xref: /openbmc/u-boot/drivers/usb/gadget/at91_udc.c (revision dbb0696b)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * from linux:
4  * c94e289f195e: usb: gadget: remove incorrect __init/__exit annotations
5  *
6  * at91_udc -- driver for at91-series USB peripheral controller
7  *
8  * Copyright (C) 2004 by Thomas Rathbone
9  * Copyright (C) 2005 by HP Labs
10  * Copyright (C) 2005 by David Brownell
11  */
12 
13 #undef	VERBOSE_DEBUG
14 #undef	PACKET_TRACE
15 
16 #include <common.h>
17 #include <linux/errno.h>
18 #include <asm/io.h>
19 #include <asm/gpio.h>
20 #include <asm/hardware.h>
21 #include <mach/at91_matrix.h>
22 #include <linux/list.h>
23 #include <linux/usb/ch9.h>
24 #include <linux/usb/gadget.h>
25 #include <linux/usb/at91_udc.h>
26 #include <malloc.h>
27 
28 #include "at91_udc.h"
29 
30 /*
31  * This controller is simple and PIO-only.  It's used in many AT91-series
32  * full speed USB controllers, including the at91rm9200 (arm920T, with MMU),
33  * at91sam926x (arm926ejs, with MMU), and several no-mmu versions.
34  *
35  * This driver expects the board has been wired with two GPIOs supporting
36  * a VBUS sensing IRQ, and a D+ pullup.  (They may be omitted, but the
37  * testing hasn't covered such cases.)
38  *
39  * The pullup is most important (so it's integrated on sam926x parts).  It
40  * provides software control over whether the host enumerates the device.
41  *
42  * The VBUS sensing helps during enumeration, and allows both USB clocks
43  * (and the transceiver) to stay gated off until they're necessary, saving
44  * power.  During USB suspend, the 48 MHz clock is gated off in hardware;
45  * it may also be gated off by software during some Linux sleep states.
46  */
47 
48 #define	DRIVER_VERSION	"3 May 2006"
49 
50 static const char driver_name [] = "at91_udc";
51 static const char * const ep_names[] = {
52 	"ep0",
53 	"ep1",
54 	"ep2",
55 	"ep3-int",
56 	"ep4",
57 	"ep5",
58 };
59 #define ep0name		ep_names[0]
60 
61 #define at91_udp_read(udc, reg) \
62 	__raw_readl((udc)->udp_baseaddr + (reg))
63 #define at91_udp_write(udc, reg, val) \
64 	__raw_writel((val), (udc)->udp_baseaddr + (reg))
65 
66 static struct at91_udc *controller;
67 
68 /*-------------------------------------------------------------------------*/
69 
70 static void done(struct at91_ep *ep, struct at91_request *req, int status)
71 {
72 	unsigned	stopped = ep->stopped;
73 	struct at91_udc	*udc = ep->udc;
74 
75 	list_del_init(&req->queue);
76 	if (req->req.status == -EINPROGRESS)
77 		req->req.status = status;
78 	else
79 		status = req->req.status;
80 	if (status && status != -ESHUTDOWN)
81 		VDBG("%s done %p, status %d\n", ep->ep.name, req, status);
82 
83 	ep->stopped = 1;
84 	spin_unlock(&udc->lock);
85 	req->req.complete(&ep->ep, &req->req);
86 	spin_lock(&udc->lock);
87 	ep->stopped = stopped;
88 
89 	/* ep0 is always ready; other endpoints need a non-empty queue */
90 	if (list_empty(&ep->queue) && ep->int_mask != (1 << 0))
91 		at91_udp_write(udc, AT91_UDP_IDR, ep->int_mask);
92 }
93 
94 /*-------------------------------------------------------------------------*/
95 
96 /* bits indicating OUT fifo has data ready */
97 #define	RX_DATA_READY	(AT91_UDP_RX_DATA_BK0 | AT91_UDP_RX_DATA_BK1)
98 
99 /*
100  * Endpoint FIFO CSR bits have a mix of bits, making it unsafe to just write
101  * back most of the value you just read (because of side effects, including
102  * bits that may change after reading and before writing).
103  *
104  * Except when changing a specific bit, always write values which:
105  *  - clear SET_FX bits (setting them could change something)
106  *  - set CLR_FX bits (clearing them could change something)
107  *
108  * There are also state bits like FORCESTALL, EPEDS, DIR, and EPTYPE
109  * that shouldn't normally be changed.
110  *
111  * NOTE at91sam9260 docs mention synch between UDPCK and MCK clock domains,
112  * implying a need to wait for one write to complete (test relevant bits)
113  * before starting the next write.  This shouldn't be an issue given how
114  * infrequently we write, except maybe for write-then-read idioms.
115  */
116 #define	SET_FX	(AT91_UDP_TXPKTRDY)
117 #define	CLR_FX	(RX_DATA_READY | AT91_UDP_RXSETUP \
118 		| AT91_UDP_STALLSENT | AT91_UDP_TXCOMP)
119 
120 /* pull OUT packet data from the endpoint's fifo */
121 static int read_fifo (struct at91_ep *ep, struct at91_request *req)
122 {
123 	u32 __iomem	*creg = ep->creg;
124 	u8 __iomem	*dreg = ep->creg + (AT91_UDP_FDR(0) - AT91_UDP_CSR(0));
125 	u32		csr;
126 	u8		*buf;
127 	unsigned int	count, bufferspace, is_done;
128 
129 	buf = req->req.buf + req->req.actual;
130 	bufferspace = req->req.length - req->req.actual;
131 
132 	/*
133 	 * there might be nothing to read if ep_queue() calls us,
134 	 * or if we already emptied both pingpong buffers
135 	 */
136 rescan:
137 	csr = __raw_readl(creg);
138 	if ((csr & RX_DATA_READY) == 0)
139 		return 0;
140 
141 	count = (csr & AT91_UDP_RXBYTECNT) >> 16;
142 	if (count > ep->ep.maxpacket)
143 		count = ep->ep.maxpacket;
144 	if (count > bufferspace) {
145 		DBG("%s buffer overflow\n", ep->ep.name);
146 		req->req.status = -EOVERFLOW;
147 		count = bufferspace;
148 	}
149 	__raw_readsb((unsigned long)dreg, buf, count);
150 
151 	/* release and swap pingpong mem bank */
152 	csr |= CLR_FX;
153 	if (ep->is_pingpong) {
154 		if (ep->fifo_bank == 0) {
155 			csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK0);
156 			ep->fifo_bank = 1;
157 		} else {
158 			csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK1);
159 			ep->fifo_bank = 0;
160 		}
161 	} else
162 		csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK0);
163 	__raw_writel(csr, creg);
164 
165 	req->req.actual += count;
166 	is_done = (count < ep->ep.maxpacket);
167 	if (count == bufferspace)
168 		is_done = 1;
169 
170 	PACKET("%s %p out/%d%s\n", ep->ep.name, &req->req, count,
171 			is_done ? " (done)" : "");
172 
173 	/*
174 	 * avoid extra trips through IRQ logic for packets already in
175 	 * the fifo ... maybe preventing an extra (expensive) OUT-NAK
176 	 */
177 	if (is_done)
178 		done(ep, req, 0);
179 	else if (ep->is_pingpong) {
180 		/*
181 		 * One dummy read to delay the code because of a HW glitch:
182 		 * CSR returns bad RXCOUNT when read too soon after updating
183 		 * RX_DATA_BK flags.
