Aquaris-M10-4G/drivers/misc/mediatek/ssusb/mu3d/musb_gadget.c

/*
 * MUSB OTG driver peripheral support
 *
 * Copyright 2005 Mentor Graphics Corporation
 * Copyright (C) 2005-2006 by Texas Instruments
 * Copyright (C) 2006-2007 Nokia Corporation
 * Copyright (C) 2009 MontaVista Software, Inc. <source@mvista.com>
 *
 * 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.
 *
 * 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.
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/timer.h>
#include <linux/module.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>

#include "musb_core.h"
/* #include "mu3d_hal_osal.h" */
#include "mu3d_hal_qmu_drv.h"
#include "mu3d_hal_usb_drv.h"
#include "mu3d_hal_hw.h"
#include "ssusb_io.h"

/* ----------------------------------------------------------------------- */

#define is_buffer_mapped(req) (req->map_state != UN_MAPPED)

/* Maps the buffer to dma  */

static inline void map_dma_buffer(struct musb_request *request,
				  struct musb *musb, struct musb_ep *musb_ep)
{

	request->map_state = UN_MAPPED;

#ifndef USE_SSUSB_QMU
	/* for pio need modify it  yun */
	return;
#endif
	if (request->request.dma == DMA_ADDR_INVALID) {
		request->request.dma = dma_map_single(musb->controller,
						      request->request.buf,
						      request->request.length,
						      request->tx ? DMA_TO_DEVICE :
						      DMA_FROM_DEVICE);
		request->map_state = MUSB_MAPPED;
		mu3d_dbg(K_DEBUG, "%s - dma_map_single\n", __func__);
	} else {
		dma_sync_single_for_device(musb->controller,
					   request->request.dma,
					   request->request.length,
					   request->tx ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
		request->map_state = PRE_MAPPED;
		mu3d_dbg(K_DEBUG, "%s - dma_sync_single_for_device\n", __func__);
	}
}

/* Unmap the buffer from dma and maps it back to cpu */
static inline void unmap_dma_buffer(struct musb_request *request, struct musb *musb)
{
	if (!is_buffer_mapped(request))
		return;

	if (request->request.dma == DMA_ADDR_INVALID) {
		dev_vdbg(musb->controller, "not unmapping a never mapped buffer\n");
		return;
	}
	if (request->map_state == MUSB_MAPPED) {
		/* avoid adb push error ,modify later */
		dma_unmap_single(musb->controller, request->request.dma,
				 request->request.length,
				 request->tx ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
		request->request.dma = DMA_ADDR_INVALID;
		mu3d_dbg(K_DEBUG, "%s - dma_unmap_single\n", __func__);
	} else {		/* PRE_MAPPED */
		dma_sync_single_for_cpu(musb->controller,
					request->request.dma,
					request->request.length,
					request->tx ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
		mu3d_dbg(K_DEBUG, "%s - dma_sync_single_for_cpu\n", __func__);
	}
	request->map_state = UN_MAPPED;
}

/*
 * Immediately complete a request.
 *
 * @param request the request to complete
 * @param status the status to complete the request with
 * Context: controller locked, IRQs blocked.
 */
void musb_g_giveback(struct musb_ep *ep,
		     struct usb_request *request,
		     int status) __releases(ep->musb->lock) __acquires(ep->musb->lock)
{
	struct musb_request *req;
	struct musb *musb;
	int busy = ep->busy;

	req = to_musb_request(request);

	list_del(&req->list);
	if (req->request.status == -EINPROGRESS)
		req->request.status = status;
	musb = req->musb;
	/* mu3d_dbg(K_DEBUG, "%s - 0\n", __func__); */
	/* if ((request->status == 0) && (512 < request->actual) && (request->actual < 1024)) */
	/* print_buf((char *)request->buf, request->actual); */

	ep->busy = 1;
	spin_unlock(&musb->lock);
	unmap_dma_buffer(req, musb);
	/* mu3d_dbg(K_DEBUG, "%s - 1\n", __func__); */
	/* if ((request->status == 0) && (512 < request->actual) && (request->actual < 1024)) */
	/* print_buf((char *)request->buf, request->actual); */
	if (request->status == 0)
		/* dev_dbg(musb->controller, "%s done request %p,  %d/%d\n", */
		mu3d_dbg(K_DEBUG, "%s done request %p,  %d/%d\n",
			 ep->end_point.name, request, req->request.actual, req->request.length);
	else
		/* dev_dbg(musb->controller, "%s request %p, %d/%d fault %d\n", */
		mu3d_dbg(K_DEBUG, "%s request %p, %d/%d fault %d\n",
			 ep->end_point.name, request,
			 req->request.actual, req->request.length, request->status);

	mu3d_dbg(K_DEBUG, "musb_g_giveback : %p, #%d\n", request, req->request.actual);
	req->request.complete(&req->ep->end_point, &req->request);
	spin_lock(&musb->lock);
	ep->busy = busy;
}

/* ----------------------------------------------------------------------- */

/*
 * Abort requests queued to an endpoint using the status. Synchronous.
 * caller locked controller and blocked irqs, and selected this ep.
 */
static void nuke(struct musb_ep *ep, const int status)
{
	struct musb_request *req = NULL;

	mu3d_dbg(K_INFO, "%s status=%d %s-%s\n", __func__, status, ep->end_point.name,
		 (ep->is_in ? "IN" : "OUT"));

	ep->busy = 1;

#ifdef USE_SSUSB_QMU
	mu3d_hal_flush_qmu(ep->musb, ep->hw_ep->epnum, (ep->is_in ? USB_TX : USB_RX));
	/* mu3d_hal_start_qmu(ep->musb, ep->musb->mregs, ep->hw_ep->epnum, (ep->is_in? USB_TX: USB_RX)); */
#endif

	while (!list_empty(&ep->req_list)) {
		req = list_first_entry(&ep->req_list, struct musb_request, list);
		musb_g_giveback(ep, &req->request, status);
		mu3d_dbg(K_INFO, "%s call musb_g_giveback() EP is %s\n", __func__,
			 ep->end_point.name);
	}
}

/* ----------------------------------------------------------------------- */

/* Data transfers - pure PIO, pure DMA, or mixed mode */

/*
 * This assumes the separate CPPI engine is responding to DMA requests
 * from the usb core ... sequenced a bit differently from mentor dma.
 */

static inline int max_ep_writesize(struct musb *musb, struct musb_ep *ep)
{
	/* if (can_bulk_split(musb, ep->type)) */
	/* return ep->hw_ep->max_packet_sz_tx; */
	/* else */
	return ep->packet_sz;
}


/* #ifdef CONFIG_USB_INVENTRA_DMA */

/* Peripheral tx (IN) using Mentor DMA works as follows:
	Only mode 0 is used for transfers <= wPktSize,
	mode 1 is used for larger transfers,

	One of the following happens:
	- Host sends IN token which causes an endpoint interrupt
		-> TxAvail
			-> if DMA is currently busy, exit.
			-> if queue is non-empty, txstate().

