xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision 293d5b43)
1 /*
2  * udc.c - ChipIdea UDC driver
3  *
4  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
5  *
6  * Author: David Lopo
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/dmapool.h>
16 #include <linux/err.h>
17 #include <linux/irqreturn.h>
18 #include <linux/kernel.h>
19 #include <linux/slab.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/usb/ch9.h>
22 #include <linux/usb/gadget.h>
23 #include <linux/usb/otg-fsm.h>
24 #include <linux/usb/chipidea.h>
25 
26 #include "ci.h"
27 #include "udc.h"
28 #include "bits.h"
29 #include "otg.h"
30 #include "otg_fsm.h"
31 
32 /* control endpoint description */
33 static const struct usb_endpoint_descriptor
34 ctrl_endpt_out_desc = {
35 	.bLength         = USB_DT_ENDPOINT_SIZE,
36 	.bDescriptorType = USB_DT_ENDPOINT,
37 
38 	.bEndpointAddress = USB_DIR_OUT,
39 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
40 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
41 };
42 
43 static const struct usb_endpoint_descriptor
44 ctrl_endpt_in_desc = {
45 	.bLength         = USB_DT_ENDPOINT_SIZE,
46 	.bDescriptorType = USB_DT_ENDPOINT,
47 
48 	.bEndpointAddress = USB_DIR_IN,
49 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
50 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
51 };
52 
53 /**
54  * hw_ep_bit: calculates the bit number
55  * @num: endpoint number
56  * @dir: endpoint direction
57  *
58  * This function returns bit number
59  */
60 static inline int hw_ep_bit(int num, int dir)
61 {
62 	return num + (dir ? 16 : 0);
63 }
64 
65 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
66 {
67 	int fill = 16 - ci->hw_ep_max / 2;
68 
69 	if (n >= ci->hw_ep_max / 2)
70 		n += fill;
71 
72 	return n;
73 }
74 
75 /**
76  * hw_device_state: enables/disables interrupts (execute without interruption)
77  * @dma: 0 => disable, !0 => enable and set dma engine
78  *
79  * This function returns an error code
80  */
81 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
82 {
83 	if (dma) {
84 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
85 		/* interrupt, error, port change, reset, sleep/suspend */
86 		hw_write(ci, OP_USBINTR, ~0,
87 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
88 	} else {
89 		hw_write(ci, OP_USBINTR, ~0, 0);
90 	}
91 	return 0;
92 }
93 
94 /**
95  * hw_ep_flush: flush endpoint fifo (execute without interruption)
96  * @num: endpoint number
97  * @dir: endpoint direction
98  *
99  * This function returns an error code
100  */
101 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
102 {
103 	int n = hw_ep_bit(num, dir);
104 
105 	do {
106 		/* flush any pending transfer */
107 		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
108 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
109 			cpu_relax();
110 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
111 
112 	return 0;
113 }
114 
115 /**
116  * hw_ep_disable: disables endpoint (execute without interruption)
117  * @num: endpoint number
118  * @dir: endpoint direction
119  *
120  * This function returns an error code
121  */
122 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
123 {
124 	hw_ep_flush(ci, num, dir);
125 	hw_write(ci, OP_ENDPTCTRL + num,
126 		 dir ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
127 	return 0;
128 }
129 
130 /**
131  * hw_ep_enable: enables endpoint (execute without interruption)
132  * @num:  endpoint number
133  * @dir:  endpoint direction
134  * @type: endpoint type
135  *
136  * This function returns an error code
137  */
138 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
139 {
140 	u32 mask, data;
141 
142 	if (dir) {
143 		mask  = ENDPTCTRL_TXT;  /* type    */
144 		data  = type << __ffs(mask);
145 
146 		mask |= ENDPTCTRL_TXS;  /* unstall */
147 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
148 		data |= ENDPTCTRL_TXR;
149 		mask |= ENDPTCTRL_TXE;  /* enable  */
150 		data |= ENDPTCTRL_TXE;
151 	} else {
152 		mask  = ENDPTCTRL_RXT;  /* type    */
153 		data  = type << __ffs(mask);
154 
155 		mask |= ENDPTCTRL_RXS;  /* unstall */
156 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
157 		data |= ENDPTCTRL_RXR;
158 		mask |= ENDPTCTRL_RXE;  /* enable  */
159 		data |= ENDPTCTRL_RXE;
160 	}
161 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
162 	return 0;
163 }
164 
165 /**
166  * hw_ep_get_halt: return endpoint halt status
167  * @num: endpoint number
168  * @dir: endpoint direction
169  *
170  * This function returns 1 if endpoint halted
171  */
172 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
173 {
174 	u32 mask = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
175 
176 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
177 }
178 
179 /**
180  * hw_ep_prime: primes endpoint (execute without interruption)
181  * @num:     endpoint number
182  * @dir:     endpoint direction
183  * @is_ctrl: true if control endpoint
184  *
185  * This function returns an error code
186  */
187 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
188 {
189 	int n = hw_ep_bit(num, dir);
190 
191 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
192 		return -EAGAIN;
193 
194 	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
195 
196 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
197 		cpu_relax();
198 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
199 		return -EAGAIN;
200 
201 	/* status shoult be tested according with manual but it doesn't work */
202 	return 0;
203 }
204 
205 /**
206  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
207  *                 without interruption)
208  * @num:   endpoint number
209  * @dir:   endpoint direction
210  * @value: true => stall, false => unstall
211  *
212  * This function returns an error code
213  */
214 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
215 {
216 	if (value != 0 && value != 1)
217 		return -EINVAL;
218 
219 	do {
220 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
221 		u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
222 		u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
223 
224 		/* data toggle - reserved for EP0 but it's in ESS */
225 		hw_write(ci, reg, mask_xs|mask_xr,
226 			  value ? mask_xs : mask_xr);
227 	} while (value != hw_ep_get_halt(ci, num, dir));
228 
229 	return 0;
230 }
231 
232 /**
233  * hw_is_port_high_speed: test if port is high speed
234  *
235  * This function returns true if high speed port
236  */
237 static int hw_port_is_high_speed(struct ci_hdrc *ci)
238 {
239 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
240 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
241 }
242 
243 /**
244  * hw_test_and_clear_complete: test & clear complete status (execute without
245  *                             interruption)
246  * @n: endpoint number
247  *
248  * This function returns complete status
249  */
250 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
251 {
252 	n = ep_to_bit(ci, n);
253 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
254 }
255 
256 /**
257  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
258  *                                without interruption)
259  *
260  * This function returns active interrutps
261  */
262 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
263 {
264 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
265 
266 	hw_write(ci, OP_USBSTS, ~0, reg);
267 	return reg;
268 }
269 
270 /**
271  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
272  *                                interruption)
273  *
274  * This function returns guard value
275  */
276 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
277 {
278 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
279 }
280 
281 /**
282  * hw_test_and_set_setup_guard: test & set setup guard (execute without
283  *                              interruption)
284  *
285  * This function returns guard value
286  */
287 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
288 {
289 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
290 }
291 
292 /**
293  * hw_usb_set_address: configures USB address (execute without interruption)
294  * @value: new USB address
295  *
296  * This function explicitly sets the address, without the "USBADRA" (advance)
297  * feature, which is not supported by older versions of the controller.
