xref: /openbmc/linux/drivers/usb/gadget/udc/goku_udc.c (revision 0da85d1e)
1 /*
2  * Toshiba TC86C001 ("Goku-S") USB Device Controller driver
3  *
4  * Copyright (C) 2000-2002 Lineo
5  *      by Stuart Lynne, Tom Rushworth, and Bruce Balden
6  * Copyright (C) 2002 Toshiba Corporation
7  * Copyright (C) 2003 MontaVista Software (source@mvista.com)
8  *
9  * This file is licensed under the terms of the GNU General Public
10  * License version 2.  This program is licensed "as is" without any
11  * warranty of any kind, whether express or implied.
12  */
13 
14 /*
15  * This device has ep0 and three semi-configurable bulk/interrupt endpoints.
16  *
17  *  - Endpoint numbering is fixed: ep{1,2,3}-bulk
18  *  - Gadget drivers can choose ep maxpacket (8/16/32/64)
19  *  - Gadget drivers can choose direction (IN, OUT)
20  *  - DMA works with ep1 (OUT transfers) and ep2 (IN transfers).
21  */
22 
23 // #define	VERBOSE		/* extra debug messages (success too) */
24 // #define	USB_TRACE	/* packet-level success messages */
25 
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/pci.h>
29 #include <linux/delay.h>
30 #include <linux/ioport.h>
31 #include <linux/slab.h>
32 #include <linux/errno.h>
33 #include <linux/timer.h>
34 #include <linux/list.h>
35 #include <linux/interrupt.h>
36 #include <linux/proc_fs.h>
37 #include <linux/seq_file.h>
38 #include <linux/device.h>
39 #include <linux/usb/ch9.h>
40 #include <linux/usb/gadget.h>
41 #include <linux/prefetch.h>
42 
43 #include <asm/byteorder.h>
44 #include <asm/io.h>
45 #include <asm/irq.h>
46 #include <asm/unaligned.h>
47 
48 
49 #include "goku_udc.h"
50 
51 #define	DRIVER_DESC		"TC86C001 USB Device Controller"
52 #define	DRIVER_VERSION		"30-Oct 2003"
53 
54 static const char driver_name [] = "goku_udc";
55 static const char driver_desc [] = DRIVER_DESC;
56 
57 MODULE_AUTHOR("source@mvista.com");
58 MODULE_DESCRIPTION(DRIVER_DESC);
59 MODULE_LICENSE("GPL");
60 
61 
62 /*
63  * IN dma behaves ok under testing, though the IN-dma abort paths don't
64  * seem to behave quite as expected.  Used by default.
65  *
66  * OUT dma documents design problems handling the common "short packet"
67  * transfer termination policy; it couldn't be enabled by default, even
68  * if the OUT-dma abort problems had a resolution.
69  */
70 static unsigned use_dma = 1;
71 
72 #if 0
73 //#include <linux/moduleparam.h>
74 /* "modprobe goku_udc use_dma=1" etc
75  *	0 to disable dma
76  *	1 to use IN dma only (normal operation)
77  *	2 to use IN and OUT dma
78  */
79 module_param(use_dma, uint, S_IRUGO);
80 #endif
81 
82 /*-------------------------------------------------------------------------*/
83 
84 static void nuke(struct goku_ep *, int status);
85 
86 static inline void
87 command(struct goku_udc_regs __iomem *regs, int command, unsigned epnum)
88 {
89 	writel(COMMAND_EP(epnum) | command, &regs->Command);
90 	udelay(300);
91 }
92 
93 static int
94 goku_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
95 {
96 	struct goku_udc	*dev;
97 	struct goku_ep	*ep;
98 	u32		mode;
99 	u16		max;
100 	unsigned long	flags;
101 
102 	ep = container_of(_ep, struct goku_ep, ep);
103 	if (!_ep || !desc
104 			|| desc->bDescriptorType != USB_DT_ENDPOINT)
105 		return -EINVAL;
106 	dev = ep->dev;
107 	if (ep == &dev->ep[0])
108 		return -EINVAL;
109 	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)
110 		return -ESHUTDOWN;
111 	if (ep->num != usb_endpoint_num(desc))
112 		return -EINVAL;
113 
114 	switch (usb_endpoint_type(desc)) {
115 	case USB_ENDPOINT_XFER_BULK:
116 	case USB_ENDPOINT_XFER_INT:
117 		break;
118 	default:
119 		return -EINVAL;
120 	}
121 
122 	if ((readl(ep->reg_status) & EPxSTATUS_EP_MASK)
123 			!= EPxSTATUS_EP_INVALID)
124 		return -EBUSY;
125 
126 	/* enabling the no-toggle interrupt mode would need an api hook */
127 	mode = 0;
128 	max = get_unaligned_le16(&desc->wMaxPacketSize);
129 	switch (max) {
130 	case 64:	mode++;
131 	case 32:	mode++;
132 	case 16:	mode++;
133 	case 8:		mode <<= 3;
134 			break;
135 	default:
136 		return -EINVAL;
137 	}
138 	mode |= 2 << 1;		/* bulk, or intr-with-toggle */
139 
140 	/* ep1/ep2 dma direction is chosen early; it works in the other
141 	 * direction, with pio.  be cautious with out-dma.
142 	 */
143 	ep->is_in = usb_endpoint_dir_in(desc);
144 	if (ep->is_in) {
145 		mode |= 1;
146 		ep->dma = (use_dma != 0) && (ep->num == UDC_MSTRD_ENDPOINT);
147 	} else {
148 		ep->dma = (use_dma == 2) && (ep->num == UDC_MSTWR_ENDPOINT);
149 		if (ep->dma)
150 			DBG(dev, "%s out-dma hides short packets\n",
151 				ep->ep.name);
152 	}
153 
154 	spin_lock_irqsave(&ep->dev->lock, flags);
155 
156 	/* ep1 and ep2 can do double buffering and/or dma */
157 	if (ep->num < 3) {
158 		struct goku_udc_regs __iomem	*regs = ep->dev->regs;
159 		u32				tmp;
160 
161 		/* double buffer except (for now) with pio in */
162 		tmp = ((ep->dma || !ep->is_in)
163 				? 0x10	/* double buffered */
164 				: 0x11	/* single buffer */
165 			) << ep->num;
166 		tmp |= readl(&regs->EPxSingle);
167 		writel(tmp, &regs->EPxSingle);
168 
169 		tmp = (ep->dma ? 0x10/*dma*/ : 0x11/*pio*/) << ep->num;
170 		tmp |= readl(&regs->EPxBCS);
171 		writel(tmp, &regs->EPxBCS);
172 	}
173 	writel(mode, ep->reg_mode);
174 	command(ep->dev->regs, COMMAND_RESET, ep->num);
175 	ep->ep.maxpacket = max;
176 	ep->stopped = 0;
177 	ep->ep.desc = desc;
178 	spin_unlock_irqrestore(&ep->dev->lock, flags);
179 
180 	DBG(dev, "enable %s %s %s maxpacket %u\n", ep->ep.name,
181 		ep->is_in ? "IN" : "OUT",
182 		ep->dma ? "dma" : "pio",
183 		max);
184 
185 	return 0;
186 }
187 
188 static void ep_reset(struct goku_udc_regs __iomem *regs, struct goku_ep *ep)
189 {
190 	struct goku_udc		*dev = ep->dev;
191 
192 	if (regs) {
193 		command(regs, COMMAND_INVALID, ep->num);
194 		if (ep->num) {
195 			if (ep->num == UDC_MSTWR_ENDPOINT)
196 				dev->int_enable &= ~(INT_MSTWREND
197 							|INT_MSTWRTMOUT);
198 			else if (ep->num == UDC_MSTRD_ENDPOINT)
199 				dev->int_enable &= ~INT_MSTRDEND;
200 			dev->int_enable &= ~INT_EPxDATASET (ep->num);
201 		} else
202 			dev->int_enable &= ~INT_EP0;
203 		writel(dev->int_enable, &regs->int_enable);
204 		readl(&regs->int_enable);
205 		if (ep->num < 3) {
206 			struct goku_udc_regs __iomem	*r = ep->dev->regs;
207 			u32				tmp;
208 
209 			tmp = readl(&r->EPxSingle);
210 			tmp &= ~(0x11 << ep->num);
211 			writel(tmp, &r->EPxSingle);
212 
213 			tmp = readl(&r->EPxBCS);
214 			tmp &= ~(0x11 << ep->num);
215 			writel(tmp, &r->EPxBCS);
216 		}
217 		/* reset dma in case we're still using it */
218 		if (ep->dma) {
219 			u32	master;
220 
221 			master = readl(&regs->dma_master) & MST_RW_BITS;
