[3.16.y-ckt stable] Patch "iio:ad5064: Make sure ad5064_i2c_write() returns 0 on success" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    iio:ad5064: Make sure ad5064_i2c_write() returns 0 on success

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt22.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From d42be56050d722c4a41e45b25c7e8f85495a6b3f Mon Sep 17 00:00:00 2001
From: Michael Hennerich <michael.hennerich at analog.com>
Date: Tue, 13 Oct 2015 18:15:37 +0200
Subject: iio:ad5064: Make sure ad5064_i2c_write() returns 0 on success

commit 03fe472ef33b7f31fbd11d300dbb3fdab9c00fd4 upstream.

i2c_master_send() returns the number of bytes transferred on success while
the ad5064 driver expects that the write() callback returns 0 on success.
Fix that by translating any non negative return value of i2c_master_send()
to 0.

Fixes: commit 6a17a0768f77 ("iio:dac:ad5064: Add support for the ad5629r and ad5669r")
Signed-off-by: Michael Hennerich <michael.hennerich at analog.com>
Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
Signed-off-by: Jonathan Cameron <jic23 at kernel.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/iio/dac/ad5064.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/dac/ad5064.c b/drivers/iio/dac/ad5064.c
index f03b92fd3803..1b43069ca5f6 100644
--- a/drivers/iio/dac/ad5064.c
+++ b/drivers/iio/dac/ad5064.c
@@ -598,10 +598,16 @@ static int ad5064_i2c_write(struct ad5064_state *st, unsigned int cmd,
 	unsigned int addr, unsigned int val)
 {
 	struct i2c_client *i2c = to_i2c_client(st->dev);
+	int ret;

 	st->data.i2c[0] = (cmd << 4) | addr;
 	put_unaligned_be16(val, &st->data.i2c[1]);
-	return i2c_master_send(i2c, st->data.i2c, 3);
+
+	ret = i2c_master_send(i2c, st->data.i2c, 3);
+	if (ret < 0)
+		return ret;
+
+	return 0;
 }

 static int ad5064_i2c_probe(struct i2c_client *i2c,