298  */
299 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
300 {
301 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
302 		 value << __ffs(DEVICEADDR_USBADR));
303 }
304 
305 /**
306  * hw_usb_reset: restart device after a bus reset (execute without
307  *               interruption)
308  *
309  * This function returns an error code
310  */
311 static int hw_usb_reset(struct ci_hdrc *ci)
312 {
313 	hw_usb_set_address(ci, 0);
314 
315 	/* ESS flushes only at end?!? */
316 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
317 
318 	/* clear setup token semaphores */
319 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
320 
321 	/* clear complete status */
322 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
323 
324 	/* wait until all bits cleared */
325 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
326 		udelay(10);             /* not RTOS friendly */
327 
328 	/* reset all endpoints ? */
329 
330 	/* reset internal status and wait for further instructions
331 	   no need to verify the port reset status (ESS does it) */
332 
333 	return 0;
334 }
335 
336 /******************************************************************************
337  * UTIL block
338  *****************************************************************************/
339 
340 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
341 			  unsigned length)
342 {
343 	int i;
344 	u32 temp;
345 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
346 						  GFP_ATOMIC);
347 
348 	if (node == NULL)
349 		return -ENOMEM;
350 
351 	node->ptr = dma_pool_zalloc(hwep->td_pool, GFP_ATOMIC,
352 				   &node->dma);
353 	if (node->ptr == NULL) {
354 		kfree(node);
355 		return -ENOMEM;
356 	}
357 
358 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
359 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
360 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
361 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
362 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
363 
364 		if (hwreq->req.length == 0
365 				|| hwreq->req.length % hwep->ep.maxpacket)
366 			mul++;
367 		node->ptr->token |= mul << __ffs(TD_MULTO);
368 	}
369 
370 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
371 	if (length) {
372 		node->ptr->page[0] = cpu_to_le32(temp);
373 		for (i = 1; i < TD_PAGE_COUNT; i++) {
374 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
375 			page &= ~TD_RESERVED_MASK;
376 			node->ptr->page[i] = cpu_to_le32(page);
377 		}
378 	}
379 
380 	hwreq->req.actual += length;
381 
382 	if (!list_empty(&hwreq->tds)) {
383 		/* get the last entry */
384 		lastnode = list_entry(hwreq->tds.prev,
385 				struct td_node, td);
386 		lastnode->ptr->next = cpu_to_le32(node->dma);
387 	}
388 
389 	INIT_LIST_HEAD(&node->td);
390 	list_add_tail(&node->td, &hwreq->tds);
391 
392 	return 0;
393 }
394 
395 /**
396  * _usb_addr: calculates endpoint address from direction & number
397  * @ep:  endpoint
398  */
399 static inline u8 _usb_addr(struct ci_hw_ep *ep)
400 {
401 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
402 }
403 
404 /**
405  * _hardware_enqueue: configures a request at hardware level
406  * @hwep:   endpoint
407  * @hwreq:  request
408  *
409  * This function returns an error code
410  */
411 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
412 {
413 	struct ci_hdrc *ci = hwep->ci;
414 	int ret = 0;
415 	unsigned rest = hwreq->req.length;
416 	int pages = TD_PAGE_COUNT;
417 	struct td_node *firstnode, *lastnode;
418 
419 	/* don't queue twice */
420 	if (hwreq->req.status == -EALREADY)
421 		return -EALREADY;
422 
423 	hwreq->req.status = -EALREADY;
424 
425 	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
426 	if (ret)
427 		return ret;
428 
429 	/*
430 	 * The first buffer could be not page aligned.
431 	 * In that case we have to span into one extra td.
432 	 */
433 	if (hwreq->req.dma % PAGE_SIZE)
434 		pages--;
435 
436 	if (rest == 0) {
437 		ret = add_td_to_list(hwep, hwreq, 0);
438 		if (ret < 0)
439 			goto done;
440 	}
441 
442 	while (rest > 0) {
443 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
444 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
445 		ret = add_td_to_list(hwep, hwreq, count);
446 		if (ret < 0)
447 			goto done;
448 
449 		rest -= count;
450 	}
451 
452 	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
453 	    && (hwreq->req.length % hwep->ep.maxpacket == 0)) {
454 		ret = add_td_to_list(hwep, hwreq, 0);
455 		if (ret < 0)
456 			goto done;
457 	}
458 
459 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
460 
461 	lastnode = list_entry(hwreq->tds.prev,
462 		struct td_node, td);
463 
464 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
465 	if (!hwreq->req.no_interrupt)
466 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
467 	wmb();
468 
469 	hwreq->req.actual = 0;
470 	if (!list_empty(&hwep->qh.queue)) {
471 		struct ci_hw_req *hwreqprev;
472 		int n = hw_ep_bit(hwep->num, hwep->dir);
473 		int tmp_stat;
474 		struct td_node *prevlastnode;
475 		u32 next = firstnode->dma & TD_ADDR_MASK;
476 
477 		hwreqprev = list_entry(hwep->qh.queue.prev,
478 				struct ci_hw_req, queue);
479 		prevlastnode = list_entry(hwreqprev->tds.prev,
480 				struct td_node, td);
481 
482 		prevlastnode->ptr->next = cpu_to_le32(next);
483 		wmb();
484 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
485 			goto done;
486 		do {
487 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
488 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
489 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
490 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
491 		if (tmp_stat)
492 			goto done;
493 	}
494 
495 	/*  QH configuration */
496 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
497 	hwep->qh.ptr->td.token &=
498 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
499 
500 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
501 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
502 
503 		if (hwreq->req.length == 0
504 				|| hwreq->req.length % hwep->ep.maxpacket)
505 			mul++;
506 		hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
507 	}
508 
509 	wmb();   /* synchronize before ep prime */
510 
511 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
512 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
513 done:
514 	return ret;
515 }
516 
517 /*
518  * free_pending_td: remove a pending request for the endpoint
519  * @hwep: endpoint
520  */
521 static void free_pending_td(struct ci_hw_ep *hwep)
522 {
523 	struct td_node *pending = hwep->pending_td;
524 
525 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
526 	hwep->pending_td = NULL;
527 	kfree(pending);
528 }
529 
530 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
531 					   struct td_node *node)
532 {
533 	hwep->qh.ptr->td.next = node->dma;
534 	hwep->qh.ptr->td.token &=
535 		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
536 
537 	/* Synchronize before ep prime */
538 	wmb();
539 
540 	return hw_ep_prime(ci, hwep->num, hwep->dir,
541 				hwep->type == USB_ENDPOINT_XFER_CONTROL);
542 }
543 
544 /**
545  * _hardware_dequeue: handles a request at hardware level
546  * @gadget: gadget
547  * @hwep:   endpoint
548  *
549  * This function returns an error code
550  */
551 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
552 {
553 	u32 tmptoken;
554 	struct td_node *node, *tmpnode;
555 	unsigned remaining_length;
556 	unsigned actual = hwreq->req.length;
557 	struct ci_hdrc *ci = hwep->ci;
558 
559 	if (hwreq->req.status != -EALREADY)
560 		return -EINVAL;
561 
562 	hwreq->req.status = 0;
563 
564 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
565 		tmptoken = le32_to_cpu(node->ptr->token);
566 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
567 			int n = hw_ep_bit(hwep->num, hwep->dir);
568 
569 			if (ci->rev == CI_REVISION_24)
570 				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
571 					reprime_dtd(ci, hwep, node);
572 			hwreq->req.status = -EALREADY;
573 			return -EBUSY;
574 		}
575 
576 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
577 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
578 		actual -= remaining_length;
579 
580 		hwreq->req.status = tmptoken & TD_STATUS;
581 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
582 			hwreq->req.status = -EPIPE;
583 			break;
584 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
585 			hwreq->req.status = -EPROTO;
586 			break;
587 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
588 			hwreq->req.status = -EILSEQ;
589 			break;
590 		}
591 
592 		if (remaining_length) {
593 			if (hwep->dir) {
594 				hwreq->req.status = -EPROTO;
595 				break;
596 			}
597 		}
598 		/*
599 		 * As the hardware could still address the freed td
600 		 * which will run the udc unusable, the cleanup of the
601 		 * td has to be delayed by one.
