drivers/video/backlight/adp88x0_bl.c: fix bit testing logic

We need to write new value if the bit mask fields of new value is not
equal to old value.  It does not make sense to write new value only when
all the bit_mask bits are zero.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/video/backlight/adp8860_bl.c b/drivers/video/backlight/adp8860_bl.c
index 66bc74d9ce2af30889d026835d00442923cbc822..378276c9d3cfdaa2926740da3aa6faba5213a3ae 100644 (file)
--- a/drivers/video/backlight/adp8860_bl.c
+++ b/drivers/video/backlight/adp8860_bl.c
@@ -146,7 +146,7 @@ static int adp8860_set_bits(struct i2c_client *client, int reg, uint8_t bit_mask
 
        ret = adp8860_read(client, reg, &reg_val);
 
-       if (!ret && ((reg_val & bit_mask) == 0)) {
+       if (!ret && ((reg_val & bit_mask) != bit_mask)) {
                reg_val |= bit_mask;
                ret = adp8860_write(client, reg, reg_val);
        }

diff --git a/drivers/video/backlight/adp8870_bl.c b/drivers/video/backlight/adp8870_bl.c
index 6c68a6899e8769c0f131c91860e3467240bcb87c..6735059376d63840d95067ee4564500cd70fe390 100644 (file)
--- a/drivers/video/backlight/adp8870_bl.c
+++ b/drivers/video/backlight/adp8870_bl.c
@@ -160,7 +160,7 @@ static int adp8870_set_bits(struct i2c_client *client, int reg, uint8_t bit_mask
 
        ret = adp8870_read(client, reg, &reg_val);
 
-       if (!ret && ((reg_val & bit_mask) == 0)) {
+       if (!ret && ((reg_val & bit_mask) != bit_mask)) {
                reg_val |= bit_mask;
                ret = adp8870_write(client, reg, reg_val);
        }