Add qemu 2.4.0
[kvmfornfv.git] / qemu / roms / u-boot / drivers / usb / musb-new / musb_gadget.c
diff --git a/qemu/roms/u-boot/drivers/usb/musb-new/musb_gadget.c b/qemu/roms/u-boot/drivers/usb/musb-new/musb_gadget.c
new file mode 100644 (file)
index 0000000..d2cb91a
--- /dev/null
@@ -0,0 +1,2333 @@
+/*
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ * 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.
+ *
+ */
+
+#define __UBOOT__
+#ifndef __UBOOT__
+#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>
+#else
+#include <common.h>
+#include <linux/usb/ch9.h>
+#include "linux-compat.h"
+#endif
+
+#include "musb_core.h"
+
+
+/* MUSB PERIPHERAL status 3-mar-2006:
+ *
+ * - EP0 seems solid.  It passes both USBCV and usbtest control cases.
+ *   Minor glitches:
+ *
+ *     + remote wakeup to Linux hosts work, but saw USBCV failures;
+ *       in one test run (operator error?)
+ *     + endpoint halt tests -- in both usbtest and usbcv -- seem
+ *       to break when dma is enabled ... is something wrongly
+ *       clearing SENDSTALL?
+ *
+ * - Mass storage behaved ok when last tested.  Network traffic patterns
+ *   (with lots of short transfers etc) need retesting; they turn up the
+ *   worst cases of the DMA, since short packets are typical but are not
+ *   required.
+ *
+ * - TX/IN
+ *     + both pio and dma behave in with network and g_zero tests
+ *     + no cppi throughput issues other than no-hw-queueing
+ *     + failed with FLAT_REG (DaVinci)
+ *     + seems to behave with double buffering, PIO -and- CPPI
+ *     + with gadgetfs + AIO, requests got lost?
+ *
+ * - RX/OUT
+ *     + both pio and dma behave in with network and g_zero tests
+ *     + dma is slow in typical case (short_not_ok is clear)
+ *     + double buffering ok with PIO
+ *     + double buffering *FAILS* with CPPI, wrong data bytes sometimes
+ *     + request lossage observed with gadgetfs
+ *
+ * - ISO not tested ... might work, but only weakly isochronous
+ *
+ * - Gadget driver disabling of softconnect during bind() is ignored; so
+ *   drivers can't hold off host requests until userspace is ready.
+ *   (Workaround:  they can turn it off later.)
+ *
+ * - PORTABILITY (assumes PIO works):
+ *     + DaVinci, basically works with cppi dma
+ *     + OMAP 2430, ditto with mentor dma
+ *     + TUSB 6010, platform-specific dma in the works
+ */
+
+/* ----------------------------------------------------------------------- */
+
+#define is_buffer_mapped(req) (is_dma_capable() && \
+                                       (req->map_state != UN_MAPPED))
+
+#ifndef CONFIG_MUSB_PIO_ONLY
+/* 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) {
+               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;
+       } 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)
+{
+       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) {
+               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;
+}
+#else
+static inline void map_dma_buffer(struct musb_request *request,
+                       struct musb *musb, struct musb_ep *musb_ep)
+{
+}
+
+static inline void unmap_dma_buffer(struct musb_request *request,
+                               struct musb *musb)
+{
+}
+#endif
+
+/*
+ * 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);
+       unmap_dma_buffer(req, musb);
+       if (request->status == 0)
+               dev_dbg(musb->controller, "%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",
+                               ep->end_point.name, request,
+                               req->request.actual, req->request.length,
+                               request->status);
+       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             *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);
+               dev_dbg(musb->controller, "%s: abort DMA --> %d\n",
+                               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;
+}
+
+
+#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
+
+/*
+ * 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) {
+               dev_dbg(musb->controller, "ep:%s disabled - ignore request\n",
+                                               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) {
+               dev_dbg(musb->controller, "dma pending...\n");
+               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) {
+               dev_dbg(musb->controller, "%s old packet still ready , txcsr %03x\n",
+                               musb_ep->end_point.name, csr);
+               return;
+       }
+
+       if (csr & MUSB_TXCSR_P_SENDSTALL) {
+               dev_dbg(musb->controller, "%s stalling, txcsr %03x\n",
+                               musb_ep->end_point.name, csr);
+               return;
+       }
+
+       dev_dbg(musb->controller, "hw_ep%d, maxpacket %d, fifo count %d, txcsr %03x\n",
+                       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);
+
+               /* MUSB_TXCSR_P_ISO is still set correctly */
+
+#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA)
+               {
+                       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);
+                                       if (!musb_ep->hb_mult)
+                                               csr |= MUSB_TXCSR_AUTOSET;
+                               }
+                               csr &= ~MUSB_TXCSR_P_UNDERRUN;
+
+                               musb_writew(epio, MUSB_TXCSR, csr);
+                       }
+               }
+
+#elif defined(CONFIG_USB_TI_CPPI_DMA)
+               /* 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 */
+               }
+#elif defined(CONFIG_USB_TUSB_OMAP_DMA)
+               use_dma = use_dma && c->channel_program(
+                               musb_ep->dma, musb_ep->packet_sz,
+                               request->zero,
+                               request->dma + request->actual,
+                               request_size);
+#endif
+       }
+#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... */
+       dev_dbg(musb->controller, "%s TX/IN %s len %d/%d, txcsr %04x, fifo %d/%d\n",
+                       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);
+       dev_dbg(musb->controller, "<== %s, txcsr %04x\n", 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?
