--- /dev/null
+From ff413195e830541afeae469fc866ecd0319abd7e Mon Sep 17 00:00:00 2001
+From: Alex Hung <alex.hung@canonical.com>
+Date: Tue, 24 Apr 2012 16:40:52 +0800
+Subject: thinkpad-acpi: fix issuing duplicated key events for brightness up/down
+
+From: Alex Hung <alex.hung@canonical.com>
+
+commit ff413195e830541afeae469fc866ecd0319abd7e upstream.
+
+The tp_features.bright_acpimode will not be set correctly for brightness
+control because ACPI_VIDEO_HID will not be located in ACPI. As a result,
+a duplicated key event will always be sent. acpi_video_backlight_support()
+is sufficient to detect standard ACPI brightness control.
+
+Signed-off-by: Alex Hung <alex.hung@canonical.com>
+Signed-off-by: Matthew Garrett <mjg@redhat.com>
+Cc: Andreas Sturmlechner <andreas.sturmlechner@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/platform/x86/thinkpad_acpi.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/platform/x86/thinkpad_acpi.c
++++ b/drivers/platform/x86/thinkpad_acpi.c
+@@ -3402,7 +3402,7 @@ static int __init hotkey_init(struct ibm
+ /* Do not issue duplicate brightness change events to
+ * userspace. tpacpi_detect_brightness_capabilities() must have
+ * been called before this point */
+- if (tp_features.bright_acpimode && acpi_video_backlight_support()) {
++ if (acpi_video_backlight_support()) {
+ pr_info("This ThinkPad has standard ACPI backlight "
+ "brightness control, supported by the ACPI "
+ "video driver\n");