/*
 * R8A66597 UDC (USB gadget)
 *
 * Copyright (C) 2006-2009 Renesas Solutions Corp.
 *
 * Author : Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/slab.h>

#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>

#include "r8a66597-udc.h"

#define DRIVER_VERSION	"2009-08-18"

static const char udc_name[] = "r8a66597_udc";
static const char *r8a66597_ep_name[] = {
	"ep0", "ep1", "ep2", "ep3", "ep4", "ep5", "ep6", "ep7",
	"ep8", "ep9",
};

static void init_controller(struct r8a66597 *r8a66597);
static void disable_controller(struct r8a66597 *r8a66597);
static void irq_ep0_write(struct r8a66597_ep *ep, struct r8a66597_request *req);
static void irq_packet_write(struct r8a66597_ep *ep,
				struct r8a66597_request *req);
static int r8a66597_queue(struct usb_ep *_ep, struct usb_request *_req,
			gfp_t gfp_flags);

static void transfer_complete(struct r8a66597_ep *ep,
		struct r8a66597_request *req, int status);

/*-------------------------------------------------------------------------*/
static inline u16 get_usb_speed(struct r8a66597 *r8a66597)
{
	return r8a66597_read(r8a66597, DVSTCTR0) & RHST;
}

static void enable_pipe_irq(struct r8a66597 *r8a66597, u16 pipenum,
		unsigned long reg)
{
	u16 tmp;

	tmp = r8a66597_read(r8a66597, INTENB0);
	r8a66597_bclr(r8a66597, BEMPE | NRDYE | BRDYE,
			INTENB0);
	r8a66597_bset(r8a66597, (1 << pipenum), reg);
	r8a66597_write(r8a66597, tmp, INTENB0);
}

static void disable_pipe_irq(struct r8a66597 *r8a66597, u16 pipenum,
		unsigned long reg)
{
	u16 tmp;

	tmp = r8a66597_read(r8a66597, INTENB0);
	r8a66597_bclr(r8a66597, BEMPE | NRDYE | BRDYE,
			INTENB0);
	r8a66597_bclr(r8a66597, (1 << pipenum), reg);
	r8a66597_write(r8a66597, tmp, INTENB0);
}

static void r8a66597_usb_connect(struct r8a66597 *r8a66597)
{
	r8a66597_bset(r8a66597, CTRE, INTENB0);
	r8a66597_bset(r8a66597, BEMPE | BRDYE, INTENB0);

	r8a66597_bset(r8a66597, DPRPU, SYSCFG0);
}

static void r8a66597_usb_disconnect(struct r8a66597 *r8a66597)
__releases(r8a66597->lock)
__acquires(r8a66597->lock)
{
	r8a66597_bclr(r8a66597, CTRE, INTENB0);
	r8a66597_bclr(r8a66597, BEMPE | BRDYE, INTENB0);
	r8a66597_bclr(r8a66597, DPRPU, SYSCFG0);

	r8a66597->gadget.speed = USB_SPEED_UNKNOWN;
	spin_unlock(&r8a66597->lock);
	r8a66597->driver->disconnect(&r8a66597->gadget);
	spin_lock(&r8a66597->lock);

	disable_controller(r8a66597);
	init_controller(r8a66597);
	r8a66597_bset(r8a66597, VBSE, INTENB0);
	INIT_LIST_HEAD(&r8a66597->ep[0].queue);
}

static inline u16 control_reg_get_pid(struct r8a66597 *r8a66597, u16 pipenum)
{
	u16 pid = 0;
	unsigned long offset;

	if (pipenum == 0)
		pid = r8a66597_read(r8a66597, DCPCTR) & PID;
	else if (pipenum < R8A66597_MAX_NUM_PIPE) {
		offset = get_pipectr_addr(pipenum);
		pid = r8a66597_read(r8a66597, offset) & PID;
	} else
		printk(KERN_ERR "unexpect pipe num (%d)\n", pipenum);

	return pid;
}

static inline void control_reg_set_pid(struct r8a66597 *r8a66597, u16 pipenum,
		u16 pid)
{
	unsigned long offset;

	if (pipenum == 0)
		r8a66597_mdfy(r8a66597, pid, PID, DCPCTR);
	else if (pipenum < R8A66597_MAX_NUM_PIPE) {
		offset = get_pipectr_addr(pipenum);
		r8a66597_mdfy(r8a66597, pid, PID, offset);
	} else
		printk(KERN_ERR "unexpect pipe num (%d)\n", pipenum);
}

static inline void pipe_start(struct r8a66597 *r8a66597, u16 pipenum)
{
	control_reg_set_pid(r8a66597, pipenum, PID_BUF);
}

static inline void pipe_stop(struct r8a66597 *r8a66597, u16 pipenum)
{
	control_reg_set_pid(r8a66597, pipenum, PID_NAK);
}

static inline void pipe_stall(struct r8a66597 *r8a66597, u16 pipenum)
{
	control_reg_set_pid(r8a66597, pipenum, PID_STALL);
}

static inline u16 control_reg_get(struct r8a66597 *r8a66597, u16 pipenum)
{
	u16 ret = 0;
	unsigned long offset;

	if (pipenum == 0)
		ret = r8a66597_read(r8a66597, DCPCTR);
	else if (pipenum < R8A66597_MAX_NUM_PIPE) {
		offset = get_pipectr_addr(pipenum);
		ret = r8a66597_read(r8a66597, offset);
	} else
		printk(KERN_ERR "unexpect pipe num (%d)\n", pipenum);

	return ret;
}

static inline void control_reg_sqclr(struct r8a66597 *r8a66597, u16 pipenum)
{
	unsigned long offset;

	pipe_stop(r8a66597, pipenum);

	if (pipenum == 0)
		r8a66597_bset(r8a66597, SQCLR, DCPCTR);
	else if (pipenum < R8A66597_MAX_NUM_PIPE) {
		offset = get_pipectr_addr(pipenum);
		r8a66597_bset(r8a66597, SQCLR, offset);
	} else
		printk(KERN_ERR "unexpect pipe num(%d)\n", pipenum);
}

static inline int get_buffer_size(struct r8a66597 *r8a66597, u16 pipenum)
{
	u16 tmp;
	int size;

	if (pipenum == 0) {
		tmp = r8a66597_read(r8a66597, DCPCFG);
		if ((tmp & R8A66597_CNTMD) != 0)
			size = 256;
		else {
			tmp = r8a66597_read(r8a66597, DCPMAXP);
			size = tmp & MAXP;
		}
	} else {
		r8a66597_write(r8a66597, pipenum, PIPESEL);
		tmp = r8a66597_read(r8a66597, PIPECFG);
		if ((tmp & R8A66597_CNTMD) != 0) {
			tmp = r8a66597_read(r8a66597, PIPEBUF);
			size = ((tmp >> 10) + 1) * 64;
		} else {
			tmp = r8a66597_read(r8a66597, PIPEMAXP);
			size = tmp & MXPS;
		}
	}

	return size;
}

static inline unsigned short mbw_value(struct r8a66597 *r8a66597)
{
	if (r8a66597->pdata->on_chip)
		return MBW_32;
	else
		return MBW_16;
}

static inline void pipe_change(struct r8a66597 *r8a66597, u16 pipenum)
{
	struct r8a66597_ep *ep = r8a66597->pipenum2ep[pipenum];

