Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2095 insertions, 0 deletions

diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
new file mode 100644
index 000000000..8dc657c71
--- /dev/null
+++ b/drivers/usb/musb/musb_gadget.c
@@ -0,0 +1,2095 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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>
+ */
+
+#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 "musb_trace.h"
+
+
+/* ----------------------------------------------------------------------- */
+
+#define is_buffer_mapped(req) (is_dma_capable() && \
+					(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)
+{
+	int compatible = true;
+	struct dma_controller *dma = musb->dma_controller;
+
+	request->map_state = UN_MAPPED;
+
+	if (!is_dma_capable() || !musb_ep->dma)
+		return;
+
+	/* Check if DMA engine can handle this request.
+	 * DMA code must reject the USB request explicitly.
+	 * Default behaviour is to map the request.
+	 */
+	if (dma->is_compatible)
+		compatible = dma->is_compatible(musb_ep->dma,
+				musb_ep->packet_sz, request->request.buf,
+				request->request.length);
+	if (!compatible)
+		return;
+
+	if (request->request.dma == DMA_ADDR_INVALID) {
+		dma_addr_t dma_addr;
+		int ret;
+
+		dma_addr = dma_map_single(
+				musb->controller,
+				request->request.buf,
+				request->request.length,
+				request->tx
+					? DMA_TO_DEVICE
+					: DMA_FROM_DEVICE);
+		ret = dma_mapping_error(musb->controller, dma_addr);
+		if (ret)
+			return;
+
+		request->request.dma = dma_addr;
+		request->map_state = MUSB_MAPPED;
+	} 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;
+	}
+}
+
+/* Unmap the buffer from dma and maps it back to cpu */
+static inline void unmap_dma_buffer(struct musb_request *request,
+				struct musb *musb)
+{
+	struct musb_ep *musb_ep = request->ep;
+
+	if (!is_buffer_mapped(request) || !musb_ep->dma)
+		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) {
+		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;
+	} else { /* PRE_MAPPED */
+		dma_sync_single_for_cpu(musb->controller,
+			request->request.dma,
+			request->request.length,
+			request->tx
+				? DMA_TO_DEVICE
+				: DMA_FROM_DEVICE);
+	}
+	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;
+
+	ep->busy = 1;
+	spin_unlock(&musb->lock);
+
+	if (!dma_mapping_error(&musb->g.dev, request->dma))
+		unmap_dma_buffer(req, musb);
+
+	trace_musb_req_gb(req);
+	usb_gadget_giveback_request(&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		*musb = ep->musb;
+	struct musb_request	*req = NULL;
+	void __iomem *epio = ep->musb->endpoints[ep->current_epnum].regs;
+
+	ep->busy = 1;
+
+	if (is_dma_capable() && ep->dma) {
+		struct dma_controller	*c = ep->musb->dma_controller;
+		int value;
+
+		if (ep->is_in) {
+			/*
+			 * The programming guide says that we must not clear
+			 * the DMAMODE bit before DMAENAB, so we only
+			 * clear it in the second write...
+			 */
+			musb_writew(epio, MUSB_TXCSR,
+				    MUSB_TXCSR_DMAMODE | MUSB_TXCSR_FLUSHFIFO);
+			musb_writew(epio, MUSB_TXCSR,
+					0 | MUSB_TXCSR_FLUSHFIFO);
+		} else {
+			musb_writew(epio, MUSB_RXCSR,
+					0 | MUSB_RXCSR_FLUSHFIFO);
+			musb_writew(epio, MUSB_RXCSR,
+					0 | MUSB_RXCSR_FLUSHFIFO);
+		}
+
+		value = c->channel_abort(ep->dma);
+		musb_dbg(musb, "%s: abort DMA --> %d", ep->name, value);
+		c->channel_release(ep->dma);
+		ep->dma = NULL;
+	}
+
+	while (!list_empty(&ep->req_list)) {
+		req = list_first_entry(&ep->req_list, struct musb_request, list);
+		musb_g_giveback(ep, &req->request, status);
+	}
+}
+
+/* ----------------------------------------------------------------------- */
+
+/* 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;
+}
+
+/*
+ * 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;
+	void __iomem		*epio = musb->endpoints[epnum].regs;
+	struct usb_request	*request;
+	u16			fifo_count = 0, csr;
+	int			use_dma = 0;
+
+	musb_ep = req->ep;
+
+	/* Check if EP is disabled */
+	if (!musb_ep->desc) {
+		musb_dbg(musb, "ep:%s disabled - ignore request",
+						musb_ep->end_point.name);
+		return;
+	}
+
+	/* we shouldn't get here while DMA is active ... but we do ... */
+	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
+		musb_dbg(musb, "dma pending...");
+		return;
+	}
+
+	/* read TXCSR before */
+	csr = musb_readw(epio, MUSB_TXCSR);
+
+	request = &req->request;
+	fifo_count = min(max_ep_writesize(musb, musb_ep),
+			(int)(request->length - request->actual));
+
+	if (csr & MUSB_TXCSR_TXPKTRDY) {
+		musb_dbg(musb, "%s old packet still ready , txcsr %03x",
+				musb_ep->end_point.name, csr);
+		return;
+	}
+
+	if (csr & MUSB_TXCSR_P_SENDSTALL) {
+		musb_dbg(musb, "%s stalling, txcsr %03x",
+				musb_ep->end_point.name, csr);
+		return;
+	}
+
+	musb_dbg(musb, "hw_ep%d, maxpacket %d, fifo count %d, txcsr %03x",
+			epnum, musb_ep->packet_sz, fifo_count,
+			csr);
+
+#ifndef	CONFIG_MUSB_PIO_ONLY
+	if (is_buffer_mapped(req)) {
+		struct dma_controller	*c = musb->dma_controller;
+		size_t request_size;
+
+		/* setup DMA, then program endpoint CSR */
+		request_size = min_t(size_t, request->length - request->actual,
+					musb_ep->dma->max_len);
+
+		use_dma = (request->dma != DMA_ADDR_INVALID && request_size);
+
+		/* MUSB_TXCSR_P_ISO is still set correctly */
+
+		if (musb_dma_inventra(musb) || musb_dma_ux500(musb)) {
+			if (request_size < musb_ep->packet_sz)
+				musb_ep->dma->desired_mode = 0;
+			else
+				musb_ep->dma->desired_mode = 1;
+
+			use_dma = use_dma && c->channel_program(
+					musb_ep->dma, musb_ep->packet_sz,
+					musb_ep->dma->desired_mode,
+					request->dma + request->actual, request_size);
+			if (use_dma) {
+				if (musb_ep->dma->desired_mode == 0) {
+					/*
+					 * We must not clear the DMAMODE bit
+					 * before the DMAENAB bit -- and the
+					 * latter doesn't always get cleared
+					 * before we get here...
