drivers/usb/phy/phy-tegra-usb.c

/*
 * Copyright (C) 2010 Google, Inc.
 *
 * Author:
 *	Erik Gilling <konkers@google.com>
 *	Benoit Goby <benoit@android.com>
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * 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/resource.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/usb/otg.h>
#include <linux/usb/ulpi.h>
#include <asm/mach-types.h>
#include <linux/usb/tegra_usb_phy.h>

#define TEGRA_USB_BASE		0xC5000000
#define TEGRA_USB_SIZE		SZ_16K

#define ULPI_VIEWPORT		0x170

#define USB_SUSP_CTRL		0x400
#define   USB_WAKE_ON_CNNT_EN_DEV	(1 << 3)
#define   USB_WAKE_ON_DISCON_EN_DEV	(1 << 4)
#define   USB_SUSP_CLR		(1 << 5)
#define   USB_PHY_CLK_VALID	(1 << 7)
#define   UTMIP_RESET			(1 << 11)
#define   UHSIC_RESET			(1 << 11)
#define   UTMIP_PHY_ENABLE		(1 << 12)
#define   ULPI_PHY_ENABLE	(1 << 13)
#define   USB_SUSP_SET		(1 << 14)
#define   USB_WAKEUP_DEBOUNCE_COUNT(x)	(((x) & 0x7) << 16)

#define USB1_LEGACY_CTRL	0x410
#define   USB1_NO_LEGACY_MODE			(1 << 0)
#define   USB1_VBUS_SENSE_CTL_MASK		(3 << 1)
#define   USB1_VBUS_SENSE_CTL_VBUS_WAKEUP	(0 << 1)
#define   USB1_VBUS_SENSE_CTL_AB_SESS_VLD_OR_VBUS_WAKEUP \
						(1 << 1)
#define   USB1_VBUS_SENSE_CTL_AB_SESS_VLD	(2 << 1)
#define   USB1_VBUS_SENSE_CTL_A_SESS_VLD	(3 << 1)

#define ULPI_TIMING_CTRL_0	0x424
#define   ULPI_OUTPUT_PINMUX_BYP	(1 << 10)
#define   ULPI_CLKOUT_PINMUX_BYP	(1 << 11)

#define ULPI_TIMING_CTRL_1	0x428
#define   ULPI_DATA_TRIMMER_LOAD	(1 << 0)
#define   ULPI_DATA_TRIMMER_SEL(x)	(((x) & 0x7) << 1)
#define   ULPI_STPDIRNXT_TRIMMER_LOAD	(1 << 16)
#define   ULPI_STPDIRNXT_TRIMMER_SEL(x)	(((x) & 0x7) << 17)
#define   ULPI_DIR_TRIMMER_LOAD		(1 << 24)
#define   ULPI_DIR_TRIMMER_SEL(x)	(((x) & 0x7) << 25)

#define UTMIP_PLL_CFG1		0x804
#define   UTMIP_XTAL_FREQ_COUNT(x)		(((x) & 0xfff) << 0)
#define   UTMIP_PLLU_ENABLE_DLY_COUNT(x)	(((x) & 0x1f) << 27)

#define UTMIP_XCVR_CFG0		0x808
#define   UTMIP_XCVR_SETUP(x)			(((x) & 0xf) << 0)
#define   UTMIP_XCVR_LSRSLEW(x)			(((x) & 0x3) << 8)
#define   UTMIP_XCVR_LSFSLEW(x)			(((x) & 0x3) << 10)
#define   UTMIP_FORCE_PD_POWERDOWN		(1 << 14)
#define   UTMIP_FORCE_PD2_POWERDOWN		(1 << 16)
#define   UTMIP_FORCE_PDZI_POWERDOWN		(1 << 18)
#define   UTMIP_XCVR_HSSLEW_MSB(x)		(((x) & 0x7f) << 25)

#define UTMIP_BIAS_CFG0		0x80c
#define   UTMIP_OTGPD			(1 << 11)
#define   UTMIP_BIASPD			(1 << 10)