	if (ep->use_dma)
		return;

	r8a66597_mdfy(r8a66597, pipenum, CURPIPE, ep->fifosel);

	ndelay(450);

	r8a66597_bset(r8a66597, mbw_value(r8a66597), ep->fifosel);
}

static int pipe_buffer_setting(struct r8a66597 *r8a66597,
		struct r8a66597_pipe_info *info)
{
	u16 bufnum = 0, buf_bsize = 0;
	u16 pipecfg = 0;

	if (info->pipe == 0)
		return -EINVAL;

	r8a66597_write(r8a66597, info->pipe, PIPESEL);

	if (info->dir_in)
		pipecfg |= R8A66597_DIR;
	pipecfg |= info->type;
	pipecfg |= info->epnum;
	switch (info->type) {
	case R8A66597_INT:
		bufnum = 4 + (info->pipe - R8A66597_BASE_PIPENUM_INT);
		buf_bsize = 0;
		break;
	case R8A66597_BULK:
		/* isochronous pipes may be used as bulk pipes */
		if (info->pipe >= R8A66597_BASE_PIPENUM_BULK)
			bufnum = info->pipe - R8A66597_BASE_PIPENUM_BULK;
		else
			bufnum = info->pipe - R8A66597_BASE_PIPENUM_ISOC;

		bufnum = R8A66597_BASE_BUFNUM + (bufnum * 16);
		buf_bsize = 7;
		pipecfg |= R8A66597_DBLB;
		if (!info->dir_in)
			pipecfg |= R8A66597_SHTNAK;
		break;
	case R8A66597_ISO:
		bufnum = R8A66597_BASE_BUFNUM +
			 (info->pipe - R8A66597_BASE_PIPENUM_ISOC) * 16;
		buf_bsize = 7;
		break;
	}

	if (buf_bsize && ((bufnum + 16) >= R8A66597_MAX_BUFNUM)) {
		pr_err("r8a66597 pipe memory is insufficient\n");
		return -ENOMEM;
	}

	r8a66597_write(r8a66597, pipecfg, PIPECFG);
	r8a66597_write(r8a66597, (buf_bsize << 10) | (bufnum), PIPEBUF);
	r8a66597_write(r8a66597, info->maxpacket, PIPEMAXP);
	if (info->interval)
		info->interval--;
	r8a66597_write(r8a66597, info->interval, PIPEPERI);

	return 0;
}

static void pipe_buffer_release(struct r8a66597 *r8a66597,
				struct r8a66597_pipe_info *info)
{
	if (info->pipe == 0)
		return;

	if (is_bulk_pipe(info->pipe))
		r8a66597->bulk--;
	else if (is_interrupt_pipe(info->pipe))
		r8a66597->interrupt--;
	else if (is_isoc_pipe(info->pipe)) {
		r8a66597->isochronous--;
		if (info->type == R8A66597_BULK)
			r8a66597->bulk--;
	} else
		printk(KERN_ERR "ep_release: unexpect pipenum (%d)\n",
				info->pipe);
}

static void pipe_initialize(struct r8a66597_ep *ep)
{
	struct r8a66597 *r8a66597 = ep->r8a66597;

	r8a66597_mdfy(r8a66597, 0, CURPIPE, ep->fifosel);

	r8a66597_write(r8a66597, ACLRM, ep->pipectr);
	r8a66597_write(r8a66597, 0, ep->pipectr);
	r8a66597_write(r8a66597, SQCLR, ep->pipectr);
	if (ep->use_dma) {
		r8a66597_mdfy(r8a66597, ep->pipenum, CURPIPE, ep->fifosel);

		ndelay(450);

		r8a66597_bset(r8a66597, mbw_value(r8a66597), ep->fifosel);
	}
}

static void r8a66597_ep_setting(struct r8a66597 *r8a66597,
				struct r8a66597_ep *ep,
				const struct usb_endpoint_descriptor *desc,
				u16 pipenum, int dma)
{
	ep->use_dma = 0;
	ep->fifoaddr = CFIFO;
	ep->fifosel = CFIFOSEL;
	ep->fifoctr = CFIFOCTR;
	ep->fifotrn = 0;

	ep->pipectr = get_pipectr_addr(pipenum);
	ep->pipenum = pipenum;
	ep->ep.maxpacket = le16_to_cpu(desc->wMaxPacketSize);
	r8a66597->pipenum2ep[pipenum] = ep;
	r8a66597->epaddr2ep[desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK]
		= ep;
	INIT_LIST_HEAD(&ep->queue);
}

static void r8a66597_ep_release(struct r8a66597_ep *ep)
{
	struct r8a66597 *r8a66597 = ep->r8a66597;
	u16 pipenum = ep->pipenum;

	if (pipenum == 0)
		return;

	if (ep->use_dma)
		r8a66597->num_dma--;
	ep->pipenum = 0;
	ep->busy = 0;
	ep->use_dma = 0;
}

static int alloc_pipe_config(struct r8a66597_ep *ep,
		const struct usb_endpoint_descriptor *desc)
{
	struct r8a66597 *r8a66597 = ep->r8a66597;
	struct r8a66597_pipe_info info;
	int dma = 0;
	unsigned char *counter;
	int ret;

	ep->desc = desc;

	if (ep->pipenum)	/* already allocated pipe  */
		return 0;

	switch (desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
	case USB_ENDPOINT_XFER_BULK:
		if (r8a66597->bulk >= R8A66597_MAX_NUM_BULK) {
			if (r8a66597->isochronous >= R8A66597_MAX_NUM_ISOC) {
				printk(KERN_ERR "bulk pipe is insufficient\n");
				return -ENODEV;
			} else {
				info.pipe = R8A66597_BASE_PIPENUM_ISOC
						+ r8a66597->isochronous;
				counter = &r8a66597->isochronous;
			}
		} else {
			info.pipe = R8A66597_BASE_PIPENUM_BULK + r8a66597->bulk;
			counter = &r8a66597->bulk;
		}
		info.type = R8A66597_BULK;
		dma = 1;
		break;
	case USB_ENDPOINT_XFER_INT:
		if (r8a66597->interrupt >= R8A66597_MAX_NUM_INT) {
			printk(KERN_ERR "interrupt pipe is insufficient\n");
			return -ENODEV;
		}
		info.pipe = R8A66597_BASE_PIPENUM_INT + r8a66597->interrupt;
		info.type = R8A66597_INT;
		counter = &r8a66597->interrupt;
		break;
	case USB_ENDPOINT_XFER_ISOC:
		if (r8a66597->isochronous >= R8A66597_MAX_NUM_ISOC) {
			printk(KERN_ERR "isochronous pipe is insufficient\n");
			return -ENODEV;
		}
		info.pipe = R8A66597_BASE_PIPENUM_ISOC + r8a66597->isochronous;
		info.type = R8A66597_ISO;
		counter = &r8a66597->isochronous;
		break;
	default:
		printk(KERN_ERR "unexpect xfer type\n");
		return -EINVAL;
	}
	ep->type = info.type;

	info.epnum = desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
	info.maxpacket = le16_to_cpu(desc->wMaxPacketSize);
	info.interval = desc->bInterval;
	if (desc->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
		info.dir_in = 1;
	else
		info.dir_in = 0;

	ret = pipe_buffer_setting(r8a66597, &info);
	if (ret < 0) {
		printk(KERN_ERR "pipe_buffer_setting fail\n");
		return ret;
	}

