save and restore adaptive keyboard mode for suspend and,resume

Dan Aloni has submitted a patch to set adaptive mode to function mode
when system resume back. Thanks Dan. :)

Following patch can make it to be restored to previous mode like What
Windows does.

Thanks,
Shuduo

>From 0ca960138518ceab23110141a0d7c0cafd54a859 Mon Sep 17 00:00:00 2001
From: Shuduo Sang <shuduo.sang@canonical.com>
Date: Thu, 27 Mar 2014 17:51:24 +0800
Subject: [PATCH] save and restore adaptive keyboard mode for suspend and
 resume

The mode of adaptive keyboard on X1 Carbon need be saved first before
suspend then it can be restored after resume. Otherwise it will be
unusable.

Signed-off-by: Bruce Ma <bruce.ma@canonical.com>
Signed-off-by: Shuduo Sang <shuduo.sang@canonical.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

drivers/platform/x86/thinkpad_acpi.c

@@ -3830,13 +3830,28 @@ static void hotkey_notify(struct ibm_struct *ibm, u32 event)
 
 static void hotkey_suspend(void)
 {
+	int hkeyv;
+
 	/* Do these on suspend, we get the events on early resume! */
 	hotkey_wakeup_reason = TP_ACPI_WAKEUP_NONE;
 	hotkey_autosleep_ack = 0;
+
+	/* save previous mode of adaptive keyboard of X1 Carbon */
+	if (acpi_evalf(hkey_handle, &hkeyv, "MHKV", "qd")) {
+		if ((hkeyv >> 8) == 2) {
+			if (!acpi_evalf(hkey_handle,
+						&adaptive_keyboard_prev_mode,
+						"GTRW", "dd", 0)) {
+				pr_err("Cannot read adaptive keyboard mode.\n");
+			}
+		}
+	}
 }
 
 static void hotkey_resume(void)
 {
+	int hkeyv;
+
 	tpacpi_disable_brightness_delay();
 
 	if (hotkey_status_set(true) < 0 ||
@@ -3849,6 +3864,18 @@ static void hotkey_resume(void)
 	hotkey_wakeup_reason_notify_change();
 	hotkey_wakeup_hotunplug_complete_notify_change();
 	hotkey_poll_setup_safe(false);
+
+	/* restore previous mode of adapive keyboard of X1 Carbon */
+	if (acpi_evalf(hkey_handle, &hkeyv, "MHKV", "qd")) {
+		if ((hkeyv >> 8) == 2) {
+			if (!acpi_evalf(hkey_handle,
+						NULL,
+						"STRW", "vd",
+						adaptive_keyboard_prev_mode)) {
+				pr_err("Cannot set adaptive keyboard mode.\n");
+			}
+		}
+	}
 }
 
 /* procfs -------------------------------------------------------------- */