xref: /openbmc/linux/drivers/usb/musb/musb_host.c (revision 3a9a231d)
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 	struct musb	*musb = ep->musb;
110 	void __iomem	*epio = ep->regs;
111 	u16		csr;
112 	u16		lastcsr = 0;
113 	int		retries = 1000;
114 
115 	csr = musb_readw(epio, MUSB_TXCSR);
116 	while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
117 		if (csr != lastcsr)
118 			dev_dbg(musb->controller, "Host TX FIFONOTEMPTY csr: %02x\n", csr);
119 		lastcsr = csr;
120 		csr |= MUSB_TXCSR_FLUSHFIFO;
121 		musb_writew(epio, MUSB_TXCSR, csr);
122 		csr = musb_readw(epio, MUSB_TXCSR);
123 		if (WARN(retries-- < 1,
124 				"Could not flush host TX%d fifo: csr: %04x\n",
125 				ep->epnum, csr))
126 			return;
127 		mdelay(1);
128 	}
129 }
130 
131 static void musb_h_ep0_flush_fifo(struct musb_hw_ep *ep)
132 {
133 	void __iomem	*epio = ep->regs;
134 	u16		csr;
135 	int		retries = 5;
136 
137 	/* scrub any data left in the fifo */
138 	do {
139 		csr = musb_readw(epio, MUSB_TXCSR);
140 		if (!(csr & (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_RXPKTRDY)))
141 			break;
142 		musb_writew(epio, MUSB_TXCSR, MUSB_CSR0_FLUSHFIFO);
143 		csr = musb_readw(epio, MUSB_TXCSR);
144 		udelay(10);
145 	} while (--retries);
146 
147 	WARN(!retries, "Could not flush host TX%d fifo: csr: %04x\n",
148 			ep->epnum, csr);
149 
150 	/* and reset for the next transfer */
151 	musb_writew(epio, MUSB_TXCSR, 0);
152 }
153 
154 /*
155  * Start transmit. Caller is responsible for locking shared resources.
156  * musb must be locked.
157  */
158 static inline void musb_h_tx_start(struct musb_hw_ep *ep)
159 {
160 	u16	txcsr;
161 
162 	/* NOTE: no locks here; caller should lock and select EP */
163 	if (ep->epnum) {
164 		txcsr = musb_readw(ep->regs, MUSB_TXCSR);
165 		txcsr |= MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_H_WZC_BITS;
166 		musb_writew(ep->regs, MUSB_TXCSR, txcsr);
167 	} else {
168 		txcsr = MUSB_CSR0_H_SETUPPKT | MUSB_CSR0_TXPKTRDY;
169 		musb_writew(ep->regs, MUSB_CSR0, txcsr);
170 	}
171 
172 }
173 
174 static inline void musb_h_tx_dma_start(struct musb_hw_ep *ep)
175 {
176 	u16	txcsr;
177 
178 	/* NOTE: no locks here; caller should lock and select EP */
179 	txcsr = musb_readw(ep->regs, MUSB_TXCSR);
180 	txcsr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_H_WZC_BITS;
181 	if (is_cppi_enabled())
182 		txcsr |= MUSB_TXCSR_DMAMODE;
183 	musb_writew(ep->regs, MUSB_TXCSR, txcsr);
184 }
185 
186 static void musb_ep_set_qh(struct musb_hw_ep *ep, int is_in, struct musb_qh *qh)
187 {
188 	if (is_in != 0 || ep->is_shared_fifo)
189 		ep->in_qh  = qh;
190 	if (is_in == 0 || ep->is_shared_fifo)
191 		ep->out_qh = qh;
192 }
193 
194 static struct musb_qh *musb_ep_get_qh(struct musb_hw_ep *ep, int is_in)
195 {
196 	return is_in ? ep->in_qh : ep->out_qh;
197 }
198 
199 /*
200  * Start the URB at the front of an endpoint's queue
201  * end must be claimed from the caller.
202  *
203  * Context: controller locked, irqs blocked
204  */
205 static void
206 musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
207 {
208 	u16			frame;
209 	u32			len;
210 	void __iomem		*mbase =  musb->mregs;
211 	struct urb		*urb = next_urb(qh);
212 	void			*buf = urb->transfer_buffer;
213 	u32			offset = 0;
214 	struct musb_hw_ep	*hw_ep = qh->hw_ep;
215 	unsigned		pipe = urb->pipe;
216 	u8			address = usb_pipedevice(pipe);
217 	int			epnum = hw_ep->epnum;
218 
219 	/* initialize software qh state */
220 	qh->offset = 0;
221 	qh->segsize = 0;
222 
223 	/* gather right source of data */
224 	switch (qh->type) {
225 	case USB_ENDPOINT_XFER_CONTROL:
226 		/* control transfers always start with SETUP */
227 		is_in = 0;
228 		musb->ep0_stage = MUSB_EP0_START;
229 		buf = urb->setup_packet;
230 		len = 8;
231 		break;
232 	case USB_ENDPOINT_XFER_ISOC:
233 		qh->iso_idx = 0;
234 		qh->frame = 0;
235 		offset = urb->iso_frame_desc[0].offset;
236 		len = urb->iso_frame_desc[0].length;
237 		break;
238 	default:		/* bulk, interrupt */
239 		/* actual_length may be nonzero on retry paths */
240 		buf = urb->transfer_buffer + urb->actual_length;
241 		len = urb->transfer_buffer_length - urb->actual_length;
242 	}
243 
244 	dev_dbg(musb->controller, "qh %p urb %p dev%d ep%d%s%s, hw_ep %d, %p/%d\n",
245 			qh, urb, address, qh->epnum,
246 			is_in ? "in" : "out",
247 			({char *s; switch (qh->type) {
248 			case USB_ENDPOINT_XFER_CONTROL:	s = ""; break;
249 			case USB_ENDPOINT_XFER_BULK:	s = "-bulk"; break;
250 			case USB_ENDPOINT_XFER_ISOC:	s = "-iso"; break;
251 			default:			s = "-intr"; break;
252 			}; s; }),
253 			epnum, buf + offset, len);
254 
255 	/* Configure endpoint */
256 	musb_ep_set_qh(hw_ep, is_in, qh);
257 	musb_ep_program(musb, epnum, urb, !is_in, buf, offset, len);
258 
259 	/* transmit may have more work: start it when it is time */
260 	if (is_in)
261 		return;
262 
263 	/* determine if the time is right for a periodic transfer */
264 	switch (qh->type) {
265 	case USB_ENDPOINT_XFER_ISOC:
266 	case USB_ENDPOINT_XFER_INT:
267 		dev_dbg(musb->controller, "check whether there's still time for periodic Tx\n");
268 		frame = musb_readw(mbase, MUSB_FRAME);
269 		/* FIXME this doesn't implement that scheduling policy ...
270 		 * or handle framecounter wrapping
271 		 */
272 		if ((urb->transfer_flags & URB_ISO_ASAP)
273 				|| (frame >= urb->start_frame)) {
274 			/* REVISIT the SOF irq handler shouldn't duplicate
275 			 * this code; and we don't init urb->start_frame...
276 			 */
277 			qh->frame = 0;
278 			goto start;
279 		} else {
280 			qh->frame = urb->start_frame;
281 			/* enable SOF interrupt so we can count down */
282 			dev_dbg(musb->controller, "SOF for %d\n", epnum);
283 #if 1 /* ifndef	CONFIG_ARCH_DAVINCI */
284 			musb_writeb(mbase, MUSB_INTRUSBE, 0xff);
285 #endif
286 		}
287 		break;
288 	default:
289 start:
290 		dev_dbg(musb->controller, "Start TX%d %s\n", epnum,
291 			hw_ep->tx_channel ? "dma" : "pio");
292 
293 		if (!hw_ep->tx_channel)
294 			musb_h_tx_start(hw_ep);
295 		else if (is_cppi_enabled() || tusb_dma_omap())
296 			musb_h_tx_dma_start(hw_ep);
297 	}
298 }
299 
300 /* Context: caller owns controller lock, IRQs are blocked */
301 static void musb_giveback(struct musb *musb, struct urb *urb, int status)
302 __releases(musb->lock)
303 __acquires(musb->lock)
304 {
305 	dev_dbg(musb->controller,
306 			"complete %p %pF (%d), dev%d ep%d%s, %d/%d\n",
307 			urb, urb->complete, status,
308 			usb_pipedevice(urb->pipe),
309 			usb_pipeendpoint(urb->pipe),
310 			usb_pipein(urb->pipe) ? "in" : "out",
311 			urb->actual_length, urb->transfer_buffer_length
312 			);
313 
314 	usb_hcd_unlink_urb_from_ep(musb_to_hcd(musb), urb);
315 	spin_unlock(&musb->lock);
316 	usb_hcd_giveback_urb(musb_to_hcd(musb), urb, status);
317 	spin_lock(&musb->lock);
318 }
319 
320 /* For bulk/interrupt endpoints only */
321 static inline void musb_save_toggle(struct musb_qh *qh, int is_in,
322 				    struct urb *urb)
323 {
324 	void __iomem		*epio = qh->hw_ep->regs;
325 	u16			csr;
326 
327 	/*
328 	 * FIXME: the current Mentor DMA code seems to have
329 	 * problems getting toggle correct.
330 	 */
331 
332 	if (is_in)
333 		csr = musb_readw(epio, MUSB_RXCSR) & MUSB_RXCSR_H_DATATOGGLE;
334 	else
335 		csr = musb_readw(epio, MUSB_TXCSR) & MUSB_TXCSR_H_DATATOGGLE;
336 
337 	usb_settoggle(urb->dev, qh->epnum, !is_in, csr ? 1 : 0);
338 }
339 
340 /*
341  * Advance this hardware endpoint's queue, completing the specified URB and
342  * advancing to either the next URB queued to that qh, or else invalidating
343  * that qh and advancing to the next qh scheduled after the current one.
344  *
345  * Context: caller owns controller lock, IRQs are blocked
346  */
347 static void musb_advance_schedule(struct musb *musb, struct urb *urb,
348 				  struct musb_hw_ep *hw_ep, int is_in)
349 {
350 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, is_in);
351 	struct musb_hw_ep	*ep = qh->hw_ep;
352 	int			ready = qh->is_ready;
353 	int			status;
354 
355 	status = (urb->status == -EINPROGRESS) ? 0 : urb->status;
356 
357 	/* save toggle eagerly, for paranoia */
358 	switch (qh->type) {
359 	case USB_ENDPOINT_XFER_BULK:
360 	case USB_ENDPOINT_XFER_INT:
361 		musb_save_toggle(qh, is_in, urb);
362 		break;
363 	case USB_ENDPOINT_XFER_ISOC:
364 		if (status == 0 && urb->error_count)
365 			status = -EXDEV;
366 		break;
367 	}
368 
369 	qh->is_ready = 0;
370 	musb_giveback(musb, urb, status);
371 	qh->is_ready = ready;
372 
373 	/* reclaim resources (and bandwidth) ASAP; deschedule it, and
374 	 * invalidate qh as soon as list_empty(&hep->urb_list)
375 	 */
376 	if (list_empty(&qh->hep->urb_list)) {
377 		struct list_head	*head;
378 
379 		if (is_in)
380 			ep->rx_reinit = 1;
381 		else
382 			ep->tx_reinit = 1;
383 
384 		/* Clobber old pointers to this qh */
385 		musb_ep_set_qh(ep, is_in, NULL);
386 		qh->hep->hcpriv = NULL;
387 
388 		switch (qh->type) {
389 
390 		case USB_ENDPOINT_XFER_CONTROL:
391 		case USB_ENDPOINT_XFER_BULK:
392 			/* fifo policy for these lists, except that NAKing
393 			 * should rotate a qh to the end (for fairness).
