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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 
48 /* MUSB HOST status 22-mar-2006
49  *
50  * - There's still lots of partial code duplication for fault paths, so
51  *   they aren't handled as consistently as they need to be.
52  *
53  * - PIO mostly behaved when last tested.
54  *     + including ep0, with all usbtest cases 9, 10
55  *     + usbtest 14 (ep0out) doesn't seem to run at all
56  *     + double buffered OUT/TX endpoints saw stalls(!) with certain usbtest
57  *       configurations, but otherwise double buffering passes basic tests.
58  *     + for 2.6.N, for N > ~10, needs API changes for hcd framework.
59  *
60  * - DMA (CPPI) ... partially behaves, not currently recommended
61  *     + about 1/15 the speed of typical EHCI implementations (PCI)
62  *     + RX, all too often reqpkt seems to misbehave after tx
63  *     + TX, no known issues (other than evident silicon issue)
64  *
65  * - DMA (Mentor/OMAP) ...has at least toggle update problems
66  *
67  * - [23-feb-2009] minimal traffic scheduling to avoid bulk RX packet
68  *   starvation ... nothing yet for TX, interrupt, or bulk.
69  *
70  * - Not tested with HNP, but some SRP paths seem to behave.
71  *
72  * NOTE 24-August-2006:
73  *
74  * - Bulk traffic finally uses both sides of hardware ep1, freeing up an
75  *   extra endpoint for periodic use enabling hub + keybd + mouse.  That
76  *   mostly works, except that with "usbnet" it's easy to trigger cases
77  *   with "ping" where RX loses.  (a) ping to davinci, even "ping -f",
78  *   fine; but (b) ping _from_ davinci, even "ping -c 1", ICMP RX loses
79  *   although ARP RX wins.  (That test was done with a full speed link.)
80  */
81 
82 
83 /*
84  * NOTE on endpoint usage:
85  *
86  * CONTROL transfers all go through ep0.  BULK ones go through dedicated IN
87  * and OUT endpoints ... hardware is dedicated for those "async" queue(s).
88  * (Yes, bulk _could_ use more of the endpoints than that, and would even
89  * benefit from it.)
90  *
91  * INTERUPPT and ISOCHRONOUS transfers are scheduled to the other endpoints.
92  * So far that scheduling is both dumb and optimistic:  the endpoint will be
93  * "claimed" until its software queue is no longer refilled.  No multiplexing
94  * of transfers between endpoints, or anything clever.
95  */
96 
hcd_to_musb(struct usb_hcd * hcd)97 struct musb *hcd_to_musb(struct usb_hcd *hcd)
98 {
99 	return *(struct musb **) hcd->hcd_priv;
100 }
101 
102 
103 static void musb_ep_program(struct musb *musb, u8 epnum,
104 			struct urb *urb, int is_out,
105 			u8 *buf, u32 offset, u32 len);
106 
107 /*
108  * Clear TX fifo. Needed to avoid BABBLE errors.
109  */
musb_h_tx_flush_fifo(struct musb_hw_ep * ep)110 static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
111 {
112 	struct musb	*musb = ep->musb;
113 	void __iomem	*epio = ep->regs;
114 	u16		csr;
115 	u16		lastcsr = 0;
116 	int		retries = 1000;
117 
118 	csr = musb_readw(epio, MUSB_TXCSR);
119 	while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
120 		if (csr != lastcsr)
121 			dev_dbg(musb->controller, "Host TX FIFONOTEMPTY csr: %02x\n", csr);
122 		lastcsr = csr;
123 		csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_TXPKTRDY;
124 		musb_writew(epio, MUSB_TXCSR, csr);
125 		csr = musb_readw(epio, MUSB_TXCSR);
126 		if (WARN(retries-- < 1,
127 				"Could not flush host TX%d fifo: csr: %04x\n",
128 				ep->epnum, csr))
129 			return;
130 		mdelay(1);
131 	}
132 }
133 
musb_h_ep0_flush_fifo(struct musb_hw_ep * ep)134 static void musb_h_ep0_flush_fifo(struct musb_hw_ep *ep)
135 {
136 	void __iomem	*epio = ep->regs;
137 	u16		csr;
138 	int		retries = 5;
139 
140 	/* scrub any data left in the fifo */
141 	do {
142 		csr = musb_readw(epio, MUSB_TXCSR);
143 		if (!(csr & (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_RXPKTRDY)))
144 			break;
145 		musb_writew(epio, MUSB_TXCSR, MUSB_CSR0_FLUSHFIFO);
146 		csr = musb_readw(epio, MUSB_TXCSR);
147 		udelay(10);
148 	} while (--retries);
149 
150 	WARN(!retries, "Could not flush host TX%d fifo: csr: %04x\n",
151 			ep->epnum, csr);
152 
153 	/* and reset for the next transfer */
154 	musb_writew(epio, MUSB_TXCSR, 0);
155 }
156 
157 /*
158  * Start transmit. Caller is responsible for locking shared resources.
159  * musb must be locked.
160  */
musb_h_tx_start(struct musb_hw_ep * ep)161 static inline void musb_h_tx_start(struct musb_hw_ep *ep)
162 {
163 	u16	txcsr;
164 
165 	/* NOTE: no locks here; caller should lock and select EP */
166 	if (ep->epnum) {
167 		txcsr = musb_readw(ep->regs, MUSB_TXCSR);
168 		txcsr |= MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_H_WZC_BITS;
169 		musb_writew(ep->regs, MUSB_TXCSR, txcsr);
170 	} else {
171 		txcsr = MUSB_CSR0_H_SETUPPKT | MUSB_CSR0_TXPKTRDY;
172 		musb_writew(ep->regs, MUSB_CSR0, txcsr);
173 	}
174 
175 }
176 
musb_h_tx_dma_start(struct musb_hw_ep * ep)177 static inline void musb_h_tx_dma_start(struct musb_hw_ep *ep)
178 {
179 	u16	txcsr;
180 
181 	/* NOTE: no locks here; caller should lock and select EP */
182 	txcsr = musb_readw(ep->regs, MUSB_TXCSR);
183 	txcsr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_H_WZC_BITS;
184 	if (is_cppi_enabled())
185 		txcsr |= MUSB_TXCSR_DMAMODE;
186 	musb_writew(ep->regs, MUSB_TXCSR, txcsr);
187 }
188 
musb_ep_set_qh(struct musb_hw_ep * ep,int is_in,struct musb_qh * qh)189 static void musb_ep_set_qh(struct musb_hw_ep *ep, int is_in, struct musb_qh *qh)
190 {
191 	if (is_in != 0 || ep->is_shared_fifo)
192 		ep->in_qh  = qh;
193 	if (is_in == 0 || ep->is_shared_fifo)
194 		ep->out_qh = qh;
195 }
196 
musb_ep_get_qh(struct musb_hw_ep * ep,int is_in)197 static struct musb_qh *musb_ep_get_qh(struct musb_hw_ep *ep, int is_in)
198 {
199 	return is_in ? ep->in_qh : ep->out_qh;
200 }
201 
202 /*
203  * Start the URB at the front of an endpoint's queue
204  * end must be claimed from the caller.
205  *
206  * Context: controller locked, irqs blocked
207  */
208 static void
musb_start_urb(struct musb * musb,int is_in,struct musb_qh * qh)209 musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
210 {
211 	u16			frame;
212 	u32			len;
213 	void __iomem		*mbase =  musb->mregs;
214 	struct urb		*urb = next_urb(qh);
215 	void			*buf = urb->transfer_buffer;
216 	u32			offset = 0;
217 	struct musb_hw_ep	*hw_ep = qh->hw_ep;
218 	unsigned		pipe = urb->pipe;
219 	u8			address = usb_pipedevice(pipe);
220 	int			epnum = hw_ep->epnum;
221 
222 	/* initialize software qh state */
223 	qh->offset = 0;
224 	qh->segsize = 0;
225 
226 	/* gather right source of data */
227 	switch (qh->type) {
228 	case USB_ENDPOINT_XFER_CONTROL:
229 		/* control transfers always start with SETUP */
230 		is_in = 0;
231 		musb->ep0_stage = MUSB_EP0_START;
232 		buf = urb->setup_packet;
233 		len = 8;
234 		break;
235 	case USB_ENDPOINT_XFER_ISOC:
236 		qh->iso_idx = 0;
237 		qh->frame = 0;
238 		offset = urb->iso_frame_desc[0].offset;
239 		len = urb->iso_frame_desc[0].length;
240 		break;
241 	default:		/* bulk, interrupt */
242 		/* actual_length may be nonzero on retry paths */
243 		buf = urb->transfer_buffer + urb->actual_length;
244 		len = urb->transfer_buffer_length - urb->actual_length;
245 	}
246 
247 	dev_dbg(musb->controller, "qh %p urb %p dev%d ep%d%s%s, hw_ep %d, %p/%d\n",
248 			qh, urb, address, qh->epnum,
249 			is_in ? "in" : "out",
250 			({char *s; switch (qh->type) {
251 			case USB_ENDPOINT_XFER_CONTROL:	s = ""; break;
252 			case USB_ENDPOINT_XFER_BULK:	s = "-bulk"; break;
253 			case USB_ENDPOINT_XFER_ISOC:	s = "-iso"; break;
254 			default:			s = "-intr"; break;
255 			} s; }),
256 			epnum, buf + offset, len);
257 
258 	/* Configure endpoint */
259 	musb_ep_set_qh(hw_ep, is_in, qh);
260 	musb_ep_program(musb, epnum, urb, !is_in, buf, offset, len);
261 
262 	/* transmit may have more work: start it when it is time */
263 	if (is_in)
264 		return;
265 
266 	/* determine if the time is right for a periodic transfer */
267 	switch (qh->type) {
268 	case USB_ENDPOINT_XFER_ISOC:
269 	case USB_ENDPOINT_XFER_INT:
270 		dev_dbg(musb->controller, "check whether there's still time for periodic Tx\n");
271 		frame = musb_readw(mbase, MUSB_FRAME);
272 		/* FIXME this doesn't implement that scheduling policy ...
273 		 * or handle framecounter wrapping
274 		 */
275 		if (1) {	/* Always assume URB_ISO_ASAP */
276 			/* REVISIT the SOF irq handler shouldn't duplicate
277 			 * this code; and we don't init urb->start_frame...
278 			 */
279 			qh->frame = 0;
280 			goto start;
281 		} else {
282 			qh->frame = urb->start_frame;
283 			/* enable SOF interrupt so we can count down */
284 			dev_dbg(musb->controller, "SOF for %d\n", epnum);
285 #if 1 /* ifndef	CONFIG_ARCH_DAVINCI */
286 			musb_writeb(mbase, MUSB_INTRUSBE, 0xff);
287 #endif
288 		}
289 		break;
290 	default:
291 start:
292 		dev_dbg(musb->controller, "Start TX%d %s\n", epnum,
293 			hw_ep->tx_channel ? "dma" : "pio");
294 
295 		if (!hw_ep->tx_channel)
296 			musb_h_tx_start(hw_ep);
297 		else if (is_cppi_enabled() || tusb_dma_omap())
298 			musb_h_tx_dma_start(hw_ep);
299 	}
300 }
301 
302 /* Context: caller owns controller lock, IRQs are blocked */
musb_giveback(struct musb * musb,struct urb * urb,int status)303 static void musb_giveback(struct musb *musb, struct urb *urb, int status)
304 __releases(musb->lock)
305 __acquires(musb->lock)
306 {
307 	dev_dbg(musb->controller,
308 			"complete %p %pF (%d), dev%d ep%d%s, %d/%d\n",
309 			urb, urb->complete, status,
310 			usb_pipedevice(urb->pipe),
311 			usb_pipeendpoint(urb->pipe),
312 			usb_pipein(urb->pipe) ? "in" : "out",
313 			urb->actual_length, urb->transfer_buffer_length
314 			);
315 
316 	usb_hcd_unlink_urb_from_ep(musb->hcd, urb);
317 	spin_unlock(&musb->lock);
318 	usb_hcd_giveback_urb(musb->hcd, urb, status);
319 	spin_lock(&musb->lock);
320 }
321 
322 /* For bulk/interrupt endpoints only */
musb_save_toggle(struct musb_qh * qh,int is_in,struct urb * urb)323 static inline void musb_save_toggle(struct musb_qh *qh, int is_in,
324 				    struct urb *urb)
325 {
326 	void __iomem		*epio = qh->hw_ep->regs;
327 	u16			csr;
328 
329 	/*
330 	 * FIXME: the current Mentor DMA code seems to have
331 	 * problems getting toggle correct.
332 	 */
333 
334 	if (is_in)
335 		csr = musb_readw(epio, MUSB_RXCSR) & MUSB_RXCSR_H_DATATOGGLE;
336 	else
337 		csr = musb_readw(epio, MUSB_TXCSR) & MUSB_TXCSR_H_DATATOGGLE;
338 
339 	usb_settoggle(urb->dev, qh->epnum, !is_in, csr ? 1 : 0);
340 }
341 
342 /*
343  * Advance this hardware endpoint's queue, completing the specified URB and
344  * advancing to either the next URB queued to that qh, or else invalidating
345  * that qh and advancing to the next qh scheduled after the current one.
