xref: /linux/drivers/usb/chipidea/udc.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
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 "debug.h"
30 #include "otg.h"
31 #include "otg_fsm.h"
32 
33 /* control endpoint description */
34 static const struct usb_endpoint_descriptor
35 ctrl_endpt_out_desc = {
36 	.bLength         = USB_DT_ENDPOINT_SIZE,
37 	.bDescriptorType = USB_DT_ENDPOINT,
38 
39 	.bEndpointAddress = USB_DIR_OUT,
40 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
41 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
42 };
43 
44 static const struct usb_endpoint_descriptor
45 ctrl_endpt_in_desc = {
46 	.bLength         = USB_DT_ENDPOINT_SIZE,
47 	.bDescriptorType = USB_DT_ENDPOINT,
48 
49 	.bEndpointAddress = USB_DIR_IN,
50 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
51 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
52 };
53 
54 /**
55  * hw_ep_bit: calculates the bit number
56  * @num: endpoint number
57  * @dir: endpoint direction
58  *
59  * This function returns bit number
60  */
61 static inline int hw_ep_bit(int num, int dir)
62 {
63 	return num + (dir ? 16 : 0);
64 }
65 
66 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
67 {
68 	int fill = 16 - ci->hw_ep_max / 2;
69 
70 	if (n >= ci->hw_ep_max / 2)
71 		n += fill;
72 
73 	return n;
74 }
75 
76 /**
77  * hw_device_state: enables/disables interrupts (execute without interruption)
78  * @dma: 0 => disable, !0 => enable and set dma engine
79  *
80  * This function returns an error code
81  */
82 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
83 {
84 	if (dma) {
85 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
86 		/* interrupt, error, port change, reset, sleep/suspend */
87 		hw_write(ci, OP_USBINTR, ~0,
88 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
89 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
90 	} else {
91 		hw_write(ci, OP_USBINTR, ~0, 0);
92 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
93 	}
94 	return 0;
95 }
96 
97 /**
98  * hw_ep_flush: flush endpoint fifo (execute without interruption)
99  * @num: endpoint number
100  * @dir: endpoint direction
101  *
102  * This function returns an error code
103  */
104 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
105 {
106 	int n = hw_ep_bit(num, dir);
107 
108 	do {
109 		/* flush any pending transfer */
110 		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
111 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
112 			cpu_relax();
113 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
114 
115 	return 0;
116 }
117 
118 /**
119  * hw_ep_disable: disables endpoint (execute without interruption)
120  * @num: endpoint number
121  * @dir: endpoint direction
122  *
123  * This function returns an error code
124  */
125 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
126 {
127 	hw_ep_flush(ci, num, dir);
128 	hw_write(ci, OP_ENDPTCTRL + num,
129 		 dir ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
130 	return 0;
131 }
132 
133 /**
134  * hw_ep_enable: enables endpoint (execute without interruption)
135  * @num:  endpoint number
136  * @dir:  endpoint direction
137  * @type: endpoint type
138  *
139  * This function returns an error code
140  */
141 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
142 {
143 	u32 mask, data;
144 
145 	if (dir) {
146 		mask  = ENDPTCTRL_TXT;  /* type    */
147 		data  = type << __ffs(mask);
148 
149 		mask |= ENDPTCTRL_TXS;  /* unstall */
150 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
151 		data |= ENDPTCTRL_TXR;
152 		mask |= ENDPTCTRL_TXE;  /* enable  */
153 		data |= ENDPTCTRL_TXE;
154 	} else {
155 		mask  = ENDPTCTRL_RXT;  /* type    */
156 		data  = type << __ffs(mask);
157 
158 		mask |= ENDPTCTRL_RXS;  /* unstall */
159 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
160 		data |= ENDPTCTRL_RXR;
161 		mask |= ENDPTCTRL_RXE;  /* enable  */
162 		data |= ENDPTCTRL_RXE;
163 	}
164 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
165 	return 0;
166 }
167 
168 /**
169  * hw_ep_get_halt: return endpoint halt status
170  * @num: endpoint number
171  * @dir: endpoint direction
172  *
173  * This function returns 1 if endpoint halted
174  */
175 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
176 {
177 	u32 mask = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
178 
179 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
180 }
181 
182 /**
183  * hw_ep_prime: primes endpoint (execute without interruption)
184  * @num:     endpoint number
185  * @dir:     endpoint direction
186  * @is_ctrl: true if control endpoint
187  *
188  * This function returns an error code
189  */
190 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
191 {
192 	int n = hw_ep_bit(num, dir);
193 
194 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
195 		return -EAGAIN;
196 
197 	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
198 
199 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
200 		cpu_relax();
201 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
202 		return -EAGAIN;
203 
204 	/* status shoult be tested according with manual but it doesn't work */
205 	return 0;
206 }
207 
208 /**
209  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
210  *                 without interruption)
211  * @num:   endpoint number
212  * @dir:   endpoint direction
213  * @value: true => stall, false => unstall
214  *
215  * This function returns an error code
216  */
217 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
218 {
219 	if (value != 0 && value != 1)
220 		return -EINVAL;
221 
222 	do {
223 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
224 		u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
225 		u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
226 
227 		/* data toggle - reserved for EP0 but it's in ESS */
228 		hw_write(ci, reg, mask_xs|mask_xr,
229 			  value ? mask_xs : mask_xr);
230 	} while (value != hw_ep_get_halt(ci, num, dir));
231 
232 	return 0;
233 }
234 
235 /**
236  * hw_is_port_high_speed: test if port is high speed
237  *
238  * This function returns true if high speed port
239  */
240 static int hw_port_is_high_speed(struct ci_hdrc *ci)
241 {
242 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
243 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
244 }
245 
246 /**
247  * hw_test_and_clear_complete: test & clear complete status (execute without
248  *                             interruption)
249  * @n: endpoint number
250  *
251  * This function returns complete status
252  */
253 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
254 {
255 	n = ep_to_bit(ci, n);
256 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
257 }
258 
259 /**
260  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
261  *                                without interruption)
262  *
263  * This function returns active interrutps
264  */
265 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
266 {
267 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
268 
269 	hw_write(ci, OP_USBSTS, ~0, reg);
270 	return reg;
271 }
272 
273 /**
274  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
275  *                                interruption)
276  *
277  * This function returns guard value
278  */
279 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
280 {
281 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
282 }
283 
284 /**
285  * hw_test_and_set_setup_guard: test & set setup guard (execute without
286  *                              interruption)
287  *
288  * This function returns guard value
289  */
290 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
291 {
292 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
293 }
294 
295 /**
296  * hw_usb_set_address: configures USB address (execute without interruption)
297  * @value: new USB address
298  *
299  * This function explicitly sets the address, without the "USBADRA" (advance)
300  * feature, which is not supported by older versions of the controller.