222 			if (ep->num == UDC_MSTWR_ENDPOINT) {
223 				master &= ~MST_W_BITS;
224 				master |= MST_WR_RESET;
225 			} else {
226 				master &= ~MST_R_BITS;
227 				master |= MST_RD_RESET;
228 			}
229 			writel(master, &regs->dma_master);
230 		}
231 	}
232 
233 	usb_ep_set_maxpacket_limit(&ep->ep, MAX_FIFO_SIZE);
234 	ep->ep.desc = NULL;
235 	ep->stopped = 1;
236 	ep->irqs = 0;
237 	ep->dma = 0;
238 }
239 
240 static int goku_ep_disable(struct usb_ep *_ep)
241 {
242 	struct goku_ep	*ep;
243 	struct goku_udc	*dev;
244 	unsigned long	flags;
245 
246 	ep = container_of(_ep, struct goku_ep, ep);
247 	if (!_ep || !ep->ep.desc)
248 		return -ENODEV;
249 	dev = ep->dev;
250 	if (dev->ep0state == EP0_SUSPEND)
251 		return -EBUSY;
252 
253 	VDBG(dev, "disable %s\n", _ep->name);
254 
255 	spin_lock_irqsave(&dev->lock, flags);
256 	nuke(ep, -ESHUTDOWN);
257 	ep_reset(dev->regs, ep);
258 	spin_unlock_irqrestore(&dev->lock, flags);
259 
260 	return 0;
261 }
262 
263 /*-------------------------------------------------------------------------*/
264 
265 static struct usb_request *
266 goku_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
267 {
268 	struct goku_request	*req;
269 
270 	if (!_ep)
271 		return NULL;
272 	req = kzalloc(sizeof *req, gfp_flags);
273 	if (!req)
274 		return NULL;
275 
276 	INIT_LIST_HEAD(&req->queue);
277 	return &req->req;
278 }
279 
280 static void
281 goku_free_request(struct usb_ep *_ep, struct usb_request *_req)
282 {
283 	struct goku_request	*req;
284 
285 	if (!_ep || !_req)
286 		return;
287 
288 	req = container_of(_req, struct goku_request, req);
289 	WARN_ON(!list_empty(&req->queue));
290 	kfree(req);
291 }
292 
293 /*-------------------------------------------------------------------------*/
294 
295 static void
296 done(struct goku_ep *ep, struct goku_request *req, int status)
297 {
298 	struct goku_udc		*dev;
299 	unsigned		stopped = ep->stopped;
300 
301 	list_del_init(&req->queue);
302 
303 	if (likely(req->req.status == -EINPROGRESS))
304 		req->req.status = status;
305 	else
306 		status = req->req.status;
307 
308 	dev = ep->dev;
309 
310 	if (ep->dma)
311 		usb_gadget_unmap_request(&dev->gadget, &req->req, ep->is_in);
312 
313 #ifndef USB_TRACE
314 	if (status && status != -ESHUTDOWN)
315 #endif
316 		VDBG(dev, "complete %s req %p stat %d len %u/%u\n",
317 			ep->ep.name, &req->req, status,
318 			req->req.actual, req->req.length);
319 
320 	/* don't modify queue heads during completion callback */
321 	ep->stopped = 1;
322 	spin_unlock(&dev->lock);
323 	usb_gadget_giveback_request(&ep->ep, &req->req);
324 	spin_lock(&dev->lock);
325 	ep->stopped = stopped;
326 }
327 
328 /*-------------------------------------------------------------------------*/
329 
330 static inline int
331 write_packet(u32 __iomem *fifo, u8 *buf, struct goku_request *req, unsigned max)
332 {
333 	unsigned	length, count;
334 
335 	length = min(req->req.length - req->req.actual, max);
336 	req->req.actual += length;
337 
338 	count = length;
339 	while (likely(count--))
340 		writel(*buf++, fifo);
341 	return length;
342 }
343 
344 // return:  0 = still running, 1 = completed, negative = errno
345 static int write_fifo(struct goku_ep *ep, struct goku_request *req)
346 {
347 	struct goku_udc	*dev = ep->dev;
348 	u32		tmp;
349 	u8		*buf;
350 	unsigned	count;
351 	int		is_last;
352 
353 	tmp = readl(&dev->regs->DataSet);
354 	buf = req->req.buf + req->req.actual;
355 	prefetch(buf);
356 
357 	dev = ep->dev;
358 	if (unlikely(ep->num == 0 && dev->ep0state != EP0_IN))
359 		return -EL2HLT;
360 
361 	/* NOTE:  just single-buffered PIO-IN for now.  */
362 	if (unlikely((tmp & DATASET_A(ep->num)) != 0))
363 		return 0;
364 
365 	/* clear our "packet available" irq */
366 	if (ep->num != 0)
367 		writel(~INT_EPxDATASET(ep->num), &dev->regs->int_status);
368 
369 	count = write_packet(ep->reg_fifo, buf, req, ep->ep.maxpacket);
370 
371 	/* last packet often short (sometimes a zlp, especially on ep0) */
372 	if (unlikely(count != ep->ep.maxpacket)) {
373 		writel(~(1<<ep->num), &dev->regs->EOP);
374 		if (ep->num == 0) {
375 			dev->ep[0].stopped = 1;
376 			dev->ep0state = EP0_STATUS;
377 		}
378 		is_last = 1;
379 	} else {
380 		if (likely(req->req.length != req->req.actual)
381 				|| req->req.zero)
382 			is_last = 0;
383 		else
384 			is_last = 1;
385 	}
386 #if 0		/* printk seemed to trash is_last...*/
387 //#ifdef USB_TRACE
388 	VDBG(dev, "wrote %s %u bytes%s IN %u left %p\n",
389 		ep->ep.name, count, is_last ? "/last" : "",
390 		req->req.length - req->req.actual, req);
391 #endif
392 
393 	/* requests complete when all IN data is in the FIFO,
394 	 * or sometimes later, if a zlp was needed.
395 	 */
396 	if (is_last) {
397 		done(ep, req, 0);
398 		return 1;
399 	}
400 
401 	return 0;
402 }
403 
404 static int read_fifo(struct goku_ep *ep, struct goku_request *req)
405 {
406 	struct goku_udc_regs __iomem	*regs;
407 	u32				size, set;
408 	u8				*buf;
409 	unsigned			bufferspace, is_short, dbuff;
410 
411 	regs = ep->dev->regs;
412 top:
413 	buf = req->req.buf + req->req.actual;
414 	prefetchw(buf);
415 
416 	if (unlikely(ep->num == 0 && ep->dev->ep0state != EP0_OUT))
417 		return -EL2HLT;
418 
419 	dbuff = (ep->num == 1 || ep->num == 2);
420 	do {
421 		/* ack dataset irq matching the status we'll handle */
422 		if (ep->num != 0)
423 			writel(~INT_EPxDATASET(ep->num), &regs->int_status);
424 
425 		set = readl(&regs->DataSet) & DATASET_AB(ep->num);
426 		size = readl(&regs->EPxSizeLA[ep->num]);
427 		bufferspace = req->req.length - req->req.actual;
428 
429 		/* usually do nothing without an OUT packet */
430 		if (likely(ep->num != 0 || bufferspace != 0)) {
431 			if (unlikely(set == 0))
432 				break;
433 			/* use ep1/ep2 double-buffering for OUT */
434 			if (!(size & PACKET_ACTIVE))
435 				size = readl(&regs->EPxSizeLB[ep->num]);
436 			if (!(size & PACKET_ACTIVE))	/* "can't happen" */
437 				break;
438 			size &= DATASIZE;	/* EPxSizeH == 0 */
439 
440 		/* ep0out no-out-data case for set_config, etc */
441 		} else
442 			size = 0;
443 
444 		/* read all bytes from this packet */
445 		req->req.actual += size;
446 		is_short = (size < ep->ep.maxpacket);
447 #ifdef USB_TRACE
448 		VDBG(ep->dev, "read %s %u bytes%s OUT req %p %u/%u\n",
449 			ep->ep.name, size, is_short ? "/S" : "",
450 			req, req->req.actual, req->req.length);
451 #endif
452 		while (likely(size-- != 0)) {
453 			u8	byte = (u8) readl(ep->reg_fifo);
454 
455 			if (unlikely(bufferspace == 0)) {
456 				/* this happens when the driver's buffer
457 				 * is smaller than what the host sent.
458 				 * discard the extra data in this packet.
