ehci-ppc-of.c

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/*
 * EHCI HCD (Host Controller Driver) for USB.
 *
 * Bus Glue for PPC On-Chip EHCI driver on the of_platform bus
 * Tested on AMCC PPC 440EPx
 *
 * Valentine Barshak <[email protected]>
 *
 * Based on "ehci-ppc-soc.c" by Stefan Roese <[email protected]>
 * and "ohci-ppc-of.c" by Sylvain Munaut <[email protected]>
 *
 * This file is licenced under the GPL.
 */

#include <linux/signal.h>

#include <linux/of.h>
#include <linux/of_platform.h>


static const struct hc_driver ehci_ppc_of_hc_driver = {
    .description        = hcd_name,
    .product_desc       = "OF EHCI",
    .hcd_priv_size      = sizeof(struct ehci_hcd),

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

    /*
     * basic lifecycle operations
     */
    .reset          = ehci_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,
#ifdef  CONFIG_PM
    .bus_suspend        = ehci_bus_suspend,
    .bus_resume     = ehci_bus_resume,
#endif
    .relinquish_port    = ehci_relinquish_port,
    .port_handed_over   = ehci_port_handed_over,

    .clear_tt_buffer_complete   = ehci_clear_tt_buffer_complete,
};


/*
 * 440EPx Errata USBH_3
 * Fix: Enable Break Memory Transfer (BMT) in INSNREG3
 */
#define PPC440EPX_EHCI0_INSREG_BMT  (0x1 << 0)
static int __devinit
ppc44x_enable_bmt(struct device_node *dn)
{
    __iomem u32 *insreg_virt;

    insreg_virt = of_iomap(dn, 1);
    if (!insreg_virt)
        return  -EINVAL;

    out_be32(insreg_virt + 3, PPC440EPX_EHCI0_INSREG_BMT);

    iounmap(insreg_virt);
    return 0;
}


static int __devinit ehci_hcd_ppc_of_probe(struct platform_device *op)
{
    struct device_node *dn = op->dev.of_node;
    struct usb_hcd *hcd;
    struct ehci_hcd *ehci = NULL;
    struct resource res;
    int irq;
    int rv;

    struct device_node *np;

    if (usb_disabled())
        return -ENODEV;

    dev_dbg(&op->dev, "initializing PPC-OF USB Controller\n");

    rv = of_address_to_resource(dn, 0, &res);
    if (rv)
        return rv;

    hcd = usb_create_hcd(&ehci_ppc_of_hc_driver, &op->dev, "PPC-OF USB");
    if (!hcd)
        return -ENOMEM;

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

    irq = irq_of_parse_and_map(dn, 0);
    if (irq == NO_IRQ) {
        printk(KERN_ERR "%s: irq_of_parse_and_map failed\n", __FILE__);
        rv = -EBUSY;
        goto err_irq;
    }

    hcd->regs = devm_request_and_ioremap(&op->dev, &res);
    if (!hcd->regs) {
        pr_err("%s: devm_request_and_ioremap failed\n", __FILE__);
        rv = -ENOMEM;
        goto err_ioremap;
    }

    ehci = hcd_to_ehci(hcd);
    np = of_find_compatible_node(NULL, NULL, "ibm,usb-ohci-440epx");
    if (np != NULL) {
        /* claim we really affected by usb23 erratum */
        if (!of_address_to_resource(np, 0, &res))
            ehci->ohci_hcctrl_reg =
                devm_ioremap(&op->dev,
                         res.start + OHCI_HCCTRL_OFFSET,
                         OHCI_HCCTRL_LEN);
        else
            pr_debug("%s: no ohci offset in fdt\n", __FILE__);
        if (!ehci->ohci_hcctrl_reg) {
            pr_debug("%s: ioremap for ohci hcctrl failed\n", __FILE__);
        } else {
            ehci->has_amcc_usb23 = 1;
        }
    }

    if (of_get_property(dn, "big-endian", NULL)) {
        ehci->big_endian_mmio = 1;
        ehci->big_endian_desc = 1;
    }
    if (of_get_property(dn, "big-endian-regs", NULL))
        ehci->big_endian_mmio = 1;
    if (of_get_property(dn, "big-endian-desc", NULL))
        ehci->big_endian_desc = 1;

    ehci->caps = hcd->regs;

    if (of_device_is_compatible(dn, "ibm,usb-ehci-440epx")) {
        rv = ppc44x_enable_bmt(dn);
        ehci_dbg(ehci, "Break Memory Transfer (BMT) is %senabled!\n",
                rv ? "NOT ": "");
    }

    rv = usb_add_hcd(hcd, irq, 0);
    if (rv)
        goto err_ioremap;

    return 0;

err_ioremap:
    irq_dispose_mapping(irq);
err_irq:
    usb_put_hcd(hcd);

    return rv;
}


static int ehci_hcd_ppc_of_remove(struct platform_device *op)
{
    struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
    struct ehci_hcd *ehci = hcd_to_ehci(hcd);

    struct device_node *np;
    struct resource res;

    dev_set_drvdata(&op->dev, NULL);

    dev_dbg(&op->dev, "stopping PPC-OF USB Controller\n");

    usb_remove_hcd(hcd);

    irq_dispose_mapping(hcd->irq);

    /* use request_mem_region to test if the ohci driver is loaded.  if so
     * ensure the ohci core is operational.
     */
    if (ehci->has_amcc_usb23) {
        np = of_find_compatible_node(NULL, NULL, "ibm,usb-ohci-440epx");
        if (np != NULL) {
            if (!of_address_to_resource(np, 0, &res))
                if (!request_mem_region(res.start,
                                0x4, hcd_name))
                    set_ohci_hcfs(ehci, 1);
                else
                    release_mem_region(res.start, 0x4);
            else
                pr_debug("%s: no ohci offset in fdt\n", __FILE__);
            of_node_put(np);
        }
    }
    usb_put_hcd(hcd);

    return 0;
}


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

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


static const struct of_device_id ehci_hcd_ppc_of_match[] = {
    {
        .compatible = "usb-ehci",
    },
    {},
};
MODULE_DEVICE_TABLE(of, ehci_hcd_ppc_of_match);


static struct platform_driver ehci_hcd_ppc_of_driver = {
    .probe      = ehci_hcd_ppc_of_probe,
    .remove     = ehci_hcd_ppc_of_remove,
    .shutdown   = ehci_hcd_ppc_of_shutdown,
    .driver = {
        .name = "ppc-of-ehci",
        .owner = THIS_MODULE,
        .of_match_table = ehci_hcd_ppc_of_match,
    },
};