[3.16.y-ckt stable] Patch "mfd: tc6393xb: Fail ohci suspend if full state restore is required" has been added to staging queue

[Luis Henriques]

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

    mfd: tc6393xb: Fail ohci suspend if full state restore is required

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?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-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 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 49346c4da10dba78fae20679d1ee0a50ebb24358 Mon Sep 17 00:00:00 2001
From: Dmitry Eremin-Solenikov <dbaryshkov at gmail.com>
Date: Fri, 24 Oct 2014 21:19:57 +0400
Subject: mfd: tc6393xb: Fail ohci suspend if full state restore is required

commit 1a5fb99de4850cba710d91becfa2c65653048589 upstream.

Some boards with TC6393XB chip require full state restore during system
resume thanks to chip's VCC being cut off during suspend (Sharp SL-6000
tosa is one of them). Failing to do so would result in ohci Oops on
resume due to internal memory contentes being changed. Fail ohci suspend
on tc6393xb is full state restore is required.

Recommended workaround is to unbind tmio-ohci driver before suspend and
rebind it after resume.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov at gmail.com>
Signed-off-by: Lee Jones <lee.jones at linaro.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/mfd/tc6393xb.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/mfd/tc6393xb.c b/drivers/mfd/tc6393xb.c
index 11c19e538551..48579e5ef02c 100644
--- a/drivers/mfd/tc6393xb.c
+++ b/drivers/mfd/tc6393xb.c
@@ -263,6 +263,17 @@ static int tc6393xb_ohci_disable(struct platform_device *dev)
 	return 0;
 }

+static int tc6393xb_ohci_suspend(struct platform_device *dev)
+{
+	struct tc6393xb_platform_data *tcpd = dev_get_platdata(dev->dev.parent);
+
+	/* We can't properly store/restore OHCI state, so fail here */
+	if (tcpd->resume_restore)
+		return -EBUSY;
+
+	return tc6393xb_ohci_disable(dev);
+}
+
 static int tc6393xb_fb_enable(struct platform_device *dev)
 {
 	struct tc6393xb *tc6393xb = dev_get_drvdata(dev->dev.parent);
@@ -403,7 +414,7 @@ static struct mfd_cell tc6393xb_cells[] = {
 		.num_resources = ARRAY_SIZE(tc6393xb_ohci_resources),
 		.resources = tc6393xb_ohci_resources,
 		.enable = tc6393xb_ohci_enable,
-		.suspend = tc6393xb_ohci_disable,
+		.suspend = tc6393xb_ohci_suspend,
 		.resume = tc6393xb_ohci_enable,
 		.disable = tc6393xb_ohci_disable,
 	},
--
2.1.4