dm: test: Add a test for the mmc uclass

Add a test to confirm that we can probe this device. Since there is no
MMC stack support in sandbox at present, this is as far as the test goes.

Signed-off-by: Simon Glass <sjg@chromium.org>

test/dm/Makefile

@@ -19,6 +19,7 @@ obj-$(CONFIG_CLK) += clk.o
 obj-$(CONFIG_DM_ETH) += eth.o
 obj-$(CONFIG_DM_GPIO) += gpio.o
 obj-$(CONFIG_DM_I2C) += i2c.o
+obj-$(CONFIG_DM_MMC) += mmc.o
 obj-$(CONFIG_DM_PCI) += pci.o
 obj-$(CONFIG_RAM) += ram.o
 obj-$(CONFIG_RESET) += reset.o

test/dm/mmc.c

@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <mmc.h>
+#include <dm/test.h>
+#include <test/ut.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * Basic test of the mmc uclass. We could expand this by implementing an MMC
+ * stack for sandbox, or at least implementing the basic operation.
+ */
+static int dm_test_mmc_base(struct unit_test_state *uts)
+{
+	struct udevice *dev;
+
+	ut_assertok(uclass_get_device(UCLASS_MMC, 0, &dev));
+
+	return 0;
+}
+DM_TEST(dm_test_mmc_base, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);