346  *
347  * Context: caller owns controller lock, IRQs are blocked
348  */
musb_advance_schedule(struct musb * musb,struct urb * urb,struct musb_hw_ep * hw_ep,int is_in)349 static void musb_advance_schedule(struct musb *musb, struct urb *urb,
350 				  struct musb_hw_ep *hw_ep, int is_in)
351 {
352 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, is_in);
353 	struct musb_hw_ep	*ep = qh->hw_ep;
354 	int			ready = qh->is_ready;
355 	int			status;
356 
357 	status = (urb->status == -EINPROGRESS) ? 0 : urb->status;
358 
359 	/* save toggle eagerly, for paranoia */
360 	switch (qh->type) {
361 	case USB_ENDPOINT_XFER_BULK:
362 	case USB_ENDPOINT_XFER_INT:
363 		musb_save_toggle(qh, is_in, urb);
364 		break;
365 	case USB_ENDPOINT_XFER_ISOC:
366 		if (status == 0 && urb->error_count)
367 			status = -EXDEV;
368 		break;
369 	}
370 
371 	qh->is_ready = 0;
372 	musb_giveback(musb, urb, status);
373 	qh->is_ready = ready;
374 
375 	/* reclaim resources (and bandwidth) ASAP; deschedule it, and
376 	 * invalidate qh as soon as list_empty(&hep->urb_list)
377 	 */
378 	if (list_empty(&qh->hep->urb_list)) {
379 		struct list_head	*head;
380 		struct dma_controller	*dma = musb->dma_controller;
381 
382 		if (is_in) {
383 			ep->rx_reinit = 1;
384 			if (ep->rx_channel) {
385 				dma->channel_release(ep->rx_channel);
386 				ep->rx_channel = NULL;
387 			}
388 		} else {
389 			ep->tx_reinit = 1;
390 			if (ep->tx_channel) {
391 				dma->channel_release(ep->tx_channel);
392 				ep->tx_channel = NULL;
393 			}
394 		}
395 
396 		/* Clobber old pointers to this qh */
397 		musb_ep_set_qh(ep, is_in, NULL);
398 		qh->hep->hcpriv = NULL;
399 
400 		switch (qh->type) {
401 
402 		case USB_ENDPOINT_XFER_CONTROL:
403 		case USB_ENDPOINT_XFER_BULK:
404 			/* fifo policy for these lists, except that NAKing
405 			 * should rotate a qh to the end (for fairness).
406 			 */
407 			if (qh->mux == 1) {
408 				head = qh->ring.prev;
409 				list_del(&qh->ring);
410 				kfree(qh);
411 				qh = first_qh(head);
412 				break;
413 			}
414 
415 		case USB_ENDPOINT_XFER_ISOC:
416 		case USB_ENDPOINT_XFER_INT:
417 			/* this is where periodic bandwidth should be
418 			 * de-allocated if it's tracked and allocated;
419 			 * and where we'd update the schedule tree...
420 			 */
421 			kfree(qh);
422 			qh = NULL;
423 			break;
424 		}
425 	}
426 
427 	if (qh != NULL && qh->is_ready) {
428 		dev_dbg(musb->controller, "... next ep%d %cX urb %p\n",
429 		    hw_ep->epnum, is_in ? 'R' : 'T', next_urb(qh));
430 		musb_start_urb(musb, is_in, qh);
431 	}
432 }
433 
musb_h_flush_rxfifo(struct musb_hw_ep * hw_ep,u16 csr)434 static u16 musb_h_flush_rxfifo(struct musb_hw_ep *hw_ep, u16 csr)
435 {
436 	/* we don't want fifo to fill itself again;
437 	 * ignore dma (various models),
438 	 * leave toggle alone (may not have been saved yet)
439 	 */
440 	csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_RXPKTRDY;
441 	csr &= ~(MUSB_RXCSR_H_REQPKT
442 		| MUSB_RXCSR_H_AUTOREQ
443 		| MUSB_RXCSR_AUTOCLEAR);
444 
445 	/* write 2x to allow double buffering */
446 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
447 	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
448 
449 	/* flush writebuffer */
450 	return musb_readw(hw_ep->regs, MUSB_RXCSR);
451 }
452 
453 /*
454  * PIO RX for a packet (or part of it).
455  */
456 static bool
musb_host_packet_rx(struct musb * musb,struct urb * urb,u8 epnum,u8 iso_err)457 musb_host_packet_rx(struct musb *musb, struct urb *urb, u8 epnum, u8 iso_err)
458 {
459 	u16			rx_count;
460 	u8			*buf;
461 	u16			csr;
462 	bool			done = false;
463 	u32			length;
464 	int			do_flush = 0;
465 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
466 	void __iomem		*epio = hw_ep->regs;
467 	struct musb_qh		*qh = hw_ep->in_qh;
468 	int			pipe = urb->pipe;
469 	void			*buffer = urb->transfer_buffer;
470 
471 	/* musb_ep_select(mbase, epnum); */
472 	rx_count = musb_readw(epio, MUSB_RXCOUNT);
473 	dev_dbg(musb->controller, "RX%d count %d, buffer %p len %d/%d\n", epnum, rx_count,
474 			urb->transfer_buffer, qh->offset,
475 			urb->transfer_buffer_length);
476 
477 	/* unload FIFO */
478 	if (usb_pipeisoc(pipe)) {
479 		int					status = 0;
480 		struct usb_iso_packet_descriptor	*d;
481 
482 		if (iso_err) {
483 			status = -EILSEQ;
484 			urb->error_count++;
485 		}
486 
487 		d = urb->iso_frame_desc + qh->iso_idx;
488 		buf = buffer + d->offset;
489 		length = d->length;
490 		if (rx_count > length) {
491 			if (status == 0) {
492 				status = -EOVERFLOW;
493 				urb->error_count++;
494 			}
495 			dev_dbg(musb->controller, "** OVERFLOW %d into %d\n", rx_count, length);
496 			do_flush = 1;
497 		} else
498 			length = rx_count;
499 		urb->actual_length += length;
500 		d->actual_length = length;
501 
502 		d->status = status;
503 
504 		/* see if we are done */
505 		done = (++qh->iso_idx >= urb->number_of_packets);
506 	} else {
507 		/* non-isoch */
508 		buf = buffer + qh->offset;
509 		length = urb->transfer_buffer_length - qh->offset;
510 		if (rx_count > length) {
511 			if (urb->status == -EINPROGRESS)
512 				urb->status = -EOVERFLOW;
513 			dev_dbg(musb->controller, "** OVERFLOW %d into %d\n", rx_count, length);
514 			do_flush = 1;
515 		} else
516 			length = rx_count;
517 		urb->actual_length += length;
518 		qh->offset += length;
519 
520 		/* see if we are done */
521 		done = (urb->actual_length == urb->transfer_buffer_length)
522 			|| (rx_count < qh->maxpacket)
523 			|| (urb->status != -EINPROGRESS);
524 		if (done
525 				&& (urb->status == -EINPROGRESS)
526 				&& (urb->transfer_flags & URB_SHORT_NOT_OK)
527 				&& (urb->actual_length
528 					< urb->transfer_buffer_length))
529 			urb->status = -EREMOTEIO;
530 	}
531 
532 	musb_read_fifo(hw_ep, length, buf);
533 
534 	csr = musb_readw(epio, MUSB_RXCSR);
535 	csr |= MUSB_RXCSR_H_WZC_BITS;
536 	if (unlikely(do_flush))
537 		musb_h_flush_rxfifo(hw_ep, csr);
538 	else {
539 		/* REVISIT this assumes AUTOCLEAR is never set */
540 		csr &= ~(MUSB_RXCSR_RXPKTRDY | MUSB_RXCSR_H_REQPKT);
541 		if (!done)
542 			csr |= MUSB_RXCSR_H_REQPKT;
543 		musb_writew(epio, MUSB_RXCSR, csr);
544 	}
545 
546 	return done;
547 }
548 
549 /* we don't always need to reinit a given side of an endpoint...
550  * when we do, use tx/rx reinit routine and then construct a new CSR
551  * to address data toggle, NYET, and DMA or PIO.
552  *
553  * it's possible that driver bugs (especially for DMA) or aborting a
554  * transfer might have left the endpoint busier than it should be.
555  * the busy/not-empty tests are basically paranoia.
556  */
557 static void
musb_rx_reinit(struct musb * musb,struct musb_qh * qh,struct musb_hw_ep * ep)558 musb_rx_reinit(struct musb *musb, struct musb_qh *qh, struct musb_hw_ep *ep)
559 {
560 	u16	csr;
561 
562 	/* NOTE:  we know the "rx" fifo reinit never triggers for ep0.
563 	 * That always uses tx_reinit since ep0 repurposes TX register
564 	 * offsets; the initial SETUP packet is also a kind of OUT.
565 	 */
566 
567 	/* if programmed for Tx, put it in RX mode */
568 	if (ep->is_shared_fifo) {
569 		csr = musb_readw(ep->regs, MUSB_TXCSR);
570 		if (csr & MUSB_TXCSR_MODE) {
571 			musb_h_tx_flush_fifo(ep);
572 			csr = musb_readw(ep->regs, MUSB_TXCSR);
573 			musb_writew(ep->regs, MUSB_TXCSR,
574 				    csr | MUSB_TXCSR_FRCDATATOG);
575 		}
576 
577 		/*
578 		 * Clear the MODE bit (and everything else) to enable Rx.
579 		 * NOTE: we mustn't clear the DMAMODE bit before DMAENAB.
580 		 */
581 		if (csr & MUSB_TXCSR_DMAMODE)
582 			musb_writew(ep->regs, MUSB_TXCSR, MUSB_TXCSR_DMAMODE);
583 		musb_writew(ep->regs, MUSB_TXCSR, 0);
584 
585 	/* scrub all previous state, clearing toggle */
586 	}
587 	csr = musb_readw(ep->regs, MUSB_RXCSR);
588 	if (csr & MUSB_RXCSR_RXPKTRDY)
589 		WARNING("rx%d, packet/%d ready?\n", ep->epnum,
590 			musb_readw(ep->regs, MUSB_RXCOUNT));
591 
592 	musb_h_flush_rxfifo(ep, MUSB_RXCSR_CLRDATATOG);
593 
594 	/* target addr and (for multipoint) hub addr/port */
595 	if (musb->is_multipoint) {
596 		musb_write_rxfunaddr(ep->target_regs, qh->addr_reg);
597 		musb_write_rxhubaddr(ep->target_regs, qh->h_addr_reg);
598 		musb_write_rxhubport(ep->target_regs, qh->h_port_reg);
599 
600 	} else
601 		musb_writeb(musb->mregs, MUSB_FADDR, qh->addr_reg);
602 
603 	/* protocol/endpoint, interval/NAKlimit, i/o size */
604 	musb_writeb(ep->regs, MUSB_RXTYPE, qh->type_reg);
605 	musb_writeb(ep->regs, MUSB_RXINTERVAL, qh->intv_reg);
606 	/* NOTE: bulk combining rewrites high bits of maxpacket */
607 	/* Set RXMAXP with the FIFO size of the endpoint
608 	 * to disable double buffer mode.
609 	 */
610 	if (musb->double_buffer_not_ok)
611 		musb_writew(ep->regs, MUSB_RXMAXP, ep->max_packet_sz_rx);
612 	else
613 		musb_writew(ep->regs, MUSB_RXMAXP,
614 				qh->maxpacket | ((qh->hb_mult - 1) << 11));
615 
616 	ep->rx_reinit = 0;
617 }
618 
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)619 static bool musb_tx_dma_program(struct dma_controller *dma,
620 		struct musb_hw_ep *hw_ep, struct musb_qh *qh,
621 		struct urb *urb, u32 offset, u32 length)
622 {
623 	struct dma_channel	*channel = hw_ep->tx_channel;
624 	void __iomem		*epio = hw_ep->regs;
625 	u16			pkt_size = qh->maxpacket;
626 	u16			csr;
627 	u8			mode;
628 
629 #if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA)
630 	if (length > channel->max_len)
631 		length = channel->max_len;
632 
633 	csr = musb_readw(epio, MUSB_TXCSR);
634 	if (length > pkt_size) {
635 		mode = 1;
636 		csr |= MUSB_TXCSR_DMAMODE | MUSB_TXCSR_DMAENAB;
637 		/* autoset shouldn't be set in high bandwidth */
638 		/*
639 		 * Enable Autoset according to table
640 		 * below
641 		 * bulk_split hb_mult	Autoset_Enable
642 		 *	0	1	Yes(Normal)
643 		 *	0	>1	No(High BW ISO)
644 		 *	1	1	Yes(HS bulk)
645 		 *	1	>1	Yes(FS bulk)
646 		 */
647 		if (qh->hb_mult == 1 || (qh->hb_mult > 1 &&
648 					can_bulk_split(hw_ep->musb, qh->type)))
649 			csr |= MUSB_TXCSR_AUTOSET;
650 	} else {
651 		mode = 0;
652 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAMODE);
653 		csr |= MUSB_TXCSR_DMAENAB; /* against programmer's guide */
654 	}
655 	channel->desired_mode = mode;
656 	musb_writew(epio, MUSB_TXCSR, csr);
657 #else
658 	if (!is_cppi_enabled() && !tusb_dma_omap())
659 		return false;
660 
661 	channel->actual_len = 0;
662 
663 	/*
664 	 * TX uses "RNDIS" mode automatically but needs help
665 	 * to identify the zero-length-final-packet case.
