linux-kernel - [PATCH] backlight: jornada720: Minimise code duplication and handle errors better

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <1404979626-10951-1-git-send-email-lee.jones@linaro.org>
Date:	Thu, 10 Jul 2014 09:07:06 +0100
From:	Lee Jones <lee.jones@...aro.org>
To:	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Cc:	rickard_strandqvist@...ctrumdigital.se,
	Lee Jones <lee.jones@...aro.org>, Bryan Wu <cooloney@...il.com>
Subject: [PATCH] backlight: jornada720: Minimise code duplication and handle errors better

Rickard Strandqvi's ran a code analysis application which found that
jornada_lcd_get_contrast(() and jornada_lcd_set_contrast() contained
some code duplication (calling the same functions during various
code execution paths) and failed to return errors in a consistent
manner.  This patch aims to simplify the code, coercing it into
behaving at a level expected of a driver in the Linux kernel.

Cc: Bryan Wu <cooloney@...il.com>
Suggested-by: Rickard Strandqvist <rickard_strandqvist@...ctrumdigital.se>
Acked-by: Jingoo Han <jg1.han@...sung.com>
Reviewed-by: Rickard Strandqvist <rickard_strandqvist@...ctrumdigital.se>
Signed-off-by: Lee Jones <lee.jones@...aro.org>
---
 drivers/video/backlight/jornada720_lcd.c | 37 ++++++++++++++++----------------
 1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/drivers/video/backlight/jornada720_lcd.c b/drivers/video/backlight/jornada720_lcd.c
index da3876c..228bc31 100644
--- a/drivers/video/backlight/jornada720_lcd.c
+++ b/drivers/video/backlight/jornada720_lcd.c
@@ -43,37 +43,38 @@ static int jornada_lcd_get_contrast(struct lcd_device *ld)
 
 	jornada_ssp_start();
 
-	if (jornada_ssp_byte(GETCONTRAST) != TXDUMMY) {
-		dev_err(&ld->dev, "get contrast failed\n");
-		jornada_ssp_end();
-		return -ETIMEDOUT;
-	} else {
+	if (jornada_ssp_byte(GETCONTRAST) == TXDUMMY) {
 		ret = jornada_ssp_byte(TXDUMMY);
-		jornada_ssp_end();
-		return ret;
+		goto success;
 	}
+
+	dev_err(&ld->dev, "failed to set contrast\n");
+	ret = -ETIMEDOUT;
+
+success:
+	jornada_ssp_end();
+	return ret;
 }
 
 static int jornada_lcd_set_contrast(struct lcd_device *ld, int value)
 {
-	int ret;
+	int ret = 0;
 
 	jornada_ssp_start();
 
 	/* start by sending our set contrast cmd to mcu */
-	ret = jornada_ssp_byte(SETCONTRAST);
-
-	/* push the new value */
-	if (jornada_ssp_byte(value) != TXDUMMY) {
-		dev_err(&ld->dev, "set contrast failed\n");
-		jornada_ssp_end();
-		return -ETIMEDOUT;
+	if (jornada_ssp_byte(SETCONTRAST) == TXDUMMY) {
+		/* if successful push the new value */
+		if (jornada_ssp_byte(value) == TXDUMMY)
+			goto success;
 	}
 
-	/* if we get here we can assume everything went well */
-	jornada_ssp_end();
+	dev_err(&ld->dev, "failed to set contrast\n");
+	ret = -ETIMEDOUT;
 
-	return 0;
+success:
+	jornada_ssp_end();
+	return ret;
 }
 
 static int jornada_lcd_set_power(struct lcd_device *ld, int power)
-- 
1.8.3.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/