	- Request is queued by the gadget driver.
		-> if queue was previously empty, txstate()

	txstate()
		-> start
		  /\	-> setup DMA
		  |     (data is transferred to the FIFO, then sent out when
		  |	IN token(s) are recd from Host.
		  |		-> DMA interrupt on completion
		  |		   calls TxAvail.
		  |		      -> stop DMA, ~DMAENAB,
		  |		      -> set TxPktRdy for last short pkt or zlp
		  |		      -> Complete Request
		  |		      -> Continue next request (call txstate)
		  |___________________________________|

 * Non-Mentor DMA engines can of course work differently, such as by
 * upleveling from irq-per-packet to irq-per-buffer.
 */

/* #endif */

/* #ifndef USE_SSUSB_QMU */
/* maybe noneed it such macro modify later yun */
/*
 * An endpoint is transmitting data. This can be called either from
 * the IRQ routine or from ep.queue() to kickstart a request on an
 * endpoint.
 *
 * Context: controller locked, IRQs blocked, endpoint selected
 */
static void txstate(struct musb *musb, struct musb_request *req)
{
	/* u8 epnum = req->epnum; */
	struct musb_ep *musb_ep = req->ep;
	struct usb_request *request;
	struct musb_hw_ep *hw_ep = musb_ep->hw_ep;
	u16 count = 0;
	u32 txcsr0 = 0;
	u32 maxp;
	/* int use_dma = 0; */

	mu3d_dbg(K_DEBUG, "%s\n", __func__);

	/* we shouldn't get here while DMA is active ... but we do ... */
	/* if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) { */
	/* dev_dbg(musb->controller, "dma pending...\n"); */
	/* return; */
	/* } */

	/* read TXCSR before */
	txcsr0 = mu3d_readl(hw_ep->addr_txcsr0, 0);
	request = &req->request;
	count = min(max_ep_writesize(musb, musb_ep), (int)(request->length - request->actual));

	if (txcsr0 & TX_TXPKTRDY)
		return;

	if (txcsr0 & TX_SENDSTALL)
		return;

	/* if (!use_dma) { */
	/*
	 * Unmap the dma buffer back to cpu if dma channel
	 * programming fails
	 */
	/* unmap_dma_buffer(req, musb);  //modify it and fifo write bellow later yun */

	maxp = musb_ep->end_point.maxpacket;
	/* mu3d_hal_write_fifo(musb_ep->hw_ep, epnum, fifo_count, (u8 *) (request->buf + request->actual), maxp); */
	musb_write_fifo(musb_ep->hw_ep, count, (u8 *) (request->buf + request->actual));
	request->actual += count;

	/* if (count == 0) { */
	/* mu3d_setmsk(hw_ep->addr_txcsr0, 0, TX_TXPKTRDY); */
	/* } else { */
#ifdef AUTOSET
	if (count < maxp) {
		mu3d_setmsk(hw_ep->addr_txcsr0, 0, TX_TXPKTRDY);
		mu3d_dbg(K_DEBUG, "short packet\n");
	}
#else
	mu3d_setmsk(hw_ep->addr_txcsr0, 0, TX_TXPKTRDY);
#endif
	/* } */

	mu3d_dbg(K_DEBUG, "%s actual=%d, count=%d\n", __func__, request->actual, count);

#if 0
	musb_write_fifo(musb_ep->hw_ep, fifo_count, (u8 *) (request->buf + request->actual));
	request->actual += fifo_count;
	txcsr0 &= TX_W1C_BITS;
	txcsr0 |= TX_TXPKTRDY;
	os_writel(musb->endpoints[epnum].addr_txcsr0, txcsr0);
#endif
	/* } */
}

/* #endif */
/*
 * FIFO state update (e.g. data ready).
 * Called from IRQ,  with controller locked.
 */
void musb_g_tx(struct musb *musb, u8 epnum)
{
	u32 txcsr0;
	struct musb_request *req;
	struct usb_request *request;
	struct musb_ep *musb_ep = &musb->endpoints[epnum].ep_in;
	/* struct dma_channel *dma; */

	req = next_request(musb_ep);
	if (NULL == req)
		return;

	request = &req->request;

	txcsr0 = mu3d_readl(musb_ep->hw_ep->addr_txcsr0, 0);

	/* dma = is_dma_capable() ? musb_ep->dma : NULL; */
	/* if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) { */
	/*
	 * SHOULD NOT HAPPEN... has with CPPI though, after
	 * changing SENDSTALL (and other cases); harmless?
	 */
	/* dev_dbg(musb->controller, "%s dma still busy?\n", musb_ep->end_point.name); */
	/* return; */
	/* } */

	if (request) {
		/*
		 * First, maybe a terminating short packet. Some DMA
		 * engines might handle this by themselves.
		 */
		if ((request->zero && request->length && (request->length % musb_ep->packet_sz == 0)
		     && (request->actual == request->length))
		    ) {
			/*
			 * On DMA completion, FIFO may not be
			 * available yet...
			 */
			if (txcsr0 & TX_TXPKTRDY)
				return;

			dev_dbg(musb->controller, "sending zero pkt\n");
			mu3d_writel(musb_ep->hw_ep->addr_txcsr0, 0,
				    (txcsr0 & TX_W1C_BITS) | TX_TXPKTRDY);
			request->zero = 0;
		}

		if (request->actual == request->length) {
			musb_g_giveback(musb_ep, request, 0);
			req = musb_ep->desc ? next_request(musb_ep) : NULL;
			if (!req) {
				dev_dbg(musb->controller, "%s idle now\n", musb_ep->end_point.name);
				return;
			}
		}
/* #ifdef USE_SSUSB_QMU */
		/* txstate_qmu(musb, req); */
/* #else */
		txstate(musb, req);
/* #endif */
	}
}

/* ------------------------------------------------------------ */

/* #ifdef CONFIG_USB_INVENTRA_DMA */

/* Peripheral rx (OUT) using Mentor DMA works as follows:
	- Only mode 0 is used.

	- Request is queued by the gadget class driver.
		-> if queue was previously empty, rxstate()

	- Host sends OUT token which causes an endpoint interrupt
	  /\      -> RxReady
	  |	      -> if request queued, call rxstate
	  |		/\	-> setup DMA
	  |		|	     -> DMA interrupt on completion
	  |		|		-> RxReady
	  |		|		      -> stop DMA
	  |		|		      -> ack the read
	  |		|		      -> if data recd = max expected
	  |		|				by the request, or host
	  |		|				sent a short packet,
	  |		|				complete the request,
	  |		|				and start the next one.
	  |		|_____________________________________|
	  |					 else just wait for the host
	  |					    to send the next OUT token.
	  |__________________________________________________|

 * Non-Mentor DMA engines can of course work differently.
 */

/* #endif */

/*
 * Context: controller locked, IRQs blocked, endpoint selected
 */
static void rxstate(struct musb *musb, struct musb_request *req)
{
	const u8 epnum = req->epnum;
	struct usb_request *request = &req->request;
	struct musb_ep *musb_ep;
	u16 fifo_count;
	unsigned len = 0;
	struct musb_hw_ep *hw_ep = &musb->endpoints[epnum];
	u32 rxcsr0 = mu3d_readl(hw_ep->addr_rxcsr0, 0);

	musb_ep = &hw_ep->ep_out;

	fifo_count = musb_ep->packet_sz;

	/* We shouldn't get here while DMA is active, but we do... */
	/* if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) { */
	/* dev_dbg(musb->controller, "DMA pending...\n"); */
	/* return; */
	/* } */

	mu3d_dbg(K_DEBUG, "req-list(%p) next=%p, prev=%p\n", &musb_ep->req_list,
		 musb_ep->req_list.next, musb_ep->req_list.prev);

	mu3d_dbg(K_DEBUG, "epnum=%d, rxcsr addr=0x%p, rxcsr0=%#x\n", epnum,
		 musb->endpoints[epnum].addr_rxcsr0, rxcsr0);

	if (rxcsr0 & RX_SENDSTALL)
		return;

	if (rxcsr0 & RX_RXPKTRDY) {
		fifo_count =
		    (mu3d_xcsr_readl(musb->mac_base, U3D_RX1CSR3, epnum) >> EP_RX_COUNT_OFST);
		if (request->actual < request->length) {
			len = request->length - request->actual;
			fifo_count = min_t(unsigned, len, fifo_count);
			/* fifo_count = mu3d_hal_read_fifo( epnum, (request->buf + request->actual)); */
			musb_read_fifo(&musb->endpoints[epnum], fifo_count,
				       (request->buf + request->actual));
			request->actual += fifo_count;

			/* ack the read! */
#ifdef AUTOCLEAR
			if (!fifo_count) {
				mu3d_xcsr_writel(musb->mac_base, U3D_RX1CSR0, epnum,
						 mu3d_xcsr_readl(musb->mac_base, U3D_RX1CSR0,
								 epnum) | RX_RXPKTRDY);
			}
#else
			mu3d_xcsr_writel(musb->mac_base, U3D_RX1CSR0, epnum,
					 mu3d_xcsr_readl(musb->mac_base, U3D_RX1CSR0,
							 epnum) | RX_RXPKTRDY);
#endif
		}
	}

	mu3d_dbg(K_DEBUG, "%s length=%d, actual=%d, fifo_count=%d, packet_sz=%d\n",
		 __func__, request->length, request->actual, fifo_count, musb_ep->packet_sz);

