1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * drivers/usb/gadget/dwc2_udc_otg.c
4  * Designware DWC2 on-chip full/high speed USB OTG 2.0 device controllers
5  *
6  * Copyright (C) 2008 for Samsung Electronics
7  *
8  * BSP Support for Samsung's UDC driver
9  * available at:
10  * git://git.kernel.org/pub/scm/linux/kernel/git/kki_ap/linux-2.6-samsung.git
11  *
12  * State machine bugfixes:
13  * Marek Szyprowski <m.szyprowski@samsung.com>
14  *
15  * Ported to u-boot:
16  * Marek Szyprowski <m.szyprowski@samsung.com>
17  * Lukasz Majewski <l.majewski@samsumg.com>
18  */
19 #undef DEBUG
20 #include <common.h>
21 #include <linux/errno.h>
22 #include <linux/list.h>
23 #include <malloc.h>
24 
25 #include <linux/usb/ch9.h>
26 #include <linux/usb/gadget.h>
27 
28 #include <asm/byteorder.h>
29 #include <asm/unaligned.h>
30 #include <asm/io.h>
31 
32 #include <asm/mach-types.h>
33 
34 #include "dwc2_udc_otg_regs.h"
35 #include "dwc2_udc_otg_priv.h"
36 #include <usb/lin_gadget_compat.h>
37 
38 /***********************************************************/
39 
40 #define OTG_DMA_MODE		1
41 
42 #define DEBUG_SETUP 0
43 #define DEBUG_EP0 0
44 #define DEBUG_ISR 0
45 #define DEBUG_OUT_EP 0
46 #define DEBUG_IN_EP 0
47 
48 #include <usb/dwc2_udc.h>
49 
50 #define EP0_CON		0
51 #define EP_MASK		0xF
52 
53 static char *state_names[] = {
54 	"WAIT_FOR_SETUP",
55 	"DATA_STATE_XMIT",
56 	"DATA_STATE_NEED_ZLP",
57 	"WAIT_FOR_OUT_STATUS",
58 	"DATA_STATE_RECV",
59 	"WAIT_FOR_COMPLETE",
60 	"WAIT_FOR_OUT_COMPLETE",
61 	"WAIT_FOR_IN_COMPLETE",
62 	"WAIT_FOR_NULL_COMPLETE",
63 };
64 
65 #define DRIVER_VERSION "15 March 2009"
66 
67 struct dwc2_udc	*the_controller;
68 
69 static const char driver_name[] = "dwc2-udc";
70 static const char ep0name[] = "ep0-control";
71 
72 /* Max packet size*/
73 static unsigned int ep0_fifo_size = 64;
74 static unsigned int ep_fifo_size =  512;
75 static unsigned int ep_fifo_size2 = 1024;
76 static int reset_available = 1;
77 
78 static struct usb_ctrlrequest *usb_ctrl;
79 static dma_addr_t usb_ctrl_dma_addr;
80 
81 /*
82   Local declarations.
83 */
84 static int dwc2_ep_enable(struct usb_ep *ep,
85 			 const struct usb_endpoint_descriptor *);
86 static int dwc2_ep_disable(struct usb_ep *ep);
87 static struct usb_request *dwc2_alloc_request(struct usb_ep *ep,
88 					     gfp_t gfp_flags);
89 static void dwc2_free_request(struct usb_ep *ep, struct usb_request *);
90 
91 static int dwc2_queue(struct usb_ep *ep, struct usb_request *, gfp_t gfp_flags);
92 static int dwc2_dequeue(struct usb_ep *ep, struct usb_request *);
93 static int dwc2_fifo_status(struct usb_ep *ep);
94 static void dwc2_fifo_flush(struct usb_ep *ep);
95 static void dwc2_ep0_read(struct dwc2_udc *dev);
96 static void dwc2_ep0_kick(struct dwc2_udc *dev, struct dwc2_ep *ep);
97 static void dwc2_handle_ep0(struct dwc2_udc *dev);
98 static int dwc2_ep0_write(struct dwc2_udc *dev);
99 static int write_fifo_ep0(struct dwc2_ep *ep, struct dwc2_request *req);
100 static void done(struct dwc2_ep *ep, struct dwc2_request *req, int status);
101 static void stop_activity(struct dwc2_udc *dev,
