linux-kernel - [PATCH v2] backlight: pwm_bl: Don't assign levels table repeatedly

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Date:   Wed,  2 Oct 2019 09:56:01 -0700
From:   Matthias Kaehlcke <mka@...omium.org>
To:     Thierry Reding <thierry.reding@...il.com>,
        Lee Jones <lee.jones@...aro.org>,
        Daniel Thompson <daniel.thompson@...aro.org>,
        Jingoo Han <jingoohan1@...il.com>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
Cc:     Matthias Kaehlcke <mka@...omium.org>, linux-pwm@...r.kernel.org,
        linux-fbdev@...r.kernel.org, dri-devel@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH v2] backlight: pwm_bl: Don't assign levels table repeatedly

pwm_backlight_probe() re-assigns pb->levels for every brightness
level. This is not needed and was likely not intended, since
neither side of the assignment changes during the loop. Assign
the field only once.

Signed-off-by: Matthias Kaehlcke <mka@...omium.org>
---

Changes in v2:
- removed curly braces from for loop

 drivers/video/backlight/pwm_bl.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
index 746eebc411df..05d3b3802658 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -564,18 +564,17 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	memset(&props, 0, sizeof(struct backlight_properties));
 
 	if (data->levels) {
+		pb->levels = data->levels;
+
 		/*
 		 * For the DT case, only when brightness levels is defined
 		 * data->levels is filled. For the non-DT case, data->levels
 		 * can come from platform data, however is not usual.
 		 */
-		for (i = 0; i <= data->max_brightness; i++) {
+		for (i = 0; i <= data->max_brightness; i++)
 			if (data->levels[i] > pb->scale)
 				pb->scale = data->levels[i];
 
-			pb->levels = data->levels;
-		}
-
 		if (pwm_backlight_is_linear(data))
 			props.scale = BACKLIGHT_SCALE_LINEAR;
 		else
-- 
2.23.0.444.g18eeb5a265-goog