394 			 */
395 			if (qh->mux == 1) {
396 				head = qh->ring.prev;
397 				list_del(&qh->ring);
398 				kfree(qh);
399 				qh = first_qh(head);
400 				break;
401 			}
402 
403 		case USB_ENDPOINT_XFER_ISOC:
404 		case USB_ENDPOINT_XFER_INT:
405 			/* this is where periodic bandwidth should be
406 			 * de-allocated if it's tracked and allocated;
407 			 * and where we'd update the schedule tree...
408 			 */
409 			kfree(qh);
410 			qh = NULL;
411 			break;
412 		}
413 	}
414 
415 	if (qh != NULL && qh->is_ready) {
416 		dev_dbg(musb->controller, "... next ep%d %cX urb %p\n",
417 		    hw_ep->epnum, is_in ? 'R' : 'T', next_urb(qh));
418 		musb_start_urb(musb, is_in, qh);
419 	}
420 }
421 
422 static u16 musb_h_flush_rxfifo(struct musb_hw_ep *hw_ep, u16 csr)
423 {
424 	/* we don't want fifo to fill itself again;
425 	 * ignore dma (various models),
426 	 * leave toggle alone (may not have been saved yet)
427 	 */
428 	csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_RXPKTRDY;
429 	csr &= ~(MUSB_RXCSR_H_REQPKT
430 		| MUSB_RXCSR_H_AUTOREQ
431 		| MUSB_RXCSR_AUTOCLEAR);
432 
433 	/* write 2x to allow double buffering */
434 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
435 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
436 
437 	/* flush writebuffer */
438 	return musb_readw(hw_ep->regs, MUSB_RXCSR);
439 }
440 
441 /*
442  * PIO RX for a packet (or part of it).
443  */
444 static bool
445 musb_host_packet_rx(struct musb *musb, struct urb *urb, u8 epnum, u8 iso_err)
446 {
447 	u16			rx_count;
448 	u8			*buf;
449 	u16			csr;
450 	bool			done = false;
451 	u32			length;
452 	int			do_flush = 0;
453 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
454 	void __iomem		*epio = hw_ep->regs;
455 	struct musb_qh		*qh = hw_ep->in_qh;
456 	int			pipe = urb->pipe;
457 	void			*buffer = urb->transfer_buffer;
458 
459 	/* musb_ep_select(mbase, epnum); */
460 	rx_count = musb_readw(epio, MUSB_RXCOUNT);
461 	dev_dbg(musb->controller, "RX%d count %d, buffer %p len %d/%d\n", epnum, rx_count,
462 			urb->transfer_buffer, qh->offset,
463 			urb->transfer_buffer_length);
464 
465 	/* unload FIFO */
466 	if (usb_pipeisoc(pipe)) {
467 		int					status = 0;
468 		struct usb_iso_packet_descriptor	*d;
469 
470 		if (iso_err) {
471 			status = -EILSEQ;
472 			urb->error_count++;
473 		}
474 
475 		d = urb->iso_frame_desc + qh->iso_idx;
476 		buf = buffer + d->offset;
477 		length = d->length;
478 		if (rx_count > length) {
479 			if (status == 0) {
480 				status = -EOVERFLOW;
481 				urb->error_count++;
482 			}
483 			dev_dbg(musb->controller, "** OVERFLOW %d into %d\n", rx_count, length);
484 			do_flush = 1;
485 		} else
486 			length = rx_count;
487 		urb->actual_length += length;
488 		d->actual_length = length;
489 
490 		d->status = status;
491 
492 		/* see if we are done */
493 		done = (++qh->iso_idx >= urb->number_of_packets);
494 	} else {
495 		/* non-isoch */
496 		buf = buffer + qh->offset;
497 		length = urb->transfer_buffer_length - qh->offset;
498 		if (rx_count > length) {
499 			if (urb->status == -EINPROGRESS)
500 				urb->status = -EOVERFLOW;
501 			dev_dbg(musb->controller, "** OVERFLOW %d into %d\n", rx_count, length);
502 			do_flush = 1;
503 		} else
504 			length = rx_count;
505 		urb->actual_length += length;
506 		qh->offset += length;
507 
508 		/* see if we are done */
509 		done = (urb->actual_length == urb->transfer_buffer_length)
510 			|| (rx_count < qh->maxpacket)
511 			|| (urb->status != -EINPROGRESS);
512 		if (done
513 				&& (urb->status == -EINPROGRESS)
514 				&& (urb->transfer_flags & URB_SHORT_NOT_OK)
515 				&& (urb->actual_length
516 					< urb->transfer_buffer_length))
517 			urb->status = -EREMOTEIO;
518 	}
519 
520 	musb_read_fifo(hw_ep, length, buf);
521 
522 	csr = musb_readw(epio, MUSB_RXCSR);
523 	csr |= MUSB_RXCSR_H_WZC_BITS;
524 	if (unlikely(do_flush))
525 		musb_h_flush_rxfifo(hw_ep, csr);
526 	else {
527 		/* REVISIT this assumes AUTOCLEAR is never set */
528 		csr &= ~(MUSB_RXCSR_RXPKTRDY | MUSB_RXCSR_H_REQPKT);
529 		if (!done)
530 			csr |= MUSB_RXCSR_H_REQPKT;
531 		musb_writew(epio, MUSB_RXCSR, csr);
532 	}
533 
534 	return done;
535 }
536 
537 /* we don't always need to reinit a given side of an endpoint...
538  * when we do, use tx/rx reinit routine and then construct a new CSR
539  * to address data toggle, NYET, and DMA or PIO.
540  *
541  * it's possible that driver bugs (especially for DMA) or aborting a
542  * transfer might have left the endpoint busier than it should be.
543  * the busy/not-empty tests are basically paranoia.
544  */
545 static void
546 musb_rx_reinit(struct musb *musb, struct musb_qh *qh, struct musb_hw_ep *ep)
547 {
548 	u16	csr;
549 
550 	/* NOTE:  we know the "rx" fifo reinit never triggers for ep0.
551 	 * That always uses tx_reinit since ep0 repurposes TX register
552 	 * offsets; the initial SETUP packet is also a kind of OUT.
553 	 */
554 
555 	/* if programmed for Tx, put it in RX mode */
556 	if (ep->is_shared_fifo) {
557 		csr = musb_readw(ep->regs, MUSB_TXCSR);
558 		if (csr & MUSB_TXCSR_MODE) {
559 			musb_h_tx_flush_fifo(ep);
560 			csr = musb_readw(ep->regs, MUSB_TXCSR);
561 			musb_writew(ep->regs, MUSB_TXCSR,
562 				    csr | MUSB_TXCSR_FRCDATATOG);
563 		}
564 
565 		/*
566 		 * Clear the MODE bit (and everything else) to enable Rx.
567 		 * NOTE: we mustn't clear the DMAMODE bit before DMAENAB.
568 		 */
569 		if (csr & MUSB_TXCSR_DMAMODE)
570 			musb_writew(ep->regs, MUSB_TXCSR, MUSB_TXCSR_DMAMODE);
571 		musb_writew(ep->regs, MUSB_TXCSR, 0);
572 
573 	/* scrub all previous state, clearing toggle */
574 	} else {
575 		csr = musb_readw(ep->regs, MUSB_RXCSR);
576 		if (csr & MUSB_RXCSR_RXPKTRDY)
577 			WARNING("rx%d, packet/%d ready?\n", ep->epnum,
578 				musb_readw(ep->regs, MUSB_RXCOUNT));
579 
580 		musb_h_flush_rxfifo(ep, MUSB_RXCSR_CLRDATATOG);
581 	}
582 
583 	/* target addr and (for multipoint) hub addr/port */
584 	if (musb->is_multipoint) {
585 		musb_write_rxfunaddr(ep->target_regs, qh->addr_reg);
586 		musb_write_rxhubaddr(ep->target_regs, qh->h_addr_reg);
587 		musb_write_rxhubport(ep->target_regs, qh->h_port_reg);
588 
589 	} else
590 		musb_writeb(musb->mregs, MUSB_FADDR, qh->addr_reg);
591 
592 	/* protocol/endpoint, interval/NAKlimit, i/o size */
593 	musb_writeb(ep->regs, MUSB_RXTYPE, qh->type_reg);
594 	musb_writeb(ep->regs, MUSB_RXINTERVAL, qh->intv_reg);
595 	/* NOTE: bulk combining rewrites high bits of maxpacket */
596 	/* Set RXMAXP with the FIFO size of the endpoint
597 	 * to disable double buffer mode.
598 	 */
599 	if (musb->double_buffer_not_ok)
600 		musb_writew(ep->regs, MUSB_RXMAXP, ep->max_packet_sz_rx);
601 	else
602 		musb_writew(ep->regs, MUSB_RXMAXP,
603 				qh->maxpacket | ((qh->hb_mult - 1) << 11));
604 
605 	ep->rx_reinit = 0;
606 }
607 
608 static bool musb_tx_dma_program(struct dma_controller *dma,
609 		struct musb_hw_ep *hw_ep, struct musb_qh *qh,
610 		struct urb *urb, u32 offset, u32 length)
611 {
612 	struct dma_channel	*channel = hw_ep->tx_channel;
613 	void __iomem		*epio = hw_ep->regs;
614 	u16			pkt_size = qh->maxpacket;
615 	u16			csr;
616 	u8			mode;
617 
618 #ifdef	CONFIG_USB_INVENTRA_DMA
619 	if (length > channel->max_len)
620 		length = channel->max_len;
621 
622 	csr = musb_readw(epio, MUSB_TXCSR);
623 	if (length > pkt_size) {
624 		mode = 1;
625 		csr |= MUSB_TXCSR_DMAMODE | MUSB_TXCSR_DMAENAB;
626 		/* autoset shouldn't be set in high bandwidth */
627 		if (qh->hb_mult == 1)
628 			csr |= MUSB_TXCSR_AUTOSET;
629 	} else {
630 		mode = 0;
631 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAMODE);
632 		csr |= MUSB_TXCSR_DMAENAB; /* against programmer's guide */
633 	}
634 	channel->desired_mode = mode;
635 	musb_writew(epio, MUSB_TXCSR, csr);
636 #else
637 	if (!is_cppi_enabled() && !tusb_dma_omap())
638 		return false;
639 
640 	channel->actual_len = 0;
641 
642 	/*
643 	 * TX uses "RNDIS" mode automatically but needs help
644 	 * to identify the zero-length-final-packet case.
