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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/list.h>
43 #include <linux/dma-mapping.h>
44 
45 #include "musb_core.h"
46 #include "musb_host.h"
47 #include "musb_trace.h"
48 
49 /* MUSB HOST status 22-mar-2006
50  *
51  * - There's still lots of partial code duplication for fault paths, so
52  *   they aren't handled as consistently as they need to be.
53  *
54  * - PIO mostly behaved when last tested.
55  *     + including ep0, with all usbtest cases 9, 10
56  *     + usbtest 14 (ep0out) doesn't seem to run at all
57  *     + double buffered OUT/TX endpoints saw stalls(!) with certain usbtest
58  *       configurations, but otherwise double buffering passes basic tests.
59  *     + for 2.6.N, for N > ~10, needs API changes for hcd framework.
60  *
61  * - DMA (CPPI) ... partially behaves, not currently recommended
62  *     + about 1/15 the speed of typical EHCI implementations (PCI)
63  *     + RX, all too often reqpkt seems to misbehave after tx
64  *     + TX, no known issues (other than evident silicon issue)
65  *
66  * - DMA (Mentor/OMAP) ...has at least toggle update problems
67  *
68  * - [23-feb-2009] minimal traffic scheduling to avoid bulk RX packet
69  *   starvation ... nothing yet for TX, interrupt, or bulk.
70  *
71  * - Not tested with HNP, but some SRP paths seem to behave.
72  *
73  * NOTE 24-August-2006:
74  *
75  * - Bulk traffic finally uses both sides of hardware ep1, freeing up an
76  *   extra endpoint for periodic use enabling hub + keybd + mouse.  That
77  *   mostly works, except that with "usbnet" it's easy to trigger cases
78  *   with "ping" where RX loses.  (a) ping to davinci, even "ping -f",
79  *   fine; but (b) ping _from_ davinci, even "ping -c 1", ICMP RX loses
80  *   although ARP RX wins.  (That test was done with a full speed link.)
81  */
82 
83 
84 /*
85  * NOTE on endpoint usage:
86  *
87  * CONTROL transfers all go through ep0.  BULK ones go through dedicated IN
88  * and OUT endpoints ... hardware is dedicated for those "async" queue(s).
89  * (Yes, bulk _could_ use more of the endpoints than that, and would even
90  * benefit from it.)
91  *
92  * INTERUPPT and ISOCHRONOUS transfers are scheduled to the other endpoints.
93  * So far that scheduling is both dumb and optimistic:  the endpoint will be
94  * "claimed" until its software queue is no longer refilled.  No multiplexing
95  * of transfers between endpoints, or anything clever.
96  */
97 
hcd_to_musb(struct usb_hcd * hcd)98 struct musb *hcd_to_musb(struct usb_hcd *hcd)
99 {
100 	return *(struct musb **) hcd->hcd_priv;
101 }
102 
103 
104 static void musb_ep_program(struct musb *musb, u8 epnum,
105 			struct urb *urb, int is_out,
106 			u8 *buf, u32 offset, u32 len);
107 
108 /*
109  * Clear TX fifo. Needed to avoid BABBLE errors.
110  */
musb_h_tx_flush_fifo(struct musb_hw_ep * ep)111 static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
112 {
113 	struct musb	*musb = ep->musb;
114 	void __iomem	*epio = ep->regs;
115 	u16		csr;
116 	int		retries = 1000;
117 
118 	csr = musb_readw(epio, MUSB_TXCSR);
119 	while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
120 		csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_TXPKTRDY;
121 		musb_writew(epio, MUSB_TXCSR, csr);
122 		csr = musb_readw(epio, MUSB_TXCSR);
123 
124 		/*
125 		 * FIXME: sometimes the tx fifo flush failed, it has been
126 		 * observed during device disconnect on AM335x.
127 		 *
128 		 * To reproduce the issue, ensure tx urb(s) are queued when
129 		 * unplug the usb device which is connected to AM335x usb
130 		 * host port.
131 		 *
132 		 * I found using a usb-ethernet device and running iperf
133 		 * (client on AM335x) has very high chance to trigger it.
134 		 *
135 		 * Better to turn on musb_dbg() in musb_cleanup_urb() with
136 		 * CPPI enabled to see the issue when aborting the tx channel.
137 		 */
138 		if (dev_WARN_ONCE(musb->controller, retries-- < 1,
139 				"Could not flush host TX%d fifo: csr: %04x\n",
140 				ep->epnum, csr))
141 			return;
142 		mdelay(1);
143 	}
144 }
145 
musb_h_ep0_flush_fifo(struct musb_hw_ep * ep)146 static void musb_h_ep0_flush_fifo(struct musb_hw_ep *ep)
147 {
148 	void __iomem	*epio = ep->regs;
149 	u16		csr;
150 	int		retries = 5;
151 
152 	/* scrub any data left in the fifo */
153 	do {
154 		csr = musb_readw(epio, MUSB_TXCSR);
155 		if (!(csr & (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_RXPKTRDY)))
156 			break;
157 		musb_writew(epio, MUSB_TXCSR, MUSB_CSR0_FLUSHFIFO);
158 		csr = musb_readw(epio, MUSB_TXCSR);
159 		udelay(10);
160 	} while (--retries);
161 
162 	WARN(!retries, "Could not flush host TX%d fifo: csr: %04x\n",
163 			ep->epnum, csr);
164 
165 	/* and reset for the next transfer */
166 	musb_writew(epio, MUSB_TXCSR, 0);
167 }
168 
169 /*
170  * Start transmit. Caller is responsible for locking shared resources.
171  * musb must be locked.
172  */
musb_h_tx_start(struct musb_hw_ep * ep)173 static inline void musb_h_tx_start(struct musb_hw_ep *ep)
174 {
175 	u16	txcsr;
176 
177 	/* NOTE: no locks here; caller should lock and select EP */
178 	if (ep->epnum) {
179 		txcsr = musb_readw(ep->regs, MUSB_TXCSR);
180 		txcsr |= MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_H_WZC_BITS;
181 		musb_writew(ep->regs, MUSB_TXCSR, txcsr);
182 	} else {
183 		txcsr = MUSB_CSR0_H_SETUPPKT | MUSB_CSR0_TXPKTRDY;
184 		musb_writew(ep->regs, MUSB_CSR0, txcsr);
185 	}
186 
187 }
188 
musb_h_tx_dma_start(struct musb_hw_ep * ep)189 static inline void musb_h_tx_dma_start(struct musb_hw_ep *ep)
190 {
191 	u16	txcsr;
192 
193 	/* NOTE: no locks here; caller should lock and select EP */
194 	txcsr = musb_readw(ep->regs, MUSB_TXCSR);
195 	txcsr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_H_WZC_BITS;
196 	if (is_cppi_enabled(ep->musb))
197 		txcsr |= MUSB_TXCSR_DMAMODE;
198 	musb_writew(ep->regs, MUSB_TXCSR, txcsr);
199 }
200 
musb_ep_set_qh(struct musb_hw_ep * ep,int is_in,struct musb_qh * qh)201 static void musb_ep_set_qh(struct musb_hw_ep *ep, int is_in, struct musb_qh *qh)
202 {
203 	if (is_in != 0 || ep->is_shared_fifo)
204 		ep->in_qh  = qh;
205 	if (is_in == 0 || ep->is_shared_fifo)
206 		ep->out_qh = qh;
207 }
208 
musb_ep_get_qh(struct musb_hw_ep * ep,int is_in)209 static struct musb_qh *musb_ep_get_qh(struct musb_hw_ep *ep, int is_in)
210 {
211 	return is_in ? ep->in_qh : ep->out_qh;
212 }
213 
214 /*
215  * Start the URB at the front of an endpoint's queue
216  * end must be claimed from the caller.
217  *
218  * Context: controller locked, irqs blocked
219  */
220 static void
musb_start_urb(struct musb * musb,int is_in,struct musb_qh * qh)221 musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
222 {
223 	u16			frame;
224 	u32			len;
225 	void __iomem		*mbase =  musb->mregs;
226 	struct urb		*urb = next_urb(qh);
227 	void			*buf = urb->transfer_buffer;
228 	u32			offset = 0;
229 	struct musb_hw_ep	*hw_ep = qh->hw_ep;
230 	int			epnum = hw_ep->epnum;
231 
232 	/* initialize software qh state */
233 	qh->offset = 0;
234 	qh->segsize = 0;
235 
236 	/* gather right source of data */
237 	switch (qh->type) {
238 	case USB_ENDPOINT_XFER_CONTROL:
239 		/* control transfers always start with SETUP */
240 		is_in = 0;
241 		musb->ep0_stage = MUSB_EP0_START;
242 		buf = urb->setup_packet;
243 		len = 8;
244 		break;
245 	case USB_ENDPOINT_XFER_ISOC:
246 		qh->iso_idx = 0;
247 		qh->frame = 0;
248 		offset = urb->iso_frame_desc[0].offset;
249 		len = urb->iso_frame_desc[0].length;
250 		break;
251 	default:		/* bulk, interrupt */
252 		/* actual_length may be nonzero on retry paths */
253 		buf = urb->transfer_buffer + urb->actual_length;
254 		len = urb->transfer_buffer_length - urb->actual_length;
255 	}
256 
257 	trace_musb_urb_start(musb, urb);
258 
259 	/* Configure endpoint */
260 	musb_ep_set_qh(hw_ep, is_in, qh);
261 	musb_ep_program(musb, epnum, urb, !is_in, buf, offset, len);
262 
263 	/* transmit may have more work: start it when it is time */
264 	if (is_in)
265 		return;
266 
267 	/* determine if the time is right for a periodic transfer */
268 	switch (qh->type) {
269 	case USB_ENDPOINT_XFER_ISOC:
270 	case USB_ENDPOINT_XFER_INT:
271 		musb_dbg(musb, "check whether there's still time for periodic Tx");
272 		frame = musb_readw(mbase, MUSB_FRAME);
273 		/* FIXME this doesn't implement that scheduling policy ...
274 		 * or handle framecounter wrapping
275 		 */
276 		if (1) {	/* Always assume URB_ISO_ASAP */
277 			/* REVISIT the SOF irq handler shouldn't duplicate
278 			 * this code; and we don't init urb->start_frame...
279 			 */
280 			qh->frame = 0;
281 			goto start;
282 		} else {
283 			qh->frame = urb->start_frame;
284 			/* enable SOF interrupt so we can count down */
285 			musb_dbg(musb, "SOF for %d", epnum);
286 #if 1 /* ifndef	CONFIG_ARCH_DAVINCI */
287 			musb_writeb(mbase, MUSB_INTRUSBE, 0xff);
288 #endif
289 		}
290 		break;
291 	default:
292 start:
293 		musb_dbg(musb, "Start TX%d %s", epnum,
294 			hw_ep->tx_channel ? "dma" : "pio");
295 
296 		if (!hw_ep->tx_channel)
297 			musb_h_tx_start(hw_ep);
298 		else if (is_cppi_enabled(musb) || tusb_dma_omap(musb))
299 			musb_h_tx_dma_start(hw_ep);
300 	}
301 }
302 
303 /* Context: caller owns controller lock, IRQs are blocked */
musb_giveback(struct musb * musb,struct urb * urb,int status)304 static void musb_giveback(struct musb *musb, struct urb *urb, int status)
305 __releases(musb->lock)
306 __acquires(musb->lock)
307 {
308 	trace_musb_urb_gb(musb, urb);
309 
310 	usb_hcd_unlink_urb_from_ep(musb->hcd, urb);
311 	spin_unlock(&musb->lock);
312 	usb_hcd_giveback_urb(musb->hcd, urb, status);
313 	spin_lock(&musb->lock);
314 }
315 
316 /* For bulk/interrupt endpoints only */
musb_save_toggle(struct musb_qh * qh,int is_in,struct urb * urb)317 static inline void musb_save_toggle(struct musb_qh *qh, int is_in,
318 				    struct urb *urb)
319 {
320 	void __iomem		*epio = qh->hw_ep->regs;
321 	u16			csr;
322 
323 	/*
324 	 * FIXME: the current Mentor DMA code seems to have
325 	 * problems getting toggle correct.
326 	 */
327 
328 	if (is_in)
329 		csr = musb_readw(epio, MUSB_RXCSR) & MUSB_RXCSR_H_DATATOGGLE;
330 	else
331 		csr = musb_readw(epio, MUSB_TXCSR) & MUSB_TXCSR_H_DATATOGGLE;
332 
333 	usb_settoggle(urb->dev, qh->epnum, !is_in, csr ? 1 : 0);
334 }
335 
336 /*
337  * Advance this hardware endpoint's queue, completing the specified URB and
338  * advancing to either the next URB queued to that qh, or else invalidating
339  * that qh and advancing to the next qh scheduled after the current one.
340  *
341  * Context: caller owns controller lock, IRQs are blocked
342  */
musb_advance_schedule(struct musb * musb,struct urb * urb,struct musb_hw_ep * hw_ep,int is_in)343 static void musb_advance_schedule(struct musb *musb, struct urb *urb,
344 				  struct musb_hw_ep *hw_ep, int is_in)
345 {
346 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, is_in);
347 	struct musb_hw_ep	*ep = qh->hw_ep;
348 	int			ready = qh->is_ready;
349 	int			status;
350 
351 	status = (urb->status == -EINPROGRESS) ? 0 : urb->status;
352 
353 	/* save toggle eagerly, for paranoia */
354 	switch (qh->type) {
355 	case USB_ENDPOINT_XFER_BULK:
356 	case USB_ENDPOINT_XFER_INT:
357 		musb_save_toggle(qh, is_in, urb);
358 		break;
359 	case USB_ENDPOINT_XFER_ISOC:
360 		if (status == 0 && urb->error_count)
361 			status = -EXDEV;
362 		break;
363 	}
364 
365 	qh->is_ready = 0;
366 	musb_giveback(musb, urb, status);
367 	qh->is_ready = ready;
368 
369 	/* reclaim resources (and bandwidth) ASAP; deschedule it, and
370 	 * invalidate qh as soon as list_empty(&hep->urb_list)
371 	 */
372 	if (list_empty(&qh->hep->urb_list)) {
373 		struct list_head	*head;
374 		struct dma_controller	*dma = musb->dma_controller;
375 
376 		if (is_in) {
377 			ep->rx_reinit = 1;
378 			if (ep->rx_channel) {
379 				dma->channel_release(ep->rx_channel);
380 				ep->rx_channel = NULL;
381 			}
382 		} else {
383 			ep->tx_reinit = 1;
384 			if (ep->tx_channel) {
385 				dma->channel_release(ep->tx_channel);
386 				ep->tx_channel = NULL;
387 			}
388 		}
389 
390 		/* Clobber old pointers to this qh */
391 		musb_ep_set_qh(ep, is_in, NULL);
392 		qh->hep->hcpriv = NULL;
393 
394 		switch (qh->type) {
395 
396 		case USB_ENDPOINT_XFER_CONTROL:
397 		case USB_ENDPOINT_XFER_BULK:
398 			/* fifo policy for these lists, except that NAKing
399 			 * should rotate a qh to the end (for fairness).