+                */
+               dev_dbg(musb->controller, "%s dma still busy?\n", musb_ep->end_point.name);
+               return;
+       }
+
+       if (request) {
+               u8      is_dma = 0;
+
+               if (dma && (csr & MUSB_TXCSR_DMAENAB)) {
+                       is_dma = 1;
+                       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;
+                       dev_dbg(musb->controller, "TXCSR%d %04x, DMA off, len %zu, req %p\n",
+                               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))
+#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA)
+                       || (is_dma && (!dma->desired_mode ||
+                               (request->actual &
+                                       (musb_ep->packet_sz - 1))))
+#endif
+               ) {
+                       /*
+                        * On DMA completion, FIFO may not be
+                        * available yet...
+                        */
+                       if (csr & MUSB_TXCSR_TXPKTRDY)
+                               return;
+
+                       dev_dbg(musb->controller, "sending zero pkt\n");
+                       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) {
+                               dev_dbg(musb->controller, "%s idle now\n",
+                                       musb_ep->end_point.name);
+                               return;
+                       }
+               }
+
+               txstate(musb, req);
+       }
+}
+
+/* ------------------------------------------------------------ */
+
+#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;
+       void __iomem            *epio = musb->endpoints[epnum].regs;
+       unsigned                fifo_count = 0;
+       u16                     len;
+       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;
+
+       len = musb_ep->packet_sz;
+
+       /* Check if EP is disabled */
+       if (!musb_ep->desc) {
+               dev_dbg(musb->controller, "ep:%s disabled - ignore request\n",
+                                               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) {
+               dev_dbg(musb->controller, "DMA pending...\n");
+               return;
+       }
+
+       if (csr & MUSB_RXCSR_P_SENDSTALL) {
+               dev_dbg(musb->controller, "%s stalling, RXCSR %04x\n",
+                   musb_ep->end_point.name, csr);
+               return;
+       }
+
+       if (is_cppi_enabled() && 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) {
+               len = 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 && len == musb_ep->packet_sz)
+                       use_mode_1 = 1;
+               else
+                       use_mode_1 = 0;
+
+               if (request->actual < request->length) {
+#ifdef CONFIG_USB_INVENTRA_DMA
+                       if (is_buffer_mapped(req)) {
+                               struct dma_controller   *c;
+                               struct dma_channel      *channel;
+                               int                     use_dma = 0;
+
+                               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);
+
+                               } 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);
+                               }
+
+                               if (request->actual < request->length) {
+                                       int transfer_size = 0;
+                                       if (use_mode_1) {
+                                               transfer_size = min(request->length - request->actual,
+                                                               channel->max_len);
+                                               musb_ep->dma->desired_mode = 1;
+                                       } else {
+                                               transfer_size = min(request->length - request->actual,
+                                                               (unsigned)len);
+                                               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;
+                       }
+#elif defined(CONFIG_USB_UX500_DMA)
+                       if ((is_buffer_mapped(req)) &&
+                               (request->actual < request->length)) {
+
+                               struct dma_controller *c;
+                               struct dma_channel *channel;
+                               int transfer_size = 0;
+
+                               c = musb->dma_controller;
+                               channel = musb_ep->dma;
+
+                               /* In case first packet is short */
+                               if (len < musb_ep->packet_sz)
+                                       transfer_size = len;
+                               else if (request->short_not_ok)
+                                       transfer_size = min(request->length -
+                                                       request->actual,
+                                                       channel->max_len);
+                               else
+                                       transfer_size = min(request->length -
+                                                       request->actual,
+                                                       (unsigned)len);
+
+                               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;
+                       }
+#endif /* Mentor's DMA */
+
+                       fifo_count = request->length - request->actual;
+                       dev_dbg(musb->controller, "%s OUT/RX pio fifo %d/%d, maxpacket %d\n",
+                                       musb_ep->end_point.name,
+                                       len, fifo_count,
+                                       musb_ep->packet_sz);
+
+                       fifo_count = min_t(unsigned, len, fifo_count);
+
+#ifdef CONFIG_USB_TUSB_OMAP_DMA
+                       if (tusb_dma_omap() && is_buffer_mapped(req)) {
+                               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;
+                       }
+#endif
+                       /*
+                        * Unmap the dma buffer back to cpu if dma channel
+                        * programming fails. This buffer is mapped if the
+                        * channel allocation is successful
+                        */
+                        if (is_buffer_mapped(req)) {
+                               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);
+                       }
+
+                       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 || len < 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;
+
+       request = &req->request;
+
+       csr = musb_readw(epio, MUSB_RXCSR);
+       dma = is_dma_capable() ? musb_ep->dma : NULL;
+
+       dev_dbg(musb->controller, "<== %s, rxcsr %04x%s %p\n", 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);
+
+               dev_dbg(musb->controller, "%s iso overrun on %p\n", musb_ep->name, request);
+               if (request->status == -EINPROGRESS)
+                       request->status = -EOVERFLOW;
+       }
+       if (csr & MUSB_RXCSR_INCOMPRX) {
+               /* REVISIT not necessarily an error */
+               dev_dbg(musb->controller, "%s, incomprx\n", musb_ep->end_point.name);
+       }
+
+       if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
+               /* "should not happen"; likely RXPKTRDY pending for DMA */
+               dev_dbg(musb->controller, "%s busy, csr %04x\n",
+                       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;
+
+               dev_dbg(musb->controller, "RXCSR%d %04x, dma off, %04x, len %zu, req %p\n",
+                       epnum, csr,
+                       musb_readw(epio, MUSB_RXCSR),
+                       musb_ep->dma->actual_len, request);
+
+#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(desc);
+       if (tmp & ~0x07ff) {
+               int ok;
+
+               if (usb_endpoint_dir_in(desc))
+                       ok = musb->hb_iso_tx;
+               else
+                       ok = musb->hb_iso_rx;
+
+               if (!ok) {
+                       dev_dbg(musb->controller, "no support for high bandwidth ISO\n");
+                       goto fail;
+               }
+               musb_ep->hb_mult = (tmp >> 11) & 3;
+       } else {
+               musb_ep->hb_mult = 0;
+       }
+
+       musb_ep->packet_sz = tmp & 0x7ff;
+       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)) {
+               u16 int_txe = musb_readw(mbase, MUSB_INTRTXE);
+
+               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) {
+                       dev_dbg(musb->controller, "packet size beyond hardware FIFO size\n");
+                       goto fail;
+               }
+
+               int_txe |= (1 << epnum);
+               musb_writew(mbase, MUSB_INTRTXE, int_txe);
+
+               /* 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 (musb->double_buffer_not_ok)
+                       musb_writew(regs, MUSB_TXMAXP, hw_ep->max_packet_sz_tx);
+               else
+                       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 {
+               u16 int_rxe = musb_readw(mbase, MUSB_INTRRXE);
+
+               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) {
+                       dev_dbg(musb->controller, "packet size beyond hardware FIFO size\n");
+                       goto fail;
+               }
+
+               int_rxe |= (1 << epnum);
+               musb_writew(mbase, MUSB_INTRRXE, int_rxe);
+
+               /* 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.
+                */
+               if (musb->double_buffer_not_ok)
+                       musb_writew(regs, MUSB_RXMAXP, hw_ep->max_packet_sz_tx);
+               else
+                       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,
+                       ({ char *s; switch (musb_ep->type) {
+                       case USB_ENDPOINT_XFER_BULK:    s = "bulk"; break;
+                       case USB_ENDPOINT_XFER_INT:     s = "int"; break;
+                       default:                        s = "iso"; break;
+                       }; s; }),
+                       musb_ep->is_in ? "IN" : "OUT",
+                       musb_ep->dma ? "dma, " : "",
+                       musb_ep->packet_sz);
+
+       schedule_work(&musb->irq_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)
+{
+       unsigned long   flags;
+       struct musb     *musb;
+       u8              epnum;
+       struct musb_ep  *musb_ep;
+       void __iomem    *epio;
+       int             status = 0;
+
+       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) {
+               u16 int_txe = musb_readw(musb->mregs, MUSB_INTRTXE);
+               int_txe &= ~(1 << epnum);
+               musb_writew(musb->mregs, MUSB_INTRTXE, int_txe);
+               musb_writew(epio, MUSB_TXMAXP, 0);
+       } else {
+               u16 int_rxe = musb_readw(musb->mregs, MUSB_INTRRXE);
+               int_rxe &= ~(1 << epnum);
+               musb_writew(musb->mregs, MUSB_INTRRXE, int_rxe);
+               musb_writew(epio, MUSB_RXMAXP, 0);
+       }
+
+       musb_ep->desc = NULL;
+#ifndef __UBOOT__
+       musb_ep->end_point.desc = NULL;
+#endif
+
+       /* abort all pending DMA and requests */
+       nuke(musb_ep, -ESHUTDOWN);
+
+       schedule_work(&musb->irq_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             *musb = musb_ep->musb;
+       struct musb_request     *request = NULL;
+
+       request = kzalloc(sizeof *request, gfp_flags);
+       if (!request) {
+               dev_dbg(musb->controller, "not enough memory\n");
+               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)
+{
+       dev_dbg(musb->controller, "<== %s request %p len %u on hw_ep%d\n",
+               req->tx ? "TX/IN" : "RX/OUT",
+               &req->request, req->request.length, req->epnum);
+
+       musb_ep_select(musb->mregs, req->epnum);
+       if (req->tx)
+               txstate(musb, req);
+       else
+               rxstate(musb, req);
+}
+
+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;
+
+       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);
+
+       /* it this is the head of the queue, start i/o ... */
+       if (!musb_ep->busy && &request->list == musb_ep->req_list.next)
+               musb_ep_restart(musb, request);
+
+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;
+
+       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 ... */
+       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 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;
+       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) {
+                       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) {
+                       csr = musb_readw(epio, MUSB_TXCSR);
+                       if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
+                               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) {
+               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) {
+               dev_dbg(musb->controller, "restarting the request\n");
+               musb_ep_restart(musb, request);
+       }
+
+done:
+       spin_unlock_irqrestore(&musb->lock, flags);
+       return status;
+}
+
+#ifndef __UBOOT__
+/*
+ * 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);
+}
+#endif
+
+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, int_txe;
+
+       mbase = musb->mregs;
+
+       spin_lock_irqsave(&musb->lock, flags);
+       musb_ep_select(mbase, (u8) epnum);
+
+       /* disable interrupts */
+       int_txe = musb_readw(mbase, MUSB_INTRTXE);
+       musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(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, int_txe);
+       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,
+#ifndef __UBOOT__
+       .set_wedge      = musb_gadget_set_wedge,
+#endif
+       .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)
+{
+#ifndef __UBOOT__
+       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->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);
+               dev_dbg(musb->controller, "Sending SRP: devctl: %02x\n", 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:
+               dev_dbg(musb->controller, "Unhandled wake: %s\n",
+                       otg_state_string(musb->xceiv->state));
+               goto done;
+       }
+
+       status = 0;
+
+       power = musb_readb(mregs, MUSB_POWER);
+       power |= MUSB_POWER_RESUME;
+       musb_writeb(mregs, MUSB_POWER, power);
+       dev_dbg(musb->controller, "issue wakeup\n");
+
+       /* 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;
+#else
+       return 0;
+#endif
+}
+
+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;
+}
+
+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 */
+
+       dev_dbg(musb->controller, "gadget D+ pullup %s\n",
+               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)
+{
+       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)
+{
+#ifndef __UBOOT__
+       struct musb     *musb = gadget_to_musb(gadget);
+
+       if (!musb->xceiv->set_power)
+               return -EOPNOTSUPP;
+       return usb_phy_set_power(musb->xceiv, mA);
+#else
+       return 0;
+#endif
+}
+
+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;
+
+       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_pullup(musb, is_on);
+       }
+       spin_unlock_irqrestore(&musb->lock, flags);
+
+       pm_runtime_put(musb->controller);
+
+       return 0;
+}
+
+#ifndef __UBOOT__
+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);
+#endif
+
+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,
+#ifndef __UBOOT__
+       .udc_start              = musb_gadget_start,
+       .udc_stop               = musb_gadget_stop,
+#endif
+};
+
+/* ----------------------------------------------------------------------- */
+
+/* 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...
