asus-wmi: Add callback for hotkey filtering

This is required for the T101MT home key, which behaves differently
than other hotkeys.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Corentin Chary <corentin.chary@gmail.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

drivers/platform/x86/asus-wmi.c

@@ -1061,6 +1061,8 @@ static void asus_wmi_notify(u32 value, void *context)
 	acpi_status status;
 	int code;
 	int orig_code;
+	unsigned int key_value = 1;
+	bool autorelease = 1;
 
 	status = wmi_get_event_data(value, &response);
 	if (status != AE_OK) {
@@ -1076,6 +1078,13 @@ static void asus_wmi_notify(u32 value, void *context)
 	code = obj->integer.value;
 	orig_code = code;
 
+	if (asus->driver->key_filter) {
+		asus->driver->key_filter(asus->driver, &code, &key_value,
+					 &autorelease);
+		if (code == ASUS_WMI_KEY_IGNORE)
+			goto exit;
+	}
+
 	if (code >= NOTIFY_BRNUP_MIN && code <= NOTIFY_BRNUP_MAX)
 		code = NOTIFY_BRNUP_MIN;
 	else if (code >= NOTIFY_BRNDOWN_MIN &&
@@ -1085,7 +1094,8 @@ static void asus_wmi_notify(u32 value, void *context)
 	if (code == NOTIFY_BRNUP_MIN || code == NOTIFY_BRNDOWN_MIN) {
 		if (!acpi_video_backlight_support())
 			asus_wmi_backlight_notify(asus, orig_code);
-	} else if (!sparse_keymap_report_event(asus->inputdev, code, 1, true))
+	} else if (!sparse_keymap_report_event(asus->inputdev, code,
+					       key_value, autorelease))
 		pr_info("Unknown key %x pressed\n", code);
 
 exit:

drivers/platform/x86/asus-wmi.h

@@ -29,6 +29,8 @@
 
 #include <linux/platform_device.h>
 
+#define ASUS_WMI_KEY_IGNORE (-1)
+
 struct module;
 struct key_entry;
 struct asus_wmi;
@@ -44,6 +46,10 @@ struct asus_wmi_driver {
 	const struct key_entry	*keymap;
 	const char		*input_name;
 	const char		*input_phys;
+	/* Returns new code, value, and autorelease values in arguments.
+	 * Return ASUS_WMI_KEY_IGNORE in code if event should be ignored. */
+	void (*key_filter) (struct asus_wmi_driver *driver, int *code,
+			    unsigned int *value, bool *autorelease);
 
 	int (*probe) (struct platform_device *device);
 	void (*quirks) (struct asus_wmi_driver *driver);