+					 */
+					csr &= ~(MUSB_TXCSR_AUTOSET
+						| MUSB_TXCSR_DMAENAB);
+					musb_writew(epio, MUSB_TXCSR, csr
+						| MUSB_TXCSR_P_WZC_BITS);
+					csr &= ~MUSB_TXCSR_DMAMODE;
+					csr |= (MUSB_TXCSR_DMAENAB |
+							MUSB_TXCSR_MODE);
+					/* against programming guide */
+				} else {
+					csr |= (MUSB_TXCSR_DMAENAB
+							| MUSB_TXCSR_DMAMODE
+							| MUSB_TXCSR_MODE);
+					/*
+					 * Enable Autoset according to table
+					 * below
+					 * bulk_split hb_mult	Autoset_Enable
+					 *	0	0	Yes(Normal)
+					 *	0	>0	No(High BW ISO)
+					 *	1	0	Yes(HS bulk)
+					 *	1	>0	Yes(FS bulk)
+					 */
+					if (!musb_ep->hb_mult ||
+					    can_bulk_split(musb,
+							   musb_ep->type))
+						csr |= MUSB_TXCSR_AUTOSET;
+				}
+				csr &= ~MUSB_TXCSR_P_UNDERRUN;
+
+				musb_writew(epio, MUSB_TXCSR, csr);
+			}
+		}
+
+		if (is_cppi_enabled(musb)) {
+			/* program endpoint CSR first, then setup DMA */
+			csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
+			csr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE |
+				MUSB_TXCSR_MODE;
+			musb_writew(epio, MUSB_TXCSR, (MUSB_TXCSR_P_WZC_BITS &
+						~MUSB_TXCSR_P_UNDERRUN) | csr);
+
+			/* ensure writebuffer is empty */
+			csr = musb_readw(epio, MUSB_TXCSR);
+
+			/*
+			 * NOTE host side sets DMAENAB later than this; both are
+			 * OK since the transfer dma glue (between CPPI and
+			 * Mentor fifos) just tells CPPI it could start. Data
+			 * only moves to the USB TX fifo when both fifos are
+			 * ready.
+			 */
+			/*
+			 * "mode" is irrelevant here; handle terminating ZLPs
+			 * like PIO does, since the hardware RNDIS mode seems
+			 * unreliable except for the
+			 * last-packet-is-already-short case.
+			 */
+			use_dma = use_dma && c->channel_program(
+					musb_ep->dma, musb_ep->packet_sz,
+					0,
+					request->dma + request->actual,
+					request_size);
+			if (!use_dma) {
+				c->channel_release(musb_ep->dma);
+				musb_ep->dma = NULL;
+				csr &= ~MUSB_TXCSR_DMAENAB;
+				musb_writew(epio, MUSB_TXCSR, csr);
+				/* invariant: prequest->buf is non-null */
+			}
+		} else if (tusb_dma_omap(musb))
+			use_dma = use_dma && c->channel_program(
+					musb_ep->dma, musb_ep->packet_sz,
+					request->zero,
+					request->dma + request->actual,
+					request_size);
+	}
+#endif
+
+	if (!use_dma) {
+		/*
+		 * Unmap the dma buffer back to cpu if dma channel
+		 * programming fails
+		 */
+		unmap_dma_buffer(req, musb);
+
+		musb_write_fifo(musb_ep->hw_ep, fifo_count,
+				(u8 *) (request->buf + request->actual));
+		request->actual += fifo_count;
+		csr |= MUSB_TXCSR_TXPKTRDY;
+		csr &= ~MUSB_TXCSR_P_UNDERRUN;
+		musb_writew(epio, MUSB_TXCSR, csr);
+	}
+
+	/* host may already have the data when this message shows... */
+	musb_dbg(musb, "%s TX/IN %s len %d/%d, txcsr %04x, fifo %d/%d",
+			musb_ep->end_point.name, use_dma ? "dma" : "pio",
+			request->actual, request->length,
+			musb_readw(epio, MUSB_TXCSR),
+			fifo_count,
+			musb_readw(epio, MUSB_TXMAXP));
+}
+
+/*
+ * FIFO state update (e.g. data ready).
+ * Called from IRQ,  with controller locked.
+ */
+void musb_g_tx(struct musb *musb, u8 epnum)
+{
+	u16			csr;
+	struct musb_request	*req;
+	struct usb_request	*request;
+	u8 __iomem		*mbase = musb->mregs;
+	struct musb_ep		*musb_ep = &musb->endpoints[epnum].ep_in;
+	void __iomem		*epio = musb->endpoints[epnum].regs;
+	struct dma_channel	*dma;
+
+	musb_ep_select(mbase, epnum);
+	req = next_request(musb_ep);
+	request = &req->request;
+
+	csr = musb_readw(epio, MUSB_TXCSR);
+	musb_dbg(musb, "<== %s, txcsr %04x", musb_ep->end_point.name, csr);
+
+	dma = is_dma_capable() ? musb_ep->dma : NULL;
+
+	/*
+	 * REVISIT: for high bandwidth, MUSB_TXCSR_P_INCOMPTX
+	 * probably rates reporting as a host error.
+	 */
+	if (csr & MUSB_TXCSR_P_SENTSTALL) {
+		csr |=	MUSB_TXCSR_P_WZC_BITS;
+		csr &= ~MUSB_TXCSR_P_SENTSTALL;
+		musb_writew(epio, MUSB_TXCSR, csr);
+		return;
+	}
+
+	if (csr & MUSB_TXCSR_P_UNDERRUN) {
+		/* We NAKed, no big deal... little reason to care. */
+		csr |=	 MUSB_TXCSR_P_WZC_BITS;
+		csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
+		musb_writew(epio, MUSB_TXCSR, csr);
+		dev_vdbg(musb->controller, "underrun on ep%d, req %p\n",
+				epnum, request);
+	}
+
+	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
+		/*
+		 * SHOULD NOT HAPPEN... has with CPPI though, after
+		 * changing SENDSTALL (and other cases); harmless?
