xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision 38145ed12ed9935377fec40e0c3f50fbdda1e148)
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 
30 /* control endpoint description */
31 static const struct usb_endpoint_descriptor
32 ctrl_endpt_out_desc = {
33 	.bLength         = USB_DT_ENDPOINT_SIZE,
34 	.bDescriptorType = USB_DT_ENDPOINT,
35 
36 	.bEndpointAddress = USB_DIR_OUT,
37 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
38 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
39 };
40 
41 static const struct usb_endpoint_descriptor
42 ctrl_endpt_in_desc = {
43 	.bLength         = USB_DT_ENDPOINT_SIZE,
44 	.bDescriptorType = USB_DT_ENDPOINT,
45 
46 	.bEndpointAddress = USB_DIR_IN,
47 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
48 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
49 };
50 
51 /**
52  * hw_ep_bit: calculates the bit number
53  * @num: endpoint number
54  * @dir: endpoint direction
55  *
56  * This function returns bit number
57  */
58 static inline int hw_ep_bit(int num, int dir)
59 {
60 	return num + ((dir == TX) ? 16 : 0);
61 }
62 
63 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
64 {
65 	int fill = 16 - ci->hw_ep_max / 2;
66 
67 	if (n >= ci->hw_ep_max / 2)
68 		n += fill;
69 
70 	return n;
71 }
72 
73 /**
74  * hw_device_state: enables/disables interrupts (execute without interruption)
75  * @dma: 0 => disable, !0 => enable and set dma engine
76  *
77  * This function returns an error code
78  */
79 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
80 {
81 	if (dma) {
82 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
83 		/* interrupt, error, port change, reset, sleep/suspend */
84 		hw_write(ci, OP_USBINTR, ~0,
85 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
86 	} else {
87 		hw_write(ci, OP_USBINTR, ~0, 0);
88 	}
89 	return 0;
90 }
91 
92 /**
93  * hw_ep_flush: flush endpoint fifo (execute without interruption)
94  * @num: endpoint number
95  * @dir: endpoint direction
96  *
97  * This function returns an error code
98  */
99 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
100 {
101 	int n = hw_ep_bit(num, dir);
102 
103 	do {
104 		/* flush any pending transfer */
105 		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
106 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
107 			cpu_relax();
108 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
109 
110 	return 0;
111 }
112 
113 /**
114  * hw_ep_disable: disables endpoint (execute without interruption)
115  * @num: endpoint number
116  * @dir: endpoint direction
117  *
118  * This function returns an error code
119  */
120 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
121 {
122 	hw_write(ci, OP_ENDPTCTRL + num,
123 		 (dir == TX) ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
124 	return 0;
125 }
126 
127 /**
128  * hw_ep_enable: enables endpoint (execute without interruption)
129  * @num:  endpoint number
130  * @dir:  endpoint direction
131  * @type: endpoint type
132  *
133  * This function returns an error code
134  */
135 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
136 {
137 	u32 mask, data;
138 
139 	if (dir == TX) {
140 		mask  = ENDPTCTRL_TXT;  /* type    */
141 		data  = type << __ffs(mask);
142 
143 		mask |= ENDPTCTRL_TXS;  /* unstall */
144 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
145 		data |= ENDPTCTRL_TXR;
146 		mask |= ENDPTCTRL_TXE;  /* enable  */
147 		data |= ENDPTCTRL_TXE;
148 	} else {
149 		mask  = ENDPTCTRL_RXT;  /* type    */
150 		data  = type << __ffs(mask);
151 
152 		mask |= ENDPTCTRL_RXS;  /* unstall */
153 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
154 		data |= ENDPTCTRL_RXR;
155 		mask |= ENDPTCTRL_RXE;  /* enable  */
156 		data |= ENDPTCTRL_RXE;
157 	}
158 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
159 	return 0;
160 }
161 
162 /**
163  * hw_ep_get_halt: return endpoint halt status
164  * @num: endpoint number
165  * @dir: endpoint direction
166  *
167  * This function returns 1 if endpoint halted
168  */
169 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
170 {
171 	u32 mask = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
172 
173 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
174 }
175 
176 /**
177  * hw_ep_prime: primes endpoint (execute without interruption)
178  * @num:     endpoint number
179  * @dir:     endpoint direction
180  * @is_ctrl: true if control endpoint
181  *
182  * This function returns an error code
183  */
184 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
185 {
186 	int n = hw_ep_bit(num, dir);
187 
188 	/* Synchronize before ep prime */
189 	wmb();
190 
191 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
192 		return -EAGAIN;
193 
194 	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
195 
196 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
197 		cpu_relax();
198 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
199 		return -EAGAIN;
200 
201 	/* status shoult be tested according with manual but it doesn't work */
202 	return 0;
203 }
204 
205 /**
206  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
207  *                 without interruption)
208  * @num:   endpoint number
209  * @dir:   endpoint direction
210  * @value: true => stall, false => unstall
211  *
212  * This function returns an error code
213  */
214 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
215 {
216 	if (value != 0 && value != 1)
217 		return -EINVAL;
218 
219 	do {
220 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
221 		u32 mask_xs = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
222 		u32 mask_xr = (dir == TX) ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
223 
224 		/* data toggle - reserved for EP0 but it's in ESS */
225 		hw_write(ci, reg, mask_xs|mask_xr,
226 			  value ? mask_xs : mask_xr);
227 	} while (value != hw_ep_get_halt(ci, num, dir));
228 
229 	return 0;
230 }
231 
232 /**
233  * hw_is_port_high_speed: test if port is high speed
234  *
235  * This function returns true if high speed port
236  */
237 static int hw_port_is_high_speed(struct ci_hdrc *ci)
238 {
239 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
240 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
241 }
242 
243 /**
244  * hw_test_and_clear_complete: test & clear complete status (execute without
245  *                             interruption)
246  * @n: endpoint number
247  *
248  * This function returns complete status
249  */
250 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
251 {
252 	n = ep_to_bit(ci, n);
253 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
254 }
255 
256 /**
257  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
258  *                                without interruption)
259  *
260  * This function returns active interrutps
261  */
262 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
263 {
264 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
265 
266 	hw_write(ci, OP_USBSTS, ~0, reg);
267 	return reg;
268 }
269 
270 /**
271  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
272  *                                interruption)
273  *
274  * This function returns guard value
275  */
276 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
277 {
278 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
279 }
280 
281 /**
282  * hw_test_and_set_setup_guard: test & set setup guard (execute without
283  *                              interruption)
284  *
285  * This function returns guard value
286  */
287 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
288 {
289 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
290 }
291 
292 /**
293  * hw_usb_set_address: configures USB address (execute without interruption)
294  * @value: new USB address
295  *
296  * This function explicitly sets the address, without the "USBADRA" (advance)
297  * feature, which is not supported by older versions of the controller.
