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/*
 * driver for NXP USB Host devices
 *
 * Currently supported OHCI host devices:
 * - NXP LPC32xx
 *
 * Authors: Dmitry Chigirev <source@mvista.com>
 *	    Vitaly Wool <vitalywool@gmail.com>
 *
 * register initialization is based on code examples provided by Philips
 * Copyright (c) 2005 Koninklijke Philips Electronics N.V.
 *
 * NOTE: This driver does not have suspend/resume functionality
 * This driver is intended for engineering development purposes only
 *
 * 2005-2006 (c) MontaVista Software, Inc. 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/clk.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/usb/isp1301.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>

#include "ohci.h"

#include <mach/hardware.h>

#define USB_CONFIG_BASE		0x31020000
#define USB_OTG_STAT_CONTROL	IO_ADDRESS(USB_CONFIG_BASE + 0x110)

/* USB_OTG_STAT_CONTROL bit defines */
#define TRANSPARENT_I2C_EN	(1 << 7)
#define HOST_EN			(1 << 0)

/* On LPC32xx, those are undefined */
#ifndef start_int_set_falling_edge
#define start_int_set_falling_edge(irq)
#define start_int_set_rising_edge(irq)
#define start_int_ack(irq)
#define start_int_mask(irq)
#define start_int_umask(irq)
#endif

#define DRIVER_DESC "OHCI NXP driver"

static const char hcd_name[] = "ohci-nxp";
static struct hc_driver __read_mostly ohci_nxp_hc_driver;

static struct i2c_client *isp1301_i2c_client;

static struct clk *usb_host_clk;

static void isp1301_configure_lpc32xx(void)
{
	/* LPC32XX only supports DAT_SE0 USB mode */
	/* This sequence is important */

	/* Disable transparent UART mode first */
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		(ISP1301_I2C_MODE_CONTROL_1 | ISP1301_I2C_REG_CLEAR_ADDR),
		MC1_UART_EN);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		(ISP1301_I2C_MODE_CONTROL_1 | ISP1301_I2C_REG_CLEAR_ADDR),
		~MC1_SPEED_REG);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
				  ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		  (ISP1301_I2C_MODE_CONTROL_2 | ISP1301_I2C_REG_CLEAR_ADDR),
		  ~0);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		ISP1301_I2C_MODE_CONTROL_2,
		(MC2_BI_DI | MC2_PSW_EN | MC2_SPD_SUSP_CTRL));
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		(ISP1301_I2C_OTG_CONTROL_1 | ISP1301_I2C_REG_CLEAR_ADDR), ~0);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		ISP1301_I2C_OTG_CONTROL_1,
		(OTG1_DM_PULLDOWN | OTG1_DP_PULLDOWN));
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		(ISP1301_I2C_OTG_CONTROL_1 | ISP1301_I2C_REG_CLEAR_ADDR),
		(OTG1_DM_PULLUP | OTG1_DP_PULLUP));
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		ISP1301_I2C_INTERRUPT_LATCH | ISP1301_I2C_REG_CLEAR_ADDR, ~0);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		ISP1301_I2C_INTERRUPT_FALLING | ISP1301_I2C_REG_CLEAR_ADDR,
		~0);
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		ISP1301_I2C_INTERRUPT_RISING | ISP1301_I2C_REG_CLEAR_ADDR, ~0);

	printk(KERN_INFO "ISP1301 Vendor ID  : 0x%04x\n",
	      i2c_smbus_read_word_data(isp1301_i2c_client, 0x00));
	printk(KERN_INFO "ISP1301 Product ID : 0x%04x\n",
	      i2c_smbus_read_word_data(isp1301_i2c_client, 0x02));
	printk(KERN_INFO "ISP1301 Version ID : 0x%04x\n",
	      i2c_smbus_read_word_data(isp1301_i2c_client, 0x14));
}

static void isp1301_configure(void)
{
	isp1301_configure_lpc32xx();
}

static inline void isp1301_vbus_on(void)
{
	i2c_smbus_write_byte_data(isp1301_i2c_client, ISP1301_I2C_OTG_CONTROL_1,
				  OTG1_VBUS_DRV);
}

static inline void isp1301_vbus_off(void)
{
	i2c_smbus_write_byte_data(isp1301_i2c_client,
		ISP1301_I2C_OTG_CONTROL_1 | ISP1301_I2C_REG_CLEAR_ADDR,
		OTG1_VBUS_DRV);
}

static void ohci_nxp_start_hc(void)
{
	unsigned long tmp = __raw_readl(USB_OTG_STAT_CONTROL) | HOST_EN;

