xref: /linux/drivers/usb/chipidea/udc.c (revision 3c4fc7bf4c9e66fe71abcbf93f62f4ddb89b7f15)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * udc.c - ChipIdea UDC driver
4  *
5  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
6  *
7  * Author: David Lopo
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/dmapool.h>
13 #include <linux/err.h>
14 #include <linux/irqreturn.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/pinctrl/consumer.h>
19 #include <linux/usb/ch9.h>
20 #include <linux/usb/gadget.h>
21 #include <linux/usb/otg-fsm.h>
22 #include <linux/usb/chipidea.h>
23 
24 #include "ci.h"
25 #include "udc.h"
26 #include "bits.h"
27 #include "otg.h"
28 #include "otg_fsm.h"
29 #include "trace.h"
30 
31 /* control endpoint description */
32 static const struct usb_endpoint_descriptor
33 ctrl_endpt_out_desc = {
34 	.bLength         = USB_DT_ENDPOINT_SIZE,
35 	.bDescriptorType = USB_DT_ENDPOINT,
36 
37 	.bEndpointAddress = USB_DIR_OUT,
38 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
39 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
40 };
41 
42 static const struct usb_endpoint_descriptor
43 ctrl_endpt_in_desc = {
44 	.bLength         = USB_DT_ENDPOINT_SIZE,
45 	.bDescriptorType = USB_DT_ENDPOINT,
46 
47 	.bEndpointAddress = USB_DIR_IN,
48 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
49 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
50 };
51 
52 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
53 		       struct td_node *node);
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 == TX) ? 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  * @ci: the controller
79  * @dma: 0 => disable, !0 => enable and set dma engine
80  *
81  * This function returns an error code
82  */
83 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
84 {
85 	if (dma) {
86 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
87 		/* interrupt, error, port change, reset, sleep/suspend */
88 		hw_write(ci, OP_USBINTR, ~0,
89 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
90 	} else {
91 		hw_write(ci, OP_USBINTR, ~0, 0);
92 	}
93 	return 0;
94 }
95 
96 /**
97  * hw_ep_flush: flush endpoint fifo (execute without interruption)
98  * @ci: the controller
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  * @ci: the controller
121  * @num: endpoint number
122  * @dir: endpoint direction
123  *
124  * This function returns an error code
125  */
126 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
127 {
128 	hw_write(ci, OP_ENDPTCTRL + num,
129 		 (dir == TX) ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
130 	return 0;
131 }
132 
133 /**
134  * hw_ep_enable: enables endpoint (execute without interruption)
135  * @ci: the controller
136  * @num:  endpoint number
137  * @dir:  endpoint direction
138  * @type: endpoint type
139  *
140  * This function returns an error code
141  */
142 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
143 {
144 	u32 mask, data;
145 
146 	if (dir == TX) {
147 		mask  = ENDPTCTRL_TXT;  /* type    */
148 		data  = type << __ffs(mask);
149 
150 		mask |= ENDPTCTRL_TXS;  /* unstall */
151 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
152 		data |= ENDPTCTRL_TXR;
153 		mask |= ENDPTCTRL_TXE;  /* enable  */
154 		data |= ENDPTCTRL_TXE;
155 	} else {
156 		mask  = ENDPTCTRL_RXT;  /* type    */
157 		data  = type << __ffs(mask);
158 
159 		mask |= ENDPTCTRL_RXS;  /* unstall */
160 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
161 		data |= ENDPTCTRL_RXR;
162 		mask |= ENDPTCTRL_RXE;  /* enable  */
163 		data |= ENDPTCTRL_RXE;
164 	}
165 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
166 	return 0;
167 }
168 
169 /**
170  * hw_ep_get_halt: return endpoint halt status
171  * @ci: the controller
172  * @num: endpoint number
173  * @dir: endpoint direction
174  *
175  * This function returns 1 if endpoint halted
176  */
177 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
178 {
179 	u32 mask = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
180 
181 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
182 }
183 
184 /**
185  * hw_ep_prime: primes endpoint (execute without interruption)
186  * @ci: the controller
187  * @num:     endpoint number
188  * @dir:     endpoint direction
189  * @is_ctrl: true if control endpoint
190  *
191  * This function returns an error code
192  */
193 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
194 {
195 	int n = hw_ep_bit(num, dir);
196 
197 	/* Synchronize before ep prime */
198 	wmb();
199 
200 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
201 		return -EAGAIN;
202 
203 	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
204 
205 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
206 		cpu_relax();
207 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
208 		return -EAGAIN;
209 
210 	/* status shoult be tested according with manual but it doesn't work */
211 	return 0;
212 }
213 
214 /**
215  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
216  *                 without interruption)
217  * @ci: the controller
218  * @num:   endpoint number
219  * @dir:   endpoint direction
220  * @value: true => stall, false => unstall
221  *
222  * This function returns an error code
223  */
224 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
225 {
226 	if (value != 0 && value != 1)
227 		return -EINVAL;
228 
229 	do {
230 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
231 		u32 mask_xs = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
232 		u32 mask_xr = (dir == TX) ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
233 
234 		/* data toggle - reserved for EP0 but it's in ESS */
235 		hw_write(ci, reg, mask_xs|mask_xr,
236 			  value ? mask_xs : mask_xr);
237 	} while (value != hw_ep_get_halt(ci, num, dir));
238 
239 	return 0;
240 }
241 
242 /**
243  * hw_port_is_high_speed: test if port is high speed
244  * @ci: the controller
245  *
246  * This function returns true if high speed port
247  */
248 static int hw_port_is_high_speed(struct ci_hdrc *ci)
249 {
250 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
251 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
252 }
253 
254 /**
255  * hw_test_and_clear_complete: test & clear complete status (execute without
256  *                             interruption)
257  * @ci: the controller
258  * @n: endpoint number
259  *
260  * This function returns complete status
261  */
262 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
263 {
264 	n = ep_to_bit(ci, n);
265 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
266 }
267 
268 /**
269  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
270  *                                without interruption)
271  * @ci: the controller
272  *
273  * This function returns active interrutps
274  */
275 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
276 {
277 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
278 
279 	hw_write(ci, OP_USBSTS, ~0, reg);
280 	return reg;
281 }
282 
283 /**
284  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
285  *                                interruption)
286  * @ci: the controller
287  *
288  * This function returns guard value
289  */
290 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
291 {
292 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
293 }
294 
295 /**
296  * hw_test_and_set_setup_guard: test & set setup guard (execute without
297  *                              interruption)
298  * @ci: the controller
299  *
300  * This function returns guard value
301  */
302 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
303 {
304 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
305 }
306 
307 /**
308  * hw_usb_set_address: configures USB address (execute without interruption)
309  * @ci: the controller
310  * @value: new USB address
311  *
312  * This function explicitly sets the address, without the "USBADRA" (advance)
313  * feature, which is not supported by older versions of the controller.