+		 */
+		musb_dbg(musb, "%s dma still busy?", musb_ep->end_point.name);
+		return;
+	}
+
+	if (request) {
+
+		trace_musb_req_tx(req);
+
+		if (dma && (csr & MUSB_TXCSR_DMAENAB)) {
+			csr |= MUSB_TXCSR_P_WZC_BITS;
+			csr &= ~(MUSB_TXCSR_DMAENAB | MUSB_TXCSR_P_UNDERRUN |
+				 MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_AUTOSET);
+			musb_writew(epio, MUSB_TXCSR, csr);
+			/* Ensure writebuffer is empty. */
+			csr = musb_readw(epio, MUSB_TXCSR);
+			request->actual += musb_ep->dma->actual_len;
+			musb_dbg(musb, "TXCSR%d %04x, DMA off, len %zu, req %p",
+				epnum, csr, musb_ep->dma->actual_len, 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 (csr & MUSB_TXCSR_TXPKTRDY)
+				return;
+
+			musb_writew(epio, MUSB_TXCSR, MUSB_TXCSR_MODE
+					| MUSB_TXCSR_TXPKTRDY);
+			request->zero = 0;
+		}
+
+		if (request->actual == request->length) {
+			musb_g_giveback(musb_ep, request, 0);
+			/*
+			 * In the giveback function the MUSB lock is
+			 * released and acquired after sometime. During
+			 * this time period the INDEX register could get
+			 * changed by the gadget_queue function especially
+			 * on SMP systems. Reselect the INDEX to be sure
+			 * we are reading/modifying the right registers
+			 */
+			musb_ep_select(mbase, epnum);
+			req = musb_ep->desc ? next_request(musb_ep) : NULL;
+			if (!req) {
+				musb_dbg(musb, "%s idle now",
+					musb_ep->end_point.name);
+				return;
+			}
+		}
+
+		txstate(musb, req);
+	}
+}
+
+/* ------------------------------------------------------------ */
+
+/*
+ * 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;
+	void __iomem		*epio = musb->endpoints[epnum].regs;
+	unsigned		len = 0;
+	u16			fifo_count;
+	u16			csr = musb_readw(epio, MUSB_RXCSR);
+	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
+	u8			use_mode_1;
+
+	if (hw_ep->is_shared_fifo)
+		musb_ep = &hw_ep->ep_in;
+	else
+		musb_ep = &hw_ep->ep_out;
+
+	fifo_count = musb_ep->packet_sz;
+
+	/* Check if EP is disabled */
+	if (!musb_ep->desc) {
+		musb_dbg(musb, "ep:%s disabled - ignore request",
+						musb_ep->end_point.name);
+		return;
+	}
+
+	/* We shouldn't get here while DMA is active, but we do... */
+	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
+		musb_dbg(musb, "DMA pending...");
+		return;
+	}
+
+	if (csr & MUSB_RXCSR_P_SENDSTALL) {
+		musb_dbg(musb, "%s stalling, RXCSR %04x",
+		    musb_ep->end_point.name, csr);
+		return;
+	}
+
+	if (is_cppi_enabled(musb) && is_buffer_mapped(req)) {
+		struct dma_controller	*c = musb->dma_controller;
+		struct dma_channel	*channel = musb_ep->dma;
+
+		/* NOTE:  CPPI won't actually stop advancing the DMA
+		 * queue after short packet transfers, so this is almost
+		 * always going to run as IRQ-per-packet DMA so that
+		 * faults will be handled correctly.
+		 */
+		if (c->channel_program(channel,
+				musb_ep->packet_sz,
+				!request->short_not_ok,
+				request->dma + request->actual,
+				request->length - request->actual)) {
+
+			/* make sure that if an rxpkt arrived after the irq,
+			 * the cppi engine will be ready to take it as soon
+			 * as DMA is enabled
+			 */
+			csr &= ~(MUSB_RXCSR_AUTOCLEAR
+					| MUSB_RXCSR_DMAMODE);
+			csr |= MUSB_RXCSR_DMAENAB | MUSB_RXCSR_P_WZC_BITS;
+			musb_writew(epio, MUSB_RXCSR, csr);
+			return;
+		}
+	}
+
+	if (csr & MUSB_RXCSR_RXPKTRDY) {
+		fifo_count = musb_readw(epio, MUSB_RXCOUNT);
+
+		/*
+		 * Enable Mode 1 on RX transfers only when short_not_ok flag
+		 * is set. Currently short_not_ok flag is set only from
+		 * file_storage and f_mass_storage drivers
+		 */
+
+		if (request->short_not_ok && fifo_count == musb_ep->packet_sz)
+			use_mode_1 = 1;
+		else
+			use_mode_1 = 0;
+
+		if (request->actual < request->length) {
+			if (!is_buffer_mapped(req))
+				goto buffer_aint_mapped;
+
+			if (musb_dma_inventra(musb)) {
+				struct dma_controller	*c;
+				struct dma_channel	*channel;
+				int			use_dma = 0;
+				unsigned int transfer_size;
+
+				c = musb->dma_controller;
+				channel = musb_ep->dma;
+
+	/* We use DMA Req mode 0 in rx_csr, and DMA controller operates in
+	 * mode 0 only. So we do not get endpoint interrupts due to DMA
+	 * completion. We only get interrupts from DMA controller.
+	 *
+	 * We could operate in DMA mode 1 if we knew the size of the tranfer
+	 * in advance. For mass storage class, request->length = what the host
+	 * sends, so that'd work.  But for pretty much everything else,
+	 * request->length is routinely more than what the host sends. For
+	 * most these gadgets, end of is signified either by a short packet,
+	 * or filling the last byte of the buffer.  (Sending extra data in
+	 * that last pckate should trigger an overflow fault.)  But in mode 1,
+	 * we don't get DMA completion interrupt for short packets.
+	 *
+	 * Theoretically, we could enable DMAReq irq (MUSB_RXCSR_DMAMODE = 1),
+	 * to get endpoint interrupt on every DMA req, but that didn't seem
+	 * to work reliably.
+	 *
+	 * REVISIT an updated g_file_storage can set req->short_not_ok, which
+	 * then becomes usable as a runtime "use mode 1" hint...
