drivers/usb/chipidea/core.c - kernel/msm-4.9 - Gitiles

 /*
  * core.c - ChipIdea USB IP core family device controller
  *
  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
  *
  * Author: David Lopo
  *
  * 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.
  */

 /*
  * Description: ChipIdea USB IP core family device controller
  *
  * This driver is composed of several blocks:
  * - HW:     hardware interface
  * - DBG:    debug facilities (optional)
  * - UTIL:   utilities
  * - ISR:    interrupts handling
  * - ENDPT:  endpoint operations (Gadget API)
  * - GADGET: gadget operations (Gadget API)
  * - BUS:    bus glue code, bus abstraction layer
  *
  * Compile Options
  * - CONFIG_USB_GADGET_DEBUG_FILES: enable debug facilities
  * - STALL_IN:  non-empty bulk-in pipes cannot be halted
  *              if defined mass storage compliance succeeds but with warnings
  *              => case 4: Hi >  Dn
  *              => case 5: Hi >  Di
  *              => case 8: Hi <> Do
  *              if undefined usbtest 13 fails
  * - TRACE:     enable function tracing (depends on DEBUG)
  *
  * Main Features
  * - Chapter 9 & Mass Storage Compliance with Gadget File Storage
  * - Chapter 9 Compliance with Gadget Zero (STALL_IN undefined)
  * - Normal & LPM support
  *
  * USBTEST Report
  * - OK: 0-12, 13 (STALL_IN defined) & 14
  * - Not Supported: 15 & 16 (ISO)
  *
  * TODO List
  * - OTG
  * - Isochronous & Interrupt Traffic
  * - Handle requests which spawns into several TDs
  * - GET_STATUS(device) - always reports 0
  * - Gadget API (majority of optional features)
  * - Suspend & Remote Wakeup
  */
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/dmapool.h>
 #include <linux/dma-mapping.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/idr.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
 #include <linux/usb/otg.h>
 #include <linux/usb/chipidea.h>

 #include "ci.h"
 #include "udc.h"
 #include "bits.h"
 #include "host.h"
 #include "debug.h"

 /* Controller register map */
 static uintptr_t ci_regs_nolpm[] = {
 	[CAP_CAPLENGTH]		= 0x000UL,
 	[CAP_HCCPARAMS]		= 0x008UL,
 	[CAP_DCCPARAMS]		= 0x024UL,
 	[CAP_TESTMODE]		= 0x038UL,
 	[OP_USBCMD]		= 0x000UL,
 	[OP_USBSTS]		= 0x004UL,
 	[OP_USBINTR]		= 0x008UL,
 	[OP_DEVICEADDR]		= 0x014UL,
 	[OP_ENDPTLISTADDR]	= 0x018UL,
 	[OP_PORTSC]		= 0x044UL,
 	[OP_DEVLC]		= 0x084UL,
 	[OP_OTGSC]		= 0x064UL,
 	[OP_USBMODE]		= 0x068UL,
 	[OP_ENDPTSETUPSTAT]	= 0x06CUL,
 	[OP_ENDPTPRIME]		= 0x070UL,
 	[OP_ENDPTFLUSH]		= 0x074UL,
 	[OP_ENDPTSTAT]		= 0x078UL,
 	[OP_ENDPTCOMPLETE]	= 0x07CUL,
 	[OP_ENDPTCTRL]		= 0x080UL,
 };

 static uintptr_t ci_regs_lpm[] = {
 	[CAP_CAPLENGTH]		= 0x000UL,
 	[CAP_HCCPARAMS]		= 0x008UL,
 	[CAP_DCCPARAMS]		= 0x024UL,
 	[CAP_TESTMODE]		= 0x0FCUL,
 	[OP_USBCMD]		= 0x000UL,
 	[OP_USBSTS]		= 0x004UL,
 	[OP_USBINTR]		= 0x008UL,
 	[OP_DEVICEADDR]		= 0x014UL,
 	[OP_ENDPTLISTADDR]	= 0x018UL,
 	[OP_PORTSC]		= 0x044UL,
 	[OP_DEVLC]		= 0x084UL,
 	[OP_OTGSC]		= 0x0C4UL,
 	[OP_USBMODE]		= 0x0C8UL,
 	[OP_ENDPTSETUPSTAT]	= 0x0D8UL,
 	[OP_ENDPTPRIME]		= 0x0DCUL,
 	[OP_ENDPTFLUSH]		= 0x0E0UL,
 	[OP_ENDPTSTAT]		= 0x0E4UL,
 	[OP_ENDPTCOMPLETE]	= 0x0E8UL,
 	[OP_ENDPTCTRL]		= 0x0ECUL,
 };

