/*
 * xhci-plat.c - xHCI host controller driver platform Bus Glue.
 *
 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com
 * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 *
 * A lot of code borrowed from the Linux xHCI driver.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 */

#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/dma-mapping.h>

#include "xhci.h"

static struct hc_driver __read_mostly xhci_plat_hc_driver;

static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
{
	/*
	 * As of now platform drivers don't provide MSI support so we ensure
	 * here that the generic code does not try to make a pci_dev from our
	 * dev struct in order to setup MSI
	 */
	xhci->quirks |= XHCI_PLAT;
}

/* called during probe() after chip reset completes */
static int xhci_plat_setup(struct usb_hcd *hcd)
{
	return xhci_gen_setup(hcd, xhci_plat_quirks);
}

static int xhci_plat_probe(struct platform_device *pdev)
{
	const struct hc_driver	*driver;
	struct xhci_hcd		*xhci;
	struct resource         *res;
	struct usb_hcd		*hcd;
	int			ret;
	int			irq;

	if (usb_disabled())
		return -ENODEV;

	driver = &xhci_plat_hc_driver;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return -ENODEV;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -ENODEV;

	/* Initialize dma_mask and coherent_dma_mask to 32-bits */
	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
	if (ret)
		return ret;
	if (!pdev->dev.dma_mask)
		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
	else
		dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));

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

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

	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
				driver->description)) {
		dev_dbg(&pdev->dev, "controller already in use\n");
		ret = -EBUSY;
		goto put_hcd;
	}

	hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
	if (!hcd->regs) {
		dev_dbg(&pdev->dev, "error mapping memory\n");
		ret = -EFAULT;
		goto release_mem_region;
	}

	ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
	if (ret)
		goto unmap_registers;
	device_wakeup_enable(hcd->self.controller);

	/* USB 2.0 roothub is stored in the platform_device now. */
	hcd = platform_get_drvdata(pdev);
	xhci = hcd_to_xhci(hcd);
	xhci->shared_hcd = usb_create_shared_hcd(driver, &pdev->dev,
			dev_name(&pdev->dev), hcd);
	if (!xhci->shared_hcd) {
		ret = -ENOMEM;
		goto dealloc_usb2_hcd;
	}

	/*
	 * Set the xHCI pointer before xhci_plat_setup() (aka hcd_driver.reset)
	 * is called by usb_add_hcd().
	 */
	*((struct xhci_hcd **) xhci->shared_hcd->hcd_priv) = xhci;

	ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
	if (ret)
		goto put_usb3_hcd;

	return 0;

put_usb3_hcd:
	usb_put_hcd(xhci->shared_hcd);

dealloc_usb2_hcd:
	usb_remove_hcd(hcd);

unmap_registers:
	iounmap(hcd->regs);

release_mem_region:
	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);

put_hcd:
	usb_put_hcd(hcd);

	return ret;
}

static int xhci_plat_remove(struct platform_device *dev)
{
	struct usb_hcd	*hcd = platform_get_drvdata(dev);
	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);

	usb_remove_hcd(xhci->shared_hcd);
	usb_put_hcd(xhci->shared_hcd);

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

	return 0;
}

#ifdef CONFIG_PM
static int xhci_plat_suspend(struct device *dev)
{
	struct usb_hcd	*hcd = dev_get_drvdata(dev);
	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);

	/*
	 * xhci_suspend() needs `do_wakeup` to know whether host is allowed
	 * to do wakeup during suspend. Since xhci_plat_suspend is currently
	 * only designed for system suspend, device_may_wakeup() is enough
	 * to dertermine whether host is allowed to do wakeup. Need to
	 * reconsider this when xhci_plat_suspend enlarges its scope, e.g.,
	 * also applies to runtime suspend.
	 */
	return xhci_suspend(xhci, device_may_wakeup(dev));
}

static int xhci_plat_resume(struct device *dev)
{
	struct usb_hcd	*hcd = dev_get_drvdata(dev);
	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);

	return xhci_resume(xhci, 0);
}

static const struct dev_pm_ops xhci_plat_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(xhci_plat_suspend, xhci_plat_resume)
};
#define DEV_PM_OPS	(&xhci_plat_pm_ops)
#else
#define DEV_PM_OPS	NULL
#endif /* CONFIG_PM */

#ifdef CONFIG_OF
static const struct of_device_id usb_xhci_of_match[] = {
	{ .compatible = "xhci-platform" },
	{ },
};
MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
#endif

static struct platform_driver usb_xhci_driver = {
	.probe	= xhci_plat_probe,
	.remove	= xhci_plat_remove,
	.driver	= {
		.name = "xhci-hcd",
		.pm = DEV_PM_OPS,
		.of_match_table = of_match_ptr(usb_xhci_of_match),
	},
};
MODULE_ALIAS("platform:xhci-hcd");

int xhci_register_plat(void)
{
	xhci_init_driver(&xhci_plat_hc_driver, xhci_plat_setup);
	return platform_driver_register(&usb_xhci_driver);
}

void xhci_unregister_plat(void)
{
	platform_driver_unregister(&usb_xhci_driver);
}