459 				 */
460 				if (req->req.status != -EOVERFLOW)
461 					DBG(ep->dev, "%s overflow %u\n",
462 						ep->ep.name, size);
463 				req->req.status = -EOVERFLOW;
464 			} else {
465 				*buf++ = byte;
466 				bufferspace--;
467 			}
468 		}
469 
470 		/* completion */
471 		if (unlikely(is_short || req->req.actual == req->req.length)) {
472 			if (unlikely(ep->num == 0)) {
473 				/* non-control endpoints now usable? */
474 				if (ep->dev->req_config)
475 					writel(ep->dev->configured
476 							? USBSTATE_CONFIGURED
477 							: 0,
478 						&regs->UsbState);
479 				/* ep0out status stage */
480 				writel(~(1<<0), &regs->EOP);
481 				ep->stopped = 1;
482 				ep->dev->ep0state = EP0_STATUS;
483 			}
484 			done(ep, req, 0);
485 
486 			/* empty the second buffer asap */
487 			if (dbuff && !list_empty(&ep->queue)) {
488 				req = list_entry(ep->queue.next,
489 						struct goku_request, queue);
490 				goto top;
491 			}
492 			return 1;
493 		}
494 	} while (dbuff);
495 	return 0;
496 }
497 
498 static inline void
499 pio_irq_enable(struct goku_udc *dev,
500 		struct goku_udc_regs __iomem *regs, int epnum)
501 {
502 	dev->int_enable |= INT_EPxDATASET (epnum);
503 	writel(dev->int_enable, &regs->int_enable);
504 	/* write may still be posted */
505 }
506 
507 static inline void
508 pio_irq_disable(struct goku_udc *dev,
509 		struct goku_udc_regs __iomem *regs, int epnum)
510 {
511 	dev->int_enable &= ~INT_EPxDATASET (epnum);
512 	writel(dev->int_enable, &regs->int_enable);
513 	/* write may still be posted */
514 }
515 
516 static inline void
517 pio_advance(struct goku_ep *ep)
518 {
519 	struct goku_request	*req;
520 
521 	if (unlikely(list_empty (&ep->queue)))
522 		return;
523 	req = list_entry(ep->queue.next, struct goku_request, queue);
524 	(ep->is_in ? write_fifo : read_fifo)(ep, req);
525 }
526 
527 
528 /*-------------------------------------------------------------------------*/
529 
530 // return:  0 = q running, 1 = q stopped, negative = errno
531 static int start_dma(struct goku_ep *ep, struct goku_request *req)
532 {
533 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
534 	u32				master;
535 	u32				start = req->req.dma;
536 	u32				end = start + req->req.length - 1;
537 
538 	master = readl(&regs->dma_master) & MST_RW_BITS;
539 
540 	/* re-init the bits affecting IN dma; careful with zlps */
541 	if (likely(ep->is_in)) {
542 		if (unlikely(master & MST_RD_ENA)) {
543 			DBG (ep->dev, "start, IN active dma %03x!!\n",
544 				master);
545 //			return -EL2HLT;
546 		}
547 		writel(end, &regs->in_dma_end);
548 		writel(start, &regs->in_dma_start);
549 
550 		master &= ~MST_R_BITS;
551 		if (unlikely(req->req.length == 0))
552 			master = MST_RD_ENA | MST_RD_EOPB;
553 		else if ((req->req.length % ep->ep.maxpacket) != 0
554 					|| req->req.zero)
555 			master = MST_RD_ENA | MST_EOPB_ENA;
556 		else
557 			master = MST_RD_ENA | MST_EOPB_DIS;
558 
559 		ep->dev->int_enable |= INT_MSTRDEND;
560 
561 	/* Goku DMA-OUT merges short packets, which plays poorly with
562 	 * protocols where short packets mark the transfer boundaries.
563 	 * The chip supports a nonstandard policy with INT_MSTWRTMOUT,
564 	 * ending transfers after 3 SOFs; we don't turn it on.
565 	 */
566 	} else {
567 		if (unlikely(master & MST_WR_ENA)) {
568 			DBG (ep->dev, "start, OUT active dma %03x!!\n",
569 				master);
570 //			return -EL2HLT;
571 		}
572 		writel(end, &regs->out_dma_end);
573 		writel(start, &regs->out_dma_start);
574 
575 		master &= ~MST_W_BITS;
576 		master |= MST_WR_ENA | MST_TIMEOUT_DIS;
577 
578 		ep->dev->int_enable |= INT_MSTWREND|INT_MSTWRTMOUT;
579 	}
580 
581 	writel(master, &regs->dma_master);
582 	writel(ep->dev->int_enable, &regs->int_enable);
583 	return 0;
584 }
585 
586 static void dma_advance(struct goku_udc *dev, struct goku_ep *ep)
587 {
588 	struct goku_request		*req;
589 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
590 	u32				master;
591 
592 	master = readl(&regs->dma_master);
593 
594 	if (unlikely(list_empty(&ep->queue))) {
595 stop:
596 		if (ep->is_in)
597 			dev->int_enable &= ~INT_MSTRDEND;
598 		else
599 			dev->int_enable &= ~(INT_MSTWREND|INT_MSTWRTMOUT);
600 		writel(dev->int_enable, &regs->int_enable);
601 		return;
602 	}
603 	req = list_entry(ep->queue.next, struct goku_request, queue);
604 
605 	/* normal hw dma completion (not abort) */
606 	if (likely(ep->is_in)) {
607 		if (unlikely(master & MST_RD_ENA))
608 			return;
609 		req->req.actual = readl(&regs->in_dma_current);
610 	} else {
611 		if (unlikely(master & MST_WR_ENA))
612 			return;
613 
614 		/* hardware merges short packets, and also hides packet
615 		 * overruns.  a partial packet MAY be in the fifo here.
616 		 */
617 		req->req.actual = readl(&regs->out_dma_current);
618 	}
619 	req->req.actual -= req->req.dma;
620 	req->req.actual++;
621 
622 #ifdef USB_TRACE
623 	VDBG(dev, "done %s %s dma, %u/%u bytes, req %p\n",
624 		ep->ep.name, ep->is_in ? "IN" : "OUT",
625 		req->req.actual, req->req.length, req);
626 #endif
627 	done(ep, req, 0);
628 	if (list_empty(&ep->queue))
629 		goto stop;
630 	req = list_entry(ep->queue.next, struct goku_request, queue);
631 	(void) start_dma(ep, req);
632 }
633 
634 static void abort_dma(struct goku_ep *ep, int status)
635 {
636 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
637 	struct goku_request		*req;
638 	u32				curr, master;
639 
640 	/* NAK future host requests, hoping the implicit delay lets the
641 	 * dma engine finish reading (or writing) its latest packet and
642 	 * empty the dma buffer (up to 16 bytes).
643 	 *
644 	 * This avoids needing to clean up a partial packet in the fifo;
645 	 * we can't do that for IN without side effects to HALT and TOGGLE.
646 	 */
647 	command(regs, COMMAND_FIFO_DISABLE, ep->num);
648 	req = list_entry(ep->queue.next, struct goku_request, queue);
649 	master = readl(&regs->dma_master) & MST_RW_BITS;
650 
651 	/* FIXME using these resets isn't usably documented. this may
652 	 * not work unless it's followed by disabling the endpoint.
653 	 *
654 	 * FIXME the OUT reset path doesn't even behave consistently.
655 	 */
656 	if (ep->is_in) {
657 		if (unlikely((readl(&regs->dma_master) & MST_RD_ENA) == 0))
658 			goto finished;
659 		curr = readl(&regs->in_dma_current);
660 
661 		writel(curr, &regs->in_dma_end);
662 		writel(curr, &regs->in_dma_start);
663 
664 		master &= ~MST_R_BITS;
665 		master |= MST_RD_RESET;
666 		writel(master, &regs->dma_master);
667 
668 		if (readl(&regs->dma_master) & MST_RD_ENA)
669 			DBG(ep->dev, "IN dma active after reset!\n");
670 
671 	} else {
672 		if (unlikely((readl(&regs->dma_master) & MST_WR_ENA) == 0))
673 			goto finished;
674 		curr = readl(&regs->out_dma_current);
675 
676 		writel(curr, &regs->out_dma_end);
677 		writel(curr, &regs->out_dma_start);
678 
679 		master &= ~MST_W_BITS;
680 		master |= MST_WR_RESET;
681 		writel(master, &regs->dma_master);
682 
683 		if (readl(&regs->dma_master) & MST_WR_ENA)
684 			DBG(ep->dev, "OUT dma active after reset!\n");
685 	}
686 	req->req.actual = (curr - req->req.dma) + 1;
687 	req->req.status = status;
688 
689 	VDBG(ep->dev, "%s %s %s %d/%d\n", __func__, ep->ep.name,
690 		ep->is_in ? "IN" : "OUT",
691 		req->req.actual, req->req.length);
692 
693 	command(regs, COMMAND_FIFO_ENABLE, ep->num);
694 
695 	return;
696 
697 finished:
698 	/* dma already completed; no abort needed */
699 	command(regs, COMMAND_FIFO_ENABLE, ep->num);
700 	req->req.actual = req->req.length;
701 	req->req.status = 0;
702 }
703 
704 /*-------------------------------------------------------------------------*/
705 
706 static int
707 goku_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags)
708 {
709 	struct goku_request	*req;
710 	struct goku_ep		*ep;
711 	struct goku_udc		*dev;
712 	unsigned long		flags;
713 	int			status;
714 
715 	/* always require a cpu-view buffer so pio works */
716 	req = container_of(_req, struct goku_request, req);
717 	if (unlikely(!_req || !_req->complete
718 			|| !_req->buf || !list_empty(&req->queue)))
719 		return -EINVAL;
720 	ep = container_of(_ep, struct goku_ep, ep);
721 	if (unlikely(!_ep || (!ep->ep.desc && ep->num != 0)))
722 		return -EINVAL;
723 	dev = ep->dev;
724 	if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN))
725 		return -ESHUTDOWN;
726 
727 	/* can't touch registers when suspended */
728 	if (dev->ep0state == EP0_SUSPEND)
729 		return -EBUSY;
730 
731 	/* set up dma mapping in case the caller didn't */
732 	if (ep->dma) {
733 		status = usb_gadget_map_request(&dev->gadget, &req->req,
734 				ep->is_in);
735 		if (status)
736 			return status;
737 	}
738 
739 #ifdef USB_TRACE
740 	VDBG(dev, "%s queue req %p, len %u buf %p\n",
741 			_ep->name, _req, _req->length, _req->buf);
742 #endif
743 
744 	spin_lock_irqsave(&dev->lock, flags);
745 
746 	_req->status = -EINPROGRESS;
747 	_req->actual = 0;
748 
749 	/* for ep0 IN without premature status, zlp is required and
750 	 * writing EOP starts the status stage (OUT).