301  */
302 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
303 {
304 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
305 		 value << __ffs(DEVICEADDR_USBADR));
306 }
307 
308 /**
309  * hw_usb_reset: restart device after a bus reset (execute without
310  *               interruption)
311  *
312  * This function returns an error code
313  */
314 static int hw_usb_reset(struct ci_hdrc *ci)
315 {
316 	hw_usb_set_address(ci, 0);
317 
318 	/* ESS flushes only at end?!? */
319 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
320 
321 	/* clear setup token semaphores */
322 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
323 
324 	/* clear complete status */
325 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
326 
327 	/* wait until all bits cleared */
328 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
329 		udelay(10);             /* not RTOS friendly */
330 
331 	/* reset all endpoints ? */
332 
333 	/* reset internal status and wait for further instructions
334 	   no need to verify the port reset status (ESS does it) */
335 
336 	return 0;
337 }
338 
339 /******************************************************************************
340  * UTIL block
341  *****************************************************************************/
342 
343 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
344 			  unsigned length)
345 {
346 	int i;
347 	u32 temp;
348 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
349 						  GFP_ATOMIC);
350 
351 	if (node == NULL)
352 		return -ENOMEM;
353 
354 	node->ptr = dma_pool_alloc(hwep->td_pool, GFP_ATOMIC,
355 				   &node->dma);
356 	if (node->ptr == NULL) {
357 		kfree(node);
358 		return -ENOMEM;
359 	}
360 
361 	memset(node->ptr, 0, sizeof(struct ci_hw_td));
362 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
363 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
364 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
365 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
366 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
367 
368 		if (hwreq->req.length == 0
369 				|| hwreq->req.length % hwep->ep.maxpacket)
370 			mul++;
371 		node->ptr->token |= mul << __ffs(TD_MULTO);
372 	}
373 
374 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
375 	if (length) {
376 		node->ptr->page[0] = cpu_to_le32(temp);
377 		for (i = 1; i < TD_PAGE_COUNT; i++) {
378 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
379 			page &= ~TD_RESERVED_MASK;
380 			node->ptr->page[i] = cpu_to_le32(page);
381 		}
382 	}
383 
384 	hwreq->req.actual += length;
385 
386 	if (!list_empty(&hwreq->tds)) {
387 		/* get the last entry */
388 		lastnode = list_entry(hwreq->tds.prev,
389 				struct td_node, td);
390 		lastnode->ptr->next = cpu_to_le32(node->dma);
391 	}
392 
393 	INIT_LIST_HEAD(&node->td);
394 	list_add_tail(&node->td, &hwreq->tds);
395 
396 	return 0;
397 }
398 
399 /**
400  * _usb_addr: calculates endpoint address from direction & number
401  * @ep:  endpoint
402  */
403 static inline u8 _usb_addr(struct ci_hw_ep *ep)
404 {
405 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
406 }
407 
408 /**
409  * _hardware_queue: configures a request at hardware level
410  * @gadget: gadget
411  * @hwep:   endpoint
412  *
413  * This function returns an error code
414  */
415 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
416 {
417 	struct ci_hdrc *ci = hwep->ci;
418 	int ret = 0;
419 	unsigned rest = hwreq->req.length;
420 	int pages = TD_PAGE_COUNT;
421 	struct td_node *firstnode, *lastnode;
422 
423 	/* don't queue twice */
424 	if (hwreq->req.status == -EALREADY)
425 		return -EALREADY;
426 
427 	hwreq->req.status = -EALREADY;
428 
429 	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
430 	if (ret)
431 		return ret;
432 
433 	/*
434 	 * The first buffer could be not page aligned.
435 	 * In that case we have to span into one extra td.
436 	 */
437 	if (hwreq->req.dma % PAGE_SIZE)
438 		pages--;
439 
440 	if (rest == 0)
441 		add_td_to_list(hwep, hwreq, 0);
442 
443 	while (rest > 0) {
444 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
445 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
446 		add_td_to_list(hwep, hwreq, count);
447 		rest -= count;
448 	}
449 
450 	if (hwreq->req.zero && hwreq->req.length
451 	    && (hwreq->req.length % hwep->ep.maxpacket == 0))
452 		add_td_to_list(hwep, hwreq, 0);
453 
454 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
455 
456 	lastnode = list_entry(hwreq->tds.prev,
457 		struct td_node, td);
458 
459 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
460 	if (!hwreq->req.no_interrupt)
461 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
462 	wmb();
463 
464 	hwreq->req.actual = 0;
465 	if (!list_empty(&hwep->qh.queue)) {
466 		struct ci_hw_req *hwreqprev;
467 		int n = hw_ep_bit(hwep->num, hwep->dir);
468 		int tmp_stat;
469 		struct td_node *prevlastnode;
470 		u32 next = firstnode->dma & TD_ADDR_MASK;
471 
472 		hwreqprev = list_entry(hwep->qh.queue.prev,
473 				struct ci_hw_req, queue);
474 		prevlastnode = list_entry(hwreqprev->tds.prev,
475 				struct td_node, td);
476 
477 		prevlastnode->ptr->next = cpu_to_le32(next);
478 		wmb();
479 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
480 			goto done;
481 		do {
482 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
483 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
484 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
485 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
486 		if (tmp_stat)
487 			goto done;
488 	}
489 
490 	/*  QH configuration */
491 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
492 	hwep->qh.ptr->td.token &=
493 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
494 
495 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
496 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
497 
498 		if (hwreq->req.length == 0
499 				|| hwreq->req.length % hwep->ep.maxpacket)
500 			mul++;
501 		hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
502 	}
503 
504 	wmb();   /* synchronize before ep prime */
505 
506 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
507 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
508 done:
509 	return ret;
510 }
511 
512 /*
513  * free_pending_td: remove a pending request for the endpoint
514  * @hwep: endpoint
515  */
516 static void free_pending_td(struct ci_hw_ep *hwep)
517 {
518 	struct td_node *pending = hwep->pending_td;
519 
520 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
521 	hwep->pending_td = NULL;
522 	kfree(pending);
523 }
524 
525 /**
526  * _hardware_dequeue: handles a request at hardware level
527  * @gadget: gadget
528  * @hwep:   endpoint
529  *
530  * This function returns an error code
531  */
532 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
533 {
534 	u32 tmptoken;
535 	struct td_node *node, *tmpnode;
536 	unsigned remaining_length;
537 	unsigned actual = hwreq->req.length;
538 
539 	if (hwreq->req.status != -EALREADY)
540 		return -EINVAL;
541 
542 	hwreq->req.status = 0;
543 
544 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
545 		tmptoken = le32_to_cpu(node->ptr->token);
546 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
547 			hwreq->req.status = -EALREADY;
548 			return -EBUSY;
549 		}
550 
551 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
552 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
553 		actual -= remaining_length;
554 
555 		hwreq->req.status = tmptoken & TD_STATUS;
556 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
557 			hwreq->req.status = -EPIPE;
558 			break;
559 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
560 			hwreq->req.status = -EPROTO;
561 			break;
562 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
563 			hwreq->req.status = -EILSEQ;
564 			break;
565 		}
566 
567 		if (remaining_length) {
568 			if (hwep->dir) {
569 				hwreq->req.status = -EPROTO;
570 				break;
571 			}
572 		}
573 		/*
574 		 * As the hardware could still address the freed td
575 		 * which will run the udc unusable, the cleanup of the
576 		 * td has to be delayed by one.
