path: root/drivers/usb/host/ehci-tegra.c

/*
 * EHCI-compliant USB host controller driver for NVIDIA Tegra SoCs
 *
 * Copyright (C) 2010 Google, Inc.
 * Copyright (C) 2009 - 2011 NVIDIA Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * 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/clk.h>
#include <linux/platform_device.h>
#include <linux/platform_data/tegra_usb.h>
#include <linux/irq.h>
#include <linux/usb/otg.h>
#include <mach/usb_phy.h>
#include <mach/iomap.h>

#define TEGRA_USB_PORTSC_PHCD			(1 << 23)

#define TEGRA_USB_SUSP_CTRL_OFFSET		0x400
#define TEGRA_USB_SUSP_CLR			(1 << 5)
#define TEGRA_USB_PHY_CLK_VALID			(1 << 7)
#define TEGRA_USB_SRT				(1 << 25)

#define TEGRA_LVL2_CLK_GATE_OVRB		0xfc
#define TEGRA_USB2_CLK_OVR_ON			(1 << 10)

#define TEGRA_USB_DMA_ALIGN 32

#define STS_SRI	(1<<7)	/*	SOF Recieved	*/

struct tegra_ehci_hcd {
	struct ehci_hcd *ehci;
	struct tegra_usb_phy *phy;
	struct clk *clk;
	struct clk *emc_clk;
	struct otg_transceiver *transceiver;
	int host_resumed;
	int bus_suspended;
	int port_resuming;
	int power_down_on_bus_suspend;
	struct delayed_work work;
	enum tegra_usb_phy_port_speed port_speed;
};

static void tegra_ehci_power_up(struct usb_hcd *hcd)
{
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);

	clk_enable(tegra->emc_clk);
	clk_enable(tegra->clk);
	tegra_usb_phy_power_on(tegra->phy);
	tegra->host_resumed = 1;
}

static void tegra_ehci_power_down(struct usb_hcd *hcd)
{
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);

	tegra->host_resumed = 0;
	tegra_usb_phy_power_off(tegra->phy);
	clk_disable(tegra->clk);
	clk_disable(tegra->emc_clk);
}

static int tegra_ehci_hub_control(
	struct usb_hcd	*hcd,
	u16		typeReq,
	u16		wValue,
	u16		wIndex,
	char		*buf,
	u16		wLength
)
{
	struct ehci_hcd	*ehci = hcd_to_ehci(hcd);
	int		ports = HCS_N_PORTS(ehci->hcs_params);
	u32		temp, status;
	u32 __iomem	*status_reg;
	u32		usbsts_reg;
	unsigned long	flags;
	int		retval = 0;
	unsigned	selector;
	struct		tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);
	bool		hsic = false;

	if (tegra->phy->instance == 1) {
		struct tegra_ulpi_config *config = tegra->phy->config;
		hsic = (config->inf_type == TEGRA_USB_UHSIC);
	}

	status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1];

	spin_lock_irqsave(&ehci->lock, flags);

	/*
	 * In ehci_hub_control() for USB_PORT_FEAT_ENABLE clears the other bits
	 * that are write on clear, by writing back the register read value, so
	 * USB_PORT_FEAT_ENABLE is handled by masking the set on clear bits
	 */
	if (typeReq == ClearPortFeature && wValue == USB_PORT_FEAT_ENABLE) {
		temp = ehci_readl(ehci, status_reg) & ~PORT_RWC_BITS;
		ehci_writel(ehci, temp & ~PORT_PE, status_reg);
		goto done;
	} else if (typeReq == GetPortStatus) {
		temp = ehci_readl(ehci, status_reg);
		if (tegra->port_resuming && !(temp & PORT_SUSPEND)) {
			/* Resume completed, re-enable disconnect detection */
			tegra->port_resuming = 0;
			tegra_usb_phy_postresume(tegra->phy);
		}
	} else if (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_SUSPEND) {
		temp = ehci_readl(ehci, status_reg);
		if ((temp & PORT_PE) == 0 || (temp & PORT_RESET) != 0) {
			retval = -EPIPE;
			goto done;
		}

		temp &= ~PORT_WKCONN_E;
		temp |= PORT_WKDISC_E | PORT_WKOC_E;
		ehci_writel(ehci, temp | PORT_SUSPEND, status_reg);
		/* Need a 4ms delay before the controller goes to suspend */
		mdelay(4);