751 	 */
752 	if (unlikely(ep->num == 0 && ep->is_in))
753 		_req->zero = 1;
754 
755 	/* kickstart this i/o queue? */
756 	status = 0;
757 	if (list_empty(&ep->queue) && likely(!ep->stopped)) {
758 		/* dma:  done after dma completion IRQ (or error)
759 		 * pio:  done after last fifo operation
760 		 */
761 		if (ep->dma)
762 			status = start_dma(ep, req);
763 		else
764 			status = (ep->is_in ? write_fifo : read_fifo)(ep, req);
765 
766 		if (unlikely(status != 0)) {
767 			if (status > 0)
768 				status = 0;
769 			req = NULL;
770 		}
771 
772 	} /* else pio or dma irq handler advances the queue. */
773 
774 	if (likely(req != NULL))
775 		list_add_tail(&req->queue, &ep->queue);
776 
777 	if (likely(!list_empty(&ep->queue))
778 			&& likely(ep->num != 0)
779 			&& !ep->dma
780 			&& !(dev->int_enable & INT_EPxDATASET (ep->num)))
781 		pio_irq_enable(dev, dev->regs, ep->num);
782 
783 	spin_unlock_irqrestore(&dev->lock, flags);
784 
785 	/* pci writes may still be posted */
786 	return status;
787 }
788 
789 /* dequeue ALL requests */
790 static void nuke(struct goku_ep *ep, int status)
791 {
792 	struct goku_request	*req;
793 
794 	ep->stopped = 1;
795 	if (list_empty(&ep->queue))
796 		return;
797 	if (ep->dma)
798 		abort_dma(ep, status);
799 	while (!list_empty(&ep->queue)) {
800 		req = list_entry(ep->queue.next, struct goku_request, queue);
801 		done(ep, req, status);
802 	}
803 }
804 
805 /* dequeue JUST ONE request */
806 static int goku_dequeue(struct usb_ep *_ep, struct usb_request *_req)
807 {
808 	struct goku_request	*req;
809 	struct goku_ep		*ep;
810 	struct goku_udc		*dev;
811 	unsigned long		flags;
812 
813 	ep = container_of(_ep, struct goku_ep, ep);
814 	if (!_ep || !_req || (!ep->ep.desc && ep->num != 0))
815 		return -EINVAL;
816 	dev = ep->dev;
817 	if (!dev->driver)
818 		return -ESHUTDOWN;
819 
820 	/* we can't touch (dma) registers when suspended */
821 	if (dev->ep0state == EP0_SUSPEND)
822 		return -EBUSY;
823 
824 	VDBG(dev, "%s %s %s %s %p\n", __func__, _ep->name,
825 		ep->is_in ? "IN" : "OUT",
826 		ep->dma ? "dma" : "pio",
827 		_req);
828 
829 	spin_lock_irqsave(&dev->lock, flags);
830 
831 	/* make sure it's actually queued on this endpoint */
832 	list_for_each_entry (req, &ep->queue, queue) {
833 		if (&req->req == _req)
834 			break;
835 	}
836 	if (&req->req != _req) {
837 		spin_unlock_irqrestore (&dev->lock, flags);
838 		return -EINVAL;
839 	}
840 
841 	if (ep->dma && ep->queue.next == &req->queue && !ep->stopped) {
842 		abort_dma(ep, -ECONNRESET);
843 		done(ep, req, -ECONNRESET);
844 		dma_advance(dev, ep);
845 	} else if (!list_empty(&req->queue))
846 		done(ep, req, -ECONNRESET);
847 	else
848 		req = NULL;
849 	spin_unlock_irqrestore(&dev->lock, flags);
850 
851 	return req ? 0 : -EOPNOTSUPP;
852 }
853 
854 /*-------------------------------------------------------------------------*/
855 
856 static void goku_clear_halt(struct goku_ep *ep)
857 {
858 	// assert (ep->num !=0)
859 	VDBG(ep->dev, "%s clear halt\n", ep->ep.name);
860 	command(ep->dev->regs, COMMAND_SETDATA0, ep->num);
861 	command(ep->dev->regs, COMMAND_STALL_CLEAR, ep->num);
862 	if (ep->stopped) {
863 		ep->stopped = 0;
864 		if (ep->dma) {
865 			struct goku_request	*req;
866 
867 			if (list_empty(&ep->queue))
868 				return;
869 			req = list_entry(ep->queue.next, struct goku_request,
870 						queue);
871 			(void) start_dma(ep, req);
872 		} else
873 			pio_advance(ep);
874 	}
875 }
876 
877 static int goku_set_halt(struct usb_ep *_ep, int value)
878 {
879 	struct goku_ep	*ep;
880 	unsigned long	flags;
881 	int		retval = 0;
882 
883 	if (!_ep)
884 		return -ENODEV;
885 	ep = container_of (_ep, struct goku_ep, ep);
886 
887 	if (ep->num == 0) {
888 		if (value) {
889 			ep->dev->ep0state = EP0_STALL;
890 			ep->dev->ep[0].stopped = 1;
891 		} else
892 			return -EINVAL;
893 
894 	/* don't change EPxSTATUS_EP_INVALID to READY */
895 	} else if (!ep->ep.desc) {
896 		DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
897 		return -EINVAL;
898 	}
899 
900 	spin_lock_irqsave(&ep->dev->lock, flags);
901 	if (!list_empty(&ep->queue))
902 		retval = -EAGAIN;
903 	else if (ep->is_in && value
904 			/* data in (either) packet buffer? */
905 			&& (readl(&ep->dev->regs->DataSet)
906 					& DATASET_AB(ep->num)))
907 		retval = -EAGAIN;
908 	else if (!value)
909 		goku_clear_halt(ep);
910 	else {
911 		ep->stopped = 1;
912 		VDBG(ep->dev, "%s set halt\n", ep->ep.name);
913 		command(ep->dev->regs, COMMAND_STALL, ep->num);
914 		readl(ep->reg_status);
915 	}
916 	spin_unlock_irqrestore(&ep->dev->lock, flags);
917 	return retval;
918 }
919 
920 static int goku_fifo_status(struct usb_ep *_ep)
921 {
922 	struct goku_ep			*ep;
923 	struct goku_udc_regs __iomem	*regs;
924 	u32				size;
925 
926 	if (!_ep)
927 		return -ENODEV;
928 	ep = container_of(_ep, struct goku_ep, ep);
929 
930 	/* size is only reported sanely for OUT */
931 	if (ep->is_in)
932 		return -EOPNOTSUPP;
933 
934 	/* ignores 16-byte dma buffer; SizeH == 0 */
935 	regs = ep->dev->regs;
936 	size = readl(&regs->EPxSizeLA[ep->num]) & DATASIZE;
937 	size += readl(&regs->EPxSizeLB[ep->num]) & DATASIZE;
938 	VDBG(ep->dev, "%s %s %u\n", __func__, ep->ep.name, size);
939 	return size;
940 }
941 
942 static void goku_fifo_flush(struct usb_ep *_ep)
943 {
944 	struct goku_ep			*ep;
945 	struct goku_udc_regs __iomem	*regs;
946 	u32				size;
947 
948 	if (!_ep)
949 		return;
950 	ep = container_of(_ep, struct goku_ep, ep);
951 	VDBG(ep->dev, "%s %s\n", __func__, ep->ep.name);
952 
953 	/* don't change EPxSTATUS_EP_INVALID to READY */
954 	if (!ep->ep.desc && ep->num != 0) {
955 		DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
956 		return;
957 	}
958 
959 	regs = ep->dev->regs;
960 	size = readl(&regs->EPxSizeLA[ep->num]);
961 	size &= DATASIZE;
962 
963 	/* Non-desirable behavior:  FIFO_CLEAR also clears the
964 	 * endpoint halt feature.  For OUT, we _could_ just read
965 	 * the bytes out (PIO, if !ep->dma); for in, no choice.