577 		 */
578 		if (hwep->pending_td)
579 			free_pending_td(hwep);
580 
581 		hwep->pending_td = node;
582 		list_del_init(&node->td);
583 	}
584 
585 	usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
586 
587 	hwreq->req.actual += actual;
588 
589 	if (hwreq->req.status)
590 		return hwreq->req.status;
591 
592 	return hwreq->req.actual;
593 }
594 
595 /**
596  * _ep_nuke: dequeues all endpoint requests
597  * @hwep: endpoint
598  *
599  * This function returns an error code
600  * Caller must hold lock
601  */
602 static int _ep_nuke(struct ci_hw_ep *hwep)
603 __releases(hwep->lock)
604 __acquires(hwep->lock)
605 {
606 	struct td_node *node, *tmpnode;
607 	if (hwep == NULL)
608 		return -EINVAL;
609 
610 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
611 
612 	while (!list_empty(&hwep->qh.queue)) {
613 
614 		/* pop oldest request */
615 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
616 						     struct ci_hw_req, queue);
617 
618 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
619 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
620 			list_del_init(&node->td);
621 			node->ptr = NULL;
622 			kfree(node);
623 		}
624 
625 		list_del_init(&hwreq->queue);
626 		hwreq->req.status = -ESHUTDOWN;
627 
628 		if (hwreq->req.complete != NULL) {
629 			spin_unlock(hwep->lock);
630 			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
631 			spin_lock(hwep->lock);
632 		}
633 	}
634 
635 	if (hwep->pending_td)
636 		free_pending_td(hwep);
637 
638 	return 0;
639 }
640 
641 /**
642  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
643  * @gadget: gadget
644  *
645  * This function returns an error code
646  */
647 static int _gadget_stop_activity(struct usb_gadget *gadget)
648 {
649 	struct usb_ep *ep;
650 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
651 	unsigned long flags;
652 
653 	spin_lock_irqsave(&ci->lock, flags);
654 	ci->gadget.speed = USB_SPEED_UNKNOWN;
655 	ci->remote_wakeup = 0;
656 	ci->suspended = 0;
657 	spin_unlock_irqrestore(&ci->lock, flags);
658 
659 	/* flush all endpoints */
660 	gadget_for_each_ep(ep, gadget) {
661 		usb_ep_fifo_flush(ep);
662 	}
663 	usb_ep_fifo_flush(&ci->ep0out->ep);
664 	usb_ep_fifo_flush(&ci->ep0in->ep);
665 
666 	/* make sure to disable all endpoints */
667 	gadget_for_each_ep(ep, gadget) {
668 		usb_ep_disable(ep);
669 	}
670 
671 	if (ci->status != NULL) {
672 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
673 		ci->status = NULL;
674 	}
675 
676 	return 0;
677 }
678 
679 /******************************************************************************
680  * ISR block
681  *****************************************************************************/
682 /**
683  * isr_reset_handler: USB reset interrupt handler
684  * @ci: UDC device
685  *
686  * This function resets USB engine after a bus reset occurred
687  */
688 static void isr_reset_handler(struct ci_hdrc *ci)
689 __releases(ci->lock)
690 __acquires(ci->lock)
691 {
692 	int retval;
693 
694 	spin_unlock(&ci->lock);
695 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
696 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
697 
698 	retval = _gadget_stop_activity(&ci->gadget);
699 	if (retval)
700 		goto done;
701 
702 	retval = hw_usb_reset(ci);
703 	if (retval)
704 		goto done;
705 
706 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
707 	if (ci->status == NULL)
708 		retval = -ENOMEM;
709 
710 done:
711 	spin_lock(&ci->lock);
712 
713 	if (retval)
714 		dev_err(ci->dev, "error: %i\n", retval);
715 }
716 
717 /**
718  * isr_get_status_complete: get_status request complete function
719  * @ep:  endpoint
720  * @req: request handled
721  *
722  * Caller must release lock
723  */
724 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
725 {
726 	if (ep == NULL || req == NULL)
727 		return;
728 
729 	kfree(req->buf);
730 	usb_ep_free_request(ep, req);
731 }
732 
733 /**
734  * _ep_queue: queues (submits) an I/O request to an endpoint
735  *
736  * Caller must hold lock
737  */
738 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
739 		    gfp_t __maybe_unused gfp_flags)
740 {
741 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
742 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
743 	struct ci_hdrc *ci = hwep->ci;
744 	int retval = 0;
745 
746 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
747 		return -EINVAL;
748 
749 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
750 		if (req->length)
751 			hwep = (ci->ep0_dir == RX) ?