		/*
		 * If a transaction is in progress, there may be a delay in
		 * suspending the port. Poll until the port is suspended.
		 */
		if (handshake(ehci, status_reg, PORT_SUSPEND,
						PORT_SUSPEND, 5000))
			pr_err("%s: timeout waiting for SUSPEND\n", __func__);

		set_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
		goto done;
	}

	/*
	 * Tegra host controller will time the resume operation to clear the bit
	 * when the port control state switches to HS or FS Idle. This behavior
	 * is different from EHCI where the host controller driver is required
	 * to set this bit to a zero after the resume duration is timed in the
	 * driver.
	 */
	else if (typeReq == ClearPortFeature &&
					wValue == USB_PORT_FEAT_SUSPEND) {
		temp = ehci_readl(ehci, status_reg);
		if ((temp & PORT_RESET) || !(temp & PORT_PE)) {
			retval = -EPIPE;
			goto done;
		}

		if (!(temp & PORT_SUSPEND))
			goto done;

		/* Disable disconnect detection during port resume */
		tegra_usb_phy_preresume(tegra->phy);

		ehci->reset_done[wIndex-1] = jiffies + msecs_to_jiffies(25);

		ehci_dbg(ehci, "%s:USBSTS = 0x%x", __func__,
			ehci_readl(ehci, &ehci->regs->status));
		usbsts_reg = ehci_readl(ehci, &ehci->regs->status);
		ehci_writel(ehci, usbsts_reg, &ehci->regs->status);
		usbsts_reg = ehci_readl(ehci, &ehci->regs->status);
		udelay(20);

		if (handshake(ehci, &ehci->regs->status, STS_SRI, STS_SRI, 2000))
			pr_err("%s: timeout set for STS_SRI\n", __func__);

		usbsts_reg = ehci_readl(ehci, &ehci->regs->status);
		ehci_writel(ehci, usbsts_reg, &ehci->regs->status);

		if (handshake(ehci, &ehci->regs->status, STS_SRI, 0, 2000))
			pr_err("%s: timeout clear STS_SRI\n", __func__);

		if (handshake(ehci, &ehci->regs->status, STS_SRI, STS_SRI, 2000))
			pr_err("%s: timeout set STS_SRI\n", __func__);

		udelay(20);
		temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
		/* start resume signalling */
		ehci_writel(ehci, temp | PORT_RESUME, status_reg);

		spin_unlock_irqrestore(&ehci->lock, flags);
		msleep(20);
		spin_lock_irqsave(&ehci->lock, flags);

		/* Poll until the controller clears RESUME and SUSPEND */
		if (handshake(ehci, status_reg, PORT_RESUME, 0, 2000))
			pr_err("%s: timeout waiting for RESUME\n", __func__);
		if (handshake(ehci, status_reg, PORT_SUSPEND, 0, 2000))
			pr_err("%s: timeout waiting for SUSPEND\n", __func__);

		ehci->reset_done[wIndex-1] = 0;

		tegra->port_resuming = 1;
		goto done;
	}

	/* Handle port reset here */
	if ((hsic) && (typeReq == SetPortFeature) &&
		((wValue == USB_PORT_FEAT_RESET) || (wValue == USB_PORT_FEAT_POWER))) {
		selector = wIndex >> 8;
		wIndex &= 0xff;
		if (!wIndex || wIndex > ports) {
			retval = -EPIPE;
			goto done;
		}
		wIndex--;
		status = 0;
		temp = ehci_readl(ehci, status_reg);
		if (temp & PORT_OWNER)
			goto done;
		temp &= ~PORT_RWC_BITS;

		switch (wValue) {
		case USB_PORT_FEAT_RESET:
		{
			if (temp & PORT_RESUME) {
				retval = -EPIPE;
				goto done;
			}
			/* line status bits may report this as low speed,
			* which can be fine if this root hub has a
			* transaction translator built in.
			*/
			if ((temp & (PORT_PE|PORT_CONNECT)) == PORT_CONNECT
					&& !ehci_is_TDI(ehci) && PORT_USB11 (temp)) {
				ehci_dbg (ehci, "port %d low speed --> companion\n", wIndex + 1);
				temp |= PORT_OWNER;
				ehci_writel(ehci, temp, status_reg);
			} else {
				ehci_vdbg(ehci, "port %d reset\n", wIndex + 1);
				temp &= ~PORT_PE;
				/*
				* caller must wait, then call GetPortStatus
				* usb 2.0 spec says 50 ms resets on root
				*/
				ehci->reset_done[wIndex] = jiffies + msecs_to_jiffies(50);
				ehci_writel(ehci, temp, status_reg);
				if (hsic && (wIndex == 0))
					tegra_usb_phy_bus_reset(tegra->phy);
			}

			break;
		}
		case USB_PORT_FEAT_POWER:
		{
			if (HCS_PPC(ehci->hcs_params))
				ehci_writel(ehci, temp | PORT_POWER, status_reg);
			if (hsic && (wIndex == 0))
				tegra_usb_phy_bus_connect(tegra->phy);
			break;
		}
		}
		goto done;
	}

	spin_unlock_irqrestore(&ehci->lock, flags);