314  */
315 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
316 {
317 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
318 		 value << __ffs(DEVICEADDR_USBADR));
319 }
320 
321 /**
322  * hw_usb_reset: restart device after a bus reset (execute without
323  *               interruption)
324  * @ci: the controller
325  *
326  * This function returns an error code
327  */
328 static int hw_usb_reset(struct ci_hdrc *ci)
329 {
330 	hw_usb_set_address(ci, 0);
331 
332 	/* ESS flushes only at end?!? */
333 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
334 
335 	/* clear setup token semaphores */
336 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
337 
338 	/* clear complete status */
339 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
340 
341 	/* wait until all bits cleared */
342 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
343 		udelay(10);             /* not RTOS friendly */
344 
345 	/* reset all endpoints ? */
346 
347 	/* reset internal status and wait for further instructions
348 	   no need to verify the port reset status (ESS does it) */
349 
350 	return 0;
351 }
352 
353 /******************************************************************************
354  * UTIL block
355  *****************************************************************************/
356 
357 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
358 			unsigned int length, struct scatterlist *s)
359 {
360 	int i;
361 	u32 temp;
362 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
363 						  GFP_ATOMIC);
364 
365 	if (node == NULL)
366 		return -ENOMEM;
367 
368 	node->ptr = dma_pool_zalloc(hwep->td_pool, GFP_ATOMIC, &node->dma);
369 	if (node->ptr == NULL) {
370 		kfree(node);
371 		return -ENOMEM;
372 	}
373 
374 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
375 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
376 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
377 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
378 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
379 
380 		if (hwreq->req.length == 0
381 				|| hwreq->req.length % hwep->ep.maxpacket)
382 			mul++;
383 		node->ptr->token |= cpu_to_le32(mul << __ffs(TD_MULTO));
384 	}
385 
386 	if (s) {
387 		temp = (u32) (sg_dma_address(s) + hwreq->req.actual);
388 		node->td_remaining_size = CI_MAX_BUF_SIZE - length;
389 	} else {
390 		temp = (u32) (hwreq->req.dma + hwreq->req.actual);
391 	}
392 
393 	if (length) {
394 		node->ptr->page[0] = cpu_to_le32(temp);
395 		for (i = 1; i < TD_PAGE_COUNT; i++) {
396 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
397 			page &= ~TD_RESERVED_MASK;
398 			node->ptr->page[i] = cpu_to_le32(page);
399 		}
400 	}
401 
402 	hwreq->req.actual += length;
403 
404 	if (!list_empty(&hwreq->tds)) {
405 		/* get the last entry */
406 		lastnode = list_entry(hwreq->tds.prev,
407 				struct td_node, td);
408 		lastnode->ptr->next = cpu_to_le32(node->dma);
409 	}
410 
411 	INIT_LIST_HEAD(&node->td);
412 	list_add_tail(&node->td, &hwreq->tds);
413 
414 	return 0;
415 }
416 
417 /**
418  * _usb_addr: calculates endpoint address from direction & number
419  * @ep:  endpoint
420  */
421 static inline u8 _usb_addr(struct ci_hw_ep *ep)
422 {
423 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
424 }
425 
426 static int prepare_td_for_non_sg(struct ci_hw_ep *hwep,
427 		struct ci_hw_req *hwreq)
428 {
429 	unsigned int rest = hwreq->req.length;
430 	int pages = TD_PAGE_COUNT;
431 	int ret = 0;
432 
433 	if (rest == 0) {
434 		ret = add_td_to_list(hwep, hwreq, 0, NULL);
435 		if (ret < 0)
436 			return ret;
437 	}
438 
439 	/*
440 	 * The first buffer could be not page aligned.
441 	 * In that case we have to span into one extra td.
442 	 */
443 	if (hwreq->req.dma % PAGE_SIZE)
444 		pages--;
445 
446 	while (rest > 0) {
447 		unsigned int count = min(hwreq->req.length - hwreq->req.actual,
448 			(unsigned int)(pages * CI_HDRC_PAGE_SIZE));
449 
450 		ret = add_td_to_list(hwep, hwreq, count, NULL);
451 		if (ret < 0)
452 			return ret;
453 
454 		rest -= count;
455 	}
456 
457 	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
458 	    && (hwreq->req.length % hwep->ep.maxpacket == 0)) {
459 		ret = add_td_to_list(hwep, hwreq, 0, NULL);
460 		if (ret < 0)
461 			return ret;
462 	}
463 
464 	return ret;
465 }
466 
467 static int prepare_td_per_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
468 		struct scatterlist *s)
469 {
470 	unsigned int rest = sg_dma_len(s);
471 	int ret = 0;
472 
473 	hwreq->req.actual = 0;
474 	while (rest > 0) {
475 		unsigned int count = min_t(unsigned int, rest,
476 				CI_MAX_BUF_SIZE);
477 
478 		ret = add_td_to_list(hwep, hwreq, count, s);
479 		if (ret < 0)
480 			return ret;
481 
482 		rest -= count;
483 	}
484 
485 	return ret;
486 }
487 
488 static void ci_add_buffer_entry(struct td_node *node, struct scatterlist *s)
489 {
490 	int empty_td_slot_index = (CI_MAX_BUF_SIZE - node->td_remaining_size)
491 			/ CI_HDRC_PAGE_SIZE;
492 	int i;
493 	u32 token;
494 
495 	token = le32_to_cpu(node->ptr->token) + (sg_dma_len(s) << __ffs(TD_TOTAL_BYTES));
496 	node->ptr->token = cpu_to_le32(token);
497 
498 	for (i = empty_td_slot_index; i < TD_PAGE_COUNT; i++) {
499 		u32 page = (u32) sg_dma_address(s) +
500 			(i - empty_td_slot_index) * CI_HDRC_PAGE_SIZE;
501 
502 		page &= ~TD_RESERVED_MASK;
503 		node->ptr->page[i] = cpu_to_le32(page);
504 	}
505 }
506 
507 static int prepare_td_for_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
508 {
509 	struct usb_request *req = &hwreq->req;
510 	struct scatterlist *s = req->sg;
511 	int ret = 0, i = 0;
512 	struct td_node *node = NULL;
513 
514 	if (!s || req->zero || req->length == 0) {
515 		dev_err(hwep->ci->dev, "not supported operation for sg\n");
516 		return -EINVAL;
517 	}
518 
519 	while (i++ < req->num_mapped_sgs) {
520 		if (sg_dma_address(s) % PAGE_SIZE) {
521 			dev_err(hwep->ci->dev, "not page aligned sg buffer\n");
522 			return -EINVAL;
523 		}
524 
525 		if (node && (node->td_remaining_size >= sg_dma_len(s))) {
526 			ci_add_buffer_entry(node, s);
527 			node->td_remaining_size -= sg_dma_len(s);
528 		} else {
529 			ret = prepare_td_per_sg(hwep, hwreq, s);
530 			if (ret)
531 				return ret;
532 
533 			node = list_entry(hwreq->tds.prev,
534 				struct td_node, td);
535 		}
536 
537 		s = sg_next(s);
538 	}
539 
540 	return ret;
541 }
542 
543 /**
544  * _hardware_enqueue: configures a request at hardware level
545  * @hwep:   endpoint
546  * @hwreq:  request
547  *
548  * This function returns an error code
549  */
550 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
551 {
552 	struct ci_hdrc *ci = hwep->ci;
553 	int ret = 0;
554 	struct td_node *firstnode, *lastnode;
555 
556 	/* don't queue twice */
557 	if (hwreq->req.status == -EALREADY)
558 		return -EALREADY;
559 
560 	hwreq->req.status = -EALREADY;
561 
562 	ret = usb_gadget_map_request_by_dev(ci->dev->parent,
563 					    &hwreq->req, hwep->dir);
564 	if (ret)
565 		return ret;
566 
567 	if (hwreq->req.num_mapped_sgs)
568 		ret = prepare_td_for_sg(hwep, hwreq);
569 	else
570 		ret = prepare_td_for_non_sg(hwep, hwreq);
571 
572 	if (ret)
573 		return ret;
574 
575 	lastnode = list_entry(hwreq->tds.prev,
576 		struct td_node, td);
577 
578 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
579 	if (!hwreq->req.no_interrupt)
580 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
581 
582 	list_for_each_entry_safe(firstnode, lastnode, &hwreq->tds, td)
583 		trace_ci_prepare_td(hwep, hwreq, firstnode);
584 
585 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
586 
587 	wmb();
588 
589 	hwreq->req.actual = 0;
590 	if (!list_empty(&hwep->qh.queue)) {
591 		struct ci_hw_req *hwreqprev;
592 		int n = hw_ep_bit(hwep->num, hwep->dir);
593 		int tmp_stat;
594 		struct td_node *prevlastnode;
595 		u32 next = firstnode->dma & TD_ADDR_MASK;
596 
597 		hwreqprev = list_entry(hwep->qh.queue.prev,
598 				struct ci_hw_req, queue);
599 		prevlastnode = list_entry(hwreqprev->tds.prev,
600 				struct td_node, td);
601 
602 		prevlastnode->ptr->next = cpu_to_le32(next);
603 		wmb();
604 
605 		if (ci->rev == CI_REVISION_22) {
606 			if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
607 				reprime_dtd(ci, hwep, prevlastnode);
608 		}
609 
610 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
611 			goto done;
612 		do {
613 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
614 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
615 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
616 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
617 		if (tmp_stat)
618 			goto done;
619 	}
620 
621 	/*  QH configuration */
622 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
