root/drivers/usb/host/ehci-mv.c
// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2011 Marvell International Ltd. All rights reserved.
 * Author: Chao Xie <chao.xie@marvell.com>
 *        Neil Zhang <zhangwm@marvell.com>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/usb/otg.h>
#include <linux/usb/of.h>
#include <linux/platform_data/mv_usb.h>
#include <linux/io.h>

#include <linux/usb/hcd.h>

#include "ehci.h"

/* registers */
#define U2x_CAPREGS_OFFSET       0x100

#define CAPLENGTH_MASK         (0xff)

#define hcd_to_ehci_hcd_mv(h) ((struct ehci_hcd_mv *)hcd_to_ehci(h)->priv)

struct ehci_hcd_mv {
        /* Which mode does this ehci running OTG/Host ? */
        int mode;

        void __iomem *base;
        void __iomem *cap_regs;
        void __iomem *op_regs;

        struct usb_phy *otg;
        struct clk *clk;

        struct phy *phy;

        int (*set_vbus)(unsigned int vbus);
};

static int mv_ehci_enable(struct ehci_hcd_mv *ehci_mv)
{
        int retval;

        retval = clk_prepare_enable(ehci_mv->clk);
        if (retval)
                return retval;

        retval = phy_init(ehci_mv->phy);
        if (retval)
                clk_disable_unprepare(ehci_mv->clk);

        return retval;
}

static void mv_ehci_disable(struct ehci_hcd_mv *ehci_mv)
{
        phy_exit(ehci_mv->phy);
        clk_disable_unprepare(ehci_mv->clk);
}

static int mv_ehci_reset(struct usb_hcd *hcd)
{
        struct device *dev = hcd->self.controller;
        struct ehci_hcd_mv *ehci_mv = hcd_to_ehci_hcd_mv(hcd);
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        u32 status;
        int retval;

        if (ehci_mv == NULL) {
                dev_err(dev, "Can not find private ehci data\n");
                return -ENODEV;
        }

        hcd->has_tt = 1;

        retval = ehci_setup(hcd);
        if (retval)
                dev_err(dev, "ehci_setup failed %d\n", retval);

        if (of_usb_get_phy_mode(dev->of_node) == USBPHY_INTERFACE_MODE_HSIC) {
                status = ehci_readl(ehci, &ehci->regs->port_status[0]);
                status |= PORT_TEST_FORCE;
                ehci_writel(ehci, status, &ehci->regs->port_status[0]);
                status &= ~PORT_TEST_FORCE;
                ehci_writel(ehci, status, &ehci->regs->port_status[0]);
        }

        return retval;
}

static struct hc_driver __read_mostly ehci_platform_hc_driver;

static const struct ehci_driver_overrides platform_overrides __initconst = {
        .reset =                mv_ehci_reset,
        .extra_priv_size =      sizeof(struct ehci_hcd_mv),
};

static int mv_ehci_probe(struct platform_device *pdev)
{
        struct mv_usb_platform_data *pdata = dev_get_platdata(&pdev->dev);
        struct usb_hcd *hcd;
        struct ehci_hcd *ehci;
        struct ehci_hcd_mv *ehci_mv;
        struct resource *r;
        int retval;
        u32 offset;
        u32 status;

        if (usb_disabled())
                return -ENODEV;

        hcd = usb_create_hcd(&ehci_platform_hc_driver, &pdev->dev, dev_name(&pdev->dev));
        if (!hcd)
                return -ENOMEM;

        platform_set_drvdata(pdev, hcd);
        ehci_mv = hcd_to_ehci_hcd_mv(hcd);

        ehci_mv->mode = MV_USB_MODE_HOST;
        if (pdata) {
                ehci_mv->mode = pdata->mode;
                ehci_mv->set_vbus = pdata->set_vbus;
        }

        ehci_mv->phy = devm_phy_optional_get(&pdev->dev, "usb");
        if (IS_ERR(ehci_mv->phy)) {
                retval = PTR_ERR(ehci_mv->phy);
                if (retval != -EPROBE_DEFER)
                        dev_err(&pdev->dev, "Failed to get phy.\n");
                goto err_put_hcd;
        }

        ehci_mv->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(ehci_mv->clk)) {
                dev_err(&pdev->dev, "error getting clock\n");
                retval = PTR_ERR(ehci_mv->clk);
                goto err_put_hcd;
        }

        ehci_mv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
        if (IS_ERR(ehci_mv->base)) {
                retval = PTR_ERR(ehci_mv->base);
                goto err_put_hcd;
        }

        retval = mv_ehci_enable(ehci_mv);
        if (retval) {
                dev_err(&pdev->dev, "init phy error %d\n", retval);
                goto err_put_hcd;
        }

        ehci_mv->cap_regs =
                (void __iomem *) ((unsigned long) ehci_mv->base + U2x_CAPREGS_OFFSET);
        offset = readl(ehci_mv->cap_regs) & CAPLENGTH_MASK;
        ehci_mv->op_regs =
                (void __iomem *) ((unsigned long) ehci_mv->cap_regs + offset);

