linux/drivers/usb/phy/samsung-usbphy.c

/* linux/drivers/usb/phy/samsung-usbphy.c
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *              http://www.samsung.com
 *
 * Author: Praveen Paneri <p.paneri@samsung.com>
 *
 * Samsung USB2.0 PHY transceiver; talks to S3C HS OTG controller, EHCI-S5P and
 * OHCI-EXYNOS controllers.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/usb/otg.h>
#include <linux/usb/samsung_usb_phy.h>
#include <linux/platform_data/samsung-usbphy.h>

/* Register definitions */

#define SAMSUNG_PHYPWR				(0x00)

#define PHYPWR_NORMAL_MASK			(0x19 << 0)
#define PHYPWR_OTG_DISABLE			(0x1 << 4)
#define PHYPWR_ANALOG_POWERDOWN			(0x1 << 3)
#define PHYPWR_FORCE_SUSPEND			(0x1 << 1)
/* For Exynos4 */
#define PHYPWR_NORMAL_MASK_PHY0			(0x39 << 0)
#define PHYPWR_SLEEP_PHY0			(0x1 << 5)

#define SAMSUNG_PHYCLK				(0x04)

#define PHYCLK_MODE_USB11			(0x1 << 6)
#define PHYCLK_EXT_OSC				(0x1 << 5)
#define PHYCLK_COMMON_ON_N			(0x1 << 4)
#define PHYCLK_ID_PULL				(0x1 << 2)
#define PHYCLK_CLKSEL_MASK			(0x3 << 0)
#define PHYCLK_CLKSEL_48M			(0x0 << 0)
#define PHYCLK_CLKSEL_12M			(0x2 << 0)
#define PHYCLK_CLKSEL_24M			(0x3 << 0)

#define SAMSUNG_RSTCON				(0x08)

#define RSTCON_PHYLINK_SWRST			(0x1 << 2)
#define RSTCON_HLINK_SWRST			(0x1 << 1)
#define RSTCON_SWRST				(0x1 << 0)

/* EXYNOS5 */
#define EXYNOS5_PHY_HOST_CTRL0			(0x00)

#define HOST_CTRL0_PHYSWRSTALL			(0x1 << 31)

#define HOST_CTRL0_REFCLKSEL_MASK		(0x3 << 19)
#define HOST_CTRL0_REFCLKSEL_XTAL		(0x0 << 19)
#define HOST_CTRL0_REFCLKSEL_EXTL		(0x1 << 19)
#define HOST_CTRL0_REFCLKSEL_CLKCORE		(0x2 << 19)

#define HOST_CTRL0_FSEL_MASK			(0x7 << 16)
#define HOST_CTRL0_FSEL(_x)			((_x) << 16)

#define FSEL_CLKSEL_50M				(0x7)
#define FSEL_CLKSEL_24M				(0x5)
#define FSEL_CLKSEL_20M				(0x4)
#define FSEL_CLKSEL_19200K			(0x3)
#define FSEL_CLKSEL_12M				(0x2)
#define FSEL_CLKSEL_10M				(0x1)
#define FSEL_CLKSEL_9600K			(0x0)

#define HOST_CTRL0_TESTBURNIN			(0x1 << 11)
#define HOST_CTRL0_RETENABLE			(0x1 << 10)
#define HOST_CTRL0_COMMONON_N			(0x1 << 9)
#define HOST_CTRL0_SIDDQ			(0x1 << 6)
#define HOST_CTRL0_FORCESLEEP			(0x1 << 5)
#define HOST_CTRL0_FORCESUSPEND			(0x1 << 4)
#define HOST_CTRL0_WORDINTERFACE		(0x1 << 3)
#define HOST_CTRL0_UTMISWRST			(0x1 << 2)
#define HOST_CTRL0_LINKSWRST			(0x1 << 1)
#define HOST_CTRL0_PHYSWRST			(0x1 << 0)

#define EXYNOS5_PHY_HOST_TUNE0			(0x04)

#define EXYNOS5_PHY_HSIC_CTRL1			(0x10)

#define EXYNOS5_PHY_HSIC_TUNE1			(0x14)

#define EXYNOS5_PHY_HSIC_CTRL2			(0x20)

#define EXYNOS5_PHY_HSIC_TUNE2			(0x24)