184 		 */
185 		csr = __raw_readl(creg);
186 
187 		bufferspace -= count;
188 		buf += count;
189 		goto rescan;
190 	}
191 
192 	return is_done;
193 }
194 
195 /* load fifo for an IN packet */
196 static int write_fifo(struct at91_ep *ep, struct at91_request *req)
197 {
198 	u32 __iomem	*creg = ep->creg;
199 	u32		csr = __raw_readl(creg);
200 	u8 __iomem	*dreg = ep->creg + (AT91_UDP_FDR(0) - AT91_UDP_CSR(0));
201 	unsigned	total, count, is_last;
202 	u8		*buf;
203 
204 	/*
205 	 * TODO: allow for writing two packets to the fifo ... that'll
206 	 * reduce the amount of IN-NAKing, but probably won't affect
207 	 * throughput much.  (Unlike preventing OUT-NAKing!)
208 	 */
209 
210 	/*
211 	 * If ep_queue() calls us, the queue is empty and possibly in
212 	 * odd states like TXCOMP not yet cleared (we do it, saving at
213 	 * least one IRQ) or the fifo not yet being free.  Those aren't
214 	 * issues normally (IRQ handler fast path).
215 	 */
216 	if (unlikely(csr & (AT91_UDP_TXCOMP | AT91_UDP_TXPKTRDY))) {
217 		if (csr & AT91_UDP_TXCOMP) {
218 			csr |= CLR_FX;
219 			csr &= ~(SET_FX | AT91_UDP_TXCOMP);
220 			__raw_writel(csr, creg);
221 			csr = __raw_readl(creg);
222 		}
223 		if (csr & AT91_UDP_TXPKTRDY)
224 			return 0;
225 	}
226 
227 	buf = req->req.buf + req->req.actual;
228 	prefetch(buf);
229 	total = req->req.length - req->req.actual;
230 	if (ep->ep.maxpacket < total) {
231 		count = ep->ep.maxpacket;
232 		is_last = 0;
233 	} else {
234 		count = total;
235 		is_last = (count < ep->ep.maxpacket) || !req->req.zero;
236 	}
237 
238 	/*
239 	 * Write the packet, maybe it's a ZLP.
240 	 *
241 	 * NOTE:  incrementing req->actual before we receive the ACK means
242 	 * gadget driver IN bytecounts can be wrong in fault cases.  That's
243 	 * fixable with PIO drivers like this one (save "count" here, and
244 	 * do the increment later on TX irq), but not for most DMA hardware.
245 	 *
246 	 * So all gadget drivers must accept that potential error.  Some
247 	 * hardware supports precise fifo status reporting, letting them
248 	 * recover when the actual bytecount matters (e.g. for USB Test
249 	 * and Measurement Class devices).
250 	 */
251 	__raw_writesb((unsigned long)dreg, buf, count);
252 	csr &= ~SET_FX;
253 	csr |= CLR_FX | AT91_UDP_TXPKTRDY;
254 	__raw_writel(csr, creg);
255 	req->req.actual += count;
256 
257 	PACKET("%s %p in/%d%s\n", ep->ep.name, &req->req, count,
258 			is_last ? " (done)" : "");
259 	if (is_last)
260 		done(ep, req, 0);
261 	return is_last;
262 }
263 
264 static void nuke(struct at91_ep *ep, int status)
265 {
266 	struct at91_request *req;
267 
268 	/* terminate any request in the queue */
269 	ep->stopped = 1;
270 	if (list_empty(&ep->queue))
271 		return;
272 
273 	VDBG("%s %s\n", __func__, ep->ep.name);
274 	while (!list_empty(&ep->queue)) {
275 		req = list_entry(ep->queue.next, struct at91_request, queue);
276 		done(ep, req, status);
277 	}
278 }
279 
280 /*-------------------------------------------------------------------------*/
281 
282 static int at91_ep_enable(struct usb_ep *_ep,
283 				const struct usb_endpoint_descriptor *desc)
284 {
285 	struct at91_ep	*ep = container_of(_ep, struct at91_ep, ep);
286 	struct at91_udc *udc;
287 	u16		maxpacket;
288 	u32		tmp;
289 	unsigned long	flags;
290 
291 	if (!_ep || !ep
292 			|| !desc || _ep->name == ep0name
293 			|| desc->bDescriptorType != USB_DT_ENDPOINT
294 			|| (maxpacket = usb_endpoint_maxp(desc)) == 0
295 			|| maxpacket > ep->maxpacket) {
296 		DBG("bad ep or descriptor\n");
297 		return -EINVAL;
298 	}
299 
300 	udc = ep->udc;
301 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
302 		DBG("bogus device state\n");
303 		return -ESHUTDOWN;
304 	}
305 
306 	tmp = usb_endpoint_type(desc);
307 	switch (tmp) {
308 	case USB_ENDPOINT_XFER_CONTROL:
309 		DBG("only one control endpoint\n");
310 		return -EINVAL;
311 	case USB_ENDPOINT_XFER_INT:
312 		if (maxpacket > 64)
313 			goto bogus_max;
314 		break;
315 	case USB_ENDPOINT_XFER_BULK:
316 		switch (maxpacket) {
317 		case 8:
318 		case 16:
319 		case 32:
320 		case 64:
321 			goto ok;
322 		}
323 bogus_max:
324 		DBG("bogus maxpacket %d\n", maxpacket);
325 		return -EINVAL;
326 	case USB_ENDPOINT_XFER_ISOC:
327 		if (!ep->is_pingpong) {
328 			DBG("iso requires double buffering\n");
329 			return -EINVAL;
330 		}
331 		break;
332 	}
333 
334 ok:
335 	spin_lock_irqsave(&udc->lock, flags);
336 
337 	/* initialize endpoint to match this descriptor */
338 	ep->is_in = usb_endpoint_dir_in(desc);
339 	ep->is_iso = (tmp == USB_ENDPOINT_XFER_ISOC);
340 	ep->stopped = 0;
341 	if (ep->is_in)
342 		tmp |= 0x04;
343 	tmp <<= 8;
344 	tmp |= AT91_UDP_EPEDS;
345 	__raw_writel(tmp, ep->creg);
346 
347 	ep->ep.maxpacket = maxpacket;
348 
349 	/*
350 	 * reset/init endpoint fifo.  NOTE:  leaves fifo_bank alone,
351 	 * since endpoint resets don't reset hw pingpong state.
352 	 */
353 	at91_udp_write(udc, AT91_UDP_RST_EP, ep->int_mask);
354 	at91_udp_write(udc, AT91_UDP_RST_EP, 0);
355 
356 	spin_unlock_irqrestore(&udc->lock, flags);
357 	return 0;
358 }
359 
360 static int at91_ep_disable (struct usb_ep * _ep)
361 {
362 	struct at91_ep	*ep = container_of(_ep, struct at91_ep, ep);
363 	struct at91_udc	*udc = ep->udc;
364 	unsigned long	flags;
365 
366 	if (ep == &ep->udc->ep[0])
367 		return -EINVAL;
368 
369 	spin_lock_irqsave(&udc->lock, flags);
370 
371 	nuke(ep, -ESHUTDOWN);
372 
373 	/* restore the endpoint's pristine config */
374 	ep->ep.desc = NULL;
375 	ep->ep.maxpacket = ep->maxpacket;
376 
377 	/* reset fifos and endpoint */
378 	if (ep->udc->clocked) {
379 		at91_udp_write(udc, AT91_UDP_RST_EP, ep->int_mask);
380 		at91_udp_write(udc, AT91_UDP_RST_EP, 0);
381 		__raw_writel(0, ep->creg);
382 	}
383 
384 	spin_unlock_irqrestore(&udc->lock, flags);
385 	return 0;
386 }
387 
388 /*
389  * this is a PIO-only driver, so there's nothing
390  * interesting for request or buffer allocation.
