xref: /openbmc/linux/drivers/usb/gadget/udc/goku_udc.c (revision 15e3ae36)
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++; /* fall through */
129 	case 32:
130 		mode++; /* fall through */
131 	case 16:
132 		mode++; /* fall through */
133 	case 8:
134 		mode <<= 3;
135 		break;
136 	default:
137 		return -EINVAL;
138 	}
139 	mode |= 2 << 1;		/* bulk, or intr-with-toggle */
140 
141 	/* ep1/ep2 dma direction is chosen early; it works in the other
142 	 * direction, with pio.  be cautious with out-dma.
143 	 */
144 	ep->is_in = usb_endpoint_dir_in(desc);
145 	if (ep->is_in) {
146 		mode |= 1;
147 		ep->dma = (use_dma != 0) && (ep->num == UDC_MSTRD_ENDPOINT);
148 	} else {
149 		ep->dma = (use_dma == 2) && (ep->num == UDC_MSTWR_ENDPOINT);
150 		if (ep->dma)
151 			DBG(dev, "%s out-dma hides short packets\n",
152 				ep->ep.name);
153 	}
154 
155 	spin_lock_irqsave(&ep->dev->lock, flags);
156 
157 	/* ep1 and ep2 can do double buffering and/or dma */
158 	if (ep->num < 3) {
159 		struct goku_udc_regs __iomem	*regs = ep->dev->regs;
160 		u32				tmp;
161 
162 		/* double buffer except (for now) with pio in */
163 		tmp = ((ep->dma || !ep->is_in)
164 				? 0x10	/* double buffered */
165 				: 0x11	/* single buffer */
166 			) << ep->num;
167 		tmp |= readl(&regs->EPxSingle);
168 		writel(tmp, &regs->EPxSingle);
169 
170 		tmp = (ep->dma ? 0x10/*dma*/ : 0x11/*pio*/) << ep->num;
171 		tmp |= readl(&regs->EPxBCS);
172 		writel(tmp, &regs->EPxBCS);
173 	}
174 	writel(mode, ep->reg_mode);
175 	command(ep->dev->regs, COMMAND_RESET, ep->num);
176 	ep->ep.maxpacket = max;
177 	ep->stopped = 0;
178 	ep->ep.desc = desc;
179 	spin_unlock_irqrestore(&ep->dev->lock, flags);
180 
181 	DBG(dev, "enable %s %s %s maxpacket %u\n", ep->ep.name,
182 		ep->is_in ? "IN" : "OUT",
183 		ep->dma ? "dma" : "pio",
184 		max);
185 
186 	return 0;
187 }
188 
189 static void ep_reset(struct goku_udc_regs __iomem *regs, struct goku_ep *ep)
190 {
191 	struct goku_udc		*dev = ep->dev;
192 
193 	if (regs) {
194 		command(regs, COMMAND_INVALID, ep->num);
195 		if (ep->num) {
196 			if (ep->num == UDC_MSTWR_ENDPOINT)
197 				dev->int_enable &= ~(INT_MSTWREND
198 							|INT_MSTWRTMOUT);
199 			else if (ep->num == UDC_MSTRD_ENDPOINT)
200 				dev->int_enable &= ~INT_MSTRDEND;
201 			dev->int_enable &= ~INT_EPxDATASET (ep->num);
202 		} else
203 			dev->int_enable &= ~INT_EP0;
204 		writel(dev->int_enable, &regs->int_enable);
205 		readl(&regs->int_enable);
206 		if (ep->num < 3) {
207 			struct goku_udc_regs __iomem	*r = ep->dev->regs;
208 			u32				tmp;
209 
210 			tmp = readl(&r->EPxSingle);
211 			tmp &= ~(0x11 << ep->num);
212 			writel(tmp, &r->EPxSingle);
213 
214 			tmp = readl(&r->EPxBCS);
215 			tmp &= ~(0x11 << ep->num);
216 			writel(tmp, &r->EPxBCS);
217 		}
218 		/* reset dma in case we're still using it */
219 		if (ep->dma) {
220 			u32	master;
221 
222 			master = readl(&regs->dma_master) & MST_RW_BITS;
223 			if (ep->num == UDC_MSTWR_ENDPOINT) {
224 				master &= ~MST_W_BITS;
225 				master |= MST_WR_RESET;
226 			} else {
227 				master &= ~MST_R_BITS;
228 				master |= MST_RD_RESET;
229 			}
230 			writel(master, &regs->dma_master);
231 		}
232 	}
233 
234 	usb_ep_set_maxpacket_limit(&ep->ep, MAX_FIFO_SIZE);
235 	ep->ep.desc = NULL;
236 	ep->stopped = 1;
237 	ep->irqs = 0;
238 	ep->dma = 0;
239 }
240 
241 static int goku_ep_disable(struct usb_ep *_ep)
242 {
243 	struct goku_ep	*ep;
244 	struct goku_udc	*dev;
245 	unsigned long	flags;
246 
247 	ep = container_of(_ep, struct goku_ep, ep);
248 	if (!_ep || !ep->ep.desc)
249 		return -ENODEV;
250 	dev = ep->dev;
251 	if (dev->ep0state == EP0_SUSPEND)
252 		return -EBUSY;
253 
254 	VDBG(dev, "disable %s\n", _ep->name);
255 
256 	spin_lock_irqsave(&dev->lock, flags);
257 	nuke(ep, -ESHUTDOWN);
258 	ep_reset(dev->regs, ep);
259 	spin_unlock_irqrestore(&dev->lock, flags);
260 
261 	return 0;
262 }
263 
264 /*-------------------------------------------------------------------------*/
265 
266 static struct usb_request *
267 goku_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
268 {
269 	struct goku_request	*req;
270 
271 	if (!_ep)
272 		return NULL;
273 	req = kzalloc(sizeof *req, gfp_flags);
274 	if (!req)
275 		return NULL;
276 
277 	INIT_LIST_HEAD(&req->queue);
278 	return &req->req;
279 }
280 
281 static void
282 goku_free_request(struct usb_ep *_ep, struct usb_request *_req)
283 {
284 	struct goku_request	*req;
285 
286 	if (!_ep || !_req)
287 		return;
288 
289 	req = container_of(_req, struct goku_request, req);
290 	WARN_ON(!list_empty(&req->queue));
291 	kfree(req);
292 }
293 
294 /*-------------------------------------------------------------------------*/
295 
296 static void
297 done(struct goku_ep *ep, struct goku_request *req, int status)
298 {
299 	struct goku_udc		*dev;
300 	unsigned		stopped = ep->stopped;
301 
302 	list_del_init(&req->queue);
303 
304 	if (likely(req->req.status == -EINPROGRESS))
305 		req->req.status = status;
306 	else
307 		status = req->req.status;
308 
309 	dev = ep->dev;
310 
311 	if (ep->dma)
312 		usb_gadget_unmap_request(&dev->gadget, &req->req, ep->is_in);
313 
314 #ifndef USB_TRACE
315 	if (status && status != -ESHUTDOWN)
316 #endif
317 		VDBG(dev, "complete %s req %p stat %d len %u/%u\n",
318 			ep->ep.name, &req->req, status,
319 			req->req.actual, req->req.length);
320 
321 	/* don't modify queue heads during completion callback */
322 	ep->stopped = 1;
323 	spin_unlock(&dev->lock);
324 	usb_gadget_giveback_request(&ep->ep, &req->req);
325 	spin_lock(&dev->lock);
326 	ep->stopped = stopped;
327 }
328 
329 /*-------------------------------------------------------------------------*/
330 
331 static inline int
332 write_packet(u32 __iomem *fifo, u8 *buf, struct goku_request *req, unsigned max)
333 {
334 	unsigned	length, count;
335 
336 	length = min(req->req.length - req->req.actual, max);
337 	req->req.actual += length;
338 
339 	count = length;
340 	while (likely(count--))
341 		writel(*buf++, fifo);
342 	return length;
343 }
344 
345 // return:  0 = still running, 1 = completed, negative = errno
346 static int write_fifo(struct goku_ep *ep, struct goku_request *req)
347 {
348 	struct goku_udc	*dev = ep->dev;
349 	u32		tmp;
350 	u8		*buf;
351 	unsigned	count;
352 	int		is_last;
353 
354 	tmp = readl(&dev->regs->DataSet);
355 	buf = req->req.buf + req->req.actual;
356 	prefetch(buf);
357 
358 	dev = ep->dev;
359 	if (unlikely(ep->num == 0 && dev->ep0state != EP0_IN))
360 		return -EL2HLT;
361 
362 	/* NOTE:  just single-buffered PIO-IN for now.  */
363 	if (unlikely((tmp & DATASET_A(ep->num)) != 0))
364 		return 0;
365 
366 	/* clear our "packet available" irq */
367 	if (ep->num != 0)
368 		writel(~INT_EPxDATASET(ep->num), &dev->regs->int_status);
369 
370 	count = write_packet(ep->reg_fifo, buf, req, ep->ep.maxpacket);
371 
372 	/* last packet often short (sometimes a zlp, especially on ep0) */
373 	if (unlikely(count != ep->ep.maxpacket)) {
374 		writel(~(1<<ep->num), &dev->regs->EOP);
375 		if (ep->num == 0) {
376 			dev->ep[0].stopped = 1;
377 			dev->ep0state = EP0_STATUS;
378 		}
379 		is_last = 1;
380 	} else {
381 		if (likely(req->req.length != req->req.actual)
382 				|| req->req.zero)
383 			is_last = 0;
384 		else
385 			is_last = 1;
386 	}
387 #if 0		/* printk seemed to trash is_last...*/
388 //#ifdef USB_TRACE
389 	VDBG(dev, "wrote %s %u bytes%s IN %u left %p\n",
390 		ep->ep.name, count, is_last ? "/last" : "",
391 		req->req.length - req->req.actual, req);
392 #endif
393 
394 	/* requests complete when all IN data is in the FIFO,
395 	 * or sometimes later, if a zlp was needed.