+ */
+
+#ifndef __UBOOT__
+static void musb_gadget_release(struct device *dev)
+{
+       /* kref_put(WHAT) */
+       dev_dbg(dev, "%s\n", __func__);
+}
+#endif
+
+
+static void __devinit
+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) {
+               ep->end_point.maxpacket = 64;
+               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);
+       }
+}
+
+/*
+ * Initialize the endpoints exposed to peripheral drivers, with backlinks
+ * to the rest of the driver state.
+ */
+static inline void __devinit 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 __devinit 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;
+#ifndef __UBOOT__
+       musb->g.max_speed = USB_SPEED_HIGH;
+#endif
+       musb->g.speed = USB_SPEED_UNKNOWN;
+
+#ifndef __UBOOT__
+       /* 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;
+#endif
+       musb->g.name = musb_driver_name;
+
+#ifndef __UBOOT__
+       if (is_otg_enabled(musb))
+               musb->g.is_otg = 1;
+#endif
+
+       musb_g_init_endpoints(musb);
+
+       musb->is_active = 0;
+       musb_platform_try_idle(musb, 0);
+
+#ifndef __UBOOT__
+       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;
+#endif
+
+       return 0;
+#ifndef __UBOOT__
+err:
+       musb->g.dev.parent = NULL;
+       device_unregister(&musb->g.dev);
+       return status;
+#endif
+}
+
+void musb_gadget_cleanup(struct musb *musb)
+{
+#ifndef __UBOOT__
+       usb_del_gadget_udc(&musb->g);
+       if (musb->g.dev.parent)
+               device_unregister(&musb->g.dev);
+#endif
+}
+
+/*
+ * 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
+ */
+#ifndef __UBOOT__
+static int musb_gadget_start(struct usb_gadget *g,
+               struct usb_gadget_driver *driver)
+#else
+int musb_gadget_start(struct usb_gadget *g,
+               struct usb_gadget_driver *driver)
+#endif
+{
+       struct musb             *musb = gadget_to_musb(g);
+#ifndef __UBOOT__
+       struct usb_otg          *otg = musb->xceiv->otg;
+#endif
+       unsigned long           flags;
+       int                     retval = -EINVAL;
+
+#ifndef __UBOOT__
+       if (driver->max_speed < USB_SPEED_HIGH)
+               goto err0;
+#endif
+
+       pm_runtime_get_sync(musb->controller);
+
+#ifndef __UBOOT__
+       dev_dbg(musb->controller, "registering driver %s\n", driver->function);
+#endif
+
+       musb->softconnect = 0;
+       musb->gadget_driver = driver;
+
+       spin_lock_irqsave(&musb->lock, flags);
+       musb->is_active = 1;
+
+#ifndef __UBOOT__
+       otg_set_peripheral(otg, &musb->g);
+       musb->xceiv->state = OTG_STATE_B_IDLE;
+
+       /*
+        * FIXME this ignores the softconnect flag.  Drivers are
+        * allowed hold the peripheral inactive until for example
+        * userspace hooks up printer hardware or DSP codecs, so
+        * hosts only see fully functional devices.
+        */
+
+       if (!is_otg_enabled(musb))
+#endif
+               musb_start(musb);
+
+       spin_unlock_irqrestore(&musb->lock, flags);
+
+#ifndef __UBOOT__
+       if (is_otg_enabled(musb)) {
+               struct usb_hcd  *hcd = musb_to_hcd(musb);
+
+               dev_dbg(musb->controller, "OTG startup...\n");
+
+               /* REVISIT:  funcall to other code, which also
+                * handles power budgeting ... this way also
+                * ensures HdrcStart is indirectly called.