102 			  struct usb_gadget_driver *driver);
103 static int udc_enable(struct dwc2_udc *dev);
104 static void udc_set_address(struct dwc2_udc *dev, unsigned char address);
105 static void reconfig_usbd(struct dwc2_udc *dev);
106 static void set_max_pktsize(struct dwc2_udc *dev, enum usb_device_speed speed);
107 static void nuke(struct dwc2_ep *ep, int status);
108 static int dwc2_udc_set_halt(struct usb_ep *_ep, int value);
109 static void dwc2_udc_set_nak(struct dwc2_ep *ep);
110 
111 void set_udc_gadget_private_data(void *p)
112 {
113 	debug_cond(DEBUG_SETUP != 0,
114 		   "%s: the_controller: 0x%p, p: 0x%p\n", __func__,
115 		   the_controller, p);
116 	the_controller->gadget.dev.device_data = p;
117 }
118 
119 void *get_udc_gadget_private_data(struct usb_gadget *gadget)
120 {
121 	return gadget->dev.device_data;
122 }
123 
124 static struct usb_ep_ops dwc2_ep_ops = {
125 	.enable = dwc2_ep_enable,
126 	.disable = dwc2_ep_disable,
127 
128 	.alloc_request = dwc2_alloc_request,
129 	.free_request = dwc2_free_request,
130 
131 	.queue = dwc2_queue,
132 	.dequeue = dwc2_dequeue,
133 
134 	.set_halt = dwc2_udc_set_halt,
135 	.fifo_status = dwc2_fifo_status,
136 	.fifo_flush = dwc2_fifo_flush,
137 };
138 
139 #define create_proc_files() do {} while (0)
140 #define remove_proc_files() do {} while (0)
141 
142 /***********************************************************/
143 
144 void __iomem		*regs_otg;
145 struct dwc2_usbotg_reg *reg;
146 
147 bool dfu_usb_get_reset(void)
148 {
149 	return !!(readl(&reg->gintsts) & INT_RESET);
150 }
151 
152 __weak void otg_phy_init(struct dwc2_udc *dev) {}
153 __weak void otg_phy_off(struct dwc2_udc *dev) {}
154 
155 /***********************************************************/
156 
157 #include "dwc2_udc_otg_xfer_dma.c"
158 
159 /*
160  *	udc_disable - disable USB device controller
161  */
162 static void udc_disable(struct dwc2_udc *dev)
163 {
164 	debug_cond(DEBUG_SETUP != 0, "%s: %p\n", __func__, dev);
165 
166 	udc_set_address(dev, 0);
167 
168 	dev->ep0state = WAIT_FOR_SETUP;
169 	dev->gadget.speed = USB_SPEED_UNKNOWN;
170 	dev->usb_address = 0;
171 
172 	otg_phy_off(dev);
173 }
174 
175 /*
176  *	udc_reinit - initialize software state
177  */
178 static void udc_reinit(struct dwc2_udc *dev)
179 {
180 	unsigned int i;
181 
182 	debug_cond(DEBUG_SETUP != 0, "%s: %p\n", __func__, dev);
183 
184 	/* device/ep0 records init */
185 	INIT_LIST_HEAD(&dev->gadget.ep_list);
186 	INIT_LIST_HEAD(&dev->gadget.ep0->ep_list);
187 	dev->ep0state = WAIT_FOR_SETUP;
188 
189 	/* basic endpoint records init */
190 	for (i = 0; i < DWC2_MAX_ENDPOINTS; i++) {
191 		struct dwc2_ep *ep = &dev->ep[i];
192 
193 		if (i != 0)
194 			list_add_tail(&ep->ep.ep_list, &dev->gadget.ep_list);
195 
196 		ep->desc = 0;
197 		ep->stopped = 0;
198 		INIT_LIST_HEAD(&ep->queue);
199 		ep->pio_irqs = 0;
200 	}
201 
202 	/* the rest was statically initialized, and is read-only */
203 }
204 
205 #define BYTES2MAXP(x)	(x / 8)
206 #define MAXP2BYTES(x)	(x * 8)
207 
208 /* until it's enabled, this UDC should be completely invisible
209  * to any USB host.