752 			       ci->ep0out : ci->ep0in;
753 		if (!list_empty(&hwep->qh.queue)) {
754 			_ep_nuke(hwep);
755 			retval = -EOVERFLOW;
756 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
757 				 _usb_addr(hwep));
758 		}
759 	}
760 
761 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
762 	    hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
763 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
764 		return -EMSGSIZE;
765 	}
766 
767 	/* first nuke then test link, e.g. previous status has not sent */
768 	if (!list_empty(&hwreq->queue)) {
769 		dev_err(hwep->ci->dev, "request already in queue\n");
770 		return -EBUSY;
771 	}
772 
773 	/* push request */
774 	hwreq->req.status = -EINPROGRESS;
775 	hwreq->req.actual = 0;
776 
777 	retval = _hardware_enqueue(hwep, hwreq);
778 
779 	if (retval == -EALREADY)
780 		retval = 0;
781 	if (!retval)
782 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
783 
784 	return retval;
785 }
786 
787 /**
788  * isr_get_status_response: get_status request response
789  * @ci: ci struct
790  * @setup: setup request packet
791  *
792  * This function returns an error code
793  */
794 static int isr_get_status_response(struct ci_hdrc *ci,
795 				   struct usb_ctrlrequest *setup)
796 __releases(hwep->lock)
797 __acquires(hwep->lock)
798 {
799 	struct ci_hw_ep *hwep = ci->ep0in;
800 	struct usb_request *req = NULL;
801 	gfp_t gfp_flags = GFP_ATOMIC;
802 	int dir, num, retval;
803 
804 	if (hwep == NULL || setup == NULL)
805 		return -EINVAL;
806 
807 	spin_unlock(hwep->lock);
808 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
809 	spin_lock(hwep->lock);
810 	if (req == NULL)
811 		return -ENOMEM;
812 
813 	req->complete = isr_get_status_complete;
814 	req->length   = 2;
815 	req->buf      = kzalloc(req->length, gfp_flags);
816 	if (req->buf == NULL) {
817 		retval = -ENOMEM;
818 		goto err_free_req;
819 	}
820 
821 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
822 		/* Assume that device is bus powered for now. */
823 		*(u16 *)req->buf = ci->remote_wakeup << 1;
824 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
825 		   == USB_RECIP_ENDPOINT) {
826 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
827 			TX : RX;
828 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
829 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
830 	}
831 	/* else do nothing; reserved for future use */
832 
833 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
834 	if (retval)
835 		goto err_free_buf;
836 
837 	return 0;
838 
839  err_free_buf:
840 	kfree(req->buf);
841  err_free_req:
842 	spin_unlock(hwep->lock);
843 	usb_ep_free_request(&hwep->ep, req);
844 	spin_lock(hwep->lock);
845 	return retval;
846 }
847 
848 /**
849  * isr_setup_status_complete: setup_status request complete function
850  * @ep:  endpoint
851  * @req: request handled
852  *
853  * Caller must release lock. Put the port in test mode if test mode
854  * feature is selected.
855  */
856 static void
857 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
858 {
859 	struct ci_hdrc *ci = req->context;
860 	unsigned long flags;
861 
862 	if (ci->setaddr) {
863 		hw_usb_set_address(ci, ci->address);
864 		ci->setaddr = false;
865 		if (ci->address)
866 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
867 	}
868 
869 	spin_lock_irqsave(&ci->lock, flags);
870 	if (ci->test_mode)
871 		hw_port_test_set(ci, ci->test_mode);
872 	spin_unlock_irqrestore(&ci->lock, flags);
873 }
874 
875 /**
876  * isr_setup_status_phase: queues the status phase of a setup transation
877  * @ci: ci struct
878  *
879  * This function returns an error code
880  */
881 static int isr_setup_status_phase(struct ci_hdrc *ci)
882 {
883 	int retval;
884 	struct ci_hw_ep *hwep;
885 
886 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
887 	ci->status->context = ci;
888 	ci->status->complete = isr_setup_status_complete;
889 
890 	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
891 
892 	return retval;
893 }
894 
895 /**
896  * isr_tr_complete_low: transaction complete low level handler
897  * @hwep: endpoint
898  *
899  * This function returns an error code
900  * Caller must hold lock
901  */
902 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
903 __releases(hwep->lock)
904 __acquires(hwep->lock)
905 {
906 	struct ci_hw_req *hwreq, *hwreqtemp;
907 	struct ci_hw_ep *hweptemp = hwep;
908 	int retval = 0;
909 
910 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
911 			queue) {
912 		retval = _hardware_dequeue(hwep, hwreq);
913 		if (retval < 0)
914 			break;
915 		list_del_init(&hwreq->queue);
916 		if (hwreq->req.complete != NULL) {
917 			spin_unlock(hwep->lock);
918 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
919 					hwreq->req.length)
920 				hweptemp = hwep->ci->ep0in;
921 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
922 			spin_lock(hwep->lock);
923 		}
924 	}
925 
926 	if (retval == -EBUSY)
927 		retval = 0;
928 
929 	return retval;
930 }
931 
932 /**
933  * isr_setup_packet_handler: setup packet handler
934  * @ci: UDC descriptor
935  *
936  * This function handles setup packet
937  */
938 static void isr_setup_packet_handler(struct ci_hdrc *ci)
939 __releases(ci->lock)
940 __acquires(ci->lock)
941 {
942 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
943 	struct usb_ctrlrequest req;
944 	int type, num, dir, err = -EINVAL;
945 	u8 tmode = 0;
946 
947 	/*
948 	 * Flush data and handshake transactions of previous
949 	 * setup packet.
950 	 */
951 	_ep_nuke(ci->ep0out);
952 	_ep_nuke(ci->ep0in);
953 
954 	/* read_setup_packet */
955 	do {
956 		hw_test_and_set_setup_guard(ci);
957 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
958 	} while (!hw_test_and_clear_setup_guard(ci));
959 
960 	type = req.bRequestType;
961 
962 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
963 
964 	switch (req.bRequest) {
965 	case USB_REQ_CLEAR_FEATURE:
966 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
967 				le16_to_cpu(req.wValue) ==
968 				USB_ENDPOINT_HALT) {
969 			if (req.wLength != 0)
970 				break;
