[ACPI] generic Hot Key support

See Documentation/acpi-hotkey.txt

Use cmdline "acpi_specific_hotkey" to enable
legacy platform specific drivers.

http://bugzilla.kernel.org/show_bug.cgi?id=3887

Signed-off-by: Luming Yu <[email protected]>
Signed-off-by: Len Brown <[email protected]>

Documentation/acpi-hotkey.txt

@@ -0,0 +1,35 @@
+driver/acpi/hotkey.c implement:
+1. /proc/acpi/hotkey/event_config 
+(event based hotkey or event config interface):
+a. add a  event based hotkey(event) : 
+echo "0:bus::action:method:num:num" > event_config
+
+b. delete a event based hotkey(event): 
+echo "1:::::num:num" > event_config
+
+c.  modify a event based hotkey(event):    
+echo "2:bus::action:method:num:num" > event_config
+
+2. /proc/acpi/hotkey/poll_config 
+(polling based hotkey or event config interface):
+a.add a polling based hotkey(event) : 	
+echo "0:bus:method:action:method:num" > poll_config
+this adding command will create a proc file 
+/proc/acpi/hotkey/method, which is used to get 
+result of polling.
+
+b.delete a polling based hotkey(event): 	
+echo "1:::::num" > event_config
+
+c.modify a polling based hotkey(event):    
+echo "2:bus:method:action:method:num" > poll_config
+
+3./proc/acpi/hotkey/action 
+(interface to call aml method associated with a 
+specific hotkey(event))
+echo "event_num:event_type:event_argument" > 
+	/proc/acpi/hotkey/action.
+The result of the execution of this aml method is 
+attached to /proc/acpi/hotkey/poll_method, which is dnyamically
+created.  Please use command "cat /proc/acpi/hotkey/polling_method" 
+to retrieve it.

drivers/acpi/Kconfig

@@ -123,6 +123,15 @@ config ACPI_VIDEO
 	  Note that this is an ref. implementation only.  It may or may not work
 	  for your integrated video device.
 
+config ACPI_HOTKEY
+	tristate "Generic Hotkey"
+	depends on ACPI_INTERPRETER
+	depends on EXPERIMENTAL
+	depends on !IA64_SGI_SN
+	default m
+	help
+	ACPI generic hotkey
+
 config ACPI_FAN
 	tristate "Fan"
 	depends on !IA64_SGI_SN

drivers/acpi/Makefile

@@ -42,7 +42,8 @@ obj-$(CONFIG_ACPI_BATTERY)	+= battery.o
 obj-$(CONFIG_ACPI_BUTTON)	+= button.o
 obj-$(CONFIG_ACPI_EC)		+= ec.o
 obj-$(CONFIG_ACPI_FAN)		+= fan.o
-obj-$(CONFIG_ACPI_VIDEO)	+= video.o
+obj-$(CONFIG_ACPI_VIDEO)	+= video.o 
+obj-$(CONFIG_ACPI_HOTKEY)	+= hotkey.o
 obj-$(CONFIG_ACPI_PCI)		+= pci_root.o pci_link.o pci_irq.o pci_bind.o
 obj-$(CONFIG_ACPI_POWER)	+= power.o
 obj-$(CONFIG_ACPI_PROCESSOR)	+= processor.o

drivers/acpi/asus_acpi.c

@@ -1204,6 +1204,10 @@ static int __init asus_acpi_init(void)
 	if (acpi_disabled)
 		return -ENODEV;
 
+	if (!acpi_specific_hotkey_enabled){
+		printk(KERN_ERR "Using generic hotkey driver\n");
+		return -ENODEV;	
+	}
 	asus_proc_dir = proc_mkdir(PROC_ASUS, acpi_root_dir);
 	if (!asus_proc_dir) {
 		printk(KERN_ERR "Asus ACPI: Unable to create /proc entry\n");