966 	 */
967 	if (size)
968 		command(regs, COMMAND_FIFO_CLEAR, ep->num);
969 }
970 
971 static struct usb_ep_ops goku_ep_ops = {
972 	.enable		= goku_ep_enable,
973 	.disable	= goku_ep_disable,
974 
975 	.alloc_request	= goku_alloc_request,
976 	.free_request	= goku_free_request,
977 
978 	.queue		= goku_queue,
979 	.dequeue	= goku_dequeue,
980 
981 	.set_halt	= goku_set_halt,
982 	.fifo_status	= goku_fifo_status,
983 	.fifo_flush	= goku_fifo_flush,
984 };
985 
986 /*-------------------------------------------------------------------------*/
987 
988 static int goku_get_frame(struct usb_gadget *_gadget)
989 {
990 	return -EOPNOTSUPP;
991 }
992 
993 static int goku_udc_start(struct usb_gadget *g,
994 		struct usb_gadget_driver *driver);
995 static int goku_udc_stop(struct usb_gadget *g);
996 
997 static const struct usb_gadget_ops goku_ops = {
998 	.get_frame	= goku_get_frame,
999 	.udc_start	= goku_udc_start,
1000 	.udc_stop	= goku_udc_stop,
1001 	// no remote wakeup
1002 	// not selfpowered
1003 };
1004 
1005 /*-------------------------------------------------------------------------*/
1006 
1007 static inline const char *dmastr(void)
1008 {
1009 	if (use_dma == 0)
1010 		return "(dma disabled)";
1011 	else if (use_dma == 2)
1012 		return "(dma IN and OUT)";
1013 	else
1014 		return "(dma IN)";
1015 }
1016 
1017 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1018 
1019 static const char proc_node_name [] = "driver/udc";
1020 
1021 #define FOURBITS "%s%s%s%s"
1022 #define EIGHTBITS FOURBITS FOURBITS
1023 
1024 static void dump_intmask(struct seq_file *m, const char *label, u32 mask)
1025 {
1026 	/* int_status is the same format ... */
1027 	seq_printf(m, "%s %05X =" FOURBITS EIGHTBITS EIGHTBITS "\n",
1028 		   label, mask,
1029 		   (mask & INT_PWRDETECT) ? " power" : "",
1030 		   (mask & INT_SYSERROR) ? " sys" : "",
1031 		   (mask & INT_MSTRDEND) ? " in-dma" : "",
1032 		   (mask & INT_MSTWRTMOUT) ? " wrtmo" : "",
1033 
1034 		   (mask & INT_MSTWREND) ? " out-dma" : "",
1035 		   (mask & INT_MSTWRSET) ? " wrset" : "",
1036 		   (mask & INT_ERR) ? " err" : "",
1037 		   (mask & INT_SOF) ? " sof" : "",
1038 
1039 		   (mask & INT_EP3NAK) ? " ep3nak" : "",
1040 		   (mask & INT_EP2NAK) ? " ep2nak" : "",
1041 		   (mask & INT_EP1NAK) ? " ep1nak" : "",
1042 		   (mask & INT_EP3DATASET) ? " ep3" : "",
1043 
1044 		   (mask & INT_EP2DATASET) ? " ep2" : "",
1045 		   (mask & INT_EP1DATASET) ? " ep1" : "",
1046 		   (mask & INT_STATUSNAK) ? " ep0snak" : "",
1047 		   (mask & INT_STATUS) ? " ep0status" : "",
1048 
1049 		   (mask & INT_SETUP) ? " setup" : "",
1050 		   (mask & INT_ENDPOINT0) ? " ep0" : "",
1051 		   (mask & INT_USBRESET) ? " reset" : "",
1052 		   (mask & INT_SUSPEND) ? " suspend" : "");
1053 }
1054 
1055 static const char *udc_ep_state(enum ep0state state)
1056 {
1057 	switch (state) {
1058 	case EP0_DISCONNECT:
1059 		return "ep0_disconnect";
1060 	case EP0_IDLE:
1061 		return "ep0_idle";
1062 	case EP0_IN:
1063 		return "ep0_in";
1064 	case EP0_OUT:
1065 		return "ep0_out";
1066 	case EP0_STATUS:
1067 		return "ep0_status";
1068 	case EP0_STALL:
1069 		return "ep0_stall";
1070 	case EP0_SUSPEND:
1071 		return "ep0_suspend";
1072 	}
1073 
1074 	return "ep0_?";
1075 }
1076 
1077 static const char *udc_ep_status(u32 status)
1078 {
1079 	switch (status & EPxSTATUS_EP_MASK) {
1080 	case EPxSTATUS_EP_READY:
1081 		return "ready";
1082 	case EPxSTATUS_EP_DATAIN:
1083 		return "packet";
1084 	case EPxSTATUS_EP_FULL:
1085 		return "full";
1086 	case EPxSTATUS_EP_TX_ERR:	/* host will retry */
1087 		return "tx_err";
1088 	case EPxSTATUS_EP_RX_ERR:
1089 		return "rx_err";
1090 	case EPxSTATUS_EP_BUSY:		/* ep0 only */
1091 		return "busy";
1092 	case EPxSTATUS_EP_STALL:
1093 		return "stall";
1094 	case EPxSTATUS_EP_INVALID:	/* these "can't happen" */
1095 		return "invalid";
1096 	}
1097 
1098 	return "?";
1099 }
1100 
1101 static int udc_proc_read(struct seq_file *m, void *v)
1102 {
1103 	struct goku_udc			*dev = m->private;
1104 	struct goku_udc_regs __iomem	*regs = dev->regs;
1105 	unsigned long			flags;
1106 	int				i, is_usb_connected;
1107 	u32				tmp;
1108 
1109 	local_irq_save(flags);
1110 
1111 	/* basic device status */
1112 	tmp = readl(&regs->power_detect);
1113 	is_usb_connected = tmp & PW_DETECT;
1114 	seq_printf(m,
1115 		   "%s - %s\n"
1116 		   "%s version: %s %s\n"
1117 		   "Gadget driver: %s\n"
1118 		   "Host %s, %s\n"
1119 		   "\n",
1120 		   pci_name(dev->pdev), driver_desc,
1121 		   driver_name, DRIVER_VERSION, dmastr(),
1122 		   dev->driver ? dev->driver->driver.name : "(none)",
1123 		   is_usb_connected
1124 			   ? ((tmp & PW_PULLUP) ? "full speed" : "powered")
1125 			   : "disconnected",
1126 		   udc_ep_state(dev->ep0state));
1127 
1128 	dump_intmask(m, "int_status", readl(&regs->int_status));
1129 	dump_intmask(m, "int_enable", readl(&regs->int_enable));
1130 
1131 	if (!is_usb_connected || !dev->driver || (tmp & PW_PULLUP) == 0)
1132 		goto done;
1133 
1134 	/* registers for (active) device and ep0 */
1135 	seq_printf(m, "\nirqs %lu\ndataset %02x single.bcs %02x.%02x state %x addr %u\n",
1136 		   dev->irqs, readl(&regs->DataSet),
1137 		   readl(&regs->EPxSingle), readl(&regs->EPxBCS),
1138 		   readl(&regs->UsbState),
1139 		   readl(&regs->address));
1140 	if (seq_has_overflowed(m))
1141 		goto done;
1142 
1143 	tmp = readl(&regs->dma_master);
1144 	seq_printf(m, "dma %03X =" EIGHTBITS "%s %s\n",
1145 		   tmp,
1146 		   (tmp & MST_EOPB_DIS) ? " eopb-" : "",
1147 		   (tmp & MST_EOPB_ENA) ? " eopb+" : "",
1148 		   (tmp & MST_TIMEOUT_DIS) ? " tmo-" : "",
1149 		   (tmp & MST_TIMEOUT_ENA) ? " tmo+" : "",
1150 
1151 		   (tmp & MST_RD_EOPB) ? " eopb" : "",
1152 		   (tmp & MST_RD_RESET) ? " in_reset" : "",
1153 		   (tmp & MST_WR_RESET) ? " out_reset" : "",
1154 		   (tmp & MST_RD_ENA) ? " IN" : "",
1155 
1156 		   (tmp & MST_WR_ENA) ? " OUT" : "",
1157 		   (tmp & MST_CONNECTION) ? "ep1in/ep2out" : "ep1out/ep2in");
1158 	if (seq_has_overflowed(m))
1159 		goto done;
1160 
1161 	/* dump endpoint queues */
1162 	for (i = 0; i < 4; i++) {
1163 		struct goku_ep		*ep = &dev->ep [i];
1164 		struct goku_request	*req;
1165 
1166 		if (i && !ep->ep.desc)
1167 			continue;
1168 
1169 		tmp = readl(ep->reg_status);
1170 		seq_printf(m, "%s %s max %u %s, irqs %lu, status %02x (%s) " FOURBITS "\n",
1171 			   ep->ep.name,
1172 			   ep->is_in ? "in" : "out",
1173 			   ep->ep.maxpacket,
1174 			   ep->dma ? "dma" : "pio",
1175 			   ep->irqs,
1176 			   tmp, udc_ep_status(tmp),
1177 			   (tmp & EPxSTATUS_TOGGLE) ? "data1" : "data0",
1178 			   (tmp & EPxSTATUS_SUSPEND) ? " suspend" : "",
1179 			   (tmp & EPxSTATUS_FIFO_DISABLE) ? " disable" : "",
1180 			   (tmp & EPxSTATUS_STAGE_ERROR) ? " ep0stat" : "");
1181 		if (seq_has_overflowed(m))
1182 			goto done;
1183 
1184 		if (list_empty(&ep->queue)) {
1185 			seq_puts(m, "\t(nothing queued)\n");
1186 			if (seq_has_overflowed(m))
1187 				goto done;
1188 			continue;
1189 		}
1190 		list_for_each_entry(req, &ep->queue, queue) {
1191 			if (ep->dma && req->queue.prev == &ep->queue) {
1192 				if (i == UDC_MSTRD_ENDPOINT)
1193 					tmp = readl(&regs->in_dma_current);
1194 				else
1195 					tmp = readl(&regs->out_dma_current);
1196 				tmp -= req->req.dma;
1197 				tmp++;
1198 			} else
1199 				tmp = req->req.actual;
1200 
1201 			seq_printf(m, "\treq %p len %u/%u buf %p\n",
1202 				   &req->req, tmp, req->req.length,
1203 				   req->req.buf);
1204 			if (seq_has_overflowed(m))
1205 				goto done;
1206 		}
1207 	}
1208 
1209 done:
1210 	local_irq_restore(flags);
1211 	return 0;
1212 }
1213 
1214 /*
1215  * seq_file wrappers for procfile show routines.
