/* * at91_udc -- driver for at91-series USB peripheral controller * * Copyright (C) 2004 by Thomas Rathbone * Copyright (C) 2005 by HP Labs * Copyright (C) 2005 by David Brownell * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #undef DEBUG #undef VERBOSE #undef PACKET_TRACE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "at91_udc.h" /* * This controller is simple and PIO-only. It's used in many AT91-series * ARMv4T controllers, including the at91rm9200 (arm920T, with MMU), * at91sam9261 (arm926ejs, with MMU), and several no-mmu versions. * * This driver expects the board has been wired with two GPIOs suppporting * a VBUS sensing IRQ, and a D+ pullup. (They may be omitted, but the * testing hasn't covered such cases.) The pullup is most important; it * provides software control over whether the host enumerates the device. * The VBUS sensing helps during enumeration, and allows both USB clocks * (and the transceiver) to stay gated off until they're necessary, saving * power. During USB suspend, the 48 MHz clock is gated off. */ #define DRIVER_VERSION "8 March 2005" static const char driver_name [] = "at91_udc"; static const char ep0name[] = "ep0"; /*-------------------------------------------------------------------------*/ /* * Read from a UDP register. */ static inline unsigned long at91_udp_read(unsigned int reg) { void __iomem *udp_base = (void __iomem *)AT91_VA_BASE_UDP; return __raw_readl(udp_base + reg); } /* * Write to a UDP register. */ static inline void at91_udp_write(unsigned int reg, unsigned long value) { void __iomem *udp_base = (void __iomem *)AT91_VA_BASE_UDP; __raw_writel(value, udp_base + reg); } /*-------------------------------------------------------------------------*/ #ifdef CONFIG_USB_GADGET_DEBUG_FILES #include static const char debug_filename[] = "driver/udc"; #define FOURBITS "%s%s%s%s" #define EIGHTBITS FOURBITS FOURBITS static void proc_ep_show(struct seq_file *s, struct at91_ep *ep) { static char *types[] = { "control", "out-iso", "out-bulk", "out-int", "BOGUS", "in-iso", "in-bulk", "in-int"}; u32 csr; struct at91_request *req; unsigned long flags; local_irq_save(flags); csr = __raw_readl(ep->creg); /* NOTE: not collecting per-endpoint irq statistics... */ seq_printf(s, "\n"); seq_printf(s, "%s, maxpacket %d %s%s %s%s\n", ep->ep.name, ep->ep.maxpacket, ep->is_in ? "in" : "out", ep->is_iso ? " iso" : "", ep->is_pingpong ? (ep->fifo_bank ? "pong" : "ping") : "", ep->stopped ? " stopped" : ""); seq_printf(s, "csr %08x rxbytes=%d %s %s %s" EIGHTBITS "\n", csr, (csr & 0x07ff0000) >> 16, (csr & (1 << 15)) ? "enabled" : "disabled", (csr & (1 << 11)) ? "DATA1" : "DATA0", types[(csr & 0x700) >> 8], /* iff type is control then print current direction */ (!(csr & 0x700)) ? ((csr & (1 << 7)) ? " IN" : " OUT") : "", (csr & (1 << 6)) ? " rxdatabk1" : "", (csr & (1 << 5)) ? " forcestall" : "", (csr & (1 << 4)) ? " txpktrdy" : "", (csr & (1 << 3)) ? " stallsent" : "", (csr & (1 << 2)) ? " rxsetup" : "", (csr & (1 << 1)) ? " rxdatabk0" : "", (csr & (1 << 0)) ? " txcomp" : ""); if (list_empty (&ep->queue)) seq_printf(s, "\t(queue empty)\n"); else list_for_each_entry (req, &ep->queue, queue) { unsigned length = req->req.actual; seq_printf(s, "\treq %p len %d/%d buf %p\n", &req->req, length, req->req.length, req->req.buf); } local_irq_restore(flags); } static void proc_irq_show(struct seq_file *s, const char *label, u32 mask) { int i; seq_printf(s, "%s %04x:%s%s" FOURBITS, label, mask, (mask & (1 << 13)) ? " wakeup" : "", (mask & (1 << 12)) ? " endbusres" : "", (mask & (1 << 11)) ? " sofint" : "", (mask & (1 << 10)) ? " extrsm" : "", (mask & (1 << 9)) ? " rxrsm" : "", (mask & (1 << 8)) ? " rxsusp" : ""); for (i = 0; i < 8; i++) { if (mask & (1 << i)) seq_printf(s, " ep%d", i); } seq_printf(s, "\n"); } static int proc_udc_show(struct seq_file *s, void *unused) { struct at91_udc *udc = s->private; struct at91_ep *ep; u32 tmp; seq_printf(s, "%s: version %s\n", driver_name, DRIVER_VERSION); seq_printf(s, "vbus %s, pullup %s, %s powered%s, gadget %s\n\n", udc->vbus ? "present" : "off", udc->enabled ? (udc->vbus ? "active" : "enabled") : "disabled", udc->selfpowered ? "self" : "VBUS", udc->suspended ? ", suspended" : "", udc->driver ? udc->driver->driver.name : "(none)"); /* don't access registers when interface isn't clocked */ if (!udc->clocked) { seq_printf(s, "(not clocked)\n"); return 0; } tmp = at91_udp_read(AT91_UDP_FRM_NUM); seq_printf(s, "frame %05x:%s%s frame=%d\n", tmp, (tmp & AT91_UDP_FRM_OK) ? " ok" : "", (tmp & AT91_UDP_FRM_ERR) ? " err" : "", (tmp & AT91_UDP_NUM)); tmp = at91_udp_read(AT91_UDP_GLB_STAT); seq_printf(s, "glbstate %02x:%s" FOURBITS "\n", tmp, (tmp & AT91_UDP_RMWUPE) ? " rmwupe" : "", (tmp & AT91_UDP_RSMINPR) ? " rsminpr" : "", (tmp & AT91_UDP_ESR) ? " esr" : "", (tmp & AT91_UDP_CONFG) ? " confg" : "", (tmp & AT91_UDP_FADDEN) ? " fadden" : ""); tmp = at91_udp_read(AT91_UDP_FADDR); seq_printf(s, "faddr %03x:%s fadd=%d\n", tmp, (tmp & AT91_UDP_FEN) ? " fen" : "", (tmp & AT91_UDP_FADD)); proc_irq_show(s, "imr ", at91_udp_read(AT91_UDP_IMR)); proc_irq_show(s, "isr ", at91_udp_read(AT91_UDP_ISR)); if (udc->enabled && udc->vbus) { proc_ep_show(s, &udc->ep[0]); list_for_each_entry (ep, &udc->gadget.ep_list, ep.ep_list) { if (ep->desc) proc_ep_show(s, ep); } } return 0; } static int proc_udc_open(struct inode *inode, struct file *file) { return single_open(file, proc_udc_show, PDE(inode)->data); } static struct file_operations proc_ops = { .open = proc_udc_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static void create_debug_file(struct at91_udc *udc) { struct proc_dir_entry *pde; pde = create_proc_entry (debug_filename, 0, NULL); udc->pde = pde; if (pde == NULL) return; pde->proc_fops = &proc_ops; pde->data = udc; } static void remove_debug_file(struct at91_udc *udc) { if (udc->pde) remove_proc_entry(debug_filename, NULL); } #else static inline void create_debug_file(struct at91_udc *udc) {} static inline void remove_debug_file(struct at91_udc *udc) {} #endif /*-------------------------------------------------------------------------*/ static void done(struct at91_ep *ep, struct at91_request *req, int status) { unsigned stopped = ep->stopped; list_del_init(&req->queue); if (req->req.status == -EINPROGRESS) req->req.status = status; else status = req->req.status; if (status && status != -ESHUTDOWN) VDBG("%s done %p, status %d\n", ep->ep.name, req, status); ep->stopped = 1; req->req.complete(&ep->ep, &req->req); ep->stopped = stopped; /* ep0 is always ready; other endpoints need a non-empty queue */ if (list_empty(&ep->queue) && ep->int_mask != (1 << 0)) at91_udp_write(AT91_UDP_IDR, ep->int_mask); } /*-------------------------------------------------------------------------*/ /* bits indicating OUT fifo has data ready */ #define RX_DATA_READY (AT91_UDP_RX_DATA_BK0 | AT91_UDP_RX_DATA_BK1) /* * Endpoint FIFO CSR bits have a mix of bits, making it unsafe to just write * back most of the value you just read (because of side effects, including * bits that may change after reading and before writing). * * Except when changing a specific bit, always write values which: * - clear SET_FX bits (setting them could change something) * - set CLR_FX bits (clearing them could change something) * * There are also state bits like FORCESTALL, EPEDS, DIR, and EPTYPE * that shouldn't normally be changed. */ #define SET_FX (AT91_UDP_TXPKTRDY) #define CLR_FX (RX_DATA_READY | AT91_UDP_RXSETUP | AT91_UDP_STALLSENT | AT91_UDP_TXCOMP) /* pull OUT packet data from the endpoint's fifo */ static int read_fifo (struct at91_ep *ep, struct at91_request *req) { u32 __iomem *creg = ep->creg; u8 __iomem *dreg = ep->creg + (AT91_UDP_FDR(0) - AT91_UDP_CSR(0)); u32 csr; u8 *buf; unsigned int count, bufferspace, is_done; buf = req->req.buf + req->req.actual; bufferspace = req->req.length - req->req.actual; /* * there might be nothing to read if ep_queue() calls us, * or if we already emptied both pingpong buffers */ rescan: csr = __raw_readl(creg); if ((csr & RX_DATA_READY) == 0) return 0; count = (csr & AT91_UDP_RXBYTECNT) >> 16; if (count > ep->ep.maxpacket) count = ep->ep.maxpacket; if (count > bufferspace) { DBG("%s buffer overflow\n", ep->ep.name); req->req.status = -EOVERFLOW; count = bufferspace; } __raw_readsb(dreg, buf, count); /* release and swap pingpong mem bank */ csr |= CLR_FX; if (ep->is_pingpong) { if (ep->fifo_bank == 0) { csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK0); ep->fifo_bank = 1; } else { csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK1); ep->fifo_bank = 0; } } else csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK0); __raw_writel(csr, creg); req->req.actual += count; is_done = (count < ep->ep.maxpacket); if (count == bufferspace) is_done = 1; PACKET("%s %p out/%d%s\n", ep->ep.name, &req->req, count, is_done ? " (done)" : ""); /* * avoid extra trips through IRQ logic for packets already in * the fifo ... maybe preventing an extra (expensive) OUT-NAK */ if (is_done) done(ep, req, 0); else if (ep->is_pingpong) { bufferspace -= count; buf += count; goto rescan; } return is_done; } /* load fifo for an IN packet */ static int write_fifo(struct at91_ep *ep, struct at91_request *req) { u32 __iomem *creg = ep->creg; u32 csr = __raw_readl(creg); u8 __iomem *dreg = ep->creg + (AT91_UDP_FDR(0) - AT91_UDP_CSR(0)); unsigned total, count, is_last; /* * TODO: allow for writing two packets to the fifo ... that'll * reduce the amount of IN-NAKing, but probably won't affect * throughput much. (Unlike preventing OUT-NAKing!) */ /* * If ep_queue() calls us, the queue is empty and possibly in * odd states like TXCOMP not yet cleared (we do it, saving at * least one IRQ) or the fifo not yet being free. Those aren't * issues normally (IRQ handler fast path). */ if (unlikely(csr & (AT91_UDP_TXCOMP | AT91_UDP_TXPKTRDY))) { if (csr & AT91_UDP_TXCOMP) { csr |= CLR_FX; csr &= ~(SET_FX | AT91_UDP_TXCOMP); __raw_writel(csr, creg); csr = __raw_readl(creg); } if (csr & AT91_UDP_TXPKTRDY) return 0; } total = req->req.length - req->req.actual; if (ep->ep.maxpacket < total) { count = ep->ep.maxpacket; is_last = 0; } else { count = total; is_last = (count < ep->ep.maxpacket) || !req->req.zero; } /* * Write