[3.8.y.z extended stable] Patch "rtc-cmos: Add an alarm disable quirk" has been added to staging queue

[Kamal Mostafa]

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

    rtc-cmos: Add an alarm disable quirk

to the linux-3.8.y-queue branch of the 3.8.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-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.18.

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

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From cb23a8e0d0a883445822dd9ae476832ba1608b47 Mon Sep 17 00:00:00 2001
From: Borislav Petkov <bp at alien8.de>
Date: Sat, 20 Jul 2013 19:00:23 +0200
Subject: rtc-cmos: Add an alarm disable quirk

commit d5a1c7e3fc38d9c7d629e1e47f32f863acbdec3d upstream.

41c7f7424259f ("rtc: Disable the alarm in the hardware (v2)") added the
functionality to disable the RTC wake alarm when shutting down the box.

However, there are at least two b0rked BIOSes we know about:

https://bugzilla.novell.com/show_bug.cgi?id=812592
https://bugzilla.novell.com/show_bug.cgi?id=805740

where, when wakeup alarm is enabled in the BIOS, the machine reboots
automatically right after shutdown, regardless of what wakeup time is
programmed.

Bisecting the issue lead to this patch so disable its functionality with
a DMI quirk only for those boxes.

Cc: Brecht Machiels <brecht at mos6581.org>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: John Stultz <john.stultz at linaro.org>
Cc: Rabin Vincent <rabin.vincent at stericsson.com>
Signed-off-by: Borislav Petkov <bp at suse.de>
[jstultz: Changed variable name for clarity, added extra dmi entry]
Tested-by: Brecht Machiels <brecht at mos6581.org>
Tested-by: Borislav Petkov <bp at suse.de>
Signed-off-by: John Stultz <john.stultz at linaro.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/rtc/rtc-cmos.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 51 insertions(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 1c77423..e5fd432 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -34,11 +34,11 @@
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
 #include <linux/platform_device.h>
-#include <linux/mod_devicetable.h>
 #include <linux/log2.h>
 #include <linux/pm.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
+#include <linux/dmi.h>

 /* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
 #include <asm-generic/rtc.h>
@@ -377,6 +377,51 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 	return 0;
 }

+/*
+ * Do not disable RTC alarm on shutdown - workaround for b0rked BIOSes.
+ */
+static bool alarm_disable_quirk;
+
+static int __init set_alarm_disable_quirk(const struct dmi_system_id *id)
+{
+	alarm_disable_quirk = true;
+	pr_info("rtc-cmos: BIOS has alarm-disable quirk. ");
+	pr_info("RTC alarms disabled\n");
+	return 0;
+}
+
+static const struct dmi_system_id rtc_quirks[] __initconst = {
+	/* https://bugzilla.novell.com/show_bug.cgi?id=805740 */
+	{
+		.callback = set_alarm_disable_quirk,
+		.ident    = "IBM Truman",
+		.matches  = {
+			DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "4852570"),
+		},
+	},
+	/* https://bugzilla.novell.com/show_bug.cgi?id=812592 */
+	{
+		.callback = set_alarm_disable_quirk,
+		.ident    = "Gigabyte GA-990XA-UD3",
+		.matches  = {
+			DMI_MATCH(DMI_SYS_VENDOR,
+					"Gigabyte Technology Co., Ltd."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "GA-990XA-UD3"),
+		},
+	},
+	/* http://permalink.gmane.org/gmane.linux.kernel/1604474 */
+	{
+		.callback = set_alarm_disable_quirk,
+		.ident    = "Toshiba Satellite L300",
+		.matches  = {
+			DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Satellite L300"),
+		},
+	},
+	{}
+};
+
 static int cmos_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
 	struct cmos_rtc	*cmos = dev_get_drvdata(dev);
@@ -385,6 +430,9 @@ static int cmos_alarm_irq_enable(struct device *dev, unsigned int enabled)
 	if (!is_valid_irq(cmos->irq))
 		return -EINVAL;

+	if (alarm_disable_quirk)
+		return 0;
+
 	spin_lock_irqsave(&rtc_lock, flags);

 	if (enabled)
@@ -1166,6 +1214,8 @@ static int __init cmos_init(void)
 			platform_driver_registered = true;
 	}

+	dmi_check_system(rtc_quirks);
+
 	if (retval == 0)
 		return 0;

--
1.8.3.2