usb: ehci: dm: Convert i.MX28 ehci code to driver model

This commit converts i.MX28's EHCI USB host driver to driver model
(DM_USB). It is a straightforward conversion (to reuse as much code
as possible), based on ehci-mx5.c code.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
diff --git a/drivers/usb/host/ehci-mxs.c b/drivers/usb/host/ehci-mxs.c
index aa32af1..9a61495 100644
--- a/drivers/usb/host/ehci-mxs.c
+++ b/drivers/usb/host/ehci-mxs.c
@@ -11,6 +11,8 @@
 #include <asm/arch/imx-regs.h>
 #include <errno.h>
 #include <linux/delay.h>
+#include <dm.h>
+#include <power/regulator.h>
 
 #include "ehci.h"
 
@@ -110,6 +112,7 @@
 	return ehci_mxs_toggle_clock(port, 0);
 }
 
+#if !CONFIG_IS_ENABLED(DM_USB)
 static const struct ehci_mxs_port mxs_port[] = {
 #ifdef CONFIG_EHCI_MXS_PORT0
 	{
@@ -184,3 +187,184 @@
 
 	return ret;
 }
+#else /* CONFIG_IS_ENABLED(DM_USB) */
+struct ehci_mxs_priv_data {
+	struct ehci_ctrl ctrl;
+	struct usb_ehci *ehci;
+	struct udevice *vbus_supply;
+	struct ehci_mxs_port port;
+	enum usb_init_type init_type;
+};
+
+/*
+ * Below defines correspond to imx28 clk Linux (v5.15.y)
+ * clock driver to provide proper offset for PHY[01]
+ * devices.
+ */
+#define CLK_USB_PHY0 62
+#define CLK_USB_PHY1 63
+#define PLL0CTRL0(base) ((base) + 0x0000)
+#define PLL1CTRL0(base) ((base) + 0x0020)
+
+static int ehci_usb_ofdata_to_platdata(struct udevice *dev)
+{
+	struct ehci_mxs_priv_data *priv = dev_get_priv(dev);
+	struct usb_plat *plat = dev_get_plat(dev);
+	struct ehci_mxs_port *port = &priv->port;
+	u32 phandle, phy_reg, clk_reg, clk_id;
+	ofnode phy_node, clk_node;
+	const char *mode;
+	int ret;
+
+	mode = ofnode_read_string(dev->node_, "dr_mode");
+	if (mode) {
+		if (strcmp(mode, "peripheral") == 0)
+			plat->init_type = USB_INIT_DEVICE;
+		else if (strcmp(mode, "host") == 0)
+			plat->init_type = USB_INIT_HOST;
+		else
+			return -EINVAL;
+	}
+
+	/* Read base address of the USB IP block */
+	ret = ofnode_read_u32(dev->node_, "reg", &port->usb_regs);
+	if (ret)
+		return ret;
+
+	/* Read base address of the USB PHY IP block */
+	ret = ofnode_read_u32(dev->node_, "fsl,usbphy", &phandle);
+	if (ret)
+		return ret;
+
+	phy_node = ofnode_get_by_phandle(phandle);
+	if (!ofnode_valid(phy_node))
+		return -ENODEV;
+
+	ret = ofnode_read_u32(phy_node, "reg", &phy_reg);
+	if (ret)
+		return ret;
+
+	port->phy_regs = (struct mxs_usbphy_regs *)phy_reg;
+
+	/* Read base address of the CLK IP block and proper ID */
+	ret = ofnode_read_u32_index(phy_node, "clocks", 0, &phandle);
+	if (ret)
+		return ret;
+
+	ret = ofnode_read_u32_index(phy_node, "clocks", 1, &clk_id);
+	if (ret)
+		return ret;
+
+	clk_node = ofnode_get_by_phandle(phandle);
+	if (!ofnode_valid(clk_node))
+		return -ENODEV;
+
+	ret = ofnode_read_u32(clk_node, "reg", &clk_reg);
+	if (ret)
+		return ret;
+