623 	hwep->qh.ptr->td.token &=
624 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
625 
626 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
627 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
628 
629 		if (hwreq->req.length == 0
630 				|| hwreq->req.length % hwep->ep.maxpacket)
631 			mul++;
632 		hwep->qh.ptr->cap |= cpu_to_le32(mul << __ffs(QH_MULT));
633 	}
634 
635 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
636 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
637 done:
638 	return ret;
639 }
640 
641 /**
642  * free_pending_td: remove a pending request for the endpoint
643  * @hwep: endpoint
644  */
645 static void free_pending_td(struct ci_hw_ep *hwep)
646 {
647 	struct td_node *pending = hwep->pending_td;
648 
649 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
650 	hwep->pending_td = NULL;
651 	kfree(pending);
652 }
653 
654 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
655 					   struct td_node *node)
656 {
657 	hwep->qh.ptr->td.next = cpu_to_le32(node->dma);
658 	hwep->qh.ptr->td.token &=
659 		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
660 
661 	return hw_ep_prime(ci, hwep->num, hwep->dir,
662 				hwep->type == USB_ENDPOINT_XFER_CONTROL);
663 }
664 
665 /**
666  * _hardware_dequeue: handles a request at hardware level
667  * @hwep: endpoint
668  * @hwreq:  request
669  *
670  * This function returns an error code
671  */
672 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
673 {
674 	u32 tmptoken;
675 	struct td_node *node, *tmpnode;
676 	unsigned remaining_length;
677 	unsigned actual = hwreq->req.length;
678 	struct ci_hdrc *ci = hwep->ci;
679 
680 	if (hwreq->req.status != -EALREADY)
681 		return -EINVAL;
682 
683 	hwreq->req.status = 0;
684 
685 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
686 		tmptoken = le32_to_cpu(node->ptr->token);
687 		trace_ci_complete_td(hwep, hwreq, node);
688 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
689 			int n = hw_ep_bit(hwep->num, hwep->dir);
690 
691 			if (ci->rev == CI_REVISION_24)
692 				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
693 					reprime_dtd(ci, hwep, node);
694 			hwreq->req.status = -EALREADY;
695 			return -EBUSY;
696 		}
697 
698 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
699 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
700 		actual -= remaining_length;
701 
702 		hwreq->req.status = tmptoken & TD_STATUS;
703 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
704 			hwreq->req.status = -EPIPE;
705 			break;
706 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
707 			hwreq->req.status = -EPROTO;
708 			break;
709 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
710 			hwreq->req.status = -EILSEQ;
711 			break;
712 		}
713 
714 		if (remaining_length) {
715 			if (hwep->dir == TX) {
716 				hwreq->req.status = -EPROTO;
717 				break;
718 			}
719 		}
720 		/*
721 		 * As the hardware could still address the freed td
722 		 * which will run the udc unusable, the cleanup of the
723 		 * td has to be delayed by one.
724 		 */
725 		if (hwep->pending_td)
726 			free_pending_td(hwep);
727 
728 		hwep->pending_td = node;
729 		list_del_init(&node->td);
730 	}
731 
732 	usb_gadget_unmap_request_by_dev(hwep->ci->dev->parent,
733 					&hwreq->req, hwep->dir);
734 
735 	hwreq->req.actual += actual;
736 
737 	if (hwreq->req.status)
738 		return hwreq->req.status;
739 
740 	return hwreq->req.actual;
741 }
742 
743 /**
744  * _ep_nuke: dequeues all endpoint requests
745  * @hwep: endpoint
746  *
747  * This function returns an error code
748  * Caller must hold lock
749  */
750 static int _ep_nuke(struct ci_hw_ep *hwep)
751 __releases(hwep->lock)
752 __acquires(hwep->lock)
753 {
754 	struct td_node *node, *tmpnode;
755 	if (hwep == NULL)
756 		return -EINVAL;
757 
758 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
759 
760 	while (!list_empty(&hwep->qh.queue)) {
761 
762 		/* pop oldest request */
763 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
764 						     struct ci_hw_req, queue);
765 
766 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
767 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
768 			list_del_init(&node->td);
769 			node->ptr = NULL;
770 			kfree(node);
771 		}
772 
773 		list_del_init(&hwreq->queue);
774 		hwreq->req.status = -ESHUTDOWN;
775 
776 		if (hwreq->req.complete != NULL) {
777 			spin_unlock(hwep->lock);
778 			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
779 			spin_lock(hwep->lock);
780 		}
781 	}
782 
783 	if (hwep->pending_td)
784 		free_pending_td(hwep);
785 
786 	return 0;
787 }
788 
789 static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
790 {
791 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
792 	int direction, retval = 0;
793 	unsigned long flags;
794 
795 	if (ep == NULL || hwep->ep.desc == NULL)
796 		return -EINVAL;
797 
798 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
799 		return -EOPNOTSUPP;
800 
801 	spin_lock_irqsave(hwep->lock, flags);
802 
803 	if (value && hwep->dir == TX && check_transfer &&
804 		!list_empty(&hwep->qh.queue) &&
805 			!usb_endpoint_xfer_control(hwep->ep.desc)) {
806 		spin_unlock_irqrestore(hwep->lock, flags);
807 		return -EAGAIN;
808 	}
809 
810 	direction = hwep->dir;
811 	do {
812 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
813 
814 		if (!value)
815 			hwep->wedge = 0;
816 
817 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
818 			hwep->dir = (hwep->dir == TX) ? RX : TX;
819 
820 	} while (hwep->dir != direction);
821 
822 	spin_unlock_irqrestore(hwep->lock, flags);
823 	return retval;
824 }
825 
826 
827 /**
828  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
829  * @gadget: gadget
830  *
831  * This function returns an error code
832  */
833 static int _gadget_stop_activity(struct usb_gadget *gadget)
834 {
835 	struct usb_ep *ep;
836 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
837 	unsigned long flags;
838 
839 	/* flush all endpoints */
840 	gadget_for_each_ep(ep, gadget) {
841 		usb_ep_fifo_flush(ep);
842 	}
843 	usb_ep_fifo_flush(&ci->ep0out->ep);
844 	usb_ep_fifo_flush(&ci->ep0in->ep);
845 
846 	/* make sure to disable all endpoints */
847 	gadget_for_each_ep(ep, gadget) {
848 		usb_ep_disable(ep);
849 	}
850 
851 	if (ci->status != NULL) {
852 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
853 		ci->status = NULL;
854 	}
855 
856 	spin_lock_irqsave(&ci->lock, flags);
857 	ci->gadget.speed = USB_SPEED_UNKNOWN;
858 	ci->remote_wakeup = 0;
859 	ci->suspended = 0;
860 	spin_unlock_irqrestore(&ci->lock, flags);
861 
862 	return 0;
863 }
864 
865 /******************************************************************************
866  * ISR block
867  *****************************************************************************/
868 /**
869  * isr_reset_handler: USB reset interrupt handler
870  * @ci: UDC device
871  *
872  * This function resets USB engine after a bus reset occurred
873  */
874 static void isr_reset_handler(struct ci_hdrc *ci)
875 __releases(ci->lock)
876 __acquires(ci->lock)
877 {
878 	int retval;
879 
880 	spin_unlock(&ci->lock);
881 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
882 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
883 
884 	retval = _gadget_stop_activity(&ci->gadget);
885 	if (retval)
886 		goto done;
887 
888 	retval = hw_usb_reset(ci);
889 	if (retval)
890 		goto done;
891 
892 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
893 	if (ci->status == NULL)
894 		retval = -ENOMEM;
895 
896 done:
897 	spin_lock(&ci->lock);
898 
899 	if (retval)
900 		dev_err(ci->dev, "error: %i\n", retval);
901 }
902 
903 /**
904  * isr_get_status_complete: get_status request complete function
905  * @ep:  endpoint
906  * @req: request handled
907  *
908  * Caller must release lock
909  */
910 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
911 {
912 	if (ep == NULL || req == NULL)
913 		return;
914 
915 	kfree(req->buf);
916 	usb_ep_free_request(ep, req);
917 }
918 
919 /**
920  * _ep_queue: queues (submits) an I/O request to an endpoint
921  * @ep:        endpoint
922  * @req:       request
923  * @gfp_flags: GFP flags (not used)
924  *
925  * Caller must hold lock
926  * This function returns an error code
927  */
928 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
929 		    gfp_t __maybe_unused gfp_flags)
930 {
931 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
932 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
933 	struct ci_hdrc *ci = hwep->ci;
934 	int retval = 0;
935 
936 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
937 		return -EINVAL;
938 
939 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
940 		if (req->length)
941 			hwep = (ci->ep0_dir == RX) ?