298  */
299 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
300 {
301 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
302 		 value << __ffs(DEVICEADDR_USBADR));
303 }
304 
305 /**
306  * hw_usb_reset: restart device after a bus reset (execute without
307  *               interruption)
308  *
309  * This function returns an error code
310  */
311 static int hw_usb_reset(struct ci_hdrc *ci)
312 {
313 	hw_usb_set_address(ci, 0);
314 
315 	/* ESS flushes only at end?!? */
316 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
317 
318 	/* clear setup token semaphores */
319 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
320 
321 	/* clear complete status */
322 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
323 
324 	/* wait until all bits cleared */
325 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
326 		udelay(10);             /* not RTOS friendly */
327 
328 	/* reset all endpoints ? */
329 
330 	/* reset internal status and wait for further instructions
331 	   no need to verify the port reset status (ESS does it) */
332 
333 	return 0;
334 }
335 
336 /******************************************************************************
337  * UTIL block
338  *****************************************************************************/
339 
340 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
341 			unsigned int length, struct scatterlist *s)
342 {
343 	int i;
344 	u32 temp;
345 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
346 						  GFP_ATOMIC);
347 
348 	if (node == NULL)
349 		return -ENOMEM;
350 
351 	node->ptr = dma_pool_zalloc(hwep->td_pool, GFP_ATOMIC, &node->dma);
352 	if (node->ptr == NULL) {
353 		kfree(node);
354 		return -ENOMEM;
355 	}
356 
357 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
358 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
359 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
360 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
361 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
362 
363 		if (hwreq->req.length == 0
364 				|| hwreq->req.length % hwep->ep.maxpacket)
365 			mul++;
366 		node->ptr->token |= cpu_to_le32(mul << __ffs(TD_MULTO));
367 	}
368 
369 	if (s) {
370 		temp = (u32) (sg_dma_address(s) + hwreq->req.actual);
371 		node->td_remaining_size = CI_MAX_BUF_SIZE - length;
372 	} else {
373 		temp = (u32) (hwreq->req.dma + hwreq->req.actual);
374 	}
375 
376 	if (length) {
377 		node->ptr->page[0] = cpu_to_le32(temp);
378 		for (i = 1; i < TD_PAGE_COUNT; i++) {
379 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
380 			page &= ~TD_RESERVED_MASK;
381 			node->ptr->page[i] = cpu_to_le32(page);
382 		}
383 	}
384 
385 	hwreq->req.actual += length;
386 
387 	if (!list_empty(&hwreq->tds)) {
388 		/* get the last entry */
389 		lastnode = list_entry(hwreq->tds.prev,
390 				struct td_node, td);
391 		lastnode->ptr->next = cpu_to_le32(node->dma);
392 	}
393 
394 	INIT_LIST_HEAD(&node->td);
395 	list_add_tail(&node->td, &hwreq->tds);
396 
397 	return 0;
398 }
399 
400 /**
401  * _usb_addr: calculates endpoint address from direction & number
402  * @ep:  endpoint
403  */
404 static inline u8 _usb_addr(struct ci_hw_ep *ep)
405 {
406 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
407 }
408 
409 static int prepare_td_for_non_sg(struct ci_hw_ep *hwep,
410 		struct ci_hw_req *hwreq)
411 {
412 	unsigned int rest = hwreq->req.length;
413 	int pages = TD_PAGE_COUNT;
414 	int ret = 0;
415 
416 	if (rest == 0) {
417 		ret = add_td_to_list(hwep, hwreq, 0, NULL);
418 		if (ret < 0)
419 			return ret;
420 	}
421 
422 	/*
423 	 * The first buffer could be not page aligned.
424 	 * In that case we have to span into one extra td.
425 	 */
426 	if (hwreq->req.dma % PAGE_SIZE)
427 		pages--;
428 
429 	while (rest > 0) {
430 		unsigned int count = min(hwreq->req.length - hwreq->req.actual,
431 			(unsigned int)(pages * CI_HDRC_PAGE_SIZE));
432 
433 		ret = add_td_to_list(hwep, hwreq, count, NULL);
434 		if (ret < 0)
435 			return ret;
436 
437 		rest -= count;
438 	}
439 
440 	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
441 	    && (hwreq->req.length % hwep->ep.maxpacket == 0)) {
442 		ret = add_td_to_list(hwep, hwreq, 0, NULL);
443 		if (ret < 0)
444 			return ret;
445 	}
446 
447 	return ret;
448 }
449 
450 static int prepare_td_per_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
451 		struct scatterlist *s)
452 {
453 	unsigned int rest = sg_dma_len(s);
454 	int ret = 0;
455 
456 	hwreq->req.actual = 0;
457 	while (rest > 0) {
458 		unsigned int count = min_t(unsigned int, rest,
459 				CI_MAX_BUF_SIZE);
460 
461 		ret = add_td_to_list(hwep, hwreq, count, s);
462 		if (ret < 0)
463 			return ret;
464 
465 		rest -= count;
466 	}
467 
468 	return ret;
469 }
470 
471 static void ci_add_buffer_entry(struct td_node *node, struct scatterlist *s)
472 {
473 	int empty_td_slot_index = (CI_MAX_BUF_SIZE - node->td_remaining_size)
474 			/ CI_HDRC_PAGE_SIZE;
475 	int i;
476 	u32 token;
477 
478 	token = le32_to_cpu(node->ptr->token) + (sg_dma_len(s) << __ffs(TD_TOTAL_BYTES));
479 	node->ptr->token = cpu_to_le32(token);
480 
481 	for (i = empty_td_slot_index; i < TD_PAGE_COUNT; i++) {
482 		u32 page = (u32) sg_dma_address(s) +
483 			(i - empty_td_slot_index) * CI_HDRC_PAGE_SIZE;
484 
485 		page &= ~TD_RESERVED_MASK;
486 		node->ptr->page[i] = cpu_to_le32(page);
487 	}
488 }
489 
490 static int prepare_td_for_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
491 {
492 	struct usb_request *req = &hwreq->req;
493 	struct scatterlist *s = req->sg;
494 	int ret = 0, i = 0;
495 	struct td_node *node = NULL;
496 
497 	if (!s || req->zero || req->length == 0) {
498 		dev_err(hwep->ci->dev, "not supported operation for sg\n");
499 		return -EINVAL;
500 	}
501 
502 	while (i++ < req->num_mapped_sgs) {
503 		if (sg_dma_address(s) % PAGE_SIZE) {
504 			dev_err(hwep->ci->dev, "not page aligned sg buffer\n");
505 			return -EINVAL;
506 		}
507 
508 		if (node && (node->td_remaining_size >= sg_dma_len(s))) {
509 			ci_add_buffer_entry(node, s);
510 			node->td_remaining_size -= sg_dma_len(s);
511 		} else {
512 			ret = prepare_td_per_sg(hwep, hwreq, s);
513 			if (ret)
514 				return ret;
515 
516 			node = list_entry(hwreq->tds.prev,
517 				struct td_node, td);
518 		}
519 
520 		s = sg_next(s);
521 	}
522 
523 	return ret;
524 }
525 
526 /**
527  * _hardware_enqueue: configures a request at hardware level
528  * @hwep:   endpoint
529  * @hwreq:  request
530  *
531  * This function returns an error code
532  */
533 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
534 {
535 	struct ci_hdrc *ci = hwep->ci;
536 	int ret = 0;
537 	struct td_node *firstnode, *lastnode;
538 
539 	/* don't queue twice */
540 	if (hwreq->req.status == -EALREADY)
541 		return -EALREADY;
542 
543 	hwreq->req.status = -EALREADY;
544 
545 	ret = usb_gadget_map_request_by_dev(ci->dev->parent,
546 					    &hwreq->req, hwep->dir);
547 	if (ret)
548 		return ret;
549 
550 	if (hwreq->req.num_mapped_sgs)
551 		ret = prepare_td_for_sg(hwep, hwreq);
552 	else
553 		ret = prepare_td_for_non_sg(hwep, hwreq);
554 
555 	if (ret)
556 		return ret;
557 
558 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
559 
560 	lastnode = list_entry(hwreq->tds.prev,
561 		struct td_node, td);
562 
563 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
564 	if (!hwreq->req.no_interrupt)
565 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
566 	wmb();
567 
568 	hwreq->req.actual = 0;
569 	if (!list_empty(&hwep->qh.queue)) {
570 		struct ci_hw_req *hwreqprev;
571 		int n = hw_ep_bit(hwep->num, hwep->dir);
572 		int tmp_stat;
573 		struct td_node *prevlastnode;
574 		u32 next = firstnode->dma & TD_ADDR_MASK;
575 
576 		hwreqprev = list_entry(hwep->qh.queue.prev,
577 				struct ci_hw_req, queue);
578 		prevlastnode = list_entry(hwreqprev->tds.prev,
579 				struct td_node, td);
580 
581 		prevlastnode->ptr->next = cpu_to_le32(next);
582 		wmb();
583 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
584 			goto done;
585 		do {
586 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
587 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
588 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
589 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
590 		if (tmp_stat)
591 			goto done;
592 	}
593 
594 	/*  QH configuration */
595 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
596 	hwep->qh.ptr->td.token &=
597 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
598 
599 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
