queue-4.19/acpi-video-extend-chassis-type-detection-with-a-lunc.patch

   1 From cf8fa97911a7dcc1ff2a3fb35fcb9fd06212f6e4 Mon Sep 17 00:00:00 2001
   2 From: Hans de Goede <hdegoede@redhat.com>
   3 Date: Mon, 7 Jan 2019 17:08:21 +0100
   4 Subject: ACPI / video: Extend chassis-type detection with a "Lunch Box" check
   5
   6 [ Upstream commit d693c008e3ca04db5916ff72e68ce661888a913b ]
   7
   8 Commit 53fa1f6e8a59 ("ACPI / video: Only default only_lcd to true on
   9 Win8-ready _desktops_") introduced chassis type detection, limiting the
  10 lcd_only check for the backlight to devices where the chassis-type
  11 indicates their is no builtin LCD panel.
  12
  13 The purpose of the lcd_only check is to avoid advertising a backlight
  14 interface on desktops, since skylake and newer machines seem to always
  15 have a backlight interface even if there is no LCD panel. The limiting
  16 of this check to desktops only was done to avoid breaking backlight
  17 support on some laptops which do not have the lcd flag set.
  18
  19 The Fujitsu ESPRIMO Q910 which is a compact (NUC like) desktop machine
  20 has a chassis type of 0x10 aka "Lunch Box". Without the lcd_only check
  21 we end up falsely advertising backlight/brightness control on this
  22 device. This commit extend the dmi_is_desktop check to return true
  23 for type 0x10 to fix this.
  24
  25 Fixes: 53fa1f6e8a59 ("ACPI / video: Only default only_lcd to true ...")
  26 Signed-off-by: Hans de Goede <hdegoede@redhat.com>
  27 Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  28 Signed-off-by: Sasha Levin <sashal@kernel.org>
  29 ---
  30  drivers/acpi/acpi_video.c | 1 +
  31  1 file changed, 1 insertion(+)
  32
  33 diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
  34 index 1ab1460c4a4e..d73afb562ad9 100644
  35 --- a/drivers/acpi/acpi_video.c
  36 +++ b/drivers/acpi/acpi_video.c
  37 @@ -2143,6 +2143,7 @@ static bool dmi_is_desktop(void)
  38         case 0x05: /* Pizza Box */
  39         case 0x06: /* Mini Tower */
  40         case 0x07: /* Tower */
  41 +       case 0x10: /* Lunch Box */
  42         case 0x11: /* Main Server Chassis */
  43                 return true;
  44         }
  45 --
  46 2.19.1
  47