musb_host.c revision 5d67a851bca63d30cde0474bfc4fc4f03db1a1b8
1/*
2 * MUSB OTG driver host support
3 *
4 * Copyright 2005 Mentor Graphics Corporation
5 * Copyright (C) 2005-2006 by Texas Instruments
6 * Copyright (C) 2006-2007 Nokia Corporation
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 *
22 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
25 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
28 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
29 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 *
33 */
34
35#include <linux/module.h>
36#include <linux/kernel.h>
37#include <linux/delay.h>
38#include <linux/sched.h>
39#include <linux/slab.h>
40#include <linux/errno.h>
41#include <linux/init.h>
42#include <linux/list.h>
43
44#include "musb_core.h"
45#include "musb_host.h"
46
47
48/* MUSB HOST status 22-mar-2006
49 *
50 * - There's still lots of partial code duplication for fault paths, so
51 *   they aren't handled as consistently as they need to be.
52 *
53 * - PIO mostly behaved when last tested.
54 *     + including ep0, with all usbtest cases 9, 10
55 *     + usbtest 14 (ep0out) doesn't seem to run at all
56 *     + double buffered OUT/TX endpoints saw stalls(!) with certain usbtest
57 *       configurations, but otherwise double buffering passes basic tests.
58 *     + for 2.6.N, for N > ~10, needs API changes for hcd framework.
59 *
60 * - DMA (CPPI) ... partially behaves, not currently recommended
61 *     + about 1/15 the speed of typical EHCI implementations (PCI)
62 *     + RX, all too often reqpkt seems to misbehave after tx
63 *     + TX, no known issues (other than evident silicon issue)
64 *
65 * - DMA (Mentor/OMAP) ...has at least toggle update problems
66 *
67 * - Still no traffic scheduling code to make NAKing for bulk or control
68 *   transfers unable to starve other requests; or to make efficient use
69 *   of hardware with periodic transfers.  (Note that network drivers
70 *   commonly post bulk reads that stay pending for a long time; these
71 *   would make very visible trouble.)
72 *
73 * - Not tested with HNP, but some SRP paths seem to behave.
74 *
75 * NOTE 24-August-2006:
76 *
77 * - Bulk traffic finally uses both sides of hardware ep1, freeing up an
78 *   extra endpoint for periodic use enabling hub + keybd + mouse.  That
79 *   mostly works, except that with "usbnet" it's easy to trigger cases
80 *   with "ping" where RX loses.  (a) ping to davinci, even "ping -f",
81 *   fine; but (b) ping _from_ davinci, even "ping -c 1", ICMP RX loses
82 *   although ARP RX wins.  (That test was done with a full speed link.)
83 */
84
85
86/*
87 * NOTE on endpoint usage:
88 *
89 * CONTROL transfers all go through ep0.  BULK ones go through dedicated IN
90 * and OUT endpoints ... hardware is dedicated for those "async" queue(s).
91 *
92 * (Yes, bulk _could_ use more of the endpoints than that, and would even
93 * benefit from it ... one remote device may easily be NAKing while others
94 * need to perform transfers in that same direction.  The same thing could
95 * be done in software though, assuming dma cooperates.)
96 *
97 * INTERUPPT and ISOCHRONOUS transfers are scheduled to the other endpoints.
98 * So far that scheduling is both dumb and optimistic:  the endpoint will be
99 * "claimed" until its software queue is no longer refilled.  No multiplexing
100 * of transfers between endpoints, or anything clever.
101 */
102
103
104static void musb_ep_program(struct musb *musb, u8 epnum,
105			struct urb *urb, unsigned int nOut,
106			u8 *buf, u32 len);
107
108/*
109 * Clear TX fifo. Needed to avoid BABBLE errors.
110 */
111static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
112{
113	void __iomem	*epio = ep->regs;
114	u16		csr;
115	u16		lastcsr = 0;
116	int		retries = 1000;
117
118	csr = musb_readw(epio, MUSB_TXCSR);
119	while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
120		if (csr != lastcsr)
121			DBG(3, "Host TX FIFONOTEMPTY csr: %02x\n", csr);
122		lastcsr = csr;
123		csr |= MUSB_TXCSR_FLUSHFIFO;
124		musb_writew(epio, MUSB_TXCSR, csr);
125		csr = musb_readw(epio, MUSB_TXCSR);
126		if (WARN(retries-- < 1,
127				"Could not flush host TX%d fifo: csr: %04x\n",
128				ep->epnum, csr))
129			return;
130		mdelay(1);
131	}
132}
133
134/*
135 * Start transmit. Caller is responsible for locking shared resources.
136 * musb must be locked.
137 */
138static inline void musb_h_tx_start(struct musb_hw_ep *ep)
139{
140	u16	txcsr;
141
142	/* NOTE: no locks here; caller should lock and select EP */
143	if (ep->epnum) {
144		txcsr = musb_readw(ep->regs, MUSB_TXCSR);
145		txcsr |= MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_H_WZC_BITS;
146		musb_writew(ep->regs, MUSB_TXCSR, txcsr);
147	} else {
148		txcsr = MUSB_CSR0_H_SETUPPKT | MUSB_CSR0_TXPKTRDY;
149		musb_writew(ep->regs, MUSB_CSR0, txcsr);
150	}
151
152}
153
154static inline void cppi_host_txdma_start(struct musb_hw_ep *ep)
155{
156	u16	txcsr;
157
158	/* NOTE: no locks here; caller should lock and select EP */
159	txcsr = musb_readw(ep->regs, MUSB_TXCSR);
160	txcsr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_H_WZC_BITS;
161	musb_writew(ep->regs, MUSB_TXCSR, txcsr);
162}
163
164/*
165 * Start the URB at the front of an endpoint's queue
166 * end must be claimed from the caller.
167 *
168 * Context: controller locked, irqs blocked
169 */
170static void
171musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
172{
173	u16			frame;
174	u32			len;
175	void			*buf;
176	void __iomem		*mbase =  musb->mregs;
177	struct urb		*urb = next_urb(qh);
178	struct musb_hw_ep	*hw_ep = qh->hw_ep;
179	unsigned		pipe = urb->pipe;
180	u8			address = usb_pipedevice(pipe);
181	int			epnum = hw_ep->epnum;
182
183	/* initialize software qh state */
184	qh->offset = 0;
185	qh->segsize = 0;
186
187	/* gather right source of data */
188	switch (qh->type) {
189	case USB_ENDPOINT_XFER_CONTROL:
190		/* control transfers always start with SETUP */
191		is_in = 0;
192		hw_ep->out_qh = qh;
193		musb->ep0_stage = MUSB_EP0_START;
194		buf = urb->setup_packet;
195		len = 8;
196		break;
197	case USB_ENDPOINT_XFER_ISOC:
198		qh->iso_idx = 0;
199		qh->frame = 0;
200		buf = urb->transfer_buffer + urb->iso_frame_desc[0].offset;
201		len = urb->iso_frame_desc[0].length;
202		break;
203	default:		/* bulk, interrupt */
204		buf = urb->transfer_buffer;
205		len = urb->transfer_buffer_length;
206	}
207
208	DBG(4, "qh %p urb %p dev%d ep%d%s%s, hw_ep %d, %p/%d\n",
209			qh, urb, address, qh->epnum,
210			is_in ? "in" : "out",
211			({char *s; switch (qh->type) {
212			case USB_ENDPOINT_XFER_CONTROL:	s = ""; break;
213			case USB_ENDPOINT_XFER_BULK:	s = "-bulk"; break;
214			case USB_ENDPOINT_XFER_ISOC:	s = "-iso"; break;
215			default:			s = "-intr"; break;
216			}; s; }),
217			epnum, buf, len);
218
219	/* Configure endpoint */
220	if (is_in || hw_ep->is_shared_fifo)
221		hw_ep->in_qh = qh;
222	else
223		hw_ep->out_qh = qh;
224	musb_ep_program(musb, epnum, urb, !is_in, buf, len);
225
226	/* transmit may have more work: start it when it is time */
227	if (is_in)
228		return;
229
230	/* determine if the time is right for a periodic transfer */
231	switch (qh->type) {
232	case USB_ENDPOINT_XFER_ISOC:
233	case USB_ENDPOINT_XFER_INT:
234		DBG(3, "check whether there's still time for periodic Tx\n");
235		qh->iso_idx = 0;
236		frame = musb_readw(mbase, MUSB_FRAME);
237		/* FIXME this doesn't implement that scheduling policy ...
238		 * or handle framecounter wrapping
239		 */
240		if ((urb->transfer_flags & URB_ISO_ASAP)
241				|| (frame >= urb->start_frame)) {
242			/* REVISIT the SOF irq handler shouldn't duplicate
243			 * this code; and we don't init urb->start_frame...
244			 */
245			qh->frame = 0;
246			goto start;
247		} else {
248			qh->frame = urb->start_frame;
249			/* enable SOF interrupt so we can count down */
250			DBG(1, "SOF for %d\n", epnum);
251#if 1 /* ifndef	CONFIG_ARCH_DAVINCI */
252			musb_writeb(mbase, MUSB_INTRUSBE, 0xff);
253#endif
254		}
255		break;
256	default:
257start:
258		DBG(4, "Start TX%d %s\n", epnum,
259			hw_ep->tx_channel ? "dma" : "pio");
260
261		if (!hw_ep->tx_channel)
262			musb_h_tx_start(hw_ep);
263		else if (is_cppi_enabled() || tusb_dma_omap())
264			cppi_host_txdma_start(hw_ep);
265	}
266}
267
268/* caller owns controller lock, irqs are blocked */
269static void
270__musb_giveback(struct musb *musb, struct urb *urb, int status)
271__releases(musb->lock)
272__acquires(musb->lock)
273{
274	DBG(({ int level; switch (status) {
275				case 0:
276					level = 4;
277					break;
278				/* common/boring faults */
279				case -EREMOTEIO:
280				case -ESHUTDOWN:
281				case -ECONNRESET:
282				case -EPIPE:
283					level = 3;
284					break;
285				default:
286					level = 2;
287					break;
288				}; level; }),
289			"complete %p %pF (%d), dev%d ep%d%s, %d/%d\n",
290			urb, urb->complete, status,
291			usb_pipedevice(urb->pipe),
292			usb_pipeendpoint(urb->pipe),
293			usb_pipein(urb->pipe) ? "in" : "out",
294			urb->actual_length, urb->transfer_buffer_length
295			);
296
297	usb_hcd_unlink_urb_from_ep(musb_to_hcd(musb), urb);
298	spin_unlock(&musb->lock);
299	usb_hcd_giveback_urb(musb_to_hcd(musb), urb, status);
300	spin_lock(&musb->lock);
301}
302
303/* for bulk/interrupt endpoints only */
304static inline void
305musb_save_toggle(struct musb_hw_ep *ep, int is_in, struct urb *urb)
306{
307	struct usb_device	*udev = urb->dev;
308	u16			csr;
309	void __iomem		*epio = ep->regs;
310	struct musb_qh		*qh;
311
312	/* FIXME:  the current Mentor DMA code seems to have
313	 * problems getting toggle correct.