	/* Handle the hub control events here */
	return ehci_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
done:
	spin_unlock_irqrestore(&ehci->lock, flags);
	return retval;
}

static void tegra_ehci_restart(struct usb_hcd *hcd)
{
	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
	unsigned int temp;

	ehci_reset(ehci);

	/* setup the frame list and Async q heads */
	ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
	ehci_writel(ehci, (u32)ehci->async->qh_dma, &ehci->regs->async_next);
	/* setup the command register and set the controller in RUN mode */
	ehci->command &= ~(CMD_LRESET|CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
	ehci->command |= CMD_RUN;
	ehci_writel(ehci, ehci->command, &ehci->regs->command);

	/* Enable the root Port Power */
	if (HCS_PPC(ehci->hcs_params)) {
		temp = ehci_readl(ehci, &ehci->regs->port_status[0]);
		ehci_writel(ehci, temp | PORT_POWER, &ehci->regs->port_status[0]);
	}

	down_write(&ehci_cf_port_reset_rwsem);
	hcd->state = HC_STATE_RUNNING;
	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
	/* flush posted writes */
	ehci_readl(ehci, &ehci->regs->command);
	up_write(&ehci_cf_port_reset_rwsem);

	/* Turn On Interrupts */
	ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);
}

static int tegra_usb_suspend(struct usb_hcd *hcd)
{
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);
	struct ehci_regs __iomem *hw = tegra->ehci->regs;
	unsigned long flags;
	int hsic = 0;
	struct tegra_ulpi_config *config;

	if (tegra->phy->instance == 1) {
		config = tegra->phy->config;
		hsic = (config->inf_type == TEGRA_USB_UHSIC);
	}

	spin_lock_irqsave(&tegra->ehci->lock, flags);

	tegra->port_speed = (readl(&hw->port_status[0]) >> 26) & 0x3;
	ehci_halt(tegra->ehci);
	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);

	spin_unlock_irqrestore(&tegra->ehci->lock, flags);

	tegra_ehci_power_down(hcd);
	return 0;
}

static int tegra_usb_resume(struct usb_hcd *hcd)
{
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);
	struct usb_device *udev = hcd->self.root_hub;
	struct ehci_hcd	*ehci = hcd_to_ehci(hcd);
	struct ehci_regs __iomem *hw = ehci->regs;
	unsigned long val;
	int hsic = 0;
	struct tegra_ulpi_config *config;

	if (tegra->phy->instance == 1) {
		config = tegra->phy->config;
		hsic = (config->inf_type == TEGRA_USB_UHSIC);
	}

	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
	tegra_ehci_power_up(hcd);

	if (tegra->port_speed > TEGRA_USB_PHY_PORT_SPEED_HIGH) {
		/* Wait for the phy to detect new devices
		 * before we restart the controller */
		msleep(10);
		goto restart;
	}

	/* Force the phy to keep data lines in suspend state */
	tegra_ehci_phy_restore_start(tegra->phy, tegra->port_speed);

	/* Enable host mode */
	tdi_reset(ehci);

	/* Enable Port Power */
	val = readl(&hw->port_status[0]);
	val |= PORT_POWER;
	writel(val, &hw->port_status[0]);
	udelay(10);

	/* Check if the phy resume from LP0. When the phy resume from LP0
	 * USB register will be reset. */
	if (!readl(&hw->async_next)) {
		/* Program the field PTC based on the saved speed mode */
		val = readl(&hw->port_status[0]);
		val &= ~PORT_TEST(~0);
		if (tegra->port_speed == TEGRA_USB_PHY_PORT_SPEED_HIGH)
			val |= PORT_TEST_FORCE;
		else if (tegra->port_speed == TEGRA_USB_PHY_PORT_SPEED_FULL)
			val |= PORT_TEST(6);
		else if (tegra->port_speed == TEGRA_USB_PHY_PORT_SPEED_LOW)
			val |= PORT_TEST(7);
		writel(val, &hw->port_status[0]);
		udelay(10);

		/* Disable test mode by setting PTC field to NORMAL_OP */
		val = readl(&hw->port_status[0]);
		val &= ~PORT_TEST(~0);
		writel(val, &hw->port_status[0]);
		udelay(10);
	}

