[kernel] re-create ACPI battery sysfs files on resume from suspend

[Kyle McMartin]

commit 1121f6ddf0ae873b09f67eb45ce6c57ed6d9e81d
Author: Kyle McMartin <kyle at redhat.com>
Date:   Wed Mar 23 09:42:21 2011 -0400

    re-create ACPI battery sysfs files on resume from suspend
    
    Fixes the upstream changes to the dropped
    acpi-update-battery-information-on-notification-0x81.patch.

 ...ribble-sysfs-files-from-a-resume-notifier.patch |   89 ++++++++++++++++++++
 kernel.spec                                        |    7 ++
 2 files changed, 96 insertions(+), 0 deletions(-)
---
diff --git a/acpi_battery-fribble-sysfs-files-from-a-resume-notifier.patch b/acpi_battery-fribble-sysfs-files-from-a-resume-notifier.patch
new file mode 100644
index 0000000..b3256a2
--- /dev/null
+++ b/acpi_battery-fribble-sysfs-files-from-a-resume-notifier.patch
@@ -0,0 +1,89 @@
+From lenb at kernel.org Wed Mar 23 03:07:45 2011
+From: Len Brown <lenb at kernel.org>
+To: linux-acpi at vger.kernel.org
+Cc: Kyle McMartin <kyle at redhat.com>, Len Brown <len.brown at intel.com>
+Subject: [PATCH 35/42] ACPI battery: fribble sysfs files from a resume notifier
+Date: Wed, 23 Mar 2011 02:42:48 -0400
+
+From: Kyle McMartin <kyle at redhat.com>
+
+Commit da8aeb92 re-poked the battery on resume, but Linus reports that
+it broke his eee and partially reverted it in b23fffd7. Unfortunately
+this also results in my x201s giving crack values until the sysfs files
+are poked again. In the revert message, it was suggested that we poke it
+from a PM notifier, so let's do that.
+
+With this in place, I haven't noticed the units going nutty on my
+gnome-power-manager across a dozen suspends or so...
+
+Signed-off-by: Kyle McMartin <kyle at redhat.com>
+Acked-by: Rafael J. Wysocki <rjw at sisk.pl>
+Signed-off-by: Len Brown <len.brown at intel.com>
+---
+ drivers/acpi/battery.c |   22 ++++++++++++++++++++++
+ 1 files changed, 22 insertions(+), 0 deletions(-)
+
+diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
+index ac1a599..fcc13ac 100644
+--- a/drivers/acpi/battery.c
++++ b/drivers/acpi/battery.c
+@@ -33,6 +33,7 @@
+ #include <linux/async.h>
+ #include <linux/dmi.h>
+ #include <linux/slab.h>
++#include <linux/suspend.h>
+ 
+ #ifdef CONFIG_ACPI_PROCFS_POWER
+ #include <linux/proc_fs.h>
+@@ -102,6 +103,7 @@ struct acpi_battery {
+ 	struct mutex lock;
+ 	struct power_supply bat;
+ 	struct acpi_device *device;
++	struct notifier_block pm_nb;
+ 	unsigned long update_time;
+ 	int rate_now;
+ 	int capacity_now;
+@@ -940,6 +942,21 @@ static void acpi_battery_notify(struct acpi_device *device, u32 event)
+ 		power_supply_changed(&battery->bat);
+ }
+ 
++static int battery_notify(struct notifier_block *nb,
++			       unsigned long mode, void *_unused)
++{
++	struct acpi_battery *battery = container_of(nb, struct acpi_battery,
++						    pm_nb);
++	switch (mode) {
++	case PM_POST_SUSPEND:
++		sysfs_remove_battery(battery);
++		sysfs_add_battery(battery);
++		break;
++	}
++
++	return 0;
++}
++
+ static int acpi_battery_add(struct acpi_device *device)
+ {
+ 	int result = 0;
+@@ -972,6 +989,10 @@ static int acpi_battery_add(struct acpi_device *device)
+ #endif
+ 		kfree(battery);
+ 	}
++
++	battery->pm_nb.notifier_call = battery_notify;
++	register_pm_notifier(&battery->pm_nb);
++
+ 	return result;
+ }
+ 
+@@ -982,6 +1003,7 @@ static int acpi_battery_remove(struct acpi_device *device, int type)
+ 	if (!device || !acpi_driver_data(device))
+ 		return -EINVAL;
+ 	battery = acpi_driver_data(device);
++	unregister_pm_notifier(&battery->pm_nb);
+ #ifdef CONFIG_ACPI_PROCFS_POWER
+ 	acpi_battery_remove_fs(device);
+ #endif
+-- 
+1.7.4.1.343.ga91df
+
diff --git a/kernel.spec b/kernel.spec
index 12f2b99..3391d19 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -640,6 +640,7 @@ Patch390: linux-2.6-defaults-acpi-video.patch
 Patch391: linux-2.6-acpi-video-dos.patch
 Patch393: acpi-ec-add-delay-before-write.patch
 Patch394: linux-2.6-acpi-debug-infinite-loop.patch
+Patch399: acpi_battery-fribble-sysfs-files-from-a-resume-notifier.patch
 
 Patch450: linux-2.6-input-kill-stupid-messages.patch
 Patch452: linux-2.6.30-no-pcspkr-modalias.patch
@@ -1215,6 +1216,7 @@ ApplyPatch linux-2.6-defaults-acpi-video.patch
 ApplyPatch linux-2.6-acpi-video-dos.patch
 ApplyPatch acpi-ec-add-delay-before-write.patch
 ApplyPatch linux-2.6-acpi-debug-infinite-loop.patch
+ApplyPatch acpi_battery-fribble-sysfs-files-from-a-resume-notifier.patch
 
 # Various low-impact patches to aid debugging.
 ApplyPatch linux-2.6-debug-sizeof-structs.patch
@@ -1955,6 +1957,11 @@ fi
 
 %changelog
 * Wed Mar 23 2011 Kyle McMartin <kmcmartin at redhat.com>
+- Re-create ACPI battery sysfs files on resume from suspend, fixes the
+  upstream changes to the dropped
+  acpi-update-battery-information-on-notification-0x81.patch.
+
+* Wed Mar 23 2011 Kyle McMartin <kmcmartin at redhat.com>
 - Update to 2.6.38-git12
 - Enable I2C_DIOLAN_U2C USB i2c adapter [all], I2C_PXA [i686].