971 			num  = le16_to_cpu(req.wIndex);
972 			dir = num & USB_ENDPOINT_DIR_MASK;
973 			num &= USB_ENDPOINT_NUMBER_MASK;
974 			if (dir) /* TX */
975 				num += ci->hw_ep_max / 2;
976 			if (!ci->ci_hw_ep[num].wedge) {
977 				spin_unlock(&ci->lock);
978 				err = usb_ep_clear_halt(
979 					&ci->ci_hw_ep[num].ep);
980 				spin_lock(&ci->lock);
981 				if (err)
982 					break;
983 			}
984 			err = isr_setup_status_phase(ci);
985 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
986 				le16_to_cpu(req.wValue) ==
987 				USB_DEVICE_REMOTE_WAKEUP) {
988 			if (req.wLength != 0)
989 				break;
990 			ci->remote_wakeup = 0;
991 			err = isr_setup_status_phase(ci);
992 		} else {
993 			goto delegate;
994 		}
995 		break;
996 	case USB_REQ_GET_STATUS:
997 		if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
998 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
999 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1000 			goto delegate;
1001 		if (le16_to_cpu(req.wLength) != 2 ||
1002 		    le16_to_cpu(req.wValue)  != 0)
1003 			break;
1004 		err = isr_get_status_response(ci, &req);
1005 		break;
1006 	case USB_REQ_SET_ADDRESS:
1007 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1008 			goto delegate;
1009 		if (le16_to_cpu(req.wLength) != 0 ||
1010 		    le16_to_cpu(req.wIndex)  != 0)
1011 			break;
1012 		ci->address = (u8)le16_to_cpu(req.wValue);
1013 		ci->setaddr = true;
1014 		err = isr_setup_status_phase(ci);
1015 		break;
1016 	case USB_REQ_SET_FEATURE:
1017 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1018 				le16_to_cpu(req.wValue) ==
1019 				USB_ENDPOINT_HALT) {
1020 			if (req.wLength != 0)
1021 				break;
1022 			num  = le16_to_cpu(req.wIndex);
1023 			dir = num & USB_ENDPOINT_DIR_MASK;
1024 			num &= USB_ENDPOINT_NUMBER_MASK;
1025 			if (dir) /* TX */
1026 				num += ci->hw_ep_max / 2;
1027 
1028 			spin_unlock(&ci->lock);
1029 			err = usb_ep_set_halt(&ci->ci_hw_ep[num].ep);
1030 			spin_lock(&ci->lock);
1031 			if (!err)
1032 				isr_setup_status_phase(ci);
1033 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1034 			if (req.wLength != 0)
1035 				break;
1036 			switch (le16_to_cpu(req.wValue)) {
1037 			case USB_DEVICE_REMOTE_WAKEUP:
1038 				ci->remote_wakeup = 1;
1039 				err = isr_setup_status_phase(ci);
1040 				break;
1041 			case USB_DEVICE_TEST_MODE:
1042 				tmode = le16_to_cpu(req.wIndex) >> 8;
1043 				switch (tmode) {
1044 				case TEST_J:
1045 				case TEST_K:
1046 				case TEST_SE0_NAK:
1047 				case TEST_PACKET:
1048 				case TEST_FORCE_EN:
1049 					ci->test_mode = tmode;
1050 					err = isr_setup_status_phase(
1051 							ci);
1052 					break;
1053 				default:
1054 					break;
1055 				}
1056 				break;
1057 			case USB_DEVICE_B_HNP_ENABLE:
1058 				if (ci_otg_is_fsm_mode(ci)) {
1059 					ci->gadget.b_hnp_enable = 1;
1060 					err = isr_setup_status_phase(
1061 							ci);
1062 				}
1063 				break;
1064 			default:
1065 				goto delegate;
1066 			}
1067 		} else {
1068 			goto delegate;
1069 		}
1070 		break;
1071 	default:
1072 delegate:
1073 		if (req.wLength == 0)   /* no data phase */
1074 			ci->ep0_dir = TX;
1075 
1076 		spin_unlock(&ci->lock);
1077 		err = ci->driver->setup(&ci->gadget, &req);
1078 		spin_lock(&ci->lock);
1079 		break;
1080 	}
1081 
1082 	if (err < 0) {
1083 		spin_unlock(&ci->lock);
1084 		if (usb_ep_set_halt(&hwep->ep))
1085 			dev_err(ci->dev, "error: ep_set_halt\n");
1086 		spin_lock(&ci->lock);
1087 	}
1088 }
1089 
1090 /**
1091  * isr_tr_complete_handler: transaction complete interrupt handler
1092  * @ci: UDC descriptor
1093  *
1094  * This function handles traffic events
1095  */
1096 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1097 __releases(ci->lock)
1098 __acquires(ci->lock)
1099 {
1100 	unsigned i;
1101 	int err;
1102 
1103 	for (i = 0; i < ci->hw_ep_max; i++) {
1104 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1105 
1106 		if (hwep->ep.desc == NULL)
1107 			continue;   /* not configured */
1108 
1109 		if (hw_test_and_clear_complete(ci, i)) {
1110 			err = isr_tr_complete_low(hwep);
1111 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1112 				if (err > 0)   /* needs status phase */
1113 					err = isr_setup_status_phase(ci);
1114 				if (err < 0) {
1115 					spin_unlock(&ci->lock);
1116 					if (usb_ep_set_halt(&hwep->ep))
1117 						dev_err(ci->dev,
1118 							"error: ep_set_halt\n");
1119 					spin_lock(&ci->lock);
1120 				}
1121 			}
1122 		}
1123 
1124 		/* Only handle setup packet below */
1125 		if (i == 0 &&
1126 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1127 			isr_setup_packet_handler(ci);
1128 	}
1129 }
1130 
1131 /******************************************************************************
1132  * ENDPT block
1133  *****************************************************************************/
1134 /**
1135  * ep_enable: configure endpoint, making it usable
1136  *
1137  * Check usb_ep_enable() at "usb_gadget.h" for details
1138  */
1139 static int ep_enable(struct usb_ep *ep,
1140 		     const struct usb_endpoint_descriptor *desc)
1141 {
1142 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1143 	int retval = 0;
1144 	unsigned long flags;
1145 	u32 cap = 0;
1146 
1147 	if (ep == NULL || desc == NULL)
1148 		return -EINVAL;
1149 
1150 	spin_lock_irqsave(hwep->lock, flags);
1151 
1152 	/* only internal SW should enable ctrl endpts */
1153 
1154 	hwep->ep.desc = desc;
1155 
1156 	if (!list_empty(&hwep->qh.queue))
1157 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1158 
1159 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1160 	hwep->num  = usb_endpoint_num(desc);
1161 	hwep->type = usb_endpoint_type(desc);
1162 
1163 	hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1164 	hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1165 
1166 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1167 		cap |= QH_IOS;
1168 
1169 	cap |= QH_ZLT;
1170 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1171 	/*
1172 	 * For ISO-TX, we set mult at QH as the largest value, and use
1173 	 * MultO at TD as real mult value.