	/* Poll until CCS is enabled */
	if (handshake(ehci, &hw->port_status[0], PORT_CONNECT,
						 PORT_CONNECT, 2000)) {
		pr_err("%s: timeout waiting for PORT_CONNECT\n", __func__);
		goto restart;
	}

	/* Poll until PE is enabled */
	if (handshake(ehci, &hw->port_status[0], PORT_PE,
						 PORT_PE, 2000)) {
		pr_err("%s: timeout waiting for USB_PORTSC1_PE\n", __func__);
		goto restart;
	}

	/* Clear the PCI status, to avoid an interrupt taken upon resume */
	val = readl(&hw->status);
	val |= STS_PCD;
	writel(val, &hw->status);

	/* Put controller in suspend mode by writing 1 to SUSP bit of PORTSC */
	val = readl(&hw->port_status[0]);
	if ((val & PORT_POWER) && (val & PORT_PE)) {
		val |= PORT_SUSPEND;
		writel(val, &hw->port_status[0]);
		/* Need a 4ms delay before the controller goes to suspend */
		mdelay(4);

		/* Wait until port suspend completes */
		if (handshake(ehci, &hw->port_status[0], PORT_SUSPEND,
							 PORT_SUSPEND, 1000)) {
			pr_err("%s: timeout waiting for PORT_SUSPEND\n",
								__func__);
			goto restart;
		}
	}

	tegra_ehci_phy_restore_end(tegra->phy);
	return 0;

restart:
	if (tegra->port_speed <= TEGRA_USB_PHY_PORT_SPEED_HIGH)
		tegra_ehci_phy_restore_end(tegra->phy);
	if (hsic) {
		val = readl(&hw->port_status[0]);
		if (!((val & PORT_POWER) && (val & PORT_PE))) {
			tegra_ehci_restart(hcd);
			usb_set_device_state(udev, USB_STATE_CONFIGURED);
		}
		tegra_usb_phy_bus_idle(tegra->phy);
		if (!tegra_usb_phy_is_device_connected(tegra->phy))
			schedule_delayed_work(&tegra->work, 50);
	} else {
		tegra_ehci_restart(hcd);
	}

	return 0;
}

static void tegra_ehci_shutdown(struct usb_hcd *hcd)
{
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);

	/* ehci_shutdown touches the USB controller registers, make sure
	 * controller has clocks to it */
	if (!tegra->host_resumed)
		tegra_ehci_power_up(hcd);

	ehci_shutdown(hcd);

	/* we are ready to shut down, powerdown the phy */
	tegra_ehci_power_down(hcd);
}

static int tegra_ehci_setup(struct usb_hcd *hcd)
{
	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
	int retval;

	/* EHCI registers start at offset 0x100 */
	ehci->caps = hcd->regs + 0x100;
	ehci->regs = hcd->regs + 0x100 +
		HC_LENGTH(readl(&ehci->caps->hc_capbase));

	dbg_hcs_params(ehci, "reset");
	dbg_hcc_params(ehci, "reset");

	/* cache this readonly data; minimize chip reads */
	ehci->hcs_params = readl(&ehci->caps->hcs_params);

	/* switch to host mode */
	hcd->has_tt = 1;
	ehci_reset(ehci);

	retval = ehci_halt(ehci);
	if (retval)
		return retval;

	/* data structure init */
	retval = ehci_init(hcd);
	if (retval)
		return retval;

	ehci->sbrn = 0x20;

	ehci_port_power(ehci, 1);
	return retval;
}

#ifdef CONFIG_PM
static int tegra_ehci_bus_suspend(struct usb_hcd *hcd)
{
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);
	int error_status = 0;

	error_status = ehci_bus_suspend(hcd);
	if (!error_status && tegra->power_down_on_bus_suspend) {
		tegra_usb_suspend(hcd);
		tegra->bus_suspended = 1;
	}
	return error_status;
}

static int tegra_ehci_bus_resume(struct usb_hcd *hcd)
{
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(hcd->self.controller);

	if (tegra->bus_suspended && tegra->power_down_on_bus_suspend) {
		tegra_usb_resume(hcd);
		tegra->bus_suspended = 0;
	}

	tegra_usb_phy_preresume(tegra->phy);
	tegra->port_resuming = 1;
	return ehci_bus_resume(hcd);
}
#endif

struct temp_buffer {
	void *kmalloc_ptr;
	void *old_xfer_buffer;
	u8 data[0];
};

static void free_temp_buffer(struct urb *urb)
{
	enum dma_data_direction dir;
	struct temp_buffer *temp;