	/* reach the end or short packet detected */
	if (request->actual == request->length || fifo_count < musb_ep->packet_sz)
		musb_g_giveback(musb_ep, request, 0);
}

/*
 * Data ready for a request; called from IRQ
 */
void musb_g_rx(struct musb *musb, u8 epnum)
{
	u32 rxcsr0;
	struct musb_request *req;
	struct usb_request *request;
	struct musb_ep *musb_ep;
	/* struct dma_channel *dma; */
	struct musb_hw_ep *hw_ep = &musb->endpoints[epnum];

	musb_ep = &hw_ep->ep_out;
	mu3d_dbg(K_DEBUG, "%s-%d ep%dRx\n", __func__, __LINE__, epnum);
	mu3d_dbg(K_DEBUG, "req-list(%p) next=%p, prev=%p\n", &musb_ep->req_list,
		 musb_ep->req_list.next, musb_ep->req_list.prev);

	req = next_request(musb_ep);
	if (!req) {
		mu3d_dbg(K_DEBUG, "%s-%d ep%dRx, RXCSR0-0x%x(request is null, return)\n",
			 __func__, __LINE__, epnum, mu3d_readl(hw_ep->addr_rxcsr0, 0));
		return;
	}

	request = &req->request;

	rxcsr0 = mu3d_readl(hw_ep->addr_rxcsr0, 0);

	if (rxcsr0 & RX_SENTSTALL) {
		mu3d_dbg(K_DEBUG, "%s-%d ep%dRx (rx_sentstall)\n", __func__, __LINE__, epnum);

		/* EPN needs to continuous sending STALL until host set clear_feature to clear the status. */

		/* musb_writew(epio, MUSB_RXCSR, csr); */
		mu3d_writel(hw_ep->addr_rxcsr0, 0, (rxcsr0 & RX_W1C_BITS) | RX_SENTSTALL);

		return;
	}

	/* dma = is_dma_capable() ? musb_ep->dma : NULL; */

	/* Analyze request */
	rxstate(musb, req);
}

/* ------------------------------------------------------------ */

static int musb_gadget_enable(struct usb_ep *ep, const struct usb_endpoint_descriptor *desc)
{
	unsigned long flags;
	struct musb_ep *musb_ep;
	struct musb_hw_ep *hw_ep;
	struct musb *musb;
	void __iomem *mbase;
	u8 epnum = 0;
	unsigned maxp = 0;
	int status = -EINVAL;
	TRANSFER_TYPE type = USB_CTRL;
	USB_DIR dir = USB_TX;


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

	mu3d_dbg(K_INFO, "musb_gadget_enable %s\n", ep->name);

	musb_ep = to_musb_ep(ep);
	hw_ep = musb_ep->hw_ep;
	musb = musb_ep->musb;
	mbase = musb->mac_base;
	epnum = hw_ep->epnum;


	spin_lock_irqsave(&musb->lock, flags);

	if (musb_ep->desc) {
		status = -EBUSY;
		goto fail;
	}
	musb_ep->type = usb_endpoint_type(desc);

	/* check direction and (later) maxpacket size against endpoint */
	if (usb_endpoint_num(desc) != epnum)
		goto fail;

	/* REVISIT this rules out high bandwidth periodic transfers */
	maxp = le16_to_cpu(desc->wMaxPacketSize);
	if (maxp & ~0x07ff)
		goto fail;

	musb_ep->packet_sz = maxp;

	mu3d_dbg(K_DEBUG, "U3D_EPIER=0x%X\n", mu3d_readl(mbase, U3D_EPIER));

	/* enable the interrupts for the endpoint, set the endpoint
	 * packet size (or fail), set the mode, clear the fifo
	 */
	if (usb_endpoint_dir_in(desc)) {	/* TX */


#ifndef USE_SSUSB_QMU
		u32 int_txe = mu3d_readl(mbase, U3D_EPIER);
#endif
		if (hw_ep->is_shared_fifo)
			musb_ep->is_in = 1;
		if (!musb_ep->is_in)
			goto fail;

		if (maxp > hw_ep->max_packet_sz_tx)
			goto fail;

#ifndef USE_SSUSB_QMU
		mu3d_dbg(K_DEBUG, "epnum=%d, int_txe=0x%x, EPIER=0x%x+\n", epnum, int_txe,
			 mu3d_readl(mbase, U3D_EPIER));
		int_txe |= (1 << epnum);
		mu3d_writel(mbase, U3D_EPIESR, int_txe);
		mu3d_dbg(K_DEBUG, "epnum=%d, int_txe=0x%x, EPIER=0x%x-\n", epnum, int_txe,
			 mu3d_readl(mbase, U3D_EPIER));
#endif
		dir = USB_TX;

		switch (musb_ep->type) {
		case USB_ENDPOINT_XFER_BULK:
			type = USB_BULK;
			break;
		case USB_ENDPOINT_XFER_ISOC:
			type = USB_ISO;
			break;
		case USB_ENDPOINT_XFER_INT:
			type = USB_INTR;
			break;
		}
	} else {
#ifndef USE_SSUSB_QMU
		u32 int_rxe = mu3d_readl(mbase, U3D_EPIER);
#endif
		if (hw_ep->is_shared_fifo)
			musb_ep->is_in = 0;
		if (musb_ep->is_in)
			goto fail;

		if (maxp > hw_ep->max_packet_sz_rx) {
			dev_dbg(musb->controller, "packet size beyond hardware FIFO size\n");
			goto fail;
		}
#ifndef USE_SSUSB_QMU
		mu3d_dbg(K_DEBUG, "int_rxe=0x%x, EPIER=0x%x+\n", int_rxe,
			 mu3d_readl(mbase, U3D_EPIER));
		int_rxe |= (BIT16 << epnum);
		mu3d_writel(mbase, U3D_EPIESR, int_rxe);
		mu3d_dbg(K_DEBUG, "int_rxe=0x%x, EPIER=0x%x-\n", int_rxe,
			 mu3d_readl(mbase, U3D_EPIER));
#endif
		dir = USB_RX;

		switch (musb_ep->type) {
		case USB_ENDPOINT_XFER_BULK:
			type = USB_BULK;
			break;
		case USB_ENDPOINT_XFER_ISOC:
			type = USB_ISO;
			break;
		case USB_ENDPOINT_XFER_INT:
			type = USB_INTR;
			break;
		}

	}

	/*
	 * At PIO with 2 slot(double buffer), the host transfers 512 + N bytes.
	 * 512 would fill the 1st slot. And the rest of N bytes will put into
	 * the 2nd slot. The interrupt is coming. The driver reads the data
	 * stored at the 1st slot. Then driver expects the next interrupt to
	 * read the data at the 2nd slot. But the interrupt does not show up!
	 * Designer says maybe the interrupt the driver handles is the interrupt
	 * come from the 2nd slot. the system does not fast enough. So the later
	 * one and the previous one merge to one interrupt.
	 * So at FPGA stage and PIO, just use _ONE_ slot.
	 */
#ifdef USE_SSUSB_QMU
	mu3d_hal_ep_enable(musb, epnum, dir, type, maxp, 0, MAX_SLOT, 0, 0);
#else
	/*TODO: Check support mulitslots on real ship */
	mu3d_hal_ep_enable(musb, epnum, dir, type, maxp, 0, 0, 0, 0);
#endif

#ifdef USE_SSUSB_QMU
	mu3d_hal_start_qmu(musb, epnum, dir);
#endif
	/* NOTE:  all the I/O code _should_ work fine without DMA, in case
	 * for some reason you run out of channels here.
	 */
	/* if (is_dma_capable() && musb->dma_controller) { */
	/* struct dma_controller *c = musb->dma_controller; */

