2 * MUSB OTG peripheral driver ep0 handling
4 * Copyright 2005 Mentor Graphics Corporation
5 * Copyright (C) 2005-2006 by Texas Instruments
6 * Copyright (C) 2006-2007 Nokia Corporation
7 * Copyright (C) 2008-2009 MontaVista Software, Inc. <source@mvista.com>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * version 2 as published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
23 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
26 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
29 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
30 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 #include <linux/kernel.h>
37 #include <linux/list.h>
38 #include <linux/timer.h>
39 #include <linux/spinlock.h>
40 #include <linux/init.h>
41 #include <linux/device.h>
42 #include <linux/interrupt.h>
44 #include "musb_core.h"
46 /* ep0 is always musb->endpoints[0].ep_in */
47 #define next_ep0_request(musb) next_in_request(&(musb)->endpoints[0])
50 * locking note: we use only the controller lock, for simpler correctness.
51 * It's always held with IRQs blocked.
53 * It protects the ep0 request queue as well as ep0_state, not just the
54 * controller and indexed registers. And that lock stays held unless it
55 * needs to be dropped to allow reentering this driver ... like upcalls to
56 * the gadget driver, or adjusting endpoint halt status.
59 static char *decode_ep0stage(u8 stage)
62 case MUSB_EP0_STAGE_IDLE: return "idle";
63 case MUSB_EP0_STAGE_SETUP: return "setup";
64 case MUSB_EP0_STAGE_TX: return "in";
65 case MUSB_EP0_STAGE_RX: return "out";
66 case MUSB_EP0_STAGE_ACKWAIT: return "wait";
67 case MUSB_EP0_STAGE_STATUSIN: return "in/status";
68 case MUSB_EP0_STAGE_STATUSOUT: return "out/status";
73 /* handle a standard GET_STATUS request
74 * Context: caller holds controller lock
76 static int service_tx_status_request(
78 const struct usb_ctrlrequest *ctrlrequest)
80 void __iomem *mbase = musb->mregs;
82 u8 result[2], epnum = 0;
83 const u8 recip = ctrlrequest->bRequestType & USB_RECIP_MASK;
88 case USB_RECIP_DEVICE:
89 result[0] = musb->is_self_powered << USB_DEVICE_SELF_POWERED;
90 result[0] |= musb->may_wakeup << USB_DEVICE_REMOTE_WAKEUP;
91 #ifdef CONFIG_USB_MUSB_OTG
93 result[0] |= musb->g.b_hnp_enable
94 << USB_DEVICE_B_HNP_ENABLE;
95 result[0] |= musb->g.a_alt_hnp_support
96 << USB_DEVICE_A_ALT_HNP_SUPPORT;
97 result[0] |= musb->g.a_hnp_support
98 << USB_DEVICE_A_HNP_SUPPORT;
103 case USB_RECIP_INTERFACE:
107 case USB_RECIP_ENDPOINT: {
113 epnum = (u8) ctrlrequest->wIndex;
119 is_in = epnum & USB_DIR_IN;
122 ep = &musb->endpoints[epnum].ep_in;
124 ep = &musb->endpoints[epnum].ep_out;
126 regs = musb->endpoints[epnum].regs;
128 if (epnum >= MUSB_C_NUM_EPS || !ep->desc) {
133 musb_ep_select(mbase, epnum);
135 tmp = musb_readw(regs, MUSB_TXCSR)
136 & MUSB_TXCSR_P_SENDSTALL;
138 tmp = musb_readw(regs, MUSB_RXCSR)
139 & MUSB_RXCSR_P_SENDSTALL;
140 musb_ep_select(mbase, 0);
142 result[0] = tmp ? 1 : 0;
146 /* class, vendor, etc ... delegate */
151 /* fill up the fifo; caller updates csr0 */
153 u16 len = le16_to_cpu(ctrlrequest->wLength);
157 musb_write_fifo(&musb->endpoints[0], len, result);
164 * handle a control-IN request, the end0 buffer contains the current request
165 * that is supposed to be a standard control request. Assumes the fifo to
166 * be at least 2 bytes long.