645 	 */
646 	mode = (urb->transfer_flags & URB_ZERO_PACKET) ? 1 : 0;
647 #endif
648 
649 	qh->segsize = length;
650 
651 	/*
652 	 * Ensure the data reaches to main memory before starting
653 	 * DMA transfer
654 	 */
655 	wmb();
656 
657 	if (!dma->channel_program(channel, pkt_size, mode,
658 			urb->transfer_dma + offset, length)) {
659 		dma->channel_release(channel);
660 		hw_ep->tx_channel = NULL;
661 
662 		csr = musb_readw(epio, MUSB_TXCSR);
663 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
664 		musb_writew(epio, MUSB_TXCSR, csr | MUSB_TXCSR_H_WZC_BITS);
665 		return false;
666 	}
667 	return true;
668 }
669 
670 /*
671  * Program an HDRC endpoint as per the given URB
672  * Context: irqs blocked, controller lock held
673  */
674 static void musb_ep_program(struct musb *musb, u8 epnum,
675 			struct urb *urb, int is_out,
676 			u8 *buf, u32 offset, u32 len)
677 {
678 	struct dma_controller	*dma_controller;
679 	struct dma_channel	*dma_channel;
680 	u8			dma_ok;
681 	void __iomem		*mbase = musb->mregs;
682 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
683 	void __iomem		*epio = hw_ep->regs;
684 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, !is_out);
685 	u16			packet_sz = qh->maxpacket;
686 
687 	dev_dbg(musb->controller, "%s hw%d urb %p spd%d dev%d ep%d%s "
688 				"h_addr%02x h_port%02x bytes %d\n",
689 			is_out ? "-->" : "<--",
690 			epnum, urb, urb->dev->speed,
691 			qh->addr_reg, qh->epnum, is_out ? "out" : "in",
692 			qh->h_addr_reg, qh->h_port_reg,
693 			len);
694 
695 	musb_ep_select(mbase, epnum);
696 
697 	/* candidate for DMA? */
698 	dma_controller = musb->dma_controller;
699 	if (is_dma_capable() && epnum && dma_controller) {
700 		dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel;
701 		if (!dma_channel) {
702 			dma_channel = dma_controller->channel_alloc(
703 					dma_controller, hw_ep, is_out);
704 			if (is_out)
705 				hw_ep->tx_channel = dma_channel;
706 			else
707 				hw_ep->rx_channel = dma_channel;
708 		}
709 	} else
710 		dma_channel = NULL;
711 
712 	/* make sure we clear DMAEnab, autoSet bits from previous run */
713 
714 	/* OUT/transmit/EP0 or IN/receive? */
715 	if (is_out) {
716 		u16	csr;
717 		u16	int_txe;
718 		u16	load_count;
719 
720 		csr = musb_readw(epio, MUSB_TXCSR);
721 
722 		/* disable interrupt in case we flush */
723 		int_txe = musb_readw(mbase, MUSB_INTRTXE);
724 		musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
725 
726 		/* general endpoint setup */
727 		if (epnum) {
728 			/* flush all old state, set default */
729 			musb_h_tx_flush_fifo(hw_ep);
730 
731 			/*
732 			 * We must not clear the DMAMODE bit before or in
733 			 * the same cycle with the DMAENAB bit, so we clear
734 			 * the latter first...
735 			 */
736 			csr &= ~(MUSB_TXCSR_H_NAKTIMEOUT
737 					| MUSB_TXCSR_AUTOSET
738 					| MUSB_TXCSR_DMAENAB
739 					| MUSB_TXCSR_FRCDATATOG
740 					| MUSB_TXCSR_H_RXSTALL
741 					| MUSB_TXCSR_H_ERROR
742 					| MUSB_TXCSR_TXPKTRDY
743 					);
744 			csr |= MUSB_TXCSR_MODE;
745 
746 			if (usb_gettoggle(urb->dev, qh->epnum, 1))
747 				csr |= MUSB_TXCSR_H_WR_DATATOGGLE
748 					| MUSB_TXCSR_H_DATATOGGLE;
749 			else
750 				csr |= MUSB_TXCSR_CLRDATATOG;
751 
752 			musb_writew(epio, MUSB_TXCSR, csr);
753 			/* REVISIT may need to clear FLUSHFIFO ... */
754 			csr &= ~MUSB_TXCSR_DMAMODE;
755 			musb_writew(epio, MUSB_TXCSR, csr);
756 			csr = musb_readw(epio, MUSB_TXCSR);
757 		} else {
758 			/* endpoint 0: just flush */
759 			musb_h_ep0_flush_fifo(hw_ep);
760 		}
761 
762 		/* target addr and (for multipoint) hub addr/port */
763 		if (musb->is_multipoint) {
764 			musb_write_txfunaddr(mbase, epnum, qh->addr_reg);
765 			musb_write_txhubaddr(mbase, epnum, qh->h_addr_reg);
766 			musb_write_txhubport(mbase, epnum, qh->h_port_reg);
767 /* FIXME if !epnum, do the same for RX ... */
768 		} else
769 			musb_writeb(mbase, MUSB_FADDR, qh->addr_reg);
770 
771 		/* protocol/endpoint/interval/NAKlimit */
772 		if (epnum) {
773 			musb_writeb(epio, MUSB_TXTYPE, qh->type_reg);
774 			if (musb->double_buffer_not_ok)
775 				musb_writew(epio, MUSB_TXMAXP,
776 						hw_ep->max_packet_sz_tx);
777 			else
778 				musb_writew(epio, MUSB_TXMAXP,
779 						qh->maxpacket |
780 						((qh->hb_mult - 1) << 11));
781 			musb_writeb(epio, MUSB_TXINTERVAL, qh->intv_reg);
782 		} else {
783 			musb_writeb(epio, MUSB_NAKLIMIT0, qh->intv_reg);
784 			if (musb->is_multipoint)
785 				musb_writeb(epio, MUSB_TYPE0,
786 						qh->type_reg);
787 		}
788 
789 		if (can_bulk_split(musb, qh->type))
790 			load_count = min((u32) hw_ep->max_packet_sz_tx,
791 						len);
792 		else
793 			load_count = min((u32) packet_sz, len);
794 
795 		if (dma_channel && musb_tx_dma_program(dma_controller,
796 					hw_ep, qh, urb, offset, len))
797 			load_count = 0;
798 
799 		if (load_count) {
800 			/* PIO to load FIFO */
801 			qh->segsize = load_count;
802 			musb_write_fifo(hw_ep, load_count, buf);
803 		}
804 
805 		/* re-enable interrupt */
806 		musb_writew(mbase, MUSB_INTRTXE, int_txe);
807 
808 	/* IN/receive */
809 	} else {
810 		u16	csr;
811 
812 		if (hw_ep->rx_reinit) {
813 			musb_rx_reinit(musb, qh, hw_ep);
814 
815 			/* init new state: toggle and NYET, maybe DMA later */
816 			if (usb_gettoggle(urb->dev, qh->epnum, 0))
817 				csr = MUSB_RXCSR_H_WR_DATATOGGLE
818 					| MUSB_RXCSR_H_DATATOGGLE;
819 			else
820 				csr = 0;
821 			if (qh->type == USB_ENDPOINT_XFER_INT)
822 				csr |= MUSB_RXCSR_DISNYET;
823 
824 		} else {
825 			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
826 
827 			if (csr & (MUSB_RXCSR_RXPKTRDY
828 					| MUSB_RXCSR_DMAENAB
829 					| MUSB_RXCSR_H_REQPKT))
830 				ERR("broken !rx_reinit, ep%d csr %04x\n",
831 						hw_ep->epnum, csr);
832 
833 			/* scrub any stale state, leaving toggle alone */
834 			csr &= MUSB_RXCSR_DISNYET;
835 		}
836 
837 		/* kick things off */
838 
839 		if ((is_cppi_enabled() || tusb_dma_omap()) && dma_channel) {
840 			/* Candidate for DMA */
841 			dma_channel->actual_len = 0L;
842 			qh->segsize = len;
843 
844 			/* AUTOREQ is in a DMA register */
845 			musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
846 			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
847 
848 			/*
849 			 * Unless caller treats short RX transfers as
850 			 * errors, we dare not queue multiple transfers.
851 			 */
852 			dma_ok = dma_controller->channel_program(dma_channel,
853 					packet_sz, !(urb->transfer_flags &
854 						     URB_SHORT_NOT_OK),
855 					urb->transfer_dma + offset,
856 					qh->segsize);
857 			if (!dma_ok) {
858 				dma_controller->channel_release(dma_channel);
859 				hw_ep->rx_channel = dma_channel = NULL;
860 			} else
861 				csr |= MUSB_RXCSR_DMAENAB;
862 		}
863 
864 		csr |= MUSB_RXCSR_H_REQPKT;
865 		dev_dbg(musb->controller, "RXCSR%d := %04x\n", epnum, csr);
866 		musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
867 		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
868 	}
869 }
870 
871 
872 /*
873  * Service the default endpoint (ep0) as host.
874  * Return true until it's time to start the status stage.
875  */
876 static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
877 {
878 	bool			 more = false;
879 	u8			*fifo_dest = NULL;
880 	u16			fifo_count = 0;
881 	struct musb_hw_ep	*hw_ep = musb->control_ep;
882 	struct musb_qh		*qh = hw_ep->in_qh;
883 	struct usb_ctrlrequest	*request;
884 
885 	switch (musb->ep0_stage) {
886 	case MUSB_EP0_IN:
887 		fifo_dest = urb->transfer_buffer + urb->actual_length;
888 		fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
889 				   urb->actual_length);
890 		if (fifo_count < len)
891 			urb->status = -EOVERFLOW;
892 
893 		musb_read_fifo(hw_ep, fifo_count, fifo_dest);
894 
895 		urb->actual_length += fifo_count;
896 		if (len < qh->maxpacket) {
897 			/* always terminate on short read; it's
898 			 * rarely reported as an error.
899 			 */
900 		} else if (urb->actual_length <
901 				urb->transfer_buffer_length)
902 			more = true;
903 		break;
904 	case MUSB_EP0_START:
905 		request = (struct usb_ctrlrequest *) urb->setup_packet;
906 
907 		if (!request->wLength) {
908 			dev_dbg(musb->controller, "start no-DATA\n");
909 			break;
910 		} else if (request->bRequestType & USB_DIR_IN) {
911 			dev_dbg(musb->controller, "start IN-DATA\n");
912 			musb->ep0_stage = MUSB_EP0_IN;
913 			more = true;
914 			break;
915 		} else {
916 			dev_dbg(musb->controller, "start OUT-DATA\n");
917 			musb->ep0_stage = MUSB_EP0_OUT;
918 			more = true;
919 		}
920 		/* FALLTHROUGH */
921 	case MUSB_EP0_OUT:
922 		fifo_count = min_t(size_t, qh->maxpacket,
923 				   urb->transfer_buffer_length -
924 				   urb->actual_length);
925 		if (fifo_count) {
926 			fifo_dest = (u8 *) (urb->transfer_buffer
927 					+ urb->actual_length);
928 			dev_dbg(musb->controller, "Sending %d byte%s to ep0 fifo %p\n",
929 					fifo_count,
930 					(fifo_count == 1) ? "" : "s",
931 					fifo_dest);
932 			musb_write_fifo(hw_ep, fifo_count, fifo_dest);
933 
934 			urb->actual_length += fifo_count;
935 			more = true;
936 		}
937 		break;
938 	default:
939 		ERR("bogus ep0 stage %d\n", musb->ep0_stage);
940 		break;
941 	}
942 
943 	return more;
944 }
945 
946 /*
947  * Handle default endpoint interrupt as host. Only called in IRQ time
948  * from musb_interrupt().