#define HSIC_CTRL_REFCLKSEL_MASK		(0x3 << 23)
#define HSIC_CTRL_REFCLKSEL			(0x2 << 23)

#define HSIC_CTRL_REFCLKDIV_MASK		(0x7f << 16)
#define HSIC_CTRL_REFCLKDIV(_x)			((_x) << 16)
#define HSIC_CTRL_REFCLKDIV_12			(0x24 << 16)
#define HSIC_CTRL_REFCLKDIV_15			(0x1c << 16)
#define HSIC_CTRL_REFCLKDIV_16			(0x1a << 16)
#define HSIC_CTRL_REFCLKDIV_19_2		(0x15 << 16)
#define HSIC_CTRL_REFCLKDIV_20			(0x14 << 16)

#define HSIC_CTRL_SIDDQ				(0x1 << 6)
#define HSIC_CTRL_FORCESLEEP			(0x1 << 5)
#define HSIC_CTRL_FORCESUSPEND			(0x1 << 4)
#define HSIC_CTRL_WORDINTERFACE			(0x1 << 3)
#define HSIC_CTRL_UTMISWRST			(0x1 << 2)
#define HSIC_CTRL_PHYSWRST			(0x1 << 0)

#define EXYNOS5_PHY_HOST_EHCICTRL		(0x30)

#define HOST_EHCICTRL_ENAINCRXALIGN		(0x1 << 29)
#define HOST_EHCICTRL_ENAINCR4			(0x1 << 28)
#define HOST_EHCICTRL_ENAINCR8			(0x1 << 27)
#define HOST_EHCICTRL_ENAINCR16			(0x1 << 26)

#define EXYNOS5_PHY_HOST_OHCICTRL		(0x34)

#define HOST_OHCICTRL_SUSPLGCY			(0x1 << 3)
#define HOST_OHCICTRL_APPSTARTCLK		(0x1 << 2)
#define HOST_OHCICTRL_CNTSEL			(0x1 << 1)
#define HOST_OHCICTRL_CLKCKTRST			(0x1 << 0)

#define EXYNOS5_PHY_OTG_SYS			(0x38)

#define OTG_SYS_PHYLINK_SWRESET			(0x1 << 14)
#define OTG_SYS_LINKSWRST_UOTG			(0x1 << 13)
#define OTG_SYS_PHY0_SWRST			(0x1 << 12)

#define OTG_SYS_REFCLKSEL_MASK			(0x3 << 9)
#define OTG_SYS_REFCLKSEL_XTAL			(0x0 << 9)
#define OTG_SYS_REFCLKSEL_EXTL			(0x1 << 9)
#define OTG_SYS_REFCLKSEL_CLKCORE		(0x2 << 9)

#define OTG_SYS_IDPULLUP_UOTG			(0x1 << 8)
#define OTG_SYS_COMMON_ON			(0x1 << 7)

#define OTG_SYS_FSEL_MASK			(0x7 << 4)
#define OTG_SYS_FSEL(_x)			((_x) << 4)

#define OTG_SYS_FORCESLEEP			(0x1 << 3)
#define OTG_SYS_OTGDISABLE			(0x1 << 2)
#define OTG_SYS_SIDDQ_UOTG			(0x1 << 1)
#define OTG_SYS_FORCESUSPEND			(0x1 << 0)

#define EXYNOS5_PHY_OTG_TUNE			(0x40)

#ifndef MHZ
#define MHZ (1000*1000)
#endif

#ifndef KHZ
#define KHZ (1000)
#endif

#define EXYNOS_USBHOST_PHY_CTRL_OFFSET		(0x4)
#define S3C64XX_USBPHY_ENABLE			(0x1 << 16)
#define EXYNOS_USBPHY_ENABLE			(0x1 << 0)
#define EXYNOS_USB20PHY_CFG_HOST_LINK		(0x1 << 0)

enum samsung_cpu_type {
	TYPE_S3C64XX,
	TYPE_EXYNOS4210,
	TYPE_EXYNOS5250,
};