	__raw_writel(tmp, USB_OTG_STAT_CONTROL);
	isp1301_vbus_on();
}

static void ohci_nxp_stop_hc(void)
{
	unsigned long tmp;

	isp1301_vbus_off();
	tmp = __raw_readl(USB_OTG_STAT_CONTROL) & ~HOST_EN;
	__raw_writel(tmp, USB_OTG_STAT_CONTROL);
}

static int ohci_hcd_nxp_probe(struct platform_device *pdev)
{
	struct usb_hcd *hcd = 0;
	const struct hc_driver *driver = &ohci_nxp_hc_driver;
	struct resource *res;
	int ret = 0, irq;
	struct device_node *isp1301_node;

	if (pdev->dev.of_node) {
		isp1301_node = of_parse_phandle(pdev->dev.of_node,
						"transceiver", 0);
	} else {
		isp1301_node = NULL;
	}

	isp1301_i2c_client = isp1301_get_client(isp1301_node);
	if (!isp1301_i2c_client)
		return -EPROBE_DEFER;

	ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
	if (ret)
		goto fail_disable;

	dev_dbg(&pdev->dev, "%s: " DRIVER_DESC " (nxp)\n", hcd_name);
	if (usb_disabled()) {
		dev_err(&pdev->dev, "USB is disabled\n");
		ret = -ENODEV;
		goto fail_disable;
	}

	/* Enable USB host clock */
	usb_host_clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(usb_host_clk)) {
		dev_err(&pdev->dev, "failed to acquire USB OHCI clock\n");
		ret = PTR_ERR(usb_host_clk);
		goto fail_disable;
	}

	ret = clk_prepare_enable(usb_host_clk);
	if (ret < 0) {
		dev_err(&pdev->dev, "failed to start USB OHCI clock\n");
		goto fail_disable;
	}

	isp1301_configure();

	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
	if (!hcd) {
		dev_err(&pdev->dev, "Failed to allocate HC buffer\n");
		ret = -ENOMEM;
		goto fail_hcd;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(hcd->regs)) {
		ret = PTR_ERR(hcd->regs);
		goto fail_resource;
	}
	hcd->rsrc_start = res->start;
	hcd->rsrc_len = resource_size(res);

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		ret = -ENXIO;
		goto fail_resource;
	}

	ohci_nxp_start_hc();
	platform_set_drvdata(pdev, hcd);

	dev_info(&pdev->dev, "at 0x%p, irq %d\n", hcd->regs, hcd->irq);
	ret = usb_add_hcd(hcd, irq, 0);
	if (ret == 0) {
		device_wakeup_enable(hcd->self.controller);
		return ret;
	}

	ohci_nxp_stop_hc();
fail_resource:
	usb_put_hcd(hcd);
fail_hcd:
	clk_disable_unprepare(usb_host_clk);
fail_disable:
	isp1301_i2c_client = NULL;
	return ret;
}

static int ohci_hcd_nxp_remove(struct platform_device *pdev)
{
	struct usb_hcd *hcd = platform_get_drvdata(pdev);

	usb_remove_hcd(hcd);
	ohci_nxp_stop_hc();
	usb_put_hcd(hcd);
	clk_disable_unprepare(usb_host_clk);
	isp1301_i2c_client = NULL;

	return 0;
}

/* work with hotplug and coldplug */
MODULE_ALIAS("platform:usb-ohci");

#ifdef CONFIG_OF
static const struct of_device_id ohci_hcd_nxp_match[] = {
	{ .compatible = "nxp,ohci-nxp" },
	{},
};
MODULE_DEVICE_TABLE(of, ohci_hcd_nxp_match);
#endif

static struct platform_driver ohci_hcd_nxp_driver = {
	.driver = {
		.name = "usb-ohci",
		.of_match_table = of_match_ptr(ohci_hcd_nxp_match),
	},
	.probe = ohci_hcd_nxp_probe,
	.remove = ohci_hcd_nxp_remove,
};

static int __init ohci_nxp_init(void)
{
	if (usb_disabled())
		return -ENODEV;

	pr_info("%s: " DRIVER_DESC "\n", hcd_name);

	ohci_init_driver(&ohci_nxp_hc_driver, NULL);
	return platform_driver_register(&ohci_hcd_nxp_driver);
}
module_init(ohci_nxp_init);

static void __exit ohci_nxp_cleanup(void)
{
	platform_driver_unregister(&ohci_hcd_nxp_driver);
}
module_exit(ohci_nxp_cleanup);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL v2");