video: stm32: remove the compatible "synopsys, dw-mipi-dsi" support

Remove the compatible "synopsys,dw-mipi-dsi" added in U-Boot
(it don't exist in Linux kernel binding); it is only used
to bind the generic synopsys UCLASS_DSI_HOST "dw_mipi_dsi" to
the driver "stm32-display-dsi" UCLASS_VIDEO_BRIDGE

This binding is done in Linux kernel drivers without compatible
(dw_mipi_dsi_bind() is called in bind of driver, for example in
drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c).

This patch does the same in U-Boot driver, the STM32 driver
calls during its bind the function device_bind_driver_to_node
to bind the generic driver "dw_mipi_dsi" at the same address.

This patch reduces the device tree differences
between Linux kernel and U-Boot for stm32mp1 platform.

Tested with v2020.01-rc1 on STM32MP157C-EV1 and STM32MP157C-DK2.

The dependency of driver is clearer and the probe order is guaranteed.

STM32MP> dm tree
 Class     Index  Probed  Driver                Name
-----------------------------------------------------------
 root          0  [ + ]   root_driver           root_driver
 sysreset      0  [   ]   syscon_reboot         |-- reboot
 simple_bus    0  [ + ]   generic_simple_bus    |-- soc
 serial        0  [ + ]   serial_stm32          |   |-- serial@40010000
...
 video_brid    0  [ + ]   stm32-display-dsi     |   |-- dsi@5a000000
 dsi_host      0  [ + ]   dw_mipi_dsi           |   |   |-- dsihost
 panel         0  [ + ]   rm68200_panel         |   |   `-- panel-dsi@0
...

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>

arch/arm/dts/stm32mp157c-dk2-u-boot.dtsi

@@ -5,13 +5,6 @@
 
 #include "stm32mp157a-dk1-u-boot.dtsi"
 
-/ {
-	dsi_host: dsi_host {
-		compatible = "synopsys,dw-mipi-dsi";
-		status = "okay";
-	};
-};
-
 &i2c1 {
 	hdmi-transmitter@39 {
 		reset-gpios = <&gpioa 10 GPIO_ACTIVE_LOW>;

arch/arm/dts/stm32mp157c-ev1-u-boot.dtsi

@@ -14,11 +14,6 @@
 		spi0 = &qspi;
 		usb0 = &usbotg_hs;
 	};
-
-	dsi_host: dsi_host {
-		compatible = "synopsys,dw-mipi-dsi";
-		status = "okay";
-	};
 };
 
 &flash0 {

drivers/video/dw_mipi_dsi.c

@@ -816,15 +816,9 @@ static int dw_mipi_dsi_probe(struct udevice *dev)
 	return 0;
 }
 
-static const struct udevice_id dw_mipi_dsi_ids[] = {
-	{ .compatible = "synopsys,dw-mipi-dsi" },
-	{ }
-};
-
 U_BOOT_DRIVER(dw_mipi_dsi) = {
 	.name			= "dw_mipi_dsi",
 	.id			= UCLASS_DSI_HOST,
-	.of_match		= dw_mipi_dsi_ids,
 	.probe			= dw_mipi_dsi_probe,
 	.ops			= &dw_mipi_dsi_ops,
 	.priv_auto_alloc_size	= sizeof(struct dw_mipi_dsi),

drivers/video/stm32/stm32_dsi.c

@@ -20,6 +20,7 @@
 #include <asm/io.h>
 #include <asm/arch/gpio.h>
 #include <dm/device-internal.h>
+#include <dm/lists.h>
 #include <linux/iopoll.h>
 #include <power/regulator.h>
 
@@ -399,6 +400,18 @@ static int stm32_dsi_set_backlight(struct udevice *dev, int percent)
 	return 0;
 }
 
+static int stm32_dsi_bind(struct udevice *dev)
+{
+	int ret;
+
+	ret = device_bind_driver_to_node(dev, "dw_mipi_dsi", "dsihost",
+					 dev_ofnode(dev), NULL);
+	if (ret)
+		return ret;
+
+	return dm_scan_fdt_dev(dev);
+}
+
 static int stm32_dsi_probe(struct udevice *dev)
 {
 	struct stm32_dsi_priv *priv = dev_get_priv(dev);
@@ -483,7 +496,7 @@ U_BOOT_DRIVER(stm32_dsi) = {
 	.name				= "stm32-display-dsi",
 	.id				= UCLASS_VIDEO_BRIDGE,
 	.of_match			= stm32_dsi_ids,
-	.bind				= dm_scan_fdt_dev,
+	.bind				= stm32_dsi_bind,
 	.probe				= stm32_dsi_probe,
 	.ops				= &stm32_dsi_ops,
 	.priv_auto_alloc_size		= sizeof(struct stm32_dsi_priv),