[media] media: adv7180: increase delay after reset to 5ms
authorUlrich Hecht <ulrich.hecht+renesas@gmail.com>
Tue, 10 Nov 2015 13:39:00 +0000 (11:39 -0200)
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>
Tue, 17 Nov 2015 16:56:59 +0000 (14:56 -0200)
Initialization of the ADV7180 chip fails on the Renesas R8A7790-based
Lager board about 50% of the time.  This patch resolves the issue by
increasing the minimum delay after reset from 2 ms to 5 ms, following the
recommendation in the ADV7180 datasheet:

"Executing a software reset takes approximately 2 ms. However, it is
recommended to wait 5 ms before any further I2C writes are performed."

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
drivers/media/i2c/adv7180.c

index f82c8aa164fa8266a73a647820a02a9ab56fc964..3c3c4bfe386644a7afda9d1ecebd1b891737d202 100644 (file)
@@ -1112,7 +1112,7 @@ static int init_device(struct adv7180_state *state)
        mutex_lock(&state->mutex);
 
        adv7180_write(state, ADV7180_REG_PWR_MAN, ADV7180_PWR_MAN_RES);
-       usleep_range(2000, 10000);
+       usleep_range(5000, 10000);
 
        ret = state->chip_info->init(state);
        if (ret)