1216  */
1217 static int udc_proc_open(struct inode *inode, struct file *file)
1218 {
1219 	return single_open(file, udc_proc_read, PDE_DATA(file_inode(file)));
1220 }
1221 
1222 static const struct file_operations udc_proc_fops = {
1223 	.open		= udc_proc_open,
1224 	.read		= seq_read,
1225 	.llseek		= seq_lseek,
1226 	.release	= single_release,
1227 };
1228 
1229 #endif	/* CONFIG_USB_GADGET_DEBUG_FILES */
1230 
1231 /*-------------------------------------------------------------------------*/
1232 
1233 static void udc_reinit (struct goku_udc *dev)
1234 {
1235 	static char *names [] = { "ep0", "ep1-bulk", "ep2-bulk", "ep3-bulk" };
1236 
1237 	unsigned i;
1238 
1239 	INIT_LIST_HEAD (&dev->gadget.ep_list);
1240 	dev->gadget.ep0 = &dev->ep [0].ep;
1241 	dev->gadget.speed = USB_SPEED_UNKNOWN;
1242 	dev->ep0state = EP0_DISCONNECT;
1243 	dev->irqs = 0;
1244 
1245 	for (i = 0; i < 4; i++) {
1246 		struct goku_ep	*ep = &dev->ep[i];
1247 
1248 		ep->num = i;
1249 		ep->ep.name = names[i];
1250 		ep->reg_fifo = &dev->regs->ep_fifo [i];
1251 		ep->reg_status = &dev->regs->ep_status [i];
1252 		ep->reg_mode = &dev->regs->ep_mode[i];
1253 
1254 		ep->ep.ops = &goku_ep_ops;
1255 		list_add_tail (&ep->ep.ep_list, &dev->gadget.ep_list);
1256 		ep->dev = dev;
1257 		INIT_LIST_HEAD (&ep->queue);
1258 
1259 		ep_reset(NULL, ep);
1260 	}
1261 
1262 	dev->ep[0].reg_mode = NULL;
1263 	usb_ep_set_maxpacket_limit(&dev->ep[0].ep, MAX_EP0_SIZE);
1264 	list_del_init (&dev->ep[0].ep.ep_list);
1265 }
1266 
1267 static void udc_reset(struct goku_udc *dev)
1268 {
1269 	struct goku_udc_regs __iomem	*regs = dev->regs;
1270 
1271 	writel(0, &regs->power_detect);
1272 	writel(0, &regs->int_enable);
1273 	readl(&regs->int_enable);
1274 	dev->int_enable = 0;
1275 
1276 	/* deassert reset, leave USB D+ at hi-Z (no pullup)
1277 	 * don't let INT_PWRDETECT sequence begin
1278 	 */
1279 	udelay(250);
1280 	writel(PW_RESETB, &regs->power_detect);
1281 	readl(&regs->int_enable);
1282 }
1283 
1284 static void ep0_start(struct goku_udc *dev)
1285 {
1286 	struct goku_udc_regs __iomem	*regs = dev->regs;
1287 	unsigned			i;
1288 
1289 	VDBG(dev, "%s\n", __func__);
1290 
1291 	udc_reset(dev);
1292 	udc_reinit (dev);
1293 	//writel(MST_EOPB_ENA | MST_TIMEOUT_ENA, &regs->dma_master);
1294 
1295 	/* hw handles set_address, set_feature, get_status; maybe more */
1296 	writel(   G_REQMODE_SET_INTF | G_REQMODE_GET_INTF
1297 		| G_REQMODE_SET_CONF | G_REQMODE_GET_CONF
1298 		| G_REQMODE_GET_DESC
1299 		| G_REQMODE_CLEAR_FEAT
1300 		, &regs->reqmode);
1301 
1302 	for (i = 0; i < 4; i++)
1303 		dev->ep[i].irqs = 0;
1304 
1305 	/* can't modify descriptors after writing UsbReady */
1306 	for (i = 0; i < DESC_LEN; i++)
1307 		writel(0, &regs->descriptors[i]);
1308 	writel(0, &regs->UsbReady);
1309 
1310 	/* expect ep0 requests when the host drops reset */
1311 	writel(PW_RESETB | PW_PULLUP, &regs->power_detect);
1312 	dev->int_enable = INT_DEVWIDE | INT_EP0;
1313 	writel(dev->int_enable, &dev->regs->int_enable);
1314 	readl(&regs->int_enable);
1315 	dev->gadget.speed = USB_SPEED_FULL;
1316 	dev->ep0state = EP0_IDLE;
1317 }
1318 
1319 static void udc_enable(struct goku_udc *dev)
1320 {
1321 	/* start enumeration now, or after power detect irq */
1322 	if (readl(&dev->regs->power_detect) & PW_DETECT)
1323 		ep0_start(dev);
1324 	else {
1325 		DBG(dev, "%s\n", __func__);
1326 		dev->int_enable = INT_PWRDETECT;
1327 		writel(dev->int_enable, &dev->regs->int_enable);
1328 	}
1329 }
1330 
1331 /*-------------------------------------------------------------------------*/
1332 
1333 /* keeping it simple:
1334  * - one bus driver, initted first;
1335  * - one function driver, initted second
1336  */
1337 
1338 /* when a driver is successfully registered, it will receive
1339  * control requests including set_configuration(), which enables
1340  * non-control requests.  then usb traffic follows until a
1341  * disconnect is reported.  then a host may connect again, or
1342  * the driver might get unbound.
1343  */
1344 static int goku_udc_start(struct usb_gadget *g,
1345 		struct usb_gadget_driver *driver)
1346 {
1347 	struct goku_udc	*dev = to_goku_udc(g);
1348 
1349 	/* hook up the driver */
1350 	driver->driver.bus = NULL;
1351 	dev->driver = driver;
1352 
1353 	/*
1354 	 * then enable host detection and ep0; and we're ready
1355 	 * for set_configuration as well as eventual disconnect.
