: Michał Kępień <kernel@kempniu.pl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 2971154fdd62..80b13d498091 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -419,6 +419,13 @@ static int video_enable_only_lcd(const struct dmi_system_id *d)
 	return 0;
 }
 
+static int video_set_report_key_events(const struct dmi_system_id *id)
+{
+	if (report_key_events == -1)
+		report_key_events = (uintptr_t)id->driver_data;
+	return 0;
+}
+
 static struct dmi_system_id video_dmi_table[] = {
 	/*
 	 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
@@ -507,6 +514,24 @@ static struct dmi_system_id video_dmi_table[] = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
 		},
 	},
+	/*
+	 * Some machines report wrong key events on the acpi-bus, suppress
+	 * key event reporting on these.  Note this is only intended to work
+	 * around events which are plain wrong. In some cases we get double
+	 * events, in this case acpi-video is considered the canonical source
+	 * and the events from the other source should be filtered. E.g.
+	 * by calling acpi_video_handles_brightness_key_presses() from the
+	 * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
+	 */
+	{
+	 .callback = video_set_report_key_events,
+	 .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
+	 .ident = "Dell Vostro V131",
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
+		},
+	},
 	{}
 };