#define UTMIP_HSRX_CFG0		0x810
#define   UTMIP_ELASTIC_LIMIT(x)	(((x) & 0x1f) << 10)
#define   UTMIP_IDLE_WAIT(x)		(((x) & 0x1f) << 15)

#define UTMIP_HSRX_CFG1		0x814
#define   UTMIP_HS_SYNC_START_DLY(x)	(((x) & 0x1f) << 1)

#define UTMIP_TX_CFG0		0x820
#define   UTMIP_FS_PREABMLE_J		(1 << 19)
#define   UTMIP_HS_DISCON_DISABLE	(1 << 8)

#define UTMIP_MISC_CFG0		0x824
#define   UTMIP_DPDM_OBSERVE		(1 << 26)
#define   UTMIP_DPDM_OBSERVE_SEL(x)	(((x) & 0xf) << 27)
#define   UTMIP_DPDM_OBSERVE_SEL_FS_J	UTMIP_DPDM_OBSERVE_SEL(0xf)
#define   UTMIP_DPDM_OBSERVE_SEL_FS_K	UTMIP_DPDM_OBSERVE_SEL(0xe)
#define   UTMIP_DPDM_OBSERVE_SEL_FS_SE1 UTMIP_DPDM_OBSERVE_SEL(0xd)
#define   UTMIP_DPDM_OBSERVE_SEL_FS_SE0 UTMIP_DPDM_OBSERVE_SEL(0xc)
#define   UTMIP_SUSPEND_EXIT_ON_EDGE	(1 << 22)

#define UTMIP_MISC_CFG1		0x828
#define   UTMIP_PLL_ACTIVE_DLY_COUNT(x)	(((x) & 0x1f) << 18)
#define   UTMIP_PLLU_STABLE_COUNT(x)	(((x) & 0xfff) << 6)

#define UTMIP_DEBOUNCE_CFG0	0x82c
#define   UTMIP_BIAS_DEBOUNCE_A(x)	(((x) & 0xffff) << 0)

#define UTMIP_BAT_CHRG_CFG0	0x830
#define   UTMIP_PD_CHRG			(1 << 0)

#define UTMIP_SPARE_CFG0	0x834
#define   FUSE_SETUP_SEL		(1 << 3)

#define UTMIP_XCVR_CFG1		0x838
#define   UTMIP_FORCE_PDDISC_POWERDOWN	(1 << 0)
#define   UTMIP_FORCE_PDCHRP_POWERDOWN	(1 << 2)
#define   UTMIP_FORCE_PDDR_POWERDOWN	(1 << 4)
#define   UTMIP_XCVR_TERM_RANGE_ADJ(x)	(((x) & 0xf) << 18)

#define UTMIP_BIAS_CFG1		0x83c
#define   UTMIP_BIAS_PDTRK_COUNT(x)	(((x) & 0x1f) << 3)

static DEFINE_SPINLOCK(utmip_pad_lock);
static int utmip_pad_count;

struct tegra_xtal_freq {
	int freq;
	u8 enable_delay;
	u8 stable_count;
	u8 active_delay;
	u8 xtal_freq_count;
	u16 debounce;
};

static const struct tegra_xtal_freq tegra_freq_table[] = {
	{
		.freq = 12000000,
		.enable_delay = 0x02,
		.stable_count = 0x2F,
		.active_delay = 0x04,
		.xtal_freq_count = 0x76,
		.debounce = 0x7530,
	},
	{
		.freq = 13000000,
		.enable_delay = 0x02,
		.stable_count = 0x33,
		.active_delay = 0x05,
		.xtal_freq_count = 0x7F,
		.debounce = 0x7EF4,
	},
	{
		.freq = 19200000,
		.enable_delay = 0x03,
		.stable_count = 0x4B,
		.active_delay = 0x06,
		.xtal_freq_count = 0xBB,
		.debounce = 0xBB80,
	},
	{
		.freq = 26000000,
		.enable_delay = 0x04,
		.stable_count = 0x66,
		.active_delay = 0x09,
		.xtal_freq_count = 0xFE,
		.debounce = 0xFDE8,
	},
};