168 * @return 0 if the request was NOT HANDLED,
170 * > 0 when the request is processed
172 * Context: caller holds controller lock
175 service_in_request(struct musb *musb, const struct usb_ctrlrequest *ctrlrequest)
177 int handled = 0; /* not handled */
179 if ((ctrlrequest->bRequestType & USB_TYPE_MASK)
180 == USB_TYPE_STANDARD) {
181 switch (ctrlrequest->bRequest) {
182 case USB_REQ_GET_STATUS:
183 handled = service_tx_status_request(musb,
187 /* case USB_REQ_SYNC_FRAME: */
197 * Context: caller holds controller lock
199 static void musb_g_ep0_giveback(struct musb *musb, struct usb_request *req)
201 musb_g_giveback(&musb->endpoints[0].ep_in, req, 0);
202 musb->ep0_state = MUSB_EP0_STAGE_SETUP;
206 * Tries to start B-device HNP negotiation if enabled via sysfs
208 static inline void musb_try_b_hnp_enable(struct musb *musb)
210 void __iomem *mbase = musb->mregs;
213 DBG(1, "HNP: Setting HR\n");
214 devctl = musb_readb(mbase, MUSB_DEVCTL);
215 musb_writeb(mbase, MUSB_DEVCTL, devctl | MUSB_DEVCTL_HR);
219 * Handle all control requests with no DATA stage, including standard
221 * USB_REQ_SET_CONFIGURATION, USB_REQ_SET_INTERFACE, unrecognized
222 * always delegated to the gadget driver
223 * USB_REQ_SET_ADDRESS, USB_REQ_CLEAR_FEATURE, USB_REQ_SET_FEATURE
224 * always handled here, except for class/vendor/... features
226 * Context: caller holds controller lock
229 service_zero_data_request(struct musb *musb,
230 struct usb_ctrlrequest *ctrlrequest)
231 __releases(musb->lock)
232 __acquires(musb->lock)
234 int handled = -EINVAL;
235 void __iomem *mbase = musb->mregs;
236 const u8 recip = ctrlrequest->bRequestType & USB_RECIP_MASK;
238 /* the gadget driver handles everything except what we MUST handle */
239 if ((ctrlrequest->bRequestType & USB_TYPE_MASK)
240 == USB_TYPE_STANDARD) {
241 switch (ctrlrequest->bRequest) {
242 case USB_REQ_SET_ADDRESS:
243 /* change it after the status stage */
244 musb->set_address = true;
245 musb->address = (u8) (ctrlrequest->wValue & 0x7f);
249 case USB_REQ_CLEAR_FEATURE:
251 case USB_RECIP_DEVICE:
252 if (ctrlrequest->wValue
253 != USB_DEVICE_REMOTE_WAKEUP)
255 musb->may_wakeup = 0;
258 case USB_RECIP_INTERFACE:
260 case USB_RECIP_ENDPOINT:{
261 const u8 num = ctrlrequest->wIndex & 0x0f;
262 struct musb_ep *musb_ep;
265 || num >= MUSB_C_NUM_EPS
266 || ctrlrequest->wValue
267 != USB_ENDPOINT_HALT)
270 if (ctrlrequest->wIndex & USB_DIR_IN)
271 musb_ep = &musb->endpoints[num].ep_in;
273 musb_ep = &musb->endpoints[num].ep_out;
277 /* REVISIT do it directly, no locking games */
278 spin_unlock(&musb->lock);
279 musb_gadget_set_halt(&musb_ep->end_point, 0);
280 spin_lock(&musb->lock);
282 /* select ep0 again */
283 musb_ep_select(mbase, 0);
