@@ -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;
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@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@rainbow-software.org> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Rafael J. Wysocki <rjw@sisk.pl> Link: http://lkml.kernel.org/r/201212112218.06551.linux@rainbow-software.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> --- drivers/input/serio/i8042-x86ia64io.h | 9 +++++++++ 1 file changed, 9 insertions(+) -- 1.7.9.5