602 		 */
603 		if (hwep->pending_td)
604 			free_pending_td(hwep);
605 
606 		hwep->pending_td = node;
607 		list_del_init(&node->td);
608 	}
609 
610 	usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
611 
612 	hwreq->req.actual += actual;
613 
614 	if (hwreq->req.status)
615 		return hwreq->req.status;
616 
617 	return hwreq->req.actual;
618 }
619 
620 /**
621  * _ep_nuke: dequeues all endpoint requests
622  * @hwep: endpoint
623  *
624  * This function returns an error code
625  * Caller must hold lock
626  */
627 static int _ep_nuke(struct ci_hw_ep *hwep)
628 __releases(hwep->lock)
629 __acquires(hwep->lock)
630 {
631 	struct td_node *node, *tmpnode;
632 	if (hwep == NULL)
633 		return -EINVAL;
634 
635 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
636 
637 	while (!list_empty(&hwep->qh.queue)) {
638 
639 		/* pop oldest request */
640 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
641 						     struct ci_hw_req, queue);
642 
643 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
644 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
645 			list_del_init(&node->td);
646 			node->ptr = NULL;
647 			kfree(node);
648 		}
649 
650 		list_del_init(&hwreq->queue);
651 		hwreq->req.status = -ESHUTDOWN;
652 
653 		if (hwreq->req.complete != NULL) {
654 			spin_unlock(hwep->lock);
655 			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
656 			spin_lock(hwep->lock);
657 		}
658 	}
659 
660 	if (hwep->pending_td)
661 		free_pending_td(hwep);
662 
663 	return 0;
664 }
665 
666 static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
667 {
668 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
669 	int direction, retval = 0;
670 	unsigned long flags;
671 
672 	if (ep == NULL || hwep->ep.desc == NULL)
673 		return -EINVAL;
674 
675 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
676 		return -EOPNOTSUPP;
677 
678 	spin_lock_irqsave(hwep->lock, flags);
679 
680 	if (value && hwep->dir == TX && check_transfer &&
681 		!list_empty(&hwep->qh.queue) &&
682 			!usb_endpoint_xfer_control(hwep->ep.desc)) {
683 		spin_unlock_irqrestore(hwep->lock, flags);
684 		return -EAGAIN;
685 	}
686 
687 	direction = hwep->dir;
688 	do {
689 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
690 
691 		if (!value)
692 			hwep->wedge = 0;
693 
694 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
695 			hwep->dir = (hwep->dir == TX) ? RX : TX;
696 
697 	} while (hwep->dir != direction);
698 
699 	spin_unlock_irqrestore(hwep->lock, flags);
700 	return retval;
701 }
702 
703 
704 /**
705  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
706  * @gadget: gadget
707  *
708  * This function returns an error code
709  */
710 static int _gadget_stop_activity(struct usb_gadget *gadget)
711 {
712 	struct usb_ep *ep;
713 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
714 	unsigned long flags;
715 
716 	spin_lock_irqsave(&ci->lock, flags);
717 	ci->gadget.speed = USB_SPEED_UNKNOWN;
718 	ci->remote_wakeup = 0;
719 	ci->suspended = 0;
720 	spin_unlock_irqrestore(&ci->lock, flags);
721 
722 	/* flush all endpoints */
723 	gadget_for_each_ep(ep, gadget) {
724 		usb_ep_fifo_flush(ep);
725 	}
726 	usb_ep_fifo_flush(&ci->ep0out->ep);
727 	usb_ep_fifo_flush(&ci->ep0in->ep);
728 
729 	/* make sure to disable all endpoints */
730 	gadget_for_each_ep(ep, gadget) {
731 		usb_ep_disable(ep);
732 	}
733 
734 	if (ci->status != NULL) {
735 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
736 		ci->status = NULL;
737 	}
738 
739 	return 0;
740 }
741 
742 /******************************************************************************
743  * ISR block
744  *****************************************************************************/
745 /**
746  * isr_reset_handler: USB reset interrupt handler
747  * @ci: UDC device
748  *
749  * This function resets USB engine after a bus reset occurred
750  */
751 static void isr_reset_handler(struct ci_hdrc *ci)
752 __releases(ci->lock)
753 __acquires(ci->lock)
754 {
755 	int retval;
756 
757 	spin_unlock(&ci->lock);
758 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
759 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
760 
761 	retval = _gadget_stop_activity(&ci->gadget);
762 	if (retval)
763 		goto done;
764 
765 	retval = hw_usb_reset(ci);
766 	if (retval)
767 		goto done;
768 
769 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
770 	if (ci->status == NULL)
771 		retval = -ENOMEM;
772 
773 done:
774 	spin_lock(&ci->lock);
775 
776 	if (retval)
777 		dev_err(ci->dev, "error: %i\n", retval);
778 }
779 
780 /**
781  * isr_get_status_complete: get_status request complete function
782  * @ep:  endpoint
783  * @req: request handled
784  *
785  * Caller must release lock
786  */
787 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
788 {
789 	if (ep == NULL || req == NULL)
790 		return;
791 
792 	kfree(req->buf);
793 	usb_ep_free_request(ep, req);
794 }
795 
796 /**
797  * _ep_queue: queues (submits) an I/O request to an endpoint
798  * @ep:        endpoint
799  * @req:       request
800  * @gfp_flags: GFP flags (not used)
801  *
802  * Caller must hold lock
803  * This function returns an error code
804  */
805 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
806 		    gfp_t __maybe_unused gfp_flags)
807 {
808 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
809 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
810 	struct ci_hdrc *ci = hwep->ci;
811 	int retval = 0;
812 
813 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
814 		return -EINVAL;
815 
816 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
817 		if (req->length)
818 			hwep = (ci->ep0_dir == RX) ?
