xref: /openbmc/linux/drivers/usb/gadget/udc/goku_udc.c (revision 65844828)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Toshiba TC86C001 ("Goku-S") USB Device Controller driver
4  *
5  * Copyright (C) 2000-2002 Lineo
6  *      by Stuart Lynne, Tom Rushworth, and Bruce Balden
7  * Copyright (C) 2002 Toshiba Corporation
8  * Copyright (C) 2003 MontaVista Software (source@mvista.com)
9  */
10 
11 /*
12  * This device has ep0 and three semi-configurable bulk/interrupt endpoints.
13  *
14  *  - Endpoint numbering is fixed: ep{1,2,3}-bulk
15  *  - Gadget drivers can choose ep maxpacket (8/16/32/64)
16  *  - Gadget drivers can choose direction (IN, OUT)
17  *  - DMA works with ep1 (OUT transfers) and ep2 (IN transfers).
18  */
19 
20 // #define	VERBOSE		/* extra debug messages (success too) */
21 // #define	USB_TRACE	/* packet-level success messages */
22 
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/pci.h>
26 #include <linux/delay.h>
27 #include <linux/ioport.h>
28 #include <linux/slab.h>
29 #include <linux/errno.h>
30 #include <linux/timer.h>
31 #include <linux/list.h>
32 #include <linux/interrupt.h>
33 #include <linux/proc_fs.h>
34 #include <linux/seq_file.h>
35 #include <linux/device.h>
36 #include <linux/usb/ch9.h>
37 #include <linux/usb/gadget.h>
38 #include <linux/prefetch.h>
39 
40 #include <asm/byteorder.h>
41 #include <asm/io.h>
42 #include <asm/irq.h>
43 #include <asm/unaligned.h>
44 
45 
46 #include "goku_udc.h"
47 
48 #define	DRIVER_DESC		"TC86C001 USB Device Controller"
49 #define	DRIVER_VERSION		"30-Oct 2003"
50 
51 static const char driver_name [] = "goku_udc";
52 static const char driver_desc [] = DRIVER_DESC;
53 
54 MODULE_AUTHOR("source@mvista.com");
55 MODULE_DESCRIPTION(DRIVER_DESC);
56 MODULE_LICENSE("GPL");
57 
58 
59 /*
60  * IN dma behaves ok under testing, though the IN-dma abort paths don't
61  * seem to behave quite as expected.  Used by default.
62  *
63  * OUT dma documents design problems handling the common "short packet"
64  * transfer termination policy; it couldn't be enabled by default, even
65  * if the OUT-dma abort problems had a resolution.
66  */
67 static unsigned use_dma = 1;
68 
69 #if 0
70 //#include <linux/moduleparam.h>
71 /* "modprobe goku_udc use_dma=1" etc
72  *	0 to disable dma
73  *	1 to use IN dma only (normal operation)
74  *	2 to use IN and OUT dma
75  */
76 module_param(use_dma, uint, S_IRUGO);
77 #endif
78 
79 /*-------------------------------------------------------------------------*/
80 
81 static void nuke(struct goku_ep *, int status);
82 
83 static inline void
84 command(struct goku_udc_regs __iomem *regs, int command, unsigned epnum)
85 {
86 	writel(COMMAND_EP(epnum) | command, &regs->Command);
87 	udelay(300);
88 }
89 
90 static int
91 goku_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
92 {
93 	struct goku_udc	*dev;
94 	struct goku_ep	*ep;
95 	u32		mode;
96 	u16		max;
97 	unsigned long	flags;
98 
99 	ep = container_of(_ep, struct goku_ep, ep);
100 	if (!_ep || !desc
101 			|| desc->bDescriptorType != USB_DT_ENDPOINT)
102 		return -EINVAL;
103 	dev = ep->dev;
104 	if (ep == &dev->ep[0])
105 		return -EINVAL;
106 	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)
107 		return -ESHUTDOWN;
108 	if (ep->num != usb_endpoint_num(desc))
109 		return -EINVAL;
110 
111 	switch (usb_endpoint_type(desc)) {
112 	case USB_ENDPOINT_XFER_BULK:
113 	case USB_ENDPOINT_XFER_INT:
114 		break;
115 	default:
116 		return -EINVAL;
117 	}
118 
119 	if ((readl(ep->reg_status) & EPxSTATUS_EP_MASK)
120 			!= EPxSTATUS_EP_INVALID)
121 		return -EBUSY;
122 
123 	/* enabling the no-toggle interrupt mode would need an api hook */
124 	mode = 0;
125 	max = get_unaligned_le16(&desc->wMaxPacketSize);
126 	switch (max) {
127 	case 64:
128 		mode++;
129 		fallthrough;
130 	case 32:
131 		mode++;
132 		fallthrough;
133 	case 16:
134 		mode++;
135 		fallthrough;
136 	case 8:
137 		mode <<= 3;
138 		break;
139 	default:
140 		return -EINVAL;
141 	}
142 	mode |= 2 << 1;		/* bulk, or intr-with-toggle */
143 
144 	/* ep1/ep2 dma direction is chosen early; it works in the other
145 	 * direction, with pio.  be cautious with out-dma.
146 	 */
147 	ep->is_in = usb_endpoint_dir_in(desc);
148 	if (ep->is_in) {
149 		mode |= 1;
150 		ep->dma = (use_dma != 0) && (ep->num == UDC_MSTRD_ENDPOINT);
151 	} else {
152 		ep->dma = (use_dma == 2) && (ep->num == UDC_MSTWR_ENDPOINT);
153 		if (ep->dma)
154 			DBG(dev, "%s out-dma hides short packets\n",
155 				ep->ep.name);
156 	}
157 
158 	spin_lock_irqsave(&ep->dev->lock, flags);
159 
160 	/* ep1 and ep2 can do double buffering and/or dma */
161 	if (ep->num < 3) {
162 		struct goku_udc_regs __iomem	*regs = ep->dev->regs;
163 		u32				tmp;
164 
165 		/* double buffer except (for now) with pio in */
166 		tmp = ((ep->dma || !ep->is_in)
167 				? 0x10	/* double buffered */
168 				: 0x11	/* single buffer */
169 			) << ep->num;
170 		tmp |= readl(&regs->EPxSingle);
171 		writel(tmp, &regs->EPxSingle);
172 
173 		tmp = (ep->dma ? 0x10/*dma*/ : 0x11/*pio*/) << ep->num;
174 		tmp |= readl(&regs->EPxBCS);
175 		writel(tmp, &regs->EPxBCS);
176 	}
177 	writel(mode, ep->reg_mode);
178 	command(ep->dev->regs, COMMAND_RESET, ep->num);
179 	ep->ep.maxpacket = max;
180 	ep->stopped = 0;
181 	ep->ep.desc = desc;
182 	spin_unlock_irqrestore(&ep->dev->lock, flags);
183 
184 	DBG(dev, "enable %s %s %s maxpacket %u\n", ep->ep.name,
185 		ep->is_in ? "IN" : "OUT",
186 		ep->dma ? "dma" : "pio",
187 		max);
188 
189 	return 0;
190 }
191 
192 static void ep_reset(struct goku_udc_regs __iomem *regs, struct goku_ep *ep)
193 {
194 	struct goku_udc		*dev = ep->dev;
195 
196 	if (regs) {
197 		command(regs, COMMAND_INVALID, ep->num);
198 		if (ep->num) {
199 			if (ep->num == UDC_MSTWR_ENDPOINT)
200 				dev->int_enable &= ~(INT_MSTWREND
201 							|INT_MSTWRTMOUT);
202 			else if (ep->num == UDC_MSTRD_ENDPOINT)
203 				dev->int_enable &= ~INT_MSTRDEND;
204 			dev->int_enable &= ~INT_EPxDATASET (ep->num);
205 		} else
206 			dev->int_enable &= ~INT_EP0;
207 		writel(dev->int_enable, &regs->int_enable);
208 		readl(&regs->int_enable);
209 		if (ep->num < 3) {
210 			struct goku_udc_regs __iomem	*r = ep->dev->regs;
211 			u32				tmp;
212 
213 			tmp = readl(&r->EPxSingle);
214 			tmp &= ~(0x11 << ep->num);
215 			writel(tmp, &r->EPxSingle);
216 
217 			tmp = readl(&r->EPxBCS);
218 			tmp &= ~(0x11 << ep->num);
219 			writel(tmp, &r->EPxBCS);
220 		}
221 		/* reset dma in case we're still using it */
222 		if (ep->dma) {
223 			u32	master;
224 
225 			master = readl(&regs->dma_master) & MST_RW_BITS;
226 			if (ep->num == UDC_MSTWR_ENDPOINT) {
