hp-wmi: Add support for SMBus hotkeys

Several models of HP laptops using the same DSDT have hotkey buttons
that do not work until the EC is configured to enable them.
Signed-off-by: NKyle Evans <kvans32@gmail.com>
Signed-off-by: NMatthew Garrett <matthew.garrett@nebula.com>

drivers/platform/x86/hp-wmi.c

@@ -138,6 +138,7 @@ static const struct key_entry hp_wmi_keymap[] = {
 	{ KE_KEY, 0x2142, { KEY_MEDIA } },
 	{ KE_KEY, 0x213b, { KEY_INFO } },
 	{ KE_KEY, 0x2169, { KEY_DIRECTION } },
+	{ KE_KEY, 0x216a, { KEY_SETUP } },
 	{ KE_KEY, 0x231b, { KEY_HELP } },
 	{ KE_END, 0 }
 };
@@ -926,6 +927,9 @@ static int __init hp_wmi_init(void)
 		err = hp_wmi_input_setup();
 		if (err)
 			return err;
+		
+		//Enable magic for hotkeys that run on the SMBus
+		ec_write(0xe6,0x6e);
 	}
 
 	if (bios_capable) {