[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 <luming.yu@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/acpi/ibm_acpi.c b/drivers/acpi/ibm_acpi.c
index 0fb731a470dc..6c8291c3e774 100644
--- a/drivers/acpi/ibm_acpi.c
+++ b/drivers/acpi/ibm_acpi.c
@@ -1185,6 +1185,10 @@ static int __init acpi_ibm_init(void)
         if (acpi_disabled)
                 return -ENODEV;
 
+        if (!acpi_specific_hotkey_enabled){
+                printk(IBM_ERR "Using generic hotkey driver\n");
+                return -ENODEV; 
+        }
         /* these handles are required */
         if (IBM_HANDLE_INIT(ec,   1) < 0 ||
             IBM_HANDLE_INIT(hkey, 1) < 0 ||