287 /* class, vendor, etc ... delegate */
293 case USB_REQ_SET_FEATURE:
295 case USB_RECIP_DEVICE:
297 switch (ctrlrequest->wValue) {
298 case USB_DEVICE_REMOTE_WAKEUP:
299 musb->may_wakeup = 1;
301 case USB_DEVICE_TEST_MODE:
302 if (musb->g.speed != USB_SPEED_HIGH)
304 if (ctrlrequest->wIndex & 0xff)
307 switch (ctrlrequest->wIndex >> 8) {
309 pr_debug("TEST_J\n");
316 pr_debug("TEST_K\n");
322 pr_debug("TEST_SE0_NAK\n");
328 pr_debug("TEST_PACKET\n");
336 /* enter test mode after irq */
338 musb->test_mode = true;
340 #ifdef CONFIG_USB_MUSB_OTG
341 case USB_DEVICE_B_HNP_ENABLE:
344 musb->g.b_hnp_enable = 1;
345 musb_try_b_hnp_enable(musb);
347 case USB_DEVICE_A_HNP_SUPPORT:
350 musb->g.a_hnp_support = 1;
352 case USB_DEVICE_A_ALT_HNP_SUPPORT:
355 musb->g.a_alt_hnp_support = 1;
365 case USB_RECIP_INTERFACE:
368 case USB_RECIP_ENDPOINT:{
370 ctrlrequest->wIndex & 0x0f;
371 struct musb_ep *musb_ep;
372 struct musb_hw_ep *ep;
378 || epnum >= MUSB_C_NUM_EPS
379 || ctrlrequest->wValue
380 != USB_ENDPOINT_HALT)
383 ep = musb->endpoints + epnum;
385 is_in = ctrlrequest->wIndex & USB_DIR_IN;
387 musb_ep = &ep->ep_in;
389 musb_ep = &ep->ep_out;
393 musb_ep_select(mbase, epnum);
395 csr = musb_readw(regs,
397 if (csr & MUSB_TXCSR_FIFONOTEMPTY)
398 csr |= MUSB_TXCSR_FLUSHFIFO;
399 csr |= MUSB_TXCSR_P_SENDSTALL
400 | MUSB_TXCSR_CLRDATATOG
401 | MUSB_TXCSR_P_WZC_BITS;
402 musb_writew(regs, MUSB_TXCSR,
405 csr = musb_readw(regs,
407 csr |= MUSB_RXCSR_P_SENDSTALL
408 | MUSB_RXCSR_FLUSHFIFO
409 | MUSB_RXCSR_CLRDATATOG
410 | MUSB_RXCSR_P_WZC_BITS;
411 musb_writew(regs, MUSB_RXCSR,
415 /* select ep0 again */
416 musb_ep_select(mbase, 0);
421 /* class, vendor, etc ... delegate */
427 /* delegate SET_CONFIGURATION, etc */
435 /* we have an ep0out data packet
436 * Context: caller holds controller lock
438 static void ep0_rxstate(struct musb *musb)
440 void __iomem *regs = musb->control_ep->regs;
441 struct usb_request *req;
444 req = next_ep0_request(musb);
446 /* read packet and ack; or stall because of gadget driver bug:
447 * should have provided the rx buffer before setup() returned.
450 void *buf = req->buf + req->actual;
451 unsigned len = req->length - req->actual;
453 /* read the buffer */
454 count = musb_readb(regs, MUSB_COUNT0);
456 req->status = -EOVERFLOW;
459 musb_read_fifo(&musb->endpoints[0], count, buf);
460 req->actual += count;
461 csr = MUSB_CSR0_P_SVDRXPKTRDY;
462 if (count < 64 || req->actual == req->length) {
463 musb->ep0_state = MUSB_EP0_STAGE_STATUSIN;
464 csr |= MUSB_CSR0_P_DATAEND;
468 csr = MUSB_CSR0_P_SVDRXPKTRDY | MUSB_CSR0_P_SENDSTALL;
471 /* Completion handler may choose to stall, e.g. because the
472 * message just received holds invalid data.