210  */
211 static int udc_enable(struct dwc2_udc *dev)
212 {
213 	debug_cond(DEBUG_SETUP != 0, "%s: %p\n", __func__, dev);
214 
215 	otg_phy_init(dev);
216 	reconfig_usbd(dev);
217 
218 	debug_cond(DEBUG_SETUP != 0,
219 		   "DWC2 USB 2.0 OTG Controller Core Initialized : 0x%x\n",
220 		    readl(&reg->gintmsk));
221 
222 	dev->gadget.speed = USB_SPEED_UNKNOWN;
223 
224 	return 0;
225 }
226 
227 /*
228   Register entry point for the peripheral controller driver.
229 */
230 int usb_gadget_register_driver(struct usb_gadget_driver *driver)
231 {
232 	struct dwc2_udc *dev = the_controller;
233 	int retval = 0;
234 	unsigned long flags = 0;
235 
236 	debug_cond(DEBUG_SETUP != 0, "%s: %s\n", __func__, "no name");
237 
238 	if (!driver
239 	    || (driver->speed != USB_SPEED_FULL
240 		&& driver->speed != USB_SPEED_HIGH)
241 	    || !driver->bind || !driver->disconnect || !driver->setup)
242 		return -EINVAL;
243 	if (!dev)
244 		return -ENODEV;
245 	if (dev->driver)
246 		return -EBUSY;
247 
248 	spin_lock_irqsave(&dev->lock, flags);
249 	/* first hook up the driver ... */
250 	dev->driver = driver;
251 	spin_unlock_irqrestore(&dev->lock, flags);
252 
253 	if (retval) { /* TODO */
254 		printf("target device_add failed, error %d\n", retval);
255 		return retval;
256 	}
257 
258 	retval = driver->bind(&dev->gadget);
259 	if (retval) {
260 		debug_cond(DEBUG_SETUP != 0,
261 			   "%s: bind to driver --> error %d\n",
262 			    dev->gadget.name, retval);
263 		dev->driver = 0;
264 		return retval;
265 	}
266 
267 	enable_irq(IRQ_OTG);
268 
269 	debug_cond(DEBUG_SETUP != 0,
270 		   "Registered gadget driver %s\n", dev->gadget.name);
271 	udc_enable(dev);
272 
273 	return 0;
274 }
275 
276 /*
277  * Unregister entry point for the peripheral controller driver.
278  */
279 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
280 {
281 	struct dwc2_udc *dev = the_controller;
282 	unsigned long flags = 0;
283 
284 	if (!dev)
285 		return -ENODEV;
286 	if (!driver || driver != dev->driver)
287 		return -EINVAL;
288 
289 	spin_lock_irqsave(&dev->lock, flags);
290 	dev->driver = 0;
291 	stop_activity(dev, driver);
292 	spin_unlock_irqrestore(&dev->lock, flags);
293 
294 	driver->unbind(&dev->gadget);
295 
296 	disable_irq(IRQ_OTG);
297 
298 	udc_disable(dev);
299 	return 0;
300 }
301 
302 /*
303  *	done - retire a request; caller blocked irqs
304  */
305 static void done(struct dwc2_ep *ep, struct dwc2_request *req, int status)
306 {
307 	unsigned int stopped = ep->stopped;
308 
309 	debug("%s: %s %p, req = %p, stopped = %d\n",
310 	      __func__, ep->ep.name, ep, &req->req, stopped);
311 
312 	list_del_init(&req->queue);
313 
314 	if (likely(req->req.status == -EINPROGRESS))
315 		req->req.status = status;
316 	else
317 		status = req->req.status;
318 
319 	if (status && status != -ESHUTDOWN) {
320 		debug("complete %s req %p stat %d len %u/%u\n",
321 		      ep->ep.name, &req->req, status,