+	 */
+
+				/* Experimental: Mode1 works with mass storage use cases */
+				if (use_mode_1) {
+					csr |= MUSB_RXCSR_AUTOCLEAR;
+					musb_writew(epio, MUSB_RXCSR, csr);
+					csr |= MUSB_RXCSR_DMAENAB;
+					musb_writew(epio, MUSB_RXCSR, csr);
+
+					/*
+					 * this special sequence (enabling and then
+					 * disabling MUSB_RXCSR_DMAMODE) is required
+					 * to get DMAReq to activate
+					 */
+					musb_writew(epio, MUSB_RXCSR,
+						csr | MUSB_RXCSR_DMAMODE);
+					musb_writew(epio, MUSB_RXCSR, csr);
+
+					transfer_size = min_t(unsigned int,
+							request->length -
+							request->actual,
+							channel->max_len);
+					musb_ep->dma->desired_mode = 1;
+				} else {
+					if (!musb_ep->hb_mult &&
+						musb_ep->hw_ep->rx_double_buffered)
+						csr |= MUSB_RXCSR_AUTOCLEAR;
+					csr |= MUSB_RXCSR_DMAENAB;
+					musb_writew(epio, MUSB_RXCSR, csr);
+
+					transfer_size = min(request->length - request->actual,
+							(unsigned)fifo_count);
+					musb_ep->dma->desired_mode = 0;
+				}
+
+				use_dma = c->channel_program(
+						channel,
+						musb_ep->packet_sz,
+						channel->desired_mode,
+						request->dma
+						+ request->actual,
+						transfer_size);
+
+				if (use_dma)
+					return;
+			}
+
+			if ((musb_dma_ux500(musb)) &&
+				(request->actual < request->length)) {
+
+				struct dma_controller *c;
+				struct dma_channel *channel;
+				unsigned int transfer_size = 0;
+
+				c = musb->dma_controller;
+				channel = musb_ep->dma;
+
+				/* In case first packet is short */
+				if (fifo_count < musb_ep->packet_sz)
+					transfer_size = fifo_count;
+				else if (request->short_not_ok)
+					transfer_size =	min_t(unsigned int,
+							request->length -
+							request->actual,
+							channel->max_len);
+				else
+					transfer_size = min_t(unsigned int,
+							request->length -
+							request->actual,
+							(unsigned)fifo_count);
+
+				csr &= ~MUSB_RXCSR_DMAMODE;
+				csr |= (MUSB_RXCSR_DMAENAB |
+					MUSB_RXCSR_AUTOCLEAR);
+
+				musb_writew(epio, MUSB_RXCSR, csr);
+
+				if (transfer_size <= musb_ep->packet_sz) {
+					musb_ep->dma->desired_mode = 0;
+				} else {
+					musb_ep->dma->desired_mode = 1;
+					/* Mode must be set after DMAENAB */
+					csr |= MUSB_RXCSR_DMAMODE;
+					musb_writew(epio, MUSB_RXCSR, csr);
+				}
+
+				if (c->channel_program(channel,
+							musb_ep->packet_sz,
+							channel->desired_mode,
+							request->dma
+							+ request->actual,
+							transfer_size))
+
+					return;
+			}
+
+			len = request->length - request->actual;
+			musb_dbg(musb, "%s OUT/RX pio fifo %d/%d, maxpacket %d",
+					musb_ep->end_point.name,
+					fifo_count, len,
+					musb_ep->packet_sz);
+
+			fifo_count = min_t(unsigned, len, fifo_count);
+
+			if (tusb_dma_omap(musb)) {
+				struct dma_controller *c = musb->dma_controller;
+				struct dma_channel *channel = musb_ep->dma;
+				u32 dma_addr = request->dma + request->actual;
+				int ret;
+
+				ret = c->channel_program(channel,
+						musb_ep->packet_sz,
+						channel->desired_mode,
+						dma_addr,
+						fifo_count);
+				if (ret)
+					return;
+			}
+
+			/*
+			 * Unmap the dma buffer back to cpu if dma channel
+			 * programming fails. This buffer is mapped if the
+			 * channel allocation is successful
+			 */
+			unmap_dma_buffer(req, musb);
+
+			/*
+			 * Clear DMAENAB and AUTOCLEAR for the
+			 * PIO mode transfer
+			 */
+			csr &= ~(MUSB_RXCSR_DMAENAB | MUSB_RXCSR_AUTOCLEAR);
+			musb_writew(epio, MUSB_RXCSR, csr);
+
+buffer_aint_mapped:
+			fifo_count = min_t(unsigned int,
+					request->length - request->actual,
+					(unsigned int)fifo_count);
+			musb_read_fifo(musb_ep->hw_ep, fifo_count, (u8 *)
+					(request->buf + request->actual));
+			request->actual += fifo_count;
+
+			/* REVISIT if we left anything in the fifo, flush
+			 * it and report -EOVERFLOW
+			 */
+
+			/* ack the read! */
+			csr |= MUSB_RXCSR_P_WZC_BITS;
+			csr &= ~MUSB_RXCSR_RXPKTRDY;
+			musb_writew(epio, MUSB_RXCSR, csr);
+		}
+	}
+
+	/* 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)
+{
+	u16			csr;
+	struct musb_request	*req;
+	struct usb_request	*request;
+	void __iomem		*mbase = musb->mregs;
+	struct musb_ep		*musb_ep;
+	void __iomem		*epio = musb->endpoints[epnum].regs;
+	struct dma_channel	*dma;
+	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
+
+	if (hw_ep->is_shared_fifo)
+		musb_ep = &hw_ep->ep_in;
+	else
+		musb_ep = &hw_ep->ep_out;
+
+	musb_ep_select(mbase, epnum);
+
+	req = next_request(musb_ep);
+	if (!req)
+		return;
+
+	trace_musb_req_rx(req);
+	request = &req->request;
+
+	csr = musb_readw(epio, MUSB_RXCSR);
+	dma = is_dma_capable() ? musb_ep->dma : NULL;
+
+	musb_dbg(musb, "<== %s, rxcsr %04x%s %p", musb_ep->end_point.name,
+			csr, dma ? " (dma)" : "", request);
+
+	if (csr & MUSB_RXCSR_P_SENTSTALL) {
+		csr |= MUSB_RXCSR_P_WZC_BITS;
+		csr &= ~MUSB_RXCSR_P_SENTSTALL;
+		musb_writew(epio, MUSB_RXCSR, csr);
+		return;
+	}
+
+	if (csr & MUSB_RXCSR_P_OVERRUN) {
+		/* csr |= MUSB_RXCSR_P_WZC_BITS; */
+		csr &= ~MUSB_RXCSR_P_OVERRUN;
+		musb_writew(epio, MUSB_RXCSR, csr);
+
+		musb_dbg(musb, "%s iso overrun on %p", musb_ep->name, request);
+		if (request->status == -EINPROGRESS)
+			request->status = -EOVERFLOW;
+	}
+	if (csr & MUSB_RXCSR_INCOMPRX) {
+		/* REVISIT not necessarily an error */
+		musb_dbg(musb, "%s, incomprx", musb_ep->end_point.name);
+	}
+
+	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
+		/* "should not happen"; likely RXPKTRDY pending for DMA */
+		musb_dbg(musb, "%s busy, csr %04x",
+			musb_ep->end_point.name, csr);
+		return;
+	}
+
+	if (dma && (csr & MUSB_RXCSR_DMAENAB)) {
+		csr &= ~(MUSB_RXCSR_AUTOCLEAR
+				| MUSB_RXCSR_DMAENAB
+				| MUSB_RXCSR_DMAMODE);
+		musb_writew(epio, MUSB_RXCSR,
+			MUSB_RXCSR_P_WZC_BITS | csr);
+
+		request->actual += musb_ep->dma->actual_len;
+
+#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
+	defined(CONFIG_USB_UX500_DMA)
+		/* Autoclear doesn't clear RxPktRdy for short packets */
+		if ((dma->desired_mode == 0 && !hw_ep->rx_double_buffered)
+				|| (dma->actual_len
+					& (musb_ep->packet_sz - 1))) {
+			/* ack the read! */
+			csr &= ~MUSB_RXCSR_RXPKTRDY;
+			musb_writew(epio, MUSB_RXCSR, csr);
+		}
+
+		/* incomplete, and not short? wait for next IN packet */
+		if ((request->actual < request->length)
+				&& (musb_ep->dma->actual_len
+					== musb_ep->packet_sz)) {
+			/* In double buffer case, continue to unload fifo if
+ 			 * there is Rx packet in FIFO.