	/* musb_ep->dma = c->channel_alloc(c, hw_ep, (desc->bEndpointAddress & USB_DIR_IN)); */
	/* } else */
	/* musb_ep->dma = NULL; */

	musb_ep->desc = desc;
	musb_ep->busy = 0;
	musb_ep->wedged = 0;
	status = 0;

	musb->active_ep++;
	mu3d_dbg(K_DEBUG, "[U3D]%s active_ep=%d\n", __func__, musb->active_ep);

	queue_work(musb->wq, &musb->otg_event_work);

fail:
	spin_unlock_irqrestore(&musb->lock, flags);

	return status;
}

/*
 * Disable an endpoint flushing all requests queued.
 */
static int musb_gadget_disable(struct usb_ep *ep)
{
	struct musb_ep *musb_ep = to_musb_ep(ep);
	struct musb *musb = musb_ep->musb;
	struct musb_hw_ep *hw_ep = musb_ep->hw_ep;
	u8 epnum = musb_ep->current_epnum;
	unsigned long flags;
	u32 rxcsr0_val;
	u32 txcsr0_val;
	int status = 0;

	mu3d_dbg(K_INFO, "%s\n", __func__);

	spin_lock_irqsave(&musb->lock, flags);

#ifndef USE_SSUSB_QMU

	/* disable interrupt */
	if (musb_ep->is_in) {	/* TX */
		mu3d_setmsk(musb->mac_base, U3D_EPIECR, (1 << epnum));
	} else {
		mu3d_setmsk(musb->mac_base, U3D_EPIECR, (BIT16 << epnum));
	}
#endif
	/* zero the endpoint sizes */
	if (musb_ep->is_in) {
		txcsr0_val = mu3d_readl(hw_ep->addr_txcsr0, 0);
		txcsr0_val &= ~(TX_TXMAXPKTSZ);
		txcsr0_val &= TX_W1C_BITS;
		mu3d_writel(hw_ep->addr_txcsr0, 0, txcsr0_val);

		/* os_writelmskumsk(musb->endpoints[epnum].addr_rxcsr0, 0, TX_TXMAXPKTSZ, TX_W1C_BITS); */
	} else {
		rxcsr0_val = mu3d_readl(hw_ep->addr_rxcsr0, 0);
		rxcsr0_val &= ~(RX_RXMAXPKTSZ);
		rxcsr0_val &= RX_W1C_BITS;
		mu3d_writel(hw_ep->addr_rxcsr0, 0, rxcsr0_val);
		/* os_writelmskumsk(musb->endpoints[epnum].addr_rxcsr0, 0, RX_RXMAXPKTSZ, RX_W1C_BITS); */
	}

	musb_ep->desc = NULL;

	/* abort all pending DMA and requests */
	nuke(musb_ep, -ESHUTDOWN);

	mu3d_hal_unfigured_ep_num(musb, epnum, (musb_ep->is_in ? USB_TX : USB_RX));

	queue_work(musb->wq, &musb->otg_event_work);

	musb->active_ep--;
	mu3d_dbg(K_INFO, "[U3D]%s active_ep=%d, mu3d is_active=%d\n", __func__,
		 musb->active_ep, musb->is_active);

	if (musb->active_ep == 0 && musb->is_active == 0 && !is_maual_otg(musb->ssusb))
		queue_work(musb->wq, &musb->suspend_work);

	spin_unlock_irqrestore(&(musb->lock), flags);

	dev_dbg(musb->controller, "%s\n", musb_ep->end_point.name);

	return status;
}

/*
 * Allocate a request for an endpoint.
 * Reused by ep0 code.
 */
struct usb_request *musb_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
{
	struct musb_ep *musb_ep = to_musb_ep(ep);
	struct musb_request *request = NULL;

	request = kzalloc(sizeof(*request), gfp_flags);
	if (!request)
		return NULL;

	request->request.dma = DMA_ADDR_INVALID;
	request->epnum = musb_ep->current_epnum;
	request->ep = musb_ep;

	return &request->request;
}

/*
 * Free a request
 * Reused by ep0 code.
 */
void musb_free_request(struct usb_ep *ep, struct usb_request *req)
{
	kfree(to_musb_request(req));
}

/* static LIST_HEAD(buffers); */

/* struct free_record { */
/* struct list_head list; */
/* struct device *dev; */
/* unsigned bytes; */
/* dma_addr_t dma; */
/* }; */

/*
 * Context: controller locked, IRQs blocked.
 */
void musb_ep_restart(struct musb *musb, struct musb_request *req)
{
	/*
	 * We don't do anything if QMU because QMU is already
	 * waiting there when musb_gadget_queue().
	 */
#ifndef USE_SSUSB_QMU
	/* dev_dbg(musb->controller, "<== %s request %p len %u on hw_ep%d\n", */
	mu3d_dbg(K_DEBUG, " %s %s request %p len %u on hw_ep%d\n",
		 __func__, req->tx ? "TX/IN" : "RX/OUT",
		 &req->request, req->request.length, req->epnum);

	if (req->tx)
		txstate(musb, req);
	else
		rxstate(musb, req);
#endif
}

static int musb_gadget_queue(struct usb_ep *ep, struct usb_request *req, gfp_t gfp_flags)
{
	struct musb_ep *musb_ep;
	struct musb_request *request;
	struct musb *musb;
	int status = 0;
	unsigned long lockflags;

	if (!ep || !req)
		return -EINVAL;
	if (!req->buf)
		return -ENODATA;

	musb_ep = to_musb_ep(ep);
	musb = musb_ep->musb;

	request = to_musb_request(req);
	request->musb = musb;

	if (request->ep != musb_ep)
		return -EINVAL;

	mu3d_dbg(K_DEBUG, "%s %s, req=%p, len#%d\n", __func__, ep->name, req,
		 request->request.length);

	/* dev_dbg(musb->controller, "<== to %s request=%p\n", ep->name, req); */

	/* request is mine now... */
	request->request.actual = 0;
	request->request.status = -EINPROGRESS;
	request->epnum = musb_ep->current_epnum;
	request->tx = musb_ep->is_in;

	map_dma_buffer(request, musb, musb_ep);

	spin_lock_irqsave(&musb->lock, lockflags);

	/* don't queue if the ep is down */
	if (!musb_ep->desc) {
		dev_dbg(musb->controller, "req %p queued to %s while ep %s\n",
			req, ep->name, "disabled");
		status = -ESHUTDOWN;
		goto cleanup;
	}

	/* add request to the list */
	list_add_tail(&request->list, &musb_ep->req_list);

#ifdef USE_SSUSB_QMU
	if (request->request.dma != DMA_ADDR_INVALID) {
		qmu_dbg(K_DEBUG, "%s %s EP%d, len=%d, maxp=%d request=%p\n",
			request->tx ? "[TX]" : "[RX]", __func__, request->epnum,
			request->request.length, ep->maxpacket, request);
		if (request->tx) {
			struct musb_hw_ep *hw_ep = musb_ep->hw_ep;

			request->request.actual = request->request.length;
			if (request->request.length > 0) {

				mu3d_hal_insert_transfer_gpd(request->epnum, USB_TX,
							     request->request.dma,
							     request->request.length, true, true,
							     false,
							     ((request->request.zero == 1) ? 1 : 0),
							     ep->maxpacket);
				/*Enable Tx_DMAREQEN */
				mu3d_setmsk(hw_ep->addr_txcsr0, 0, TX_DMAREQEN);

				mu3d_hal_resume_qmu(musb, request->epnum, USB_TX);

			} else if (request->request.length == 0) {

				qmu_dbg(K_DEBUG, "[TX]" "==Have send ZLP==\n");

				/* If there is only ZLP in the request list. Just send ZLP directly */
				if (next_request(musb_ep) == request) {

					/* Send ZLP by setting TXPKTRDY, TODO add timeout... */
					while (!(mu3d_readl(hw_ep->addr_txcsr0, 0) & TX_FIFOFULL)) {
						mu3d_clrmsk(hw_ep->addr_txcsr0, 0, TX_DMAREQEN);
						/* mb(); */
						mu3d_setmsk(hw_ep->addr_txcsr0, 0, TX_TXPKTRDY);
						break;
					}

					qmu_dbg(K_DEBUG,
						"[TX]Give back ZLP of EP%d. actual:%d, length:%d %p\n",
						request->epnum,
						request->request.actual,
						request->request.length, request);

					musb_g_giveback(musb_ep, &(request->request), 0);