322 		      req->req.actual, req->req.length);
323 	}
324 
325 	/* don't modify queue heads during completion callback */
326 	ep->stopped = 1;
327 
328 #ifdef DEBUG
329 	printf("calling complete callback\n");
330 	{
331 		int i, len = req->req.length;
332 
333 		printf("pkt[%d] = ", req->req.length);
334 		if (len > 64)
335 			len = 64;
336 		for (i = 0; i < len; i++) {
337 			printf("%02x", ((u8 *)req->req.buf)[i]);
338 			if ((i & 7) == 7)
339 				printf(" ");
340 		}
341 		printf("\n");
342 	}
343 #endif
344 	spin_unlock(&ep->dev->lock);
345 	req->req.complete(&ep->ep, &req->req);
346 	spin_lock(&ep->dev->lock);
347 
348 	debug("callback completed\n");
349 
350 	ep->stopped = stopped;
351 }
352 
353 /*
354  *	nuke - dequeue ALL requests
355  */
356 static void nuke(struct dwc2_ep *ep, int status)
357 {
358 	struct dwc2_request *req;
359 
360 	debug("%s: %s %p\n", __func__, ep->ep.name, ep);
361 
362 	/* called with irqs blocked */
363 	while (!list_empty(&ep->queue)) {
364 		req = list_entry(ep->queue.next, struct dwc2_request, queue);
365 		done(ep, req, status);
366 	}
367 }
368 
369 static void stop_activity(struct dwc2_udc *dev,
370 			  struct usb_gadget_driver *driver)
371 {
372 	int i;
373 
374 	/* don't disconnect drivers more than once */
375 	if (dev->gadget.speed == USB_SPEED_UNKNOWN)
376 		driver = 0;
377 	dev->gadget.speed = USB_SPEED_UNKNOWN;
378 
379 	/* prevent new request submissions, kill any outstanding requests  */
380 	for (i = 0; i < DWC2_MAX_ENDPOINTS; i++) {
381 		struct dwc2_ep *ep = &dev->ep[i];
382 		ep->stopped = 1;
383 		nuke(ep, -ESHUTDOWN);
384 	}
385 
386 	/* report disconnect; the driver is already quiesced */
387 	if (driver) {
388 		spin_unlock(&dev->lock);
389 		driver->disconnect(&dev->gadget);
390 		spin_lock(&dev->lock);
391 	}
392 
393 	/* re-init driver-visible data structures */
394 	udc_reinit(dev);
395 }
396 
397 static void reconfig_usbd(struct dwc2_udc *dev)
398 {
399 	/* 2. Soft-reset OTG Core and then unreset again. */
400 	int i;
401 	unsigned int uTemp = writel(CORE_SOFT_RESET, &reg->grstctl);
402 	uint32_t dflt_gusbcfg;
403 	uint32_t rx_fifo_sz, tx_fifo_sz, np_tx_fifo_sz;
404 
405 	debug("Reseting OTG controller\n");
406 
407 	dflt_gusbcfg =
408 		0<<15		/* PHY Low Power Clock sel*/
409 		|1<<14		/* Non-Periodic TxFIFO Rewind Enable*/
410 		|0x5<<10	/* Turnaround time*/
411 		|0<<9 | 0<<8	/* [0:HNP disable,1:HNP enable][ 0:SRP disable*/
412 				/* 1:SRP enable] H1= 1,1*/
413 		|0<<7		/* Ulpi DDR sel*/
414 		|0<<6		/* 0: high speed utmi+, 1: full speed serial*/
415 		|0<<4		/* 0: utmi+, 1:ulpi*/
416 #ifdef CONFIG_USB_GADGET_DWC2_OTG_PHY_BUS_WIDTH_8
417 		|0<<3		/* phy i/f  0:8bit, 1:16bit*/
418 #else
419 		|1<<3		/* phy i/f  0:8bit, 1:16bit*/
420 #endif
421 		|0x7<<0;	/* HS/FS Timeout**/
422 
423 	if (dev->pdata->usb_gusbcfg)
424 		dflt_gusbcfg = dev->pdata->usb_gusbcfg;
425 
426 	writel(dflt_gusbcfg, &reg->gusbcfg);