391  */
392 
393 static struct usb_request *
394 at91_ep_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
395 {
396 	struct at91_request *req;
397 
398 	req = kzalloc(sizeof (struct at91_request), gfp_flags);
399 	if (!req)
400 		return NULL;
401 
402 	INIT_LIST_HEAD(&req->queue);
403 	return &req->req;
404 }
405 
406 static void at91_ep_free_request(struct usb_ep *_ep, struct usb_request *_req)
407 {
408 	struct at91_request *req;
409 
410 	req = container_of(_req, struct at91_request, req);
411 	BUG_ON(!list_empty(&req->queue));
412 	kfree(req);
413 }
414 
415 static int at91_ep_queue(struct usb_ep *_ep,
416 			struct usb_request *_req, gfp_t gfp_flags)
417 {
418 	struct at91_request	*req;
419 	struct at91_ep		*ep;
420 	struct at91_udc		*udc;
421 	int			status;
422 	unsigned long		flags;
423 
424 	req = container_of(_req, struct at91_request, req);
425 	ep = container_of(_ep, struct at91_ep, ep);
426 
427 	if (!_req || !_req->complete
428 			|| !_req->buf || !list_empty(&req->queue)) {
429 		DBG("invalid request\n");
430 		return -EINVAL;
431 	}
432 
433 	if (!_ep || (!ep->ep.desc && ep->ep.name != ep0name)) {
434 		DBG("invalid ep\n");
435 		return -EINVAL;
436 	}
437 
438 	udc = ep->udc;
439 
440 	if (!udc || !udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
441 		DBG("invalid device\n");
442 		return -EINVAL;
443 	}
444 
445 	_req->status = -EINPROGRESS;
446 	_req->actual = 0;
447 
448 	spin_lock_irqsave(&udc->lock, flags);
449 
450 	/* try to kickstart any empty and idle queue */
451 	if (list_empty(&ep->queue) && !ep->stopped) {
452 		int	is_ep0;
453 
454 		/*
455 		 * If this control request has a non-empty DATA stage, this
456 		 * will start that stage.  It works just like a non-control
457 		 * request (until the status stage starts, maybe early).
458 		 *
459 		 * If the data stage is empty, then this starts a successful
460 		 * IN/STATUS stage.  (Unsuccessful ones use set_halt.)
461 		 */
462 		is_ep0 = (ep->ep.name == ep0name);
463 		if (is_ep0) {
464 			u32	tmp;
465 
466 			if (!udc->req_pending) {
467 				status = -EINVAL;
468 				goto done;
469 			}
470 
471 			/*
472 			 * defer changing CONFG until after the gadget driver
473 			 * reconfigures the endpoints.
474 			 */
475 			if (udc->wait_for_config_ack) {
476 				tmp = at91_udp_read(udc, AT91_UDP_GLB_STAT);
477 				tmp ^= AT91_UDP_CONFG;
478 				VDBG("toggle config\n");
479 				at91_udp_write(udc, AT91_UDP_GLB_STAT, tmp);
480 			}
481 			if (req->req.length == 0) {
482 ep0_in_status:
483 				PACKET("ep0 in/status\n");
484 				status = 0;
485 				tmp = __raw_readl(ep->creg);
486 				tmp &= ~SET_FX;
487 				tmp |= CLR_FX | AT91_UDP_TXPKTRDY;
488 				__raw_writel(tmp, ep->creg);
489 				udc->req_pending = 0;
490 				goto done;
491 			}
492 		}
493 
494 		if (ep->is_in)
495 			status = write_fifo(ep, req);
496 		else {
497 			status = read_fifo(ep, req);
498 
499 			/* IN/STATUS stage is otherwise triggered by irq */
500 			if (status && is_ep0)
501 				goto ep0_in_status;
502 		}
503 	} else
504 		status = 0;
505 
506 	if (req && !status) {
507 		list_add_tail (&req->queue, &ep->queue);
508 		at91_udp_write(udc, AT91_UDP_IER, ep->int_mask);
509 	}
510 done:
511 	spin_unlock_irqrestore(&udc->lock, flags);
512 	return (status < 0) ? status : 0;
513 }
514 
515 static int at91_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
516 {
517 	struct at91_ep		*ep;
518 	struct at91_request	*req;
519 	unsigned long		flags;
520 
521 	ep = container_of(_ep, struct at91_ep, ep);
522 	if (!_ep || ep->ep.name == ep0name)
523 		return -EINVAL;
524 
525 	spin_lock_irqsave(&udc->lock, flags);
526 
527 	/* make sure it's actually queued on this endpoint */
528 	list_for_each_entry (req, &ep->queue, queue) {
529 		if (&req->req == _req)
530 			break;
531 	}
532 	if (&req->req != _req) {
533 		spin_unlock_irqrestore(&udc->lock, flags);
534 		return -EINVAL;
535 	}
536 
537 	done(ep, req, -ECONNRESET);
538 	spin_unlock_irqrestore(&udc->lock, flags);
539 	return 0;
540 }
541 
542 static int at91_ep_set_halt(struct usb_ep *_ep, int value)
543 {
544 	struct at91_ep	*ep = container_of(_ep, struct at91_ep, ep);
545 	struct at91_udc	*udc = ep->udc;
546 	u32 __iomem	*creg;
547 	u32		csr;
548 	unsigned long	flags;
549 	int		status = 0;
550 
551 	if (!_ep || ep->is_iso || !ep->udc->clocked)
552 		return -EINVAL;
553 
554 	creg = ep->creg;
555 	spin_lock_irqsave(&udc->lock, flags);
556 
557 	csr = __raw_readl(creg);
558 
559 	/*
560 	 * fail with still-busy IN endpoints, ensuring correct sequencing
561 	 * of data tx then stall.  note that the fifo rx bytecount isn't
562 	 * completely accurate as a tx bytecount.
