Patch "can: sja1000: clear interrupts on start" has been added to the 3.10-stable tree

This is a note to let you know that I've just added the patch titled

can: sja1000: clear interrupts on start

to the 3.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
can-sja1000-clear-interrupts-on-start.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Mirza Krak <[email protected]>
Date: Tue, 10 Nov 2015 14:59:34 +0100
Subject: can: sja1000: clear interrupts on start

From: Mirza Krak <[email protected]>

commit 7cecd9ab80f43972c056dc068338f7bcc407b71c upstream.

According to SJA1000 data sheet error-warning (EI) interrupt is not cleared by setting the controller in to reset-mode.

Then if we have the following case:
- system is suspended (echo mem > /sys/power/state) and SJA1000 is left in operating state
- A bus error condition occurs which activates EI interrupt, system is still suspended which means EI interrupt will be not be handled nor cleared.

If the above two events occur, on resume there is no way to return the SJA1000 to operating state, except to cycle power to it.

By simply reading the IR register on start we will clear any previous conditions that could be present.

---
 drivers/net/can/sja1000/sja1000.c |    3 +++
 1 file changed, 3 insertions(+)

@@ -187,6 +187,9 @@ static void sja1000_start(struct net_dev
 	/* clear interrupt flags */
 	priv->read_reg(priv, SJA1000_IR);
 
+	/* clear interrupt flags */
+	priv->read_reg(priv, SJA1000_IR);
+
 	/* leave reset mode */
 	set_normal_mode(dev);
 }

Patches currently in stable-queue which might be from [email protected] are

queue-3.10/can-sja1000-clear-interrupts-on-start.patch