the packet, maybe it's a ZLP. * * NOTE: incrementing req->actual before we receive the ACK means * gadget driver IN bytecounts can be wrong in fault cases. That's * fixable with PIO drivers like this one (save "count" here, and * do the increment later on TX irq), but not for most DMA hardware. * * So all gadget drivers must accept that potential error. Some * hardware supports precise fifo status reporting, letting them * recover when the actual bytecount matters (e.g. for USB Test * and Measurement Class devices). */ __raw_writesb(dreg, req->req.buf + req->req.actual, count); csr &= ~SET_FX; csr |= CLR_FX | AT91_UDP_TXPKTRDY; __raw_writel(csr, creg); req->req.actual += count; PACKET("%s %p in/%d%s\n", ep->ep.name, &req->req, count, is_last ? " (done)" : ""); if (is_last) done(ep, req, 0); return is_last; } static void nuke(struct at91_ep *ep, int status) { struct at91_request *req; // terminer chaque requete dans la queue ep->stopped = 1; if (list_empty(&ep->queue)) return; VDBG("%s %s\n", __FUNCTION__, ep->ep.name); while (!list_empty(&ep->queue)) { req = list_entry(ep->queue.next, struct at91_request, queue); done(ep, req, status); } } /*-------------------------------------------------------------------------*/ static int at91_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc) { struct at91_ep *ep = container_of(_ep, struct at91_ep, ep); struct at91_udc *dev = ep->udc; u16 maxpacket; u32 tmp; unsigned long flags; if (!_ep || !ep || !desc || ep->desc || _ep->name == ep0name || desc->bDescriptorType != USB_DT_ENDPOINT || (maxpacket = le16_to_cpu(desc->wMaxPacketSize)) == 0 || maxpacket > ep->maxpacket) { DBG("bad ep or descriptor\n"); return -EINVAL; } if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) { DBG("bogus device state\n"); return -ESHUTDOWN; } tmp = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; switch (tmp) { case USB_ENDPOINT_XFER_CONTROL: DBG("only one control endpoint\n"); return -EINVAL; case USB_ENDPOINT_XFER_INT: if (maxpacket > 64) goto bogus_max; break; case USB_ENDPOINT_XFER_BULK: switch (maxpacket) { case 8: case 16: case 32: case 64: goto ok; } bogus_max: DBG("bogus maxpacket %d\n", maxpacket); return -EINVAL; case USB_ENDPOINT_XFER_ISOC: if (!ep->is_pingpong) { DBG("iso requires double buffering\n"); return -EINVAL; } break; } ok: local_irq_save(flags); /* initialize endpoint to match this descriptor */ ep->is_in = (desc->bEndpointAddress & USB_DIR_IN) != 0; ep->is_iso = (tmp == USB_ENDPOINT_XFER_ISOC); ep->stopped = 0; if (ep->is_in) tmp |= 0x04; tmp <<= 8; tmp |= AT91_UDP_EPEDS; __raw_writel(tmp, ep->creg); ep->desc = desc; ep->ep.maxpacket = maxpacket; /* * reset/init endpoint fifo. NOTE: leaves fifo_bank alone, * since endpoint resets don't reset hw pingpong state. */ at91_udp_write(AT91_UDP_RST_EP, ep->int_mask); at91_udp_write(AT91_UDP_RST_EP, 0); local_irq_restore(flags); return 0; } static int at91_ep_disable (struct usb_ep * _ep) { struct at91_ep *ep = container_of(_ep, struct at91_ep, ep); unsigned long flags; if (ep == &ep->udc->ep[0]) return -EINVAL; local_irq_save(flags); nuke(ep, -ESHUTDOWN); /* restore the endpoint's pristine config */ ep->desc = NULL; ep->ep.maxpacket = ep->maxpacket; /* reset fifos and endpoint */ if (ep->udc->clocked) { at91_udp_write(AT91_UDP_RST_EP, ep->int_mask); at91_udp_write(AT91_UDP_RST_EP, 0); __raw_writel(0, ep->creg); } local_irq_restore(flags); return 0; } /* * this is a PIO-only driver, so there's nothing * interesting for request or buffer allocation. */ static struct usb_request *at91_ep_alloc_request (struct usb_ep *_ep, unsigned int gfp_flags) { struct at91_request *req; req = kcalloc(1, sizeof (struct at91_request), SLAB_KERNEL); if (!req) return NULL; INIT_LIST_HEAD(&req->queue); return &req->req; } static void at91_ep_free_request(struct usb_ep *_ep, struct usb_request *_req) { struct at91_request *req; req = container_of(_req, struct at91_request, req); BUG_ON(!list_empty(&req->queue)); kfree(req); } static void *at91_ep_alloc_buffer( struct usb_ep *_ep, unsigned bytes, dma_addr_t *dma, gfp_t gfp_flags) { *dma = ~0; return kmalloc(bytes, gfp_flags); } static void at91_ep_free_buffer( struct usb_ep *ep, void *buf, dma_addr_t dma, unsigned bytes) { kfree(buf); } static int at91_ep_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags) { struct at91_request *req; struct at91_ep *ep; struct at91_udc *dev; int status; unsigned long flags; req = container_of(_req, struct at91_request, req); ep = container_of(_ep, struct at91_ep, ep); if (!_req || !_req->complete || !_req->buf || !list_empty(&req->queue)) { DBG("invalid request\n"); return -EINVAL; } if (!