ohci-spear.c

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/*
* OHCI HCD (Host Controller Driver) for USB.
*
* Copyright (C) 2010 ST Microelectronics.
* Deepak Sikri<[email protected]>
*
* Based on various ohci-*.c drivers
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/

#include <linux/signal.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/of.h>

struct spear_ohci {
    struct ohci_hcd ohci;
    struct clk *clk;
};

#define to_spear_ohci(hcd)  (struct spear_ohci *)hcd_to_ohci(hcd)

static void spear_start_ohci(struct spear_ohci *ohci)
{
    clk_prepare_enable(ohci->clk);
}

static void spear_stop_ohci(struct spear_ohci *ohci)
{
    clk_disable_unprepare(ohci->clk);
}

static int __devinit ohci_spear_start(struct usb_hcd *hcd)
{
    struct ohci_hcd *ohci = hcd_to_ohci(hcd);
    int ret;

    ret = ohci_init(ohci);
    if (ret < 0)
        return ret;
    ohci->regs = hcd->regs;

    ret = ohci_run(ohci);
    if (ret < 0) {
        dev_err(hcd->self.controller, "can't start\n");
        ohci_stop(hcd);
        return ret;
    }

    create_debug_files(ohci);

#ifdef DEBUG
    ohci_dump(ohci, 1);
#endif
    return 0;
}

static const struct hc_driver ohci_spear_hc_driver = {
    .description        = hcd_name,
    .product_desc       = "SPEAr OHCI",
    .hcd_priv_size      = sizeof(struct spear_ohci),

    /* generic hardware linkage */
    .irq            = ohci_irq,
    .flags          = HCD_USB11 | HCD_MEMORY,

    /* basic lifecycle operations */
    .start          = ohci_spear_start,
    .stop           = ohci_stop,
    .shutdown       = ohci_shutdown,
#ifdef  CONFIG_PM
    .bus_suspend        = ohci_bus_suspend,
    .bus_resume     = ohci_bus_resume,
#endif

    /* managing i/o requests and associated device resources */
    .urb_enqueue        = ohci_urb_enqueue,
    .urb_dequeue        = ohci_urb_dequeue,
    .endpoint_disable   = ohci_endpoint_disable,

    /* scheduling support */
    .get_frame_number   = ohci_get_frame,

    /* root hub support */
    .hub_status_data    = ohci_hub_status_data,
    .hub_control        = ohci_hub_control,

    .start_port_reset   = ohci_start_port_reset,
};

static u64 spear_ohci_dma_mask = DMA_BIT_MASK(32);

static int spear_ohci_hcd_drv_probe(struct platform_device *pdev)
{
    const struct hc_driver *driver = &ohci_spear_hc_driver;
    struct usb_hcd *hcd = NULL;
    struct clk *usbh_clk;
    struct spear_ohci *ohci_p;
    struct resource *res;
    int retval, irq;
    char clk_name[20] = "usbh_clk";
    static int instance = -1;

    irq = platform_get_irq(pdev, 0);
    if (irq < 0) {
        retval = irq;
        goto fail_irq_get;
    }

    /*
     * 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 (!pdev->dev.dma_mask)
        pdev->dev.dma_mask = &spear_ohci_dma_mask;

    /*
     * Increment the device instance, when probing via device-tree
     */
    if (pdev->id < 0)
        instance++;
    else
        instance = pdev->id;
    sprintf(clk_name, "usbh.%01d_clk", instance);

    usbh_clk = clk_get(NULL, clk_name);
    if (IS_ERR(usbh_clk)) {
        dev_err(&pdev->dev, "Error getting interface clock\n");
        retval = PTR_ERR(usbh_clk);
        goto fail_get_usbh_clk;
    }

    hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
    if (!hcd) {
        retval = -ENOMEM;
        goto fail_create_hcd;
    }

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!res) {
        retval = -ENODEV;
        goto fail_request_resource;
    }

    hcd->rsrc_start = pdev->resource[0].start;
    hcd->rsrc_len = resource_size(res);
    if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
        dev_dbg(&pdev->dev, "request_mem_region failed\n");
        retval = -EBUSY;
        goto fail_request_resource;
    }

    hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
    if (!hcd->regs) {
        dev_dbg(&pdev->dev, "ioremap failed\n");
        retval = -ENOMEM;
        goto fail_ioremap;
    }

    ohci_p = (struct spear_ohci *)hcd_to_ohci(hcd);
    ohci_p->clk = usbh_clk;
    spear_start_ohci(ohci_p);
    ohci_hcd_init(hcd_to_ohci(hcd));

    retval = usb_add_hcd(hcd, platform_get_irq(pdev, 0), 0);
    if (retval == 0)
        return retval;

    spear_stop_ohci(ohci_p);
    iounmap(hcd->regs);
fail_ioremap:
    release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
fail_request_resource:
    usb_put_hcd(hcd);
fail_create_hcd:
    clk_put(usbh_clk);
fail_get_usbh_clk:
fail_irq_get:
    dev_err(&pdev->dev, "init fail, %d\n", retval);

    return retval;
}

static int spear_ohci_hcd_drv_remove(struct platform_device *pdev)
{
    struct usb_hcd *hcd = platform_get_drvdata(pdev);
    struct spear_ohci *ohci_p = to_spear_ohci(hcd);

    usb_remove_hcd(hcd);
    if (ohci_p->clk)
        spear_stop_ohci(ohci_p);

    iounmap(hcd->regs);
    release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
    usb_put_hcd(hcd);

    if (ohci_p->clk)
        clk_put(ohci_p->clk);
    platform_set_drvdata(pdev, NULL);
    return 0;
}

#if defined(CONFIG_PM)
static int spear_ohci_hcd_drv_suspend(struct platform_device *dev,
        pm_message_t message)
{
    struct usb_hcd *hcd = platform_get_drvdata(dev);
    struct ohci_hcd *ohci = hcd_to_ohci(hcd);
    struct spear_ohci *ohci_p = to_spear_ohci(hcd);

    if (time_before(jiffies, ohci->next_statechange))
        msleep(5);
    ohci->next_statechange = jiffies;

    spear_stop_ohci(ohci_p);
    return 0;
}

static int spear_ohci_hcd_drv_resume(struct platform_device *dev)
{
    struct usb_hcd *hcd = platform_get_drvdata(dev);
    struct ohci_hcd *ohci = hcd_to_ohci(hcd);
    struct spear_ohci *ohci_p = to_spear_ohci(hcd);

    if (time_before(jiffies, ohci->next_statechange))
        msleep(5);
    ohci->next_statechange = jiffies;

    spear_start_ohci(ohci_p);
    ohci_finish_controller_resume(hcd);
    return 0;
}
#endif

static struct of_device_id spear_ohci_id_table[] __devinitdata = {
    { .compatible = "st,spear600-ohci", },
    { },
};

/* Driver definition to register with the platform bus */
static struct platform_driver spear_ohci_hcd_driver = {
    .probe =    spear_ohci_hcd_drv_probe,
    .remove =   spear_ohci_hcd_drv_remove,
#ifdef CONFIG_PM
    .suspend =  spear_ohci_hcd_drv_suspend,
    .resume =   spear_ohci_hcd_drv_resume,
#endif
    .driver = {
        .owner = THIS_MODULE,
        .name = "spear-ohci",
        .of_match_table = of_match_ptr(spear_ohci_id_table),
    },
};

MODULE_ALIAS("platform:spear-ohci");