From 83ac7a1c2ed5f17caa07cbbc84bad3c05dc3bf22 Mon Sep 17 00:00:00 2001

From: Hans de Goede <hdegoede@redhat.com>

Date: Thu, 25 Aug 2022 16:13:34 +0200

Subject: [PATCH] platform/x86: msi-laptop: Fix old-ec check for backlight registering

Git-commit: 83ac7a1c2ed5f17caa07cbbc84bad3c05dc3bf22

Patch-mainline: v6.1-rc1

References: git-fixes

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

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 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 93ef8851b93e..54170172a666 100644

--- a/drivers/platform/x86/msi-laptop.c

+++ b/drivers/platform/x86/msi-laptop.c

@@ -1047,8 +1047,7 @@ 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));

-- 

2.35.3