drivers/usb/host/isp1760-if.c - kernel/msm-5.4 - Gitiles

 /*
  * Glue code for the ISP1760 driver and bus
  * Currently there is support for
  * - OpenFirmware
  * - PCI
  * - PDEV (generic platform device centralized driver model)
  *
  * (c) 2007 Sebastian Siewior <bigeasy@linutronix.de>
  *
  */

 #include <linux/usb.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/usb/isp1760.h>
 #include <linux/usb/hcd.h>

 #include "isp1760-hcd.h"

 #if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/of_gpio.h>
 #endif

 #ifdef CONFIG_PCI
 #include <linux/pci.h>
 #endif

 #if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
 struct isp1760 {
 	struct usb_hcd *hcd;
 	int rst_gpio;
 };

 static int of_isp1760_probe(struct platform_device *dev)
 {
 	struct isp1760 *drvdata;
 	struct device_node *dp = dev->dev.of_node;
 	struct resource *res;
 	struct resource memory;
 	struct of_irq oirq;
 	int virq;
 	resource_size_t res_len;
 	int ret;
 	unsigned int devflags = 0;
 	enum of_gpio_flags gpio_flags;
 	u32 bus_width = 0;

 	drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
 	if (!drvdata)
 		return -ENOMEM;

 	ret = of_address_to_resource(dp, 0, &memory);
 	if (ret) {
 		ret = -ENXIO;
 		goto free_data;
 	}

 	res_len = resource_size(&memory);

 	res = request_mem_region(memory.start, res_len, dev_name(&dev->dev));
 	if (!res) {
 		ret = -EBUSY;
 		goto free_data;
 	}

 	if (of_irq_map_one(dp, 0, &oirq)) {
 		ret = -ENODEV;
 		goto release_reg;
 	}

 	virq = irq_create_of_mapping(oirq.controller, oirq.specifier,
 			oirq.size);

 	if (of_device_is_compatible(dp, "nxp,usb-isp1761"))
 		devflags |= ISP1760_FLAG_ISP1761;

 	/* Some systems wire up only 16 of the 32 data lines */
 	of_property_read_u32(dp, "bus-width", &bus_width);
 	if (bus_width == 16)
 		devflags |= ISP1760_FLAG_BUS_WIDTH_16;

 	if (of_get_property(dp, "port1-otg", NULL) != NULL)
 		devflags |= ISP1760_FLAG_OTG_EN;

 	if (of_get_property(dp, "analog-oc", NULL) != NULL)
 		devflags |= ISP1760_FLAG_ANALOG_OC;

 	if (of_get_property(dp, "dack-polarity", NULL) != NULL)
 		devflags |= ISP1760_FLAG_DACK_POL_HIGH;

 	if (of_get_property(dp, "dreq-polarity", NULL) != NULL)
 		devflags |= ISP1760_FLAG_DREQ_POL_HIGH;

 	drvdata->rst_gpio = of_get_gpio_flags(dp, 0, &gpio_flags);
 	if (gpio_is_valid(drvdata->rst_gpio)) {
 		ret = gpio_request(drvdata->rst_gpio, dev_name(&dev->dev));
 		if (!ret) {
 			if (!(gpio_flags & OF_GPIO_ACTIVE_LOW)) {
 				devflags |= ISP1760_FLAG_RESET_ACTIVE_HIGH;
 				gpio_direction_output(drvdata->rst_gpio, 0);
 			} else {
 				gpio_direction_output(drvdata->rst_gpio, 1);
 			}
 		} else {
 			drvdata->rst_gpio = ret;
 		}
 	}

 	drvdata->hcd = isp1760_register(memory.start, res_len, virq,
 					IRQF_SHARED, drvdata->rst_gpio,
 					&dev->dev, dev_name(&dev->dev),
 					devflags);
 	if (IS_ERR(drvdata->hcd)) {
 		ret = PTR_ERR(drvdata->hcd);
 		goto free_gpio;
 	}

 	dev_set_drvdata(&dev->dev, drvdata);
 	return ret;

 free_gpio:
 	if (gpio_is_valid(drvdata->rst_gpio))
 		gpio_free(drvdata->rst_gpio);
 release_reg:
 	release_mem_region(memory.start, res_len);
 free_data:
 	kfree(drvdata);
 	return ret;
 }

 static int of_isp1760_remove(struct platform_device *dev)
 {
 	struct isp1760 *drvdata = dev_get_drvdata(&dev->dev);

 	dev_set_drvdata(&dev->dev, NULL);