 static int hw_alloc_regmap(struct ci13xxx *ci, bool is_lpm)
 {
 	int i;

 	kfree(ci->hw_bank.regmap);

 	ci->hw_bank.regmap = kzalloc((OP_LAST + 1) * sizeof(void *),
 				     GFP_KERNEL);
 	if (!ci->hw_bank.regmap)
 		return -ENOMEM;

 	for (i = 0; i < OP_ENDPTCTRL; i++)
 		ci->hw_bank.regmap[i] =
 			(i <= CAP_LAST ? ci->hw_bank.cap : ci->hw_bank.op) +
 			(is_lpm ? ci_regs_lpm[i] : ci_regs_nolpm[i]);

 	for (; i <= OP_LAST; i++)
 		ci->hw_bank.regmap[i] = ci->hw_bank.op +
 			4 * (i - OP_ENDPTCTRL) +
 			(is_lpm
 			 ? ci_regs_lpm[OP_ENDPTCTRL]
 			 : ci_regs_nolpm[OP_ENDPTCTRL]);

 	return 0;
 }

 /**
  * hw_port_test_set: writes port test mode (execute without interruption)
  * @mode: new value
  *
  * This function returns an error code
  */
 int hw_port_test_set(struct ci13xxx *ci, u8 mode)
 {
 	const u8 TEST_MODE_MAX = 7;

 	if (mode > TEST_MODE_MAX)
 		return -EINVAL;

 	hw_write(ci, OP_PORTSC, PORTSC_PTC, mode << ffs_nr(PORTSC_PTC));
 	return 0;
 }

 /**
  * hw_port_test_get: reads port test mode value
  *
  * This function returns port test mode value
  */
 u8 hw_port_test_get(struct ci13xxx *ci)
 {
 	return hw_read(ci, OP_PORTSC, PORTSC_PTC) >> ffs_nr(PORTSC_PTC);
 }

 static int hw_device_init(struct ci13xxx *ci, void __iomem *base)
 {
 	u32 reg;

 	/* bank is a module variable */
 	ci->hw_bank.abs = base;

 	ci->hw_bank.cap = ci->hw_bank.abs;
 	ci->hw_bank.cap += ci->platdata->capoffset;
 	ci->hw_bank.op = ci->hw_bank.cap + ioread8(ci->hw_bank.cap);

 	hw_alloc_regmap(ci, false);
 	reg = hw_read(ci, CAP_HCCPARAMS, HCCPARAMS_LEN) >>
 		ffs_nr(HCCPARAMS_LEN);
 	ci->hw_bank.lpm  = reg;
 	hw_alloc_regmap(ci, !!reg);
 	ci->hw_bank.size = ci->hw_bank.op - ci->hw_bank.abs;
 	ci->hw_bank.size += OP_LAST;
 	ci->hw_bank.size /= sizeof(u32);

 	reg = hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DEN) >>
 		ffs_nr(DCCPARAMS_DEN);
 	ci->hw_ep_max = reg * 2;   /* cache hw ENDPT_MAX */

 	if (ci->hw_ep_max > ENDPT_MAX)
 		return -ENODEV;

 	dev_dbg(ci->dev, "ChipIdea HDRC found, lpm: %d; cap: %p op: %p\n",
 		ci->hw_bank.lpm, ci->hw_bank.cap, ci->hw_bank.op);

 	/* setup lock mode ? */

 	/* ENDPTSETUPSTAT is '0' by default */

 	/* HCSPARAMS.bf.ppc SHOULD BE zero for device */

 	return 0;
 }

 /**
  * hw_device_reset: resets chip (execute without interruption)
  * @ci: the controller
   *
  * This function returns an error code
  */
 int hw_device_reset(struct ci13xxx *ci, u32 mode)
 {
 	/* should flush & stop before reset */
 	hw_write(ci, OP_ENDPTFLUSH, ~0, ~0);
 	hw_write(ci, OP_USBCMD, USBCMD_RS, 0);

 	hw_write(ci, OP_USBCMD, USBCMD_RST, USBCMD_RST);
 	while (hw_read(ci, OP_USBCMD, USBCMD_RST))
 		udelay(10);		/* not RTOS friendly */


 	if (ci->platdata->notify_event)
 		ci->platdata->notify_event(ci,
 			CI13XXX_CONTROLLER_RESET_EVENT);

 	if (ci->platdata->flags & CI13XXX_DISABLE_STREAMING)
 		hw_write(ci, OP_USBMODE, USBMODE_CI_SDIS, USBMODE_CI_SDIS);

