phy: db410c: Add MSM USB PHY driver

Add a PHY driver for the Qualcomm dragonboard 410c which
allows switching on/off and resetting the phy connected
to the EHCI controllers and USBHS controller.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>

MAINTAINERS

@@ -210,6 +210,7 @@ S:	Maintained
 F:	arch/arm/mach-snapdragon/
 F:	drivers/gpio/msm_gpio.c
 F:	drivers/mmc/msm_sdhci.c
+F:	drivers/phy/msm8916-usbh-phy.c
 F:	drivers/serial/serial_msm.c
 F:	drivers/smem/msm_smem.c
 F:	drivers/usb/host/ehci-msm.c

drivers/phy/Kconfig

@@ -139,4 +139,12 @@ config MESON_GXL_USB_PHY
 	  This is the generic phy driver for the Amlogic Meson GXL
 	  USB2 and USB3 PHYS.
 
+config MSM8916_USB_PHY
+	bool "Qualcomm MSM8916 USB PHY support"
+	depends on PHY
+	help
+          Support the USB PHY in msm8916
+
+	  This PHY is found on qualcomm dragonboard410c development board.
+
 endmenu

drivers/phy/Makefile

@@ -15,3 +15,4 @@ obj-$(CONFIG_STI_USB_PHY) += sti_usb_phy.o
 obj-$(CONFIG_PHY_RCAR_GEN2) += phy-rcar-gen2.o
 obj-$(CONFIG_PHY_STM32_USBPHYC) += phy-stm32-usbphyc.o
 obj-$(CONFIG_MESON_GXL_USB_PHY) += meson-gxl-usb2.o meson-gxl-usb3.o
+obj-$(CONFIG_MSM8916_USB_PHY) += msm8916-usbh-phy.o

drivers/phy/msm8916-usbh-phy.c

@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Ramon Fried <ramon.fried@gmail.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <generic-phy.h>
+#include <usb/ehci-ci.h>
+#include <usb/ulpi.h>
+#include <asm/io.h>
+
+/* PHY viewport regs */
+#define ULPI_MISC_A_READ		0x96
+#define ULPI_MISC_A_SET			0x97
+#define ULPI_MISC_A_CLEAR		0x98
+#define ULPI_MISC_A_VBUSVLDEXT		BIT(0)
+#define ULPI_MISC_A_VBUSVLDEXTSEL	BIT(1)
+#define GEN2_SESS_VLD_CTRL_EN		BIT(7)
+#define SESS_VLD_CTRL			BIT(25)
+
+struct msm_phy_priv {
+	void __iomem *regs;
+	struct usb_ehci *ehci; /* Start of IP core*/
+	struct ulpi_viewport ulpi_vp; /* ULPI Viewport */
+};
+
+static int msm_phy_power_on(struct phy *phy)
+{
+	struct msm_phy_priv *priv = dev_get_priv(phy->dev);
+
+	/* Select and enable external configuration with USB PHY */
+	ulpi_write(&priv->ulpi_vp, (u8 *)ULPI_MISC_A_SET,
+		   ULPI_MISC_A_VBUSVLDEXTSEL | ULPI_MISC_A_VBUSVLDEXT);
+
+	return 0;
+}
+
+static int msm_phy_power_off(struct phy *phy)
+{
+	struct msm_phy_priv *priv = dev_get_priv(phy->dev);
+
+	/* Disable VBUS mimicing in the controller. */
+	ulpi_write(&priv->ulpi_vp, (u8 *)ULPI_MISC_A_CLEAR,
+		   ULPI_MISC_A_VBUSVLDEXTSEL | ULPI_MISC_A_VBUSVLDEXT);
+	return 0;
+}
+
+static int msm_phy_reset(struct phy *phy)
+{
+	struct msm_phy_priv *p = dev_get_priv(phy->dev);
+
+	/* select ULPI phy */
+	writel(PORT_PTS_ULPI, &p->ehci->portsc);
+
+	/* Enable sess_vld */
+	setbits_le32(&p->ehci->genconfig2, GEN2_SESS_VLD_CTRL_EN);
+
+	/* Enable external vbus configuration in the LINK */
+	setbits_le32(&p->ehci->usbcmd, SESS_VLD_CTRL);
+
+	/* USB_OTG_HS_AHB_BURST */
+	writel(0x0, &p->ehci->sbuscfg);
+
+	/* USB_OTG_HS_AHB_MODE: HPROT_MODE */
+	/* Bus access related config. */
+	writel(0x08, &p->ehci->sbusmode);
+
+	return 0;
+}
+
+static int msm_phy_probe(struct udevice *dev)
+{
+	struct msm_phy_priv *priv = dev_get_priv(dev);
+
+	priv->regs = dev_remap_addr(dev);
+	if (!priv->regs)
+		return -EINVAL;
+
+	priv->ehci = (struct usb_ehci *)priv->regs;
+	priv->ulpi_vp.port_num = 0;
+
+	/* Warning: this will not work if viewport address is > 64 bit due to
+	 * ULPI design.
+	 */
+	priv->ulpi_vp.viewport_addr = (phys_addr_t)&priv->ehci->ulpi_viewpoint;
+
+	return 0;
+}
+
+static struct phy_ops msm_phy_ops = {
+	.power_on = msm_phy_power_on,
+	.power_off = msm_phy_power_off,
+	.reset = msm_phy_reset,
+};
+
+static const struct udevice_id msm_phy_ids[] = {
+	{ .compatible = "qcom,apq8016-usbphy" },
+	{ }
+};
+
+U_BOOT_DRIVER(msm8916_usbphy) = {
+	.name		= "msm8916_usbphy",
+	.id		= UCLASS_PHY,
+	.of_match	= msm_phy_ids,
+	.ops		= &msm_phy_ops,
+	.probe		= msm_phy_probe,
+	.priv_auto_alloc_size = sizeof(struct msm_phy_priv),
+};