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

 	if (gpio_is_valid(drvdata->rst_gpio))
 		gpio_free(drvdata->rst_gpio);

 	kfree(drvdata);
 	return 0;
 }

 static const struct of_device_id of_isp1760_match[] = {
 	{
 		.compatible = "nxp,usb-isp1760",
 	},
 	{
 		.compatible = "nxp,usb-isp1761",
 	},
 	{ },
 };
 MODULE_DEVICE_TABLE(of, of_isp1760_match);

 static struct platform_driver isp1760_of_driver = {
 	.driver = {
 		.name = "nxp-isp1760",
 		.owner = THIS_MODULE,
 		.of_match_table = of_isp1760_match,
 	},
 	.probe          = of_isp1760_probe,
 	.remove         = of_isp1760_remove,
 };
 #endif

 #ifdef CONFIG_PCI
 static int __devinit isp1761_pci_probe(struct pci_dev *dev,
 		const struct pci_device_id *id)
 {
 	u8 latency, limit;
 	__u32 reg_data;
 	int retry_count;
 	struct usb_hcd *hcd;
 	unsigned int devflags = 0;
 	int ret_status = 0;

 	resource_size_t pci_mem_phy0;
 	resource_size_t memlength;

 	u8 __iomem *chip_addr;
 	u8 __iomem *iobase;
 	resource_size_t nxp_pci_io_base;
 	resource_size_t iolength;

 	if (usb_disabled())
 		return -ENODEV;

 	if (pci_enable_device(dev) < 0)
 		return -ENODEV;

 	if (!dev->irq)
 		return -ENODEV;

 	/* Grab the PLX PCI mem maped port start address we need  */
 	nxp_pci_io_base = pci_resource_start(dev, 0);
 	iolength = pci_resource_len(dev, 0);

 	if (!request_mem_region(nxp_pci_io_base, iolength, "ISP1761 IO MEM")) {
 		printk(KERN_ERR "request region #1\n");
 		return -EBUSY;
 	}

 	iobase = ioremap_nocache(nxp_pci_io_base, iolength);
 	if (!iobase) {
 		printk(KERN_ERR "ioremap #1\n");
 		ret_status = -ENOMEM;
 		goto cleanup1;
 	}
 	/* Grab the PLX PCI shared memory of the ISP 1761 we need  */
 	pci_mem_phy0 = pci_resource_start(dev, 3);
 	memlength = pci_resource_len(dev, 3);
 	if (memlength < 0xffff) {
 		printk(KERN_ERR "memory length for this resource is wrong\n");
 		ret_status = -ENOMEM;
 		goto cleanup2;
 	}

 	if (!request_mem_region(pci_mem_phy0, memlength, "ISP-PCI")) {
 		printk(KERN_ERR "host controller already in use\n");
 		ret_status = -EBUSY;
 		goto cleanup2;
 	}

 	/* map available memory */
 	chip_addr = ioremap_nocache(pci_mem_phy0,memlength);
 	if (!chip_addr) {
 		printk(KERN_ERR "Error ioremap failed\n");
 		ret_status = -ENOMEM;
 		goto cleanup3;
 	}

 	/* bad pci latencies can contribute to overruns */
 	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &latency);
 	if (latency) {
 		pci_read_config_byte(dev, PCI_MAX_LAT, &limit);
 		if (limit && limit < latency)
 			pci_write_config_byte(dev, PCI_LATENCY_TIMER, limit);
 	}

 	/* Try to check whether we can access Scratch Register of
 	 * Host Controller or not. The initial PCI access is retried until
 	 * local init for the PCI bridge is completed
 	 */
 	retry_count = 20;
 	reg_data = 0;
 	while ((reg_data != 0xFACE) && retry_count) {
 		/*by default host is in 16bit mode, so
 		 * io operations at this stage must be 16 bit
 		 * */
 		writel(0xface, chip_addr + HC_SCRATCH_REG);
 		udelay(100);
 		reg_data = readl(chip_addr + HC_SCRATCH_REG) & 0x0000ffff;
 		retry_count--;
 	}

 	iounmap(chip_addr);