_ep || (!ep->desc && ep->ep.name != ep0name)) { DBG("invalid ep\n"); return -EINVAL; } dev = ep->udc; if (!dev || !dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) { DBG("invalid device\n"); return -EINVAL; } _req->status = -EINPROGRESS; _req->actual = 0; local_irq_save(flags); /* try to kickstart any empty and idle queue */ if (list_empty(&ep->queue) && !ep->stopped) { int is_ep0; /* * If this control request has a non-empty DATA stage, this * will start that stage. It works just like a non-control * request (until the status stage starts, maybe early). * * If the data stage is empty, then this starts a successful * IN/STATUS stage. (Unsuccessful ones use set_halt.) */ is_ep0 = (ep->ep.name == ep0name); if (is_ep0) { u32 tmp; if (!dev->req_pending) { status = -EINVAL; goto done; } /* * defer changing CONFG until after the gadget driver * reconfigures the endpoints. */ if (dev->wait_for_config_ack) { tmp = at91_udp_read(AT91_UDP_GLB_STAT); tmp ^= AT91_UDP_CONFG; VDBG("toggle config\n"); at91_udp_write(AT91_UDP_GLB_STAT, tmp); } if (req->req.length == 0) { ep0_in_status: PACKET("ep0 in/status\n"); status = 0; tmp = __raw_readl(ep->creg); tmp &= ~SET_FX; tmp |= CLR_FX | AT91_UDP_TXPKTRDY; __raw_writel(tmp, ep->creg); dev->req_pending = 0; goto done; } } if (ep->is_in) status = write_fifo(ep, req); else { status = read_fifo(ep, req); /* IN/STATUS stage is otherwise triggered by irq */ if (status && is_ep0) goto ep0_in_status; } } else status = 0; if (req && !status) { list_add_tail (&req->queue, &ep->queue); at91_udp_write(AT91_UDP_IER, ep->int_mask); } done: local_irq_restore(flags); return (status < 0) ? status : 0; } static int at91_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req) { struct at91_ep *ep; struct at91_request *req; ep = container_of(_ep, struct at91_ep, ep); if (!_ep || ep->ep.name == ep0name) return -EINVAL; /* make sure it's actually queued on this endpoint */ list_for_each_entry (req, &ep->queue, queue) { if (&req->req == _req) break; } if (&req->req != _req) return -EINVAL; done(ep, req, -ECONNRESET); return 0; } static int at91_ep_set_halt(struct usb_ep *_ep, int value) { struct at91_ep *ep = container_of(_ep, struct at91_ep, ep); u32 __iomem *creg; u32 csr; unsigned long flags; int status = 0; if (!_ep || ep->is_iso || !ep->udc->clocked) return -EINVAL; creg = ep->creg; local_irq_save(flags); csr = __raw_readl(creg); /* * fail with still-busy IN endpoints, ensuring correct sequencing * of data tx then stall. note that the fifo rx bytecount isn't * completely accurate as a tx bytecount. */ if (ep->is_in && (!list_empty(&ep->queue) || (csr >> 16) != 0)) status = -EAGAIN; else { csr |= CLR_FX; csr &= ~SET_FX; if (value) { csr |= AT91_UDP_FORCESTALL; VDBG("halt %s\n", ep->ep.name); } else { at91_udp_write(AT91_UDP_RST_EP, ep->int_mask); at91_udp_write(AT91_UDP_RST_EP, 0); csr &= ~AT91_UDP_FORCESTALL; } __raw_writel(csr, creg); } local_irq_restore(flags); return status; } static struct usb_ep_ops at91_ep_ops = { .enable = at91_ep_enable, .disable = at91_ep_disable, .alloc_request = at91_ep_alloc_request, .free_request = at91_ep_free_request, .alloc_buffer = at91_ep_alloc_buffer, .free_buffer = at91_ep_free_buffer, .queue = at91_ep_queue, .dequeue = at91_ep_dequeue, .set_halt = at91_ep_set_halt, // there's only imprecise fifo status reporting }; /*-------------------------------------------------------------------------*/ static int at91_get_frame(struct usb_gadget *gadget) { if (!to_udc(gadget)->clocked) return -EINVAL; return at91_udp_read(AT91_UDP_FRM_NUM) & AT91_UDP_NUM; } static int at91_wakeup(struct usb_gadget *gadget) { struct at91_udc *udc = to_udc(gadget); u32 glbstate; int status = -EINVAL; unsigned long flags; DBG("%s\n", __FUNCTION__ ); local_irq_save(flags); if (!udc->clocked || !udc->suspended) goto done; /* NOTE: some "early versions" handle ESR differently ... */ glbstate = at91_udp_read(AT91_UDP_GLB_STAT); if (!(glbstate & AT91_UDP_ESR)) goto done; glbstate |= AT91_UDP_ESR; at91_udp_write(AT91_UDP_GLB_STAT, glbstate); done: local_irq_restore(flags); return status; } /* reinit == restore inital software state */ static void udc_reinit(struct at91_udc *udc) { u32 i; INIT_LIST_HEAD(&udc->gadget.ep_list); INIT_LIST_HEAD(&udc->gadget.ep0->ep_list); for (i = 0; i < NUM_ENDPOINTS; i++) { struct at91_ep *ep = &udc->ep[i]; if (i != 0) list_add_tail(&ep->ep.ep_list, &udc->gadget.ep_list); ep->desc = NULL; ep->stopped = 0; ep->fifo_bank = 0; ep->ep.maxpacket = ep->maxpacket; // initialiser une queue par endpoint INIT_LIST_HEAD(&ep->queue); } } static void stop_activity(struct at91_udc *udc) { struct usb_gadget_driver *driver = udc->driver; int i; if (udc->gadget.speed == USB_SPEED_UNKNOWN) driver = NULL; udc->gadget.speed = USB_SPEED_UNKNOWN; for (i = 0; i < NUM_ENDPOINTS; i++) { struct at91_ep *ep = &udc->ep[i]; ep->stopped = 1; nuke(ep, -ESHUTDOWN); } if (driver) driver->disconnect(&udc->gadget); udc_reinit(udc); } static void clk_on(struct at91_udc *udc) { if (udc->clocked) return; udc->clocked = 1; clk_enable(udc->iclk); clk_enable(udc->fclk); } static void clk_off(struct at91_udc *udc) { if (!udc->clocked) return; udc->clocked = 0; udc->gadget.speed = USB_SPEED_UNKNOWN; clk_disable(udc->iclk); clk_disable(udc->fclk); } /* * activate/deactivate link with host; minimize power usage for * inactive links by cutting clocks and transceiver power. */ static void pullup(struct at91_udc *udc, int is_on) { if (!udc->enabled || !udc->vbus) is_on = 0; DBG("%sactive\n", is_on ? "" : "in"); if (is_on) { clk_on(udc); at91_udp_write(AT91_UDP_TXVC, 