1174 	 */
1175 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1176 		cap |= 3 << __ffs(QH_MULT);
1177 
1178 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1179 
1180 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1181 
1182 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1183 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1184 		retval = -EINVAL;
1185 	}
1186 
1187 	/*
1188 	 * Enable endpoints in the HW other than ep0 as ep0
1189 	 * is always enabled
1190 	 */
1191 	if (hwep->num)
1192 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1193 				       hwep->type);
1194 
1195 	spin_unlock_irqrestore(hwep->lock, flags);
1196 	return retval;
1197 }
1198 
1199 /**
1200  * ep_disable: endpoint is no longer usable
1201  *
1202  * Check usb_ep_disable() at "usb_gadget.h" for details
1203  */
1204 static int ep_disable(struct usb_ep *ep)
1205 {
1206 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1207 	int direction, retval = 0;
1208 	unsigned long flags;
1209 
1210 	if (ep == NULL)
1211 		return -EINVAL;
1212 	else if (hwep->ep.desc == NULL)
1213 		return -EBUSY;
1214 
1215 	spin_lock_irqsave(hwep->lock, flags);
1216 
1217 	/* only internal SW should disable ctrl endpts */
1218 
1219 	direction = hwep->dir;
1220 	do {
1221 		retval |= _ep_nuke(hwep);
1222 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1223 
1224 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1225 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1226 
1227 	} while (hwep->dir != direction);
1228 
1229 	hwep->ep.desc = NULL;
1230 
1231 	spin_unlock_irqrestore(hwep->lock, flags);
1232 	return retval;
1233 }
1234 
1235 /**
1236  * ep_alloc_request: allocate a request object to use with this endpoint
1237  *
1238  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1239  */
1240 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1241 {
1242 	struct ci_hw_req *hwreq = NULL;
1243 
1244 	if (ep == NULL)
1245 		return NULL;
1246 
1247 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1248 	if (hwreq != NULL) {
1249 		INIT_LIST_HEAD(&hwreq->queue);
1250 		INIT_LIST_HEAD(&hwreq->tds);
1251 	}
1252 
1253 	return (hwreq == NULL) ? NULL : &hwreq->req;
1254 }
1255 
1256 /**
1257  * ep_free_request: frees a request object
1258  *
1259  * Check usb_ep_free_request() at "usb_gadget.h" for details
1260  */
1261 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1262 {
1263 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1264 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1265 	struct td_node *node, *tmpnode;
1266 	unsigned long flags;
1267 
1268 	if (ep == NULL || req == NULL) {
1269 		return;
1270 	} else if (!list_empty(&hwreq->queue)) {
1271 		dev_err(hwep->ci->dev, "freeing queued request\n");
1272 		return;
1273 	}
1274 
1275 	spin_lock_irqsave(hwep->lock, flags);
1276 
1277 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1278 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1279 		list_del_init(&node->td);
1280 		node->ptr = NULL;
1281 		kfree(node);
1282 	}
1283 
1284 	kfree(hwreq);
1285 
1286 	spin_unlock_irqrestore(hwep->lock, flags);
1287 }
1288 
1289 /**
1290  * ep_queue: queues (submits) an I/O request to an endpoint
1291  *
1292  * Check usb_ep_queue()* at usb_gadget.h" for details
1293  */
1294 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1295 		    gfp_t __maybe_unused gfp_flags)
1296 {
1297 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1298 	int retval = 0;
1299 	unsigned long flags;
1300 
1301 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1302 		return -EINVAL;
1303 
1304 	spin_lock_irqsave(hwep->lock, flags);
1305 	retval = _ep_queue(ep, req, gfp_flags);
1306 	spin_unlock_irqrestore(hwep->lock, flags);
1307 	return retval;
1308 }
1309 
1310 /**
1311  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1312  *
1313  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1314  */
1315 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1316 {
1317 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1318 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1319 	unsigned long flags;
1320 	struct td_node *node, *tmpnode;
1321 
1322 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1323 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1324 		list_empty(&hwep->qh.queue))
1325 		return -EINVAL;
1326 
1327 	spin_lock_irqsave(hwep->lock, flags);
1328 
1329 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1330 
1331 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1332 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1333 		list_del(&node->td);
1334 		kfree(node);
1335 	}
1336 
1337 	/* pop request */
1338 	list_del_init(&hwreq->queue);
1339 
1340 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1341 
1342 	req->status = -ECONNRESET;
1343 
1344 	if (hwreq->req.complete != NULL) {
1345 		spin_unlock(hwep->lock);
1346 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1347 		spin_lock(hwep->lock);
1348 	}
1349 
1350 	spin_unlock_irqrestore(hwep->lock, flags);
1351 	return 0;
1352 }
1353 
1354 /**
1355  * ep_set_halt: sets the endpoint halt feature
1356  *
1357  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1358  */
1359 static int ep_set_halt(struct usb_ep *ep, int value)
1360 {
1361 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1362 	int direction, retval = 0;
1363 	unsigned long flags;
1364 
1365 	if (ep == NULL || hwep->ep.desc == NULL)
1366 		return -EINVAL;
1367 
1368 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
1369 		return -EOPNOTSUPP;
1370 
1371 	spin_lock_irqsave(hwep->lock, flags);
1372 
1373 #ifndef STALL_IN
1374 	/* g_file_storage MS compliant but g_zero fails chapter 9 compliance */
1375 	if (value && hwep->type == USB_ENDPOINT_XFER_BULK && hwep->dir == TX &&
1376 	    !list_empty(&hwep->qh.queue)) {
1377 		spin_unlock_irqrestore(hwep->lock, flags);
1378 		return -EAGAIN;
1379 	}
1380 #endif
1381 
1382 	direction = hwep->dir;
1383 	do {
1384 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
1385 
1386 		if (!value)
1387 			hwep->wedge = 0;
1388 
1389 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1390 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1391 
1392 	} while (hwep->dir != direction);
1393 
1394 	spin_unlock_irqrestore(hwep->lock, flags);
1395 	return retval;
1396 }
1397 
1398 /**
1399  * ep_set_wedge: sets the halt feature and ignores clear requests
1400  *
1401  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1402  */
1403 static int ep_set_wedge(struct usb_ep *ep)
1404 {