563 	 */
564 	if (ep->is_in && (!list_empty(&ep->queue) || (csr >> 16) != 0))
565 		status = -EAGAIN;
566 	else {
567 		csr |= CLR_FX;
568 		csr &= ~SET_FX;
569 		if (value) {
570 			csr |= AT91_UDP_FORCESTALL;
571 			VDBG("halt %s\n", ep->ep.name);
572 		} else {
573 			at91_udp_write(udc, AT91_UDP_RST_EP, ep->int_mask);
574 			at91_udp_write(udc, AT91_UDP_RST_EP, 0);
575 			csr &= ~AT91_UDP_FORCESTALL;
576 		}
577 		__raw_writel(csr, creg);
578 	}
579 
580 	spin_unlock_irqrestore(&udc->lock, flags);
581 	return status;
582 }
583 
584 static const struct usb_ep_ops at91_ep_ops = {
585 	.enable		= at91_ep_enable,
586 	.disable	= at91_ep_disable,
587 	.alloc_request	= at91_ep_alloc_request,
588 	.free_request	= at91_ep_free_request,
589 	.queue		= at91_ep_queue,
590 	.dequeue	= at91_ep_dequeue,
591 	.set_halt	= at91_ep_set_halt,
592 	/* there's only imprecise fifo status reporting */
593 };
594 
595 /*-------------------------------------------------------------------------*/
596 
597 static int at91_get_frame(struct usb_gadget *gadget)
598 {
599 	struct at91_udc *udc = to_udc(gadget);
600 
601 	if (!to_udc(gadget)->clocked)
602 		return -EINVAL;
603 	return at91_udp_read(udc, AT91_UDP_FRM_NUM) & AT91_UDP_NUM;
604 }
605 
606 static int at91_wakeup(struct usb_gadget *gadget)
607 {
608 	struct at91_udc	*udc = to_udc(gadget);
609 	u32		glbstate;
610 	int		status = -EINVAL;
611 	unsigned long	flags;
612 
613 	DBG("%s\n", __func__ );
614 	spin_lock_irqsave(&udc->lock, flags);
615 
616 	if (!udc->clocked || !udc->suspended)
617 		goto done;
618 
619 	/* NOTE:  some "early versions" handle ESR differently ... */
620 
621 	glbstate = at91_udp_read(udc, AT91_UDP_GLB_STAT);
622 	if (!(glbstate & AT91_UDP_ESR))
623 		goto done;
624 	glbstate |= AT91_UDP_ESR;
625 	at91_udp_write(udc, AT91_UDP_GLB_STAT, glbstate);
626 
627 done:
628 	spin_unlock_irqrestore(&udc->lock, flags);
629 	return status;
630 }
631 
632 /* reinit == restore initial software state */
633 static void udc_reinit(struct at91_udc *udc)
634 {
635 	u32 i;
636 
637 	INIT_LIST_HEAD(&udc->gadget.ep_list);
638 	INIT_LIST_HEAD(&udc->gadget.ep0->ep_list);
639 
640 	for (i = 0; i < NUM_ENDPOINTS; i++) {
641 		struct at91_ep *ep = &udc->ep[i];
642 
643 		if (i != 0)
644 			list_add_tail(&ep->ep.ep_list, &udc->gadget.ep_list);
645 		ep->ep.desc = NULL;
646 		ep->stopped = 0;
647 		ep->fifo_bank = 0;
648 		usb_ep_set_maxpacket_limit(&ep->ep, ep->maxpacket);
649 		ep->creg = (void __iomem *) udc->udp_baseaddr + AT91_UDP_CSR(i);
650 		/* initialize one queue per endpoint */
651 		INIT_LIST_HEAD(&ep->queue);
652 	}
653 }
654 
655 static void reset_gadget(struct at91_udc *udc)
656 {
657 	struct usb_gadget_driver *driver = udc->driver;
658 	int i;
659 
660 	if (udc->gadget.speed == USB_SPEED_UNKNOWN)
661 		driver = NULL;
662 	udc->gadget.speed = USB_SPEED_UNKNOWN;
663 	udc->suspended = 0;
664 
665 	for (i = 0; i < NUM_ENDPOINTS; i++) {
666 		struct at91_ep *ep = &udc->ep[i];
667 
668 		ep->stopped = 1;
669 		nuke(ep, -ESHUTDOWN);
670 	}
671 	if (driver) {
672 		spin_unlock(&udc->lock);
673 		udc->driver->disconnect(&udc->gadget);
674 		spin_lock(&udc->lock);
675 	}
676 
677 	udc_reinit(udc);
678 }
679 
680 static void stop_activity(struct at91_udc *udc)
681 {
682 	struct usb_gadget_driver *driver = udc->driver;
683 	int i;
684 
685 	if (udc->gadget.speed == USB_SPEED_UNKNOWN)
686 		driver = NULL;
687 	udc->gadget.speed = USB_SPEED_UNKNOWN;
688 	udc->suspended = 0;
689 
690 	for (i = 0; i < NUM_ENDPOINTS; i++) {
691 		struct at91_ep *ep = &udc->ep[i];
692 		ep->stopped = 1;
693 		nuke(ep, -ESHUTDOWN);
694 	}
695 	if (driver) {
696 		spin_unlock(&udc->lock);
697 		driver->disconnect(&udc->gadget);
698 		spin_lock(&udc->lock);
699 	}
700 
701 	udc_reinit(udc);
702 }
703 
704 static void clk_on(struct at91_udc *udc)
705 {
706 	if (udc->clocked)
707 		return;
708 	udc->clocked = 1;
709 }
710 
711 static void clk_off(struct at91_udc *udc)
712 {
713 	if (!udc->clocked)
714 		return;
715 	udc->clocked = 0;
716 	udc->gadget.speed = USB_SPEED_UNKNOWN;
717 }
718 
719 /*
720  * activate/deactivate link with host; minimize power usage for
721  * inactive links by cutting clocks and transceiver power.
722  */
723 static void pullup(struct at91_udc *udc, int is_on)
724 {
725 	if (!udc->enabled || !udc->vbus)
726 		is_on = 0;
727 	DBG("%sactive\n", is_on ? "" : "in");
728 
729 	if (is_on) {
730 		clk_on(udc);
731 		at91_udp_write(udc, AT91_UDP_ICR, AT91_UDP_RXRSM);
732 		at91_udp_write(udc, AT91_UDP_TXVC, 0);
733 	} else {
734 		stop_activity(udc);
735 		at91_udp_write(udc, AT91_UDP_IDR, AT91_UDP_RXRSM);
736 		at91_udp_write(udc, AT91_UDP_TXVC, AT91_UDP_TXVC_TXVDIS);
737 		clk_off(udc);
738 	}
739 
740 	if (udc->caps && udc->caps->pullup)
741 		udc->caps->pullup(udc, is_on);
742 }
743 
744 /* vbus is here!  turn everything on that's ready */
745 static int at91_vbus_session(struct usb_gadget *gadget, int is_active)
746 {
747 	struct at91_udc	*udc = to_udc(gadget);
748 	unsigned long	flags;
749 
750 	/* VDBG("vbus %s\n", is_active ? "on" : "off"); */
751 	spin_lock_irqsave(&udc->lock, flags);
752 	udc->vbus = (is_active != 0);
753 	if (udc->driver)
754 		pullup(udc, is_active);
755 	else
756 		pullup(udc, 0);
757 	spin_unlock_irqrestore(&udc->lock, flags);
758 	return 0;
759 }
760 
761 static int at91_pullup(struct usb_gadget *gadget, int is_on)
762 {
763 	struct at91_udc	*udc = to_udc(gadget);
764 	unsigned long	flags;
765 
766 	spin_lock_irqsave(&udc->lock, flags);
767 	udc->enabled = is_on = !!is_on;
768 	pullup(udc, is_on);
769 	spin_unlock_irqrestore(&udc->lock, flags);
770 	return 0;
771 }
772 
773 static int at91_set_selfpowered(struct usb_gadget *gadget, int is_on)
774 {
775 	struct at91_udc	*udc = to_udc(gadget);
776 	unsigned long	flags;
777 
778 	spin_lock_irqsave(&udc->lock, flags);
779 	udc->selfpowered = (is_on != 0);
780 	spin_unlock_irqrestore(&udc->lock, flags);
781 	return 0;
782 }
783 
784 static int at91_start(struct usb_gadget *gadget,
785 		struct usb_gadget_driver *driver);
786 static int at91_stop(struct usb_gadget *gadget);
787 
788 static const struct usb_gadget_ops at91_udc_ops = {
789 	.get_frame		= at91_get_frame,
790 	.wakeup			= at91_wakeup,
791 	.set_selfpowered	= at91_set_selfpowered,
792 	.vbus_session		= at91_vbus_session,
793 	.pullup			= at91_pullup,
794 	.udc_start		= at91_start,
795 	.udc_stop		= at91_stop,
796 
797 	/*
798 	 * VBUS-powered devices may also also want to support bigger
799 	 * power budgets after an appropriate SET_CONFIGURATION.