396 	 */
397 	if (is_last) {
398 		done(ep, req, 0);
399 		return 1;
400 	}
401 
402 	return 0;
403 }
404 
405 static int read_fifo(struct goku_ep *ep, struct goku_request *req)
406 {
407 	struct goku_udc_regs __iomem	*regs;
408 	u32				size, set;
409 	u8				*buf;
410 	unsigned			bufferspace, is_short, dbuff;
411 
412 	regs = ep->dev->regs;
413 top:
414 	buf = req->req.buf + req->req.actual;
415 	prefetchw(buf);
416 
417 	if (unlikely(ep->num == 0 && ep->dev->ep0state != EP0_OUT))
418 		return -EL2HLT;
419 
420 	dbuff = (ep->num == 1 || ep->num == 2);
421 	do {
422 		/* ack dataset irq matching the status we'll handle */
423 		if (ep->num != 0)
424 			writel(~INT_EPxDATASET(ep->num), &regs->int_status);
425 
426 		set = readl(&regs->DataSet) & DATASET_AB(ep->num);
427 		size = readl(&regs->EPxSizeLA[ep->num]);
428 		bufferspace = req->req.length - req->req.actual;
429 
430 		/* usually do nothing without an OUT packet */
431 		if (likely(ep->num != 0 || bufferspace != 0)) {
432 			if (unlikely(set == 0))
433 				break;
434 			/* use ep1/ep2 double-buffering for OUT */
435 			if (!(size & PACKET_ACTIVE))
436 				size = readl(&regs->EPxSizeLB[ep->num]);
437 			if (!(size & PACKET_ACTIVE))	/* "can't happen" */
438 				break;
439 			size &= DATASIZE;	/* EPxSizeH == 0 */
440 
441 		/* ep0out no-out-data case for set_config, etc */
442 		} else
443 			size = 0;
444 
445 		/* read all bytes from this packet */
446 		req->req.actual += size;
447 		is_short = (size < ep->ep.maxpacket);
448 #ifdef USB_TRACE
449 		VDBG(ep->dev, "read %s %u bytes%s OUT req %p %u/%u\n",
450 			ep->ep.name, size, is_short ? "/S" : "",
451 			req, req->req.actual, req->req.length);
452 #endif
453 		while (likely(size-- != 0)) {
454 			u8	byte = (u8) readl(ep->reg_fifo);
455 
456 			if (unlikely(bufferspace == 0)) {
457 				/* this happens when the driver's buffer
458 				 * is smaller than what the host sent.
459 				 * discard the extra data in this packet.
460 				 */
461 				if (req->req.status != -EOVERFLOW)
462 					DBG(ep->dev, "%s overflow %u\n",
463 						ep->ep.name, size);
464 				req->req.status = -EOVERFLOW;
465 			} else {
466 				*buf++ = byte;
467 				bufferspace--;
468 			}
469 		}
470 
471 		/* completion */
472 		if (unlikely(is_short || req->req.actual == req->req.length)) {
473 			if (unlikely(ep->num == 0)) {
474 				/* non-control endpoints now usable? */
475 				if (ep->dev->req_config)
476 					writel(ep->dev->configured
477 							? USBSTATE_CONFIGURED
478 							: 0,
479 						&regs->UsbState);
480 				/* ep0out status stage */
481 				writel(~(1<<0), &regs->EOP);
482 				ep->stopped = 1;
483 				ep->dev->ep0state = EP0_STATUS;
484 			}
485 			done(ep, req, 0);
486 
487 			/* empty the second buffer asap */
488 			if (dbuff && !list_empty(&ep->queue)) {
489 				req = list_entry(ep->queue.next,
490 						struct goku_request, queue);
491 				goto top;
492 			}
493 			return 1;
494 		}
495 	} while (dbuff);
496 	return 0;
497 }
498 
499 static inline void
500 pio_irq_enable(struct goku_udc *dev,
501 		struct goku_udc_regs __iomem *regs, int epnum)
502 {
503 	dev->int_enable |= INT_EPxDATASET (epnum);
504 	writel(dev->int_enable, &regs->int_enable);
505 	/* write may still be posted */
506 }
507 
508 static inline void
509 pio_irq_disable(struct goku_udc *dev,
510 		struct goku_udc_regs __iomem *regs, int epnum)
511 {
512 	dev->int_enable &= ~INT_EPxDATASET (epnum);
513 	writel(dev->int_enable, &regs->int_enable);
514 	/* write may still be posted */
515 }
516 
517 static inline void
518 pio_advance(struct goku_ep *ep)
519 {
520 	struct goku_request	*req;
521 
522 	if (unlikely(list_empty (&ep->queue)))
523 		return;
524 	req = list_entry(ep->queue.next, struct goku_request, queue);
525 	(ep->is_in ? write_fifo : read_fifo)(ep, req);
526 }
527 
528 
529 /*-------------------------------------------------------------------------*/
530 
531 // return:  0 = q running, 1 = q stopped, negative = errno
532 static int start_dma(struct goku_ep *ep, struct goku_request *req)
533 {
534 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
535 	u32				master;
536 	u32				start = req->req.dma;
537 	u32				end = start + req->req.length - 1;
538 
539 	master = readl(&regs->dma_master) & MST_RW_BITS;
540 
541 	/* re-init the bits affecting IN dma; careful with zlps */
542 	if (likely(ep->is_in)) {
543 		if (unlikely(master & MST_RD_ENA)) {
544 			DBG (ep->dev, "start, IN active dma %03x!!\n",
545 				master);
546 //			return -EL2HLT;
547 		}
548 		writel(end, &regs->in_dma_end);
549 		writel(start, &regs->in_dma_start);
550 
551 		master &= ~MST_R_BITS;
552 		if (unlikely(req->req.length == 0))
553 			master = MST_RD_ENA | MST_RD_EOPB;
554 		else if ((req->req.length % ep->ep.maxpacket) != 0
555 					|| req->req.zero)
556 			master = MST_RD_ENA | MST_EOPB_ENA;
557 		else
558 			master = MST_RD_ENA | MST_EOPB_DIS;
559 
560 		ep->dev->int_enable |= INT_MSTRDEND;
561 
562 	/* Goku DMA-OUT merges short packets, which plays poorly with
563 	 * protocols where short packets mark the transfer boundaries.
564 	 * The chip supports a nonstandard policy with INT_MSTWRTMOUT,
565 	 * ending transfers after 3 SOFs; we don't turn it on.