0); at91_set_gpio_value(udc->board.pullup_pin, 1); } else { stop_activity(udc); at91_udp_write(AT91_UDP_TXVC, AT91_UDP_TXVC_TXVDIS); at91_set_gpio_value(udc->board.pullup_pin, 0); clk_off(udc); // REVISIT: with transceiver disabled, will D- float // so that a host would falsely detect a device? } } /* vbus is here! turn everything on that's ready */ static int at91_vbus_session(struct usb_gadget *gadget, int is_active) { struct at91_udc *udc = to_udc(gadget); unsigned long flags; // VDBG("vbus %s\n", is_active ? "on" : "off"); local_irq_save(flags); udc->vbus = (is_active != 0); pullup(udc, is_active); local_irq_restore(flags); return 0; } static int at91_pullup(struct usb_gadget *gadget, int is_on) { struct at91_udc *udc = to_udc(gadget); unsigned long flags; local_irq_save(flags); udc->enabled = is_on = !!is_on; pullup(udc, is_on); local_irq_restore(flags); return 0; } static int at91_set_selfpowered(struct usb_gadget *gadget, int is_on) { struct at91_udc *udc = to_udc(gadget); unsigned long flags; local_irq_save(flags); udc->selfpowered = (is_on != 0); local_irq_restore(flags); return 0; } static const struct usb_gadget_ops at91_udc_ops = { .get_frame = at91_get_frame, .wakeup = at91_wakeup, .set_selfpowered = at91_set_selfpowered, .vbus_session = at91_vbus_session, .pullup = at91_pullup, /* * VBUS-powered devices may also also want to support bigger * power budgets after an appropriate SET_CONFIGURATION. */ // .vbus_power = at91_vbus_power, }; /*-------------------------------------------------------------------------*/ static int handle_ep(struct at91_ep *ep) { struct at91_request *req; u32 __iomem *creg = ep->creg; u32 csr = __raw_readl(creg); if (!list_empty(&ep->queue)) req = list_entry(ep->queue.next, struct at91_request, queue); else req = NULL; if (ep->is_in) { if (csr & (AT91_UDP_STALLSENT | AT91_UDP_TXCOMP)) { csr |= CLR_FX; csr &= ~(SET_FX | AT91_UDP_STALLSENT | AT91_UDP_TXCOMP); __raw_writel(csr, creg); } if (req) return write_fifo(ep, req); } else { if (csr & AT91_UDP_STALLSENT) { /* STALLSENT bit == ISOERR */ if (ep->is_iso && req) req->req.status = -EILSEQ; csr |= CLR_FX; csr &= ~(SET_FX | AT91_UDP_STALLSENT); __raw_writel(csr, creg); csr = __raw_readl(creg); } if (req && (csr & RX_DATA_READY)) return read_fifo(ep, req); } return 0; } union setup { u8 raw[8]; struct usb_ctrlrequest r; }; static void handle_setup(struct at91_udc *udc, struct at91_ep *ep, u32 csr) { u32 __iomem *creg = ep->creg; u8 __iomem *dreg = ep->creg + (AT91_UDP_FDR(0) - AT91_UDP_CSR(0)); unsigned rxcount, i = 0; u32 tmp; union setup pkt; int status = 0; /* read and ack SETUP; hard-fail for bogus packets */ rxcount = (csr & AT91_UDP_RXBYTECNT) >> 16; if (likely(rxcount == 8)) { while (rxcount--) pkt.raw[i++] = __raw_readb(dreg); if (pkt.r.bRequestType & USB_DIR_IN) { csr |= AT91_UDP_DIR; ep->is_in = 1; } else { csr &= ~AT91_UDP_DIR; ep->is_in = 0; } } else { // REVISIT this happens sometimes under load; why?? ERR("SETUP len %d, csr %08x\n", rxcount, csr); status = -EINVAL; } csr |= CLR_FX; csr &= ~(SET_FX | AT91_UDP_RXSETUP); __raw_writel(csr, creg); udc->wait_for_addr_ack = 0; udc->wait_for_config_ack = 0; ep->stopped = 0; if (unlikely(status != 0)) goto stall; #define w_index le16_to_cpu(pkt.r.wIndex) #define w_value le16_to_cpu(pkt.r.wValue) #define w_length le16_to_cpu(pkt.r.wLength) VDBG("SETUP %02x.%02x v%04x i%04x l%04x\n", pkt.r.bRequestType, pkt.r.bRequest, w_value, w_index, w_length); /* * A few standard requests get handled here, ones that touch * hardware ... notably for device and endpoint features. */ udc->req_pending = 1; csr = __raw_readl(creg); csr |= CLR_FX; csr &= ~SET_FX; switch ((pkt.r.bRequestType << 8) | pkt.r.bRequest) { case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8) | USB_REQ_SET_ADDRESS: __raw_writel(csr | AT91_UDP_TXPKTRDY, creg); udc->addr = w_value; udc->wait_for_addr_ack = 1; udc->req_pending = 0; /* FADDR is set later, when we ack host STATUS */ return; case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8) | USB_REQ_SET_CONFIGURATION: tmp = at91_udp_read(AT91_UDP_GLB_STAT) & AT91_UDP_CONFG; if (pkt.r.wValue) udc->wait_for_config_ack = (tmp == 0); else udc->wait_for_config_ack = (tmp != 0); if (udc->wait_for_config_ack) VDBG("wait for config\n"); /* CONFG is toggled later, if gadget driver succeeds */ break; /* * Hosts may set or clear remote wakeup status, and * devices may report they're VBUS powered. */ case ((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8) | USB_REQ_GET_STATUS: tmp = (udc->selfpowered << USB_DEVICE_SELF_POWERED); if (at91_udp_read(AT91_UDP_GLB_STAT) & AT91_UDP_ESR) tmp |= (1 << USB_DEVICE_REMOTE_WAKEUP); PACKET("get device status\n"); __raw_writeb(tmp, dreg); __raw_writeb(0, dreg); goto write_in; /* then STATUS starts later, automatically */ case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8) | USB_REQ_SET_FEATURE: if (w_value != USB_DEVICE_REMOTE_WAKEUP) goto stall; tmp = at91_udp_read(AT91_UDP_GLB_STAT); tmp |= AT91_UDP_ESR; at91_udp_write(AT91_UDP_GLB_STAT, tmp); goto succeed; case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8) | USB_REQ_CLEAR_FEATURE: if (w_value != USB_DEVICE_REMOTE_WAKEUP) goto stall; tmp = at91_udp_read(AT91_UDP_GLB_STAT); tmp &= ~AT91_UDP_ESR; at91_udp_write(AT91_UDP_GLB_STAT, tmp); goto succeed; /* * Interfaces have no feature settings; this is pretty useless. * we won't even insist the interface exists... */ case ((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_INTERFACE) << 8) | USB_REQ_GET_STATUS: PACKET("get interface status\n"); __raw_writeb(0, dreg); __raw_writeb(0, dreg); goto write_in; /* then STATUS starts later, automatically */ case ((USB_TYPE_STANDARD|USB_RECIP_INTERFACE) << 8) | USB_REQ_SET_FEATURE: case ((USB_TYPE_STANDARD|USB_RECIP_INTERFACE) << 8) | USB_REQ_CLEAR_FEATURE: goto stall; /* * Hosts may clear bulk/intr endpoint halt after the gadget * driver sets it (not widely used); or set it (for testing) */ case ((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_ENDPOINT) << 8) | USB_REQ_GET_STATUS: tmp = w_index & USB_ENDPOINT_NUMBER_MASK; ep = &udc->ep[tmp]; if (tmp > NUM_ENDPOINTS || (tmp && !ep->desc)) goto stall; if (tmp) { if ((w_index & USB_DIR_IN)) { if (!ep->is_in) goto stall; } else if (ep->is_in) goto stall; } PACKET("get %s status\n", ep->ep.name); if (__raw_readl(ep->creg) & AT91_UDP_FORCESTALL) tmp = (1 << USB_ENDPOINT_HALT); else tmp = 0; __raw_writeb(tmp, dreg); __raw_writeb(0, dreg); goto write_in; /* then STATUS starts later, automatically */ case ((USB_TYPE_STANDARD|USB_RECIP_ENDPOINT) << 8) | USB_REQ_SET_FEATURE: tmp = w_index & USB_ENDPOINT_NUMBER_MASK; ep = &udc->ep[tmp]; if (w_value != USB_ENDPOINT_HALT || tmp > NUM_ENDPOINTS) goto stall; if (!ep->desc || ep->is_iso) goto stall; if ((w_index & USB_DIR_IN)) { if (!ep->is_in) goto stall; } else if (ep->is_in) goto stall; tmp = __raw_readl(ep->creg); tmp &= ~SET_FX; tmp |= CLR_FX | AT91_UDP_FORCESTALL; __raw_writel(tmp, ep->creg); goto succeed; case ((USB_TYPE_STANDARD|USB_RECIP_ENDPOINT) << 8) | USB_REQ_CLEAR_FEATURE: tmp = w_index & USB_ENDPOINT_NUMBER_MASK; ep = &udc->ep[tmp]; if (w_value != USB_ENDPOINT_HALT || tmp > NUM_ENDPOINTS) goto stall; if (tmp == 0) goto succeed; if (!ep->desc || ep->is_iso) goto stall; if ((w_index & USB_DIR_IN)) { if (!ep->is_in) goto stall; } else if (ep->is_in) goto stall; at91_udp_write(AT91_UDP_RST_EP, ep->int_mask); at91_udp_write(AT91_UDP_RST_EP, 0); tmp = __raw_readl(ep->creg); tmp |= CLR_FX; tmp &= ~(SET_FX | AT91_UDP_FORCESTALL); __raw_writel(tmp, ep->creg); if (!list_empty(&ep->queue)) handle_ep(ep); goto succeed; } #undef w_value #undef w_index #undef w_length /* pass request up to the gadget driver */ status = udc->driver->setup(&udc->gadget, &pkt.r); if (status < 0) { stall: VDBG("req %02x.%02x protocol STALL; stat %d\n", pkt.r.bRequestType, pkt.r.bRequest, status); csr |= AT91_UDP_FORCESTALL; __raw_writel(csr, creg); udc->req_pending = 0; } return; succeed: /* immediate successful (IN) STATUS after zero length DATA */ PACKET("ep0 in/status\n"); write_in: csr |= AT91_UDP_TXPKTRDY; __raw_writel(csr, creg); udc->req_pending = 0; return; } static void handle_ep0(struct at91_udc *udc) { struct at91_ep *ep0 = &udc->ep[0]; u32 __iomem *creg = ep0->creg; u32 csr = __raw_readl(creg); struct at91_request *req; if (unlikely(csr & AT91_UDP_STALLSENT)) { nuke(ep0, -EPROTO); udc->req_pending = 0; csr |= CLR_FX; csr &= ~(SET_FX | AT91_UDP_STALLSENT | AT91_UDP_FORCESTALL); __raw_writel(csr, creg); VDBG("ep0 stalled\n"); csr = __raw_readl(creg); } if (csr & AT91_UDP_RXSETUP) { nuke(ep0, 0); udc->req_pending = 0; handle_setup(udc, ep0, csr); return; } if (list_empty(&ep0->queue)) req = NULL; else req = list_entry(ep0->queue.next, struct at91_request, queue); /* host ACKed an IN packet that we sent */ if (csr & AT91_UDP_TXCOMP) { csr |= CLR_FX; csr &= ~(SET_FX | AT91_UDP_TXCOMP); /* write more IN DATA? */ if (req && ep0->is_in) { if (handle_ep(ep0)) udc->req_pending = 0; /* * Ack after: * - last IN DATA packet (including GET_STATUS) * - IN/STATUS for OUT DATA * - IN/STATUS for any zero-length DATA stage * except for the IN DATA case, the host should send * an OUT status later, which we'll ack. */ } else { udc->req_pending = 0; __raw_writel(csr, creg); /* * SET_ADDRESS takes effect only after the STATUS * (to the original address) gets acked. */ if (udc->wait_for_addr_ack) { u32 tmp; at91_udp_write(AT91_UDP_FADDR, AT91_UDP_FEN | udc->addr); tmp = at91_udp_read(AT91_UDP_GLB_STAT); tmp &= ~AT91_UDP_FADDEN; if (udc->addr) tmp |= AT91_UDP_FADDEN; at91_udp_write(AT91_UDP_GLB_STAT, tmp); udc->wait_for_addr_ack = 0; VDBG("address %d\n", udc->addr); } } } /* OUT packet arrived ... */ else if (csr & AT91_UDP_RX_DATA_BK0) { csr |= CLR_FX; csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK0); /* OUT DATA stage */ if (!ep0->is_in) { if (req) { if (handle_ep(ep0)) { /* send IN/STATUS */ PACKET("ep0 in/status\n"); csr = __raw_readl(creg); csr &= ~SET_FX; csr |= CLR_FX | AT91_UDP_TXPKTRDY; __raw_writel(csr, creg); udc->req_pending = 0; } } else if (udc->req_pending) { /* * AT91 hardware has a hard time with this * "deferred response" mode for control-OUT * transfers. (For control-IN it's fine.) * * The normal solution leaves OUT data in the * fifo until the gadget driver is ready. * We couldn't do that here without disabling * the IRQ that tells about SETUP packets, * e.g. when the host gets impatient... * * Working around it by copying into a buffer * would almost be a non-deferred response, * except that it wouldn't permit reliable * stalling of the request. Instead, demand * that gadget drivers not use this mode. */ DBG("no control-OUT deferred responses!