1405 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1406 	unsigned long flags;
1407 
1408 	if (ep == NULL || hwep->ep.desc == NULL)
1409 		return -EINVAL;
1410 
1411 	spin_lock_irqsave(hwep->lock, flags);
1412 	hwep->wedge = 1;
1413 	spin_unlock_irqrestore(hwep->lock, flags);
1414 
1415 	return usb_ep_set_halt(ep);
1416 }
1417 
1418 /**
1419  * ep_fifo_flush: flushes contents of a fifo
1420  *
1421  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1422  */
1423 static void ep_fifo_flush(struct usb_ep *ep)
1424 {
1425 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1426 	unsigned long flags;
1427 
1428 	if (ep == NULL) {
1429 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1430 		return;
1431 	}
1432 
1433 	spin_lock_irqsave(hwep->lock, flags);
1434 
1435 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1436 
1437 	spin_unlock_irqrestore(hwep->lock, flags);
1438 }
1439 
1440 /**
1441  * Endpoint-specific part of the API to the USB controller hardware
1442  * Check "usb_gadget.h" for details
1443  */
1444 static const struct usb_ep_ops usb_ep_ops = {
1445 	.enable	       = ep_enable,
1446 	.disable       = ep_disable,
1447 	.alloc_request = ep_alloc_request,
1448 	.free_request  = ep_free_request,
1449 	.queue	       = ep_queue,
1450 	.dequeue       = ep_dequeue,
1451 	.set_halt      = ep_set_halt,
1452 	.set_wedge     = ep_set_wedge,
1453 	.fifo_flush    = ep_fifo_flush,
1454 };
1455 
1456 /******************************************************************************
1457  * GADGET block
1458  *****************************************************************************/
1459 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1460 {
1461 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1462 	unsigned long flags;
1463 	int gadget_ready = 0;
1464 
1465 	spin_lock_irqsave(&ci->lock, flags);
1466 	ci->vbus_active = is_active;
1467 	if (ci->driver)
1468 		gadget_ready = 1;
1469 	spin_unlock_irqrestore(&ci->lock, flags);
1470 
1471 	if (gadget_ready) {
1472 		if (is_active) {
1473 			pm_runtime_get_sync(&_gadget->dev);
1474 			hw_device_reset(ci);
1475 			hw_device_state(ci, ci->ep0out->qh.dma);
1476 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1477 		} else {
1478 			if (ci->driver)
1479 				ci->driver->disconnect(&ci->gadget);
1480 			hw_device_state(ci, 0);
1481 			if (ci->platdata->notify_event)
1482 				ci->platdata->notify_event(ci,
1483 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1484 			_gadget_stop_activity(&ci->gadget);
1485 			pm_runtime_put_sync(&_gadget->dev);
1486 			usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1487 		}
1488 	}
1489 
1490 	return 0;
1491 }
1492 
1493 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1494 {
1495 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1496 	unsigned long flags;
1497 	int ret = 0;
1498 
1499 	spin_lock_irqsave(&ci->lock, flags);
1500 	if (!ci->remote_wakeup) {
1501 		ret = -EOPNOTSUPP;
1502 		goto out;
1503 	}
1504 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1505 		ret = -EINVAL;
1506 		goto out;
1507 	}
1508 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1509 out:
1510 	spin_unlock_irqrestore(&ci->lock, flags);
1511 	return ret;
1512 }
1513 
1514 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1515 {
1516 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1517 
1518 	if (ci->usb_phy)
1519 		return usb_phy_set_power(ci->usb_phy, ma);
1520 	return -ENOTSUPP;
1521 }
1522 
1523 /* Change Data+ pullup status
1524  * this func is used by usb_gadget_connect/disconnet
1525  */
1526 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1527 {
1528 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1529 
1530 	if (!ci->vbus_active)
1531 		return -EOPNOTSUPP;
1532 
1533 	if (is_on)
1534 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1535 	else
1536 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1537 
1538 	return 0;
1539 }
1540 
1541 static int ci_udc_start(struct usb_gadget *gadget,
1542 			 struct usb_gadget_driver *driver);
1543 static int ci_udc_stop(struct usb_gadget *gadget);
1544 /**
1545  * Device operations part of the API to the USB controller hardware,
1546  * which don't involve endpoints (or i/o)
1547  * Check  "usb_gadget.h" for details
1548  */
1549 static const struct usb_gadget_ops usb_gadget_ops = {
1550 	.vbus_session	= ci_udc_vbus_session,
1551 	.wakeup		= ci_udc_wakeup,
1552 	.pullup		= ci_udc_pullup,
1553 	.vbus_draw	= ci_udc_vbus_draw,
1554 	.udc_start	= ci_udc_start,
1555 	.udc_stop	= ci_udc_stop,
1556 };
1557 
1558 static int init_eps(struct ci_hdrc *ci)
1559 {
1560 	int retval = 0, i, j;
1561 
1562 	for (i = 0; i < ci->hw_ep_max/2; i++)
1563 		for (j = RX; j <= TX; j++) {
1564 			int k = i + j * ci->hw_ep_max/2;
1565 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1566 
1567 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1568 					(j == TX)  ? "in" : "out");
1569 
1570 			hwep->ci          = ci;
1571 			hwep->lock         = &ci->lock;
1572 			hwep->td_pool      = ci->td_pool;
1573 
1574 			hwep->ep.name      = hwep->name;
1575 			hwep->ep.ops       = &usb_ep_ops;
1576 			/*
1577 			 * for ep0: maxP defined in desc, for other
1578 			 * eps, maxP is set by epautoconfig() called
1579 			 * by gadget layer
1580 			 */
1581 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1582 
1583 			INIT_LIST_HEAD(&hwep->qh.queue);
1584 			hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1585 						     &hwep->qh.dma);
1586 			if (hwep->qh.ptr == NULL)
1587 				retval = -ENOMEM;
1588 			else
1589 				memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1590 
1591 			/*
1592 			 * set up shorthands for ep0 out and in endpoints,
1593 			 * don't add to gadget's ep_list
1594 			 */
1595 			if (i == 0) {
1596 				if (j == RX)
1597 					ci->ep0out = hwep;
1598 				else
1599 					ci->ep0in = hwep;
1600 
1601 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1602 				continue;
1603 			}
1604 
1605 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1606 		}
1607 
1608 	return retval;
1609 }
1610 
1611 static void destroy_eps(struct ci_hdrc *ci)
1612 {
1613 	int i;
1614 
1615 	for (i = 0; i < ci->hw_ep_max; i++) {
1616 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1617 
1618 		if (hwep->pending_td)
1619 			free_pending_td(hwep);
1620 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1621 	}
1622 }
1623 
1624 /**
1625  * ci_udc_start: register a gadget driver
1626  * @gadget: our gadget
1627  * @driver: the driver being registered
1628  *
1629  * Interrupts are enabled here.