949  *
950  * called with controller irqlocked
951  */
952 irqreturn_t musb_h_ep0_irq(struct musb *musb)
953 {
954 	struct urb		*urb;
955 	u16			csr, len;
956 	int			status = 0;
957 	void __iomem		*mbase = musb->mregs;
958 	struct musb_hw_ep	*hw_ep = musb->control_ep;
959 	void __iomem		*epio = hw_ep->regs;
960 	struct musb_qh		*qh = hw_ep->in_qh;
961 	bool			complete = false;
962 	irqreturn_t		retval = IRQ_NONE;
963 
964 	/* ep0 only has one queue, "in" */
965 	urb = next_urb(qh);
966 
967 	musb_ep_select(mbase, 0);
968 	csr = musb_readw(epio, MUSB_CSR0);
969 	len = (csr & MUSB_CSR0_RXPKTRDY)
970 			? musb_readb(epio, MUSB_COUNT0)
971 			: 0;
972 
973 	dev_dbg(musb->controller, "<== csr0 %04x, qh %p, count %d, urb %p, stage %d\n",
974 		csr, qh, len, urb, musb->ep0_stage);
975 
976 	/* if we just did status stage, we are done */
977 	if (MUSB_EP0_STATUS == musb->ep0_stage) {
978 		retval = IRQ_HANDLED;
979 		complete = true;
980 	}
981 
982 	/* prepare status */
983 	if (csr & MUSB_CSR0_H_RXSTALL) {
984 		dev_dbg(musb->controller, "STALLING ENDPOINT\n");
985 		status = -EPIPE;
986 
987 	} else if (csr & MUSB_CSR0_H_ERROR) {
988 		dev_dbg(musb->controller, "no response, csr0 %04x\n", csr);
989 		status = -EPROTO;
990 
991 	} else if (csr & MUSB_CSR0_H_NAKTIMEOUT) {
992 		dev_dbg(musb->controller, "control NAK timeout\n");
993 
994 		/* NOTE:  this code path would be a good place to PAUSE a
995 		 * control transfer, if another one is queued, so that
996 		 * ep0 is more likely to stay busy.  That's already done
997 		 * for bulk RX transfers.
998 		 *
999 		 * if (qh->ring.next != &musb->control), then
1000 		 * we have a candidate... NAKing is *NOT* an error
1001 		 */
1002 		musb_writew(epio, MUSB_CSR0, 0);
1003 		retval = IRQ_HANDLED;
1004 	}
1005 
1006 	if (status) {
1007 		dev_dbg(musb->controller, "aborting\n");
1008 		retval = IRQ_HANDLED;
1009 		if (urb)
1010 			urb->status = status;
1011 		complete = true;
1012 
1013 		/* use the proper sequence to abort the transfer */
1014 		if (csr & MUSB_CSR0_H_REQPKT) {
1015 			csr &= ~MUSB_CSR0_H_REQPKT;
1016 			musb_writew(epio, MUSB_CSR0, csr);
1017 			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1018 			musb_writew(epio, MUSB_CSR0, csr);
1019 		} else {
1020 			musb_h_ep0_flush_fifo(hw_ep);
1021 		}
1022 
1023 		musb_writeb(epio, MUSB_NAKLIMIT0, 0);
1024 
1025 		/* clear it */
1026 		musb_writew(epio, MUSB_CSR0, 0);
1027 	}
1028 
1029 	if (unlikely(!urb)) {
1030 		/* stop endpoint since we have no place for its data, this
1031 		 * SHOULD NEVER HAPPEN! */
1032 		ERR("no URB for end 0\n");
1033 
1034 		musb_h_ep0_flush_fifo(hw_ep);
1035 		goto done;
1036 	}
1037 
1038 	if (!complete) {
1039 		/* call common logic and prepare response */
1040 		if (musb_h_ep0_continue(musb, len, urb)) {
1041 			/* more packets required */
1042 			csr = (MUSB_EP0_IN == musb->ep0_stage)
1043 				?  MUSB_CSR0_H_REQPKT : MUSB_CSR0_TXPKTRDY;
1044 		} else {
1045 			/* data transfer complete; perform status phase */
1046 			if (usb_pipeout(urb->pipe)
1047 					|| !urb->transfer_buffer_length)
1048 				csr = MUSB_CSR0_H_STATUSPKT
1049 					| MUSB_CSR0_H_REQPKT;
1050 			else
1051 				csr = MUSB_CSR0_H_STATUSPKT
1052 					| MUSB_CSR0_TXPKTRDY;
1053 
1054 			/* flag status stage */
1055 			musb->ep0_stage = MUSB_EP0_STATUS;
1056 
1057 			dev_dbg(musb->controller, "ep0 STATUS, csr %04x\n", csr);
1058 
1059 		}
1060 		musb_writew(epio, MUSB_CSR0, csr);
1061 		retval = IRQ_HANDLED;
1062 	} else
1063 		musb->ep0_stage = MUSB_EP0_IDLE;
1064 
1065 	/* call completion handler if done */
1066 	if (complete)
1067 		musb_advance_schedule(musb, urb, hw_ep, 1);
1068 done:
1069 	return retval;
1070 }
1071 
1072 
1073 #ifdef CONFIG_USB_INVENTRA_DMA
1074 
1075 /* Host side TX (OUT) using Mentor DMA works as follows:
1076 	submit_urb ->
1077 		- if queue was empty, Program Endpoint
1078 		- ... which starts DMA to fifo in mode 1 or 0
1079 
1080 	DMA Isr (transfer complete) -> TxAvail()
1081 		- Stop DMA (~DmaEnab)	(<--- Alert ... currently happens
1082 					only in musb_cleanup_urb)
1083 		- TxPktRdy has to be set in mode 0 or for
1084 			short packets in mode 1.
1085 */
1086 
1087 #endif
1088 
1089 /* Service a Tx-Available or dma completion irq for the endpoint */
1090 void musb_host_tx(struct musb *musb, u8 epnum)
1091 {
1092 	int			pipe;
1093 	bool			done = false;
1094 	u16			tx_csr;
1095 	size_t			length = 0;
1096 	size_t			offset = 0;
1097 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1098 	void __iomem		*epio = hw_ep->regs;
1099 	struct musb_qh		*qh = hw_ep->out_qh;
1100 	struct urb		*urb = next_urb(qh);
1101 	u32			status = 0;
1102 	void __iomem		*mbase = musb->mregs;
1103 	struct dma_channel	*dma;
1104 	bool			transfer_pending = false;
1105 
1106 	musb_ep_select(mbase, epnum);
1107 	tx_csr = musb_readw(epio, MUSB_TXCSR);
1108 
1109 	/* with CPPI, DMA sometimes triggers "extra" irqs */
1110 	if (!urb) {
1111 		dev_dbg(musb->controller, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1112 		return;
1113 	}
1114 
1115 	pipe = urb->pipe;
1116 	dma = is_dma_capable() ? hw_ep->tx_channel : NULL;
1117 	dev_dbg(musb->controller, "OUT/TX%d end, csr %04x%s\n", epnum, tx_csr,
1118 			dma ? ", dma" : "");
1119 
1120 	/* check for errors */
1121 	if (tx_csr & MUSB_TXCSR_H_RXSTALL) {
1122 		/* dma was disabled, fifo flushed */
1123 		dev_dbg(musb->controller, "TX end %d stall\n", epnum);
1124 
1125 		/* stall; record URB status */
1126 		status = -EPIPE;
1127 
1128 	} else if (tx_csr & MUSB_TXCSR_H_ERROR) {
1129 		/* (NON-ISO) dma was disabled, fifo flushed */
1130 		dev_dbg(musb->controller, "TX 3strikes on ep=%d\n", epnum);
1131 
1132 		status = -ETIMEDOUT;
1133 
1134 	} else if (tx_csr & MUSB_TXCSR_H_NAKTIMEOUT) {
1135 		dev_dbg(musb->controller, "TX end=%d device not responding\n", epnum);
1136 
1137 		/* NOTE:  this code path would be a good place to PAUSE a
1138 		 * transfer, if there's some other (nonperiodic) tx urb
1139 		 * that could use this fifo.  (dma complicates it...)
1140 		 * That's already done for bulk RX transfers.
1141 		 *
1142 		 * if (bulk && qh->ring.next != &musb->out_bulk), then
1143 		 * we have a candidate... NAKing is *NOT* an error
1144 		 */
1145 		musb_ep_select(mbase, epnum);
1146 		musb_writew(epio, MUSB_TXCSR,
1147 				MUSB_TXCSR_H_WZC_BITS
1148 				| MUSB_TXCSR_TXPKTRDY);
1149 		return;
1150 	}
1151 
1152 	if (status) {
1153 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1154 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1155 			(void) musb->dma_controller->channel_abort(dma);
1156 		}
1157 
1158 		/* do the proper sequence to abort the transfer in the
1159 		 * usb core; the dma engine should already be stopped.
1160 		 */
1161 		musb_h_tx_flush_fifo(hw_ep);
1162 		tx_csr &= ~(MUSB_TXCSR_AUTOSET
1163 				| MUSB_TXCSR_DMAENAB
1164 				| MUSB_TXCSR_H_ERROR
1165 				| MUSB_TXCSR_H_RXSTALL
1166 				| MUSB_TXCSR_H_NAKTIMEOUT
1167 				);
1168 
1169 		musb_ep_select(mbase, epnum);
1170 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1171 		/* REVISIT may need to clear FLUSHFIFO ... */
1172 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1173 		musb_writeb(epio, MUSB_TXINTERVAL, 0);
1174 
1175 		done = true;
1176 	}
1177 
1178 	/* second cppi case */
1179 	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1180 		dev_dbg(musb->controller, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1181 		return;
1182 	}
1183 
1184 	if (is_dma_capable() && dma && !status) {
1185 		/*
1186 		 * DMA has completed.  But if we're using DMA mode 1 (multi
1187 		 * packet DMA), we need a terminal TXPKTRDY interrupt before
1188 		 * we can consider this transfer completed, lest we trash
1189 		 * its last packet when writing the next URB's data.  So we
1190 		 * switch back to mode 0 to get that interrupt; we'll come
1191 		 * back here once it happens.
1192 		 */
1193 		if (tx_csr & MUSB_TXCSR_DMAMODE) {
1194 			/*
1195 			 * We shouldn't clear DMAMODE with DMAENAB set; so
1196 			 * clear them in a safe order.  That should be OK
1197 			 * once TXPKTRDY has been set (and I've never seen
1198 			 * it being 0 at this moment -- DMA interrupt latency
1199 			 * is significant) but if it hasn't been then we have
1200 			 * no choice but to stop being polite and ignore the
1201 			 * programmer's guide... :-)
1202 			 *
1203 			 * Note that we must write TXCSR with TXPKTRDY cleared
1204 			 * in order not to re-trigger the packet send (this bit
1205 			 * can't be cleared by CPU), and there's another caveat:
1206 			 * TXPKTRDY may be set shortly and then cleared in the
1207 			 * double-buffered FIFO mode, so we do an extra TXCSR
1208 			 * read for debouncing...
1209 			 */
1210 			tx_csr &= musb_readw(epio, MUSB_TXCSR);
1211 			if (tx_csr & MUSB_TXCSR_TXPKTRDY) {
1212 				tx_csr &= ~(MUSB_TXCSR_DMAENAB |
1213 					    MUSB_TXCSR_TXPKTRDY);
1214 				musb_writew(epio, MUSB_TXCSR,
1215 					    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1216 			}
1217 			tx_csr &= ~(MUSB_TXCSR_DMAMODE |
1218 				    MUSB_TXCSR_TXPKTRDY);
1219 			musb_writew(epio, MUSB_TXCSR,
1220 				    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1221 
1222 			/*
1223 			 * There is no guarantee that we'll get an interrupt
1224 			 * after clearing DMAMODE as we might have done this
1225 			 * too late (after TXPKTRDY was cleared by controller).