/*
 * struct samsung_usbphy_drvdata - driver data for various SoC variants
 * @cpu_type: machine identifier
 * @devphy_en_mask: device phy enable mask for PHY CONTROL register
 * @hostphy_en_mask: host phy enable mask for PHY CONTROL register
 * @devphy_reg_offset: offset to DEVICE PHY CONTROL register from
 *		       mapped address of system controller.
 * @hostphy_reg_offset: offset to HOST PHY CONTROL register from
 *		       mapped address of system controller.
 *
 *	Here we have a separate mask for device type phy.
 *	Having different masks for host and device type phy helps
 *	in setting independent masks in case of SoCs like S5PV210,
 *	in which PHY0 and PHY1 enable bits belong to same register
 *	placed at position 0 and 1 respectively.
 *	Although for newer SoCs like exynos these bits belong to
 *	different registers altogether placed at position 0.
 */
struct samsung_usbphy_drvdata {
	int cpu_type;
	int devphy_en_mask;
	int hostphy_en_mask;
	u32 devphy_reg_offset;
	u32 hostphy_reg_offset;
};

/*
 * struct samsung_usbphy - transceiver driver state
 * @phy: transceiver structure
 * @plat: platform data
 * @dev: The parent device supplied to the probe function
 * @clk: usb phy clock
 * @regs: usb phy controller registers memory base
 * @pmuregs: USB device PHY_CONTROL register memory base
 * @sysreg: USB2.0 PHY_CFG register memory base
 * @ref_clk_freq: reference clock frequency selection
 * @drv_data: driver data available for different SoCs
 * @phy_type: Samsung SoCs specific phy types:	#HOST
 *						#DEVICE
 * @phy_usage: usage count for phy
 * @lock: lock for phy operations
 */
struct samsung_usbphy {
	struct usb_phy	phy;
	struct samsung_usbphy_data *plat;
	struct device	*dev;
	struct clk	*clk;
	void __iomem	*regs;
	void __iomem	*pmuregs;
	void __iomem	*sysreg;
	int		ref_clk_freq;
	const struct samsung_usbphy_drvdata *drv_data;
	enum samsung_usb_phy_type phy_type;
	atomic_t	phy_usage;
	spinlock_t	lock;
};

#define phy_to_sphy(x)		container_of((x), struct samsung_usbphy, phy)

int samsung_usbphy_set_host(struct usb_otg *otg, struct usb_bus *host)
{
	if (!otg)
		return -ENODEV;

	if (!otg->host)
		otg->host = host;

	return 0;
}

static int samsung_usbphy_parse_dt(struct samsung_usbphy *sphy)
{
	struct device_node *usbphy_sys;

	/* Getting node for system controller interface for usb-phy */
	usbphy_sys = of_get_child_by_name(sphy->dev->of_node, "usbphy-sys");
	if (!usbphy_sys) {
		dev_err(sphy->dev, "No sys-controller interface for usb-phy\n");
		return -ENODEV;
	}

	sphy->pmuregs = of_iomap(usbphy_sys, 0);

	if (sphy->pmuregs == NULL) {
		dev_err(sphy->dev, "Can't get usb-phy pmu control register\n");
		goto err0;
	}

	sphy->sysreg = of_iomap(usbphy_sys, 1);

	/*
	 * Not returning error code here, since this situation is not fatal.
	 * Few SoCs may not have this switch available
	 */
	if (sphy->sysreg == NULL)
		dev_warn(sphy->dev, "Can't get usb-phy sysreg cfg register\n");

	of_node_put(usbphy_sys);

	return 0;

err0:
	of_node_put(usbphy_sys);
	return -ENXIO;
}

/*
 * Set isolation here for phy.
 * Here 'on = true' would mean USB PHY block is isolated, hence
 * de-activated and vice-versa.
 */
static void samsung_usbphy_set_isolation(struct samsung_usbphy *sphy, bool on)
{
	void __iomem *reg = NULL;
	u32 reg_val;
	u32 en_mask = 0;

	if (!sphy->pmuregs) {
		dev_warn(sphy->dev, "Can't set pmu isolation\n");
		return;
	}