666 	 */
667 	mode = (urb->transfer_flags & URB_ZERO_PACKET) ? 1 : 0;
668 #endif
669 
670 	qh->segsize = length;
671 
672 	/*
673 	 * Ensure the data reaches to main memory before starting
674 	 * DMA transfer
675 	 */
676 	wmb();
677 
678 	if (!dma->channel_program(channel, pkt_size, mode,
679 			urb->transfer_dma + offset, length)) {
680 		dma->channel_release(channel);
681 		hw_ep->tx_channel = NULL;
682 
683 		csr = musb_readw(epio, MUSB_TXCSR);
684 		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
685 		musb_writew(epio, MUSB_TXCSR, csr | MUSB_TXCSR_H_WZC_BITS);
686 		return false;
687 	}
688 	return true;
689 }
690 
691 /*
692  * Program an HDRC endpoint as per the given URB
693  * Context: irqs blocked, controller lock held
694  */
musb_ep_program(struct musb * musb,u8 epnum,struct urb * urb,int is_out,u8 * buf,u32 offset,u32 len)695 static void musb_ep_program(struct musb *musb, u8 epnum,
696 			struct urb *urb, int is_out,
697 			u8 *buf, u32 offset, u32 len)
698 {
699 	struct dma_controller	*dma_controller;
700 	struct dma_channel	*dma_channel;
701 	u8			dma_ok;
702 	void __iomem		*mbase = musb->mregs;
703 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
704 	void __iomem		*epio = hw_ep->regs;
705 	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, !is_out);
706 	u16			packet_sz = qh->maxpacket;
707 	u8			use_dma = 1;
708 	u16			csr;
709 
710 	dev_dbg(musb->controller, "%s hw%d urb %p spd%d dev%d ep%d%s "
711 				"h_addr%02x h_port%02x bytes %d\n",
712 			is_out ? "-->" : "<--",
713 			epnum, urb, urb->dev->speed,
714 			qh->addr_reg, qh->epnum, is_out ? "out" : "in",
715 			qh->h_addr_reg, qh->h_port_reg,
716 			len);
717 
718 	musb_ep_select(mbase, epnum);
719 
720 	if (is_out && !len) {
721 		use_dma = 0;
722 		csr = musb_readw(epio, MUSB_TXCSR);
723 		csr &= ~MUSB_TXCSR_DMAENAB;
724 		musb_writew(epio, MUSB_TXCSR, csr);
725 		hw_ep->tx_channel = NULL;
726 	}
727 
728 	/* candidate for DMA? */
729 	dma_controller = musb->dma_controller;
730 	if (use_dma && is_dma_capable() && epnum && dma_controller) {
731 		dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel;
732 		if (!dma_channel) {
733 			dma_channel = dma_controller->channel_alloc(
734 					dma_controller, hw_ep, is_out);
735 			if (is_out)
736 				hw_ep->tx_channel = dma_channel;
737 			else
738 				hw_ep->rx_channel = dma_channel;
739 		}
740 	} else
741 		dma_channel = NULL;
742 
743 	/* make sure we clear DMAEnab, autoSet bits from previous run */
744 
745 	/* OUT/transmit/EP0 or IN/receive? */
746 	if (is_out) {
747 		u16	csr;
748 		u16	int_txe;
749 		u16	load_count;
750 
751 		csr = musb_readw(epio, MUSB_TXCSR);
752 
753 		/* disable interrupt in case we flush */
754 		int_txe = musb->intrtxe;
755 		musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
756 
757 		/* general endpoint setup */
758 		if (epnum) {
759 			/* flush all old state, set default */
760 			/*
761 			 * We could be flushing valid
762 			 * packets in double buffering
763 			 * case
764 			 */
765 			if (!hw_ep->tx_double_buffered)
766 				musb_h_tx_flush_fifo(hw_ep);
767 
768 			/*
769 			 * We must not clear the DMAMODE bit before or in
770 			 * the same cycle with the DMAENAB bit, so we clear
771 			 * the latter first...
772 			 */
773 			csr &= ~(MUSB_TXCSR_H_NAKTIMEOUT
774 					| MUSB_TXCSR_AUTOSET
775 					| MUSB_TXCSR_DMAENAB
776 					| MUSB_TXCSR_FRCDATATOG
777 					| MUSB_TXCSR_H_RXSTALL
778 					| MUSB_TXCSR_H_ERROR
779 					| MUSB_TXCSR_TXPKTRDY
780 					);
781 			csr |= MUSB_TXCSR_MODE;
782 
783 			if (!hw_ep->tx_double_buffered) {
784 				if (usb_gettoggle(urb->dev, qh->epnum, 1))
785 					csr |= MUSB_TXCSR_H_WR_DATATOGGLE
786 						| MUSB_TXCSR_H_DATATOGGLE;
787 				else
788 					csr |= MUSB_TXCSR_CLRDATATOG;
789 			}
790 
791 			musb_writew(epio, MUSB_TXCSR, csr);
792 			/* REVISIT may need to clear FLUSHFIFO ... */
793 			csr &= ~MUSB_TXCSR_DMAMODE;
794 			musb_writew(epio, MUSB_TXCSR, csr);
795 			csr = musb_readw(epio, MUSB_TXCSR);
796 		} else {
797 			/* endpoint 0: just flush */
798 			musb_h_ep0_flush_fifo(hw_ep);
799 		}
800 
801 		/* target addr and (for multipoint) hub addr/port */
802 		if (musb->is_multipoint) {
803 			musb_write_txfunaddr(mbase, epnum, qh->addr_reg);
804 			musb_write_txhubaddr(mbase, epnum, qh->h_addr_reg);
805 			musb_write_txhubport(mbase, epnum, qh->h_port_reg);
806 /* FIXME if !epnum, do the same for RX ... */
807 		} else
808 			musb_writeb(mbase, MUSB_FADDR, qh->addr_reg);
809 
810 		/* protocol/endpoint/interval/NAKlimit */
811 		if (epnum) {
812 			musb_writeb(epio, MUSB_TXTYPE, qh->type_reg);
813 			if (musb->double_buffer_not_ok) {
814 				musb_writew(epio, MUSB_TXMAXP,
815 						hw_ep->max_packet_sz_tx);
816 			} else if (can_bulk_split(musb, qh->type)) {
817 				qh->hb_mult = hw_ep->max_packet_sz_tx
818 						/ packet_sz;
819 				musb_writew(epio, MUSB_TXMAXP, packet_sz
820 					| ((qh->hb_mult) - 1) << 11);
821 			} else {
822 				musb_writew(epio, MUSB_TXMAXP,
823 						qh->maxpacket |
824 						((qh->hb_mult - 1) << 11));
825 			}
826 			musb_writeb(epio, MUSB_TXINTERVAL, qh->intv_reg);
827 		} else {
828 			musb_writeb(epio, MUSB_NAKLIMIT0, qh->intv_reg);
829 			if (musb->is_multipoint)
830 				musb_writeb(epio, MUSB_TYPE0,
831 						qh->type_reg);
832 		}
833 
834 		if (can_bulk_split(musb, qh->type))
835 			load_count = min((u32) hw_ep->max_packet_sz_tx,
836 						len);
837 		else
838 			load_count = min((u32) packet_sz, len);
839 
840 		if (dma_channel && musb_tx_dma_program(dma_controller,
841 					hw_ep, qh, urb, offset, len))
842 			load_count = 0;
843 
844 		if (load_count) {
845 			/* PIO to load FIFO */
846 			qh->segsize = load_count;
847 			if (!buf) {
848 				sg_miter_start(&qh->sg_miter, urb->sg, 1,
849 						SG_MITER_ATOMIC
850 						| SG_MITER_FROM_SG);
851 				if (!sg_miter_next(&qh->sg_miter)) {
852 					dev_err(musb->controller,
853 							"error: sg"
854 							"list empty\n");
855 					sg_miter_stop(&qh->sg_miter);
856 					goto finish;
857 				}
858 				buf = qh->sg_miter.addr + urb->sg->offset +
859 					urb->actual_length;
860 				load_count = min_t(u32, load_count,
861 						qh->sg_miter.length);
862 				musb_write_fifo(hw_ep, load_count, buf);
863 				qh->sg_miter.consumed = load_count;
864 				sg_miter_stop(&qh->sg_miter);
865 			} else
866 				musb_write_fifo(hw_ep, load_count, buf);
867 		}
868 finish:
869 		/* re-enable interrupt */
870 		musb_writew(mbase, MUSB_INTRTXE, int_txe);
871 
872 	/* IN/receive */
873 	} else {
874 		u16	csr;
875 
876 		if (hw_ep->rx_reinit) {
877 			musb_rx_reinit(musb, qh, hw_ep);
878 
879 			/* init new state: toggle and NYET, maybe DMA later */
880 			if (usb_gettoggle(urb->dev, qh->epnum, 0))
881 				csr = MUSB_RXCSR_H_WR_DATATOGGLE
882 					| MUSB_RXCSR_H_DATATOGGLE;
883 			else
884 				csr = 0;
885 			if (qh->type == USB_ENDPOINT_XFER_INT)
886 				csr |= MUSB_RXCSR_DISNYET;
887 
888 		} else {
889 			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
890 
891 			if (csr & (MUSB_RXCSR_RXPKTRDY
892 					| MUSB_RXCSR_DMAENAB
893 					| MUSB_RXCSR_H_REQPKT))
894 				ERR("broken !rx_reinit, ep%d csr %04x\n",
895 						hw_ep->epnum, csr);
896 
897 			/* scrub any stale state, leaving toggle alone */
898 			csr &= MUSB_RXCSR_DISNYET;
899 		}
900 
901 		/* kick things off */
902 
903 		if ((is_cppi_enabled() || tusb_dma_omap()) && dma_channel) {
904 			/* Candidate for DMA */
905 			dma_channel->actual_len = 0L;
906 			qh->segsize = len;
907 
908 			/* AUTOREQ is in a DMA register */
909 			musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
910 			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
911 
912 			/*
913 			 * Unless caller treats short RX transfers as
914 			 * errors, we dare not queue multiple transfers.
915 			 */
916 			dma_ok = dma_controller->channel_program(dma_channel,
917 					packet_sz, !(urb->transfer_flags &
918 						     URB_SHORT_NOT_OK),
919 					urb->transfer_dma + offset,
920 					qh->segsize);
921 			if (!dma_ok) {
922 				dma_controller->channel_release(dma_channel);
923 				hw_ep->rx_channel = dma_channel = NULL;
924 			} else
925 				csr |= MUSB_RXCSR_DMAENAB;
926 		}
927 
928 		csr |= MUSB_RXCSR_H_REQPKT;
929 		dev_dbg(musb->controller, "RXCSR%d := %04x\n", epnum, csr);
930 		musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
931 		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
932 	}
933 }
934 
935 /* Schedule next QH from musb->in_bulk/out_bulk and move the current qh to
936  * the end; avoids starvation for other endpoints.
937  */
musb_bulk_nak_timeout(struct musb * musb,struct musb_hw_ep * ep,int is_in)938 static void musb_bulk_nak_timeout(struct musb *musb, struct musb_hw_ep *ep,
939 	int is_in)
940 {
941 	struct dma_channel	*dma;
942 	struct urb		*urb;
943 	void __iomem		*mbase = musb->mregs;
944 	void __iomem		*epio = ep->regs;
945 	struct musb_qh		*cur_qh, *next_qh;
946 	u16			rx_csr, tx_csr;
947 
948 	musb_ep_select(mbase, ep->epnum);
949 	if (is_in) {
950 		dma = is_dma_capable() ? ep->rx_channel : NULL;
951 
952 		/*
953 		 * Need to stop the transaction by clearing REQPKT first
954 		 * then the NAK Timeout bit ref MUSBMHDRC USB 2.0 HIGH-SPEED
955 		 * DUAL-ROLE CONTROLLER Programmer's Guide, section 9.2.2
956 		 */
957 		rx_csr = musb_readw(epio, MUSB_RXCSR);
958 		rx_csr |= MUSB_RXCSR_H_WZC_BITS;
959 		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
960 		musb_writew(epio, MUSB_RXCSR, rx_csr);
961 		rx_csr &= ~MUSB_RXCSR_DATAERROR;
962 		musb_writew(epio, MUSB_RXCSR, rx_csr);
963 
964 		cur_qh = first_qh(&musb->in_bulk);
965 	} else {
966 		dma = is_dma_capable() ? ep->tx_channel : NULL;
967 
968 		/* clear nak timeout bit */
969 		tx_csr = musb_readw(epio, MUSB_TXCSR);
970 		tx_csr |= MUSB_TXCSR_H_WZC_BITS;
971 		tx_csr &= ~MUSB_TXCSR_H_NAKTIMEOUT;
972 		musb_writew(epio, MUSB_TXCSR, tx_csr);
973 
974 		cur_qh = first_qh(&musb->out_bulk);
975 	}
976 	if (cur_qh) {
977 		urb = next_urb(cur_qh);
978 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
979 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
980 			musb->dma_controller->channel_abort(dma);
981 			urb->actual_length += dma->actual_len;
982 			dma->actual_len = 0L;
983 		}
984 		musb_save_toggle(cur_qh, is_in, urb);
985 
986 		if (is_in) {
987 			/* move cur_qh to end of queue */
988 			list_move_tail(&cur_qh->ring, &musb->in_bulk);
989 
990 			/* get the next qh from musb->in_bulk */
991 			next_qh = first_qh(&musb->in_bulk);
992 
993 			/* set rx_reinit and schedule the next qh */
994 			ep->rx_reinit = 1;
995 		} else {
996 			/* move cur_qh to end of queue */
997 			list_move_tail(&cur_qh->ring, &musb->out_bulk);
998 
999 			/* get the next qh from musb->out_bulk */
1000 			next_qh = first_qh(&musb->out_bulk);
1001 
1002 			/* set tx_reinit and schedule the next qh */
1003 			ep->tx_reinit = 1;
1004 		}
1005 		musb_start_urb(musb, is_in, next_qh);
1006 	}
1007 }
1008 
1009 /*
1010  * Service the default endpoint (ep0) as host.
1011  * Return true until it's time to start the status stage.
1012  */
musb_h_ep0_continue(struct musb * musb,u16 len,struct urb * urb)1013 static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
1014 {
1015 	bool			 more = false;
1016 	u8			*fifo_dest = NULL;
1017 	u16			fifo_count = 0;
1018 	struct musb_hw_ep	*hw_ep = musb->control_ep;
1019 	struct musb_qh		*qh = hw_ep->in_qh;
1020 	struct usb_ctrlrequest	*request;
1021 
1022 	switch (musb->ep0_stage) {
1023 	case MUSB_EP0_IN:
1024 		fifo_dest = urb->transfer_buffer + urb->actual_length;
1025 		fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
1026 				   urb->actual_length);
1027 		if (fifo_count < len)
1028 			urb->status = -EOVERFLOW;
1029 
1030 		musb_read_fifo(hw_ep, fifo_count, fifo_dest);
1031 
1032 		urb->actual_length += fifo_count;
1033 		if (len < qh->maxpacket) {
1034 			/* always terminate on short read; it's
1035 			 * rarely reported as an error.
