/*
 * ehci-omap.c - driver for USBHOST on OMAP3/4 processors
 *
 * Bus Glue for the EHCI controllers in OMAP3/4
 * Tested on several OMAP3 boards, and OMAP4 Pandaboard
 *
 * Copyright (C) 2007-2013 Texas Instruments, Inc.
 *      Author: Vikram Pandita <vikram.pandita@ti.com>
 *      Author: Anand Gadiyar <gadiyar@ti.com>
 *      Author: Keshava Munegowda <keshava_mgowda@ti.com>
 *      Author: Roger Quadros <rogerq@ti.com>
 *
 * Copyright (C) 2009 Nokia Corporation
 *      Contact: Felipe Balbi <felipe.balbi@nokia.com>
 *
 * Based on "ehci-fsl.c" and "ehci-au1xxx.c" ehci glue layers
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/usb/ulpi.h>
#include <linux/pm_runtime.h>
#include <linux/gpio.h>
#include <linux/clk.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/of.h>
#include <linux/dma-mapping.h>

#include "ehci.h"

#include <linux/platform_data/usb-omap.h>

/* EHCI Register Set */
#define EHCI_INSNREG04                                  (0xA0)
#define EHCI_INSNREG04_DISABLE_UNSUSPEND                (1 << 5)
#define EHCI_INSNREG05_ULPI                             (0xA4)
#define EHCI_INSNREG05_ULPI_CONTROL_SHIFT               31
#define EHCI_INSNREG05_ULPI_PORTSEL_SHIFT               24
#define EHCI_INSNREG05_ULPI_OPSEL_SHIFT                 22
#define EHCI_INSNREG05_ULPI_REGADD_SHIFT                16
#define EHCI_INSNREG05_ULPI_EXTREGADD_SHIFT             8
#define EHCI_INSNREG05_ULPI_WRDATA_SHIFT                0

#define DRIVER_DESC "OMAP-EHCI Host Controller driver"

static const char hcd_name[] = "ehci-omap";

/*-------------------------------------------------------------------------*/

struct omap_hcd {
        struct usb_phy *phy[OMAP3_HS_USB_PORTS]; /* one PHY for each port */
        int nports;
};

static inline void ehci_write(void __iomem *base, u32 reg, u32 val)
{
        __raw_writel(val, base + reg);
}

static inline u32 ehci_read(void __iomem *base, u32 reg)
{
        return __raw_readl(base + reg);
}

/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */

static struct hc_driver __read_mostly ehci_omap_hc_driver;

static const struct ehci_driver_overrides ehci_omap_overrides __initdata = {
        .extra_priv_size = sizeof(struct omap_hcd),
};

/**
 * ehci_hcd_omap_probe - initialize TI-based HCDs
 *
 * Allocates basic resources for this USB host controller, and
 * then invokes the start() method for the HCD associated with it
 * through the hotplug entry's driver_data.
 */
static int ehci_hcd_omap_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct usbhs_omap_platform_data *pdata = dev->platform_data;
        struct resource *res;
        struct usb_hcd  *hcd;
        void __iomem *regs;
        int ret = -ENODEV;
        int irq;
        int i;
        struct omap_hcd *omap;

        if (usb_disabled())
                return -ENODEV;

        if (!dev->parent) {
                dev_err(dev, "Missing parent device\n");
                return -ENODEV;
        }

        /* For DT boot, get platform data from parent. i.e. usbhshost */
        if (dev->of_node) {
                pdata = dev->parent->platform_data;
                dev->platform_data = pdata;
        }

        if (!pdata) {
                dev_err(dev, "Missing platform data\n");
                return -ENODEV;
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
                dev_err(dev, "EHCI irq failed\n");
                return -ENODEV;
        }

        res =  platform_get_resource(pdev, IORESOURCE_MEM, 0);
        regs = devm_ioremap_resource(dev, res);
        if (IS_ERR(regs))
                return PTR_ERR(regs);

        /*
         * Right now device-tree probed devices don't get dma_mask set.
         * Since shared usb code relies on it, set it here for now.
         * Once we have dma capability bindings this can go away.
         */
        if (!dev->dma_mask)
                dev->dma_mask = &dev->coherent_dma_mask;
        if (!dev->coherent_dma_mask)
                dev->coherent_dma_mask = DMA_BIT_MASK(32);

        hcd = usb_create_hcd(&ehci_omap_hc_driver, dev,
                        dev_name(dev));
        if (!hcd) {
                dev_err(dev, "Failed to create HCD\n");
                return -ENOMEM;
        }

        hcd->rsrc_start = res->start;
        hcd->rsrc_len = resource_size(res);
        hcd->regs = regs;
        hcd_to_ehci(hcd)->caps = regs;

        omap = (struct omap_hcd *)hcd_to_ehci(hcd)->priv;
        omap->nports = pdata->nports;

        platform_set_drvdata(pdev, hcd);