 	/* Host Controller presence is detected by writing to scratch register
 	 * and reading back and checking the contents are same or not
 	 */
 	if (reg_data != 0xFACE) {
 		dev_err(&dev->dev, "scratch register mismatch %x\n", reg_data);
 		ret_status = -ENOMEM;
 		goto cleanup3;
 	}

 	pci_set_master(dev);

 	/* configure PLX PCI chip to pass interrupts */
 #define PLX_INT_CSR_REG 0x68
 	reg_data = readl(iobase + PLX_INT_CSR_REG);
 	reg_data |= 0x900;
 	writel(reg_data, iobase + PLX_INT_CSR_REG);

 	dev->dev.dma_mask = NULL;
 	hcd = isp1760_register(pci_mem_phy0, memlength, dev->irq,
 		IRQF_SHARED, -ENOENT, &dev->dev, dev_name(&dev->dev),
 		devflags);
 	if (IS_ERR(hcd)) {
 		ret_status = -ENODEV;
 		goto cleanup3;
 	}

 	/* done with PLX IO access */
 	iounmap(iobase);
 	release_mem_region(nxp_pci_io_base, iolength);

 	pci_set_drvdata(dev, hcd);
 	return 0;

 cleanup3:
 	release_mem_region(pci_mem_phy0, memlength);
 cleanup2:
 	iounmap(iobase);
 cleanup1:
 	release_mem_region(nxp_pci_io_base, iolength);
 	return ret_status;
 }

 static void isp1761_pci_remove(struct pci_dev *dev)
 {
 	struct usb_hcd *hcd;

 	hcd = pci_get_drvdata(dev);

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

 	pci_disable_device(dev);
 }

 static void isp1761_pci_shutdown(struct pci_dev *dev)
 {
 	printk(KERN_ERR "ips1761_pci_shutdown\n");
 }

 static const struct pci_device_id isp1760_plx [] = {
 	{
 		.class          = PCI_CLASS_BRIDGE_OTHER << 8,
 		.class_mask     = ~0,
 		.vendor		= PCI_VENDOR_ID_PLX,
 		.device		= 0x5406,
 		.subvendor	= PCI_VENDOR_ID_PLX,
 		.subdevice	= 0x9054,
 	},
 	{ }
 };
 MODULE_DEVICE_TABLE(pci, isp1760_plx);

 static struct pci_driver isp1761_pci_driver = {
 	.name =         "isp1760",
 	.id_table =     isp1760_plx,
 	.probe =        isp1761_pci_probe,
 	.remove =       isp1761_pci_remove,
 	.shutdown =     isp1761_pci_shutdown,
 };
 #endif

 static int __devinit isp1760_plat_probe(struct platform_device *pdev)
 {
 	int ret = 0;
 	struct usb_hcd *hcd;
 	struct resource *mem_res;
 	struct resource *irq_res;
 	resource_size_t mem_size;
 	struct isp1760_platform_data *priv = pdev->dev.platform_data;
 	unsigned int devflags = 0;
 	unsigned long irqflags = IRQF_SHARED;

 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!mem_res) {
 		pr_warning("isp1760: Memory resource not available\n");
 		ret = -ENODEV;
 		goto out;
 	}
 	mem_size = resource_size(mem_res);
 	if (!request_mem_region(mem_res->start, mem_size, "isp1760")) {
 		pr_warning("isp1760: Cannot reserve the memory resource\n");
 		ret = -EBUSY;
 		goto out;
 	}

 	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!irq_res) {
 		pr_warning("isp1760: IRQ resource not available\n");
 		return -ENODEV;
 	}
 	irqflags |= irq_res->flags & IRQF_TRIGGER_MASK;

 	if (priv) {
 		if (priv->is_isp1761)
 			devflags |= ISP1760_FLAG_ISP1761;
 		if (priv->bus_width_16)
 			devflags |= ISP1760_FLAG_BUS_WIDTH_16;
 		if (priv->port1_otg)
 			devflags |= ISP1760_FLAG_OTG_EN;
 		if (priv->analog_oc)
 			devflags |= ISP1760_FLAG_ANALOG_OC;
 		if (priv->dack_polarity_high)
 			devflags |= ISP1760_FLAG_DACK_POL_HIGH;
 		if (priv->dreq_polarity_high)
 			devflags |= ISP1760_FLAG_DREQ_POL_HIGH;
 	}