				}
			}
		} else {
			mu3d_hal_insert_transfer_gpd(request->epnum, USB_RX, request->request.dma,
						     request->request.length, true, true, false,
						     0, ep->maxpacket);
			mu3d_hal_resume_qmu(musb, request->epnum, USB_RX);
		}
	}
#else
	/* it this is the head of the queue, start i/o ... */
	if (!musb_ep->busy && is_first_entry(&request->list, &musb_ep->req_list))
		musb_ep_restart(musb, request);
#endif

cleanup:
	spin_unlock_irqrestore(&musb->lock, lockflags);
	return status;
}

static int musb_gadget_dequeue(struct usb_ep *ep, struct usb_request *request)
{
	struct musb_ep *musb_ep = to_musb_ep(ep);
	struct musb_request *req = to_musb_request(request);
	struct musb_request *r;
	unsigned long flags;
	int status = 0;
	struct musb *musb = musb_ep->musb;

	if (!ep || !request || to_musb_request(request)->ep != musb_ep)
		return -EINVAL;

	mu3d_dbg(K_INFO, "*************** musb_gadget_dequeue : request 0x%p\n\n\n", request);

	spin_lock_irqsave(&musb->lock, flags);

	list_for_each_entry(r, &musb_ep->req_list, list) {
		if (r == req)
			break;
	}
	if (r != req) {
		dev_dbg(musb->controller, "request %p not queued to %s\n", request, ep->name);
		status = -EINVAL;
		goto done;
	}

	/* if the hardware doesn't have the request, easy ... */
	if (musb_ep->req_list.next != &req->list || musb_ep->busy)
		musb_g_giveback(musb_ep, request, -ECONNRESET);

	/* ... else abort the dma transfer ... */

#ifdef USE_SSUSB_QMU
	else {
		mu3d_hal_flush_qmu(musb, musb_ep->hw_ep->epnum, (musb_ep->is_in ? USB_TX : USB_RX));
		/* is_in--> TX */

		musb_g_giveback(musb_ep, request, -ECONNRESET);

		/* only start qmu, don't need to reset EP */
		mu3d_hal_start_qmu(musb, musb_ep->hw_ep->epnum, (musb_ep->is_in ? USB_TX : USB_RX));
		status = 0;
	}
#else
	/* else if (is_dma_capable() && musb_ep->dma) { */
	/* struct dma_controller *c = musb->dma_controller; */

	/* if (c->channel_abort) */
	/* status = c->channel_abort(musb_ep->dma); */
	/* else */
	/* status = -EBUSY; */
	/* if (status == 0) */
	/* musb_g_giveback(musb_ep, request, -ECONNRESET); */
	/* } */
	else {
		/* NOTE: by sticking to easily tested hardware/driver states,
		 * we leave counting of in-flight packets imprecise.
		 */
		musb_g_giveback(musb_ep, request, -ECONNRESET);
	}
#endif
done:
	spin_unlock_irqrestore(&musb->lock, flags);
	return status;
}

/*
 * Set or clear the halt bit of an endpoint. A halted enpoint won't tx/rx any
 * data but will queue requests.
 *
 * exported to ep0 code
 */
static int musb_gadget_set_halt(struct usb_ep *ep, int value)
{
	struct musb_ep *musb_ep = to_musb_ep(ep);
	u8 epnum = musb_ep->current_epnum;
	struct musb *musb = musb_ep->musb;
	struct musb_hw_ep *hw_ep = musb_ep->hw_ep;
	void __iomem *mbase = musb->mac_base;
	unsigned long flags;
	u32 txcsr0 = 0, rxcsr0 = 0;
	struct musb_request *request;
	int status = 0;

	if (!ep)
		return -EINVAL;

	mu3d_dbg(K_DEBUG, "musb_gadget_set_halt : %s...", ep->name);
	spin_lock_irqsave(&musb->lock, flags);

	if (USB_ENDPOINT_XFER_ISOC == musb_ep->type) {
		status = -EINVAL;
		goto done;
	}


	request = next_request(musb_ep);
	if (value) {
		if (request) {
			dev_dbg(musb->controller, "request in progress, cannot halt %s\n",
				ep->name);
			status = -EAGAIN;
			goto done;
		}
		/* Cannot portably stall with non-empty FIFO */
		if (musb_ep->is_in) {
			txcsr0 = mu3d_readl(hw_ep->addr_txcsr0, 0);
			if (!(txcsr0 & TX_FIFOEMPTY)) {
				dev_dbg(musb->controller, "FIFO busy, cannot halt %s\n", ep->name);
				status = -EAGAIN;
				goto done;
			}
		}
	} else
		musb_ep->wedged = 0;

	/* set/clear the stall and toggle bits */
	dev_dbg(musb->controller, "%s: %s stall\n", ep->name, value ? "set" : "clear");
	if (musb_ep->is_in) {	/* TX */
		txcsr0 = mu3d_readl(hw_ep->addr_txcsr0, 0) & TX_W1C_BITS;

		if (value) {	/* set */
			txcsr0 |= TX_SENDSTALL;
			mu3d_writel(hw_ep->addr_txcsr0, 0, txcsr0);
		} else {	/* clear */

			txcsr0 = (txcsr0 & (~TX_SENDSTALL)) | TX_SENTSTALL;
			/* we need to also clear SENTSTALL to let the EP work normaly. */
			mu3d_writel(hw_ep->addr_txcsr0, 0, txcsr0);

			mu3d_setmsk(mbase, U3D_EP_RST, (BIT16 << epnum));	/* reset TX EP */
			mu3d_clrmsk(mbase, U3D_EP_RST, (BIT16 << epnum));	/* reset reset TX EP */

			/* We cannot flush QMU now, because the MSC gadget will*/
			/*not re-submit the CBW request after clear halt. */
			/* mu3d_hal_flush_qmu(musb, epnum, USB_TX); */
			/* mu3d_hal_restart_qmu(musb, epnum, USB_TX); */
		}

	} else {
		rxcsr0 = mu3d_readl(hw_ep->addr_rxcsr0, 0) & RX_W1C_BITS;

		if (value) {	/* set stall */
			rxcsr0 &= RX_W1C_BITS;
			rxcsr0 |= RX_SENDSTALL;
			mu3d_writel(hw_ep->addr_rxcsr0, 0, rxcsr0);
			/* writel(rxcsr0, musb->endpoints[epnum].addr_rxcsr0); */
		} else {	/* clear stall */

			rxcsr0 = (rxcsr0 & (~RX_SENDSTALL)) | RX_SENTSTALL;
			/* we need to also clear SENTSTALL to let the EP work normaly. */
			mu3d_writel(hw_ep->addr_rxcsr0, 0, rxcsr0);
			/* writel(rxcsr0, musb->endpoints[epnum].addr_rxcsr0); */

			mu3d_setmsk(mbase, U3D_EP_RST, (1 << epnum));	/* reset RX EP */
			mu3d_clrmsk(mbase, U3D_EP_RST, (1 << epnum));	/* reset reset RX EP */
			/* We cannot flush QMU now, because the MSC gadget will*/
			/*not re-submit the CBW request after clear halt. */
			/* mu3d_hal_flush_qmu(musb, epnum, USB_RX); */
			/* mu3d_hal_restart_qmu(musb, epnum, USB_RX); */
		}
	}


	/* maybe start the first request in the queue */
	if (!musb_ep->busy && !value && request) {
		dev_dbg(musb->controller, "restarting the request\n");
		musb_ep_restart(musb, request);
	}

done:
	spin_unlock_irqrestore(&musb->lock, flags);
	return status;
}

/*
 * Sets the halt feature with the clear requests ignored
 */
static int musb_gadget_set_wedge(struct usb_ep *ep)
{
	struct musb_ep *musb_ep = to_musb_ep(ep);

	if (!ep)
		return -EINVAL;

	musb_ep->wedged = 1;

	return usb_ep_set_halt(ep);
}

static int musb_gadget_fifo_status(struct usb_ep *ep)
{
	struct musb_ep *musb_ep = to_musb_ep(ep);
	int retval = -EINVAL;

	if (musb_ep->desc && !musb_ep->is_in) {
		struct musb *musb = musb_ep->musb;
		/* int epnum = musb_ep->current_epnum; */
		unsigned long flags;

		spin_lock_irqsave(&musb->lock, flags);