227 				master &= ~MST_W_BITS;
228 				master |= MST_WR_RESET;
229 			} else {
230 				master &= ~MST_R_BITS;
231 				master |= MST_RD_RESET;
232 			}
233 			writel(master, &regs->dma_master);
234 		}
235 	}
236 
237 	usb_ep_set_maxpacket_limit(&ep->ep, MAX_FIFO_SIZE);
238 	ep->ep.desc = NULL;
239 	ep->stopped = 1;
240 	ep->irqs = 0;
241 	ep->dma = 0;
242 }
243 
244 static int goku_ep_disable(struct usb_ep *_ep)
245 {
246 	struct goku_ep	*ep;
247 	struct goku_udc	*dev;
248 	unsigned long	flags;
249 
250 	ep = container_of(_ep, struct goku_ep, ep);
251 	if (!_ep || !ep->ep.desc)
252 		return -ENODEV;
253 	dev = ep->dev;
254 	if (dev->ep0state == EP0_SUSPEND)
255 		return -EBUSY;
256 
257 	VDBG(dev, "disable %s\n", _ep->name);
258 
259 	spin_lock_irqsave(&dev->lock, flags);
260 	nuke(ep, -ESHUTDOWN);
261 	ep_reset(dev->regs, ep);
262 	spin_unlock_irqrestore(&dev->lock, flags);
263 
264 	return 0;
265 }
266 
267 /*-------------------------------------------------------------------------*/
268 
269 static struct usb_request *
270 goku_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
271 {
272 	struct goku_request	*req;
273 
274 	if (!_ep)
275 		return NULL;
276 	req = kzalloc(sizeof *req, gfp_flags);
277 	if (!req)
278 		return NULL;
279 
280 	INIT_LIST_HEAD(&req->queue);
281 	return &req->req;
282 }
283 
284 static void
285 goku_free_request(struct usb_ep *_ep, struct usb_request *_req)
286 {
287 	struct goku_request	*req;
288 
289 	if (!_ep || !_req)
290 		return;
291 
292 	req = container_of(_req, struct goku_request, req);
293 	WARN_ON(!list_empty(&req->queue));
294 	kfree(req);
295 }
296 
297 /*-------------------------------------------------------------------------*/
298 
299 static void
300 done(struct goku_ep *ep, struct goku_request *req, int status)
301 {
302 	struct goku_udc		*dev;
303 	unsigned		stopped = ep->stopped;
304 
305 	list_del_init(&req->queue);
306 
307 	if (likely(req->req.status == -EINPROGRESS))
308 		req->req.status = status;
309 	else
310 		status = req->req.status;
311 
312 	dev = ep->dev;
313 
314 	if (ep->dma)
315 		usb_gadget_unmap_request(&dev->gadget, &req->req, ep->is_in);
316 
317 #ifndef USB_TRACE
318 	if (status && status != -ESHUTDOWN)
319 #endif
320 		VDBG(dev, "complete %s req %p stat %d len %u/%u\n",
321 			ep->ep.name, &req->req, status,
322 			req->req.actual, req->req.length);
323 
324 	/* don't modify queue heads during completion callback */
325 	ep->stopped = 1;
326 	spin_unlock(&dev->lock);
327 	usb_gadget_giveback_request(&ep->ep, &req->req);
328 	spin_lock(&dev->lock);
329 	ep->stopped = stopped;
330 }
331 
332 /*-------------------------------------------------------------------------*/
333 
334 static inline int
335 write_packet(u32 __iomem *fifo, u8 *buf, struct goku_request *req, unsigned max)
336 {
337 	unsigned	length, count;
338 
339 	length = min(req->req.length - req->req.actual, max);
340 	req->req.actual += length;
341 
342 	count = length;
343 	while (likely(count--))
344 		writel(*buf++, fifo);
345 	return length;
346 }
347 
348 // return:  0 = still running, 1 = completed, negative = errno
349 static int write_fifo(struct goku_ep *ep, struct goku_request *req)
350 {
351 	struct goku_udc	*dev = ep->dev;
352 	u32		tmp;
353 	u8		*buf;
354 	unsigned	count;
355 	int		is_last;
356 
357 	tmp = readl(&dev->regs->DataSet);
358 	buf = req->req.buf + req->req.actual;
359 	prefetch(buf);
360 
361 	dev = ep->dev;
362 	if (unlikely(ep->num == 0 && dev->ep0state != EP0_IN))
363 		return -EL2HLT;
364 
365 	/* NOTE:  just single-buffered PIO-IN for now.  */
366 	if (unlikely((tmp & DATASET_A(ep->num)) != 0))
367 		return 0;
368 
369 	/* clear our "packet available" irq */
370 	if (ep->num != 0)
371 		writel(~INT_EPxDATASET(ep->num), &dev->regs->int_status);
372 
373 	count = write_packet(ep->reg_fifo, buf, req, ep->ep.maxpacket);
374 
375 	/* last packet often short (sometimes a zlp, especially on ep0) */
376 	if (unlikely(count != ep->ep.maxpacket)) {
377 		writel(~(1<<ep->num), &dev->regs->EOP);
378 		if (ep->num == 0) {
379 			dev->ep[0].stopped = 1;
380 			dev->ep0state = EP0_STATUS;
381 		}
382 		is_last = 1;
383 	} else {
384 		if (likely(req->req.length != req->req.actual)
385 				|| req->req.zero)
386 			is_last = 0;
387 		else
388 			is_last = 1;
389 	}
390 #if 0		/* printk seemed to trash is_last...*/
391 //#ifdef USB_TRACE
392 	VDBG(dev, "wrote %s %u bytes%s IN %u left %p\n",
393 		ep->ep.name, count, is_last ? "/last" : "",
394 		req->req.length - req->req.actual, req);
395 #endif
396 
397 	/* requests complete when all IN data is in the FIFO,
398 	 * or sometimes later, if a zlp was needed.
399 	 */
400 	if (is_last) {
401 		done(ep, req, 0);
402 		return 1;
403 	}
404 
405 	return 0;
406 }
407 
408 static int read_fifo(struct goku_ep *ep, struct goku_request *req)
409 {
410 	struct goku_udc_regs __iomem	*regs;
411 	u32				size, set;
412 	u8				*buf;
413 	unsigned			bufferspace, is_short, dbuff;
414 
415 	regs = ep->dev->regs;
416 top:
417 	buf = req->req.buf + req->req.actual;
418 	prefetchw(buf);
419 
420 	if (unlikely(ep->num == 0 && ep->dev->ep0state != EP0_OUT))
421 		return -EL2HLT;
422 
423 	dbuff = (ep->num == 1 || ep->num == 2);
424 	do {
425 		/* ack dataset irq matching the status we'll handle */
426 		if (ep->num != 0)
427 			writel(~INT_EPxDATASET(ep->num), &regs->int_status);
428 
429 		set = readl(&regs->DataSet) & DATASET_AB(ep->num);
430 		size = readl(&regs->EPxSizeLA[ep->num]);
431 		bufferspace = req->req.length - req->req.actual;
432 
433 		/* usually do nothing without an OUT packet */
434 		if (likely(ep->num != 0 || bufferspace != 0)) {
435 			if (unlikely(set == 0))
436 				break;
437 			/* use ep1/ep2 double-buffering for OUT */
438 			if (!(size & PACKET_ACTIVE))
439 				size = readl(&regs->EPxSizeLB[ep->num]);
440 			if (!(size & PACKET_ACTIVE))	/* "can't happen" */
441 				break;
442 			size &= DATASIZE;	/* EPxSizeH == 0 */
443 
444 		/* ep0out no-out-data case for set_config, etc */
445 		} else
446 			size = 0;
447 
448 		/* read all bytes from this packet */
449 		req->req.actual += size;
450 		is_short = (size < ep->ep.maxpacket);
451 #ifdef USB_TRACE
452 		VDBG(ep->dev, "read %s %u bytes%s OUT req %p %u/%u\n",
453 			ep->ep.name, size, is_short ? "/S" : "",
454 			req, req->req.actual, req->req.length);
455 #endif
456 		while (likely(size-- != 0)) {
457 			u8	byte = (u8) readl(ep->reg_fifo);
458 
459 			if (unlikely(bufferspace == 0)) {
460 				/* this happens when the driver's buffer
461 				 * is smaller than what the host sent.
462 				 * discard the extra data in this packet.