 	/* USBMODE should be configured step by step */
 	hw_write(ci, OP_USBMODE, USBMODE_CM, USBMODE_CM_IDLE);
 	hw_write(ci, OP_USBMODE, USBMODE_CM, mode);
 	/* HW >= 2.3 */
 	hw_write(ci, OP_USBMODE, USBMODE_SLOM, USBMODE_SLOM);

 	if (hw_read(ci, OP_USBMODE, USBMODE_CM) != mode) {
 		pr_err("cannot enter in %s mode", ci_role(ci)->name);
 		pr_err("lpm = %i", ci->hw_bank.lpm);
 		return -ENODEV;
 	}

 	return 0;
 }

 /**
  * ci_otg_role - pick role based on ID pin state
  * @ci: the controller
  */
 static enum ci_role ci_otg_role(struct ci13xxx *ci)
 {
 	u32 sts = hw_read(ci, OP_OTGSC, ~0);
 	enum ci_role role = sts & OTGSC_ID
 		? CI_ROLE_GADGET
 		: CI_ROLE_HOST;

 	return role;
 }

 /**
  * ci_role_work - perform role changing based on ID pin
  * @work: work struct
  */
 static void ci_role_work(struct work_struct *work)
 {
 	struct ci13xxx *ci = container_of(work, struct ci13xxx, work);
 	enum ci_role role = ci_otg_role(ci);

 	hw_write(ci, OP_OTGSC, OTGSC_IDIS, OTGSC_IDIS);

 	if (role != ci->role) {
 		dev_dbg(ci->dev, "switching from %s to %s\n",
 			ci_role(ci)->name, ci->roles[role]->name);

 		ci_role_stop(ci);
 		ci_role_start(ci, role);
 	}
 }

 static ssize_t show_role(struct device *dev, struct device_attribute *attr,
 			 char *buf)
 {
 	struct ci13xxx *ci = dev_get_drvdata(dev);

 	return sprintf(buf, "%s\n", ci_role(ci)->name);
 }

 static ssize_t store_role(struct device *dev, struct device_attribute *attr,
 			  const char *buf, size_t count)
 {
 	struct ci13xxx *ci = dev_get_drvdata(dev);
 	enum ci_role role;
 	int ret;

 	for (role = CI_ROLE_HOST; role < CI_ROLE_END; role++)
 		if (ci->roles[role] && !strcmp(buf, ci->roles[role]->name))
 			break;

 	if (role == CI_ROLE_END || role == ci->role)
 		return -EINVAL;

 	ci_role_stop(ci);
 	ret = ci_role_start(ci, role);
 	if (ret)
 		return ret;

 	return count;
 }

 static DEVICE_ATTR(role, S_IRUSR | S_IWUSR, show_role, store_role);

 static irqreturn_t ci_irq(int irq, void *data)
 {
 	struct ci13xxx *ci = data;
 	irqreturn_t ret = IRQ_NONE;

 	if (ci->is_otg) {
 		u32 sts = hw_read(ci, OP_OTGSC, ~0);

 		if (sts & OTGSC_IDIS) {
 			queue_work(ci->wq, &ci->work);
 			ret = IRQ_HANDLED;
 		}
 	}

 	return ci->role == CI_ROLE_END ? ret : ci_role(ci)->irq(ci);
 }

 static DEFINE_IDA(ci_ida);

 struct platform_device *ci13xxx_add_device(struct device *dev,
 			struct resource *res, int nres,
 			struct ci13xxx_platform_data *platdata)
 {
 	struct platform_device *pdev;
 	int id, ret;

 	id = ida_simple_get(&ci_ida, 0, 0, GFP_KERNEL);
 	if (id < 0)
 		return ERR_PTR(id);

 	pdev = platform_device_alloc("ci_hdrc", id);
 	if (!pdev) {
 		ret = -ENOMEM;
 		goto put_id;
 	}

 	pdev->dev.parent = dev;
 	pdev->dev.dma_mask = dev->dma_mask;
 	pdev->dev.dma_parms = dev->dma_parms;
 	dma_set_coherent_mask(&pdev->dev, dev->coherent_dma_mask);

 	ret = platform_device_add_resources(pdev, res, nres);
 	if (ret)
 		goto err;

 	ret = platform_device_add_data(pdev, platdata, sizeof(*platdata));
 	if (ret)
 		goto err;

 	ret = platform_device_add(pdev);
 	if (ret)
 		goto err;

 	return pdev;

 err:
 	platform_device_put(pdev);
 put_id:
 	ida_simple_remove(&ci_ida, id);
 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(ci13xxx_add_device);

 void ci13xxx_remove_device(struct platform_device *pdev)
 {
 	platform_device_unregister(pdev);
 	ida_simple_remove(&ci_ida, pdev->id);
 }
 EXPORT_SYMBOL_GPL(ci13xxx_remove_device);

 static int __devinit ci_hdrc_probe(struct platform_device *pdev)
 {
 	struct device	*dev = &pdev->dev;
 	struct ci13xxx	*ci;
 	struct resource	*res;
 	void __iomem	*base;
 	int		ret;

 	if (!dev->platform_data) {
 		dev_err(dev, "platform data missing\n");
 		return -ENODEV;
 	}