\n"); __raw_writel(csr | AT91_UDP_FORCESTALL, creg); udc->req_pending = 0; } /* STATUS stage for control-IN; ack. */ } else { PACKET("ep0 out/status ACK\n"); __raw_writel(csr, creg); /* "early" status stage */ if (req) done(ep0, req, 0); } } } static irqreturn_t at91_udc_irq (int irq, void *_udc, struct pt_regs *r) { struct at91_udc *udc = _udc; u32 rescans = 5; while (rescans--) { u32 status = at91_udp_read(AT91_UDP_ISR); status &= at91_udp_read(AT91_UDP_IMR); if (!status) break; /* USB reset irq: not maskable */ if (status & AT91_UDP_ENDBUSRES) { at91_udp_write(AT91_UDP_IDR, ~MINIMUS_INTERRUPTUS); at91_udp_write(AT91_UDP_IER, MINIMUS_INTERRUPTUS); /* Atmel code clears this irq twice */ at91_udp_write(AT91_UDP_ICR, AT91_UDP_ENDBUSRES); at91_udp_write(AT91_UDP_ICR, AT91_UDP_ENDBUSRES); VDBG("end bus reset\n"); udc->addr = 0; stop_activity(udc); /* enable ep0 */ at91_udp_write(AT91_UDP_CSR(0), AT91_UDP_EPEDS | AT91_UDP_EPTYPE_CTRL); udc->gadget.speed = USB_SPEED_FULL; udc->suspended = 0; at91_udp_write(AT91_UDP_IER, AT91_UDP_EP(0)); /* * NOTE: this driver keeps clocks off unless the * USB host is present. That saves power, and also * eliminates IRQs (reset, resume, suspend) that can * otherwise flood from the controller. If your * board doesn't support VBUS detection, suspend and * resume irq logic may need more attention... */ /* host initiated suspend (3+ms bus idle) */ } else if (status & AT91_UDP_RXSUSP) { at91_udp_write(AT91_UDP_IDR, AT91_UDP_RXSUSP); at91_udp_write(AT91_UDP_IER, AT91_UDP_RXRSM); at91_udp_write(AT91_UDP_ICR, AT91_UDP_RXSUSP); // VDBG("bus suspend\n"); if (udc->suspended) continue; udc->suspended = 1; /* * NOTE: when suspending a VBUS-powered device, the * gadget driver should switch into slow clock mode * and then into standby to avoid drawing more than * 500uA power (2500uA for some high-power configs). */ if (udc->driver && udc->driver->suspend) udc->driver->suspend(&udc->gadget); /* host initiated resume */ } else if (status & AT91_UDP_RXRSM) { at91_udp_write(AT91_UDP_IDR, AT91_UDP_RXRSM); at91_udp_write(AT91_UDP_IER, AT91_UDP_RXSUSP); at91_udp_write(AT91_UDP_ICR, AT91_UDP_RXRSM); // VDBG("bus resume\n"); if (!udc->suspended) continue; udc->suspended = 0; /* * NOTE: for a VBUS-powered device, the gadget driver * would normally want to switch out of slow clock * mode into normal mode. */ if (udc->driver && udc->driver->resume) udc->driver->resume(&udc->gadget); /* endpoint IRQs are cleared by handling them */ } else { int i; unsigned mask = 1; struct at91_ep *ep = &udc->ep[1]; if (status & mask) handle_ep0(udc); for (i = 1; i < NUM_ENDPOINTS; i++) { mask <<= 1; if (status & mask) handle_ep(ep); ep++; } } } return IRQ_HANDLED; } /*-------------------------------------------------------------------------*/ static struct at91_udc controller = { .gadget = { .ops = &at91_udc_ops, .ep0 = &controller.ep[0].ep, .name = driver_name, .dev = { .bus_id = "gadget" } }, .ep[0] = { .ep = { .name = ep0name, .ops = &at91_ep_ops, }, .udc = &controller, .maxpacket = 8, .creg = (void __iomem *)(AT91_VA_BASE_UDP + AT91_UDP_CSR(0)), .int_mask = 1 << 0, }, .ep[1] = { .ep = { .name = "ep1", .ops = &at91_ep_ops, }, .udc = &controller, .is_pingpong = 1, .maxpacket = 64, .creg = (void __iomem *)(AT91_VA_BASE_UDP + AT91_UDP_CSR(1)), .int_mask = 1 << 1, }, .ep[2] = { .ep = { .name = "ep2", .ops = &at91_ep_ops, }, .udc = &controller, .is_pingpong = 1, .maxpacket = 64, .creg = (void __iomem *)(AT91_VA_BASE_UDP + AT91_UDP_CSR(2)), .int_mask = 1 << 2, }, .ep[3] = { .ep = { /* could actually do bulk too */ .name = "ep3-int", .ops = &at91_ep_ops, }, .udc = &controller, .maxpacket = 8, .creg = (void __iomem *)(AT91_VA_BASE_UDP + AT91_UDP_CSR(3)), .int_mask = 1 << 3, }, .ep[4] = { .ep = { .name = "ep4", .ops = &at91_ep_ops, }, .udc = &controller, .is_pingpong = 1, .maxpacket = 256, .creg = (void __iomem *)(AT91_VA_BASE_UDP + AT91_UDP_CSR(4)), .int_mask = 1 << 4, }, .ep[5] = { .ep = { .name = "ep5", .ops = &at91_ep_ops, }, .udc = &controller, .is_pingpong = 1, .maxpacket = 256, .creg = (void __iomem *)(AT91_VA_BASE_UDP + AT91_UDP_CSR(5)), .int_mask = 1 << 5, }, /* ep6 and ep7 are also reserved */ }; static irqreturn_t at91_vbus_irq(int irq, void *_udc, struct pt_regs *r) { struct at91_udc *udc = _udc; unsigned value; /* vbus needs at least brief debouncing */ udelay(10); value = at91_get_gpio_value(udc->board.vbus_pin); if (value != udc->vbus) at91_vbus_session(&udc->gadget, value); return IRQ_HANDLED; } int usb_gadget_register_driver (struct usb_gadget_driver *driver) { struct at91_udc *udc = &controller; int retval; if (!driver || driver->speed != USB_SPEED_FULL || !driver->bind || !driver->unbind || !driver->setup) { DBG("bad parameter.