	switch (sphy->drv_data->cpu_type) {
	case TYPE_S3C64XX:
		/*
		 * Do nothing: We will add here once S3C64xx goes for DT support
		 */
		break;
	case TYPE_EXYNOS4210:
		/*
		 * Fall through since exynos4210 and exynos5250 have similar
		 * register architecture: two separate registers for host and
		 * device phy control with enable bit at position 0.
		 */
	case TYPE_EXYNOS5250:
		if (sphy->phy_type == USB_PHY_TYPE_DEVICE) {
			reg = sphy->pmuregs +
				sphy->drv_data->devphy_reg_offset;
			en_mask = sphy->drv_data->devphy_en_mask;
		} else if (sphy->phy_type == USB_PHY_TYPE_HOST) {
			reg = sphy->pmuregs +
				sphy->drv_data->hostphy_reg_offset;
			en_mask = sphy->drv_data->hostphy_en_mask;
		}
		break;
	default:
		dev_err(sphy->dev, "Invalid SoC type\n");
		return;
	}

	reg_val = readl(reg);

	if (on)
		reg_val &= ~en_mask;
	else
		reg_val |= en_mask;

	writel(reg_val, reg);
}

/*
 * Configure the mode of working of usb-phy here: HOST/DEVICE.
 */
static void samsung_usbphy_cfg_sel(struct samsung_usbphy *sphy)
{
	u32 reg;

	if (!sphy->sysreg) {
		dev_warn(sphy->dev, "Can't configure specified phy mode\n");
		return;
	}

	reg = readl(sphy->sysreg);

	if (sphy->phy_type == USB_PHY_TYPE_DEVICE)
		reg &= ~EXYNOS_USB20PHY_CFG_HOST_LINK;
	else if (sphy->phy_type == USB_PHY_TYPE_HOST)
		reg |= EXYNOS_USB20PHY_CFG_HOST_LINK;

	writel(reg, sphy->sysreg);
}

/*
 * PHYs are different for USB Device and USB Host.
 * This make sure that correct PHY type is selected before
 * any operation on PHY.
 */
static int samsung_usbphy_set_type(struct usb_phy *phy,
				enum samsung_usb_phy_type phy_type)
{
	struct samsung_usbphy *sphy = phy_to_sphy(phy);

	sphy->phy_type = phy_type;

	return 0;
}

/*
 * Returns reference clock frequency selection value
 */
static int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy)
{
	struct clk *ref_clk;
	int refclk_freq = 0;

	/*
	 * In exynos5250 USB host and device PHY use
	 * external crystal clock XXTI
	 */
	if (sphy->drv_data->cpu_type == TYPE_EXYNOS5250)
		ref_clk = clk_get(sphy->dev, "ext_xtal");
	else
		ref_clk = clk_get(sphy->dev, "xusbxti");
	if (IS_ERR(ref_clk)) {
		dev_err(sphy->dev, "Failed to get reference clock\n");
		return PTR_ERR(ref_clk);
	}

	if (sphy->drv_data->cpu_type == TYPE_EXYNOS5250) {
		/* set clock frequency for PLL */
		switch (clk_get_rate(ref_clk)) {
		case 9600 * KHZ:
			refclk_freq = FSEL_CLKSEL_9600K;
			break;
		case 10 * MHZ:
			refclk_freq = FSEL_CLKSEL_10M;
			break;
		case 12 * MHZ:
			refclk_freq = FSEL_CLKSEL_12M;
			break;
		case 19200 * KHZ:
			refclk_freq = FSEL_CLKSEL_19200K;
			break;
		case 20 * MHZ:
			refclk_freq = FSEL_CLKSEL_20M;
			break;
		case 50 * MHZ:
			refclk_freq = FSEL_CLKSEL_50M;
			break;
		case 24 * MHZ:
		default:
			/* default reference clock */
			refclk_freq = FSEL_CLKSEL_24M;
			break;
		}
	} else {
		switch (clk_get_rate(ref_clk)) {
		case 12 * MHZ:
			refclk_freq = PHYCLK_CLKSEL_12M;
			break;
		case 24 * MHZ:
			refclk_freq = PHYCLK_CLKSEL_24M;
			break;
		case 48 * MHZ:
			refclk_freq = PHYCLK_CLKSEL_48M;
			break;
		default:
			if (sphy->drv_data->cpu_type == TYPE_S3C64XX)
				refclk_freq = PHYCLK_CLKSEL_48M;
			else
				refclk_freq = PHYCLK_CLKSEL_24M;
			break;
		}
	}
	clk_put(ref_clk);

	return refclk_freq;
}

static bool exynos5_phyhost_is_on(void *regs)
{
	u32 reg;

	reg = readl(regs + EXYNOS5_PHY_HOST_CTRL0);

	return !(reg & HOST_CTRL0_SIDDQ);
}

static void samsung_exynos5_usbphy_enable(struct samsung_usbphy *sphy)
{
	void __iomem *regs = sphy->regs;
	u32 phyclk = sphy->ref_clk_freq;
	u32 phyhost;
	u32 phyotg;
	u32 phyhsic;
	u32 ehcictrl;
	u32 ohcictrl;