476 musb_g_ep0_giveback(musb, req);
481 musb_ep_select(musb->mregs, 0);
482 musb_writew(regs, MUSB_CSR0, csr);
486 * transmitting to the host (IN), this code might be called from IRQ
487 * and from kernel thread.
489 * Context: caller holds controller lock
491 static void ep0_txstate(struct musb *musb)
493 void __iomem *regs = musb->control_ep->regs;
494 struct usb_request *request = next_ep0_request(musb);
495 u16 csr = MUSB_CSR0_TXPKTRDY;
501 DBG(2, "odd; csr0 %04x\n", musb_readw(regs, MUSB_CSR0));
506 fifo_src = (u8 *) request->buf + request->actual;
507 fifo_count = min((unsigned) MUSB_EP0_FIFOSIZE,
508 request->length - request->actual);
509 musb_write_fifo(&musb->endpoints[0], fifo_count, fifo_src);
510 request->actual += fifo_count;
512 /* update the flags */
513 if (fifo_count < MUSB_MAX_END0_PACKET
514 || (request->actual == request->length
515 && !request->zero)) {
516 musb->ep0_state = MUSB_EP0_STAGE_STATUSOUT;
517 csr |= MUSB_CSR0_P_DATAEND;
521 /* report completions as soon as the fifo's loaded; there's no
522 * win in waiting till this last packet gets acked. (other than
523 * very precise fault reporting, needed by USB TMC; possible with
524 * this hardware, but not usable from portable gadget drivers.)
528 musb_g_ep0_giveback(musb, request);
534 /* send it out, triggering a "txpktrdy cleared" irq */
535 musb_ep_select(musb->mregs, 0);
536 musb_writew(regs, MUSB_CSR0, csr);
540 * Read a SETUP packet (struct usb_ctrlrequest) from the hardware.
541 * Fields are left in USB byte-order.
543 * Context: caller holds controller lock.
546 musb_read_setup(struct musb *musb, struct usb_ctrlrequest *req)
548 struct usb_request *r;
549 void __iomem *regs = musb->control_ep->regs;
551 musb_read_fifo(&musb->endpoints[0], sizeof *req, (u8 *)req);
553 /* NOTE: earlier 2.6 versions changed setup packets to host
554 * order, but now USB packets always stay in USB byte order.
556 DBG(3, "SETUP req%02x.%02x v%04x i%04x l%d\n",
559 le16_to_cpu(req->wValue),
560 le16_to_cpu(req->wIndex),
561 le16_to_cpu(req->wLength));
563 /* clean up any leftover transfers */
564 r = next_ep0_request(musb);
566 musb_g_ep0_giveback(musb, r);
568 /* For zero-data requests we want to delay the STATUS stage to
569 * avoid SETUPEND errors. If we read data (OUT), delay accepting
570 * packets until there's a buffer to store them in.
572 * If we write data, the controller acts happier if we enable
573 * the TX FIFO right away, and give the controller a moment
576 musb->set_address = false;
577 musb->ackpend = MUSB_CSR0_P_SVDRXPKTRDY;
578 if (req->wLength == 0) {
579 if (req->bRequestType & USB_DIR_IN)
580 musb->ackpend |= MUSB_CSR0_TXPKTRDY;
581 musb->ep0_state = MUSB_EP0_STAGE_ACKWAIT;
582 } else if (req->bRequestType & USB_DIR_IN) {
583 musb->ep0_state = MUSB_EP0_STAGE_TX;
584 musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SVDRXPKTRDY);
585 while ((musb_readw(regs, MUSB_CSR0)
586 & MUSB_CSR0_RXPKTRDY) != 0)
590 musb->ep0_state = MUSB_EP0_STAGE_RX;
594 forward_to_driver(struct musb *musb, const struct usb_ctrlrequest *ctrlrequest)
595 __releases(musb->lock)
596 __acquires(musb->lock)
599 if (!musb->gadget_driver)
601 spin_unlock(&musb->lock);
602 retval = musb->gadget_driver->setup(&musb->g, ctrlrequest);
603 spin_lock(&musb->lock);
608 * Handle peripheral ep0 interrupt
610 * Context: irq handler; we won't re-enter the driver that way.