static struct tegra_utmip_config utmip_default[] = {
	[0] = {
		.hssync_start_delay = 9,
		.idle_wait_delay = 17,
		.elastic_limit = 16,
		.term_range_adj = 6,
		.xcvr_setup = 9,
		.xcvr_lsfslew = 1,
		.xcvr_lsrslew = 1,
	},
	[2] = {
		.hssync_start_delay = 9,
		.idle_wait_delay = 17,
		.elastic_limit = 16,
		.term_range_adj = 6,
		.xcvr_setup = 9,
		.xcvr_lsfslew = 2,
		.xcvr_lsrslew = 2,
	},
};

static int utmip_pad_open(struct tegra_usb_phy *phy)
{
	phy->pad_clk = clk_get_sys("utmip-pad", NULL);
	if (IS_ERR(phy->pad_clk)) {
		pr_err("%s: can't get utmip pad clock\n", __func__);
		return PTR_ERR(phy->pad_clk);
	}

	if (phy->is_legacy_phy) {
		phy->pad_regs = phy->regs;
	} else {
		phy->pad_regs = ioremap(TEGRA_USB_BASE, TEGRA_USB_SIZE);
		if (!phy->pad_regs) {
			pr_err("%s: can't remap usb registers\n", __func__);
			clk_put(phy->pad_clk);
			return -ENOMEM;
		}
	}
	return 0;
}

static void utmip_pad_close(struct tegra_usb_phy *phy)
{
	if (!phy->is_legacy_phy)
		iounmap(phy->pad_regs);
	clk_put(phy->pad_clk);
}

static void utmip_pad_power_on(struct tegra_usb_phy *phy)
{
	unsigned long val, flags;
	void __iomem *base = phy->pad_regs;

	clk_prepare_enable(phy->pad_clk);

	spin_lock_irqsave(&utmip_pad_lock, flags);

	if (utmip_pad_count++ == 0) {
		val = readl(base + UTMIP_BIAS_CFG0);
		val &= ~(UTMIP_OTGPD | UTMIP_BIASPD);
		writel(val, base + UTMIP_BIAS_CFG0);
	}

	spin_unlock_irqrestore(&utmip_pad_lock, flags);

	clk_disable_unprepare(phy->pad_clk);
}

static int utmip_pad_power_off(struct tegra_usb_phy *phy)
{
	unsigned long val, flags;
	void __iomem *base = phy->pad_regs;

	if (!utmip_pad_count) {
		pr_err("%s: utmip pad already powered off\n", __func__);
		return -EINVAL;
	}

	clk_prepare_enable(phy->pad_clk);

	spin_lock_irqsave(&utmip_pad_lock, flags);

	if (--utmip_pad_count == 0) {
		val = readl(base + UTMIP_BIAS_CFG0);
		val |= UTMIP_OTGPD | UTMIP_BIASPD;
		writel(val, base + UTMIP_BIAS_CFG0);
	}

	spin_unlock_irqrestore(&utmip_pad_lock, flags);

	clk_disable_unprepare(phy->pad_clk);

	return 0;
}

static int utmi_wait_register(void __iomem *reg, u32 mask, u32 result)
{
	unsigned long timeout = 2000;
	do {
		if ((readl(reg) & mask) == result)
			return 0;
		udelay(1);
		timeout--;
	} while (timeout);
	return -1;
}

static void utmi_phy_clk_disable(struct tegra_usb_phy *phy)
{
	unsigned long val;
	void __iomem *base = phy->regs;

	if (phy->is_legacy_phy) {
		val = readl(base + USB_SUSP_CTRL);
		val |= USB_SUSP_SET;
		writel(val, base + USB_SUSP_CTRL);

		udelay(10);

		val = readl(base + USB_SUSP_CTRL);
		val &= ~USB_SUSP_SET;
		writel(val, base + USB_SUSP_CTRL);
	} else
		phy->set_phcd(&phy->u_phy, true);

	if (utmi_wait_register(base + USB_SUSP_CTRL, USB_PHY_CLK_VALID, 0) < 0)
		pr_err("%s: timeout waiting for phy to stabilize\n", __func__);
}

static void utmi_phy_clk_enable(struct tegra_usb_phy *phy)
{
	unsigned long val;
	void __iomem *base = phy->regs;