819 			       ci->ep0out : ci->ep0in;
820 		if (!list_empty(&hwep->qh.queue)) {
821 			_ep_nuke(hwep);
822 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
823 				 _usb_addr(hwep));
824 		}
825 	}
826 
827 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
828 	    hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
829 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
830 		return -EMSGSIZE;
831 	}
832 
833 	/* first nuke then test link, e.g. previous status has not sent */
834 	if (!list_empty(&hwreq->queue)) {
835 		dev_err(hwep->ci->dev, "request already in queue\n");
836 		return -EBUSY;
837 	}
838 
839 	/* push request */
840 	hwreq->req.status = -EINPROGRESS;
841 	hwreq->req.actual = 0;
842 
843 	retval = _hardware_enqueue(hwep, hwreq);
844 
845 	if (retval == -EALREADY)
846 		retval = 0;
847 	if (!retval)
848 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
849 
850 	return retval;
851 }
852 
853 /**
854  * isr_get_status_response: get_status request response
855  * @ci: ci struct
856  * @setup: setup request packet
857  *
858  * This function returns an error code
859  */
860 static int isr_get_status_response(struct ci_hdrc *ci,
861 				   struct usb_ctrlrequest *setup)
862 __releases(hwep->lock)
863 __acquires(hwep->lock)
864 {
865 	struct ci_hw_ep *hwep = ci->ep0in;
866 	struct usb_request *req = NULL;
867 	gfp_t gfp_flags = GFP_ATOMIC;
868 	int dir, num, retval;
869 
870 	if (hwep == NULL || setup == NULL)
871 		return -EINVAL;
872 
873 	spin_unlock(hwep->lock);
874 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
875 	spin_lock(hwep->lock);
876 	if (req == NULL)
877 		return -ENOMEM;
878 
879 	req->complete = isr_get_status_complete;
880 	req->length   = 2;
881 	req->buf      = kzalloc(req->length, gfp_flags);
882 	if (req->buf == NULL) {
883 		retval = -ENOMEM;
884 		goto err_free_req;
885 	}
886 
887 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
888 		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
889 			ci->gadget.is_selfpowered;
890 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
891 		   == USB_RECIP_ENDPOINT) {
892 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
893 			TX : RX;
894 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
895 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
896 	}
897 	/* else do nothing; reserved for future use */
898 
899 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
900 	if (retval)
901 		goto err_free_buf;
902 
903 	return 0;
904 
905  err_free_buf:
906 	kfree(req->buf);
907  err_free_req:
908 	spin_unlock(hwep->lock);
909 	usb_ep_free_request(&hwep->ep, req);
910 	spin_lock(hwep->lock);
911 	return retval;
912 }
913 
914 /**
915  * isr_setup_status_complete: setup_status request complete function
916  * @ep:  endpoint
917  * @req: request handled
918  *
919  * Caller must release lock. Put the port in test mode if test mode
920  * feature is selected.
921  */
922 static void
923 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
924 {
925 	struct ci_hdrc *ci = req->context;
926 	unsigned long flags;
927 
928 	if (ci->setaddr) {
929 		hw_usb_set_address(ci, ci->address);
930 		ci->setaddr = false;
931 		if (ci->address)
932 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
933 	}
934 
935 	spin_lock_irqsave(&ci->lock, flags);
936 	if (ci->test_mode)
937 		hw_port_test_set(ci, ci->test_mode);
938 	spin_unlock_irqrestore(&ci->lock, flags);
939 }
940 
941 /**
942  * isr_setup_status_phase: queues the status phase of a setup transation
943  * @ci: ci struct
944  *
945  * This function returns an error code
946  */
947 static int isr_setup_status_phase(struct ci_hdrc *ci)
948 {
949 	int retval;
950 	struct ci_hw_ep *hwep;
951 
952 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
953 	ci->status->context = ci;
954 	ci->status->complete = isr_setup_status_complete;
955 
956 	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
957 
958 	return retval;
959 }
960 
961 /**
962  * isr_tr_complete_low: transaction complete low level handler
963  * @hwep: endpoint
964  *
965  * This function returns an error code
966  * Caller must hold lock
967  */
968 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
969 __releases(hwep->lock)
970 __acquires(hwep->lock)
971 {
972 	struct ci_hw_req *hwreq, *hwreqtemp;
973 	struct ci_hw_ep *hweptemp = hwep;
974 	int retval = 0;
975 
976 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
977 			queue) {
978 		retval = _hardware_dequeue(hwep, hwreq);
979 		if (retval < 0)
980 			break;
981 		list_del_init(&hwreq->queue);
982 		if (hwreq->req.complete != NULL) {
983 			spin_unlock(hwep->lock);
984 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
985 					hwreq->req.length)
986 				hweptemp = hwep->ci->ep0in;
987 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
988 			spin_lock(hwep->lock);
989 		}
990 	}
991 
992 	if (retval == -EBUSY)
993 		retval = 0;
994 
995 	return retval;
996 }
997 
998 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
999 {
1000 	dev_warn(&ci->gadget.dev,
1001 		"connect the device to an alternate port if you want HNP\n");
1002 	return isr_setup_status_phase(ci);
1003 }
1004 
1005 /**
1006  * isr_setup_packet_handler: setup packet handler
1007  * @ci: UDC descriptor
1008  *
1009  * This function handles setup packet
1010  */
1011 static void isr_setup_packet_handler(struct ci_hdrc *ci)
1012 __releases(ci->lock)
1013 __acquires(ci->lock)
1014 {
1015 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1016 	struct usb_ctrlrequest req;
1017 	int type, num, dir, err = -EINVAL;
1018 	u8 tmode = 0;
1019 
1020 	/*
1021 	 * Flush data and handshake transactions of previous
1022 	 * setup packet.