400 			 */
401 			if (qh->mux == 1) {
402 				head = qh->ring.prev;
403 				list_del(&qh->ring);
404 				kfree(qh);
405 				qh = first_qh(head);
406 				break;
407 			}
408 
409 		case USB_ENDPOINT_XFER_ISOC:
410 		case USB_ENDPOINT_XFER_INT:
411 			/* this is where periodic bandwidth should be
412 			 * de-allocated if it's tracked and allocated;
413 			 * and where we'd update the schedule tree...
414 			 */
415 			kfree(qh);
416 			qh = NULL;
417 			break;
418 		}
419 	}
420 
421 	if (qh != NULL && qh->is_ready) {
422 		musb_dbg(musb, "... next ep%d %cX urb %p",
423 		    hw_ep->epnum, is_in ? 'R' : 'T', next_urb(qh));
424 		musb_start_urb(musb, is_in, qh);
425 	}
426 }
427 
musb_h_flush_rxfifo(struct musb_hw_ep * hw_ep,u16 csr)428 static u16 musb_h_flush_rxfifo(struct musb_hw_ep *hw_ep, u16 csr)
429 {
430 	/* we don't want fifo to fill itself again;
431 	 * ignore dma (various models),
432 	 * leave toggle alone (may not have been saved yet)
433 	 */
434 	csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_RXPKTRDY;
435 	csr &= ~(MUSB_RXCSR_H_REQPKT
436 		| MUSB_RXCSR_H_AUTOREQ
437 		| MUSB_RXCSR_AUTOCLEAR);
438 
439 	/* write 2x to allow double buffering */
440 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
441 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
442 
443 	/* flush writebuffer */
444 	return musb_readw(hw_ep->regs, MUSB_RXCSR);
445 }
446 
447 /*
448  * PIO RX for a packet (or part of it).
449  */
450 static bool
musb_host_packet_rx(struct musb * musb,struct urb * urb,u8 epnum,u8 iso_err)451 musb_host_packet_rx(struct musb *musb, struct urb *urb, u8 epnum, u8 iso_err)
452 {
453 	u16			rx_count;
454 	u8			*buf;
455 	u16			csr;
456 	bool			done = false;
457 	u32			length;
458 	int			do_flush = 0;
459 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
460 	void __iomem		*epio = hw_ep->regs;
461 	struct musb_qh		*qh = hw_ep->in_qh;
462 	int			pipe = urb->pipe;
463 	void			*buffer = urb->transfer_buffer;
464 
465 	/* musb_ep_select(mbase, epnum); */
466 	rx_count = musb_readw(epio, MUSB_RXCOUNT);
467 	musb_dbg(musb, "RX%d count %d, buffer %p len %d/%d", epnum, rx_count,
468 			urb->transfer_buffer, qh->offset,
469 			urb->transfer_buffer_length);
470 
471 	/* unload FIFO */
472 	if (usb_pipeisoc(pipe)) {
473 		int					status = 0;
474 		struct usb_iso_packet_descriptor	*d;
475 
476 		if (iso_err) {
477 			status = -EILSEQ;
478 			urb->error_count++;
479 		}
480 
481 		d = urb->iso_frame_desc + qh->iso_idx;
482 		buf = buffer + d->offset;
483 		length = d->length;
484 		if (rx_count > length) {
485 			if (status == 0) {
486 				status = -EOVERFLOW;
487 				urb->error_count++;
488 			}
489 			musb_dbg(musb, "OVERFLOW %d into %d", rx_count, length);
490 			do_flush = 1;
491 		} else
492 			length = rx_count;
493 		urb->actual_length += length;
494 		d->actual_length = length;
495 
496 		d->status = status;
497 
498 		/* see if we are done */
499 		done = (++qh->iso_idx >= urb->number_of_packets);
500 	} else {
501 		/* non-isoch */
502 		buf = buffer + qh->offset;
503 		length = urb->transfer_buffer_length - qh->offset;
504 		if (rx_count > length) {
505 			if (urb->status == -EINPROGRESS)
506 				urb->status = -EOVERFLOW;
507 			musb_dbg(musb, "OVERFLOW %d into %d", rx_count, length);
508 			do_flush = 1;
509 		} else
510 			length = rx_count;
511 		urb->actual_length += length;
512 		qh->offset += length;
513 
514 		/* see if we are done */
515 		done = (urb->actual_length == urb->transfer_buffer_length)
516 			|| (rx_count < qh->maxpacket)
517 			|| (urb->status != -EINPROGRESS);
518 		if (done
519 				&& (urb->status == -EINPROGRESS)
520 				&& (urb->transfer_flags & URB_SHORT_NOT_OK)
521 				&& (urb->actual_length
522 					< urb->transfer_buffer_length))
523 			urb->status = -EREMOTEIO;
524 	}
525 
526 	musb_read_fifo(hw_ep, length, buf);
527 
528 	csr = musb_readw(epio, MUSB_RXCSR);
529 	csr |= MUSB_RXCSR_H_WZC_BITS;
530 	if (unlikely(do_flush))
531 		musb_h_flush_rxfifo(hw_ep, csr);
532 	else {
533 		/* REVISIT this assumes AUTOCLEAR is never set */
534 		csr &= ~(MUSB_RXCSR_RXPKTRDY | MUSB_RXCSR_H_REQPKT);
535 		if (!done)
536 			csr |= MUSB_RXCSR_H_REQPKT;
537 		musb_writew(epio, MUSB_RXCSR, csr);
538 	}
539 
540 	return done;
541 }
542 
543 /* we don't always need to reinit a given side of an endpoint...
544  * when we do, use tx/rx reinit routine and then construct a new CSR
545  * to address data toggle, NYET, and DMA or PIO.
546  *
547  * it's possible that driver bugs (especially for DMA) or aborting a
548  * transfer might have left the endpoint busier than it should be.
549  * the busy/not-empty tests are basically paranoia.
550  */
551 static void
musb_rx_reinit(struct musb * musb,struct musb_qh * qh,u8 epnum)552 musb_rx_reinit(struct musb *musb, struct musb_qh *qh, u8 epnum)
553 {
554 	struct musb_hw_ep *ep = musb->endpoints + epnum;
555 	u16	csr;
556 
557 	/* NOTE:  we know the "rx" fifo reinit never triggers for ep0.
558 	 * That always uses tx_reinit since ep0 repurposes TX register
559 	 * offsets; the initial SETUP packet is also a kind of OUT.
560 	 */
561 
562 	/* if programmed for Tx, put it in RX mode */
563 	if (ep->is_shared_fifo) {
564 		csr = musb_readw(ep->regs, MUSB_TXCSR);
565 		if (csr & MUSB_TXCSR_MODE) {
566 			musb_h_tx_flush_fifo(ep);
567 			csr = musb_readw(ep->regs, MUSB_TXCSR);
568 			musb_writew(ep->regs, MUSB_TXCSR,
569 				    csr | MUSB_TXCSR_FRCDATATOG);
570 		}
571 
572 		/*
573 		 * Clear the MODE bit (and everything else) to enable Rx.
574 		 * NOTE: we mustn't clear the DMAMODE bit before DMAENAB.
575 		 */
576 		if (csr & MUSB_TXCSR_DMAMODE)
577 			musb_writew(ep->regs, MUSB_TXCSR, MUSB_TXCSR_DMAMODE);
578 		musb_writew(ep->regs, MUSB_TXCSR, 0);
579 
580 	/* scrub all previous state, clearing toggle */
581 	}
582 	csr = musb_readw(ep->regs, MUSB_RXCSR);
583 	if (csr & MUSB_RXCSR_RXPKTRDY)
584 		WARNING("rx%d, packet/%d ready?\n", ep->epnum,
585 			musb_readw(ep->regs, MUSB_RXCOUNT));
586 
587 	musb_h_flush_rxfifo(ep, MUSB_RXCSR_CLRDATATOG);
588 
589 	/* target addr and (for multipoint) hub addr/port */
590 	if (musb->is_multipoint) {
591 		musb_write_rxfunaddr(musb, epnum, qh->addr_reg);
592 		musb_write_rxhubaddr(musb, epnum, qh->h_addr_reg);
593 		musb_write_rxhubport(musb, epnum, qh->h_port_reg);
594 	} else
595 		musb_writeb(musb->mregs, MUSB_FADDR, qh->addr_reg);
596 
597 	/* protocol/endpoint, interval/NAKlimit, i/o size */
598 	musb_writeb(ep->regs, MUSB_RXTYPE, qh->type_reg);
599 	musb_writeb(ep->regs, MUSB_RXINTERVAL, qh->intv_reg);
600 	/* NOTE: bulk combining rewrites high bits of maxpacket */
601 	/* Set RXMAXP with the FIFO size of the endpoint
602 	 * to disable double buffer mode.
603 	 */
604 	if (musb->double_buffer_not_ok)
605 		musb_writew(ep->regs, MUSB_RXMAXP, ep->max_packet_sz_rx);
606 	else
607 		musb_writew(ep->regs, MUSB_RXMAXP,
608 				qh->maxpacket | ((qh->hb_mult - 1) << 11));
609 
610 	ep->rx_reinit = 0;
611 }
612 
musb_tx_dma_set_mode_mentor(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,u32 offset,u32 * length,u8 * mode)613 static void musb_tx_dma_set_mode_mentor(struct dma_controller *dma,
614 		struct musb_hw_ep *hw_ep, struct musb_qh *qh,
615 		struct urb *urb, u32 offset,
616 		u32 *length, u8 *mode)
617 {
618 	struct dma_channel	*channel = hw_ep->tx_channel;
619 	void __iomem		*epio = hw_ep->regs;
620 	u16			pkt_size = qh->maxpacket;
621 	u16			csr;
622 
623 	if (*length > channel->max_len)
624 		*length = channel->max_len;
625 
626 	csr = musb_readw(epio, MUSB_TXCSR);
627 	if (*length > pkt_size) {
628 		*mode = 1;
629 		csr |= MUSB_TXCSR_DMAMODE | MUSB_TXCSR_DMAENAB;
630 		/* autoset shouldn't be set in high bandwidth */
631 		/*
632 		 * Enable Autoset according to table
633 		 * below
634 		 * bulk_split hb_mult	Autoset_Enable
635 		 *	0	1	Yes(Normal)
636 		 *	0	>1	No(High BW ISO)
637 		 *	1	1	Yes(HS bulk)
638 		 *	1	>1	Yes(FS bulk)
639 		 */
640 		if (qh->hb_mult == 1 || (qh->hb_mult > 1 &&
641 					can_bulk_split(hw_ep->musb, qh->type)))
642 			csr |= MUSB_TXCSR_AUTOSET;
643 	} else {
644 		*mode = 0;
645 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAMODE);
646 		csr |= MUSB_TXCSR_DMAENAB; /* against programmer's guide */
647 	}
648 	channel->desired_mode = *mode;
649 	musb_writew(epio, MUSB_TXCSR, csr);
650 }
651 
musb_tx_dma_set_mode_cppi_tusb(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,u32 offset,u32 * length,u8 * mode)652 static void musb_tx_dma_set_mode_cppi_tusb(struct dma_controller *dma,
653 					   struct musb_hw_ep *hw_ep,
654 					   struct musb_qh *qh,
655 					   struct urb *urb,
656 					   u32 offset,
657 					   u32 *length,
658 					   u8 *mode)
659 {
660 	struct dma_channel *channel = hw_ep->tx_channel;
661 
662 	channel->actual_len = 0;
663 
664 	/*
665 	 * TX uses "RNDIS" mode automatically but needs help
666 	 * to identify the zero-length-final-packet case.
