From: Giedrius Statkevičius <giedrius.statkevicius@gmail.com>
Date: Sat, 16 Apr 2016 00:27:12 +0000 (+0300)
Subject: asus-laptop: correct error handling in asus_read_brightness()
X-Git-Tag: v4.7-rc1~30^2~12
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=198b618ab118c7d856278a985de1ed0eff77c02f;p=thirdparty%2Fkernel%2Flinux.git

asus-laptop: correct error handling in asus_read_brightness()

It is possible that acpi_evaluate_integer might fail and value would not be
set to any value so correct this defect by returning 0 in case of an
error. This is also the correct thing to return because the backlight
subsystem will print the old value of brightness in this case.

Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---

diff --git a/drivers/platform/x86/asus-laptop.c b/drivers/platform/x86/asus-laptop.c
index f2b5d0a8adf03..a4cd78691ac93 100644
--- a/drivers/platform/x86/asus-laptop.c
+++ b/drivers/platform/x86/asus-laptop.c
@@ -775,8 +775,10 @@ static int asus_read_brightness(struct backlight_device *bd)
 
 	rv = acpi_evaluate_integer(asus->handle, METHOD_BRIGHTNESS_GET,
 				   NULL, &value);
-	if (ACPI_FAILURE(rv))
+	if (ACPI_FAILURE(rv)) {
 		pr_warn("Error reading brightness\n");
+		return 0;
+	}
 
 	return value;
 }