427 
428 	/* 3. Put the OTG device core in the disconnected state.*/
429 	uTemp = readl(&reg->dctl);
430 	uTemp |= SOFT_DISCONNECT;
431 	writel(uTemp, &reg->dctl);
432 
433 	udelay(20);
434 
435 	/* 4. Make the OTG device core exit from the disconnected state.*/
436 	uTemp = readl(&reg->dctl);
437 	uTemp = uTemp & ~SOFT_DISCONNECT;
438 	writel(uTemp, &reg->dctl);
439 
440 	/* 5. Configure OTG Core to initial settings of device mode.*/
441 	/* [][1: full speed(30Mhz) 0:high speed]*/
442 	writel(EP_MISS_CNT(1) | DEV_SPEED_HIGH_SPEED_20, &reg->dcfg);
443 
444 	mdelay(1);
445 
446 	/* 6. Unmask the core interrupts*/
447 	writel(GINTMSK_INIT, &reg->gintmsk);
448 
449 	/* 7. Set NAK bit of EP0, EP1, EP2*/
450 	writel(DEPCTL_EPDIS|DEPCTL_SNAK, &reg->out_endp[EP0_CON].doepctl);
451 	writel(DEPCTL_EPDIS|DEPCTL_SNAK, &reg->in_endp[EP0_CON].diepctl);
452 
453 	for (i = 1; i < DWC2_MAX_ENDPOINTS; i++) {
454 		writel(DEPCTL_EPDIS|DEPCTL_SNAK, &reg->out_endp[i].doepctl);
455 		writel(DEPCTL_EPDIS|DEPCTL_SNAK, &reg->in_endp[i].diepctl);
456 	}
457 
458 	/* 8. Unmask EPO interrupts*/
459 	writel(((1 << EP0_CON) << DAINT_OUT_BIT)
460 	       | (1 << EP0_CON), &reg->daintmsk);
461 
462 	/* 9. Unmask device OUT EP common interrupts*/
463 	writel(DOEPMSK_INIT, &reg->doepmsk);
464 
465 	/* 10. Unmask device IN EP common interrupts*/
466 	writel(DIEPMSK_INIT, &reg->diepmsk);
467 
468 	rx_fifo_sz = RX_FIFO_SIZE;
469 	np_tx_fifo_sz = NPTX_FIFO_SIZE;
470 	tx_fifo_sz = PTX_FIFO_SIZE;
471 
472 	if (dev->pdata->rx_fifo_sz)
473 		rx_fifo_sz = dev->pdata->rx_fifo_sz;
474 	if (dev->pdata->np_tx_fifo_sz)
475 		np_tx_fifo_sz = dev->pdata->np_tx_fifo_sz;
476 	if (dev->pdata->tx_fifo_sz)
477 		tx_fifo_sz = dev->pdata->tx_fifo_sz;
478 
479 	/* 11. Set Rx FIFO Size (in 32-bit words) */
480 	writel(rx_fifo_sz, &reg->grxfsiz);
481 
482 	/* 12. Set Non Periodic Tx FIFO Size */
483 	writel((np_tx_fifo_sz << 16) | rx_fifo_sz,
484 	       &reg->gnptxfsiz);
485 
486 	for (i = 1; i < DWC2_MAX_HW_ENDPOINTS; i++)
487 		writel((rx_fifo_sz + np_tx_fifo_sz + tx_fifo_sz*(i-1)) |
488 			tx_fifo_sz << 16, &reg->dieptxf[i-1]);
489 
490 	/* Flush the RX FIFO */
491 	writel(RX_FIFO_FLUSH, &reg->grstctl);
492 	while (readl(&reg->grstctl) & RX_FIFO_FLUSH)
493 		debug("%s: waiting for DWC2_UDC_OTG_GRSTCTL\n", __func__);
494 
495 	/* Flush all the Tx FIFO's */
496 	writel(TX_FIFO_FLUSH_ALL, &reg->grstctl);
497 	writel(TX_FIFO_FLUSH_ALL | TX_FIFO_FLUSH, &reg->grstctl);
498 	while (readl(&reg->grstctl) & TX_FIFO_FLUSH)
499 		debug("%s: waiting for DWC2_UDC_OTG_GRSTCTL\n", __func__);
500 
501 	/* 13. Clear NAK bit of EP0, EP1, EP2*/
502 	/* For Slave mode*/
503 	/* EP0: Control OUT */
504 	writel(DEPCTL_EPDIS | DEPCTL_CNAK,
505 	       &reg->out_endp[EP0_CON].doepctl);
506 
507 	/* 14. Initialize OTG Link Core.*/
508 	writel(GAHBCFG_INIT, &reg->gahbcfg);
509 }
510 
511 static void set_max_pktsize(struct dwc2_udc *dev, enum usb_device_speed speed)