1356 	 */
1357 	udc_enable(dev);
1358 
1359 	return 0;
1360 }
1361 
1362 static void stop_activity(struct goku_udc *dev)
1363 {
1364 	unsigned	i;
1365 
1366 	DBG (dev, "%s\n", __func__);
1367 
1368 	/* disconnect gadget driver after quiesceing hw and the driver */
1369 	udc_reset (dev);
1370 	for (i = 0; i < 4; i++)
1371 		nuke(&dev->ep [i], -ESHUTDOWN);
1372 
1373 	if (dev->driver)
1374 		udc_enable(dev);
1375 }
1376 
1377 static int goku_udc_stop(struct usb_gadget *g)
1378 {
1379 	struct goku_udc	*dev = to_goku_udc(g);
1380 	unsigned long	flags;
1381 
1382 	spin_lock_irqsave(&dev->lock, flags);
1383 	dev->driver = NULL;
1384 	stop_activity(dev);
1385 	spin_unlock_irqrestore(&dev->lock, flags);
1386 
1387 	return 0;
1388 }
1389 
1390 /*-------------------------------------------------------------------------*/
1391 
1392 static void ep0_setup(struct goku_udc *dev)
1393 {
1394 	struct goku_udc_regs __iomem	*regs = dev->regs;
1395 	struct usb_ctrlrequest		ctrl;
1396 	int				tmp;
1397 
1398 	/* read SETUP packet and enter DATA stage */
1399 	ctrl.bRequestType = readl(&regs->bRequestType);
1400 	ctrl.bRequest = readl(&regs->bRequest);
1401 	ctrl.wValue  = cpu_to_le16((readl(&regs->wValueH)  << 8)
1402 					| readl(&regs->wValueL));
1403 	ctrl.wIndex  = cpu_to_le16((readl(&regs->wIndexH)  << 8)
1404 					| readl(&regs->wIndexL));
1405 	ctrl.wLength = cpu_to_le16((readl(&regs->wLengthH) << 8)
1406 					| readl(&regs->wLengthL));
1407 	writel(0, &regs->SetupRecv);
1408 
1409 	nuke(&dev->ep[0], 0);
1410 	dev->ep[0].stopped = 0;
1411 	if (likely(ctrl.bRequestType & USB_DIR_IN)) {
1412 		dev->ep[0].is_in = 1;
1413 		dev->ep0state = EP0_IN;
1414 		/* detect early status stages */
1415 		writel(ICONTROL_STATUSNAK, &dev->regs->IntControl);
1416 	} else {
1417 		dev->ep[0].is_in = 0;
1418 		dev->ep0state = EP0_OUT;
1419 
1420 		/* NOTE:  CLEAR_FEATURE is done in software so that we can
1421 		 * synchronize transfer restarts after bulk IN stalls.  data
1422 		 * won't even enter the fifo until the halt is cleared.
1423 		 */
1424 		switch (ctrl.bRequest) {
1425 		case USB_REQ_CLEAR_FEATURE:
1426 			switch (ctrl.bRequestType) {
1427 			case USB_RECIP_ENDPOINT:
1428 				tmp = le16_to_cpu(ctrl.wIndex) & 0x0f;
1429 				/* active endpoint */
1430 				if (tmp > 3 ||
1431 				    (!dev->ep[tmp].ep.desc && tmp != 0))
1432 					goto stall;
1433 				if (ctrl.wIndex & cpu_to_le16(
1434 						USB_DIR_IN)) {
1435 					if (!dev->ep[tmp].is_in)
1436 						goto stall;
1437 				} else {
1438 					if (dev->ep[tmp].is_in)
1439 						goto stall;
1440 				}
1441 				if (ctrl.wValue != cpu_to_le16(
1442 						USB_ENDPOINT_HALT))
1443 					goto stall;
1444 				if (tmp)
1445 					goku_clear_halt(&dev->ep[tmp]);
1446 succeed:
1447 				/* start ep0out status stage */
1448 				writel(~(1<<0), &regs->EOP);
1449 				dev->ep[0].stopped = 1;
1450 				dev->ep0state = EP0_STATUS;
1451 				return;
1452 			case USB_RECIP_DEVICE:
1453 				/* device remote wakeup: always clear */
1454 				if (ctrl.wValue != cpu_to_le16(1))
1455 					goto stall;
1456 				VDBG(dev, "clear dev remote wakeup\n");
1457 				goto succeed;
1458 			case USB_RECIP_INTERFACE:
1459 				goto stall;
1460 			default:		/* pass to gadget driver */
1461 				break;
1462 			}
1463 			break;
1464 		default:
1465 			break;
1466 		}
1467 	}
1468 
1469 #ifdef USB_TRACE
1470 	VDBG(dev, "SETUP %02x.%02x v%04x i%04x l%04x\n",
1471 		ctrl.bRequestType, ctrl.bRequest,
1472 		le16_to_cpu(ctrl.wValue), le16_to_cpu(ctrl.wIndex),
1473 		le16_to_cpu(ctrl.wLength));
1474 #endif
1475 
1476 	/* hw wants to know when we're configured (or not) */
1477 	dev->req_config = (ctrl.bRequest == USB_REQ_SET_CONFIGURATION
1478 				&& ctrl.bRequestType == USB_RECIP_DEVICE);
1479 	if (unlikely(dev->req_config))
1480 		dev->configured = (ctrl.wValue != cpu_to_le16(0));
1481 
1482 	/* delegate everything to the gadget driver.
1483 	 * it may respond after this irq handler returns.
1484 	 */
1485 	spin_unlock (&dev->lock);
1486 	tmp = dev->driver->setup(&dev->gadget, &ctrl);
1487 	spin_lock (&dev->lock);
1488 	if (unlikely(tmp < 0)) {
1489 stall:
1490 #ifdef USB_TRACE
1491 		VDBG(dev, "req %02x.%02x protocol STALL; err %d\n",
1492 				ctrl.bRequestType, ctrl.bRequest, tmp);
1493 #endif
1494 		command(regs, COMMAND_STALL, 0);
1495 		dev->ep[0].stopped = 1;
1496 		dev->ep0state = EP0_STALL;
1497 	}
1498 
1499 	/* expect at least one data or status stage irq */
1500 }
1501 
1502 #define ACK(irqbit) { \
1503 		stat &= ~irqbit; \
1504 		writel(~irqbit, &regs->int_status); \
1505 		handled = 1; \
1506 		}
1507 
1508 static irqreturn_t goku_irq(int irq, void *_dev)
1509 {
1510 	struct goku_udc			*dev = _dev;
1511 	struct goku_udc_regs __iomem	*regs = dev->regs;
1512 	struct goku_ep			*ep;
1513 	u32				stat, handled = 0;
1514 	unsigned			i, rescans = 5;
1515 
1516 	spin_lock(&dev->lock);
1517 
1518 rescan:
1519 	stat = readl(&regs->int_status) & dev->int_enable;
1520         if (!stat)
1521 		goto done;
1522 	dev->irqs++;
1523 
1524 	/* device-wide irqs */
1525 	if (unlikely(stat & INT_DEVWIDE)) {
1526 		if (stat & INT_SYSERROR) {
1527 			ERROR(dev, "system error\n");
1528 			stop_activity(dev);
1529 			stat = 0;
1530 			handled = 1;
1531 			// FIXME have a neater way to prevent re-enumeration
1532 			dev->driver = NULL;
1533 			goto done;
1534 		}
1535 		if (stat & INT_PWRDETECT) {
1536 			writel(~stat, &regs->int_status);
1537 			if (readl(&dev->regs->power_detect) & PW_DETECT) {
1538 				VDBG(dev, "connect\n");
1539 				ep0_start(dev);
1540 			} else {
1541 				DBG(dev, "disconnect\n");
1542 				if (dev->gadget.speed == USB_SPEED_FULL)
1543 					stop_activity(dev);
1544 				dev->ep0state = EP0_DISCONNECT;
1545 				dev->int_enable = INT_DEVWIDE;
1546 				writel(dev->int_enable, &dev->regs->int_enable);
1547 			}
1548 			stat = 0;
1549 			handled = 1;
1550 			goto done;
1551 		}
1552 		if (stat & INT_SUSPEND) {
1553 			ACK(INT_SUSPEND);
1554 			if (readl(&regs->ep_status[0]) & EPxSTATUS_SUSPEND) {
1555 				switch (dev->ep0state) {
1556 				case EP0_DISCONNECT:
1557 				case EP0_SUSPEND:
1558 					goto pm_next;
1559 				default:
1560 					break;
1561 				}
1562 				DBG(dev, "USB suspend\n");
1563 				dev->ep0state = EP0_SUSPEND;
1564 				if (dev->gadget.speed != USB_SPEED_UNKNOWN
1565 						&& dev->driver
1566 						&& dev->driver->suspend) {
1567 					spin_unlock(&dev->lock);
1568 					dev->driver->suspend(&dev->gadget);
1569 					spin_lock(&dev->lock);
1570 				}
1571 			} else {
1572 				if (dev->ep0state != EP0_SUSPEND) {
1573 					DBG(dev, "bogus USB resume %d\n",
1574 						dev->ep0state);
1575 					goto pm_next;
1576 				}
1577 				DBG(dev, "USB resume\n");
1578 				dev->ep0state = EP0_IDLE;
1579 				if (dev->gadget.speed != USB_SPEED_UNKNOWN
1580 						&& dev->driver
1581 						&& dev->driver->resume) {
1582 					spin_unlock(&dev->lock);
1583 					dev->driver->resume(&dev->gadget);
1584 					spin_lock(&dev->lock);
1585 				}
1586 			}
1587 		}
1588 pm_next:
1589 		if (stat & INT_USBRESET) {		/* hub reset done */
1590 			ACK(INT_USBRESET);
1591 			INFO(dev, "USB reset done, gadget %s\n",
1592 				dev->driver->driver.name);
1593 		}
1594 		// and INT_ERR on some endpoint's crc/bitstuff/... problem
1595 	}
1596 
1597 	/* progress ep0 setup, data, or status stages.