        hcd->rsrc_start = r->start;
        hcd->rsrc_len = resource_size(r);
        hcd->regs = ehci_mv->op_regs;

        retval = platform_get_irq(pdev, 0);
        if (retval < 0)
                goto err_disable_clk;
        hcd->irq = retval;

        ehci = hcd_to_ehci(hcd);
        ehci->caps = (struct ehci_caps __iomem *) ehci_mv->cap_regs;

        if (ehci_mv->mode == MV_USB_MODE_OTG) {
                ehci_mv->otg = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
                if (IS_ERR(ehci_mv->otg)) {
                        retval = PTR_ERR(ehci_mv->otg);

                        if (retval == -ENXIO)
                                dev_info(&pdev->dev, "MV_USB_MODE_OTG "
                                                "must have CONFIG_USB_PHY enabled\n");
                        else
                                dev_err(&pdev->dev,
                                                "unable to find transceiver\n");
                        goto err_disable_clk;
                }

                retval = otg_set_host(ehci_mv->otg->otg, &hcd->self);
                if (retval < 0) {
                        dev_err(&pdev->dev,
                                "unable to register with transceiver\n");
                        retval = -ENODEV;
                        goto err_disable_clk;
                }
                /* otg will enable clock before use as host */
                mv_ehci_disable(ehci_mv);
        } else {
                if (ehci_mv->set_vbus)
                        ehci_mv->set_vbus(1);

                retval = usb_add_hcd(hcd, hcd->irq, IRQF_SHARED);
                if (retval) {
                        dev_err(&pdev->dev,
                                "failed to add hcd with err %d\n", retval);
                        goto err_set_vbus;
                }
                device_wakeup_enable(hcd->self.controller);
        }

        if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_HSIC) {
                status = ehci_readl(ehci, &ehci->regs->port_status[0]);
                /* These "reserved" bits actually enable HSIC mode. */
                status |= BIT(25);
                status &= ~GENMASK(31, 30);
                ehci_writel(ehci, status, &ehci->regs->port_status[0]);
        }

        dev_info(&pdev->dev,
                 "successful find EHCI device with regs 0x%p irq %d"
                 " working in %s mode\n", hcd->regs, hcd->irq,
                 ehci_mv->mode == MV_USB_MODE_OTG ? "OTG" : "Host");

        return 0;

err_set_vbus:
        if (ehci_mv->set_vbus)
                ehci_mv->set_vbus(0);
err_disable_clk:
        mv_ehci_disable(ehci_mv);
err_put_hcd:
        usb_put_hcd(hcd);

        return retval;
}

static void mv_ehci_remove(struct platform_device *pdev)
{
        struct usb_hcd *hcd = platform_get_drvdata(pdev);
        struct ehci_hcd_mv *ehci_mv = hcd_to_ehci_hcd_mv(hcd);

        if (hcd->rh_registered)
                usb_remove_hcd(hcd);

        if (!IS_ERR_OR_NULL(ehci_mv->otg))
                otg_set_host(ehci_mv->otg->otg, NULL);

        if (ehci_mv->mode == MV_USB_MODE_HOST) {
                if (ehci_mv->set_vbus)
                        ehci_mv->set_vbus(0);

                mv_ehci_disable(ehci_mv);
        }

        usb_put_hcd(hcd);
}

static const struct platform_device_id ehci_id_table[] = {
        {"pxa-u2oehci", 0},
        {"pxa-sph", 0},
        {},
};

static void mv_ehci_shutdown(struct platform_device *pdev)
{
        struct usb_hcd *hcd = platform_get_drvdata(pdev);

        if (!hcd->rh_registered)
                return;

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

static const struct of_device_id ehci_mv_dt_ids[] = {
        { .compatible = "marvell,pxau2o-ehci", },
        {},
};

static struct platform_driver ehci_mv_driver = {
        .probe = mv_ehci_probe,
        .remove = mv_ehci_remove,
        .shutdown = mv_ehci_shutdown,
        .driver = {
                .name = "mv-ehci",
                .bus = &platform_bus_type,
                .of_match_table = ehci_mv_dt_ids,
        },
        .id_table = ehci_id_table,
};

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

        ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
        return platform_driver_register(&ehci_mv_driver);
}
module_init(ehci_platform_init);

static void __exit ehci_platform_cleanup(void)
{
        platform_driver_unregister(&ehci_mv_driver);
}
module_exit(ehci_platform_cleanup);

MODULE_DESCRIPTION("Marvell EHCI driver");
MODULE_AUTHOR("Chao Xie <chao.xie@marvell.com>");
MODULE_AUTHOR("Neil Zhang <zhangwm@marvell.com>");
MODULE_ALIAS("mv-ehci");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(of, ehci_mv_dt_ids);