1023 	 */
1024 	_ep_nuke(ci->ep0out);
1025 	_ep_nuke(ci->ep0in);
1026 
1027 	/* read_setup_packet */
1028 	do {
1029 		hw_test_and_set_setup_guard(ci);
1030 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1031 	} while (!hw_test_and_clear_setup_guard(ci));
1032 
1033 	type = req.bRequestType;
1034 
1035 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1036 
1037 	switch (req.bRequest) {
1038 	case USB_REQ_CLEAR_FEATURE:
1039 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1040 				le16_to_cpu(req.wValue) ==
1041 				USB_ENDPOINT_HALT) {
1042 			if (req.wLength != 0)
1043 				break;
1044 			num  = le16_to_cpu(req.wIndex);
1045 			dir = num & USB_ENDPOINT_DIR_MASK;
1046 			num &= USB_ENDPOINT_NUMBER_MASK;
1047 			if (dir) /* TX */
1048 				num += ci->hw_ep_max / 2;
1049 			if (!ci->ci_hw_ep[num].wedge) {
1050 				spin_unlock(&ci->lock);
1051 				err = usb_ep_clear_halt(
1052 					&ci->ci_hw_ep[num].ep);
1053 				spin_lock(&ci->lock);
1054 				if (err)
1055 					break;
1056 			}
1057 			err = isr_setup_status_phase(ci);
1058 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1059 				le16_to_cpu(req.wValue) ==
1060 				USB_DEVICE_REMOTE_WAKEUP) {
1061 			if (req.wLength != 0)
1062 				break;
1063 			ci->remote_wakeup = 0;
1064 			err = isr_setup_status_phase(ci);
1065 		} else {
1066 			goto delegate;
1067 		}
1068 		break;
1069 	case USB_REQ_GET_STATUS:
1070 		if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
1071 			le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
1072 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1073 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1074 			goto delegate;
1075 		if (le16_to_cpu(req.wLength) != 2 ||
1076 		    le16_to_cpu(req.wValue)  != 0)
1077 			break;
1078 		err = isr_get_status_response(ci, &req);
1079 		break;
1080 	case USB_REQ_SET_ADDRESS:
1081 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1082 			goto delegate;
1083 		if (le16_to_cpu(req.wLength) != 0 ||
1084 		    le16_to_cpu(req.wIndex)  != 0)
1085 			break;
1086 		ci->address = (u8)le16_to_cpu(req.wValue);
1087 		ci->setaddr = true;
1088 		err = isr_setup_status_phase(ci);
1089 		break;
1090 	case USB_REQ_SET_FEATURE:
1091 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1092 				le16_to_cpu(req.wValue) ==
1093 				USB_ENDPOINT_HALT) {
1094 			if (req.wLength != 0)
1095 				break;
1096 			num  = le16_to_cpu(req.wIndex);
1097 			dir = num & USB_ENDPOINT_DIR_MASK;
1098 			num &= USB_ENDPOINT_NUMBER_MASK;
1099 			if (dir) /* TX */
1100 				num += ci->hw_ep_max / 2;
1101 
1102 			spin_unlock(&ci->lock);
1103 			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1104 			spin_lock(&ci->lock);
1105 			if (!err)
1106 				isr_setup_status_phase(ci);
1107 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1108 			if (req.wLength != 0)
1109 				break;
1110 			switch (le16_to_cpu(req.wValue)) {
1111 			case USB_DEVICE_REMOTE_WAKEUP:
1112 				ci->remote_wakeup = 1;
1113 				err = isr_setup_status_phase(ci);
1114 				break;
1115 			case USB_DEVICE_TEST_MODE:
1116 				tmode = le16_to_cpu(req.wIndex) >> 8;
1117 				switch (tmode) {
1118 				case TEST_J:
1119 				case TEST_K:
1120 				case TEST_SE0_NAK:
1121 				case TEST_PACKET:
1122 				case TEST_FORCE_EN:
1123 					ci->test_mode = tmode;
1124 					err = isr_setup_status_phase(
1125 							ci);
1126 					break;
1127 				default:
1128 					break;
1129 				}
1130 				break;
1131 			case USB_DEVICE_B_HNP_ENABLE:
1132 				if (ci_otg_is_fsm_mode(ci)) {
1133 					ci->gadget.b_hnp_enable = 1;
1134 					err = isr_setup_status_phase(
1135 							ci);
1136 				}
1137 				break;
1138 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1139 				if (ci_otg_is_fsm_mode(ci))
1140 					err = otg_a_alt_hnp_support(ci);
1141 				break;
1142 			case USB_DEVICE_A_HNP_SUPPORT:
1143 				if (ci_otg_is_fsm_mode(ci)) {
1144 					ci->gadget.a_hnp_support = 1;
1145 					err = isr_setup_status_phase(
1146 							ci);
1147 				}
1148 				break;
1149 			default:
1150 				goto delegate;
1151 			}
1152 		} else {
1153 			goto delegate;
1154 		}
1155 		break;
1156 	default:
1157 delegate:
1158 		if (req.wLength == 0)   /* no data phase */
1159 			ci->ep0_dir = TX;
1160 
1161 		spin_unlock(&ci->lock);
1162 		err = ci->driver->setup(&ci->gadget, &req);
1163 		spin_lock(&ci->lock);
1164 		break;
1165 	}
1166 
1167 	if (err < 0) {
1168 		spin_unlock(&ci->lock);
1169 		if (_ep_set_halt(&hwep->ep, 1, false))
1170 			dev_err(ci->dev, "error: _ep_set_halt\n");
1171 		spin_lock(&ci->lock);
1172 	}
1173 }
1174 
1175 /**
1176  * isr_tr_complete_handler: transaction complete interrupt handler
1177  * @ci: UDC descriptor
1178  *
1179  * This function handles traffic events
1180  */
1181 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1182 __releases(ci->lock)
1183 __acquires(ci->lock)
1184 {
1185 	unsigned i;
1186 	int err;
1187 
1188 	for (i = 0; i < ci->hw_ep_max; i++) {
1189 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1190 
1191 		if (hwep->ep.desc == NULL)
1192 			continue;   /* not configured */
1193 
1194 		if (hw_test_and_clear_complete(ci, i)) {
1195 			err = isr_tr_complete_low(hwep);
1196 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1197 				if (err > 0)   /* needs status phase */
1198 					err = isr_setup_status_phase(ci);
1199 				if (err < 0) {
1200 					spin_unlock(&ci->lock);
1201 					if (_ep_set_halt(&hwep->ep, 1, false))
1202 						dev_err(ci->dev,
1203 						"error: _ep_set_halt\n");
1204 					spin_lock(&ci->lock);
1205 				}
1206 			}
1207 		}
1208 
1209 		/* Only handle setup packet below */
1210 		if (i == 0 &&
1211 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1212 			isr_setup_packet_handler(ci);
1213 	}
1214 }
1215 
1216 /******************************************************************************
1217  * ENDPT block
1218  *****************************************************************************/
1219 /**
1220  * ep_enable: configure endpoint, making it usable
1221  *
1222  * Check usb_ep_enable() at "usb_gadget.h" for details
1223  */
1224 static int ep_enable(struct usb_ep *ep,
1225 		     const struct usb_endpoint_descriptor *desc)
1226 {
1227 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1228 	int retval = 0;
1229 	unsigned long flags;
1230 	u32 cap = 0;
1231 
1232 	if (ep == NULL || desc == NULL)
1233 		return -EINVAL;
1234 
1235 	spin_lock_irqsave(hwep->lock, flags);
1236 
1237 	/* only internal SW should enable ctrl endpts */
1238 
1239 	if (!list_empty(&hwep->qh.queue)) {
1240 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1241 		spin_unlock_irqrestore(hwep->lock, flags);
1242 		return -EBUSY;
1243 	}
1244 
1245 	hwep->ep.desc = desc;
1246 
1247 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1248 	hwep->num  = usb_endpoint_num(desc);
1249 	hwep->type = usb_endpoint_type(desc);
1250 
1251 	hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1252 	hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1253 
1254 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1255 		cap |= QH_IOS;
1256 
1257 	cap |= QH_ZLT;
1258 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1259 	/*
1260 	 * For ISO-TX, we set mult at QH as the largest value, and use
1261 	 * MultO at TD as real mult value.
