xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision f9834f18)
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 length)
342 {
343 	int i;
344 	u32 temp;
345 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
346 						  GFP_ATOMIC);
347 
348 	if (node == NULL)
349 		return -ENOMEM;
350 
351 	node->ptr = dma_pool_zalloc(hwep->td_pool, GFP_ATOMIC, &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 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
370 	if (length) {
371 		node->ptr->page[0] = cpu_to_le32(temp);
372 		for (i = 1; i < TD_PAGE_COUNT; i++) {
373 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
374 			page &= ~TD_RESERVED_MASK;
375 			node->ptr->page[i] = cpu_to_le32(page);
376 		}
377 	}
378 
379 	hwreq->req.actual += length;
380 
381 	if (!list_empty(&hwreq->tds)) {
382 		/* get the last entry */
383 		lastnode = list_entry(hwreq->tds.prev,
384 				struct td_node, td);
385 		lastnode->ptr->next = cpu_to_le32(node->dma);
386 	}
387 
388 	INIT_LIST_HEAD(&node->td);
389 	list_add_tail(&node->td, &hwreq->tds);
390 
391 	return 0;
392 }
393 
394 /**
395  * _usb_addr: calculates endpoint address from direction & number
396  * @ep:  endpoint
397  */
398 static inline u8 _usb_addr(struct ci_hw_ep *ep)
399 {
400 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
401 }
402 
403 /**
404  * _hardware_enqueue: configures a request at hardware level
405  * @hwep:   endpoint
406  * @hwreq:  request
407  *
408  * This function returns an error code
409  */
410 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
411 {
412 	struct ci_hdrc *ci = hwep->ci;
413 	int ret = 0;
414 	unsigned rest = hwreq->req.length;
415 	int pages = TD_PAGE_COUNT;
416 	struct td_node *firstnode, *lastnode;
417 
418 	/* don't queue twice */
419 	if (hwreq->req.status == -EALREADY)
420 		return -EALREADY;
421 
422 	hwreq->req.status = -EALREADY;
423 
424 	ret = usb_gadget_map_request_by_dev(ci->dev->parent,
425 					    &hwreq->req, hwep->dir);
426 	if (ret)
427 		return ret;
428 
429 	/*
430 	 * The first buffer could be not page aligned.
431 	 * In that case we have to span into one extra td.
432 	 */
433 	if (hwreq->req.dma % PAGE_SIZE)
434 		pages--;
435 
436 	if (rest == 0) {
437 		ret = add_td_to_list(hwep, hwreq, 0);
438 		if (ret < 0)
439 			goto done;
440 	}
441 
442 	while (rest > 0) {
443 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
444 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
445 		ret = add_td_to_list(hwep, hwreq, count);
446 		if (ret < 0)
447 			goto done;
448 
449 		rest -= count;
450 	}
451 
452 	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
453 	    && (hwreq->req.length % hwep->ep.maxpacket == 0)) {
454 		ret = add_td_to_list(hwep, hwreq, 0);
455 		if (ret < 0)
456 			goto done;
457 	}
458 
459 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
460 
461 	lastnode = list_entry(hwreq->tds.prev,
462 		struct td_node, td);
463 
464 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
465 	if (!hwreq->req.no_interrupt)
466 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
467 	wmb();
468 
469 	hwreq->req.actual = 0;
470 	if (!list_empty(&hwep->qh.queue)) {
471 		struct ci_hw_req *hwreqprev;
472 		int n = hw_ep_bit(hwep->num, hwep->dir);
473 		int tmp_stat;
474 		struct td_node *prevlastnode;
475 		u32 next = firstnode->dma & TD_ADDR_MASK;
476 
477 		hwreqprev = list_entry(hwep->qh.queue.prev,
478 				struct ci_hw_req, queue);
479 		prevlastnode = list_entry(hwreqprev->tds.prev,
480 				struct td_node, td);
481 
482 		prevlastnode->ptr->next = cpu_to_le32(next);
483 		wmb();
484 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
485 			goto done;
486 		do {
487 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
488 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
489 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
490 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
491 		if (tmp_stat)
492 			goto done;
493 	}
494 
495 	/*  QH configuration */
496 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
497 	hwep->qh.ptr->td.token &=
498 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
499 
500 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
501 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