512 {
513 	unsigned int ep_ctrl;
514 	int i;
515 
516 	if (speed == USB_SPEED_HIGH) {
517 		ep0_fifo_size = 64;
518 		ep_fifo_size = 512;
519 		ep_fifo_size2 = 1024;
520 		dev->gadget.speed = USB_SPEED_HIGH;
521 	} else {
522 		ep0_fifo_size = 64;
523 		ep_fifo_size = 64;
524 		ep_fifo_size2 = 64;
525 		dev->gadget.speed = USB_SPEED_FULL;
526 	}
527 
528 	dev->ep[0].ep.maxpacket = ep0_fifo_size;
529 	for (i = 1; i < DWC2_MAX_ENDPOINTS; i++)
530 		dev->ep[i].ep.maxpacket = ep_fifo_size;
531 
532 	/* EP0 - Control IN (64 bytes)*/
533 	ep_ctrl = readl(&reg->in_endp[EP0_CON].diepctl);
534 	writel(ep_ctrl|(0<<0), &reg->in_endp[EP0_CON].diepctl);
535 
536 	/* EP0 - Control OUT (64 bytes)*/
537 	ep_ctrl = readl(&reg->out_endp[EP0_CON].doepctl);
538 	writel(ep_ctrl|(0<<0), &reg->out_endp[EP0_CON].doepctl);
539 }
540 
541 static int dwc2_ep_enable(struct usb_ep *_ep,
542 			 const struct usb_endpoint_descriptor *desc)
543 {
544 	struct dwc2_ep *ep;
545 	struct dwc2_udc *dev;
546 	unsigned long flags = 0;
547 
548 	debug("%s: %p\n", __func__, _ep);
549 
550 	ep = container_of(_ep, struct dwc2_ep, ep);
551 	if (!_ep || !desc || ep->desc || _ep->name == ep0name
552 	    || desc->bDescriptorType != USB_DT_ENDPOINT
553 	    || ep->bEndpointAddress != desc->bEndpointAddress
554 	    || ep_maxpacket(ep) <
555 	    le16_to_cpu(get_unaligned(&desc->wMaxPacketSize))) {
556 
557 		debug("%s: bad ep or descriptor\n", __func__);
558 		return -EINVAL;
559 	}
560 
561 	/* xfer types must match, except that interrupt ~= bulk */
562 	if (ep->bmAttributes != desc->bmAttributes
563 	    && ep->bmAttributes != USB_ENDPOINT_XFER_BULK
564 	    && desc->bmAttributes != USB_ENDPOINT_XFER_INT) {
565 
566 		debug("%s: %s type mismatch\n", __func__, _ep->name);
567 		return -EINVAL;
568 	}
569 
570 	/* hardware _could_ do smaller, but driver doesn't */
571 	if ((desc->bmAttributes == USB_ENDPOINT_XFER_BULK &&
572 	     le16_to_cpu(get_unaligned(&desc->wMaxPacketSize)) >
573 	     ep_maxpacket(ep)) || !get_unaligned(&desc->wMaxPacketSize)) {
574 
575 		debug("%s: bad %s maxpacket\n", __func__, _ep->name);
576 		return -ERANGE;
577 	}
578 
579 	dev = ep->dev;
580 	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) {
581 
582 		debug("%s: bogus device state\n", __func__);
583 		return -ESHUTDOWN;
584 	}
585 
586 	ep->stopped = 0;
587 	ep->desc = desc;
588 	ep->pio_irqs = 0;
589 	ep->ep.maxpacket = le16_to_cpu(get_unaligned(&desc->wMaxPacketSize));
590 
591 	/* Reset halt state */
592 	dwc2_udc_set_nak(ep);
593 	dwc2_udc_set_halt(_ep, 0);
594 
595 	spin_lock_irqsave(&ep->dev->lock, flags);
596 	dwc2_udc_ep_activate(ep);
597 	spin_unlock_irqrestore(&ep->dev->lock, flags);
598 
599 	debug("%s: enabled %s, stopped = %d, maxpacket = %d\n",
600 	      __func__, _ep->name, ep->stopped, ep->ep.maxpacket);
601 	return 0;
602 }
603 
604 /*
605  * Disable EP
606  */