1226 			 * Re-read TXCSR as we have spoiled its previous value.
1227 			 */
1228 			tx_csr = musb_readw(epio, MUSB_TXCSR);
1229 		}
1230 
1231 		/*
1232 		 * We may get here from a DMA completion or TXPKTRDY interrupt.
1233 		 * In any case, we must check the FIFO status here and bail out
1234 		 * only if the FIFO still has data -- that should prevent the
1235 		 * "missed" TXPKTRDY interrupts and deal with double-buffered
1236 		 * FIFO mode too...
1237 		 */
1238 		if (tx_csr & (MUSB_TXCSR_FIFONOTEMPTY | MUSB_TXCSR_TXPKTRDY)) {
1239 			dev_dbg(musb->controller, "DMA complete but packet still in FIFO, "
1240 			    "CSR %04x\n", tx_csr);
1241 			return;
1242 		}
1243 	}
1244 
1245 	if (!status || dma || usb_pipeisoc(pipe)) {
1246 		if (dma)
1247 			length = dma->actual_len;
1248 		else
1249 			length = qh->segsize;
1250 		qh->offset += length;
1251 
1252 		if (usb_pipeisoc(pipe)) {
1253 			struct usb_iso_packet_descriptor	*d;
1254 
1255 			d = urb->iso_frame_desc + qh->iso_idx;
1256 			d->actual_length = length;
1257 			d->status = status;
1258 			if (++qh->iso_idx >= urb->number_of_packets) {
1259 				done = true;
1260 			} else {
1261 				d++;
1262 				offset = d->offset;
1263 				length = d->length;
1264 			}
1265 		} else if (dma && urb->transfer_buffer_length == qh->offset) {
1266 			done = true;
1267 		} else {
1268 			/* see if we need to send more data, or ZLP */
1269 			if (qh->segsize < qh->maxpacket)
1270 				done = true;
1271 			else if (qh->offset == urb->transfer_buffer_length
1272 					&& !(urb->transfer_flags
1273 						& URB_ZERO_PACKET))
1274 				done = true;
1275 			if (!done) {
1276 				offset = qh->offset;
1277 				length = urb->transfer_buffer_length - offset;
1278 				transfer_pending = true;
1279 			}
1280 		}
1281 	}
1282 
1283 	/* urb->status != -EINPROGRESS means request has been faulted,
1284 	 * so we must abort this transfer after cleanup
1285 	 */
1286 	if (urb->status != -EINPROGRESS) {
1287 		done = true;
1288 		if (status == 0)
1289 			status = urb->status;
1290 	}
1291 
1292 	if (done) {
1293 		/* set status */
1294 		urb->status = status;
1295 		urb->actual_length = qh->offset;
1296 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_OUT);
1297 		return;
1298 	} else if ((usb_pipeisoc(pipe) || transfer_pending) && dma) {
1299 		if (musb_tx_dma_program(musb->dma_controller, hw_ep, qh, urb,
1300 				offset, length)) {
1301 			if (is_cppi_enabled() || tusb_dma_omap())
1302 				musb_h_tx_dma_start(hw_ep);
1303 			return;
1304 		}
1305 	} else	if (tx_csr & MUSB_TXCSR_DMAENAB) {
1306 		dev_dbg(musb->controller, "not complete, but DMA enabled?\n");
1307 		return;
1308 	}
1309 
1310 	/*
1311 	 * PIO: start next packet in this URB.
1312 	 *
1313 	 * REVISIT: some docs say that when hw_ep->tx_double_buffered,
1314 	 * (and presumably, FIFO is not half-full) we should write *two*
1315 	 * packets before updating TXCSR; other docs disagree...
1316 	 */
1317 	if (length > qh->maxpacket)
1318 		length = qh->maxpacket;
1319 	/* Unmap the buffer so that CPU can use it */
1320 	usb_hcd_unmap_urb_for_dma(musb_to_hcd(musb), urb);
1321 	musb_write_fifo(hw_ep, length, urb->transfer_buffer + offset);
1322 	qh->segsize = length;
1323 
1324 	musb_ep_select(mbase, epnum);
1325 	musb_writew(epio, MUSB_TXCSR,
1326 			MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
1327 }
1328 
1329 
1330 #ifdef CONFIG_USB_INVENTRA_DMA
1331 
1332 /* Host side RX (IN) using Mentor DMA works as follows:
1333 	submit_urb ->
1334 		- if queue was empty, ProgramEndpoint
1335 		- first IN token is sent out (by setting ReqPkt)
1336 	LinuxIsr -> RxReady()
1337 	/\	=> first packet is received
1338 	|	- Set in mode 0 (DmaEnab, ~ReqPkt)
1339 	|		-> DMA Isr (transfer complete) -> RxReady()
1340 	|		    - Ack receive (~RxPktRdy), turn off DMA (~DmaEnab)
1341 	|		    - if urb not complete, send next IN token (ReqPkt)
1342 	|			   |		else complete urb.
1343 	|			   |
1344 	---------------------------
1345  *
1346  * Nuances of mode 1:
1347  *	For short packets, no ack (+RxPktRdy) is sent automatically
1348  *	(even if AutoClear is ON)
1349  *	For full packets, ack (~RxPktRdy) and next IN token (+ReqPkt) is sent
1350  *	automatically => major problem, as collecting the next packet becomes
1351  *	difficult. Hence mode 1 is not used.
1352  *
1353  * REVISIT
1354  *	All we care about at this driver level is that
1355  *       (a) all URBs terminate with REQPKT cleared and fifo(s) empty;
1356  *       (b) termination conditions are: short RX, or buffer full;
1357  *       (c) fault modes include
1358  *           - iff URB_SHORT_NOT_OK, short RX status is -EREMOTEIO.
1359  *             (and that endpoint's dma queue stops immediately)
1360  *           - overflow (full, PLUS more bytes in the terminal packet)
1361  *
1362  *	So for example, usb-storage sets URB_SHORT_NOT_OK, and would
1363  *	thus be a great candidate for using mode 1 ... for all but the
1364  *	last packet of one URB's transfer.
1365  */
1366 
1367 #endif
1368 
1369 /* Schedule next QH from musb->in_bulk and move the current qh to
1370  * the end; avoids starvation for other endpoints.
1371  */
1372 static void musb_bulk_rx_nak_timeout(struct musb *musb, struct musb_hw_ep *ep)
1373 {
1374 	struct dma_channel	*dma;
1375 	struct urb		*urb;
1376 	void __iomem		*mbase = musb->mregs;
1377 	void __iomem		*epio = ep->regs;
1378 	struct musb_qh		*cur_qh, *next_qh;
1379 	u16			rx_csr;
1380 
1381 	musb_ep_select(mbase, ep->epnum);
1382 	dma = is_dma_capable() ? ep->rx_channel : NULL;
1383 
1384 	/* clear nak timeout bit */
1385 	rx_csr = musb_readw(epio, MUSB_RXCSR);
1386 	rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1387 	rx_csr &= ~MUSB_RXCSR_DATAERROR;
1388 	musb_writew(epio, MUSB_RXCSR, rx_csr);
1389 
1390 	cur_qh = first_qh(&musb->in_bulk);
1391 	if (cur_qh) {
1392 		urb = next_urb(cur_qh);
1393 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1394 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1395 			musb->dma_controller->channel_abort(dma);
1396 			urb->actual_length += dma->actual_len;
1397 			dma->actual_len = 0L;
1398 		}
1399 		musb_save_toggle(cur_qh, 1, urb);
1400 
1401 		/* move cur_qh to end of queue */
1402 		list_move_tail(&cur_qh->ring, &musb->in_bulk);
1403 
1404 		/* get the next qh from musb->in_bulk */
1405 		next_qh = first_qh(&musb->in_bulk);
1406 
1407 		/* set rx_reinit and schedule the next qh */
1408 		ep->rx_reinit = 1;
1409 		musb_start_urb(musb, 1, next_qh);
1410 	}
1411 }
1412 
1413 /*
1414  * Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
1415  * and high-bandwidth IN transfer cases.
1416  */
1417 void musb_host_rx(struct musb *musb, u8 epnum)
1418 {
1419 	struct urb		*urb;
1420 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1421 	void __iomem		*epio = hw_ep->regs;
1422 	struct musb_qh		*qh = hw_ep->in_qh;
1423 	size_t			xfer_len;
1424 	void __iomem		*mbase = musb->mregs;
1425 	int			pipe;
1426 	u16			rx_csr, val;
1427 	bool			iso_err = false;
1428 	bool			done = false;
1429 	u32			status;
1430 	struct dma_channel	*dma;
1431 
1432 	musb_ep_select(mbase, epnum);
1433 
1434 	urb = next_urb(qh);
1435 	dma = is_dma_capable() ? hw_ep->rx_channel : NULL;
1436 	status = 0;
1437 	xfer_len = 0;
1438 
1439 	rx_csr = musb_readw(epio, MUSB_RXCSR);
1440 	val = rx_csr;
1441 
1442 	if (unlikely(!urb)) {
1443 		/* REVISIT -- THIS SHOULD NEVER HAPPEN ... but, at least
1444 		 * usbtest #11 (unlinks) triggers it regularly, sometimes
1445 		 * with fifo full.  (Only with DMA??)
1446 		 */
1447 		dev_dbg(musb->controller, "BOGUS RX%d ready, csr %04x, count %d\n", epnum, val,
1448 			musb_readw(epio, MUSB_RXCOUNT));
1449 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1450 		return;
1451 	}
1452 
1453 	pipe = urb->pipe;
1454 
1455 	dev_dbg(musb->controller, "<== hw %d rxcsr %04x, urb actual %d (+dma %zu)\n",
1456 		epnum, rx_csr, urb->actual_length,
1457 		dma ? dma->actual_len : 0);
1458 
1459 	/* check for errors, concurrent stall & unlink is not really
1460 	 * handled yet! */
1461 	if (rx_csr & MUSB_RXCSR_H_RXSTALL) {
1462 		dev_dbg(musb->controller, "RX end %d STALL\n", epnum);
1463 
1464 		/* stall; record URB status */
1465 		status = -EPIPE;
1466 
1467 	} else if (rx_csr & MUSB_RXCSR_H_ERROR) {
1468 		dev_dbg(musb->controller, "end %d RX proto error\n", epnum);
1469 
1470 		status = -EPROTO;
1471 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1472 
1473 	} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
1474 
1475 		if (USB_ENDPOINT_XFER_ISOC != qh->type) {
1476 			dev_dbg(musb->controller, "RX end %d NAK timeout\n", epnum);
1477 
1478 			/* NOTE: NAKing is *NOT* an error, so we want to
1479 			 * continue.  Except ... if there's a request for
1480 			 * another QH, use that instead of starving it.
1481 			 *
1482 			 * Devices like Ethernet and serial adapters keep
1483 			 * reads posted at all times, which will starve
1484 			 * other devices without this logic.