502 
503 		if (hwreq->req.length == 0
504 				|| hwreq->req.length % hwep->ep.maxpacket)
505 			mul++;
506 		hwep->qh.ptr->cap |= cpu_to_le32(mul << __ffs(QH_MULT));
507 	}
508 
509 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
510 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
511 done:
512 	return ret;
513 }
514 
515 /*
516  * free_pending_td: remove a pending request for the endpoint
517  * @hwep: endpoint
518  */
519 static void free_pending_td(struct ci_hw_ep *hwep)
520 {
521 	struct td_node *pending = hwep->pending_td;
522 
523 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
524 	hwep->pending_td = NULL;
525 	kfree(pending);
526 }
527 
528 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
529 					   struct td_node *node)
530 {
531 	hwep->qh.ptr->td.next = cpu_to_le32(node->dma);
532 	hwep->qh.ptr->td.token &=
533 		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
534 
535 	return hw_ep_prime(ci, hwep->num, hwep->dir,
536 				hwep->type == USB_ENDPOINT_XFER_CONTROL);
537 }
538 
539 /**
540  * _hardware_dequeue: handles a request at hardware level
541  * @gadget: gadget
542  * @hwep:   endpoint
543  *
544  * This function returns an error code
545  */
546 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
547 {
548 	u32 tmptoken;
549 	struct td_node *node, *tmpnode;
550 	unsigned remaining_length;
551 	unsigned actual = hwreq->req.length;
552 	struct ci_hdrc *ci = hwep->ci;
553 
554 	if (hwreq->req.status != -EALREADY)
555 		return -EINVAL;
556 
557 	hwreq->req.status = 0;
558 
559 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
560 		tmptoken = le32_to_cpu(node->ptr->token);
561 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
562 			int n = hw_ep_bit(hwep->num, hwep->dir);
563 
564 			if (ci->rev == CI_REVISION_24)
565 				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
566 					reprime_dtd(ci, hwep, node);
567 			hwreq->req.status = -EALREADY;
568 			return -EBUSY;
569 		}
570 
571 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
572 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
573 		actual -= remaining_length;
574 
575 		hwreq->req.status = tmptoken & TD_STATUS;
576 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
577 			hwreq->req.status = -EPIPE;
578 			break;
579 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
580 			hwreq->req.status = -EPROTO;
581 			break;
582 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
583 			hwreq->req.status = -EILSEQ;
584 			break;
585 		}
586 
587 		if (remaining_length) {
588 			if (hwep->dir == TX) {
589 				hwreq->req.status = -EPROTO;
590 				break;
591 			}
592 		}
593 		/*
594 		 * As the hardware could still address the freed td
595 		 * which will run the udc unusable, the cleanup of the
596 		 * td has to be delayed by one.
597 		 */
598 		if (hwep->pending_td)
599 			free_pending_td(hwep);
600 
601 		hwep->pending_td = node;
602 		list_del_init(&node->td);
603 	}
604 
605 	usb_gadget_unmap_request_by_dev(hwep->ci->dev->parent,
606 					&hwreq->req, hwep->dir);
607 
608 	hwreq->req.actual += actual;
609 
610 	if (hwreq->req.status)
611 		return hwreq->req.status;
612 
613 	return hwreq->req.actual;
614 }
615 
616 /**
617  * _ep_nuke: dequeues all endpoint requests
618  * @hwep: endpoint
619  *
620  * This function returns an error code
621  * Caller must hold lock
622  */
623 static int _ep_nuke(struct ci_hw_ep *hwep)
624 __releases(hwep->lock)
625 __acquires(hwep->lock)
626 {
627 	struct td_node *node, *tmpnode;
628 	if (hwep == NULL)
629 		return -EINVAL;
630 
631 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
632 
633 	while (!list_empty(&hwep->qh.queue)) {
634 
635 		/* pop oldest request */
636 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
637 						     struct ci_hw_req, queue);
638 
639 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
640 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
641 			list_del_init(&node->td);
642 			node->ptr = NULL;
643 			kfree(node);
644 		}
645 
646 		list_del_init(&hwreq->queue);
647 		hwreq->req.status = -ESHUTDOWN;
648 
649 		if (hwreq->req.complete != NULL) {
650 			spin_unlock(hwep->lock);
651 			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
652 			spin_lock(hwep->lock);