	/*
	 * phy_usage helps in keeping usage count for phy
	 * so that the first consumer enabling the phy is also
	 * the last consumer to disable it.
	 */

	atomic_inc(&sphy->phy_usage);

	if (exynos5_phyhost_is_on(regs)) {
		dev_info(sphy->dev, "Already power on PHY\n");
		return;
	}

	/* Host configuration */
	phyhost = readl(regs + EXYNOS5_PHY_HOST_CTRL0);

	/* phy reference clock configuration */
	phyhost &= ~HOST_CTRL0_FSEL_MASK;
	phyhost |= HOST_CTRL0_FSEL(phyclk);

	/* host phy reset */
	phyhost &= ~(HOST_CTRL0_PHYSWRST |
			HOST_CTRL0_PHYSWRSTALL |
			HOST_CTRL0_SIDDQ |
			/* Enable normal mode of operation */
			HOST_CTRL0_FORCESUSPEND |
			HOST_CTRL0_FORCESLEEP);

	/* Link reset */
	phyhost |= (HOST_CTRL0_LINKSWRST |
			HOST_CTRL0_UTMISWRST |
			/* COMMON Block configuration during suspend */
			HOST_CTRL0_COMMONON_N);
	writel(phyhost, regs + EXYNOS5_PHY_HOST_CTRL0);
	udelay(10);
	phyhost &= ~(HOST_CTRL0_LINKSWRST |
			HOST_CTRL0_UTMISWRST);
	writel(phyhost, regs + EXYNOS5_PHY_HOST_CTRL0);

	/* OTG configuration */
	phyotg = readl(regs + EXYNOS5_PHY_OTG_SYS);

	/* phy reference clock configuration */
	phyotg &= ~OTG_SYS_FSEL_MASK;
	phyotg |= OTG_SYS_FSEL(phyclk);

	/* Enable normal mode of operation */
	phyotg &= ~(OTG_SYS_FORCESUSPEND |
			OTG_SYS_SIDDQ_UOTG |
			OTG_SYS_FORCESLEEP |
			OTG_SYS_REFCLKSEL_MASK |
			/* COMMON Block configuration during suspend */
			OTG_SYS_COMMON_ON);

	/* OTG phy & link reset */
	phyotg |= (OTG_SYS_PHY0_SWRST |
			OTG_SYS_LINKSWRST_UOTG |
			OTG_SYS_PHYLINK_SWRESET |
			OTG_SYS_OTGDISABLE |
			/* Set phy refclk */
			OTG_SYS_REFCLKSEL_CLKCORE);

	writel(phyotg, regs + EXYNOS5_PHY_OTG_SYS);
	udelay(10);
	phyotg &= ~(OTG_SYS_PHY0_SWRST |
			OTG_SYS_LINKSWRST_UOTG |
			OTG_SYS_PHYLINK_SWRESET);
	writel(phyotg, regs + EXYNOS5_PHY_OTG_SYS);

	/* HSIC phy configuration */
	phyhsic = (HSIC_CTRL_REFCLKDIV_12 |
			HSIC_CTRL_REFCLKSEL |
			HSIC_CTRL_PHYSWRST);
	writel(phyhsic, regs + EXYNOS5_PHY_HSIC_CTRL1);
	writel(phyhsic, regs + EXYNOS5_PHY_HSIC_CTRL2);
	udelay(10);
	phyhsic &= ~HSIC_CTRL_PHYSWRST;
	writel(phyhsic, regs + EXYNOS5_PHY_HSIC_CTRL1);
	writel(phyhsic, regs + EXYNOS5_PHY_HSIC_CTRL2);

	udelay(80);

	/* enable EHCI DMA burst */
	ehcictrl = readl(regs + EXYNOS5_PHY_HOST_EHCICTRL);
	ehcictrl |= (HOST_EHCICTRL_ENAINCRXALIGN |
				HOST_EHCICTRL_ENAINCR4 |
				HOST_EHCICTRL_ENAINCR8 |
				HOST_EHCICTRL_ENAINCR16);
	writel(ehcictrl, regs + EXYNOS5_PHY_HOST_EHCICTRL);