667 	 */
668 	*mode = (urb->transfer_flags & URB_ZERO_PACKET) ? 1 : 0;
669 }
670 
musb_tx_dma_program(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,u32 offset,u32 length)671 static bool musb_tx_dma_program(struct dma_controller *dma,
672 		struct musb_hw_ep *hw_ep, struct musb_qh *qh,
673 		struct urb *urb, u32 offset, u32 length)
674 {
675 	struct dma_channel	*channel = hw_ep->tx_channel;
676 	u16			pkt_size = qh->maxpacket;
677 	u8			mode;
678 
679 	if (musb_dma_inventra(hw_ep->musb) || musb_dma_ux500(hw_ep->musb))
680 		musb_tx_dma_set_mode_mentor(dma, hw_ep, qh, urb, offset,
681 					    &length, &mode);
682 	else if (is_cppi_enabled(hw_ep->musb) || tusb_dma_omap(hw_ep->musb))
683 		musb_tx_dma_set_mode_cppi_tusb(dma, hw_ep, qh, urb, offset,
684 					       &length, &mode);
685 	else
686 		return false;
687 
688 	qh->segsize = length;
689 
690 	/*
691 	 * Ensure the data reaches to main memory before starting
692 	 * DMA transfer
693 	 */
694 	wmb();
695 
696 	if (!dma->channel_program(channel, pkt_size, mode,
697 			urb->transfer_dma + offset, length)) {
698 		void __iomem *epio = hw_ep->regs;
699 		u16 csr;
700 
701 		dma->channel_release(channel);
702 		hw_ep->tx_channel = NULL;
703 
704 		csr = musb_readw(epio, MUSB_TXCSR);
705 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
706 		musb_writew(epio, MUSB_TXCSR, csr | MUSB_TXCSR_H_WZC_BITS);
707 		return false;
708 	}
709 	return true;
710 }
711 
712 /*
713  * Program an HDRC endpoint as per the given URB
714  * Context: irqs blocked, controller lock held
715  */
musb_ep_program(struct musb * musb,u8 epnum,struct urb * urb,int is_out,u8 * buf,u32 offset,u32 len)716 static void musb_ep_program(struct musb *musb, u8 epnum,
717 			struct urb *urb, int is_out,
718 			u8 *buf, u32 offset, u32 len)
719 {
720 	struct dma_controller	*dma_controller;
721 	struct dma_channel	*dma_channel;
722 	u8			dma_ok;
723 	void __iomem		*mbase = musb->mregs;
724 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
725 	void __iomem		*epio = hw_ep->regs;
726 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, !is_out);
727 	u16			packet_sz = qh->maxpacket;
728 	u8			use_dma = 1;
729 	u16			csr;
730 
731 	musb_dbg(musb, "%s hw%d urb %p spd%d dev%d ep%d%s "
732 				"h_addr%02x h_port%02x bytes %d",
733 			is_out ? "-->" : "<--",
734 			epnum, urb, urb->dev->speed,
735 			qh->addr_reg, qh->epnum, is_out ? "out" : "in",
736 			qh->h_addr_reg, qh->h_port_reg,
737 			len);
738 
739 	musb_ep_select(mbase, epnum);
740 
741 	if (is_out && !len) {
742 		use_dma = 0;
743 		csr = musb_readw(epio, MUSB_TXCSR);
744 		csr &= ~MUSB_TXCSR_DMAENAB;
745 		musb_writew(epio, MUSB_TXCSR, csr);
746 		hw_ep->tx_channel = NULL;
747 	}
748 
749 	/* candidate for DMA? */
750 	dma_controller = musb->dma_controller;
751 	if (use_dma && is_dma_capable() && epnum && dma_controller) {
752 		dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel;
753 		if (!dma_channel) {
754 			dma_channel = dma_controller->channel_alloc(
755 					dma_controller, hw_ep, is_out);
756 			if (is_out)
757 				hw_ep->tx_channel = dma_channel;
758 			else
759 				hw_ep->rx_channel = dma_channel;
760 		}
761 	} else
762 		dma_channel = NULL;
763 
764 	/* make sure we clear DMAEnab, autoSet bits from previous run */
765 
766 	/* OUT/transmit/EP0 or IN/receive? */
767 	if (is_out) {
768 		u16	csr;
769 		u16	int_txe;
770 		u16	load_count;
771 
772 		csr = musb_readw(epio, MUSB_TXCSR);
773 
774 		/* disable interrupt in case we flush */
775 		int_txe = musb->intrtxe;
776 		musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
777 
778 		/* general endpoint setup */
779 		if (epnum) {
780 			/* flush all old state, set default */
781 			/*
782 			 * We could be flushing valid
783 			 * packets in double buffering
784 			 * case
785 			 */
786 			if (!hw_ep->tx_double_buffered)
787 				musb_h_tx_flush_fifo(hw_ep);
788 
789 			/*
790 			 * We must not clear the DMAMODE bit before or in
791 			 * the same cycle with the DMAENAB bit, so we clear
792 			 * the latter first...
793 			 */
794 			csr &= ~(MUSB_TXCSR_H_NAKTIMEOUT
795 					| MUSB_TXCSR_AUTOSET
796 					| MUSB_TXCSR_DMAENAB
797 					| MUSB_TXCSR_FRCDATATOG
798 					| MUSB_TXCSR_H_RXSTALL
799 					| MUSB_TXCSR_H_ERROR
800 					| MUSB_TXCSR_TXPKTRDY
801 					);
802 			csr |= MUSB_TXCSR_MODE;
803 
804 			if (!hw_ep->tx_double_buffered) {
805 				if (usb_gettoggle(urb->dev, qh->epnum, 1))
806 					csr |= MUSB_TXCSR_H_WR_DATATOGGLE
807 						| MUSB_TXCSR_H_DATATOGGLE;
808 				else
809 					csr |= MUSB_TXCSR_CLRDATATOG;
810 			}
811 
812 			musb_writew(epio, MUSB_TXCSR, csr);
813 			/* REVISIT may need to clear FLUSHFIFO ... */
814 			csr &= ~MUSB_TXCSR_DMAMODE;
815 			musb_writew(epio, MUSB_TXCSR, csr);
816 			csr = musb_readw(epio, MUSB_TXCSR);
817 		} else {
818 			/* endpoint 0: just flush */
819 			musb_h_ep0_flush_fifo(hw_ep);
820 		}
821 
822 		/* target addr and (for multipoint) hub addr/port */
823 		if (musb->is_multipoint) {
824 			musb_write_txfunaddr(musb, epnum, qh->addr_reg);
825 			musb_write_txhubaddr(musb, epnum, qh->h_addr_reg);
826 			musb_write_txhubport(musb, epnum, qh->h_port_reg);
827 /* FIXME if !epnum, do the same for RX ... */
828 		} else
829 			musb_writeb(mbase, MUSB_FADDR, qh->addr_reg);
830 
831 		/* protocol/endpoint/interval/NAKlimit */
832 		if (epnum) {
833 			musb_writeb(epio, MUSB_TXTYPE, qh->type_reg);
834 			if (musb->double_buffer_not_ok) {
835 				musb_writew(epio, MUSB_TXMAXP,
836 						hw_ep->max_packet_sz_tx);
837 			} else if (can_bulk_split(musb, qh->type)) {
838 				qh->hb_mult = hw_ep->max_packet_sz_tx
839 						/ packet_sz;
840 				musb_writew(epio, MUSB_TXMAXP, packet_sz
841 					| ((qh->hb_mult) - 1) << 11);
842 			} else {
843 				musb_writew(epio, MUSB_TXMAXP,
844 						qh->maxpacket |
845 						((qh->hb_mult - 1) << 11));
846 			}
847 			musb_writeb(epio, MUSB_TXINTERVAL, qh->intv_reg);
848 		} else {
849 			musb_writeb(epio, MUSB_NAKLIMIT0, qh->intv_reg);
850 			if (musb->is_multipoint)
851 				musb_writeb(epio, MUSB_TYPE0,
852 						qh->type_reg);
853 		}
854 
855 		if (can_bulk_split(musb, qh->type))
856 			load_count = min((u32) hw_ep->max_packet_sz_tx,
857 						len);
858 		else
859 			load_count = min((u32) packet_sz, len);
860 
861 		if (dma_channel && musb_tx_dma_program(dma_controller,
862 					hw_ep, qh, urb, offset, len))
863 			load_count = 0;
864 
865 		if (load_count) {
866 			/* PIO to load FIFO */
867 			qh->segsize = load_count;
868 			if (!buf) {
869 				sg_miter_start(&qh->sg_miter, urb->sg, 1,
870 						SG_MITER_ATOMIC
871 						| SG_MITER_FROM_SG);
872 				if (!sg_miter_next(&qh->sg_miter)) {
873 					dev_err(musb->controller,
874 							"error: sg"
875 							"list empty\n");
876 					sg_miter_stop(&qh->sg_miter);
877 					goto finish;
878 				}
879 				buf = qh->sg_miter.addr + urb->sg->offset +
880 					urb->actual_length;
881 				load_count = min_t(u32, load_count,
882 						qh->sg_miter.length);
883 				musb_write_fifo(hw_ep, load_count, buf);
884 				qh->sg_miter.consumed = load_count;
885 				sg_miter_stop(&qh->sg_miter);
886 			} else
887 				musb_write_fifo(hw_ep, load_count, buf);
888 		}
889 finish:
890 		/* re-enable interrupt */
891 		musb_writew(mbase, MUSB_INTRTXE, int_txe);
892 
893 	/* IN/receive */
894 	} else {
895 		u16	csr;
896 
897 		if (hw_ep->rx_reinit) {
898 			musb_rx_reinit(musb, qh, epnum);
899 
900 			/* init new state: toggle and NYET, maybe DMA later */
901 			if (usb_gettoggle(urb->dev, qh->epnum, 0))
902 				csr = MUSB_RXCSR_H_WR_DATATOGGLE
903 					| MUSB_RXCSR_H_DATATOGGLE;
904 			else
905 				csr = 0;
906 			if (qh->type == USB_ENDPOINT_XFER_INT)
907 				csr |= MUSB_RXCSR_DISNYET;
908 
909 		} else {
910 			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
911 
912 			if (csr & (MUSB_RXCSR_RXPKTRDY
913 					| MUSB_RXCSR_DMAENAB
914 					| MUSB_RXCSR_H_REQPKT))
915 				ERR("broken !rx_reinit, ep%d csr %04x\n",
916 						hw_ep->epnum, csr);
917 
918 			/* scrub any stale state, leaving toggle alone */
919 			csr &= MUSB_RXCSR_DISNYET;
920 		}
921 
922 		/* kick things off */
923 
924 		if ((is_cppi_enabled(musb) || tusb_dma_omap(musb)) && dma_channel) {
925 			/* Candidate for DMA */
926 			dma_channel->actual_len = 0L;
927 			qh->segsize = len;
928 
929 			/* AUTOREQ is in a DMA register */
930 			musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
931 			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
932 
933 			/*
934 			 * Unless caller treats short RX transfers as
935 			 * errors, we dare not queue multiple transfers.
936 			 */
937 			dma_ok = dma_controller->channel_program(dma_channel,
938 					packet_sz, !(urb->transfer_flags &
939 						     URB_SHORT_NOT_OK),
940 					urb->transfer_dma + offset,
941 					qh->segsize);
942 			if (!dma_ok) {
943 				dma_controller->channel_release(dma_channel);
944 				hw_ep->rx_channel = dma_channel = NULL;
945 			} else
946 				csr |= MUSB_RXCSR_DMAENAB;
947 		}
948 
949 		csr |= MUSB_RXCSR_H_REQPKT;
950 		musb_dbg(musb, "RXCSR%d := %04x", epnum, csr);
951 		musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
952 		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
953 	}
954 }
955 
956 /* Schedule next QH from musb->in_bulk/out_bulk and move the current qh to
957  * the end; avoids starvation for other endpoints.
958  */
musb_bulk_nak_timeout(struct musb * musb,struct musb_hw_ep * ep,int is_in)959 static void musb_bulk_nak_timeout(struct musb *musb, struct musb_hw_ep *ep,
960 	int is_in)
961 {
962 	struct dma_channel	*dma;
963 	struct urb		*urb;
964 	void __iomem		*mbase = musb->mregs;
965 	void __iomem		*epio = ep->regs;
966 	struct musb_qh		*cur_qh, *next_qh;
967 	u16			rx_csr, tx_csr;
968 
969 	musb_ep_select(mbase, ep->epnum);
970 	if (is_in) {
971 		dma = is_dma_capable() ? ep->rx_channel : NULL;
972 
973 		/*
974 		 * Need to stop the transaction by clearing REQPKT first
975 		 * then the NAK Timeout bit ref MUSBMHDRC USB 2.0 HIGH-SPEED
976 		 * DUAL-ROLE CONTROLLER Programmer's Guide, section 9.2.2
977 		 */
978 		rx_csr = musb_readw(epio, MUSB_RXCSR);
979 		rx_csr |= MUSB_RXCSR_H_WZC_BITS;
980 		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
981 		musb_writew(epio, MUSB_RXCSR, rx_csr);
982 		rx_csr &= ~MUSB_RXCSR_DATAERROR;
983 		musb_writew(epio, MUSB_RXCSR, rx_csr);
984 
985 		cur_qh = first_qh(&musb->in_bulk);
986 	} else {
987 		dma = is_dma_capable() ? ep->tx_channel : NULL;
988 
989 		/* clear nak timeout bit */
990 		tx_csr = musb_readw(epio, MUSB_TXCSR);
991 		tx_csr |= MUSB_TXCSR_H_WZC_BITS;
992 		tx_csr &= ~MUSB_TXCSR_H_NAKTIMEOUT;
993 		musb_writew(epio, MUSB_TXCSR, tx_csr);
994 
995 		cur_qh = first_qh(&musb->out_bulk);
996 	}
997 	if (cur_qh) {
998 		urb = next_urb(cur_qh);
999 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1000 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1001 			musb->dma_controller->channel_abort(dma);
1002 			urb->actual_length += dma->actual_len;
1003 			dma->actual_len = 0L;
1004 		}
1005 		musb_save_toggle(cur_qh, is_in, urb);
1006 
1007 		if (is_in) {
1008 			/* move cur_qh to end of queue */
1009 			list_move_tail(&cur_qh->ring, &musb->in_bulk);
1010 
1011 			/* get the next qh from musb->in_bulk */
1012 			next_qh = first_qh(&musb->in_bulk);
1013 
1014 			/* set rx_reinit and schedule the next qh */
1015 			ep->rx_reinit = 1;
1016 		} else {
1017 			/* move cur_qh to end of queue */
1018 			list_move_tail(&cur_qh->ring, &musb->out_bulk);
1019 
1020 			/* get the next qh from musb->out_bulk */
1021 			next_qh = first_qh(&musb->out_bulk);
1022 
1023 			/* set tx_reinit and schedule the next qh */
1024 			ep->tx_reinit = 1;
1025 		}
1026 
1027 		if (next_qh)
1028 			musb_start_urb(musb, is_in, next_qh);
1029 	}
1030 }
1031 
1032 /*
1033  * Service the default endpoint (ep0) as host.
1034  * Return true until it's time to start the status stage.
1035  */
musb_h_ep0_continue(struct musb * musb,u16 len,struct urb * urb)1036 static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
1037 {
1038 	bool			 more = false;
1039 	u8			*fifo_dest = NULL;
1040 	u16			fifo_count = 0;
1041 	struct musb_hw_ep	*hw_ep = musb->control_ep;
1042 	struct musb_qh		*qh = hw_ep->in_qh;
1043 	struct usb_ctrlrequest	*request;
1044 
1045 	switch (musb->ep0_stage) {
1046 	case MUSB_EP0_IN:
1047 		fifo_dest = urb->transfer_buffer + urb->actual_length;
1048 		fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
1049 				   urb->actual_length);
1050 		if (fifo_count < len)
1051 			urb->status = -EOVERFLOW;
1052 
1053 		musb_read_fifo(hw_ep, fifo_count, fifo_dest);
1054 
1055 		urb->actual_length += fifo_count;
1056 		if (len < qh->maxpacket) {
1057 			/* always terminate on short read; it's
1058 			 * rarely reported as an error.