314	 */
315
316	if (is_in || ep->is_shared_fifo)
317		qh = ep->in_qh;
318	else
319		qh = ep->out_qh;
320
321	if (!is_in) {
322		csr = musb_readw(epio, MUSB_TXCSR);
323		usb_settoggle(udev, qh->epnum, 1,
324			(csr & MUSB_TXCSR_H_DATATOGGLE)
325				? 1 : 0);
326	} else {
327		csr = musb_readw(epio, MUSB_RXCSR);
328		usb_settoggle(udev, qh->epnum, 0,
329			(csr & MUSB_RXCSR_H_DATATOGGLE)
330				? 1 : 0);
331	}
332}
333
334/* caller owns controller lock, irqs are blocked */
335static struct musb_qh *
336musb_giveback(struct musb_qh *qh, struct urb *urb, int status)
337{
338	struct musb_hw_ep	*ep = qh->hw_ep;
339	struct musb		*musb = ep->musb;
340	int			is_in = usb_pipein(urb->pipe);
341	int			ready = qh->is_ready;
342
343	/* save toggle eagerly, for paranoia */
344	switch (qh->type) {
345	case USB_ENDPOINT_XFER_BULK:
346	case USB_ENDPOINT_XFER_INT:
347		musb_save_toggle(ep, is_in, urb);
348		break;
349	case USB_ENDPOINT_XFER_ISOC:
350		if (status == 0 && urb->error_count)
351			status = -EXDEV;
352		break;
353	}
354
355	qh->is_ready = 0;
356	__musb_giveback(musb, urb, status);
357	qh->is_ready = ready;
358
359	/* reclaim resources (and bandwidth) ASAP; deschedule it, and
360	 * invalidate qh as soon as list_empty(&hep->urb_list)
361	 */
362	if (list_empty(&qh->hep->urb_list)) {
363		struct list_head	*head;
364
365		if (is_in)
366			ep->rx_reinit = 1;
367		else
368			ep->tx_reinit = 1;
369
370		/* clobber old pointers to this qh */
371		if (is_in || ep->is_shared_fifo)
372			ep->in_qh = NULL;
373		else
374			ep->out_qh = NULL;
375		qh->hep->hcpriv = NULL;
376
377		switch (qh->type) {
378
379		case USB_ENDPOINT_XFER_CONTROL:
380		case USB_ENDPOINT_XFER_BULK:
381			/* fifo policy for these lists, except that NAKing
382			 * should rotate a qh to the end (for fairness).
383			 */
384			if (qh->mux == 1) {
385				head = qh->ring.prev;
386				list_del(&qh->ring);
387				kfree(qh);
388				qh = first_qh(head);
389				break;
390			}
391
392		case USB_ENDPOINT_XFER_ISOC:
393		case USB_ENDPOINT_XFER_INT:
394			/* this is where periodic bandwidth should be
395			 * de-allocated if it's tracked and allocated;
396			 * and where we'd update the schedule tree...
397			 */
398			kfree(qh);
399			qh = NULL;
400			break;
401		}
402	}
403	return qh;
404}
405
406/*
407 * Advance this hardware endpoint's queue, completing the specified urb and
408 * advancing to either the next urb queued to that qh, or else invalidating
409 * that qh and advancing to the next qh scheduled after the current one.
410 *
411 * Context: caller owns controller lock, irqs are blocked
412 */
413static void
414musb_advance_schedule(struct musb *musb, struct urb *urb,
415		struct musb_hw_ep *hw_ep, int is_in)
416{
417	struct musb_qh	*qh;
418
419	if (is_in || hw_ep->is_shared_fifo)
420		qh = hw_ep->in_qh;
421	else
422		qh = hw_ep->out_qh;
423
424	if (urb->status == -EINPROGRESS)
425		qh = musb_giveback(qh, urb, 0);
426	else
427		qh = musb_giveback(qh, urb, urb->status);
428
429	if (qh != NULL && qh->is_ready) {
430		DBG(4, "... next ep%d %cX urb %p\n",
431				hw_ep->epnum, is_in ? 'R' : 'T',
432				next_urb(qh));
433		musb_start_urb(musb, is_in, qh);
434	}
435}
436
437static u16 musb_h_flush_rxfifo(struct musb_hw_ep *hw_ep, u16 csr)
438{
439	/* we don't want fifo to fill itself again;
440	 * ignore dma (various models),
441	 * leave toggle alone (may not have been saved yet)
442	 */
443	csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_RXPKTRDY;
444	csr &= ~(MUSB_RXCSR_H_REQPKT
445		| MUSB_RXCSR_H_AUTOREQ
446		| MUSB_RXCSR_AUTOCLEAR);
447
448	/* write 2x to allow double buffering */
449	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
450	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
451
452	/* flush writebuffer */
453	return musb_readw(hw_ep->regs, MUSB_RXCSR);
454}
455
456/*
457 * PIO RX for a packet (or part of it).
458 */
459static bool
460musb_host_packet_rx(struct musb *musb, struct urb *urb, u8 epnum, u8 iso_err)
461{
462	u16			rx_count;
463	u8			*buf;
464	u16			csr;
465	bool			done = false;
466	u32			length;
467	int			do_flush = 0;
468	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
469	void __iomem		*epio = hw_ep->regs;
470	struct musb_qh		*qh = hw_ep->in_qh;
471	int			pipe = urb->pipe;
472	void			*buffer = urb->transfer_buffer;
473
474	/* musb_ep_select(mbase, epnum); */
475	rx_count = musb_readw(epio, MUSB_RXCOUNT);
476	DBG(3, "RX%d count %d, buffer %p len %d/%d\n", epnum, rx_count,
477			urb->transfer_buffer, qh->offset,
478			urb->transfer_buffer_length);
479
480	/* unload FIFO */
481	if (usb_pipeisoc(pipe)) {
482		int					status = 0;
483		struct usb_iso_packet_descriptor	*d;
484
485		if (iso_err) {
486			status = -EILSEQ;
487			urb->error_count++;
488		}
489
490		d = urb->iso_frame_desc + qh->iso_idx;
491		buf = buffer + d->offset;
492		length = d->length;
493		if (rx_count > length) {
494			if (status == 0) {
495				status = -EOVERFLOW;
496				urb->error_count++;
497			}
498			DBG(2, "** OVERFLOW %d into %d\n", rx_count, length);
499			do_flush = 1;
500		} else
501			length = rx_count;
502		urb->actual_length += length;
503		d->actual_length = length;
504
505		d->status = status;
506
507		/* see if we are done */
508		done = (++qh->iso_idx >= urb->number_of_packets);
509	} else {
510		/* non-isoch */
511		buf = buffer + qh->offset;
512		length = urb->transfer_buffer_length - qh->offset;
513		if (rx_count > length) {
514			if (urb->status == -EINPROGRESS)
515				urb->status = -EOVERFLOW;
516			DBG(2, "** OVERFLOW %d into %d\n", rx_count, length);
517			do_flush = 1;
518		} else
519			length = rx_count;
520		urb->actual_length += length;
521		qh->offset += length;
522
523		/* see if we are done */
524		done = (urb->actual_length == urb->transfer_buffer_length)
525			|| (rx_count < qh->maxpacket)
526			|| (urb->status != -EINPROGRESS);
527		if (done
528				&& (urb->status == -EINPROGRESS)
529				&& (urb->transfer_flags & URB_SHORT_NOT_OK)
530				&& (urb->actual_length
531					< urb->transfer_buffer_length))
532			urb->status = -EREMOTEIO;
533	}
534
535	musb_read_fifo(hw_ep, length, buf);
536
537	csr = musb_readw(epio, MUSB_RXCSR);
538	csr |= MUSB_RXCSR_H_WZC_BITS;
539	if (unlikely(do_flush))
540		musb_h_flush_rxfifo(hw_ep, csr);
541	else {
542		/* REVISIT this assumes AUTOCLEAR is never set */
543		csr &= ~(MUSB_RXCSR_RXPKTRDY | MUSB_RXCSR_H_REQPKT);
544		if (!done)
545			csr |= MUSB_RXCSR_H_REQPKT;
546		musb_writew(epio, MUSB_RXCSR, csr);
547	}
548
549	return done;
550}
551
552/* we don't always need to reinit a given side of an endpoint...
553 * when we do, use tx/rx reinit routine and then construct a new CSR
554 * to address data toggle, NYET, and DMA or PIO.
555 *
556 * it's possible that driver bugs (especially for DMA) or aborting a
557 * transfer might have left the endpoint busier than it should be.
558 * the busy/not-empty tests are basically paranoia.
559 */
560static void
561musb_rx_reinit(struct musb *musb, struct musb_qh *qh, struct musb_hw_ep *ep)
562{
563	u16	csr;
564
565	/* NOTE:  we know the "rx" fifo reinit never triggers for ep0.
566	 * That always uses tx_reinit since ep0 repurposes TX register
567	 * offsets; the initial SETUP packet is also a kind of OUT.
