ehci-mxc.c

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/*
 * Copyright (c) 2008 Sascha Hauer <[email protected]>, Pengutronix
 * Copyright (c) 2009 Daniel Mack <[email protected]>
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/usb/otg.h>
#include <linux/usb/ulpi.h>
#include <linux/slab.h>

#include <mach/hardware.h>
#include <linux/platform_data/usb-ehci-mxc.h>

#include <asm/mach-types.h>

#define ULPI_VIEWPORT_OFFSET    0x170

struct ehci_mxc_priv {
    struct clk *usbclk, *ahbclk, *phyclk;
    struct usb_hcd *hcd;
};

/* called during probe() after chip reset completes */
static int ehci_mxc_setup(struct usb_hcd *hcd)
{
    struct ehci_hcd *ehci = hcd_to_ehci(hcd);
    int retval;

    hcd->has_tt = 1;

    retval = ehci_setup(hcd);
    if (retval)
        return retval;

    ehci_port_power(ehci, 0);
    return 0;
}

static const struct hc_driver ehci_mxc_hc_driver = {
    .description = hcd_name,
    .product_desc = "Freescale On-Chip EHCI Host Controller",
    .hcd_priv_size = sizeof(struct ehci_hcd),

    /*
     * generic hardware linkage
     */
    .irq = ehci_irq,
    .flags = HCD_USB2 | HCD_MEMORY,

    /*
     * basic lifecycle operations
     */
    .reset = ehci_mxc_setup,
    .start = ehci_run,
    .stop = ehci_stop,
    .shutdown = ehci_shutdown,

    /*
     * managing i/o requests and associated device resources
     */
    .urb_enqueue = ehci_urb_enqueue,
    .urb_dequeue = ehci_urb_dequeue,
    .endpoint_disable = ehci_endpoint_disable,
    .endpoint_reset = ehci_endpoint_reset,

    /*
     * scheduling support
     */
    .get_frame_number = ehci_get_frame,

    /*
     * root hub support
     */
    .hub_status_data = ehci_hub_status_data,
    .hub_control = ehci_hub_control,
    .bus_suspend = ehci_bus_suspend,
    .bus_resume = ehci_bus_resume,
    .relinquish_port = ehci_relinquish_port,
    .port_handed_over = ehci_port_handed_over,

    .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
};

static int ehci_mxc_drv_probe(struct platform_device *pdev)
{
    struct mxc_usbh_platform_data *pdata = pdev->dev.platform_data;
    struct usb_hcd *hcd;
    struct resource *res;
    int irq, ret;
    unsigned int flags;
    struct ehci_mxc_priv *priv;
    struct device *dev = &pdev->dev;
    struct ehci_hcd *ehci;

    dev_info(&pdev->dev, "initializing i.MX USB Controller\n");

    if (!pdata) {
        dev_err(dev, "No platform data given, bailing out.\n");
        return -EINVAL;
    }

    irq = platform_get_irq(pdev, 0);

    hcd = usb_create_hcd(&ehci_mxc_hc_driver, dev, dev_name(dev));
    if (!hcd)
        return -ENOMEM;

    priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
    if (!priv) {
        ret = -ENOMEM;
        goto err_alloc;
    }

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!res) {
        dev_err(dev, "Found HC with no register addr. Check setup!\n");
        ret = -ENODEV;
        goto err_alloc;
    }

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

    hcd->regs = devm_request_and_ioremap(&pdev->dev, res);
    if (!hcd->regs) {
        dev_err(dev, "error mapping memory\n");
        ret = -EFAULT;
        goto err_alloc;
    }

    /* enable clocks */
    priv->usbclk = devm_clk_get(&pdev->dev, "ipg");
    if (IS_ERR(priv->usbclk)) {
        ret = PTR_ERR(priv->usbclk);
        goto err_alloc;
    }
    clk_prepare_enable(priv->usbclk);

    priv->ahbclk = devm_clk_get(&pdev->dev, "ahb");
    if (IS_ERR(priv->ahbclk)) {
        ret = PTR_ERR(priv->ahbclk);
        goto err_clk_ahb;
    }
    clk_prepare_enable(priv->ahbclk);

