Fix oinkmaster patch.

[ipfire-2.x.git] / src / patches / suse-2.6.27.39 / patches.arch / acpi-dock-don-t-eval-_sta-on-every-show_docked-sysfs-read.patch

From 1d672ef324e78a467603ef55aa4558cac9f895ba Mon Sep 17 00:00:00 2001
From: Holger Macht <hmacht@suse.de>
Date: Tue, 20 Jan 2009 12:18:24 +0100
Subject: ACPI: dock: Don't eval _STA on every show_docked sysfs read

From: Holger Macht <hmacht@suse.de>

commit fc5a9f8841ee87d93376ada5d73117d4d6a373ea upstream.

Some devices trigger a DEVICE_CHECK on every evalutation of _STA. This
can also be seen in commit 8b59560a3baf2e7c24e0fb92ea5d09eca92805db
(ACPI: dock: avoid check _STA method).  If an undock is processed, the
dock driver sends a uevent and userspace might read the show_docked
property in sysfs. This causes an evaluation of _STA of the particular
device which causes the dock driver to immediately dock again.

In any case, evaluation of _STA (show_docked) does not necessarily mean
that we are docked, so check with the internal device structure.

http://bugzilla.kernel.org/show_bug.cgi?id=12360

Signed-off-by: Holger Macht <hmacht@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/acpi/dock.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/acpi/dock.c
+++ b/drivers/acpi/dock.c
@@ -854,8 +854,14 @@ fdd_out:
 static ssize_t show_docked(struct device *dev,
 			   struct device_attribute *attr, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%d\n", dock_present(dock_station));
+	struct acpi_device *tmp;
 
+	struct dock_station *dock_station = *((struct dock_station **)
+		dev->platform_data);
+
+	if (ACPI_SUCCESS(acpi_bus_get_device(dock_station->handle, &tmp)))
+		return snprintf(buf, PAGE_SIZE, "1\n");
+	return snprintf(buf, PAGE_SIZE, "0\n");
 }
 static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);