612 irqreturn_t musb_g_ep0_irq(struct musb *musb)
616 void __iomem *mbase = musb->mregs;
617 void __iomem *regs = musb->endpoints[0].regs;
618 irqreturn_t retval = IRQ_NONE;
620 musb_ep_select(mbase, 0); /* select ep0 */
621 csr = musb_readw(regs, MUSB_CSR0);
622 len = musb_readb(regs, MUSB_COUNT0);
624 DBG(4, "csr %04x, count %d, myaddr %d, ep0stage %s\n",
626 musb_readb(mbase, MUSB_FADDR),
627 decode_ep0stage(musb->ep0_state));
629 /* I sent a stall.. need to acknowledge it now.. */
630 if (csr & MUSB_CSR0_P_SENTSTALL) {
631 musb_writew(regs, MUSB_CSR0,
632 csr & ~MUSB_CSR0_P_SENTSTALL);
633 retval = IRQ_HANDLED;
634 musb->ep0_state = MUSB_EP0_STAGE_IDLE;
635 csr = musb_readw(regs, MUSB_CSR0);
638 /* request ended "early" */
639 if (csr & MUSB_CSR0_P_SETUPEND) {
640 musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SVDSETUPEND);
641 retval = IRQ_HANDLED;
642 /* Transition into the early status phase */
643 switch (musb->ep0_state) {
644 case MUSB_EP0_STAGE_TX:
645 musb->ep0_state = MUSB_EP0_STAGE_STATUSOUT;
647 case MUSB_EP0_STAGE_RX:
648 musb->ep0_state = MUSB_EP0_STAGE_STATUSIN;
651 ERR("SetupEnd came in a wrong ep0stage %s",
652 decode_ep0stage(musb->ep0_state));
654 csr = musb_readw(regs, MUSB_CSR0);
655 /* NOTE: request may need completion */
658 /* docs from Mentor only describe tx, rx, and idle/setup states.
659 * we need to handle nuances around status stages, and also the
660 * case where status and setup stages come back-to-back ...
662 switch (musb->ep0_state) {
664 case MUSB_EP0_STAGE_TX:
665 /* irq on clearing txpktrdy */
666 if ((csr & MUSB_CSR0_TXPKTRDY) == 0) {
668 retval = IRQ_HANDLED;
672 case MUSB_EP0_STAGE_RX:
673 /* irq on set rxpktrdy */
674 if (csr & MUSB_CSR0_RXPKTRDY) {
676 retval = IRQ_HANDLED;
680 case MUSB_EP0_STAGE_STATUSIN:
681 /* end of sequence #2 (OUT/RX state) or #3 (no data) */
683 /* update address (if needed) only @ the end of the
684 * status phase per usb spec, which also guarantees
685 * we get 10 msec to receive this irq... until this
686 * is done we won't see the next packet.
688 if (musb->set_address) {
689 musb->set_address = false;
690 musb_writeb(mbase, MUSB_FADDR, musb->address);
693 /* enter test mode if needed (exit by reset) */
694 else if (musb->test_mode) {
695 DBG(1, "entering TESTMODE\n");
697 if (MUSB_TEST_PACKET == musb->test_mode_nr)
698 musb_load_testpacket(musb);
700 musb_writeb(mbase, MUSB_TESTMODE,
705 case MUSB_EP0_STAGE_STATUSOUT:
706 /* end of sequence #1: write to host (TX state) */
708 struct usb_request *req;
710 req = next_ep0_request(musb);
712 musb_g_ep0_giveback(musb, req);
716 * In case when several interrupts can get coalesced,
717 * check to see if we've already received a SETUP packet...