942 			       ci->ep0out : ci->ep0in;
943 		if (!list_empty(&hwep->qh.queue)) {
944 			_ep_nuke(hwep);
945 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
946 				 _usb_addr(hwep));
947 		}
948 	}
949 
950 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
951 	    hwreq->req.length > hwep->ep.mult * hwep->ep.maxpacket) {
952 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
953 		return -EMSGSIZE;
954 	}
955 
956 	/* first nuke then test link, e.g. previous status has not sent */
957 	if (!list_empty(&hwreq->queue)) {
958 		dev_err(hwep->ci->dev, "request already in queue\n");
959 		return -EBUSY;
960 	}
961 
962 	/* push request */
963 	hwreq->req.status = -EINPROGRESS;
964 	hwreq->req.actual = 0;
965 
966 	retval = _hardware_enqueue(hwep, hwreq);
967 
968 	if (retval == -EALREADY)
969 		retval = 0;
970 	if (!retval)
971 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
972 
973 	return retval;
974 }
975 
976 /**
977  * isr_get_status_response: get_status request response
978  * @ci: ci struct
979  * @setup: setup request packet
980  *
981  * This function returns an error code
982  */
983 static int isr_get_status_response(struct ci_hdrc *ci,
984 				   struct usb_ctrlrequest *setup)
985 __releases(hwep->lock)
986 __acquires(hwep->lock)
987 {
988 	struct ci_hw_ep *hwep = ci->ep0in;
989 	struct usb_request *req = NULL;
990 	gfp_t gfp_flags = GFP_ATOMIC;
991 	int dir, num, retval;
992 
993 	if (hwep == NULL || setup == NULL)
994 		return -EINVAL;
995 
996 	spin_unlock(hwep->lock);
997 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
998 	spin_lock(hwep->lock);
999 	if (req == NULL)
1000 		return -ENOMEM;
1001 
1002 	req->complete = isr_get_status_complete;
1003 	req->length   = 2;
1004 	req->buf      = kzalloc(req->length, gfp_flags);
1005 	if (req->buf == NULL) {
1006 		retval = -ENOMEM;
1007 		goto err_free_req;
1008 	}
1009 
1010 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
1011 		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
1012 			ci->gadget.is_selfpowered;
1013 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
1014 		   == USB_RECIP_ENDPOINT) {
1015 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
1016 			TX : RX;
1017 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
1018 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
1019 	}
1020 	/* else do nothing; reserved for future use */
1021 
1022 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
1023 	if (retval)
1024 		goto err_free_buf;
1025 
1026 	return 0;
1027 
1028  err_free_buf:
1029 	kfree(req->buf);
1030  err_free_req:
1031 	spin_unlock(hwep->lock);
1032 	usb_ep_free_request(&hwep->ep, req);
1033 	spin_lock(hwep->lock);
1034 	return retval;
1035 }
1036 
1037 /**
1038  * isr_setup_status_complete: setup_status request complete function
1039  * @ep:  endpoint
1040  * @req: request handled
1041  *
1042  * Caller must release lock. Put the port in test mode if test mode
1043  * feature is selected.
1044  */
1045 static void
1046 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
1047 {
1048 	struct ci_hdrc *ci = req->context;
1049 	unsigned long flags;
1050 
1051 	if (req->status < 0)
1052 		return;
1053 
1054 	if (ci->setaddr) {
1055 		hw_usb_set_address(ci, ci->address);
1056 		ci->setaddr = false;
1057 		if (ci->address)
1058 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
1059 	}
1060 
1061 	spin_lock_irqsave(&ci->lock, flags);
1062 	if (ci->test_mode)
1063 		hw_port_test_set(ci, ci->test_mode);
1064 	spin_unlock_irqrestore(&ci->lock, flags);
1065 }
1066 
1067 /**
1068  * isr_setup_status_phase: queues the status phase of a setup transation
1069  * @ci: ci struct
1070  *
1071  * This function returns an error code
1072  */
1073 static int isr_setup_status_phase(struct ci_hdrc *ci)
1074 {
1075 	struct ci_hw_ep *hwep;
1076 
1077 	/*
1078 	 * Unexpected USB controller behavior, caused by bad signal integrity
1079 	 * or ground reference problems, can lead to isr_setup_status_phase
1080 	 * being called with ci->status equal to NULL.
1081 	 * If this situation occurs, you should review your USB hardware design.
1082 	 */
1083 	if (WARN_ON_ONCE(!ci->status))
1084 		return -EPIPE;
1085 
1086 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
1087 	ci->status->context = ci;
1088 	ci->status->complete = isr_setup_status_complete;
1089 
1090 	return _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
1091 }
1092 
1093 /**
1094  * isr_tr_complete_low: transaction complete low level handler
1095  * @hwep: endpoint
1096  *
1097  * This function returns an error code
1098  * Caller must hold lock
1099  */
1100 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
1101 __releases(hwep->lock)
1102 __acquires(hwep->lock)
1103 {
1104 	struct ci_hw_req *hwreq, *hwreqtemp;
1105 	struct ci_hw_ep *hweptemp = hwep;
1106 	int retval = 0;
1107 
1108 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
1109 			queue) {
1110 		retval = _hardware_dequeue(hwep, hwreq);
1111 		if (retval < 0)
1112 			break;
1113 		list_del_init(&hwreq->queue);
1114 		if (hwreq->req.complete != NULL) {
1115 			spin_unlock(hwep->lock);
1116 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
1117 					hwreq->req.length)
1118 				hweptemp = hwep->ci->ep0in;
1119 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
1120 			spin_lock(hwep->lock);
1121 		}
1122 	}
1123 
1124 	if (retval == -EBUSY)
1125 		retval = 0;
1126 
1127 	return retval;
1128 }
1129 
1130 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
1131 {
1132 	dev_warn(&ci->gadget.dev,
1133 		"connect the device to an alternate port if you want HNP\n");
1134 	return isr_setup_status_phase(ci);
1135 }
1136 
1137 /**
1138  * isr_setup_packet_handler: setup packet handler
1139  * @ci: UDC descriptor
1140  *
1141  * This function handles setup packet
1142  */
1143 static void isr_setup_packet_handler(struct ci_hdrc *ci)
1144 __releases(ci->lock)
1145 __acquires(ci->lock)
1146 {
1147 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1148 	struct usb_ctrlrequest req;
1149 	int type, num, dir, err = -EINVAL;
1150 	u8 tmode = 0;
1151 
1152 	/*
1153 	 * Flush data and handshake transactions of previous
1154 	 * setup packet.