    /* "dr" device has its own clock on i.MX51 */
    priv->phyclk = devm_clk_get(&pdev->dev, "phy");
    if (IS_ERR(priv->phyclk))
        priv->phyclk = NULL;
    if (priv->phyclk)
        clk_prepare_enable(priv->phyclk);


    /* call platform specific init function */
    if (pdata->init) {
        ret = pdata->init(pdev);
        if (ret) {
            dev_err(dev, "platform init failed\n");
            goto err_init;
        }
        /* platforms need some time to settle changed IO settings */
        mdelay(10);
    }

    ehci = hcd_to_ehci(hcd);

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

    /* set up the PORTSCx register */
    ehci_writel(ehci, pdata->portsc, &ehci->regs->port_status[0]);

    /* is this really needed? */
    msleep(10);

    /* Initialize the transceiver */
    if (pdata->otg) {
        pdata->otg->io_priv = hcd->regs + ULPI_VIEWPORT_OFFSET;
        ret = usb_phy_init(pdata->otg);
        if (ret) {
            dev_err(dev, "unable to init transceiver, probably missing\n");
            ret = -ENODEV;
            goto err_add;
        }
        ret = otg_set_vbus(pdata->otg->otg, 1);
        if (ret) {
            dev_err(dev, "unable to enable vbus on transceiver\n");
            goto err_add;
        }
    }

    priv->hcd = hcd;
    platform_set_drvdata(pdev, priv);

    ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
    if (ret)
        goto err_add;

    if (pdata->otg) {
        /*
         * efikamx and efikasb have some hardware bug which is
         * preventing usb to work unless CHRGVBUS is set.
         * It's in violation of USB specs
         */
        if (machine_is_mx51_efikamx() || machine_is_mx51_efikasb()) {
            flags = usb_phy_io_read(pdata->otg,
                            ULPI_OTG_CTRL);
            flags |= ULPI_OTG_CTRL_CHRGVBUS;
            ret = usb_phy_io_write(pdata->otg, flags,
                            ULPI_OTG_CTRL);
            if (ret) {
                dev_err(dev, "unable to set CHRVBUS\n");
                goto err_add;
            }
        }
    }

    return 0;

err_add:
    if (pdata && pdata->exit)
        pdata->exit(pdev);
err_init:
    if (priv->phyclk)
        clk_disable_unprepare(priv->phyclk);

    clk_disable_unprepare(priv->ahbclk);
err_clk_ahb:
    clk_disable_unprepare(priv->usbclk);
err_alloc:
    usb_put_hcd(hcd);
    return ret;
}

static int __exit ehci_mxc_drv_remove(struct platform_device *pdev)
{
    struct mxc_usbh_platform_data *pdata = pdev->dev.platform_data;
    struct ehci_mxc_priv *priv = platform_get_drvdata(pdev);
    struct usb_hcd *hcd = priv->hcd;

    if (pdata && pdata->exit)
        pdata->exit(pdev);

    if (pdata->otg)
        usb_phy_shutdown(pdata->otg);

    usb_remove_hcd(hcd);
    usb_put_hcd(hcd);
    platform_set_drvdata(pdev, NULL);

    clk_disable_unprepare(priv->usbclk);
    clk_disable_unprepare(priv->ahbclk);

    if (priv->phyclk)
        clk_disable_unprepare(priv->phyclk);

    return 0;
}

static void ehci_mxc_drv_shutdown(struct platform_device *pdev)
{
    struct ehci_mxc_priv *priv = platform_get_drvdata(pdev);
    struct usb_hcd *hcd = priv->hcd;

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

MODULE_ALIAS("platform:mxc-ehci");

static struct platform_driver ehci_mxc_driver = {
    .probe = ehci_mxc_drv_probe,
    .remove = __exit_p(ehci_mxc_drv_remove),
    .shutdown = ehci_mxc_drv_shutdown,
    .driver = {
           .name = "mxc-ehci",
    },
};