From: Hans de Goede hdegoede@redhat.com
stable inclusion from stable-v5.10.150 commit c21c08fab716a8f8340bce66391cd99d65b14070 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0XA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 83ac7a1c2ed5f17caa07cbbc84bad3c05dc3bf22 ]
Commit 2cc6c717799f ("msi-laptop: Port to new backlight interface selection API") replaced this check:
if (!quirks->old_ec_model || acpi_video_backlight_support()) pr_info("Brightness ignored, ..."); else do_register();
With:
if (quirks->old_ec_model || acpi_video_get_backlight_type() == acpi_backlight_vendor) do_register();
But since the do_register() part was part of the else branch, the entire condition should be inverted. So not only the 2 statements on either side of the || should be inverted, but the || itself should be replaced with a &&.
In practice this has likely not been an issue because the new-ec models (old_ec_model==false) likely all support ACPI video backlight control, making acpi_video_get_backlight_type() return acpi_backlight_video turning the second part of the || also false when old_ec_model == false.
Fixes: 2cc6c717799f ("msi-laptop: Port to new backlight interface selection API") Signed-off-by: Hans de Goede hdegoede@redhat.com Link: https://lore.kernel.org/r/20220825141336.208597-1-hdegoede@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- drivers/platform/x86/msi-laptop.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/platform/x86/msi-laptop.c b/drivers/platform/x86/msi-laptop.c index 24ffc8e2d2d1..0960205ee49f 100644 --- a/drivers/platform/x86/msi-laptop.c +++ b/drivers/platform/x86/msi-laptop.c @@ -1048,8 +1048,7 @@ static int __init msi_init(void) return -EINVAL;
/* Register backlight stuff */ - - if (quirks->old_ec_model || + if (quirks->old_ec_model && acpi_video_get_backlight_type() == acpi_backlight_vendor) { struct backlight_properties props; memset(&props, 0, sizeof(struct backlight_properties));