\n"); return -EINVAL; } if (udc->driver) { DBG("UDC already has a gadget driver\n"); return -EBUSY; } udc->driver = driver; udc->gadget.dev.driver = &driver->driver; udc->gadget.dev.driver_data = &driver->driver; udc->enabled = 1; udc->selfpowered = 1; retval = driver->bind(&udc->gadget); if (retval) { DBG("driver->bind() returned %d\n", retval); udc->driver = NULL; return retval; } local_irq_disable(); pullup(udc, 1); local_irq_enable(); DBG("bound to %s\n", driver->driver.name); return 0; } EXPORT_SYMBOL (usb_gadget_register_driver); int usb_gadget_unregister_driver (struct usb_gadget_driver *driver) { struct at91_udc *udc = &controller; if (!driver || driver != udc->driver) return -EINVAL; local_irq_disable(); udc->enabled = 0; pullup(udc, 0); local_irq_enable(); driver->unbind(&udc->gadget); udc->driver = NULL; DBG("unbound from %s\n", driver->driver.name); return 0; } EXPORT_SYMBOL (usb_gadget_unregister_driver); /*-------------------------------------------------------------------------*/ static void at91udc_shutdown(struct platform_device *dev) { /* force disconnect on reboot */ pullup(platform_get_drvdata(dev), 0); } static int __devinit at91udc_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct at91_udc *udc; int retval; if (!dev->platform_data) { /* small (so we copy it) but critical! */ DBG("missing platform_data\n"); return -ENODEV; } if (!request_mem_region(AT91_BASE_UDP, SZ_16K, driver_name)) { DBG("someone's using UDC memory\n"); return -EBUSY; } /* init software state */ udc = &controller; udc->gadget.dev.parent = dev; udc->board = *(struct at91_udc_data *) dev->platform_data; udc->pdev = pdev; udc_reinit(udc); udc->enabled = 0; /* get interface and function clocks */ udc->iclk = clk_get(dev, "udc_clk"); udc->fclk = clk_get(dev, "udpck"); if (IS_ERR(udc->iclk) || IS_ERR(udc->fclk)) { DBG("clocks missing\n"); return -ENODEV; } retval = device_register(&udc->gadget.dev); if (retval < 0) goto fail0; /* disable everything until there's a gadget driver and vbus */ pullup(udc, 0); /* request UDC and maybe VBUS irqs */ if (request_irq(AT91_ID_UDP, at91_udc_irq, SA_INTERRUPT, driver_name, udc)) { DBG("request irq %d failed\n", AT91_ID_UDP); retval = -EBUSY; goto fail1; } if (udc->board.vbus_pin > 0) { if (request_irq(udc->board.vbus_pin, at91_vbus_irq, SA_INTERRUPT, driver_name, udc)) { DBG("request vbus irq %d failed\n", udc->board.vbus_pin); free_irq(AT91_ID_UDP, udc); retval = -EBUSY; goto fail1; } } else { DBG("no VBUS detection, assuming always-on\n"); udc->vbus = 1; } dev_set_drvdata(dev, udc); create_debug_file(udc); INFO("%s version %s\n", driver_name, DRIVER_VERSION); return 0; fail1: device_unregister(&udc->gadget.dev); fail0: release_mem_region(AT91_VA_BASE_UDP, SZ_16K); DBG("%s probe failed, %d\n", driver_name, retval); return retval; } static int __devexit at91udc_remove(struct platform_device *dev) { struct at91_udc *udc = platform_get_drvdata(dev); DBG("remove\n"); pullup(udc, 0); if (udc->driver != 0) usb_gadget_unregister_driver(udc->driver); remove_debug_file(udc); if (udc->board.vbus_pin > 0) free_irq(udc->board.vbus_pin, udc); free_irq(AT91_ID_UDP, udc); device_unregister(&udc->gadget.dev); release_mem_region(AT91_BASE_UDP, SZ_16K); clk_put(udc->iclk); clk_put(udc->fclk); return 0; } #ifdef CONFIG_PM static int at91udc_suspend(struct platform_device *dev, pm_message_t mesg) { struct at91_udc *udc = platform_get_drvdata(dev); /* * The "safe" suspend transitions are opportunistic ... e.g. when * the USB link is suspended (48MHz clock autogated off), or when * it's disconnected (programmatically gated off, elsewhere). * Then we can suspend, and the chip can enter slow clock mode. * * The problem case is some component (user mode?) suspending this * device while it's active, with the 48 MHz clock in use. There * are two basic approaches: (a) veto suspend levels involving slow * clock mode, (b) disconnect, so 48 MHz will no longer be in use * and we can enter slow clock mode. This uses (b) for now, since * it's simplest until AT91 PM exists and supports the other option. */ if (udc->vbus && !udc->suspended) pullup(udc, 0); return 0; } static int at91udc_resume(struct platform_device *dev) { struct at91_udc *udc = platform_get_drvdata(dev); /* maybe reconnect to host; if so, clocks on */ pullup(udc, 1); return 0; } #else #define at91udc_suspend NULL #define at91udc_resume NULL #endif static struct platform_driver at91_udc = { .probe = at91udc_probe, .remove = __devexit_p(at91udc_remove), .shutdown = at91udc_shutdown, .suspend = at91udc_suspend, .resume = at91udc_resume, .driver = { .name = (char *) driver_name, .owner = THIS_MODULE, }, }; static int __devinit udc_init_module(void) { return platform_driver_register(&at91_udc); } module_init(udc_init_module); static void __devexit udc_exit_module(void) { platform_driver_unregister(&at91_udc); } module_exit(udc_exit_module); MODULE_DESCRIPTION("AT91RM9200 udc driver"); MODULE_AUTHOR("Thomas Rathbone, David Brownell"); MODULE_LICENSE("GPL");