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(dev, "missing resource\n");
 		return -ENODEV;
 	}

 	base = devm_request_and_ioremap(dev, res);
 	if (!res) {
 		dev_err(dev, "can't request and ioremap resource\n");
 		return -ENOMEM;
 	}

 	ci = devm_kzalloc(dev, sizeof(*ci), GFP_KERNEL);
 	if (!ci) {
 		dev_err(dev, "can't allocate device\n");
 		return -ENOMEM;
 	}

 	ci->dev = dev;
 	ci->platdata = dev->platform_data;
 	if (ci->platdata->phy)
 		ci->transceiver = ci->platdata->phy;
 	else
 		ci->global_phy = true;

 	ret = hw_device_init(ci, base);
 	if (ret < 0) {
 		dev_err(dev, "can't initialize hardware\n");
 		return -ENODEV;
 	}

 	ci->hw_bank.phys = res->start;

 	ci->irq = platform_get_irq(pdev, 0);
 	if (ci->irq < 0) {
 		dev_err(dev, "missing IRQ\n");
 		return -ENODEV;
 	}

 	INIT_WORK(&ci->work, ci_role_work);
 	ci->wq = create_singlethread_workqueue("ci_otg");
 	if (!ci->wq) {
 		dev_err(dev, "can't create workqueue\n");
 		return -ENODEV;
 	}

 	/* initialize role(s) before the interrupt is requested */
 	ret = ci_hdrc_host_init(ci);
 	if (ret)
 		dev_info(dev, "doesn't support host\n");

 	ret = ci_hdrc_gadget_init(ci);
 	if (ret)
 		dev_info(dev, "doesn't support gadget\n");

 	if (!ci->roles[CI_ROLE_HOST] && !ci->roles[CI_ROLE_GADGET]) {
 		dev_err(dev, "no supported roles\n");
 		ret = -ENODEV;
 		goto rm_wq;
 	}

 	if (ci->roles[CI_ROLE_HOST] && ci->roles[CI_ROLE_GADGET]) {
 		ci->is_otg = true;
 		ci->role = ci_otg_role(ci);
 	} else {
 		ci->role = ci->roles[CI_ROLE_HOST]
 			? CI_ROLE_HOST
 			: CI_ROLE_GADGET;
 	}

 	ret = ci_role_start(ci, ci->role);
 	if (ret) {
 		dev_err(dev, "can't start %s role\n", ci_role(ci)->name);
 		ret = -ENODEV;
 		goto rm_wq;
 	}

 	platform_set_drvdata(pdev, ci);
 	ret = request_irq(ci->irq, ci_irq, IRQF_SHARED, ci->platdata->name,
 			  ci);
 	if (ret)
 		goto stop;

 	ret = device_create_file(dev, &dev_attr_role);
 	if (ret)
 		goto rm_attr;

 	if (ci->is_otg)
 		hw_write(ci, OP_OTGSC, OTGSC_IDIE, OTGSC_IDIE);

 	return ret;

 rm_attr:
 	device_remove_file(dev, &dev_attr_role);
 stop:
 	ci_role_stop(ci);
 rm_wq:
 	flush_workqueue(ci->wq);
 	destroy_workqueue(ci->wq);

 	return ret;
 }

 static int __devexit ci_hdrc_remove(struct platform_device *pdev)
 {
 	struct ci13xxx *ci = platform_get_drvdata(pdev);

 	flush_workqueue(ci->wq);
 	destroy_workqueue(ci->wq);
 	device_remove_file(ci->dev, &dev_attr_role);
 	free_irq(ci->irq, ci);
 	ci_role_stop(ci);

 	return 0;
 }

 static struct platform_driver ci_hdrc_driver = {
 	.probe	= ci_hdrc_probe,
 	.remove	= __devexit_p(ci_hdrc_remove),
 	.driver	= {
 		.name	= "ci_hdrc",
 	},
 };

 module_platform_driver(ci_hdrc_driver);