607 static int dwc2_ep_disable(struct usb_ep *_ep)
608 {
609 	struct dwc2_ep *ep;
610 	unsigned long flags = 0;
611 
612 	debug("%s: %p\n", __func__, _ep);
613 
614 	ep = container_of(_ep, struct dwc2_ep, ep);
615 	if (!_ep || !ep->desc) {
616 		debug("%s: %s not enabled\n", __func__,
617 		      _ep ? ep->ep.name : NULL);
618 		return -EINVAL;
619 	}
620 
621 	spin_lock_irqsave(&ep->dev->lock, flags);
622 
623 	/* Nuke all pending requests */
624 	nuke(ep, -ESHUTDOWN);
625 
626 	ep->desc = 0;
627 	ep->stopped = 1;
628 
629 	spin_unlock_irqrestore(&ep->dev->lock, flags);
630 
631 	debug("%s: disabled %s\n", __func__, _ep->name);
632 	return 0;
633 }
634 
635 static struct usb_request *dwc2_alloc_request(struct usb_ep *ep,
636 					     gfp_t gfp_flags)
637 {
638 	struct dwc2_request *req;
639 
640 	debug("%s: %s %p\n", __func__, ep->name, ep);
641 
642 	req = memalign(CONFIG_SYS_CACHELINE_SIZE, sizeof(*req));
643 	if (!req)
644 		return 0;
645 
646 	memset(req, 0, sizeof *req);
647 	INIT_LIST_HEAD(&req->queue);
648 
649 	return &req->req;
650 }
651 
652 static void dwc2_free_request(struct usb_ep *ep, struct usb_request *_req)
653 {
654 	struct dwc2_request *req;
655 
656 	debug("%s: %p\n", __func__, ep);
657 
658 	req = container_of(_req, struct dwc2_request, req);
659 	WARN_ON(!list_empty(&req->queue));
660 	kfree(req);
661 }
662 
663 /* dequeue JUST ONE request */
664 static int dwc2_dequeue(struct usb_ep *_ep, struct usb_request *_req)
665 {
666 	struct dwc2_ep *ep;
667 	struct dwc2_request *req;
668 	unsigned long flags = 0;
669 
670 	debug("%s: %p\n", __func__, _ep);
671 
672 	ep = container_of(_ep, struct dwc2_ep, ep);
673 	if (!_ep || ep->ep.name == ep0name)
674 		return -EINVAL;
675 
676 	spin_lock_irqsave(&ep->dev->lock, flags);
677 
678 	/* make sure it's actually queued on this endpoint */
679 	list_for_each_entry(req, &ep->queue, queue) {
680 		if (&req->req == _req)
681 			break;
682 	}
683 	if (&req->req != _req) {
684 		spin_unlock_irqrestore(&ep->dev->lock, flags);
685 		return -EINVAL;
686 	}
687 
688 	done(ep, req, -ECONNRESET);
689 
690 	spin_unlock_irqrestore(&ep->dev->lock, flags);
691 	return 0;
692 }
693 
694 /*
695  * Return bytes in EP FIFO
696  */
697 static int dwc2_fifo_status(struct usb_ep *_ep)
698 {
699 	int count = 0;
700 	struct dwc2_ep *ep;
701 
702 	ep = container_of(_ep, struct dwc2_ep, ep);
703 	if (!_ep) {
704 		debug("%s: bad ep\n", __func__);
705 		return -ENODEV;
706 	}
707 
708 	debug("%s: %d\n", __func__, ep_index(ep));
709 
710 	/* LPD can't report unclaimed bytes from IN fifos */
711 	if (ep_is_in(ep))
712 		return -EOPNOTSUPP;
713 
714 	return count;
715 }
716 
717 /*
718  * Flush EP FIFO
719  */
720 static void dwc2_fifo_flush(struct usb_ep *_ep)
721 {
722 	struct dwc2_ep *ep;
723 
724 	ep = container_of(_ep, struct dwc2_ep, ep);
725 	if (unlikely(!_ep || (!ep->desc && ep->ep.name != ep0name))) {
726 		debug("%s: bad ep\n", __func__);
