phy: Add support for phy-da8xx-usb

In preparation for supporting the musb driver, this patch
adds support for the usb phy associated with the musb driver.

Signed-off-by: Adam Ford <aford173@gmail.com>

drivers/phy/Kconfig

@@ -84,6 +84,12 @@ config BCM6368_USBH_PHY
 	help
 	  Support for the Broadcom MIPS BCM6368 USBH PHY.
 
+config PHY_DA8XX_USB
+	tristate "TI DA8xx USB PHY Driver"
+	depends on PHY && ARCH_DAVINCI
+	help
+	  Enable this to support the USB PHY on DA8xx SoCs.
+
 config PIPE3_PHY
 	bool "Support omap's PIPE3 PHY"
 	depends on PHY && ARCH_OMAP2PLUS

drivers/phy/Makefile

@@ -21,3 +21,4 @@ obj-$(CONFIG_MSM8916_USB_PHY) += msm8916-usbh-phy.o
 obj-$(CONFIG_OMAP_USB2_PHY) += omap-usb2-phy.o
 obj-$(CONFIG_KEYSTONE_USB_PHY) += keystone-usb-phy.o
 obj-$(CONFIG_MT76X8_USB_PHY) += mt76x8-usb-phy.o
+obj-$(CONFIG_PHY_DA8XX_USB) += phy-da8xx-usb.o

drivers/phy/phy-da8xx-usb.c

@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Based on the DA8xx "glue layer" code.
+ * Copyright (c) 2008-2019, MontaVista Software, Inc. <source@mvista.com>
+ *
+ * DT support added by: Adam Ford <aford173@gmail.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/device-internal.h>
+#include <dm/lists.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/da8xx-usb.h>
+#include <asm/io.h>
+#include <generic-phy.h>
+
+static int da8xx_usb_phy_power_on(struct phy *phy)
+{
+	unsigned long timeout;
+
+	clrsetbits_le32(&davinci_syscfg_regs->cfgchip2,
+			CFGCHIP2_RESET | CFGCHIP2_PHYPWRDN | CFGCHIP2_OTGPWRDN |
+			CFGCHIP2_OTGMODE | CFGCHIP2_REFFREQ,
+			CFGCHIP2_SESENDEN | CFGCHIP2_VBDTCTEN |
+			CFGCHIP2_PHY_PLLON | CFGCHIP2_REFFREQ_24MHZ);
+
+	/* wait until the usb phy pll locks */
+	timeout = get_timer(0);
+	while (get_timer(timeout) < 10) {
+		if (readl(&davinci_syscfg_regs->cfgchip2) & CFGCHIP2_PHYCLKGD)
+			return 0;
+	}
+
+	debug("Phy was not turned on\n");
+
+	return -ENODEV;
+}
+
+static int da8xx_usb_phy_power_off(struct phy *phy)
+{
+	clrsetbits_le32(&davinci_syscfg_regs->cfgchip2,
+			CFGCHIP2_PHY_PLLON,
+			CFGCHIP2_PHYPWRDN | CFGCHIP2_OTGPWRDN);
+
+	return 0;
+}
+
+static const struct udevice_id da8xx_phy_ids[] = {
+	{ .compatible = "ti,da830-usb-phy" },
+	{ }
+};
+
+static struct phy_ops da8xx_phy_ops = {
+	.power_on = da8xx_usb_phy_power_on,
+	.power_off = da8xx_usb_phy_power_off,
+};
+
+U_BOOT_DRIVER(da8xx_phy) = {
+	.name	= "da8xx-usb-phy",
+	.id	= UCLASS_PHY,
+	.of_match = da8xx_phy_ids,
+	.ops = &da8xx_phy_ops,
+};