 MODULE_ALIAS("platform:ci_hdrc");
 MODULE_ALIAS("platform:ci13xxx");
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("David Lopo <dlopo@chipidea.mips.com>");
 MODULE_DESCRIPTION("ChipIdea HDRC Driver");
	/*
	* core.c - ChipIdea USB IP core family device controller
	*
	* Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
	*
	* Author: David Lopo
	*
	* 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.
	*/

	/*
	* Description: ChipIdea USB IP core family device controller
	*
	* This driver is composed of several blocks:
	* - HW: hardware interface
	* - DBG: debug facilities (optional)
	* - UTIL: utilities
	* - ISR: interrupts handling
	* - ENDPT: endpoint operations (Gadget API)
	* - GADGET: gadget operations (Gadget API)
	* - BUS: bus glue code, bus abstraction layer
	*
	* Compile Options
	* - CONFIG_USB_GADGET_DEBUG_FILES: enable debug facilities
	* - STALL_IN: non-empty bulk-in pipes cannot be halted
	* if defined mass storage compliance succeeds but with warnings
	* => case 4: Hi > Dn
	* => case 5: Hi > Di
	* => case 8: Hi <> Do
	* if undefined usbtest 13 fails
	* - TRACE: enable function tracing (depends on DEBUG)
	*
	* Main Features
	* - Chapter 9 & Mass Storage Compliance with Gadget File Storage
	* - Chapter 9 Compliance with Gadget Zero (STALL_IN undefined)
	* - Normal & LPM support
	*
	* USBTEST Report
	* - OK: 0-12, 13 (STALL_IN defined) & 14
	* - Not Supported: 15 & 16 (ISO)
	*
	* TODO List
	* - OTG
	* - Isochronous & Interrupt Traffic
	* - Handle requests which spawns into several TDs
	* - GET_STATUS(device) - always reports 0
	* - Gadget API (majority of optional features)
	* - Suspend & Remote Wakeup
	*/
	#include <linux/delay.h>
	#include <linux/device.h>
	#include <linux/dmapool.h>
	#include <linux/dma-mapping.h>
	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/module.h>
	#include <linux/idr.h>
	#include <linux/interrupt.h>
	#include <linux/io.h>
	#include <linux/irq.h>
	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/pm_runtime.h>
	#include <linux/usb/ch9.h>
	#include <linux/usb/gadget.h>
	#include <linux/usb/otg.h>
	#include <linux/usb/chipidea.h>

	#include "ci.h"
	#include "udc.h"
	#include "bits.h"
	#include "host.h"
	#include "debug.h"

	/* Controller register map */
	static uintptr_t ci_regs_nolpm[] = {
	[CAP_CAPLENGTH] = 0x000UL,
	[CAP_HCCPARAMS] = 0x008UL,
	[CAP_DCCPARAMS] = 0x024UL,
	[CAP_TESTMODE] = 0x038UL,
	[OP_USBCMD] = 0x000UL,
	[OP_USBSTS] = 0x004UL,
	[OP_USBINTR] = 0x008UL,
	[OP_DEVICEADDR] = 0x014UL,
	[OP_ENDPTLISTADDR] = 0x018UL,
	[OP_PORTSC] = 0x044UL,
	[OP_DEVLC] = 0x084UL,
	[OP_OTGSC] = 0x064UL,
	[OP_USBMODE] = 0x068UL,
	[OP_ENDPTSETUPSTAT] = 0x06CUL,
	[OP_ENDPTPRIME] = 0x070UL,
	[OP_ENDPTFLUSH] = 0x074UL,
	[OP_ENDPTSTAT] = 0x078UL,
	[OP_ENDPTCOMPLETE] = 0x07CUL,
	[OP_ENDPTCTRL] = 0x080UL,
	};

	static uintptr_t ci_regs_lpm[] = {
	[CAP_CAPLENGTH] = 0x000UL,
	[CAP_HCCPARAMS] = 0x008UL,
	[CAP_DCCPARAMS] = 0x024UL,
	[CAP_TESTMODE] = 0x0FCUL,
	[OP_USBCMD] = 0x000UL,
	[OP_USBSTS] = 0x004UL,
	[OP_USBINTR] = 0x008UL,
	[OP_DEVICEADDR] = 0x014UL,
	[OP_ENDPTLISTADDR] = 0x018UL,
	[OP_PORTSC] = 0x044UL,
	[OP_DEVLC] = 0x084UL,
	[OP_OTGSC] = 0x0C4UL,
	[OP_USBMODE] = 0x0C8UL,
	[OP_ENDPTSETUPSTAT] = 0x0D8UL,
	[OP_ENDPTPRIME] = 0x0DCUL,
	[OP_ENDPTFLUSH] = 0x0E0UL,
	[OP_ENDPTSTAT] = 0x0E4UL,
	[OP_ENDPTCOMPLETE] = 0x0E8UL,
	[OP_ENDPTCTRL] = 0x0ECUL,
	};