	(*counter)++;
	if ((counter == &r8a66597->isochronous) && info.type == R8A66597_BULK)
		r8a66597->bulk++;

	r8a66597_ep_setting(r8a66597, ep, desc, info.pipe, dma);
	pipe_initialize(ep);

	return 0;
}

static int free_pipe_config(struct r8a66597_ep *ep)
{
	struct r8a66597 *r8a66597 = ep->r8a66597;
	struct r8a66597_pipe_info info;

	info.pipe = ep->pipenum;
	info.type = ep->type;
	pipe_buffer_release(r8a66597, &info);
	r8a66597_ep_release(ep);

	return 0;
}

/*-------------------------------------------------------------------------*/
static void pipe_irq_enable(struct r8a66597 *r8a66597, u16 pipenum)
{
	enable_irq_ready(r8a66597, pipenum);
	enable_irq_nrdy(r8a66597, pipenum);
}

static void pipe_irq_disable(struct r8a66597 *r8a66597, u16 pipenum)
{
	disable_irq_ready(r8a66597, pipenum);
	disable_irq_nrdy(r8a66597, pipenum);
}

/* if complete is true, gadget driver complete function is not call */
static void control_end(struct r8a66597 *r8a66597, unsigned ccpl)
{
	r8a66597->ep[0].internal_ccpl = ccpl;
	pipe_start(r8a66597, 0);
	r8a66597_bset(r8a66597, CCPL, DCPCTR);
}

static void start_ep0_write(struct r8a66597_ep *ep,
				struct r8a66597_request *req)
{
	struct r8a66597 *r8a66597 = ep->r8a66597;

	pipe_change(r8a66597, ep->pipenum);
	r8a66597_mdfy(r8a66597, ISEL, (ISEL | CURPIPE), CFIFOSEL);
	r8a66597_write(r8a66597, BCLR, ep->fifoctr);
	if (req->req.length == 0) {
		r8a66597_bset(r8a66597, BVAL, ep->fifoctr);
		pipe_start(r8a66597, 0);
		transfer_complete(ep, req, 0);
	} else {
		r8a66597_write(r8a66597, ~BEMP0, BEMPSTS);
		irq_ep0_write(ep, req);
	}
}

static void start_packet_write(struct r8a66597_ep *ep,
				struct r8a66597_request *req)
{
	struct r8a66597 *r8a66597 = ep->r8a66597;
	u16 tmp;

	pipe_change(r8a66597, ep->pipenum);
	disable_irq_empty(r8a66597, ep->pipenum);
	pipe_start(r8a66597, ep->pipenum);

	tmp = r8a66597_read(r8a66597, ep->fifoctr);
	if (unlikely((tmp & FRDY) == 0))
		pipe_irq_enable(r8a66597, ep->pipenum);
	else
		irq_packet_write(ep, req);
}

static void start_packet_read(struct r8a66597_ep *ep,
				struct r8a66597_request *req)
{
	struct r8a66597 *r8a66597 = ep->r8a66597;
	u16 pipenum = ep->pipenum;

	if (ep->pipenum == 0) {
		r8a66597_mdfy(r8a66597, 0, (ISEL | CURPIPE), CFIFOSEL);
		r8a66597_write(r8a66597, BCLR, ep->fifoctr);
		pipe_start(r8a66597, pipenum);
		pipe_irq_enable(r8a66597, pipenum);
	} else {
		if (ep->use_dma) {
			r8a66597_bset(r8a66597, TRCLR, ep->fifosel);
			pipe_change(r8a66597, pipenum);
			r8a66597_bset(r8a66597, TRENB, ep->fifosel);
			r8a66597_write(r8a66597,
				(req->req.length + ep->ep.maxpacket - 1)
					/ ep->ep.maxpacket,
				ep->fifotrn);
		}
		pipe_start(r8a66597, pipenum);	/* trigger once */
		pipe_irq_enable(r8a66597, pipenum);
	}
}

static void start_packet(struct r8a66597_ep *ep, struct r8a66597_request *req)
{
	if (ep->desc->bEndpointAddress & USB_DIR_IN)
		start_packet_write(ep, req);
	else
		start_packet_read(ep, req);
}

static void start_ep0(struct r8a66597_ep *ep, struct r8a66597_request *req)
{
	u16 ctsq;

	ctsq = r8a66597_read(ep->r8a66597, INTSTS0) & CTSQ;

	switch (ctsq) {
	case CS_RDDS:
		start_ep0_write(ep, req);
		break;
	case CS_WRDS:
		start_packet_read(ep, req);
		break;

	case CS_WRND:
		control_end(ep->r8a66597, 0);
		break;
	default:
		printk(KERN_ERR "start_ep0: unexpect ctsq(%x)\n", ctsq);
		break;
	}
}

static void init_controller(struct r8a66597 *r8a66597)
{
	u16 vif = r8a66597->pdata->vif ? LDRV : 0;
	u16 irq_sense = r8a66597->irq_sense_low ? INTL : 0;
	u16 endian = r8a66597->pdata->endian ? BIGEND : 0;

	if (r8a66597->pdata->on_chip) {
		r8a66597_bset(r8a66597, 0x04, SYSCFG1);
		r8a66597_bset(r8a66597, HSE, SYSCFG0);

		r8a66597_bclr(r8a66597, USBE, SYSCFG0);
		r8a66597_bclr(r8a66597, DPRPU, SYSCFG0);
		r8a66597_bset(r8a66597, USBE, SYSCFG0);

		r8a66597_bset(r8a66597, SCKE, SYSCFG0);

		r8a66597_bset(r8a66597, irq_sense, INTENB1);
		r8a66597_write(r8a66597, BURST | CPU_ADR_RD_WR,
				DMA0CFG);
	} else {
		r8a66597_bset(r8a66597, vif | endian, PINCFG);
		r8a66597_bset(r8a66597, HSE, SYSCFG0);		/* High spd */
		r8a66597_mdfy(r8a66597, get_xtal_from_pdata(r8a66597->pdata),
				XTAL, SYSCFG0);

		r8a66597_bclr(r8a66597, USBE, SYSCFG0);
		r8a66597_bclr(r8a66597, DPRPU, SYSCFG0);
		r8a66597_bset(r8a66597, USBE, SYSCFG0);

		r8a66597_bset(r8a66597, XCKE, SYSCFG0);

		msleep(3);

		r8a66597_bset(r8a66597, PLLC, SYSCFG0);

		msleep(1);

		r8a66597_bset(r8a66597, SCKE, SYSCFG0);

		r8a66597_bset(r8a66597, irq_sense, INTENB1);
		r8a66597_write(r8a66597, BURST | CPU_ADR_RD_WR,
			       DMA0CFG);
	}
}

static void disable_controller(struct r8a66597 *r8a66597)
{
	if (r8a66597->pdata->on_chip) {
		r8a66597_bset(r8a66597, SCKE, SYSCFG0);

		/* disable interrupts */
		r8a66597_write(r8a66597, 0, INTENB0);
		r8a66597_write(r8a66597, 0, INTENB1);
		r8a66597_write(r8a66597, 0, BRDYENB);
		r8a66597_write(r8a66597, 0, BEMPENB);
		r8a66597_write(r8a66597, 0, NRDYENB);