	/* set ohci_suspend_on_n */
	ohcictrl = readl(regs + EXYNOS5_PHY_HOST_OHCICTRL);
	ohcictrl |= HOST_OHCICTRL_SUSPLGCY;
	writel(ohcictrl, regs + EXYNOS5_PHY_HOST_OHCICTRL);
}

static void samsung_usbphy_enable(struct samsung_usbphy *sphy)
{
	void __iomem *regs = sphy->regs;
	u32 phypwr;
	u32 phyclk;
	u32 rstcon;

	/* set clock frequency for PLL */
	phyclk = sphy->ref_clk_freq;
	phypwr = readl(regs + SAMSUNG_PHYPWR);
	rstcon = readl(regs + SAMSUNG_RSTCON);

	switch (sphy->drv_data->cpu_type) {
	case TYPE_S3C64XX:
		phyclk &= ~PHYCLK_COMMON_ON_N;
		phypwr &= ~PHYPWR_NORMAL_MASK;
		rstcon |= RSTCON_SWRST;
		break;
	case TYPE_EXYNOS4210:
		phypwr &= ~PHYPWR_NORMAL_MASK_PHY0;
		rstcon |= RSTCON_SWRST;
	default:
		break;
	}

	writel(phyclk, regs + SAMSUNG_PHYCLK);
	/* Configure PHY0 for normal operation*/
	writel(phypwr, regs + SAMSUNG_PHYPWR);
	/* reset all ports of PHY and Link */
	writel(rstcon, regs + SAMSUNG_RSTCON);
	udelay(10);
	rstcon &= ~RSTCON_SWRST;
	writel(rstcon, regs + SAMSUNG_RSTCON);
}

static void samsung_exynos5_usbphy_disable(struct samsung_usbphy *sphy)
{
	void __iomem *regs = sphy->regs;
	u32 phyhost;
	u32 phyotg;
	u32 phyhsic;

	if (atomic_dec_return(&sphy->phy_usage) > 0) {
		dev_info(sphy->dev, "still being used\n");
		return;
	}

	phyhsic = (HSIC_CTRL_REFCLKDIV_12 |
			HSIC_CTRL_REFCLKSEL |
			HSIC_CTRL_SIDDQ |
			HSIC_CTRL_FORCESLEEP |
			HSIC_CTRL_FORCESUSPEND);
	writel(phyhsic, regs + EXYNOS5_PHY_HSIC_CTRL1);
	writel(phyhsic, regs + EXYNOS5_PHY_HSIC_CTRL2);

	phyhost = readl(regs + EXYNOS5_PHY_HOST_CTRL0);
	phyhost |= (HOST_CTRL0_SIDDQ |
			HOST_CTRL0_FORCESUSPEND |
			HOST_CTRL0_FORCESLEEP |
			HOST_CTRL0_PHYSWRST |
			HOST_CTRL0_PHYSWRSTALL);
	writel(phyhost, regs + EXYNOS5_PHY_HOST_CTRL0);

	phyotg = readl(regs + EXYNOS5_PHY_OTG_SYS);
	phyotg |= (OTG_SYS_FORCESUSPEND |
			OTG_SYS_SIDDQ_UOTG |
			OTG_SYS_FORCESLEEP);
	writel(phyotg, regs + EXYNOS5_PHY_OTG_SYS);
}

static void samsung_usbphy_disable(struct samsung_usbphy *sphy)
{
	void __iomem *regs = sphy->regs;
	u32 phypwr;

	phypwr = readl(regs + SAMSUNG_PHYPWR);

	switch (sphy->drv_data->cpu_type) {
	case TYPE_S3C64XX:
		phypwr |= PHYPWR_NORMAL_MASK;
		break;
	case TYPE_EXYNOS4210:
		phypwr |= PHYPWR_NORMAL_MASK_PHY0;
	default:
		break;
	}

	/* Disable analog and otg block power */
	writel(phypwr, regs + SAMSUNG_PHYPWR);
}