1262 	 */
1263 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1264 		cap |= 3 << __ffs(QH_MULT);
1265 
1266 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1267 
1268 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1269 
1270 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1271 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1272 		retval = -EINVAL;
1273 	}
1274 
1275 	/*
1276 	 * Enable endpoints in the HW other than ep0 as ep0
1277 	 * is always enabled
1278 	 */
1279 	if (hwep->num)
1280 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1281 				       hwep->type);
1282 
1283 	spin_unlock_irqrestore(hwep->lock, flags);
1284 	return retval;
1285 }
1286 
1287 /**
1288  * ep_disable: endpoint is no longer usable
1289  *
1290  * Check usb_ep_disable() at "usb_gadget.h" for details
1291  */
1292 static int ep_disable(struct usb_ep *ep)
1293 {
1294 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1295 	int direction, retval = 0;
1296 	unsigned long flags;
1297 
1298 	if (ep == NULL)
1299 		return -EINVAL;
1300 	else if (hwep->ep.desc == NULL)
1301 		return -EBUSY;
1302 
1303 	spin_lock_irqsave(hwep->lock, flags);
1304 
1305 	/* only internal SW should disable ctrl endpts */
1306 
1307 	direction = hwep->dir;
1308 	do {
1309 		retval |= _ep_nuke(hwep);
1310 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1311 
1312 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1313 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1314 
1315 	} while (hwep->dir != direction);
1316 
1317 	hwep->ep.desc = NULL;
1318 
1319 	spin_unlock_irqrestore(hwep->lock, flags);
1320 	return retval;
1321 }
1322 
1323 /**
1324  * ep_alloc_request: allocate a request object to use with this endpoint
1325  *
1326  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1327  */
1328 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1329 {
1330 	struct ci_hw_req *hwreq = NULL;
1331 
1332 	if (ep == NULL)
1333 		return NULL;
1334 
1335 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1336 	if (hwreq != NULL) {
1337 		INIT_LIST_HEAD(&hwreq->queue);
1338 		INIT_LIST_HEAD(&hwreq->tds);
1339 	}
1340 
1341 	return (hwreq == NULL) ? NULL : &hwreq->req;
1342 }
1343 
1344 /**
1345  * ep_free_request: frees a request object
1346  *
1347  * Check usb_ep_free_request() at "usb_gadget.h" for details
1348  */
1349 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1350 {
1351 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1352 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1353 	struct td_node *node, *tmpnode;
1354 	unsigned long flags;
1355 
1356 	if (ep == NULL || req == NULL) {
1357 		return;
1358 	} else if (!list_empty(&hwreq->queue)) {
1359 		dev_err(hwep->ci->dev, "freeing queued request\n");
1360 		return;
1361 	}
1362 
1363 	spin_lock_irqsave(hwep->lock, flags);
1364 
1365 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1366 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1367 		list_del_init(&node->td);
1368 		node->ptr = NULL;
1369 		kfree(node);
1370 	}
1371 
1372 	kfree(hwreq);
1373 
1374 	spin_unlock_irqrestore(hwep->lock, flags);
1375 }
1376 
1377 /**
1378  * ep_queue: queues (submits) an I/O request to an endpoint
1379  *
1380  * Check usb_ep_queue()* at usb_gadget.h" for details
1381  */
1382 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1383 		    gfp_t __maybe_unused gfp_flags)
1384 {
1385 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1386 	int retval = 0;
1387 	unsigned long flags;
1388 
1389 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1390 		return -EINVAL;
1391 
1392 	spin_lock_irqsave(hwep->lock, flags);
1393 	retval = _ep_queue(ep, req, gfp_flags);
1394 	spin_unlock_irqrestore(hwep->lock, flags);
1395 	return retval;
1396 }
1397 
1398 /**
1399  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1400  *
1401  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1402  */
1403 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1404 {
1405 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1406 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1407 	unsigned long flags;
1408 	struct td_node *node, *tmpnode;
1409 
1410 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1411 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1412 		list_empty(&hwep->qh.queue))
1413 		return -EINVAL;
1414 
1415 	spin_lock_irqsave(hwep->lock, flags);
1416 
1417 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1418 
1419 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1420 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1421 		list_del(&node->td);
1422 		kfree(node);
1423 	}
1424 
1425 	/* pop request */
1426 	list_del_init(&hwreq->queue);
1427 
1428 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1429 
1430 	req->status = -ECONNRESET;
1431 
1432 	if (hwreq->req.complete != NULL) {
1433 		spin_unlock(hwep->lock);
1434 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1435 		spin_lock(hwep->lock);
1436 	}
1437 
1438 	spin_unlock_irqrestore(hwep->lock, flags);
1439 	return 0;
1440 }
1441 
1442 /**
1443  * ep_set_halt: sets the endpoint halt feature
1444  *
1445  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1446  */
1447 static int ep_set_halt(struct usb_ep *ep, int value)
1448 {
1449 	return _ep_set_halt(ep, value, true);
1450 }
1451 
1452 /**
1453  * ep_set_wedge: sets the halt feature and ignores clear requests
1454  *
1455  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1456  */
1457 static int ep_set_wedge(struct usb_ep *ep)
1458 {
1459 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1460 	unsigned long flags;
1461 
1462 	if (ep == NULL || hwep->ep.desc == NULL)
1463 		return -EINVAL;
1464 
1465 	spin_lock_irqsave(hwep->lock, flags);
1466 	hwep->wedge = 1;
1467 	spin_unlock_irqrestore(hwep->lock, flags);
1468 
1469 	return usb_ep_set_halt(ep);
1470 }
1471 
1472 /**
1473  * ep_fifo_flush: flushes contents of a fifo
1474  *
1475  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1476  */
1477 static void ep_fifo_flush(struct usb_ep *ep)
1478 {
1479 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1480 	unsigned long flags;
1481 
1482 	if (ep == NULL) {
1483 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1484 		return;
1485 	}
1486 
1487 	spin_lock_irqsave(hwep->lock, flags);
1488 
1489 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1490 
1491 	spin_unlock_irqrestore(hwep->lock, flags);
1492 }
1493 
1494 /**
1495  * Endpoint-specific part of the API to the USB controller hardware
1496  * Check "usb_gadget.h" for details