	static int hw_alloc_regmap(struct ci13xxx *ci, bool is_lpm)
	{
	int i;

	kfree(ci->hw_bank.regmap);

	ci->hw_bank.regmap = kzalloc((OP_LAST + 1) * sizeof(void *),
	GFP_KERNEL);
	if (!ci->hw_bank.regmap)
	return -ENOMEM;

	for (i = 0; i < OP_ENDPTCTRL; i++)
	ci->hw_bank.regmap[i] =
	(i <= CAP_LAST ? ci->hw_bank.cap : ci->hw_bank.op) +
	(is_lpm ? ci_regs_lpm[i] : ci_regs_nolpm[i]);

	for (; i <= OP_LAST; i++)
	ci->hw_bank.regmap[i] = ci->hw_bank.op +
	4 * (i - OP_ENDPTCTRL) +
	(is_lpm
	? ci_regs_lpm[OP_ENDPTCTRL]
	: ci_regs_nolpm[OP_ENDPTCTRL]);

	return 0;
	}

	/**
	* hw_port_test_set: writes port test mode (execute without interruption)
	* @mode: new value
	*
	* This function returns an error code
	*/
	int hw_port_test_set(struct ci13xxx *ci, u8 mode)
	{
	const u8 TEST_MODE_MAX = 7;

	if (mode > TEST_MODE_MAX)
	return -EINVAL;

	hw_write(ci, OP_PORTSC, PORTSC_PTC, mode << ffs_nr(PORTSC_PTC));
	return 0;
	}

	/**
	* hw_port_test_get: reads port test mode value
	*
	* This function returns port test mode value
	*/
	u8 hw_port_test_get(struct ci13xxx *ci)
	{
	return hw_read(ci, OP_PORTSC, PORTSC_PTC) >> ffs_nr(PORTSC_PTC);
	}

	static int hw_device_init(struct ci13xxx ci, void __iomem base)
	{
	u32 reg;

	/* bank is a module variable */
	ci->hw_bank.abs = base;

	ci->hw_bank.cap = ci->hw_bank.abs;
	ci->hw_bank.cap += ci->platdata->capoffset;
	ci->hw_bank.op = ci->hw_bank.cap + ioread8(ci->hw_bank.cap);

	hw_alloc_regmap(ci, false);
	reg = hw_read(ci, CAP_HCCPARAMS, HCCPARAMS_LEN) >>
	ffs_nr(HCCPARAMS_LEN);
	ci->hw_bank.lpm = reg;
	hw_alloc_regmap(ci, !!reg);
	ci->hw_bank.size = ci->hw_bank.op - ci->hw_bank.abs;
	ci->hw_bank.size += OP_LAST;
	ci->hw_bank.size /= sizeof(u32);

	reg = hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DEN) >>
	ffs_nr(DCCPARAMS_DEN);
	ci->hw_ep_max = reg * 2; /* cache hw ENDPT_MAX */

	if (ci->hw_ep_max > ENDPT_MAX)
	return -ENODEV;

	dev_dbg(ci->dev, "ChipIdea HDRC found, lpm: %d; cap: %p op: %p\n",
	ci->hw_bank.lpm, ci->hw_bank.cap, ci->hw_bank.op);

	/* setup lock mode ? */

	/* ENDPTSETUPSTAT is '0' by default */

	/* HCSPARAMS.bf.ppc SHOULD BE zero for device */

	return 0;
	}

	/**
	* hw_device_reset: resets chip (execute without interruption)
	* @ci: the controller
	*
	* This function returns an error code
	*/
	int hw_device_reset(struct ci13xxx *ci, u32 mode)
	{
	/* should flush & stop before reset */
	hw_write(ci, OP_ENDPTFLUSH, ~0, ~0);
	hw_write(ci, OP_USBCMD, USBCMD_RS, 0);

	hw_write(ci, OP_USBCMD, USBCMD_RST, USBCMD_RST);
	while (hw_read(ci, OP_USBCMD, USBCMD_RST))
	udelay(10); /* not RTOS friendly */


	if (ci->platdata->notify_event)
	ci->platdata->notify_event(ci,
	CI13XXX_CONTROLLER_RESET_EVENT);

	if (ci->platdata->flags & CI13XXX_DISABLE_STREAMING)
	hw_write(ci, OP_USBMODE, USBMODE_CI_SDIS, USBMODE_CI_SDIS);