 	hcd = isp1760_register(mem_res->start, mem_size, irq_res->start,
 			       irqflags, -ENOENT,
 			       &pdev->dev, dev_name(&pdev->dev), devflags);

 	dev_set_drvdata(&pdev->dev, hcd);

 	if (IS_ERR(hcd)) {
 		pr_warning("isp1760: Failed to register the HCD device\n");
 		ret = -ENODEV;
 		goto cleanup;
 	}

 	pr_info("ISP1760 USB device initialised\n");
 	return ret;

 cleanup:
 	release_mem_region(mem_res->start, mem_size);
 out:
 	return ret;
 }

 static int __devexit isp1760_plat_remove(struct platform_device *pdev)
 {
 	struct resource *mem_res;
 	resource_size_t mem_size;
 	struct usb_hcd *hcd = dev_get_drvdata(&pdev->dev);

 	usb_remove_hcd(hcd);

 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	mem_size = resource_size(mem_res);
 	release_mem_region(mem_res->start, mem_size);

 	usb_put_hcd(hcd);

 	return 0;
 }

 static struct platform_driver isp1760_plat_driver = {
 	.probe	= isp1760_plat_probe,
 	.remove	= __devexit_p(isp1760_plat_remove),
 	.driver	= {
 		.name	= "isp1760",
 	},
 };

 static int __init isp1760_init(void)
 {
 	int ret, any_ret = -ENODEV;

 	init_kmem_once();

 	ret = platform_driver_register(&isp1760_plat_driver);
 	if (!ret)
 		any_ret = 0;
 #if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
 	ret = platform_driver_register(&isp1760_of_driver);
 	if (!ret)
 		any_ret = 0;
 #endif
 #ifdef CONFIG_PCI
 	ret = pci_register_driver(&isp1761_pci_driver);
 	if (!ret)
 		any_ret = 0;
 #endif

 	if (any_ret)
 		deinit_kmem_cache();
 	return any_ret;
 }
 module_init(isp1760_init);

 static void __exit isp1760_exit(void)
 {
 	platform_driver_unregister(&isp1760_plat_driver);
 #if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
 	platform_driver_unregister(&isp1760_of_driver);
 #endif
 #ifdef CONFIG_PCI
 	pci_unregister_driver(&isp1761_pci_driver);
 #endif
 	deinit_kmem_cache();
 }
 module_exit(isp1760_exit);
	/*
	* Glue code for the ISP1760 driver and bus
	* Currently there is support for
	* - OpenFirmware
	* - PCI
	* - PDEV (generic platform device centralized driver model)
	*
	* (c) 2007 Sebastian Siewior <bigeasy@linutronix.de>
	*
	*/

	#include <linux/usb.h>
	#include <linux/io.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/usb/isp1760.h>
	#include <linux/usb/hcd.h>

	#include "isp1760-hcd.h"

	#if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
	#include <linux/slab.h>
	#include <linux/of.h>
	#include <linux/of_platform.h>
	#include <linux/of_address.h>
	#include <linux/of_irq.h>
	#include <linux/of_gpio.h>
	#endif

	#ifdef CONFIG_PCI
	#include <linux/pci.h>
	#endif

	#if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
	struct isp1760 {
	struct usb_hcd *hcd;
	int rst_gpio;
	};

	static int of_isp1760_probe(struct platform_device *dev)
	{
	struct isp1760 *drvdata;
	struct device_node *dp = dev->dev.of_node;
	struct resource *res;
	struct resource memory;
	struct of_irq oirq;
	int virq;
	resource_size_t res_len;
	int ret;
	unsigned int devflags = 0;
	enum of_gpio_flags gpio_flags;
	u32 bus_width = 0;

	drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
	if (!drvdata)
	return -ENOMEM;

	ret = of_address_to_resource(dp, 0, &memory);
	if (ret) {
	ret = -ENXIO;
	goto free_data;
	}

	res_len = resource_size(&memory);

	res = request_mem_region(memory.start, res_len, dev_name(&dev->dev));
	if (!res) {
	ret = -EBUSY;
	goto free_data;
	}

	if (of_irq_map_one(dp, 0, &oirq)) {
	ret = -ENODEV;
	goto release_reg;
	}

	virq = irq_create_of_mapping(oirq.controller, oirq.specifier,
	oirq.size);

	if (of_device_is_compatible(dp, "nxp,usb-isp1761"))
	devflags \|= ISP1760_FLAG_ISP1761;