1059 			 */
1060 		} else if (urb->actual_length <
1061 				urb->transfer_buffer_length)
1062 			more = true;
1063 		break;
1064 	case MUSB_EP0_START:
1065 		request = (struct usb_ctrlrequest *) urb->setup_packet;
1066 
1067 		if (!request->wLength) {
1068 			musb_dbg(musb, "start no-DATA");
1069 			break;
1070 		} else if (request->bRequestType & USB_DIR_IN) {
1071 			musb_dbg(musb, "start IN-DATA");
1072 			musb->ep0_stage = MUSB_EP0_IN;
1073 			more = true;
1074 			break;
1075 		} else {
1076 			musb_dbg(musb, "start OUT-DATA");
1077 			musb->ep0_stage = MUSB_EP0_OUT;
1078 			more = true;
1079 		}
1080 		/* FALLTHROUGH */
1081 	case MUSB_EP0_OUT:
1082 		fifo_count = min_t(size_t, qh->maxpacket,
1083 				   urb->transfer_buffer_length -
1084 				   urb->actual_length);
1085 		if (fifo_count) {
1086 			fifo_dest = (u8 *) (urb->transfer_buffer
1087 					+ urb->actual_length);
1088 			musb_dbg(musb, "Sending %d byte%s to ep0 fifo %p",
1089 					fifo_count,
1090 					(fifo_count == 1) ? "" : "s",
1091 					fifo_dest);
1092 			musb_write_fifo(hw_ep, fifo_count, fifo_dest);
1093 
1094 			urb->actual_length += fifo_count;
1095 			more = true;
1096 		}
1097 		break;
1098 	default:
1099 		ERR("bogus ep0 stage %d\n", musb->ep0_stage);
1100 		break;
1101 	}
1102 
1103 	return more;
1104 }
1105 
1106 /*
1107  * Handle default endpoint interrupt as host. Only called in IRQ time
1108  * from musb_interrupt().
1109  *
1110  * called with controller irqlocked
1111  */
musb_h_ep0_irq(struct musb * musb)1112 irqreturn_t musb_h_ep0_irq(struct musb *musb)
1113 {
1114 	struct urb		*urb;
1115 	u16			csr, len;
1116 	int			status = 0;
1117 	void __iomem		*mbase = musb->mregs;
1118 	struct musb_hw_ep	*hw_ep = musb->control_ep;
1119 	void __iomem		*epio = hw_ep->regs;
1120 	struct musb_qh		*qh = hw_ep->in_qh;
1121 	bool			complete = false;
1122 	irqreturn_t		retval = IRQ_NONE;
1123 
1124 	/* ep0 only has one queue, "in" */
1125 	urb = next_urb(qh);
1126 
1127 	musb_ep_select(mbase, 0);
1128 	csr = musb_readw(epio, MUSB_CSR0);
1129 	len = (csr & MUSB_CSR0_RXPKTRDY)
1130 			? musb_readb(epio, MUSB_COUNT0)
1131 			: 0;
1132 
1133 	musb_dbg(musb, "<== csr0 %04x, qh %p, count %d, urb %p, stage %d",
1134 		csr, qh, len, urb, musb->ep0_stage);
1135 
1136 	/* if we just did status stage, we are done */
1137 	if (MUSB_EP0_STATUS == musb->ep0_stage) {
1138 		retval = IRQ_HANDLED;
1139 		complete = true;
1140 	}
1141 
1142 	/* prepare status */
1143 	if (csr & MUSB_CSR0_H_RXSTALL) {
1144 		musb_dbg(musb, "STALLING ENDPOINT");
1145 		status = -EPIPE;
1146 
1147 	} else if (csr & MUSB_CSR0_H_ERROR) {
1148 		musb_dbg(musb, "no response, csr0 %04x", csr);
1149 		status = -EPROTO;
1150 
1151 	} else if (csr & MUSB_CSR0_H_NAKTIMEOUT) {
1152 		musb_dbg(musb, "control NAK timeout");
1153 
1154 		/* NOTE:  this code path would be a good place to PAUSE a
1155 		 * control transfer, if another one is queued, so that
1156 		 * ep0 is more likely to stay busy.  That's already done
1157 		 * for bulk RX transfers.
1158 		 *
1159 		 * if (qh->ring.next != &musb->control), then
1160 		 * we have a candidate... NAKing is *NOT* an error
1161 		 */
1162 		musb_writew(epio, MUSB_CSR0, 0);
1163 		retval = IRQ_HANDLED;
1164 	}
1165 
1166 	if (status) {
1167 		musb_dbg(musb, "aborting");
1168 		retval = IRQ_HANDLED;
1169 		if (urb)
1170 			urb->status = status;
1171 		complete = true;
1172 
1173 		/* use the proper sequence to abort the transfer */
1174 		if (csr & MUSB_CSR0_H_REQPKT) {
1175 			csr &= ~MUSB_CSR0_H_REQPKT;
1176 			musb_writew(epio, MUSB_CSR0, csr);
1177 			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1178 			musb_writew(epio, MUSB_CSR0, csr);
1179 		} else {
1180 			musb_h_ep0_flush_fifo(hw_ep);
1181 		}
1182 
1183 		musb_writeb(epio, MUSB_NAKLIMIT0, 0);
1184 
1185 		/* clear it */
1186 		musb_writew(epio, MUSB_CSR0, 0);
1187 	}
1188 
1189 	if (unlikely(!urb)) {
1190 		/* stop endpoint since we have no place for its data, this
1191 		 * SHOULD NEVER HAPPEN! */
1192 		ERR("no URB for end 0\n");
1193 
1194 		musb_h_ep0_flush_fifo(hw_ep);
1195 		goto done;
1196 	}
1197 
1198 	if (!complete) {
1199 		/* call common logic and prepare response */
1200 		if (musb_h_ep0_continue(musb, len, urb)) {
1201 			/* more packets required */
1202 			csr = (MUSB_EP0_IN == musb->ep0_stage)
1203 				?  MUSB_CSR0_H_REQPKT : MUSB_CSR0_TXPKTRDY;
1204 		} else {
1205 			/* data transfer complete; perform status phase */
1206 			if (usb_pipeout(urb->pipe)
1207 					|| !urb->transfer_buffer_length)
1208 				csr = MUSB_CSR0_H_STATUSPKT
1209 					| MUSB_CSR0_H_REQPKT;
1210 			else
1211 				csr = MUSB_CSR0_H_STATUSPKT
1212 					| MUSB_CSR0_TXPKTRDY;
1213 
1214 			/* disable ping token in status phase */
1215 			csr |= MUSB_CSR0_H_DIS_PING;
1216 
1217 			/* flag status stage */
1218 			musb->ep0_stage = MUSB_EP0_STATUS;
1219 
1220 			musb_dbg(musb, "ep0 STATUS, csr %04x", csr);
1221 
1222 		}
1223 		musb_writew(epio, MUSB_CSR0, csr);
1224 		retval = IRQ_HANDLED;
1225 	} else
1226 		musb->ep0_stage = MUSB_EP0_IDLE;
1227 
1228 	/* call completion handler if done */
1229 	if (complete)
1230 		musb_advance_schedule(musb, urb, hw_ep, 1);
1231 done:
1232 	return retval;
1233 }
1234 
1235 
1236 #ifdef CONFIG_USB_INVENTRA_DMA
1237 
1238 /* Host side TX (OUT) using Mentor DMA works as follows:
1239 	submit_urb ->
1240 		- if queue was empty, Program Endpoint
1241 		- ... which starts DMA to fifo in mode 1 or 0
1242 
1243 	DMA Isr (transfer complete) -> TxAvail()
1244 		- Stop DMA (~DmaEnab)	(<--- Alert ... currently happens
1245 					only in musb_cleanup_urb)
1246 		- TxPktRdy has to be set in mode 0 or for
1247 			short packets in mode 1.
1248 */
1249 
1250 #endif
1251 
1252 /* Service a Tx-Available or dma completion irq for the endpoint */
musb_host_tx(struct musb * musb,u8 epnum)1253 void musb_host_tx(struct musb *musb, u8 epnum)
1254 {
1255 	int			pipe;
1256 	bool			done = false;
1257 	u16			tx_csr;
1258 	size_t			length = 0;
1259 	size_t			offset = 0;
1260 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1261 	void __iomem		*epio = hw_ep->regs;
1262 	struct musb_qh		*qh = hw_ep->out_qh;
1263 	struct urb		*urb = next_urb(qh);
1264 	u32			status = 0;
1265 	void __iomem		*mbase = musb->mregs;
1266 	struct dma_channel	*dma;
1267 	bool			transfer_pending = false;
1268 
1269 	musb_ep_select(mbase, epnum);
1270 	tx_csr = musb_readw(epio, MUSB_TXCSR);
1271 
1272 	/* with CPPI, DMA sometimes triggers "extra" irqs */
1273 	if (!urb) {
1274 		musb_dbg(musb, "extra TX%d ready, csr %04x", epnum, tx_csr);
1275 		return;
1276 	}
1277 
1278 	pipe = urb->pipe;
1279 	dma = is_dma_capable() ? hw_ep->tx_channel : NULL;
1280 	trace_musb_urb_tx(musb, urb);
1281 	musb_dbg(musb, "OUT/TX%d end, csr %04x%s", epnum, tx_csr,
1282 			dma ? ", dma" : "");
1283 
1284 	/* check for errors */
1285 	if (tx_csr & MUSB_TXCSR_H_RXSTALL) {
1286 		/* dma was disabled, fifo flushed */
1287 		musb_dbg(musb, "TX end %d stall", epnum);
1288 
1289 		/* stall; record URB status */
1290 		status = -EPIPE;
1291 
1292 	} else if (tx_csr & MUSB_TXCSR_H_ERROR) {
1293 		/* (NON-ISO) dma was disabled, fifo flushed */
1294 		musb_dbg(musb, "TX 3strikes on ep=%d", epnum);
1295 
1296 		status = -ETIMEDOUT;
1297 
1298 	} else if (tx_csr & MUSB_TXCSR_H_NAKTIMEOUT) {
1299 		if (USB_ENDPOINT_XFER_BULK == qh->type && qh->mux == 1
1300 				&& !list_is_singular(&musb->out_bulk)) {
1301 			musb_dbg(musb, "NAK timeout on TX%d ep", epnum);
1302 			musb_bulk_nak_timeout(musb, hw_ep, 0);
1303 		} else {
1304 			musb_dbg(musb, "TX ep%d device not responding", epnum);
1305 			/* NOTE:  this code path would be a good place to PAUSE a
1306 			 * transfer, if there's some other (nonperiodic) tx urb
1307 			 * that could use this fifo.  (dma complicates it...)
1308 			 * That's already done for bulk RX transfers.
1309 			 *
1310 			 * if (bulk && qh->ring.next != &musb->out_bulk), then
1311 			 * we have a candidate... NAKing is *NOT* an error
1312 			 */
1313 			musb_ep_select(mbase, epnum);
1314 			musb_writew(epio, MUSB_TXCSR,
1315 					MUSB_TXCSR_H_WZC_BITS
1316 					| MUSB_TXCSR_TXPKTRDY);
1317 		}
1318 			return;
1319 	}
1320 
1321 done:
1322 	if (status) {
1323 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1324 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1325 			musb->dma_controller->channel_abort(dma);
1326 		}
1327 
1328 		/* do the proper sequence to abort the transfer in the
1329 		 * usb core; the dma engine should already be stopped.
1330 		 */
1331 		musb_h_tx_flush_fifo(hw_ep);
1332 		tx_csr &= ~(MUSB_TXCSR_AUTOSET
1333 				| MUSB_TXCSR_DMAENAB
1334 				| MUSB_TXCSR_H_ERROR
1335 				| MUSB_TXCSR_H_RXSTALL
1336 				| MUSB_TXCSR_H_NAKTIMEOUT
1337 				);
1338 
1339 		musb_ep_select(mbase, epnum);
1340 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1341 		/* REVISIT may need to clear FLUSHFIFO ... */
1342 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1343 		musb_writeb(epio, MUSB_TXINTERVAL, 0);
1344 
1345 		done = true;
1346 	}
1347 
1348 	/* second cppi case */
1349 	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1350 		musb_dbg(musb, "extra TX%d ready, csr %04x", epnum, tx_csr);
1351 		return;
1352 	}
1353 
1354 	if (is_dma_capable() && dma && !status) {
1355 		/*
1356 		 * DMA has completed.  But if we're using DMA mode 1 (multi
1357 		 * packet DMA), we need a terminal TXPKTRDY interrupt before
1358 		 * we can consider this transfer completed, lest we trash
1359 		 * its last packet when writing the next URB's data.  So we
1360 		 * switch back to mode 0 to get that interrupt; we'll come
1361 		 * back here once it happens.
1362 		 */
1363 		if (tx_csr & MUSB_TXCSR_DMAMODE) {
1364 			/*
1365 			 * We shouldn't clear DMAMODE with DMAENAB set; so
1366 			 * clear them in a safe order.  That should be OK
1367 			 * once TXPKTRDY has been set (and I've never seen
1368 			 * it being 0 at this moment -- DMA interrupt latency
1369 			 * is significant) but if it hasn't been then we have
1370 			 * no choice but to stop being polite and ignore the
1371 			 * programmer's guide... :-)
1372 			 *
1373 			 * Note that we must write TXCSR with TXPKTRDY cleared
1374 			 * in order not to re-trigger the packet send (this bit
1375 			 * can't be cleared by CPU), and there's another caveat:
1376 			 * TXPKTRDY may be set shortly and then cleared in the
1377 			 * double-buffered FIFO mode, so we do an extra TXCSR
1378 			 * read for debouncing...
1379 			 */
1380 			tx_csr &= musb_readw(epio, MUSB_TXCSR);
1381 			if (tx_csr & MUSB_TXCSR_TXPKTRDY) {
1382 				tx_csr &= ~(MUSB_TXCSR_DMAENAB |
1383 					    MUSB_TXCSR_TXPKTRDY);
1384 				musb_writew(epio, MUSB_TXCSR,
1385 					    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1386 			}
1387 			tx_csr &= ~(MUSB_TXCSR_DMAMODE |
1388 				    MUSB_TXCSR_TXPKTRDY);
1389 			musb_writew(epio, MUSB_TXCSR,
1390 				    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1391 
1392 			/*
1393 			 * There is no guarantee that we'll get an interrupt
1394 			 * after clearing DMAMODE as we might have done this
1395 			 * too late (after TXPKTRDY was cleared by controller).
1396 			 * Re-read TXCSR as we have spoiled its previous value.
1397 			 */
1398 			tx_csr = musb_readw(epio, MUSB_TXCSR);
1399 		}
1400 
1401 		/*
1402 		 * We may get here from a DMA completion or TXPKTRDY interrupt.