	if (phy->is_legacy_phy) {
		val = readl(base + USB_SUSP_CTRL);
		val |= USB_SUSP_CLR;
		writel(val, base + USB_SUSP_CTRL);

		udelay(10);

		val = readl(base + USB_SUSP_CTRL);
		val &= ~USB_SUSP_CLR;
		writel(val, base + USB_SUSP_CTRL);
	} else
		phy->set_phcd(&phy->u_phy, false);

	if (utmi_wait_register(base + USB_SUSP_CTRL, USB_PHY_CLK_VALID,
						     USB_PHY_CLK_VALID))
		pr_err("%s: timeout waiting for phy to stabilize\n", __func__);
}

static int utmi_phy_power_on(struct tegra_usb_phy *phy)
{
	unsigned long val;
	void __iomem *base = phy->regs;
	struct tegra_utmip_config *config = phy->config;

	val = readl(base + USB_SUSP_CTRL);
	val |= UTMIP_RESET;
	writel(val, base + USB_SUSP_CTRL);

	if (phy->is_legacy_phy) {
		val = readl(base + USB1_LEGACY_CTRL);
		val |= USB1_NO_LEGACY_MODE;
		writel(val, base + USB1_LEGACY_CTRL);
	}

	val = readl(base + UTMIP_TX_CFG0);
	val &= ~UTMIP_FS_PREABMLE_J;
	writel(val, base + UTMIP_TX_CFG0);

	val = readl(base + UTMIP_HSRX_CFG0);
	val &= ~(UTMIP_IDLE_WAIT(~0) | UTMIP_ELASTIC_LIMIT(~0));
	val |= UTMIP_IDLE_WAIT(config->idle_wait_delay);
	val |= UTMIP_ELASTIC_LIMIT(config->elastic_limit);
	writel(val, base + UTMIP_HSRX_CFG0);

	val = readl(base + UTMIP_HSRX_CFG1);
	val &= ~UTMIP_HS_SYNC_START_DLY(~0);
	val |= UTMIP_HS_SYNC_START_DLY(config->hssync_start_delay);
	writel(val, base + UTMIP_HSRX_CFG1);

	val = readl(base + UTMIP_DEBOUNCE_CFG0);
	val &= ~UTMIP_BIAS_DEBOUNCE_A(~0);
	val |= UTMIP_BIAS_DEBOUNCE_A(phy->freq->debounce);
	writel(val, base + UTMIP_DEBOUNCE_CFG0);

	val = readl(base + UTMIP_MISC_CFG0);
	val &= ~UTMIP_SUSPEND_EXIT_ON_EDGE;
	writel(val, base + UTMIP_MISC_CFG0);

	val = readl(base + UTMIP_MISC_CFG1);
	val &= ~(UTMIP_PLL_ACTIVE_DLY_COUNT(~0) | UTMIP_PLLU_STABLE_COUNT(~0));
	val |= UTMIP_PLL_ACTIVE_DLY_COUNT(phy->freq->active_delay) |
		UTMIP_PLLU_STABLE_COUNT(phy->freq->stable_count);
	writel(val, base + UTMIP_MISC_CFG1);

	val = readl(base + UTMIP_PLL_CFG1);
	val &= ~(UTMIP_XTAL_FREQ_COUNT(~0) | UTMIP_PLLU_ENABLE_DLY_COUNT(~0));
	val |= UTMIP_XTAL_FREQ_COUNT(phy->freq->xtal_freq_count) |
		UTMIP_PLLU_ENABLE_DLY_COUNT(phy->freq->enable_delay);
	writel(val, base + UTMIP_PLL_CFG1);

	if (phy->mode == TEGRA_USB_PHY_MODE_DEVICE) {
		val = readl(base + USB_SUSP_CTRL);
		val &= ~(USB_WAKE_ON_CNNT_EN_DEV | USB_WAKE_ON_DISCON_EN_DEV);
		writel(val, base + USB_SUSP_CTRL);
	}

	utmip_pad_power_on(phy);