463 				 */
464 				if (req->req.status != -EOVERFLOW)
465 					DBG(ep->dev, "%s overflow %u\n",
466 						ep->ep.name, size);
467 				req->req.status = -EOVERFLOW;
468 			} else {
469 				*buf++ = byte;
470 				bufferspace--;
471 			}
472 		}
473 
474 		/* completion */
475 		if (unlikely(is_short || req->req.actual == req->req.length)) {
476 			if (unlikely(ep->num == 0)) {
477 				/* non-control endpoints now usable? */
478 				if (ep->dev->req_config)
479 					writel(ep->dev->configured
480 							? USBSTATE_CONFIGURED
481 							: 0,
482 						&regs->UsbState);
483 				/* ep0out status stage */
484 				writel(~(1<<0), &regs->EOP);
485 				ep->stopped = 1;
486 				ep->dev->ep0state = EP0_STATUS;
487 			}
488 			done(ep, req, 0);
489 
490 			/* empty the second buffer asap */
491 			if (dbuff && !list_empty(&ep->queue)) {
492 				req = list_entry(ep->queue.next,
493 						struct goku_request, queue);
494 				goto top;
495 			}
496 			return 1;
497 		}
498 	} while (dbuff);
499 	return 0;
500 }
501 
502 static inline void
503 pio_irq_enable(struct goku_udc *dev,
504 		struct goku_udc_regs __iomem *regs, int epnum)
505 {
506 	dev->int_enable |= INT_EPxDATASET (epnum);
507 	writel(dev->int_enable, &regs->int_enable);
508 	/* write may still be posted */
509 }
510 
511 static inline void
512 pio_irq_disable(struct goku_udc *dev,
513 		struct goku_udc_regs __iomem *regs, int epnum)
514 {
515 	dev->int_enable &= ~INT_EPxDATASET (epnum);
516 	writel(dev->int_enable, &regs->int_enable);
517 	/* write may still be posted */
518 }
519 
520 static inline void
521 pio_advance(struct goku_ep *ep)
522 {
523 	struct goku_request	*req;
524 
525 	if (unlikely(list_empty (&ep->queue)))
526 		return;
527 	req = list_entry(ep->queue.next, struct goku_request, queue);
528 	(ep->is_in ? write_fifo : read_fifo)(ep, req);
529 }
530 
531 
532 /*-------------------------------------------------------------------------*/
533 
534 // return:  0 = q running, 1 = q stopped, negative = errno
535 static int start_dma(struct goku_ep *ep, struct goku_request *req)
536 {
537 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
538 	u32				master;
539 	u32				start = req->req.dma;
540 	u32				end = start + req->req.length - 1;
541 
542 	master = readl(&regs->dma_master) & MST_RW_BITS;
543 
544 	/* re-init the bits affecting IN dma; careful with zlps */
545 	if (likely(ep->is_in)) {
546 		if (unlikely(master & MST_RD_ENA)) {
547 			DBG (ep->dev, "start, IN active dma %03x!!\n",
548 				master);
549 //			return -EL2HLT;
550 		}
551 		writel(end, &regs->in_dma_end);
552 		writel(start, &regs->in_dma_start);
553 
554 		master &= ~MST_R_BITS;
555 		if (unlikely(req->req.length == 0))
556 			master |= MST_RD_ENA | MST_RD_EOPB;
557 		else if ((req->req.length % ep->ep.maxpacket) != 0
558 					|| req->req.zero)
559 			master |= MST_RD_ENA | MST_EOPB_ENA;
560 		else
561 			master |= MST_RD_ENA | MST_EOPB_DIS;
562 
563 		ep->dev->int_enable |= INT_MSTRDEND;
564 
565 	/* Goku DMA-OUT merges short packets, which plays poorly with
566 	 * protocols where short packets mark the transfer boundaries.
567 	 * The chip supports a nonstandard policy with INT_MSTWRTMOUT,
568 	 * ending transfers after 3 SOFs; we don't turn it on.
569 	 */
570 	} else {
571 		if (unlikely(master & MST_WR_ENA)) {
572 			DBG (ep->dev, "start, OUT active dma %03x!!\n",
573 				master);
574 //			return -EL2HLT;
575 		}
576 		writel(end, &regs->out_dma_end);
577 		writel(start, &regs->out_dma_start);
578 
579 		master &= ~MST_W_BITS;
580 		master |= MST_WR_ENA | MST_TIMEOUT_DIS;
581 
582 		ep->dev->int_enable |= INT_MSTWREND|INT_MSTWRTMOUT;
583 	}
584 
585 	writel(master, &regs->dma_master);
586 	writel(ep->dev->int_enable, &regs->int_enable);
587 	return 0;
588 }
589 
590 static void dma_advance(struct goku_udc *dev, struct goku_ep *ep)
591 {
592 	struct goku_request		*req;
593 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
594 	u32				master;
595 
596 	master = readl(&regs->dma_master);
597 
598 	if (unlikely(list_empty(&ep->queue))) {
599 stop:
600 		if (ep->is_in)
601 			dev->int_enable &= ~INT_MSTRDEND;
602 		else
603 			dev->int_enable &= ~(INT_MSTWREND|INT_MSTWRTMOUT);
604 		writel(dev->int_enable, &regs->int_enable);
605 		return;
606 	}
607 	req = list_entry(ep->queue.next, struct goku_request, queue);
608 
609 	/* normal hw dma completion (not abort) */
610 	if (likely(ep->is_in)) {
611 		if (unlikely(master & MST_RD_ENA))
612 			return;
613 		req->req.actual = readl(&regs->in_dma_current);
614 	} else {
615 		if (unlikely(master & MST_WR_ENA))
616 			return;
617 
618 		/* hardware merges short packets, and also hides packet
619 		 * overruns.  a partial packet MAY be in the fifo here.
620 		 */
621 		req->req.actual = readl(&regs->out_dma_current);
622 	}
623 	req->req.actual -= req->req.dma;
624 	req->req.actual++;
625 
626 #ifdef USB_TRACE
627 	VDBG(dev, "done %s %s dma, %u/%u bytes, req %p\n",
628 		ep->ep.name, ep->is_in ? "IN" : "OUT",
629 		req->req.actual, req->req.length, req);
630 #endif
631 	done(ep, req, 0);
632 	if (list_empty(&ep->queue))
633 		goto stop;
634 	req = list_entry(ep->queue.next, struct goku_request, queue);
635 	(void) start_dma(ep, req);
636 }
637 
638 static void abort_dma(struct goku_ep *ep, int status)
639 {
640 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
641 	struct goku_request		*req;
642 	u32				curr, master;
643 
644 	/* NAK future host requests, hoping the implicit delay lets the
645 	 * dma engine finish reading (or writing) its latest packet and
646 	 * empty the dma buffer (up to 16 bytes).
647 	 *
648 	 * This avoids needing to clean up a partial packet in the fifo;
649 	 * we can't do that for IN without side effects to HALT and TOGGLE.
650 	 */
651 	command(regs, COMMAND_FIFO_DISABLE, ep->num);
652 	req = list_entry(ep->queue.next, struct goku_request, queue);
653 	master = readl(&regs->dma_master) & MST_RW_BITS;
654 
655 	/* FIXME using these resets isn't usably documented. this may
656 	 * not work unless it's followed by disabling the endpoint.
657 	 *
658 	 * FIXME the OUT reset path doesn't even behave consistently.
659 	 */
660 	if (ep->is_in) {
661 		if (unlikely((readl(&regs->dma_master) & MST_RD_ENA) == 0))
662 			goto finished;
663 		curr = readl(&regs->in_dma_current);
664 
665 		writel(curr, &regs->in_dma_end);
666 		writel(curr, &regs->in_dma_start);
667 
668 		master &= ~MST_R_BITS;
669 		master |= MST_RD_RESET;
670 		writel(master, &regs->dma_master);
671 
672 		if (readl(&regs->dma_master) & MST_RD_ENA)
673 			DBG(ep->dev, "IN dma active after reset!\n");
674 
675 	} else {
676 		if (unlikely((readl(&regs->dma_master) & MST_WR_ENA) == 0))
677 			goto finished;
678 		curr = readl(&regs->out_dma_current);
679 
680 		writel(curr, &regs->out_dma_end);
681 		writel(curr, &regs->out_dma_start);
682 
683 		master &= ~MST_W_BITS;
684 		master |= MST_WR_RESET;
685 		writel(master, &regs->dma_master);
686 
687 		if (readl(&regs->dma_master) & MST_WR_ENA)
688 			DBG(ep->dev, "OUT dma active after reset!\n");
689 	}
690 	req->req.actual = (curr - req->req.dma) + 1;
691 	req->req.status = status;
692 
693 	VDBG(ep->dev, "%s %s %s %d/%d\n", __func__, ep->ep.name,
694 		ep->is_in ? "IN" : "OUT",
695 		req->req.actual, req->req.length);
696 
697 	command(regs, COMMAND_FIFO_ENABLE, ep->num);
698 
699 	return;
700 
701 finished:
702 	/* dma already completed; no abort needed */
703 	command(regs, COMMAND_FIFO_ENABLE, ep->num);
704 	req->req.actual = req->req.length;
705 	req->req.status = 0;
706 }
707 
708 /*-------------------------------------------------------------------------*/
709 
710 static int
711 goku_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags)
712 {
713 	struct goku_request	*req;
714 	struct goku_ep		*ep;
715 	struct goku_udc		*dev;
716 	unsigned long		flags;
717 	int			status;
718 
719 	/* always require a cpu-view buffer so pio works */
720 	req = container_of(_req, struct goku_request, req);
721 	if (unlikely(!_req || !_req->complete
722 			|| !_req->buf || !list_empty(&req->queue)))
723 		return -EINVAL;
724 	ep = container_of(_ep, struct goku_ep, ep);
725 	if (unlikely(!_ep || (!ep->ep.desc && ep->num != 0)))
726 		return -EINVAL;
727 	dev = ep->dev;
728 	if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN))
729 		return -ESHUTDOWN;
730 
731 	/* can't touch registers when suspended */
732 	if (dev->ep0state == EP0_SUSPEND)
733 		return -EBUSY;
734 
735 	/* set up dma mapping in case the caller didn't */
736 	if (ep->dma) {
737 		status = usb_gadget_map_request(&dev->gadget, &req->req,
738 				ep->is_in);
739 		if (status)
740 			return status;
741 	}
742 
743 #ifdef USB_TRACE
744 	VDBG(dev, "%s queue req %p, len %u buf %p\n",
745 			_ep->name, _req, _req->length, _req->buf);
746 #endif
747 
748 	spin_lock_irqsave(&dev->lock, flags);
749 
750 	_req->status = -EINPROGRESS;
751 	_req->actual = 0;
752 
753 	/* for ep0 IN without premature status, zlp is required and
754 	 * writing EOP starts the status stage (OUT).