1485 			 */
1486 			if (usb_pipebulk(urb->pipe)
1487 					&& qh->mux == 1
1488 					&& !list_is_singular(&musb->in_bulk)) {
1489 				musb_bulk_rx_nak_timeout(musb, hw_ep);
1490 				return;
1491 			}
1492 			musb_ep_select(mbase, epnum);
1493 			rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1494 			rx_csr &= ~MUSB_RXCSR_DATAERROR;
1495 			musb_writew(epio, MUSB_RXCSR, rx_csr);
1496 
1497 			goto finish;
1498 		} else {
1499 			dev_dbg(musb->controller, "RX end %d ISO data error\n", epnum);
1500 			/* packet error reported later */
1501 			iso_err = true;
1502 		}
1503 	} else if (rx_csr & MUSB_RXCSR_INCOMPRX) {
1504 		dev_dbg(musb->controller, "end %d high bandwidth incomplete ISO packet RX\n",
1505 				epnum);
1506 		status = -EPROTO;
1507 	}
1508 
1509 	/* faults abort the transfer */
1510 	if (status) {
1511 		/* clean up dma and collect transfer count */
1512 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1513 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1514 			(void) musb->dma_controller->channel_abort(dma);
1515 			xfer_len = dma->actual_len;
1516 		}
1517 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1518 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1519 		done = true;
1520 		goto finish;
1521 	}
1522 
1523 	if (unlikely(dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY)) {
1524 		/* SHOULD NEVER HAPPEN ... but at least DaVinci has done it */
1525 		ERR("RX%d dma busy, csr %04x\n", epnum, rx_csr);
1526 		goto finish;
1527 	}
1528 
1529 	/* thorough shutdown for now ... given more precise fault handling
1530 	 * and better queueing support, we might keep a DMA pipeline going
1531 	 * while processing this irq for earlier completions.
1532 	 */
1533 
1534 	/* FIXME this is _way_ too much in-line logic for Mentor DMA */
1535 
1536 #ifndef CONFIG_USB_INVENTRA_DMA
1537 	if (rx_csr & MUSB_RXCSR_H_REQPKT)  {
1538 		/* REVISIT this happened for a while on some short reads...
1539 		 * the cleanup still needs investigation... looks bad...
1540 		 * and also duplicates dma cleanup code above ... plus,
1541 		 * shouldn't this be the "half full" double buffer case?
1542 		 */
1543 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1544 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1545 			(void) musb->dma_controller->channel_abort(dma);
1546 			xfer_len = dma->actual_len;
1547 			done = true;
1548 		}
1549 
1550 		dev_dbg(musb->controller, "RXCSR%d %04x, reqpkt, len %zu%s\n", epnum, rx_csr,
1551 				xfer_len, dma ? ", dma" : "");
1552 		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
1553 
1554 		musb_ep_select(mbase, epnum);
1555 		musb_writew(epio, MUSB_RXCSR,
1556 				MUSB_RXCSR_H_WZC_BITS | rx_csr);
1557 	}
1558 #endif
1559 	if (dma && (rx_csr & MUSB_RXCSR_DMAENAB)) {
1560 		xfer_len = dma->actual_len;
1561 
1562 		val &= ~(MUSB_RXCSR_DMAENAB
1563 			| MUSB_RXCSR_H_AUTOREQ
1564 			| MUSB_RXCSR_AUTOCLEAR
1565 			| MUSB_RXCSR_RXPKTRDY);
1566 		musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1567 
1568 #ifdef CONFIG_USB_INVENTRA_DMA
1569 		if (usb_pipeisoc(pipe)) {
1570 			struct usb_iso_packet_descriptor *d;
1571 
1572 			d = urb->iso_frame_desc + qh->iso_idx;
1573 			d->actual_length = xfer_len;
1574 
1575 			/* even if there was an error, we did the dma
1576 			 * for iso_frame_desc->length
1577 			 */
1578 			if (d->status != -EILSEQ && d->status != -EOVERFLOW)
1579 				d->status = 0;
1580 
1581 			if (++qh->iso_idx >= urb->number_of_packets)
1582 				done = true;
1583 			else
1584 				done = false;
1585 
1586 		} else  {
1587 		/* done if urb buffer is full or short packet is recd */
1588 		done = (urb->actual_length + xfer_len >=
1589 				urb->transfer_buffer_length
1590 			|| dma->actual_len < qh->maxpacket);
1591 		}
1592 
1593 		/* send IN token for next packet, without AUTOREQ */
1594 		if (!done) {
1595 			val |= MUSB_RXCSR_H_REQPKT;
1596 			musb_writew(epio, MUSB_RXCSR,
1597 				MUSB_RXCSR_H_WZC_BITS | val);
1598 		}
1599 
1600 		dev_dbg(musb->controller, "ep %d dma %s, rxcsr %04x, rxcount %d\n", epnum,
1601 			done ? "off" : "reset",
1602 			musb_readw(epio, MUSB_RXCSR),
1603 			musb_readw(epio, MUSB_RXCOUNT));
1604 #else
1605 		done = true;
1606 #endif
1607 	} else if (urb->status == -EINPROGRESS) {
1608 		/* if no errors, be sure a packet is ready for unloading */
1609 		if (unlikely(!(rx_csr & MUSB_RXCSR_RXPKTRDY))) {
1610 			status = -EPROTO;
1611 			ERR("Rx interrupt with no errors or packet!\n");
1612 
1613 			/* FIXME this is another "SHOULD NEVER HAPPEN" */
1614 
1615 /* SCRUB (RX) */
1616 			/* do the proper sequence to abort the transfer */
1617 			musb_ep_select(mbase, epnum);
1618 			val &= ~MUSB_RXCSR_H_REQPKT;
1619 			musb_writew(epio, MUSB_RXCSR, val);
1620 			goto finish;
1621 		}
1622 
1623 		/* we are expecting IN packets */
1624 #ifdef CONFIG_USB_INVENTRA_DMA
1625 		if (dma) {
1626 			struct dma_controller	*c;
1627 			u16			rx_count;
1628 			int			ret, length;
1629 			dma_addr_t		buf;
1630 
1631 			rx_count = musb_readw(epio, MUSB_RXCOUNT);
1632 
1633 			dev_dbg(musb->controller, "RX%d count %d, buffer 0x%x len %d/%d\n",
1634 					epnum, rx_count,
1635 					urb->transfer_dma
1636 						+ urb->actual_length,
1637 					qh->offset,
1638 					urb->transfer_buffer_length);
1639 
1640 			c = musb->dma_controller;
1641 
1642 			if (usb_pipeisoc(pipe)) {
1643 				int d_status = 0;
1644 				struct usb_iso_packet_descriptor *d;
1645 
1646 				d = urb->iso_frame_desc + qh->iso_idx;
1647 
1648 				if (iso_err) {
1649 					d_status = -EILSEQ;
1650 					urb->error_count++;
1651 				}
1652 				if (rx_count > d->length) {
1653 					if (d_status == 0) {
1654 						d_status = -EOVERFLOW;
1655 						urb->error_count++;
1656 					}
1657 					dev_dbg(musb->controller, "** OVERFLOW %d into %d\n",\
1658 					    rx_count, d->length);
1659 
1660 					length = d->length;
1661 				} else
1662 					length = rx_count;
1663 				d->status = d_status;
1664 				buf = urb->transfer_dma + d->offset;
1665 			} else {
1666 				length = rx_count;
1667 				buf = urb->transfer_dma +
1668 						urb->actual_length;
1669 			}
1670 
1671 			dma->desired_mode = 0;
1672 #ifdef USE_MODE1
1673 			/* because of the issue below, mode 1 will
1674 			 * only rarely behave with correct semantics.
1675 			 */
1676 			if ((urb->transfer_flags &
1677 						URB_SHORT_NOT_OK)
1678 				&& (urb->transfer_buffer_length -
1679 						urb->actual_length)
1680 					> qh->maxpacket)
1681 				dma->desired_mode = 1;
1682 			if (rx_count < hw_ep->max_packet_sz_rx) {
1683 				length = rx_count;
1684 				dma->desired_mode = 0;
1685 			} else {
1686 				length = urb->transfer_buffer_length;
1687 			}
1688 #endif
1689 
1690 /* Disadvantage of using mode 1:
1691  *	It's basically usable only for mass storage class; essentially all
1692  *	other protocols also terminate transfers on short packets.
1693  *
1694  * Details:
1695  *	An extra IN token is sent at the end of the transfer (due to AUTOREQ)
1696  *	If you try to use mode 1 for (transfer_buffer_length - 512), and try
1697  *	to use the extra IN token to grab the last packet using mode 0, then
1698  *	the problem is that you cannot be sure when the device will send the
1699  *	last packet and RxPktRdy set. Sometimes the packet is recd too soon
1700  *	such that it gets lost when RxCSR is re-set at the end of the mode 1
1701  *	transfer, while sometimes it is recd just a little late so that if you
1702  *	try to configure for mode 0 soon after the mode 1 transfer is
1703  *	completed, you will find rxcount 0. Okay, so you might think why not
1704  *	wait for an interrupt when the pkt is recd. Well, you won't get any!
1705  */
1706 
1707 			val = musb_readw(epio, MUSB_RXCSR);
1708 			val &= ~MUSB_RXCSR_H_REQPKT;
1709 
1710 			if (dma->desired_mode == 0)
1711 				val &= ~MUSB_RXCSR_H_AUTOREQ;
1712 			else
1713 				val |= MUSB_RXCSR_H_AUTOREQ;
1714 			val |= MUSB_RXCSR_DMAENAB;
1715 
1716 			/* autoclear shouldn't be set in high bandwidth */
1717 			if (qh->hb_mult == 1)
1718 				val |= MUSB_RXCSR_AUTOCLEAR;
1719 
1720 			musb_writew(epio, MUSB_RXCSR,
1721 				MUSB_RXCSR_H_WZC_BITS | val);
1722 
1723 			/* REVISIT if when actual_length != 0,
1724 			 * transfer_buffer_length needs to be
1725 			 * adjusted first...
1726 			 */
1727 			ret = c->channel_program(
1728 				dma, qh->maxpacket,
1729 				dma->desired_mode, buf, length);
1730 
1731 			if (!ret) {
1732 				c->channel_release(dma);
1733 				hw_ep->rx_channel = NULL;
1734 				dma = NULL;
1735 				/* REVISIT reset CSR */
1736 			}
1737 		}
1738 #endif	/* Mentor DMA */
1739 
1740 		if (!dma) {
1741 			/* Unmap the buffer so that CPU can use it */
1742 			usb_hcd_unmap_urb_for_dma(musb_to_hcd(musb), urb);
1743 			done = musb_host_packet_rx(musb, urb,
1744 					epnum, iso_err);
1745 			dev_dbg(musb->controller, "read %spacket\n", done ? "last " : "");
1746 		}
1747 	}
1748 
1749 finish:
1750 	urb->actual_length += xfer_len;
1751 	qh->offset += xfer_len;
1752 	if (done) {
1753 		if (urb->status == -EINPROGRESS)
1754 			urb->status = status;
1755 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_IN);
1756 	}
1757 }
1758 
1759 /* schedule nodes correspond to peripheral endpoints, like an OHCI QH.
1760  * the software schedule associates multiple such nodes with a given
1761  * host side hardware endpoint + direction; scheduling may activate
1762  * that hardware endpoint.