+ 			 **/
+			csr = musb_readw(epio, MUSB_RXCSR);
+			if ((csr & MUSB_RXCSR_RXPKTRDY) &&
+				hw_ep->rx_double_buffered)
+				goto exit;
+			return;
+		}
+#endif
+		musb_g_giveback(musb_ep, request, 0);
+		/*
+		 * In the giveback function the MUSB lock is
+		 * released and acquired after sometime. During
+		 * this time period the INDEX register could get
+		 * changed by the gadget_queue function especially
+		 * on SMP systems. Reselect the INDEX to be sure
+		 * we are reading/modifying the right registers
+		 */
+		musb_ep_select(mbase, epnum);
+
+		req = next_request(musb_ep);
+		if (!req)
+			return;
+	}
+#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
+	defined(CONFIG_USB_UX500_DMA)
+exit:
+#endif
+	/* 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;
+	void __iomem		*regs;
+	struct musb		*musb;
+	void __iomem	*mbase;
+	u8		epnum;
+	u16		csr;
+	unsigned	tmp;
+	int		status = -EINVAL;
+
+	if (!ep || !desc)
+		return -EINVAL;
+
+	musb_ep = to_musb_ep(ep);
+	hw_ep = musb_ep->hw_ep;
+	regs = hw_ep->regs;
+	musb = musb_ep->musb;
+	mbase = musb->mregs;
+	epnum = musb_ep->current_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 */
+	tmp = usb_endpoint_maxp_mult(desc) - 1;
+	if (tmp) {
+		int ok;
+
+		if (usb_endpoint_dir_in(desc))
+			ok = musb->hb_iso_tx;
+		else
+			ok = musb->hb_iso_rx;
+
+		if (!ok) {
+			musb_dbg(musb, "no support for high bandwidth ISO");
+			goto fail;
+		}
+		musb_ep->hb_mult = tmp;
+	} else {
+		musb_ep->hb_mult = 0;
+	}
+
+	musb_ep->packet_sz = usb_endpoint_maxp(desc);
+	tmp = musb_ep->packet_sz * (musb_ep->hb_mult + 1);
+
+	/* enable the interrupts for the endpoint, set the endpoint
+	 * packet size (or fail), set the mode, clear the fifo
+	 */
+	musb_ep_select(mbase, epnum);
+	if (usb_endpoint_dir_in(desc)) {
+
+		if (hw_ep->is_shared_fifo)
+			musb_ep->is_in = 1;
+		if (!musb_ep->is_in)
+			goto fail;
+
+		if (tmp > hw_ep->max_packet_sz_tx) {
+			musb_dbg(musb, "packet size beyond hardware FIFO size");
+			goto fail;
+		}
+
+		musb->intrtxe |= (1 << epnum);
+		musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
+
+		/* REVISIT if can_bulk_split(), use by updating "tmp";
+		 * likewise high bandwidth periodic tx
+		 */
+		/* Set TXMAXP with the FIFO size of the endpoint
+		 * to disable double buffering mode.
+		 */
+		if (can_bulk_split(musb, musb_ep->type))
+			musb_ep->hb_mult = (hw_ep->max_packet_sz_tx /
+						musb_ep->packet_sz) - 1;
+		musb_writew(regs, MUSB_TXMAXP, musb_ep->packet_sz
+				| (musb_ep->hb_mult << 11));
+
+		csr = MUSB_TXCSR_MODE | MUSB_TXCSR_CLRDATATOG;
+		if (musb_readw(regs, MUSB_TXCSR)
+				& MUSB_TXCSR_FIFONOTEMPTY)
+			csr |= MUSB_TXCSR_FLUSHFIFO;
+		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
+			csr |= MUSB_TXCSR_P_ISO;
+
+		/* set twice in case of double buffering */
+		musb_writew(regs, MUSB_TXCSR, csr);
+		/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
+		musb_writew(regs, MUSB_TXCSR, csr);
+
+	} else {
+
+		if (hw_ep->is_shared_fifo)
+			musb_ep->is_in = 0;
+		if (musb_ep->is_in)
+			goto fail;
+
+		if (tmp > hw_ep->max_packet_sz_rx) {
+			musb_dbg(musb, "packet size beyond hardware FIFO size");
+			goto fail;
+		}
+
+		musb->intrrxe |= (1 << epnum);
+		musb_writew(mbase, MUSB_INTRRXE, musb->intrrxe);
+
+		/* REVISIT if can_bulk_combine() use by updating "tmp"
+		 * likewise high bandwidth periodic rx
+		 */
+		/* Set RXMAXP with the FIFO size of the endpoint
+		 * to disable double buffering mode.
+		 */
+		musb_writew(regs, MUSB_RXMAXP, musb_ep->packet_sz
+				| (musb_ep->hb_mult << 11));
+
+		/* force shared fifo to OUT-only mode */
+		if (hw_ep->is_shared_fifo) {
+			csr = musb_readw(regs, MUSB_TXCSR);
+			csr &= ~(MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY);
+			musb_writew(regs, MUSB_TXCSR, csr);
+		}
+
+		csr = MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_CLRDATATOG;
+		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
+			csr |= MUSB_RXCSR_P_ISO;
+		else if (musb_ep->type == USB_ENDPOINT_XFER_INT)
+			csr |= MUSB_RXCSR_DISNYET;
+
+		/* set twice in case of double buffering */
+		musb_writew(regs, MUSB_RXCSR, csr);
+		musb_writew(regs, MUSB_RXCSR, csr);
+	}
+
+	/* 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;
+
+	pr_debug("%s periph: enabled %s for %s %s, %smaxpacket %d\n",
+			musb_driver_name, musb_ep->end_point.name,
+			musb_ep_xfertype_string(musb_ep->type),
+			musb_ep->is_in ? "IN" : "OUT",
+			musb_ep->dma ? "dma, " : "",
+			musb_ep->packet_sz);
+
+	schedule_delayed_work(&musb->irq_work, 0);
+
+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)
+{
+	unsigned long	flags;
+	struct musb	*musb;
+	u8		epnum;
+	struct musb_ep	*musb_ep;
+	void __iomem	*epio;
+
+	musb_ep = to_musb_ep(ep);
+	musb = musb_ep->musb;
+	epnum = musb_ep->current_epnum;
+	epio = musb->endpoints[epnum].regs;
+
+	spin_lock_irqsave(&musb->lock, flags);
+	musb_ep_select(musb->mregs, epnum);
+
+	/* zero the endpoint sizes */
+	if (musb_ep->is_in) {
+		musb->intrtxe &= ~(1 << epnum);
+		musb_writew(musb->mregs, MUSB_INTRTXE, musb->intrtxe);
+		musb_writew(epio, MUSB_TXMAXP, 0);
+	} else {
+		musb->intrrxe &= ~(1 << epnum);
+		musb_writew(musb->mregs, MUSB_INTRRXE, musb->intrrxe);
+		musb_writew(epio, MUSB_RXMAXP, 0);
+	}
+
+	/* abort all pending DMA and requests */
+	nuke(musb_ep, -ESHUTDOWN);
+
+	musb_ep->desc = NULL;
+	musb_ep->end_point.desc = NULL;
+
+	schedule_delayed_work(&musb->irq_work, 0);
+
+	spin_unlock_irqrestore(&(musb->lock), flags);
+
+	musb_dbg(musb, "%s", musb_ep->end_point.name);
+
+	return 0;
+}
+
+/*
+ * 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;
+
+	trace_musb_req_alloc(request);
+	return &request->request;
+}
+
+/*
+ * Free a request
+ * Reused by ep0 code.