653 		}
654 	}
655 
656 	if (hwep->pending_td)
657 		free_pending_td(hwep);
658 
659 	return 0;
660 }
661 
662 static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
663 {
664 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
665 	int direction, retval = 0;
666 	unsigned long flags;
667 
668 	if (ep == NULL || hwep->ep.desc == NULL)
669 		return -EINVAL;
670 
671 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
672 		return -EOPNOTSUPP;
673 
674 	spin_lock_irqsave(hwep->lock, flags);
675 
676 	if (value && hwep->dir == TX && check_transfer &&
677 		!list_empty(&hwep->qh.queue) &&
678 			!usb_endpoint_xfer_control(hwep->ep.desc)) {
679 		spin_unlock_irqrestore(hwep->lock, flags);
680 		return -EAGAIN;
681 	}
682 
683 	direction = hwep->dir;
684 	do {
685 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
686 
687 		if (!value)
688 			hwep->wedge = 0;
689 
690 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
691 			hwep->dir = (hwep->dir == TX) ? RX : TX;
692 
693 	} while (hwep->dir != direction);
694 
695 	spin_unlock_irqrestore(hwep->lock, flags);
696 	return retval;
697 }
698 
699 
700 /**
701  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
702  * @gadget: gadget
703  *
704  * This function returns an error code
705  */
706 static int _gadget_stop_activity(struct usb_gadget *gadget)
707 {
708 	struct usb_ep *ep;
709 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
710 	unsigned long flags;
711 
712 	/* flush all endpoints */
713 	gadget_for_each_ep(ep, gadget) {
714 		usb_ep_fifo_flush(ep);
715 	}
716 	usb_ep_fifo_flush(&ci->ep0out->ep);
717 	usb_ep_fifo_flush(&ci->ep0in->ep);
718 
719 	/* make sure to disable all endpoints */
720 	gadget_for_each_ep(ep, gadget) {
721 		usb_ep_disable(ep);
722 	}
723 
724 	if (ci->status != NULL) {
725 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
726 		ci->status = NULL;
727 	}
728 
729 	spin_lock_irqsave(&ci->lock, flags);
730 	ci->gadget.speed = USB_SPEED_UNKNOWN;
731 	ci->remote_wakeup = 0;
732 	ci->suspended = 0;
733 	spin_unlock_irqrestore(&ci->lock, flags);
734 
735 	return 0;
736 }
737 
738 /******************************************************************************
739  * ISR block
740  *****************************************************************************/
741 /**
742  * isr_reset_handler: USB reset interrupt handler
743  * @ci: UDC device
744  *
745  * This function resets USB engine after a bus reset occurred
746  */
747 static void isr_reset_handler(struct ci_hdrc *ci)
748 __releases(ci->lock)
749 __acquires(ci->lock)
750 {
751 	int retval;
752 
753 	spin_unlock(&ci->lock);
754 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
755 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
756 
757 	retval = _gadget_stop_activity(&ci->gadget);
758 	if (retval)
759 		goto done;
760 
761 	retval = hw_usb_reset(ci);
762 	if (retval)
763 		goto done;
764 
765 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
766 	if (ci->status == NULL)
767 		retval = -ENOMEM;
768 
769 done:
770 	spin_lock(&ci->lock);
771 
772 	if (retval)
773 		dev_err(ci->dev, "error: %i\n", retval);
774 }
775 
776 /**
777  * isr_get_status_complete: get_status request complete function
778  * @ep:  endpoint
779  * @req: request handled
780  *
781  * Caller must release lock
782  */
783 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
784 {
785 	if (ep == NULL || req == NULL)
786 		return;
787 
788 	kfree(req->buf);
789 	usb_ep_free_request(ep, req);
790 }
791 
792 /**
793  * _ep_queue: queues (submits) an I/O request to an endpoint
794  * @ep:        endpoint
795  * @req:       request
796  * @gfp_flags: GFP flags (not used)
797  *
798  * Caller must hold lock
799  * This function returns an error code
800  */
801 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
802 		    gfp_t __maybe_unused gfp_flags)
803 {
804 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
805 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
806 	struct ci_hdrc *ci = hwep->ci;
807 	int retval = 0;
808 
809 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
810 		return -EINVAL;
811 
812 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
813 		if (req->length)
814 			hwep = (ci->ep0_dir == RX) ?