		/* clear status */
		r8a66597_write(r8a66597, 0, BRDYSTS);
		r8a66597_write(r8a66597, 0, NRDYSTS);
		r8a66597_write(r8a66597, 0, BEMPSTS);

		r8a66597_bclr(r8a66597, USBE, SYSCFG0);
		r8a66597_bclr(r8a66597, SCKE, SYSCFG0);

	} else {
		r8a66597_bclr(r8a66597, SCKE, SYSCFG0);
		udelay(1);
		r8a66597_bclr(r8a66597, PLLC, SYSCFG0);
		udelay(1);
		udelay(1);
		r8a66597_bclr(r8a66597, XCKE, SYSCFG0);
	}
}

static void r8a66597_start_xclock(struct r8a66597 *r8a66597)
{
	u16 tmp;

	if (!r8a66597->pdata->on_chip) {
		tmp = r8a66597_read(r8a66597, SYSCFG0);
		if (!(tmp & XCKE))
			r8a66597_bset(r8a66597, XCKE, SYSCFG0);
	}
}

static struct r8a66597_request *get_request_from_ep(struct r8a66597_ep *ep)
{
	return list_entry(ep->queue.next, struct r8a66597_request, queue);
}

/*-------------------------------------------------------------------------*/
static void transfer_complete(struct r8a66597_ep *ep,
		struct r8a66597_request *req, int status)
__releases(r8a66597->lock)
__acquires(r8a66597->lock)
{
	int restart = 0;

	if (unlikely(ep->pipenum == 0)) {
		if (ep->internal_ccpl) {
			ep->internal_ccpl = 0;
			return;
		}
	}

	list_del_init(&req->queue);
	if (ep->r8a66597->gadget.speed == USB_SPEED_UNKNOWN)
		req->req.status = -ESHUTDOWN;
	else
		req->req.status = status;

	if (!list_empty(&ep->queue))
		restart = 1;

	spin_unlock(&ep->r8a66597->lock);
	req->req.complete(&ep->ep, &req->req);
	spin_lock(&ep->r8a66597->lock);

	if (restart) {
		req = get_request_from_ep(ep);
		if (ep->desc)
			start_packet(ep, req);
	}
}

static void irq_ep0_write(struct r8a66597_ep *ep, struct r8a66597_request *req)
{
	int i;
	u16 tmp;
	unsigned bufsize;
	size_t size;
	void *buf;
	u16 pipenum = ep->pipenum;
	struct r8a66597 *r8a66597 = ep->r8a66597;

	pipe_change(r8a66597, pipenum);
	r8a66597_bset(r8a66597, ISEL, ep->fifosel);

	i = 0;
	do {
		tmp = r8a66597_read(r8a66597, ep->fifoctr);
		if (i++ > 100000) {
			printk(KERN_ERR "pipe0 is busy. maybe cpu i/o bus"
				"conflict. please power off this controller.");
			return;
		}
		ndelay(1);
	} while ((tmp & FRDY) == 0);

	/* prepare parameters */
	bufsize = get_buffer_size(r8a66597, pipenum);
	buf = req->req.buf + req->req.actual;
	size = min(bufsize, req->req.length - req->req.actual);

	/* write fifo */
	if (req->req.buf) {
		if (size > 0)
			r8a66597_write_fifo(r8a66597, ep->fifoaddr, buf, size);
		if ((size == 0) || ((size % ep->ep.maxpacket) != 0))
			r8a66597_bset(r8a66597, BVAL, ep->fifoctr);
	}

	/* update parameters */
	req->req.actual += size;

	/* check transfer finish */
	if ((!req->req.zero && (req->req.actual == req->req.length))
			|| (size % ep->ep.maxpacket)
			|| (size == 0)) {
		disable_irq_ready(r8a66597, pipenum);
		disable_irq_empty(r8a66597, pipenum);
	} else {
		disable_irq_ready(r8a66597, pipenum);
		enable_irq_empty(r8a66597, pipenum);
	}
	pipe_start(r8a66597, pipenum);
}

static void irq_packet_write(struct r8a66597_ep *ep,
				struct r8a66597_request *req)
{
	u16 tmp;
	unsigned bufsize;
	size_t size;
	void *buf;
	u16 pipenum = ep->pipenum;
	struct r8a66597 *r8a66597 = ep->r8a66597;

	pipe_change(r8a66597, pipenum);
	tmp = r8a66597_read(r8a66597, ep->fifoctr);
	if (unlikely((tmp & FRDY) == 0)) {
		pipe_stop(r8a66597, pipenum);
		pipe_irq_disable(r8a66597, pipenum);
		printk(KERN_ERR "write fifo not ready. pipnum=%d\n", pipenum);
		return;
	}

	/* prepare parameters */
	bufsize = get_buffer_size(r8a66597, pipenum);
	buf = req->req.buf + req->req.actual;
	size = min(bufsize, req->req.length - req->req.actual);

	/* write fifo */
	if (req->req.buf) {
		r8a66597_write_fifo(r8a66597, ep->fifoaddr, buf, size);
		if ((size == 0)
				|| ((size % ep->ep.maxpacket) != 0)
				|| ((bufsize != ep->ep.maxpacket)
					&& (bufsize > size)))
			r8a66597_bset(r8a66597, BVAL, ep->fifoctr);
	}

	/* update parameters */
	req->req.actual += size;
	/* check transfer finish */
	if ((!req->req.zero && (req->req.actual == req->req.length))
			|| (size % ep->ep.maxpacket)
			|| (size == 0)) {
		disable_irq_ready(r8a66597, pipenum);
		enable_irq_empty(r8a66597, pipenum);
	} else {
		disable_irq_empty(r8a66597, pipenum);
		pipe_irq_enable(r8a66597, pipenum);
	}
}

static void irq_packet_read(struct r8a66597_ep *ep,
				struct r8a66597_request *req)
{
	u16 tmp;
	int rcv_len, bufsize, req_len;
	int size;
	void *buf;
	u16 pipenum = ep->pipenum;
	struct r8a66597 *r8a66597 = ep->r8a66597;
	int finish = 0;

	pipe_change(r8a66597, pipenum);
	tmp = r8a66597_read(r8a66597, ep->fifoctr);
	if (unlikely((tmp & FRDY) == 0)) {
		req->req.status = -EPIPE;
		pipe_stop(r8a66597, pipenum);
		pipe_irq_disable(r8a66597, pipenum);
		printk(KERN_ERR "read fifo not ready");
		return;
	}

	/* prepare parameters */
	rcv_len = tmp & DTLN;
	bufsize = get_buffer_size(r8a66597, pipenum);

	buf = req->req.buf + req->req.actual;
	req_len = req->req.length - req->req.actual;
	if (rcv_len < bufsize)
		size = min(rcv_len, req_len);
	else
		size = min(bufsize, req_len);

	/* update parameters */
	req->req.actual += size;

	/* check transfer finish */
	if ((!req->req.zero && (req->req.actual == req->req.length))
			|| (size % ep->ep.maxpacket)
			|| (size == 0)) {
		pipe_stop(r8a66597, pipenum);
		pipe_irq_disable(r8a66597, pipenum);
		finish = 1;
	}