+ */
+void musb_free_request(struct usb_ep *ep, struct usb_request *req)
+{
+	struct musb_request *request = to_musb_request(req);
+
+	trace_musb_req_free(request);
+	kfree(request);
+}
+
+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)
+{
+	trace_musb_req_start(req);
+	musb_ep_select(musb->mregs, req->epnum);
+	if (req->tx)
+		txstate(musb, req);
+	else
+		rxstate(musb, req);
+}
+
+static int musb_ep_restart_resume_work(struct musb *musb, void *data)
+{
+	struct musb_request *req = data;
+
+	musb_ep_restart(musb, req);
+
+	return 0;
+}
+
+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;
+	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;
+
+	status = pm_runtime_get(musb->controller);
+	if ((status != -EINPROGRESS) && status < 0) {
+		dev_err(musb->controller,
+			"pm runtime get failed in %s\n",
+			__func__);
+		pm_runtime_put_noidle(musb->controller);
+
+		return status;
+	}
+	status = 0;
+
+	trace_musb_req_enq(request);
+
+	/* 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) {
+		musb_dbg(musb, "req %p queued to %s while ep %s",
+				req, ep->name, "disabled");
+		status = -ESHUTDOWN;
+		unmap_dma_buffer(request, musb);
+		goto unlock;
+	}
+
+	/* add request to the list */
+	list_add_tail(&request->list, &musb_ep->req_list);
+
+	/* it this is the head of the queue, start i/o ... */
+	if (!musb_ep->busy && &request->list == musb_ep->req_list.next) {
+		status = musb_queue_resume_work(musb,
+						musb_ep_restart_resume_work,
+						request);
+		if (status < 0) {
+			dev_err(musb->controller, "%s resume work: %i\n",
+				__func__, status);
+			list_del(&request->list);
+		}
+	}
+
+unlock:
+	spin_unlock_irqrestore(&musb->lock, lockflags);
+	pm_runtime_mark_last_busy(musb->controller);
+	pm_runtime_put_autosuspend(musb->controller);
+
+	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 || req->ep != musb_ep)
+		return -EINVAL;
+
+	trace_musb_req_deq(req);
+
+	spin_lock_irqsave(&musb->lock, flags);
+
+	list_for_each_entry(r, &musb_ep->req_list, list) {
+		if (r == req)
+			break;
+	}
+	if (r != req) {
+		dev_err(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 ... */
+	else if (is_dma_capable() && musb_ep->dma) {
+		struct dma_controller	*c = musb->dma_controller;
+
+		musb_ep_select(musb->mregs, musb_ep->current_epnum);
+		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);
+	}
+
+done:
+	spin_unlock_irqrestore(&musb->lock, flags);
+	return status;
+}
+
+/*
+ * Set or clear the halt bit of an endpoint. A halted endpoint 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;
+	void __iomem		*epio = musb->endpoints[epnum].regs;
+	void __iomem		*mbase;
+	unsigned long		flags;
+	u16			csr;
+	struct musb_request	*request;
+	int			status = 0;
+
+	if (!ep)
+		return -EINVAL;
+	mbase = musb->mregs;
+
+	spin_lock_irqsave(&musb->lock, flags);
+
+	if ((USB_ENDPOINT_XFER_ISOC == musb_ep->type)) {
+		status = -EINVAL;
+		goto done;
+	}
+
+	musb_ep_select(mbase, epnum);
+
+	request = next_request(musb_ep);
+	if (value) {
+		if (request) {
+			musb_dbg(musb, "request in progress, cannot halt %s",
+			    ep->name);
+			status = -EAGAIN;
+			goto done;
+		}
+		/* Cannot portably stall with non-empty FIFO */
+		if (musb_ep->is_in) {
+			csr = musb_readw(epio, MUSB_TXCSR);
+			if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
+				musb_dbg(musb, "FIFO busy, cannot halt %s",
+						ep->name);
+				status = -EAGAIN;
+				goto done;
+			}
+		}
+	} else
+		musb_ep->wedged = 0;
+
+	/* set/clear the stall and toggle bits */
+	musb_dbg(musb, "%s: %s stall", ep->name, value ? "set" : "clear");
+	if (musb_ep->is_in) {
+		csr = musb_readw(epio, MUSB_TXCSR);
+		csr |= MUSB_TXCSR_P_WZC_BITS
+			| MUSB_TXCSR_CLRDATATOG;
+		if (value)
+			csr |= MUSB_TXCSR_P_SENDSTALL;
+		else
+			csr &= ~(MUSB_TXCSR_P_SENDSTALL
+				| MUSB_TXCSR_P_SENTSTALL);
+		csr &= ~MUSB_TXCSR_TXPKTRDY;
+		musb_writew(epio, MUSB_TXCSR, csr);
+	} else {
+		csr = musb_readw(epio, MUSB_RXCSR);
+		csr |= MUSB_RXCSR_P_WZC_BITS
+			| MUSB_RXCSR_FLUSHFIFO
+			| MUSB_RXCSR_CLRDATATOG;
+		if (value)
+			csr |= MUSB_RXCSR_P_SENDSTALL;
+		else
+			csr &= ~(MUSB_RXCSR_P_SENDSTALL
+				| MUSB_RXCSR_P_SENTSTALL);
+		musb_writew(epio, MUSB_RXCSR, csr);
+	}
+
+	/* maybe start the first request in the queue */
+	if (!musb_ep->busy && !value && request) {
+		musb_dbg(musb, "restarting the request");
+		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);
+	void __iomem		*epio = musb_ep->hw_ep->regs;
+	int			retval = -EINVAL;
+
+	if (musb_ep->desc && !musb_ep->is_in) {
+		struct musb		*musb = musb_ep->musb;
+		int			epnum = musb_ep->current_epnum;
+		void __iomem		*mbase = musb->mregs;
+		unsigned long		flags;
+
+		spin_lock_irqsave(&musb->lock, flags);
+
+		musb_ep_select(mbase, epnum);
+		/* FIXME return zero unless RXPKTRDY is set */
+		retval = musb_readw(epio, MUSB_RXCOUNT);
+
+		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	*epio = musb->endpoints[epnum].regs;
+	void __iomem	*mbase;
+	unsigned long	flags;
+	u16		csr;
+
+	mbase = musb->mregs;
+
+	spin_lock_irqsave(&musb->lock, flags);
+	musb_ep_select(mbase, (u8) epnum);
+
+	/* disable interrupts */
+	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe & ~(1 << epnum));
+
+	if (musb_ep->is_in) {
+		csr = musb_readw(epio, MUSB_TXCSR);
+		if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
+			csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_P_WZC_BITS;
+			/*
+			 * Setting both TXPKTRDY and FLUSHFIFO makes controller
+			 * to interrupt current FIFO loading, but not flushing
+			 * the already loaded ones.