815 			       ci->ep0out : ci->ep0in;
816 		if (!list_empty(&hwep->qh.queue)) {
817 			_ep_nuke(hwep);
818 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
819 				 _usb_addr(hwep));
820 		}
821 	}
822 
823 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
824 	    hwreq->req.length > hwep->ep.mult * hwep->ep.maxpacket) {
825 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
826 		return -EMSGSIZE;
827 	}
828 
829 	/* first nuke then test link, e.g. previous status has not sent */
830 	if (!list_empty(&hwreq->queue)) {
831 		dev_err(hwep->ci->dev, "request already in queue\n");
832 		return -EBUSY;
833 	}
834 
835 	/* push request */
836 	hwreq->req.status = -EINPROGRESS;
837 	hwreq->req.actual = 0;
838 
839 	retval = _hardware_enqueue(hwep, hwreq);
840 
841 	if (retval == -EALREADY)
842 		retval = 0;
843 	if (!retval)
844 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
845 
846 	return retval;
847 }
848 
849 /**
850  * isr_get_status_response: get_status request response
851  * @ci: ci struct
852  * @setup: setup request packet
853  *
854  * This function returns an error code
855  */
856 static int isr_get_status_response(struct ci_hdrc *ci,
857 				   struct usb_ctrlrequest *setup)
858 __releases(hwep->lock)
859 __acquires(hwep->lock)
860 {
861 	struct ci_hw_ep *hwep = ci->ep0in;
862 	struct usb_request *req = NULL;
863 	gfp_t gfp_flags = GFP_ATOMIC;
864 	int dir, num, retval;
865 
866 	if (hwep == NULL || setup == NULL)
867 		return -EINVAL;
868 
869 	spin_unlock(hwep->lock);
870 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
871 	spin_lock(hwep->lock);
872 	if (req == NULL)
873 		return -ENOMEM;
874 
875 	req->complete = isr_get_status_complete;
876 	req->length   = 2;
877 	req->buf      = kzalloc(req->length, gfp_flags);
878 	if (req->buf == NULL) {
879 		retval = -ENOMEM;
880 		goto err_free_req;
881 	}
882 
883 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
884 		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
885 			ci->gadget.is_selfpowered;
886 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
887 		   == USB_RECIP_ENDPOINT) {
888 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
889 			TX : RX;
890 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
891 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
892 	}
893 	/* else do nothing; reserved for future use */
894 
895 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
896 	if (retval)
897 		goto err_free_buf;
898 
899 	return 0;
900 
901  err_free_buf:
902 	kfree(req->buf);
903  err_free_req:
904 	spin_unlock(hwep->lock);
905 	usb_ep_free_request(&hwep->ep, req);
906 	spin_lock(hwep->lock);
907 	return retval;
908 }
909 
910 /**
911  * isr_setup_status_complete: setup_status request complete function
912  * @ep:  endpoint
913  * @req: request handled
914  *
915  * Caller must release lock. Put the port in test mode if test mode
916  * feature is selected.
917  */
918 static void
919 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
920 {
921 	struct ci_hdrc *ci = req->context;
922 	unsigned long flags;
923 
924 	if (ci->setaddr) {
925 		hw_usb_set_address(ci, ci->address);
926 		ci->setaddr = false;
927 		if (ci->address)
928 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
929 	}
930 
931 	spin_lock_irqsave(&ci->lock, flags);
932 	if (ci->test_mode)
933 		hw_port_test_set(ci, ci->test_mode);
934 	spin_unlock_irqrestore(&ci->lock, flags);
935 }
936 
937 /**
938  * isr_setup_status_phase: queues the status phase of a setup transation
939  * @ci: ci struct
940  *
941  * This function returns an error code
942  */
943 static int isr_setup_status_phase(struct ci_hdrc *ci)
944 {
945 	struct ci_hw_ep *hwep;
946 
947 	/*
948 	 * Unexpected USB controller behavior, caused by bad signal integrity
949 	 * or ground reference problems, can lead to isr_setup_status_phase
950 	 * being called with ci->status equal to NULL.
951 	 * If this situation occurs, you should review your USB hardware design.