755 	 */
756 	if (unlikely(ep->num == 0 && ep->is_in))
757 		_req->zero = 1;
758 
759 	/* kickstart this i/o queue? */
760 	status = 0;
761 	if (list_empty(&ep->queue) && likely(!ep->stopped)) {
762 		/* dma:  done after dma completion IRQ (or error)
763 		 * pio:  done after last fifo operation
764 		 */
765 		if (ep->dma)
766 			status = start_dma(ep, req);
767 		else
768 			status = (ep->is_in ? write_fifo : read_fifo)(ep, req);
769 
770 		if (unlikely(status != 0)) {
771 			if (status > 0)
772 				status = 0;
773 			req = NULL;
774 		}
775 
776 	} /* else pio or dma irq handler advances the queue. */
777 
778 	if (likely(req != NULL))
779 		list_add_tail(&req->queue, &ep->queue);
780 
781 	if (likely(!list_empty(&ep->queue))
782 			&& likely(ep->num != 0)
783 			&& !ep->dma
784 			&& !(dev->int_enable & INT_EPxDATASET (ep->num)))
785 		pio_irq_enable(dev, dev->regs, ep->num);
786 
787 	spin_unlock_irqrestore(&dev->lock, flags);
788 
789 	/* pci writes may still be posted */
790 	return status;
791 }
792 
793 /* dequeue ALL requests */
794 static void nuke(struct goku_ep *ep, int status)
795 {
796 	struct goku_request	*req;
797 
798 	ep->stopped = 1;
799 	if (list_empty(&ep->queue))
800 		return;
801 	if (ep->dma)
802 		abort_dma(ep, status);
803 	while (!list_empty(&ep->queue)) {
804 		req = list_entry(ep->queue.next, struct goku_request, queue);
805 		done(ep, req, status);
806 	}
807 }
808 
809 /* dequeue JUST ONE request */
810 static int goku_dequeue(struct usb_ep *_ep, struct usb_request *_req)
811 {
812 	struct goku_request	*req = NULL, *iter;
813 	struct goku_ep		*ep;
814 	struct goku_udc		*dev;
815 	unsigned long		flags;
816 
817 	ep = container_of(_ep, struct goku_ep, ep);
818 	if (!_ep || !_req || (!ep->ep.desc && ep->num != 0))
819 		return -EINVAL;
820 	dev = ep->dev;
821 	if (!dev->driver)
822 		return -ESHUTDOWN;
823 
824 	/* we can't touch (dma) registers when suspended */
825 	if (dev->ep0state == EP0_SUSPEND)
826 		return -EBUSY;
827 
828 	VDBG(dev, "%s %s %s %s %p\n", __func__, _ep->name,
829 		ep->is_in ? "IN" : "OUT",
830 		ep->dma ? "dma" : "pio",
831 		_req);
832 
833 	spin_lock_irqsave(&dev->lock, flags);
834 
835 	/* make sure it's actually queued on this endpoint */
836 	list_for_each_entry(iter, &ep->queue, queue) {
837 		if (&iter->req != _req)
838 			continue;
839 		req = iter;
840 		break;
841 	}
842 	if (!req) {
843 		spin_unlock_irqrestore (&dev->lock, flags);
844 		return -EINVAL;
845 	}
846 
847 	if (ep->dma && ep->queue.next == &req->queue && !ep->stopped) {
848 		abort_dma(ep, -ECONNRESET);
849 		done(ep, req, -ECONNRESET);
850 		dma_advance(dev, ep);
851 	} else if (!list_empty(&req->queue))
852 		done(ep, req, -ECONNRESET);
853 	else
854 		req = NULL;
855 	spin_unlock_irqrestore(&dev->lock, flags);
856 
857 	return req ? 0 : -EOPNOTSUPP;
858 }
859 
860 /*-------------------------------------------------------------------------*/
861 
862 static void goku_clear_halt(struct goku_ep *ep)
863 {
864 	// assert (ep->num !=0)
865 	VDBG(ep->dev, "%s clear halt\n", ep->ep.name);
866 	command(ep->dev->regs, COMMAND_SETDATA0, ep->num);
867 	command(ep->dev->regs, COMMAND_STALL_CLEAR, ep->num);
868 	if (ep->stopped) {
869 		ep->stopped = 0;
870 		if (ep->dma) {
871 			struct goku_request	*req;
872 
873 			if (list_empty(&ep->queue))
874 				return;
875 			req = list_entry(ep->queue.next, struct goku_request,
876 						queue);
877 			(void) start_dma(ep, req);
878 		} else
879 			pio_advance(ep);
880 	}
881 }
882 
883 static int goku_set_halt(struct usb_ep *_ep, int value)
884 {
885 	struct goku_ep	*ep;
886 	unsigned long	flags;
887 	int		retval = 0;
888 
889 	if (!_ep)
890 		return -ENODEV;
891 	ep = container_of (_ep, struct goku_ep, ep);
892 
893 	if (ep->num == 0) {
894 		if (value) {
895 			ep->dev->ep0state = EP0_STALL;
896 			ep->dev->ep[0].stopped = 1;
897 		} else
898 			return -EINVAL;
899 
900 	/* don't change EPxSTATUS_EP_INVALID to READY */
901 	} else if (!ep->ep.desc) {
902 		DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
903 		return -EINVAL;
904 	}
905 
906 	spin_lock_irqsave(&ep->dev->lock, flags);
907 	if (!list_empty(&ep->queue))
908 		retval = -EAGAIN;
909 	else if (ep->is_in && value
910 			/* data in (either) packet buffer? */
911 			&& (readl(&ep->dev->regs->DataSet)
912 					& DATASET_AB(ep->num)))
913 		retval = -EAGAIN;
914 	else if (!value)
915 		goku_clear_halt(ep);
916 	else {
917 		ep->stopped = 1;
918 		VDBG(ep->dev, "%s set halt\n", ep->ep.name);
919 		command(ep->dev->regs, COMMAND_STALL, ep->num);
920 		readl(ep->reg_status);
921 	}
922 	spin_unlock_irqrestore(&ep->dev->lock, flags);
923 	return retval;
924 }
925 
926 static int goku_fifo_status(struct usb_ep *_ep)
927 {
928 	struct goku_ep			*ep;
929 	struct goku_udc_regs __iomem	*regs;
930 	u32				size;
931 
932 	if (!_ep)
933 		return -ENODEV;
934 	ep = container_of(_ep, struct goku_ep, ep);
935 
936 	/* size is only reported sanely for OUT */
937 	if (ep->is_in)
938 		return -EOPNOTSUPP;
939 
940 	/* ignores 16-byte dma buffer; SizeH == 0 */
941 	regs = ep->dev->regs;
942 	size = readl(&regs->EPxSizeLA[ep->num]) & DATASIZE;
943 	size += readl(&regs->EPxSizeLB[ep->num]) & DATASIZE;
944 	VDBG(ep->dev, "%s %s %u\n", __func__, ep->ep.name, size);
945 	return size;
946 }
947 
948 static void goku_fifo_flush(struct usb_ep *_ep)
949 {
950 	struct goku_ep			*ep;
951 	struct goku_udc_regs __iomem	*regs;
952 	u32				size;
953 
954 	if (!_ep)
955 		return;
956 	ep = container_of(_ep, struct goku_ep, ep);
957 	VDBG(ep->dev, "%s %s\n", __func__, ep->ep.name);
958 
959 	/* don't change EPxSTATUS_EP_INVALID to READY */
960 	if (!ep->ep.desc && ep->num != 0) {
961 		DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
962 		return;
963 	}
964 
965 	regs = ep->dev->regs;
966 	size = readl(&regs->EPxSizeLA[ep->num]);
967 	size &= DATASIZE;
968 
969 	/* Non-desirable behavior:  FIFO_CLEAR also clears the
970 	 * endpoint halt feature.  For OUT, we _could_ just read
971 	 * the bytes out (PIO, if !ep->dma); for in, no choice.