		/* FIXME return zero unless RXPKTRDY is set */
		retval = mu3d_readl(musb_ep->hw_ep->addr_rxcsr3, 0) >> 16;

		spin_unlock_irqrestore(&musb->lock, flags);
	}
	return retval;
}

static void musb_gadget_fifo_flush(struct usb_ep *ep)
{
	struct musb_ep *musb_ep = to_musb_ep(ep);
	struct musb *musb = musb_ep->musb;
	u8 epnum = musb_ep->current_epnum;
	void __iomem *mbase = musb->mac_base;
	unsigned long flags;
#ifndef USE_SSUSB_QMU		/* we don't enable EP interrupts in QMU mode. */
	u32 int_txe;
#endif
	u32 txcsr0 = 0;

	spin_lock_irqsave(&musb->lock, flags);

	/* disable interrupts */
#ifndef USE_SSUSB_QMU		/* we don't enable EP interrupts in QMU mode. */
	int_txe = mu3d_readl(mbase, U3D_EPIER);
	mu3d_writel(mbase, U3D_EPIECR, (1 << epnum));	/* set clear register */
#endif

	if (musb_ep->is_in) {	/* TX */

#ifdef USE_SSUSB_QMU
		mu3d_hal_flush_qmu(musb, epnum, USB_TX);
		mu3d_hal_restart_qmu(musb, epnum, USB_TX);

#endif
		txcsr0 = mu3d_readl(musb->endpoints[epnum].addr_txcsr0, 0);

		if (!(txcsr0 & TX_FIFOEMPTY)) {
			mu3d_dbg(K_DEBUG, "%s RESET\n", ep->name);
			mu3d_setmsk(mbase, U3D_EP_RST, (BIT16 << epnum));	/* reset TX EP */
			mu3d_clrmsk(mbase, U3D_EP_RST, (BIT16 << epnum));	/* reset reset TX EP */

			/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
		}

	} else {
#ifdef USE_SSUSB_QMU
		mu3d_hal_flush_qmu(musb, epnum, USB_RX);
		mu3d_hal_restart_qmu(musb, epnum, USB_RX);
#endif
		mu3d_dbg(K_DEBUG, "%s RESET\n", ep->name);
		/* os_writew(musb->endpoints[epnum].addr_rxcsr0, rxcsr0 | USB_RXCSR_FLUSHFIFO); */
		/* os_writew(musb->endpoints[epnum].addr_rxcsr0, rxcsr0 & (~USB_RXCSR_FLUSHFIFO)); */
		mu3d_setmsk(mbase, U3D_EP_RST, (1 << epnum));	/* reset RX EP */
		mu3d_clrmsk(mbase, U3D_EP_RST, (1 << epnum));	/* reset reset RX EP */

	}

	/* re-enable interrupt */
#ifndef USE_SSUSB_QMU
	mu3d_writel(mbase, U3D_EPIESR, int_txe);
#endif
	spin_unlock_irqrestore(&musb->lock, flags);
}

static const struct usb_ep_ops musb_ep_ops = {
	.enable = musb_gadget_enable,
	.disable = musb_gadget_disable,
	.alloc_request = musb_alloc_request,
	.free_request = musb_free_request,
	.queue = musb_gadget_queue,
	.dequeue = musb_gadget_dequeue,
	.set_halt = musb_gadget_set_halt,
	.set_wedge = musb_gadget_set_wedge,
	.fifo_status = musb_gadget_fifo_status,
	.fifo_flush = musb_gadget_fifo_flush
};

/* ----------------------------------------------------------------------- */

static int musb_gadget_get_frame(struct usb_gadget *gadget)
{
	struct musb *musb = gadget_to_musb(gadget);

	return (int)mu3d_readl(musb->mac_base, U3D_USB20_FRAME_NUM);
}

static int musb_gadget_wakeup(struct usb_gadget *gadget)
{
	struct musb *musb = gadget_to_musb(gadget);
	unsigned long flags;
	int status = -EINVAL;
	/* u8 devctl; */
	/* int retries; */

	spin_lock_irqsave(&musb->lock, flags);
	mu3d_dbg(K_DEBUG, "musb_gadget_wakeup\n");

	switch (musb->xceiv->state) {
	case OTG_STATE_B_PERIPHERAL:
		/* NOTE:  OTG state machine doesn't include B_SUSPENDED;
		 * that's part of the standard usb 1.1 state machine, and
		 * doesn't affect OTG transitions.
		 */
		if (musb->may_wakeup && musb->is_suspended)
			break;
		goto done;
	case OTG_STATE_B_IDLE:
		/* Start SRP ... OTG not required. */
		status = 0;
		goto done;
	default:
		dev_dbg(musb->controller, "Unhandled wake: %s\n",
			usb_otg_state_string(musb->xceiv->state));
		goto done;
	}

	status = 0;
	mu3d_dbg(K_DEBUG, "****************** musb_gadget_wakeup......\n");
/* mu3d_hal_resume(); */
done:
	spin_unlock_irqrestore(&musb->lock, flags);
	return status;
}

static int musb_gadget_set_self_powered(struct usb_gadget *gadget, int is_selfpowered)
{
	struct musb *musb = gadget_to_musb(gadget);

	musb->is_self_powered = !!is_selfpowered;
	return 0;
}


#if 0
static int musb_gadget_vbus_session(struct usb_gadget *gadget, int is_active)
{
	dev_dbg(musb->controller, "<= %s =>\n", __func__);

	/*
	 * FIXME iff driver's softconnect flag is set (as it is during probe,
	 * though that can clear it), just musb_pullup().
	 */

	return -EINVAL;
}
#endif

static int musb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
{
	struct musb *musb = gadget_to_musb(gadget);

	if (!musb->xceiv->set_power)
		return -EOPNOTSUPP;
	return usb_phy_set_power(musb->xceiv, mA);
}

static int musb_gadget_pullup(struct usb_gadget *gadget, int is_on)
{
	struct musb *musb = gadget_to_musb(gadget);
	unsigned long flags;

	mu3d_dbg(K_INFO, "%s (on-%d)\n", __func__, is_on);

	is_on = !!is_on;
	if (musb->is_active == 0) {
		/* save it for musb_start() to process the request */
		musb->softconnect = is_on;
		mu3d_dbg(K_INFO, "mu3d gadget is inactive(pullup %s)!!\n", is_on ? "on" : "off");
		return 0;
	}

	pm_runtime_get_sync(musb->controller);

	/* NOTE: this assumes we are sensing vbus; we'd rather
	 * not pullup unless the B-session is active.
	 */
	spin_lock_irqsave(&musb->lock, flags);
	if (is_on != musb->softconnect) {
		musb->softconnect = is_on;
		musb_dev_on_off(musb, is_on);
	}
	spin_unlock_irqrestore(&musb->lock, flags);

	pm_runtime_put(musb->controller);

	return 0;
}

static int musb_gadget_start(struct usb_gadget *g, struct usb_gadget_driver *driver);
static int musb_gadget_stop(struct usb_gadget *g, struct usb_gadget_driver *driver);

static const struct usb_gadget_ops musb_gadget_operations = {
	.get_frame = musb_gadget_get_frame,
	.wakeup = musb_gadget_wakeup,
	.set_selfpowered = musb_gadget_set_self_powered,
	/* .vbus_session                = musb_gadget_vbus_session, */
	.vbus_draw = musb_gadget_vbus_draw,
	.pullup = musb_gadget_pullup,
	.udc_start = musb_gadget_start,
	.udc_stop = musb_gadget_stop,
	/*REVISIT-J: Do we need implement "get_config_params" to config U1/U2 */
};

/* ----------------------------------------------------------------------- */

/* Registration */

/* Only this registration code "knows" the rule (from USB standards)
 * about there being only one external upstream port.  It assumes
 * all peripheral ports are external...
 */