1763  */
1764 static int musb_schedule(
1765 	struct musb		*musb,
1766 	struct musb_qh		*qh,
1767 	int			is_in)
1768 {
1769 	int			idle;
1770 	int			best_diff;
1771 	int			best_end, epnum;
1772 	struct musb_hw_ep	*hw_ep = NULL;
1773 	struct list_head	*head = NULL;
1774 	u8			toggle;
1775 	u8			txtype;
1776 	struct urb		*urb = next_urb(qh);
1777 
1778 	/* use fixed hardware for control and bulk */
1779 	if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
1780 		head = &musb->control;
1781 		hw_ep = musb->control_ep;
1782 		goto success;
1783 	}
1784 
1785 	/* else, periodic transfers get muxed to other endpoints */
1786 
1787 	/*
1788 	 * We know this qh hasn't been scheduled, so all we need to do
1789 	 * is choose which hardware endpoint to put it on ...
1790 	 *
1791 	 * REVISIT what we really want here is a regular schedule tree
1792 	 * like e.g. OHCI uses.
1793 	 */
1794 	best_diff = 4096;
1795 	best_end = -1;
1796 
1797 	for (epnum = 1, hw_ep = musb->endpoints + 1;
1798 			epnum < musb->nr_endpoints;
1799 			epnum++, hw_ep++) {
1800 		int	diff;
1801 
1802 		if (musb_ep_get_qh(hw_ep, is_in) != NULL)
1803 			continue;
1804 
1805 		if (hw_ep == musb->bulk_ep)
1806 			continue;
1807 
1808 		if (is_in)
1809 			diff = hw_ep->max_packet_sz_rx;
1810 		else
1811 			diff = hw_ep->max_packet_sz_tx;
1812 		diff -= (qh->maxpacket * qh->hb_mult);
1813 
1814 		if (diff >= 0 && best_diff > diff) {
1815 
1816 			/*
1817 			 * Mentor controller has a bug in that if we schedule
1818 			 * a BULK Tx transfer on an endpoint that had earlier
1819 			 * handled ISOC then the BULK transfer has to start on
1820 			 * a zero toggle.  If the BULK transfer starts on a 1
1821 			 * toggle then this transfer will fail as the mentor
1822 			 * controller starts the Bulk transfer on a 0 toggle
1823 			 * irrespective of the programming of the toggle bits
1824 			 * in the TXCSR register.  Check for this condition
1825 			 * while allocating the EP for a Tx Bulk transfer.  If
1826 			 * so skip this EP.
1827 			 */
1828 			hw_ep = musb->endpoints + epnum;
1829 			toggle = usb_gettoggle(urb->dev, qh->epnum, !is_in);
1830 			txtype = (musb_readb(hw_ep->regs, MUSB_TXTYPE)
1831 					>> 4) & 0x3;
1832 			if (!is_in && (qh->type == USB_ENDPOINT_XFER_BULK) &&
1833 				toggle && (txtype == USB_ENDPOINT_XFER_ISOC))
1834 				continue;
1835 
1836 			best_diff = diff;
1837 			best_end = epnum;
1838 		}
1839 	}
1840 	/* use bulk reserved ep1 if no other ep is free */
1841 	if (best_end < 0 && qh->type == USB_ENDPOINT_XFER_BULK) {
1842 		hw_ep = musb->bulk_ep;
1843 		if (is_in)
1844 			head = &musb->in_bulk;
1845 		else
1846 			head = &musb->out_bulk;
1847 
1848 		/* Enable bulk RX NAK timeout scheme when bulk requests are
1849 		 * multiplexed.  This scheme doen't work in high speed to full
1850 		 * speed scenario as NAK interrupts are not coming from a
1851 		 * full speed device connected to a high speed device.
1852 		 * NAK timeout interval is 8 (128 uframe or 16ms) for HS and
1853 		 * 4 (8 frame or 8ms) for FS device.
1854 		 */
1855 		if (is_in && qh->dev)
1856 			qh->intv_reg =
1857 				(USB_SPEED_HIGH == qh->dev->speed) ? 8 : 4;
1858 		goto success;
1859 	} else if (best_end < 0) {
1860 		return -ENOSPC;
1861 	}
1862 
1863 	idle = 1;
1864 	qh->mux = 0;
1865 	hw_ep = musb->endpoints + best_end;
1866 	dev_dbg(musb->controller, "qh %p periodic slot %d\n", qh, best_end);
1867 success:
1868 	if (head) {
1869 		idle = list_empty(head);
1870 		list_add_tail(&qh->ring, head);
1871 		qh->mux = 1;
1872 	}
1873 	qh->hw_ep = hw_ep;
1874 	qh->hep->hcpriv = qh;
1875 	if (idle)
1876 		musb_start_urb(musb, is_in, qh);
1877 	return 0;
1878 }
1879 
1880 static int musb_urb_enqueue(
1881 	struct usb_hcd			*hcd,
1882 	struct urb			*urb,
1883 	gfp_t				mem_flags)
1884 {
1885 	unsigned long			flags;
1886 	struct musb			*musb = hcd_to_musb(hcd);
1887 	struct usb_host_endpoint	*hep = urb->ep;
1888 	struct musb_qh			*qh;
1889 	struct usb_endpoint_descriptor	*epd = &hep->desc;
1890 	int				ret;
1891 	unsigned			type_reg;
1892 	unsigned			interval;
1893 
1894 	/* host role must be active */
1895 	if (!is_host_active(musb) || !musb->is_active)
1896 		return -ENODEV;
1897 
1898 	spin_lock_irqsave(&musb->lock, flags);
1899 	ret = usb_hcd_link_urb_to_ep(hcd, urb);
1900 	qh = ret ? NULL : hep->hcpriv;
1901 	if (qh)
1902 		urb->hcpriv = qh;
1903 	spin_unlock_irqrestore(&musb->lock, flags);
1904 
1905 	/* DMA mapping was already done, if needed, and this urb is on
1906 	 * hep->urb_list now ... so we're done, unless hep wasn't yet
1907 	 * scheduled onto a live qh.
1908 	 *
1909 	 * REVISIT best to keep hep->hcpriv valid until the endpoint gets
1910 	 * disabled, testing for empty qh->ring and avoiding qh setup costs
1911 	 * except for the first urb queued after a config change.
1912 	 */
1913 	if (qh || ret)
1914 		return ret;
1915 
1916 	/* Allocate and initialize qh, minimizing the work done each time
1917 	 * hw_ep gets reprogrammed, or with irqs blocked.  Then schedule it.
1918 	 *
1919 	 * REVISIT consider a dedicated qh kmem_cache, so it's harder
1920 	 * for bugs in other kernel code to break this driver...
1921 	 */
1922 	qh = kzalloc(sizeof *qh, mem_flags);
1923 	if (!qh) {
1924 		spin_lock_irqsave(&musb->lock, flags);
1925 		usb_hcd_unlink_urb_from_ep(hcd, urb);
1926 		spin_unlock_irqrestore(&musb->lock, flags);
1927 		return -ENOMEM;
1928 	}
1929 
1930 	qh->hep = hep;
1931 	qh->dev = urb->dev;
1932 	INIT_LIST_HEAD(&qh->ring);
1933 	qh->is_ready = 1;
1934 
1935 	qh->maxpacket = usb_endpoint_maxp(epd);
1936 	qh->type = usb_endpoint_type(epd);
1937 
1938 	/* Bits 11 & 12 of wMaxPacketSize encode high bandwidth multiplier.
1939 	 * Some musb cores don't support high bandwidth ISO transfers; and
1940 	 * we don't (yet!) support high bandwidth interrupt transfers.
1941 	 */
1942 	qh->hb_mult = 1 + ((qh->maxpacket >> 11) & 0x03);
1943 	if (qh->hb_mult > 1) {
1944 		int ok = (qh->type == USB_ENDPOINT_XFER_ISOC);
1945 
1946 		if (ok)
1947 			ok = (usb_pipein(urb->pipe) && musb->hb_iso_rx)
1948 				|| (usb_pipeout(urb->pipe) && musb->hb_iso_tx);
1949 		if (!ok) {
1950 			ret = -EMSGSIZE;
1951 			goto done;
1952 		}
1953 		qh->maxpacket &= 0x7ff;
1954 	}
1955 
1956 	qh->epnum = usb_endpoint_num(epd);
1957 
1958 	/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
1959 	qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
1960 
1961 	/* precompute rxtype/txtype/type0 register */
1962 	type_reg = (qh->type << 4) | qh->epnum;
1963 	switch (urb->dev->speed) {
1964 	case USB_SPEED_LOW:
1965 		type_reg |= 0xc0;
1966 		break;
1967 	case USB_SPEED_FULL:
1968 		type_reg |= 0x80;
1969 		break;
1970 	default:
1971 		type_reg |= 0x40;
1972 	}
1973 	qh->type_reg = type_reg;
1974 
1975 	/* Precompute RXINTERVAL/TXINTERVAL register */
1976 	switch (qh->type) {
1977 	case USB_ENDPOINT_XFER_INT:
1978 		/*
1979 		 * Full/low speeds use the  linear encoding,
1980 		 * high speed uses the logarithmic encoding.
1981 		 */
1982 		if (urb->dev->speed <= USB_SPEED_FULL) {
1983 			interval = max_t(u8, epd->bInterval, 1);
1984 			break;
1985 		}
1986 		/* FALLTHROUGH */
1987 	case USB_ENDPOINT_XFER_ISOC:
1988 		/* ISO always uses logarithmic encoding */
1989 		interval = min_t(u8, epd->bInterval, 16);
1990 		break;
1991 	default:
1992 		/* REVISIT we actually want to use NAK limits, hinting to the
1993 		 * transfer scheduling logic to try some other qh, e.g. try
1994 		 * for 2 msec first:
1995 		 *
1996 		 * interval = (USB_SPEED_HIGH == urb->dev->speed) ? 16 : 2;
1997 		 *
1998 		 * The downside of disabling this is that transfer scheduling
1999 		 * gets VERY unfair for nonperiodic transfers; a misbehaving
2000 		 * peripheral could make that hurt.  That's perfectly normal
2001 		 * for reads from network or serial adapters ... so we have
2002 		 * partial NAKlimit support for bulk RX.
2003 		 *
2004 		 * The upside of disabling it is simpler transfer scheduling.
2005 		 */
2006 		interval = 0;
2007 	}
2008 	qh->intv_reg = interval;
2009 
2010 	/* precompute addressing for external hub/tt ports */
2011 	if (musb->is_multipoint) {
2012 		struct usb_device	*parent = urb->dev->parent;
2013 
2014 		if (parent != hcd->self.root_hub) {
2015 			qh->h_addr_reg = (u8) parent->devnum;
2016 
2017 			/* set up tt info if needed */
2018 			if (urb->dev->tt) {
2019 				qh->h_port_reg = (u8) urb->dev->ttport;
2020 				if (urb->dev->tt->hub)
2021 					qh->h_addr_reg =
2022 						(u8) urb->dev->tt->hub->devnum;
2023 				if (urb->dev->tt->multi)
2024 					qh->h_addr_reg |= 0x80;
2025 			}
2026 		}
2027 	}
2028 
2029 	/* invariant: hep->hcpriv is null OR the qh that's already scheduled.
2030 	 * until we get real dma queues (with an entry for each urb/buffer),
2031 	 * we only have work to do in the former case.
2032 	 */
2033 	spin_lock_irqsave(&musb->lock, flags);
2034 	if (hep->hcpriv) {
2035 		/* some concurrent activity submitted another urb to hep...