972 	 */
973 	if (size)
974 		command(regs, COMMAND_FIFO_CLEAR, ep->num);
975 }
976 
977 static const struct usb_ep_ops goku_ep_ops = {
978 	.enable		= goku_ep_enable,
979 	.disable	= goku_ep_disable,
980 
981 	.alloc_request	= goku_alloc_request,
982 	.free_request	= goku_free_request,
983 
984 	.queue		= goku_queue,
985 	.dequeue	= goku_dequeue,
986 
987 	.set_halt	= goku_set_halt,
988 	.fifo_status	= goku_fifo_status,
989 	.fifo_flush	= goku_fifo_flush,
990 };
991 
992 /*-------------------------------------------------------------------------*/
993 
994 static int goku_get_frame(struct usb_gadget *_gadget)
995 {
996 	return -EOPNOTSUPP;
997 }
998 
999 static struct usb_ep *goku_match_ep(struct usb_gadget *g,
1000 		struct usb_endpoint_descriptor *desc,
1001 		struct usb_ss_ep_comp_descriptor *ep_comp)
1002 {
1003 	struct goku_udc	*dev = to_goku_udc(g);
1004 	struct usb_ep *ep;
1005 
1006 	switch (usb_endpoint_type(desc)) {
1007 	case USB_ENDPOINT_XFER_INT:
1008 		/* single buffering is enough */
1009 		ep = &dev->ep[3].ep;
1010 		if (usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1011 			return ep;
1012 		break;
1013 	case USB_ENDPOINT_XFER_BULK:
1014 		if (usb_endpoint_dir_in(desc)) {
1015 			/* DMA may be available */
1016 			ep = &dev->ep[2].ep;
1017 			if (usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1018 				return ep;
1019 		}
1020 		break;
1021 	default:
1022 		/* nothing */ ;
1023 	}
1024 
1025 	return NULL;
1026 }
1027 
1028 static int goku_udc_start(struct usb_gadget *g,
1029 		struct usb_gadget_driver *driver);
1030 static int goku_udc_stop(struct usb_gadget *g);
1031 
1032 static const struct usb_gadget_ops goku_ops = {
1033 	.get_frame	= goku_get_frame,
1034 	.udc_start	= goku_udc_start,
1035 	.udc_stop	= goku_udc_stop,
1036 	.match_ep	= goku_match_ep,
1037 	// no remote wakeup
1038 	// not selfpowered
1039 };
1040 
1041 /*-------------------------------------------------------------------------*/
1042 
1043 static inline const char *dmastr(void)
1044 {
1045 	if (use_dma == 0)
1046 		return "(dma disabled)";
1047 	else if (use_dma == 2)
1048 		return "(dma IN and OUT)";
1049 	else
1050 		return "(dma IN)";
1051 }
1052 
1053 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1054 
1055 static const char proc_node_name [] = "driver/udc";
1056 
1057 #define FOURBITS "%s%s%s%s"
1058 #define EIGHTBITS FOURBITS FOURBITS
1059 
1060 static void dump_intmask(struct seq_file *m, const char *label, u32 mask)
1061 {
1062 	/* int_status is the same format ... */
1063 	seq_printf(m, "%s %05X =" FOURBITS EIGHTBITS EIGHTBITS "\n",
1064 		   label, mask,
1065 		   (mask & INT_PWRDETECT) ? " power" : "",
1066 		   (mask & INT_SYSERROR) ? " sys" : "",
1067 		   (mask & INT_MSTRDEND) ? " in-dma" : "",
1068 		   (mask & INT_MSTWRTMOUT) ? " wrtmo" : "",
1069 
1070 		   (mask & INT_MSTWREND) ? " out-dma" : "",
1071 		   (mask & INT_MSTWRSET) ? " wrset" : "",
1072 		   (mask & INT_ERR) ? " err" : "",
1073 		   (mask & INT_SOF) ? " sof" : "",
1074 
1075 		   (mask & INT_EP3NAK) ? " ep3nak" : "",
1076 		   (mask & INT_EP2NAK) ? " ep2nak" : "",
1077 		   (mask & INT_EP1NAK) ? " ep1nak" : "",
1078 		   (mask & INT_EP3DATASET) ? " ep3" : "",
1079 
1080 		   (mask & INT_EP2DATASET) ? " ep2" : "",
1081 		   (mask & INT_EP1DATASET) ? " ep1" : "",
1082 		   (mask & INT_STATUSNAK) ? " ep0snak" : "",
1083 		   (mask & INT_STATUS) ? " ep0status" : "",
1084 
1085 		   (mask & INT_SETUP) ? " setup" : "",
1086 		   (mask & INT_ENDPOINT0) ? " ep0" : "",
1087 		   (mask & INT_USBRESET) ? " reset" : "",
1088 		   (mask & INT_SUSPEND) ? " suspend" : "");
1089 }
1090 
1091 static const char *udc_ep_state(enum ep0state state)
1092 {
1093 	switch (state) {
1094 	case EP0_DISCONNECT:
1095 		return "ep0_disconnect";
1096 	case EP0_IDLE:
1097 		return "ep0_idle";
1098 	case EP0_IN:
1099 		return "ep0_in";
1100 	case EP0_OUT:
1101 		return "ep0_out";
1102 	case EP0_STATUS:
1103 		return "ep0_status";
1104 	case EP0_STALL:
1105 		return "ep0_stall";
1106 	case EP0_SUSPEND:
1107 		return "ep0_suspend";
1108 	}
1109 
1110 	return "ep0_?";
1111 }
1112 
1113 static const char *udc_ep_status(u32 status)
1114 {
1115 	switch (status & EPxSTATUS_EP_MASK) {
1116 	case EPxSTATUS_EP_READY:
1117 		return "ready";
1118 	case EPxSTATUS_EP_DATAIN:
1119 		return "packet";
1120 	case EPxSTATUS_EP_FULL:
1121 		return "full";
1122 	case EPxSTATUS_EP_TX_ERR:	/* host will retry */
1123 		return "tx_err";
1124 	case EPxSTATUS_EP_RX_ERR:
1125 		return "rx_err";
1126 	case EPxSTATUS_EP_BUSY:		/* ep0 only */
1127 		return "busy";
1128 	case EPxSTATUS_EP_STALL:
1129 		return "stall";
1130 	case EPxSTATUS_EP_INVALID:	/* these "can't happen" */
1131 		return "invalid";
1132 	}
1133 
1134 	return "?";
1135 }
1136 
1137 static int udc_proc_read(struct seq_file *m, void *v)
1138 {
1139 	struct goku_udc			*dev = m->private;
1140 	struct goku_udc_regs __iomem	*regs = dev->regs;
1141 	unsigned long			flags;
1142 	int				i, is_usb_connected;
1143 	u32				tmp;
1144 
1145 	local_irq_save(flags);
1146 
1147 	/* basic device status */
1148 	tmp = readl(&regs->power_detect);
1149 	is_usb_connected = tmp & PW_DETECT;
1150 	seq_printf(m,
1151 		   "%s - %s\n"
1152 		   "%s version: %s %s\n"
1153 		   "Gadget driver: %s\n"
1154 		   "Host %s, %s\n"
1155 		   "\n",
1156 		   pci_name(dev->pdev), driver_desc,
1157 		   driver_name, DRIVER_VERSION, dmastr(),
1158 		   dev->driver ? dev->driver->driver.name : "(none)",
1159 		   is_usb_connected
1160 			   ? ((tmp & PW_PULLUP) ? "full speed" : "powered")
1161 			   : "disconnected",
1162 		   udc_ep_state(dev->ep0state));
1163 
1164 	dump_intmask(m, "int_status", readl(&regs->int_status));
1165 	dump_intmask(m, "int_enable", readl(&regs->int_enable));
1166 
1167 	if (!is_usb_connected || !dev->driver || (tmp & PW_PULLUP) == 0)
1168 		goto done;
1169 
1170 	/* registers for (active) device and ep0 */
1171 	seq_printf(m, "\nirqs %lu\ndataset %02x single.bcs %02x.%02x state %x addr %u\n",
1172 		   dev->irqs, readl(&regs->DataSet),
1173 		   readl(&regs->EPxSingle), readl(&regs->EPxBCS),
1174 		   readl(&regs->UsbState),
1175 		   readl(&regs->address));
1176 	if (seq_has_overflowed(m))
1177 		goto done;
1178 
1179 	tmp = readl(&regs->dma_master);
1180 	seq_printf(m, "dma %03X =" EIGHTBITS "%s %s\n",
1181 		   tmp,
1182 		   (tmp & MST_EOPB_DIS) ? " eopb-" : "",