952 	 */
953 	if (WARN_ON_ONCE(!ci->status))
954 		return -EPIPE;
955 
956 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
957 	ci->status->context = ci;
958 	ci->status->complete = isr_setup_status_complete;
959 
960 	return _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
961 }
962 
963 /**
964  * isr_tr_complete_low: transaction complete low level handler
965  * @hwep: endpoint
966  *
967  * This function returns an error code
968  * Caller must hold lock
969  */
970 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
971 __releases(hwep->lock)
972 __acquires(hwep->lock)
973 {
974 	struct ci_hw_req *hwreq, *hwreqtemp;
975 	struct ci_hw_ep *hweptemp = hwep;
976 	int retval = 0;
977 
978 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
979 			queue) {
980 		retval = _hardware_dequeue(hwep, hwreq);
981 		if (retval < 0)
982 			break;
983 		list_del_init(&hwreq->queue);
984 		if (hwreq->req.complete != NULL) {
985 			spin_unlock(hwep->lock);
986 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
987 					hwreq->req.length)
988 				hweptemp = hwep->ci->ep0in;
989 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
990 			spin_lock(hwep->lock);
991 		}
992 	}
993 
994 	if (retval == -EBUSY)
995 		retval = 0;
996 
997 	return retval;
998 }
999 
1000 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
1001 {
1002 	dev_warn(&ci->gadget.dev,
1003 		"connect the device to an alternate port if you want HNP\n");
1004 	return isr_setup_status_phase(ci);
1005 }
1006 
1007 /**
1008  * isr_setup_packet_handler: setup packet handler
1009  * @ci: UDC descriptor
1010  *
1011  * This function handles setup packet
1012  */
1013 static void isr_setup_packet_handler(struct ci_hdrc *ci)
1014 __releases(ci->lock)
1015 __acquires(ci->lock)
1016 {
1017 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1018 	struct usb_ctrlrequest req;
1019 	int type, num, dir, err = -EINVAL;
1020 	u8 tmode = 0;
1021 
1022 	/*
1023 	 * Flush data and handshake transactions of previous
1024 	 * setup packet.
1025 	 */
1026 	_ep_nuke(ci->ep0out);
1027 	_ep_nuke(ci->ep0in);
1028 
1029 	/* read_setup_packet */
1030 	do {
1031 		hw_test_and_set_setup_guard(ci);
1032 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1033 	} while (!hw_test_and_clear_setup_guard(ci));
1034 
1035 	type = req.bRequestType;
1036 
1037 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1038 
1039 	switch (req.bRequest) {
1040 	case USB_REQ_CLEAR_FEATURE:
1041 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1042 				le16_to_cpu(req.wValue) ==
1043 				USB_ENDPOINT_HALT) {
1044 			if (req.wLength != 0)
1045 				break;
1046 			num  = le16_to_cpu(req.wIndex);
1047 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1048 			num &= USB_ENDPOINT_NUMBER_MASK;
1049 			if (dir == TX)
1050 				num += ci->hw_ep_max / 2;
1051 			if (!ci->ci_hw_ep[num].wedge) {
1052 				spin_unlock(&ci->lock);
1053 				err = usb_ep_clear_halt(
1054 					&ci->ci_hw_ep[num].ep);
1055 				spin_lock(&ci->lock);
1056 				if (err)
1057 					break;
1058 			}
1059 			err = isr_setup_status_phase(ci);
1060 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1061 				le16_to_cpu(req.wValue) ==
1062 				USB_DEVICE_REMOTE_WAKEUP) {
1063 			if (req.wLength != 0)
1064 				break;
1065 			ci->remote_wakeup = 0;
1066 			err = isr_setup_status_phase(ci);
1067 		} else {
1068 			goto delegate;
1069 		}
1070 		break;
1071 	case USB_REQ_GET_STATUS:
1072 		if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
1073 			le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
1074 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1075 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1076 			goto delegate;
1077 		if (le16_to_cpu(req.wLength) != 2 ||
1078 		    le16_to_cpu(req.wValue)  != 0)
1079 			break;
1080 		err = isr_get_status_response(ci, &req);
1081 		break;
1082 	case USB_REQ_SET_ADDRESS:
1083 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1084 			goto delegate;
1085 		if (le16_to_cpu(req.wLength) != 0 ||
1086 		    le16_to_cpu(req.wIndex)  != 0)
1087 			break;
1088 		ci->address = (u8)le16_to_cpu(req.wValue);
1089 		ci->setaddr = true;
1090 		err = isr_setup_status_phase(ci);
