drivers/leds/leds-lp5523.c: perform SW reset before detection
authorSamu Onkalo <samu.p.onkalo@nokia.com>
Wed, 24 Nov 2010 20:57:05 +0000 (12:57 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 24 Nov 2010 21:50:44 +0000 (06:50 +0900)
Chip detection may fail if the chip is in some odd state for example after
system restart.  Chip doesn't have HW reset line.

Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.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>
drivers/leds/leds-lp5523.c

index 4248d78cec37258e4a0df293ebd6db1737802194..0cc4ead2fd8b35cdeef653a211b40a2e885b1630 100644 (file)
@@ -203,13 +203,6 @@ static int lp5523_configure(struct i2c_client *client)
                { 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
        };
 
-       lp5523_write(client, LP5523_REG_RESET, 0xff);
-
-       usleep_range(10000, 20000); /*
-                                    * Exact value is not available. 10 - 20ms
-                                    * appears to be enough for reset.
-                                    */
-
        ret |= lp5523_write(client, LP5523_REG_ENABLE, LP5523_ENABLE);
        /* Chip startup time is 500 us, 1 - 2 ms gives some margin */
        usleep_range(1000, 2000);
@@ -941,6 +934,11 @@ static int lp5523_probe(struct i2c_client *client,
                usleep_range(1000, 2000); /* 500us abs min. */
        }
 
+       lp5523_write(client, LP5523_REG_RESET, 0xff);
+       usleep_range(10000, 20000); /*
+                                    * Exact value is not available. 10 - 20ms
+                                    * appears to be enough for reset.
+                                    */
        ret = lp5523_detect(client);
        if (ret)
                goto fail2;