Despite our heuristics to not wrongly export a non working ACPI backlight interface on desktop machines, we still end up exporting one on desktops using a motherboard from the MSI MS-7721 series. I've looked at improving the heuristics, but in this case a quirk seems to be the only way to solve this. While at it also add a comment to separate the video_detect_force_none entries in the video_detect_dmi_table from other type of entries, as we already do for the other entry types. Cc: stable@xxxxxxxxxxxxxxx BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1783786 Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/acpi/video_detect.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 31014c7d3793..e63fd7bfd3a5 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -336,6 +336,11 @@ static const struct dmi_system_id video_detect_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"), }, }, + + /* + * Desktops which falsely report a backlight and which our heuristics + * for this do not catch. + */ { .callback = video_detect_force_none, .ident = "Dell OptiPlex 9020M", @@ -344,6 +349,14 @@ static const struct dmi_system_id video_detect_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"), }, }, + { + .callback = video_detect_force_none, + .ident = "MSI MS-7721", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "MSI"), + DMI_MATCH(DMI_PRODUCT_NAME, "MS-7721"), + }, + }, { }, }; -- 2.23.0