800 	 */
801 	/* .vbus_power		= at91_vbus_power, */
802 };
803 
804 /*-------------------------------------------------------------------------*/
805 
806 static int handle_ep(struct at91_ep *ep)
807 {
808 	struct at91_request	*req;
809 	u32 __iomem		*creg = ep->creg;
810 	u32			csr = __raw_readl(creg);
811 
812 	if (!list_empty(&ep->queue))
813 		req = list_entry(ep->queue.next,
814 			struct at91_request, queue);
815 	else
816 		req = NULL;
817 
818 	if (ep->is_in) {
819 		if (csr & (AT91_UDP_STALLSENT | AT91_UDP_TXCOMP)) {
820 			csr |= CLR_FX;
821 			csr &= ~(SET_FX | AT91_UDP_STALLSENT | AT91_UDP_TXCOMP);
822 			__raw_writel(csr, creg);
823 		}
824 		if (req)
825 			return write_fifo(ep, req);
826 
827 	} else {
828 		if (csr & AT91_UDP_STALLSENT) {
829 			/* STALLSENT bit == ISOERR */
830 			if (ep->is_iso && req)
831 				req->req.status = -EILSEQ;
832 			csr |= CLR_FX;
833 			csr &= ~(SET_FX | AT91_UDP_STALLSENT);
834 			__raw_writel(csr, creg);
835 			csr = __raw_readl(creg);
836 		}
837 		if (req && (csr & RX_DATA_READY))
838 			return read_fifo(ep, req);
839 	}
840 	return 0;
841 }
842 
843 union setup {
844 	u8			raw[8];
845 	struct usb_ctrlrequest	r;
846 };
847 
848 static void handle_setup(struct at91_udc *udc, struct at91_ep *ep, u32 csr)
849 {
850 	u32 __iomem	*creg = ep->creg;
851 	u8 __iomem	*dreg = ep->creg + (AT91_UDP_FDR(0) - AT91_UDP_CSR(0));
852 	unsigned	rxcount, i = 0;
853 	u32		tmp;
854 	union setup	pkt;
855 	int		status = 0;
856 
857 	/* read and ack SETUP; hard-fail for bogus packets */
858 	rxcount = (csr & AT91_UDP_RXBYTECNT) >> 16;
859 	if (likely(rxcount == 8)) {
860 		while (rxcount--)
861 			pkt.raw[i++] = __raw_readb(dreg);
862 		if (pkt.r.bRequestType & USB_DIR_IN) {
863 			csr |= AT91_UDP_DIR;
864 			ep->is_in = 1;
865 		} else {
866 			csr &= ~AT91_UDP_DIR;
867 			ep->is_in = 0;
868 		}
869 	} else {
870 		/* REVISIT this happens sometimes under load; why?? */
871 		ERR("SETUP len %d, csr %08x\n", rxcount, csr);
872 		status = -EINVAL;
873 	}
874 	csr |= CLR_FX;
875 	csr &= ~(SET_FX | AT91_UDP_RXSETUP);
876 	__raw_writel(csr, creg);
877 	udc->wait_for_addr_ack = 0;
878 	udc->wait_for_config_ack = 0;
879 	ep->stopped = 0;
880 	if (unlikely(status != 0))
881 		goto stall;
882 
883 #define w_index		le16_to_cpu(pkt.r.wIndex)
884 #define w_value		le16_to_cpu(pkt.r.wValue)
885 #define w_length	le16_to_cpu(pkt.r.wLength)
886 
887 	VDBG("SETUP %02x.%02x v%04x i%04x l%04x\n",
888 			pkt.r.bRequestType, pkt.r.bRequest,
889 			w_value, w_index, w_length);
890 
891 	/*
892 	 * A few standard requests get handled here, ones that touch
893 	 * hardware ... notably for device and endpoint features.
894 	 */
895 	udc->req_pending = 1;
896 	csr = __raw_readl(creg);
897 	csr |= CLR_FX;
898 	csr &= ~SET_FX;
899 	switch ((pkt.r.bRequestType << 8) | pkt.r.bRequest) {
900 
901 	case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8)
902 			| USB_REQ_SET_ADDRESS:
903 		__raw_writel(csr | AT91_UDP_TXPKTRDY, creg);
904 		udc->addr = w_value;
905 		udc->wait_for_addr_ack = 1;
906 		udc->req_pending = 0;
907 		/* FADDR is set later, when we ack host STATUS */
908 		return;
909 
910 	case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8)
911 			| USB_REQ_SET_CONFIGURATION:
912 		tmp = at91_udp_read(udc, AT91_UDP_GLB_STAT) & AT91_UDP_CONFG;
913 		if (pkt.r.wValue)
914 			udc->wait_for_config_ack = (tmp == 0);
915 		else
916 			udc->wait_for_config_ack = (tmp != 0);
917 		if (udc->wait_for_config_ack)
918 			VDBG("wait for config\n");
919 		/* CONFG is toggled later, if gadget driver succeeds */
920 		break;
921 
922 	/*
923 	 * Hosts may set or clear remote wakeup status, and
924 	 * devices may report they're VBUS powered.
925 	 */
926 	case ((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8)
927 			| USB_REQ_GET_STATUS:
928 		tmp = (udc->selfpowered << USB_DEVICE_SELF_POWERED);
929 		if (at91_udp_read(udc, AT91_UDP_GLB_STAT) & AT91_UDP_ESR)
930 			tmp |= (1 << USB_DEVICE_REMOTE_WAKEUP);
931 		PACKET("get device status\n");
932 		__raw_writeb(tmp, dreg);
933 		__raw_writeb(0, dreg);
934 		goto write_in;
935 		/* then STATUS starts later, automatically */
936 	case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8)
937 			| USB_REQ_SET_FEATURE:
938 		if (w_value != USB_DEVICE_REMOTE_WAKEUP)
939 			goto stall;
940 		tmp = at91_udp_read(udc, AT91_UDP_GLB_STAT);
941 		tmp |= AT91_UDP_ESR;
942 		at91_udp_write(udc, AT91_UDP_GLB_STAT, tmp);
943 		goto succeed;
944 	case ((USB_TYPE_STANDARD|USB_RECIP_DEVICE) << 8)
945 			| USB_REQ_CLEAR_FEATURE:
946 		if (w_value != USB_DEVICE_REMOTE_WAKEUP)
947 			goto stall;
948 		tmp = at91_udp_read(udc, AT91_UDP_GLB_STAT);
949 		tmp &= ~AT91_UDP_ESR;
950 		at91_udp_write(udc, AT91_UDP_GLB_STAT, tmp);
951 		goto succeed;
952 
953 	/*
954 	 * Interfaces have no feature settings; this is pretty useless.
955 	 * we won't even insist the interface exists...