1036 			 */
1037 		} else if (urb->actual_length <
1038 				urb->transfer_buffer_length)
1039 			more = true;
1040 		break;
1041 	case MUSB_EP0_START:
1042 		request = (struct usb_ctrlrequest *) urb->setup_packet;
1043 
1044 		if (!request->wLength) {
1045 			dev_dbg(musb->controller, "start no-DATA\n");
1046 			break;
1047 		} else if (request->bRequestType & USB_DIR_IN) {
1048 			dev_dbg(musb->controller, "start IN-DATA\n");
1049 			musb->ep0_stage = MUSB_EP0_IN;
1050 			more = true;
1051 			break;
1052 		} else {
1053 			dev_dbg(musb->controller, "start OUT-DATA\n");
1054 			musb->ep0_stage = MUSB_EP0_OUT;
1055 			more = true;
1056 		}
1057 		/* FALLTHROUGH */
1058 	case MUSB_EP0_OUT:
1059 		fifo_count = min_t(size_t, qh->maxpacket,
1060 				   urb->transfer_buffer_length -
1061 				   urb->actual_length);
1062 		if (fifo_count) {
1063 			fifo_dest = (u8 *) (urb->transfer_buffer
1064 					+ urb->actual_length);
1065 			dev_dbg(musb->controller, "Sending %d byte%s to ep0 fifo %p\n",
1066 					fifo_count,
1067 					(fifo_count == 1) ? "" : "s",
1068 					fifo_dest);
1069 			musb_write_fifo(hw_ep, fifo_count, fifo_dest);
1070 
1071 			urb->actual_length += fifo_count;
1072 			more = true;
1073 		}
1074 		break;
1075 	default:
1076 		ERR("bogus ep0 stage %d\n", musb->ep0_stage);
1077 		break;
1078 	}
1079 
1080 	return more;
1081 }
1082 
1083 /*
1084  * Handle default endpoint interrupt as host. Only called in IRQ time
1085  * from musb_interrupt().
1086  *
1087  * called with controller irqlocked
1088  */
musb_h_ep0_irq(struct musb * musb)1089 irqreturn_t musb_h_ep0_irq(struct musb *musb)
1090 {
1091 	struct urb		*urb;
1092 	u16			csr, len;
1093 	int			status = 0;
1094 	void __iomem		*mbase = musb->mregs;
1095 	struct musb_hw_ep	*hw_ep = musb->control_ep;
1096 	void __iomem		*epio = hw_ep->regs;
1097 	struct musb_qh		*qh = hw_ep->in_qh;
1098 	bool			complete = false;
1099 	irqreturn_t		retval = IRQ_NONE;
1100 
1101 	/* ep0 only has one queue, "in" */
1102 	urb = next_urb(qh);
1103 
1104 	musb_ep_select(mbase, 0);
1105 	csr = musb_readw(epio, MUSB_CSR0);
1106 	len = (csr & MUSB_CSR0_RXPKTRDY)
1107 			? musb_readb(epio, MUSB_COUNT0)
1108 			: 0;
1109 
1110 	dev_dbg(musb->controller, "<== csr0 %04x, qh %p, count %d, urb %p, stage %d\n",
1111 		csr, qh, len, urb, musb->ep0_stage);
1112 
1113 	/* if we just did status stage, we are done */
1114 	if (MUSB_EP0_STATUS == musb->ep0_stage) {
1115 		retval = IRQ_HANDLED;
1116 		complete = true;
1117 	}
1118 
1119 	/* prepare status */
1120 	if (csr & MUSB_CSR0_H_RXSTALL) {
1121 		dev_dbg(musb->controller, "STALLING ENDPOINT\n");
1122 		status = -EPIPE;
1123 
1124 	} else if (csr & MUSB_CSR0_H_ERROR) {
1125 		dev_dbg(musb->controller, "no response, csr0 %04x\n", csr);
1126 		status = -EPROTO;
1127 
1128 	} else if (csr & MUSB_CSR0_H_NAKTIMEOUT) {
1129 		dev_dbg(musb->controller, "control NAK timeout\n");
1130 
1131 		/* NOTE:  this code path would be a good place to PAUSE a
1132 		 * control transfer, if another one is queued, so that
1133 		 * ep0 is more likely to stay busy.  That's already done
1134 		 * for bulk RX transfers.
1135 		 *
1136 		 * if (qh->ring.next != &musb->control), then
1137 		 * we have a candidate... NAKing is *NOT* an error
1138 		 */
1139 		musb_writew(epio, MUSB_CSR0, 0);
1140 		retval = IRQ_HANDLED;
1141 	}
1142 
1143 	if (status) {
1144 		dev_dbg(musb->controller, "aborting\n");
1145 		retval = IRQ_HANDLED;
1146 		if (urb)
1147 			urb->status = status;
1148 		complete = true;
1149 
1150 		/* use the proper sequence to abort the transfer */
1151 		if (csr & MUSB_CSR0_H_REQPKT) {
1152 			csr &= ~MUSB_CSR0_H_REQPKT;
1153 			musb_writew(epio, MUSB_CSR0, csr);
1154 			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1155 			musb_writew(epio, MUSB_CSR0, csr);
1156 		} else {
1157 			musb_h_ep0_flush_fifo(hw_ep);
1158 		}
1159 
1160 		musb_writeb(epio, MUSB_NAKLIMIT0, 0);
1161 
1162 		/* clear it */
1163 		musb_writew(epio, MUSB_CSR0, 0);
1164 	}
1165 
1166 	if (unlikely(!urb)) {
1167 		/* stop endpoint since we have no place for its data, this
1168 		 * SHOULD NEVER HAPPEN! */
1169 		ERR("no URB for end 0\n");
1170 
1171 		musb_h_ep0_flush_fifo(hw_ep);
1172 		goto done;
1173 	}
1174 
1175 	if (!complete) {
1176 		/* call common logic and prepare response */
1177 		if (musb_h_ep0_continue(musb, len, urb)) {
1178 			/* more packets required */
1179 			csr = (MUSB_EP0_IN == musb->ep0_stage)
1180 				?  MUSB_CSR0_H_REQPKT : MUSB_CSR0_TXPKTRDY;
1181 		} else {
1182 			/* data transfer complete; perform status phase */
1183 			if (usb_pipeout(urb->pipe)
1184 					|| !urb->transfer_buffer_length)
1185 				csr = MUSB_CSR0_H_STATUSPKT
1186 					| MUSB_CSR0_H_REQPKT;
1187 			else
1188 				csr = MUSB_CSR0_H_STATUSPKT
1189 					| MUSB_CSR0_TXPKTRDY;
1190 
1191 			/* disable ping token in status phase */
1192 			csr |= MUSB_CSR0_H_DIS_PING;
1193 
1194 			/* flag status stage */
1195 			musb->ep0_stage = MUSB_EP0_STATUS;
1196 
1197 			dev_dbg(musb->controller, "ep0 STATUS, csr %04x\n", csr);
1198 
1199 		}
1200 		musb_writew(epio, MUSB_CSR0, csr);
1201 		retval = IRQ_HANDLED;
1202 	} else
1203 		musb->ep0_stage = MUSB_EP0_IDLE;
1204 
1205 	/* call completion handler if done */
1206 	if (complete)
1207 		musb_advance_schedule(musb, urb, hw_ep, 1);
1208 done:
1209 	return retval;
1210 }
1211 
1212 
1213 #ifdef CONFIG_USB_INVENTRA_DMA
1214 
1215 /* Host side TX (OUT) using Mentor DMA works as follows:
1216 	submit_urb ->
1217 		- if queue was empty, Program Endpoint
1218 		- ... which starts DMA to fifo in mode 1 or 0
1219 
1220 	DMA Isr (transfer complete) -> TxAvail()
1221 		- Stop DMA (~DmaEnab)	(<--- Alert ... currently happens
1222 					only in musb_cleanup_urb)
1223 		- TxPktRdy has to be set in mode 0 or for
1224 			short packets in mode 1.
1225 */
1226 
1227 #endif
1228 
1229 /* Service a Tx-Available or dma completion irq for the endpoint */
musb_host_tx(struct musb * musb,u8 epnum)1230 void musb_host_tx(struct musb *musb, u8 epnum)
1231 {
1232 	int			pipe;
1233 	bool			done = false;
1234 	u16			tx_csr;
1235 	size_t			length = 0;
1236 	size_t			offset = 0;
1237 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1238 	void __iomem		*epio = hw_ep->regs;
1239 	struct musb_qh		*qh = hw_ep->out_qh;
1240 	struct urb		*urb = next_urb(qh);
1241 	u32			status = 0;
1242 	void __iomem		*mbase = musb->mregs;
1243 	struct dma_channel	*dma;
1244 	bool			transfer_pending = false;
1245 
1246 	musb_ep_select(mbase, epnum);
1247 	tx_csr = musb_readw(epio, MUSB_TXCSR);
1248 
1249 	/* with CPPI, DMA sometimes triggers "extra" irqs */
1250 	if (!urb) {
1251 		dev_dbg(musb->controller, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1252 		return;
1253 	}
1254 
1255 	pipe = urb->pipe;
1256 	dma = is_dma_capable() ? hw_ep->tx_channel : NULL;
1257 	dev_dbg(musb->controller, "OUT/TX%d end, csr %04x%s\n", epnum, tx_csr,
1258 			dma ? ", dma" : "");
1259 
1260 	/* check for errors */
1261 	if (tx_csr & MUSB_TXCSR_H_RXSTALL) {
1262 		/* dma was disabled, fifo flushed */
1263 		dev_dbg(musb->controller, "TX end %d stall\n", epnum);
1264 
1265 		/* stall; record URB status */
1266 		status = -EPIPE;
1267 
1268 	} else if (tx_csr & MUSB_TXCSR_H_ERROR) {
1269 		/* (NON-ISO) dma was disabled, fifo flushed */
1270 		dev_dbg(musb->controller, "TX 3strikes on ep=%d\n", epnum);
1271 
1272 		status = -ETIMEDOUT;
1273 
1274 	} else if (tx_csr & MUSB_TXCSR_H_NAKTIMEOUT) {
1275 		if (USB_ENDPOINT_XFER_BULK == qh->type && qh->mux == 1
1276 				&& !list_is_singular(&musb->out_bulk)) {
1277 			dev_dbg(musb->controller,
1278 				"NAK timeout on TX%d ep\n", epnum);
1279 			musb_bulk_nak_timeout(musb, hw_ep, 0);
1280 		} else {
1281 			dev_dbg(musb->controller,
1282 				"TX end=%d device not responding\n", epnum);
1283 			/* NOTE:  this code path would be a good place to PAUSE a
1284 			 * transfer, if there's some other (nonperiodic) tx urb
1285 			 * that could use this fifo.  (dma complicates it...)
1286 			 * That's already done for bulk RX transfers.
1287 			 *
1288 			 * if (bulk && qh->ring.next != &musb->out_bulk), then
1289 			 * we have a candidate... NAKing is *NOT* an error
1290 			 */
1291 			musb_ep_select(mbase, epnum);
1292 			musb_writew(epio, MUSB_TXCSR,
1293 					MUSB_TXCSR_H_WZC_BITS
1294 					| MUSB_TXCSR_TXPKTRDY);
1295 		}
1296 			return;
1297 	}
1298 
1299 done:
1300 	if (status) {
1301 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1302 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1303 			musb->dma_controller->channel_abort(dma);
1304 		}
1305 
1306 		/* do the proper sequence to abort the transfer in the
1307 		 * usb core; the dma engine should already be stopped.
1308 		 */
1309 		musb_h_tx_flush_fifo(hw_ep);
1310 		tx_csr &= ~(MUSB_TXCSR_AUTOSET
1311 				| MUSB_TXCSR_DMAENAB
1312 				| MUSB_TXCSR_H_ERROR
1313 				| MUSB_TXCSR_H_RXSTALL
1314 				| MUSB_TXCSR_H_NAKTIMEOUT
1315 				);
1316 
1317 		musb_ep_select(mbase, epnum);
1318 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1319 		/* REVISIT may need to clear FLUSHFIFO ... */
1320 		musb_writew(epio, MUSB_TXCSR, tx_csr);
1321 		musb_writeb(epio, MUSB_TXINTERVAL, 0);
1322 
1323 		done = true;
1324 	}
1325 
1326 	/* second cppi case */
1327 	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1328 		dev_dbg(musb->controller, "extra TX%d ready, csr %04x\n", epnum, tx_csr);
1329 		return;
1330 	}
1331 
1332 	if (is_dma_capable() && dma && !status) {
1333 		/*
1334 		 * DMA has completed.  But if we're using DMA mode 1 (multi
1335 		 * packet DMA), we need a terminal TXPKTRDY interrupt before
1336 		 * we can consider this transfer completed, lest we trash
1337 		 * its last packet when writing the next URB's data.  So we
1338 		 * switch back to mode 0 to get that interrupt; we'll come
1339 		 * back here once it happens.
1340 		 */
1341 		if (tx_csr & MUSB_TXCSR_DMAMODE) {
1342 			/*
1343 			 * We shouldn't clear DMAMODE with DMAENAB set; so
1344 			 * clear them in a safe order.  That should be OK
1345 			 * once TXPKTRDY has been set (and I've never seen
1346 			 * it being 0 at this moment -- DMA interrupt latency
1347 			 * is significant) but if it hasn't been then we have
1348 			 * no choice but to stop being polite and ignore the
1349 			 * programmer's guide... :-)
1350 			 *
1351 			 * Note that we must write TXCSR with TXPKTRDY cleared
1352 			 * in order not to re-trigger the packet send (this bit
1353 			 * can't be cleared by CPU), and there's another caveat:
1354 			 * TXPKTRDY may be set shortly and then cleared in the
1355 			 * double-buffered FIFO mode, so we do an extra TXCSR
1356 			 * read for debouncing...