	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
		return;

	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;

	temp = container_of(urb->transfer_buffer, struct temp_buffer,
			    data);

	if (dir == DMA_FROM_DEVICE)
		memcpy(temp->old_xfer_buffer, temp->data,
		       urb->transfer_buffer_length);
	urb->transfer_buffer = temp->old_xfer_buffer;
	kfree(temp->kmalloc_ptr);

	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
}

static int alloc_temp_buffer(struct urb *urb, gfp_t mem_flags)
{
	enum dma_data_direction dir;
	struct temp_buffer *temp, *kmalloc_ptr;
	size_t kmalloc_size;

	if (urb->num_sgs || urb->sg ||
	    urb->transfer_buffer_length == 0 ||
	    !((uintptr_t)urb->transfer_buffer & (TEGRA_USB_DMA_ALIGN - 1)))
		return 0;

	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;

	/* Allocate a buffer with enough padding for alignment */
	kmalloc_size = urb->transfer_buffer_length +
		sizeof(struct temp_buffer) + TEGRA_USB_DMA_ALIGN - 1;

	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
	if (!kmalloc_ptr)
		return -ENOMEM;

	/* Position our struct temp_buffer such that data is aligned */
	temp = PTR_ALIGN(kmalloc_ptr + 1, TEGRA_USB_DMA_ALIGN) - 1;

	temp->kmalloc_ptr = kmalloc_ptr;
	temp->old_xfer_buffer = urb->transfer_buffer;
	if (dir == DMA_TO_DEVICE)
		memcpy(temp->data, urb->transfer_buffer,
		       urb->transfer_buffer_length);
	urb->transfer_buffer = temp->data;

	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;

	return 0;
}

static int tegra_ehci_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
				      gfp_t mem_flags)
{
	int ret;

	ret = alloc_temp_buffer(urb, mem_flags);
	if (ret)
		return ret;

	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
	if (ret)
		free_temp_buffer(urb);

	return ret;
}

static void tegra_ehci_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
{
	usb_hcd_unmap_urb_for_dma(hcd, urb);
	free_temp_buffer(urb);
}

static void tegra_hsic_connection_work(struct work_struct *work)
{
	struct tegra_ehci_hcd *tegra =
		container_of(work, struct tegra_ehci_hcd, work.work);
	if (tegra_usb_phy_is_device_connected(tegra->phy)) {
		cancel_delayed_work(&tegra->work);
		return;
	}
	schedule_delayed_work(&tegra->work, jiffies + msecs_to_jiffies(50));
	return;
}

#ifdef CONFIG_USB_EHCI_ONOFF_FEATURE
/* Stored ehci handle for hsic insatnce */
struct usb_hcd *ehci_handle;
int ehci_tegra_irq;

static ssize_t show_ehci_power(struct device *dev,
			struct device_attribute *attr,
			char *buf)
{
	return sprintf(buf, "EHCI Power %s\n", (ehci_handle) ? "on" : "off");
}

static ssize_t store_ehci_power(struct device *dev,
		struct device_attribute *attr,
		const char *buf, size_t count)
{
	int power_on;
	int retval;
	struct tegra_ehci_hcd *tegra = dev_get_drvdata(dev);
	struct usb_hcd *hcd = ehci_to_hcd(tegra->ehci);

	if (sscanf(buf, "%d", &power_on) != 1)
		return -EINVAL;

	if (power_on == 0 && ehci_handle != NULL) {
		usb_remove_hcd(hcd);
		tegra_ehci_power_down(hcd);
		ehci_handle = NULL;
	} else if (power_on == 1) {
		if (ehci_handle)
			usb_remove_hcd(hcd);
		tegra_ehci_power_up(hcd);
		retval = usb_add_hcd(hcd, ehci_tegra_irq,
					IRQF_DISABLED | IRQF_SHARED);
		if (retval < 0)
			printk(KERN_ERR "power_on error\n");
		ehci_handle = hcd;
	}

	return count;
}

static DEVICE_ATTR(ehci_power, S_IRUSR | S_IRGRP | S_IWUSR | S_IWGRP,
		show_ehci_power, store_ehci_power);

static inline int create_ehci_sys_file(struct ehci_hcd *ehci)
{
	return device_create_file(ehci_to_hcd(ehci)->self.controller,
							&dev_attr_ehci_power);
}

static inline void remove_ehci_sys_file(struct ehci_hcd *ehci)
{
	device_remove_file(ehci_to_hcd(ehci)->self.controller,
						&dev_attr_ehci_power);
}

