dm: core: Add a function to get a device's uclass ID

This is useful to check which uclass a device is in.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

drivers/core/device.c

@@ -438,3 +438,8 @@ ulong dev_get_of_data(struct udevice *dev)
 {
 	return dev->of_id->data;
 }
+
+enum uclass_id device_get_uclass_id(struct udevice *dev)
+{
+	return dev->uclass->uc_drv->id;
+}

include/dm/device.h

@@ -245,6 +245,14 @@ struct udevice *dev_get_parent(struct udevice *child);
  */
 ulong dev_get_of_data(struct udevice *dev);
 
+/*
+ * device_get_uclass_id() - return the uclass ID of a device
+ *
+ * @dev:	Device to check
+ * @return uclass ID for the device
+ */
+enum uclass_id device_get_uclass_id(struct udevice *dev);
+
 /**
  * device_get_child() - Get the child of a device by index
  *

test/dm/core.c

@@ -598,3 +598,14 @@ static int dm_test_uclass_before_ready(struct dm_test_state *dms)
 }
 
 DM_TEST(dm_test_uclass_before_ready, 0);
+
+static int dm_test_device_get_uclass_id(struct dm_test_state *dms)
+{
+	struct udevice *dev;
+
+	ut_assertok(uclass_get_device(UCLASS_TEST, 0, &dev));
+	ut_asserteq(UCLASS_TEST, device_get_uclass_id(dev));
+
+	return 0;
+}
+DM_TEST(dm_test_device_get_uclass_id, DM_TESTF_SCAN_PDATA);