956 	 */
957 	case ((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_INTERFACE) << 8)
958 			| USB_REQ_GET_STATUS:
959 		PACKET("get interface status\n");
960 		__raw_writeb(0, dreg);
961 		__raw_writeb(0, dreg);
962 		goto write_in;
963 		/* then STATUS starts later, automatically */
964 	case ((USB_TYPE_STANDARD|USB_RECIP_INTERFACE) << 8)
965 			| USB_REQ_SET_FEATURE:
966 	case ((USB_TYPE_STANDARD|USB_RECIP_INTERFACE) << 8)
967 			| USB_REQ_CLEAR_FEATURE:
968 		goto stall;
969 
970 	/*
971 	 * Hosts may clear bulk/intr endpoint halt after the gadget
972 	 * driver sets it (not widely used); or set it (for testing)
973 	 */
974 	case ((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_ENDPOINT) << 8)
975 			| USB_REQ_GET_STATUS:
976 		tmp = w_index & USB_ENDPOINT_NUMBER_MASK;
977 		ep = &udc->ep[tmp];
978 		if (tmp >= NUM_ENDPOINTS || (tmp && !ep->ep.desc))
979 			goto stall;
980 
981 		if (tmp) {
982 			if ((w_index & USB_DIR_IN)) {
983 				if (!ep->is_in)
984 					goto stall;
985 			} else if (ep->is_in)
986 				goto stall;
987 		}
988 		PACKET("get %s status\n", ep->ep.name);
989 		if (__raw_readl(ep->creg) & AT91_UDP_FORCESTALL)
990 			tmp = (1 << USB_ENDPOINT_HALT);
991 		else
992 			tmp = 0;
993 		__raw_writeb(tmp, dreg);
994 		__raw_writeb(0, dreg);
995 		goto write_in;
996 		/* then STATUS starts later, automatically */
997 	case ((USB_TYPE_STANDARD|USB_RECIP_ENDPOINT) << 8)
998 			| USB_REQ_SET_FEATURE:
999 		tmp = w_index & USB_ENDPOINT_NUMBER_MASK;
1000 		ep = &udc->ep[tmp];
1001 		if (w_value != USB_ENDPOINT_HALT || tmp >= NUM_ENDPOINTS)
1002 			goto stall;
1003 		if (!ep->ep.desc || ep->is_iso)
1004 			goto stall;
1005 		if ((w_index & USB_DIR_IN)) {
1006 			if (!ep->is_in)
1007 				goto stall;
1008 		} else if (ep->is_in)
1009 			goto stall;
1010 
1011 		tmp = __raw_readl(ep->creg);
1012 		tmp &= ~SET_FX;
1013 		tmp |= CLR_FX | AT91_UDP_FORCESTALL;
1014 		__raw_writel(tmp, ep->creg);
1015 		goto succeed;
1016 	case ((USB_TYPE_STANDARD|USB_RECIP_ENDPOINT) << 8)
1017 			| USB_REQ_CLEAR_FEATURE:
1018 		tmp = w_index & USB_ENDPOINT_NUMBER_MASK;
1019 		ep = &udc->ep[tmp];
1020 		if (w_value != USB_ENDPOINT_HALT || tmp >= NUM_ENDPOINTS)
1021 			goto stall;
1022 		if (tmp == 0)
1023 			goto succeed;
1024 		if (!ep->ep.desc || ep->is_iso)
1025 			goto stall;
1026 		if ((w_index & USB_DIR_IN)) {
1027 			if (!ep->is_in)
1028 				goto stall;
1029 		} else if (ep->is_in)
1030 			goto stall;
1031 
1032 		at91_udp_write(udc, AT91_UDP_RST_EP, ep->int_mask);
1033 		at91_udp_write(udc, AT91_UDP_RST_EP, 0);
1034 		tmp = __raw_readl(ep->creg);
1035 		tmp |= CLR_FX;
1036 		tmp &= ~(SET_FX | AT91_UDP_FORCESTALL);
1037 		__raw_writel(tmp, ep->creg);
1038 		if (!list_empty(&ep->queue))
1039 			handle_ep(ep);
1040 		goto succeed;
1041 	}
1042 
1043 #undef w_value
1044 #undef w_index
1045 #undef w_length
1046 
1047 	/* pass request up to the gadget driver */
1048 	if (udc->driver) {
1049 		spin_unlock(&udc->lock);
1050 		status = udc->driver->setup(&udc->gadget, &pkt.r);
1051 		spin_lock(&udc->lock);
1052 	}
1053 	else
1054 		status = -ENODEV;
1055 	if (status < 0) {
1056 stall:
1057 		VDBG("req %02x.%02x protocol STALL; stat %d\n",
1058 				pkt.r.bRequestType, pkt.r.bRequest, status);
1059 		csr |= AT91_UDP_FORCESTALL;
1060 		__raw_writel(csr, creg);
1061 		udc->req_pending = 0;
1062 	}
1063 	return;
1064 
1065 succeed:
1066 	/* immediate successful (IN) STATUS after zero length DATA */
1067 	PACKET("ep0 in/status\n");
1068 write_in:
1069 	csr |= AT91_UDP_TXPKTRDY;
1070 	__raw_writel(csr, creg);
1071 	udc->req_pending = 0;
1072 }
1073 
1074 static void handle_ep0(struct at91_udc *udc)
1075 {
1076 	struct at91_ep		*ep0 = &udc->ep[0];
1077 	u32 __iomem		*creg = ep0->creg;
1078 	u32			csr = __raw_readl(creg);
1079 	struct at91_request	*req;
1080 
1081 	if (unlikely(csr & AT91_UDP_STALLSENT)) {
1082 		nuke(ep0, -EPROTO);
1083 		udc->req_pending = 0;
1084 		csr |= CLR_FX;
1085 		csr &= ~(SET_FX | AT91_UDP_STALLSENT | AT91_UDP_FORCESTALL);
1086 		__raw_writel(csr, creg);
1087 		VDBG("ep0 stalled\n");
1088 		csr = __raw_readl(creg);
1089 	}
1090 	if (csr & AT91_UDP_RXSETUP) {
1091 		nuke(ep0, 0);
1092 		udc->req_pending = 0;
1093 		handle_setup(udc, ep0, csr);
1094 		return;
1095 	}
1096 
1097 	if (list_empty(&ep0->queue))
1098 		req = NULL;
1099 	else
1100 		req = list_entry(ep0->queue.next, struct at91_request, queue);
1101 
1102 	/* host ACKed an IN packet that we sent */
1103 	if (csr & AT91_UDP_TXCOMP) {
1104 		csr |= CLR_FX;
1105 		csr &= ~(SET_FX | AT91_UDP_TXCOMP);
1106 
1107 		/* write more IN DATA? */
1108 		if (req && ep0->is_in) {
1109 			if (handle_ep(ep0))
1110 				udc->req_pending = 0;
1111 
1112 		/*
1113 		 * Ack after:
1114 		 *  - last IN DATA packet (including GET_STATUS)
1115 		 *  - IN/STATUS for OUT DATA
1116 		 *  - IN/STATUS for any zero-length DATA stage
1117 		 * except for the IN DATA case, the host should send
1118 		 * an OUT status later, which we'll ack.
1119 		 */
1120 		} else {
1121 			udc->req_pending = 0;
1122 			__raw_writel(csr, creg);
1123 
1124 			/*
1125 			 * SET_ADDRESS takes effect only after the STATUS
1126 			 * (to the original address) gets acked.