static int ehci_tegra_wait_register(void __iomem *reg, u32 mask, u32 result)
{
	unsigned long timeout = 50000;

	do {
		if ((readl(reg) & mask) == result)
			return 0;
		udelay(1);
		timeout--;
	} while (timeout);
	return -1;
}


void tegra_ehci_recover_rx_error(void)
{
	struct ehci_hcd *ehci;
	unsigned long val;
	struct usb_hcd *hcd = ehci_handle;

	if (hcd) {
		ehci  = hcd_to_ehci(ehci_handle);
		pr_info("{ RX_ERR_HANDLING_START \n");
		/* (0) set CLK_RST_..._LVL2_CLK_GATE_OVRB_0  USB2_CLK_OVR_ON = 1 */
		val = readl((IO_ADDRESS(TEGRA_CLK_RESET_BASE) + TEGRA_LVL2_CLK_GATE_OVRB));
		val |= TEGRA_USB2_CLK_OVR_ON;
		writel(val, (IO_ADDRESS(TEGRA_CLK_RESET_BASE) + TEGRA_LVL2_CLK_GATE_OVRB));
		/* (1) set PORTSC SUSP = 1 */
		val = ehci_readl(ehci, &ehci->regs->port_status[0]);
		ehci_writel(ehci, val | PORT_SUSPEND, &ehci->regs->port_status[0]);
		/* (2) wait until PORTSC SUSP = 1 */
		if (handshake(ehci, &ehci->regs->port_status[0], PORT_SUSPEND,
							PORT_SUSPEND, 5000)) {
			pr_err("%s: timeout waiting for PORT_SUSPEND = 1\n", __func__);
			return;
		}
		/* (3) set PORTSC PHCD = 1 */
		val = ehci_readl(ehci, &ehci->regs->port_status[0]);
		ehci_writel(ehci, val | TEGRA_USB_PORTSC_PHCD, &ehci->regs->port_status[0]);
		/* (4) wait until SUSP_CTRL PHY_VALID = 0 */
		if (ehci_tegra_wait_register(hcd->regs + TEGRA_USB_SUSP_CTRL_OFFSET,
				TEGRA_USB_PHY_CLK_VALID, 0) < 0) {
			pr_err("%s: timeout waiting for TEGRA_USB_PHY_CLK_VALID = 0\n", __func__);
			return;
		}
		/* (5) set SUSP_CTRL SUSP_CLR = 1 */
		val = readl(hcd->regs + TEGRA_USB_SUSP_CTRL_OFFSET);
		writel((val | TEGRA_USB_SUSP_CLR),
			(hcd->regs + TEGRA_USB_SUSP_CTRL_OFFSET));
		/* (6) set SUSP_CTRL SUSP_CLR = 0 */
		val = readl(hcd->regs + TEGRA_USB_SUSP_CTRL_OFFSET);
		val &= ~(TEGRA_USB_SUSP_CLR);
		writel(val, (hcd->regs + TEGRA_USB_SUSP_CTRL_OFFSET));
		/* (7) wait until SUSP_CTRL PHY_VALID = 1 */
		if (ehci_tegra_wait_register(hcd->regs + TEGRA_USB_SUSP_CTRL_OFFSET,
				TEGRA_USB_PHY_CLK_VALID, TEGRA_USB_PHY_CLK_VALID) < 0) {
			pr_err("%s: timeout waiting for TEGRA_USB_PHY_CLK_VALID = 1\n", __func__);
			return;
		}
		/* (8) set PORTSC SRT = 1 */
		val = ehci_readl(ehci, &ehci->regs->port_status[0]);
		ehci_writel(ehci, val | TEGRA_USB_SRT, &ehci->regs->port_status[0]);
		/* (9) set PORTSC FPR = 1 */
		val = ehci_readl(ehci, &ehci->regs->port_status[0]);
		ehci_writel(ehci, val | PORT_RESUME, &ehci->regs->port_status[0]);
		/* (10) wait until PORTSC FPR = 0 */
		if (handshake(ehci, &ehci->regs->port_status[0], PORT_RESUME,
								0, 5000)) {
			pr_err("%s: timeout waiting for PORT_RESUME = 1\n", __func__);
			return;
		}
		/* (11) set PORTSC SRT = 0 */
		val = ehci_readl(ehci, &ehci->regs->port_status[0]);
		val &= ~(TEGRA_USB_SRT);
		ehci_writel(ehci, val, &ehci->regs->port_status[0]);
		pr_info("} \n");
	}
}

EXPORT_SYMBOL(tegra_ehci_recover_rx_error);