	/* read fifo */
	if (req->req.buf) {
		if (size == 0)
			r8a66597_write(r8a66597, BCLR, ep->fifoctr);
		else
			r8a66597_read_fifo(r8a66597, ep->fifoaddr, buf, size);

	}

	if ((ep->pipenum != 0) && finish)
		transfer_complete(ep, req, 0);
}

static void irq_pipe_ready(struct r8a66597 *r8a66597, u16 status, u16 enb)
{
	u16 check;
	u16 pipenum;
	struct r8a66597_ep *ep;
	struct r8a66597_request *req;

	if ((status & BRDY0) && (enb & BRDY0)) {
		r8a66597_write(r8a66597, ~BRDY0, BRDYSTS);
		r8a66597_mdfy(r8a66597, 0, CURPIPE, CFIFOSEL);

		ep = &r8a66597->ep[0];
		req = get_request_from_ep(ep);
		irq_packet_read(ep, req);
	} else {
		for (pipenum = 1; pipenum < R8A66597_MAX_NUM_PIPE; pipenum++) {
			check = 1 << pipenum;
			if ((status & check) && (enb & check)) {
				r8a66597_write(r8a66597, ~check, BRDYSTS);
				ep = r8a66597->pipenum2ep[pipenum];
				req = get_request_from_ep(ep);
				if (ep->desc->bEndpointAddress & USB_DIR_IN)
					irq_packet_write(ep, req);
				else
					irq_packet_read(ep, req);
			}
		}
	}
}

static void irq_pipe_empty(struct r8a66597 *r8a66597, u16 status, u16 enb)
{
	u16 tmp;
	u16 check;
	u16 pipenum;
	struct r8a66597_ep *ep;
	struct r8a66597_request *req;

	if ((status & BEMP0) && (enb & BEMP0)) {
		r8a66597_write(r8a66597, ~BEMP0, BEMPSTS);

		ep = &r8a66597->ep[0];
		req = get_request_from_ep(ep);
		irq_ep0_write(ep, req);
	} else {
		for (pipenum = 1; pipenum < R8A66597_MAX_NUM_PIPE; pipenum++) {
			check = 1 << pipenum;
			if ((status & check) && (enb & check)) {
				r8a66597_write(r8a66597, ~check, BEMPSTS);
				tmp = control_reg_get(r8a66597, pipenum);
				if ((tmp & INBUFM) == 0) {
					disable_irq_empty(r8a66597, pipenum);
					pipe_irq_disable(r8a66597, pipenum);
					pipe_stop(r8a66597, pipenum);
					ep = r8a66597->pipenum2ep[pipenum];
					req = get_request_from_ep(ep);
					if (!list_empty(&ep->queue))
						transfer_complete(ep, req, 0);
				}
			}
		}
	}
}

static void get_status(struct r8a66597 *r8a66597, struct usb_ctrlrequest *ctrl)
__releases(r8a66597->lock)
__acquires(r8a66597->lock)
{
	struct r8a66597_ep *ep;
	u16 pid;
	u16 status = 0;
	u16 w_index = le16_to_cpu(ctrl->wIndex);

	switch (ctrl->bRequestType & USB_RECIP_MASK) {
	case USB_RECIP_DEVICE:
		status = 1 << USB_DEVICE_SELF_POWERED;
		break;
	case USB_RECIP_INTERFACE:
		status = 0;
		break;
	case USB_RECIP_ENDPOINT:
		ep = r8a66597->epaddr2ep[w_index & USB_ENDPOINT_NUMBER_MASK];
		pid = control_reg_get_pid(r8a66597, ep->pipenum);
		if (pid == PID_STALL)
			status = 1 << USB_ENDPOINT_HALT;
		else
			status = 0;
		break;
	default:
		pipe_stall(r8a66597, 0);
		return;		/* exit */
	}

	r8a66597->ep0_data = cpu_to_le16(status);
	r8a66597->ep0_req->buf = &r8a66597->ep0_data;
	r8a66597->ep0_req->length = 2;
	/* AV: what happens if we get called again before that gets through? */
	spin_unlock(&r8a66597->lock);
	r8a66597_queue(r8a66597->gadget.ep0, r8a66597->ep0_req, GFP_KERNEL);
	spin_lock(&r8a66597->lock);
}

static void clear_feature(struct r8a66597 *r8a66597,
				struct usb_ctrlrequest *ctrl)
{
	switch (ctrl->bRequestType & USB_RECIP_MASK) {
	case USB_RECIP_DEVICE:
		control_end(r8a66597, 1);
		break;
	case USB_RECIP_INTERFACE:
		control_end(r8a66597, 1);
		break;
	case USB_RECIP_ENDPOINT: {
		struct r8a66597_ep *ep;
		struct r8a66597_request *req;
		u16 w_index = le16_to_cpu(ctrl->wIndex);

		ep = r8a66597->epaddr2ep[w_index & USB_ENDPOINT_NUMBER_MASK];
		if (!ep->wedge) {
			pipe_stop(r8a66597, ep->pipenum);
			control_reg_sqclr(r8a66597, ep->pipenum);
			spin_unlock(&r8a66597->lock);
			usb_ep_clear_halt(&ep->ep);
			spin_lock(&r8a66597->lock);
		}

		control_end(r8a66597, 1);

		req = get_request_from_ep(ep);
		if (ep->busy) {
			ep->busy = 0;
			if (list_empty(&ep->queue))
				break;
			start_packet(ep, req);
		} else if (!list_empty(&ep->queue))
			pipe_start(r8a66597, ep->pipenum);
		}
		break;
	default:
		pipe_stall(r8a66597, 0);
		break;
	}
}

static void set_feature(struct r8a66597 *r8a66597, struct usb_ctrlrequest *ctrl)
{

	switch (ctrl->bRequestType & USB_RECIP_MASK) {
	case USB_RECIP_DEVICE:
		control_end(r8a66597, 1);
		break;
	case USB_RECIP_INTERFACE:
		control_end(r8a66597, 1);
		break;
	case USB_RECIP_ENDPOINT: {
		struct r8a66597_ep *ep;
		u16 w_index = le16_to_cpu(ctrl->wIndex);

		ep = r8a66597->epaddr2ep[w_index & USB_ENDPOINT_NUMBER_MASK];
		pipe_stall(r8a66597, ep->pipenum);

		control_end(r8a66597, 1);
		}
		break;
	default:
		pipe_stall(r8a66597, 0);
		break;
	}
}

/* if return value is true, call class driver's setup() */
static int setup_packet(struct r8a66597 *r8a66597, struct usb_ctrlrequest *ctrl)
{
	u16 *p = (u16 *)ctrl;
	unsigned long offset = USBREQ;
	int i, ret = 0;

	/* read fifo */
	r8a66597_write(r8a66597, ~VALID, INTSTS0);

	for (i = 0; i < 4; i++)
		p[i] = r8a66597_read(r8a66597, offset + i*2);

