ACPI: thinkpad-acpi: add poll() support to some sysfs attributes

Implement poll()/select() support through sysfs_notify() for some key
attributes which userspace might want to poll() or select() on.

In order to let userspace know poll()/select() support is available for an
attribute, the thinkpad-acpi sysfs interface version is also bumped up.
Further changes that add poll()/select() capabilities to any pre-existing
attributes will also increment the sysfs interface version.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/Documentation/thinkpad-acpi.txt b/Documentation/thinkpad-acpi.txt
index e1c4550dac99..9bbd0f541437 100644
--- a/Documentation/thinkpad-acpi.txt
+++ b/Documentation/thinkpad-acpi.txt
@@ -311,6 +311,8 @@ sysfs notes:
                 disabled" postition, and 1 if the switch is in the
                 "radios enabled" position.
 
+                This attribute has poll()/select() support.
+
         hotkey_report_mode:
                 Returns the state of the procfs ACPI event report mode
                 filter for hot keys.  If it is set to 1 (the default),
@@ -332,6 +334,8 @@ sysfs notes:
                 undock.  Set to zero for normal wake-ups or wake-ups
                 due to unknown reasons.
 
+                This attribute has poll()/select() support.
+
         wakeup_hotunplug_complete:
                 Set to 1 if the system was waken up because of an
                 undock or bay ejection request, and that request
@@ -340,6 +344,8 @@ sysfs notes:
                 user's choice.  Refer to HKEY events 0x4003 and
                 0x3003, below.
 
+                This attribute has poll()/select() support.
+
 input layer notes:
 
 A Hot key is mapped to a single input layer EV_KEY event, possibly
@@ -1354,3 +1360,6 @@ Sysfs interface changelog:
                 NVRAM polling patch).  Some development snapshots of
                 0.18 had an earlier version that did strange things
                 to hotkey_mask.
+
+0x020200:       Add poll()/select() support to the following attributes:
+                hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason