diff options
Diffstat (limited to 'drivers/usb/musb/musb_gadget.c')
| -rw-r--r-- | drivers/usb/musb/musb_gadget.c | 2096 |
1 files changed, 2096 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..4c481cd66 --- /dev/null +++ b/drivers/usb/musb/musb_gadget.c @@ -0,0 +1,2096 @@ +/* + * 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. + * + */ + +#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" + + +/* ----------------------------------------------------------------------- */ + +#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); + + 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); + 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); + 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; +} + +/* + * 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 && request_size); + + /* 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); + /* + * 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 || + (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); + } + } + +#endif + if (is_cppi_enabled()) { + /* 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()) + 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... */ + 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); + } +} + +/* ------------------------------------------------------------ */ + +/* + * 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) { + 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) { + 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) { +#ifdef CONFIG_USB_INVENTRA_DMA + if (is_buffer_mapped(req)) { + 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; + } +#elif defined(CONFIG_USB_UX500_DMA) + if ((is_buffer_mapped(req)) && + (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; + } +#endif /* Mentor's DMA */ + + len = request->length - request->actual; + dev_dbg(musb->controller, "%s OUT/RX pio fifo %d/%d, maxpacket %d\n", + musb_ep->end_point.name, + fifo_count, len, + 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 || + 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; + + 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)) { + + 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; + } + + 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 (musb->double_buffer_not_ok) { + musb_writew(regs, MUSB_TXMAXP, hw_ep->max_packet_sz_tx); + } else { + 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) { + dev_dbg(musb->controller, "packet size beyond hardware FIFO size\n"); + 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. + */ + 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) { + 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); + } + + musb_ep->desc = NULL; + musb_ep->end_point.desc = NULL; + + /* 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; + 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) + musb_ep_restart(musb, request); + +unlock: + 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; +} + +/* + * 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); + 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", + 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); + 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; +} + +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 */ + + 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) +{ + struct musb *musb = gadget_to_musb(gadget); + + if (!musb->xceiv->set_power) + return -EOPNOTSUPP; + return usb_phy_set_power(musb->xceiv, mA); +} + +static int musb_gadget_pullup(struct usb_gadget *gadget, int is_on) +{ + struct musb *musb = gadget_to_musb(gadget); + unsigned long flags; + + 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; +} + +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.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.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 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->default_a = 0; + musb->xceiv->otg->state = OTG_STATE_B_IDLE; + + /* this "gadget" abstracts/virtualizes the controller */ + musb->g.name = musb_driver_name; +#if IS_ENABLED(CONFIG_USB_MUSB_DUAL_ROLE) + musb->g.is_otg = 1; +#elif IS_ENABLED(CONFIG_USB_MUSB_GADGET) + musb->g.is_otg = 0; +#endif + + 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_PORT_MODE_HOST) + return; + 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); + + if (musb->xceiv->last_event == USB_EVENT_NONE) + pm_runtime_put(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; + + 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->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. + */ + + pm_runtime_put(musb->controller); + + return 0; +} + +/* ----------------------------------------------------------------------- */ + +/* lifecycle operations called through plat_uds.c */ + +void musb_g_resume(struct musb *musb) +{ + musb->is_suspended = 0; + switch (musb->xceiv->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); + dev_dbg(musb->controller, "devctl %02x\n", 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)\n", + 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); + + 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); + } + + switch (musb->xceiv->otg->state) { + default: + dev_dbg(musb->controller, "Unhandled disconnect %s, setting a_idle\n", + 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; + + dev_dbg(musb->controller, "<== %s driver '%s'\n", + (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; + + /* 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); +} |