/*
 * UHCI HCD (Host Controller Driver) for GRLIB GRUSBHC
 *
 * Copyright (c) 2011 Jan Andersson <jan@gaisler.com>
 *
 * This file is based on UHCI PCI HCD:
 * (C) Copyright 1999 Linus Torvalds
 * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
 * (C) Copyright 1999 Randy Dunlap
 * (C) Copyright 1999 Georg Acher, acher@in.tum.de
 * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
 * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
 * (C) Copyright 1999 Roman Weissgaerber, weissg@vienna.at
 * (C) Copyright 2000 Yggdrasil Computing, Inc. (port of new PCI interface
 *               support from usb-ohci.c by Adam Richter, adam@yggdrasil.com).
 * (C) Copyright 1999 Gregory P. Smith (from usb-ohci.c)
 * (C) Copyright 2004-2007 Alan Stern, stern@rowland.harvard.edu
 */

#include <linux/device.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>

static int uhci_grlib_init(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        /*
         * Probe to determine the endianness of the controller.
         * We know that bit 7 of the PORTSC1 register is always set
         * and bit 15 is always clear.  If uhci_readw() yields a value
         * with bit 7 (0x80) turned on then the current little-endian
         * setting is correct.  Otherwise we assume the value was
         * byte-swapped; hence the register interface and presumably
         * also the descriptors are big-endian.
         */
        if (!(uhci_readw(uhci, USBPORTSC1) & 0x80)) {
                uhci->big_endian_mmio = 1;
                uhci->big_endian_desc = 1;
        }

        uhci->rh_numports = uhci_count_ports(hcd);

        /* Set up pointers to to generic functions */
        uhci->reset_hc = uhci_generic_reset_hc;
        uhci->check_and_reset_hc = uhci_generic_check_and_reset_hc;
        /* No special actions need to be taken for the functions below */
        uhci->configure_hc = NULL;
        uhci->resume_detect_interrupts_are_broken = NULL;
        uhci->global_suspend_mode_is_broken = NULL;

        /* Reset if the controller isn't already safely quiescent. */
        check_and_reset_hc(uhci);
        return 0;
}

static const struct hc_driver uhci_grlib_hc_driver = {
        .description =          hcd_name,
        .product_desc =         "GRLIB GRUSBHC UHCI Host Controller",
        .hcd_priv_size =        sizeof(struct uhci_hcd),

        /* Generic hardware linkage */
        .irq =                  uhci_irq,
        .flags =                HCD_MEMORY | HCD_USB11,

        /* Basic lifecycle operations */
        .reset =                uhci_grlib_init,
        .start =                uhci_start,
#ifdef CONFIG_PM
        .pci_suspend =          NULL,
        .pci_resume =           NULL,
        .bus_suspend =          uhci_rh_suspend,
        .bus_resume =           uhci_rh_resume,
#endif
        .stop =                 uhci_stop,

        .urb_enqueue =          uhci_urb_enqueue,
        .urb_dequeue =          uhci_urb_dequeue,

        .endpoint_disable =     uhci_hcd_endpoint_disable,
        .get_frame_number =     uhci_hcd_get_frame_number,

        .hub_status_data =      uhci_hub_status_data,
        .hub_control =          uhci_hub_control,
};


static int uhci_hcd_grlib_probe(struct platform_device *op)
{
        struct device_node *dn = op->dev.of_node;
        struct usb_hcd *hcd;
        struct uhci_hcd *uhci = NULL;
        struct resource res;
        int irq;
        int rv;

        if (usb_disabled())
                return -ENODEV;

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

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

        /* usb_create_hcd requires dma_mask != NULL */
        op->dev.dma_mask = &op->dev.coherent_dma_mask;
        hcd = usb_create_hcd(&uhci_grlib_hc_driver, &op->dev,
                        "GRUSBHC UHCI 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_usb;
        }

        hcd->regs = devm_ioremap_resource(&op->dev, &res);
        if (IS_ERR(hcd->regs)) {
                rv = PTR_ERR(hcd->regs);
                goto err_irq;
        }

        uhci = hcd_to_uhci(hcd);

        uhci->regs = hcd->regs;

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

        device_wakeup_enable(hcd->self.controller);
        return 0;

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

        return rv;
}

static int uhci_hcd_grlib_remove(struct platform_device *op)
{
        struct usb_hcd *hcd = platform_get_drvdata(op);

        dev_dbg(&op->dev, "stopping GRLIB GRUSBHC UHCI USB Controller\n");

        usb_remove_hcd(hcd);

        irq_dispose_mapping(hcd->irq);
        usb_put_hcd(hcd);

        return 0;
}

/* Make sure the controller is quiescent and that we're not using it
 * any more.  This is mainly for the benefit of programs which, like kexec,
 * expect the hardware to be idle: not doing DMA or generating IRQs.
 *
 * This routine may be called in a damaged or failing kernel.  Hence we
 * do not acquire the spinlock before shutting down the controller.
 */
static void uhci_hcd_grlib_shutdown(struct platform_device *op)
{
        struct usb_hcd *hcd = platform_get_drvdata(op);

        uhci_hc_died(hcd_to_uhci(hcd));
}

static const struct of_device_id uhci_hcd_grlib_of_match[] = {
        { .name = "GAISLER_UHCI", },
        { .name = "01_027", },
        {},
};
MODULE_DEVICE_TABLE(of, uhci_hcd_grlib_of_match);


static struct platform_driver uhci_grlib_driver = {
        .probe          = uhci_hcd_grlib_probe,
        .remove         = uhci_hcd_grlib_remove,
        .shutdown       = uhci_hcd_grlib_shutdown,
        .driver = {
                .name = "grlib-uhci",
                .of_match_table = uhci_hcd_grlib_of_match,
        },
};