2036 		 * odd, rare, error prone, but legal.
2037 		 */
2038 		kfree(qh);
2039 		qh = NULL;
2040 		ret = 0;
2041 	} else
2042 		ret = musb_schedule(musb, qh,
2043 				epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK);
2044 
2045 	if (ret == 0) {
2046 		urb->hcpriv = qh;
2047 		/* FIXME set urb->start_frame for iso/intr, it's tested in
2048 		 * musb_start_urb(), but otherwise only konicawc cares ...
2049 		 */
2050 	}
2051 	spin_unlock_irqrestore(&musb->lock, flags);
2052 
2053 done:
2054 	if (ret != 0) {
2055 		spin_lock_irqsave(&musb->lock, flags);
2056 		usb_hcd_unlink_urb_from_ep(hcd, urb);
2057 		spin_unlock_irqrestore(&musb->lock, flags);
2058 		kfree(qh);
2059 	}
2060 	return ret;
2061 }
2062 
2063 
2064 /*
2065  * abort a transfer that's at the head of a hardware queue.
2066  * called with controller locked, irqs blocked
2067  * that hardware queue advances to the next transfer, unless prevented
2068  */
2069 static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh)
2070 {
2071 	struct musb_hw_ep	*ep = qh->hw_ep;
2072 	struct musb		*musb = ep->musb;
2073 	void __iomem		*epio = ep->regs;
2074 	unsigned		hw_end = ep->epnum;
2075 	void __iomem		*regs = ep->musb->mregs;
2076 	int			is_in = usb_pipein(urb->pipe);
2077 	int			status = 0;
2078 	u16			csr;
2079 
2080 	musb_ep_select(regs, hw_end);
2081 
2082 	if (is_dma_capable()) {
2083 		struct dma_channel	*dma;
2084 
2085 		dma = is_in ? ep->rx_channel : ep->tx_channel;
2086 		if (dma) {
2087 			status = ep->musb->dma_controller->channel_abort(dma);
2088 			dev_dbg(musb->controller,
2089 				"abort %cX%d DMA for urb %p --> %d\n",
2090 				is_in ? 'R' : 'T', ep->epnum,
2091 				urb, status);
2092 			urb->actual_length += dma->actual_len;
2093 		}
2094 	}
2095 
2096 	/* turn off DMA requests, discard state, stop polling ... */
2097 	if (is_in) {
2098 		/* giveback saves bulk toggle */
2099 		csr = musb_h_flush_rxfifo(ep, 0);
2100 
2101 		/* REVISIT we still get an irq; should likely clear the
2102 		 * endpoint's irq status here to avoid bogus irqs.
2103 		 * clearing that status is platform-specific...
2104 		 */
2105 	} else if (ep->epnum) {
2106 		musb_h_tx_flush_fifo(ep);
2107 		csr = musb_readw(epio, MUSB_TXCSR);
2108 		csr &= ~(MUSB_TXCSR_AUTOSET
2109 			| MUSB_TXCSR_DMAENAB
2110 			| MUSB_TXCSR_H_RXSTALL
2111 			| MUSB_TXCSR_H_NAKTIMEOUT
2112 			| MUSB_TXCSR_H_ERROR
2113 			| MUSB_TXCSR_TXPKTRDY);
2114 		musb_writew(epio, MUSB_TXCSR, csr);
2115 		/* REVISIT may need to clear FLUSHFIFO ... */
2116 		musb_writew(epio, MUSB_TXCSR, csr);
2117 		/* flush cpu writebuffer */
2118 		csr = musb_readw(epio, MUSB_TXCSR);
2119 	} else  {
2120 		musb_h_ep0_flush_fifo(ep);
2121 	}
2122 	if (status == 0)
2123 		musb_advance_schedule(ep->musb, urb, ep, is_in);
2124 	return status;
2125 }
2126 
2127 static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
2128 {
2129 	struct musb		*musb = hcd_to_musb(hcd);
2130 	struct musb_qh		*qh;
2131 	unsigned long		flags;
2132 	int			is_in  = usb_pipein(urb->pipe);
2133 	int			ret;
2134 
2135 	dev_dbg(musb->controller, "urb=%p, dev%d ep%d%s\n", urb,
2136 			usb_pipedevice(urb->pipe),
2137 			usb_pipeendpoint(urb->pipe),
2138 			is_in ? "in" : "out");
2139 
2140 	spin_lock_irqsave(&musb->lock, flags);
2141 	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
2142 	if (ret)
2143 		goto done;
2144 
2145 	qh = urb->hcpriv;
2146 	if (!qh)
2147 		goto done;
2148 
2149 	/*
2150 	 * Any URB not actively programmed into endpoint hardware can be
2151 	 * immediately given back; that's any URB not at the head of an
2152 	 * endpoint queue, unless someday we get real DMA queues.  And even
2153 	 * if it's at the head, it might not be known to the hardware...
2154 	 *
2155 	 * Otherwise abort current transfer, pending DMA, etc.; urb->status
2156 	 * has already been updated.  This is a synchronous abort; it'd be
2157 	 * OK to hold off until after some IRQ, though.
2158 	 *
2159 	 * NOTE: qh is invalid unless !list_empty(&hep->urb_list)
2160 	 */
2161 	if (!qh->is_ready
2162 			|| urb->urb_list.prev != &qh->hep->urb_list
2163 			|| musb_ep_get_qh(qh->hw_ep, is_in) != qh) {
2164 		int	ready = qh->is_ready;
2165 
2166 		qh->is_ready = 0;
2167 		musb_giveback(musb, urb, 0);
2168 		qh->is_ready = ready;
2169 
2170 		/* If nothing else (usually musb_giveback) is using it
2171 		 * and its URB list has emptied, recycle this qh.
2172 		 */
2173 		if (ready && list_empty(&qh->hep->urb_list)) {
2174 			qh->hep->hcpriv = NULL;
2175 			list_del(&qh->ring);
2176 			kfree(qh);
2177 		}
2178 	} else
2179 		ret = musb_cleanup_urb(urb, qh);
2180 done:
2181 	spin_unlock_irqrestore(&musb->lock, flags);
2182 	return ret;
2183 }
2184 
2185 /* disable an endpoint */
2186 static void
2187 musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
2188 {
2189 	u8			is_in = hep->desc.bEndpointAddress & USB_DIR_IN;
2190 	unsigned long		flags;
2191 	struct musb		*musb = hcd_to_musb(hcd);
2192 	struct musb_qh		*qh;
2193 	struct urb		*urb;
2194 
2195 	spin_lock_irqsave(&musb->lock, flags);
2196 
2197 	qh = hep->hcpriv;
2198 	if (qh == NULL)
2199 		goto exit;
2200 
2201 	/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
2202 
2203 	/* Kick the first URB off the hardware, if needed */
2204 	qh->is_ready = 0;
2205 	if (musb_ep_get_qh(qh->hw_ep, is_in) == qh) {
2206 		urb = next_urb(qh);
2207 
2208 		/* make software (then hardware) stop ASAP */
2209 		if (!urb->unlinked)
2210 			urb->status = -ESHUTDOWN;
2211 
2212 		/* cleanup */
2213 		musb_cleanup_urb(urb, qh);
2214 
2215 		/* Then nuke all the others ... and advance the
2216 		 * queue on hw_ep (e.g. bulk ring) when we're done.
2217 		 */
2218 		while (!list_empty(&hep->urb_list)) {
2219 			urb = next_urb(qh);
2220 			urb->status = -ESHUTDOWN;
2221 			musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
2222 		}
2223 	} else {
2224 		/* Just empty the queue; the hardware is busy with
2225 		 * other transfers, and since !qh->is_ready nothing
2226 		 * will activate any of these as it advances.
2227 		 */
2228 		while (!list_empty(&hep->urb_list))
2229 			musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
2230 
2231 		hep->hcpriv = NULL;
2232 		list_del(&qh->ring);
2233 		kfree(qh);
2234 	}
2235 exit:
2236 	spin_unlock_irqrestore(&musb->lock, flags);
2237 }
2238 
2239 static int musb_h_get_frame_number(struct usb_hcd *hcd)
2240 {
2241 	struct musb	*musb = hcd_to_musb(hcd);
2242 
2243 	return musb_readw(musb->mregs, MUSB_FRAME);
2244 }
2245 
2246 static int musb_h_start(struct usb_hcd *hcd)
2247 {
2248 	struct musb	*musb = hcd_to_musb(hcd);
2249 
2250 	/* NOTE: musb_start() is called when the hub driver turns
2251 	 * on port power, or when (OTG) peripheral starts.
2252 	 */
2253 	hcd->state = HC_STATE_RUNNING;
2254 	musb->port1_status = 0;
2255 	return 0;
2256 }
2257 
2258 static void musb_h_stop(struct usb_hcd *hcd)
2259 {
2260 	musb_stop(hcd_to_musb(hcd));
2261 	hcd->state = HC_STATE_HALT;
2262 }
2263 
2264 static int musb_bus_suspend(struct usb_hcd *hcd)
2265 {
2266 	struct musb	*musb = hcd_to_musb(hcd);
2267 	u8		devctl;
2268 
2269 	if (!is_host_active(musb))
2270 		return 0;
2271 
2272 	switch (musb->xceiv->state) {
2273 	case OTG_STATE_A_SUSPEND:
2274 		return 0;
2275 	case OTG_STATE_A_WAIT_VRISE:
2276 		/* ID could be grounded even if there's no device
2277 		 * on the other end of the cable.  NOTE that the
2278 		 * A_WAIT_VRISE timers are messy with MUSB...
2279 		 */
2280 		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2281 		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2282 			musb->xceiv->state = OTG_STATE_A_WAIT_BCON;
2283 		break;
2284 	default:
2285 		break;
2286 	}
2287 
2288 	if (musb->is_active) {
2289 		WARNING("trying to suspend as %s while active\n",
2290 				otg_state_string(musb->xceiv->state));
2291 		return -EBUSY;
2292 	} else
2293 		return 0;
2294 }
2295 
2296 static int musb_bus_resume(struct usb_hcd *hcd)
2297 {
2298 	/* resuming child port does the work */
2299 	return 0;
2300 }
2301 
2302 const struct hc_driver musb_hc_driver = {
2303 	.description		= "musb-hcd",
2304 	.product_desc		= "MUSB HDRC host driver",
2305 	.hcd_priv_size		= sizeof(struct musb),
2306 	.flags			= HCD_USB2 | HCD_MEMORY,
2307 
2308 	/* not using irq handler or reset hooks from usbcore, since
2309 	 * those must be shared with peripheral code for OTG configs
2310 	 */
2311 
2312 	.start			= musb_h_start,
2313 	.stop			= musb_h_stop,
2314 
2315 	.get_frame_number	= musb_h_get_frame_number,
2316 
2317 	.urb_enqueue		= musb_urb_enqueue,
2318 	.urb_dequeue		= musb_urb_dequeue,
2319 	.endpoint_disable	= musb_h_disable,
2320 
2321 	.hub_status_data	= musb_hub_status_data,
2322 	.hub_control		= musb_hub_control,
2323 	.bus_suspend		= musb_bus_suspend,
2324 	.bus_resume		= musb_bus_resume,
2325 	/* .start_port_reset	= NULL, */
2326 	/* .hub_irq_enable	= NULL, */
2327 };
2328