[ 3.5.y.z extended stable ] Patch "x86, 8042: Enable A20 using KBC to fix S3 resume on" has been added to staging queue

[Herton Ronaldo Krzesinski]

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

    x86, 8042: Enable A20 using KBC to fix S3 resume on

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

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

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Herton

------

>From 1c2a54da3ff8be8d21aebf1d6fc5e5a91d2098af Mon Sep 17 00:00:00 2001
From: Ondrej Zary <linux at rainbow-software.org>
Date: Tue, 11 Dec 2012 22:18:05 +0100
Subject: [PATCH 09/27] x86, 8042: Enable A20 using KBC to fix S3 resume on
 some MSI laptops

commit ad68652412276f68ad4fe3e1ecf5ee6880876783 upstream.

Some MSI laptop BIOSes are broken - INT 15h code uses port 92h to enable A20
line but resume code assumes that KBC was used.
The laptop will not resume from S3 otherwise but powers off after a while
and then powers on again stuck with a blank screen.

Fix it by enabling A20 using KBC in i8042_platform_init for x86.

Fixes https://bugzilla.kernel.org/show_bug.cgi?id=12878

Signed-off-by: Ondrej Zary <linux at rainbow-software.org>
Cc: Dmitry Torokhov <dmitry.torokhov at gmail.com>
Cc: Alan Cox <alan at lxorguk.ukuu.org.uk>
Cc: Rafael J. Wysocki <rjw at sisk.pl>
Link: http://lkml.kernel.org/r/201212112218.06551.linux@rainbow-software.org
Signed-off-by: H. Peter Anvin <hpa at linux.intel.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 drivers/input/serio/i8042-x86ia64io.h |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/input/serio/i8042-x86ia64io.h b/drivers/input/serio/i8042-x86ia64io.h
index d6cc77a..5f306f7 100644
--- a/drivers/input/serio/i8042-x86ia64io.h
+++ b/drivers/input/serio/i8042-x86ia64io.h
@@ -921,6 +921,7 @@ static int __init i8042_platform_init(void)
 	int retval;

 #ifdef CONFIG_X86
+	u8 a20_on = 0xdf;
 	/* Just return if pre-detection shows no i8042 controller exist */
 	if (!x86_platform.i8042_detect())
 		return -ENODEV;
@@ -960,6 +961,14 @@ static int __init i8042_platform_init(void)

 	if (dmi_check_system(i8042_dmi_dritek_table))
 		i8042_dritek = true;
+
+	/*
+	 * A20 was already enabled during early kernel init. But some buggy
+	 * BIOSes (in MSI Laptops) require A20 to be enabled using 8042 to
+	 * resume from S3. So we do it here and hope that nothing breaks.
+	 */
+	i8042_command(&a20_on, 0x10d1);
+	i8042_command(NULL, 0x00ff);	/* Null command for SMM firmware */
 #endif /* CONFIG_X86 */

 	return retval;
--
1.7.9.5