#ifdef NEVER
static void musb_gadget_release(struct device *dev)
{
	/* kref_put(WHAT) */
	dev_dbg(dev, "%s\n", __func__);
}
#endif				/* NEVER */


static void init_peripheral_ep(struct musb *musb, struct musb_ep *ep, u8 epnum, int is_in)
{
	struct musb_hw_ep *hw_ep = musb->endpoints + epnum;

	memset(ep, 0, sizeof(*ep));

	ep->current_epnum = epnum;
	ep->musb = musb;
	ep->hw_ep = hw_ep;
	ep->is_in = is_in;

	INIT_LIST_HEAD(&ep->req_list);

	sprintf(ep->name, "ep%d%s", epnum,
		(!epnum || hw_ep->is_shared_fifo) ? "" : (is_in ? "in" : "out"));

	mu3d_dbg(K_DEBUG, "%s, name=%s\n", __func__, ep->name);

	ep->end_point.name = ep->name;
	INIT_LIST_HEAD(&ep->end_point.ep_list);
	if (!epnum) {
		ep->end_point.maxpacket = hw_ep->max_packet_sz_tx;
		ep->end_point.ops = &musb_g_ep0_ops;
		musb->g.ep0 = &ep->end_point;
	} else {
		if (is_in)
			ep->end_point.maxpacket = hw_ep->max_packet_sz_tx;
		else
			ep->end_point.maxpacket = hw_ep->max_packet_sz_rx;
		ep->end_point.ops = &musb_ep_ops;
		list_add_tail(&ep->end_point.ep_list, &musb->g.ep_list);
	}

	mu3d_dbg(K_DEBUG, "%s, name=%s, maxp=%d\n", __func__, ep->end_point.name,
		 ep->end_point.maxpacket);
}

/*
 * Initialize the endpoints exposed to peripheral drivers, with backlinks
 * to the rest of the driver state.
 */
static inline void musb_g_init_endpoints(struct musb *musb)
{
	u8 epnum;
	struct musb_hw_ep *hw_ep;
	unsigned count = 0;

	/* initialize endpoint list just once */
	INIT_LIST_HEAD(&(musb->g.ep_list));

	mu3d_dbg(K_INFO, "%s nr_endpoints=%d\n", __func__, musb->nr_endpoints);

	for (epnum = 0, hw_ep = musb->endpoints; epnum < musb->nr_endpoints; epnum++, hw_ep++) {
		mu3d_dbg(K_INFO, "%s epnum=%d shared_fifo=%d rx_maxp=%d tx_maxp=%d\n",
			 __func__, epnum, hw_ep->is_shared_fifo, hw_ep->max_packet_sz_rx ? : 0,
			 hw_ep->max_packet_sz_tx ? : 0);
		if (hw_ep->is_shared_fifo /* || !epnum */) {
			init_peripheral_ep(musb, &hw_ep->ep_in, epnum, 0);
			count++;
		} else {
			if (hw_ep->max_packet_sz_tx) {
				init_peripheral_ep(musb, &hw_ep->ep_in, epnum, 1);
				count++;
			}
			if (hw_ep->max_packet_sz_rx) {
				init_peripheral_ep(musb, &hw_ep->ep_out, epnum, 0);
				count++;
			}
		}
	}
}

/* called once during driver setup to initialize and link into
 * the driver model; memory is zeroed.
 */
int musb_gadget_setup(struct musb *musb)
{
	int status;

	/* REVISIT minor race:  if (erroneously) setting up two
	 * musb peripherals at the same time, only the bus lock
	 * is probably held.
	 */

	musb->g.ops = &musb_gadget_operations;
	musb->g.max_speed = USB_SPEED_SUPER;
	musb->g.speed = USB_SPEED_UNKNOWN;

	/* this "gadget" abstracts/virtualizes the controller */
	/* dev_set_name(&musb->g.dev, "gadget"); */
	/* musb->g.dev.parent = musb->controller; */
	/* musb->g.dev.dma_mask = musb->controller->dma_mask; */
	/* musb->g.dev.release = musb_gadget_release; */
	musb->g.name = musb_driver_name;

	if (is_otg_enabled(musb))
		musb->g.is_otg = 1;

	musb_g_init_endpoints(musb);

	musb->is_active = 0;
	musb_platform_try_idle(musb, 0);

	/* status = device_register(&musb->g.dev); */
	/* if (status != 0) { */
	/* put_device(&musb->g.dev); */
	/* return status; */
	/* } */

	status = usb_add_gadget_udc(musb->controller, &musb->g);
	if (status)
		goto err;

	return 0;
err:
	musb->g.dev.parent = NULL;
	device_unregister(&musb->g.dev);
	return status;
}

void musb_gadget_cleanup(struct musb *musb)
{
	usb_del_gadget_udc(&musb->g);
	/* if (musb->g.dev.parent) */
	/* device_unregister(&musb->g.dev); */
}

/*
 * Register the gadget driver. Used by gadget drivers when
 * registering themselves with the controller.
 *
 * -EINVAL something went wrong (not driver)
 * -EBUSY another gadget is already using the controller
 * -ENOMEM no memory to perform the operation
 *
 * @param driver the gadget driver
 * @return <0 if error, 0 if everything is fine
 */
static int musb_gadget_start(struct usb_gadget *g, struct usb_gadget_driver *driver)
{
	struct musb *musb = gadget_to_musb(g);
	struct usb_otg *otg = musb->xceiv->otg;
	unsigned long flags;
	int retval = 0;

	mu3d_dbg(K_INFO, "%s %d\n", __func__, __LINE__);

	if (driver->max_speed < USB_SPEED_HIGH) {
		retval = -EINVAL;
		goto err;
	}

	pm_runtime_get_sync(musb->controller);
	mu3d_dbg(K_INFO, "%s %d\n", __func__, __LINE__);

	dev_dbg(musb->controller, "registering driver %s\n", driver->function);

	musb->softconnect = 0;
	musb->gadget_driver = driver;

	spin_lock_irqsave(&musb->lock, flags);
	musb->is_active = 1;

	otg_set_peripheral(otg, &musb->g);
	musb->xceiv->state = OTG_STATE_B_IDLE;

	/**
	* if there is no iddig to detect usb plug in/out on box, start it directly if init as device;
	* if it's on power saving mode and not plug in cable when bootup system,
	* LDO & clock will be disabled.
	*/
	if (musb->ssusb->is_power_saving_mode)
		queue_delayed_work(musb->wq, &musb->connection_work, 0);
	else if (musb->start_mu3d)
		musb_start(musb);
	else if (is_init_host_for_manual_otg(musb->ssusb))
		mu3d_hal_ssusb_dis(musb);

	spin_unlock_irqrestore(&musb->lock, flags);

	if (musb->xceiv->last_event == USB_EVENT_NONE)
		pm_runtime_put(musb->controller);

	return 0;

err:
	return retval;
}

static void stop_activity(struct musb *musb, struct usb_gadget_driver *driver)
{
	int i;
	struct musb_hw_ep *hw_ep;

	/* don't disconnect if it's not connected */
	if (musb->g.speed == USB_SPEED_UNKNOWN)
		driver = NULL;
	else
		musb->g.speed = USB_SPEED_UNKNOWN;

	/* deactivate the hardware */
	if (musb->softconnect) {
		musb->softconnect = 0;
		musb_dev_on_off(musb, 0);
	}
	musb_stop(musb);

	/* killing any outstanding requests will quiesce the driver;
	 * then report disconnect
	 */
	if (driver) {
		for (i = 0, hw_ep = musb->endpoints; i < musb->nr_endpoints; i++, hw_ep++) {
			if (hw_ep->is_shared_fifo /* || !epnum */) {
				nuke(&hw_ep->ep_in, -ESHUTDOWN);
			} else {
				if (hw_ep->max_packet_sz_tx)
					nuke(&hw_ep->ep_in, -ESHUTDOWN);
				if (hw_ep->max_packet_sz_rx)
					nuke(&hw_ep->ep_out, -ESHUTDOWN);
			}
		}
	}
}