1183 		   (tmp & MST_EOPB_ENA) ? " eopb+" : "",
1184 		   (tmp & MST_TIMEOUT_DIS) ? " tmo-" : "",
1185 		   (tmp & MST_TIMEOUT_ENA) ? " tmo+" : "",
1186 
1187 		   (tmp & MST_RD_EOPB) ? " eopb" : "",
1188 		   (tmp & MST_RD_RESET) ? " in_reset" : "",
1189 		   (tmp & MST_WR_RESET) ? " out_reset" : "",
1190 		   (tmp & MST_RD_ENA) ? " IN" : "",
1191 
1192 		   (tmp & MST_WR_ENA) ? " OUT" : "",
1193 		   (tmp & MST_CONNECTION) ? "ep1in/ep2out" : "ep1out/ep2in");
1194 	if (seq_has_overflowed(m))
1195 		goto done;
1196 
1197 	/* dump endpoint queues */
1198 	for (i = 0; i < 4; i++) {
1199 		struct goku_ep		*ep = &dev->ep [i];
1200 		struct goku_request	*req;
1201 
1202 		if (i && !ep->ep.desc)
1203 			continue;
1204 
1205 		tmp = readl(ep->reg_status);
1206 		seq_printf(m, "%s %s max %u %s, irqs %lu, status %02x (%s) " FOURBITS "\n",
1207 			   ep->ep.name,
1208 			   ep->is_in ? "in" : "out",
1209 			   ep->ep.maxpacket,
1210 			   ep->dma ? "dma" : "pio",
1211 			   ep->irqs,
1212 			   tmp, udc_ep_status(tmp),
1213 			   (tmp & EPxSTATUS_TOGGLE) ? "data1" : "data0",
1214 			   (tmp & EPxSTATUS_SUSPEND) ? " suspend" : "",
1215 			   (tmp & EPxSTATUS_FIFO_DISABLE) ? " disable" : "",
1216 			   (tmp & EPxSTATUS_STAGE_ERROR) ? " ep0stat" : "");
1217 		if (seq_has_overflowed(m))
1218 			goto done;
1219 
1220 		if (list_empty(&ep->queue)) {
1221 			seq_puts(m, "\t(nothing queued)\n");
1222 			if (seq_has_overflowed(m))
1223 				goto done;
1224 			continue;
1225 		}
1226 		list_for_each_entry(req, &ep->queue, queue) {
1227 			if (ep->dma && req->queue.prev == &ep->queue) {
1228 				if (i == UDC_MSTRD_ENDPOINT)
1229 					tmp = readl(&regs->in_dma_current);
1230 				else
1231 					tmp = readl(&regs->out_dma_current);
1232 				tmp -= req->req.dma;
1233 				tmp++;
1234 			} else
1235 				tmp = req->req.actual;
1236 
1237 			seq_printf(m, "\treq %p len %u/%u buf %p\n",
1238 				   &req->req, tmp, req->req.length,
1239 				   req->req.buf);
1240 			if (seq_has_overflowed(m))
1241 				goto done;
1242 		}
1243 	}
1244 
1245 done:
1246 	local_irq_restore(flags);
1247 	return 0;
1248 }
1249 #endif	/* CONFIG_USB_GADGET_DEBUG_FILES */
1250 
1251 /*-------------------------------------------------------------------------*/
1252 
1253 static void udc_reinit (struct goku_udc *dev)
1254 {
1255 	static char *names [] = { "ep0", "ep1-bulk", "ep2-bulk", "ep3-bulk" };
1256 
1257 	unsigned i;
1258 
1259 	INIT_LIST_HEAD (&dev->gadget.ep_list);
1260 	dev->gadget.ep0 = &dev->ep [0].ep;
1261 	dev->gadget.speed = USB_SPEED_UNKNOWN;
1262 	dev->ep0state = EP0_DISCONNECT;
1263 	dev->irqs = 0;
1264 
1265 	for (i = 0; i < 4; i++) {
1266 		struct goku_ep	*ep = &dev->ep[i];
1267 
1268 		ep->num = i;
1269 		ep->ep.name = names[i];
1270 		ep->reg_fifo = &dev->regs->ep_fifo [i];
1271 		ep->reg_status = &dev->regs->ep_status [i];
1272 		ep->reg_mode = &dev->regs->ep_mode[i];
1273 
1274 		ep->ep.ops = &goku_ep_ops;
1275 		list_add_tail (&ep->ep.ep_list, &dev->gadget.ep_list);
1276 		ep->dev = dev;
1277 		INIT_LIST_HEAD (&ep->queue);
1278 
1279 		ep_reset(NULL, ep);
1280 
1281 		if (i == 0)
1282 			ep->ep.caps.type_control = true;
1283 		else
1284 			ep->ep.caps.type_bulk = true;
1285 
1286 		ep->ep.caps.dir_in = true;
1287 		ep->ep.caps.dir_out = true;
1288 	}
1289 
1290 	dev->ep[0].reg_mode = NULL;
1291 	usb_ep_set_maxpacket_limit(&dev->ep[0].ep, MAX_EP0_SIZE);
1292 	list_del_init (&dev->ep[0].ep.ep_list);
1293 }
1294 
1295 static void udc_reset(struct goku_udc *dev)
1296 {
1297 	struct goku_udc_regs __iomem	*regs = dev->regs;
1298 
1299 	writel(0, &regs->power_detect);
1300 	writel(0, &regs->int_enable);
1301 	readl(&regs->int_enable);
1302 	dev->int_enable = 0;
1303 
1304 	/* deassert reset, leave USB D+ at hi-Z (no pullup)
1305 	 * don't let INT_PWRDETECT sequence begin
1306 	 */
1307 	udelay(250);
1308 	writel(PW_RESETB, &regs->power_detect);
1309 	readl(&regs->int_enable);
1310 }
1311 
1312 static void ep0_start(struct goku_udc *dev)
1313 {
1314 	struct goku_udc_regs __iomem	*regs = dev->regs;
1315 	unsigned			i;
1316 
1317 	VDBG(dev, "%s\n", __func__);
1318 
1319 	udc_reset(dev);
1320 	udc_reinit (dev);
1321 	//writel(MST_EOPB_ENA | MST_TIMEOUT_ENA, &regs->dma_master);
1322 
1323 	/* hw handles set_address, set_feature, get_status; maybe more */
1324 	writel(   G_REQMODE_SET_INTF | G_REQMODE_GET_INTF
1325 		| G_REQMODE_SET_CONF | G_REQMODE_GET_CONF
1326 		| G_REQMODE_GET_DESC
1327 		| G_REQMODE_CLEAR_FEAT
1328 		, &regs->reqmode);
1329 
1330 	for (i = 0; i < 4; i++)
1331 		dev->ep[i].irqs = 0;
1332 
1333 	/* can't modify descriptors after writing UsbReady */
1334 	for (i = 0; i < DESC_LEN; i++)
1335 		writel(0, &regs->descriptors[i]);
1336 	writel(0, &regs->UsbReady);
1337 
1338 	/* expect ep0 requests when the host drops reset */
1339 	writel(PW_RESETB | PW_PULLUP, &regs->power_detect);
1340 	dev->int_enable = INT_DEVWIDE | INT_EP0;
1341 	writel(dev->int_enable, &dev->regs->int_enable);
1342 	readl(&regs->int_enable);
1343 	dev->gadget.speed = USB_SPEED_FULL;
1344 	dev->ep0state = EP0_IDLE;
1345 }
1346 
1347 static void udc_enable(struct goku_udc *dev)
1348 {
1349 	/* start enumeration now, or after power detect irq */
1350 	if (readl(&dev->regs->power_detect) & PW_DETECT)
1351 		ep0_start(dev);
1352 	else {
1353 		DBG(dev, "%s\n", __func__);
1354 		dev->int_enable = INT_PWRDETECT;
1355 		writel(dev->int_enable, &dev->regs->int_enable);
1356 	}
1357 }
1358 
1359 /*-------------------------------------------------------------------------*/
1360 
1361 /* keeping it simple:
1362  * - one bus driver, initted first;
1363  * - one function driver, initted second
1364  */
1365 
1366 /* when a driver is successfully registered, it will receive
1367  * control requests including set_configuration(), which enables
1368  * non-control requests.  then usb traffic follows until a
1369  * disconnect is reported.  then a host may connect again, or
1370  * the driver might get unbound.
1371  */
1372 static int goku_udc_start(struct usb_gadget *g,
1373 		struct usb_gadget_driver *driver)
1374 {
1375 	struct goku_udc	*dev = to_goku_udc(g);
1376 
1377 	/* hook up the driver */
1378 	driver->driver.bus = NULL;
1379 	dev->driver = driver;
1380 
1381 	/*
1382 	 * then enable host detection and ep0; and we're ready
1383 	 * for set_configuration as well as eventual disconnect.