	val = readl(base + UTMIP_XCVR_CFG0);
	val &= ~(UTMIP_FORCE_PD_POWERDOWN | UTMIP_FORCE_PD2_POWERDOWN |
		 UTMIP_FORCE_PDZI_POWERDOWN | UTMIP_XCVR_SETUP(~0) |
		 UTMIP_XCVR_LSFSLEW(~0) | UTMIP_XCVR_LSRSLEW(~0) |
		 UTMIP_XCVR_HSSLEW_MSB(~0));
	val |= UTMIP_XCVR_SETUP(config->xcvr_setup);
	val |= UTMIP_XCVR_LSFSLEW(config->xcvr_lsfslew);
	val |= UTMIP_XCVR_LSRSLEW(config->xcvr_lsrslew);
	writel(val, base + UTMIP_XCVR_CFG0);

	val = readl(base + UTMIP_XCVR_CFG1);
	val &= ~(UTMIP_FORCE_PDDISC_POWERDOWN | UTMIP_FORCE_PDCHRP_POWERDOWN |
		 UTMIP_FORCE_PDDR_POWERDOWN | UTMIP_XCVR_TERM_RANGE_ADJ(~0));
	val |= UTMIP_XCVR_TERM_RANGE_ADJ(config->term_range_adj);
	writel(val, base + UTMIP_XCVR_CFG1);

	val = readl(base + UTMIP_BAT_CHRG_CFG0);
	val &= ~UTMIP_PD_CHRG;
	writel(val, base + UTMIP_BAT_CHRG_CFG0);

	val = readl(base + UTMIP_BIAS_CFG1);
	val &= ~UTMIP_BIAS_PDTRK_COUNT(~0);
	val |= UTMIP_BIAS_PDTRK_COUNT(0x5);
	writel(val, base + UTMIP_BIAS_CFG1);

	if (phy->is_legacy_phy) {
		val = readl(base + UTMIP_SPARE_CFG0);
		if (phy->mode == TEGRA_USB_PHY_MODE_DEVICE)
			val &= ~FUSE_SETUP_SEL;
		else
			val |= FUSE_SETUP_SEL;
		writel(val, base + UTMIP_SPARE_CFG0);
	} else {
		val = readl(base + USB_SUSP_CTRL);
		val |= UTMIP_PHY_ENABLE;
		writel(val, base + USB_SUSP_CTRL);
	}

	val = readl(base + USB_SUSP_CTRL);
	val &= ~UTMIP_RESET;
	writel(val, base + USB_SUSP_CTRL);

	if (phy->is_legacy_phy) {
		val = readl(base + USB1_LEGACY_CTRL);
		val &= ~USB1_VBUS_SENSE_CTL_MASK;
		val |= USB1_VBUS_SENSE_CTL_A_SESS_VLD;
		writel(val, base + USB1_LEGACY_CTRL);

		val = readl(base + USB_SUSP_CTRL);
		val &= ~USB_SUSP_SET;
		writel(val, base + USB_SUSP_CTRL);
	}

	utmi_phy_clk_enable(phy);

	if (!phy->is_legacy_phy)
		phy->set_pts(&phy->u_phy, 0);

	return 0;
}

static int utmi_phy_power_off(struct tegra_usb_phy *phy)
{
	unsigned long val;
	void __iomem *base = phy->regs;

	utmi_phy_clk_disable(phy);

	if (phy->mode == TEGRA_USB_PHY_MODE_DEVICE) {
		val = readl(base + USB_SUSP_CTRL);
		val &= ~USB_WAKEUP_DEBOUNCE_COUNT(~0);
		val |= USB_WAKE_ON_CNNT_EN_DEV | USB_WAKEUP_DEBOUNCE_COUNT(5);
		writel(val, base + USB_SUSP_CTRL);
	}

	val = readl(base + USB_SUSP_CTRL);
	val |= UTMIP_RESET;
	writel(val, base + USB_SUSP_CTRL);

	val = readl(base + UTMIP_BAT_CHRG_CFG0);
	val |= UTMIP_PD_CHRG;
	writel(val, base + UTMIP_BAT_CHRG_CFG0);