+	port->pll = (struct mxs_register_32 *)clk_reg;
+
+	/* Provide proper offset for USB PHY clocks */
+	if (clk_id == CLK_USB_PHY0)
+		port->pll = PLL0CTRL0(port->pll);
+
+	if (clk_id == CLK_USB_PHY1)
+		port->pll = PLL1CTRL0(port->pll);
+
+	debug("%s: pll_reg: 0x%p clk_id: %d\n", __func__, port->pll, clk_id);
+	/*
+	 * On the imx28 the values provided by CLKCTRL_PLL0* defines to are the
+	 * same as ones for CLKCTRL_PLL1*. As a result the former can be used
+	 * for both ports - i.e. (usb[01]).
+	 */
+	port->pll_en_bits = CLKCTRL_PLL0CTRL0_EN_USB_CLKS |
+		CLKCTRL_PLL0CTRL0_POWER;
+	port->pll_dis_bits = CLKCTRL_PLL0CTRL0_EN_USB_CLKS;
+	port->gate_bits = HW_DIGCTL_CTRL_USB0_CLKGATE;
+
+	return 0;
+}
+
+static int ehci_usb_probe(struct udevice *dev)
+{
+	struct usb_plat *plat = dev_get_plat(dev);
+	struct usb_ehci *ehci = dev_read_addr_ptr(dev);
+	struct ehci_mxs_priv_data *priv = dev_get_priv(dev);
+	struct ehci_mxs_port *port = &priv->port;
+	enum usb_init_type type = plat->init_type;
+	struct ehci_hccr *hccr;
+	struct ehci_hcor *hcor;
+	int ret;
+
+	priv->ehci = ehci;
+	priv->init_type = type;
+
+	debug("%s: USB type: %s  reg: 0x%x phy_reg 0x%p\n", __func__,
+	      type == USB_INIT_HOST ? "HOST" : "DEVICE", port->usb_regs,
+	      (uint32_t *)port->phy_regs);
+
+#if CONFIG_IS_ENABLED(DM_REGULATOR)
+	ret = device_get_supply_regulator(dev, "vbus-supply",
+					  &priv->vbus_supply);
+	if (ret)
+		debug("%s: No vbus supply\n", dev->name);
+
+	if (!ret && priv->vbus_supply) {
+		ret = regulator_set_enable(priv->vbus_supply,
+					   (type == USB_INIT_DEVICE) ?
+					   false : true);
+		if (ret) {
+			puts("Error enabling VBUS supply\n");
+			return ret;
+		}
+	}
+#endif
+	ret = __ehci_hcd_init(port, type, &hccr, &hcor);
+	if (ret)
+		return ret;
+
+	mdelay(10);
+	return ehci_register(dev, hccr, hcor, NULL, 0, priv->init_type);
+}
+
+static int ehci_usb_remove(struct udevice *dev)
+{
+	struct ehci_mxs_priv_data *priv = dev_get_priv(dev);
+	struct ehci_mxs_port *port = &priv->port;
+	int ret;
+
+	ret =  ehci_deregister(dev);
+	if (ret)
+		return ret;
+
+#if CONFIG_IS_ENABLED(DM_REGULATOR)
+	if (priv->vbus_supply) {
+		ret = regulator_set_enable(priv->vbus_supply, false);
+		if (ret) {
+			puts("Error disabling VBUS supply\n");
+			return ret;
+		}
+	}
+#endif
+	return __ehci_hcd_stop(port);
+}
+
+static const struct udevice_id mxs_usb_ids[] = {
+	{ .compatible = "fsl,imx28-usb" },
+	{ }
+};
+
+U_BOOT_DRIVER(usb_mxs) = {
+	.name	= "ehci_mxs",
+	.id	= UCLASS_USB,
+	.of_match = mxs_usb_ids,
+	.of_to_plat = ehci_usb_ofdata_to_platdata,
+	.probe	= ehci_usb_probe,
+	.remove = ehci_usb_remove,
+	.ops	= &ehci_usb_ops,
+	.plat_auto = sizeof(struct usb_plat),
+	.priv_auto = sizeof(struct ehci_mxs_priv_data),
+	.flags	= DM_FLAG_ALLOC_PRIV_DMA,
+};
+#endif /* !CONFIG_IS_ENABLED(DM_USB) */