1127 			 */
1128 			if (udc->wait_for_addr_ack) {
1129 				u32	tmp;
1130 
1131 				at91_udp_write(udc, AT91_UDP_FADDR,
1132 						AT91_UDP_FEN | udc->addr);
1133 				tmp = at91_udp_read(udc, AT91_UDP_GLB_STAT);
1134 				tmp &= ~AT91_UDP_FADDEN;
1135 				if (udc->addr)
1136 					tmp |= AT91_UDP_FADDEN;
1137 				at91_udp_write(udc, AT91_UDP_GLB_STAT, tmp);
1138 
1139 				udc->wait_for_addr_ack = 0;
1140 				VDBG("address %d\n", udc->addr);
1141 			}
1142 		}
1143 	}
1144 
1145 	/* OUT packet arrived ... */
1146 	else if (csr & AT91_UDP_RX_DATA_BK0) {
1147 		csr |= CLR_FX;
1148 		csr &= ~(SET_FX | AT91_UDP_RX_DATA_BK0);
1149 
1150 		/* OUT DATA stage */
1151 		if (!ep0->is_in) {
1152 			if (req) {
1153 				if (handle_ep(ep0)) {
1154 					/* send IN/STATUS */
1155 					PACKET("ep0 in/status\n");
1156 					csr = __raw_readl(creg);
1157 					csr &= ~SET_FX;
1158 					csr |= CLR_FX | AT91_UDP_TXPKTRDY;
1159 					__raw_writel(csr, creg);
1160 					udc->req_pending = 0;
1161 				}
1162 			} else if (udc->req_pending) {
1163 				/*
1164 				 * AT91 hardware has a hard time with this
1165 				 * "deferred response" mode for control-OUT
1166 				 * transfers.  (For control-IN it's fine.)
1167 				 *
1168 				 * The normal solution leaves OUT data in the
1169 				 * fifo until the gadget driver is ready.
1170 				 * We couldn't do that here without disabling
1171 				 * the IRQ that tells about SETUP packets,
1172 				 * e.g. when the host gets impatient...
1173 				 *
1174 				 * Working around it by copying into a buffer
1175 				 * would almost be a non-deferred response,
1176 				 * except that it wouldn't permit reliable
1177 				 * stalling of the request.  Instead, demand
1178 				 * that gadget drivers not use this mode.
1179 				 */
1180 				DBG("no control-OUT deferred responses!\n");
1181 				__raw_writel(csr | AT91_UDP_FORCESTALL, creg);
1182 				udc->req_pending = 0;
1183 			}
1184 
1185 		/* STATUS stage for control-IN; ack.  */
1186 		} else {
1187 			PACKET("ep0 out/status ACK\n");
1188 			__raw_writel(csr, creg);
1189 
1190 			/* "early" status stage */
1191 			if (req)
1192 				done(ep0, req, 0);
1193 		}
1194 	}
1195 }
1196 
1197 static irqreturn_t at91_udc_irq(struct at91_udc *udc)
1198 {
1199 	u32			rescans = 5;
1200 	int			disable_clock = 0;
1201 	unsigned long		flags;
1202 
1203 	spin_lock_irqsave(&udc->lock, flags);
1204 
1205 	if (!udc->clocked) {
1206 		clk_on(udc);
1207 		disable_clock = 1;
1208 	}
1209 
1210 	while (rescans--) {
1211 		u32 status;
1212 
1213 		status = at91_udp_read(udc, AT91_UDP_ISR)
1214 			& at91_udp_read(udc, AT91_UDP_IMR);
1215 		if (!status)
1216 			break;
1217 
1218 		/* USB reset irq:  not maskable */
1219 		if (status & AT91_UDP_ENDBUSRES) {
1220 			at91_udp_write(udc, AT91_UDP_IDR, ~MINIMUS_INTERRUPTUS);
1221 			at91_udp_write(udc, AT91_UDP_IER, MINIMUS_INTERRUPTUS);
1222 			/* Atmel code clears this irq twice */
1223 			at91_udp_write(udc, AT91_UDP_ICR, AT91_UDP_ENDBUSRES);
1224 			at91_udp_write(udc, AT91_UDP_ICR, AT91_UDP_ENDBUSRES);
1225 			VDBG("end bus reset\n");
1226 			udc->addr = 0;
1227 			reset_gadget(udc);
1228 
1229 			/* enable ep0 */
1230 			at91_udp_write(udc, AT91_UDP_CSR(0),
1231 					AT91_UDP_EPEDS | AT91_UDP_EPTYPE_CTRL);
1232 			udc->gadget.speed = USB_SPEED_FULL;
1233 			udc->suspended = 0;
1234 			at91_udp_write(udc, AT91_UDP_IER, AT91_UDP_EP(0));
1235 
1236 			/*
1237 			 * NOTE:  this driver keeps clocks off unless the
1238 			 * USB host is present.  That saves power, but for
1239 			 * boards that don't support VBUS detection, both
1240 			 * clocks need to be active most of the time.
1241 			 */
1242 
1243 		/* host initiated suspend (3+ms bus idle) */
1244 		} else if (status & AT91_UDP_RXSUSP) {
1245 			at91_udp_write(udc, AT91_UDP_IDR, AT91_UDP_RXSUSP);
1246 			at91_udp_write(udc, AT91_UDP_IER, AT91_UDP_RXRSM);
1247 			at91_udp_write(udc, AT91_UDP_ICR, AT91_UDP_RXSUSP);
1248 			/* VDBG("bus suspend\n"); */
1249 			if (udc->suspended)
1250 				continue;
1251 			udc->suspended = 1;
1252 
1253 			/*
1254 			 * NOTE:  when suspending a VBUS-powered device, the
1255 			 * gadget driver should switch into slow clock mode
1256 			 * and then into standby to avoid drawing more than
1257 			 * 500uA power (2500uA for some high-power configs).
1258 			 */
1259 			if (udc->driver && udc->driver->suspend) {
1260 				spin_unlock(&udc->lock);
1261 				udc->driver->suspend(&udc->gadget);
1262 				spin_lock(&udc->lock);
1263 			}
1264 
1265 		/* host initiated resume */
1266 		} else if (status & AT91_UDP_RXRSM) {
1267 			at91_udp_write(udc, AT91_UDP_IDR, AT91_UDP_RXRSM);
1268 			at91_udp_write(udc, AT91_UDP_IER, AT91_UDP_RXSUSP);
1269 			at91_udp_write(udc, AT91_UDP_ICR, AT91_UDP_RXRSM);
1270 			/* VDBG("bus resume\n"); */
1271 			if (!udc->suspended)
1272 				continue;
1273 			udc->suspended = 0;
1274 
1275 			/*
1276 			 * NOTE:  for a VBUS-powered device, the gadget driver
1277 			 * would normally want to switch out of slow clock
1278 			 * mode into normal mode.