568	 */
569
570	/* if programmed for Tx, put it in RX mode */
571	if (ep->is_shared_fifo) {
572		csr = musb_readw(ep->regs, MUSB_TXCSR);
573		if (csr & MUSB_TXCSR_MODE) {
574			musb_h_tx_flush_fifo(ep);
575			musb_writew(ep->regs, MUSB_TXCSR,
576					MUSB_TXCSR_FRCDATATOG);
577		}
578		/* clear mode (and everything else) to enable Rx */
579		musb_writew(ep->regs, MUSB_TXCSR, 0);
580
581	/* scrub all previous state, clearing toggle */
582	} else {
583		csr = musb_readw(ep->regs, MUSB_RXCSR);
584		if (csr & MUSB_RXCSR_RXPKTRDY)
585			WARNING("rx%d, packet/%d ready?\n", ep->epnum,
586				musb_readw(ep->regs, MUSB_RXCOUNT));
587
588		musb_h_flush_rxfifo(ep, MUSB_RXCSR_CLRDATATOG);
589	}
590
591	/* target addr and (for multipoint) hub addr/port */
592	if (musb->is_multipoint) {
593		musb_write_rxfunaddr(ep->target_regs, qh->addr_reg);
594		musb_write_rxhubaddr(ep->target_regs, qh->h_addr_reg);
595		musb_write_rxhubport(ep->target_regs, qh->h_port_reg);
596
597	} else
598		musb_writeb(musb->mregs, MUSB_FADDR, qh->addr_reg);
599
600	/* protocol/endpoint, interval/NAKlimit, i/o size */
601	musb_writeb(ep->regs, MUSB_RXTYPE, qh->type_reg);
602	musb_writeb(ep->regs, MUSB_RXINTERVAL, qh->intv_reg);
603	/* NOTE: bulk combining rewrites high bits of maxpacket */
604	musb_writew(ep->regs, MUSB_RXMAXP, qh->maxpacket);
605
606	ep->rx_reinit = 0;
607}
608
609
610/*
611 * Program an HDRC endpoint as per the given URB
612 * Context: irqs blocked, controller lock held
613 */
614static void musb_ep_program(struct musb *musb, u8 epnum,
615			struct urb *urb, unsigned int is_out,
616			u8 *buf, u32 len)
617{
618	struct dma_controller	*dma_controller;
619	struct dma_channel	*dma_channel;
620	u8			dma_ok;
621	void __iomem		*mbase = musb->mregs;
622	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
623	void __iomem		*epio = hw_ep->regs;
624	struct musb_qh		*qh;
625	u16			packet_sz;
626
627	if (!is_out || hw_ep->is_shared_fifo)
628		qh = hw_ep->in_qh;
629	else
630		qh = hw_ep->out_qh;
631
632	packet_sz = qh->maxpacket;
633
634	DBG(3, "%s hw%d urb %p spd%d dev%d ep%d%s "
635				"h_addr%02x h_port%02x bytes %d\n",
636			is_out ? "-->" : "<--",
637			epnum, urb, urb->dev->speed,
638			qh->addr_reg, qh->epnum, is_out ? "out" : "in",
639			qh->h_addr_reg, qh->h_port_reg,
640			len);
641
642	musb_ep_select(mbase, epnum);
643
644	/* candidate for DMA? */
645	dma_controller = musb->dma_controller;
646	if (is_dma_capable() && epnum && dma_controller) {
647		dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel;
648		if (!dma_channel) {
649			dma_channel = dma_controller->channel_alloc(
650					dma_controller, hw_ep, is_out);
651			if (is_out)
652				hw_ep->tx_channel = dma_channel;
653			else
654				hw_ep->rx_channel = dma_channel;
655		}
656	} else
657		dma_channel = NULL;
658
659	/* make sure we clear DMAEnab, autoSet bits from previous run */
660
661	/* OUT/transmit/EP0 or IN/receive? */
662	if (is_out) {
663		u16	csr;
664		u16	int_txe;
665		u16	load_count;
666
667		csr = musb_readw(epio, MUSB_TXCSR);
668
669		/* disable interrupt in case we flush */
670		int_txe = musb_readw(mbase, MUSB_INTRTXE);
671		musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
672
673		/* general endpoint setup */
674		if (epnum) {
675			/* ASSERT:  TXCSR_DMAENAB was already cleared */
676
677			/* flush all old state, set default */
678			musb_h_tx_flush_fifo(hw_ep);
679			csr &= ~(MUSB_TXCSR_H_NAKTIMEOUT
680					| MUSB_TXCSR_DMAMODE
681					| MUSB_TXCSR_FRCDATATOG
682					| MUSB_TXCSR_H_RXSTALL
683					| MUSB_TXCSR_H_ERROR
684					| MUSB_TXCSR_TXPKTRDY
685					);
686			csr |= MUSB_TXCSR_MODE;
687
688			if (usb_gettoggle(urb->dev,
689					qh->epnum, 1))
690				csr |= MUSB_TXCSR_H_WR_DATATOGGLE
691					| MUSB_TXCSR_H_DATATOGGLE;
692			else
693				csr |= MUSB_TXCSR_CLRDATATOG;
694
695			/* twice in case of double packet buffering */
696			musb_writew(epio, MUSB_TXCSR, csr);
697			/* REVISIT may need to clear FLUSHFIFO ... */
698			musb_writew(epio, MUSB_TXCSR, csr);
699			csr = musb_readw(epio, MUSB_TXCSR);
700		} else {
701			/* endpoint 0: just flush */
702			musb_writew(epio, MUSB_CSR0,
703				csr | MUSB_CSR0_FLUSHFIFO);
704			musb_writew(epio, MUSB_CSR0,
705				csr | MUSB_CSR0_FLUSHFIFO);
706		}
707
708		/* target addr and (for multipoint) hub addr/port */
709		if (musb->is_multipoint) {
710			musb_write_txfunaddr(mbase, epnum, qh->addr_reg);
711			musb_write_txhubaddr(mbase, epnum, qh->h_addr_reg);
712			musb_write_txhubport(mbase, epnum, qh->h_port_reg);
713/* FIXME if !epnum, do the same for RX ... */
714		} else
715			musb_writeb(mbase, MUSB_FADDR, qh->addr_reg);
716
717		/* protocol/endpoint/interval/NAKlimit */
718		if (epnum) {
719			musb_writeb(epio, MUSB_TXTYPE, qh->type_reg);
720			if (can_bulk_split(musb, qh->type))
721				musb_writew(epio, MUSB_TXMAXP,
722					packet_sz
723					| ((hw_ep->max_packet_sz_tx /
724						packet_sz) - 1) << 11);
725			else
726				musb_writew(epio, MUSB_TXMAXP,
727					packet_sz);
728			musb_writeb(epio, MUSB_TXINTERVAL, qh->intv_reg);
729		} else {
730			musb_writeb(epio, MUSB_NAKLIMIT0, qh->intv_reg);
731			if (musb->is_multipoint)
732				musb_writeb(epio, MUSB_TYPE0,
733						qh->type_reg);
734		}
735
736		if (can_bulk_split(musb, qh->type))
737			load_count = min((u32) hw_ep->max_packet_sz_tx,
738						len);
739		else
740			load_count = min((u32) packet_sz, len);
741
742#ifdef CONFIG_USB_INVENTRA_DMA
743		if (dma_channel) {
744
745			/* clear previous state */
746			csr = musb_readw(epio, MUSB_TXCSR);
747			csr &= ~(MUSB_TXCSR_AUTOSET
748				| MUSB_TXCSR_DMAMODE
749				| MUSB_TXCSR_DMAENAB);
750			csr |= MUSB_TXCSR_MODE;
751			musb_writew(epio, MUSB_TXCSR,
752				csr | MUSB_TXCSR_MODE);
753
754			qh->segsize = min(len, dma_channel->max_len);
755
756			if (qh->segsize <= packet_sz)
757				dma_channel->desired_mode = 0;
758			else
759				dma_channel->desired_mode = 1;
760
761
762			if (dma_channel->desired_mode == 0) {
763				csr &= ~(MUSB_TXCSR_AUTOSET
764					| MUSB_TXCSR_DMAMODE);
765				csr |= (MUSB_TXCSR_DMAENAB);
766					/* against programming guide */
767			} else
768				csr |= (MUSB_TXCSR_AUTOSET
769					| MUSB_TXCSR_DMAENAB
770					| MUSB_TXCSR_DMAMODE);
771
772			musb_writew(epio, MUSB_TXCSR, csr);
773
774			dma_ok = dma_controller->channel_program(
775					dma_channel, packet_sz,
776					dma_channel->desired_mode,
777					urb->transfer_dma,
778					qh->segsize);
779			if (dma_ok) {
780				load_count = 0;
781			} else {
782				dma_controller->channel_release(dma_channel);
783				if (is_out)
784					hw_ep->tx_channel = NULL;
785				else
786					hw_ep->rx_channel = NULL;
787				dma_channel = NULL;
788			}
789		}
790#endif
791
792		/* candidate for DMA */
793		if ((is_cppi_enabled() || tusb_dma_omap()) && dma_channel) {
794
795			/* program endpoint CSRs first, then setup DMA.
796			 * assume CPPI setup succeeds.
797			 * defer enabling dma.
798			 */
799			csr = musb_readw(epio, MUSB_TXCSR);
800			csr &= ~(MUSB_TXCSR_AUTOSET
801					| MUSB_TXCSR_DMAMODE
802					| MUSB_TXCSR_DMAENAB);
803			csr |= MUSB_TXCSR_MODE;
804			musb_writew(epio, MUSB_TXCSR,
805				csr | MUSB_TXCSR_MODE);
806
807			dma_channel->actual_len = 0L;
808			qh->segsize = len;
809
810			/* TX uses "rndis" mode automatically, but needs help
811			 * to identify the zero-length-final-packet case.
812			 */
813			dma_ok = dma_controller->channel_program(
814					dma_channel, packet_sz,
815					(urb->transfer_flags
816							& URB_ZERO_PACKET)
817						== URB_ZERO_PACKET,
818					urb->transfer_dma,
819					qh->segsize);
820			if (dma_ok) {
821				load_count = 0;
822			} else {
823				dma_controller->channel_release(dma_channel);
824				hw_ep->tx_channel = NULL;
825				dma_channel = NULL;
826
827				/* REVISIT there's an error path here that
828				 * needs handling:  can't do dma, but
829				 * there's no pio buffer address...