719 if (csr & MUSB_CSR0_RXPKTRDY)
722 retval = IRQ_HANDLED;
723 musb->ep0_state = MUSB_EP0_STAGE_IDLE;
726 case MUSB_EP0_STAGE_IDLE:
728 * This state is typically (but not always) indiscernible
729 * from the status states since the corresponding interrupts
730 * tend to happen within too little period of time (with only
731 * a zero-length packet in between) and so get coalesced...
733 retval = IRQ_HANDLED;
734 musb->ep0_state = MUSB_EP0_STAGE_SETUP;
737 case MUSB_EP0_STAGE_SETUP:
739 if (csr & MUSB_CSR0_RXPKTRDY) {
740 struct usb_ctrlrequest setup;
744 ERR("SETUP packet len %d != 8 ?\n", len);
747 musb_read_setup(musb, &setup);
748 retval = IRQ_HANDLED;
750 /* sometimes the RESET won't be reported */
751 if (unlikely(musb->g.speed == USB_SPEED_UNKNOWN)) {
754 printk(KERN_NOTICE "%s: peripheral reset "
757 power = musb_readb(mbase, MUSB_POWER);
758 musb->g.speed = (power & MUSB_POWER_HSMODE)
759 ? USB_SPEED_HIGH : USB_SPEED_FULL;
763 switch (musb->ep0_state) {
765 /* sequence #3 (no data stage), includes requests
766 * we can't forward (notably SET_ADDRESS and the
767 * device/endpoint feature set/clear operations)
768 * plus SET_CONFIGURATION and others we must
770 case MUSB_EP0_STAGE_ACKWAIT:
771 handled = service_zero_data_request(
774 /* status stage might be immediate */
776 musb->ackpend |= MUSB_CSR0_P_DATAEND;
778 MUSB_EP0_STAGE_STATUSIN;
782 /* sequence #1 (IN to host), includes GET_STATUS
783 * requests that we can't forward, GET_DESCRIPTOR
784 * and others that we must
786 case MUSB_EP0_STAGE_TX:
787 handled = service_in_request(musb, &setup);
789 musb->ackpend = MUSB_CSR0_TXPKTRDY
790 | MUSB_CSR0_P_DATAEND;
792 MUSB_EP0_STAGE_STATUSOUT;
796 /* sequence #2 (OUT from host), always forward */
797 default: /* MUSB_EP0_STAGE_RX */
801 DBG(3, "handled %d, csr %04x, ep0stage %s\n",
803 decode_ep0stage(musb->ep0_state));
805 /* unless we need to delegate this to the gadget
806 * driver, we know how to wrap this up: csr0 has
807 * not yet been written.
811 else if (handled > 0)
814 handled = forward_to_driver(musb, &setup);
816 musb_ep_select(mbase, 0);
818 DBG(3, "stall (%d)\n", handled);
819 musb->ackpend |= MUSB_CSR0_P_SENDSTALL;
820 musb->ep0_state = MUSB_EP0_STAGE_IDLE;
822 musb_writew(regs, MUSB_CSR0,
829 case MUSB_EP0_STAGE_ACKWAIT:
830 /* This should not happen. But happens with tusb6010 with
831 * g_file_storage and high speed. Do nothing.