1403 		 * In any case, we must check the FIFO status here and bail out
1404 		 * only if the FIFO still has data -- that should prevent the
1405 		 * "missed" TXPKTRDY interrupts and deal with double-buffered
1406 		 * FIFO mode too...
1407 		 */
1408 		if (tx_csr & (MUSB_TXCSR_FIFONOTEMPTY | MUSB_TXCSR_TXPKTRDY)) {
1409 			musb_dbg(musb,
1410 				"DMA complete but FIFO not empty, CSR %04x",
1411 				tx_csr);
1412 			return;
1413 		}
1414 	}
1415 
1416 	if (!status || dma || usb_pipeisoc(pipe)) {
1417 		if (dma)
1418 			length = dma->actual_len;
1419 		else
1420 			length = qh->segsize;
1421 		qh->offset += length;
1422 
1423 		if (usb_pipeisoc(pipe)) {
1424 			struct usb_iso_packet_descriptor	*d;
1425 
1426 			d = urb->iso_frame_desc + qh->iso_idx;
1427 			d->actual_length = length;
1428 			d->status = status;
1429 			if (++qh->iso_idx >= urb->number_of_packets) {
1430 				done = true;
1431 			} else {
1432 				d++;
1433 				offset = d->offset;
1434 				length = d->length;
1435 			}
1436 		} else if (dma && urb->transfer_buffer_length == qh->offset) {
1437 			done = true;
1438 		} else {
1439 			/* see if we need to send more data, or ZLP */
1440 			if (qh->segsize < qh->maxpacket)
1441 				done = true;
1442 			else if (qh->offset == urb->transfer_buffer_length
1443 					&& !(urb->transfer_flags
1444 						& URB_ZERO_PACKET))
1445 				done = true;
1446 			if (!done) {
1447 				offset = qh->offset;
1448 				length = urb->transfer_buffer_length - offset;
1449 				transfer_pending = true;
1450 			}
1451 		}
1452 	}
1453 
1454 	/* urb->status != -EINPROGRESS means request has been faulted,
1455 	 * so we must abort this transfer after cleanup
1456 	 */
1457 	if (urb->status != -EINPROGRESS) {
1458 		done = true;
1459 		if (status == 0)
1460 			status = urb->status;
1461 	}
1462 
1463 	if (done) {
1464 		/* set status */
1465 		urb->status = status;
1466 		urb->actual_length = qh->offset;
1467 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_OUT);
1468 		return;
1469 	} else if ((usb_pipeisoc(pipe) || transfer_pending) && dma) {
1470 		if (musb_tx_dma_program(musb->dma_controller, hw_ep, qh, urb,
1471 				offset, length)) {
1472 			if (is_cppi_enabled(musb) || tusb_dma_omap(musb))
1473 				musb_h_tx_dma_start(hw_ep);
1474 			return;
1475 		}
1476 	} else	if (tx_csr & MUSB_TXCSR_DMAENAB) {
1477 		musb_dbg(musb, "not complete, but DMA enabled?");
1478 		return;
1479 	}
1480 
1481 	/*
1482 	 * PIO: start next packet in this URB.
1483 	 *
1484 	 * REVISIT: some docs say that when hw_ep->tx_double_buffered,
1485 	 * (and presumably, FIFO is not half-full) we should write *two*
1486 	 * packets before updating TXCSR; other docs disagree...
1487 	 */
1488 	if (length > qh->maxpacket)
1489 		length = qh->maxpacket;
1490 	/* Unmap the buffer so that CPU can use it */
1491 	usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1492 
1493 	/*
1494 	 * We need to map sg if the transfer_buffer is
1495 	 * NULL.
1496 	 */
1497 	if (!urb->transfer_buffer) {
1498 		/* sg_miter_start is already done in musb_ep_program */
1499 		if (!sg_miter_next(&qh->sg_miter)) {
1500 			dev_err(musb->controller, "error: sg list empty\n");
1501 			sg_miter_stop(&qh->sg_miter);
1502 			status = -EINVAL;
1503 			goto done;
1504 		}
1505 		length = min_t(u32, length, qh->sg_miter.length);
1506 		musb_write_fifo(hw_ep, length, qh->sg_miter.addr);
1507 		qh->sg_miter.consumed = length;
1508 		sg_miter_stop(&qh->sg_miter);
1509 	} else {
1510 		musb_write_fifo(hw_ep, length, urb->transfer_buffer + offset);
1511 	}
1512 
1513 	qh->segsize = length;
1514 
1515 	musb_ep_select(mbase, epnum);
1516 	musb_writew(epio, MUSB_TXCSR,
1517 			MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
1518 }
1519 
1520 #ifdef CONFIG_USB_TI_CPPI41_DMA
1521 /* Seems to set up ISO for cppi41 and not advance len. See commit c57c41d */
musb_rx_dma_iso_cppi41(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,size_t len)1522 static int musb_rx_dma_iso_cppi41(struct dma_controller *dma,
1523 				  struct musb_hw_ep *hw_ep,
1524 				  struct musb_qh *qh,
1525 				  struct urb *urb,
1526 				  size_t len)
1527 {
1528 	struct dma_channel *channel = hw_ep->rx_channel;
1529 	void __iomem *epio = hw_ep->regs;
1530 	dma_addr_t *buf;
1531 	u32 length;
1532 	u16 val;
1533 
1534 	buf = (void *)urb->iso_frame_desc[qh->iso_idx].offset +
1535 		(u32)urb->transfer_dma;
1536 
1537 	length = urb->iso_frame_desc[qh->iso_idx].length;
1538 
1539 	val = musb_readw(epio, MUSB_RXCSR);
1540 	val |= MUSB_RXCSR_DMAENAB;
1541 	musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1542 
1543 	return dma->channel_program(channel, qh->maxpacket, 0,
1544 				   (u32)buf, length);
1545 }
1546 #else
musb_rx_dma_iso_cppi41(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,size_t len)1547 static inline int musb_rx_dma_iso_cppi41(struct dma_controller *dma,
1548 					 struct musb_hw_ep *hw_ep,
1549 					 struct musb_qh *qh,
1550 					 struct urb *urb,
1551 					 size_t len)
1552 {
1553 	return false;
1554 }
1555 #endif
1556 
1557 #if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA) || \
1558 	defined(CONFIG_USB_TI_CPPI41_DMA)
1559 /* Host side RX (IN) using Mentor DMA works as follows:
1560 	submit_urb ->
1561 		- if queue was empty, ProgramEndpoint
1562 		- first IN token is sent out (by setting ReqPkt)
1563 	LinuxIsr -> RxReady()
1564 	/\	=> first packet is received
1565 	|	- Set in mode 0 (DmaEnab, ~ReqPkt)
1566 	|		-> DMA Isr (transfer complete) -> RxReady()
1567 	|		    - Ack receive (~RxPktRdy), turn off DMA (~DmaEnab)
1568 	|		    - if urb not complete, send next IN token (ReqPkt)
1569 	|			   |		else complete urb.
1570 	|			   |
1571 	---------------------------
1572  *
1573  * Nuances of mode 1:
1574  *	For short packets, no ack (+RxPktRdy) is sent automatically
1575  *	(even if AutoClear is ON)
1576  *	For full packets, ack (~RxPktRdy) and next IN token (+ReqPkt) is sent
1577  *	automatically => major problem, as collecting the next packet becomes
1578  *	difficult. Hence mode 1 is not used.
1579  *
1580  * REVISIT
1581  *	All we care about at this driver level is that
1582  *       (a) all URBs terminate with REQPKT cleared and fifo(s) empty;
1583  *       (b) termination conditions are: short RX, or buffer full;
1584  *       (c) fault modes include
1585  *           - iff URB_SHORT_NOT_OK, short RX status is -EREMOTEIO.
1586  *             (and that endpoint's dma queue stops immediately)
1587  *           - overflow (full, PLUS more bytes in the terminal packet)
1588  *
1589  *	So for example, usb-storage sets URB_SHORT_NOT_OK, and would
1590  *	thus be a great candidate for using mode 1 ... for all but the
1591  *	last packet of one URB's transfer.
1592  */
musb_rx_dma_inventra_cppi41(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,size_t len)1593 static int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
1594 				       struct musb_hw_ep *hw_ep,
1595 				       struct musb_qh *qh,
1596 				       struct urb *urb,
1597 				       size_t len)
1598 {
1599 	struct dma_channel *channel = hw_ep->rx_channel;
1600 	void __iomem *epio = hw_ep->regs;
1601 	u16 val;
1602 	int pipe;
1603 	bool done;
1604 
1605 	pipe = urb->pipe;
1606 
1607 	if (usb_pipeisoc(pipe)) {
1608 		struct usb_iso_packet_descriptor *d;
1609 
1610 		d = urb->iso_frame_desc + qh->iso_idx;
1611 		d->actual_length = len;
1612 
1613 		/* even if there was an error, we did the dma
1614 		 * for iso_frame_desc->length
1615 		 */
1616 		if (d->status != -EILSEQ && d->status != -EOVERFLOW)
1617 			d->status = 0;
1618 
1619 		if (++qh->iso_idx >= urb->number_of_packets) {
1620 			done = true;
1621 		} else {
1622 			/* REVISIT: Why ignore return value here? */
1623 			if (musb_dma_cppi41(hw_ep->musb))
1624 				done = musb_rx_dma_iso_cppi41(dma, hw_ep, qh,
1625 							      urb, len);
1626 			done = false;
1627 		}
1628 
1629 	} else  {
1630 		/* done if urb buffer is full or short packet is recd */
1631 		done = (urb->actual_length + len >=
1632 			urb->transfer_buffer_length
1633 			|| channel->actual_len < qh->maxpacket
1634 			|| channel->rx_packet_done);
1635 	}
1636 
1637 	/* send IN token for next packet, without AUTOREQ */
1638 	if (!done) {
1639 		val = musb_readw(epio, MUSB_RXCSR);
1640 		val |= MUSB_RXCSR_H_REQPKT;
1641 		musb_writew(epio, MUSB_RXCSR, MUSB_RXCSR_H_WZC_BITS | val);
1642 	}
1643 
1644 	return done;
1645 }
1646 
1647 /* Disadvantage of using mode 1:
1648  *	It's basically usable only for mass storage class; essentially all
1649  *	other protocols also terminate transfers on short packets.
1650  *
1651  * Details:
1652  *	An extra IN token is sent at the end of the transfer (due to AUTOREQ)
1653  *	If you try to use mode 1 for (transfer_buffer_length - 512), and try
1654  *	to use the extra IN token to grab the last packet using mode 0, then
1655  *	the problem is that you cannot be sure when the device will send the
1656  *	last packet and RxPktRdy set. Sometimes the packet is recd too soon
1657  *	such that it gets lost when RxCSR is re-set at the end of the mode 1
1658  *	transfer, while sometimes it is recd just a little late so that if you
1659  *	try to configure for mode 0 soon after the mode 1 transfer is
1660  *	completed, you will find rxcount 0. Okay, so you might think why not
1661  *	wait for an interrupt when the pkt is recd. Well, you won't get any!
1662  */
musb_rx_dma_in_inventra_cppi41(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,size_t len,u8 iso_err)1663 static int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
1664 					  struct musb_hw_ep *hw_ep,
1665 					  struct musb_qh *qh,
1666 					  struct urb *urb,
1667 					  size_t len,
1668 					  u8 iso_err)
1669 {
1670 	struct musb *musb = hw_ep->musb;
1671 	void __iomem *epio = hw_ep->regs;
1672 	struct dma_channel *channel = hw_ep->rx_channel;
1673 	u16 rx_count, val;
1674 	int length, pipe, done;
1675 	dma_addr_t buf;
1676 
1677 	rx_count = musb_readw(epio, MUSB_RXCOUNT);
1678 	pipe = urb->pipe;
1679 
1680 	if (usb_pipeisoc(pipe)) {
1681 		int d_status = 0;
1682 		struct usb_iso_packet_descriptor *d;
1683 
1684 		d = urb->iso_frame_desc + qh->iso_idx;
1685 
1686 		if (iso_err) {
1687 			d_status = -EILSEQ;
1688 			urb->error_count++;
1689 		}
1690 		if (rx_count > d->length) {
1691 			if (d_status == 0) {
1692 				d_status = -EOVERFLOW;
1693 				urb->error_count++;
1694 			}
1695 			musb_dbg(musb, "** OVERFLOW %d into %d",
1696 				rx_count, d->length);
1697 
1698 			length = d->length;
1699 		} else
1700 			length = rx_count;
1701 		d->status = d_status;
1702 		buf = urb->transfer_dma + d->offset;
1703 	} else {
1704 		length = rx_count;
1705 		buf = urb->transfer_dma + urb->actual_length;
1706 	}
1707 
1708 	channel->desired_mode = 0;
1709 #ifdef USE_MODE1
1710 	/* because of the issue below, mode 1 will
1711 	 * only rarely behave with correct semantics.
1712 	 */
1713 	if ((urb->transfer_flags & URB_SHORT_NOT_OK)
1714 	    && (urb->transfer_buffer_length - urb->actual_length)
1715 	    > qh->maxpacket)
1716 		channel->desired_mode = 1;
1717 	if (rx_count < hw_ep->max_packet_sz_rx) {
1718 		length = rx_count;
1719 		channel->desired_mode = 0;
1720 	} else {
1721 		length = urb->transfer_buffer_length;
1722 	}
1723 #endif
1724 
1725 	/* See comments above on disadvantages of using mode 1 */
1726 	val = musb_readw(epio, MUSB_RXCSR);
1727 	val &= ~MUSB_RXCSR_H_REQPKT;
1728 
1729 	if (channel->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, MUSB_RXCSR_H_WZC_BITS | val);
1740 
1741 	/* REVISIT if when actual_length != 0,
1742 	 * transfer_buffer_length needs to be
1743 	 * adjusted first...