1497  */
1498 static const struct usb_ep_ops usb_ep_ops = {
1499 	.enable	       = ep_enable,
1500 	.disable       = ep_disable,
1501 	.alloc_request = ep_alloc_request,
1502 	.free_request  = ep_free_request,
1503 	.queue	       = ep_queue,
1504 	.dequeue       = ep_dequeue,
1505 	.set_halt      = ep_set_halt,
1506 	.set_wedge     = ep_set_wedge,
1507 	.fifo_flush    = ep_fifo_flush,
1508 };
1509 
1510 /******************************************************************************
1511  * GADGET block
1512  *****************************************************************************/
1513 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1514 {
1515 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1516 	unsigned long flags;
1517 	int gadget_ready = 0;
1518 
1519 	spin_lock_irqsave(&ci->lock, flags);
1520 	ci->vbus_active = is_active;
1521 	if (ci->driver)
1522 		gadget_ready = 1;
1523 	spin_unlock_irqrestore(&ci->lock, flags);
1524 
1525 	if (gadget_ready) {
1526 		if (is_active) {
1527 			pm_runtime_get_sync(&_gadget->dev);
1528 			hw_device_reset(ci);
1529 			hw_device_state(ci, ci->ep0out->qh.dma);
1530 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1531 			usb_udc_vbus_handler(_gadget, true);
1532 		} else {
1533 			usb_udc_vbus_handler(_gadget, false);
1534 			if (ci->driver)
1535 				ci->driver->disconnect(&ci->gadget);
1536 			hw_device_state(ci, 0);
1537 			if (ci->platdata->notify_event)
1538 				ci->platdata->notify_event(ci,
1539 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1540 			_gadget_stop_activity(&ci->gadget);
1541 			pm_runtime_put_sync(&_gadget->dev);
1542 			usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1543 		}
1544 	}
1545 
1546 	return 0;
1547 }
1548 
1549 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1550 {
1551 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1552 	unsigned long flags;
1553 	int ret = 0;
1554 
1555 	spin_lock_irqsave(&ci->lock, flags);
1556 	if (!ci->remote_wakeup) {
1557 		ret = -EOPNOTSUPP;
1558 		goto out;
1559 	}
1560 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1561 		ret = -EINVAL;
1562 		goto out;
1563 	}
1564 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1565 out:
1566 	spin_unlock_irqrestore(&ci->lock, flags);
1567 	return ret;
1568 }
1569 
1570 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1571 {
1572 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1573 
1574 	if (ci->usb_phy)
1575 		return usb_phy_set_power(ci->usb_phy, ma);
1576 	return -ENOTSUPP;
1577 }
1578 
1579 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1580 {
1581 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1582 	struct ci_hw_ep *hwep = ci->ep0in;
1583 	unsigned long flags;
1584 
1585 	spin_lock_irqsave(hwep->lock, flags);
1586 	_gadget->is_selfpowered = (is_on != 0);
1587 	spin_unlock_irqrestore(hwep->lock, flags);
1588 
1589 	return 0;
1590 }
1591 
1592 /* Change Data+ pullup status
1593  * this func is used by usb_gadget_connect/disconnet
1594  */
1595 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1596 {
1597 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1598 
1599 	/* Data+ pullup controlled by OTG state machine in OTG fsm mode */
1600 	if (ci_otg_is_fsm_mode(ci))
1601 		return 0;
1602 
1603 	pm_runtime_get_sync(&ci->gadget.dev);
1604 	if (is_on)
1605 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1606 	else
1607 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1608 	pm_runtime_put_sync(&ci->gadget.dev);
1609 
1610 	return 0;
1611 }
1612 
1613 static int ci_udc_start(struct usb_gadget *gadget,
1614 			 struct usb_gadget_driver *driver);
1615 static int ci_udc_stop(struct usb_gadget *gadget);
1616 /**
1617  * Device operations part of the API to the USB controller hardware,
1618  * which don't involve endpoints (or i/o)
1619  * Check  "usb_gadget.h" for details
1620  */
1621 static const struct usb_gadget_ops usb_gadget_ops = {
1622 	.vbus_session	= ci_udc_vbus_session,
1623 	.wakeup		= ci_udc_wakeup,
1624 	.set_selfpowered	= ci_udc_selfpowered,
1625 	.pullup		= ci_udc_pullup,
1626 	.vbus_draw	= ci_udc_vbus_draw,
1627 	.udc_start	= ci_udc_start,
1628 	.udc_stop	= ci_udc_stop,
1629 };
1630 
1631 static int init_eps(struct ci_hdrc *ci)
1632 {
1633 	int retval = 0, i, j;
1634 
1635 	for (i = 0; i < ci->hw_ep_max/2; i++)
1636 		for (j = RX; j <= TX; j++) {
1637 			int k = i + j * ci->hw_ep_max/2;
1638 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1639 
1640 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1641 					(j == TX)  ? "in" : "out");
1642 
1643 			hwep->ci          = ci;
1644 			hwep->lock         = &ci->lock;
1645 			hwep->td_pool      = ci->td_pool;
1646 
1647 			hwep->ep.name      = hwep->name;
1648 			hwep->ep.ops       = &usb_ep_ops;
1649 
1650 			if (i == 0) {
1651 				hwep->ep.caps.type_control = true;
1652 			} else {
1653 				hwep->ep.caps.type_iso = true;
1654 				hwep->ep.caps.type_bulk = true;
1655 				hwep->ep.caps.type_int = true;
1656 			}
1657 
1658 			if (j == TX)
1659 				hwep->ep.caps.dir_in = true;
1660 			else
1661 				hwep->ep.caps.dir_out = true;
1662 
1663 			/*
1664 			 * for ep0: maxP defined in desc, for other
1665 			 * eps, maxP is set by epautoconfig() called
1666 			 * by gadget layer
1667 			 */
1668 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1669 
1670 			INIT_LIST_HEAD(&hwep->qh.queue);
1671 			hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1672 						     &hwep->qh.dma);
1673 			if (hwep->qh.ptr == NULL)
1674 				retval = -ENOMEM;
1675 			else
1676 				memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1677 
1678 			/*
1679 			 * set up shorthands for ep0 out and in endpoints,
1680 			 * don't add to gadget's ep_list
1681 			 */
1682 			if (i == 0) {
1683 				if (j == RX)
1684 					ci->ep0out = hwep;
1685 				else
1686 					ci->ep0in = hwep;
1687 
1688 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1689 				continue;
1690 			}
1691 
1692 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1693 		}
1694 
1695 	return retval;
1696 }
1697 
1698 static void destroy_eps(struct ci_hdrc *ci)
1699 {
1700 	int i;
1701 
1702 	for (i = 0; i < ci->hw_ep_max; i++) {
1703 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1704 
1705 		if (hwep->pending_td)
1706 			free_pending_td(hwep);
1707 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1708 	}
1709 }
1710 
1711 /**
1712  * ci_udc_start: register a gadget driver
1713  * @gadget: our gadget
1714  * @driver: the driver being registered
1715  *
1716  * Interrupts are enabled here.