600 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
601 
602 		if (hwreq->req.length == 0
603 				|| hwreq->req.length % hwep->ep.maxpacket)
604 			mul++;
605 		hwep->qh.ptr->cap |= cpu_to_le32(mul << __ffs(QH_MULT));
606 	}
607 
608 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
609 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
610 done:
611 	return ret;
612 }
613 
614 /*
615  * free_pending_td: remove a pending request for the endpoint
616  * @hwep: endpoint
617  */
618 static void free_pending_td(struct ci_hw_ep *hwep)
619 {
620 	struct td_node *pending = hwep->pending_td;
621 
622 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
623 	hwep->pending_td = NULL;
624 	kfree(pending);
625 }
626 
627 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
628 					   struct td_node *node)
629 {
630 	hwep->qh.ptr->td.next = cpu_to_le32(node->dma);
631 	hwep->qh.ptr->td.token &=
632 		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
633 
634 	return hw_ep_prime(ci, hwep->num, hwep->dir,
635 				hwep->type == USB_ENDPOINT_XFER_CONTROL);
636 }
637 
638 /**
639  * _hardware_dequeue: handles a request at hardware level
640  * @gadget: gadget
641  * @hwep:   endpoint
642  *
643  * This function returns an error code
644  */
645 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
646 {
647 	u32 tmptoken;
648 	struct td_node *node, *tmpnode;
649 	unsigned remaining_length;
650 	unsigned actual = hwreq->req.length;
651 	struct ci_hdrc *ci = hwep->ci;
652 
653 	if (hwreq->req.status != -EALREADY)
654 		return -EINVAL;
655 
656 	hwreq->req.status = 0;
657 
658 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
659 		tmptoken = le32_to_cpu(node->ptr->token);
660 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
661 			int n = hw_ep_bit(hwep->num, hwep->dir);
662 
663 			if (ci->rev == CI_REVISION_24)
664 				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
665 					reprime_dtd(ci, hwep, node);
666 			hwreq->req.status = -EALREADY;
667 			return -EBUSY;
668 		}
669 
670 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
671 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
672 		actual -= remaining_length;
673 
674 		hwreq->req.status = tmptoken & TD_STATUS;
675 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
676 			hwreq->req.status = -EPIPE;
677 			break;
678 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
679 			hwreq->req.status = -EPROTO;
680 			break;
681 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
682 			hwreq->req.status = -EILSEQ;
683 			break;
684 		}
685 
686 		if (remaining_length) {
687 			if (hwep->dir == TX) {
688 				hwreq->req.status = -EPROTO;
689 				break;
690 			}
691 		}
692 		/*
693 		 * As the hardware could still address the freed td
694 		 * which will run the udc unusable, the cleanup of the
695 		 * td has to be delayed by one.
696 		 */
697 		if (hwep->pending_td)
698 			free_pending_td(hwep);
699 
700 		hwep->pending_td = node;
701 		list_del_init(&node->td);
702 	}
703 
704 	usb_gadget_unmap_request_by_dev(hwep->ci->dev->parent,
705 					&hwreq->req, hwep->dir);
706 
707 	hwreq->req.actual += actual;
708 
709 	if (hwreq->req.status)
710 		return hwreq->req.status;
711 
712 	return hwreq->req.actual;
713 }
714 
715 /**
716  * _ep_nuke: dequeues all endpoint requests
717  * @hwep: endpoint
718  *
719  * This function returns an error code
720  * Caller must hold lock
721  */
722 static int _ep_nuke(struct ci_hw_ep *hwep)
723 __releases(hwep->lock)
724 __acquires(hwep->lock)
725 {
726 	struct td_node *node, *tmpnode;
727 	if (hwep == NULL)
728 		return -EINVAL;
729 
730 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
731 
732 	while (!list_empty(&hwep->qh.queue)) {
733 
734 		/* pop oldest request */
735 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
736 						     struct ci_hw_req, queue);
737 
738 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
739 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
740 			list_del_init(&node->td);
741 			node->ptr = NULL;
742 			kfree(node);
743 		}
744 
745 		list_del_init(&hwreq->queue);
746 		hwreq->req.status = -ESHUTDOWN;
747 
748 		if (hwreq->req.complete != NULL) {
749 			spin_unlock(hwep->lock);
750 			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
751 			spin_lock(hwep->lock);
752 		}
753 	}
754 
755 	if (hwep->pending_td)
756 		free_pending_td(hwep);
757 
758 	return 0;
759 }
760 
761 static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
762 {
763 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
764 	int direction, retval = 0;
765 	unsigned long flags;
766 
767 	if (ep == NULL || hwep->ep.desc == NULL)
768 		return -EINVAL;
769 
770 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
771 		return -EOPNOTSUPP;
772 
773 	spin_lock_irqsave(hwep->lock, flags);
774 
775 	if (value && hwep->dir == TX && check_transfer &&
776 		!list_empty(&hwep->qh.queue) &&
777 			!usb_endpoint_xfer_control(hwep->ep.desc)) {
778 		spin_unlock_irqrestore(hwep->lock, flags);
779 		return -EAGAIN;
780 	}
781 
782 	direction = hwep->dir;
783 	do {
784 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
785 
786 		if (!value)
787 			hwep->wedge = 0;
788 
789 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
790 			hwep->dir = (hwep->dir == TX) ? RX : TX;
791 
792 	} while (hwep->dir != direction);
793 
794 	spin_unlock_irqrestore(hwep->lock, flags);
795 	return retval;
796 }
797 
798 
799 /**
800  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
801  * @gadget: gadget
802  *
803  * This function returns an error code
804  */
805 static int _gadget_stop_activity(struct usb_gadget *gadget)
806 {
807 	struct usb_ep *ep;
808 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
809 	unsigned long flags;
810 
811 	/* flush all endpoints */
812 	gadget_for_each_ep(ep, gadget) {
813 		usb_ep_fifo_flush(ep);
814 	}
815 	usb_ep_fifo_flush(&ci->ep0out->ep);
816 	usb_ep_fifo_flush(&ci->ep0in->ep);
817 
818 	/* make sure to disable all endpoints */
819 	gadget_for_each_ep(ep, gadget) {
820 		usb_ep_disable(ep);
821 	}
822 
823 	if (ci->status != NULL) {
824 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
825 		ci->status = NULL;
826 	}
827 
828 	spin_lock_irqsave(&ci->lock, flags);
829 	ci->gadget.speed = USB_SPEED_UNKNOWN;
830 	ci->remote_wakeup = 0;
831 	ci->suspended = 0;
832 	spin_unlock_irqrestore(&ci->lock, flags);
833 
834 	return 0;
835 }
836 
837 /******************************************************************************
838  * ISR block
839  *****************************************************************************/
840 /**
841  * isr_reset_handler: USB reset interrupt handler
842  * @ci: UDC device
843  *
844  * This function resets USB engine after a bus reset occurred
845  */
846 static void isr_reset_handler(struct ci_hdrc *ci)
847 __releases(ci->lock)
848 __acquires(ci->lock)
849 {
850 	int retval;
851 
852 	spin_unlock(&ci->lock);
853 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
854 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
855 
856 	retval = _gadget_stop_activity(&ci->gadget);
857 	if (retval)
858 		goto done;
859 
860 	retval = hw_usb_reset(ci);
861 	if (retval)
862 		goto done;
863 
864 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
865 	if (ci->status == NULL)
866 		retval = -ENOMEM;
867 
868 done:
869 	spin_lock(&ci->lock);
870 
871 	if (retval)
872 		dev_err(ci->dev, "error: %i\n", retval);
873 }
874 
875 /**
876  * isr_get_status_complete: get_status request complete function
877  * @ep:  endpoint
878  * @req: request handled
879  *
880  * Caller must release lock
881  */
882 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
883 {
884 	if (ep == NULL || req == NULL)
885 		return;
886 
887 	kfree(req->buf);
888 	usb_ep_free_request(ep, req);
889 }
890 
891 /**
892  * _ep_queue: queues (submits) an I/O request to an endpoint
893  * @ep:        endpoint
894  * @req:       request
895  * @gfp_flags: GFP flags (not used)
896  *
897  * Caller must hold lock
898  * This function returns an error code
899  */
900 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
901 		    gfp_t __maybe_unused gfp_flags)
902 {
903 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
904 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
905 	struct ci_hdrc *ci = hwep->ci;
906 	int retval = 0;
907 
908 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
909 		return -EINVAL;
910 
911 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
912 		if (req->length)
913 			hwep = (ci->ep0_dir == RX) ?
