acpi_video_set_dmi_backlight_type() is troublesome because it may end up getting called after other backlight drivers have already called acpi_video_get_backlight_type() resulting in the other drivers already being registered even though they should not. In case of the acpi_video backlight, acpi_video_set_dmi_backlight_type() actually calls acpi_video_unregister_backlight() since that is often probed earlier, leading to userspace seeing the acpi_video0 class device being briefly available, leading to races in userspace where udev probe-rules try to access the device and it is already gone. In case of toshiba_acpi there are no DMI quirks to move to acpi/video_detect.c, but it also (ab)uses it for transflective displays. Adding transflective display support to video_detect.c would be quite involved. But luckily there are only 2 known models with a transflective display, so we can just add DMI quirks for those. Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/acpi/video_detect.c | 19 +++++++++++++++++++ drivers/platform/x86/toshiba_acpi.c | 16 ---------------- 2 files changed, 19 insertions(+), 16 deletions(-) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index be2fc43418af..74e2087c8ff0 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -190,6 +190,25 @@ static const struct dmi_system_id video_detect_dmi_table[] = { }, }, + /* + * Toshiba models with Transflective display, these need to use + * the toshiba_acpi vendor driver for proper Transflective handling. + */ + { + .callback = video_detect_force_vendor, + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"), + DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R500"), + }, + }, + { + .callback = video_detect_force_vendor, + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"), + DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R600"), + }, + }, + /* * These models have a working acpi_video backlight control, and using * native backlight causes a regression where backlight does not work diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c index 0fc9e8b8827b..030dc37d50b8 100644 --- a/drivers/platform/x86/toshiba_acpi.c +++ b/drivers/platform/x86/toshiba_acpi.c @@ -271,14 +271,6 @@ static const struct key_entry toshiba_acpi_alt_keymap[] = { { KE_END, 0 }, }; -/* - * List of models which have a broken acpi-video backlight interface and thus - * need to use the toshiba (vendor) interface instead. - */ -static const struct dmi_system_id toshiba_vendor_backlight_dmi[] = { - {} -}; - /* * Utility */ @@ -2881,14 +2873,6 @@ static int toshiba_acpi_setup_backlight(struct toshiba_acpi_dev *dev) return 0; } - /* - * Tell acpi-video-detect code to prefer vendor backlight on all - * systems with transflective backlight and on dmi matched systems. - */ - if (dev->tr_backlight_supported || - dmi_check_system(toshiba_vendor_backlight_dmi)) - acpi_video_set_dmi_backlight_type(acpi_backlight_vendor); - if (acpi_video_get_backlight_type() != acpi_backlight_vendor) return 0; -- 2.37.2