drivers/leds/leds-lp5521.c: fix lp5521_read() error handling

commit 5bc9ad774c063f6b41965e7314f2c26aa5e465a0 upstream.

Gcc 4.6.2 complains that:

  drivers/leds/leds-lp5521.c: In function `lp5521_load_program':
  drivers/leds/leds-lp5521.c:214:21: warning: `mode' may be used uninitialized in this function [-Wuninitialized]
  drivers/leds/leds-lp5521.c: In function `lp5521_probe':
  drivers/leds/leds-lp5521.c:788:5: warning: `buf' may be used uninitialized in this function [-Wuninitialized]
  drivers/leds/leds-lp5521.c:740:6: warning: `ret' may be used uninitialized in this function [-Wuninitialized]

These are real problems if lp5521_read() returns an error.  When that
happens we should handle it, instead of ignoring it or doing a bitwise
OR with all the other error codes and continuing.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Milo <Milo.Kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/leds/leds-lp5521.c b/drivers/leds/leds-lp5521.c
index 47771ad..bf5cfd7 100644 (file)
--- a/drivers/leds/leds-lp5521.c
+++ b/drivers/leds/leds-lp5521.c
@@ -198,9 +198,14 @@ static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
 
        /* move current engine to direct mode and remember the state */
        ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
+       if (ret)
+               return ret;
+
        /* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
        usleep_range(1000, 2000);
-       ret |= lp5521_read(client, LP5521_REG_OP_MODE, &mode);
+       ret = lp5521_read(client, LP5521_REG_OP_MODE, &mode);
+       if (ret)
+               return ret;
 
        /* For loading, all the engines to load mode */
        lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
@@ -216,8 +221,7 @@ static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
                                LP5521_PROG_MEM_SIZE,
                                pattern);
 
-       ret |= lp5521_write(client, LP5521_REG_OP_MODE, mode);
-       return ret;
+       return lp5521_write(client, LP5521_REG_OP_MODE, mode);
 }
 
 static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
@@ -693,7 +697,7 @@ static int __devinit lp5521_probe(struct i2c_client *client,
         * LP5521_REG_ENABLE register will not have any effect - strange!
         */
        ret = lp5521_read(client, LP5521_REG_R_CURRENT, &buf);
-       if (buf != LP5521_REG_R_CURR_DEFAULT) {
+       if (ret || buf != LP5521_REG_R_CURR_DEFAULT) {
                dev_err(&client->dev, "error in resetting chip\n");
                goto fail2;
        }