914 			       ci->ep0out : ci->ep0in;
915 		if (!list_empty(&hwep->qh.queue)) {
916 			_ep_nuke(hwep);
917 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
918 				 _usb_addr(hwep));
919 		}
920 	}
921 
922 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
923 	    hwreq->req.length > hwep->ep.mult * hwep->ep.maxpacket) {
924 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
925 		return -EMSGSIZE;
926 	}
927 
928 	/* first nuke then test link, e.g. previous status has not sent */
929 	if (!list_empty(&hwreq->queue)) {
930 		dev_err(hwep->ci->dev, "request already in queue\n");
931 		return -EBUSY;
932 	}
933 
934 	/* push request */
935 	hwreq->req.status = -EINPROGRESS;
936 	hwreq->req.actual = 0;
937 
938 	retval = _hardware_enqueue(hwep, hwreq);
939 
940 	if (retval == -EALREADY)
941 		retval = 0;
942 	if (!retval)
943 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
944 
945 	return retval;
946 }
947 
948 /**
949  * isr_get_status_response: get_status request response
950  * @ci: ci struct
951  * @setup: setup request packet
952  *
953  * This function returns an error code
954  */
955 static int isr_get_status_response(struct ci_hdrc *ci,
956 				   struct usb_ctrlrequest *setup)
957 __releases(hwep->lock)
958 __acquires(hwep->lock)
959 {
960 	struct ci_hw_ep *hwep = ci->ep0in;
961 	struct usb_request *req = NULL;
962 	gfp_t gfp_flags = GFP_ATOMIC;
963 	int dir, num, retval;
964 
965 	if (hwep == NULL || setup == NULL)
966 		return -EINVAL;
967 
968 	spin_unlock(hwep->lock);
969 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
970 	spin_lock(hwep->lock);
971 	if (req == NULL)
972 		return -ENOMEM;
973 
974 	req->complete = isr_get_status_complete;
975 	req->length   = 2;
976 	req->buf      = kzalloc(req->length, gfp_flags);
977 	if (req->buf == NULL) {
978 		retval = -ENOMEM;
979 		goto err_free_req;
980 	}
981 
982 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
983 		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
984 			ci->gadget.is_selfpowered;
985 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
986 		   == USB_RECIP_ENDPOINT) {
987 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
988 			TX : RX;
989 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
990 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
991 	}
992 	/* else do nothing; reserved for future use */
993 
994 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
995 	if (retval)
996 		goto err_free_buf;
997 
998 	return 0;
999 
1000  err_free_buf:
1001 	kfree(req->buf);
1002  err_free_req:
1003 	spin_unlock(hwep->lock);
1004 	usb_ep_free_request(&hwep->ep, req);
1005 	spin_lock(hwep->lock);
1006 	return retval;
1007 }
1008 
1009 /**
1010  * isr_setup_status_complete: setup_status request complete function
1011  * @ep:  endpoint
1012  * @req: request handled
1013  *
1014  * Caller must release lock. Put the port in test mode if test mode
1015  * feature is selected.
1016  */
1017 static void
1018 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
1019 {
1020 	struct ci_hdrc *ci = req->context;
1021 	unsigned long flags;
1022 
1023 	if (ci->setaddr) {
1024 		hw_usb_set_address(ci, ci->address);
1025 		ci->setaddr = false;
1026 		if (ci->address)
1027 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
1028 	}
1029 
1030 	spin_lock_irqsave(&ci->lock, flags);
1031 	if (ci->test_mode)
1032 		hw_port_test_set(ci, ci->test_mode);
1033 	spin_unlock_irqrestore(&ci->lock, flags);
1034 }
1035 
1036 /**
1037  * isr_setup_status_phase: queues the status phase of a setup transation
1038  * @ci: ci struct
1039  *
1040  * This function returns an error code
1041  */
1042 static int isr_setup_status_phase(struct ci_hdrc *ci)
1043 {
1044 	struct ci_hw_ep *hwep;
1045 
1046 	/*
1047 	 * Unexpected USB controller behavior, caused by bad signal integrity
1048 	 * or ground reference problems, can lead to isr_setup_status_phase
1049 	 * being called with ci->status equal to NULL.
1050 	 * If this situation occurs, you should review your USB hardware design.
1051 	 */
1052 	if (WARN_ON_ONCE(!ci->status))
1053 		return -EPIPE;
1054 
1055 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
1056 	ci->status->context = ci;
1057 	ci->status->complete = isr_setup_status_complete;
1058 
1059 	return _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
1060 }
1061 
1062 /**
1063  * isr_tr_complete_low: transaction complete low level handler
1064  * @hwep: endpoint
1065  *
1066  * This function returns an error code
1067  * Caller must hold lock
1068  */
1069 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
1070 __releases(hwep->lock)
1071 __acquires(hwep->lock)
1072 {
1073 	struct ci_hw_req *hwreq, *hwreqtemp;
1074 	struct ci_hw_ep *hweptemp = hwep;
1075 	int retval = 0;
1076 
1077 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
1078 			queue) {
1079 		retval = _hardware_dequeue(hwep, hwreq);
1080 		if (retval < 0)
1081 			break;
1082 		list_del_init(&hwreq->queue);
1083 		if (hwreq->req.complete != NULL) {
1084 			spin_unlock(hwep->lock);
1085 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
1086 					hwreq->req.length)
1087 				hweptemp = hwep->ci->ep0in;
1088 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
1089 			spin_lock(hwep->lock);
1090 		}
1091 	}
1092 
1093 	if (retval == -EBUSY)
1094 		retval = 0;
1095 
1096 	return retval;
1097 }
1098 
1099 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
1100 {
1101 	dev_warn(&ci->gadget.dev,
1102 		"connect the device to an alternate port if you want HNP\n");
1103 	return isr_setup_status_phase(ci);
1104 }
1105 
1106 /**
1107  * isr_setup_packet_handler: setup packet handler
1108  * @ci: UDC descriptor
1109  *
1110  * This function handles setup packet
1111  */
1112 static void isr_setup_packet_handler(struct ci_hdrc *ci)
1113 __releases(ci->lock)
1114 __acquires(ci->lock)
1115 {
1116 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1117 	struct usb_ctrlrequest req;
1118 	int type, num, dir, err = -EINVAL;
1119 	u8 tmode = 0;
1120 
1121 	/*
1122 	 * Flush data and handshake transactions of previous
1123 	 * setup packet.