566 	 */
567 	} else {
568 		if (unlikely(master & MST_WR_ENA)) {
569 			DBG (ep->dev, "start, OUT active dma %03x!!\n",
570 				master);
571 //			return -EL2HLT;
572 		}
573 		writel(end, &regs->out_dma_end);
574 		writel(start, &regs->out_dma_start);
575 
576 		master &= ~MST_W_BITS;
577 		master |= MST_WR_ENA | MST_TIMEOUT_DIS;
578 
579 		ep->dev->int_enable |= INT_MSTWREND|INT_MSTWRTMOUT;
580 	}
581 
582 	writel(master, &regs->dma_master);
583 	writel(ep->dev->int_enable, &regs->int_enable);
584 	return 0;
585 }
586 
587 static void dma_advance(struct goku_udc *dev, struct goku_ep *ep)
588 {
589 	struct goku_request		*req;
590 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
591 	u32				master;
592 
593 	master = readl(&regs->dma_master);
594 
595 	if (unlikely(list_empty(&ep->queue))) {
596 stop:
597 		if (ep->is_in)
598 			dev->int_enable &= ~INT_MSTRDEND;
599 		else
600 			dev->int_enable &= ~(INT_MSTWREND|INT_MSTWRTMOUT);
601 		writel(dev->int_enable, &regs->int_enable);
602 		return;
603 	}
604 	req = list_entry(ep->queue.next, struct goku_request, queue);
605 
606 	/* normal hw dma completion (not abort) */
607 	if (likely(ep->is_in)) {
608 		if (unlikely(master & MST_RD_ENA))
609 			return;
610 		req->req.actual = readl(&regs->in_dma_current);
611 	} else {
612 		if (unlikely(master & MST_WR_ENA))
613 			return;
614 
615 		/* hardware merges short packets, and also hides packet
616 		 * overruns.  a partial packet MAY be in the fifo here.
617 		 */
618 		req->req.actual = readl(&regs->out_dma_current);
619 	}
620 	req->req.actual -= req->req.dma;
621 	req->req.actual++;
622 
623 #ifdef USB_TRACE
624 	VDBG(dev, "done %s %s dma, %u/%u bytes, req %p\n",
625 		ep->ep.name, ep->is_in ? "IN" : "OUT",
626 		req->req.actual, req->req.length, req);
627 #endif
628 	done(ep, req, 0);
629 	if (list_empty(&ep->queue))
630 		goto stop;
631 	req = list_entry(ep->queue.next, struct goku_request, queue);
632 	(void) start_dma(ep, req);
633 }
634 
635 static void abort_dma(struct goku_ep *ep, int status)
636 {
637 	struct goku_udc_regs __iomem	*regs = ep->dev->regs;
638 	struct goku_request		*req;
639 	u32				curr, master;
640 
641 	/* NAK future host requests, hoping the implicit delay lets the
642 	 * dma engine finish reading (or writing) its latest packet and
643 	 * empty the dma buffer (up to 16 bytes).
644 	 *
645 	 * This avoids needing to clean up a partial packet in the fifo;
646 	 * we can't do that for IN without side effects to HALT and TOGGLE.
647 	 */
648 	command(regs, COMMAND_FIFO_DISABLE, ep->num);
649 	req = list_entry(ep->queue.next, struct goku_request, queue);
650 	master = readl(&regs->dma_master) & MST_RW_BITS;
651 
652 	/* FIXME using these resets isn't usably documented. this may
653 	 * not work unless it's followed by disabling the endpoint.
654 	 *
655 	 * FIXME the OUT reset path doesn't even behave consistently.
656 	 */
657 	if (ep->is_in) {
658 		if (unlikely((readl(&regs->dma_master) & MST_RD_ENA) == 0))
659 			goto finished;
660 		curr = readl(&regs->in_dma_current);
661 
662 		writel(curr, &regs->in_dma_end);
663 		writel(curr, &regs->in_dma_start);
664 
665 		master &= ~MST_R_BITS;
666 		master |= MST_RD_RESET;
667 		writel(master, &regs->dma_master);
668 
669 		if (readl(&regs->dma_master) & MST_RD_ENA)
670 			DBG(ep->dev, "IN dma active after reset!\n");
671 
672 	} else {
673 		if (unlikely((readl(&regs->dma_master) & MST_WR_ENA) == 0))
674 			goto finished;
675 		curr = readl(&regs->out_dma_current);
676 
677 		writel(curr, &regs->out_dma_end);
678 		writel(curr, &regs->out_dma_start);
679 
680 		master &= ~MST_W_BITS;
681 		master |= MST_WR_RESET;
682 		writel(master, &regs->dma_master);
683 
684 		if (readl(&regs->dma_master) & MST_WR_ENA)
685 			DBG(ep->dev, "OUT dma active after reset!\n");
686 	}
687 	req->req.actual = (curr - req->req.dma) + 1;
688 	req->req.status = status;
689 
690 	VDBG(ep->dev, "%s %s %s %d/%d\n", __func__, ep->ep.name,
691 		ep->is_in ? "IN" : "OUT",
692 		req->req.actual, req->req.length);
693 
694 	command(regs, COMMAND_FIFO_ENABLE, ep->num);
695 
696 	return;
697 
698 finished:
699 	/* dma already completed; no abort needed */
700 	command(regs, COMMAND_FIFO_ENABLE, ep->num);
701 	req->req.actual = req->req.length;
702 	req->req.status = 0;
703 }
704 
705 /*-------------------------------------------------------------------------*/
706 
707 static int
708 goku_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags)
709 {
710 	struct goku_request	*req;
711 	struct goku_ep		*ep;
712 	struct goku_udc		*dev;
713 	unsigned long		flags;
714 	int			status;
715 
716 	/* always require a cpu-view buffer so pio works */
717 	req = container_of(_req, struct goku_request, req);
718 	if (unlikely(!_req || !_req->complete
719 			|| !_req->buf || !list_empty(&req->queue)))
720 		return -EINVAL;
721 	ep = container_of(_ep, struct goku_ep, ep);
722 	if (unlikely(!_ep || (!ep->ep.desc && ep->num != 0)))
723 		return -EINVAL;
724 	dev = ep->dev;
725 	if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN))
726 		return -ESHUTDOWN;
727 
728 	/* can't touch registers when suspended */
729 	if (dev->ep0state == EP0_SUSPEND)
730 		return -EBUSY;
731 
732 	/* set up dma mapping in case the caller didn't */
733 	if (ep->dma) {
734 		status = usb_gadget_map_request(&dev->gadget, &req->req,
735 				ep->is_in);
736 		if (status)
737 			return status;
738 	}
739 
740 #ifdef USB_TRACE
741 	VDBG(dev, "%s queue req %p, len %u buf %p\n",
742 			_ep->name, _req, _req->length, _req->buf);
743 #endif
744 
745 	spin_lock_irqsave(&dev->lock, flags);
746 
747 	_req->status = -EINPROGRESS;
748 	_req->actual = 0;
749 
750 	/* for ep0 IN without premature status, zlp is required and
751 	 * writing EOP starts the status stage (OUT).