        /* get the PHY devices if needed */
        for (i = 0 ; i < omap->nports ; i++) {
                struct usb_phy *phy;

                /* get the PHY device */
                if (dev->of_node)
                        phy = devm_usb_get_phy_by_phandle(dev, "phys", i);
                else
                        phy = devm_usb_get_phy_dev(dev, i);
                if (IS_ERR(phy)) {
                        /* Don't bail out if PHY is not absolutely necessary */
                        if (pdata->port_mode[i] != OMAP_EHCI_PORT_MODE_PHY)
                                continue;

                        ret = PTR_ERR(phy);
                        dev_err(dev, "Can't get PHY device for port %d: %d\n",
                                        i, ret);
                        goto err_phy;
                }

                omap->phy[i] = phy;
        }

        pm_runtime_enable(dev);
        pm_runtime_get_sync(dev);

        /*
         * An undocumented "feature" in the OMAP3 EHCI controller,
         * causes suspended ports to be taken out of suspend when
         * the USBCMD.Run/Stop bit is cleared (for example when
         * we do ehci_bus_suspend).
         * This breaks suspend-resume if the root-hub is allowed
         * to suspend. Writing 1 to this undocumented register bit
         * disables this feature and restores normal behavior.
         */
        ehci_write(regs, EHCI_INSNREG04,
                                EHCI_INSNREG04_DISABLE_UNSUSPEND);

        ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
        if (ret) {
                dev_err(dev, "failed to add hcd with err %d\n", ret);
                goto err_pm_runtime;
        }

        /*
         * Bring PHYs out of reset.
         * Even though HSIC mode is a PHY-less mode, the reset
         * line exists between the chips and can be modelled
         * as a PHY device for reset control.
         */
        for (i = 0; i < omap->nports; i++) {
                if (!omap->phy[i])
                        continue;

                usb_phy_init(omap->phy[i]);
                /* bring PHY out of suspend */
                usb_phy_set_suspend(omap->phy[i], 0);
        }

        return 0;

err_pm_runtime:
        pm_runtime_put_sync(dev);

err_phy:
        for (i = 0; i < omap->nports; i++) {
                if (omap->phy[i])
                        usb_phy_shutdown(omap->phy[i]);
        }

        usb_put_hcd(hcd);

        return ret;
}


/**
 * ehci_hcd_omap_remove - shutdown processing for EHCI HCDs
 * @pdev: USB Host Controller being removed
 *
 * Reverses the effect of usb_ehci_hcd_omap_probe(), first invoking
 * the HCD's stop() method.  It is always called from a thread
 * context, normally "rmmod", "apmd", or something similar.
 */
static int ehci_hcd_omap_remove(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct usb_hcd *hcd = dev_get_drvdata(dev);
        struct omap_hcd *omap = (struct omap_hcd *)hcd_to_ehci(hcd)->priv;
        int i;

        usb_remove_hcd(hcd);

        for (i = 0; i < omap->nports; i++) {
                if (omap->phy[i])
                        usb_phy_shutdown(omap->phy[i]);
        }

        usb_put_hcd(hcd);
        pm_runtime_put_sync(dev);
        pm_runtime_disable(dev);

        return 0;
}

static void ehci_hcd_omap_shutdown(struct platform_device *pdev)
{
        struct usb_hcd *hcd = dev_get_drvdata(&pdev->dev);

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

static const struct of_device_id omap_ehci_dt_ids[] = {
        { .compatible = "ti,ehci-omap" },
        { }
};

MODULE_DEVICE_TABLE(of, omap_ehci_dt_ids);

static struct platform_driver ehci_hcd_omap_driver = {
        .probe                  = ehci_hcd_omap_probe,
        .remove                 = ehci_hcd_omap_remove,
        .shutdown               = ehci_hcd_omap_shutdown,
        /*.suspend              = ehci_hcd_omap_suspend, */
        /*.resume               = ehci_hcd_omap_resume, */
        .driver = {
                .name           = hcd_name,
                .of_match_table = of_match_ptr(omap_ehci_dt_ids),
        }
};

/*-------------------------------------------------------------------------*/

static int __init ehci_omap_init(void)
{
        if (usb_disabled())
                return -ENODEV;

        pr_info("%s: " DRIVER_DESC "\n", hcd_name);

        ehci_init_driver(&ehci_omap_hc_driver, &ehci_omap_overrides);
        return platform_driver_register(&ehci_hcd_omap_driver);
}
module_init(ehci_omap_init);

static void __exit ehci_omap_cleanup(void)
{
        platform_driver_unregister(&ehci_hcd_omap_driver);
}
module_exit(ehci_omap_cleanup);

MODULE_ALIAS("platform:ehci-omap");
MODULE_AUTHOR("Texas Instruments, Inc.");
MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");
MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");