1124 	 */
1125 	_ep_nuke(ci->ep0out);
1126 	_ep_nuke(ci->ep0in);
1127 
1128 	/* read_setup_packet */
1129 	do {
1130 		hw_test_and_set_setup_guard(ci);
1131 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1132 	} while (!hw_test_and_clear_setup_guard(ci));
1133 
1134 	type = req.bRequestType;
1135 
1136 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1137 
1138 	switch (req.bRequest) {
1139 	case USB_REQ_CLEAR_FEATURE:
1140 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1141 				le16_to_cpu(req.wValue) ==
1142 				USB_ENDPOINT_HALT) {
1143 			if (req.wLength != 0)
1144 				break;
1145 			num  = le16_to_cpu(req.wIndex);
1146 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1147 			num &= USB_ENDPOINT_NUMBER_MASK;
1148 			if (dir == TX)
1149 				num += ci->hw_ep_max / 2;
1150 			if (!ci->ci_hw_ep[num].wedge) {
1151 				spin_unlock(&ci->lock);
1152 				err = usb_ep_clear_halt(
1153 					&ci->ci_hw_ep[num].ep);
1154 				spin_lock(&ci->lock);
1155 				if (err)
1156 					break;
1157 			}
1158 			err = isr_setup_status_phase(ci);
1159 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1160 				le16_to_cpu(req.wValue) ==
1161 				USB_DEVICE_REMOTE_WAKEUP) {
1162 			if (req.wLength != 0)
1163 				break;
1164 			ci->remote_wakeup = 0;
1165 			err = isr_setup_status_phase(ci);
1166 		} else {
1167 			goto delegate;
1168 		}
1169 		break;
1170 	case USB_REQ_GET_STATUS:
1171 		if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
1172 			le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
1173 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1174 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1175 			goto delegate;
1176 		if (le16_to_cpu(req.wLength) != 2 ||
1177 		    le16_to_cpu(req.wValue)  != 0)
1178 			break;
1179 		err = isr_get_status_response(ci, &req);
1180 		break;
1181 	case USB_REQ_SET_ADDRESS:
1182 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1183 			goto delegate;
1184 		if (le16_to_cpu(req.wLength) != 0 ||
1185 		    le16_to_cpu(req.wIndex)  != 0)
1186 			break;
1187 		ci->address = (u8)le16_to_cpu(req.wValue);
1188 		ci->setaddr = true;
1189 		err = isr_setup_status_phase(ci);
1190 		break;
1191 	case USB_REQ_SET_FEATURE:
1192 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1193 				le16_to_cpu(req.wValue) ==
1194 				USB_ENDPOINT_HALT) {
1195 			if (req.wLength != 0)
1196 				break;
1197 			num  = le16_to_cpu(req.wIndex);
1198 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1199 			num &= USB_ENDPOINT_NUMBER_MASK;
1200 			if (dir == TX)
1201 				num += ci->hw_ep_max / 2;
1202 
1203 			spin_unlock(&ci->lock);
1204 			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1205 			spin_lock(&ci->lock);
1206 			if (!err)
1207 				isr_setup_status_phase(ci);
1208 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1209 			if (req.wLength != 0)
1210 				break;
1211 			switch (le16_to_cpu(req.wValue)) {
1212 			case USB_DEVICE_REMOTE_WAKEUP:
1213 				ci->remote_wakeup = 1;
1214 				err = isr_setup_status_phase(ci);
1215 				break;
1216 			case USB_DEVICE_TEST_MODE:
1217 				tmode = le16_to_cpu(req.wIndex) >> 8;
1218 				switch (tmode) {
1219 				case TEST_J:
1220 				case TEST_K:
1221 				case TEST_SE0_NAK:
1222 				case TEST_PACKET:
1223 				case TEST_FORCE_EN:
1224 					ci->test_mode = tmode;
1225 					err = isr_setup_status_phase(
1226 							ci);
1227 					break;
1228 				default:
1229 					break;
1230 				}
1231 				break;
1232 			case USB_DEVICE_B_HNP_ENABLE:
1233 				if (ci_otg_is_fsm_mode(ci)) {
1234 					ci->gadget.b_hnp_enable = 1;
1235 					err = isr_setup_status_phase(
1236 							ci);
1237 				}
1238 				break;
1239 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1240 				if (ci_otg_is_fsm_mode(ci))
1241 					err = otg_a_alt_hnp_support(ci);
1242 				break;
1243 			case USB_DEVICE_A_HNP_SUPPORT:
1244 				if (ci_otg_is_fsm_mode(ci)) {
1245 					ci->gadget.a_hnp_support = 1;
1246 					err = isr_setup_status_phase(
1247 							ci);
1248 				}
1249 				break;
1250 			default:
1251 				goto delegate;
1252 			}
1253 		} else {
1254 			goto delegate;
1255 		}
1256 		break;
1257 	default:
1258 delegate:
1259 		if (req.wLength == 0)   /* no data phase */
1260 			ci->ep0_dir = TX;
1261 
1262 		spin_unlock(&ci->lock);
1263 		err = ci->driver->setup(&ci->gadget, &req);
1264 		spin_lock(&ci->lock);
1265 		break;
1266 	}
1267 
1268 	if (err < 0) {
1269 		spin_unlock(&ci->lock);
1270 		if (_ep_set_halt(&hwep->ep, 1, false))
1271 			dev_err(ci->dev, "error: _ep_set_halt\n");
1272 		spin_lock(&ci->lock);
1273 	}
1274 }
1275 
1276 /**
1277  * isr_tr_complete_handler: transaction complete interrupt handler
1278  * @ci: UDC descriptor
1279  *
1280  * This function handles traffic events
1281  */
1282 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1283 __releases(ci->lock)
1284 __acquires(ci->lock)
1285 {
1286 	unsigned i;
1287 	int err;
1288 
1289 	for (i = 0; i < ci->hw_ep_max; i++) {
1290 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1291 
1292 		if (hwep->ep.desc == NULL)
1293 			continue;   /* not configured */
1294 
1295 		if (hw_test_and_clear_complete(ci, i)) {
1296 			err = isr_tr_complete_low(hwep);
1297 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1298 				if (err > 0)   /* needs status phase */
1299 					err = isr_setup_status_phase(ci);
1300 				if (err < 0) {
1301 					spin_unlock(&ci->lock);
1302 					if (_ep_set_halt(&hwep->ep, 1, false))
1303 						dev_err(ci->dev,
1304 						"error: _ep_set_halt\n");
1305 					spin_lock(&ci->lock);
1306 				}
1307 			}
1308 		}
1309 
1310 		/* Only handle setup packet below */
1311 		if (i == 0 &&
1312 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1313 			isr_setup_packet_handler(ci);
1314 	}
1315 }
1316 
1317 /******************************************************************************
1318  * ENDPT block
1319  *****************************************************************************/
1320 /**
1321  * ep_enable: configure endpoint, making it usable
1322  *
1323  * Check usb_ep_enable() at "usb_gadget.h" for details
1324  */
1325 static int ep_enable(struct usb_ep *ep,
1326 		     const struct usb_endpoint_descriptor *desc)
1327 {
1328 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1329 	int retval = 0;
1330 	unsigned long flags;
1331 	u32 cap = 0;
1332 
1333 	if (ep == NULL || desc == NULL)
1334 		return -EINVAL;
1335 
1336 	spin_lock_irqsave(hwep->lock, flags);
1337 
1338 	/* only internal SW should enable ctrl endpts */
1339 
1340 	if (!list_empty(&hwep->qh.queue)) {
1341 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1342 		spin_unlock_irqrestore(hwep->lock, flags);
1343 		return -EBUSY;
1344 	}
1345 
1346 	hwep->ep.desc = desc;
1347 
1348 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1349 	hwep->num  = usb_endpoint_num(desc);
1350 	hwep->type = usb_endpoint_type(desc);
1351 
1352 	hwep->ep.maxpacket = usb_endpoint_maxp(desc);
1353 	hwep->ep.mult = usb_endpoint_maxp_mult(desc);
1354 
1355 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1356 		cap |= QH_IOS;
1357 
1358 	cap |= QH_ZLT;
1359 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1360 	/*
1361 	 * For ISO-TX, we set mult at QH as the largest value, and use
1362 	 * MultO at TD as real mult value.
