Patch "i2c: at91: ensure state is restored after suspending" has been added to the 4.9-stable tree

Patch "i2c: at91: ensure state is restored after suspending" has been added to the 4.9-stable tree

[gregkh]

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

    i2c: at91: ensure state is restored after suspending

to the 4.9-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:
     i2c-at91-ensure-state-is-restored-after-suspending.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Oct 19 15:04:02 CEST 2017
From: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Date: Thu, 16 Feb 2017 18:27:59 +0100
Subject: i2c: at91: ensure state is restored after suspending

From: Alexandre Belloni <alexandre.belloni@free-electrons.com>


[ Upstream commit e3ccc921b7d8fd1fcd10a00720e09823d8078666 ]

When going to suspend, the I2C registers may be lost because the power to
VDDcore is cut. Restore them when resuming.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/i2c/busses/i2c-at91.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -1180,6 +1180,7 @@ static int at91_twi_suspend_noirq(struct
 
 static int at91_twi_resume_noirq(struct device *dev)
 {
+	struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
 	int ret;
 
 	if (!pm_runtime_status_suspended(dev)) {
@@ -1191,6 +1192,8 @@ static int at91_twi_resume_noirq(struct
 	pm_runtime_mark_last_busy(dev);
 	pm_request_autosuspend(dev);
 
+	at91_init_twi_bus(twi_dev);
+
 	return 0;
 }
 


Patches currently in stable-queue which might be from alexandre.belloni@free-electrons.com are

queue-4.9/i2c-at91-ensure-state-is-restored-after-suspending.patch