1598 	 * no transition {EP0_STATUS, EP0_STALL} --> EP0_IDLE; saves irqs
1599 	 */
1600 	if (stat & INT_SETUP) {
1601 		ACK(INT_SETUP);
1602 		dev->ep[0].irqs++;
1603 		ep0_setup(dev);
1604 	}
1605         if (stat & INT_STATUSNAK) {
1606 		ACK(INT_STATUSNAK|INT_ENDPOINT0);
1607 		if (dev->ep0state == EP0_IN) {
1608 			ep = &dev->ep[0];
1609 			ep->irqs++;
1610 			nuke(ep, 0);
1611 			writel(~(1<<0), &regs->EOP);
1612 			dev->ep0state = EP0_STATUS;
1613 		}
1614 	}
1615         if (stat & INT_ENDPOINT0) {
1616 		ACK(INT_ENDPOINT0);
1617 		ep = &dev->ep[0];
1618 		ep->irqs++;
1619 		pio_advance(ep);
1620         }
1621 
1622 	/* dma completion */
1623         if (stat & INT_MSTRDEND) {	/* IN */
1624 		ACK(INT_MSTRDEND);
1625 		ep = &dev->ep[UDC_MSTRD_ENDPOINT];
1626 		ep->irqs++;
1627 		dma_advance(dev, ep);
1628         }
1629         if (stat & INT_MSTWREND) {	/* OUT */
1630 		ACK(INT_MSTWREND);
1631 		ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1632 		ep->irqs++;
1633 		dma_advance(dev, ep);
1634         }
1635         if (stat & INT_MSTWRTMOUT) {	/* OUT */
1636 		ACK(INT_MSTWRTMOUT);
1637 		ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1638 		ep->irqs++;
1639 		ERROR(dev, "%s write timeout ?\n", ep->ep.name);
1640 		// reset dma? then dma_advance()
1641         }
1642 
1643 	/* pio */
1644 	for (i = 1; i < 4; i++) {
1645 		u32		tmp = INT_EPxDATASET(i);
1646 
1647 		if (!(stat & tmp))
1648 			continue;
1649 		ep = &dev->ep[i];
1650 		pio_advance(ep);
1651 		if (list_empty (&ep->queue))
1652 			pio_irq_disable(dev, regs, i);
1653 		stat &= ~tmp;
1654 		handled = 1;
1655 		ep->irqs++;
1656 	}
1657 
1658 	if (rescans--)
1659 		goto rescan;
1660 
1661 done:
1662 	(void)readl(&regs->int_enable);
1663 	spin_unlock(&dev->lock);
1664 	if (stat)
1665 		DBG(dev, "unhandled irq status: %05x (%05x, %05x)\n", stat,
1666 				readl(&regs->int_status), dev->int_enable);
1667 	return IRQ_RETVAL(handled);
1668 }
1669 
1670 #undef ACK
1671 
1672 /*-------------------------------------------------------------------------*/
1673 
1674 static void gadget_release(struct device *_dev)
1675 {
1676 	struct goku_udc	*dev = dev_get_drvdata(_dev);
1677 
1678 	kfree(dev);
1679 }
1680 
1681 /* tear down the binding between this driver and the pci device */
1682 
1683 static void goku_remove(struct pci_dev *pdev)
1684 {
1685 	struct goku_udc		*dev = pci_get_drvdata(pdev);
1686 
1687 	DBG(dev, "%s\n", __func__);
1688 
1689 	usb_del_gadget_udc(&dev->gadget);
1690 
1691 	BUG_ON(dev->driver);
1692 
1693 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1694 	remove_proc_entry(proc_node_name, NULL);
1695 #endif
1696 	if (dev->regs)
1697 		udc_reset(dev);
1698 	if (dev->got_irq)
1699 		free_irq(pdev->irq, dev);
1700 	if (dev->regs)
1701 		iounmap(dev->regs);
1702 	if (dev->got_region)
1703 		release_mem_region(pci_resource_start (pdev, 0),
1704 				pci_resource_len (pdev, 0));
1705 	if (dev->enabled)
1706 		pci_disable_device(pdev);
1707 
1708 	dev->regs = NULL;
1709 
1710 	INFO(dev, "unbind\n");
1711 }
1712 
1713 /* wrap this driver around the specified pci device, but
1714  * don't respond over USB until a gadget driver binds to us.
1715  */
1716 
1717 static int goku_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1718 {
1719 	struct goku_udc		*dev = NULL;
1720 	unsigned long		resource, len;
1721 	void __iomem		*base = NULL;
1722 	int			retval;
1723 
1724 	if (!pdev->irq) {
1725 		printk(KERN_ERR "Check PCI %s IRQ setup!\n", pci_name(pdev));
1726 		retval = -ENODEV;
1727 		goto err;
1728 	}
1729 
1730 	/* alloc, and start init */
1731 	dev = kzalloc (sizeof *dev, GFP_KERNEL);
1732 	if (dev == NULL){
1733 		pr_debug("enomem %s\n", pci_name(pdev));
1734 		retval = -ENOMEM;
1735 		goto err;
1736 	}
1737 
1738 	spin_lock_init(&dev->lock);
1739 	dev->pdev = pdev;
1740 	dev->gadget.ops = &goku_ops;
1741 	dev->gadget.max_speed = USB_SPEED_FULL;
1742 
1743 	/* the "gadget" abstracts/virtualizes the controller */
1744 	dev->gadget.name = driver_name;
1745 
1746 	/* now all the pci goodies ... */
1747 	retval = pci_enable_device(pdev);
1748 	if (retval < 0) {
1749 		DBG(dev, "can't enable, %d\n", retval);
1750 		goto err;
1751 	}
1752 	dev->enabled = 1;
1753 
1754 	resource = pci_resource_start(pdev, 0);
1755 	len = pci_resource_len(pdev, 0);
1756 	if (!request_mem_region(resource, len, driver_name)) {
1757 		DBG(dev, "controller already in use\n");
1758 		retval = -EBUSY;
1759 		goto err;
1760 	}
1761 	dev->got_region = 1;
1762 
1763 	base = ioremap_nocache(resource, len);
1764 	if (base == NULL) {
1765 		DBG(dev, "can't map memory\n");
1766 		retval = -EFAULT;
1767 		goto err;
1768 	}
1769 	dev->regs = (struct goku_udc_regs __iomem *) base;
1770 
1771 	pci_set_drvdata(pdev, dev);
1772 	INFO(dev, "%s\n", driver_desc);
1773 	INFO(dev, "version: " DRIVER_VERSION " %s\n", dmastr());
1774 	INFO(dev, "irq %d, pci mem %p\n", pdev->irq, base);
1775 
1776 	/* init to known state, then setup irqs */
1777 	udc_reset(dev);
1778 	udc_reinit (dev);
1779 	if (request_irq(pdev->irq, goku_irq, IRQF_SHARED,
1780 			driver_name, dev) != 0) {
1781 		DBG(dev, "request interrupt %d failed\n", pdev->irq);
1782 		retval = -EBUSY;
1783 		goto err;
1784 	}
1785 	dev->got_irq = 1;
1786 	if (use_dma)
1787 		pci_set_master(pdev);
1788 
1789 
1790 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1791 	proc_create_data(proc_node_name, 0, NULL, &udc_proc_fops, dev);
1792 #endif
1793 
1794 	retval = usb_add_gadget_udc_release(&pdev->dev, &dev->gadget,
1795 			gadget_release);
1796 	if (retval)
1797 		goto err;
1798 
1799 	return 0;
1800 
1801 err:
1802 	if (dev)
1803 		goku_remove (pdev);
1804 	return retval;
1805 }
1806 
1807 
1808 /*-------------------------------------------------------------------------*/
1809 
1810 static const struct pci_device_id pci_ids[] = { {
1811 	.class =	((PCI_CLASS_SERIAL_USB << 8) | 0xfe),
1812 	.class_mask =	~0,
1813 	.vendor =	0x102f,		/* Toshiba */
1814 	.device =	0x0107,		/* this UDC */
1815 	.subvendor =	PCI_ANY_ID,
1816 	.subdevice =	PCI_ANY_ID,
1817 
1818 }, { /* end: all zeroes */ }
1819 };
1820 MODULE_DEVICE_TABLE (pci, pci_ids);
1821 
1822 static struct pci_driver goku_pci_driver = {
1823 	.name =		(char *) driver_name,
1824 	.id_table =	pci_ids,
1825 
1826 	.probe =	goku_probe,
1827 	.remove =	goku_remove,
1828 
1829 	/* FIXME add power management support */
1830 };
1831 
1832 module_pci_driver(goku_pci_driver);
1833