[3.19.y-ckt stable] Patch "i2c: mux: Use __i2c_transfer() instead of calling parent's master_xfer()" has been added to staging queue

[Kamal Mostafa]

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

    i2c: mux: Use __i2c_transfer() instead of calling parent's master_xfer()

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.y-ckt4.

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

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 5f22f4fa77e1e4d7f90dee9235203cf5539220f1 Mon Sep 17 00:00:00 2001
From: Alexander Sverdlin <alexander.sverdlin at nokia.com>
Date: Fri, 12 Jun 2015 14:40:37 +0200
Subject: i2c: mux: Use __i2c_transfer() instead of calling parent's
 master_xfer()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

commit e766f338a74200b8104b1165776b19f56e252834 upstream.

Newly introduced quirks infrastructure doesn't work for the devices behind
MUXes because MUX's master_xfer() calls parent's master_xfer() directly
without checking the quirks. Instead of duplicating check code in MUX just
call __i2c_transfer() instead. This has a side effect on tracing (messages
will appear on both MUX bus and parent bus), but maybe that's not bad at
the end.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin at nokia.com>
Tested-by: Łukasz Gemborowski <lukasz.gemborowski at nokia.com>
Signed-off-by: Wolfram Sang <wsa at the-dreams.de>
Fixes: b7f625840267b1 ("i2c: add quirk checks to core")
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/i2c/i2c-mux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 06cc1ff..98dd5d4 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -51,7 +51,7 @@ static int i2c_mux_master_xfer(struct i2c_adapter *adap,

 	ret = priv->select(parent, priv->mux_priv, priv->chan_id);
 	if (ret >= 0)
-		ret = parent->algo->master_xfer(parent, msgs, num);
+		ret = __i2c_transfer(parent, msgs, num);
 	if (priv->deselect)
 		priv->deselect(parent, priv->mux_priv, priv->chan_id);

--
1.9.1