1155 	 */
1156 	_ep_nuke(ci->ep0out);
1157 	_ep_nuke(ci->ep0in);
1158 
1159 	/* read_setup_packet */
1160 	do {
1161 		hw_test_and_set_setup_guard(ci);
1162 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1163 	} while (!hw_test_and_clear_setup_guard(ci));
1164 
1165 	type = req.bRequestType;
1166 
1167 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1168 
1169 	switch (req.bRequest) {
1170 	case USB_REQ_CLEAR_FEATURE:
1171 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1172 				le16_to_cpu(req.wValue) ==
1173 				USB_ENDPOINT_HALT) {
1174 			if (req.wLength != 0)
1175 				break;
1176 			num  = le16_to_cpu(req.wIndex);
1177 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1178 			num &= USB_ENDPOINT_NUMBER_MASK;
1179 			if (dir == TX)
1180 				num += ci->hw_ep_max / 2;
1181 			if (!ci->ci_hw_ep[num].wedge) {
1182 				spin_unlock(&ci->lock);
1183 				err = usb_ep_clear_halt(
1184 					&ci->ci_hw_ep[num].ep);
1185 				spin_lock(&ci->lock);
1186 				if (err)
1187 					break;
1188 			}
1189 			err = isr_setup_status_phase(ci);
1190 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1191 				le16_to_cpu(req.wValue) ==
1192 				USB_DEVICE_REMOTE_WAKEUP) {
1193 			if (req.wLength != 0)
1194 				break;
1195 			ci->remote_wakeup = 0;
1196 			err = isr_setup_status_phase(ci);
1197 		} else {
1198 			goto delegate;
1199 		}
1200 		break;
1201 	case USB_REQ_GET_STATUS:
1202 		if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
1203 			le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
1204 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1205 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1206 			goto delegate;
1207 		if (le16_to_cpu(req.wLength) != 2 ||
1208 		    le16_to_cpu(req.wValue)  != 0)
1209 			break;
1210 		err = isr_get_status_response(ci, &req);
1211 		break;
1212 	case USB_REQ_SET_ADDRESS:
1213 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1214 			goto delegate;
1215 		if (le16_to_cpu(req.wLength) != 0 ||
1216 		    le16_to_cpu(req.wIndex)  != 0)
1217 			break;
1218 		ci->address = (u8)le16_to_cpu(req.wValue);
1219 		ci->setaddr = true;
1220 		err = isr_setup_status_phase(ci);
1221 		break;
1222 	case USB_REQ_SET_FEATURE:
1223 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1224 				le16_to_cpu(req.wValue) ==
1225 				USB_ENDPOINT_HALT) {
1226 			if (req.wLength != 0)
1227 				break;
1228 			num  = le16_to_cpu(req.wIndex);
1229 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1230 			num &= USB_ENDPOINT_NUMBER_MASK;
1231 			if (dir == TX)
1232 				num += ci->hw_ep_max / 2;
1233 
1234 			spin_unlock(&ci->lock);
1235 			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1236 			spin_lock(&ci->lock);
1237 			if (!err)
1238 				isr_setup_status_phase(ci);
1239 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1240 			if (req.wLength != 0)
1241 				break;
1242 			switch (le16_to_cpu(req.wValue)) {
1243 			case USB_DEVICE_REMOTE_WAKEUP:
1244 				ci->remote_wakeup = 1;
1245 				err = isr_setup_status_phase(ci);
1246 				break;
1247 			case USB_DEVICE_TEST_MODE:
1248 				tmode = le16_to_cpu(req.wIndex) >> 8;
1249 				switch (tmode) {
1250 				case USB_TEST_J:
1251 				case USB_TEST_K:
1252 				case USB_TEST_SE0_NAK:
1253 				case USB_TEST_PACKET:
1254 				case USB_TEST_FORCE_ENABLE:
1255 					ci->test_mode = tmode;
1256 					err = isr_setup_status_phase(
1257 							ci);
1258 					break;
1259 				default:
1260 					break;
1261 				}
1262 				break;
1263 			case USB_DEVICE_B_HNP_ENABLE:
1264 				if (ci_otg_is_fsm_mode(ci)) {
1265 					ci->gadget.b_hnp_enable = 1;
1266 					err = isr_setup_status_phase(
1267 							ci);
1268 				}
1269 				break;
1270 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1271 				if (ci_otg_is_fsm_mode(ci))
1272 					err = otg_a_alt_hnp_support(ci);
1273 				break;
1274 			case USB_DEVICE_A_HNP_SUPPORT:
1275 				if (ci_otg_is_fsm_mode(ci)) {
1276 					ci->gadget.a_hnp_support = 1;
1277 					err = isr_setup_status_phase(
1278 							ci);
1279 				}
1280 				break;
1281 			default:
1282 				goto delegate;
1283 			}
1284 		} else {
1285 			goto delegate;
1286 		}
1287 		break;
1288 	default:
1289 delegate:
1290 		if (req.wLength == 0)   /* no data phase */
1291 			ci->ep0_dir = TX;
1292 
1293 		spin_unlock(&ci->lock);
1294 		err = ci->driver->setup(&ci->gadget, &req);
1295 		spin_lock(&ci->lock);
1296 		break;
1297 	}
1298 
1299 	if (err < 0) {
1300 		spin_unlock(&ci->lock);
1301 		if (_ep_set_halt(&hwep->ep, 1, false))
1302 			dev_err(ci->dev, "error: _ep_set_halt\n");
1303 		spin_lock(&ci->lock);
1304 	}
1305 }
1306 
1307 /**
1308  * isr_tr_complete_handler: transaction complete interrupt handler
1309  * @ci: UDC descriptor
1310  *
1311  * This function handles traffic events
1312  */
1313 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1314 __releases(ci->lock)
1315 __acquires(ci->lock)
1316 {
1317 	unsigned i;
1318 	int err;
1319 
1320 	for (i = 0; i < ci->hw_ep_max; i++) {
1321 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1322 
1323 		if (hwep->ep.desc == NULL)
1324 			continue;   /* not configured */
1325 
1326 		if (hw_test_and_clear_complete(ci, i)) {
1327 			err = isr_tr_complete_low(hwep);
1328 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1329 				if (err > 0)   /* needs status phase */
1330 					err = isr_setup_status_phase(ci);
1331 				if (err < 0) {
1332 					spin_unlock(&ci->lock);
1333 					if (_ep_set_halt(&hwep->ep, 1, false))
1334 						dev_err(ci->dev,
1335 						"error: _ep_set_halt\n");
1336 					spin_lock(&ci->lock);
1337 				}
1338 			}
1339 		}
1340 
1341 		/* Only handle setup packet below */
1342 		if (i == 0 &&
1343 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1344 			isr_setup_packet_handler(ci);
1345 	}
1346 }
1347 
1348 /******************************************************************************
1349  * ENDPT block
1350  *****************************************************************************/
1351 /*
1352  * ep_enable: configure endpoint, making it usable
1353  *
1354  * Check usb_ep_enable() at "usb_gadget.h" for details
1355  */
1356 static int ep_enable(struct usb_ep *ep,
1357 		     const struct usb_endpoint_descriptor *desc)
1358 {
1359 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1360 	int retval = 0;
1361 	unsigned long flags;
1362 	u32 cap = 0;
1363 
1364 	if (ep == NULL || desc == NULL)
1365 		return -EINVAL;
1366 
1367 	spin_lock_irqsave(hwep->lock, flags);
1368 
1369 	/* only internal SW should enable ctrl endpts */
1370 
1371 	if (!list_empty(&hwep->qh.queue)) {
1372 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1373 		spin_unlock_irqrestore(hwep->lock, flags);
1374 		return -EBUSY;
1375 	}
1376 
1377 	hwep->ep.desc = desc;
1378 
1379 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1380 	hwep->num  = usb_endpoint_num(desc);
1381 	hwep->type = usb_endpoint_type(desc);
1382 
1383 	hwep->ep.maxpacket = usb_endpoint_maxp(desc);
1384 	hwep->ep.mult = usb_endpoint_maxp_mult(desc);
1385 
1386 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1387 		cap |= QH_IOS;
1388 
1389 	cap |= QH_ZLT;
1390 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1391 	/*
1392 	 * For ISO-TX, we set mult at QH as the largest value, and use
1393 	 * MultO at TD as real mult value.