727 		return;
728 	}
729 
730 	debug("%s: %d\n", __func__, ep_index(ep));
731 }
732 
733 static const struct usb_gadget_ops dwc2_udc_ops = {
734 	/* current versions must always be self-powered */
735 };
736 
737 static struct dwc2_udc memory = {
738 	.usb_address = 0,
739 	.gadget = {
740 		.ops = &dwc2_udc_ops,
741 		.ep0 = &memory.ep[0].ep,
742 		.name = driver_name,
743 	},
744 
745 	/* control endpoint */
746 	.ep[0] = {
747 		.ep = {
748 			.name = ep0name,
749 			.ops = &dwc2_ep_ops,
750 			.maxpacket = EP0_FIFO_SIZE,
751 		},
752 		.dev = &memory,
753 
754 		.bEndpointAddress = 0,
755 		.bmAttributes = 0,
756 
757 		.ep_type = ep_control,
758 	},
759 
760 	/* first group of endpoints */
761 	.ep[1] = {
762 		.ep = {
763 			.name = "ep1in-bulk",
764 			.ops = &dwc2_ep_ops,
765 			.maxpacket = EP_FIFO_SIZE,
766 		},
767 		.dev = &memory,
768 
769 		.bEndpointAddress = USB_DIR_IN | 1,
770 		.bmAttributes = USB_ENDPOINT_XFER_BULK,
771 
772 		.ep_type = ep_bulk_out,
773 		.fifo_num = 1,
774 	},
775 
776 	.ep[2] = {
777 		.ep = {
778 			.name = "ep2out-bulk",
779 			.ops = &dwc2_ep_ops,
780 			.maxpacket = EP_FIFO_SIZE,
781 		},
782 		.dev = &memory,
783 
784 		.bEndpointAddress = USB_DIR_OUT | 2,
785 		.bmAttributes = USB_ENDPOINT_XFER_BULK,
786 
787 		.ep_type = ep_bulk_in,
788 		.fifo_num = 2,
789 	},
790 
791 	.ep[3] = {
792 		.ep = {
793 			.name = "ep3in-int",
794 			.ops = &dwc2_ep_ops,
795 			.maxpacket = EP_FIFO_SIZE,
796 		},
797 		.dev = &memory,
798 
799 		.bEndpointAddress = USB_DIR_IN | 3,
800 		.bmAttributes = USB_ENDPOINT_XFER_INT,
801 
802 		.ep_type = ep_interrupt,
803 		.fifo_num = 3,
804 	},
805 };
806 
807 /*
808  *	probe - binds to the platform device
809  */
810 
811 int dwc2_udc_probe(struct dwc2_plat_otg_data *pdata)
812 {
813 	struct dwc2_udc *dev = &memory;
814 	int retval = 0;
815 
816 	debug("%s: %p\n", __func__, pdata);
817 
818 	dev->pdata = pdata;
819 
820 	reg = (struct dwc2_usbotg_reg *)pdata->regs_otg;
821 
822 	/* regs_otg = (void *)pdata->regs_otg; */
823 
824 	dev->gadget.is_dualspeed = 1;	/* Hack only*/
825 	dev->gadget.is_otg = 0;
826 	dev->gadget.is_a_peripheral = 0;
827 	dev->gadget.b_hnp_enable = 0;
828 	dev->gadget.a_hnp_support = 0;
829 	dev->gadget.a_alt_hnp_support = 0;
830 
831 	the_controller = dev;
832 
833 	usb_ctrl = memalign(CONFIG_SYS_CACHELINE_SIZE,
834 			    ROUND(sizeof(struct usb_ctrlrequest),
835 				  CONFIG_SYS_CACHELINE_SIZE));
836 	if (!usb_ctrl) {
837 		pr_err("No memory available for UDC!\n");
838 		return -ENOMEM;
839 	}
840 
841 	usb_ctrl_dma_addr = (dma_addr_t) usb_ctrl;
842 
843 	udc_reinit(dev);
844 
845 	return retval;
846 }
847 
848 int usb_gadget_handle_interrupts(int index)
849 {
850 	u32 intr_status = readl(&reg->gintsts);
851 	u32 gintmsk = readl(&reg->gintmsk);
852 
853 	if (intr_status & gintmsk)
854 		return dwc2_udc_irq(1, (void *)the_controller);
855 	return 0;
856 }
857