1357 			 */
1358 			tx_csr &= musb_readw(epio, MUSB_TXCSR);
1359 			if (tx_csr & MUSB_TXCSR_TXPKTRDY) {
1360 				tx_csr &= ~(MUSB_TXCSR_DMAENAB |
1361 					    MUSB_TXCSR_TXPKTRDY);
1362 				musb_writew(epio, MUSB_TXCSR,
1363 					    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1364 			}
1365 			tx_csr &= ~(MUSB_TXCSR_DMAMODE |
1366 				    MUSB_TXCSR_TXPKTRDY);
1367 			musb_writew(epio, MUSB_TXCSR,
1368 				    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1369 
1370 			/*
1371 			 * There is no guarantee that we'll get an interrupt
1372 			 * after clearing DMAMODE as we might have done this
1373 			 * too late (after TXPKTRDY was cleared by controller).
1374 			 * Re-read TXCSR as we have spoiled its previous value.
1375 			 */
1376 			tx_csr = musb_readw(epio, MUSB_TXCSR);
1377 		}
1378 
1379 		/*
1380 		 * We may get here from a DMA completion or TXPKTRDY interrupt.
1381 		 * In any case, we must check the FIFO status here and bail out
1382 		 * only if the FIFO still has data -- that should prevent the
1383 		 * "missed" TXPKTRDY interrupts and deal with double-buffered
1384 		 * FIFO mode too...
1385 		 */
1386 		if (tx_csr & (MUSB_TXCSR_FIFONOTEMPTY | MUSB_TXCSR_TXPKTRDY)) {
1387 			dev_dbg(musb->controller, "DMA complete but packet still in FIFO, "
1388 			    "CSR %04x\n", tx_csr);
1389 			return;
1390 		}
1391 	}
1392 
1393 	if (!status || dma || usb_pipeisoc(pipe)) {
1394 		if (dma)
1395 			length = dma->actual_len;
1396 		else
1397 			length = qh->segsize;
1398 		qh->offset += length;
1399 
1400 		if (usb_pipeisoc(pipe)) {
1401 			struct usb_iso_packet_descriptor	*d;
1402 
1403 			d = urb->iso_frame_desc + qh->iso_idx;
1404 			d->actual_length = length;
1405 			d->status = status;
1406 			if (++qh->iso_idx >= urb->number_of_packets) {
1407 				done = true;
1408 			} else {
1409 				d++;
1410 				offset = d->offset;
1411 				length = d->length;
1412 			}
1413 		} else if (dma && urb->transfer_buffer_length == qh->offset) {
1414 			done = true;
1415 		} else {
1416 			/* see if we need to send more data, or ZLP */
1417 			if (qh->segsize < qh->maxpacket)
1418 				done = true;
1419 			else if (qh->offset == urb->transfer_buffer_length
1420 					&& !(urb->transfer_flags
1421 						& URB_ZERO_PACKET))
1422 				done = true;
1423 			if (!done) {
1424 				offset = qh->offset;
1425 				length = urb->transfer_buffer_length - offset;
1426 				transfer_pending = true;
1427 			}
1428 		}
1429 	}
1430 
1431 	/* urb->status != -EINPROGRESS means request has been faulted,
1432 	 * so we must abort this transfer after cleanup
1433 	 */
1434 	if (urb->status != -EINPROGRESS) {
1435 		done = true;
1436 		if (status == 0)
1437 			status = urb->status;
1438 	}
1439 
1440 	if (done) {
1441 		/* set status */
1442 		urb->status = status;
1443 		urb->actual_length = qh->offset;
1444 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_OUT);
1445 		return;
1446 	} else if ((usb_pipeisoc(pipe) || transfer_pending) && dma) {
1447 		if (musb_tx_dma_program(musb->dma_controller, hw_ep, qh, urb,
1448 				offset, length)) {
1449 			if (is_cppi_enabled() || tusb_dma_omap())
1450 				musb_h_tx_dma_start(hw_ep);
1451 			return;
1452 		}
1453 	} else	if (tx_csr & MUSB_TXCSR_DMAENAB) {
1454 		dev_dbg(musb->controller, "not complete, but DMA enabled?\n");
1455 		return;
1456 	}
1457 
1458 	/*
1459 	 * PIO: start next packet in this URB.
1460 	 *
1461 	 * REVISIT: some docs say that when hw_ep->tx_double_buffered,
1462 	 * (and presumably, FIFO is not half-full) we should write *two*
1463 	 * packets before updating TXCSR; other docs disagree...
1464 	 */
1465 	if (length > qh->maxpacket)
1466 		length = qh->maxpacket;
1467 	/* Unmap the buffer so that CPU can use it */
1468 	usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1469 
1470 	/*
1471 	 * We need to map sg if the transfer_buffer is
1472 	 * NULL.
1473 	 */
1474 	if (!urb->transfer_buffer)
1475 		qh->use_sg = true;
1476 
1477 	if (qh->use_sg) {
1478 		/* sg_miter_start is already done in musb_ep_program */
1479 		if (!sg_miter_next(&qh->sg_miter)) {
1480 			dev_err(musb->controller, "error: sg list empty\n");
1481 			sg_miter_stop(&qh->sg_miter);
1482 			status = -EINVAL;
1483 			goto done;
1484 		}
1485 		urb->transfer_buffer = qh->sg_miter.addr;
1486 		length = min_t(u32, length, qh->sg_miter.length);
1487 		musb_write_fifo(hw_ep, length, urb->transfer_buffer);
1488 		qh->sg_miter.consumed = length;
1489 		sg_miter_stop(&qh->sg_miter);
1490 	} else {
1491 		musb_write_fifo(hw_ep, length, urb->transfer_buffer + offset);
1492 	}
1493 
1494 	qh->segsize = length;
1495 
1496 	if (qh->use_sg) {
1497 		if (offset + length >= urb->transfer_buffer_length)
1498 			qh->use_sg = false;
1499 	}
1500 
1501 	musb_ep_select(mbase, epnum);
1502 	musb_writew(epio, MUSB_TXCSR,
1503 			MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
1504 }
1505 
1506 
1507 #ifdef CONFIG_USB_INVENTRA_DMA
1508 
1509 /* Host side RX (IN) using Mentor DMA works as follows:
1510 	submit_urb ->
1511 		- if queue was empty, ProgramEndpoint
1512 		- first IN token is sent out (by setting ReqPkt)
1513 	LinuxIsr -> RxReady()
1514 	/\	=> first packet is received
1515 	|	- Set in mode 0 (DmaEnab, ~ReqPkt)
1516 	|		-> DMA Isr (transfer complete) -> RxReady()
1517 	|		    - Ack receive (~RxPktRdy), turn off DMA (~DmaEnab)
1518 	|		    - if urb not complete, send next IN token (ReqPkt)
1519 	|			   |		else complete urb.
1520 	|			   |
1521 	---------------------------
1522  *
1523  * Nuances of mode 1:
1524  *	For short packets, no ack (+RxPktRdy) is sent automatically
1525  *	(even if AutoClear is ON)
1526  *	For full packets, ack (~RxPktRdy) and next IN token (+ReqPkt) is sent
1527  *	automatically => major problem, as collecting the next packet becomes
1528  *	difficult. Hence mode 1 is not used.
1529  *
1530  * REVISIT
1531  *	All we care about at this driver level is that
1532  *       (a) all URBs terminate with REQPKT cleared and fifo(s) empty;
1533  *       (b) termination conditions are: short RX, or buffer full;
1534  *       (c) fault modes include
1535  *           - iff URB_SHORT_NOT_OK, short RX status is -EREMOTEIO.
1536  *             (and that endpoint's dma queue stops immediately)
1537  *           - overflow (full, PLUS more bytes in the terminal packet)
1538  *
1539  *	So for example, usb-storage sets URB_SHORT_NOT_OK, and would
1540  *	thus be a great candidate for using mode 1 ... for all but the
1541  *	last packet of one URB's transfer.
1542  */
1543 
1544 #endif
1545 
1546 /*
1547  * Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
1548  * and high-bandwidth IN transfer cases.
1549  */
musb_host_rx(struct musb * musb,u8 epnum)1550 void musb_host_rx(struct musb *musb, u8 epnum)
1551 {
1552 	struct urb		*urb;
1553 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1554 	void __iomem		*epio = hw_ep->regs;
1555 	struct musb_qh		*qh = hw_ep->in_qh;
1556 	size_t			xfer_len;
1557 	void __iomem		*mbase = musb->mregs;
1558 	int			pipe;
1559 	u16			rx_csr, val;
1560 	bool			iso_err = false;
1561 	bool			done = false;
1562 	u32			status;
1563 	struct dma_channel	*dma;
1564 	unsigned int sg_flags = SG_MITER_ATOMIC | SG_MITER_TO_SG;
1565 
1566 	musb_ep_select(mbase, epnum);
1567 
1568 	urb = next_urb(qh);
1569 	dma = is_dma_capable() ? hw_ep->rx_channel : NULL;
1570 	status = 0;
1571 	xfer_len = 0;
1572 
1573 	rx_csr = musb_readw(epio, MUSB_RXCSR);
1574 	val = rx_csr;
1575 
1576 	if (unlikely(!urb)) {
1577 		/* REVISIT -- THIS SHOULD NEVER HAPPEN ... but, at least
1578 		 * usbtest #11 (unlinks) triggers it regularly, sometimes
1579 		 * with fifo full.  (Only with DMA??)
1580 		 */
1581 		dev_dbg(musb->controller, "BOGUS RX%d ready, csr %04x, count %d\n", epnum, val,
1582 			musb_readw(epio, MUSB_RXCOUNT));
1583 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1584 		return;
1585 	}
1586 
1587 	pipe = urb->pipe;
1588 
1589 	dev_dbg(musb->controller, "<== hw %d rxcsr %04x, urb actual %d (+dma %zu)\n",
1590 		epnum, rx_csr, urb->actual_length,
1591 		dma ? dma->actual_len : 0);
1592 
1593 	/* check for errors, concurrent stall & unlink is not really
1594 	 * handled yet! */
1595 	if (rx_csr & MUSB_RXCSR_H_RXSTALL) {
1596 		dev_dbg(musb->controller, "RX end %d STALL\n", epnum);
1597 
1598 		/* stall; record URB status */
1599 		status = -EPIPE;
1600 
1601 	} else if (rx_csr & MUSB_RXCSR_H_ERROR) {
1602 		dev_dbg(musb->controller, "end %d RX proto error\n", epnum);
1603 
1604 		status = -EPROTO;
1605 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1606 
1607 	} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
1608 
1609 		if (USB_ENDPOINT_XFER_ISOC != qh->type) {
1610 			dev_dbg(musb->controller, "RX end %d NAK timeout\n", epnum);
1611 
1612 			/* NOTE: NAKing is *NOT* an error, so we want to
1613 			 * continue.  Except ... if there's a request for
1614 			 * another QH, use that instead of starving it.
1615 			 *
1616 			 * Devices like Ethernet and serial adapters keep
1617 			 * reads posted at all times, which will starve
1618 			 * other devices without this logic.
1619 			 */
1620 			if (usb_pipebulk(urb->pipe)
1621 					&& qh->mux == 1
1622 					&& !list_is_singular(&musb->in_bulk)) {
1623 				musb_bulk_nak_timeout(musb, hw_ep, 1);
1624 				return;
1625 			}
1626 			musb_ep_select(mbase, epnum);
1627 			rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1628 			rx_csr &= ~MUSB_RXCSR_DATAERROR;
1629 			musb_writew(epio, MUSB_RXCSR, rx_csr);
1630 
1631 			goto finish;
1632 		} else {
1633 			dev_dbg(musb->controller, "RX end %d ISO data error\n", epnum);
1634 			/* packet error reported later */
1635 			iso_err = true;
1636 		}
1637 	} else if (rx_csr & MUSB_RXCSR_INCOMPRX) {
1638 		dev_dbg(musb->controller, "end %d high bandwidth incomplete ISO packet RX\n",
1639 				epnum);
1640 		status = -EPROTO;
1641 	}
1642 
1643 	/* faults abort the transfer */
1644 	if (status) {
1645 		/* clean up dma and collect transfer count */
1646 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1647 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1648 			musb->dma_controller->channel_abort(dma);
1649 			xfer_len = dma->actual_len;
1650 		}
1651 		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1652 		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1653 		done = true;
1654 		goto finish;
1655 	}
1656 
1657 	if (unlikely(dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY)) {
1658 		/* SHOULD NEVER HAPPEN ... but at least DaVinci has done it */
1659 		ERR("RX%d dma busy, csr %04x\n", epnum, rx_csr);
1660 		goto finish;
1661 	}
1662 
1663 	/* thorough shutdown for now ... given more precise fault handling
1664 	 * and better queueing support, we might keep a DMA pipeline going
1665 	 * while processing this irq for earlier completions.
1666 	 */
1667 
1668 	/* FIXME this is _way_ too much in-line logic for Mentor DMA */
1669 
1670 #if !defined(CONFIG_USB_INVENTRA_DMA) && !defined(CONFIG_USB_UX500_DMA)
1671 	if (rx_csr & MUSB_RXCSR_H_REQPKT)  {
1672 		/* REVISIT this happened for a while on some short reads...
1673 		 * the cleanup still needs investigation... looks bad...
1674 		 * and also duplicates dma cleanup code above ... plus,
1675 		 * shouldn't this be the "half full" double buffer case?