+			 */
+			csr &= ~MUSB_TXCSR_TXPKTRDY;
+			musb_writew(epio, MUSB_TXCSR, csr);
+			/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
+			musb_writew(epio, MUSB_TXCSR, csr);
+		}
+	} else {
+		csr = musb_readw(epio, MUSB_RXCSR);
+		csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_P_WZC_BITS;
+		musb_writew(epio, MUSB_RXCSR, csr);
+		musb_writew(epio, MUSB_RXCSR, csr);
+	}
+
+	/* re-enable interrupt */
+	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
+	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)musb_readw(musb->mregs, MUSB_FRAME);
+}
+
+static int musb_gadget_wakeup(struct usb_gadget *gadget)
+{
+	struct musb	*musb = gadget_to_musb(gadget);
+	void __iomem	*mregs = musb->mregs;
+	unsigned long	flags;
+	int		status = -EINVAL;
+	u8		power, devctl;
+	int		retries;
+
+	spin_lock_irqsave(&musb->lock, flags);
+
+	switch (musb->xceiv->otg->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. */
+		devctl = musb_readb(mregs, MUSB_DEVCTL);
+		musb_dbg(musb, "Sending SRP: devctl: %02x", devctl);
+		devctl |= MUSB_DEVCTL_SESSION;
+		musb_writeb(mregs, MUSB_DEVCTL, devctl);
+		devctl = musb_readb(mregs, MUSB_DEVCTL);
+		retries = 100;
+		while (!(devctl & MUSB_DEVCTL_SESSION)) {
+			devctl = musb_readb(mregs, MUSB_DEVCTL);
+			if (retries-- < 1)
+				break;
+		}
+		retries = 10000;
+		while (devctl & MUSB_DEVCTL_SESSION) {
+			devctl = musb_readb(mregs, MUSB_DEVCTL);
+			if (retries-- < 1)
+				break;
+		}
+
+		spin_unlock_irqrestore(&musb->lock, flags);
+		otg_start_srp(musb->xceiv->otg);
+		spin_lock_irqsave(&musb->lock, flags);
+
+		/* Block idling for at least 1s */
+		musb_platform_try_idle(musb,
+			jiffies + msecs_to_jiffies(1 * HZ));
+
+		status = 0;
+		goto done;
+	default:
+		musb_dbg(musb, "Unhandled wake: %s",
+			usb_otg_state_string(musb->xceiv->otg->state));
+		goto done;
+	}
+
+	status = 0;
+
+	power = musb_readb(mregs, MUSB_POWER);
+	power |= MUSB_POWER_RESUME;
+	musb_writeb(mregs, MUSB_POWER, power);
+	musb_dbg(musb, "issue wakeup");
+
+	/* FIXME do this next chunk in a timer callback, no udelay */
+	mdelay(2);
+
+	power = musb_readb(mregs, MUSB_POWER);
+	power &= ~MUSB_POWER_RESUME;
+	musb_writeb(mregs, MUSB_POWER, power);
+done:
+	spin_unlock_irqrestore(&musb->lock, flags);
+	return status;
+}
+
+static int
+musb_gadget_set_self_powered(struct usb_gadget *gadget, int is_selfpowered)
+{
+	gadget->is_selfpowered = !!is_selfpowered;
+	return 0;
+}
+
+static void musb_pullup(struct musb *musb, int is_on)
+{
+	u8 power;
+
+	power = musb_readb(musb->mregs, MUSB_POWER);
+	if (is_on)
+		power |= MUSB_POWER_SOFTCONN;
+	else
+		power &= ~MUSB_POWER_SOFTCONN;
+
+	/* FIXME if on, HdrcStart; if off, HdrcStop */
+
+	musb_dbg(musb, "gadget D+ pullup %s",
+		is_on ? "on" : "off");
+	musb_writeb(musb->mregs, MUSB_POWER, power);
+}
+
+#if 0
+static int musb_gadget_vbus_session(struct usb_gadget *gadget, int is_active)
+{
+	musb_dbg(musb, "<= %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);
+
+	return usb_phy_set_power(musb->xceiv, mA);
+}
+
+static void musb_gadget_work(struct work_struct *work)
+{
+	struct musb *musb;
+	unsigned long flags;
+
+	musb = container_of(work, struct musb, gadget_work.work);
+	pm_runtime_get_sync(musb->controller);
+	spin_lock_irqsave(&musb->lock, flags);
+	musb_pullup(musb, musb->softconnect);
+	spin_unlock_irqrestore(&musb->lock, flags);
+	pm_runtime_mark_last_busy(musb->controller);
+	pm_runtime_put_autosuspend(musb->controller);
+}
+
+static int musb_gadget_pullup(struct usb_gadget *gadget, int is_on)
+{
+	struct musb	*musb = gadget_to_musb(gadget);
+	unsigned long	flags;
+
+	is_on = !!is_on;
+
+	/* 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;
+		schedule_delayed_work(&musb->gadget_work, 0);
+	}
+	spin_unlock_irqrestore(&musb->lock, flags);
+
+	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);
+
+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,
+};
+
+/* ----------------------------------------------------------------------- */
+
+/* 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...