#endif

static const struct hc_driver tegra_ehci_hc_driver = {
	.description		= hcd_name,
	.product_desc		= "Tegra EHCI Host Controller",
	.hcd_priv_size		= sizeof(struct ehci_hcd),

	.flags			= HCD_USB2 | HCD_MEMORY,

	.reset			= tegra_ehci_setup,
	.irq			= ehci_irq,

	.start			= ehci_run,
	.stop			= ehci_stop,
	.shutdown		= tegra_ehci_shutdown,
	.urb_enqueue		= ehci_urb_enqueue,
	.urb_dequeue		= ehci_urb_dequeue,
	.map_urb_for_dma	= tegra_ehci_map_urb_for_dma,
	.unmap_urb_for_dma	= tegra_ehci_unmap_urb_for_dma,
	.endpoint_disable	= ehci_endpoint_disable,
	.endpoint_reset		= ehci_endpoint_reset,
	.get_frame_number	= ehci_get_frame,
	.hub_status_data	= ehci_hub_status_data,
	.hub_control		= tegra_ehci_hub_control,
	.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
#ifdef CONFIG_PM
	.bus_suspend		= tegra_ehci_bus_suspend,
	.bus_resume		= tegra_ehci_bus_resume,
#endif
	.relinquish_port	= ehci_relinquish_port,
	.port_handed_over	= ehci_port_handed_over,
};

static int tegra_ehci_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct usb_hcd *hcd;
	struct tegra_ehci_hcd *tegra;
	struct tegra_ehci_platform_data *pdata;
	int err = 0;
	int irq;
	int instance = pdev->id;

	pdata = pdev->dev.platform_data;
	if (!pdata) {
		dev_err(&pdev->dev, "Platform data missing\n");
		return -EINVAL;
	}

	tegra = kzalloc(sizeof(struct tegra_ehci_hcd), GFP_KERNEL);
	if (!tegra)
		return -ENOMEM;

	hcd = usb_create_hcd(&tegra_ehci_hc_driver, &pdev->dev,
					dev_name(&pdev->dev));
	if (!hcd) {
		dev_err(&pdev->dev, "Unable to create HCD\n");
		err = -ENOMEM;
		goto fail_hcd;
	}

	platform_set_drvdata(pdev, tegra);

	tegra->clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(tegra->clk)) {
		dev_err(&pdev->dev, "Can't get ehci clock\n");
		err = PTR_ERR(tegra->clk);
		goto fail_clk;
	}

	err = clk_enable(tegra->clk);
	if (err)
		goto fail_clken;

	tegra->emc_clk = clk_get(&pdev->dev, "emc");
	if (IS_ERR(tegra->emc_clk)) {
		dev_err(&pdev->dev, "Can't get emc clock\n");
		err = PTR_ERR(tegra->emc_clk);
		goto fail_emc_clk;
	}

	clk_enable(tegra->emc_clk);
	clk_set_rate(tegra->emc_clk, 400000000);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(&pdev->dev, "Failed to get I/O memory\n");
		err = -ENXIO;
		goto fail_io;
	}
	hcd->rsrc_start = res->start;
	hcd->rsrc_len = resource_size(res);
	hcd->regs = ioremap(res->start, resource_size(res));
	if (!hcd->regs) {
		dev_err(&pdev->dev, "Failed to remap I/O memory\n");
		err = -ENOMEM;
		goto fail_io;
	}

	INIT_DELAYED_WORK(&tegra->work, tegra_hsic_connection_work);

	tegra->phy = tegra_usb_phy_open(instance, hcd->regs, pdata->phy_config,
						TEGRA_USB_PHY_MODE_HOST);
	if (IS_ERR(tegra->phy)) {
		dev_err(&pdev->dev, "Failed to open USB phy\n");
		err = -ENXIO;
		goto fail_phy;
	}

	err = tegra_usb_phy_power_on(tegra->phy);
	if (err) {
		dev_err(&pdev->dev, "Failed to power on the phy\n");
		goto fail;
	}

	tegra->host_resumed = 1;
	tegra->power_down_on_bus_suspend = pdata->power_down_on_bus_suspend;
	tegra->ehci = hcd_to_ehci(hcd);

	irq = platform_get_irq(pdev, 0);
	if (!irq) {
		dev_err(&pdev->dev, "Failed to get IRQ\n");
		err = -ENODEV;
		goto fail;
	}
	set_irq_flags(irq, IRQF_VALID);