1676 		 */
1677 		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1678 			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1679 			musb->dma_controller->channel_abort(dma);
1680 			xfer_len = dma->actual_len;
1681 			done = true;
1682 		}
1683 
1684 		dev_dbg(musb->controller, "RXCSR%d %04x, reqpkt, len %zu%s\n", epnum, rx_csr,
1685 				xfer_len, dma ? ", dma" : "");
1686 		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
1687 
1688 		musb_ep_select(mbase, epnum);
1689 		musb_writew(epio, MUSB_RXCSR,
1690 				MUSB_RXCSR_H_WZC_BITS | rx_csr);
1691 	}
1692 #endif
1693 	if (dma && (rx_csr & MUSB_RXCSR_DMAENAB)) {
1694 		xfer_len = dma->actual_len;
1695 
1696 		val &= ~(MUSB_RXCSR_DMAENAB
1697 			| MUSB_RXCSR_H_AUTOREQ
1698 			| MUSB_RXCSR_AUTOCLEAR
1699 			| MUSB_RXCSR_RXPKTRDY);
1700 		musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1701 
1702 #if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA) || \
1703 	defined(CONFIG_USB_TI_CPPI41_DMA)
1704 		if (usb_pipeisoc(pipe)) {
1705 			struct usb_iso_packet_descriptor *d;
1706 
1707 			d = urb->iso_frame_desc + qh->iso_idx;
1708 			d->actual_length = xfer_len;
1709 
1710 			/* even if there was an error, we did the dma
1711 			 * for iso_frame_desc->length
1712 			 */
1713 			if (d->status != -EILSEQ && d->status != -EOVERFLOW)
1714 				d->status = 0;
1715 
1716 			if (++qh->iso_idx >= urb->number_of_packets) {
1717 				done = true;
1718 			} else {
1719 #if defined(CONFIG_USB_TI_CPPI41_DMA)
1720 				struct dma_controller   *c;
1721 				dma_addr_t *buf;
1722 				u32 length, ret;
1723 
1724 				c = musb->dma_controller;
1725 				buf = (void *)
1726 					urb->iso_frame_desc[qh->iso_idx].offset
1727 					+ (u32)urb->transfer_dma;
1728 
1729 				length =
1730 					urb->iso_frame_desc[qh->iso_idx].length;
1731 
1732 				val |= MUSB_RXCSR_DMAENAB;
1733 				musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1734 
1735 				ret = c->channel_program(dma, qh->maxpacket,
1736 						0, (u32) buf, length);
1737 #endif
1738 				done = false;
1739 			}
1740 
1741 		} else  {
1742 			/* done if urb buffer is full or short packet is recd */
1743 			done = (urb->actual_length + xfer_len >=
1744 					urb->transfer_buffer_length
1745 				|| dma->actual_len < qh->maxpacket
1746 				|| dma->rx_packet_done);
1747 		}
1748 
1749 		/* send IN token for next packet, without AUTOREQ */
1750 		if (!done) {
1751 			val |= MUSB_RXCSR_H_REQPKT;
1752 			musb_writew(epio, MUSB_RXCSR,
1753 				MUSB_RXCSR_H_WZC_BITS | val);
1754 		}
1755 
1756 		dev_dbg(musb->controller, "ep %d dma %s, rxcsr %04x, rxcount %d\n", epnum,
1757 			done ? "off" : "reset",
1758 			musb_readw(epio, MUSB_RXCSR),
1759 			musb_readw(epio, MUSB_RXCOUNT));
1760 #else
1761 		done = true;
1762 #endif
1763 	} else if (urb->status == -EINPROGRESS) {
1764 		/* if no errors, be sure a packet is ready for unloading */
1765 		if (unlikely(!(rx_csr & MUSB_RXCSR_RXPKTRDY))) {
1766 			status = -EPROTO;
1767 			ERR("Rx interrupt with no errors or packet!\n");
1768 
1769 			/* FIXME this is another "SHOULD NEVER HAPPEN" */
1770 
1771 /* SCRUB (RX) */
1772 			/* do the proper sequence to abort the transfer */
1773 			musb_ep_select(mbase, epnum);
1774 			val &= ~MUSB_RXCSR_H_REQPKT;
1775 			musb_writew(epio, MUSB_RXCSR, val);
1776 			goto finish;
1777 		}
1778 
1779 		/* we are expecting IN packets */
1780 #if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA) || \
1781 	defined(CONFIG_USB_TI_CPPI41_DMA)
1782 		if (dma) {
1783 			struct dma_controller	*c;
1784 			u16			rx_count;
1785 			int			ret, length;
1786 			dma_addr_t		buf;
1787 
1788 			rx_count = musb_readw(epio, MUSB_RXCOUNT);
1789 
1790 			dev_dbg(musb->controller, "RX%d count %d, buffer 0x%llx len %d/%d\n",
1791 					epnum, rx_count,
1792 					(unsigned long long) urb->transfer_dma
1793 					+ urb->actual_length,
1794 					qh->offset,
1795 					urb->transfer_buffer_length);
1796 
1797 			c = musb->dma_controller;
1798 
1799 			if (usb_pipeisoc(pipe)) {
1800 				int d_status = 0;
1801 				struct usb_iso_packet_descriptor *d;
1802 
1803 				d = urb->iso_frame_desc + qh->iso_idx;
1804 
1805 				if (iso_err) {
1806 					d_status = -EILSEQ;
1807 					urb->error_count++;
1808 				}
1809 				if (rx_count > d->length) {
1810 					if (d_status == 0) {
1811 						d_status = -EOVERFLOW;
1812 						urb->error_count++;
1813 					}
1814 					dev_dbg(musb->controller, "** OVERFLOW %d into %d\n",\
1815 					    rx_count, d->length);
1816 
1817 					length = d->length;
1818 				} else
1819 					length = rx_count;
1820 				d->status = d_status;
1821 				buf = urb->transfer_dma + d->offset;
1822 			} else {
1823 				length = rx_count;
1824 				buf = urb->transfer_dma +
1825 						urb->actual_length;
1826 			}
1827 
1828 			dma->desired_mode = 0;
1829 #ifdef USE_MODE1
1830 			/* because of the issue below, mode 1 will
1831 			 * only rarely behave with correct semantics.
1832 			 */
1833 			if ((urb->transfer_flags &
1834 						URB_SHORT_NOT_OK)
1835 				&& (urb->transfer_buffer_length -
1836 						urb->actual_length)
1837 					> qh->maxpacket)
1838 				dma->desired_mode = 1;
1839 			if (rx_count < hw_ep->max_packet_sz_rx) {
1840 				length = rx_count;
1841 				dma->desired_mode = 0;
1842 			} else {
1843 				length = urb->transfer_buffer_length;
1844 			}
1845 #endif
1846 
1847 /* Disadvantage of using mode 1:
1848  *	It's basically usable only for mass storage class; essentially all
1849  *	other protocols also terminate transfers on short packets.
1850  *
1851  * Details:
1852  *	An extra IN token is sent at the end of the transfer (due to AUTOREQ)
1853  *	If you try to use mode 1 for (transfer_buffer_length - 512), and try
1854  *	to use the extra IN token to grab the last packet using mode 0, then
1855  *	the problem is that you cannot be sure when the device will send the
1856  *	last packet and RxPktRdy set. Sometimes the packet is recd too soon
1857  *	such that it gets lost when RxCSR is re-set at the end of the mode 1
1858  *	transfer, while sometimes it is recd just a little late so that if you
1859  *	try to configure for mode 0 soon after the mode 1 transfer is
1860  *	completed, you will find rxcount 0. Okay, so you might think why not
1861  *	wait for an interrupt when the pkt is recd. Well, you won't get any!
1862  */
1863 
1864 			val = musb_readw(epio, MUSB_RXCSR);
1865 			val &= ~MUSB_RXCSR_H_REQPKT;
1866 
1867 			if (dma->desired_mode == 0)
1868 				val &= ~MUSB_RXCSR_H_AUTOREQ;
1869 			else
1870 				val |= MUSB_RXCSR_H_AUTOREQ;
1871 			val |= MUSB_RXCSR_DMAENAB;
1872 
1873 			/* autoclear shouldn't be set in high bandwidth */
1874 			if (qh->hb_mult == 1)
1875 				val |= MUSB_RXCSR_AUTOCLEAR;
1876 
1877 			musb_writew(epio, MUSB_RXCSR,
1878 				MUSB_RXCSR_H_WZC_BITS | val);
1879 
1880 			/* REVISIT if when actual_length != 0,
1881 			 * transfer_buffer_length needs to be
1882 			 * adjusted first...
1883 			 */
1884 			ret = c->channel_program(
1885 				dma, qh->maxpacket,
1886 				dma->desired_mode, buf, length);
1887 
1888 			if (!ret) {
1889 				c->channel_release(dma);
1890 				hw_ep->rx_channel = NULL;
1891 				dma = NULL;
1892 				val = musb_readw(epio, MUSB_RXCSR);
1893 				val &= ~(MUSB_RXCSR_DMAENAB
1894 					| MUSB_RXCSR_H_AUTOREQ
1895 					| MUSB_RXCSR_AUTOCLEAR);
1896 				musb_writew(epio, MUSB_RXCSR, val);
1897 			}
1898 		}
1899 #endif	/* Mentor DMA */
1900 
1901 		if (!dma) {
1902 			unsigned int received_len;
1903 
1904 			/* Unmap the buffer so that CPU can use it */
1905 			usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1906 
1907 			/*
1908 			 * We need to map sg if the transfer_buffer is
1909 			 * NULL.
1910 			 */
1911 			if (!urb->transfer_buffer) {
1912 				qh->use_sg = true;
1913 				sg_miter_start(&qh->sg_miter, urb->sg, 1,
1914 						sg_flags);
1915 			}
1916 
1917 			if (qh->use_sg) {
1918 				if (!sg_miter_next(&qh->sg_miter)) {
1919 					dev_err(musb->controller, "error: sg list empty\n");
1920 					sg_miter_stop(&qh->sg_miter);
1921 					status = -EINVAL;
1922 					done = true;
1923 					goto finish;
1924 				}
1925 				urb->transfer_buffer = qh->sg_miter.addr;
1926 				received_len = urb->actual_length;
1927 				qh->offset = 0x0;
1928 				done = musb_host_packet_rx(musb, urb, epnum,
1929 						iso_err);
1930 				/* Calculate the number of bytes received */
1931 				received_len = urb->actual_length -
1932 					received_len;
1933 				qh->sg_miter.consumed = received_len;
1934 				sg_miter_stop(&qh->sg_miter);
1935 			} else {
1936 				done = musb_host_packet_rx(musb, urb,
1937 						epnum, iso_err);
1938 			}
1939 			dev_dbg(musb->controller, "read %spacket\n", done ? "last " : "");
1940 		}
1941 	}
1942 
1943 finish:
1944 	urb->actual_length += xfer_len;
1945 	qh->offset += xfer_len;
1946 	if (done) {
1947 		if (qh->use_sg)
1948 			qh->use_sg = false;
1949 
1950 		if (urb->status == -EINPROGRESS)
1951 			urb->status = status;
1952 		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_IN);
1953 	}
1954 }
1955 
1956 /* schedule nodes correspond to peripheral endpoints, like an OHCI QH.
1957  * the software schedule associates multiple such nodes with a given
1958  * host side hardware endpoint + direction; scheduling may activate
1959  * that hardware endpoint.
1960  */
musb_schedule(struct musb * musb,struct musb_qh * qh,int is_in)1961 static int musb_schedule(
1962 	struct musb		*musb,
1963 	struct musb_qh		*qh,
1964 	int			is_in)
1965 {
1966 	int			idle = 0;
1967 	int			best_diff;
1968 	int			best_end, epnum;
1969 	struct musb_hw_ep	*hw_ep = NULL;
1970 	struct list_head	*head = NULL;
1971 	u8			toggle;
1972 	u8			txtype;
1973 	struct urb		*urb = next_urb(qh);
1974 
1975 	/* use fixed hardware for control and bulk */
1976 	if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
1977 		head = &musb->control;
1978 		hw_ep = musb->control_ep;
1979 		goto success;
1980 	}
1981 
1982 	/* else, periodic transfers get muxed to other endpoints */
1983 
1984 	/*
1985 	 * We know this qh hasn't been scheduled, so all we need to do
1986 	 * is choose which hardware endpoint to put it on ...
1987 	 *
1988 	 * REVISIT what we really want here is a regular schedule tree
1989 	 * like e.g. OHCI uses.
1990 	 */
1991 	best_diff = 4096;
1992 	best_end = -1;
1993 
1994 	for (epnum = 1, hw_ep = musb->endpoints + 1;
1995 			epnum < musb->nr_endpoints;
1996 			epnum++, hw_ep++) {
1997 		int	diff;
1998 
1999 		if (musb_ep_get_qh(hw_ep, is_in) != NULL)
2000 			continue;
2001 
2002 		if (hw_ep == musb->bulk_ep)
2003 			continue;
2004 
2005 		if (is_in)
2006 			diff = hw_ep->max_packet_sz_rx;
2007 		else
2008 			diff = hw_ep->max_packet_sz_tx;
2009 		diff -= (qh->maxpacket * qh->hb_mult);
2010 
2011 		if (diff >= 0 && best_diff > diff) {
2012 
2013 			/*
2014 			 * Mentor controller has a bug in that if we schedule
2015 			 * a BULK Tx transfer on an endpoint that had earlier
2016 			 * handled ISOC then the BULK transfer has to start on
2017 			 * a zero toggle.  If the BULK transfer starts on a 1
2018 			 * toggle then this transfer will fail as the mentor
2019 			 * controller starts the Bulk transfer on a 0 toggle
2020 			 * irrespective of the programming of the toggle bits
2021 			 * in the TXCSR register.  Check for this condition
2022 			 * while allocating the EP for a Tx Bulk transfer.  If
2023 			 * so skip this EP.
