From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753915Ab2LKVS5 (ORCPT ); Tue, 11 Dec 2012 16:18:57 -0500 Received: from mail-1-out2.atlantis.sk ([80.94.52.71]:51165 "EHLO mail.atlantis.sk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753238Ab2LKVSz (ORCPT ); Tue, 11 Dec 2012 16:18:55 -0500 From: Ondrej Zary To: hpa@zytor.com Subject: [PATCH v4] 8042: Enable A20 using KBC to fix S3 resume on some MSI laptops Date: Tue, 11 Dec 2012 22:18:05 +0100 User-Agent: KMail/1.9.10 (enterprise35 0.20100827.1168748) Cc: Alan Cox , "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <201212112218.06551.linux@rainbow-software.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- drivers/input/serio/i8042-x86ia64io.h | 9 +++++++++ 1 files changed, 9 insertions(+), 0 deletions(-) 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; -- Ondrej Zary