/*
 * The function passed to the usb driver for phy initialization
 */
static int samsung_usbphy_init(struct usb_phy *phy)
{
	struct samsung_usbphy *sphy;
	struct usb_bus *host = NULL;
	unsigned long flags;
	int ret = 0;

	sphy = phy_to_sphy(phy);

	host = phy->otg->host;

	/* Enable the phy clock */
	ret = clk_prepare_enable(sphy->clk);
	if (ret) {
		dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
		return ret;
	}

	spin_lock_irqsave(&sphy->lock, flags);

	if (host) {
		/* setting default phy-type for USB 2.0 */
		if (!strstr(dev_name(host->controller), "ehci") ||
				!strstr(dev_name(host->controller), "ohci"))
			samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_HOST);
	} else {
		samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_DEVICE);
	}

	/* Disable phy isolation */
	if (sphy->plat && sphy->plat->pmu_isolation)
		sphy->plat->pmu_isolation(false);
	else
		samsung_usbphy_set_isolation(sphy, false);

	/* Selecting Host/OTG mode; After reset USB2.0PHY_CFG: HOST */
	samsung_usbphy_cfg_sel(sphy);

	/* Initialize usb phy registers */
	if (sphy->drv_data->cpu_type == TYPE_EXYNOS5250)
		samsung_exynos5_usbphy_enable(sphy);
	else
		samsung_usbphy_enable(sphy);

	spin_unlock_irqrestore(&sphy->lock, flags);

	/* Disable the phy clock */
	clk_disable_unprepare(sphy->clk);

	return ret;
}

/*
 * The function passed to the usb driver for phy shutdown
 */
static void samsung_usbphy_shutdown(struct usb_phy *phy)
{
	struct samsung_usbphy *sphy;
	struct usb_bus *host = NULL;
	unsigned long flags;

	sphy = phy_to_sphy(phy);

	host = phy->otg->host;

	if (clk_prepare_enable(sphy->clk)) {
		dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
		return;
	}

	spin_lock_irqsave(&sphy->lock, flags);

	if (host) {
		/* setting default phy-type for USB 2.0 */
		if (!strstr(dev_name(host->controller), "ehci") ||
				!strstr(dev_name(host->controller), "ohci"))
			samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_HOST);
	} else {
		samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_DEVICE);
	}

	/* De-initialize usb phy registers */
	if (sphy->drv_data->cpu_type == TYPE_EXYNOS5250)
		samsung_exynos5_usbphy_disable(sphy);
	else
		samsung_usbphy_disable(sphy);

	/* Enable phy isolation */
	if (sphy->plat && sphy->plat->pmu_isolation)
		sphy->plat->pmu_isolation(true);
	else
		samsung_usbphy_set_isolation(sphy, true);

	spin_unlock_irqrestore(&sphy->lock, flags);

	clk_disable_unprepare(sphy->clk);
}

static const struct of_device_id samsung_usbphy_dt_match[];

static inline const struct samsung_usbphy_drvdata
*samsung_usbphy_get_driver_data(struct platform_device *pdev)
{
	if (pdev->dev.of_node) {
		const struct of_device_id *match;
		match = of_match_node(samsung_usbphy_dt_match,
							pdev->dev.of_node);
		return match->data;
	}

	return (struct samsung_usbphy_drvdata *)
				platform_get_device_id(pdev)->driver_data;
}

static int samsung_usbphy_probe(struct platform_device *pdev)
{
	struct samsung_usbphy *sphy;
	struct usb_otg *otg;
	struct samsung_usbphy_data *pdata = pdev->dev.platform_data;
	const struct samsung_usbphy_drvdata *drv_data;
	struct device *dev = &pdev->dev;
	struct resource *phy_mem;
	void __iomem	*phy_base;
	struct clk *clk;
	int ret;

	phy_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!phy_mem) {
		dev_err(dev, "%s: missing mem resource\n", __func__);
		return -ENODEV;
	}

	phy_base = devm_ioremap_resource(dev, phy_mem);
	if (IS_ERR(phy_base))
		return PTR_ERR(phy_base);

	sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
	if (!sphy)
		return -ENOMEM;

	otg = devm_kzalloc(dev, sizeof(*otg), GFP_KERNEL);
	if (!otg)
		return -ENOMEM;

	drv_data = samsung_usbphy_get_driver_data(pdev);

	if (drv_data->cpu_type == TYPE_EXYNOS5250)
		clk = devm_clk_get(dev, "usbhost");
	else
		clk = devm_clk_get(dev, "otg");