1363 	 */
1364 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1365 		cap |= 3 << __ffs(QH_MULT);
1366 
1367 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1368 
1369 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1370 
1371 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1372 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1373 		retval = -EINVAL;
1374 	}
1375 
1376 	/*
1377 	 * Enable endpoints in the HW other than ep0 as ep0
1378 	 * is always enabled
1379 	 */
1380 	if (hwep->num)
1381 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1382 				       hwep->type);
1383 
1384 	spin_unlock_irqrestore(hwep->lock, flags);
1385 	return retval;
1386 }
1387 
1388 /**
1389  * ep_disable: endpoint is no longer usable
1390  *
1391  * Check usb_ep_disable() at "usb_gadget.h" for details
1392  */
1393 static int ep_disable(struct usb_ep *ep)
1394 {
1395 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1396 	int direction, retval = 0;
1397 	unsigned long flags;
1398 
1399 	if (ep == NULL)
1400 		return -EINVAL;
1401 	else if (hwep->ep.desc == NULL)
1402 		return -EBUSY;
1403 
1404 	spin_lock_irqsave(hwep->lock, flags);
1405 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1406 		spin_unlock_irqrestore(hwep->lock, flags);
1407 		return 0;
1408 	}
1409 
1410 	/* only internal SW should disable ctrl endpts */
1411 
1412 	direction = hwep->dir;
1413 	do {
1414 		retval |= _ep_nuke(hwep);
1415 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1416 
1417 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1418 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1419 
1420 	} while (hwep->dir != direction);
1421 
1422 	hwep->ep.desc = NULL;
1423 
1424 	spin_unlock_irqrestore(hwep->lock, flags);
1425 	return retval;
1426 }
1427 
1428 /**
1429  * ep_alloc_request: allocate a request object to use with this endpoint
1430  *
1431  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1432  */
1433 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1434 {
1435 	struct ci_hw_req *hwreq = NULL;
1436 
1437 	if (ep == NULL)
1438 		return NULL;
1439 
1440 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1441 	if (hwreq != NULL) {
1442 		INIT_LIST_HEAD(&hwreq->queue);
1443 		INIT_LIST_HEAD(&hwreq->tds);
1444 	}
1445 
1446 	return (hwreq == NULL) ? NULL : &hwreq->req;
1447 }
1448 
1449 /**
1450  * ep_free_request: frees a request object
1451  *
1452  * Check usb_ep_free_request() at "usb_gadget.h" for details
1453  */
1454 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1455 {
1456 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1457 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1458 	struct td_node *node, *tmpnode;
1459 	unsigned long flags;
1460 
1461 	if (ep == NULL || req == NULL) {
1462 		return;
1463 	} else if (!list_empty(&hwreq->queue)) {
1464 		dev_err(hwep->ci->dev, "freeing queued request\n");
1465 		return;
1466 	}
1467 
1468 	spin_lock_irqsave(hwep->lock, flags);
1469 
1470 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1471 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1472 		list_del_init(&node->td);
1473 		node->ptr = NULL;
1474 		kfree(node);
1475 	}
1476 
1477 	kfree(hwreq);
1478 
1479 	spin_unlock_irqrestore(hwep->lock, flags);
1480 }
1481 
1482 /**
1483  * ep_queue: queues (submits) an I/O request to an endpoint
1484  *
1485  * Check usb_ep_queue()* at usb_gadget.h" for details
1486  */
1487 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1488 		    gfp_t __maybe_unused gfp_flags)
1489 {
1490 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1491 	int retval = 0;
1492 	unsigned long flags;
1493 
1494 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1495 		return -EINVAL;
1496 
1497 	spin_lock_irqsave(hwep->lock, flags);
1498 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1499 		spin_unlock_irqrestore(hwep->lock, flags);
1500 		return 0;
1501 	}
1502 	retval = _ep_queue(ep, req, gfp_flags);
1503 	spin_unlock_irqrestore(hwep->lock, flags);
1504 	return retval;
1505 }
1506 
1507 /**
1508  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1509  *
1510  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1511  */
1512 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1513 {
1514 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1515 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1516 	unsigned long flags;
1517 	struct td_node *node, *tmpnode;
1518 
1519 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1520 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1521 		list_empty(&hwep->qh.queue))
1522 		return -EINVAL;
1523 
1524 	spin_lock_irqsave(hwep->lock, flags);
1525 	if (hwep->ci->gadget.speed != USB_SPEED_UNKNOWN)
1526 		hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1527 
1528 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1529 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1530 		list_del(&node->td);
1531 		kfree(node);
1532 	}
1533 
1534 	/* pop request */
1535 	list_del_init(&hwreq->queue);
1536 
1537 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1538 
1539 	req->status = -ECONNRESET;
1540 
1541 	if (hwreq->req.complete != NULL) {
1542 		spin_unlock(hwep->lock);
1543 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1544 		spin_lock(hwep->lock);
1545 	}
1546 
1547 	spin_unlock_irqrestore(hwep->lock, flags);
1548 	return 0;
1549 }
1550 
1551 /**
1552  * ep_set_halt: sets the endpoint halt feature
1553  *
1554  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1555  */
1556 static int ep_set_halt(struct usb_ep *ep, int value)
1557 {
1558 	return _ep_set_halt(ep, value, true);
1559 }
1560 
1561 /**
1562  * ep_set_wedge: sets the halt feature and ignores clear requests
1563  *
1564  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1565  */
1566 static int ep_set_wedge(struct usb_ep *ep)
1567 {
1568 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1569 	unsigned long flags;
1570 
1571 	if (ep == NULL || hwep->ep.desc == NULL)
1572 		return -EINVAL;
1573 
1574 	spin_lock_irqsave(hwep->lock, flags);
1575 	hwep->wedge = 1;
1576 	spin_unlock_irqrestore(hwep->lock, flags);
1577 
1578 	return usb_ep_set_halt(ep);
1579 }
1580 
1581 /**
1582  * ep_fifo_flush: flushes contents of a fifo
1583  *
1584  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1585  */
1586 static void ep_fifo_flush(struct usb_ep *ep)
1587 {
1588 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1589 	unsigned long flags;
1590 
1591 	if (ep == NULL) {
1592 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1593 		return;
1594 	}
1595 
1596 	spin_lock_irqsave(hwep->lock, flags);
1597 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1598 		spin_unlock_irqrestore(hwep->lock, flags);
1599 		return;
1600 	}
1601 
1602 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1603 
1604 	spin_unlock_irqrestore(hwep->lock, flags);
1605 }
1606 
1607 /**
1608  * Endpoint-specific part of the API to the USB controller hardware
1609  * Check "usb_gadget.h" for details
1610  */
1611 static const struct usb_ep_ops usb_ep_ops = {
1612 	.enable	       = ep_enable,
1613 	.disable       = ep_disable,
1614 	.alloc_request = ep_alloc_request,
1615 	.free_request  = ep_free_request,
1616 	.queue	       = ep_queue,
1617 	.dequeue       = ep_dequeue,
1618 	.set_halt      = ep_set_halt,
1619 	.set_wedge     = ep_set_wedge,
1620 	.fifo_flush    = ep_fifo_flush,
1621 };
1622 
1623 /******************************************************************************
1624  * GADGET block
1625  *****************************************************************************/
1626 /**
1627  * ci_hdrc_gadget_connect: caller makes sure gadget driver is binded
1628  */
1629 static void ci_hdrc_gadget_connect(struct usb_gadget *_gadget, int is_active)
1630 {
1631 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1632 
1633 	if (is_active) {
1634 		pm_runtime_get_sync(ci->dev);
1635 		hw_device_reset(ci);
1636 		spin_lock_irq(&ci->lock);
1637 		if (ci->driver) {
1638 			hw_device_state(ci, ci->ep0out->qh.dma);
1639 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1640 			spin_unlock_irq(&ci->lock);
1641 			usb_udc_vbus_handler(_gadget, true);
1642 		} else {
1643 			spin_unlock_irq(&ci->lock);
1644 		}
1645 	} else {
1646 		usb_udc_vbus_handler(_gadget, false);
1647 		if (ci->driver)
1648 			ci->driver->disconnect(&ci->gadget);
1649 		hw_device_state(ci, 0);
1650 		if (ci->platdata->notify_event)
1651 			ci->platdata->notify_event(ci,
1652 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1653 		_gadget_stop_activity(&ci->gadget);
1654 		pm_runtime_put_sync(ci->dev);
1655 		usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1656 	}
1657 }
1658 
1659 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1660 {
1661 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1662 	unsigned long flags;
1663 	int ret = 0;
1664 
1665 	spin_lock_irqsave(&ci->lock, flags);
1666 	ci->vbus_active = is_active;
1667 	spin_unlock_irqrestore(&ci->lock, flags);
1668 
1669 	if (ci->usb_phy)
1670 		usb_phy_set_charger_state(ci->usb_phy, is_active ?