	/* check request */
	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
		switch (ctrl->bRequest) {
		case USB_REQ_GET_STATUS:
			get_status(r8a66597, ctrl);
			break;
		case USB_REQ_CLEAR_FEATURE:
			clear_feature(r8a66597, ctrl);
			break;
		case USB_REQ_SET_FEATURE:
			set_feature(r8a66597, ctrl);
			break;
		default:
			ret = 1;
			break;
		}
	} else
		ret = 1;
	return ret;
}

static void r8a66597_update_usb_speed(struct r8a66597 *r8a66597)
{
	u16 speed = get_usb_speed(r8a66597);

	switch (speed) {
	case HSMODE:
		r8a66597->gadget.speed = USB_SPEED_HIGH;
		break;
	case FSMODE:
		r8a66597->gadget.speed = USB_SPEED_FULL;
		break;
	default:
		r8a66597->gadget.speed = USB_SPEED_UNKNOWN;
		printk(KERN_ERR "USB speed unknown\n");
	}
}

static void irq_device_state(struct r8a66597 *r8a66597)
{
	u16 dvsq;

	dvsq = r8a66597_read(r8a66597, INTSTS0) & DVSQ;
	r8a66597_write(r8a66597, ~DVST, INTSTS0);

	if (dvsq == DS_DFLT) {
		/* bus reset */
		spin_unlock(&r8a66597->lock);
		r8a66597->driver->disconnect(&r8a66597->gadget);
		spin_lock(&r8a66597->lock);
		r8a66597_update_usb_speed(r8a66597);
	}
	if (r8a66597->old_dvsq == DS_CNFG && dvsq != DS_CNFG)
		r8a66597_update_usb_speed(r8a66597);
	if ((dvsq == DS_CNFG || dvsq == DS_ADDS)
			&& r8a66597->gadget.speed == USB_SPEED_UNKNOWN)
		r8a66597_update_usb_speed(r8a66597);

	r8a66597->old_dvsq = dvsq;
}

static void irq_control_stage(struct r8a66597 *r8a66597)
__releases(r8a66597->lock)
__acquires(r8a66597->lock)
{
	struct usb_ctrlrequest ctrl;
	u16 ctsq;

	ctsq = r8a66597_read(r8a66597, INTSTS0) & CTSQ;
	r8a66597_write(r8a66597, ~CTRT, INTSTS0);

	switch (ctsq) {
	case CS_IDST: {
		struct r8a66597_ep *ep;
		struct r8a66597_request *req;
		ep = &r8a66597->ep[0];
		req = get_request_from_ep(ep);
		transfer_complete(ep, req, 0);
		}
		break;

	case CS_RDDS:
	case CS_WRDS:
	case CS_WRND:
		if (setup_packet(r8a66597, &ctrl)) {
			spin_unlock(&r8a66597->lock);
			if (r8a66597->driver->setup(&r8a66597->gadget, &ctrl)
				< 0)
				pipe_stall(r8a66597, 0);
			spin_lock(&r8a66597->lock);
		}
		break;
	case CS_RDSS:
	case CS_WRSS:
		control_end(r8a66597, 0);
		break;
	default:
		printk(KERN_ERR "ctrl_stage: unexpect ctsq(%x)\n", ctsq);
		break;
	}
}

static irqreturn_t r8a66597_irq(int irq, void *_r8a66597)
{
	struct r8a66597 *r8a66597 = _r8a66597;
	u16 intsts0;
	u16 intenb0;
	u16 brdysts, nrdysts, bempsts;
	u16 brdyenb, nrdyenb, bempenb;
	u16 savepipe;
	u16 mask0;

	spin_lock(&r8a66597->lock);

	intsts0 = r8a66597_read(r8a66597, INTSTS0);
	intenb0 = r8a66597_read(r8a66597, INTENB0);

	savepipe = r8a66597_read(r8a66597, CFIFOSEL);

	mask0 = intsts0 & intenb0;
	if (mask0) {
		brdysts = r8a66597_read(r8a66597, BRDYSTS);
		nrdysts = r8a66597_read(r8a66597, NRDYSTS);
		bempsts = r8a66597_read(r8a66597, BEMPSTS);
		brdyenb = r8a66597_read(r8a66597, BRDYENB);
		nrdyenb = r8a66597_read(r8a66597, NRDYENB);
		bempenb = r8a66597_read(r8a66597, BEMPENB);

		if (mask0 & VBINT) {
			r8a66597_write(r8a66597,  0xffff & ~VBINT,
					INTSTS0);
			r8a66597_start_xclock(r8a66597);

			/* start vbus sampling */
			r8a66597->old_vbus = r8a66597_read(r8a66597, INTSTS0)
					& VBSTS;
			r8a66597->scount = R8A66597_MAX_SAMPLING;

			mod_timer(&r8a66597->timer,
					jiffies + msecs_to_jiffies(50));
		}
		if (intsts0 & DVSQ)
			irq_device_state(r8a66597);

		if ((intsts0 & BRDY) && (intenb0 & BRDYE)
				&& (brdysts & brdyenb))
			irq_pipe_ready(r8a66597, brdysts, brdyenb);
		if ((intsts0 & BEMP) && (intenb0 & BEMPE)
				&& (bempsts & bempenb))
			irq_pipe_empty(r8a66597, bempsts, bempenb);

		if (intsts0 & CTRT)
			irq_control_stage(r8a66597);
	}

	r8a66597_write(r8a66597, savepipe, CFIFOSEL);

	spin_unlock(&r8a66597->lock);
	return IRQ_HANDLED;
}

static void r8a66597_timer(unsigned long _r8a66597)
{
	struct r8a66597 *r8a66597 = (struct r8a66597 *)_r8a66597;
	unsigned long flags;
	u16 tmp;

	spin_lock_irqsave(&r8a66597->lock, flags);
	tmp = r8a66597_read(r8a66597, SYSCFG0);
	if (r8a66597->scount > 0) {
		tmp = r8a66597_read(r8a66597, INTSTS0) & VBSTS;
		if (tmp == r8a66597->old_vbus) {
			r8a66597->scount--;
			if (r8a66597->scount == 0) {
				if (tmp == VBSTS)
					r8a66597_usb_connect(r8a66597);
				else
					r8a66597_usb_disconnect(r8a66597);
			} else {
				mod_timer(&r8a66597->timer,
					jiffies + msecs_to_jiffies(50));
			}
		} else {
			r8a66597->scount = R8A66597_MAX_SAMPLING;
			r8a66597->old_vbus = tmp;
			mod_timer(&r8a66597->timer,
					jiffies + msecs_to_jiffies(50));
		}
	}
	spin_unlock_irqrestore(&r8a66597->lock, flags);
}

/*-------------------------------------------------------------------------*/
static int r8a66597_enable(struct usb_ep *_ep,
			 const struct usb_endpoint_descriptor *desc)
{
	struct r8a66597_ep *ep;

	ep = container_of(_ep, struct r8a66597_ep, ep);
	return alloc_pipe_config(ep, desc);
}

static int r8a66597_disable(struct usb_ep *_ep)
{
	struct r8a66597_ep *ep;
	struct r8a66597_request *req;
	unsigned long flags;

	ep = container_of(_ep, struct r8a66597_ep, ep);
	BUG_ON(!ep);

	while (!list_empty(&ep->queue)) {
		req = get_request_from_ep(ep);
		spin_lock_irqsave(&ep->r8a66597->lock, flags);
		transfer_complete(ep, req, -ECONNRESET);
		spin_unlock_irqrestore(&ep->r8a66597->lock, flags);
	}

	pipe_irq_disable(ep->r8a66597, ep->pipenum);
	return free_pipe_config(ep);
}

static struct usb_request *r8a66597_alloc_request(struct usb_ep *_ep,
						gfp_t gfp_flags)
{
	struct r8a66597_request *req;

	req = kzalloc(sizeof(struct r8a66597_request), gfp_flags);
	if (!req)
		return NULL;