1744 	 */
1745 	done = dma->channel_program(channel, qh->maxpacket,
1746 				   channel->desired_mode,
1747 				   buf, length);
1748 
1749 	if (!done) {
1750 		dma->channel_release(channel);
1751 		hw_ep->rx_channel = NULL;
1752 		channel = NULL;
1753 		val = musb_readw(epio, MUSB_RXCSR);
1754 		val &= ~(MUSB_RXCSR_DMAENAB
1755 			 | MUSB_RXCSR_H_AUTOREQ
1756 			 | MUSB_RXCSR_AUTOCLEAR);
1757 		musb_writew(epio, MUSB_RXCSR, val);
1758 	}
1759 
1760 	return done;
1761 }
1762 #else
musb_rx_dma_inventra_cppi41(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,size_t len)1763 static inline int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
1764 					      struct musb_hw_ep *hw_ep,
1765 					      struct musb_qh *qh,
1766 					      struct urb *urb,
1767 					      size_t len)
1768 {
1769 	return false;
1770 }
1771 
musb_rx_dma_in_inventra_cppi41(struct dma_controller * dma,struct musb_hw_ep * hw_ep,struct musb_qh * qh,struct urb * urb,size_t len,u8 iso_err)1772 static inline int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
1773 						 struct musb_hw_ep *hw_ep,
1774 						 struct musb_qh *qh,
1775 						 struct urb *urb,
1776 						 size_t len,
1777 						 u8 iso_err)
1778 {
1779 	return false;
1780 }
1781 #endif
1782 
1783 /*
1784  * Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
1785  * and high-bandwidth IN transfer cases.
1786  */
musb_host_rx(struct musb * musb,u8 epnum)1787 void musb_host_rx(struct musb *musb, u8 epnum)
1788 {
1789 	struct urb		*urb;
1790 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1791 	struct dma_controller	*c = musb->dma_controller;
1792 	void __iomem		*epio = hw_ep->regs;
1793 	struct musb_qh		*qh = hw_ep->in_qh;
1794 	size_t			xfer_len;
1795 	void __iomem		*mbase = musb->mregs;
1796 	int			pipe;
1797 	u16			rx_csr, val;
1798 	bool			iso_err = false;
1799 	bool			done = false;
1800 	u32			status;
1801 	struct dma_channel	*dma;
1802 	unsigned int sg_flags = SG_MITER_ATOMIC | SG_MITER_TO_SG;
1803 
1804 	musb_ep_select(mbase, epnum);
1805 
1806 	urb = next_urb(qh);
1807 	dma = is_dma_capable() ? hw_ep->rx_channel : NULL;
1808 	status = 0;
1809 	xfer_len = 0;
1810 
1811 	rx_csr = musb_readw(epio, MUSB_RXCSR);
1812 	val = rx_csr;
1813 
1814 	if (unlikely(!urb)) {
1815 		/* REVISIT -- THIS SHOULD NEVER HAPPEN ... but, at least
1816 		 * usbtest #11 (unlinks) triggers it regularly, sometimes
1817 		 * with fifo full.  (Only with DMA??)
1818 		 */
1819 		musb_dbg(musb, "BOGUS RX%d ready, csr %04x, count %d",
1820 			epnum, val, musb_readw(epio, MUSB_RXCOUNT));
1821 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1822 		return;
1823 	}
1824 
1825 	pipe = urb->pipe;
1826 
1827 	trace_musb_urb_rx(musb, urb);
1828 
1829 	/* check for errors, concurrent stall & unlink is not really
1830 	 * handled yet! */
1831 	if (rx_csr & MUSB_RXCSR_H_RXSTALL) {
1832 		musb_dbg(musb, "RX end %d STALL", epnum);
1833 
1834 		/* stall; record URB status */
1835 		status = -EPIPE;
1836 
1837 	} else if (rx_csr & MUSB_RXCSR_H_ERROR) {
1838 		musb_dbg(musb, "end %d RX proto error", epnum);
1839 
1840 		status = -EPROTO;
1841 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1842 
1843 		rx_csr &= ~MUSB_RXCSR_H_ERROR;
1844 		musb_writew(epio, MUSB_RXCSR, rx_csr);
1845 
1846 	} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
1847 
1848 		if (USB_ENDPOINT_XFER_ISOC != qh->type) {
1849 			musb_dbg(musb, "RX end %d NAK timeout", epnum);
1850 
1851 			/* NOTE: NAKing is *NOT* an error, so we want to
1852 			 * continue.  Except ... if there's a request for
1853 			 * another QH, use that instead of starving it.
1854 			 *
1855 			 * Devices like Ethernet and serial adapters keep
1856 			 * reads posted at all times, which will starve
1857 			 * other devices without this logic.
1858 			 */
1859 			if (usb_pipebulk(urb->pipe)
1860 					&& qh->mux == 1
1861 					&& !list_is_singular(&musb->in_bulk)) {
1862 				musb_bulk_nak_timeout(musb, hw_ep, 1);
1863 				return;
1864 			}
1865 			musb_ep_select(mbase, epnum);
1866 			rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1867 			rx_csr &= ~MUSB_RXCSR_DATAERROR;
1868 			musb_writew(epio, MUSB_RXCSR, rx_csr);
1869 
1870 			goto finish;
1871 		} else {
1872 			musb_dbg(musb, "RX end %d ISO data error", epnum);
1873 			/* packet error reported later */
1874 			iso_err = true;
1875 		}
1876 	} else if (rx_csr & MUSB_RXCSR_INCOMPRX) {
1877 		musb_dbg(musb, "end %d high bandwidth incomplete ISO packet RX",
1878 				epnum);
1879 		status = -EPROTO;
1880 	}
1881 
1882 	/* faults abort the transfer */
1883 	if (status) {
1884 		/* clean up dma and collect transfer count */
1885 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1886 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1887 			musb->dma_controller->channel_abort(dma);
1888 			xfer_len = dma->actual_len;
1889 		}
1890 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1891 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1892 		done = true;
1893 		goto finish;
1894 	}
1895 
1896 	if (unlikely(dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY)) {
1897 		/* SHOULD NEVER HAPPEN ... but at least DaVinci has done it */
1898 		ERR("RX%d dma busy, csr %04x\n", epnum, rx_csr);
1899 		goto finish;
1900 	}
1901 
1902 	/* thorough shutdown for now ... given more precise fault handling
1903 	 * and better queueing support, we might keep a DMA pipeline going
1904 	 * while processing this irq for earlier completions.
1905 	 */
1906 
1907 	/* FIXME this is _way_ too much in-line logic for Mentor DMA */
1908 	if (!musb_dma_inventra(musb) && !musb_dma_ux500(musb) &&
1909 	    (rx_csr & MUSB_RXCSR_H_REQPKT)) {
1910 		/* REVISIT this happened for a while on some short reads...
1911 		 * the cleanup still needs investigation... looks bad...
1912 		 * and also duplicates dma cleanup code above ... plus,
1913 		 * shouldn't this be the "half full" double buffer case?
1914 		 */
1915 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1916 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1917 			musb->dma_controller->channel_abort(dma);
1918 			xfer_len = dma->actual_len;
1919 			done = true;
1920 		}
1921 
1922 		musb_dbg(musb, "RXCSR%d %04x, reqpkt, len %zu%s", epnum, rx_csr,
1923 				xfer_len, dma ? ", dma" : "");
1924 		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
1925 
1926 		musb_ep_select(mbase, epnum);
1927 		musb_writew(epio, MUSB_RXCSR,
1928 				MUSB_RXCSR_H_WZC_BITS | rx_csr);
1929 	}
1930 
1931 	if (dma && (rx_csr & MUSB_RXCSR_DMAENAB)) {
1932 		xfer_len = dma->actual_len;
1933 
1934 		val &= ~(MUSB_RXCSR_DMAENAB
1935 			| MUSB_RXCSR_H_AUTOREQ
1936 			| MUSB_RXCSR_AUTOCLEAR
1937 			| MUSB_RXCSR_RXPKTRDY);
1938 		musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1939 
1940 		if (musb_dma_inventra(musb) || musb_dma_ux500(musb) ||
1941 		    musb_dma_cppi41(musb)) {
1942 			    done = musb_rx_dma_inventra_cppi41(c, hw_ep, qh, urb, xfer_len);
1943 			    musb_dbg(hw_ep->musb,
1944 				    "ep %d dma %s, rxcsr %04x, rxcount %d",
1945 				    epnum, done ? "off" : "reset",
1946 				    musb_readw(epio, MUSB_RXCSR),
1947 				    musb_readw(epio, MUSB_RXCOUNT));
1948 		} else {
1949 			done = true;
1950 		}
1951 
1952 	} else if (urb->status == -EINPROGRESS) {
1953 		/* if no errors, be sure a packet is ready for unloading */
1954 		if (unlikely(!(rx_csr & MUSB_RXCSR_RXPKTRDY))) {
1955 			status = -EPROTO;
1956 			ERR("Rx interrupt with no errors or packet!\n");
1957 
1958 			/* FIXME this is another "SHOULD NEVER HAPPEN" */
1959 
1960 /* SCRUB (RX) */
1961 			/* do the proper sequence to abort the transfer */
1962 			musb_ep_select(mbase, epnum);
1963 			val &= ~MUSB_RXCSR_H_REQPKT;
1964 			musb_writew(epio, MUSB_RXCSR, val);
1965 			goto finish;
1966 		}
1967 
1968 		/* we are expecting IN packets */
1969 		if ((musb_dma_inventra(musb) || musb_dma_ux500(musb) ||
1970 		    musb_dma_cppi41(musb)) && dma) {
1971 			musb_dbg(hw_ep->musb,
1972 				"RX%d count %d, buffer 0x%llx len %d/%d",
1973 				epnum, musb_readw(epio, MUSB_RXCOUNT),
1974 				(unsigned long long) urb->transfer_dma
1975 				+ urb->actual_length,
1976 				qh->offset,
1977 				urb->transfer_buffer_length);
1978 
1979 			if (musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh, urb,
1980 							   xfer_len, iso_err))
1981 				goto finish;
1982 			else
1983 				dev_err(musb->controller, "error: rx_dma failed\n");
1984 		}
1985 
1986 		if (!dma) {
1987 			unsigned int received_len;
1988 
1989 			/* Unmap the buffer so that CPU can use it */
1990 			usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1991 
1992 			/*
1993 			 * We need to map sg if the transfer_buffer is
1994 			 * NULL.
1995 			 */
1996 			if (!urb->transfer_buffer) {
1997 				qh->use_sg = true;
1998 				sg_miter_start(&qh->sg_miter, urb->sg, 1,
1999 						sg_flags);
2000 			}
2001 
2002 			if (qh->use_sg) {
2003 				if (!sg_miter_next(&qh->sg_miter)) {
2004 					dev_err(musb->controller, "error: sg list empty\n");
2005 					sg_miter_stop(&qh->sg_miter);
2006 					status = -EINVAL;
2007 					done = true;
2008 					goto finish;
2009 				}
2010 				urb->transfer_buffer = qh->sg_miter.addr;
2011 				received_len = urb->actual_length;
2012 				qh->offset = 0x0;
2013 				done = musb_host_packet_rx(musb, urb, epnum,
2014 						iso_err);
2015 				/* Calculate the number of bytes received */
2016 				received_len = urb->actual_length -
2017 					received_len;
2018 				qh->sg_miter.consumed = received_len;
2019 				sg_miter_stop(&qh->sg_miter);
2020 			} else {
2021 				done = musb_host_packet_rx(musb, urb,
2022 						epnum, iso_err);
2023 			}
2024 			musb_dbg(musb, "read %spacket", done ? "last " : "");
2025 		}
2026 	}
2027 
2028 finish:
2029 	urb->actual_length += xfer_len;
2030 	qh->offset += xfer_len;
2031 	if (done) {
2032 		if (qh->use_sg) {
2033 			qh->use_sg = false;
2034 			urb->transfer_buffer = NULL;
2035 		}
2036 
2037 		if (urb->status == -EINPROGRESS)
2038 			urb->status = status;
2039 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_IN);
2040 	}
2041 }
2042 
2043 /* schedule nodes correspond to peripheral endpoints, like an OHCI QH.
2044  * the software schedule associates multiple such nodes with a given
2045  * host side hardware endpoint + direction; scheduling may activate
2046  * that hardware endpoint.
2047  */
musb_schedule(struct musb * musb,struct musb_qh * qh,int is_in)2048 static int musb_schedule(
2049 	struct musb		*musb,
2050 	struct musb_qh		*qh,
2051 	int			is_in)
2052 {
2053 	int			idle = 0;
2054 	int			best_diff;
2055 	int			best_end, epnum;
2056 	struct musb_hw_ep	*hw_ep = NULL;
2057 	struct list_head	*head = NULL;
2058 	u8			toggle;
2059 	u8			txtype;
2060 	struct urb		*urb = next_urb(qh);
2061 
2062 	/* use fixed hardware for control and bulk */
2063 	if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
2064 		head = &musb->control;
2065 		hw_ep = musb->control_ep;
2066 		goto success;
2067 	}
2068 
2069 	/* else, periodic transfers get muxed to other endpoints */
2070 
2071 	/*
2072 	 * We know this qh hasn't been scheduled, so all we need to do
2073 	 * is choose which hardware endpoint to put it on ...
2074 	 *
2075 	 * REVISIT what we really want here is a regular schedule tree
2076 	 * like e.g. OHCI uses.
2077 	 */
2078 	best_diff = 4096;
2079 	best_end = -1;
2080 
2081 	for (epnum = 1, hw_ep = musb->endpoints + 1;
2082 			epnum < musb->nr_endpoints;
2083 			epnum++, hw_ep++) {
2084 		int	diff;
2085 
2086 		if (musb_ep_get_qh(hw_ep, is_in) != NULL)
2087 			continue;
2088 
2089 		if (hw_ep == musb->bulk_ep)
2090 			continue;
2091 
2092 		if (is_in)
2093 			diff = hw_ep->max_packet_sz_rx;
2094 		else
2095 			diff = hw_ep->max_packet_sz_tx;
2096 		diff -= (qh->maxpacket * qh->hb_mult);
2097 
2098 		if (diff >= 0 && best_diff > diff) {
2099 
2100 			/*
2101 			 * Mentor controller has a bug in that if we schedule
2102 			 * a BULK Tx transfer on an endpoint that had earlier
2103 			 * handled ISOC then the BULK transfer has to start on
2104 			 * a zero toggle.  If the BULK transfer starts on a 1
2105 			 * toggle then this transfer will fail as the mentor
2106 			 * controller starts the Bulk transfer on a 0 toggle
2107 			 * irrespective of the programming of the toggle bits
2108 			 * in the TXCSR register.  Check for this condition
2109 			 * while allocating the EP for a Tx Bulk transfer.  If
2110 			 * so skip this EP.