	val = readl(base + UTMIP_XCVR_CFG0);
	val |= UTMIP_FORCE_PD_POWERDOWN | UTMIP_FORCE_PD2_POWERDOWN |
	       UTMIP_FORCE_PDZI_POWERDOWN;
	writel(val, base + UTMIP_XCVR_CFG0);

	val = readl(base + UTMIP_XCVR_CFG1);
	val |= UTMIP_FORCE_PDDISC_POWERDOWN | UTMIP_FORCE_PDCHRP_POWERDOWN |
	       UTMIP_FORCE_PDDR_POWERDOWN;
	writel(val, base + UTMIP_XCVR_CFG1);

	return utmip_pad_power_off(phy);
}

static void utmi_phy_preresume(struct tegra_usb_phy *phy)
{
	unsigned long val;
	void __iomem *base = phy->regs;

	val = readl(base + UTMIP_TX_CFG0);
	val |= UTMIP_HS_DISCON_DISABLE;
	writel(val, base + UTMIP_TX_CFG0);
}

static void utmi_phy_postresume(struct tegra_usb_phy *phy)
{
	unsigned long val;
	void __iomem *base = phy->regs;

	val = readl(base + UTMIP_TX_CFG0);
	val &= ~UTMIP_HS_DISCON_DISABLE;
	writel(val, base + UTMIP_TX_CFG0);
}

static void utmi_phy_restore_start(struct tegra_usb_phy *phy,
				   enum tegra_usb_phy_port_speed port_speed)
{
	unsigned long val;
	void __iomem *base = phy->regs;

	val = readl(base + UTMIP_MISC_CFG0);
	val &= ~UTMIP_DPDM_OBSERVE_SEL(~0);
	if (port_speed == TEGRA_USB_PHY_PORT_SPEED_LOW)
		val |= UTMIP_DPDM_OBSERVE_SEL_FS_K;
	else
		val |= UTMIP_DPDM_OBSERVE_SEL_FS_J;
	writel(val, base + UTMIP_MISC_CFG0);
	udelay(1);

	val = readl(base + UTMIP_MISC_CFG0);
	val |= UTMIP_DPDM_OBSERVE;
	writel(val, base + UTMIP_MISC_CFG0);
	udelay(10);
}

static void utmi_phy_restore_end(struct tegra_usb_phy *phy)
{
	unsigned long val;
	void __iomem *base = phy->regs;

	val = readl(base + UTMIP_MISC_CFG0);
	val &= ~UTMIP_DPDM_OBSERVE;
	writel(val, base + UTMIP_MISC_CFG0);
	udelay(10);
}

static int ulpi_phy_power_on(struct tegra_usb_phy *phy)
{
	int ret;
	unsigned long val;
	void __iomem *base = phy->regs;

	ret = gpio_direction_output(phy->reset_gpio, 0);
	if (ret < 0) {
		dev_err(phy->dev, "gpio %d not set to 0\n", phy->reset_gpio);
		return ret;
	}
	msleep(5);
	ret = gpio_direction_output(phy->reset_gpio, 1);
	if (ret < 0) {
		dev_err(phy->dev, "gpio %d not set to 1\n", phy->reset_gpio);
		return ret;
	}

	clk_prepare_enable(phy->clk);
	msleep(1);

	val = readl(base + USB_SUSP_CTRL);
	val |= UHSIC_RESET;
	writel(val, base + USB_SUSP_CTRL);

	val = readl(base + ULPI_TIMING_CTRL_0);
	val |= ULPI_OUTPUT_PINMUX_BYP | ULPI_CLKOUT_PINMUX_BYP;
	writel(val, base + ULPI_TIMING_CTRL_0);

	val = readl(base + USB_SUSP_CTRL);
	val |= ULPI_PHY_ENABLE;
	writel(val, base + USB_SUSP_CTRL);

	val = 0;
	writel(val, base + ULPI_TIMING_CTRL_1);

	val |= ULPI_DATA_TRIMMER_SEL(4);
	val |= ULPI_STPDIRNXT_TRIMMER_SEL(4);
	val |= ULPI_DIR_TRIMMER_SEL(4);
	writel(val, base + ULPI_TIMING_CTRL_1);
	udelay(10);

	val |= ULPI_DATA_TRIMMER_LOAD;
	val |= ULPI_STPDIRNXT_TRIMMER_LOAD;
	val |= ULPI_DIR_TRIMMER_LOAD;
	writel(val, base + ULPI_TIMING_CTRL_1);