1394 	 */
1395 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1396 		cap |= 3 << __ffs(QH_MULT);
1397 
1398 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1399 
1400 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1401 
1402 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1403 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1404 		retval = -EINVAL;
1405 	}
1406 
1407 	/*
1408 	 * Enable endpoints in the HW other than ep0 as ep0
1409 	 * is always enabled
1410 	 */
1411 	if (hwep->num)
1412 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1413 				       hwep->type);
1414 
1415 	spin_unlock_irqrestore(hwep->lock, flags);
1416 	return retval;
1417 }
1418 
1419 /*
1420  * ep_disable: endpoint is no longer usable
1421  *
1422  * Check usb_ep_disable() at "usb_gadget.h" for details
1423  */
1424 static int ep_disable(struct usb_ep *ep)
1425 {
1426 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1427 	int direction, retval = 0;
1428 	unsigned long flags;
1429 
1430 	if (ep == NULL)
1431 		return -EINVAL;
1432 	else if (hwep->ep.desc == NULL)
1433 		return -EBUSY;
1434 
1435 	spin_lock_irqsave(hwep->lock, flags);
1436 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1437 		spin_unlock_irqrestore(hwep->lock, flags);
1438 		return 0;
1439 	}
1440 
1441 	/* only internal SW should disable ctrl endpts */
1442 
1443 	direction = hwep->dir;
1444 	do {
1445 		retval |= _ep_nuke(hwep);
1446 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1447 
1448 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1449 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1450 
1451 	} while (hwep->dir != direction);
1452 
1453 	hwep->ep.desc = NULL;
1454 
1455 	spin_unlock_irqrestore(hwep->lock, flags);
1456 	return retval;
1457 }
1458 
1459 /*
1460  * ep_alloc_request: allocate a request object to use with this endpoint
1461  *
1462  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1463  */
1464 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1465 {
1466 	struct ci_hw_req *hwreq = NULL;
1467 
1468 	if (ep == NULL)
1469 		return NULL;
1470 
1471 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1472 	if (hwreq != NULL) {
1473 		INIT_LIST_HEAD(&hwreq->queue);
1474 		INIT_LIST_HEAD(&hwreq->tds);
1475 	}
1476 
1477 	return (hwreq == NULL) ? NULL : &hwreq->req;
1478 }
1479 
1480 /*
1481  * ep_free_request: frees a request object
1482  *
1483  * Check usb_ep_free_request() at "usb_gadget.h" for details
1484  */
1485 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1486 {
1487 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1488 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1489 	struct td_node *node, *tmpnode;
1490 	unsigned long flags;
1491 
1492 	if (ep == NULL || req == NULL) {
1493 		return;
1494 	} else if (!list_empty(&hwreq->queue)) {
1495 		dev_err(hwep->ci->dev, "freeing queued request\n");
1496 		return;
1497 	}
1498 
1499 	spin_lock_irqsave(hwep->lock, flags);
1500 
1501 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1502 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1503 		list_del_init(&node->td);
1504 		node->ptr = NULL;
1505 		kfree(node);
1506 	}
1507 
1508 	kfree(hwreq);
1509 
1510 	spin_unlock_irqrestore(hwep->lock, flags);
1511 }
1512 
1513 /*
1514  * ep_queue: queues (submits) an I/O request to an endpoint
1515  *
1516  * Check usb_ep_queue()* at usb_gadget.h" for details
1517  */
1518 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1519 		    gfp_t __maybe_unused gfp_flags)
1520 {
1521 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1522 	int retval = 0;
1523 	unsigned long flags;
1524 
1525 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1526 		return -EINVAL;
1527 
1528 	spin_lock_irqsave(hwep->lock, flags);
1529 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1530 		spin_unlock_irqrestore(hwep->lock, flags);
1531 		return 0;
1532 	}
1533 	retval = _ep_queue(ep, req, gfp_flags);
1534 	spin_unlock_irqrestore(hwep->lock, flags);
1535 	return retval;
1536 }
1537 
1538 /*
1539  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1540  *
1541  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1542  */
1543 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1544 {
1545 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1546 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1547 	unsigned long flags;
1548 	struct td_node *node, *tmpnode;
1549 
1550 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1551 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1552 		list_empty(&hwep->qh.queue))
1553 		return -EINVAL;
1554 
1555 	spin_lock_irqsave(hwep->lock, flags);
1556 	if (hwep->ci->gadget.speed != USB_SPEED_UNKNOWN)
1557 		hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1558 
1559 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1560 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1561 		list_del(&node->td);
1562 		kfree(node);
1563 	}
1564 
1565 	/* pop request */
1566 	list_del_init(&hwreq->queue);
1567 
1568 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1569 
1570 	req->status = -ECONNRESET;
1571 
1572 	if (hwreq->req.complete != NULL) {
1573 		spin_unlock(hwep->lock);
1574 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1575 		spin_lock(hwep->lock);
1576 	}
1577 
1578 	spin_unlock_irqrestore(hwep->lock, flags);
1579 	return 0;
1580 }
1581 
1582 /*
1583  * ep_set_halt: sets the endpoint halt feature
1584  *
1585  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1586  */
1587 static int ep_set_halt(struct usb_ep *ep, int value)
1588 {
1589 	return _ep_set_halt(ep, value, true);
1590 }
1591 
1592 /*
1593  * ep_set_wedge: sets the halt feature and ignores clear requests
1594  *
1595  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1596  */
1597 static int ep_set_wedge(struct usb_ep *ep)
1598 {
1599 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1600 	unsigned long flags;
1601 
1602 	if (ep == NULL || hwep->ep.desc == NULL)
1603 		return -EINVAL;
1604 
1605 	spin_lock_irqsave(hwep->lock, flags);
1606 	hwep->wedge = 1;
1607 	spin_unlock_irqrestore(hwep->lock, flags);
1608 
1609 	return usb_ep_set_halt(ep);
1610 }
1611 
1612 /*
1613  * ep_fifo_flush: flushes contents of a fifo
1614  *
1615  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1616  */
1617 static void ep_fifo_flush(struct usb_ep *ep)
1618 {
1619 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1620 	unsigned long flags;
1621 
1622 	if (ep == NULL) {
1623 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1624 		return;
1625 	}
1626 
1627 	spin_lock_irqsave(hwep->lock, flags);
1628 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1629 		spin_unlock_irqrestore(hwep->lock, flags);
1630 		return;
1631 	}
1632 
1633 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1634 
1635 	spin_unlock_irqrestore(hwep->lock, flags);
1636 }
1637 
1638 /*
1639  * Endpoint-specific part of the API to the USB controller hardware
1640  * Check "usb_gadget.h" for details
1641  */
1642 static const struct usb_ep_ops usb_ep_ops = {
1643 	.enable	       = ep_enable,
1644 	.disable       = ep_disable,
1645 	.alloc_request = ep_alloc_request,
1646 	.free_request  = ep_free_request,
1647 	.queue	       = ep_queue,
1648 	.dequeue       = ep_dequeue,
1649 	.set_halt      = ep_set_halt,
1650 	.set_wedge     = ep_set_wedge,
1651 	.fifo_flush    = ep_fifo_flush,
1652 };
1653 
1654 /******************************************************************************
1655  * GADGET block
1656  *****************************************************************************/
1657 
1658 static int ci_udc_get_frame(struct usb_gadget *_gadget)
1659 {
1660 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1661 	unsigned long flags;
1662 	int ret;
1663 
1664 	spin_lock_irqsave(&ci->lock, flags);
1665 	ret = hw_read(ci, OP_FRINDEX, 0x3fff);
1666 	spin_unlock_irqrestore(&ci->lock, flags);
1667 	return ret >> 3;
1668 }
1669 
1670 /*
1671  * ci_hdrc_gadget_connect: caller makes sure gadget driver is binded
1672  */
1673 static void ci_hdrc_gadget_connect(struct usb_gadget *_gadget, int is_active)
1674 {
1675 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1676 
1677 	if (is_active) {
1678 		pm_runtime_get_sync(ci->dev);
1679 		hw_device_reset(ci);
1680 		spin_lock_irq(&ci->lock);
1681 		if (ci->driver) {
1682 			hw_device_state(ci, ci->ep0out->qh.dma);
1683 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1684 			spin_unlock_irq(&ci->lock);
1685 			usb_udc_vbus_handler(_gadget, true);
1686 		} else {
1687 			spin_unlock_irq(&ci->lock);
1688 		}
1689 	} else {
1690 		usb_udc_vbus_handler(_gadget, false);
1691 		if (ci->driver)
1692 			ci->driver->disconnect(&ci->gadget);
1693 		hw_device_state(ci, 0);
1694 		if (ci->platdata->notify_event)
1695 			ci->platdata->notify_event(ci,
1696 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1697 		_gadget_stop_activity(&ci->gadget);
1698 		pm_runtime_put_sync(ci->dev);
1699 		usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1700 	}
1701 }
1702 
1703 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1704 {
1705 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1706 	unsigned long flags;
1707 	int ret = 0;
1708 
1709 	spin_lock_irqsave(&ci->lock, flags);
1710 	ci->vbus_active = is_active;
1711 	spin_unlock_irqrestore(&ci->lock, flags);
1712 
1713 	if (ci->usb_phy)
1714 		usb_phy_set_charger_state(ci->usb_phy, is_active ?