752 	 */
753 	if (unlikely(ep->num == 0 && ep->is_in))
754 		_req->zero = 1;
755 
756 	/* kickstart this i/o queue? */
757 	status = 0;
758 	if (list_empty(&ep->queue) && likely(!ep->stopped)) {
759 		/* dma:  done after dma completion IRQ (or error)
760 		 * pio:  done after last fifo operation
761 		 */
762 		if (ep->dma)
763 			status = start_dma(ep, req);
764 		else
765 			status = (ep->is_in ? write_fifo : read_fifo)(ep, req);
766 
767 		if (unlikely(status != 0)) {
768 			if (status > 0)
769 				status = 0;
770 			req = NULL;
771 		}
772 
773 	} /* else pio or dma irq handler advances the queue. */
774 
775 	if (likely(req != NULL))
776 		list_add_tail(&req->queue, &ep->queue);
777 
778 	if (likely(!list_empty(&ep->queue))
779 			&& likely(ep->num != 0)
780 			&& !ep->dma
781 			&& !(dev->int_enable & INT_EPxDATASET (ep->num)))
782 		pio_irq_enable(dev, dev->regs, ep->num);
783 
784 	spin_unlock_irqrestore(&dev->lock, flags);
785 
786 	/* pci writes may still be posted */
787 	return status;
788 }
789 
790 /* dequeue ALL requests */
791 static void nuke(struct goku_ep *ep, int status)
792 {
793 	struct goku_request	*req;
794 
795 	ep->stopped = 1;
796 	if (list_empty(&ep->queue))
797 		return;
798 	if (ep->dma)
799 		abort_dma(ep, status);
800 	while (!list_empty(&ep->queue)) {
801 		req = list_entry(ep->queue.next, struct goku_request, queue);
802 		done(ep, req, status);
803 	}
804 }
805 
806 /* dequeue JUST ONE request */
807 static int goku_dequeue(struct usb_ep *_ep, struct usb_request *_req)
808 {
809 	struct goku_request	*req;
810 	struct goku_ep		*ep;
811 	struct goku_udc		*dev;
812 	unsigned long		flags;
813 
814 	ep = container_of(_ep, struct goku_ep, ep);
815 	if (!_ep || !_req || (!ep->ep.desc && ep->num != 0))
816 		return -EINVAL;
817 	dev = ep->dev;
818 	if (!dev->driver)
819 		return -ESHUTDOWN;
820 
821 	/* we can't touch (dma) registers when suspended */
822 	if (dev->ep0state == EP0_SUSPEND)
823 		return -EBUSY;
824 
825 	VDBG(dev, "%s %s %s %s %p\n", __func__, _ep->name,
826 		ep->is_in ? "IN" : "OUT",
827 		ep->dma ? "dma" : "pio",
828 		_req);
829 
830 	spin_lock_irqsave(&dev->lock, flags);
831 
832 	/* make sure it's actually queued on this endpoint */
833 	list_for_each_entry (req, &ep->queue, queue) {
834 		if (&req->req == _req)
835 			break;
836 	}
837 	if (&req->req != _req) {
838 		spin_unlock_irqrestore (&dev->lock, flags);
839 		return -EINVAL;
840 	}
841 
842 	if (ep->dma && ep->queue.next == &req->queue && !ep->stopped) {
843 		abort_dma(ep, -ECONNRESET);
844 		done(ep, req, -ECONNRESET);
845 		dma_advance(dev, ep);
846 	} else if (!list_empty(&req->queue))
847 		done(ep, req, -ECONNRESET);
848 	else
849 		req = NULL;
850 	spin_unlock_irqrestore(&dev->lock, flags);
851 
852 	return req ? 0 : -EOPNOTSUPP;
853 }
854 
855 /*-------------------------------------------------------------------------*/
856 
857 static void goku_clear_halt(struct goku_ep *ep)
858 {
859 	// assert (ep->num !=0)
860 	VDBG(ep->dev, "%s clear halt\n", ep->ep.name);
861 	command(ep->dev->regs, COMMAND_SETDATA0, ep->num);
862 	command(ep->dev->regs, COMMAND_STALL_CLEAR, ep->num);
863 	if (ep->stopped) {
864 		ep->stopped = 0;
865 		if (ep->dma) {
866 			struct goku_request	*req;
867 
868 			if (list_empty(&ep->queue))
869 				return;
870 			req = list_entry(ep->queue.next, struct goku_request,
871 						queue);
872 			(void) start_dma(ep, req);
873 		} else
874 			pio_advance(ep);
875 	}
876 }
877 
878 static int goku_set_halt(struct usb_ep *_ep, int value)
879 {
880 	struct goku_ep	*ep;
881 	unsigned long	flags;
882 	int		retval = 0;
883 
884 	if (!_ep)
885 		return -ENODEV;
886 	ep = container_of (_ep, struct goku_ep, ep);
887 
888 	if (ep->num == 0) {
889 		if (value) {
890 			ep->dev->ep0state = EP0_STALL;
891 			ep->dev->ep[0].stopped = 1;
892 		} else
893 			return -EINVAL;
894 
895 	/* don't change EPxSTATUS_EP_INVALID to READY */
896 	} else if (!ep->ep.desc) {
897 		DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
898 		return -EINVAL;
899 	}
900 
901 	spin_lock_irqsave(&ep->dev->lock, flags);
902 	if (!list_empty(&ep->queue))
903 		retval = -EAGAIN;
904 	else if (ep->is_in && value
905 			/* data in (either) packet buffer? */
906 			&& (readl(&ep->dev->regs->DataSet)
907 					& DATASET_AB(ep->num)))
908 		retval = -EAGAIN;
909 	else if (!value)
910 		goku_clear_halt(ep);
911 	else {
912 		ep->stopped = 1;
913 		VDBG(ep->dev, "%s set halt\n", ep->ep.name);
914 		command(ep->dev->regs, COMMAND_STALL, ep->num);
915 		readl(ep->reg_status);
916 	}
917 	spin_unlock_irqrestore(&ep->dev->lock, flags);
918 	return retval;
919 }
920 
921 static int goku_fifo_status(struct usb_ep *_ep)
922 {
923 	struct goku_ep			*ep;
924 	struct goku_udc_regs __iomem	*regs;
925 	u32				size;
926 
927 	if (!_ep)
928 		return -ENODEV;
929 	ep = container_of(_ep, struct goku_ep, ep);
930 
931 	/* size is only reported sanely for OUT */
932 	if (ep->is_in)
933 		return -EOPNOTSUPP;
934 
935 	/* ignores 16-byte dma buffer; SizeH == 0 */
936 	regs = ep->dev->regs;
937 	size = readl(&regs->EPxSizeLA[ep->num]) & DATASIZE;
938 	size += readl(&regs->EPxSizeLB[ep->num]) & DATASIZE;
939 	VDBG(ep->dev, "%s %s %u\n", __func__, ep->ep.name, size);
940 	return size;
941 }
942 
943 static void goku_fifo_flush(struct usb_ep *_ep)
944 {
945 	struct goku_ep			*ep;
946 	struct goku_udc_regs __iomem	*regs;
947 	u32				size;
948 
949 	if (!_ep)
950 		return;
951 	ep = container_of(_ep, struct goku_ep, ep);
952 	VDBG(ep->dev, "%s %s\n", __func__, ep->ep.name);
953 
954 	/* don't change EPxSTATUS_EP_INVALID to READY */
955 	if (!ep->ep.desc && ep->num != 0) {
956 		DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
957 		return;
958 	}
959 
960 	regs = ep->dev->regs;
961 	size = readl(&regs->EPxSizeLA[ep->num]);
962 	size &= DATASIZE;
963 
964 	/* Non-desirable behavior:  FIFO_CLEAR also clears the
965 	 * endpoint halt feature.  For OUT, we _could_ just read
966 	 * the bytes out (PIO, if !ep->dma); for in, no choice.