	INIT_LIST_HEAD(&req->queue);

	return &req->req;
}

static void r8a66597_free_request(struct usb_ep *_ep, struct usb_request *_req)
{
	struct r8a66597_request *req;

	req = container_of(_req, struct r8a66597_request, req);
	kfree(req);
}

static int r8a66597_queue(struct usb_ep *_ep, struct usb_request *_req,
			gfp_t gfp_flags)
{
	struct r8a66597_ep *ep;
	struct r8a66597_request *req;
	unsigned long flags;
	int request = 0;

	ep = container_of(_ep, struct r8a66597_ep, ep);
	req = container_of(_req, struct r8a66597_request, req);

	if (ep->r8a66597->gadget.speed == USB_SPEED_UNKNOWN)
		return -ESHUTDOWN;

	spin_lock_irqsave(&ep->r8a66597->lock, flags);

	if (list_empty(&ep->queue))
		request = 1;

	list_add_tail(&req->queue, &ep->queue);
	req->req.actual = 0;
	req->req.status = -EINPROGRESS;

	if (ep->desc == NULL)	/* control */
		start_ep0(ep, req);
	else {
		if (request && !ep->busy)
			start_packet(ep, req);
	}

	spin_unlock_irqrestore(&ep->r8a66597->lock, flags);

	return 0;
}

static int r8a66597_dequeue(struct usb_ep *_ep, struct usb_request *_req)
{
	struct r8a66597_ep *ep;
	struct r8a66597_request *req;
	unsigned long flags;

	ep = container_of(_ep, struct r8a66597_ep, ep);
	req = container_of(_req, struct r8a66597_request, req);

	spin_lock_irqsave(&ep->r8a66597->lock, flags);
	if (!list_empty(&ep->queue))
		transfer_complete(ep, req, -ECONNRESET);
	spin_unlock_irqrestore(&ep->r8a66597->lock, flags);

	return 0;
}

static int r8a66597_set_halt(struct usb_ep *_ep, int value)
{
	struct r8a66597_ep *ep;
	struct r8a66597_request *req;
	unsigned long flags;
	int ret = 0;

	ep = container_of(_ep, struct r8a66597_ep, ep);
	req = get_request_from_ep(ep);

	spin_lock_irqsave(&ep->r8a66597->lock, flags);
	if (!list_empty(&ep->queue)) {
		ret = -EAGAIN;
		goto out;
	}
	if (value) {
		ep->busy = 1;
		pipe_stall(ep->r8a66597, ep->pipenum);
	} else {
		ep->busy = 0;
		ep->wedge = 0;
		pipe_stop(ep->r8a66597, ep->pipenum);
	}

out:
	spin_unlock_irqrestore(&ep->r8a66597->lock, flags);
	return ret;
}

static int r8a66597_set_wedge(struct usb_ep *_ep)
{
	struct r8a66597_ep *ep;
	unsigned long flags;

	ep = container_of(_ep, struct r8a66597_ep, ep);

	if (!ep || !ep->desc)
		return -EINVAL;

	spin_lock_irqsave(&ep->r8a66597->lock, flags);
	ep->wedge = 1;
	spin_unlock_irqrestore(&ep->r8a66597->lock, flags);

	return usb_ep_set_halt(_ep);
}

static void r8a66597_fifo_flush(struct usb_ep *_ep)
{
	struct r8a66597_ep *ep;
	unsigned long flags;

	ep = container_of(_ep, struct r8a66597_ep, ep);
	spin_lock_irqsave(&ep->r8a66597->lock, flags);
	if (list_empty(&ep->queue) && !ep->busy) {
		pipe_stop(ep->r8a66597, ep->pipenum);
		r8a66597_bclr(ep->r8a66597, BCLR, ep->fifoctr);
	}
	spin_unlock_irqrestore(&ep->r8a66597->lock, flags);
}

static struct usb_ep_ops r8a66597_ep_ops = {
	.enable		= r8a66597_enable,
	.disable	= r8a66597_disable,

	.alloc_request	= r8a66597_alloc_request,
	.free_request	= r8a66597_free_request,

	.queue		= r8a66597_queue,
	.dequeue	= r8a66597_dequeue,

	.set_halt	= r8a66597_set_halt,
	.set_wedge	= r8a66597_set_wedge,
	.fifo_flush	= r8a66597_fifo_flush,
};

/*-------------------------------------------------------------------------*/
static struct r8a66597 *the_controller;

int usb_gadget_probe_driver(struct usb_gadget_driver *driver,
		int (*bind)(struct usb_gadget *))
{
	struct r8a66597 *r8a66597 = the_controller;
	int retval;

	if (!driver
			|| driver->speed != USB_SPEED_HIGH
			|| !bind
			|| !driver->setup)
		return -EINVAL;
	if (!r8a66597)
		return -ENODEV;
	if (r8a66597->driver)
		return -EBUSY;

	/* hook up the driver */
	driver->driver.bus = NULL;
	r8a66597->driver = driver;
	r8a66597->gadget.dev.driver = &driver->driver;

	retval = device_add(&r8a66597->gadget.dev);
	if (retval) {
		printk(KERN_ERR "device_add error (%d)\n", retval);
		goto error;
	}

	retval = bind(&r8a66597->gadget);
	if (retval) {
		printk(KERN_ERR "bind to driver error (%d)\n", retval);
		device_del(&r8a66597->gadget.dev);
		goto error;
	}

	r8a66597_bset(r8a66597, VBSE, INTENB0);
	if (r8a66597_read(r8a66597, INTSTS0) & VBSTS) {
		r8a66597_start_xclock(r8a66597);
		/* start vbus sampling */
		r8a66597->old_vbus = r8a66597_read(r8a66597,
					 INTSTS0) & VBSTS;
		r8a66597->scount = R8A66597_MAX_SAMPLING;
		mod_timer(&r8a66597->timer, jiffies + msecs_to_jiffies(50));
	}

	return 0;

error:
	r8a66597->driver = NULL;
	r8a66597->gadget.dev.driver = NULL;

	return retval;
}
EXPORT_SYMBOL(usb_gadget_probe_driver);

int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
{
	struct r8a66597 *r8a66597 = the_controller;
	unsigned long flags;

	if (driver != r8a66597->driver || !driver->unbind)
		return -EINVAL;

	spin_lock_irqsave(&r8a66597->lock, flags);
	if (r8a66597->gadget.speed != USB_SPEED_UNKNOWN)
		r8a66597_usb_disconnect(r8a66597);
	spin_unlock_irqrestore(&r8a66597->lock, flags);

	r8a66597_bclr(r8a66597, VBSE, INTENB0);

	driver->unbind(&r8a66597->gadget);

	init_controller(r8a66597);
	disable_controller(r8a66597);

	device_del(&r8a66597->gadget.dev);
	r8a66597->driver = NULL;
	return 0;
}
EXPORT_SYMBOL(usb_gadget_unregister_driver);