1715 			USB_CHARGER_PRESENT : USB_CHARGER_ABSENT);
1716 
1717 	if (ci->platdata->notify_event)
1718 		ret = ci->platdata->notify_event(ci,
1719 				CI_HDRC_CONTROLLER_VBUS_EVENT);
1720 
1721 	if (ci->driver)
1722 		ci_hdrc_gadget_connect(_gadget, is_active);
1723 
1724 	return ret;
1725 }
1726 
1727 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1728 {
1729 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1730 	unsigned long flags;
1731 	int ret = 0;
1732 
1733 	spin_lock_irqsave(&ci->lock, flags);
1734 	if (ci->gadget.speed == USB_SPEED_UNKNOWN) {
1735 		spin_unlock_irqrestore(&ci->lock, flags);
1736 		return 0;
1737 	}
1738 	if (!ci->remote_wakeup) {
1739 		ret = -EOPNOTSUPP;
1740 		goto out;
1741 	}
1742 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1743 		ret = -EINVAL;
1744 		goto out;
1745 	}
1746 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1747 out:
1748 	spin_unlock_irqrestore(&ci->lock, flags);
1749 	return ret;
1750 }
1751 
1752 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1753 {
1754 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1755 
1756 	if (ci->usb_phy)
1757 		return usb_phy_set_power(ci->usb_phy, ma);
1758 	return -ENOTSUPP;
1759 }
1760 
1761 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1762 {
1763 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1764 	struct ci_hw_ep *hwep = ci->ep0in;
1765 	unsigned long flags;
1766 
1767 	spin_lock_irqsave(hwep->lock, flags);
1768 	_gadget->is_selfpowered = (is_on != 0);
1769 	spin_unlock_irqrestore(hwep->lock, flags);
1770 
1771 	return 0;
1772 }
1773 
1774 /* Change Data+ pullup status
1775  * this func is used by usb_gadget_connect/disconnect
1776  */
1777 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1778 {
1779 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1780 
1781 	/*
1782 	 * Data+ pullup controlled by OTG state machine in OTG fsm mode;
1783 	 * and don't touch Data+ in host mode for dual role config.
1784 	 */
1785 	if (ci_otg_is_fsm_mode(ci) || ci->role == CI_ROLE_HOST)
1786 		return 0;
1787 
1788 	pm_runtime_get_sync(ci->dev);
1789 	if (is_on)
1790 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1791 	else
1792 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1793 	pm_runtime_put_sync(ci->dev);
1794 
1795 	return 0;
1796 }
1797 
1798 static int ci_udc_start(struct usb_gadget *gadget,
1799 			 struct usb_gadget_driver *driver);
1800 static int ci_udc_stop(struct usb_gadget *gadget);
1801 
1802 /* Match ISOC IN from the highest endpoint */
1803 static struct usb_ep *ci_udc_match_ep(struct usb_gadget *gadget,
1804 			      struct usb_endpoint_descriptor *desc,
1805 			      struct usb_ss_ep_comp_descriptor *comp_desc)
1806 {
1807 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1808 	struct usb_ep *ep;
1809 
1810 	if (usb_endpoint_xfer_isoc(desc) && usb_endpoint_dir_in(desc)) {
1811 		list_for_each_entry_reverse(ep, &ci->gadget.ep_list, ep_list) {
1812 			if (ep->caps.dir_in && !ep->claimed)
1813 				return ep;
1814 		}
1815 	}
1816 
1817 	return NULL;
1818 }
1819 
1820 /*
1821  * Device operations part of the API to the USB controller hardware,
1822  * which don't involve endpoints (or i/o)
1823  * Check  "usb_gadget.h" for details
1824  */
1825 static const struct usb_gadget_ops usb_gadget_ops = {
1826 	.get_frame	= ci_udc_get_frame,
1827 	.vbus_session	= ci_udc_vbus_session,
1828 	.wakeup		= ci_udc_wakeup,
1829 	.set_selfpowered	= ci_udc_selfpowered,
1830 	.pullup		= ci_udc_pullup,
1831 	.vbus_draw	= ci_udc_vbus_draw,
1832 	.udc_start	= ci_udc_start,
1833 	.udc_stop	= ci_udc_stop,
1834 	.match_ep 	= ci_udc_match_ep,
1835 };
1836 
1837 static int init_eps(struct ci_hdrc *ci)
1838 {
1839 	int retval = 0, i, j;
1840 
1841 	for (i = 0; i < ci->hw_ep_max/2; i++)
1842 		for (j = RX; j <= TX; j++) {
1843 			int k = i + j * ci->hw_ep_max/2;
1844 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1845 
1846 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1847 					(j == TX)  ? "in" : "out");
1848 
1849 			hwep->ci          = ci;
1850 			hwep->lock         = &ci->lock;
1851 			hwep->td_pool      = ci->td_pool;
1852 
1853 			hwep->ep.name      = hwep->name;
1854 			hwep->ep.ops       = &usb_ep_ops;
1855 
1856 			if (i == 0) {
1857 				hwep->ep.caps.type_control = true;
1858 			} else {
1859 				hwep->ep.caps.type_iso = true;
1860 				hwep->ep.caps.type_bulk = true;
1861 				hwep->ep.caps.type_int = true;
1862 			}
1863 
1864 			if (j == TX)
1865 				hwep->ep.caps.dir_in = true;
1866 			else
1867 				hwep->ep.caps.dir_out = true;
1868 
1869 			/*
1870 			 * for ep0: maxP defined in desc, for other
1871 			 * eps, maxP is set by epautoconfig() called
1872 			 * by gadget layer
1873 			 */
1874 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1875 
1876 			INIT_LIST_HEAD(&hwep->qh.queue);
1877 			hwep->qh.ptr = dma_pool_zalloc(ci->qh_pool, GFP_KERNEL,
1878 						       &hwep->qh.dma);
1879 			if (hwep->qh.ptr == NULL)
1880 				retval = -ENOMEM;
1881 
1882 			/*
1883 			 * set up shorthands for ep0 out and in endpoints,
1884 			 * don't add to gadget's ep_list
1885 			 */
1886 			if (i == 0) {
1887 				if (j == RX)
1888 					ci->ep0out = hwep;
1889 				else
1890 					ci->ep0in = hwep;
1891 
1892 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1893 				continue;
1894 			}
1895 
1896 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1897 		}
1898 
1899 	return retval;
1900 }
1901 
1902 static void destroy_eps(struct ci_hdrc *ci)
1903 {
1904 	int i;
1905 
1906 	for (i = 0; i < ci->hw_ep_max; i++) {
1907 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1908 
1909 		if (hwep->pending_td)
1910 			free_pending_td(hwep);
1911 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1912 	}
1913 }
1914 
1915 /**
1916  * ci_udc_start: register a gadget driver
1917  * @gadget: our gadget
1918  * @driver: the driver being registered
1919  *
1920  * Interrupts are enabled here.