2111 			 */
2112 			hw_ep = musb->endpoints + epnum;
2113 			toggle = usb_gettoggle(urb->dev, qh->epnum, !is_in);
2114 			txtype = (musb_readb(hw_ep->regs, MUSB_TXTYPE)
2115 					>> 4) & 0x3;
2116 			if (!is_in && (qh->type == USB_ENDPOINT_XFER_BULK) &&
2117 				toggle && (txtype == USB_ENDPOINT_XFER_ISOC))
2118 				continue;
2119 
2120 			best_diff = diff;
2121 			best_end = epnum;
2122 		}
2123 	}
2124 	/* use bulk reserved ep1 if no other ep is free */
2125 	if (best_end < 0 && qh->type == USB_ENDPOINT_XFER_BULK) {
2126 		hw_ep = musb->bulk_ep;
2127 		if (is_in)
2128 			head = &musb->in_bulk;
2129 		else
2130 			head = &musb->out_bulk;
2131 
2132 		/* Enable bulk RX/TX NAK timeout scheme when bulk requests are
2133 		 * multiplexed. This scheme does not work in high speed to full
2134 		 * speed scenario as NAK interrupts are not coming from a
2135 		 * full speed device connected to a high speed device.
2136 		 * NAK timeout interval is 8 (128 uframe or 16ms) for HS and
2137 		 * 4 (8 frame or 8ms) for FS device.
2138 		 */
2139 		if (qh->dev)
2140 			qh->intv_reg =
2141 				(USB_SPEED_HIGH == qh->dev->speed) ? 8 : 4;
2142 		goto success;
2143 	} else if (best_end < 0) {
2144 		dev_err(musb->controller,
2145 				"%s hwep alloc failed for %dx%d\n",
2146 				musb_ep_xfertype_string(qh->type),
2147 				qh->hb_mult, qh->maxpacket);
2148 		return -ENOSPC;
2149 	}
2150 
2151 	idle = 1;
2152 	qh->mux = 0;
2153 	hw_ep = musb->endpoints + best_end;
2154 	musb_dbg(musb, "qh %p periodic slot %d", qh, best_end);
2155 success:
2156 	if (head) {
2157 		idle = list_empty(head);
2158 		list_add_tail(&qh->ring, head);
2159 		qh->mux = 1;
2160 	}
2161 	qh->hw_ep = hw_ep;
2162 	qh->hep->hcpriv = qh;
2163 	if (idle)
2164 		musb_start_urb(musb, is_in, qh);
2165 	return 0;
2166 }
2167 
musb_urb_enqueue(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)2168 static int musb_urb_enqueue(
2169 	struct usb_hcd			*hcd,
2170 	struct urb			*urb,
2171 	gfp_t				mem_flags)
2172 {
2173 	unsigned long			flags;
2174 	struct musb			*musb = hcd_to_musb(hcd);
2175 	struct usb_host_endpoint	*hep = urb->ep;
2176 	struct musb_qh			*qh;
2177 	struct usb_endpoint_descriptor	*epd = &hep->desc;
2178 	int				ret;
2179 	unsigned			type_reg;
2180 	unsigned			interval;
2181 
2182 	/* host role must be active */
2183 	if (!is_host_active(musb) || !musb->is_active)
2184 		return -ENODEV;
2185 
2186 	trace_musb_urb_enq(musb, urb);
2187 
2188 	spin_lock_irqsave(&musb->lock, flags);
2189 	ret = usb_hcd_link_urb_to_ep(hcd, urb);
2190 	qh = ret ? NULL : hep->hcpriv;
2191 	if (qh)
2192 		urb->hcpriv = qh;
2193 	spin_unlock_irqrestore(&musb->lock, flags);
2194 
2195 	/* DMA mapping was already done, if needed, and this urb is on
2196 	 * hep->urb_list now ... so we're done, unless hep wasn't yet
2197 	 * scheduled onto a live qh.
2198 	 *
2199 	 * REVISIT best to keep hep->hcpriv valid until the endpoint gets
2200 	 * disabled, testing for empty qh->ring and avoiding qh setup costs
2201 	 * except for the first urb queued after a config change.
2202 	 */
2203 	if (qh || ret)
2204 		return ret;
2205 
2206 	/* Allocate and initialize qh, minimizing the work done each time
2207 	 * hw_ep gets reprogrammed, or with irqs blocked.  Then schedule it.
2208 	 *
2209 	 * REVISIT consider a dedicated qh kmem_cache, so it's harder
2210 	 * for bugs in other kernel code to break this driver...
2211 	 */
2212 	qh = kzalloc(sizeof *qh, mem_flags);
2213 	if (!qh) {
2214 		spin_lock_irqsave(&musb->lock, flags);
2215 		usb_hcd_unlink_urb_from_ep(hcd, urb);
2216 		spin_unlock_irqrestore(&musb->lock, flags);
2217 		return -ENOMEM;
2218 	}
2219 
2220 	qh->hep = hep;
2221 	qh->dev = urb->dev;
2222 	INIT_LIST_HEAD(&qh->ring);
2223 	qh->is_ready = 1;
2224 
2225 	qh->maxpacket = usb_endpoint_maxp(epd);
2226 	qh->type = usb_endpoint_type(epd);
2227 
2228 	/* Bits 11 & 12 of wMaxPacketSize encode high bandwidth multiplier.
2229 	 * Some musb cores don't support high bandwidth ISO transfers; and
2230 	 * we don't (yet!) support high bandwidth interrupt transfers.
2231 	 */
2232 	qh->hb_mult = usb_endpoint_maxp_mult(epd);
2233 	if (qh->hb_mult > 1) {
2234 		int ok = (qh->type == USB_ENDPOINT_XFER_ISOC);
2235 
2236 		if (ok)
2237 			ok = (usb_pipein(urb->pipe) && musb->hb_iso_rx)
2238 				|| (usb_pipeout(urb->pipe) && musb->hb_iso_tx);
2239 		if (!ok) {
2240 			dev_err(musb->controller,
2241 				"high bandwidth %s (%dx%d) not supported\n",
2242 				musb_ep_xfertype_string(qh->type),
2243 				qh->hb_mult, qh->maxpacket & 0x7ff);
2244 			ret = -EMSGSIZE;
2245 			goto done;
2246 		}
2247 		qh->maxpacket &= 0x7ff;
2248 	}
2249 
2250 	qh->epnum = usb_endpoint_num(epd);
2251 
2252 	/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
2253 	qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
2254 
2255 	/* precompute rxtype/txtype/type0 register */
2256 	type_reg = (qh->type << 4) | qh->epnum;
2257 	switch (urb->dev->speed) {
2258 	case USB_SPEED_LOW:
2259 		type_reg |= 0xc0;
2260 		break;
2261 	case USB_SPEED_FULL:
2262 		type_reg |= 0x80;
2263 		break;
2264 	default:
2265 		type_reg |= 0x40;
2266 	}
2267 	qh->type_reg = type_reg;
2268 
2269 	/* Precompute RXINTERVAL/TXINTERVAL register */
2270 	switch (qh->type) {
2271 	case USB_ENDPOINT_XFER_INT:
2272 		/*
2273 		 * Full/low speeds use the  linear encoding,
2274 		 * high speed uses the logarithmic encoding.
2275 		 */
2276 		if (urb->dev->speed <= USB_SPEED_FULL) {
2277 			interval = max_t(u8, epd->bInterval, 1);
2278 			break;
2279 		}
2280 		/* FALLTHROUGH */
2281 	case USB_ENDPOINT_XFER_ISOC:
2282 		/* ISO always uses logarithmic encoding */
2283 		interval = min_t(u8, epd->bInterval, 16);
2284 		break;
2285 	default:
2286 		/* REVISIT we actually want to use NAK limits, hinting to the
2287 		 * transfer scheduling logic to try some other qh, e.g. try
2288 		 * for 2 msec first:
2289 		 *
2290 		 * interval = (USB_SPEED_HIGH == urb->dev->speed) ? 16 : 2;
2291 		 *
2292 		 * The downside of disabling this is that transfer scheduling
2293 		 * gets VERY unfair for nonperiodic transfers; a misbehaving
2294 		 * peripheral could make that hurt.  That's perfectly normal
2295 		 * for reads from network or serial adapters ... so we have
2296 		 * partial NAKlimit support for bulk RX.
2297 		 *
2298 		 * The upside of disabling it is simpler transfer scheduling.
2299 		 */
2300 		interval = 0;
2301 	}
2302 	qh->intv_reg = interval;
2303 
2304 	/* precompute addressing for external hub/tt ports */
2305 	if (musb->is_multipoint) {
2306 		struct usb_device	*parent = urb->dev->parent;
2307 
2308 		if (parent != hcd->self.root_hub) {
2309 			qh->h_addr_reg = (u8) parent->devnum;
2310 
2311 			/* set up tt info if needed */
2312 			if (urb->dev->tt) {
2313 				qh->h_port_reg = (u8) urb->dev->ttport;
2314 				if (urb->dev->tt->hub)
2315 					qh->h_addr_reg =
2316 						(u8) urb->dev->tt->hub->devnum;
2317 				if (urb->dev->tt->multi)
2318 					qh->h_addr_reg |= 0x80;
2319 			}
2320 		}
2321 	}
2322 
2323 	/* invariant: hep->hcpriv is null OR the qh that's already scheduled.
2324 	 * until we get real dma queues (with an entry for each urb/buffer),
2325 	 * we only have work to do in the former case.
2326 	 */
2327 	spin_lock_irqsave(&musb->lock, flags);
2328 	if (hep->hcpriv || !next_urb(qh)) {
2329 		/* some concurrent activity submitted another urb to hep...
2330 		 * odd, rare, error prone, but legal.
2331 		 */
2332 		kfree(qh);
2333 		qh = NULL;
2334 		ret = 0;
2335 	} else
2336 		ret = musb_schedule(musb, qh,
2337 				epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK);
2338 
2339 	if (ret == 0) {
2340 		urb->hcpriv = qh;
2341 		/* FIXME set urb->start_frame for iso/intr, it's tested in
2342 		 * musb_start_urb(), but otherwise only konicawc cares ...
2343 		 */
2344 	}
2345 	spin_unlock_irqrestore(&musb->lock, flags);
2346 
2347 done:
2348 	if (ret != 0) {
2349 		spin_lock_irqsave(&musb->lock, flags);
2350 		usb_hcd_unlink_urb_from_ep(hcd, urb);
2351 		spin_unlock_irqrestore(&musb->lock, flags);
2352 		kfree(qh);
2353 	}
2354 	return ret;
2355 }
2356 
2357 
2358 /*
2359  * abort a transfer that's at the head of a hardware queue.
2360  * called with controller locked, irqs blocked
2361  * that hardware queue advances to the next transfer, unless prevented
2362  */
musb_cleanup_urb(struct urb * urb,struct musb_qh * qh)2363 static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh)
2364 {
2365 	struct musb_hw_ep	*ep = qh->hw_ep;
2366 	struct musb		*musb = ep->musb;
2367 	void __iomem		*epio = ep->regs;
2368 	unsigned		hw_end = ep->epnum;
2369 	void __iomem		*regs = ep->musb->mregs;
2370 	int			is_in = usb_pipein(urb->pipe);
2371 	int			status = 0;
2372 	u16			csr;
2373 	struct dma_channel	*dma = NULL;
2374 
2375 	musb_ep_select(regs, hw_end);
2376 
2377 	if (is_dma_capable()) {
2378 		dma = is_in ? ep->rx_channel : ep->tx_channel;
2379 		if (dma) {
2380 			status = ep->musb->dma_controller->channel_abort(dma);
2381 			musb_dbg(musb, "abort %cX%d DMA for urb %p --> %d",
2382 				is_in ? 'R' : 'T', ep->epnum,
2383 				urb, status);
2384 			urb->actual_length += dma->actual_len;
2385 		}
2386 	}
2387 
2388 	/* turn off DMA requests, discard state, stop polling ... */
2389 	if (ep->epnum && is_in) {
2390 		/* giveback saves bulk toggle */
2391 		csr = musb_h_flush_rxfifo(ep, 0);
2392 
2393 		/* clear the endpoint's irq status here to avoid bogus irqs */
2394 		if (is_dma_capable() && dma)
2395 			musb_platform_clear_ep_rxintr(musb, ep->epnum);
2396 	} else if (ep->epnum) {
2397 		musb_h_tx_flush_fifo(ep);
2398 		csr = musb_readw(epio, MUSB_TXCSR);
2399 		csr &= ~(MUSB_TXCSR_AUTOSET
2400 			| MUSB_TXCSR_DMAENAB
2401 			| MUSB_TXCSR_H_RXSTALL
2402 			| MUSB_TXCSR_H_NAKTIMEOUT
2403 			| MUSB_TXCSR_H_ERROR
2404 			| MUSB_TXCSR_TXPKTRDY);
2405 		musb_writew(epio, MUSB_TXCSR, csr);
2406 		/* REVISIT may need to clear FLUSHFIFO ... */
2407 		musb_writew(epio, MUSB_TXCSR, csr);
2408 		/* flush cpu writebuffer */
2409 		csr = musb_readw(epio, MUSB_TXCSR);
2410 	} else  {
2411 		musb_h_ep0_flush_fifo(ep);
2412 	}
2413 	if (status == 0)
2414 		musb_advance_schedule(ep->musb, urb, ep, is_in);
2415 	return status;
2416 }
2417 
musb_urb_dequeue(struct usb_hcd * hcd,struct urb * urb,int status)2418 static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
2419 {
2420 	struct musb		*musb = hcd_to_musb(hcd);
2421 	struct musb_qh		*qh;
2422 	unsigned long		flags;
2423 	int			is_in  = usb_pipein(urb->pipe);
2424 	int			ret;
2425 
2426 	trace_musb_urb_deq(musb, urb);
2427 
2428 	spin_lock_irqsave(&musb->lock, flags);
2429 	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
2430 	if (ret)
2431 		goto done;
2432 
2433 	qh = urb->hcpriv;
2434 	if (!qh)
2435 		goto done;
2436 
2437 	/*
2438 	 * Any URB not actively programmed into endpoint hardware can be
2439 	 * immediately given back; that's any URB not at the head of an
2440 	 * endpoint queue, unless someday we get real DMA queues.  And even
2441 	 * if it's at the head, it might not be known to the hardware...
2442 	 *
2443 	 * Otherwise abort current transfer, pending DMA, etc.; urb->status
2444 	 * has already been updated.  This is a synchronous abort; it'd be
2445 	 * OK to hold off until after some IRQ, though.