/*-------------------------------------------------------------------------*/
static int r8a66597_get_frame(struct usb_gadget *_gadget)
{
	struct r8a66597 *r8a66597 = gadget_to_r8a66597(_gadget);
	return r8a66597_read(r8a66597, FRMNUM) & 0x03FF;
}

static struct usb_gadget_ops r8a66597_gadget_ops = {
	.get_frame		= r8a66597_get_frame,
};

static int __exit r8a66597_remove(struct platform_device *pdev)
{
	struct r8a66597		*r8a66597 = dev_get_drvdata(&pdev->dev);

	del_timer_sync(&r8a66597->timer);
	iounmap(r8a66597->reg);
	free_irq(platform_get_irq(pdev, 0), r8a66597);
	r8a66597_free_request(&r8a66597->ep[0].ep, r8a66597->ep0_req);
#ifdef CONFIG_HAVE_CLK
	if (r8a66597->pdata->on_chip) {
		clk_disable(r8a66597->clk);
		clk_put(r8a66597->clk);
	}
#endif
	kfree(r8a66597);
	return 0;
}

static void nop_completion(struct usb_ep *ep, struct usb_request *r)
{
}

static int __init r8a66597_probe(struct platform_device *pdev)
{
#ifdef CONFIG_HAVE_CLK
	char clk_name[8];
#endif
	struct resource *res, *ires;
	int irq;
	void __iomem *reg = NULL;
	struct r8a66597 *r8a66597 = NULL;
	int ret = 0;
	int i;
	unsigned long irq_trigger;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		ret = -ENODEV;
		printk(KERN_ERR "platform_get_resource error.\n");
		goto clean_up;
	}

	ires = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	irq = ires->start;
	irq_trigger = ires->flags & IRQF_TRIGGER_MASK;

	if (irq < 0) {
		ret = -ENODEV;
		printk(KERN_ERR "platform_get_irq error.\n");
		goto clean_up;
	}

	reg = ioremap(res->start, resource_size(res));
	if (reg == NULL) {
		ret = -ENOMEM;
		printk(KERN_ERR "ioremap error.\n");
		goto clean_up;
	}

	/* initialize ucd */
	r8a66597 = kzalloc(sizeof(struct r8a66597), GFP_KERNEL);
	if (r8a66597 == NULL) {
		ret = -ENOMEM;
		printk(KERN_ERR "kzalloc error\n");
		goto clean_up;
	}

	spin_lock_init(&r8a66597->lock);
	dev_set_drvdata(&pdev->dev, r8a66597);
	r8a66597->pdata = pdev->dev.platform_data;
	r8a66597->irq_sense_low = irq_trigger == IRQF_TRIGGER_LOW;

	r8a66597->gadget.ops = &r8a66597_gadget_ops;
	device_initialize(&r8a66597->gadget.dev);
	dev_set_name(&r8a66597->gadget.dev, "gadget");
	r8a66597->gadget.is_dualspeed = 1;
	r8a66597->gadget.dev.parent = &pdev->dev;
	r8a66597->gadget.dev.dma_mask = pdev->dev.dma_mask;
	r8a66597->gadget.dev.release = pdev->dev.release;
	r8a66597->gadget.name = udc_name;

	init_timer(&r8a66597->timer);
	r8a66597->timer.function = r8a66597_timer;
	r8a66597->timer.data = (unsigned long)r8a66597;
	r8a66597->reg = reg;

#ifdef CONFIG_HAVE_CLK
	if (r8a66597->pdata->on_chip) {
		snprintf(clk_name, sizeof(clk_name), "usb%d", pdev->id);
		r8a66597->clk = clk_get(&pdev->dev, clk_name);
		if (IS_ERR(r8a66597->clk)) {
			dev_err(&pdev->dev, "cannot get clock \"%s\"\n",
				clk_name);
			ret = PTR_ERR(r8a66597->clk);
			goto clean_up;
		}
		clk_enable(r8a66597->clk);
	}
#endif

	disable_controller(r8a66597); /* make sure controller is disabled */

	ret = request_irq(irq, r8a66597_irq, IRQF_DISABLED | IRQF_SHARED,
			udc_name, r8a66597);
	if (ret < 0) {
		printk(KERN_ERR "request_irq error (%d)\n", ret);
		goto clean_up2;
	}

	INIT_LIST_HEAD(&r8a66597->gadget.ep_list);
	r8a66597->gadget.ep0 = &r8a66597->ep[0].ep;
	INIT_LIST_HEAD(&r8a66597->gadget.ep0->ep_list);
	for (i = 0; i < R8A66597_MAX_NUM_PIPE; i++) {
		struct r8a66597_ep *ep = &r8a66597->ep[i];

		if (i != 0) {
			INIT_LIST_HEAD(&r8a66597->ep[i].ep.ep_list);
			list_add_tail(&r8a66597->ep[i].ep.ep_list,
					&r8a66597->gadget.ep_list);
		}
		ep->r8a66597 = r8a66597;
		INIT_LIST_HEAD(&ep->queue);
		ep->ep.name = r8a66597_ep_name[i];
		ep->ep.ops = &r8a66597_ep_ops;
		ep->ep.maxpacket = 512;
	}
	r8a66597->ep[0].ep.maxpacket = 64;
	r8a66597->ep[0].pipenum = 0;
	r8a66597->ep[0].fifoaddr = CFIFO;
	r8a66597->ep[0].fifosel = CFIFOSEL;
	r8a66597->ep[0].fifoctr = CFIFOCTR;
	r8a66597->ep[0].fifotrn = 0;
	r8a66597->ep[0].pipectr = get_pipectr_addr(0);
	r8a66597->pipenum2ep[0] = &r8a66597->ep[0];
	r8a66597->epaddr2ep[0] = &r8a66597->ep[0];

	the_controller = r8a66597;

	r8a66597->ep0_req = r8a66597_alloc_request(&r8a66597->ep[0].ep,
							GFP_KERNEL);
	if (r8a66597->ep0_req == NULL)
		goto clean_up3;
	r8a66597->ep0_req->complete = nop_completion;

	init_controller(r8a66597);

	dev_info(&pdev->dev, "version %s\n", DRIVER_VERSION);
	return 0;

clean_up3:
	free_irq(irq, r8a66597);
clean_up2:
#ifdef CONFIG_HAVE_CLK
	if (r8a66597->pdata->on_chip) {
		clk_disable(r8a66597->clk);
		clk_put(r8a66597->clk);
	}
#endif
clean_up:
	if (r8a66597) {
		if (r8a66597->ep0_req)
			r8a66597_free_request(&r8a66597->ep[0].ep,
						r8a66597->ep0_req);
		kfree(r8a66597);
	}
	if (reg)
		iounmap(reg);

	return ret;
}

/*-------------------------------------------------------------------------*/
static struct platform_driver r8a66597_driver = {
	.remove =	__exit_p(r8a66597_remove),
	.driver		= {
		.name =	(char *) udc_name,
	},
};

static int __init r8a66597_udc_init(void)
{
	return platform_driver_probe(&r8a66597_driver, r8a66597_probe);
}
module_init(r8a66597_udc_init);

static void __exit r8a66597_udc_cleanup(void)
{
	platform_driver_unregister(&r8a66597_driver);
}
module_exit(r8a66597_udc_cleanup);

MODULE_DESCRIPTION("R8A66597 USB gadget driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Yoshihiro Shimoda");