+                */
+               retval = usb_add_hcd(musb_to_hcd(musb), 0, 0);
+               if (retval < 0) {
+                       dev_dbg(musb->controller, "add_hcd failed, %d\n", retval);
+                       goto err2;
+               }
+
+               if ((musb->xceiv->last_event == USB_EVENT_ID)
+                                       && otg->set_vbus)
+                       otg_set_vbus(otg, 1);
+
+               hcd->self.uses_pio_for_control = 1;
+       }
+       if (musb->xceiv->last_event == USB_EVENT_NONE)
+               pm_runtime_put(musb->controller);
+#endif
+
+       return 0;
+
+#ifndef __UBOOT__
+err2:
+       if (!is_otg_enabled(musb))
+               musb_stop(musb);
+err0:
+       return retval;
+#endif
+}
+
+#ifndef __UBOOT__
+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_pullup(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++) {
+                       musb_ep_select(musb->mregs, i);
+                       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);
+
+       /*
+        * 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->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 (is_otg_enabled(musb)) {
+               usb_remove_hcd(musb_to_hcd(musb));
+               /* FIXME we need to be able to register another
+                * gadget driver here and have everything work;
+                * that currently misbehaves.
+                */
+       }
+
+       if (!is_otg_enabled(musb))
+               musb_stop(musb);
+
+       pm_runtime_put(musb->controller);
+
+       return 0;
+}
+#endif
+
+/* ----------------------------------------------------------------------- */
+
+/* lifecycle operations called through plat_uds.c */
+
+void musb_g_resume(struct musb *musb)
+{
+#ifndef __UBOOT__
+       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:
+               WARNING("unhandled RESUME transition (%s)\n",
+                               otg_state_string(musb->xceiv->state));
+       }
+#endif
+}
+
+/* called when SOF packets stop for 3+ msec */
+void musb_g_suspend(struct musb *musb)
+{
+#ifndef __UBOOT__
+       u8      devctl;
+
+       devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
+       dev_dbg(musb->controller, "devctl %02x\n", devctl);
+
+       switch (musb->xceiv->state) {
+       case OTG_STATE_B_IDLE:
+               if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
+                       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);
+               }
+               break;
+       default:
+               /* REVISIT if B_HOST, clear DEVCTL.HOSTREQ;
+                * A_PERIPHERAL may need care too
+                */
+               WARNING("unhandled SUSPEND transition (%s)\n",
+                               otg_state_string(musb->xceiv->state));
+       }
+#endif
+}
+
+/* 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);
+
+       dev_dbg(musb->controller, "devctl %02x\n", 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);
+       }
+
+#ifndef __UBOOT__
+       switch (musb->xceiv->state) {
+       default:
+               dev_dbg(musb->controller, "Unhandled disconnect %s, setting a_idle\n",
+                       otg_state_string(musb->xceiv->state));
+               musb->xceiv->state = OTG_STATE_A_IDLE;
+               MUSB_HST_MODE(musb);
+               break;
+       case OTG_STATE_A_PERIPHERAL:
+               musb->xceiv->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->state = OTG_STATE_B_IDLE;
+               break;
+       case OTG_STATE_B_SRP_INIT:
+               break;
+       }
+#endif
+
+       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;
+
+#ifndef __UBOOT__
+       dev_dbg(musb->controller, "<== %s addr=%x driver '%s'\n",
+                       (devctl & MUSB_DEVCTL_BDEVICE)
+                               ? "B-Device" : "A-Device",
+                       musb_readb(mbase, MUSB_FADDR),
+                       musb->gadget_driver
+                               ? musb->gadget_driver->driver.name
+                               : NULL
+                       );
+#endif
+
+       /* 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 & 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;
+
+#ifndef __UBOOT__
+       /* Normal reset, as B-Device;
+        * or else after HNP, as A-Device
+        */
+       if (devctl & MUSB_DEVCTL_BDEVICE) {
+               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);
+
+       /* start with default limits on VBUS power draw */
+       (void) musb_gadget_vbus_draw(&musb->g,
+                       is_otg_enabled(musb) ? 8 : 100);
+#endif
+}