#ifdef CONFIG_USB_EHCI_ONOFF_FEATURE
	if (instance == 1) {
		ehci_tegra_irq = irq;
		create_ehci_sys_file(tegra->ehci);
	}
#endif

#ifdef CONFIG_USB_OTG_UTILS
	if (pdata->operating_mode == TEGRA_USB_OTG) {
		tegra->transceiver = otg_get_transceiver();
		if (tegra->transceiver)
			otg_set_host(tegra->transceiver, &hcd->self);
	}
#endif

	err = usb_add_hcd(hcd, irq, IRQF_DISABLED | IRQF_SHARED);
	if (err) {
		dev_err(&pdev->dev, "Failed to add USB HCD\n");
		goto fail;
	}

#ifdef CONFIG_USB_EHCI_ONOFF_FEATURE
	if (instance == 1)
		ehci_handle = hcd;
#endif
	return err;

fail:
#ifdef CONFIG_USB_OTG_UTILS
	if (tegra->transceiver) {
		otg_set_host(tegra->transceiver, NULL);
		otg_put_transceiver(tegra->transceiver);
	}
#endif
	tegra_usb_phy_close(tegra->phy);
fail_phy:
	iounmap(hcd->regs);
fail_io:
	clk_disable(tegra->emc_clk);
	clk_put(tegra->emc_clk);
fail_emc_clk:
	clk_disable(tegra->clk);
fail_clken:
	clk_put(tegra->clk);
fail_clk:
	usb_put_hcd(hcd);
fail_hcd:
	kfree(tegra);
	return err;
}

#ifdef CONFIG_PM
static int tegra_ehci_resume(struct platform_device *pdev)
{
	struct tegra_ehci_hcd *tegra = platform_get_drvdata(pdev);
	struct usb_hcd *hcd = ehci_to_hcd(tegra->ehci);

	if ((tegra->bus_suspended) && (tegra->power_down_on_bus_suspend))
		return 0;

	return tegra_usb_resume(hcd);
}

static int tegra_ehci_suspend(struct platform_device *pdev, pm_message_t state)
{
	struct tegra_ehci_hcd *tegra = platform_get_drvdata(pdev);
	struct usb_hcd *hcd = ehci_to_hcd(tegra->ehci);

	if ((tegra->bus_suspended) && (tegra->power_down_on_bus_suspend))
		return 0;

	if (time_before(jiffies, tegra->ehci->next_statechange))
		msleep(10);

	return tegra_usb_suspend(hcd);
}
#endif

static int tegra_ehci_remove(struct platform_device *pdev)
{
	struct tegra_ehci_hcd *tegra = platform_get_drvdata(pdev);
	struct usb_hcd *hcd = ehci_to_hcd(tegra->ehci);

	if (tegra == NULL || hcd == NULL)
		return -EINVAL;

#ifdef CONFIG_USB_OTG_UTILS
	if (tegra->transceiver) {
		otg_set_host(tegra->transceiver, NULL);
		otg_put_transceiver(tegra->transceiver);
	}
#endif

#ifdef CONFIG_USB_EHCI_ONOFF_FEATURE
	if (tegra->phy->instance == 1) {
		remove_ehci_sys_file(hcd_to_ehci(hcd));
		ehci_handle = NULL;
	}
#endif

	/* Turn Off Interrupts */
	ehci_writel(tegra->ehci, 0, &tegra->ehci->regs->intr_enable);
	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
	usb_remove_hcd(hcd);
	usb_put_hcd(hcd);
	cancel_delayed_work(&tegra->work);
	tegra_usb_phy_power_off(tegra->phy);
	tegra_usb_phy_close(tegra->phy);
	iounmap(hcd->regs);

	clk_disable(tegra->clk);
	clk_put(tegra->clk);

	clk_disable(tegra->emc_clk);
	clk_put(tegra->emc_clk);

	kfree(tegra);
	return 0;
}

static void tegra_ehci_hcd_shutdown(struct platform_device *pdev)
{
	struct tegra_ehci_hcd *tegra = platform_get_drvdata(pdev);
	struct usb_hcd *hcd = ehci_to_hcd(tegra->ehci);

	if (hcd->driver->shutdown)
		hcd->driver->shutdown(hcd);
}

static struct platform_driver tegra_ehci_driver = {
	.probe		= tegra_ehci_probe,
	.remove		= tegra_ehci_remove,
#ifdef CONFIG_PM
	.suspend	= tegra_ehci_suspend,
	.resume		= tegra_ehci_resume,
#endif
	.shutdown	= tegra_ehci_hcd_shutdown,
	.driver		= {
		.name	= "tegra-ehci",
	}
};