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/drivers/video/dsi-host-uclass.c b/drivers/video/dsi-host-uclass.c
new file mode 100644
index 0000000..1db1f88
--- /dev/null
+++ b/drivers/video/dsi-host-uclass.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * 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>
+
+int dsi_host_init(struct udevice *dev,
+		  struct mipi_dsi_device *device,
+		  struct display_timing *timings,
+		  unsigned int max_data_lanes,
+		  const struct mipi_dsi_phy_ops *phy_ops)
+{
+	struct dsi_host_ops *ops = dsi_host_get_ops(dev);
+
+	if (!ops->init)
+		return -ENOSYS;
+
+	return ops->init(dev, device, timings, max_data_lanes, phy_ops);
+}
+
+int dsi_host_enable(struct udevice *dev)
+{
+	struct dsi_host_ops *ops = dsi_host_get_ops(dev);
+
+	if (!ops->enable)
+		return -ENOSYS;
+
+	return ops->enable(dev);
+}
+
+UCLASS_DRIVER(dsi_host) = {
+	.id		= UCLASS_DSI_HOST,
+	.name		= "dsi_host",
+};