967 	 */
968 	if (size)
969 		command(regs, COMMAND_FIFO_CLEAR, ep->num);
970 }
971 
972 static const struct usb_ep_ops goku_ep_ops = {
973 	.enable		= goku_ep_enable,
974 	.disable	= goku_ep_disable,
975 
976 	.alloc_request	= goku_alloc_request,
977 	.free_request	= goku_free_request,
978 
979 	.queue		= goku_queue,
980 	.dequeue	= goku_dequeue,
981 
982 	.set_halt	= goku_set_halt,
983 	.fifo_status	= goku_fifo_status,
984 	.fifo_flush	= goku_fifo_flush,
985 };
986 
987 /*-------------------------------------------------------------------------*/
988 
989 static int goku_get_frame(struct usb_gadget *_gadget)
990 {
991 	return -EOPNOTSUPP;
992 }
993 
994 static struct usb_ep *goku_match_ep(struct usb_gadget *g,
995 		struct usb_endpoint_descriptor *desc,
996 		struct usb_ss_ep_comp_descriptor *ep_comp)
997 {
998 	struct goku_udc	*dev = to_goku_udc(g);
999 	struct usb_ep *ep;
1000 
1001 	switch (usb_endpoint_type(desc)) {
1002 	case USB_ENDPOINT_XFER_INT:
1003 		/* single buffering is enough */
1004 		ep = &dev->ep[3].ep;
1005 		if (usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1006 			return ep;
1007 		break;
1008 	case USB_ENDPOINT_XFER_BULK:
1009 		if (usb_endpoint_dir_in(desc)) {
1010 			/* DMA may be available */
1011 			ep = &dev->ep[2].ep;
1012 			if (usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1013 				return ep;
1014 		}
1015 		break;
1016 	default:
1017 		/* nothing */ ;
1018 	}
1019 
1020 	return NULL;
1021 }
1022 
1023 static int goku_udc_start(struct usb_gadget *g,
1024 		struct usb_gadget_driver *driver);
1025 static int goku_udc_stop(struct usb_gadget *g);
1026 
1027 static const struct usb_gadget_ops goku_ops = {
1028 	.get_frame	= goku_get_frame,
1029 	.udc_start	= goku_udc_start,
1030 	.udc_stop	= goku_udc_stop,
1031 	.match_ep	= goku_match_ep,
1032 	// no remote wakeup
1033 	// not selfpowered
1034 };
1035 
1036 /*-------------------------------------------------------------------------*/
1037 
1038 static inline const char *dmastr(void)
1039 {
1040 	if (use_dma == 0)
1041 		return "(dma disabled)";
1042 	else if (use_dma == 2)
1043 		return "(dma IN and OUT)";
1044 	else
1045 		return "(dma IN)";
1046 }
1047 
1048 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1049 
1050 static const char proc_node_name [] = "driver/udc";
1051 
1052 #define FOURBITS "%s%s%s%s"
1053 #define EIGHTBITS FOURBITS FOURBITS
1054 
1055 static void dump_intmask(struct seq_file *m, const char *label, u32 mask)
1056 {
1057 	/* int_status is the same format ... */
1058 	seq_printf(m, "%s %05X =" FOURBITS EIGHTBITS EIGHTBITS "\n",
1059 		   label, mask,
1060 		   (mask & INT_PWRDETECT) ? " power" : "",
1061 		   (mask & INT_SYSERROR) ? " sys" : "",
1062 		   (mask & INT_MSTRDEND) ? " in-dma" : "",
1063 		   (mask & INT_MSTWRTMOUT) ? " wrtmo" : "",
1064 
1065 		   (mask & INT_MSTWREND) ? " out-dma" : "",
1066 		   (mask & INT_MSTWRSET) ? " wrset" : "",
1067 		   (mask & INT_ERR) ? " err" : "",
1068 		   (mask & INT_SOF) ? " sof" : "",
1069 
1070 		   (mask & INT_EP3NAK) ? " ep3nak" : "",
1071 		   (mask & INT_EP2NAK) ? " ep2nak" : "",
1072 		   (mask & INT_EP1NAK) ? " ep1nak" : "",
1073 		   (mask & INT_EP3DATASET) ? " ep3" : "",
1074 
1075 		   (mask & INT_EP2DATASET) ? " ep2" : "",
1076 		   (mask & INT_EP1DATASET) ? " ep1" : "",
1077 		   (mask & INT_STATUSNAK) ? " ep0snak" : "",
1078 		   (mask & INT_STATUS) ? " ep0status" : "",
1079 
1080 		   (mask & INT_SETUP) ? " setup" : "",
1081 		   (mask & INT_ENDPOINT0) ? " ep0" : "",
1082 		   (mask & INT_USBRESET) ? " reset" : "",
1083 		   (mask & INT_SUSPEND) ? " suspend" : "");
1084 }
1085 
1086 static const char *udc_ep_state(enum ep0state state)
1087 {
1088 	switch (state) {
1089 	case EP0_DISCONNECT:
1090 		return "ep0_disconnect";
1091 	case EP0_IDLE:
1092 		return "ep0_idle";
1093 	case EP0_IN:
1094 		return "ep0_in";
1095 	case EP0_OUT:
1096 		return "ep0_out";
1097 	case EP0_STATUS:
1098 		return "ep0_status";
1099 	case EP0_STALL:
1100 		return "ep0_stall";
1101 	case EP0_SUSPEND:
1102 		return "ep0_suspend";
1103 	}
1104 
1105 	return "ep0_?";
1106 }
1107 
1108 static const char *udc_ep_status(u32 status)
1109 {
1110 	switch (status & EPxSTATUS_EP_MASK) {
1111 	case EPxSTATUS_EP_READY:
1112 		return "ready";
1113 	case EPxSTATUS_EP_DATAIN:
1114 		return "packet";
1115 	case EPxSTATUS_EP_FULL:
1116 		return "full";
1117 	case EPxSTATUS_EP_TX_ERR:	/* host will retry */
1118 		return "tx_err";
1119 	case EPxSTATUS_EP_RX_ERR:
1120 		return "rx_err";
1121 	case EPxSTATUS_EP_BUSY:		/* ep0 only */
1122 		return "busy";
1123 	case EPxSTATUS_EP_STALL:
1124 		return "stall";
1125 	case EPxSTATUS_EP_INVALID:	/* these "can't happen" */
1126 		return "invalid";
1127 	}
1128 
1129 	return "?";
1130 }
1131 
1132 static int udc_proc_read(struct seq_file *m, void *v)
1133 {
1134 	struct goku_udc			*dev = m->private;
1135 	struct goku_udc_regs __iomem	*regs = dev->regs;
1136 	unsigned long			flags;
1137 	int				i, is_usb_connected;
1138 	u32				tmp;
1139 
1140 	local_irq_save(flags);
1141 
1142 	/* basic device status */
1143 	tmp = readl(&regs->power_detect);
1144 	is_usb_connected = tmp & PW_DETECT;
1145 	seq_printf(m,
1146 		   "%s - %s\n"
1147 		   "%s version: %s %s\n"
1148 		   "Gadget driver: %s\n"
1149 		   "Host %s, %s\n"
1150 		   "\n",
1151 		   pci_name(dev->pdev), driver_desc,
1152 		   driver_name, DRIVER_VERSION, dmastr(),
1153 		   dev->driver ? dev->driver->driver.name : "(none)",
1154 		   is_usb_connected
1155 			   ? ((tmp & PW_PULLUP) ? "full speed" : "powered")
1156 			   : "disconnected",
1157 		   udc_ep_state(dev->ep0state));
1158 
1159 	dump_intmask(m, "int_status", readl(&regs->int_status));
1160 	dump_intmask(m, "int_enable", readl(&regs->int_enable));
1161 
1162 	if (!is_usb_connected || !dev->driver || (tmp & PW_PULLUP) == 0)
1163 		goto done;
1164 
1165 	/* registers for (active) device and ep0 */
1166 	seq_printf(m, "\nirqs %lu\ndataset %02x single.bcs %02x.%02x state %x addr %u\n",
1167 		   dev->irqs, readl(&regs->DataSet),
1168 		   readl(&regs->EPxSingle), readl(&regs->EPxBCS),
1169 		   readl(&regs->UsbState),
1170 		   readl(&regs->address));
1171 	if (seq_has_overflowed(m))
1172 		goto done;
1173 
1174 	tmp = readl(&regs->dma_master);
1175 	seq_printf(m, "dma %03X =" EIGHTBITS "%s %s\n",
1176 		   tmp,
1177 		   (tmp & MST_EOPB_DIS) ? " eopb-" : "",
1178 		   (tmp & MST_EOPB_ENA) ? " eopb+" : "",
1179 		   (tmp & MST_TIMEOUT_DIS) ? " tmo-" : "",
1180 		   (tmp & MST_TIMEOUT_ENA) ? " tmo+" : "",
1181 
1182 		   (tmp & MST_RD_EOPB) ? " eopb" : "",
1183 		   (tmp & MST_RD_RESET) ? " in_reset" : "",
1184 		   (tmp & MST_WR_RESET) ? " out_reset" : "",
1185 		   (tmp & MST_RD_ENA) ? " IN" : "",
1186 
1187 		   (tmp & MST_WR_ENA) ? " OUT" : "",
1188 		   (tmp & MST_CONNECTION) ? "ep1in/ep2out" : "ep1out/ep2in");
1189 	if (seq_has_overflowed(m))
1190 		goto done;
1191 
1192 	/* dump endpoint queues */
1193 	for (i = 0; i < 4; i++) {
1194 		struct goku_ep		*ep = &dev->ep [i];
1195 		struct goku_request	*req;
1196 
1197 		if (i && !ep->ep.desc)
1198 			continue;
1199 
1200 		tmp = readl(ep->reg_status);
1201 		seq_printf(m, "%s %s max %u %s, irqs %lu, status %02x (%s) " FOURBITS "\n",
1202 			   ep->ep.name,
1203 			   ep->is_in ? "in" : "out",
1204 			   ep->ep.maxpacket,
1205 			   ep->dma ? "dma" : "pio",
1206 			   ep->irqs,