	/* USBMODE should be configured step by step */
	hw_write(ci, OP_USBMODE, USBMODE_CM, USBMODE_CM_IDLE);
	hw_write(ci, OP_USBMODE, USBMODE_CM, mode);
	/* HW >= 2.3 */
	hw_write(ci, OP_USBMODE, USBMODE_SLOM, USBMODE_SLOM);

	if (hw_read(ci, OP_USBMODE, USBMODE_CM) != mode) {
	pr_err("cannot enter in %s mode", ci_role(ci)->name);
	pr_err("lpm = %i", ci->hw_bank.lpm);
	return -ENODEV;
	}

	return 0;
	}

	/**
	* ci_otg_role - pick role based on ID pin state
	* @ci: the controller
	*/
	static enum ci_role ci_otg_role(struct ci13xxx *ci)
	{
	u32 sts = hw_read(ci, OP_OTGSC, ~0);
	enum ci_role role = sts & OTGSC_ID
	? CI_ROLE_GADGET
	: CI_ROLE_HOST;

	return role;
	}

	/**
	* ci_role_work - perform role changing based on ID pin
	* @work: work struct
	*/
	static void ci_role_work(struct work_struct *work)
	{
	struct ci13xxx *ci = container_of(work, struct ci13xxx, work);
	enum ci_role role = ci_otg_role(ci);

	hw_write(ci, OP_OTGSC, OTGSC_IDIS, OTGSC_IDIS);

	if (role != ci->role) {
	dev_dbg(ci->dev, "switching from %s to %s\n",
	ci_role(ci)->name, ci->roles[role]->name);

	ci_role_stop(ci);
	ci_role_start(ci, role);
	}
	}

	static ssize_t show_role(struct device dev, struct device_attribute attr,
	char *buf)
	{
	struct ci13xxx *ci = dev_get_drvdata(dev);

	return sprintf(buf, "%s\n", ci_role(ci)->name);
	}

	static ssize_t store_role(struct device dev, struct device_attribute attr,
	const char *buf, size_t count)
	{
	struct ci13xxx *ci = dev_get_drvdata(dev);
	enum ci_role role;
	int ret;

	for (role = CI_ROLE_HOST; role < CI_ROLE_END; role++)
	if (ci->roles[role] && !strcmp(buf, ci->roles[role]->name))
	break;

	if (role == CI_ROLE_END \|\| role == ci->role)
	return -EINVAL;

	ci_role_stop(ci);
	ret = ci_role_start(ci, role);
	if (ret)
	return ret;

	return count;
	}

	static DEVICE_ATTR(role, S_IRUSR \| S_IWUSR, show_role, store_role);

	static irqreturn_t ci_irq(int irq, void *data)
	{
	struct ci13xxx *ci = data;
	irqreturn_t ret = IRQ_NONE;

	if (ci->is_otg) {
	u32 sts = hw_read(ci, OP_OTGSC, ~0);

	if (sts & OTGSC_IDIS) {
	queue_work(ci->wq, &ci->work);
	ret = IRQ_HANDLED;
	}
	}

	return ci->role == CI_ROLE_END ? ret : ci_role(ci)->irq(ci);
	}

	static DEFINE_IDA(ci_ida);

	struct platform_device ci13xxx_add_device(struct device dev,
	struct resource *res, int nres,
	struct ci13xxx_platform_data *platdata)
	{
	struct platform_device *pdev;
	int id, ret;

	id = ida_simple_get(&ci_ida, 0, 0, GFP_KERNEL);
	if (id < 0)
	return ERR_PTR(id);

	pdev = platform_device_alloc("ci_hdrc", id);
	if (!pdev) {
	ret = -ENOMEM;
	goto put_id;
	}

	pdev->dev.parent = dev;
	pdev->dev.dma_mask = dev->dma_mask;
	pdev->dev.dma_parms = dev->dma_parms;
	dma_set_coherent_mask(&pdev->dev, dev->coherent_dma_mask);

	ret = platform_device_add_resources(pdev, res, nres);
	if (ret)
	goto err;

	ret = platform_device_add_data(pdev, platdata, sizeof(*platdata));
	if (ret)
	goto err;

	ret = platform_device_add(pdev);
	if (ret)
	goto err;

	return pdev;

	err:
	platform_device_put(pdev);
	put_id:
	ida_simple_remove(&ci_ida, id);
	return ERR_PTR(ret);
	}
	EXPORT_SYMBOL_GPL(ci13xxx_add_device);