	/* Some systems wire up only 16 of the 32 data lines */
	of_property_read_u32(dp, "bus-width", &bus_width);
	if (bus_width == 16)
	devflags \|= ISP1760_FLAG_BUS_WIDTH_16;

	if (of_get_property(dp, "port1-otg", NULL) != NULL)
	devflags \|= ISP1760_FLAG_OTG_EN;

	if (of_get_property(dp, "analog-oc", NULL) != NULL)
	devflags \|= ISP1760_FLAG_ANALOG_OC;

	if (of_get_property(dp, "dack-polarity", NULL) != NULL)
	devflags \|= ISP1760_FLAG_DACK_POL_HIGH;

	if (of_get_property(dp, "dreq-polarity", NULL) != NULL)
	devflags \|= ISP1760_FLAG_DREQ_POL_HIGH;

	drvdata->rst_gpio = of_get_gpio_flags(dp, 0, &gpio_flags);
	if (gpio_is_valid(drvdata->rst_gpio)) {
	ret = gpio_request(drvdata->rst_gpio, dev_name(&dev->dev));
	if (!ret) {
	if (!(gpio_flags & OF_GPIO_ACTIVE_LOW)) {
	devflags \|= ISP1760_FLAG_RESET_ACTIVE_HIGH;
	gpio_direction_output(drvdata->rst_gpio, 0);
	} else {
	gpio_direction_output(drvdata->rst_gpio, 1);
	}
	} else {
	drvdata->rst_gpio = ret;
	}
	}

	drvdata->hcd = isp1760_register(memory.start, res_len, virq,
	IRQF_SHARED, drvdata->rst_gpio,
	&dev->dev, dev_name(&dev->dev),
	devflags);
	if (IS_ERR(drvdata->hcd)) {
	ret = PTR_ERR(drvdata->hcd);
	goto free_gpio;
	}

	dev_set_drvdata(&dev->dev, drvdata);
	return ret;

	free_gpio:
	if (gpio_is_valid(drvdata->rst_gpio))
	gpio_free(drvdata->rst_gpio);
	release_reg:
	release_mem_region(memory.start, res_len);
	free_data:
	kfree(drvdata);
	return ret;
	}

	static int of_isp1760_remove(struct platform_device *dev)
	{
	struct isp1760 *drvdata = dev_get_drvdata(&dev->dev);

	dev_set_drvdata(&dev->dev, NULL);

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

	if (gpio_is_valid(drvdata->rst_gpio))
	gpio_free(drvdata->rst_gpio);

	kfree(drvdata);
	return 0;
	}

	static const struct of_device_id of_isp1760_match[] = {
	{
	.compatible = "nxp,usb-isp1760",
	},
	{
	.compatible = "nxp,usb-isp1761",
	},
	{ },
	};
	MODULE_DEVICE_TABLE(of, of_isp1760_match);

	static struct platform_driver isp1760_of_driver = {
	.driver = {
	.name = "nxp-isp1760",
	.owner = THIS_MODULE,
	.of_match_table = of_isp1760_match,
	},
	.probe = of_isp1760_probe,
	.remove = of_isp1760_remove,
	};
	#endif

	#ifdef CONFIG_PCI
	static int __devinit isp1761_pci_probe(struct pci_dev *dev,
	const struct pci_device_id *id)
	{
	u8 latency, limit;
	__u32 reg_data;
	int retry_count;
	struct usb_hcd *hcd;
	unsigned int devflags = 0;
	int ret_status = 0;

	resource_size_t pci_mem_phy0;
	resource_size_t memlength;

	u8 __iomem *chip_addr;
	u8 __iomem *iobase;
	resource_size_t nxp_pci_io_base;
	resource_size_t iolength;

	if (usb_disabled())
	return -ENODEV;

	if (pci_enable_device(dev) < 0)
	return -ENODEV;

	if (!dev->irq)
	return -ENODEV;

