---

yaml
---
r: 84071
b: refs/heads/master
c: 01e88f2
h: refs/heads/master
i:
  84069: 480179f
  84067: 71c8b9a
  84063: 93ec068
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b7c8c200bfbf523ea0a72fd8a5e39089c74da371
+refs/heads/master: 01e88f25985d8ea5866c9a73d56b3a9a9145066f

trunk/Documentation/thinkpad-acpi.txt

@@ -215,6 +215,11 @@ The following commands can be written to the /proc/acpi/ibm/hotkey file:
 	... any other 8-hex-digit mask ...
 	echo reset > /proc/acpi/ibm/hotkey -- restore the original mask
 
+The procfs interface does not support NVRAM polling control.  So as to
+maintain maximum bug-to-bug compatibility, it does not report any masks,
+nor does it allow one to manipulate the hot key mask when the firmware
+does not support masks at all, even if NVRAM polling is in use.
+
 sysfs notes:
 
 	hotkey_bios_enabled:
@@ -231,17 +236,26 @@ sysfs notes:
 		to this value.
 
 	hotkey_enable:
-		Enables/disables the hot keys feature, and reports
-		current status of the hot keys feature.
+		Enables/disables the hot keys feature in the ACPI
+		firmware, and reports current status of the hot keys
+		feature.  Has no effect on the NVRAM hot key polling
+		functionality.
 
 		0: disables the hot keys feature / feature disabled
 		1: enables the hot keys feature / feature enabled
 
 	hotkey_mask:
-		bit mask to enable driver-handling and ACPI event
-		generation for each hot key (see above).  Returns the
-		current status of the hot keys mask, and allows one to
-		modify it.
+		bit mask to enable driver-handling (and depending on
+		the firmware, ACPI event generation) for each hot key
+		(see above).  Returns the current status of the hot keys
+		mask, and allows one to modify it.
+
+		Note: when NVRAM polling is active, the firmware mask
+		will be different from the value returned by
+		hotkey_mask.  The driver will retain enabled bits for
+		hotkeys that are under NVRAM polling even if the
+		firmware refuses them, and will not set these bits on
+		the firmware hot key mask.
 
 	hotkey_all_mask:
 		bit mask that should enable event reporting for all
@@ -257,6 +271,40 @@ sysfs notes:
 		handled by the firmware anyway.  Echo it to
 		hotkey_mask above, to use.
 
+	hotkey_source_mask:
+		bit mask that selects which hot keys will the driver
+		poll the NVRAM for.  This is auto-detected by the driver
+		based on the capabilities reported by the ACPI firmware,
+		but it can be overridden at runtime.
+
+		Hot keys whose bits are set in both hotkey_source_mask
+		and also on hotkey_mask are polled for in NVRAM.  Only a
+		few hot keys are available through CMOS NVRAM polling.
+
+		Warning: when in NVRAM mode, the volume up/down/mute
+		keys are synthesized according to changes in the mixer,
+		so you have to use volume up or volume down to unmute,
+		as per the ThinkPad volume mixer user interface.  When
+		in ACPI event mode, volume up/down/mute are reported as
+		separate events, but this behaviour may be corrected in
+		future releases of this driver, in which case the
+		ThinkPad volume mixer user interface semanthics will be
+		enforced.
+
+	hotkey_poll_freq:
+		frequency in Hz for hot key polling. It must be between
+		0 and 25 Hz.  Polling is only carried out when strictly
+		needed.
+
+		Setting hotkey_poll_freq to zero disables polling, and
+		will cause hot key presses that require NVRAM polling
+		to never be reported.
+
+		Setting hotkey_poll_freq too low will cause repeated
+		pressings of the same hot key to be misreported as a
+		single key press, or to not even be detected at all.
+		The recommended polling frequency is 10Hz.
+
 	hotkey_radio_sw:
 		if the ThinkPad has a hardware radio switch, this
 		attribute will read 0 if the switch is in the "radios
@@ -1263,3 +1311,14 @@ Sysfs interface changelog:
 		and the hwmon class for libsensors4 (lm-sensors 3)
 		compatibility.  Moved all hwmon attributes to this
 		new platform device.
+
+0x020100:	Marker for thinkpad-acpi with hot key NVRAM polling
+		support.  If you must, use it to know you should not
+		start an userspace NVRAM poller (allows to detect when
+		NVRAM is compiled out by the user because it is
+		unneeded/undesired in the first place).
+0x020101:	Marker for thinkpad-acpi with hot key NVRAM polling
+		and proper hotkey_mask semanthics (version 8 of the
+		NVRAM polling patch).  Some development snapshots of
+		0.18 had an earlier version that did strange things
+		to hotkey_mask.

trunk/drivers/misc/Kconfig

@@ -219,6 +219,25 @@ config THINKPAD_ACPI_BAY
 
 	  If you are not sure, say Y here.
 
+config THINKPAD_ACPI_HOTKEY_POLL
+	bool "Suport NVRAM polling for hot keys"
+	depends on THINKPAD_ACPI
+	default y
+	---help---
+	  Some thinkpad models benefit from NVRAM polling to detect a few of
+	  the hot key press events.  If you know your ThinkPad model does not
+	  need to do NVRAM polling to support any of the hot keys you use,
+	  unselecting this option will save about 1kB of memory.
+
+	  ThinkPads T40 and newer, R52 and newer, and X31 and newer are
+	  unlikely to need NVRAM polling in their latest BIOS versions.
+
+	  NVRAM polling can detect at most the following keys: ThinkPad/Access
+	  IBM, Zoom, Switch Display (fn+F7), ThinkLight, Volume up/down/mute,
+	  Brightness up/down, Display Expand (fn+F8), Hibernate (fn+F12).
+
+	  If you are not sure, say Y here.  The driver enables polling only if
+	  it is strictly necessary to do so.
 
 config ATMEL_SSC
 	tristate "Device driver for Atmel SSC peripheral"