1207 			   tmp, udc_ep_status(tmp),
1208 			   (tmp & EPxSTATUS_TOGGLE) ? "data1" : "data0",
1209 			   (tmp & EPxSTATUS_SUSPEND) ? " suspend" : "",
1210 			   (tmp & EPxSTATUS_FIFO_DISABLE) ? " disable" : "",
1211 			   (tmp & EPxSTATUS_STAGE_ERROR) ? " ep0stat" : "");
1212 		if (seq_has_overflowed(m))
1213 			goto done;
1214 
1215 		if (list_empty(&ep->queue)) {
1216 			seq_puts(m, "\t(nothing queued)\n");
1217 			if (seq_has_overflowed(m))
1218 				goto done;
1219 			continue;
1220 		}
1221 		list_for_each_entry(req, &ep->queue, queue) {
1222 			if (ep->dma && req->queue.prev == &ep->queue) {
1223 				if (i == UDC_MSTRD_ENDPOINT)
1224 					tmp = readl(&regs->in_dma_current);
1225 				else
1226 					tmp = readl(&regs->out_dma_current);
1227 				tmp -= req->req.dma;
1228 				tmp++;
1229 			} else
1230 				tmp = req->req.actual;
1231 
1232 			seq_printf(m, "\treq %p len %u/%u buf %p\n",
1233 				   &req->req, tmp, req->req.length,
1234 				   req->req.buf);
1235 			if (seq_has_overflowed(m))
1236 				goto done;
1237 		}
1238 	}
1239 
1240 done:
1241 	local_irq_restore(flags);
1242 	return 0;
1243 }
1244 #endif	/* CONFIG_USB_GADGET_DEBUG_FILES */
1245 
1246 /*-------------------------------------------------------------------------*/
1247 
1248 static void udc_reinit (struct goku_udc *dev)
1249 {
1250 	static char *names [] = { "ep0", "ep1-bulk", "ep2-bulk", "ep3-bulk" };
1251 
1252 	unsigned i;
1253 
1254 	INIT_LIST_HEAD (&dev->gadget.ep_list);
1255 	dev->gadget.ep0 = &dev->ep [0].ep;
1256 	dev->gadget.speed = USB_SPEED_UNKNOWN;
1257 	dev->ep0state = EP0_DISCONNECT;
1258 	dev->irqs = 0;
1259 
1260 	for (i = 0; i < 4; i++) {
1261 		struct goku_ep	*ep = &dev->ep[i];
1262 
1263 		ep->num = i;
1264 		ep->ep.name = names[i];
1265 		ep->reg_fifo = &dev->regs->ep_fifo [i];
1266 		ep->reg_status = &dev->regs->ep_status [i];
1267 		ep->reg_mode = &dev->regs->ep_mode[i];
1268 
1269 		ep->ep.ops = &goku_ep_ops;
1270 		list_add_tail (&ep->ep.ep_list, &dev->gadget.ep_list);
1271 		ep->dev = dev;
1272 		INIT_LIST_HEAD (&ep->queue);
1273 
1274 		ep_reset(NULL, ep);
1275 
1276 		if (i == 0)
1277 			ep->ep.caps.type_control = true;
1278 		else
1279 			ep->ep.caps.type_bulk = true;
1280 
1281 		ep->ep.caps.dir_in = true;
1282 		ep->ep.caps.dir_out = true;
1283 	}
1284 
1285 	dev->ep[0].reg_mode = NULL;
1286 	usb_ep_set_maxpacket_limit(&dev->ep[0].ep, MAX_EP0_SIZE);
1287 	list_del_init (&dev->ep[0].ep.ep_list);
1288 }
1289 
1290 static void udc_reset(struct goku_udc *dev)
1291 {
1292 	struct goku_udc_regs __iomem	*regs = dev->regs;
1293 
1294 	writel(0, &regs->power_detect);
1295 	writel(0, &regs->int_enable);
1296 	readl(&regs->int_enable);
1297 	dev->int_enable = 0;
1298 
1299 	/* deassert reset, leave USB D+ at hi-Z (no pullup)
1300 	 * don't let INT_PWRDETECT sequence begin
1301 	 */
1302 	udelay(250);
1303 	writel(PW_RESETB, &regs->power_detect);
1304 	readl(&regs->int_enable);
1305 }
1306 
1307 static void ep0_start(struct goku_udc *dev)
1308 {
1309 	struct goku_udc_regs __iomem	*regs = dev->regs;
1310 	unsigned			i;
1311 
1312 	VDBG(dev, "%s\n", __func__);
1313 
1314 	udc_reset(dev);
1315 	udc_reinit (dev);
1316 	//writel(MST_EOPB_ENA | MST_TIMEOUT_ENA, &regs->dma_master);
1317 
1318 	/* hw handles set_address, set_feature, get_status; maybe more */
1319 	writel(   G_REQMODE_SET_INTF | G_REQMODE_GET_INTF
1320 		| G_REQMODE_SET_CONF | G_REQMODE_GET_CONF
1321 		| G_REQMODE_GET_DESC
1322 		| G_REQMODE_CLEAR_FEAT
1323 		, &regs->reqmode);
1324 
1325 	for (i = 0; i < 4; i++)
1326 		dev->ep[i].irqs = 0;
1327 
1328 	/* can't modify descriptors after writing UsbReady */
1329 	for (i = 0; i < DESC_LEN; i++)
1330 		writel(0, &regs->descriptors[i]);
1331 	writel(0, &regs->UsbReady);
1332 
1333 	/* expect ep0 requests when the host drops reset */
1334 	writel(PW_RESETB | PW_PULLUP, &regs->power_detect);
1335 	dev->int_enable = INT_DEVWIDE | INT_EP0;
1336 	writel(dev->int_enable, &dev->regs->int_enable);
1337 	readl(&regs->int_enable);
1338 	dev->gadget.speed = USB_SPEED_FULL;
1339 	dev->ep0state = EP0_IDLE;
1340 }
1341 
1342 static void udc_enable(struct goku_udc *dev)
1343 {
1344 	/* start enumeration now, or after power detect irq */
1345 	if (readl(&dev->regs->power_detect) & PW_DETECT)
1346 		ep0_start(dev);
1347 	else {
1348 		DBG(dev, "%s\n", __func__);
1349 		dev->int_enable = INT_PWRDETECT;
1350 		writel(dev->int_enable, &dev->regs->int_enable);
1351 	}
1352 }
1353 
1354 /*-------------------------------------------------------------------------*/
1355 
1356 /* keeping it simple:
1357  * - one bus driver, initted first;
1358  * - one function driver, initted second
1359  */
1360 
1361 /* when a driver is successfully registered, it will receive
1362  * control requests including set_configuration(), which enables
1363  * non-control requests.  then usb traffic follows until a
1364  * disconnect is reported.  then a host may connect again, or
1365  * the driver might get unbound.
1366  */
1367 static int goku_udc_start(struct usb_gadget *g,
1368 		struct usb_gadget_driver *driver)
1369 {
1370 	struct goku_udc	*dev = to_goku_udc(g);
1371 
1372 	/* hook up the driver */
1373 	driver->driver.bus = NULL;
1374 	dev->driver = driver;
1375 
1376 	/*
1377 	 * then enable host detection and ep0; and we're ready
1378 	 * for set_configuration as well as eventual disconnect.
1379 	 */
1380 	udc_enable(dev);
1381 
1382 	return 0;
1383 }
1384 
1385 static void stop_activity(struct goku_udc *dev)
1386 {
1387 	unsigned	i;
1388 
1389 	DBG (dev, "%s\n", __func__);
1390 
1391 	/* disconnect gadget driver after quiesceing hw and the driver */
1392 	udc_reset (dev);
1393 	for (i = 0; i < 4; i++)
1394 		nuke(&dev->ep [i], -ESHUTDOWN);
1395 
1396 	if (dev->driver)
1397 		udc_enable(dev);
1398 }
1399 
1400 static int goku_udc_stop(struct usb_gadget *g)
1401 {
1402 	struct goku_udc	*dev = to_goku_udc(g);
1403 	unsigned long	flags;
1404 
1405 	spin_lock_irqsave(&dev->lock, flags);
1406 	dev->driver = NULL;
1407 	stop_activity(dev);
1408 	spin_unlock_irqrestore(&dev->lock, flags);
1409 
1410 	return 0;
1411 }
1412 
1413 /*-------------------------------------------------------------------------*/
1414 
1415 static void ep0_setup(struct goku_udc *dev)
1416 {
1417 	struct goku_udc_regs __iomem	*regs = dev->regs;
1418 	struct usb_ctrlrequest		ctrl;
1419 	int				tmp;
1420 
1421 	/* read SETUP packet and enter DATA stage */
1422 	ctrl.bRequestType = readl(&regs->bRequestType);
1423 	ctrl.bRequest = readl(&regs->bRequest);
1424 	ctrl.wValue  = cpu_to_le16((readl(&regs->wValueH)  << 8)
1425 					| readl(&regs->wValueL));
1426 	ctrl.wIndex  = cpu_to_le16((readl(&regs->wIndexH)  << 8)
1427 					| readl(&regs->wIndexL));
1428 	ctrl.wLength = cpu_to_le16((readl(&regs->wLengthH) << 8)
1429 					| readl(&regs->wLengthL));
1430 	writel(0, &regs->SetupRecv);
1431 
1432 	nuke(&dev->ep[0], 0);
1433 	dev->ep[0].stopped = 0;
1434 	if (likely(ctrl.bRequestType & USB_DIR_IN)) {
1435 		dev->ep[0].is_in = 1;
1436 		dev->ep0state = EP0_IN;
1437 		/* detect early status stages */
1438 		writel(ICONTROL_STATUSNAK, &dev->regs->IntControl);
1439 	} else {
1440 		dev->ep[0].is_in = 0;
1441 		dev->ep0state = EP0_OUT;
1442 
1443 		/* NOTE:  CLEAR_FEATURE is done in software so that we can
1444 		 * synchronize transfer restarts after bulk IN stalls.  data
1445 		 * won't even enter the fifo until the halt is cleared.