2446 	 *
2447 	 * NOTE: qh is invalid unless !list_empty(&hep->urb_list)
2448 	 */
2449 	if (!qh->is_ready
2450 			|| urb->urb_list.prev != &qh->hep->urb_list
2451 			|| musb_ep_get_qh(qh->hw_ep, is_in) != qh) {
2452 		int	ready = qh->is_ready;
2453 
2454 		qh->is_ready = 0;
2455 		musb_giveback(musb, urb, 0);
2456 		qh->is_ready = ready;
2457 
2458 		/* If nothing else (usually musb_giveback) is using it
2459 		 * and its URB list has emptied, recycle this qh.
2460 		 */
2461 		if (ready && list_empty(&qh->hep->urb_list)) {
2462 			qh->hep->hcpriv = NULL;
2463 			list_del(&qh->ring);
2464 			kfree(qh);
2465 		}
2466 	} else
2467 		ret = musb_cleanup_urb(urb, qh);
2468 done:
2469 	spin_unlock_irqrestore(&musb->lock, flags);
2470 	return ret;
2471 }
2472 
2473 /* disable an endpoint */
2474 static void
musb_h_disable(struct usb_hcd * hcd,struct usb_host_endpoint * hep)2475 musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
2476 {
2477 	u8			is_in = hep->desc.bEndpointAddress & USB_DIR_IN;
2478 	unsigned long		flags;
2479 	struct musb		*musb = hcd_to_musb(hcd);
2480 	struct musb_qh		*qh;
2481 	struct urb		*urb;
2482 
2483 	spin_lock_irqsave(&musb->lock, flags);
2484 
2485 	qh = hep->hcpriv;
2486 	if (qh == NULL)
2487 		goto exit;
2488 
2489 	/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
2490 
2491 	/* Kick the first URB off the hardware, if needed */
2492 	qh->is_ready = 0;
2493 	if (musb_ep_get_qh(qh->hw_ep, is_in) == qh) {
2494 		urb = next_urb(qh);
2495 
2496 		/* make software (then hardware) stop ASAP */
2497 		if (!urb->unlinked)
2498 			urb->status = -ESHUTDOWN;
2499 
2500 		/* cleanup */
2501 		musb_cleanup_urb(urb, qh);
2502 
2503 		/* Then nuke all the others ... and advance the
2504 		 * queue on hw_ep (e.g. bulk ring) when we're done.
2505 		 */
2506 		while (!list_empty(&hep->urb_list)) {
2507 			urb = next_urb(qh);
2508 			urb->status = -ESHUTDOWN;
2509 			musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
2510 		}
2511 	} else {
2512 		/* Just empty the queue; the hardware is busy with
2513 		 * other transfers, and since !qh->is_ready nothing
2514 		 * will activate any of these as it advances.
2515 		 */
2516 		while (!list_empty(&hep->urb_list))
2517 			musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
2518 
2519 		hep->hcpriv = NULL;
2520 		list_del(&qh->ring);
2521 		kfree(qh);
2522 	}
2523 exit:
2524 	spin_unlock_irqrestore(&musb->lock, flags);
2525 }
2526 
musb_h_get_frame_number(struct usb_hcd * hcd)2527 static int musb_h_get_frame_number(struct usb_hcd *hcd)
2528 {
2529 	struct musb	*musb = hcd_to_musb(hcd);
2530 
2531 	return musb_readw(musb->mregs, MUSB_FRAME);
2532 }
2533 
musb_h_start(struct usb_hcd * hcd)2534 static int musb_h_start(struct usb_hcd *hcd)
2535 {
2536 	struct musb	*musb = hcd_to_musb(hcd);
2537 
2538 	/* NOTE: musb_start() is called when the hub driver turns
2539 	 * on port power, or when (OTG) peripheral starts.
2540 	 */
2541 	hcd->state = HC_STATE_RUNNING;
2542 	musb->port1_status = 0;
2543 	return 0;
2544 }
2545 
musb_h_stop(struct usb_hcd * hcd)2546 static void musb_h_stop(struct usb_hcd *hcd)
2547 {
2548 	musb_stop(hcd_to_musb(hcd));
2549 	hcd->state = HC_STATE_HALT;
2550 }
2551 
musb_bus_suspend(struct usb_hcd * hcd)2552 static int musb_bus_suspend(struct usb_hcd *hcd)
2553 {
2554 	struct musb	*musb = hcd_to_musb(hcd);
2555 	u8		devctl;
2556 	int		ret;
2557 
2558 	ret = musb_port_suspend(musb, true);
2559 	if (ret)
2560 		return ret;
2561 
2562 	if (!is_host_active(musb))
2563 		return 0;
2564 
2565 	switch (musb->xceiv->otg->state) {
2566 	case OTG_STATE_A_SUSPEND:
2567 		return 0;
2568 	case OTG_STATE_A_WAIT_VRISE:
2569 		/* ID could be grounded even if there's no device
2570 		 * on the other end of the cable.  NOTE that the
2571 		 * A_WAIT_VRISE timers are messy with MUSB...
2572 		 */
2573 		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2574 		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2575 			musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
2576 		break;
2577 	default:
2578 		break;
2579 	}
2580 
2581 	if (musb->is_active) {
2582 		WARNING("trying to suspend as %s while active\n",
2583 				usb_otg_state_string(musb->xceiv->otg->state));
2584 		return -EBUSY;
2585 	} else
2586 		return 0;
2587 }
2588 
musb_bus_resume(struct usb_hcd * hcd)2589 static int musb_bus_resume(struct usb_hcd *hcd)
2590 {
2591 	struct musb *musb = hcd_to_musb(hcd);
2592 
2593 	if (musb->config &&
2594 	    musb->config->host_port_deassert_reset_at_resume)
2595 		musb_port_reset(musb, false);
2596 
2597 	return 0;
2598 }
2599 
2600 #ifndef CONFIG_MUSB_PIO_ONLY
2601 
2602 #define MUSB_USB_DMA_ALIGN 4
2603 
2604 struct musb_temp_buffer {
2605 	void *kmalloc_ptr;
2606 	void *old_xfer_buffer;
2607 	u8 data[0];
2608 };
2609 
musb_free_temp_buffer(struct urb * urb)2610 static void musb_free_temp_buffer(struct urb *urb)
2611 {
2612 	enum dma_data_direction dir;
2613 	struct musb_temp_buffer *temp;
2614 	size_t length;
2615 
2616 	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
2617 		return;
2618 
2619 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2620 
2621 	temp = container_of(urb->transfer_buffer, struct musb_temp_buffer,
2622 			    data);
2623 
2624 	if (dir == DMA_FROM_DEVICE) {
2625 		if (usb_pipeisoc(urb->pipe))
2626 			length = urb->transfer_buffer_length;
2627 		else
2628 			length = urb->actual_length;
2629 
2630 		memcpy(temp->old_xfer_buffer, temp->data, length);
2631 	}
2632 	urb->transfer_buffer = temp->old_xfer_buffer;
2633 	kfree(temp->kmalloc_ptr);
2634 
2635 	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
2636 }
2637 
musb_alloc_temp_buffer(struct urb * urb,gfp_t mem_flags)2638 static int musb_alloc_temp_buffer(struct urb *urb, gfp_t mem_flags)
2639 {
2640 	enum dma_data_direction dir;
2641 	struct musb_temp_buffer *temp;
2642 	void *kmalloc_ptr;
2643 	size_t kmalloc_size;
2644 
2645 	if (urb->num_sgs || urb->sg ||
2646 	    urb->transfer_buffer_length == 0 ||
2647 	    !((uintptr_t)urb->transfer_buffer & (MUSB_USB_DMA_ALIGN - 1)))
2648 		return 0;
2649 
2650 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2651 
2652 	/* Allocate a buffer with enough padding for alignment */
2653 	kmalloc_size = urb->transfer_buffer_length +
2654 		sizeof(struct musb_temp_buffer) + MUSB_USB_DMA_ALIGN - 1;
2655 
2656 	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
2657 	if (!kmalloc_ptr)
2658 		return -ENOMEM;
2659 
2660 	/* Position our struct temp_buffer such that data is aligned */
2661 	temp = PTR_ALIGN(kmalloc_ptr, MUSB_USB_DMA_ALIGN);
2662 
2663 
2664 	temp->kmalloc_ptr = kmalloc_ptr;
2665 	temp->old_xfer_buffer = urb->transfer_buffer;
2666 	if (dir == DMA_TO_DEVICE)
2667 		memcpy(temp->data, urb->transfer_buffer,
2668 		       urb->transfer_buffer_length);
2669 	urb->transfer_buffer = temp->data;
2670 
2671 	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
2672 
2673 	return 0;
2674 }
2675 
musb_map_urb_for_dma(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)2676 static int musb_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
2677 				      gfp_t mem_flags)
2678 {
2679 	struct musb	*musb = hcd_to_musb(hcd);
2680 	int ret;
2681 
2682 	/*
2683 	 * The DMA engine in RTL1.8 and above cannot handle
2684 	 * DMA addresses that are not aligned to a 4 byte boundary.
2685 	 * For such engine implemented (un)map_urb_for_dma hooks.
2686 	 * Do not use these hooks for RTL<1.8
2687 	 */
2688 	if (musb->hwvers < MUSB_HWVERS_1800)
2689 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2690 
2691 	ret = musb_alloc_temp_buffer(urb, mem_flags);
2692 	if (ret)
2693 		return ret;
2694 
2695 	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2696 	if (ret)
2697 		musb_free_temp_buffer(urb);
2698 
2699 	return ret;
2700 }
2701 
musb_unmap_urb_for_dma(struct usb_hcd * hcd,struct urb * urb)2702 static void musb_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
2703 {
2704 	struct musb	*musb = hcd_to_musb(hcd);
2705 
2706 	usb_hcd_unmap_urb_for_dma(hcd, urb);
2707 
2708 	/* Do not use this hook for RTL<1.8 (see description above) */
2709 	if (musb->hwvers < MUSB_HWVERS_1800)
2710 		return;
2711 
2712 	musb_free_temp_buffer(urb);
2713 }
2714 #endif /* !CONFIG_MUSB_PIO_ONLY */
2715 
2716 static const struct hc_driver musb_hc_driver = {
2717 	.description		= "musb-hcd",
2718 	.product_desc		= "MUSB HDRC host driver",
2719 	.hcd_priv_size		= sizeof(struct musb *),
2720 	.flags			= HCD_USB2 | HCD_MEMORY,
2721 
2722 	/* not using irq handler or reset hooks from usbcore, since
2723 	 * those must be shared with peripheral code for OTG configs
2724 	 */
2725 
2726 	.start			= musb_h_start,
2727 	.stop			= musb_h_stop,
2728 
2729 	.get_frame_number	= musb_h_get_frame_number,
2730 
2731 	.urb_enqueue		= musb_urb_enqueue,
2732 	.urb_dequeue		= musb_urb_dequeue,
2733 	.endpoint_disable	= musb_h_disable,
2734 
2735 #ifndef CONFIG_MUSB_PIO_ONLY
2736 	.map_urb_for_dma	= musb_map_urb_for_dma,
2737 	.unmap_urb_for_dma	= musb_unmap_urb_for_dma,
2738 #endif
2739 
2740 	.hub_status_data	= musb_hub_status_data,
2741 	.hub_control		= musb_hub_control,
2742 	.bus_suspend		= musb_bus_suspend,
2743 	.bus_resume		= musb_bus_resume,
2744 	/* .start_port_reset	= NULL, */
2745 	/* .hub_irq_enable	= NULL, */
2746 };
2747 
musb_host_alloc(struct musb * musb)2748 int musb_host_alloc(struct musb *musb)
2749 {
2750 	struct device	*dev = musb->controller;
2751 
2752 	/* usbcore sets dev->driver_data to hcd, and sometimes uses that... */
2753 	musb->hcd = usb_create_hcd(&musb_hc_driver, dev, dev_name(dev));
2754 	if (!musb->hcd)
2755 		return -EINVAL;
2756 
2757 	*musb->hcd->hcd_priv = (unsigned long) musb;
2758 	musb->hcd->self.uses_pio_for_control = 1;
2759 	musb->hcd->uses_new_polling = 1;
2760 	musb->hcd->has_tt = 1;
2761 
2762 	return 0;
2763 }
2764 
musb_host_cleanup(struct musb * musb)2765 void musb_host_cleanup(struct musb *musb)
2766 {
2767 	if (musb->port_mode == MUSB_PORT_MODE_GADGET)
2768 		return;
2769 	usb_remove_hcd(musb->hcd);
2770 }
2771 
musb_host_free(struct musb * musb)2772 void musb_host_free(struct musb *musb)
2773 {
2774 	usb_put_hcd(musb->hcd);
2775 }
2776 
musb_host_setup(struct musb * musb,int power_budget)2777 int musb_host_setup(struct musb *musb, int power_budget)
2778 {
2779 	int ret;
2780 	struct usb_hcd *hcd = musb->hcd;
2781 
2782 	if (musb->port_mode == MUSB_PORT_MODE_HOST) {
2783 		MUSB_HST_MODE(musb);
2784 		musb->xceiv->otg->default_a = 1;
2785 		musb->xceiv->otg->state = OTG_STATE_A_IDLE;
2786 	}
2787 	otg_set_host(musb->xceiv->otg, &hcd->self);
2788 	hcd->self.otg_port = 1;
2789 	musb->xceiv->otg->host = &hcd->self;
2790 	hcd->power_budget = 2 * (power_budget ? : 250);
2791 
2792 	ret = usb_add_hcd(hcd, 0, 0);
2793 	if (ret < 0)
2794 		return ret;
2795 
2796 	device_wakeup_enable(hcd->self.controller);
2797 	return 0;
2798 }
2799 
musb_host_resume_root_hub(struct musb * musb)2800 void musb_host_resume_root_hub(struct musb *musb)
2801 {
2802 	usb_hcd_resume_root_hub(musb->hcd);
2803 }
2804 
musb_host_poke_root_hub(struct musb * musb)2805 void musb_host_poke_root_hub(struct musb *musb)
2806 {
2807 	MUSB_HST_MODE(musb);
2808 	if (musb->hcd->status_urb)
2809 		usb_hcd_poll_rh_status(musb->hcd);
2810 	else
2811 		usb_hcd_resume_root_hub(musb->hcd);
2812 }
2813