+ */
+
+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"));
+	ep->end_point.name = ep->name;
+	INIT_LIST_HEAD(&ep->end_point.ep_list);
+	if (!epnum) {
+		usb_ep_set_maxpacket_limit(&ep->end_point, 64);
+		ep->end_point.caps.type_control = true;
+		ep->end_point.ops = &musb_g_ep0_ops;
+		musb->g.ep0 = &ep->end_point;
+	} else {
+		if (is_in)
+			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_tx);
+		else
+			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_rx);
+		ep->end_point.caps.type_iso = true;
+		ep->end_point.caps.type_bulk = true;
+		ep->end_point.caps.type_int = true;
+		ep->end_point.ops = &musb_ep_ops;
+		list_add_tail(&ep->end_point.ep_list, &musb->g.ep_list);
+	}
+
+	if (!epnum || hw_ep->is_shared_fifo) {
+		ep->end_point.caps.dir_in = true;
+		ep->end_point.caps.dir_out = true;
+	} else if (is_in)
+		ep->end_point.caps.dir_in = true;
+	else
+		ep->end_point.caps.dir_out = true;
+}
+
+/*
+ * 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));
+
+	for (epnum = 0, hw_ep = musb->endpoints;
+			epnum < musb->nr_endpoints;
+			epnum++, hw_ep++) {
+		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_HIGH;
+	musb->g.speed = USB_SPEED_UNKNOWN;
+
+	MUSB_DEV_MODE(musb);
+	musb->xceiv->otg->state = OTG_STATE_B_IDLE;
+
+	/* this "gadget" abstracts/virtualizes the controller */
+	musb->g.name = musb_driver_name;
+	/* don't support otg protocols */
+	musb->g.is_otg = 0;
+	INIT_DELAYED_WORK(&musb->gadget_work, musb_gadget_work);
+	musb_g_init_endpoints(musb);
+
+	musb->is_active = 0;
+	musb_platform_try_idle(musb, 0);
+
+	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)
+{
+	if (musb->port_mode == MUSB_HOST)
+		return;
+
+	cancel_delayed_work_sync(&musb->gadget_work);
+	usb_del_gadget_udc(&musb->g);
+}
+
+/*
+ * 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;
+
+	if (driver->max_speed < USB_SPEED_HIGH) {
+		retval = -EINVAL;
+		goto err;
+	}
+
+	pm_runtime_get_sync(musb->controller);
+
+	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->otg->state = OTG_STATE_B_IDLE;
+	spin_unlock_irqrestore(&musb->lock, flags);
+
+	musb_start(musb);
+
+	/* REVISIT:  funcall to other code, which also
+	 * handles power budgeting ... this way also
+	 * ensures HdrcStart is indirectly called.
+	 */
+	if (musb->xceiv->last_event == USB_EVENT_ID)
+		musb_platform_set_vbus(musb, 1);
+
+	pm_runtime_mark_last_busy(musb->controller);
+	pm_runtime_put_autosuspend(musb->controller);
+
+	return 0;
+
+err:
+	return retval;
+}
+
+/*
+ * 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 musb	*musb = gadget_to_musb(g);
+	unsigned long	flags;
+
+	pm_runtime_get_sync(musb->controller);
+
+	/*
+	 * 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);
+
+	(void) musb_gadget_vbus_draw(&musb->g, 0);
+
+	musb->xceiv->otg->state = OTG_STATE_UNDEFINED;
+	musb_stop(musb);
+	otg_set_peripheral(musb->xceiv->otg, NULL);
+
+	musb->is_active = 0;
+	musb->gadget_driver = NULL;
+	musb_platform_try_idle(musb, 0);
+	spin_unlock_irqrestore(&musb->lock, flags);
+
+	/*
+	 * FIXME we need to be able to register another
+	 * gadget driver here and have everything work;
+	 * that currently misbehaves.
+	 */
+
+	/* Force check of devctl register for PM runtime */
+	schedule_delayed_work(&musb->irq_work, 0);
+
+	pm_runtime_mark_last_busy(musb->controller);
+	pm_runtime_put_autosuspend(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->otg->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:
+		WARNING("unhandled RESUME transition (%s)\n",
+				usb_otg_state_string(musb->xceiv->otg->state));
+	}
+}
+
+/* called when SOF packets stop for 3+ msec */
+void musb_g_suspend(struct musb *musb)
+{
+	u8	devctl;
+
+	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
+	musb_dbg(musb, "musb_g_suspend: devctl %02x", devctl);
+
+	switch (musb->xceiv->otg->state) {
+	case OTG_STATE_B_IDLE:
+		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
+			musb->xceiv->otg->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);
+		}
+		break;
+	default:
+		/* REVISIT if B_HOST, clear DEVCTL.HOSTREQ;
+		 * A_PERIPHERAL may need care too
+		 */
+		WARNING("unhandled SUSPEND transition (%s)",
+				usb_otg_state_string(musb->xceiv->otg->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)
+{
+	void __iomem	*mregs = musb->mregs;
+	u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
+
+	musb_dbg(musb, "musb_g_disconnect: devctl %02x", devctl);
+
+	/* clear HR */
+	musb_writeb(mregs, MUSB_DEVCTL, devctl & MUSB_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->otg->state) {
+	default:
+		musb_dbg(musb, "Unhandled disconnect %s, setting a_idle",
+			usb_otg_state_string(musb->xceiv->otg->state));
+		musb->xceiv->otg->state = OTG_STATE_A_IDLE;
+		MUSB_HST_MODE(musb);
+		break;
+	case OTG_STATE_A_PERIPHERAL:
+		musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
+		MUSB_HST_MODE(musb);
+		break;
+	case OTG_STATE_B_WAIT_ACON:
+	case OTG_STATE_B_HOST:
+	case OTG_STATE_B_PERIPHERAL:
+	case OTG_STATE_B_IDLE:
+		musb->xceiv->otg->state = OTG_STATE_B_IDLE;
+		break;
+	case OTG_STATE_B_SRP_INIT:
+		break;
+	}
+
+	musb->is_active = 0;
+}
+
+void musb_g_reset(struct musb *musb)
+__releases(musb->lock)
+__acquires(musb->lock)
+{
+	void __iomem	*mbase = musb->mregs;
+	u8		devctl = musb_readb(mbase, MUSB_DEVCTL);
+	u8		power;
+
+	musb_dbg(musb, "<== %s driver '%s'",
+			(devctl & MUSB_DEVCTL_BDEVICE)
+				? "B-Device" : "A-Device",
+			musb->gadget_driver
+				? musb->gadget_driver->driver.name
+				: NULL
+			);
+
+	/* report reset, if we didn't already (flushing EP state) */
+	if (musb->gadget_driver && musb->g.speed != USB_SPEED_UNKNOWN) {
+		spin_unlock(&musb->lock);
+		usb_gadget_udc_reset(&musb->g, musb->gadget_driver);
+		spin_lock(&musb->lock);
+	}
+
+	/* clear HR */
+	else if (devctl & MUSB_DEVCTL_HR)
+		musb_writeb(mbase, MUSB_DEVCTL, MUSB_DEVCTL_SESSION);
+
+
+	/* what speed did we negotiate? */
+	power = musb_readb(mbase, MUSB_POWER);
+	musb->g.speed = (power & MUSB_POWER_HSMODE)
+			? USB_SPEED_HIGH : USB_SPEED_FULL;
+
+	/* 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;
+	musb->g.quirk_zlp_not_supp = 1;
+
+	/* Normal reset, as B-Device;
+	 * or else after HNP, as A-Device
+	 */
+	if (!musb->g.is_otg) {
+		/* USB device controllers that are not OTG compatible
+		 * may not have DEVCTL register in silicon.
+		 * In that case, do not rely on devctl for setting
+		 * peripheral mode.
+		 */
+		musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
+		musb->g.is_a_peripheral = 0;
+	} else if (devctl & MUSB_DEVCTL_BDEVICE) {
+		musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
+		musb->g.is_a_peripheral = 0;
+	} else {
+		musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
+		musb->g.is_a_peripheral = 1;
+	}
+
+	/* start with default limits on VBUS power draw */
+	(void) musb_gadget_vbus_draw(&musb->g, 8);
+}