1717  */
1718 static int ci_udc_start(struct usb_gadget *gadget,
1719 			 struct usb_gadget_driver *driver)
1720 {
1721 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1722 	unsigned long flags;
1723 	int retval = -ENOMEM;
1724 
1725 	if (driver->disconnect == NULL)
1726 		return -EINVAL;
1727 
1728 
1729 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1730 	retval = usb_ep_enable(&ci->ep0out->ep);
1731 	if (retval)
1732 		return retval;
1733 
1734 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1735 	retval = usb_ep_enable(&ci->ep0in->ep);
1736 	if (retval)
1737 		return retval;
1738 
1739 	ci->driver = driver;
1740 
1741 	/* Start otg fsm for B-device */
1742 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1743 		ci_hdrc_otg_fsm_start(ci);
1744 		return retval;
1745 	}
1746 
1747 	pm_runtime_get_sync(&ci->gadget.dev);
1748 	if (ci->vbus_active) {
1749 		spin_lock_irqsave(&ci->lock, flags);
1750 		hw_device_reset(ci);
1751 	} else {
1752 		usb_udc_vbus_handler(&ci->gadget, false);
1753 		pm_runtime_put_sync(&ci->gadget.dev);
1754 		return retval;
1755 	}
1756 
1757 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1758 	spin_unlock_irqrestore(&ci->lock, flags);
1759 	if (retval)
1760 		pm_runtime_put_sync(&ci->gadget.dev);
1761 
1762 	return retval;
1763 }
1764 
1765 static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
1766 {
1767 	if (!ci_otg_is_fsm_mode(ci))
1768 		return;
1769 
1770 	mutex_lock(&ci->fsm.lock);
1771 	if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
1772 		ci->fsm.a_bidl_adis_tmout = 1;
1773 		ci_hdrc_otg_fsm_start(ci);
1774 	} else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
1775 		ci->fsm.protocol = PROTO_UNDEF;
1776 		ci->fsm.otg->state = OTG_STATE_UNDEFINED;
1777 	}
1778 	mutex_unlock(&ci->fsm.lock);
1779 }
1780 
1781 /**
1782  * ci_udc_stop: unregister a gadget driver
1783  */
1784 static int ci_udc_stop(struct usb_gadget *gadget)
1785 {
1786 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1787 	unsigned long flags;
1788 
1789 	spin_lock_irqsave(&ci->lock, flags);
1790 
1791 	if (ci->vbus_active) {
1792 		hw_device_state(ci, 0);
1793 		if (ci->platdata->notify_event)
1794 			ci->platdata->notify_event(ci,
1795 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1796 		spin_unlock_irqrestore(&ci->lock, flags);
1797 		_gadget_stop_activity(&ci->gadget);
1798 		spin_lock_irqsave(&ci->lock, flags);
1799 		pm_runtime_put(&ci->gadget.dev);
1800 	}
1801 
1802 	ci->driver = NULL;
1803 	spin_unlock_irqrestore(&ci->lock, flags);
1804 
1805 	ci_udc_stop_for_otg_fsm(ci);
1806 	return 0;
1807 }
1808 
1809 /******************************************************************************
1810  * BUS block
1811  *****************************************************************************/
1812 /**
1813  * udc_irq: ci interrupt handler
1814  *
1815  * This function returns IRQ_HANDLED if the IRQ has been handled
1816  * It locks access to registers
1817  */
1818 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1819 {
1820 	irqreturn_t retval;
1821 	u32 intr;
1822 
1823 	if (ci == NULL)
1824 		return IRQ_HANDLED;
1825 
1826 	spin_lock(&ci->lock);
1827 
1828 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1829 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1830 				USBMODE_CM_DC) {
1831 			spin_unlock(&ci->lock);
1832 			return IRQ_NONE;
1833 		}
1834 	}
1835 	intr = hw_test_and_clear_intr_active(ci);
1836 
1837 	if (intr) {
1838 		/* order defines priority - do NOT change it */
1839 		if (USBi_URI & intr)
1840 			isr_reset_handler(ci);
1841 
1842 		if (USBi_PCI & intr) {
1843 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1844 				USB_SPEED_HIGH : USB_SPEED_FULL;
1845 			if (ci->suspended && ci->driver->resume) {
1846 				spin_unlock(&ci->lock);
1847 				ci->driver->resume(&ci->gadget);
1848 				spin_lock(&ci->lock);
1849 				ci->suspended = 0;
1850 			}
1851 		}
1852 
1853 		if (USBi_UI  & intr)
1854 			isr_tr_complete_handler(ci);
1855 
1856 		if (USBi_SLI & intr) {
1857 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1858 			    ci->driver->suspend) {
1859 				ci->suspended = 1;
1860 				spin_unlock(&ci->lock);
1861 				ci->driver->suspend(&ci->gadget);
1862 				usb_gadget_set_state(&ci->gadget,
1863 						USB_STATE_SUSPENDED);
1864 				spin_lock(&ci->lock);
1865 			}
1866 		}
1867 		retval = IRQ_HANDLED;
1868 	} else {
1869 		retval = IRQ_NONE;
1870 	}
1871 	spin_unlock(&ci->lock);
1872 
1873 	return retval;
1874 }
1875 
1876 /**
1877  * udc_start: initialize gadget role
1878  * @ci: chipidea controller
1879  */
1880 static int udc_start(struct ci_hdrc *ci)
1881 {
1882 	struct device *dev = ci->dev;
1883 	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
1884 	int retval = 0;
1885 
1886 	spin_lock_init(&ci->lock);
1887 
1888 	ci->gadget.ops          = &usb_gadget_ops;
1889 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1890 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1891 	ci->gadget.name         = ci->platdata->name;
1892 	ci->gadget.otg_caps	= otg_caps;
1893 
1894 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
1895 						otg_caps->adp_support))
1896 		ci->gadget.is_otg = 1;
1897 
1898 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1899 
1900 	/* alloc resources */
1901 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1902 				       sizeof(struct ci_hw_qh),
1903 				       64, CI_HDRC_PAGE_SIZE);
1904 	if (ci->qh_pool == NULL)
1905 		return -ENOMEM;
1906 
1907 	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1908 				       sizeof(struct ci_hw_td),
1909 				       64, CI_HDRC_PAGE_SIZE);
1910 	if (ci->td_pool == NULL) {
1911 		retval = -ENOMEM;
1912 		goto free_qh_pool;
1913 	}
1914 
1915 	retval = init_eps(ci);
1916 	if (retval)
1917 		goto free_pools;
1918 
1919 	ci->gadget.ep0 = &ci->ep0in->ep;
1920 
1921 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1922 	if (retval)
1923 		goto destroy_eps;
1924 
1925 	pm_runtime_no_callbacks(&ci->gadget.dev);
1926 	pm_runtime_enable(&ci->gadget.dev);
1927 
1928 	return retval;
1929 
1930 destroy_eps:
1931 	destroy_eps(ci);
1932 free_pools:
1933 	dma_pool_destroy(ci->td_pool);
1934 free_qh_pool:
1935 	dma_pool_destroy(ci->qh_pool);
1936 	return retval;
1937 }
1938 
1939 /**
1940  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1941  *
1942  * No interrupts active, the IRQ has been released
1943  */
1944 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1945 {
1946 	if (!ci->roles[CI_ROLE_GADGET])
1947 		return;
1948 
1949 	usb_del_gadget_udc(&ci->gadget);
1950 
1951 	destroy_eps(ci);
1952 
1953 	dma_pool_destroy(ci->td_pool);
1954 	dma_pool_destroy(ci->qh_pool);
1955 }
1956 
1957 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1958 {
1959 	if (ci->is_otg)
1960 		/* Clear and enable BSV irq */
1961 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
1962 					OTGSC_BSVIS | OTGSC_BSVIE);
1963 
1964 	return 0;
1965 }
1966 
1967 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1968 {
1969 	/*
1970 	 * host doesn't care B_SESSION_VALID event
1971 	 * so clear and disbale BSV irq
1972 	 */
1973 	if (ci->is_otg)
1974 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
1975 }
1976 
1977 /**
1978  * ci_hdrc_gadget_init - initialize device related bits
1979  * ci: the controller
1980  *
1981  * This function initializes the gadget, if the device is "device capable".
1982  */
1983 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1984 {
1985 	struct ci_role_driver *rdrv;
1986 
1987 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1988 		return -ENXIO;
1989 
1990 	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1991 	if (!rdrv)
1992 		return -ENOMEM;
1993 
1994 	rdrv->start	= udc_id_switch_for_device;
1995 	rdrv->stop	= udc_id_switch_for_host;
1996 	rdrv->irq	= udc_irq;
1997 	rdrv->name	= "gadget";
1998 	ci->roles[CI_ROLE_GADGET] = rdrv;
1999 
2000 	return udc_start(ci);
2001 }
2002