830				 */
831			}
832		}
833
834		if (load_count) {
835			/* ASSERT:  TXCSR_DMAENAB was already cleared */
836
837			/* PIO to load FIFO */
838			qh->segsize = load_count;
839			musb_write_fifo(hw_ep, load_count, buf);
840			csr = musb_readw(epio, MUSB_TXCSR);
841			csr &= ~(MUSB_TXCSR_DMAENAB
842				| MUSB_TXCSR_DMAMODE
843				| MUSB_TXCSR_AUTOSET);
844			/* write CSR */
845			csr |= MUSB_TXCSR_MODE;
846
847			if (epnum)
848				musb_writew(epio, MUSB_TXCSR, csr);
849		}
850
851		/* re-enable interrupt */
852		musb_writew(mbase, MUSB_INTRTXE, int_txe);
853
854	/* IN/receive */
855	} else {
856		u16	csr;
857
858		if (hw_ep->rx_reinit) {
859			musb_rx_reinit(musb, qh, hw_ep);
860
861			/* init new state: toggle and NYET, maybe DMA later */
862			if (usb_gettoggle(urb->dev, qh->epnum, 0))
863				csr = MUSB_RXCSR_H_WR_DATATOGGLE
864					| MUSB_RXCSR_H_DATATOGGLE;
865			else
866				csr = 0;
867			if (qh->type == USB_ENDPOINT_XFER_INT)
868				csr |= MUSB_RXCSR_DISNYET;
869
870		} else {
871			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
872
873			if (csr & (MUSB_RXCSR_RXPKTRDY
874					| MUSB_RXCSR_DMAENAB
875					| MUSB_RXCSR_H_REQPKT))
876				ERR("broken !rx_reinit, ep%d csr %04x\n",
877						hw_ep->epnum, csr);
878
879			/* scrub any stale state, leaving toggle alone */
880			csr &= MUSB_RXCSR_DISNYET;
881		}
882
883		/* kick things off */
884
885		if ((is_cppi_enabled() || tusb_dma_omap()) && dma_channel) {
886			/* candidate for DMA */
887			if (dma_channel) {
888				dma_channel->actual_len = 0L;
889				qh->segsize = len;
890
891				/* AUTOREQ is in a DMA register */
892				musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
893				csr = musb_readw(hw_ep->regs,
894						MUSB_RXCSR);
895
896				/* unless caller treats short rx transfers as
897				 * errors, we dare not queue multiple transfers.
898				 */
899				dma_ok = dma_controller->channel_program(
900						dma_channel, packet_sz,
901						!(urb->transfer_flags
902							& URB_SHORT_NOT_OK),
903						urb->transfer_dma,
904						qh->segsize);
905				if (!dma_ok) {
906					dma_controller->channel_release(
907							dma_channel);
908					hw_ep->rx_channel = NULL;
909					dma_channel = NULL;
910				} else
911					csr |= MUSB_RXCSR_DMAENAB;
912			}
913		}
914
915		csr |= MUSB_RXCSR_H_REQPKT;
916		DBG(7, "RXCSR%d := %04x\n", epnum, csr);
917		musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
918		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
919	}
920}
921
922
923/*
924 * Service the default endpoint (ep0) as host.
925 * Return true until it's time to start the status stage.
926 */
927static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
928{
929	bool			 more = false;
930	u8			*fifo_dest = NULL;
931	u16			fifo_count = 0;
932	struct musb_hw_ep	*hw_ep = musb->control_ep;
933	struct musb_qh		*qh = hw_ep->in_qh;
934	struct usb_ctrlrequest	*request;
935
936	switch (musb->ep0_stage) {
937	case MUSB_EP0_IN:
938		fifo_dest = urb->transfer_buffer + urb->actual_length;
939		fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
940				   urb->actual_length);
941		if (fifo_count < len)
942			urb->status = -EOVERFLOW;
943
944		musb_read_fifo(hw_ep, fifo_count, fifo_dest);
945
946		urb->actual_length += fifo_count;
947		if (len < qh->maxpacket) {
948			/* always terminate on short read; it's
949			 * rarely reported as an error.
950			 */
951		} else if (urb->actual_length <
952				urb->transfer_buffer_length)
953			more = true;
954		break;
955	case MUSB_EP0_START:
956		request = (struct usb_ctrlrequest *) urb->setup_packet;
957
958		if (!request->wLength) {
959			DBG(4, "start no-DATA\n");
960			break;
961		} else if (request->bRequestType & USB_DIR_IN) {
962			DBG(4, "start IN-DATA\n");
963			musb->ep0_stage = MUSB_EP0_IN;
964			more = true;
965			break;
966		} else {
967			DBG(4, "start OUT-DATA\n");
968			musb->ep0_stage = MUSB_EP0_OUT;
969			more = true;
970		}
971		/* FALLTHROUGH */
972	case MUSB_EP0_OUT:
973		fifo_count = min_t(size_t, qh->maxpacket,
974				   urb->transfer_buffer_length -
975				   urb->actual_length);
976		if (fifo_count) {
977			fifo_dest = (u8 *) (urb->transfer_buffer
978					+ urb->actual_length);
979			DBG(3, "Sending %d byte%s to ep0 fifo %p\n",
980					fifo_count,
981					(fifo_count == 1) ? "" : "s",
982					fifo_dest);
983			musb_write_fifo(hw_ep, fifo_count, fifo_dest);
984
985			urb->actual_length += fifo_count;
986			more = true;
987		}
988		break;
989	default:
990		ERR("bogus ep0 stage %d\n", musb->ep0_stage);
991		break;
992	}
993
994	return more;
995}
996
997/*
998 * Handle default endpoint interrupt as host. Only called in IRQ time
999 * from musb_interrupt().
1000 *
1001 * called with controller irqlocked
1002 */
1003irqreturn_t musb_h_ep0_irq(struct musb *musb)
1004{
1005	struct urb		*urb;
1006	u16			csr, len;
1007	int			status = 0;
1008	void __iomem		*mbase = musb->mregs;
1009	struct musb_hw_ep	*hw_ep = musb->control_ep;
1010	void __iomem		*epio = hw_ep->regs;
1011	struct musb_qh		*qh = hw_ep->in_qh;
1012	bool			complete = false;
1013	irqreturn_t		retval = IRQ_NONE;
1014
1015	/* ep0 only has one queue, "in" */
1016	urb = next_urb(qh);
1017
1018	musb_ep_select(mbase, 0);
1019	csr = musb_readw(epio, MUSB_CSR0);
1020	len = (csr & MUSB_CSR0_RXPKTRDY)
1021			? musb_readb(epio, MUSB_COUNT0)
1022			: 0;
1023
1024	DBG(4, "<== csr0 %04x, qh %p, count %d, urb %p, stage %d\n",
1025		csr, qh, len, urb, musb->ep0_stage);
1026
1027	/* if we just did status stage, we are done */
1028	if (MUSB_EP0_STATUS == musb->ep0_stage) {
1029		retval = IRQ_HANDLED;
1030		complete = true;
1031	}
1032
1033	/* prepare status */
1034	if (csr & MUSB_CSR0_H_RXSTALL) {
1035		DBG(6, "STALLING ENDPOINT\n");
1036		status = -EPIPE;
1037
1038	} else if (csr & MUSB_CSR0_H_ERROR) {
1039		DBG(2, "no response, csr0 %04x\n", csr);
1040		status = -EPROTO;
1041
1042	} else if (csr & MUSB_CSR0_H_NAKTIMEOUT) {
1043		DBG(2, "control NAK timeout\n");
1044
1045		/* NOTE:  this code path would be a good place to PAUSE a
1046		 * control transfer, if another one is queued, so that
1047		 * ep0 is more likely to stay busy.
1048		 *
1049		 * if (qh->ring.next != &musb->control), then
1050		 * we have a candidate... NAKing is *NOT* an error
1051		 */
1052		musb_writew(epio, MUSB_CSR0, 0);
1053		retval = IRQ_HANDLED;
1054	}
1055
1056	if (status) {
1057		DBG(6, "aborting\n");
1058		retval = IRQ_HANDLED;
1059		if (urb)
1060			urb->status = status;
1061		complete = true;
1062
1063		/* use the proper sequence to abort the transfer */
1064		if (csr & MUSB_CSR0_H_REQPKT) {
1065			csr &= ~MUSB_CSR0_H_REQPKT;
1066			musb_writew(epio, MUSB_CSR0, csr);
1067			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1068			musb_writew(epio, MUSB_CSR0, csr);
1069		} else {
1070			csr |= MUSB_CSR0_FLUSHFIFO;
1071			musb_writew(epio, MUSB_CSR0, csr);
1072			musb_writew(epio, MUSB_CSR0, csr);
1073			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1074			musb_writew(epio, MUSB_CSR0, csr);
1075		}
1076
1077		musb_writeb(epio, MUSB_NAKLIMIT0, 0);
1078
1079		/* clear it */
1080		musb_writew(epio, MUSB_CSR0, 0);
1081	}
1082
1083	if (unlikely(!urb)) {
1084		/* stop endpoint since we have no place for its data, this
1085		 * SHOULD NEVER HAPPEN! */
1086		ERR("no URB for end 0\n");
1087
1088		musb_writew(epio, MUSB_CSR0, MUSB_CSR0_FLUSHFIFO);
1089		musb_writew(epio, MUSB_CSR0, MUSB_CSR0_FLUSHFIFO);
1090		musb_writew(epio, MUSB_CSR0, 0);
1091
1092		goto done;
1093	}
1094
1095	if (!complete) {
1096		/* call common logic and prepare response */
1097		if (musb_h_ep0_continue(musb, len, urb)) {
1098			/* more packets required */
1099			csr = (MUSB_EP0_IN == musb->ep0_stage)
1100				?  MUSB_CSR0_H_REQPKT : MUSB_CSR0_TXPKTRDY;
1101		} else {
1102			/* data transfer complete; perform status phase */
1103			if (usb_pipeout(urb->pipe)
1104					|| !urb->transfer_buffer_length)
1105				csr = MUSB_CSR0_H_STATUSPKT
1106					| MUSB_CSR0_H_REQPKT;
1107			else
1108				csr = MUSB_CSR0_H_STATUSPKT
1109					| MUSB_CSR0_TXPKTRDY;
1110
1111			/* flag status stage */
1112			musb->ep0_stage = MUSB_EP0_STATUS;
1113
1114			DBG(5, "ep0 STATUS, csr %04x\n", csr);
1115
1116		}
1117		musb_writew(epio, MUSB_CSR0, csr);
1118		retval = IRQ_HANDLED;
1119	} else
1120		musb->ep0_stage = MUSB_EP0_IDLE;
1121
1122	/* call completion handler if done */
1123	if (complete)
1124		musb_advance_schedule(musb, urb, hw_ep, 1);
1125done:
1126	return retval;
1127}
1128
1129
1130#ifdef CONFIG_USB_INVENTRA_DMA
1131
1132/* Host side TX (OUT) using Mentor DMA works as follows:
1133	submit_urb ->
1134		- if queue was empty, Program Endpoint
1135		- ... which starts DMA to fifo in mode 1 or 0
1136
1137	DMA Isr (transfer complete) -> TxAvail()
1138		- Stop DMA (~DmaEnab)	(<--- Alert ... currently happens
1139					only in musb_cleanup_urb)
1140		- TxPktRdy has to be set in mode 0 or for
1141			short packets in mode 1.
1142*/
1143
1144#endif
1145
1146/* Service a Tx-Available or dma completion irq for the endpoint */
1147void musb_host_tx(struct musb *musb, u8 epnum)
1148{
1149	int			pipe;
1150	bool			done = false;
1151	u16			tx_csr;
1152	size_t			wLength = 0;
1153	u8			*buf = NULL;
1154	struct urb		*urb;
1155	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1156	void __iomem		*epio = hw_ep->regs;
1157	struct musb_qh		*qh = hw_ep->is_shared_fifo ? hw_ep->in_qh
1158							    : hw_ep->out_qh;
1159	u32			status = 0;
1160	void __iomem		*mbase = musb->mregs;
1161	struct dma_channel	*dma;
1162
1163	urb = next_urb(qh);
1164
1165	musb_ep_select(mbase, epnum);
1166	tx_csr = musb_readw(epio, MUSB_TXCSR);
1167
1168	/* with CPPI, DMA sometimes triggers "extra" irqs */
1169	if (!urb) {
1170		DBG(4, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1171		goto finish;
1172	}
1173
1174	pipe = urb->pipe;
1175	dma = is_dma_capable() ? hw_ep->tx_channel : NULL;
1176	DBG(4, "OUT/TX%d end, csr %04x%s\n", epnum, tx_csr,
1177			dma ? ", dma" : "");
1178
1179	/* check for errors */
1180	if (tx_csr & MUSB_TXCSR_H_RXSTALL) {
1181		/* dma was disabled, fifo flushed */
1182		DBG(3, "TX end %d stall\n", epnum);
1183
1184		/* stall; record URB status */
1185		status = -EPIPE;
1186
1187	} else if (tx_csr & MUSB_TXCSR_H_ERROR) {
1188		/* (NON-ISO) dma was disabled, fifo flushed */
1189		DBG(3, "TX 3strikes on ep=%d\n", epnum);
1190
1191		status = -ETIMEDOUT;
1192
1193	} else if (tx_csr & MUSB_TXCSR_H_NAKTIMEOUT) {
1194		DBG(6, "TX end=%d device not responding\n", epnum);
1195
1196		/* NOTE:  this code path would be a good place to PAUSE a
1197		 * transfer, if there's some other (nonperiodic) tx urb
1198		 * that could use this fifo.  (dma complicates it...)
1199		 *
1200		 * if (bulk && qh->ring.next != &musb->out_bulk), then
1201		 * we have a candidate... NAKing is *NOT* an error
1202		 */
1203		musb_ep_select(mbase, epnum);
1204		musb_writew(epio, MUSB_TXCSR,
1205				MUSB_TXCSR_H_WZC_BITS
1206				| MUSB_TXCSR_TXPKTRDY);
1207		goto finish;
1208	}
1209
1210	if (status) {
1211		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1212			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1213			(void) musb->dma_controller->channel_abort(dma);
1214		}
1215
1216		/* do the proper sequence to abort the transfer in the
1217		 * usb core; the dma engine should already be stopped.
1218		 */
1219		musb_h_tx_flush_fifo(hw_ep);
1220		tx_csr &= ~(MUSB_TXCSR_AUTOSET
1221				| MUSB_TXCSR_DMAENAB
1222				| MUSB_TXCSR_H_ERROR
1223				| MUSB_TXCSR_H_RXSTALL
1224				| MUSB_TXCSR_H_NAKTIMEOUT
1225				);
1226
1227		musb_ep_select(mbase, epnum);
1228		musb_writew(epio, MUSB_TXCSR, tx_csr);
1229		/* REVISIT may need to clear FLUSHFIFO ... */
1230		musb_writew(epio, MUSB_TXCSR, tx_csr);
1231		musb_writeb(epio, MUSB_TXINTERVAL, 0);
1232
1233		done = true;
1234	}
1235
1236	/* second cppi case */
1237	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1238		DBG(4, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1239		goto finish;
1240
1241	}
1242
1243	/* REVISIT this looks wrong... */
1244	if (!status || dma || usb_pipeisoc(pipe)) {
1245		if (dma)
1246			wLength = dma->actual_len;
1247		else
1248			wLength = qh->segsize;
1249		qh->offset += wLength;
1250
1251		if (usb_pipeisoc(pipe)) {
1252			struct usb_iso_packet_descriptor	*d;
1253
1254			d = urb->iso_frame_desc + qh->iso_idx;
1255			d->actual_length = qh->segsize;
1256			if (++qh->iso_idx >= urb->number_of_packets) {
1257				done = true;
1258			} else {
1259				d++;
1260				buf = urb->transfer_buffer + d->offset;
1261				wLength = d->length;
1262			}
1263		} else if (dma) {
1264			done = true;
1265		} else {
1266			/* see if we need to send more data, or ZLP */
1267			if (qh->segsize < qh->maxpacket)
1268				done = true;
1269			else if (qh->offset == urb->transfer_buffer_length
1270					&& !(urb->transfer_flags
1271						& URB_ZERO_PACKET))
1272				done = true;
1273			if (!done) {
1274				buf = urb->transfer_buffer
1275						+ qh->offset;
1276				wLength = urb->transfer_buffer_length
1277						- qh->offset;
1278			}
1279		}
1280	}
1281
1282	/* urb->status != -EINPROGRESS means request has been faulted,
1283	 * so we must abort this transfer after cleanup
1284	 */
1285	if (urb->status != -EINPROGRESS) {
1286		done = true;
1287		if (status == 0)
1288			status = urb->status;
1289	}
1290
1291	if (done) {
1292		/* set status */
1293		urb->status = status;
1294		urb->actual_length = qh->offset;
1295		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_OUT);
1296
1297	} else if (!(tx_csr & MUSB_TXCSR_DMAENAB)) {
1298		/* WARN_ON(!buf); */
1299
1300		/* REVISIT:  some docs say that when hw_ep->tx_double_buffered,
1301		 * (and presumably, fifo is not half-full) we should write TWO
1302		 * packets before updating TXCSR ... other docs disagree ...
1303		 */
1304		/* PIO:  start next packet in this URB */
1305		if (wLength > qh->maxpacket)
1306			wLength = qh->maxpacket;
1307		musb_write_fifo(hw_ep, wLength, buf);
1308		qh->segsize = wLength;
1309
1310		musb_ep_select(mbase, epnum);
1311		musb_writew(epio, MUSB_TXCSR,
1312				MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
1313	} else
1314		DBG(1, "not complete, but dma enabled?\n");
1315
1316finish:
1317	return;
1318}
1319
1320
1321#ifdef CONFIG_USB_INVENTRA_DMA
1322
1323/* Host side RX (IN) using Mentor DMA works as follows:
1324	submit_urb ->
1325		- if queue was empty, ProgramEndpoint
1326		- first IN token is sent out (by setting ReqPkt)
1327	LinuxIsr -> RxReady()
1328	/\	=> first packet is received
1329	|	- Set in mode 0 (DmaEnab, ~ReqPkt)
1330	|		-> DMA Isr (transfer complete) -> RxReady()
1331	|		    - Ack receive (~RxPktRdy), turn off DMA (~DmaEnab)
1332	|		    - if urb not complete, send next IN token (ReqPkt)
1333	|			   |		else complete urb.
1334	|			   |
1335	---------------------------
1336 *
1337 * Nuances of mode 1:
1338 *	For short packets, no ack (+RxPktRdy) is sent automatically
1339 *	(even if AutoClear is ON)
1340 *	For full packets, ack (~RxPktRdy) and next IN token (+ReqPkt) is sent
1341 *	automatically => major problem, as collecting the next packet becomes
1342 *	difficult. Hence mode 1 is not used.
1343 *
1344 * REVISIT
1345 *	All we care about at this driver level is that
1346 *       (a) all URBs terminate with REQPKT cleared and fifo(s) empty;
1347 *       (b) termination conditions are: short RX, or buffer full;
1348 *       (c) fault modes include
1349 *           - iff URB_SHORT_NOT_OK, short RX status is -EREMOTEIO.
1350 *             (and that endpoint's dma queue stops immediately)
1351 *           - overflow (full, PLUS more bytes in the terminal packet)
1352 *
1353 *	So for example, usb-storage sets URB_SHORT_NOT_OK, and would
1354 *	thus be a great candidate for using mode 1 ... for all but the
1355 *	last packet of one URB's transfer.
1356 */
1357
1358#endif
1359
1360/*
1361 * Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
1362 * and high-bandwidth IN transfer cases.
1363 */
1364void musb_host_rx(struct musb *musb, u8 epnum)
1365{
1366	struct urb		*urb;
1367	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1368	void __iomem		*epio = hw_ep->regs;
1369	struct musb_qh		*qh = hw_ep->in_qh;
1370	size_t			xfer_len;
1371	void __iomem		*mbase = musb->mregs;
1372	int			pipe;
1373	u16			rx_csr, val;
1374	bool			iso_err = false;
1375	bool			done = false;
1376	u32			status;
1377	struct dma_channel	*dma;
1378
1379	musb_ep_select(mbase, epnum);
1380
1381	urb = next_urb(qh);
1382	dma = is_dma_capable() ? hw_ep->rx_channel : NULL;
1383	status = 0;
1384	xfer_len = 0;
1385
1386	rx_csr = musb_readw(epio, MUSB_RXCSR);
1387	val = rx_csr;
1388
1389	if (unlikely(!urb)) {
1390		/* REVISIT -- THIS SHOULD NEVER HAPPEN ... but, at least
1391		 * usbtest #11 (unlinks) triggers it regularly, sometimes
1392		 * with fifo full.  (Only with DMA??)
1393		 */
1394		DBG(3, "BOGUS RX%d ready, csr %04x, count %d\n", epnum, val,
1395			musb_readw(epio, MUSB_RXCOUNT));
1396		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1397		return;
1398	}
1399
1400	pipe = urb->pipe;
1401
1402	DBG(5, "<== hw %d rxcsr %04x, urb actual %d (+dma %zu)\n",
1403		epnum, rx_csr, urb->actual_length,
1404		dma ? dma->actual_len : 0);
1405
1406	/* check for errors, concurrent stall & unlink is not really
1407	 * handled yet! */
1408	if (rx_csr & MUSB_RXCSR_H_RXSTALL) {
1409		DBG(3, "RX end %d STALL\n", epnum);
1410
1411		/* stall; record URB status */
1412		status = -EPIPE;
1413
1414	} else if (rx_csr & MUSB_RXCSR_H_ERROR) {
1415		DBG(3, "end %d RX proto error\n", epnum);
1416
1417		status = -EPROTO;
1418		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1419
1420	} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
1421
1422		if (USB_ENDPOINT_XFER_ISOC != qh->type) {
1423			/* NOTE this code path would be a good place to PAUSE a
1424			 * transfer, if there's some other (nonperiodic) rx urb
1425			 * that could use this fifo.  (dma complicates it...)
1426			 *
1427			 * if (bulk && qh->ring.next != &musb->in_bulk), then
1428			 * we have a candidate... NAKing is *NOT* an error
1429			 */
1430			DBG(6, "RX end %d NAK timeout\n", epnum);
1431			musb_ep_select(mbase, epnum);
1432			musb_writew(epio, MUSB_RXCSR,
1433					MUSB_RXCSR_H_WZC_BITS
1434					| MUSB_RXCSR_H_REQPKT);
1435
1436			goto finish;
1437		} else {
1438			DBG(4, "RX end %d ISO data error\n", epnum);
1439			/* packet error reported later */
1440			iso_err = true;
1441		}
1442	}
1443
1444	/* faults abort the transfer */
1445	if (status) {
1446		/* clean up dma and collect transfer count */
1447		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1448			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1449			(void) musb->dma_controller->channel_abort(dma);
1450			xfer_len = dma->actual_len;
1451		}
1452		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1453		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1454		done = true;
1455		goto finish;
1456	}
1457
1458	if (unlikely(dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY)) {
1459		/* SHOULD NEVER HAPPEN ... but at least DaVinci has done it */
1460		ERR("RX%d dma busy, csr %04x\n", epnum, rx_csr);
1461		goto finish;
1462	}
1463
1464	/* thorough shutdown for now ... given more precise fault handling
1465	 * and better queueing support, we might keep a DMA pipeline going
1466	 * while processing this irq for earlier completions.
1467	 */
1468
1469	/* FIXME this is _way_ too much in-line logic for Mentor DMA */
1470
1471#ifndef CONFIG_USB_INVENTRA_DMA
1472	if (rx_csr & MUSB_RXCSR_H_REQPKT)  {
1473		/* REVISIT this happened for a while on some short reads...
1474		 * the cleanup still needs investigation... looks bad...
1475		 * and also duplicates dma cleanup code above ... plus,
1476		 * shouldn't this be the "half full" double buffer case?
1477		 */
1478		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1479			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1480			(void) musb->dma_controller->channel_abort(dma);
1481			xfer_len = dma->actual_len;
1482			done = true;
1483		}
1484
1485		DBG(2, "RXCSR%d %04x, reqpkt, len %zu%s\n", epnum, rx_csr,
1486				xfer_len, dma ? ", dma" : "");
1487		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
1488
1489		musb_ep_select(mbase, epnum);
1490		musb_writew(epio, MUSB_RXCSR,
1491				MUSB_RXCSR_H_WZC_BITS | rx_csr);
1492	}
1493#endif
1494	if (dma && (rx_csr & MUSB_RXCSR_DMAENAB)) {
1495		xfer_len = dma->actual_len;
1496
1497		val &= ~(MUSB_RXCSR_DMAENAB
1498			| MUSB_RXCSR_H_AUTOREQ
1499			| MUSB_RXCSR_AUTOCLEAR
1500			| MUSB_RXCSR_RXPKTRDY);
1501		musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1502
1503#ifdef CONFIG_USB_INVENTRA_DMA
1504		if (usb_pipeisoc(pipe)) {
1505			struct usb_iso_packet_descriptor *d;
1506
1507			d = urb->iso_frame_desc + qh->iso_idx;
1508			d->actual_length = xfer_len;
1509
1510			/* even if there was an error, we did the dma
1511			 * for iso_frame_desc->length
1512			 */
1513			if (d->status != EILSEQ && d->status != -EOVERFLOW)
1514				d->status = 0;
1515
1516			if (++qh->iso_idx >= urb->number_of_packets)
1517				done = true;
1518			else
1519				done = false;
1520
1521		} else  {
1522		/* done if urb buffer is full or short packet is recd */
1523		done = (urb->actual_length + xfer_len >=
1524				urb->transfer_buffer_length
1525			|| dma->actual_len < qh->maxpacket);
1526		}
1527
1528		/* send IN token for next packet, without AUTOREQ */
1529		if (!done) {
1530			val |= MUSB_RXCSR_H_REQPKT;
1531			musb_writew(epio, MUSB_RXCSR,
1532				MUSB_RXCSR_H_WZC_BITS | val);
1533		}
1534
1535		DBG(4, "ep %d dma %s, rxcsr %04x, rxcount %d\n", epnum,
1536			done ? "off" : "reset",
1537			musb_readw(epio, MUSB_RXCSR),
1538			musb_readw(epio, MUSB_RXCOUNT));
1539#else
1540		done = true;
1541#endif
1542	} else if (urb->status == -EINPROGRESS) {
1543		/* if no errors, be sure a packet is ready for unloading */
1544		if (unlikely(!(rx_csr & MUSB_RXCSR_RXPKTRDY))) {
1545			status = -EPROTO;
1546			ERR("Rx interrupt with no errors or packet!\n");
1547
1548			/* FIXME this is another "SHOULD NEVER HAPPEN" */
1549
1550/* SCRUB (RX) */
1551			/* do the proper sequence to abort the transfer */
1552			musb_ep_select(mbase, epnum);
1553			val &= ~MUSB_RXCSR_H_REQPKT;
1554			musb_writew(epio, MUSB_RXCSR, val);
1555			goto finish;
1556		}
1557
1558		/* we are expecting IN packets */
1559#ifdef CONFIG_USB_INVENTRA_DMA
1560		if (dma) {
1561			struct dma_controller	*c;
1562			u16			rx_count;
1563			int			ret, length;
1564			dma_addr_t		buf;
1565
1566			rx_count = musb_readw(epio, MUSB_RXCOUNT);
1567
1568			DBG(2, "RX%d count %d, buffer 0x%x len %d/%d\n",
1569					epnum, rx_count,
1570					urb->transfer_dma
1571						+ urb->actual_length,
1572					qh->offset,
1573					urb->transfer_buffer_length);
1574
1575			c = musb->dma_controller;
1576
1577			if (usb_pipeisoc(pipe)) {
1578				int status = 0;
1579				struct usb_iso_packet_descriptor *d;
1580
1581				d = urb->iso_frame_desc + qh->iso_idx;
1582
1583				if (iso_err) {
1584					status = -EILSEQ;
1585					urb->error_count++;
1586				}
1587				if (rx_count > d->length) {
1588					if (status == 0) {
1589						status = -EOVERFLOW;
1590						urb->error_count++;
1591					}
1592					DBG(2, "** OVERFLOW %d into %d\n",\
1593					    rx_count, d->length);
1594
1595					length = d->length;
1596				} else
1597					length = rx_count;
1598				d->status = status;
1599				buf = urb->transfer_dma + d->offset;
1600			} else {
1601				length = rx_count;
1602				buf = urb->transfer_dma +
1603						urb->actual_length;
1604			}
1605
1606			dma->desired_mode = 0;
1607#ifdef USE_MODE1
1608			/* because of the issue below, mode 1 will
1609			 * only rarely behave with correct semantics.
1610			 */
1611			if ((urb->transfer_flags &
1612						URB_SHORT_NOT_OK)
1613				&& (urb->transfer_buffer_length -
1614						urb->actual_length)
1615					> qh->maxpacket)
1616				dma->desired_mode = 1;
1617			if (rx_count < hw_ep->max_packet_sz_rx) {
1618				length = rx_count;
1619				dma->bDesiredMode = 0;
1620			} else {
1621				length = urb->transfer_buffer_length;
1622			}
1623#endif
1624
1625/* Disadvantage of using mode 1:
1626 *	It's basically usable only for mass storage class; essentially all
1627 *	other protocols also terminate transfers on short packets.
1628 *
1629 * Details:
1630 *	An extra IN token is sent at the end of the transfer (due to AUTOREQ)
1631 *	If you try to use mode 1 for (transfer_buffer_length - 512), and try
1632 *	to use the extra IN token to grab the last packet using mode 0, then
1633 *	the problem is that you cannot be sure when the device will send the
1634 *	last packet and RxPktRdy set. Sometimes the packet is recd too soon
1635 *	such that it gets lost when RxCSR is re-set at the end of the mode 1
1636 *	transfer, while sometimes it is recd just a little late so that if you
1637 *	try to configure for mode 0 soon after the mode 1 transfer is
1638 *	completed, you will find rxcount 0. Okay, so you might think why not
1639 *	wait for an interrupt when the pkt is recd. Well, you won't get any!
1640 */
1641
1642			val = musb_readw(epio, MUSB_RXCSR);
1643			val &= ~MUSB_RXCSR_H_REQPKT;
1644
1645			if (dma->desired_mode == 0)
1646				val &= ~MUSB_RXCSR_H_AUTOREQ;
1647			else
1648				val |= MUSB_RXCSR_H_AUTOREQ;
1649			val |= MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAENAB;
1650
1651			musb_writew(epio, MUSB_RXCSR,
1652				MUSB_RXCSR_H_WZC_BITS | val);
1653
1654			/* REVISIT if when actual_length != 0,
1655			 * transfer_buffer_length needs to be
1656			 * adjusted first...
1657			 */
1658			ret = c->channel_program(
1659				dma, qh->maxpacket,
1660				dma->desired_mode, buf, length);
1661
1662			if (!ret) {
1663				c->channel_release(dma);
1664				hw_ep->rx_channel = NULL;
1665				dma = NULL;
1666				/* REVISIT reset CSR */
1667			}
1668		}
1669#endif	/* Mentor DMA */
1670
1671		if (!dma) {
1672			done = musb_host_packet_rx(musb, urb,
1673					epnum, iso_err);
1674			DBG(6, "read %spacket\n", done ? "last " : "");
1675		}
1676	}
1677
1678finish:
1679	urb->actual_length += xfer_len;
1680	qh->offset += xfer_len;
1681	if (done) {
1682		if (urb->status == -EINPROGRESS)
1683			urb->status = status;
1684		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_IN);
1685	}
1686}
1687
1688/* schedule nodes correspond to peripheral endpoints, like an OHCI QH.
1689 * the software schedule associates multiple such nodes with a given
1690 * host side hardware endpoint + direction; scheduling may activate
1691 * that hardware endpoint.
1692 */
1693static int musb_schedule(
1694	struct musb		*musb,
1695	struct musb_qh		*qh,
1696	int			is_in)
1697{
1698	int			idle;
1699	int			best_diff;
1700	int			best_end, epnum;
1701	struct musb_hw_ep	*hw_ep = NULL;
1702	struct list_head	*head = NULL;
1703
1704	/* use fixed hardware for control and bulk */
1705	if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
1706		head = &musb->control;
1707		hw_ep = musb->control_ep;
1708		goto success;
1709	}
1710
1711	/* else, periodic transfers get muxed to other endpoints */
1712
1713	/*
1714	 * We know this qh hasn't been scheduled, so all we need to do
1715	 * is choose which hardware endpoint to put it on ...
1716	 *
1717	 * REVISIT what we really want here is a regular schedule tree
1718	 * like e.g. OHCI uses.
1719	 */
1720	best_diff = 4096;
1721	best_end = -1;
1722
1723	for (epnum = 1, hw_ep = musb->endpoints + 1;
1724			epnum < musb->nr_endpoints;
1725			epnum++, hw_ep++) {
1726		int	diff;
1727
1728		if (is_in || hw_ep->is_shared_fifo) {
1729			if (hw_ep->in_qh  != NULL)
1730				continue;
1731		} else	if (hw_ep->out_qh != NULL)
1732			continue;
1733
1734		if (hw_ep == musb->bulk_ep)
1735			continue;
1736
1737		if (is_in)
1738			diff = hw_ep->max_packet_sz_rx - qh->maxpacket;
1739		else
1740			diff = hw_ep->max_packet_sz_tx - qh->maxpacket;
1741
1742		if (diff >= 0 && best_diff > diff) {
1743			best_diff = diff;
1744			best_end = epnum;
1745		}
1746	}
1747	/* use bulk reserved ep1 if no other ep is free */
1748	if (best_end < 0 && qh->type == USB_ENDPOINT_XFER_BULK) {
1749		hw_ep = musb->bulk_ep;
1750		if (is_in)
1751			head = &musb->in_bulk;
1752		else
1753			head = &musb->out_bulk;
1754		goto success;
1755	} else if (best_end < 0) {
1756		return -ENOSPC;
1757	}
1758
1759	idle = 1;
1760	qh->mux = 0;
1761	hw_ep = musb->endpoints + best_end;
1762	DBG(4, "qh %p periodic slot %d\n", qh, best_end);
1763success:
1764	if (head) {
1765		idle = list_empty(head);
1766		list_add_tail(&qh->ring, head);
1767		qh->mux = 1;
1768	}
1769	qh->hw_ep = hw_ep;
1770	qh->hep->hcpriv = qh;
1771	if (idle)
1772		musb_start_urb(musb, is_in, qh);
1773	return 0;
1774}
1775
1776static int musb_urb_enqueue(
1777	struct usb_hcd			*hcd,
1778	struct urb			*urb,
1779	gfp_t				mem_flags)
1780{
1781	unsigned long			flags;
1782	struct musb			*musb = hcd_to_musb(hcd);
1783	struct usb_host_endpoint	*hep = urb->ep;
1784	struct musb_qh			*qh = hep->hcpriv;
1785	struct usb_endpoint_descriptor	*epd = &hep->desc;
1786	int				ret;
1787	unsigned			type_reg;
1788	unsigned			interval;
1789
1790	/* host role must be active */
1791	if (!is_host_active(musb) || !musb->is_active)
1792		return -ENODEV;
1793
1794	spin_lock_irqsave(&musb->lock, flags);
1795	ret = usb_hcd_link_urb_to_ep(hcd, urb);
1796	spin_unlock_irqrestore(&musb->lock, flags);
1797	if (ret)
1798		return ret;
1799
1800	/* DMA mapping was already done, if needed, and this urb is on
1801	 * hep->urb_list ... so there's little to do unless hep wasn't
1802	 * yet scheduled onto a live qh.
1803	 *
1804	 * REVISIT best to keep hep->hcpriv valid until the endpoint gets
1805	 * disabled, testing for empty qh->ring and avoiding qh setup costs
1806	 * except for the first urb queued after a config change.
1807	 */
1808	if (qh) {
1809		urb->hcpriv = qh;
1810		return 0;
1811	}
1812
1813	/* Allocate and initialize qh, minimizing the work done each time
1814	 * hw_ep gets reprogrammed, or with irqs blocked.  Then schedule it.
1815	 *
1816	 * REVISIT consider a dedicated qh kmem_cache, so it's harder
1817	 * for bugs in other kernel code to break this driver...
1818	 */
1819	qh = kzalloc(sizeof *qh, mem_flags);
1820	if (!qh) {
1821		spin_lock_irqsave(&musb->lock, flags);
1822		usb_hcd_unlink_urb_from_ep(hcd, urb);
1823		spin_unlock_irqrestore(&musb->lock, flags);
1824		return -ENOMEM;
1825	}
1826
1827	qh->hep = hep;
1828	qh->dev = urb->dev;
1829	INIT_LIST_HEAD(&qh->ring);
1830	qh->is_ready = 1;
1831
1832	qh->maxpacket = le16_to_cpu(epd->wMaxPacketSize);
1833
1834	/* no high bandwidth support yet */
1835	if (qh->maxpacket & ~0x7ff) {
1836		ret = -EMSGSIZE;
1837		goto done;
1838	}
1839
1840	qh->epnum = usb_endpoint_num(epd);
1841	qh->type = usb_endpoint_type(epd);
1842
1843	/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
1844	qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
1845
1846	/* precompute rxtype/txtype/type0 register */
1847	type_reg = (qh->type << 4) | qh->epnum;
1848	switch (urb->dev->speed) {
1849	case USB_SPEED_LOW:
1850		type_reg |= 0xc0;
1851		break;
1852	case USB_SPEED_FULL:
1853		type_reg |= 0x80;
1854		break;
1855	default:
1856		type_reg |= 0x40;
1857	}
1858	qh->type_reg = type_reg;
1859
1860	/* Precompute RXINTERVAL/TXINTERVAL register */
1861	switch (qh->type) {
1862	case USB_ENDPOINT_XFER_INT:
1863		/*
1864		 * Full/low speeds use the  linear encoding,
1865		 * high speed uses the logarithmic encoding.
1866		 */
1867		if (urb->dev->speed <= USB_SPEED_FULL) {
1868			interval = max_t(u8, epd->bInterval, 1);
1869			break;
1870		}
1871		/* FALLTHROUGH */
1872	case USB_ENDPOINT_XFER_ISOC:
1873		/* ISO always uses logarithmic encoding */
1874		interval = min_t(u8, epd->bInterval, 16);
1875		break;
1876	default:
1877		/* REVISIT we actually want to use NAK limits, hinting to the
1878		 * transfer scheduling logic to try some other qh, e.g. try
1879		 * for 2 msec first:
1880		 *
1881		 * interval = (USB_SPEED_HIGH == urb->dev->speed) ? 16 : 2;
1882		 *
1883		 * The downside of disabling this is that transfer scheduling
1884		 * gets VERY unfair for nonperiodic transfers; a misbehaving
1885		 * peripheral could make that hurt.  Or for reads, one that's
1886		 * perfectly normal:  network and other drivers keep reads
1887		 * posted at all times, having one pending for a week should
1888		 * be perfectly safe.
1889		 *
1890		 * The upside of disabling it is avoidng transfer scheduling
1891		 * code to put this aside for while.
1892		 */
1893		interval = 0;
1894	}
1895	qh->intv_reg = interval;
1896
1897	/* precompute addressing for external hub/tt ports */
1898	if (musb->is_multipoint) {
1899		struct usb_device	*parent = urb->dev->parent;
1900
1901		if (parent != hcd->self.root_hub) {
1902			qh->h_addr_reg = (u8) parent->devnum;
1903
1904			/* set up tt info if needed */
1905			if (urb->dev->tt) {
1906				qh->h_port_reg = (u8) urb->dev->ttport;
1907				if (urb->dev->tt->hub)
1908					qh->h_addr_reg =
1909						(u8) urb->dev->tt->hub->devnum;
1910				if (urb->dev->tt->multi)
1911					qh->h_addr_reg |= 0x80;
1912			}
1913		}
1914	}
1915
1916	/* invariant: hep->hcpriv is null OR the qh that's already scheduled.
1917	 * until we get real dma queues (with an entry for each urb/buffer),
1918	 * we only have work to do in the former case.
1919	 */
1920	spin_lock_irqsave(&musb->lock, flags);
1921	if (hep->hcpriv) {
1922		/* some concurrent activity submitted another urb to hep...
1923		 * odd, rare, error prone, but legal.
1924		 */
1925		kfree(qh);
1926		ret = 0;
1927	} else
1928		ret = musb_schedule(musb, qh,
1929				epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK);
1930
1931	if (ret == 0) {
1932		urb->hcpriv = qh;
1933		/* FIXME set urb->start_frame for iso/intr, it's tested in
1934		 * musb_start_urb(), but otherwise only konicawc cares ...
1935		 */
1936	}
1937	spin_unlock_irqrestore(&musb->lock, flags);
1938
1939done:
1940	if (ret != 0) {
1941		spin_lock_irqsave(&musb->lock, flags);
1942		usb_hcd_unlink_urb_from_ep(hcd, urb);
1943		spin_unlock_irqrestore(&musb->lock, flags);
1944		kfree(qh);
1945	}
1946	return ret;
1947}
1948
1949
1950/*
1951 * abort a transfer that's at the head of a hardware queue.
1952 * called with controller locked, irqs blocked
1953 * that hardware queue advances to the next transfer, unless prevented
1954 */
1955static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh, int is_in)
1956{
1957	struct musb_hw_ep	*ep = qh->hw_ep;
1958	void __iomem		*epio = ep->regs;
1959	unsigned		hw_end = ep->epnum;
1960	void __iomem		*regs = ep->musb->mregs;
1961	u16			csr;
1962	int			status = 0;
1963
1964	musb_ep_select(regs, hw_end);
1965
1966	if (is_dma_capable()) {
1967		struct dma_channel	*dma;
1968
1969		dma = is_in ? ep->rx_channel : ep->tx_channel;
1970		if (dma) {
1971			status = ep->musb->dma_controller->channel_abort(dma);
1972			DBG(status ? 1 : 3,
1973				"abort %cX%d DMA for urb %p --> %d\n",
1974				is_in ? 'R' : 'T', ep->epnum,
1975				urb, status);
1976			urb->actual_length += dma->actual_len;
1977		}
1978	}
1979
1980	/* turn off DMA requests, discard state, stop polling ... */
1981	if (is_in) {
1982		/* giveback saves bulk toggle */
1983		csr = musb_h_flush_rxfifo(ep, 0);
1984
1985		/* REVISIT we still get an irq; should likely clear the
1986		 * endpoint's irq status here to avoid bogus irqs.
1987		 * clearing that status is platform-specific...
1988		 */
1989	} else {
1990		musb_h_tx_flush_fifo(ep);
1991		csr = musb_readw(epio, MUSB_TXCSR);
1992		csr &= ~(MUSB_TXCSR_AUTOSET
1993			| MUSB_TXCSR_DMAENAB
1994			| MUSB_TXCSR_H_RXSTALL
1995			| MUSB_TXCSR_H_NAKTIMEOUT
1996			| MUSB_TXCSR_H_ERROR
1997			| MUSB_TXCSR_TXPKTRDY);
1998		musb_writew(epio, MUSB_TXCSR, csr);
1999		/* REVISIT may need to clear FLUSHFIFO ... */
2000		musb_writew(epio, MUSB_TXCSR, csr);
2001		/* flush cpu writebuffer */
2002		csr = musb_readw(epio, MUSB_TXCSR);
2003	}
2004	if (status == 0)
2005		musb_advance_schedule(ep->musb, urb, ep, is_in);
2006	return status;
2007}
2008
2009static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
2010{
2011	struct musb		*musb = hcd_to_musb(hcd);
2012	struct musb_qh		*qh;
2013	struct list_head	*sched;
2014	unsigned long		flags;
2015	int			ret;
2016
2017	DBG(4, "urb=%p, dev%d ep%d%s\n", urb,
2018			usb_pipedevice(urb->pipe),
2019			usb_pipeendpoint(urb->pipe),
2020			usb_pipein(urb->pipe) ? "in" : "out");
2021
2022	spin_lock_irqsave(&musb->lock, flags);
2023	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
2024	if (ret)
2025		goto done;
2026
2027	qh = urb->hcpriv;
2028	if (!qh)
2029		goto done;
2030
2031	/* Any URB not actively programmed into endpoint hardware can be
2032	 * immediately given back; that's any URB not at the head of an
2033	 * endpoint queue, unless someday we get real DMA queues.  And even
2034	 * if it's at the head, it might not be known to the hardware...
2035	 *
2036	 * Otherwise abort current transfer, pending dma, etc.; urb->status
2037	 * has already been updated.  This is a synchronous abort; it'd be
2038	 * OK to hold off until after some IRQ, though.
2039	 */
2040	if (!qh->is_ready || urb->urb_list.prev != &qh->hep->urb_list)
2041		ret = -EINPROGRESS;
2042	else {
2043		switch (qh->type) {
2044		case USB_ENDPOINT_XFER_CONTROL:
2045			sched = &musb->control;
2046			break;
2047		case USB_ENDPOINT_XFER_BULK:
2048			if (qh->mux == 1) {
2049				if (usb_pipein(urb->pipe))
2050					sched = &musb->in_bulk;
2051				else
2052					sched = &musb->out_bulk;
2053				break;
2054			}
2055		default:
2056			/* REVISIT when we get a schedule tree, periodic
2057			 * transfers won't always be at the head of a
2058			 * singleton queue...
2059			 */
2060			sched = NULL;
2061			break;
2062		}
2063	}
2064
2065	/* NOTE:  qh is invalid unless !list_empty(&hep->urb_list) */
2066	if (ret < 0 || (sched && qh != first_qh(sched))) {
2067		int	ready = qh->is_ready;
2068
2069		ret = 0;
2070		qh->is_ready = 0;
2071		__musb_giveback(musb, urb, 0);
2072		qh->is_ready = ready;
2073
2074		/* If nothing else (usually musb_giveback) is using it
2075		 * and its URB list has emptied, recycle this qh.
2076		 */
2077		if (ready && list_empty(&qh->hep->urb_list)) {
2078			qh->hep->hcpriv = NULL;
2079			list_del(&qh->ring);
2080			kfree(qh);
2081		}
2082	} else
2083		ret = musb_cleanup_urb(urb, qh, urb->pipe & USB_DIR_IN);
2084done:
2085	spin_unlock_irqrestore(&musb->lock, flags);
2086	return ret;
2087}
2088
2089/* disable an endpoint */
2090static void
2091musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
2092{
2093	u8			epnum = hep->desc.bEndpointAddress;
2094	unsigned long		flags;
2095	struct musb		*musb = hcd_to_musb(hcd);
2096	u8			is_in = epnum & USB_DIR_IN;
2097	struct musb_qh		*qh;
2098	struct urb		*urb;
2099	struct list_head	*sched;
2100
2101	spin_lock_irqsave(&musb->lock, flags);
2102
2103	qh = hep->hcpriv;
2104	if (qh == NULL)
2105		goto exit;
2106
2107	switch (qh->type) {
2108	case USB_ENDPOINT_XFER_CONTROL:
2109		sched = &musb->control;
2110		break;
2111	case USB_ENDPOINT_XFER_BULK:
2112		if (qh->mux == 1) {
2113			if (is_in)
2114				sched = &musb->in_bulk;
2115			else
2116				sched = &musb->out_bulk;
2117			break;
2118		}
2119	default:
2120		/* REVISIT when we get a schedule tree, periodic transfers
2121		 * won't always be at the head of a singleton queue...
2122		 */
2123		sched = NULL;
2124		break;
2125	}
2126
2127	/* NOTE:  qh is invalid unless !list_empty(&hep->urb_list) */
2128
2129	/* kick first urb off the hardware, if needed */
2130	qh->is_ready = 0;
2131	if (!sched || qh == first_qh(sched)) {
2132		urb = next_urb(qh);
2133
2134		/* make software (then hardware) stop ASAP */
2135		if (!urb->unlinked)
2136			urb->status = -ESHUTDOWN;
2137
2138		/* cleanup */
2139		musb_cleanup_urb(urb, qh, urb->pipe & USB_DIR_IN);
2140
2141		/* Then nuke all the others ... and advance the
2142		 * queue on hw_ep (e.g. bulk ring) when we're done.
2143		 */
2144		while (!list_empty(&hep->urb_list)) {
2145			urb = next_urb(qh);
2146			urb->status = -ESHUTDOWN;
2147			musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
2148		}
2149	} else {
2150		/* Just empty the queue; the hardware is busy with
2151		 * other transfers, and since !qh->is_ready nothing
2152		 * will activate any of these as it advances.
2153		 */
2154		while (!list_empty(&hep->urb_list))
2155			__musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
2156
2157		hep->hcpriv = NULL;
2158		list_del(&qh->ring);
2159		kfree(qh);
2160	}
2161exit:
2162	spin_unlock_irqrestore(&musb->lock, flags);
2163}
2164
2165static int musb_h_get_frame_number(struct usb_hcd *hcd)
2166{
2167	struct musb	*musb = hcd_to_musb(hcd);
2168
2169	return musb_readw(musb->mregs, MUSB_FRAME);
2170}
2171
2172static int musb_h_start(struct usb_hcd *hcd)
2173{
2174	struct musb	*musb = hcd_to_musb(hcd);
2175
2176	/* NOTE: musb_start() is called when the hub driver turns
2177	 * on port power, or when (OTG) peripheral starts.
2178	 */
2179	hcd->state = HC_STATE_RUNNING;
2180	musb->port1_status = 0;
2181	return 0;
2182}
2183
2184static void musb_h_stop(struct usb_hcd *hcd)
2185{
2186	musb_stop(hcd_to_musb(hcd));
2187	hcd->state = HC_STATE_HALT;
2188}
2189
2190static int musb_bus_suspend(struct usb_hcd *hcd)
2191{
2192	struct musb	*musb = hcd_to_musb(hcd);
2193
2194	if (musb->xceiv.state == OTG_STATE_A_SUSPEND)
2195		return 0;
2196
2197	if (is_host_active(musb) && musb->is_active) {
2198		WARNING("trying to suspend as %s is_active=%i\n",
2199			otg_state_string(musb), musb->is_active);
2200		return -EBUSY;
2201	} else
2202		return 0;
2203}
2204
2205static int musb_bus_resume(struct usb_hcd *hcd)
2206{
2207	/* resuming child port does the work */
2208	return 0;
2209}
2210
2211const struct hc_driver musb_hc_driver = {
2212	.description		= "musb-hcd",
2213	.product_desc		= "MUSB HDRC host driver",
2214	.hcd_priv_size		= sizeof(struct musb),
2215	.flags			= HCD_USB2 | HCD_MEMORY,
2216
2217	/* not using irq handler or reset hooks from usbcore, since
2218	 * those must be shared with peripheral code for OTG configs
2219	 */
2220
2221	.start			= musb_h_start,
2222	.stop			= musb_h_stop,
2223
2224	.get_frame_number	= musb_h_get_frame_number,
2225
2226	.urb_enqueue		= musb_urb_enqueue,
2227	.urb_dequeue		= musb_urb_dequeue,
2228	.endpoint_disable	= musb_h_disable,
2229
2230	.hub_status_data	= musb_hub_status_data,
2231	.hub_control		= musb_hub_control,
2232	.bus_suspend		= musb_bus_suspend,
2233	.bus_resume		= musb_bus_resume,
2234	/* .start_port_reset	= NULL, */
2235	/* .hub_irq_enable	= NULL, */
2236};
2237