1446 		 */
1447 		switch (ctrl.bRequest) {
1448 		case USB_REQ_CLEAR_FEATURE:
1449 			switch (ctrl.bRequestType) {
1450 			case USB_RECIP_ENDPOINT:
1451 				tmp = le16_to_cpu(ctrl.wIndex) & 0x0f;
1452 				/* active endpoint */
1453 				if (tmp > 3 ||
1454 				    (!dev->ep[tmp].ep.desc && tmp != 0))
1455 					goto stall;
1456 				if (ctrl.wIndex & cpu_to_le16(
1457 						USB_DIR_IN)) {
1458 					if (!dev->ep[tmp].is_in)
1459 						goto stall;
1460 				} else {
1461 					if (dev->ep[tmp].is_in)
1462 						goto stall;
1463 				}
1464 				if (ctrl.wValue != cpu_to_le16(
1465 						USB_ENDPOINT_HALT))
1466 					goto stall;
1467 				if (tmp)
1468 					goku_clear_halt(&dev->ep[tmp]);
1469 succeed:
1470 				/* start ep0out status stage */
1471 				writel(~(1<<0), &regs->EOP);
1472 				dev->ep[0].stopped = 1;
1473 				dev->ep0state = EP0_STATUS;
1474 				return;
1475 			case USB_RECIP_DEVICE:
1476 				/* device remote wakeup: always clear */
1477 				if (ctrl.wValue != cpu_to_le16(1))
1478 					goto stall;
1479 				VDBG(dev, "clear dev remote wakeup\n");
1480 				goto succeed;
1481 			case USB_RECIP_INTERFACE:
1482 				goto stall;
1483 			default:		/* pass to gadget driver */
1484 				break;
1485 			}
1486 			break;
1487 		default:
1488 			break;
1489 		}
1490 	}
1491 
1492 #ifdef USB_TRACE
1493 	VDBG(dev, "SETUP %02x.%02x v%04x i%04x l%04x\n",
1494 		ctrl.bRequestType, ctrl.bRequest,
1495 		le16_to_cpu(ctrl.wValue), le16_to_cpu(ctrl.wIndex),
1496 		le16_to_cpu(ctrl.wLength));
1497 #endif
1498 
1499 	/* hw wants to know when we're configured (or not) */
1500 	dev->req_config = (ctrl.bRequest == USB_REQ_SET_CONFIGURATION
1501 				&& ctrl.bRequestType == USB_RECIP_DEVICE);
1502 	if (unlikely(dev->req_config))
1503 		dev->configured = (ctrl.wValue != cpu_to_le16(0));
1504 
1505 	/* delegate everything to the gadget driver.
1506 	 * it may respond after this irq handler returns.
1507 	 */
1508 	spin_unlock (&dev->lock);
1509 	tmp = dev->driver->setup(&dev->gadget, &ctrl);
1510 	spin_lock (&dev->lock);
1511 	if (unlikely(tmp < 0)) {
1512 stall:
1513 #ifdef USB_TRACE
1514 		VDBG(dev, "req %02x.%02x protocol STALL; err %d\n",
1515 				ctrl.bRequestType, ctrl.bRequest, tmp);
1516 #endif
1517 		command(regs, COMMAND_STALL, 0);
1518 		dev->ep[0].stopped = 1;
1519 		dev->ep0state = EP0_STALL;
1520 	}
1521 
1522 	/* expect at least one data or status stage irq */
1523 }
1524 
1525 #define ACK(irqbit) { \
1526 		stat &= ~irqbit; \
1527 		writel(~irqbit, &regs->int_status); \
1528 		handled = 1; \
1529 		}
1530 
1531 static irqreturn_t goku_irq(int irq, void *_dev)
1532 {
1533 	struct goku_udc			*dev = _dev;
1534 	struct goku_udc_regs __iomem	*regs = dev->regs;
1535 	struct goku_ep			*ep;
1536 	u32				stat, handled = 0;
1537 	unsigned			i, rescans = 5;
1538 
1539 	spin_lock(&dev->lock);
1540 
1541 rescan:
1542 	stat = readl(&regs->int_status) & dev->int_enable;
1543         if (!stat)
1544 		goto done;
1545 	dev->irqs++;
1546 
1547 	/* device-wide irqs */
1548 	if (unlikely(stat & INT_DEVWIDE)) {
1549 		if (stat & INT_SYSERROR) {
1550 			ERROR(dev, "system error\n");
1551 			stop_activity(dev);
1552 			stat = 0;
1553 			handled = 1;
1554 			// FIXME have a neater way to prevent re-enumeration
1555 			dev->driver = NULL;
1556 			goto done;
1557 		}
1558 		if (stat & INT_PWRDETECT) {
1559 			writel(~stat, &regs->int_status);
1560 			if (readl(&dev->regs->power_detect) & PW_DETECT) {
1561 				VDBG(dev, "connect\n");
1562 				ep0_start(dev);
1563 			} else {
1564 				DBG(dev, "disconnect\n");
1565 				if (dev->gadget.speed == USB_SPEED_FULL)
1566 					stop_activity(dev);
1567 				dev->ep0state = EP0_DISCONNECT;
1568 				dev->int_enable = INT_DEVWIDE;
1569 				writel(dev->int_enable, &dev->regs->int_enable);
1570 			}
1571 			stat = 0;
1572 			handled = 1;
1573 			goto done;
1574 		}
1575 		if (stat & INT_SUSPEND) {
1576 			ACK(INT_SUSPEND);
1577 			if (readl(&regs->ep_status[0]) & EPxSTATUS_SUSPEND) {
1578 				switch (dev->ep0state) {
1579 				case EP0_DISCONNECT:
1580 				case EP0_SUSPEND:
1581 					goto pm_next;
1582 				default:
1583 					break;
1584 				}
1585 				DBG(dev, "USB suspend\n");
1586 				dev->ep0state = EP0_SUSPEND;
1587 				if (dev->gadget.speed != USB_SPEED_UNKNOWN
1588 						&& dev->driver
1589 						&& dev->driver->suspend) {
1590 					spin_unlock(&dev->lock);
1591 					dev->driver->suspend(&dev->gadget);
1592 					spin_lock(&dev->lock);
1593 				}
1594 			} else {
1595 				if (dev->ep0state != EP0_SUSPEND) {
1596 					DBG(dev, "bogus USB resume %d\n",
1597 						dev->ep0state);
1598 					goto pm_next;
1599 				}
1600 				DBG(dev, "USB resume\n");
1601 				dev->ep0state = EP0_IDLE;
1602 				if (dev->gadget.speed != USB_SPEED_UNKNOWN
1603 						&& dev->driver
1604 						&& dev->driver->resume) {
1605 					spin_unlock(&dev->lock);
1606 					dev->driver->resume(&dev->gadget);
1607 					spin_lock(&dev->lock);
1608 				}
1609 			}
1610 		}
1611 pm_next:
1612 		if (stat & INT_USBRESET) {		/* hub reset done */
1613 			ACK(INT_USBRESET);
1614 			INFO(dev, "USB reset done, gadget %s\n",
1615 				dev->driver->driver.name);
1616 		}
1617 		// and INT_ERR on some endpoint's crc/bitstuff/... problem
1618 	}
1619 
1620 	/* progress ep0 setup, data, or status stages.
