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.

Suggested-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Reviewed-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 19 insertions, 18 deletions

diff --git a/drivers/video/backlight/jornada720_lcd.c b/drivers/video/backlight/jornada720_lcd.c
index da3876c9b3ae..228bc319de19 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)