/*
 * Unregister the gadget driver. Used by gadget drivers when
 * unregistering themselves from the controller.
 *
 * @param driver the gadget driver to unregister
 */
static int musb_gadget_stop(struct usb_gadget *g, struct usb_gadget_driver *driver)
{
	struct musb *musb = gadget_to_musb(g);
	unsigned long flags;

	if (musb->xceiv->last_event == USB_EVENT_NONE)
		pm_runtime_get_sync(musb->controller);

	mu3d_dbg(K_INFO, "%s\n", __func__);

	/*
	 * REVISIT always use otg_set_peripheral() here too;
	 * this needs to shut down the OTG engine.
	 */

	spin_lock_irqsave(&musb->lock, flags);

	/* musb_hnp_stop(musb); */

	musb_gadget_vbus_draw(&musb->g, 0);

	musb->xceiv->state = OTG_STATE_UNDEFINED;
	stop_activity(musb, driver);
	otg_set_peripheral(musb->xceiv->otg, NULL);

	dev_dbg(musb->controller, "unregistering driver %s\n", driver->function);

	musb->is_active = 0;
	musb_platform_try_idle(musb, 0);
	spin_unlock_irqrestore(&musb->lock, flags);

	if (musb->start_mu3d)
		musb_stop(musb);

	pm_runtime_put(musb->controller);

	return 0;
}

/* ----------------------------------------------------------------------- */

/* lifecycle operations called through plat_uds.c */

void musb_g_resume(struct musb *musb)
{
	musb->is_suspended = 0;
	switch (musb->xceiv->state) {
	case OTG_STATE_B_IDLE:
		break;
		/* case OTG_STATE_B_WAIT_ACON: */
	case OTG_STATE_B_PERIPHERAL:
		musb->is_active = 1;
		if (musb->gadget_driver && musb->gadget_driver->resume) {
			spin_unlock(&musb->lock);
			musb->gadget_driver->resume(&musb->g);
			spin_lock(&musb->lock);
		}
		break;
	default:
		mu3d_dbg(K_ERR, "unhandled RESUME transition (%s)\n",
			 usb_otg_state_string(musb->xceiv->state));
	}
}

/* called when SOF packets stop for 3+ msec */
void musb_g_suspend(struct musb *musb)
{
	u32 devctl;

	devctl = mu3d_readl(musb->mac_base, U3D_DEVICE_CONTROL);
	dev_notice(musb->controller, "devctl %02x\n", devctl);

	switch (musb->xceiv->state) {
	case OTG_STATE_B_IDLE:
		if ((devctl & VBUS) == USB_DEVCTL_VBUSVALID)
			musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
		break;
	case OTG_STATE_B_PERIPHERAL:
		musb->is_suspended = 1;
		if (musb->gadget_driver && musb->gadget_driver->suspend) {
			spin_unlock(&musb->lock);
			musb->gadget_driver->suspend(&musb->g);
			spin_lock(&musb->lock);
		}
		musb_sync_with_bat(musb, USB_SUSPEND);	/* annonce to battery */
		break;
	default:
		/* REVISIT if B_HOST, clear DEVCTL.HOSTREQ;
		 * A_PERIPHERAL may need care too
		 */
		mu3d_dbg(K_ERR, "unhandled SUSPEND transition (%s)\n",
			 usb_otg_state_string(musb->xceiv->state));
	}
}

/* Called during SRP */
void musb_g_wakeup(struct musb *musb)
{
	musb_gadget_wakeup(&musb->g);
}

/* called when VBUS drops below session threshold, and in other cases */
void musb_g_disconnect(struct musb *musb)
{
	u32 devctl = mu3d_readl(musb->mac_base, U3D_DEVICE_CONTROL);

	dev_notice(musb->controller, "devctl %02x\n", devctl);

	/* clear HR */
	/* marked off for 3.0 reset device test */
	/* os_writel(U3D_DEVICE_CONTROL, devctl & SESSION); */

	/* don't draw vbus until new b-default session */
	(void)musb_gadget_vbus_draw(&musb->g, 0);

	musb->g.speed = USB_SPEED_UNKNOWN;
	if (musb->gadget_driver && musb->gadget_driver->disconnect) {
		spin_unlock(&musb->lock);
		musb->gadget_driver->disconnect(&musb->g);
		spin_lock(&musb->lock);
	}

	switch (musb->xceiv->state) {
	default:
		dev_dbg(musb->controller, "Unhandled disconnect %s, setting a_idle\n",
			usb_otg_state_string(musb->xceiv->state));
		break;

	case OTG_STATE_B_PERIPHERAL:
	case OTG_STATE_B_IDLE:
		musb->xceiv->state = OTG_STATE_B_IDLE;
		break;
	case OTG_STATE_B_SRP_INIT:
		break;
	}

	musb->is_active = 0;
}


void musb_conifg_ep0(struct musb *musb)
{
	void __iomem *mbase = musb->mac_base;

	mu3d_dbg(K_DEBUG, "U3D_DEVICE_CONF: %x\n", mu3d_readl(mbase, U3D_DEVICE_CONF));

	if (mu3d_readl(mbase, U3D_DEVICE_CONF) & HW_USB2_3_SEL) {	/* SS */
		musb->g.speed = USB_SPEED_SUPER;
		musb->g.ep0->maxpacket = 512;

		mu3d_dbg(K_INFO, "musb_g_reset musb->g.speed: super\n");
		ep0_setup(musb, musb->endpoints, &ep0_cfg_u3);
	} else {		/* HS, FS */
		musb->g.speed = (u8) (mu3d_readl(mbase, U3D_POWER_MANAGEMENT) & HS_MODE)
		    ? USB_SPEED_HIGH : USB_SPEED_FULL;
		musb->g.ep0->maxpacket = 64;

		mu3d_dbg(K_INFO, "musb_g_reset musb->g.speed: %s\n",
			 (musb->g.speed == USB_SPEED_HIGH) ? "high" : "full");
		ep0_setup(musb, musb->endpoints, &ep0_cfg_u2);
	}

	mu3d_dbg(K_DEBUG, "U3D_EP0CSR: %x\n", mu3d_readl(mbase, U3D_EP0CSR));
	mu3d_dbg(K_DEBUG, "U3D_RXCOUNT0: %x\n", mu3d_readl(mbase, U3D_RXCOUNT0));
}

void musb_g_reset(struct musb *musb) __releases(musb->lock) __acquires(musb->lock)
{
	/* u32 devctl = os_readl(U3D_DEVICE_CONTROL); */

	/* it may greater than 2.5mA , but it should meet the spec's requirement !! */
	if (musb->test_mode == 0)
		musb_sync_with_bat(musb, USB_UNCONFIGURED);

	mu3d_hal_unfigured_ep(musb);

	/* report disconnect, if we didn't already (flushing EP state) */
	if (musb->g.speed != USB_SPEED_UNKNOWN)
		musb_g_disconnect(musb);

	/* clear HR */
	/* else if (devctl & HOSTREQ) { */
	/* marked off for 3.0 reset device test */
	/* os_writel(U3D_DEVICE_CONTROL, SESSION); */

	/* } */

	musb_conifg_ep0(musb);
	/* start in USB_STATE_DEFAULT */
	musb->is_active = 1;
	musb->is_suspended = 0;
	/* MUSB_DEV_MODE(musb); */
	musb->address = 0;
	musb->ep0_state = MUSB_EP0_STAGE_SETUP;

	musb->may_wakeup = 0;
	musb->g.b_hnp_enable = 0;
	musb->g.a_alt_hnp_support = 0;
	musb->g.a_hnp_support = 0;

	/* Normal reset, as B-Device;
	 * or else after HNP, as A-Device
	 */
#if 0
	if (devctl & B_DEV) {
		musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
		musb->g.is_a_peripheral = 0;
	} else if (is_otg_enabled(musb)) {
		musb->xceiv->state = OTG_STATE_A_PERIPHERAL;
		musb->g.is_a_peripheral = 1;
	} else
		WARN_ON(1);
#endif
	/* only as b-peripheral */
	musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
	musb->g.is_a_peripheral = 0;

	/* start with default limits on VBUS power draw */
	(void)musb_gadget_vbus_draw(&musb->g, is_otg_enabled(musb) ? 8 : 100);
}