	if (IS_ERR(clk)) {
		dev_err(dev, "Failed to get otg clock\n");
		return PTR_ERR(clk);
	}

	sphy->dev = dev;

	if (dev->of_node) {
		ret = samsung_usbphy_parse_dt(sphy);
		if (ret < 0)
			return ret;
	} else {
		if (!pdata) {
			dev_err(dev, "no platform data specified\n");
			return -EINVAL;
		}
	}

	sphy->plat		= pdata;
	sphy->regs		= phy_base;
	sphy->clk		= clk;
	sphy->drv_data		= drv_data;
	sphy->phy.dev		= sphy->dev;
	sphy->phy.label		= "samsung-usbphy";
	sphy->phy.init		= samsung_usbphy_init;
	sphy->phy.shutdown	= samsung_usbphy_shutdown;
	sphy->ref_clk_freq	= samsung_usbphy_get_refclk_freq(sphy);

	sphy->phy.otg		= otg;
	sphy->phy.otg->phy	= &sphy->phy;
	sphy->phy.otg->set_host = samsung_usbphy_set_host;

	spin_lock_init(&sphy->lock);

	platform_set_drvdata(pdev, sphy);

	return usb_add_phy(&sphy->phy, USB_PHY_TYPE_USB2);
}

static int samsung_usbphy_remove(struct platform_device *pdev)
{
	struct samsung_usbphy *sphy = platform_get_drvdata(pdev);

	usb_remove_phy(&sphy->phy);

	if (sphy->pmuregs)
		iounmap(sphy->pmuregs);
	if (sphy->sysreg)
		iounmap(sphy->sysreg);

	return 0;
}

static const struct samsung_usbphy_drvdata usbphy_s3c64xx = {
	.cpu_type		= TYPE_S3C64XX,
	.devphy_en_mask		= S3C64XX_USBPHY_ENABLE,
};

static const struct samsung_usbphy_drvdata usbphy_exynos4 = {
	.cpu_type		= TYPE_EXYNOS4210,
	.devphy_en_mask		= EXYNOS_USBPHY_ENABLE,
	.hostphy_en_mask	= EXYNOS_USBPHY_ENABLE,
};

static struct samsung_usbphy_drvdata usbphy_exynos5 = {
	.cpu_type		= TYPE_EXYNOS5250,
	.hostphy_en_mask	= EXYNOS_USBPHY_ENABLE,
	.hostphy_reg_offset	= EXYNOS_USBHOST_PHY_CTRL_OFFSET,
};

#ifdef CONFIG_OF
static const struct of_device_id samsung_usbphy_dt_match[] = {
	{
		.compatible = "samsung,s3c64xx-usbphy",
		.data = &usbphy_s3c64xx,
	}, {
		.compatible = "samsung,exynos4210-usbphy",
		.data = &usbphy_exynos4,
	}, {
		.compatible = "samsung,exynos5250-usbphy",
		.data = &usbphy_exynos5
	},
	{},
};
MODULE_DEVICE_TABLE(of, samsung_usbphy_dt_match);
#endif

static struct platform_device_id samsung_usbphy_driver_ids[] = {
	{
		.name		= "s3c64xx-usbphy",
		.driver_data	= (unsigned long)&usbphy_s3c64xx,
	}, {
		.name		= "exynos4210-usbphy",
		.driver_data	= (unsigned long)&usbphy_exynos4,
	}, {
		.name		= "exynos5250-usbphy",
		.driver_data	= (unsigned long)&usbphy_exynos5,
	},
	{},
};

MODULE_DEVICE_TABLE(platform, samsung_usbphy_driver_ids);

static struct platform_driver samsung_usbphy_driver = {
	.probe		= samsung_usbphy_probe,
	.remove		= samsung_usbphy_remove,
	.id_table	= samsung_usbphy_driver_ids,
	.driver		= {
		.name	= "samsung-usbphy",
		.owner	= THIS_MODULE,
		.of_match_table = of_match_ptr(samsung_usbphy_dt_match),
	},
};

module_platform_driver(samsung_usbphy_driver);

MODULE_DESCRIPTION("Samsung USB phy controller");
MODULE_AUTHOR("Praveen Paneri <p.paneri@samsung.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:samsung-usbphy");