1671 			USB_CHARGER_PRESENT : USB_CHARGER_ABSENT);
1672 
1673 	if (ci->platdata->notify_event)
1674 		ret = ci->platdata->notify_event(ci,
1675 				CI_HDRC_CONTROLLER_VBUS_EVENT);
1676 
1677 	if (ci->driver)
1678 		ci_hdrc_gadget_connect(_gadget, is_active);
1679 
1680 	return ret;
1681 }
1682 
1683 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1684 {
1685 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1686 	unsigned long flags;
1687 	int ret = 0;
1688 
1689 	spin_lock_irqsave(&ci->lock, flags);
1690 	if (ci->gadget.speed == USB_SPEED_UNKNOWN) {
1691 		spin_unlock_irqrestore(&ci->lock, flags);
1692 		return 0;
1693 	}
1694 	if (!ci->remote_wakeup) {
1695 		ret = -EOPNOTSUPP;
1696 		goto out;
1697 	}
1698 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1699 		ret = -EINVAL;
1700 		goto out;
1701 	}
1702 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1703 out:
1704 	spin_unlock_irqrestore(&ci->lock, flags);
1705 	return ret;
1706 }
1707 
1708 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1709 {
1710 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1711 
1712 	if (ci->usb_phy)
1713 		return usb_phy_set_power(ci->usb_phy, ma);
1714 	return -ENOTSUPP;
1715 }
1716 
1717 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1718 {
1719 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1720 	struct ci_hw_ep *hwep = ci->ep0in;
1721 	unsigned long flags;
1722 
1723 	spin_lock_irqsave(hwep->lock, flags);
1724 	_gadget->is_selfpowered = (is_on != 0);
1725 	spin_unlock_irqrestore(hwep->lock, flags);
1726 
1727 	return 0;
1728 }
1729 
1730 /* Change Data+ pullup status
1731  * this func is used by usb_gadget_connect/disconnect
1732  */
1733 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1734 {
1735 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1736 
1737 	/*
1738 	 * Data+ pullup controlled by OTG state machine in OTG fsm mode;
1739 	 * and don't touch Data+ in host mode for dual role config.
1740 	 */
1741 	if (ci_otg_is_fsm_mode(ci) || ci->role == CI_ROLE_HOST)
1742 		return 0;
1743 
1744 	pm_runtime_get_sync(ci->dev);
1745 	if (is_on)
1746 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1747 	else
1748 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1749 	pm_runtime_put_sync(ci->dev);
1750 
1751 	return 0;
1752 }
1753 
1754 static int ci_udc_start(struct usb_gadget *gadget,
1755 			 struct usb_gadget_driver *driver);
1756 static int ci_udc_stop(struct usb_gadget *gadget);
1757 
1758 /* Match ISOC IN from the highest endpoint */
1759 static struct usb_ep *ci_udc_match_ep(struct usb_gadget *gadget,
1760 			      struct usb_endpoint_descriptor *desc,
1761 			      struct usb_ss_ep_comp_descriptor *comp_desc)
1762 {
1763 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1764 	struct usb_ep *ep;
1765 
1766 	if (usb_endpoint_xfer_isoc(desc) && usb_endpoint_dir_in(desc)) {
1767 		list_for_each_entry_reverse(ep, &ci->gadget.ep_list, ep_list) {
1768 			if (ep->caps.dir_in && !ep->claimed)
1769 				return ep;
1770 		}
1771 	}
1772 
1773 	return NULL;
1774 }
1775 
1776 /**
1777  * Device operations part of the API to the USB controller hardware,
1778  * which don't involve endpoints (or i/o)
1779  * Check  "usb_gadget.h" for details
1780  */
1781 static const struct usb_gadget_ops usb_gadget_ops = {
1782 	.vbus_session	= ci_udc_vbus_session,
1783 	.wakeup		= ci_udc_wakeup,
1784 	.set_selfpowered	= ci_udc_selfpowered,
1785 	.pullup		= ci_udc_pullup,
1786 	.vbus_draw	= ci_udc_vbus_draw,
1787 	.udc_start	= ci_udc_start,
1788 	.udc_stop	= ci_udc_stop,
1789 	.match_ep 	= ci_udc_match_ep,
1790 };
1791 
1792 static int init_eps(struct ci_hdrc *ci)
1793 {
1794 	int retval = 0, i, j;
1795 
1796 	for (i = 0; i < ci->hw_ep_max/2; i++)
1797 		for (j = RX; j <= TX; j++) {
1798 			int k = i + j * ci->hw_ep_max/2;
1799 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1800 
1801 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1802 					(j == TX)  ? "in" : "out");
1803 
1804 			hwep->ci          = ci;
1805 			hwep->lock         = &ci->lock;
1806 			hwep->td_pool      = ci->td_pool;
1807 
1808 			hwep->ep.name      = hwep->name;
1809 			hwep->ep.ops       = &usb_ep_ops;
1810 
1811 			if (i == 0) {
1812 				hwep->ep.caps.type_control = true;
1813 			} else {
1814 				hwep->ep.caps.type_iso = true;
1815 				hwep->ep.caps.type_bulk = true;
1816 				hwep->ep.caps.type_int = true;
1817 			}
1818 
1819 			if (j == TX)
1820 				hwep->ep.caps.dir_in = true;
1821 			else
1822 				hwep->ep.caps.dir_out = true;
1823 
1824 			/*
1825 			 * for ep0: maxP defined in desc, for other
1826 			 * eps, maxP is set by epautoconfig() called
1827 			 * by gadget layer
1828 			 */
1829 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1830 
1831 			INIT_LIST_HEAD(&hwep->qh.queue);
1832 			hwep->qh.ptr = dma_pool_zalloc(ci->qh_pool, GFP_KERNEL,
1833 						       &hwep->qh.dma);
1834 			if (hwep->qh.ptr == NULL)
1835 				retval = -ENOMEM;
1836 
1837 			/*
1838 			 * set up shorthands for ep0 out and in endpoints,
1839 			 * don't add to gadget's ep_list
1840 			 */
1841 			if (i == 0) {
1842 				if (j == RX)
1843 					ci->ep0out = hwep;
1844 				else
1845 					ci->ep0in = hwep;
1846 
1847 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1848 				continue;
1849 			}
1850 
1851 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1852 		}
1853 
1854 	return retval;
1855 }
1856 
1857 static void destroy_eps(struct ci_hdrc *ci)
1858 {
1859 	int i;
1860 
1861 	for (i = 0; i < ci->hw_ep_max; i++) {
1862 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1863 
1864 		if (hwep->pending_td)
1865 			free_pending_td(hwep);
1866 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1867 	}
1868 }
1869 
1870 /**
1871  * ci_udc_start: register a gadget driver
1872  * @gadget: our gadget
1873  * @driver: the driver being registered
1874  *
1875  * Interrupts are enabled here.
