From: Amaury Decrême <amaury.decreme@gmail.com>
Date: Mon, 28 Jan 2013 21:21:07 +0000 (+0100)
Subject: i2c: sis630: fix behavior after collision
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=499b9194ad7b7b6d7c06b01005508e5bcf3c8980;p=deliverable%2Flinux.git

i2c: sis630: fix behavior after collision

Datasheet on collision:
	SMBus Collision (SMBCOL_STS)
	This bit is set when a SMBus Collision condition occurs and
	SMBus Host loses in the bus arbitration. The software should
	clear this bit and re-start SMBus operation.

As the status will be cleared in transaction_end, we can remove the
sis630_write and prepare to return -EAGAIN to retry.

Signed-off-by: Amaury Decrême <amaury.decreme@gmail.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
---

diff --git a/drivers/i2c/busses/i2c-sis630.c b/drivers/i2c/busses/i2c-sis630.c
index 3124d807c05a..e152d36b94ac 100644
--- a/drivers/i2c/busses/i2c-sis630.c
+++ b/drivers/i2c/busses/i2c-sis630.c
@@ -200,12 +200,7 @@ static int sis630_transaction_wait(struct i2c_adapter *adap, int size)
 
 	if (temp & 0x04) {
 		dev_err(&adap->dev, "Bus collision!\n");
-		result = -EIO;
-		/*
-		  TBD: Datasheet say:
-		  the software should clear this bit and restart SMBUS operation.
-		  Should we do it or user start request again?
-		*/
+		result = -EAGAIN;
 	}
 
 	return result;