1279 			 */
1280 			if (udc->driver && udc->driver->resume) {
1281 				spin_unlock(&udc->lock);
1282 				udc->driver->resume(&udc->gadget);
1283 				spin_lock(&udc->lock);
1284 			}
1285 
1286 		/* endpoint IRQs are cleared by handling them */
1287 		} else {
1288 			int		i;
1289 			unsigned	mask = 1;
1290 			struct at91_ep	*ep = &udc->ep[1];
1291 
1292 			if (status & mask)
1293 				handle_ep0(udc);
1294 			for (i = 1; i < NUM_ENDPOINTS; i++) {
1295 				mask <<= 1;
1296 				if (status & mask)
1297 					handle_ep(ep);
1298 				ep++;
1299 			}
1300 		}
1301 	}
1302 
1303 	if (disable_clock)
1304 		clk_off(udc);
1305 
1306 	spin_unlock_irqrestore(&udc->lock, flags);
1307 
1308 	return IRQ_HANDLED;
1309 }
1310 
1311 /*-------------------------------------------------------------------------*/
1312 
1313 static int at91_start(struct usb_gadget *gadget,
1314 		struct usb_gadget_driver *driver)
1315 {
1316 	struct at91_udc *udc = controller;
1317 
1318 	udc->driver = driver;
1319 	udc->enabled = 1;
1320 	udc->selfpowered = 1;
1321 
1322 	return 0;
1323 }
1324 
1325 static int at91_stop(struct usb_gadget *gadget)
1326 {
1327 	struct at91_udc *udc = controller;
1328 	unsigned long	flags;
1329 
1330 	spin_lock_irqsave(&udc->lock, flags);
1331 	udc->enabled = 0;
1332 	at91_udp_write(udc, AT91_UDP_IDR, ~0);
1333 	spin_unlock_irqrestore(&udc->lock, flags);
1334 
1335 	udc->driver = NULL;
1336 
1337 	return 0;
1338 }
1339 
1340 /*-------------------------------------------------------------------------*/
1341 
1342 #if defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9G20)
1343 static int at91sam9260_udc_init(struct at91_udc *udc)
1344 {
1345 	struct at91_ep *ep;
1346 	int i;
1347 
1348 	for (i = 0; i < NUM_ENDPOINTS; i++) {
1349 		ep = &udc->ep[i];
1350 
1351 		switch (i) {
1352 		case 0 ... 3:
1353 			ep->maxpacket = 64;
1354 			break;
1355 		case 4 ... 5:
1356 			ep->maxpacket = 512;
1357 			break;
1358 		}
1359 	}
1360 
1361 	return 0;
1362 }
1363 
1364 static void at91sam9260_udc_pullup(struct at91_udc *udc, int is_on)
1365 {
1366 	u32 txvc = at91_udp_read(udc, AT91_UDP_TXVC);
1367 
1368 	if (is_on)
1369 		txvc |= AT91_UDP_TXVC_PUON;
1370 	else
1371 		txvc &= ~AT91_UDP_TXVC_PUON;
1372 
1373 	at91_udp_write(udc, AT91_UDP_TXVC, txvc);
1374 }
1375 
1376 static const struct at91_udc_caps at91sam9260_udc_caps = {
1377 	.init = at91sam9260_udc_init,
1378 	.pullup = at91sam9260_udc_pullup,
1379 };
1380 #endif
1381 
1382 #if defined(CONFIG_AT91SAM9261)
1383 static int at91sam9261_udc_init(struct at91_udc *udc)
1384 {
1385 	struct at91_ep *ep;
1386 	int i;
1387 
1388 	for (i = 0; i < NUM_ENDPOINTS; i++) {
1389 		ep = &udc->ep[i];
1390 
1391 		switch (i) {
1392 		case 0:
1393 			ep->maxpacket = 8;
1394 			break;
1395 		case 1 ... 3:
1396 			ep->maxpacket = 64;
1397 			break;
1398 		case 4 ... 5:
1399 			ep->maxpacket = 256;
1400 			break;
1401 		}
1402 	}
1403 
1404 	udc->matrix = (struct at91_matrix *)ATMEL_BASE_MATRIX;
1405 
1406 	if (IS_ERR(udc->matrix))
1407 		return PTR_ERR(udc->matrix);
1408 
1409 	return 0;
1410 }
1411 
1412 static void at91sam9261_udc_pullup(struct at91_udc *udc, int is_on)
1413 {
1414 	u32 usbpucr = 0;
1415 
1416 	usbpucr = readl(&udc->matrix->pucr);
1417 	if (is_on)
1418 		usbpucr |= AT91_MATRIX_USBPUCR_PUON;
1419 
1420 	writel(usbpucr, &udc->matrix->pucr);
1421 }
1422 
1423 static const struct at91_udc_caps at91sam9261_udc_caps = {
1424 	.init = at91sam9261_udc_init,
1425 	.pullup = at91sam9261_udc_pullup,
1426 };
1427 #endif
1428 
1429 int usb_gadget_handle_interrupts(int index)
1430 {
1431 	struct at91_udc *udc = controller;
1432 
1433 	return at91_udc_irq(udc);
1434 }
1435 
1436 int usb_gadget_register_driver(struct usb_gadget_driver *driver)
1437 {
1438 	struct at91_udc *udc = controller;
1439 	int ret;
1440 
1441 	if (!driver || !driver->bind || !driver->setup) {
1442 		printf("bad paramter\n");
1443 		return -EINVAL;
1444 	}
1445 
1446 	if (udc->driver) {
1447 		printf("UDC already has a gadget driver\n");
1448 		return -EBUSY;
1449 	}
1450 
1451 	at91_start(&udc->gadget, driver);
1452 
1453 	udc->driver = driver;
1454 
1455 	ret = driver->bind(&udc->gadget);
1456 	if (ret) {
1457 		pr_err("driver->bind() returned %d\n", ret);
1458 		udc->driver = NULL;
1459 	}
1460 
1461 	return ret;
1462 }
1463 
1464 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
1465 {
1466 	struct at91_udc *udc = controller;
1467 
1468 	if (!driver || !driver->unbind || !driver->disconnect) {
1469 		pr_err("bad paramter\n");
1470 		return -EINVAL;
1471 	}
1472 
1473 	driver->disconnect(&udc->gadget);
1474 	driver->unbind(&udc->gadget);
1475 	udc->driver = NULL;
1476 
1477 	at91_stop(&udc->gadget);
1478 
1479 	return 0;
1480 }
1481 
1482 int at91_udc_probe(struct at91_udc_data *pdata)
1483 {
1484 	struct at91_udc	*udc;
1485 	int		retval;
1486 	struct at91_ep	*ep;
1487 	int		i;
1488 
1489 	udc = kzalloc(sizeof(*udc), GFP_KERNEL);
1490 	if (!udc)
1491 		return -ENOMEM;
1492 
1493 	controller = udc;
1494 	memcpy(&udc->board, pdata, sizeof(struct at91_udc_data));
1495 	if (udc->board.vbus_pin) {
1496 		printf("%s: gpio vbus pin not supported yet.\n", __func__);
1497 		return -ENXIO;
1498 	} else {
1499 		DBG("no VBUS detection, assuming always-on\n");
1500 		udc->vbus = 1;
1501 	}
1502 
1503 #if defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9G20)
1504 	udc->caps = &at91sam9260_udc_caps;
1505 #endif
1506 
1507 	udc->enabled = 0;
1508 	spin_lock_init(&udc->lock);
1509 
1510 	udc->gadget.ops = &at91_udc_ops;
1511 	udc->gadget.ep0 = &udc->ep[0].ep;
1512 	udc->gadget.name = driver_name;
1513 
1514 	for (i = 0; i < NUM_ENDPOINTS; i++) {
1515 		ep = &udc->ep[i];
1516 		ep->ep.name = ep_names[i];
1517 		ep->ep.ops = &at91_ep_ops;
1518 		ep->udc = udc;
1519 		ep->int_mask = (1 << i);
1520 		if (i != 0 && i != 3)
1521 			ep->is_pingpong = 1;
1522 	}
1523 
1524 	udc->udp_baseaddr = (void *)udc->board.baseaddr;
1525 	if (IS_ERR(udc->udp_baseaddr))
1526 		return PTR_ERR(udc->udp_baseaddr);
1527 
1528 	if (udc->caps && udc->caps->init) {
1529 		retval = udc->caps->init(udc);
1530 		if (retval)
1531 			return retval;
1532 	}
1533 
1534 	udc_reinit(udc);
1535 
1536 	at91_udp_write(udc, AT91_UDP_TXVC, AT91_UDP_TXVC_TXVDIS);
1537 	at91_udp_write(udc, AT91_UDP_IDR, 0xffffffff);
1538 	/* Clear all pending interrupts - UDP may be used by bootloader. */
1539 	at91_udp_write(udc, AT91_UDP_ICR, 0xffffffff);
1540 
1541 	INFO("%s version %s\n", driver_name, DRIVER_VERSION);
1542 	return 0;
1543 }
1544