1876  */
1877 static int ci_udc_start(struct usb_gadget *gadget,
1878 			 struct usb_gadget_driver *driver)
1879 {
1880 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1881 	int retval;
1882 
1883 	if (driver->disconnect == NULL)
1884 		return -EINVAL;
1885 
1886 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1887 	retval = usb_ep_enable(&ci->ep0out->ep);
1888 	if (retval)
1889 		return retval;
1890 
1891 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1892 	retval = usb_ep_enable(&ci->ep0in->ep);
1893 	if (retval)
1894 		return retval;
1895 
1896 	ci->driver = driver;
1897 
1898 	/* Start otg fsm for B-device */
1899 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1900 		ci_hdrc_otg_fsm_start(ci);
1901 		return retval;
1902 	}
1903 
1904 	if (ci->vbus_active)
1905 		ci_hdrc_gadget_connect(gadget, 1);
1906 	else
1907 		usb_udc_vbus_handler(&ci->gadget, false);
1908 
1909 	return retval;
1910 }
1911 
1912 static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
1913 {
1914 	if (!ci_otg_is_fsm_mode(ci))
1915 		return;
1916 
1917 	mutex_lock(&ci->fsm.lock);
1918 	if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
1919 		ci->fsm.a_bidl_adis_tmout = 1;
1920 		ci_hdrc_otg_fsm_start(ci);
1921 	} else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
1922 		ci->fsm.protocol = PROTO_UNDEF;
1923 		ci->fsm.otg->state = OTG_STATE_UNDEFINED;
1924 	}
1925 	mutex_unlock(&ci->fsm.lock);
1926 }
1927 
1928 /**
1929  * ci_udc_stop: unregister a gadget driver
1930  */
1931 static int ci_udc_stop(struct usb_gadget *gadget)
1932 {
1933 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1934 	unsigned long flags;
1935 
1936 	spin_lock_irqsave(&ci->lock, flags);
1937 	ci->driver = NULL;
1938 
1939 	if (ci->vbus_active) {
1940 		hw_device_state(ci, 0);
1941 		spin_unlock_irqrestore(&ci->lock, flags);
1942 		if (ci->platdata->notify_event)
1943 			ci->platdata->notify_event(ci,
1944 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1945 		_gadget_stop_activity(&ci->gadget);
1946 		spin_lock_irqsave(&ci->lock, flags);
1947 		pm_runtime_put(ci->dev);
1948 	}
1949 
1950 	spin_unlock_irqrestore(&ci->lock, flags);
1951 
1952 	ci_udc_stop_for_otg_fsm(ci);
1953 	return 0;
1954 }
1955 
1956 /******************************************************************************
1957  * BUS block
1958  *****************************************************************************/
1959 /**
1960  * udc_irq: ci interrupt handler
1961  *
1962  * This function returns IRQ_HANDLED if the IRQ has been handled
1963  * It locks access to registers
1964  */
1965 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1966 {
1967 	irqreturn_t retval;
1968 	u32 intr;
1969 
1970 	if (ci == NULL)
1971 		return IRQ_HANDLED;
1972 
1973 	spin_lock(&ci->lock);
1974 
1975 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1976 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1977 				USBMODE_CM_DC) {
1978 			spin_unlock(&ci->lock);
1979 			return IRQ_NONE;
1980 		}
1981 	}
1982 	intr = hw_test_and_clear_intr_active(ci);
1983 
1984 	if (intr) {
1985 		/* order defines priority - do NOT change it */
1986 		if (USBi_URI & intr)
1987 			isr_reset_handler(ci);
1988 
1989 		if (USBi_PCI & intr) {
1990 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1991 				USB_SPEED_HIGH : USB_SPEED_FULL;
1992 			if (ci->suspended) {
1993 				if (ci->driver->resume) {
1994 					spin_unlock(&ci->lock);
1995 					ci->driver->resume(&ci->gadget);
1996 					spin_lock(&ci->lock);
1997 				}
1998 				ci->suspended = 0;
1999 				usb_gadget_set_state(&ci->gadget,
2000 						ci->resume_state);
2001 			}
2002 		}
2003 
2004 		if (USBi_UI  & intr)
2005 			isr_tr_complete_handler(ci);
2006 
2007 		if ((USBi_SLI & intr) && !(ci->suspended)) {
2008 			ci->suspended = 1;
2009 			ci->resume_state = ci->gadget.state;
2010 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
2011 			    ci->driver->suspend) {
2012 				spin_unlock(&ci->lock);
2013 				ci->driver->suspend(&ci->gadget);
2014 				spin_lock(&ci->lock);
2015 			}
2016 			usb_gadget_set_state(&ci->gadget,
2017 					USB_STATE_SUSPENDED);
2018 		}
2019 		retval = IRQ_HANDLED;
2020 	} else {
2021 		retval = IRQ_NONE;
2022 	}
2023 	spin_unlock(&ci->lock);
2024 
2025 	return retval;
2026 }
2027 
2028 /**
2029  * udc_start: initialize gadget role
2030  * @ci: chipidea controller
2031  */
2032 static int udc_start(struct ci_hdrc *ci)
2033 {
2034 	struct device *dev = ci->dev;
2035 	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
2036 	int retval = 0;
2037 
2038 	ci->gadget.ops          = &usb_gadget_ops;
2039 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
2040 	ci->gadget.max_speed    = USB_SPEED_HIGH;
2041 	ci->gadget.name         = ci->platdata->name;
2042 	ci->gadget.otg_caps	= otg_caps;
2043 	ci->gadget.sg_supported = 1;
2044 
2045 	if (ci->platdata->flags & CI_HDRC_REQUIRES_ALIGNED_DMA)
2046 		ci->gadget.quirk_avoids_skb_reserve = 1;
2047 
2048 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
2049 						otg_caps->adp_support))
2050 		ci->gadget.is_otg = 1;
2051 
2052 	INIT_LIST_HEAD(&ci->gadget.ep_list);
2053 
2054 	/* alloc resources */
2055 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev->parent,
2056 				       sizeof(struct ci_hw_qh),
2057 				       64, CI_HDRC_PAGE_SIZE);
2058 	if (ci->qh_pool == NULL)
2059 		return -ENOMEM;
2060 
2061 	ci->td_pool = dma_pool_create("ci_hw_td", dev->parent,
2062 				       sizeof(struct ci_hw_td),
2063 				       64, CI_HDRC_PAGE_SIZE);
2064 	if (ci->td_pool == NULL) {
2065 		retval = -ENOMEM;
2066 		goto free_qh_pool;
2067 	}
2068 
2069 	retval = init_eps(ci);
2070 	if (retval)
2071 		goto free_pools;
2072 
2073 	ci->gadget.ep0 = &ci->ep0in->ep;
2074 
2075 	retval = usb_add_gadget_udc(dev, &ci->gadget);
2076 	if (retval)
2077 		goto destroy_eps;
2078 
2079 	return retval;
2080 
2081 destroy_eps:
2082 	destroy_eps(ci);
2083 free_pools:
2084 	dma_pool_destroy(ci->td_pool);
2085 free_qh_pool:
2086 	dma_pool_destroy(ci->qh_pool);
2087 	return retval;
2088 }
2089 
2090 /**
2091  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
2092  *
2093  * No interrupts active, the IRQ has been released
2094  */
2095 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
2096 {
2097 	if (!ci->roles[CI_ROLE_GADGET])
2098 		return;
2099 
2100 	usb_del_gadget_udc(&ci->gadget);
2101 
2102 	destroy_eps(ci);
2103 
2104 	dma_pool_destroy(ci->td_pool);
2105 	dma_pool_destroy(ci->qh_pool);
2106 }
2107 
2108 static int udc_id_switch_for_device(struct ci_hdrc *ci)
2109 {
2110 	if (ci->platdata->pins_device)
2111 		pinctrl_select_state(ci->platdata->pctl,
2112 				     ci->platdata->pins_device);
2113 
2114 	if (ci->is_otg)
2115 		/* Clear and enable BSV irq */
2116 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
2117 					OTGSC_BSVIS | OTGSC_BSVIE);
2118 
2119 	return 0;
2120 }
2121 
2122 static void udc_id_switch_for_host(struct ci_hdrc *ci)
2123 {
2124 	/*
2125 	 * host doesn't care B_SESSION_VALID event
2126 	 * so clear and disbale BSV irq
2127 	 */
2128 	if (ci->is_otg)
2129 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
2130 
2131 	ci->vbus_active = 0;
2132 
2133 	if (ci->platdata->pins_device && ci->platdata->pins_default)
2134 		pinctrl_select_state(ci->platdata->pctl,
2135 				     ci->platdata->pins_default);
2136 }
2137 
2138 /**
2139  * ci_hdrc_gadget_init - initialize device related bits
2140  * ci: the controller
2141  *
2142  * This function initializes the gadget, if the device is "device capable".
2143  */
2144 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
2145 {
2146 	struct ci_role_driver *rdrv;
2147 	int ret;
2148 
2149 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
2150 		return -ENXIO;
2151 
2152 	rdrv = devm_kzalloc(ci->dev, sizeof(*rdrv), GFP_KERNEL);
2153 	if (!rdrv)
2154 		return -ENOMEM;
2155 
2156 	rdrv->start	= udc_id_switch_for_device;
2157 	rdrv->stop	= udc_id_switch_for_host;
2158 	rdrv->irq	= udc_irq;
2159 	rdrv->name	= "gadget";
2160 
2161 	ret = udc_start(ci);
2162 	if (!ret)
2163 		ci->roles[CI_ROLE_GADGET] = rdrv;
2164 
2165 	return ret;
2166 }
2167