1921  */
1922 static int ci_udc_start(struct usb_gadget *gadget,
1923 			 struct usb_gadget_driver *driver)
1924 {
1925 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1926 	int retval;
1927 
1928 	if (driver->disconnect == NULL)
1929 		return -EINVAL;
1930 
1931 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1932 	retval = usb_ep_enable(&ci->ep0out->ep);
1933 	if (retval)
1934 		return retval;
1935 
1936 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1937 	retval = usb_ep_enable(&ci->ep0in->ep);
1938 	if (retval)
1939 		return retval;
1940 
1941 	ci->driver = driver;
1942 
1943 	/* Start otg fsm for B-device */
1944 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1945 		ci_hdrc_otg_fsm_start(ci);
1946 		return retval;
1947 	}
1948 
1949 	if (ci->vbus_active)
1950 		ci_hdrc_gadget_connect(gadget, 1);
1951 	else
1952 		usb_udc_vbus_handler(&ci->gadget, false);
1953 
1954 	return retval;
1955 }
1956 
1957 static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
1958 {
1959 	if (!ci_otg_is_fsm_mode(ci))
1960 		return;
1961 
1962 	mutex_lock(&ci->fsm.lock);
1963 	if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
1964 		ci->fsm.a_bidl_adis_tmout = 1;
1965 		ci_hdrc_otg_fsm_start(ci);
1966 	} else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
1967 		ci->fsm.protocol = PROTO_UNDEF;
1968 		ci->fsm.otg->state = OTG_STATE_UNDEFINED;
1969 	}
1970 	mutex_unlock(&ci->fsm.lock);
1971 }
1972 
1973 /*
1974  * ci_udc_stop: unregister a gadget driver
1975  */
1976 static int ci_udc_stop(struct usb_gadget *gadget)
1977 {
1978 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1979 	unsigned long flags;
1980 
1981 	spin_lock_irqsave(&ci->lock, flags);
1982 	ci->driver = NULL;
1983 
1984 	if (ci->vbus_active) {
1985 		hw_device_state(ci, 0);
1986 		spin_unlock_irqrestore(&ci->lock, flags);
1987 		if (ci->platdata->notify_event)
1988 			ci->platdata->notify_event(ci,
1989 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1990 		_gadget_stop_activity(&ci->gadget);
1991 		spin_lock_irqsave(&ci->lock, flags);
1992 		pm_runtime_put(ci->dev);
1993 	}
1994 
1995 	spin_unlock_irqrestore(&ci->lock, flags);
1996 
1997 	ci_udc_stop_for_otg_fsm(ci);
1998 	return 0;
1999 }
2000 
2001 /******************************************************************************
2002  * BUS block
2003  *****************************************************************************/
2004 /*
2005  * udc_irq: ci interrupt handler
2006  *
2007  * This function returns IRQ_HANDLED if the IRQ has been handled
2008  * It locks access to registers
2009  */
2010 static irqreturn_t udc_irq(struct ci_hdrc *ci)
2011 {
2012 	irqreturn_t retval;
2013 	u32 intr;
2014 
2015 	if (ci == NULL)
2016 		return IRQ_HANDLED;
2017 
2018 	spin_lock(&ci->lock);
2019 
2020 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
2021 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
2022 				USBMODE_CM_DC) {
2023 			spin_unlock(&ci->lock);
2024 			return IRQ_NONE;
2025 		}
2026 	}
2027 	intr = hw_test_and_clear_intr_active(ci);
2028 
2029 	if (intr) {
2030 		/* order defines priority - do NOT change it */
2031 		if (USBi_URI & intr)
2032 			isr_reset_handler(ci);
2033 
2034 		if (USBi_PCI & intr) {
2035 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
2036 				USB_SPEED_HIGH : USB_SPEED_FULL;
2037 			if (ci->suspended) {
2038 				if (ci->driver->resume) {
2039 					spin_unlock(&ci->lock);
2040 					ci->driver->resume(&ci->gadget);
2041 					spin_lock(&ci->lock);
2042 				}
2043 				ci->suspended = 0;
2044 				usb_gadget_set_state(&ci->gadget,
2045 						ci->resume_state);
2046 			}
2047 		}
2048 
2049 		if (USBi_UI  & intr)
2050 			isr_tr_complete_handler(ci);
2051 
2052 		if ((USBi_SLI & intr) && !(ci->suspended)) {
2053 			ci->suspended = 1;
2054 			ci->resume_state = ci->gadget.state;
2055 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
2056 			    ci->driver->suspend) {
2057 				spin_unlock(&ci->lock);
2058 				ci->driver->suspend(&ci->gadget);
2059 				spin_lock(&ci->lock);
2060 			}
2061 			usb_gadget_set_state(&ci->gadget,
2062 					USB_STATE_SUSPENDED);
2063 		}
2064 		retval = IRQ_HANDLED;
2065 	} else {
2066 		retval = IRQ_NONE;
2067 	}
2068 	spin_unlock(&ci->lock);
2069 
2070 	return retval;
2071 }
2072 
2073 /**
2074  * udc_start: initialize gadget role
2075  * @ci: chipidea controller
2076  */
2077 static int udc_start(struct ci_hdrc *ci)
2078 {
2079 	struct device *dev = ci->dev;
2080 	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
2081 	int retval = 0;
2082 
2083 	ci->gadget.ops          = &usb_gadget_ops;
2084 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
2085 	ci->gadget.max_speed    = USB_SPEED_HIGH;
2086 	ci->gadget.name         = ci->platdata->name;
2087 	ci->gadget.otg_caps	= otg_caps;
2088 	ci->gadget.sg_supported = 1;
2089 	ci->gadget.irq		= ci->irq;
2090 
2091 	if (ci->platdata->flags & CI_HDRC_REQUIRES_ALIGNED_DMA)
2092 		ci->gadget.quirk_avoids_skb_reserve = 1;
2093 
2094 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
2095 						otg_caps->adp_support))
2096 		ci->gadget.is_otg = 1;
2097 
2098 	INIT_LIST_HEAD(&ci->gadget.ep_list);
2099 
2100 	/* alloc resources */
2101 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev->parent,
2102 				       sizeof(struct ci_hw_qh),
2103 				       64, CI_HDRC_PAGE_SIZE);
2104 	if (ci->qh_pool == NULL)
2105 		return -ENOMEM;
2106 
2107 	ci->td_pool = dma_pool_create("ci_hw_td", dev->parent,
2108 				       sizeof(struct ci_hw_td),
2109 				       64, CI_HDRC_PAGE_SIZE);
2110 	if (ci->td_pool == NULL) {
2111 		retval = -ENOMEM;
2112 		goto free_qh_pool;
2113 	}
2114 
2115 	retval = init_eps(ci);
2116 	if (retval)
2117 		goto free_pools;
2118 
2119 	ci->gadget.ep0 = &ci->ep0in->ep;
2120 
2121 	retval = usb_add_gadget_udc(dev, &ci->gadget);
2122 	if (retval)
2123 		goto destroy_eps;
2124 
2125 	return retval;
2126 
2127 destroy_eps:
2128 	destroy_eps(ci);
2129 free_pools:
2130 	dma_pool_destroy(ci->td_pool);
2131 free_qh_pool:
2132 	dma_pool_destroy(ci->qh_pool);
2133 	return retval;
2134 }
2135 
2136 /*
2137  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
2138  *
2139  * No interrupts active, the IRQ has been released
2140  */
2141 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
2142 {
2143 	if (!ci->roles[CI_ROLE_GADGET])
2144 		return;
2145 
2146 	usb_del_gadget_udc(&ci->gadget);
2147 
2148 	destroy_eps(ci);
2149 
2150 	dma_pool_destroy(ci->td_pool);
2151 	dma_pool_destroy(ci->qh_pool);
2152 }
2153 
2154 static int udc_id_switch_for_device(struct ci_hdrc *ci)
2155 {
2156 	if (ci->platdata->pins_device)
2157 		pinctrl_select_state(ci->platdata->pctl,
2158 				     ci->platdata->pins_device);
2159 
2160 	if (ci->is_otg)
2161 		/* Clear and enable BSV irq */
2162 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
2163 					OTGSC_BSVIS | OTGSC_BSVIE);
2164 
2165 	return 0;
2166 }
2167 
2168 static void udc_id_switch_for_host(struct ci_hdrc *ci)
2169 {
2170 	/*
2171 	 * host doesn't care B_SESSION_VALID event
2172 	 * so clear and disable BSV irq
2173 	 */
2174 	if (ci->is_otg)
2175 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
2176 
2177 	ci->vbus_active = 0;
2178 
2179 	if (ci->platdata->pins_device && ci->platdata->pins_default)
2180 		pinctrl_select_state(ci->platdata->pctl,
2181 				     ci->platdata->pins_default);
2182 }
2183 
2184 /**
2185  * ci_hdrc_gadget_init - initialize device related bits
2186  * @ci: the controller
2187  *
2188  * This function initializes the gadget, if the device is "device capable".
2189  */
2190 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
2191 {
2192 	struct ci_role_driver *rdrv;
2193 	int ret;
2194 
2195 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
2196 		return -ENXIO;
2197 
2198 	rdrv = devm_kzalloc(ci->dev, sizeof(*rdrv), GFP_KERNEL);
2199 	if (!rdrv)
2200 		return -ENOMEM;
2201 
2202 	rdrv->start	= udc_id_switch_for_device;
2203 	rdrv->stop	= udc_id_switch_for_host;
2204 	rdrv->irq	= udc_irq;
2205 	rdrv->name	= "gadget";
2206 
2207 	ret = udc_start(ci);
2208 	if (!ret)
2209 		ci->roles[CI_ROLE_GADGET] = rdrv;
2210 
2211 	return ret;
2212 }
2213