thinkpad-acpi: Add mute and mic-mute LED functionality

The LEDs are currently not visible to userspace, for security
reasons. They are exported through thinkpad_acpi.h for use by the
snd-hda-intel driver.

Thanks to Alex Hung <alex.hung@canonical.com> and Takashi Iwai
<tiwai@suse.de> for writing parts of this patch.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 5 insertions, 2 deletions

diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
index 86c52360ffe7..fc04c14de4bb 100644
--- a/Documentation/laptops/thinkpad-acpi.txt
+++ b/Documentation/laptops/thinkpad-acpi.txt
@@ -1,7 +1,7 @@
                      ThinkPad ACPI Extras Driver
 
-                            Version 0.24
-                        December 11th,  2009
+                            Version 0.25
+                        October 16th,  2013
 
                Borislav Deianov <borislav@users.sf.net>
              Henrique de Moraes Holschuh <hmh@hmh.eng.br>
@@ -741,6 +741,9 @@ compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled.
 Distributions must never enable this option.  Individual users that
 are aware of the consequences are welcome to enabling it.
 
+Audio mute and microphone mute LEDs are supported, but currently not
+visible to userspace. They are used by the snd-hda-intel audio driver.
+
 procfs notes:
 
 The available commands are: