xref: /openbmc/linux/drivers/usb/musb/musb_host.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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  * Copyright (C) 2008-2009 MontaVista Software, Inc. <source@mvista.com>
8  *
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.
12  *
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.
17  *
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
21  * 02110-1301 USA
22  *
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.
33  *
34  */
35 
36 #include <linux/module.h>
37 #include <linux/kernel.h>
38 #include <linux/delay.h>
39 #include <linux/sched.h>
40 #include <linux/slab.h>
41 #include <linux/errno.h>
42 #include <linux/init.h>
43 #include <linux/list.h>
44 #include <linux/dma-mapping.h>
45 
46 #include "musb_core.h"
47 #include "musb_host.h"
48 
49 
50 /* MUSB HOST status 22-mar-2006
51  *
52  * - There's still lots of partial code duplication for fault paths, so
53  *   they aren't handled as consistently as they need to be.
54  *
55  * - PIO mostly behaved when last tested.
56  *     + including ep0, with all usbtest cases 9, 10
57  *     + usbtest 14 (ep0out) doesn't seem to run at all
58  *     + double buffered OUT/TX endpoints saw stalls(!) with certain usbtest
59  *       configurations, but otherwise double buffering passes basic tests.
60  *     + for 2.6.N, for N > ~10, needs API changes for hcd framework.
61  *
62  * - DMA (CPPI) ... partially behaves, not currently recommended
63  *     + about 1/15 the speed of typical EHCI implementations (PCI)
64  *     + RX, all too often reqpkt seems to misbehave after tx
65  *     + TX, no known issues (other than evident silicon issue)
66  *
67  * - DMA (Mentor/OMAP) ...has at least toggle update problems
68  *
69  * - [23-feb-2009] minimal traffic scheduling to avoid bulk RX packet
70  *   starvation ... nothing yet for TX, interrupt, or bulk.
71  *
72  * - Not tested with HNP, but some SRP paths seem to behave.
73  *
74  * NOTE 24-August-2006:
75  *
76  * - Bulk traffic finally uses both sides of hardware ep1, freeing up an
77  *   extra endpoint for periodic use enabling hub + keybd + mouse.  That
78  *   mostly works, except that with "usbnet" it's easy to trigger cases
79  *   with "ping" where RX loses.  (a) ping to davinci, even "ping -f",
80  *   fine; but (b) ping _from_ davinci, even "ping -c 1", ICMP RX loses
81  *   although ARP RX wins.  (That test was done with a full speed link.)
82  */
83 
84 
85 /*
86  * NOTE on endpoint usage:
87  *
88  * CONTROL transfers all go through ep0.  BULK ones go through dedicated IN
89  * and OUT endpoints ... hardware is dedicated for those "async" queue(s).
90  * (Yes, bulk _could_ use more of the endpoints than that, and would even
91  * benefit from it.)
92  *
93  * INTERUPPT and ISOCHRONOUS transfers are scheduled to the other endpoints.
94  * So far that scheduling is both dumb and optimistic:  the endpoint will be
95  * "claimed" until its software queue is no longer refilled.  No multiplexing
96  * of transfers between endpoints, or anything clever.
97  */
98 
99 
100 static void musb_ep_program(struct musb *musb, u8 epnum,
101 			struct urb *urb, int is_out,
102 			u8 *buf, u32 offset, u32 len);
103 
104 /*
105  * Clear TX fifo. Needed to avoid BABBLE errors.
106  */
107 static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
108 {
109 	void __iomem	*epio = ep->regs;
110 	u16		csr;
111 	u16		lastcsr = 0;
112 	int		retries = 1000;
113 
114 	csr = musb_readw(epio, MUSB_TXCSR);
115 	while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
116 		if (csr != lastcsr)
117 			DBG(3, "Host TX FIFONOTEMPTY csr: %02x\n", csr);
118 		lastcsr = csr;
119 		csr |= MUSB_TXCSR_FLUSHFIFO;
120 		musb_writew(epio, MUSB_TXCSR, csr);
121 		csr = musb_readw(epio, MUSB_TXCSR);
122 		if (WARN(retries-- < 1,
123 				"Could not flush host TX%d fifo: csr: %04x\n",
124 				ep->epnum, csr))
125 			return;
126 		mdelay(1);
127 	}
128 }
129 
130 static void musb_h_ep0_flush_fifo(struct musb_hw_ep *ep)
131 {
132 	void __iomem	*epio = ep->regs;
133 	u16		csr;
134 	int		retries = 5;
135 
136 	/* scrub any data left in the fifo */
137 	do {
138 		csr = musb_readw(epio, MUSB_TXCSR);
139 		if (!(csr & (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_RXPKTRDY)))
140 			break;
141 		musb_writew(epio, MUSB_TXCSR, MUSB_CSR0_FLUSHFIFO);
142 		csr = musb_readw(epio, MUSB_TXCSR);
143 		udelay(10);
144 	} while (--retries);
145 
146 	WARN(!retries, "Could not flush host TX%d fifo: csr: %04x\n",
147 			ep->epnum, csr);
148 
149 	/* and reset for the next transfer */
150 	musb_writew(epio, MUSB_TXCSR, 0);
151 }
152 
153 /*
154  * Start transmit. Caller is responsible for locking shared resources.
155  * musb must be locked.
156  */
157 static inline void musb_h_tx_start(struct musb_hw_ep *ep)
158 {
159 	u16	txcsr;
160 
161 	/* NOTE: no locks here; caller should lock and select EP */
162 	if (ep->epnum) {
163 		txcsr = musb_readw(ep->regs, MUSB_TXCSR);
164 		txcsr |= MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_H_WZC_BITS;
165 		musb_writew(ep->regs, MUSB_TXCSR, txcsr);
166 	} else {
167 		txcsr = MUSB_CSR0_H_SETUPPKT | MUSB_CSR0_TXPKTRDY;
168 		musb_writew(ep->regs, MUSB_CSR0, txcsr);
169 	}
170 
171 }
172 
173 static inline void musb_h_tx_dma_start(struct musb_hw_ep *ep)
174 {
175 	u16	txcsr;
176 
177 	/* NOTE: no locks here; caller should lock and select EP */
178 	txcsr = musb_readw(ep->regs, MUSB_TXCSR);
179 	txcsr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_H_WZC_BITS;
180 	if (is_cppi_enabled())
181 		txcsr |= MUSB_TXCSR_DMAMODE;
182 	musb_writew(ep->regs, MUSB_TXCSR, txcsr);
183 }
184 
185 static void musb_ep_set_qh(struct musb_hw_ep *ep, int is_in, struct musb_qh *qh)
186 {
187 	if (is_in != 0 || ep->is_shared_fifo)
188 		ep->in_qh  = qh;
189 	if (is_in == 0 || ep->is_shared_fifo)
190 		ep->out_qh = qh;
191 }
192 
193 static struct musb_qh *musb_ep_get_qh(struct musb_hw_ep *ep, int is_in)
194 {
195 	return is_in ? ep->in_qh : ep->out_qh;
196 }
197 
198 /*
199  * Start the URB at the front of an endpoint's queue
200  * end must be claimed from the caller.
201  *
202  * Context: controller locked, irqs blocked
203  */
204 static void
205 musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
206 {
207 	u16			frame;
208 	u32			len;
209 	void __iomem		*mbase =  musb->mregs;
210 	struct urb		*urb = next_urb(qh);
211 	void			*buf = urb->transfer_buffer;
212 	u32			offset = 0;
213 	struct musb_hw_ep	*hw_ep = qh->hw_ep;
214 	unsigned		pipe = urb->pipe;
215 	u8			address = usb_pipedevice(pipe);
216 	int			epnum = hw_ep->epnum;
217 
218 	/* initialize software qh state */
219 	qh->offset = 0;
220 	qh->segsize = 0;
221 
222 	/* gather right source of data */
223 	switch (qh->type) {
224 	case USB_ENDPOINT_XFER_CONTROL:
225 		/* control transfers always start with SETUP */
226 		is_in = 0;
227 		musb->ep0_stage = MUSB_EP0_START;
228 		buf = urb->setup_packet;
229 		len = 8;
230 		break;
231 	case USB_ENDPOINT_XFER_ISOC:
232 		qh->iso_idx = 0;
233 		qh->frame = 0;
234 		offset = urb->iso_frame_desc[0].offset;
235 		len = urb->iso_frame_desc[0].length;
236 		break;
237 	default:		/* bulk, interrupt */
238 		/* actual_length may be nonzero on retry paths */
239 		buf = urb->transfer_buffer + urb->actual_length;
240 		len = urb->transfer_buffer_length - urb->actual_length;
241 	}
242 
243 	DBG(4, "qh %p urb %p dev%d ep%d%s%s, hw_ep %d, %p/%d\n",
244 			qh, urb, address, qh->epnum,
245 			is_in ? "in" : "out",
246 			({char *s; switch (qh->type) {
247 			case USB_ENDPOINT_XFER_CONTROL:	s = ""; break;
248 			case USB_ENDPOINT_XFER_BULK:	s = "-bulk"; break;
249 			case USB_ENDPOINT_XFER_ISOC:	s = "-iso"; break;
250 			default:			s = "-intr"; break;
251 			}; s; }),
252 			epnum, buf + offset, len);
253 
254 	/* Configure endpoint */
255 	musb_ep_set_qh(hw_ep, is_in, qh);
256 	musb_ep_program(musb, epnum, urb, !is_in, buf, offset, len);
257 
258 	/* transmit may have more work: start it when it is time */
259 	if (is_in)
260 		return;
261 
262 	/* determine if the time is right for a periodic transfer */
263 	switch (qh->type) {
264 	case USB_ENDPOINT_XFER_ISOC:
265 	case USB_ENDPOINT_XFER_INT:
266 		DBG(3, "check whether there's still time for periodic Tx\n");
267 		frame = musb_readw(mbase, MUSB_FRAME);
268 		/* FIXME this doesn't implement that scheduling policy ...
269 		 * or handle framecounter wrapping
270 		 */
271 		if ((urb->transfer_flags & URB_ISO_ASAP)
272 				|| (frame >= urb->start_frame)) {
273 			/* REVISIT the SOF irq handler shouldn't duplicate
274 			 * this code; and we don't init urb->start_frame...
275 			 */
276 			qh->frame = 0;
277 			goto start;
278 		} else {
279 			qh->frame = urb->start_frame;
280 			/* enable SOF interrupt so we can count down */
281 			DBG(1, "SOF for %d\n", epnum);
282 #if 1 /* ifndef	CONFIG_ARCH_DAVINCI */
283 			musb_writeb(mbase, MUSB_INTRUSBE, 0xff);
284 #endif
285 		}
286 		break;
287 	default:
288 start:
289 		DBG(4, "Start TX%d %s\n", epnum,
290 			hw_ep->tx_channel ? "dma" : "pio");
291 
292 		if (!hw_ep->tx_channel)
293 			musb_h_tx_start(hw_ep);
294 		else if (is_cppi_enabled() || tusb_dma_omap())
295 			musb_h_tx_dma_start(hw_ep);
296 	}
297 }
298 
299 /* Context: caller owns controller lock, IRQs are blocked */
300 static void musb_giveback(struct musb *musb, struct urb *urb, int status)
301 __releases(musb->lock)
302 __acquires(musb->lock)
303 {
304 	DBG(({ int level; switch (status) {
305 				case 0:
306 					level = 4;
307 					break;
308 				/* common/boring faults */
309 				case -EREMOTEIO:
310 				case -ESHUTDOWN:
311 				case -ECONNRESET:
312 				case -EPIPE:
313 					level = 3;
314 					break;
315 				default:
316 					level = 2;
317 					break;
318 				}; level; }),
319 			"complete %p %pF (%d), dev%d ep%d%s, %d/%d\n",
320 			urb, urb->complete, status,
321 			usb_pipedevice(urb->pipe),
322 			usb_pipeendpoint(urb->pipe),
323 			usb_pipein(urb->pipe) ? "in" : "out",
324 			urb->actual_length, urb->transfer_buffer_length
325 			);
326 
327 	usb_hcd_unlink_urb_from_ep(musb_to_hcd(musb), urb);
328 	spin_unlock(&musb->lock);
329 	usb_hcd_giveback_urb(musb_to_hcd(musb), urb, status);
330 	spin_lock(&musb->lock);
331 }
332 
333 /* For bulk/interrupt endpoints only */
334 static inline void musb_save_toggle(struct musb_qh *qh, int is_in,
335 				    struct urb *urb)
336 {
337 	void __iomem		*epio = qh->hw_ep->regs;
338 	u16			csr;
339 
340 	/*
341 	 * FIXME: the current Mentor DMA code seems to have
342 	 * problems getting toggle correct.
343 	 */
344 
345 	if (is_in)
346 		csr = musb_readw(epio, MUSB_RXCSR) & MUSB_RXCSR_H_DATATOGGLE;
347 	else
348 		csr = musb_readw(epio, MUSB_TXCSR) & MUSB_TXCSR_H_DATATOGGLE;
349 
350 	usb_settoggle(urb->dev, qh->epnum, !is_in, csr ? 1 : 0);
351 }
352 
353 /*
354  * Advance this hardware endpoint's queue, completing the specified URB and
355  * advancing to either the next URB queued to that qh, or else invalidating
356  * that qh and advancing to the next qh scheduled after the current one.
357  *
358  * Context: caller owns controller lock, IRQs are blocked
359  */
360 static void musb_advance_schedule(struct musb *musb, struct urb *urb,
361 				  struct musb_hw_ep *hw_ep, int is_in)
362 {
363 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, is_in);
364 	struct musb_hw_ep	*ep = qh->hw_ep;
365 	int			ready = qh->is_ready;
366 	int			status;
367 
368 	status = (urb->status == -EINPROGRESS) ? 0 : urb->status;
369 
370 	/* save toggle eagerly, for paranoia */
371 	switch (qh->type) {
372 	case USB_ENDPOINT_XFER_BULK:
373 	case USB_ENDPOINT_XFER_INT:
374 		musb_save_toggle(qh, is_in, urb);
375 		break;
376 	case USB_ENDPOINT_XFER_ISOC:
377 		if (status == 0 && urb->error_count)
378 			status = -EXDEV;
379 		break;
380 	}
381 
382 	qh->is_ready = 0;
383 	musb_giveback(musb, urb, status);
384 	qh->is_ready = ready;
385 
386 	/* reclaim resources (and bandwidth) ASAP; deschedule it, and
387 	 * invalidate qh as soon as list_empty(&hep->urb_list)
388 	 */
389 	if (list_empty(&qh->hep->urb_list)) {
390 		struct list_head	*head;
391 
392 		if (is_in)
393 			ep->rx_reinit = 1;
394 		else
395 			ep->tx_reinit = 1;
396 
397 		/* Clobber old pointers to this qh */
398 		musb_ep_set_qh(ep, is_in, NULL);
399 		qh->hep->hcpriv = NULL;
400 
401 		switch (qh->type) {
402 
403 		case USB_ENDPOINT_XFER_CONTROL:
404 		case USB_ENDPOINT_XFER_BULK:
405 			/* fifo policy for these lists, except that NAKing
406 			 * should rotate a qh to the end (for fairness).
407 			 */
408 			if (qh->mux == 1) {
409 				head = qh->ring.prev;
410 				list_del(&qh->ring);
411 				kfree(qh);
412 				qh = first_qh(head);
413 				break;
414 			}
415 
416 		case USB_ENDPOINT_XFER_ISOC:
417 		case USB_ENDPOINT_XFER_INT:
418 			/* this is where periodic bandwidth should be
419 			 * de-allocated if it's tracked and allocated;
420 			 * and where we'd update the schedule tree...
421 			 */
422 			kfree(qh);
423 			qh = NULL;
424 			break;
425 		}
426 	}
427 
428 	if (qh != NULL && qh->is_ready) {
429 		DBG(4, "... next ep%d %cX urb %p\n",
430 		    hw_ep->epnum, is_in ? 'R' : 'T', next_urb(qh));
431 		musb_start_urb(musb, is_in, qh);
432 	}
433 }
434 
435 static u16 musb_h_flush_rxfifo(struct musb_hw_ep *hw_ep, u16 csr)
436 {
437 	/* we don't want fifo to fill itself again;
438 	 * ignore dma (various models),
439 	 * leave toggle alone (may not have been saved yet)
440 	 */
441 	csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_RXPKTRDY;
442 	csr &= ~(MUSB_RXCSR_H_REQPKT
443 		| MUSB_RXCSR_H_AUTOREQ
444 		| MUSB_RXCSR_AUTOCLEAR);
445 
446 	/* write 2x to allow double buffering */
447 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
448 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
449 
450 	/* flush writebuffer */
451 	return musb_readw(hw_ep->regs, MUSB_RXCSR);
452 }
453 
454 /*
455  * PIO RX for a packet (or part of it).
456  */
457 static bool
458 musb_host_packet_rx(struct musb *musb, struct urb *urb, u8 epnum, u8 iso_err)
459 {
460 	u16			rx_count;
461 	u8			*buf;
462 	u16			csr;
463 	bool			done = false;
464 	u32			length;
465 	int			do_flush = 0;
466 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
467 	void __iomem		*epio = hw_ep->regs;
468 	struct musb_qh		*qh = hw_ep->in_qh;
469 	int			pipe = urb->pipe;
470 	void			*buffer = urb->transfer_buffer;
471 
472 	/* musb_ep_select(mbase, epnum); */
473 	rx_count = musb_readw(epio, MUSB_RXCOUNT);
474 	DBG(3, "RX%d count %d, buffer %p len %d/%d\n", epnum, rx_count,
475 			urb->transfer_buffer, qh->offset,
476 			urb->transfer_buffer_length);
477 
478 	/* unload FIFO */
479 	if (usb_pipeisoc(pipe)) {
480 		int					status = 0;
481 		struct usb_iso_packet_descriptor	*d;
482 
483 		if (iso_err) {
484 			status = -EILSEQ;
485 			urb->error_count++;
486 		}
487 
488 		d = urb->iso_frame_desc + qh->iso_idx;
489 		buf = buffer + d->offset;
490 		length = d->length;
491 		if (rx_count > length) {
492 			if (status == 0) {
493 				status = -EOVERFLOW;
494 				urb->error_count++;
495 			}
496 			DBG(2, "** OVERFLOW %d into %d\n", rx_count, length);
497 			do_flush = 1;
498 		} else
499 			length = rx_count;
500 		urb->actual_length += length;
501 		d->actual_length = length;
502 
503 		d->status = status;
504 
505 		/* see if we are done */
506 		done = (++qh->iso_idx >= urb->number_of_packets);
507 	} else {
508 		/* non-isoch */
509 		buf = buffer + qh->offset;
510 		length = urb->transfer_buffer_length - qh->offset;
511 		if (rx_count > length) {
512 			if (urb->status == -EINPROGRESS)
513 				urb->status = -EOVERFLOW;
514 			DBG(2, "** OVERFLOW %d into %d\n", rx_count, length);
515 			do_flush = 1;
516 		} else
517 			length = rx_count;
518 		urb->actual_length += length;
519 		qh->offset += length;
520 
521 		/* see if we are done */
522 		done = (urb->actual_length == urb->transfer_buffer_length)
523 			|| (rx_count < qh->maxpacket)
524 			|| (urb->status != -EINPROGRESS);
525 		if (done
526 				&& (urb->status == -EINPROGRESS)
527 				&& (urb->transfer_flags & URB_SHORT_NOT_OK)
528 				&& (urb->actual_length
529 					< urb->transfer_buffer_length))
530 			urb->status = -EREMOTEIO;
531 	}
532 
533 	musb_read_fifo(hw_ep, length, buf);
534 
535 	csr = musb_readw(epio, MUSB_RXCSR);
536 	csr |= MUSB_RXCSR_H_WZC_BITS;
537 	if (unlikely(do_flush))
538 		musb_h_flush_rxfifo(hw_ep, csr);
539 	else {
540 		/* REVISIT this assumes AUTOCLEAR is never set */
541 		csr &= ~(MUSB_RXCSR_RXPKTRDY | MUSB_RXCSR_H_REQPKT);
542 		if (!done)
543 			csr |= MUSB_RXCSR_H_REQPKT;
544 		musb_writew(epio, MUSB_RXCSR, csr);
545 	}
546 
547 	return done;
548 }
549 
550 /* we don't always need to reinit a given side of an endpoint...
551  * when we do, use tx/rx reinit routine and then construct a new CSR
552  * to address data toggle, NYET, and DMA or PIO.
553  *
554  * it's possible that driver bugs (especially for DMA) or aborting a
555  * transfer might have left the endpoint busier than it should be.
556  * the busy/not-empty tests are basically paranoia.
557  */
558 static void
559 musb_rx_reinit(struct musb *musb, struct musb_qh *qh, struct musb_hw_ep *ep)
560 {
561 	u16	csr;
562 
563 	/* NOTE:  we know the "rx" fifo reinit never triggers for ep0.
564 	 * That always uses tx_reinit since ep0 repurposes TX register
565 	 * offsets; the initial SETUP packet is also a kind of OUT.
566 	 */
567 
568 	/* if programmed for Tx, put it in RX mode */
569 	if (ep->is_shared_fifo) {
570 		csr = musb_readw(ep->regs, MUSB_TXCSR);
571 		if (csr & MUSB_TXCSR_MODE) {
572 			musb_h_tx_flush_fifo(ep);
573 			csr = musb_readw(ep->regs, MUSB_TXCSR);
574 			musb_writew(ep->regs, MUSB_TXCSR,
575 				    csr | MUSB_TXCSR_FRCDATATOG);
576 		}
577 
578 		/*
579 		 * Clear the MODE bit (and everything else) to enable Rx.
580 		 * NOTE: we mustn't clear the DMAMODE bit before DMAENAB.
581 		 */
582 		if (csr & MUSB_TXCSR_DMAMODE)
583 			musb_writew(ep->regs, MUSB_TXCSR, MUSB_TXCSR_DMAMODE);
584 		musb_writew(ep->regs, MUSB_TXCSR, 0);
585 
586 	/* scrub all previous state, clearing toggle */
587 	} else {
588 		csr = musb_readw(ep->regs, MUSB_RXCSR);
589 		if (csr & MUSB_RXCSR_RXPKTRDY)
590 			WARNING("rx%d, packet/%d ready?\n", ep->epnum,
591 				musb_readw(ep->regs, MUSB_RXCOUNT));
592 
593 		musb_h_flush_rxfifo(ep, MUSB_RXCSR_CLRDATATOG);
594 	}
595 
596 	/* target addr and (for multipoint) hub addr/port */
597 	if (musb->is_multipoint) {
598 		musb_write_rxfunaddr(ep->target_regs, qh->addr_reg);
599 		musb_write_rxhubaddr(ep->target_regs, qh->h_addr_reg);
600 		musb_write_rxhubport(ep->target_regs, qh->h_port_reg);
601 
602 	} else
603 		musb_writeb(musb->mregs, MUSB_FADDR, qh->addr_reg);
604 
605 	/* protocol/endpoint, interval/NAKlimit, i/o size */
606 	musb_writeb(ep->regs, MUSB_RXTYPE, qh->type_reg);
607 	musb_writeb(ep->regs, MUSB_RXINTERVAL, qh->intv_reg);
608 	/* NOTE: bulk combining rewrites high bits of maxpacket */
609 	/* Set RXMAXP with the FIFO size of the endpoint
610 	 * to disable double buffer mode.
611 	 */
612 	if (musb->hwvers < MUSB_HWVERS_2000)
613 		musb_writew(ep->regs, MUSB_RXMAXP, ep->max_packet_sz_rx);
614 	else
615 		musb_writew(ep->regs, MUSB_RXMAXP,
616 				qh->maxpacket | ((qh->hb_mult - 1) << 11));
617 
618 	ep->rx_reinit = 0;
619 }
620 
621 static bool musb_tx_dma_program(struct dma_controller *dma,
622 		struct musb_hw_ep *hw_ep, struct musb_qh *qh,
623 		struct urb *urb, u32 offset, u32 length)
624 {
625 	struct dma_channel	*channel = hw_ep->tx_channel;
626 	void __iomem		*epio = hw_ep->regs;
627 	u16			pkt_size = qh->maxpacket;
628 	u16			csr;
629 	u8			mode;
630 
631 #ifdef	CONFIG_USB_INVENTRA_DMA
632 	if (length > channel->max_len)
633 		length = channel->max_len;
634 
635 	csr = musb_readw(epio, MUSB_TXCSR);
636 	if (length > pkt_size) {
637 		mode = 1;
638 		csr |= MUSB_TXCSR_DMAMODE | MUSB_TXCSR_DMAENAB;
639 		/* autoset shouldn't be set in high bandwidth */
640 		if (qh->hb_mult == 1)
641 			csr |= MUSB_TXCSR_AUTOSET;
642 	} else {
643 		mode = 0;
644 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAMODE);
645 		csr |= MUSB_TXCSR_DMAENAB; /* against programmer's guide */
646 	}
647 	channel->desired_mode = mode;
648 	musb_writew(epio, MUSB_TXCSR, csr);
649 #else
650 	if (!is_cppi_enabled() && !tusb_dma_omap())
651 		return false;
652 
653 	channel->actual_len = 0;
654 
655 	/*
656 	 * TX uses "RNDIS" mode automatically but needs help
657 	 * to identify the zero-length-final-packet case.
658 	 */
659 	mode = (urb->transfer_flags & URB_ZERO_PACKET) ? 1 : 0;
660 #endif
661 
662 	qh->segsize = length;
663 
664 	/*
665 	 * Ensure the data reaches to main memory before starting
666 	 * DMA transfer
667 	 */
668 	wmb();
669 
670 	if (!dma->channel_program(channel, pkt_size, mode,
671 			urb->transfer_dma + offset, length)) {
672 		dma->channel_release(channel);
673 		hw_ep->tx_channel = NULL;
674 
675 		csr = musb_readw(epio, MUSB_TXCSR);
676 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
677 		musb_writew(epio, MUSB_TXCSR, csr | MUSB_TXCSR_H_WZC_BITS);
678 		return false;
679 	}
680 	return true;
681 }
682 
683 /*
684  * Program an HDRC endpoint as per the given URB
685  * Context: irqs blocked, controller lock held
686  */
687 static void musb_ep_program(struct musb *musb, u8 epnum,
688 			struct urb *urb, int is_out,
689 			u8 *buf, u32 offset, u32 len)
690 {
691 	struct dma_controller	*dma_controller;
692 	struct dma_channel	*dma_channel;
693 	u8			dma_ok;
694 	void __iomem		*mbase = musb->mregs;
695 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
696 	void __iomem		*epio = hw_ep->regs;
697 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, !is_out);
698 	u16			packet_sz = qh->maxpacket;
699 
700 	DBG(3, "%s hw%d urb %p spd%d dev%d ep%d%s "
701 				"h_addr%02x h_port%02x bytes %d\n",
702 			is_out ? "-->" : "<--",
703 			epnum, urb, urb->dev->speed,
704 			qh->addr_reg, qh->epnum, is_out ? "out" : "in",
705 			qh->h_addr_reg, qh->h_port_reg,
706 			len);
707 
708 	musb_ep_select(mbase, epnum);
709 
710 	/* candidate for DMA? */
711 	dma_controller = musb->dma_controller;
712 	if (is_dma_capable() && epnum && dma_controller) {
713 		dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel;
714 		if (!dma_channel) {
715 			dma_channel = dma_controller->channel_alloc(
716 					dma_controller, hw_ep, is_out);
717 			if (is_out)
718 				hw_ep->tx_channel = dma_channel;
719 			else
720 				hw_ep->rx_channel = dma_channel;
721 		}
722 	} else
723 		dma_channel = NULL;
724 
725 	/* make sure we clear DMAEnab, autoSet bits from previous run */
726 
727 	/* OUT/transmit/EP0 or IN/receive? */
728 	if (is_out) {
729 		u16	csr;
730 		u16	int_txe;
731 		u16	load_count;
732 
733 		csr = musb_readw(epio, MUSB_TXCSR);
734 
735 		/* disable interrupt in case we flush */
736 		int_txe = musb_readw(mbase, MUSB_INTRTXE);
737 		musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
738 
739 		/* general endpoint setup */
740 		if (epnum) {
741 			/* flush all old state, set default */
742 			musb_h_tx_flush_fifo(hw_ep);
743 
744 			/*
745 			 * We must not clear the DMAMODE bit before or in
746 			 * the same cycle with the DMAENAB bit, so we clear
747 			 * the latter first...
748 			 */
749 			csr &= ~(MUSB_TXCSR_H_NAKTIMEOUT
750 					| MUSB_TXCSR_AUTOSET
751 					| MUSB_TXCSR_DMAENAB
752 					| MUSB_TXCSR_FRCDATATOG
753 					| MUSB_TXCSR_H_RXSTALL
754 					| MUSB_TXCSR_H_ERROR
755 					| MUSB_TXCSR_TXPKTRDY
756 					);
757 			csr |= MUSB_TXCSR_MODE;
758 
759 			if (usb_gettoggle(urb->dev, qh->epnum, 1))
760 				csr |= MUSB_TXCSR_H_WR_DATATOGGLE
761 					| MUSB_TXCSR_H_DATATOGGLE;
762 			else
763 				csr |= MUSB_TXCSR_CLRDATATOG;
764 
765 			musb_writew(epio, MUSB_TXCSR, csr);
766 			/* REVISIT may need to clear FLUSHFIFO ... */
767 			csr &= ~MUSB_TXCSR_DMAMODE;
768 			musb_writew(epio, MUSB_TXCSR, csr);
769 			csr = musb_readw(epio, MUSB_TXCSR);
770 		} else {
771 			/* endpoint 0: just flush */
772 			musb_h_ep0_flush_fifo(hw_ep);
773 		}
774 
775 		/* target addr and (for multipoint) hub addr/port */
776 		if (musb->is_multipoint) {
777 			musb_write_txfunaddr(mbase, epnum, qh->addr_reg);
778 			musb_write_txhubaddr(mbase, epnum, qh->h_addr_reg);
779 			musb_write_txhubport(mbase, epnum, qh->h_port_reg);
780 /* FIXME if !epnum, do the same for RX ... */
781 		} else
782 			musb_writeb(mbase, MUSB_FADDR, qh->addr_reg);
783 
784 		/* protocol/endpoint/interval/NAKlimit */
785 		if (epnum) {
786 			musb_writeb(epio, MUSB_TXTYPE, qh->type_reg);
787 			if (can_bulk_split(musb, qh->type))
788 				musb_writew(epio, MUSB_TXMAXP,
789 					packet_sz
790 					| ((hw_ep->max_packet_sz_tx /
791 						packet_sz) - 1) << 11);
792 			else
793 				musb_writew(epio, MUSB_TXMAXP,
794 					packet_sz);
795 			musb_writeb(epio, MUSB_TXINTERVAL, qh->intv_reg);
796 		} else {
797 			musb_writeb(epio, MUSB_NAKLIMIT0, qh->intv_reg);
798 			if (musb->is_multipoint)
799 				musb_writeb(epio, MUSB_TYPE0,
800 						qh->type_reg);
801 		}
802 
803 		if (can_bulk_split(musb, qh->type))
804 			load_count = min((u32) hw_ep->max_packet_sz_tx,
805 						len);
806 		else
807 			load_count = min((u32) packet_sz, len);
808 
809 		if (dma_channel && musb_tx_dma_program(dma_controller,
810 					hw_ep, qh, urb, offset, len))
811 			load_count = 0;
812 
813 		if (load_count) {
814 			/* PIO to load FIFO */
815 			qh->segsize = load_count;
816 			musb_write_fifo(hw_ep, load_count, buf);
817 		}
818 
819 		/* re-enable interrupt */
820 		musb_writew(mbase, MUSB_INTRTXE, int_txe);
821 
822 	/* IN/receive */
823 	} else {
824 		u16	csr;
825 
826 		if (hw_ep->rx_reinit) {
827 			musb_rx_reinit(musb, qh, hw_ep);
828 
829 			/* init new state: toggle and NYET, maybe DMA later */
830 			if (usb_gettoggle(urb->dev, qh->epnum, 0))
831 				csr = MUSB_RXCSR_H_WR_DATATOGGLE
832 					| MUSB_RXCSR_H_DATATOGGLE;
833 			else
834 				csr = 0;
835 			if (qh->type == USB_ENDPOINT_XFER_INT)
836 				csr |= MUSB_RXCSR_DISNYET;
837 
838 		} else {
839 			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
840 
841 			if (csr & (MUSB_RXCSR_RXPKTRDY
842 					| MUSB_RXCSR_DMAENAB
843 					| MUSB_RXCSR_H_REQPKT))
844 				ERR("broken !rx_reinit, ep%d csr %04x\n",
845 						hw_ep->epnum, csr);
846 
847 			/* scrub any stale state, leaving toggle alone */
848 			csr &= MUSB_RXCSR_DISNYET;
849 		}
850 
851 		/* kick things off */
852 
853 		if ((is_cppi_enabled() || tusb_dma_omap()) && dma_channel) {
854 			/* candidate for DMA */
855 			if (dma_channel) {
856 				dma_channel->actual_len = 0L;
857 				qh->segsize = len;
858 
859 				/* AUTOREQ is in a DMA register */
860 				musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
861 				csr = musb_readw(hw_ep->regs,
862 						MUSB_RXCSR);
863 
864 				/* unless caller treats short rx transfers as
865 				 * errors, we dare not queue multiple transfers.
866 				 */
867 				dma_ok = dma_controller->channel_program(
868 						dma_channel, packet_sz,
869 						!(urb->transfer_flags
870 							& URB_SHORT_NOT_OK),
871 						urb->transfer_dma + offset,
872 						qh->segsize);
873 				if (!dma_ok) {
874 					dma_controller->channel_release(
875 							dma_channel);
876 					hw_ep->rx_channel = NULL;
877 					dma_channel = NULL;
878 				} else
879 					csr |= MUSB_RXCSR_DMAENAB;
880 			}
881 		}
882 
883 		csr |= MUSB_RXCSR_H_REQPKT;
884 		DBG(7, "RXCSR%d := %04x\n", epnum, csr);
885 		musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
886 		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
887 	}
888 }
889 
890 
891 /*
892  * Service the default endpoint (ep0) as host.
893  * Return true until it's time to start the status stage.
894  */
895 static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
896 {
897 	bool			 more = false;
898 	u8			*fifo_dest = NULL;
899 	u16			fifo_count = 0;
900 	struct musb_hw_ep	*hw_ep = musb->control_ep;
901 	struct musb_qh		*qh = hw_ep->in_qh;
902 	struct usb_ctrlrequest	*request;
903 
904 	switch (musb->ep0_stage) {
905 	case MUSB_EP0_IN:
906 		fifo_dest = urb->transfer_buffer + urb->actual_length;
907 		fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
908 				   urb->actual_length);
909 		if (fifo_count < len)
910 			urb->status = -EOVERFLOW;
911 
912 		musb_read_fifo(hw_ep, fifo_count, fifo_dest);
913 
914 		urb->actual_length += fifo_count;
915 		if (len < qh->maxpacket) {
916 			/* always terminate on short read; it's
917 			 * rarely reported as an error.
918 			 */
919 		} else if (urb->actual_length <
920 				urb->transfer_buffer_length)
921 			more = true;
922 		break;
923 	case MUSB_EP0_START:
924 		request = (struct usb_ctrlrequest *) urb->setup_packet;
925 
926 		if (!request->wLength) {
927 			DBG(4, "start no-DATA\n");
928 			break;
929 		} else if (request->bRequestType & USB_DIR_IN) {
930 			DBG(4, "start IN-DATA\n");
931 			musb->ep0_stage = MUSB_EP0_IN;
932 			more = true;
933 			break;
934 		} else {
935 			DBG(4, "start OUT-DATA\n");
936 			musb->ep0_stage = MUSB_EP0_OUT;
937 			more = true;
938 		}
939 		/* FALLTHROUGH */
940 	case MUSB_EP0_OUT:
941 		fifo_count = min_t(size_t, qh->maxpacket,
942 				   urb->transfer_buffer_length -
943 				   urb->actual_length);
944 		if (fifo_count) {
945 			fifo_dest = (u8 *) (urb->transfer_buffer
946 					+ urb->actual_length);
947 			DBG(3, "Sending %d byte%s to ep0 fifo %p\n",
948 					fifo_count,
949 					(fifo_count == 1) ? "" : "s",
950 					fifo_dest);
951 			musb_write_fifo(hw_ep, fifo_count, fifo_dest);
952 
953 			urb->actual_length += fifo_count;
954 			more = true;
955 		}
956 		break;
957 	default:
958 		ERR("bogus ep0 stage %d\n", musb->ep0_stage);
959 		break;
960 	}
961 
962 	return more;
963 }
964 
965 /*
966  * Handle default endpoint interrupt as host. Only called in IRQ time
967  * from musb_interrupt().
968  *
969  * called with controller irqlocked
970  */
971 irqreturn_t musb_h_ep0_irq(struct musb *musb)
972 {
973 	struct urb		*urb;
974 	u16			csr, len;
975 	int			status = 0;
976 	void __iomem		*mbase = musb->mregs;
977 	struct musb_hw_ep	*hw_ep = musb->control_ep;
978 	void __iomem		*epio = hw_ep->regs;
979 	struct musb_qh		*qh = hw_ep->in_qh;
980 	bool			complete = false;
981 	irqreturn_t		retval = IRQ_NONE;
982 
983 	/* ep0 only has one queue, "in" */
984 	urb = next_urb(qh);
985 
986 	musb_ep_select(mbase, 0);
987 	csr = musb_readw(epio, MUSB_CSR0);
988 	len = (csr & MUSB_CSR0_RXPKTRDY)
989 			? musb_readb(epio, MUSB_COUNT0)
990 			: 0;
991 
992 	DBG(4, "<== csr0 %04x, qh %p, count %d, urb %p, stage %d\n",
993 		csr, qh, len, urb, musb->ep0_stage);
994 
995 	/* if we just did status stage, we are done */
996 	if (MUSB_EP0_STATUS == musb->ep0_stage) {
997 		retval = IRQ_HANDLED;
998 		complete = true;
999 	}
1000 
1001 	/* prepare status */
1002 	if (csr & MUSB_CSR0_H_RXSTALL) {
1003 		DBG(6, "STALLING ENDPOINT\n");
1004 		status = -EPIPE;
1005 
1006 	} else if (csr & MUSB_CSR0_H_ERROR) {
1007 		DBG(2, "no response, csr0 %04x\n", csr);
1008 		status = -EPROTO;
1009 
1010 	} else if (csr & MUSB_CSR0_H_NAKTIMEOUT) {
1011 		DBG(2, "control NAK timeout\n");
1012 
1013 		/* NOTE:  this code path would be a good place to PAUSE a
1014 		 * control transfer, if another one is queued, so that
1015 		 * ep0 is more likely to stay busy.  That's already done
1016 		 * for bulk RX transfers.
1017 		 *
1018 		 * if (qh->ring.next != &musb->control), then
1019 		 * we have a candidate... NAKing is *NOT* an error
1020 		 */
1021 		musb_writew(epio, MUSB_CSR0, 0);
1022 		retval = IRQ_HANDLED;
1023 	}
1024 
1025 	if (status) {
1026 		DBG(6, "aborting\n");
1027 		retval = IRQ_HANDLED;
1028 		if (urb)
1029 			urb->status = status;
1030 		complete = true;
1031 
1032 		/* use the proper sequence to abort the transfer */
1033 		if (csr & MUSB_CSR0_H_REQPKT) {
1034 			csr &= ~MUSB_CSR0_H_REQPKT;
1035 			musb_writew(epio, MUSB_CSR0, csr);
1036 			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1037 			musb_writew(epio, MUSB_CSR0, csr);
1038 		} else {
1039 			musb_h_ep0_flush_fifo(hw_ep);
1040 		}
1041 
1042 		musb_writeb(epio, MUSB_NAKLIMIT0, 0);
1043 
1044 		/* clear it */
1045 		musb_writew(epio, MUSB_CSR0, 0);
1046 	}
1047 
1048 	if (unlikely(!urb)) {
1049 		/* stop endpoint since we have no place for its data, this
1050 		 * SHOULD NEVER HAPPEN! */
1051 		ERR("no URB for end 0\n");
1052 
1053 		musb_h_ep0_flush_fifo(hw_ep);
1054 		goto done;
1055 	}
1056 
1057 	if (!complete) {
1058 		/* call common logic and prepare response */
1059 		if (musb_h_ep0_continue(musb, len, urb)) {
1060 			/* more packets required */
1061 			csr = (MUSB_EP0_IN == musb->ep0_stage)
1062 				?  MUSB_CSR0_H_REQPKT : MUSB_CSR0_TXPKTRDY;
1063 		} else {
1064 			/* data transfer complete; perform status phase */
1065 			if (usb_pipeout(urb->pipe)
1066 					|| !urb->transfer_buffer_length)
1067 				csr = MUSB_CSR0_H_STATUSPKT
1068 					| MUSB_CSR0_H_REQPKT;
1069 			else
1070 				csr = MUSB_CSR0_H_STATUSPKT
1071 					| MUSB_CSR0_TXPKTRDY;
1072 
1073 			/* flag status stage */
1074 			musb->ep0_stage = MUSB_EP0_STATUS;
1075 
1076 			DBG(5, "ep0 STATUS, csr %04x\n", csr);
1077 
1078 		}
1079 		musb_writew(epio, MUSB_CSR0, csr);
1080 		retval = IRQ_HANDLED;
1081 	} else
1082 		musb->ep0_stage = MUSB_EP0_IDLE;
1083 
1084 	/* call completion handler if done */
1085 	if (complete)
1086 		musb_advance_schedule(musb, urb, hw_ep, 1);
1087 done:
1088 	return retval;
1089 }
1090 
1091 
1092 #ifdef CONFIG_USB_INVENTRA_DMA
1093 
1094 /* Host side TX (OUT) using Mentor DMA works as follows:
1095 	submit_urb ->
1096 		- if queue was empty, Program Endpoint
1097 		- ... which starts DMA to fifo in mode 1 or 0
1098 
1099 	DMA Isr (transfer complete) -> TxAvail()
1100 		- Stop DMA (~DmaEnab)	(<--- Alert ... currently happens
1101 					only in musb_cleanup_urb)
1102 		- TxPktRdy has to be set in mode 0 or for
1103 			short packets in mode 1.
1104 */
1105 
1106 #endif
1107 
1108 /* Service a Tx-Available or dma completion irq for the endpoint */
1109 void musb_host_tx(struct musb *musb, u8 epnum)
1110 {
1111 	int			pipe;
1112 	bool			done = false;
1113 	u16			tx_csr;
1114 	size_t			length = 0;
1115 	size_t			offset = 0;
1116 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1117 	void __iomem		*epio = hw_ep->regs;
1118 	struct musb_qh		*qh = hw_ep->out_qh;
1119 	struct urb		*urb = next_urb(qh);
1120 	u32			status = 0;
1121 	void __iomem		*mbase = musb->mregs;
1122 	struct dma_channel	*dma;
1123 	bool			transfer_pending = false;
1124 
1125 	musb_ep_select(mbase, epnum);
1126 	tx_csr = musb_readw(epio, MUSB_TXCSR);
1127 
1128 	/* with CPPI, DMA sometimes triggers "extra" irqs */
1129 	if (!urb) {
1130 		DBG(4, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1131 		return;
1132 	}
1133 
1134 	pipe = urb->pipe;
1135 	dma = is_dma_capable() ? hw_ep->tx_channel : NULL;
1136 	DBG(4, "OUT/TX%d end, csr %04x%s\n", epnum, tx_csr,
1137 			dma ? ", dma" : "");
1138 
1139 	/* check for errors */
1140 	if (tx_csr & MUSB_TXCSR_H_RXSTALL) {
1141 		/* dma was disabled, fifo flushed */
1142 		DBG(3, "TX end %d stall\n", epnum);
1143 
1144 		/* stall; record URB status */
1145 		status = -EPIPE;
1146 
1147 	} else if (tx_csr & MUSB_TXCSR_H_ERROR) {
1148 		/* (NON-ISO) dma was disabled, fifo flushed */
1149 		DBG(3, "TX 3strikes on ep=%d\n", epnum);
1150 
1151 		status = -ETIMEDOUT;
1152 
1153 	} else if (tx_csr & MUSB_TXCSR_H_NAKTIMEOUT) {
1154 		DBG(6, "TX end=%d device not responding\n", epnum);
1155 
1156 		/* NOTE:  this code path would be a good place to PAUSE a
1157 		 * transfer, if there's some other (nonperiodic) tx urb
1158 		 * that could use this fifo.  (dma complicates it...)
1159 		 * That's already done for bulk RX transfers.
1160 		 *
1161 		 * if (bulk && qh->ring.next != &musb->out_bulk), then
1162 		 * we have a candidate... NAKing is *NOT* an error
1163 		 */
1164 		musb_ep_select(mbase, epnum);
1165 		musb_writew(epio, MUSB_TXCSR,
1166 				MUSB_TXCSR_H_WZC_BITS
1167 				| MUSB_TXCSR_TXPKTRDY);
1168 		return;
1169 	}
1170 
1171 	if (status) {
1172 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1173 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1174 			(void) musb->dma_controller->channel_abort(dma);
1175 		}
1176 
1177 		/* do the proper sequence to abort the transfer in the
1178 		 * usb core; the dma engine should already be stopped.
1179 		 */
1180 		musb_h_tx_flush_fifo(hw_ep);
1181 		tx_csr &= ~(MUSB_TXCSR_AUTOSET
1182 				| MUSB_TXCSR_DMAENAB
1183 				| MUSB_TXCSR_H_ERROR
1184 				| MUSB_TXCSR_H_RXSTALL
1185 				| MUSB_TXCSR_H_NAKTIMEOUT
1186 				);
1187 
1188 		musb_ep_select(mbase, epnum);
1189 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1190 		/* REVISIT may need to clear FLUSHFIFO ... */
1191 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1192 		musb_writeb(epio, MUSB_TXINTERVAL, 0);
1193 
1194 		done = true;
1195 	}
1196 
1197 	/* second cppi case */
1198 	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1199 		DBG(4, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1200 		return;
1201 	}
1202 
1203 	if (is_dma_capable() && dma && !status) {
1204 		/*
1205 		 * DMA has completed.  But if we're using DMA mode 1 (multi
1206 		 * packet DMA), we need a terminal TXPKTRDY interrupt before
1207 		 * we can consider this transfer completed, lest we trash
1208 		 * its last packet when writing the next URB's data.  So we
1209 		 * switch back to mode 0 to get that interrupt; we'll come
1210 		 * back here once it happens.
1211 		 */
1212 		if (tx_csr & MUSB_TXCSR_DMAMODE) {
1213 			/*
1214 			 * We shouldn't clear DMAMODE with DMAENAB set; so
1215 			 * clear them in a safe order.  That should be OK
1216 			 * once TXPKTRDY has been set (and I've never seen
1217 			 * it being 0 at this moment -- DMA interrupt latency
1218 			 * is significant) but if it hasn't been then we have
1219 			 * no choice but to stop being polite and ignore the
1220 			 * programmer's guide... :-)
1221 			 *
1222 			 * Note that we must write TXCSR with TXPKTRDY cleared
1223 			 * in order not to re-trigger the packet send (this bit
1224 			 * can't be cleared by CPU), and there's another caveat:
1225 			 * TXPKTRDY may be set shortly and then cleared in the
1226 			 * double-buffered FIFO mode, so we do an extra TXCSR
1227 			 * read for debouncing...
1228 			 */
1229 			tx_csr &= musb_readw(epio, MUSB_TXCSR);
1230 			if (tx_csr & MUSB_TXCSR_TXPKTRDY) {
1231 				tx_csr &= ~(MUSB_TXCSR_DMAENAB |
1232 					    MUSB_TXCSR_TXPKTRDY);
1233 				musb_writew(epio, MUSB_TXCSR,
1234 					    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1235 			}
1236 			tx_csr &= ~(MUSB_TXCSR_DMAMODE |
1237 				    MUSB_TXCSR_TXPKTRDY);
1238 			musb_writew(epio, MUSB_TXCSR,
1239 				    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1240 
1241 			/*
1242 			 * There is no guarantee that we'll get an interrupt
1243 			 * after clearing DMAMODE as we might have done this
1244 			 * too late (after TXPKTRDY was cleared by controller).
1245 			 * Re-read TXCSR as we have spoiled its previous value.
1246 			 */
1247 			tx_csr = musb_readw(epio, MUSB_TXCSR);
1248 		}
1249 
1250 		/*
1251 		 * We may get here from a DMA completion or TXPKTRDY interrupt.
1252 		 * In any case, we must check the FIFO status here and bail out
1253 		 * only if the FIFO still has data -- that should prevent the
1254 		 * "missed" TXPKTRDY interrupts and deal with double-buffered
1255 		 * FIFO mode too...
1256 		 */
1257 		if (tx_csr & (MUSB_TXCSR_FIFONOTEMPTY | MUSB_TXCSR_TXPKTRDY)) {
1258 			DBG(2, "DMA complete but packet still in FIFO, "
1259 			    "CSR %04x\n", tx_csr);
1260 			return;
1261 		}
1262 	}
1263 
1264 	if (!status || dma || usb_pipeisoc(pipe)) {
1265 		if (dma)
1266 			length = dma->actual_len;
1267 		else
1268 			length = qh->segsize;
1269 		qh->offset += length;
1270 
1271 		if (usb_pipeisoc(pipe)) {
1272 			struct usb_iso_packet_descriptor	*d;
1273 
1274 			d = urb->iso_frame_desc + qh->iso_idx;
1275 			d->actual_length = length;
1276 			d->status = status;
1277 			if (++qh->iso_idx >= urb->number_of_packets) {
1278 				done = true;
1279 			} else {
1280 				d++;
1281 				offset = d->offset;
1282 				length = d->length;
1283 			}
1284 		} else if (dma && urb->transfer_buffer_length == qh->offset) {
1285 			done = true;
1286 		} else {
1287 			/* see if we need to send more data, or ZLP */
1288 			if (qh->segsize < qh->maxpacket)
1289 				done = true;
1290 			else if (qh->offset == urb->transfer_buffer_length
1291 					&& !(urb->transfer_flags
1292 						& URB_ZERO_PACKET))
1293 				done = true;
1294 			if (!done) {
1295 				offset = qh->offset;
1296 				length = urb->transfer_buffer_length - offset;
1297 				transfer_pending = true;
1298 			}
1299 		}
1300 	}
1301 
1302 	/* urb->status != -EINPROGRESS means request has been faulted,
1303 	 * so we must abort this transfer after cleanup
1304 	 */
1305 	if (urb->status != -EINPROGRESS) {
1306 		done = true;
1307 		if (status == 0)
1308 			status = urb->status;
1309 	}
1310 
1311 	if (done) {
1312 		/* set status */
1313 		urb->status = status;
1314 		urb->actual_length = qh->offset;
1315 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_OUT);
1316 		return;
1317 	} else if ((usb_pipeisoc(pipe) || transfer_pending) && dma) {
1318 		if (musb_tx_dma_program(musb->dma_controller, hw_ep, qh, urb,
1319 				offset, length)) {
1320 			if (is_cppi_enabled() || tusb_dma_omap())
1321 				musb_h_tx_dma_start(hw_ep);
1322 			return;
1323 		}
1324 	} else	if (tx_csr & MUSB_TXCSR_DMAENAB) {
1325 		DBG(1, "not complete, but DMA enabled?\n");
1326 		return;
1327 	}
1328 
1329 	/*
1330 	 * PIO: start next packet in this URB.
1331 	 *
1332 	 * REVISIT: some docs say that when hw_ep->tx_double_buffered,
1333 	 * (and presumably, FIFO is not half-full) we should write *two*
1334 	 * packets before updating TXCSR; other docs disagree...
1335 	 */
1336 	if (length > qh->maxpacket)
1337 		length = qh->maxpacket;
1338 	/* Unmap the buffer so that CPU can use it */
1339 	unmap_urb_for_dma(musb_to_hcd(musb), urb);
1340 	musb_write_fifo(hw_ep, length, urb->transfer_buffer + offset);
1341 	qh->segsize = length;
1342 
1343 	musb_ep_select(mbase, epnum);
1344 	musb_writew(epio, MUSB_TXCSR,
1345 			MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
1346 }
1347 
1348 
1349 #ifdef CONFIG_USB_INVENTRA_DMA
1350 
1351 /* Host side RX (IN) using Mentor DMA works as follows:
1352 	submit_urb ->
1353 		- if queue was empty, ProgramEndpoint
1354 		- first IN token is sent out (by setting ReqPkt)
1355 	LinuxIsr -> RxReady()
1356 	/\	=> first packet is received
1357 	|	- Set in mode 0 (DmaEnab, ~ReqPkt)
1358 	|		-> DMA Isr (transfer complete) -> RxReady()
1359 	|		    - Ack receive (~RxPktRdy), turn off DMA (~DmaEnab)
1360 	|		    - if urb not complete, send next IN token (ReqPkt)
1361 	|			   |		else complete urb.
1362 	|			   |
1363 	---------------------------
1364  *
1365  * Nuances of mode 1:
1366  *	For short packets, no ack (+RxPktRdy) is sent automatically
1367  *	(even if AutoClear is ON)
1368  *	For full packets, ack (~RxPktRdy) and next IN token (+ReqPkt) is sent
1369  *	automatically => major problem, as collecting the next packet becomes
1370  *	difficult. Hence mode 1 is not used.
1371  *
1372  * REVISIT
1373  *	All we care about at this driver level is that
1374  *       (a) all URBs terminate with REQPKT cleared and fifo(s) empty;
1375  *       (b) termination conditions are: short RX, or buffer full;
1376  *       (c) fault modes include
1377  *           - iff URB_SHORT_NOT_OK, short RX status is -EREMOTEIO.
1378  *             (and that endpoint's dma queue stops immediately)
1379  *           - overflow (full, PLUS more bytes in the terminal packet)
1380  *
1381  *	So for example, usb-storage sets URB_SHORT_NOT_OK, and would
1382  *	thus be a great candidate for using mode 1 ... for all but the
1383  *	last packet of one URB's transfer.
1384  */
1385 
1386 #endif
1387 
1388 /* Schedule next QH from musb->in_bulk and move the current qh to
1389  * the end; avoids starvation for other endpoints.
1390  */
1391 static void musb_bulk_rx_nak_timeout(struct musb *musb, struct musb_hw_ep *ep)
1392 {
1393 	struct dma_channel	*dma;
1394 	struct urb		*urb;
1395 	void __iomem		*mbase = musb->mregs;
1396 	void __iomem		*epio = ep->regs;
1397 	struct musb_qh		*cur_qh, *next_qh;
1398 	u16			rx_csr;
1399 
1400 	musb_ep_select(mbase, ep->epnum);
1401 	dma = is_dma_capable() ? ep->rx_channel : NULL;
1402 
1403 	/* clear nak timeout bit */
1404 	rx_csr = musb_readw(epio, MUSB_RXCSR);
1405 	rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1406 	rx_csr &= ~MUSB_RXCSR_DATAERROR;
1407 	musb_writew(epio, MUSB_RXCSR, rx_csr);
1408 
1409 	cur_qh = first_qh(&musb->in_bulk);
1410 	if (cur_qh) {
1411 		urb = next_urb(cur_qh);
1412 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1413 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1414 			musb->dma_controller->channel_abort(dma);
1415 			urb->actual_length += dma->actual_len;
1416 			dma->actual_len = 0L;
1417 		}
1418 		musb_save_toggle(cur_qh, 1, urb);
1419 
1420 		/* move cur_qh to end of queue */
1421 		list_move_tail(&cur_qh->ring, &musb->in_bulk);
1422 
1423 		/* get the next qh from musb->in_bulk */
1424 		next_qh = first_qh(&musb->in_bulk);
1425 
1426 		/* set rx_reinit and schedule the next qh */
1427 		ep->rx_reinit = 1;
1428 		musb_start_urb(musb, 1, next_qh);
1429 	}
1430 }
1431 
1432 /*
1433  * Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
1434  * and high-bandwidth IN transfer cases.
1435  */
1436 void musb_host_rx(struct musb *musb, u8 epnum)
1437 {
1438 	struct urb		*urb;
1439 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1440 	void __iomem		*epio = hw_ep->regs;
1441 	struct musb_qh		*qh = hw_ep->in_qh;
1442 	size_t			xfer_len;
1443 	void __iomem		*mbase = musb->mregs;
1444 	int			pipe;
1445 	u16			rx_csr, val;
1446 	bool			iso_err = false;
1447 	bool			done = false;
1448 	u32			status;
1449 	struct dma_channel	*dma;
1450 
1451 	musb_ep_select(mbase, epnum);
1452 
1453 	urb = next_urb(qh);
1454 	dma = is_dma_capable() ? hw_ep->rx_channel : NULL;
1455 	status = 0;
1456 	xfer_len = 0;
1457 
1458 	rx_csr = musb_readw(epio, MUSB_RXCSR);
1459 	val = rx_csr;
1460 
1461 	if (unlikely(!urb)) {
1462 		/* REVISIT -- THIS SHOULD NEVER HAPPEN ... but, at least
1463 		 * usbtest #11 (unlinks) triggers it regularly, sometimes
1464 		 * with fifo full.  (Only with DMA??)
1465 		 */
1466 		DBG(3, "BOGUS RX%d ready, csr %04x, count %d\n", epnum, val,
1467 			musb_readw(epio, MUSB_RXCOUNT));
1468 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1469 		return;
1470 	}
1471 
1472 	pipe = urb->pipe;
1473 
1474 	DBG(5, "<== hw %d rxcsr %04x, urb actual %d (+dma %zu)\n",
1475 		epnum, rx_csr, urb->actual_length,
1476 		dma ? dma->actual_len : 0);
1477 
1478 	/* check for errors, concurrent stall & unlink is not really
1479 	 * handled yet! */
1480 	if (rx_csr & MUSB_RXCSR_H_RXSTALL) {
1481 		DBG(3, "RX end %d STALL\n", epnum);
1482 
1483 		/* stall; record URB status */
1484 		status = -EPIPE;
1485 
1486 	} else if (rx_csr & MUSB_RXCSR_H_ERROR) {
1487 		DBG(3, "end %d RX proto error\n", epnum);
1488 
1489 		status = -EPROTO;
1490 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1491 
1492 	} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
1493 
1494 		if (USB_ENDPOINT_XFER_ISOC != qh->type) {
1495 			DBG(6, "RX end %d NAK timeout\n", epnum);
1496 
1497 			/* NOTE: NAKing is *NOT* an error, so we want to
1498 			 * continue.  Except ... if there's a request for
1499 			 * another QH, use that instead of starving it.
1500 			 *
1501 			 * Devices like Ethernet and serial adapters keep
1502 			 * reads posted at all times, which will starve
1503 			 * other devices without this logic.
1504 			 */
1505 			if (usb_pipebulk(urb->pipe)
1506 					&& qh->mux == 1
1507 					&& !list_is_singular(&musb->in_bulk)) {
1508 				musb_bulk_rx_nak_timeout(musb, hw_ep);
1509 				return;
1510 			}
1511 			musb_ep_select(mbase, epnum);
1512 			rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1513 			rx_csr &= ~MUSB_RXCSR_DATAERROR;
1514 			musb_writew(epio, MUSB_RXCSR, rx_csr);
1515 
1516 			goto finish;
1517 		} else {
1518 			DBG(4, "RX end %d ISO data error\n", epnum);
1519 			/* packet error reported later */
1520 			iso_err = true;
1521 		}
1522 	} else if (rx_csr & MUSB_RXCSR_INCOMPRX) {
1523 		DBG(3, "end %d high bandwidth incomplete ISO packet RX\n",
1524 				epnum);
1525 		status = -EPROTO;
1526 	}
1527 
1528 	/* faults abort the transfer */
1529 	if (status) {
1530 		/* clean up dma and collect transfer count */
1531 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1532 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1533 			(void) musb->dma_controller->channel_abort(dma);
1534 			xfer_len = dma->actual_len;
1535 		}
1536 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1537 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1538 		done = true;
1539 		goto finish;
1540 	}
1541 
1542 	if (unlikely(dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY)) {
1543 		/* SHOULD NEVER HAPPEN ... but at least DaVinci has done it */
1544 		ERR("RX%d dma busy, csr %04x\n", epnum, rx_csr);
1545 		goto finish;
1546 	}
1547 
1548 	/* thorough shutdown for now ... given more precise fault handling
1549 	 * and better queueing support, we might keep a DMA pipeline going
1550 	 * while processing this irq for earlier completions.
1551 	 */
1552 
1553 	/* FIXME this is _way_ too much in-line logic for Mentor DMA */
1554 
1555 #ifndef CONFIG_USB_INVENTRA_DMA
1556 	if (rx_csr & MUSB_RXCSR_H_REQPKT)  {
1557 		/* REVISIT this happened for a while on some short reads...
1558 		 * the cleanup still needs investigation... looks bad...
1559 		 * and also duplicates dma cleanup code above ... plus,
1560 		 * shouldn't this be the "half full" double buffer case?
1561 		 */
1562 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1563 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1564 			(void) musb->dma_controller->channel_abort(dma);
1565 			xfer_len = dma->actual_len;
1566 			done = true;
1567 		}
1568 
1569 		DBG(2, "RXCSR%d %04x, reqpkt, len %zu%s\n", epnum, rx_csr,
1570 				xfer_len, dma ? ", dma" : "");
1571 		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
1572 
1573 		musb_ep_select(mbase, epnum);
1574 		musb_writew(epio, MUSB_RXCSR,
1575 				MUSB_RXCSR_H_WZC_BITS | rx_csr);
1576 	}
1577 #endif
1578 	if (dma && (rx_csr & MUSB_RXCSR_DMAENAB)) {
1579 		xfer_len = dma->actual_len;
1580 
1581 		val &= ~(MUSB_RXCSR_DMAENAB
1582 			| MUSB_RXCSR_H_AUTOREQ
1583 			| MUSB_RXCSR_AUTOCLEAR
1584 			| MUSB_RXCSR_RXPKTRDY);
1585 		musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1586 
1587 #ifdef CONFIG_USB_INVENTRA_DMA
1588 		if (usb_pipeisoc(pipe)) {
1589 			struct usb_iso_packet_descriptor *d;
1590 
1591 			d = urb->iso_frame_desc + qh->iso_idx;
1592 			d->actual_length = xfer_len;
1593 
1594 			/* even if there was an error, we did the dma
1595 			 * for iso_frame_desc->length
1596 			 */
1597 			if (d->status != EILSEQ && d->status != -EOVERFLOW)
1598 				d->status = 0;
1599 
1600 			if (++qh->iso_idx >= urb->number_of_packets)
1601 				done = true;
1602 			else
1603 				done = false;
1604 
1605 		} else  {
1606 		/* done if urb buffer is full or short packet is recd */
1607 		done = (urb->actual_length + xfer_len >=
1608 				urb->transfer_buffer_length
1609 			|| dma->actual_len < qh->maxpacket);
1610 		}
1611 
1612 		/* send IN token for next packet, without AUTOREQ */
1613 		if (!done) {
1614 			val |= MUSB_RXCSR_H_REQPKT;
1615 			musb_writew(epio, MUSB_RXCSR,
1616 				MUSB_RXCSR_H_WZC_BITS | val);
1617 		}
1618 
1619 		DBG(4, "ep %d dma %s, rxcsr %04x, rxcount %d\n", epnum,
1620 			done ? "off" : "reset",
1621 			musb_readw(epio, MUSB_RXCSR),
1622 			musb_readw(epio, MUSB_RXCOUNT));
1623 #else
1624 		done = true;
1625 #endif
1626 	} else if (urb->status == -EINPROGRESS) {
1627 		/* if no errors, be sure a packet is ready for unloading */
1628 		if (unlikely(!(rx_csr & MUSB_RXCSR_RXPKTRDY))) {
1629 			status = -EPROTO;
1630 			ERR("Rx interrupt with no errors or packet!\n");
1631 
1632 			/* FIXME this is another "SHOULD NEVER HAPPEN" */
1633 
1634 /* SCRUB (RX) */
1635 			/* do the proper sequence to abort the transfer */
1636 			musb_ep_select(mbase, epnum);
1637 			val &= ~MUSB_RXCSR_H_REQPKT;
1638 			musb_writew(epio, MUSB_RXCSR, val);
1639 			goto finish;
1640 		}
1641 
1642 		/* we are expecting IN packets */
1643 #ifdef CONFIG_USB_INVENTRA_DMA
1644 		if (dma) {
1645 			struct dma_controller	*c;
1646 			u16			rx_count;
1647 			int			ret, length;
1648 			dma_addr_t		buf;
1649 
1650 			rx_count = musb_readw(epio, MUSB_RXCOUNT);
1651 
1652 			DBG(2, "RX%d count %d, buffer 0x%x len %d/%d\n",
1653 					epnum, rx_count,
1654 					urb->transfer_dma
1655 						+ urb->actual_length,
1656 					qh->offset,
1657 					urb->transfer_buffer_length);
1658 
1659 			c = musb->dma_controller;
1660 
1661 			if (usb_pipeisoc(pipe)) {
1662 				int d_status = 0;
1663 				struct usb_iso_packet_descriptor *d;
1664 
1665 				d = urb->iso_frame_desc + qh->iso_idx;
1666 
1667 				if (iso_err) {
1668 					d_status = -EILSEQ;
1669 					urb->error_count++;
1670 				}
1671 				if (rx_count > d->length) {
1672 					if (d_status == 0) {
1673 						d_status = -EOVERFLOW;
1674 						urb->error_count++;
1675 					}
1676 					DBG(2, "** OVERFLOW %d into %d\n",\
1677 					    rx_count, d->length);
1678 
1679 					length = d->length;
1680 				} else
1681 					length = rx_count;
1682 				d->status = d_status;
1683 				buf = urb->transfer_dma + d->offset;
1684 			} else {
1685 				length = rx_count;
1686 				buf = urb->transfer_dma +
1687 						urb->actual_length;
1688 			}
1689 
1690 			dma->desired_mode = 0;
1691 #ifdef USE_MODE1
1692 			/* because of the issue below, mode 1 will
1693 			 * only rarely behave with correct semantics.
1694 			 */
1695 			if ((urb->transfer_flags &
1696 						URB_SHORT_NOT_OK)
1697 				&& (urb->transfer_buffer_length -
1698 						urb->actual_length)
1699 					> qh->maxpacket)
1700 				dma->desired_mode = 1;
1701 			if (rx_count < hw_ep->max_packet_sz_rx) {
1702 				length = rx_count;
1703 				dma->desired_mode = 0;
1704 			} else {
1705 				length = urb->transfer_buffer_length;
1706 			}
1707 #endif
1708 
1709 /* Disadvantage of using mode 1:
1710  *	It's basically usable only for mass storage class; essentially all
1711  *	other protocols also terminate transfers on short packets.
1712  *
1713  * Details:
1714  *	An extra IN token is sent at the end of the transfer (due to AUTOREQ)
1715  *	If you try to use mode 1 for (transfer_buffer_length - 512), and try
1716  *	to use the extra IN token to grab the last packet using mode 0, then
1717  *	the problem is that you cannot be sure when the device will send the
1718  *	last packet and RxPktRdy set. Sometimes the packet is recd too soon
1719  *	such that it gets lost when RxCSR is re-set at the end of the mode 1
1720  *	transfer, while sometimes it is recd just a little late so that if you
1721  *	try to configure for mode 0 soon after the mode 1 transfer is
1722  *	completed, you will find rxcount 0. Okay, so you might think why not
1723  *	wait for an interrupt when the pkt is recd. Well, you won't get any!
1724  */
1725 
1726 			val = musb_readw(epio, MUSB_RXCSR);
1727 			val &= ~MUSB_RXCSR_H_REQPKT;
1728 
1729 			if (dma->desired_mode == 0)
1730 				val &= ~MUSB_RXCSR_H_AUTOREQ;
1731 			else
1732 				val |= MUSB_RXCSR_H_AUTOREQ;
1733 			val |= MUSB_RXCSR_DMAENAB;
1734 
1735 			/* autoclear shouldn't be set in high bandwidth */
1736 			if (qh->hb_mult == 1)
1737 				val |= MUSB_RXCSR_AUTOCLEAR;
1738 
1739 			musb_writew(epio, MUSB_RXCSR,
1740 				MUSB_RXCSR_H_WZC_BITS | val);
1741 
1742 			/* REVISIT if when actual_length != 0,
1743 			 * transfer_buffer_length needs to be
1744 			 * adjusted first...
1745 			 */
1746 			ret = c->channel_program(
1747 				dma, qh->maxpacket,
1748 				dma->desired_mode, buf, length);
1749 
1750 			if (!ret) {
1751 				c->channel_release(dma);
1752 				hw_ep->rx_channel = NULL;
1753 				dma = NULL;
1754 				/* REVISIT reset CSR */
1755 			}
1756 		}
1757 #endif	/* Mentor DMA */
1758 
1759 		if (!dma) {
1760 			/* Unmap the buffer so that CPU can use it */
1761 			unmap_urb_for_dma(musb_to_hcd(musb), urb);
1762 			done = musb_host_packet_rx(musb, urb,
1763 					epnum, iso_err);
1764 			DBG(6, "read %spacket\n", done ? "last " : "");
1765 		}
1766 	}
1767 
1768 finish:
1769 	urb->actual_length += xfer_len;
1770 	qh->offset += xfer_len;
1771 	if (done) {
1772 		if (urb->status == -EINPROGRESS)
1773 			urb->status = status;
1774 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_IN);
1775 	}
1776 }
1777 
1778 /* schedule nodes correspond to peripheral endpoints, like an OHCI QH.
