dm: Add a dsi host uclass

Display Serial Interface (DSI) host can usefully be modelled
as their own uclass.
DSI defines a serial bus and a communication protocol
between the host and the device (panel, bridge).

Signed-off-by: Yannick Fertré <yannick.fertre@st.com>
diff --git a/test/dm/Makefile b/test/dm/Makefile
index 55a7940..0c2fd5c 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -18,6 +18,7 @@
 obj-$(CONFIG_BOARD) += board.o
 obj-$(CONFIG_DM_BOOTCOUNT) += bootcount.o
 obj-$(CONFIG_CLK) += clk.o clk_ccf.o
+obj-$(CONFIG_VIDEO_MIPI_DSI) += dsi_host.o
 obj-$(CONFIG_DM_ETH) += eth.o
 obj-$(CONFIG_FIRMWARE) += firmware.o
 obj-$(CONFIG_DM_GPIO) += gpio.o
diff --git a/test/dm/dsi_host.c b/test/dm/dsi_host.c
new file mode 100644
index 0000000..59fcd55
--- /dev/null
+++ b/test/dm/dsi_host.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * Copyright (C) 2019 STMicroelectronics - All Rights Reserved
+ * Author(s): Yannick Fertre <yannick.fertre@st.com> for STMicroelectronics.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dsi_host.h>
+#include <asm/state.h>
+#include <asm/test.h>
+#include <dm/test.h>
+#include <test/ut.h>
+
+static int dm_test_dsi_host_phy_init(void *priv_data)
+{
+	return 0;
+}
+
+static void dm_test_dsi_host_phy_post_set_mode(void *priv_data,
+					       unsigned long mode_flags)
+{
+}
+
+static int dm_test_dsi_host_phy_get_lane_mbps(void *priv_data,
+					      struct display_timing *timings,
+					      u32 lanes,
+					      u32 format,
+					      unsigned int *lane_mbps)
+{
+	return 0;
+}
+
+static const struct mipi_dsi_phy_ops dm_test_dsi_host_phy_ops = {
+	.init = dm_test_dsi_host_phy_init,
+	.get_lane_mbps = dm_test_dsi_host_phy_get_lane_mbps,
+	.post_set_mode = dm_test_dsi_host_phy_post_set_mode,
+};
+
+/* Test that dsi_host driver functions are called */
+static int dm_test_dsi_host(struct unit_test_state *uts)
+{
+	struct udevice *dev;
+	struct mipi_dsi_device device;
+	struct display_timing timings;
+	unsigned int max_data_lanes = 4;
+
+	ut_assertok(uclass_first_device_err(UCLASS_DSI_HOST, &dev));
+
+	ut_assertok(dsi_host_init(dev, &device, &timings, max_data_lanes,
+				  &dm_test_dsi_host_phy_ops));
+
+	ut_assertok(dsi_host_enable(dev));
+
+	return 0;
+}
+
+DM_TEST(dm_test_dsi_host, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);