	/* Grab the PLX PCI mem maped port start address we need */
	nxp_pci_io_base = pci_resource_start(dev, 0);
	iolength = pci_resource_len(dev, 0);

	if (!request_mem_region(nxp_pci_io_base, iolength, "ISP1761 IO MEM")) {
	printk(KERN_ERR "request region #1\n");
	return -EBUSY;
	}

	iobase = ioremap_nocache(nxp_pci_io_base, iolength);
	if (!iobase) {
	printk(KERN_ERR "ioremap #1\n");
	ret_status = -ENOMEM;
	goto cleanup1;
	}
	/* Grab the PLX PCI shared memory of the ISP 1761 we need */
	pci_mem_phy0 = pci_resource_start(dev, 3);
	memlength = pci_resource_len(dev, 3);
	if (memlength < 0xffff) {
	printk(KERN_ERR "memory length for this resource is wrong\n");
	ret_status = -ENOMEM;
	goto cleanup2;
	}

	if (!request_mem_region(pci_mem_phy0, memlength, "ISP-PCI")) {
	printk(KERN_ERR "host controller already in use\n");
	ret_status = -EBUSY;
	goto cleanup2;
	}

	/* map available memory */
	chip_addr = ioremap_nocache(pci_mem_phy0,memlength);
	if (!chip_addr) {
	printk(KERN_ERR "Error ioremap failed\n");
	ret_status = -ENOMEM;
	goto cleanup3;
	}

	/* bad pci latencies can contribute to overruns */
	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &latency);
	if (latency) {
	pci_read_config_byte(dev, PCI_MAX_LAT, &limit);
	if (limit && limit < latency)
	pci_write_config_byte(dev, PCI_LATENCY_TIMER, limit);
	}

	/* Try to check whether we can access Scratch Register of
	* Host Controller or not. The initial PCI access is retried until
	* local init for the PCI bridge is completed
	*/
	retry_count = 20;
	reg_data = 0;
	while ((reg_data != 0xFACE) && retry_count) {
	/*by default host is in 16bit mode, so
	* io operations at this stage must be 16 bit
	* */
	writel(0xface, chip_addr + HC_SCRATCH_REG);
	udelay(100);
	reg_data = readl(chip_addr + HC_SCRATCH_REG) & 0x0000ffff;
	retry_count--;
	}

	iounmap(chip_addr);

	/* Host Controller presence is detected by writing to scratch register
	* and reading back and checking the contents are same or not
	*/
	if (reg_data != 0xFACE) {
	dev_err(&dev->dev, "scratch register mismatch %x\n", reg_data);
	ret_status = -ENOMEM;
	goto cleanup3;
	}

	pci_set_master(dev);

	/* configure PLX PCI chip to pass interrupts */
	#define PLX_INT_CSR_REG 0x68
	reg_data = readl(iobase + PLX_INT_CSR_REG);
	reg_data \|= 0x900;
	writel(reg_data, iobase + PLX_INT_CSR_REG);

	dev->dev.dma_mask = NULL;
	hcd = isp1760_register(pci_mem_phy0, memlength, dev->irq,
	IRQF_SHARED, -ENOENT, &dev->dev, dev_name(&dev->dev),
	devflags);
	if (IS_ERR(hcd)) {
	ret_status = -ENODEV;
	goto cleanup3;
	}

	/* done with PLX IO access */
	iounmap(iobase);
	release_mem_region(nxp_pci_io_base, iolength);

	pci_set_drvdata(dev, hcd);
	return 0;

	cleanup3:
	release_mem_region(pci_mem_phy0, memlength);
	cleanup2:
	iounmap(iobase);
	cleanup1:
	release_mem_region(nxp_pci_io_base, iolength);
	return ret_status;
	}

	static void isp1761_pci_remove(struct pci_dev *dev)
	{
	struct usb_hcd *hcd;

	hcd = pci_get_drvdata(dev);