	void ci13xxx_remove_device(struct platform_device *pdev)
	{
	platform_device_unregister(pdev);
	ida_simple_remove(&ci_ida, pdev->id);
	}
	EXPORT_SYMBOL_GPL(ci13xxx_remove_device);

	static int __devinit ci_hdrc_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct ci13xxx *ci;
	struct resource *res;
	void __iomem *base;
	int ret;

	if (!dev->platform_data) {
	dev_err(dev, "platform data missing\n");
	return -ENODEV;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
	dev_err(dev, "missing resource\n");
	return -ENODEV;
	}

	base = devm_request_and_ioremap(dev, res);
	if (!res) {
	dev_err(dev, "can't request and ioremap resource\n");
	return -ENOMEM;
	}

	ci = devm_kzalloc(dev, sizeof(*ci), GFP_KERNEL);
	if (!ci) {
	dev_err(dev, "can't allocate device\n");
	return -ENOMEM;
	}

	ci->dev = dev;
	ci->platdata = dev->platform_data;
	if (ci->platdata->phy)
	ci->transceiver = ci->platdata->phy;
	else
	ci->global_phy = true;

	ret = hw_device_init(ci, base);
	if (ret < 0) {
	dev_err(dev, "can't initialize hardware\n");
	return -ENODEV;
	}

	ci->hw_bank.phys = res->start;

	ci->irq = platform_get_irq(pdev, 0);
	if (ci->irq < 0) {
	dev_err(dev, "missing IRQ\n");
	return -ENODEV;
	}

	INIT_WORK(&ci->work, ci_role_work);
	ci->wq = create_singlethread_workqueue("ci_otg");
	if (!ci->wq) {
	dev_err(dev, "can't create workqueue\n");
	return -ENODEV;
	}

	/* initialize role(s) before the interrupt is requested */
	ret = ci_hdrc_host_init(ci);
	if (ret)
	dev_info(dev, "doesn't support host\n");

	ret = ci_hdrc_gadget_init(ci);
	if (ret)
	dev_info(dev, "doesn't support gadget\n");

	if (!ci->roles[CI_ROLE_HOST] && !ci->roles[CI_ROLE_GADGET]) {
	dev_err(dev, "no supported roles\n");
	ret = -ENODEV;
	goto rm_wq;
	}

	if (ci->roles[CI_ROLE_HOST] && ci->roles[CI_ROLE_GADGET]) {
	ci->is_otg = true;
	ci->role = ci_otg_role(ci);
	} else {
	ci->role = ci->roles[CI_ROLE_HOST]
	? CI_ROLE_HOST
	: CI_ROLE_GADGET;
	}

	ret = ci_role_start(ci, ci->role);
	if (ret) {
	dev_err(dev, "can't start %s role\n", ci_role(ci)->name);
	ret = -ENODEV;
	goto rm_wq;
	}

	platform_set_drvdata(pdev, ci);
	ret = request_irq(ci->irq, ci_irq, IRQF_SHARED, ci->platdata->name,
	ci);
	if (ret)
	goto stop;

	ret = device_create_file(dev, &dev_attr_role);
	if (ret)
	goto rm_attr;

	if (ci->is_otg)
	hw_write(ci, OP_OTGSC, OTGSC_IDIE, OTGSC_IDIE);

	return ret;

	rm_attr:
	device_remove_file(dev, &dev_attr_role);
	stop:
	ci_role_stop(ci);
	rm_wq:
	flush_workqueue(ci->wq);
	destroy_workqueue(ci->wq);

	return ret;
	}

	static int __devexit ci_hdrc_remove(struct platform_device *pdev)
	{
	struct ci13xxx *ci = platform_get_drvdata(pdev);

	flush_workqueue(ci->wq);
	destroy_workqueue(ci->wq);
	device_remove_file(ci->dev, &dev_attr_role);
	free_irq(ci->irq, ci);
	ci_role_stop(ci);

	return 0;
	}

	static struct platform_driver ci_hdrc_driver = {
	.probe = ci_hdrc_probe,
	.remove = __devexit_p(ci_hdrc_remove),
	.driver = {
	.name = "ci_hdrc",
	},
	};

	module_platform_driver(ci_hdrc_driver);

	MODULE_ALIAS("platform:ci_hdrc");
	MODULE_ALIAS("platform:ci13xxx");
	MODULE_LICENSE("GPL v2");
	MODULE_AUTHOR("David Lopo <dlopo@chipidea.mips.com>");
	MODULE_DESCRIPTION("ChipIdea HDRC Driver");