1384 	 */
1385 	udc_enable(dev);
1386 
1387 	return 0;
1388 }
1389 
1390 static void stop_activity(struct goku_udc *dev)
1391 {
1392 	unsigned	i;
1393 
1394 	DBG (dev, "%s\n", __func__);
1395 
1396 	/* disconnect gadget driver after quiesceing hw and the driver */
1397 	udc_reset (dev);
1398 	for (i = 0; i < 4; i++)
1399 		nuke(&dev->ep [i], -ESHUTDOWN);
1400 
1401 	if (dev->driver)
1402 		udc_enable(dev);
1403 }
1404 
1405 static int goku_udc_stop(struct usb_gadget *g)
1406 {
1407 	struct goku_udc	*dev = to_goku_udc(g);
1408 	unsigned long	flags;
1409 
1410 	spin_lock_irqsave(&dev->lock, flags);
1411 	dev->driver = NULL;
1412 	stop_activity(dev);
1413 	spin_unlock_irqrestore(&dev->lock, flags);
1414 
1415 	return 0;
1416 }
1417 
1418 /*-------------------------------------------------------------------------*/
1419 
1420 static void ep0_setup(struct goku_udc *dev)
1421 {
1422 	struct goku_udc_regs __iomem	*regs = dev->regs;
1423 	struct usb_ctrlrequest		ctrl;
1424 	int				tmp;
1425 
1426 	/* read SETUP packet and enter DATA stage */
1427 	ctrl.bRequestType = readl(&regs->bRequestType);
1428 	ctrl.bRequest = readl(&regs->bRequest);
1429 	ctrl.wValue  = cpu_to_le16((readl(&regs->wValueH)  << 8)
1430 					| readl(&regs->wValueL));
1431 	ctrl.wIndex  = cpu_to_le16((readl(&regs->wIndexH)  << 8)
1432 					| readl(&regs->wIndexL));
1433 	ctrl.wLength = cpu_to_le16((readl(&regs->wLengthH) << 8)
1434 					| readl(&regs->wLengthL));
1435 	writel(0, &regs->SetupRecv);
1436 
1437 	nuke(&dev->ep[0], 0);
1438 	dev->ep[0].stopped = 0;
1439 	if (likely(ctrl.bRequestType & USB_DIR_IN)) {
1440 		dev->ep[0].is_in = 1;
1441 		dev->ep0state = EP0_IN;
1442 		/* detect early status stages */
1443 		writel(ICONTROL_STATUSNAK, &dev->regs->IntControl);
1444 	} else {
1445 		dev->ep[0].is_in = 0;
1446 		dev->ep0state = EP0_OUT;
1447 
1448 		/* NOTE:  CLEAR_FEATURE is done in software so that we can
1449 		 * synchronize transfer restarts after bulk IN stalls.  data
1450 		 * won't even enter the fifo until the halt is cleared.
1451 		 */
1452 		switch (ctrl.bRequest) {
1453 		case USB_REQ_CLEAR_FEATURE:
1454 			switch (ctrl.bRequestType) {
1455 			case USB_RECIP_ENDPOINT:
1456 				tmp = le16_to_cpu(ctrl.wIndex) & 0x0f;
1457 				/* active endpoint */
1458 				if (tmp > 3 ||
1459 				    (!dev->ep[tmp].ep.desc && tmp != 0))
1460 					goto stall;
1461 				if (ctrl.wIndex & cpu_to_le16(
1462 						USB_DIR_IN)) {
1463 					if (!dev->ep[tmp].is_in)
1464 						goto stall;
1465 				} else {
1466 					if (dev->ep[tmp].is_in)
1467 						goto stall;
1468 				}
1469 				if (ctrl.wValue != cpu_to_le16(
1470 						USB_ENDPOINT_HALT))
1471 					goto stall;
1472 				if (tmp)
1473 					goku_clear_halt(&dev->ep[tmp]);
1474 succeed:
1475 				/* start ep0out status stage */
1476 				writel(~(1<<0), &regs->EOP);
1477 				dev->ep[0].stopped = 1;
1478 				dev->ep0state = EP0_STATUS;
1479 				return;
1480 			case USB_RECIP_DEVICE:
1481 				/* device remote wakeup: always clear */
1482 				if (ctrl.wValue != cpu_to_le16(1))
1483 					goto stall;
1484 				VDBG(dev, "clear dev remote wakeup\n");
1485 				goto succeed;
1486 			case USB_RECIP_INTERFACE:
1487 				goto stall;
1488 			default:		/* pass to gadget driver */
1489 				break;
1490 			}
1491 			break;
1492 		default:
1493 			break;
1494 		}
1495 	}
1496 
1497 #ifdef USB_TRACE
1498 	VDBG(dev, "SETUP %02x.%02x v%04x i%04x l%04x\n",
1499 		ctrl.bRequestType, ctrl.bRequest,
1500 		le16_to_cpu(ctrl.wValue), le16_to_cpu(ctrl.wIndex),
1501 		le16_to_cpu(ctrl.wLength));
1502 #endif
1503 
1504 	/* hw wants to know when we're configured (or not) */
1505 	dev->req_config = (ctrl.bRequest == USB_REQ_SET_CONFIGURATION
1506 				&& ctrl.bRequestType == USB_RECIP_DEVICE);
1507 	if (unlikely(dev->req_config))
1508 		dev->configured = (ctrl.wValue != cpu_to_le16(0));
1509 
1510 	/* delegate everything to the gadget driver.
1511 	 * it may respond after this irq handler returns.
1512 	 */
1513 	spin_unlock (&dev->lock);
1514 	tmp = dev->driver->setup(&dev->gadget, &ctrl);
1515 	spin_lock (&dev->lock);
1516 	if (unlikely(tmp < 0)) {
1517 stall:
1518 #ifdef USB_TRACE
1519 		VDBG(dev, "req %02x.%02x protocol STALL; err %d\n",
1520 				ctrl.bRequestType, ctrl.bRequest, tmp);
1521 #endif
1522 		command(regs, COMMAND_STALL, 0);
1523 		dev->ep[0].stopped = 1;
1524 		dev->ep0state = EP0_STALL;
1525 	}
1526 
1527 	/* expect at least one data or status stage irq */
1528 }
1529 
1530 #define ACK(irqbit) { \
1531 		stat &= ~irqbit; \
1532 		writel(~irqbit, &regs->int_status); \
1533 		handled = 1; \
1534 		}
1535 
1536 static irqreturn_t goku_irq(int irq, void *_dev)
1537 {
1538 	struct goku_udc			*dev = _dev;
1539 	struct goku_udc_regs __iomem	*regs = dev->regs;
1540 	struct goku_ep			*ep;
1541 	u32				stat, handled = 0;
1542 	unsigned			i, rescans = 5;
1543 
1544 	spin_lock(&dev->lock);
1545 
1546 rescan:
1547 	stat = readl(&regs->int_status) & dev->int_enable;
1548         if (!stat)
1549 		goto done;
1550 	dev->irqs++;
1551 
1552 	/* device-wide irqs */
1553 	if (unlikely(stat & INT_DEVWIDE)) {
1554 		if (stat & INT_SYSERROR) {
1555 			ERROR(dev, "system error\n");
1556 			stop_activity(dev);
1557 			stat = 0;
1558 			handled = 1;
1559 			// FIXME have a neater way to prevent re-enumeration
1560 			dev->driver = NULL;
1561 			goto done;
1562 		}
1563 		if (stat & INT_PWRDETECT) {
1564 			writel(~stat, &regs->int_status);
1565 			if (readl(&dev->regs->power_detect) & PW_DETECT) {
1566 				VDBG(dev, "connect\n");
1567 				ep0_start(dev);
1568 			} else {
1569 				DBG(dev, "disconnect\n");
1570 				if (dev->gadget.speed == USB_SPEED_FULL)
1571 					stop_activity(dev);
1572 				dev->ep0state = EP0_DISCONNECT;
1573 				dev->int_enable = INT_DEVWIDE;
1574 				writel(dev->int_enable, &dev->regs->int_enable);
1575 			}
1576 			stat = 0;
1577 			handled = 1;
1578 			goto done;
1579 		}
1580 		if (stat & INT_SUSPEND) {
1581 			ACK(INT_SUSPEND);
1582 			if (readl(&regs->ep_status[0]) & EPxSTATUS_SUSPEND) {
1583 				switch (dev->ep0state) {
1584 				case EP0_DISCONNECT:
1585 				case EP0_SUSPEND:
1586 					goto pm_next;
1587 				default:
1588 					break;
1589 				}
1590 				DBG(dev, "USB suspend\n");
1591 				dev->ep0state = EP0_SUSPEND;
1592 				if (dev->gadget.speed != USB_SPEED_UNKNOWN
1593 						&& dev->driver
1594 						&& dev->driver->suspend) {
1595 					spin_unlock(&dev->lock);
1596 					dev->driver->suspend(&dev->gadget);
1597 					spin_lock(&dev->lock);
1598 				}
1599 			} else {
1600 				if (dev->ep0state != EP0_SUSPEND) {
1601 					DBG(dev, "bogus USB resume %d\n",
1602 						dev->ep0state);
1603 					goto pm_next;
1604 				}
1605 				DBG(dev, "USB resume\n");
1606 				dev->ep0state = EP0_IDLE;
1607 				if (dev->gadget.speed != USB_SPEED_UNKNOWN
1608 						&& dev->driver
1609 						&& dev->driver->resume) {
1610 					spin_unlock(&dev->lock);
1611 					dev->driver->resume(&dev->gadget);
1612 					spin_lock(&dev->lock);
1613 				}
1614 			}
1615 		}
1616 pm_next:
1617 		if (stat & INT_USBRESET) {		/* hub reset done */
1618 			ACK(INT_USBRESET);
1619 			INFO(dev, "USB reset done, gadget %s\n",
1620 				dev->driver->driver.name);
1621 		}
1622 		// and INT_ERR on some endpoint's crc/bitstuff/... problem
1623 	}
1624 
1625 	/* progress ep0 setup, data, or status stages.