2024 			 */
2025 			hw_ep = musb->endpoints + epnum;
2026 			toggle = usb_gettoggle(urb->dev, qh->epnum, !is_in);
2027 			txtype = (musb_readb(hw_ep->regs, MUSB_TXTYPE)
2028 					>> 4) & 0x3;
2029 			if (!is_in && (qh->type == USB_ENDPOINT_XFER_BULK) &&
2030 				toggle && (txtype == USB_ENDPOINT_XFER_ISOC))
2031 				continue;
2032 
2033 			best_diff = diff;
2034 			best_end = epnum;
2035 		}
2036 	}
2037 	/* use bulk reserved ep1 if no other ep is free */
2038 	if (best_end < 0 && qh->type == USB_ENDPOINT_XFER_BULK) {
2039 		hw_ep = musb->bulk_ep;
2040 		if (is_in)
2041 			head = &musb->in_bulk;
2042 		else
2043 			head = &musb->out_bulk;
2044 
2045 		/* Enable bulk RX/TX NAK timeout scheme when bulk requests are
2046 		 * multiplexed. This scheme does not work in high speed to full
2047 		 * speed scenario as NAK interrupts are not coming from a
2048 		 * full speed device connected to a high speed device.
2049 		 * NAK timeout interval is 8 (128 uframe or 16ms) for HS and
2050 		 * 4 (8 frame or 8ms) for FS device.
2051 		 */
2052 		if (qh->dev)
2053 			qh->intv_reg =
2054 				(USB_SPEED_HIGH == qh->dev->speed) ? 8 : 4;
2055 		goto success;
2056 	} else if (best_end < 0) {
2057 		return -ENOSPC;
2058 	}
2059 
2060 	idle = 1;
2061 	qh->mux = 0;
2062 	hw_ep = musb->endpoints + best_end;
2063 	dev_dbg(musb->controller, "qh %p periodic slot %d\n", qh, best_end);
2064 success:
2065 	if (head) {
2066 		idle = list_empty(head);
2067 		list_add_tail(&qh->ring, head);
2068 		qh->mux = 1;
2069 	}
2070 	qh->hw_ep = hw_ep;
2071 	qh->hep->hcpriv = qh;
2072 	if (idle)
2073 		musb_start_urb(musb, is_in, qh);
2074 	return 0;
2075 }
2076 
musb_urb_enqueue(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)2077 static int musb_urb_enqueue(
2078 	struct usb_hcd			*hcd,
2079 	struct urb			*urb,
2080 	gfp_t				mem_flags)
2081 {
2082 	unsigned long			flags;
2083 	struct musb			*musb = hcd_to_musb(hcd);
2084 	struct usb_host_endpoint	*hep = urb->ep;
2085 	struct musb_qh			*qh;
2086 	struct usb_endpoint_descriptor	*epd = &hep->desc;
2087 	int				ret;
2088 	unsigned			type_reg;
2089 	unsigned			interval;
2090 
2091 	/* host role must be active */
2092 	if (!is_host_active(musb) || !musb->is_active)
2093 		return -ENODEV;
2094 
2095 	spin_lock_irqsave(&musb->lock, flags);
2096 	ret = usb_hcd_link_urb_to_ep(hcd, urb);
2097 	qh = ret ? NULL : hep->hcpriv;
2098 	if (qh)
2099 		urb->hcpriv = qh;
2100 	spin_unlock_irqrestore(&musb->lock, flags);
2101 
2102 	/* DMA mapping was already done, if needed, and this urb is on
2103 	 * hep->urb_list now ... so we're done, unless hep wasn't yet
2104 	 * scheduled onto a live qh.
2105 	 *
2106 	 * REVISIT best to keep hep->hcpriv valid until the endpoint gets
2107 	 * disabled, testing for empty qh->ring and avoiding qh setup costs
2108 	 * except for the first urb queued after a config change.
2109 	 */
2110 	if (qh || ret)
2111 		return ret;
2112 
2113 	/* Allocate and initialize qh, minimizing the work done each time
2114 	 * hw_ep gets reprogrammed, or with irqs blocked.  Then schedule it.
2115 	 *
2116 	 * REVISIT consider a dedicated qh kmem_cache, so it's harder
2117 	 * for bugs in other kernel code to break this driver...
2118 	 */
2119 	qh = kzalloc(sizeof *qh, mem_flags);
2120 	if (!qh) {
2121 		spin_lock_irqsave(&musb->lock, flags);
2122 		usb_hcd_unlink_urb_from_ep(hcd, urb);
2123 		spin_unlock_irqrestore(&musb->lock, flags);
2124 		return -ENOMEM;
2125 	}
2126 
2127 	qh->hep = hep;
2128 	qh->dev = urb->dev;
2129 	INIT_LIST_HEAD(&qh->ring);
2130 	qh->is_ready = 1;
2131 
2132 	qh->maxpacket = usb_endpoint_maxp(epd);
2133 	qh->type = usb_endpoint_type(epd);
2134 
2135 	/* Bits 11 & 12 of wMaxPacketSize encode high bandwidth multiplier.
2136 	 * Some musb cores don't support high bandwidth ISO transfers; and
2137 	 * we don't (yet!) support high bandwidth interrupt transfers.
2138 	 */
2139 	qh->hb_mult = 1 + ((qh->maxpacket >> 11) & 0x03);
2140 	if (qh->hb_mult > 1) {
2141 		int ok = (qh->type == USB_ENDPOINT_XFER_ISOC);
2142 
2143 		if (ok)
2144 			ok = (usb_pipein(urb->pipe) && musb->hb_iso_rx)
2145 				|| (usb_pipeout(urb->pipe) && musb->hb_iso_tx);
2146 		if (!ok) {
2147 			ret = -EMSGSIZE;
2148 			goto done;
2149 		}
2150 		qh->maxpacket &= 0x7ff;
2151 	}
2152 
2153 	qh->epnum = usb_endpoint_num(epd);
2154 
2155 	/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
2156 	qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
2157 
2158 	/* precompute rxtype/txtype/type0 register */
2159 	type_reg = (qh->type << 4) | qh->epnum;
2160 	switch (urb->dev->speed) {
2161 	case USB_SPEED_LOW:
2162 		type_reg |= 0xc0;
2163 		break;
2164 	case USB_SPEED_FULL:
2165 		type_reg |= 0x80;
2166 		break;
2167 	default:
2168 		type_reg |= 0x40;
2169 	}
2170 	qh->type_reg = type_reg;
2171 
2172 	/* Precompute RXINTERVAL/TXINTERVAL register */
2173 	switch (qh->type) {
2174 	case USB_ENDPOINT_XFER_INT:
2175 		/*
2176 		 * Full/low speeds use the  linear encoding,
2177 		 * high speed uses the logarithmic encoding.
2178 		 */
2179 		if (urb->dev->speed <= USB_SPEED_FULL) {
2180 			interval = max_t(u8, epd->bInterval, 1);
2181 			break;
2182 		}
2183 		/* FALLTHROUGH */
2184 	case USB_ENDPOINT_XFER_ISOC:
2185 		/* ISO always uses logarithmic encoding */
2186 		interval = min_t(u8, epd->bInterval, 16);
2187 		break;
2188 	default:
2189 		/* REVISIT we actually want to use NAK limits, hinting to the
2190 		 * transfer scheduling logic to try some other qh, e.g. try
2191 		 * for 2 msec first:
2192 		 *
2193 		 * interval = (USB_SPEED_HIGH == urb->dev->speed) ? 16 : 2;
2194 		 *
2195 		 * The downside of disabling this is that transfer scheduling
2196 		 * gets VERY unfair for nonperiodic transfers; a misbehaving
2197 		 * peripheral could make that hurt.  That's perfectly normal
2198 		 * for reads from network or serial adapters ... so we have
2199 		 * partial NAKlimit support for bulk RX.
2200 		 *
2201 		 * The upside of disabling it is simpler transfer scheduling.
2202 		 */
2203 		interval = 0;
2204 	}
2205 	qh->intv_reg = interval;
2206 
2207 	/* precompute addressing for external hub/tt ports */
2208 	if (musb->is_multipoint) {
2209 		struct usb_device	*parent = urb->dev->parent;
2210 
2211 		if (parent != hcd->self.root_hub) {
2212 			qh->h_addr_reg = (u8) parent->devnum;
2213 
2214 			/* set up tt info if needed */
2215 			if (urb->dev->tt) {
2216 				qh->h_port_reg = (u8) urb->dev->ttport;
2217 				if (urb->dev->tt->hub)
2218 					qh->h_addr_reg =
2219 						(u8) urb->dev->tt->hub->devnum;
2220 				if (urb->dev->tt->multi)
2221 					qh->h_addr_reg |= 0x80;
2222 			}
2223 		}
2224 	}
2225 
2226 	/* invariant: hep->hcpriv is null OR the qh that's already scheduled.
2227 	 * until we get real dma queues (with an entry for each urb/buffer),
2228 	 * we only have work to do in the former case.
2229 	 */
2230 	spin_lock_irqsave(&musb->lock, flags);
2231 	if (hep->hcpriv || !next_urb(qh)) {
2232 		/* some concurrent activity submitted another urb to hep...
2233 		 * odd, rare, error prone, but legal.
2234 		 */
2235 		kfree(qh);
2236 		qh = NULL;
2237 		ret = 0;
2238 	} else
2239 		ret = musb_schedule(musb, qh,
2240 				epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK);
2241 
2242 	if (ret == 0) {
2243 		urb->hcpriv = qh;
2244 		/* FIXME set urb->start_frame for iso/intr, it's tested in
2245 		 * musb_start_urb(), but otherwise only konicawc cares ...
2246 		 */
2247 	}
2248 	spin_unlock_irqrestore(&musb->lock, flags);
2249 
2250 done:
2251 	if (ret != 0) {
2252 		spin_lock_irqsave(&musb->lock, flags);
2253 		usb_hcd_unlink_urb_from_ep(hcd, urb);
2254 		spin_unlock_irqrestore(&musb->lock, flags);
2255 		kfree(qh);
2256 	}
2257 	return ret;
2258 }
2259 
2260 
2261 /*
2262  * abort a transfer that's at the head of a hardware queue.
2263  * called with controller locked, irqs blocked
2264  * that hardware queue advances to the next transfer, unless prevented
2265  */
musb_cleanup_urb(struct urb * urb,struct musb_qh * qh)2266 static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh)
2267 {
2268 	struct musb_hw_ep	*ep = qh->hw_ep;
2269 	struct musb		*musb = ep->musb;
2270 	void __iomem		*epio = ep->regs;
2271 	unsigned		hw_end = ep->epnum;
2272 	void __iomem		*regs = ep->musb->mregs;
2273 	int			is_in = usb_pipein(urb->pipe);
2274 	int			status = 0;
2275 	u16			csr;
2276 
2277 	musb_ep_select(regs, hw_end);
2278 
2279 	if (is_dma_capable()) {
2280 		struct dma_channel	*dma;
2281 
2282 		dma = is_in ? ep->rx_channel : ep->tx_channel;
2283 		if (dma) {
2284 			status = ep->musb->dma_controller->channel_abort(dma);
2285 			dev_dbg(musb->controller,
2286 				"abort %cX%d DMA for urb %p --> %d\n",
2287 				is_in ? 'R' : 'T', ep->epnum,
2288 				urb, status);
2289 			urb->actual_length += dma->actual_len;
2290 		}
2291 	}
2292 
2293 	/* turn off DMA requests, discard state, stop polling ... */
2294 	if (ep->epnum && is_in) {
2295 		/* giveback saves bulk toggle */
2296 		csr = musb_h_flush_rxfifo(ep, 0);
2297 
2298 		/* REVISIT we still get an irq; should likely clear the
2299 		 * endpoint's irq status here to avoid bogus irqs.
2300 		 * clearing that status is platform-specific...
2301 		 */
2302 	} else if (ep->epnum) {
2303 		musb_h_tx_flush_fifo(ep);
2304 		csr = musb_readw(epio, MUSB_TXCSR);
2305 		csr &= ~(MUSB_TXCSR_AUTOSET
2306 			| MUSB_TXCSR_DMAENAB
2307 			| MUSB_TXCSR_H_RXSTALL
2308 			| MUSB_TXCSR_H_NAKTIMEOUT
2309 			| MUSB_TXCSR_H_ERROR
2310 			| MUSB_TXCSR_TXPKTRDY);
2311 		musb_writew(epio, MUSB_TXCSR, csr);
2312 		/* REVISIT may need to clear FLUSHFIFO ... */
2313 		musb_writew(epio, MUSB_TXCSR, csr);
2314 		/* flush cpu writebuffer */
2315 		csr = musb_readw(epio, MUSB_TXCSR);
2316 	} else  {
2317 		musb_h_ep0_flush_fifo(ep);
2318 	}
2319 	if (status == 0)
2320 		musb_advance_schedule(ep->musb, urb, ep, is_in);
2321 	return status;
2322 }
2323 
musb_urb_dequeue(struct usb_hcd * hcd,struct urb * urb,int status)2324 static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
2325 {
2326 	struct musb		*musb = hcd_to_musb(hcd);
2327 	struct musb_qh		*qh;
2328 	unsigned long		flags;
2329 	int			is_in  = usb_pipein(urb->pipe);
2330 	int			ret;
2331 
2332 	dev_dbg(musb->controller, "urb=%p, dev%d ep%d%s\n", urb,
2333 			usb_pipedevice(urb->pipe),
2334 			usb_pipeendpoint(urb->pipe),
2335 			is_in ? "in" : "out");
2336 
2337 	spin_lock_irqsave(&musb->lock, flags);
2338 	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
2339 	if (ret)
2340 		goto done;
2341 
2342 	qh = urb->hcpriv;
2343 	if (!qh)
2344 		goto done;
2345 
2346 	/*
2347 	 * Any URB not actively programmed into endpoint hardware can be
2348 	 * immediately given back; that's any URB not at the head of an
2349 	 * endpoint queue, unless someday we get real DMA queues.  And even
2350 	 * if it's at the head, it might not be known to the hardware...
2351 	 *
2352 	 * Otherwise abort current transfer, pending DMA, etc.; urb->status
2353 	 * has already been updated.  This is a synchronous abort; it'd be
2354 	 * OK to hold off until after some IRQ, though.