1779  * the software schedule associates multiple such nodes with a given
1780  * host side hardware endpoint + direction; scheduling may activate
1781  * that hardware endpoint.
1782  */
1783 static int musb_schedule(
1784 	struct musb		*musb,
1785 	struct musb_qh		*qh,
1786 	int			is_in)
1787 {
1788 	int			idle;
1789 	int			best_diff;
1790 	int			best_end, epnum;
1791 	struct musb_hw_ep	*hw_ep = NULL;
1792 	struct list_head	*head = NULL;
1793 	u8			toggle;
1794 	u8			txtype;
1795 	struct urb		*urb = next_urb(qh);
1796 
1797 	/* use fixed hardware for control and bulk */
1798 	if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
1799 		head = &musb->control;
1800 		hw_ep = musb->control_ep;
1801 		goto success;
1802 	}
1803 
1804 	/* else, periodic transfers get muxed to other endpoints */
1805 
1806 	/*
1807 	 * We know this qh hasn't been scheduled, so all we need to do
1808 	 * is choose which hardware endpoint to put it on ...
1809 	 *
1810 	 * REVISIT what we really want here is a regular schedule tree
1811 	 * like e.g. OHCI uses.
1812 	 */
1813 	best_diff = 4096;
1814 	best_end = -1;
1815 
1816 	for (epnum = 1, hw_ep = musb->endpoints + 1;
1817 			epnum < musb->nr_endpoints;
1818 			epnum++, hw_ep++) {
1819 		int	diff;
1820 
1821 		if (musb_ep_get_qh(hw_ep, is_in) != NULL)
1822 			continue;
1823 
1824 		if (hw_ep == musb->bulk_ep)
1825 			continue;
1826 
1827 		if (is_in)
1828 			diff = hw_ep->max_packet_sz_rx;
1829 		else
1830 			diff = hw_ep->max_packet_sz_tx;
1831 		diff -= (qh->maxpacket * qh->hb_mult);
1832 
1833 		if (diff >= 0 && best_diff > diff) {
1834 
1835 			/*
1836 			 * Mentor controller has a bug in that if we schedule
1837 			 * a BULK Tx transfer on an endpoint that had earlier
1838 			 * handled ISOC then the BULK transfer has to start on
1839 			 * a zero toggle.  If the BULK transfer starts on a 1
1840 			 * toggle then this transfer will fail as the mentor
1841 			 * controller starts the Bulk transfer on a 0 toggle
1842 			 * irrespective of the programming of the toggle bits
1843 			 * in the TXCSR register.  Check for this condition
1844 			 * while allocating the EP for a Tx Bulk transfer.  If
1845 			 * so skip this EP.
1846 			 */
1847 			hw_ep = musb->endpoints + epnum;
1848 			toggle = usb_gettoggle(urb->dev, qh->epnum, !is_in);
1849 			txtype = (musb_readb(hw_ep->regs, MUSB_TXTYPE)
1850 					>> 4) & 0x3;
1851 			if (!is_in && (qh->type == USB_ENDPOINT_XFER_BULK) &&
1852 				toggle && (txtype == USB_ENDPOINT_XFER_ISOC))
1853 				continue;
1854 
1855 			best_diff = diff;
1856 			best_end = epnum;
1857 		}
1858 	}
1859 	/* use bulk reserved ep1 if no other ep is free */
1860 	if (best_end < 0 && qh->type == USB_ENDPOINT_XFER_BULK) {
1861 		hw_ep = musb->bulk_ep;
1862 		if (is_in)
1863 			head = &musb->in_bulk;
1864 		else
1865 			head = &musb->out_bulk;
1866 
1867 		/* Enable bulk RX NAK timeout scheme when bulk requests are
1868 		 * multiplexed.  This scheme doen't work in high speed to full
1869 		 * speed scenario as NAK interrupts are not coming from a
1870 		 * full speed device connected to a high speed device.
1871 		 * NAK timeout interval is 8 (128 uframe or 16ms) for HS and
1872 		 * 4 (8 frame or 8ms) for FS device.
1873 		 */
1874 		if (is_in && qh->dev)
1875 			qh->intv_reg =
1876 				(USB_SPEED_HIGH == qh->dev->speed) ? 8 : 4;
1877 		goto success;
1878 	} else if (best_end < 0) {
1879 		return -ENOSPC;
1880 	}
1881 
1882 	idle = 1;
1883 	qh->mux = 0;
1884 	hw_ep = musb->endpoints + best_end;
1885 	DBG(4, "qh %p periodic slot %d\n", qh, best_end);
1886 success:
1887 	if (head) {
1888 		idle = list_empty(head);
1889 		list_add_tail(&qh->ring, head);
1890 		qh->mux = 1;
1891 	}
1892 	qh->hw_ep = hw_ep;
1893 	qh->hep->hcpriv = qh;
1894 	if (idle)
1895 		musb_start_urb(musb, is_in, qh);
1896 	return 0;
1897 }
1898 
1899 static int musb_urb_enqueue(
1900 	struct usb_hcd			*hcd,
1901 	struct urb			*urb,
1902 	gfp_t				mem_flags)
1903 {
1904 	unsigned long			flags;
1905 	struct musb			*musb = hcd_to_musb(hcd);
1906 	struct usb_host_endpoint	*hep = urb->ep;
1907 	struct musb_qh			*qh;
1908 	struct usb_endpoint_descriptor	*epd = &hep->desc;
1909 	int				ret;
1910 	unsigned			type_reg;
1911 	unsigned			interval;
1912 
1913 	/* host role must be active */
1914 	if (!is_host_active(musb) || !musb->is_active)
1915 		return -ENODEV;
1916 
1917 	spin_lock_irqsave(&musb->lock, flags);
1918 	ret = usb_hcd_link_urb_to_ep(hcd, urb);
1919 	qh = ret ? NULL : hep->hcpriv;
1920 	if (qh)
1921 		urb->hcpriv = qh;
1922 	spin_unlock_irqrestore(&musb->lock, flags);
1923 
1924 	/* DMA mapping was already done, if needed, and this urb is on
1925 	 * hep->urb_list now ... so we're done, unless hep wasn't yet
1926 	 * scheduled onto a live qh.
1927 	 *
1928 	 * REVISIT best to keep hep->hcpriv valid until the endpoint gets
1929 	 * disabled, testing for empty qh->ring and avoiding qh setup costs
1930 	 * except for the first urb queued after a config change.
1931 	 */
1932 	if (qh || ret)
1933 		return ret;
1934 
1935 	/* Allocate and initialize qh, minimizing the work done each time
1936 	 * hw_ep gets reprogrammed, or with irqs blocked.  Then schedule it.
1937 	 *
1938 	 * REVISIT consider a dedicated qh kmem_cache, so it's harder
1939 	 * for bugs in other kernel code to break this driver...
1940 	 */
1941 	qh = kzalloc(sizeof *qh, mem_flags);
1942 	if (!qh) {
1943 		spin_lock_irqsave(&musb->lock, flags);
1944 		usb_hcd_unlink_urb_from_ep(hcd, urb);
1945 		spin_unlock_irqrestore(&musb->lock, flags);
1946 		return -ENOMEM;
1947 	}
1948 
1949 	qh->hep = hep;
1950 	qh->dev = urb->dev;
1951 	INIT_LIST_HEAD(&qh->ring);
1952 	qh->is_ready = 1;
1953 
1954 	qh->maxpacket = le16_to_cpu(epd->wMaxPacketSize);
1955 	qh->type = usb_endpoint_type(epd);
1956 
1957 	/* Bits 11 & 12 of wMaxPacketSize encode high bandwidth multiplier.
1958 	 * Some musb cores don't support high bandwidth ISO transfers; and
1959 	 * we don't (yet!) support high bandwidth interrupt transfers.
1960 	 */
1961 	qh->hb_mult = 1 + ((qh->maxpacket >> 11) & 0x03);
1962 	if (qh->hb_mult > 1) {
1963 		int ok = (qh->type == USB_ENDPOINT_XFER_ISOC);
1964 
1965 		if (ok)
1966 			ok = (usb_pipein(urb->pipe) && musb->hb_iso_rx)
1967 				|| (usb_pipeout(urb->pipe) && musb->hb_iso_tx);
1968 		if (!ok) {
1969 			ret = -EMSGSIZE;
1970 			goto done;
1971 		}
1972 		qh->maxpacket &= 0x7ff;
1973 	}
1974 
1975 	qh->epnum = usb_endpoint_num(epd);
1976 
1977 	/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
1978 	qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
1979 
1980 	/* precompute rxtype/txtype/type0 register */
1981 	type_reg = (qh->type << 4) | qh->epnum;
1982 	switch (urb->dev->speed) {
1983 	case USB_SPEED_LOW:
1984 		type_reg |= 0xc0;
1985 		break;
1986 	case USB_SPEED_FULL:
1987 		type_reg |= 0x80;
1988 		break;
1989 	default:
1990 		type_reg |= 0x40;
1991 	}
1992 	qh->type_reg = type_reg;
1993 
1994 	/* Precompute RXINTERVAL/TXINTERVAL register */
1995 	switch (qh->type) {
1996 	case USB_ENDPOINT_XFER_INT:
1997 		/*
1998 		 * Full/low speeds use the  linear encoding,
1999 		 * high speed uses the logarithmic encoding.
2000 		 */
2001 		if (urb->dev->speed <= USB_SPEED_FULL) {
2002 			interval = max_t(u8, epd->bInterval, 1);
2003 			break;
2004 		}
2005 		/* FALLTHROUGH */
2006 	case USB_ENDPOINT_XFER_ISOC:
2007 		/* ISO always uses logarithmic encoding */
2008 		interval = min_t(u8, epd->bInterval, 16);
2009 		break;
2010 	default:
2011 		/* REVISIT we actually want to use NAK limits, hinting to the
2012 		 * transfer scheduling logic to try some other qh, e.g. try
2013 		 * for 2 msec first:
2014 		 *
2015 		 * interval = (USB_SPEED_HIGH == urb->dev->speed) ? 16 : 2;
2016 		 *
2017 		 * The downside of disabling this is that transfer scheduling
2018 		 * gets VERY unfair for nonperiodic transfers; a misbehaving
2019 		 * peripheral could make that hurt.  That's perfectly normal
2020 		 * for reads from network or serial adapters ... so we have
2021 		 * partial NAKlimit support for bulk RX.
2022 		 *
2023 		 * The upside of disabling it is simpler transfer scheduling.
2024 		 */
2025 		interval = 0;
2026 	}
2027 	qh->intv_reg = interval;
2028 
2029 	/* precompute addressing for external hub/tt ports */
2030 	if (musb->is_multipoint) {
2031 		struct usb_device	*parent = urb->dev->parent;
2032 
2033 		if (parent != hcd->self.root_hub) {
2034 			qh->h_addr_reg = (u8) parent->devnum;
2035 
2036 			/* set up tt info if needed */
2037 			if (urb->dev->tt) {
2038 				qh->h_port_reg = (u8) urb->dev->ttport;
2039 				if (urb->dev->tt->hub)
2040 					qh->h_addr_reg =
2041 						(u8) urb->dev->tt->hub->devnum;
2042 				if (urb->dev->tt->multi)
2043 					qh->h_addr_reg |= 0x80;
2044 			}
2045 		}
2046 	}
2047 
2048 	/* invariant: hep->hcpriv is null OR the qh that's already scheduled.