	/* Fix VbusInvalid due to floating VBUS */
	ret = usb_phy_io_write(phy->ulpi, 0x40, 0x08);
	if (ret) {
		pr_err("%s: ulpi write failed\n", __func__);
		return ret;
	}

	ret = usb_phy_io_write(phy->ulpi, 0x80, 0x0B);
	if (ret) {
		pr_err("%s: ulpi write failed\n", __func__);
		return ret;
	}

	val = readl(base + USB_SUSP_CTRL);
	val |= USB_SUSP_CLR;
	writel(val, base + USB_SUSP_CTRL);
	udelay(100);

	val = readl(base + USB_SUSP_CTRL);
	val &= ~USB_SUSP_CLR;
	writel(val, base + USB_SUSP_CTRL);

	return 0;
}

static int ulpi_phy_power_off(struct tegra_usb_phy *phy)
{
	clk_disable(phy->clk);
	return gpio_direction_output(phy->reset_gpio, 0);
}

static int	tegra_phy_init(struct usb_phy *x)
{
	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);
	struct tegra_ulpi_config *ulpi_config;
	int err;

	if (phy->is_ulpi_phy) {
		ulpi_config = phy->config;
		phy->clk = clk_get_sys(NULL, ulpi_config->clk);
		if (IS_ERR(phy->clk)) {
			pr_err("%s: can't get ulpi clock\n", __func__);
			return PTR_ERR(phy->clk);
		}

		phy->reset_gpio =
			of_get_named_gpio(phy->dev->of_node,
					  "nvidia,phy-reset-gpio", 0);
		if (!gpio_is_valid(phy->reset_gpio)) {
			dev_err(phy->dev, "invalid gpio: %d\n",
				phy->reset_gpio);
			err = phy->reset_gpio;
			goto cleanup_clk_get;
		}

		err = gpio_request(phy->reset_gpio, "ulpi_phy_reset_b");
		if (err < 0) {
			dev_err(phy->dev, "request failed for gpio: %d\n",
			       phy->reset_gpio);
			goto cleanup_clk_get;
		}

		err = gpio_direction_output(phy->reset_gpio, 0);
		if (err < 0) {
			dev_err(phy->dev, "gpio %d direction not set to output\n",
			       phy->reset_gpio);
			goto cleanup_gpio_req;
		}

		phy->ulpi = otg_ulpi_create(&ulpi_viewport_access_ops, 0);
		if (!phy->ulpi) {
			dev_err(phy->dev, "otg_ulpi_create returned NULL\n");
			err = -ENOMEM;
			goto cleanup_gpio_req;
		}

		phy->ulpi->io_priv = phy->regs + ULPI_VIEWPORT;
	} else {
		err = utmip_pad_open(phy);
		if (err < 0)
			return err;
	}
	return 0;
cleanup_gpio_req:
	gpio_free(phy->reset_gpio);
cleanup_clk_get:
	clk_put(phy->clk);
	return err;
}

static void tegra_usb_phy_close(struct usb_phy *x)
{
	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);

	if (phy->is_ulpi_phy)
		clk_put(phy->clk);
	else
		utmip_pad_close(phy);
	clk_disable_unprepare(phy->pll_u);
	clk_put(phy->pll_u);
	kfree(phy);
}

static int tegra_usb_phy_power_on(struct tegra_usb_phy *phy)
{
	if (phy->is_ulpi_phy)
		return ulpi_phy_power_on(phy);
	else
		return utmi_phy_power_on(phy);
}

static int tegra_usb_phy_power_off(struct tegra_usb_phy *phy)
{
	if (phy->is_ulpi_phy)
		return ulpi_phy_power_off(phy);
	else
		return utmi_phy_power_off(phy);
}

static int	tegra_usb_phy_suspend(struct usb_phy *x, int suspend)
{
	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);
	if (suspend)
		return tegra_usb_phy_power_off(phy);
	else
		return tegra_usb_phy_power_on(phy);
}

struct tegra_usb_phy *tegra_usb_phy_open(struct device *dev, int instance,
	void __iomem *regs, void *config,
	void (*set_pts)(struct usb_phy *x, u8 pts_val),
	void (*set_phcd)(struct usb_phy *x, bool enable))