2355 	 *
2356 	 * NOTE: qh is invalid unless !list_empty(&hep->urb_list)
2357 	 */
2358 	if (!qh->is_ready
2359 			|| urb->urb_list.prev != &qh->hep->urb_list
2360 			|| musb_ep_get_qh(qh->hw_ep, is_in) != qh) {
2361 		int	ready = qh->is_ready;
2362 
2363 		qh->is_ready = 0;
2364 		musb_giveback(musb, urb, 0);
2365 		qh->is_ready = ready;
2366 
2367 		/* If nothing else (usually musb_giveback) is using it
2368 		 * and its URB list has emptied, recycle this qh.
2369 		 */
2370 		if (ready && list_empty(&qh->hep->urb_list)) {
2371 			qh->hep->hcpriv = NULL;
2372 			list_del(&qh->ring);
2373 			kfree(qh);
2374 		}
2375 	} else
2376 		ret = musb_cleanup_urb(urb, qh);
2377 done:
2378 	spin_unlock_irqrestore(&musb->lock, flags);
2379 	return ret;
2380 }
2381 
2382 /* disable an endpoint */
2383 static void
musb_h_disable(struct usb_hcd * hcd,struct usb_host_endpoint * hep)2384 musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
2385 {
2386 	u8			is_in = hep->desc.bEndpointAddress & USB_DIR_IN;
2387 	unsigned long		flags;
2388 	struct musb		*musb = hcd_to_musb(hcd);
2389 	struct musb_qh		*qh;
2390 	struct urb		*urb;
2391 
2392 	spin_lock_irqsave(&musb->lock, flags);
2393 
2394 	qh = hep->hcpriv;
2395 	if (qh == NULL)
2396 		goto exit;
2397 
2398 	/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
2399 
2400 	/* Kick the first URB off the hardware, if needed */
2401 	qh->is_ready = 0;
2402 	if (musb_ep_get_qh(qh->hw_ep, is_in) == qh) {
2403 		urb = next_urb(qh);
2404 
2405 		/* make software (then hardware) stop ASAP */
2406 		if (!urb->unlinked)
2407 			urb->status = -ESHUTDOWN;
2408 
2409 		/* cleanup */
2410 		musb_cleanup_urb(urb, qh);
2411 
2412 		/* Then nuke all the others ... and advance the
2413 		 * queue on hw_ep (e.g. bulk ring) when we're done.
2414 		 */
2415 		while (!list_empty(&hep->urb_list)) {
2416 			urb = next_urb(qh);
2417 			urb->status = -ESHUTDOWN;
2418 			musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
2419 		}
2420 	} else {
2421 		/* Just empty the queue; the hardware is busy with
2422 		 * other transfers, and since !qh->is_ready nothing
2423 		 * will activate any of these as it advances.
2424 		 */
2425 		while (!list_empty(&hep->urb_list))
2426 			musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
2427 
2428 		hep->hcpriv = NULL;
2429 		list_del(&qh->ring);
2430 		kfree(qh);
2431 	}
2432 exit:
2433 	spin_unlock_irqrestore(&musb->lock, flags);
2434 }
2435 
musb_h_get_frame_number(struct usb_hcd * hcd)2436 static int musb_h_get_frame_number(struct usb_hcd *hcd)
2437 {
2438 	struct musb	*musb = hcd_to_musb(hcd);
2439 
2440 	return musb_readw(musb->mregs, MUSB_FRAME);
2441 }
2442 
musb_h_start(struct usb_hcd * hcd)2443 static int musb_h_start(struct usb_hcd *hcd)
2444 {
2445 	struct musb	*musb = hcd_to_musb(hcd);
2446 
2447 	/* NOTE: musb_start() is called when the hub driver turns
2448 	 * on port power, or when (OTG) peripheral starts.
2449 	 */
2450 	hcd->state = HC_STATE_RUNNING;
2451 	musb->port1_status = 0;
2452 	return 0;
2453 }
2454 
musb_h_stop(struct usb_hcd * hcd)2455 static void musb_h_stop(struct usb_hcd *hcd)
2456 {
2457 	musb_stop(hcd_to_musb(hcd));
2458 	hcd->state = HC_STATE_HALT;
2459 }
2460 
musb_bus_suspend(struct usb_hcd * hcd)2461 static int musb_bus_suspend(struct usb_hcd *hcd)
2462 {
2463 	struct musb	*musb = hcd_to_musb(hcd);
2464 	u8		devctl;
2465 
2466 	musb_port_suspend(musb, true);
2467 
2468 	if (!is_host_active(musb))
2469 		return 0;
2470 
2471 	switch (musb->xceiv->state) {
2472 	case OTG_STATE_A_SUSPEND:
2473 		return 0;
2474 	case OTG_STATE_A_WAIT_VRISE:
2475 		/* ID could be grounded even if there's no device
2476 		 * on the other end of the cable.  NOTE that the
2477 		 * A_WAIT_VRISE timers are messy with MUSB...
2478 		 */
2479 		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2480 		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2481 			musb->xceiv->state = OTG_STATE_A_WAIT_BCON;
2482 		break;
2483 	default:
2484 		break;
2485 	}
2486 
2487 	if (musb->is_active) {
2488 		WARNING("trying to suspend as %s while active\n",
2489 				usb_otg_state_string(musb->xceiv->state));
2490 		return -EBUSY;
2491 	} else
2492 		return 0;
2493 }
2494 
musb_bus_resume(struct usb_hcd * hcd)2495 static int musb_bus_resume(struct usb_hcd *hcd)
2496 {
2497 	struct musb *musb = hcd_to_musb(hcd);
2498 
2499 	if (musb->config &&
2500 	    musb->config->host_port_deassert_reset_at_resume)
2501 		musb_port_reset(musb, false);
2502 
2503 	return 0;
2504 }
2505 
2506 #ifndef CONFIG_MUSB_PIO_ONLY
2507 
2508 #define MUSB_USB_DMA_ALIGN 4
2509 
2510 struct musb_temp_buffer {
2511 	void *kmalloc_ptr;
2512 	void *old_xfer_buffer;
2513 	u8 data[0];
2514 };
2515 
musb_free_temp_buffer(struct urb * urb)2516 static void musb_free_temp_buffer(struct urb *urb)
2517 {
2518 	enum dma_data_direction dir;
2519 	struct musb_temp_buffer *temp;
2520 
2521 	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
2522 		return;
2523 
2524 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2525 
2526 	temp = container_of(urb->transfer_buffer, struct musb_temp_buffer,
2527 			    data);
2528 
2529 	if (dir == DMA_FROM_DEVICE) {
2530 		memcpy(temp->old_xfer_buffer, temp->data,
2531 		       urb->transfer_buffer_length);
2532 	}
2533 	urb->transfer_buffer = temp->old_xfer_buffer;
2534 	kfree(temp->kmalloc_ptr);
2535 
2536 	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
2537 }
2538 
musb_alloc_temp_buffer(struct urb * urb,gfp_t mem_flags)2539 static int musb_alloc_temp_buffer(struct urb *urb, gfp_t mem_flags)
2540 {
2541 	enum dma_data_direction dir;
2542 	struct musb_temp_buffer *temp;
2543 	void *kmalloc_ptr;
2544 	size_t kmalloc_size;
2545 
2546 	if (urb->num_sgs || urb->sg ||
2547 	    urb->transfer_buffer_length == 0 ||
2548 	    !((uintptr_t)urb->transfer_buffer & (MUSB_USB_DMA_ALIGN - 1)))
2549 		return 0;
2550 
2551 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2552 
2553 	/* Allocate a buffer with enough padding for alignment */
2554 	kmalloc_size = urb->transfer_buffer_length +
2555 		sizeof(struct musb_temp_buffer) + MUSB_USB_DMA_ALIGN - 1;
2556 
2557 	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
2558 	if (!kmalloc_ptr)
2559 		return -ENOMEM;
2560 
2561 	/* Position our struct temp_buffer such that data is aligned */
2562 	temp = PTR_ALIGN(kmalloc_ptr, MUSB_USB_DMA_ALIGN);
2563 
2564 
2565 	temp->kmalloc_ptr = kmalloc_ptr;
2566 	temp->old_xfer_buffer = urb->transfer_buffer;
2567 	if (dir == DMA_TO_DEVICE)
2568 		memcpy(temp->data, urb->transfer_buffer,
2569 		       urb->transfer_buffer_length);
2570 	urb->transfer_buffer = temp->data;
2571 
2572 	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
2573 
2574 	return 0;
2575 }
2576 
musb_map_urb_for_dma(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)2577 static int musb_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
2578 				      gfp_t mem_flags)
2579 {
2580 	struct musb	*musb = hcd_to_musb(hcd);
2581 	int ret;
2582 
2583 	/*
2584 	 * The DMA engine in RTL1.8 and above cannot handle
2585 	 * DMA addresses that are not aligned to a 4 byte boundary.
2586 	 * For such engine implemented (un)map_urb_for_dma hooks.
2587 	 * Do not use these hooks for RTL<1.8
2588 	 */
2589 	if (musb->hwvers < MUSB_HWVERS_1800)
2590 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2591 
2592 	ret = musb_alloc_temp_buffer(urb, mem_flags);
2593 	if (ret)
2594 		return ret;
2595 
2596 	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2597 	if (ret)
2598 		musb_free_temp_buffer(urb);
2599 
2600 	return ret;
2601 }
2602 
musb_unmap_urb_for_dma(struct usb_hcd * hcd,struct urb * urb)2603 static void musb_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
2604 {
2605 	struct musb	*musb = hcd_to_musb(hcd);
2606 
2607 	usb_hcd_unmap_urb_for_dma(hcd, urb);
2608 
2609 	/* Do not use this hook for RTL<1.8 (see description above) */
2610 	if (musb->hwvers < MUSB_HWVERS_1800)
2611 		return;
2612 
2613 	musb_free_temp_buffer(urb);
2614 }
2615 #endif /* !CONFIG_MUSB_PIO_ONLY */
2616 
2617 static const struct hc_driver musb_hc_driver = {
2618 	.description		= "musb-hcd",
2619 	.product_desc		= "MUSB HDRC host driver",
2620 	.hcd_priv_size		= sizeof(struct musb *),
2621 	.flags			= HCD_USB2 | HCD_MEMORY,
2622 
2623 	/* not using irq handler or reset hooks from usbcore, since
2624 	 * those must be shared with peripheral code for OTG configs
2625 	 */
2626 
2627 	.start			= musb_h_start,
2628 	.stop			= musb_h_stop,
2629 
2630 	.get_frame_number	= musb_h_get_frame_number,
2631 
2632 	.urb_enqueue		= musb_urb_enqueue,
2633 	.urb_dequeue		= musb_urb_dequeue,
2634 	.endpoint_disable	= musb_h_disable,
2635 
2636 #ifndef CONFIG_MUSB_PIO_ONLY
2637 	.map_urb_for_dma	= musb_map_urb_for_dma,
2638 	.unmap_urb_for_dma	= musb_unmap_urb_for_dma,
2639 #endif
2640 
2641 	.hub_status_data	= musb_hub_status_data,
2642 	.hub_control		= musb_hub_control,
2643 	.bus_suspend		= musb_bus_suspend,
2644 	.bus_resume		= musb_bus_resume,
2645 	/* .start_port_reset	= NULL, */
2646 	/* .hub_irq_enable	= NULL, */
2647 };
2648 
musb_host_alloc(struct musb * musb)2649 int musb_host_alloc(struct musb *musb)
2650 {
2651 	struct device	*dev = musb->controller;
2652 
2653 	/* usbcore sets dev->driver_data to hcd, and sometimes uses that... */
2654 	musb->hcd = usb_create_hcd(&musb_hc_driver, dev, dev_name(dev));
2655 	if (!musb->hcd)
2656 		return -EINVAL;
2657 
2658 	*musb->hcd->hcd_priv = (unsigned long) musb;
2659 	musb->hcd->self.uses_pio_for_control = 1;
2660 	musb->hcd->uses_new_polling = 1;
2661 	musb->hcd->has_tt = 1;
2662 
2663 	return 0;
2664 }
2665 
musb_host_cleanup(struct musb * musb)2666 void musb_host_cleanup(struct musb *musb)
2667 {
2668 	if (musb->port_mode == MUSB_PORT_MODE_GADGET)
2669 		return;
2670 	usb_remove_hcd(musb->hcd);
2671 }
2672 
musb_host_free(struct musb * musb)2673 void musb_host_free(struct musb *musb)
2674 {
2675 	usb_put_hcd(musb->hcd);
2676 }
2677 
musb_host_setup(struct musb * musb,int power_budget)2678 int musb_host_setup(struct musb *musb, int power_budget)
2679 {
2680 	int ret;
2681 	struct usb_hcd *hcd = musb->hcd;
2682 
2683 	MUSB_HST_MODE(musb);
2684 	musb->xceiv->otg->default_a = 1;
2685 	musb->xceiv->state = OTG_STATE_A_IDLE;
2686 
2687 	otg_set_host(musb->xceiv->otg, &hcd->self);
2688 	hcd->self.otg_port = 1;
2689 	musb->xceiv->otg->host = &hcd->self;
2690 	hcd->power_budget = 2 * (power_budget ? : 250);
2691 
2692 	ret = usb_add_hcd(hcd, 0, 0);
2693 	if (ret < 0)
2694 		return ret;
2695 
2696 	device_wakeup_enable(hcd->self.controller);
2697 	return 0;
2698 }
2699 
musb_host_resume_root_hub(struct musb * musb)2700 void musb_host_resume_root_hub(struct musb *musb)
2701 {
2702 	usb_hcd_resume_root_hub(musb->hcd);
2703 }
2704 
musb_host_poke_root_hub(struct musb * musb)2705 void musb_host_poke_root_hub(struct musb *musb)
2706 {
2707 	MUSB_HST_MODE(musb);
2708 	if (musb->hcd->status_urb)
2709 		usb_hcd_poll_rh_status(musb->hcd);
2710 	else
2711 		usb_hcd_resume_root_hub(musb->hcd);
2712 }
2713