2049 	 * until we get real dma queues (with an entry for each urb/buffer),
2050 	 * we only have work to do in the former case.
2051 	 */
2052 	spin_lock_irqsave(&musb->lock, flags);
2053 	if (hep->hcpriv) {
2054 		/* some concurrent activity submitted another urb to hep...
2055 		 * odd, rare, error prone, but legal.
2056 		 */
2057 		kfree(qh);
2058 		qh = NULL;
2059 		ret = 0;
2060 	} else
2061 		ret = musb_schedule(musb, qh,
2062 				epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK);
2063 
2064 	if (ret == 0) {
2065 		urb->hcpriv = qh;
2066 		/* FIXME set urb->start_frame for iso/intr, it's tested in
2067 		 * musb_start_urb(), but otherwise only konicawc cares ...
2068 		 */
2069 	}
2070 	spin_unlock_irqrestore(&musb->lock, flags);
2071 
2072 done:
2073 	if (ret != 0) {
2074 		spin_lock_irqsave(&musb->lock, flags);
2075 		usb_hcd_unlink_urb_from_ep(hcd, urb);
2076 		spin_unlock_irqrestore(&musb->lock, flags);
2077 		kfree(qh);
2078 	}
2079 	return ret;
2080 }
2081 
2082 
2083 /*
2084  * abort a transfer that's at the head of a hardware queue.
2085  * called with controller locked, irqs blocked
2086  * that hardware queue advances to the next transfer, unless prevented
2087  */
2088 static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh)
2089 {
2090 	struct musb_hw_ep	*ep = qh->hw_ep;
2091 	void __iomem		*epio = ep->regs;
2092 	unsigned		hw_end = ep->epnum;
2093 	void __iomem		*regs = ep->musb->mregs;
2094 	int			is_in = usb_pipein(urb->pipe);
2095 	int			status = 0;
2096 	u16			csr;
2097 
2098 	musb_ep_select(regs, hw_end);
2099 
2100 	if (is_dma_capable()) {
2101 		struct dma_channel	*dma;
2102 
2103 		dma = is_in ? ep->rx_channel : ep->tx_channel;
2104 		if (dma) {
2105 			status = ep->musb->dma_controller->channel_abort(dma);
2106 			DBG(status ? 1 : 3,
2107 				"abort %cX%d DMA for urb %p --> %d\n",
2108 				is_in ? 'R' : 'T', ep->epnum,
2109 				urb, status);
2110 			urb->actual_length += dma->actual_len;
2111 		}
2112 	}
2113 
2114 	/* turn off DMA requests, discard state, stop polling ... */
2115 	if (is_in) {
2116 		/* giveback saves bulk toggle */
2117 		csr = musb_h_flush_rxfifo(ep, 0);
2118 
2119 		/* REVISIT we still get an irq; should likely clear the
2120 		 * endpoint's irq status here to avoid bogus irqs.
2121 		 * clearing that status is platform-specific...
2122 		 */
2123 	} else if (ep->epnum) {
2124 		musb_h_tx_flush_fifo(ep);
2125 		csr = musb_readw(epio, MUSB_TXCSR);
2126 		csr &= ~(MUSB_TXCSR_AUTOSET
2127 			| MUSB_TXCSR_DMAENAB
2128 			| MUSB_TXCSR_H_RXSTALL
2129 			| MUSB_TXCSR_H_NAKTIMEOUT
2130 			| MUSB_TXCSR_H_ERROR
2131 			| MUSB_TXCSR_TXPKTRDY);
2132 		musb_writew(epio, MUSB_TXCSR, csr);
2133 		/* REVISIT may need to clear FLUSHFIFO ... */
2134 		musb_writew(epio, MUSB_TXCSR, csr);
2135 		/* flush cpu writebuffer */
2136 		csr = musb_readw(epio, MUSB_TXCSR);
2137 	} else  {
2138 		musb_h_ep0_flush_fifo(ep);
2139 	}
2140 	if (status == 0)
2141 		musb_advance_schedule(ep->musb, urb, ep, is_in);
2142 	return status;
2143 }
2144 
2145 static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
2146 {
2147 	struct musb		*musb = hcd_to_musb(hcd);
2148 	struct musb_qh		*qh;
2149 	unsigned long		flags;
2150 	int			is_in  = usb_pipein(urb->pipe);
2151 	int			ret;
2152 
2153 	DBG(4, "urb=%p, dev%d ep%d%s\n", urb,
2154 			usb_pipedevice(urb->pipe),
2155 			usb_pipeendpoint(urb->pipe),
2156 			is_in ? "in" : "out");
2157 
2158 	spin_lock_irqsave(&musb->lock, flags);
2159 	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
2160 	if (ret)
2161 		goto done;
2162 
2163 	qh = urb->hcpriv;
2164 	if (!qh)
2165 		goto done;
2166 
2167 	/*
2168 	 * Any URB not actively programmed into endpoint hardware can be
2169 	 * immediately given back; that's any URB not at the head of an
2170 	 * endpoint queue, unless someday we get real DMA queues.  And even
2171 	 * if it's at the head, it might not be known to the hardware...
2172 	 *
2173 	 * Otherwise abort current transfer, pending DMA, etc.; urb->status
2174 	 * has already been updated.  This is a synchronous abort; it'd be
2175 	 * OK to hold off until after some IRQ, though.
2176 	 *
2177 	 * NOTE: qh is invalid unless !list_empty(&hep->urb_list)
2178 	 */
2179 	if (!qh->is_ready
2180 			|| urb->urb_list.prev != &qh->hep->urb_list
2181 			|| musb_ep_get_qh(qh->hw_ep, is_in) != qh) {
2182 		int	ready = qh->is_ready;
2183 
2184 		qh->is_ready = 0;
2185 		musb_giveback(musb, urb, 0);
2186 		qh->is_ready = ready;
2187 
2188 		/* If nothing else (usually musb_giveback) is using it
2189 		 * and its URB list has emptied, recycle this qh.
2190 		 */
2191 		if (ready && list_empty(&qh->hep->urb_list)) {
2192 			qh->hep->hcpriv = NULL;
2193 			list_del(&qh->ring);
2194 			kfree(qh);
2195 		}
2196 	} else
2197 		ret = musb_cleanup_urb(urb, qh);
2198 done:
2199 	spin_unlock_irqrestore(&musb->lock, flags);
2200 	return ret;
2201 }
2202 
2203 /* disable an endpoint */
2204 static void
2205 musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
2206 {
2207 	u8			is_in = hep->desc.bEndpointAddress & USB_DIR_IN;
2208 	unsigned long		flags;
2209 	struct musb		*musb = hcd_to_musb(hcd);
2210 	struct musb_qh		*qh;
2211 	struct urb		*urb;
2212 
2213 	spin_lock_irqsave(&musb->lock, flags);
2214 
2215 	qh = hep->hcpriv;
2216 	if (qh == NULL)
2217 		goto exit;
2218 
2219 	/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
2220 
2221 	/* Kick the first URB off the hardware, if needed */
2222 	qh->is_ready = 0;
2223 	if (musb_ep_get_qh(qh->hw_ep, is_in) == qh) {
2224 		urb = next_urb(qh);
2225 
2226 		/* make software (then hardware) stop ASAP */
2227 		if (!urb->unlinked)
2228 			urb->status = -ESHUTDOWN;
2229 
2230 		/* cleanup */
2231 		musb_cleanup_urb(urb, qh);
2232 
2233 		/* Then nuke all the others ... and advance the
2234 		 * queue on hw_ep (e.g. bulk ring) when we're done.
2235 		 */
2236 		while (!list_empty(&hep->urb_list)) {
2237 			urb = next_urb(qh);
2238 			urb->status = -ESHUTDOWN;
2239 			musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
2240 		}
2241 	} else {
2242 		/* Just empty the queue; the hardware is busy with
2243 		 * other transfers, and since !qh->is_ready nothing
2244 		 * will activate any of these as it advances.
2245 		 */
2246 		while (!list_empty(&hep->urb_list))
2247 			musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
2248 
2249 		hep->hcpriv = NULL;
2250 		list_del(&qh->ring);
2251 		kfree(qh);
2252 	}
2253 exit:
2254 	spin_unlock_irqrestore(&musb->lock, flags);
2255 }
2256 
2257 static int musb_h_get_frame_number(struct usb_hcd *hcd)
2258 {
2259 	struct musb	*musb = hcd_to_musb(hcd);
2260 
2261 	return musb_readw(musb->mregs, MUSB_FRAME);
2262 }
2263 
2264 static int musb_h_start(struct usb_hcd *hcd)
2265 {
2266 	struct musb	*musb = hcd_to_musb(hcd);
2267 
2268 	/* NOTE: musb_start() is called when the hub driver turns
2269 	 * on port power, or when (OTG) peripheral starts.
2270 	 */
2271 	hcd->state = HC_STATE_RUNNING;
2272 	musb->port1_status = 0;
2273 	return 0;
2274 }
2275 
2276 static void musb_h_stop(struct usb_hcd *hcd)
2277 {
2278 	musb_stop(hcd_to_musb(hcd));
2279 	hcd->state = HC_STATE_HALT;
2280 }
2281 
2282 static int musb_bus_suspend(struct usb_hcd *hcd)
2283 {
2284 	struct musb	*musb = hcd_to_musb(hcd);
2285 	u8		devctl;
2286 
2287 	if (!is_host_active(musb))
2288 		return 0;
2289 
2290 	switch (musb->xceiv->state) {
2291 	case OTG_STATE_A_SUSPEND:
2292 		return 0;
2293 	case OTG_STATE_A_WAIT_VRISE:
2294 		/* ID could be grounded even if there's no device
2295 		 * on the other end of the cable.  NOTE that the
2296 		 * A_WAIT_VRISE timers are messy with MUSB...
2297 		 */
2298 		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2299 		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2300 			musb->xceiv->state = OTG_STATE_A_WAIT_BCON;
2301 		break;
2302 	default:
2303 		break;
2304 	}
2305 
2306 	if (musb->is_active) {
2307 		WARNING("trying to suspend as %s while active\n",
2308 				otg_state_string(musb));
2309 		return -EBUSY;
2310 	} else
2311 		return 0;
2312 }
2313 
2314 static int musb_bus_resume(struct usb_hcd *hcd)
2315 {
2316 	/* resuming child port does the work */
2317 	return 0;
2318 }
2319 
2320 const struct hc_driver musb_hc_driver = {
2321 	.description		= "musb-hcd",
2322 	.product_desc		= "MUSB HDRC host driver",
2323 	.hcd_priv_size		= sizeof(struct musb),
2324 	.flags			= HCD_USB2 | HCD_MEMORY,
2325 
2326 	/* not using irq handler or reset hooks from usbcore, since
2327 	 * those must be shared with peripheral code for OTG configs
2328 	 */
2329 
2330 	.start			= musb_h_start,
2331 	.stop			= musb_h_stop,
2332 
2333 	.get_frame_number	= musb_h_get_frame_number,
2334 
2335 	.urb_enqueue		= musb_urb_enqueue,
2336 	.urb_dequeue		= musb_urb_dequeue,
2337 	.endpoint_disable	= musb_h_disable,
2338 
2339 	.hub_status_data	= musb_hub_status_data,
2340 	.hub_control		= musb_hub_control,
2341 	.bus_suspend		= musb_bus_suspend,
2342 	.bus_resume		= musb_bus_resume,
2343 	/* .start_port_reset	= NULL, */
2344 	/* .hub_irq_enable	= NULL, */
2345 };
2346