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

	pci_disable_device(dev);
	}

	static void isp1761_pci_shutdown(struct pci_dev *dev)
	{
	printk(KERN_ERR "ips1761_pci_shutdown\n");
	}

	static const struct pci_device_id isp1760_plx [] = {
	{
	.class = PCI_CLASS_BRIDGE_OTHER << 8,
	.class_mask = ~0,
	.vendor = PCI_VENDOR_ID_PLX,
	.device = 0x5406,
	.subvendor = PCI_VENDOR_ID_PLX,
	.subdevice = 0x9054,
	},
	{ }
	};
	MODULE_DEVICE_TABLE(pci, isp1760_plx);

	static struct pci_driver isp1761_pci_driver = {
	.name = "isp1760",
	.id_table = isp1760_plx,
	.probe = isp1761_pci_probe,
	.remove = isp1761_pci_remove,
	.shutdown = isp1761_pci_shutdown,
	};
	#endif

	static int __devinit isp1760_plat_probe(struct platform_device *pdev)
	{
	int ret = 0;
	struct usb_hcd *hcd;
	struct resource *mem_res;
	struct resource *irq_res;
	resource_size_t mem_size;
	struct isp1760_platform_data *priv = pdev->dev.platform_data;
	unsigned int devflags = 0;
	unsigned long irqflags = IRQF_SHARED;

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem_res) {
	pr_warning("isp1760: Memory resource not available\n");
	ret = -ENODEV;
	goto out;
	}
	mem_size = resource_size(mem_res);
	if (!request_mem_region(mem_res->start, mem_size, "isp1760")) {
	pr_warning("isp1760: Cannot reserve the memory resource\n");
	ret = -EBUSY;
	goto out;
	}

	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	if (!irq_res) {
	pr_warning("isp1760: IRQ resource not available\n");
	return -ENODEV;
	}
	irqflags \|= irq_res->flags & IRQF_TRIGGER_MASK;

	if (priv) {
	if (priv->is_isp1761)
	devflags \|= ISP1760_FLAG_ISP1761;
	if (priv->bus_width_16)
	devflags \|= ISP1760_FLAG_BUS_WIDTH_16;
	if (priv->port1_otg)
	devflags \|= ISP1760_FLAG_OTG_EN;
	if (priv->analog_oc)
	devflags \|= ISP1760_FLAG_ANALOG_OC;
	if (priv->dack_polarity_high)
	devflags \|= ISP1760_FLAG_DACK_POL_HIGH;
	if (priv->dreq_polarity_high)
	devflags \|= ISP1760_FLAG_DREQ_POL_HIGH;
	}

	hcd = isp1760_register(mem_res->start, mem_size, irq_res->start,
	irqflags, -ENOENT,
	&pdev->dev, dev_name(&pdev->dev), devflags);

	dev_set_drvdata(&pdev->dev, hcd);

	if (IS_ERR(hcd)) {
	pr_warning("isp1760: Failed to register the HCD device\n");
	ret = -ENODEV;
	goto cleanup;
	}

	pr_info("ISP1760 USB device initialised\n");
	return ret;

	cleanup:
	release_mem_region(mem_res->start, mem_size);
	out:
	return ret;
	}

	static int __devexit isp1760_plat_remove(struct platform_device *pdev)
	{
	struct resource *mem_res;
	resource_size_t mem_size;
	struct usb_hcd *hcd = dev_get_drvdata(&pdev->dev);

	usb_remove_hcd(hcd);

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	mem_size = resource_size(mem_res);
	release_mem_region(mem_res->start, mem_size);

	usb_put_hcd(hcd);

	return 0;
	}

	static struct platform_driver isp1760_plat_driver = {
	.probe = isp1760_plat_probe,
	.remove = __devexit_p(isp1760_plat_remove),
	.driver = {
	.name = "isp1760",
	},
	};

	static int __init isp1760_init(void)
	{
	int ret, any_ret = -ENODEV;

	init_kmem_once();

	ret = platform_driver_register(&isp1760_plat_driver);
	if (!ret)
	any_ret = 0;
	#if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
	ret = platform_driver_register(&isp1760_of_driver);
	if (!ret)
	any_ret = 0;
	#endif
	#ifdef CONFIG_PCI
	ret = pci_register_driver(&isp1761_pci_driver);
	if (!ret)
	any_ret = 0;
	#endif

	if (any_ret)
	deinit_kmem_cache();
	return any_ret;
	}
	module_init(isp1760_init);

	static void __exit isp1760_exit(void)
	{
	platform_driver_unregister(&isp1760_plat_driver);
	#if defined(CONFIG_OF) && defined(CONFIG_OF_IRQ)
	platform_driver_unregister(&isp1760_of_driver);
	#endif
	#ifdef CONFIG_PCI
	pci_unregister_driver(&isp1761_pci_driver);
	#endif
	deinit_kmem_cache();
	}
	module_exit(isp1760_exit);