serdev: only match serdev devices

jhovold · gregkh · commit 7ee69102dbc4 · 2018-01-22T14:19:10.000+01:00
Only serdev devices (a.k.a. clients or slaves) are bound to drivers so
bail out early from match() in case the device is not a serdev device
(i.e. if it's a serdev controller).

Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Reviewed-by: Sebastian Reichel &lt;sebastian.reichel@collabora.co.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
@@ -63,6 +63,11 @@ static const struct device_type serdev_device_type = {
 	.release	= serdev_device_release,
 };
 
+static bool is_serdev_device(const struct device *dev)
+{
+	return dev->type == &serdev_device_type;
+}
+
 static void serdev_ctrl_release(struct device *dev)
 {
 	struct serdev_controller *ctrl = to_serdev_controller(dev);
@@ -76,6 +81,9 @@ static const struct device_type serdev_ctrl_type = {
 
 static int serdev_device_match(struct device *dev, struct device_driver *drv)
 {
+	if (!is_serdev_device(dev))
+		return 0;
+
 	/* TODO: platform matching */
 	if (acpi_driver_match_device(dev, drv))
 		return 1;