1621 	 * no transition {EP0_STATUS, EP0_STALL} --> EP0_IDLE; saves irqs
1622 	 */
1623 	if (stat & INT_SETUP) {
1624 		ACK(INT_SETUP);
1625 		dev->ep[0].irqs++;
1626 		ep0_setup(dev);
1627 	}
1628         if (stat & INT_STATUSNAK) {
1629 		ACK(INT_STATUSNAK|INT_ENDPOINT0);
1630 		if (dev->ep0state == EP0_IN) {
1631 			ep = &dev->ep[0];
1632 			ep->irqs++;
1633 			nuke(ep, 0);
1634 			writel(~(1<<0), &regs->EOP);
1635 			dev->ep0state = EP0_STATUS;
1636 		}
1637 	}
1638         if (stat & INT_ENDPOINT0) {
1639 		ACK(INT_ENDPOINT0);
1640 		ep = &dev->ep[0];
1641 		ep->irqs++;
1642 		pio_advance(ep);
1643         }
1644 
1645 	/* dma completion */
1646         if (stat & INT_MSTRDEND) {	/* IN */
1647 		ACK(INT_MSTRDEND);
1648 		ep = &dev->ep[UDC_MSTRD_ENDPOINT];
1649 		ep->irqs++;
1650 		dma_advance(dev, ep);
1651         }
1652         if (stat & INT_MSTWREND) {	/* OUT */
1653 		ACK(INT_MSTWREND);
1654 		ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1655 		ep->irqs++;
1656 		dma_advance(dev, ep);
1657         }
1658         if (stat & INT_MSTWRTMOUT) {	/* OUT */
1659 		ACK(INT_MSTWRTMOUT);
1660 		ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1661 		ep->irqs++;
1662 		ERROR(dev, "%s write timeout ?\n", ep->ep.name);
1663 		// reset dma? then dma_advance()
1664         }
1665 
1666 	/* pio */
1667 	for (i = 1; i < 4; i++) {
1668 		u32		tmp = INT_EPxDATASET(i);
1669 
1670 		if (!(stat & tmp))
1671 			continue;
1672 		ep = &dev->ep[i];
1673 		pio_advance(ep);
1674 		if (list_empty (&ep->queue))
1675 			pio_irq_disable(dev, regs, i);
1676 		stat &= ~tmp;
1677 		handled = 1;
1678 		ep->irqs++;
1679 	}
1680 
1681 	if (rescans--)
1682 		goto rescan;
1683 
1684 done:
1685 	(void)readl(&regs->int_enable);
1686 	spin_unlock(&dev->lock);
1687 	if (stat)
1688 		DBG(dev, "unhandled irq status: %05x (%05x, %05x)\n", stat,
1689 				readl(&regs->int_status), dev->int_enable);
1690 	return IRQ_RETVAL(handled);
1691 }
1692 
1693 #undef ACK
1694 
1695 /*-------------------------------------------------------------------------*/
1696 
1697 static void gadget_release(struct device *_dev)
1698 {
1699 	struct goku_udc	*dev = dev_get_drvdata(_dev);
1700 
1701 	kfree(dev);
1702 }
1703 
1704 /* tear down the binding between this driver and the pci device */
1705 
1706 static void goku_remove(struct pci_dev *pdev)
1707 {
1708 	struct goku_udc		*dev = pci_get_drvdata(pdev);
1709 
1710 	DBG(dev, "%s\n", __func__);
1711 
1712 	usb_del_gadget_udc(&dev->gadget);
1713 
1714 	BUG_ON(dev->driver);
1715 
1716 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1717 	remove_proc_entry(proc_node_name, NULL);
1718 #endif
1719 	if (dev->regs)
1720 		udc_reset(dev);
1721 	if (dev->got_irq)
1722 		free_irq(pdev->irq, dev);
1723 	if (dev->regs)
1724 		iounmap(dev->regs);
1725 	if (dev->got_region)
1726 		release_mem_region(pci_resource_start (pdev, 0),
1727 				pci_resource_len (pdev, 0));
1728 	if (dev->enabled)
1729 		pci_disable_device(pdev);
1730 
1731 	dev->regs = NULL;
1732 
1733 	INFO(dev, "unbind\n");
1734 }
1735 
1736 /* wrap this driver around the specified pci device, but
1737  * don't respond over USB until a gadget driver binds to us.
1738  */
1739 
1740 static int goku_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1741 {
1742 	struct goku_udc		*dev = NULL;
1743 	unsigned long		resource, len;
1744 	void __iomem		*base = NULL;
1745 	int			retval;
1746 
1747 	if (!pdev->irq) {
1748 		printk(KERN_ERR "Check PCI %s IRQ setup!\n", pci_name(pdev));
1749 		retval = -ENODEV;
1750 		goto err;
1751 	}
1752 
1753 	/* alloc, and start init */
1754 	dev = kzalloc (sizeof *dev, GFP_KERNEL);
1755 	if (!dev) {
1756 		retval = -ENOMEM;
1757 		goto err;
1758 	}
1759 
1760 	spin_lock_init(&dev->lock);
1761 	dev->pdev = pdev;
1762 	dev->gadget.ops = &goku_ops;
1763 	dev->gadget.max_speed = USB_SPEED_FULL;
1764 
1765 	/* the "gadget" abstracts/virtualizes the controller */
1766 	dev->gadget.name = driver_name;
1767 
1768 	/* now all the pci goodies ... */
1769 	retval = pci_enable_device(pdev);
1770 	if (retval < 0) {
1771 		DBG(dev, "can't enable, %d\n", retval);
1772 		goto err;
1773 	}
1774 	dev->enabled = 1;
1775 
1776 	resource = pci_resource_start(pdev, 0);
1777 	len = pci_resource_len(pdev, 0);
1778 	if (!request_mem_region(resource, len, driver_name)) {
1779 		DBG(dev, "controller already in use\n");
1780 		retval = -EBUSY;
1781 		goto err;
1782 	}
1783 	dev->got_region = 1;
1784 
1785 	base = ioremap(resource, len);
1786 	if (base == NULL) {
1787 		DBG(dev, "can't map memory\n");
1788 		retval = -EFAULT;
1789 		goto err;
1790 	}
1791 	dev->regs = (struct goku_udc_regs __iomem *) base;
1792 
1793 	pci_set_drvdata(pdev, dev);
1794 	INFO(dev, "%s\n", driver_desc);
1795 	INFO(dev, "version: " DRIVER_VERSION " %s\n", dmastr());
1796 	INFO(dev, "irq %d, pci mem %p\n", pdev->irq, base);
1797 
1798 	/* init to known state, then setup irqs */
1799 	udc_reset(dev);
1800 	udc_reinit (dev);
1801 	if (request_irq(pdev->irq, goku_irq, IRQF_SHARED,
1802 			driver_name, dev) != 0) {
1803 		DBG(dev, "request interrupt %d failed\n", pdev->irq);
1804 		retval = -EBUSY;
1805 		goto err;
1806 	}
1807 	dev->got_irq = 1;
1808 	if (use_dma)
1809 		pci_set_master(pdev);
1810 
1811 
1812 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1813 	proc_create_single_data(proc_node_name, 0, NULL, udc_proc_read, dev);
1814 #endif
1815 
1816 	retval = usb_add_gadget_udc_release(&pdev->dev, &dev->gadget,
1817 			gadget_release);
1818 	if (retval)
1819 		goto err;
1820 
1821 	return 0;
1822 
1823 err:
1824 	if (dev)
1825 		goku_remove (pdev);
1826 	/* gadget_release is not registered yet, kfree explicitly */
1827 	kfree(dev);
1828 	return retval;
1829 }
1830 
1831 
1832 /*-------------------------------------------------------------------------*/
1833 
1834 static const struct pci_device_id pci_ids[] = { {
1835 	.class =	PCI_CLASS_SERIAL_USB_DEVICE,
1836 	.class_mask =	~0,
1837 	.vendor =	0x102f,		/* Toshiba */
1838 	.device =	0x0107,		/* this UDC */
1839 	.subvendor =	PCI_ANY_ID,
1840 	.subdevice =	PCI_ANY_ID,
1841 
1842 }, { /* end: all zeroes */ }
1843 };
1844 MODULE_DEVICE_TABLE (pci, pci_ids);
1845 
1846 static struct pci_driver goku_pci_driver = {
1847 	.name =		driver_name,
1848 	.id_table =	pci_ids,
1849 
1850 	.probe =	goku_probe,
1851 	.remove =	goku_remove,
1852 
1853 	/* FIXME add power management support */
1854 };
1855 
1856 module_pci_driver(goku_pci_driver);
1857