1626 	 * no transition {EP0_STATUS, EP0_STALL} --> EP0_IDLE; saves irqs
1627 	 */
1628 	if (stat & INT_SETUP) {
1629 		ACK(INT_SETUP);
1630 		dev->ep[0].irqs++;
1631 		ep0_setup(dev);
1632 	}
1633         if (stat & INT_STATUSNAK) {
1634 		ACK(INT_STATUSNAK|INT_ENDPOINT0);
1635 		if (dev->ep0state == EP0_IN) {
1636 			ep = &dev->ep[0];
1637 			ep->irqs++;
1638 			nuke(ep, 0);
1639 			writel(~(1<<0), &regs->EOP);
1640 			dev->ep0state = EP0_STATUS;
1641 		}
1642 	}
1643         if (stat & INT_ENDPOINT0) {
1644 		ACK(INT_ENDPOINT0);
1645 		ep = &dev->ep[0];
1646 		ep->irqs++;
1647 		pio_advance(ep);
1648         }
1649 
1650 	/* dma completion */
1651         if (stat & INT_MSTRDEND) {	/* IN */
1652 		ACK(INT_MSTRDEND);
1653 		ep = &dev->ep[UDC_MSTRD_ENDPOINT];
1654 		ep->irqs++;
1655 		dma_advance(dev, ep);
1656         }
1657         if (stat & INT_MSTWREND) {	/* OUT */
1658 		ACK(INT_MSTWREND);
1659 		ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1660 		ep->irqs++;
1661 		dma_advance(dev, ep);
1662         }
1663         if (stat & INT_MSTWRTMOUT) {	/* OUT */
1664 		ACK(INT_MSTWRTMOUT);
1665 		ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1666 		ep->irqs++;
1667 		ERROR(dev, "%s write timeout ?\n", ep->ep.name);
1668 		// reset dma? then dma_advance()
1669         }
1670 
1671 	/* pio */
1672 	for (i = 1; i < 4; i++) {
1673 		u32		tmp = INT_EPxDATASET(i);
1674 
1675 		if (!(stat & tmp))
1676 			continue;
1677 		ep = &dev->ep[i];
1678 		pio_advance(ep);
1679 		if (list_empty (&ep->queue))
1680 			pio_irq_disable(dev, regs, i);
1681 		stat &= ~tmp;
1682 		handled = 1;
1683 		ep->irqs++;
1684 	}
1685 
1686 	if (rescans--)
1687 		goto rescan;
1688 
1689 done:
1690 	(void)readl(&regs->int_enable);
1691 	spin_unlock(&dev->lock);
1692 	if (stat)
1693 		DBG(dev, "unhandled irq status: %05x (%05x, %05x)\n", stat,
1694 				readl(&regs->int_status), dev->int_enable);
1695 	return IRQ_RETVAL(handled);
1696 }
1697 
1698 #undef ACK
1699 
1700 /*-------------------------------------------------------------------------*/
1701 
1702 static void gadget_release(struct device *_dev)
1703 {
1704 	struct goku_udc	*dev = dev_get_drvdata(_dev);
1705 
1706 	kfree(dev);
1707 }
1708 
1709 /* tear down the binding between this driver and the pci device */
1710 
1711 static void goku_remove(struct pci_dev *pdev)
1712 {
1713 	struct goku_udc		*dev = pci_get_drvdata(pdev);
1714 
1715 	DBG(dev, "%s\n", __func__);
1716 
1717 	usb_del_gadget_udc(&dev->gadget);
1718 
1719 	BUG_ON(dev->driver);
1720 
1721 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1722 	remove_proc_entry(proc_node_name, NULL);
1723 #endif
1724 	if (dev->regs)
1725 		udc_reset(dev);
1726 	if (dev->got_irq)
1727 		free_irq(pdev->irq, dev);
1728 	if (dev->regs)
1729 		iounmap(dev->regs);
1730 	if (dev->got_region)
1731 		release_mem_region(pci_resource_start (pdev, 0),
1732 				pci_resource_len (pdev, 0));
1733 	if (dev->enabled)
1734 		pci_disable_device(pdev);
1735 
1736 	dev->regs = NULL;
1737 
1738 	INFO(dev, "unbind\n");
1739 }
1740 
1741 /* wrap this driver around the specified pci device, but
1742  * don't respond over USB until a gadget driver binds to us.
1743  */
1744 
1745 static int goku_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1746 {
1747 	struct goku_udc		*dev = NULL;
1748 	unsigned long		resource, len;
1749 	void __iomem		*base = NULL;
1750 	int			retval;
1751 
1752 	if (!pdev->irq) {
1753 		printk(KERN_ERR "Check PCI %s IRQ setup!\n", pci_name(pdev));
1754 		retval = -ENODEV;
1755 		goto err;
1756 	}
1757 
1758 	/* alloc, and start init */
1759 	dev = kzalloc (sizeof *dev, GFP_KERNEL);
1760 	if (!dev) {
1761 		retval = -ENOMEM;
1762 		goto err;
1763 	}
1764 
1765 	pci_set_drvdata(pdev, dev);
1766 	spin_lock_init(&dev->lock);
1767 	dev->pdev = pdev;
1768 	dev->gadget.ops = &goku_ops;
1769 	dev->gadget.max_speed = USB_SPEED_FULL;
1770 
1771 	/* the "gadget" abstracts/virtualizes the controller */
1772 	dev->gadget.name = driver_name;
1773 
1774 	/* now all the pci goodies ... */
1775 	retval = pci_enable_device(pdev);
1776 	if (retval < 0) {
1777 		DBG(dev, "can't enable, %d\n", retval);
1778 		goto err;
1779 	}
1780 	dev->enabled = 1;
1781 
1782 	resource = pci_resource_start(pdev, 0);
1783 	len = pci_resource_len(pdev, 0);
1784 	if (!request_mem_region(resource, len, driver_name)) {
1785 		DBG(dev, "controller already in use\n");
1786 		retval = -EBUSY;
1787 		goto err;
1788 	}
1789 	dev->got_region = 1;
1790 
1791 	base = ioremap(resource, len);
1792 	if (base == NULL) {
1793 		DBG(dev, "can't map memory\n");
1794 		retval = -EFAULT;
1795 		goto err;
1796 	}
1797 	dev->regs = (struct goku_udc_regs __iomem *) base;
1798 
1799 	INFO(dev, "%s\n", driver_desc);
1800 	INFO(dev, "version: " DRIVER_VERSION " %s\n", dmastr());
1801 	INFO(dev, "irq %d, pci mem %p\n", pdev->irq, base);
1802 
1803 	/* init to known state, then setup irqs */
1804 	udc_reset(dev);
1805 	udc_reinit (dev);
1806 	if (request_irq(pdev->irq, goku_irq, IRQF_SHARED,
1807 			driver_name, dev) != 0) {
1808 		DBG(dev, "request interrupt %d failed\n", pdev->irq);
1809 		retval = -EBUSY;
1810 		goto err;
1811 	}
1812 	dev->got_irq = 1;
1813 	if (use_dma)
1814 		pci_set_master(pdev);
1815 
1816 
1817 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1818 	proc_create_single_data(proc_node_name, 0, NULL, udc_proc_read, dev);
1819 #endif
1820 
1821 	retval = usb_add_gadget_udc_release(&pdev->dev, &dev->gadget,
1822 			gadget_release);
1823 	if (retval)
1824 		goto err;
1825 
1826 	return 0;
1827 
1828 err:
1829 	if (dev)
1830 		goku_remove (pdev);
1831 	/* gadget_release is not registered yet, kfree explicitly */
1832 	kfree(dev);
1833 	return retval;
1834 }
1835 
1836 
1837 /*-------------------------------------------------------------------------*/
1838 
1839 static const struct pci_device_id pci_ids[] = { {
1840 	.class =	PCI_CLASS_SERIAL_USB_DEVICE,
1841 	.class_mask =	~0,
1842 	.vendor =	0x102f,		/* Toshiba */
1843 	.device =	0x0107,		/* this UDC */
1844 	.subvendor =	PCI_ANY_ID,
1845 	.subdevice =	PCI_ANY_ID,
1846 
1847 }, { /* end: all zeroes */ }
1848 };
1849 MODULE_DEVICE_TABLE (pci, pci_ids);
1850 
1851 static struct pci_driver goku_pci_driver = {
1852 	.name =		driver_name,
1853 	.id_table =	pci_ids,
1854 
1855 	.probe =	goku_probe,
1856 	.remove =	goku_remove,
1857 
1858 	/* FIXME add power management support */
1859 };
1860 
1861 module_pci_driver(goku_pci_driver);
1862