1630  */
1631 static int ci_udc_start(struct usb_gadget *gadget,
1632 			 struct usb_gadget_driver *driver)
1633 {
1634 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1635 	unsigned long flags;
1636 	int retval = -ENOMEM;
1637 
1638 	if (driver->disconnect == NULL)
1639 		return -EINVAL;
1640 
1641 
1642 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1643 	retval = usb_ep_enable(&ci->ep0out->ep);
1644 	if (retval)
1645 		return retval;
1646 
1647 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1648 	retval = usb_ep_enable(&ci->ep0in->ep);
1649 	if (retval)
1650 		return retval;
1651 
1652 	ci->driver = driver;
1653 
1654 	/* Start otg fsm for B-device */
1655 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1656 		ci_hdrc_otg_fsm_start(ci);
1657 		return retval;
1658 	}
1659 
1660 	pm_runtime_get_sync(&ci->gadget.dev);
1661 	if (ci->vbus_active) {
1662 		spin_lock_irqsave(&ci->lock, flags);
1663 		hw_device_reset(ci);
1664 	} else {
1665 		pm_runtime_put_sync(&ci->gadget.dev);
1666 		return retval;
1667 	}
1668 
1669 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1670 	spin_unlock_irqrestore(&ci->lock, flags);
1671 	if (retval)
1672 		pm_runtime_put_sync(&ci->gadget.dev);
1673 
1674 	return retval;
1675 }
1676 
1677 /**
1678  * ci_udc_stop: unregister a gadget driver
1679  */
1680 static int ci_udc_stop(struct usb_gadget *gadget)
1681 {
1682 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1683 	unsigned long flags;
1684 
1685 	spin_lock_irqsave(&ci->lock, flags);
1686 
1687 	if (ci->vbus_active) {
1688 		hw_device_state(ci, 0);
1689 		if (ci->platdata->notify_event)
1690 			ci->platdata->notify_event(ci,
1691 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1692 		spin_unlock_irqrestore(&ci->lock, flags);
1693 		_gadget_stop_activity(&ci->gadget);
1694 		spin_lock_irqsave(&ci->lock, flags);
1695 		pm_runtime_put(&ci->gadget.dev);
1696 	}
1697 
1698 	ci->driver = NULL;
1699 	spin_unlock_irqrestore(&ci->lock, flags);
1700 
1701 	return 0;
1702 }
1703 
1704 /******************************************************************************
1705  * BUS block
1706  *****************************************************************************/
1707 /**
1708  * udc_irq: ci interrupt handler
1709  *
1710  * This function returns IRQ_HANDLED if the IRQ has been handled
1711  * It locks access to registers
1712  */
1713 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1714 {
1715 	irqreturn_t retval;
1716 	u32 intr;
1717 
1718 	if (ci == NULL)
1719 		return IRQ_HANDLED;
1720 
1721 	spin_lock(&ci->lock);
1722 
1723 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1724 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1725 				USBMODE_CM_DC) {
1726 			spin_unlock(&ci->lock);
1727 			return IRQ_NONE;
1728 		}
1729 	}
1730 	intr = hw_test_and_clear_intr_active(ci);
1731 
1732 	if (intr) {
1733 		/* order defines priority - do NOT change it */
1734 		if (USBi_URI & intr)
1735 			isr_reset_handler(ci);
1736 
1737 		if (USBi_PCI & intr) {
1738 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1739 				USB_SPEED_HIGH : USB_SPEED_FULL;
1740 			if (ci->suspended && ci->driver->resume) {
1741 				spin_unlock(&ci->lock);
1742 				ci->driver->resume(&ci->gadget);
1743 				spin_lock(&ci->lock);
1744 				ci->suspended = 0;
1745 			}
1746 		}
1747 
1748 		if (USBi_UI  & intr)
1749 			isr_tr_complete_handler(ci);
1750 
1751 		if (USBi_SLI & intr) {
1752 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1753 			    ci->driver->suspend) {
1754 				ci->suspended = 1;
1755 				spin_unlock(&ci->lock);
1756 				ci->driver->suspend(&ci->gadget);
1757 				usb_gadget_set_state(&ci->gadget,
1758 						USB_STATE_SUSPENDED);
1759 				spin_lock(&ci->lock);
1760 			}
1761 		}
1762 		retval = IRQ_HANDLED;
1763 	} else {
1764 		retval = IRQ_NONE;
1765 	}
1766 	spin_unlock(&ci->lock);
1767 
1768 	return retval;
1769 }
1770 
1771 /**
1772  * udc_start: initialize gadget role
1773  * @ci: chipidea controller
1774  */
1775 static int udc_start(struct ci_hdrc *ci)
1776 {
1777 	struct device *dev = ci->dev;
1778 	int retval = 0;
1779 
1780 	spin_lock_init(&ci->lock);
1781 
1782 	ci->gadget.ops          = &usb_gadget_ops;
1783 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1784 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1785 	ci->gadget.is_otg       = ci->is_otg ? 1 : 0;
1786 	ci->gadget.name         = ci->platdata->name;
1787 
1788 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1789 
1790 	/* alloc resources */
1791 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1792 				       sizeof(struct ci_hw_qh),
1793 				       64, CI_HDRC_PAGE_SIZE);
1794 	if (ci->qh_pool == NULL)
1795 		return -ENOMEM;
1796 
1797 	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1798 				       sizeof(struct ci_hw_td),
1799 				       64, CI_HDRC_PAGE_SIZE);
1800 	if (ci->td_pool == NULL) {
1801 		retval = -ENOMEM;
1802 		goto free_qh_pool;
1803 	}
1804 
1805 	retval = init_eps(ci);
1806 	if (retval)
1807 		goto free_pools;
1808 
1809 	ci->gadget.ep0 = &ci->ep0in->ep;
1810 
1811 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1812 	if (retval)
1813 		goto destroy_eps;
1814 
1815 	pm_runtime_no_callbacks(&ci->gadget.dev);
1816 	pm_runtime_enable(&ci->gadget.dev);
1817 
1818 	return retval;
1819 
1820 destroy_eps:
1821 	destroy_eps(ci);
1822 free_pools:
1823 	dma_pool_destroy(ci->td_pool);
1824 free_qh_pool:
1825 	dma_pool_destroy(ci->qh_pool);
1826 	return retval;
1827 }
1828 
1829 /**
1830  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1831  *
1832  * No interrupts active, the IRQ has been released
1833  */
1834 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1835 {
1836 	if (!ci->roles[CI_ROLE_GADGET])
1837 		return;
1838 
1839 	usb_del_gadget_udc(&ci->gadget);
1840 
1841 	destroy_eps(ci);
1842 
1843 	dma_pool_destroy(ci->td_pool);
1844 	dma_pool_destroy(ci->qh_pool);
1845 }
1846 
1847 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1848 {
1849 	if (ci->is_otg)
1850 		/* Clear and enable BSV irq */
1851 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
1852 					OTGSC_BSVIS | OTGSC_BSVIE);
1853 
1854 	return 0;
1855 }
1856 
1857 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1858 {
1859 	/*
1860 	 * host doesn't care B_SESSION_VALID event
1861 	 * so clear and disbale BSV irq
1862 	 */
1863 	if (ci->is_otg)
1864 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
1865 }
1866 
1867 /**
1868  * ci_hdrc_gadget_init - initialize device related bits
1869  * ci: the controller
1870  *
1871  * This function initializes the gadget, if the device is "device capable".
1872  */
1873 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1874 {
1875 	struct ci_role_driver *rdrv;
1876 
1877 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1878 		return -ENXIO;
1879 
1880 	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1881 	if (!rdrv)
1882 		return -ENOMEM;
1883 
1884 	rdrv->start	= udc_id_switch_for_device;
1885 	rdrv->stop	= udc_id_switch_for_host;
1886 	rdrv->irq	= udc_irq;
1887 	rdrv->name	= "gadget";
1888 	ci->roles[CI_ROLE_GADGET] = rdrv;
1889 
1890 	return udc_start(ci);
1891 }
1892