833 retval = IRQ_HANDLED;
839 musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SENDSTALL);
840 musb->ep0_state = MUSB_EP0_STAGE_IDLE;
849 musb_g_ep0_enable(struct usb_ep *ep, const struct usb_endpoint_descriptor *desc)
855 static int musb_g_ep0_disable(struct usb_ep *e)
862 musb_g_ep0_queue(struct usb_ep *e, struct usb_request *r, gfp_t gfp_flags)
865 struct musb_request *req;
868 unsigned long lockflags;
876 regs = musb->control_ep->regs;
878 req = to_musb_request(r);
880 req->request.actual = 0;
881 req->request.status = -EINPROGRESS;
884 spin_lock_irqsave(&musb->lock, lockflags);
886 if (!list_empty(&ep->req_list)) {
891 switch (musb->ep0_state) {
892 case MUSB_EP0_STAGE_RX: /* control-OUT data */
893 case MUSB_EP0_STAGE_TX: /* control-IN data */
894 case MUSB_EP0_STAGE_ACKWAIT: /* zero-length data */
898 DBG(1, "ep0 request queued in state %d\n",
904 /* add request to the list */
905 list_add_tail(&(req->request.list), &(ep->req_list));
907 DBG(3, "queue to %s (%s), length=%d\n",
908 ep->name, ep->is_in ? "IN/TX" : "OUT/RX",
909 req->request.length);
911 musb_ep_select(musb->mregs, 0);
913 /* sequence #1, IN ... start writing the data */
914 if (musb->ep0_state == MUSB_EP0_STAGE_TX)
917 /* sequence #3, no-data ... issue IN status */
918 else if (musb->ep0_state == MUSB_EP0_STAGE_ACKWAIT) {
919 if (req->request.length)
922 musb->ep0_state = MUSB_EP0_STAGE_STATUSIN;
923 musb_writew(regs, MUSB_CSR0,
924 musb->ackpend | MUSB_CSR0_P_DATAEND);
926 musb_g_ep0_giveback(ep->musb, r);
929 /* else for sequence #2 (OUT), caller provides a buffer
930 * before the next packet arrives. deferred responses
931 * (after SETUP is acked) are racey.
933 } else if (musb->ackpend) {
934 musb_writew(regs, MUSB_CSR0, musb->ackpend);
939 spin_unlock_irqrestore(&musb->lock, lockflags);
943 static int musb_g_ep0_dequeue(struct usb_ep *ep, struct usb_request *req)
945 /* we just won't support this */
949 static int musb_g_ep0_halt(struct usb_ep *e, int value)
953 void __iomem *base, *regs;
964 regs = musb->control_ep->regs;
967 spin_lock_irqsave(&musb->lock, flags);
969 if (!list_empty(&ep->req_list)) {
974 musb_ep_select(base, 0);
977 switch (musb->ep0_state) {
979 /* Stalls are usually issued after parsing SETUP packet, either
980 * directly in irq context from setup() or else later.
982 case MUSB_EP0_STAGE_TX: /* control-IN data */
983 case MUSB_EP0_STAGE_ACKWAIT: /* STALL for zero-length data */
984 case MUSB_EP0_STAGE_RX: /* control-OUT data */
985 csr = musb_readw(regs, MUSB_CSR0);
988 /* It's also OK to issue stalls during callbacks when a non-empty
989 * DATA stage buffer has been read (or even written).
991 case MUSB_EP0_STAGE_STATUSIN: /* control-OUT status */
992 case MUSB_EP0_STAGE_STATUSOUT: /* control-IN status */
994 csr |= MUSB_CSR0_P_SENDSTALL;
995 musb_writew(regs, MUSB_CSR0, csr);
996 musb->ep0_state = MUSB_EP0_STAGE_IDLE;
1000 DBG(1, "ep0 can't halt in state %d\n", musb->ep0_state);
1005 spin_unlock_irqrestore(&musb->lock, flags);
1009 const struct usb_ep_ops musb_g_ep0_ops = {
1010 .enable = musb_g_ep0_enable,
1011 .disable = musb_g_ep0_disable,
1012 .alloc_request = musb_alloc_request,
1013 .free_request = musb_free_request,
1014 .queue = musb_g_ep0_queue,
1015 .dequeue = musb_g_ep0_dequeue,
1016 .set_halt = musb_g_ep0_halt,