{
	struct tegra_usb_phy *phy;
	unsigned long parent_rate;
	int i;
	int err;
	struct device_node *np = dev->of_node;

	phy = kzalloc(sizeof(struct tegra_usb_phy), GFP_KERNEL);
	if (!phy)
		return ERR_PTR(-ENOMEM);

	phy->instance = instance;
	phy->regs = regs;
	phy->config = config;
	phy->dev = dev;
	phy->is_legacy_phy =
		of_property_read_bool(np, "nvidia,has-legacy-mode");
	phy->set_pts = set_pts;
	phy->set_phcd = set_phcd;
	err = of_property_match_string(np, "phy_type", "ulpi");
	if (err < 0)
		phy->is_ulpi_phy = false;
	else
		phy->is_ulpi_phy = true;

	err = of_property_match_string(np, "dr_mode", "otg");
	if (err < 0) {
		err = of_property_match_string(np, "dr_mode", "peripheral");
		if (err < 0)
			phy->mode = TEGRA_USB_PHY_MODE_HOST;
		else
			phy->mode = TEGRA_USB_PHY_MODE_DEVICE;
	} else
		phy->mode = TEGRA_USB_PHY_MODE_OTG;

	if (!phy->config) {
		if (phy->is_ulpi_phy) {
			pr_err("%s: ulpi phy configuration missing", __func__);
			err = -EINVAL;
			goto err0;
		} else {
			phy->config = &utmip_default[instance];
		}
	}

	phy->pll_u = clk_get_sys(NULL, "pll_u");
	if (IS_ERR(phy->pll_u)) {
		pr_err("Can't get pll_u clock\n");
		err = PTR_ERR(phy->pll_u);
		goto err0;
	}
	clk_prepare_enable(phy->pll_u);

	parent_rate = clk_get_rate(clk_get_parent(phy->pll_u));
	for (i = 0; i < ARRAY_SIZE(tegra_freq_table); i++) {
		if (tegra_freq_table[i].freq == parent_rate) {
			phy->freq = &tegra_freq_table[i];
			break;
		}
	}
	if (!phy->freq) {
		pr_err("invalid pll_u parent rate %ld\n", parent_rate);
		err = -EINVAL;
		goto err1;
	}

	phy->u_phy.init = tegra_phy_init;
	phy->u_phy.shutdown = tegra_usb_phy_close;
	phy->u_phy.set_suspend = tegra_usb_phy_suspend;

	return phy;

err1:
	clk_disable_unprepare(phy->pll_u);
	clk_put(phy->pll_u);
err0:
	kfree(phy);
	return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(tegra_usb_phy_open);

void tegra_usb_phy_preresume(struct usb_phy *x)
{
	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);

	if (!phy->is_ulpi_phy)
		utmi_phy_preresume(phy);
}
EXPORT_SYMBOL_GPL(tegra_usb_phy_preresume);

void tegra_usb_phy_postresume(struct usb_phy *x)
{
	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);

	if (!phy->is_ulpi_phy)
		utmi_phy_postresume(phy);
}
EXPORT_SYMBOL_GPL(tegra_usb_phy_postresume);

void tegra_ehci_phy_restore_start(struct usb_phy *x,
				 enum tegra_usb_phy_port_speed port_speed)
{
	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);

	if (!phy->is_ulpi_phy)
		utmi_phy_restore_start(phy, port_speed);
}
EXPORT_SYMBOL_GPL(tegra_ehci_phy_restore_start);

void tegra_ehci_phy_restore_end(struct usb_phy *x)
{
	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);

	if (!phy->is_ulpi_phy)
		utmi_phy_restore_end(phy);
}
EXPORT_SYMBOL_GPL(tegra_ehci_phy_restore_end);