1091 		break;
1092 	case USB_REQ_SET_FEATURE:
1093 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1094 				le16_to_cpu(req.wValue) ==
1095 				USB_ENDPOINT_HALT) {
1096 			if (req.wLength != 0)
1097 				break;
1098 			num  = le16_to_cpu(req.wIndex);
1099 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1100 			num &= USB_ENDPOINT_NUMBER_MASK;
1101 			if (dir == TX)
1102 				num += ci->hw_ep_max / 2;
1103 
1104 			spin_unlock(&ci->lock);
1105 			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1106 			spin_lock(&ci->lock);
1107 			if (!err)
1108 				isr_setup_status_phase(ci);
1109 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1110 			if (req.wLength != 0)
1111 				break;
1112 			switch (le16_to_cpu(req.wValue)) {
1113 			case USB_DEVICE_REMOTE_WAKEUP:
1114 				ci->remote_wakeup = 1;
1115 				err = isr_setup_status_phase(ci);
1116 				break;
1117 			case USB_DEVICE_TEST_MODE:
1118 				tmode = le16_to_cpu(req.wIndex) >> 8;
1119 				switch (tmode) {
1120 				case TEST_J:
1121 				case TEST_K:
1122 				case TEST_SE0_NAK:
1123 				case TEST_PACKET:
1124 				case TEST_FORCE_EN:
1125 					ci->test_mode = tmode;
1126 					err = isr_setup_status_phase(
1127 							ci);
1128 					break;
1129 				default:
1130 					break;
1131 				}
1132 				break;
1133 			case USB_DEVICE_B_HNP_ENABLE:
1134 				if (ci_otg_is_fsm_mode(ci)) {
1135 					ci->gadget.b_hnp_enable = 1;
1136 					err = isr_setup_status_phase(
1137 							ci);
1138 				}
1139 				break;
1140 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1141 				if (ci_otg_is_fsm_mode(ci))
1142 					err = otg_a_alt_hnp_support(ci);
1143 				break;
1144 			case USB_DEVICE_A_HNP_SUPPORT:
1145 				if (ci_otg_is_fsm_mode(ci)) {
1146 					ci->gadget.a_hnp_support = 1;
1147 					err = isr_setup_status_phase(
1148 							ci);
1149 				}
1150 				break;
1151 			default:
1152 				goto delegate;
1153 			}
1154 		} else {
1155 			goto delegate;
1156 		}
1157 		break;
1158 	default:
1159 delegate:
1160 		if (req.wLength == 0)   /* no data phase */
1161 			ci->ep0_dir = TX;
1162 
1163 		spin_unlock(&ci->lock);
1164 		err = ci->driver->setup(&ci->gadget, &req);
1165 		spin_lock(&ci->lock);
1166 		break;
1167 	}
1168 
1169 	if (err < 0) {
1170 		spin_unlock(&ci->lock);
1171 		if (_ep_set_halt(&hwep->ep, 1, false))
1172 			dev_err(ci->dev, "error: _ep_set_halt\n");
1173 		spin_lock(&ci->lock);
1174 	}
1175 }
1176 
1177 /**
1178  * isr_tr_complete_handler: transaction complete interrupt handler
1179  * @ci: UDC descriptor
1180  *
1181  * This function handles traffic events
1182  */
1183 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1184 __releases(ci->lock)
1185 __acquires(ci->lock)
1186 {
1187 	unsigned i;
1188 	int err;
1189 
1190 	for (i = 0; i < ci->hw_ep_max; i++) {
1191 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1192 
1193 		if (hwep->ep.desc == NULL)
1194 			continue;   /* not configured */
1195 
1196 		if (hw_test_and_clear_complete(ci, i)) {
1197 			err = isr_tr_complete_low(hwep);
1198 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1199 				if (err > 0)   /* needs status phase */
1200 					err = isr_setup_status_phase(ci);
1201 				if (err < 0) {
1202 					spin_unlock(&ci->lock);
1203 					if (_ep_set_halt(&hwep->ep, 1, false))
1204 						dev_err(ci->dev,
1205 						"error: _ep_set_halt\n");
1206 					spin_lock(&ci->lock);
1207 				}
1208 			}
1209 		}
1210 
1211 		/* Only handle setup packet below */
1212 		if (i == 0 &&
1213 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1214 			isr_setup_packet_handler(ci);
1215 	}
1216 }
1217 
1218 /******************************************************************************
1219  * ENDPT block
1220  *****************************************************************************/
1221 /**
1222  * ep_enable: configure endpoint, making it usable
1223  *
1224  * Check usb_ep_enable() at "usb_gadget.h" for details
1225  */
1226 static int ep_enable(struct usb_ep *ep,
1227 		     const struct usb_endpoint_descriptor *desc)
1228 {
1229 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1230 	int retval = 0;
1231 	unsigned long flags;
1232 	u32 cap = 0;
1233 
1234 	if (ep == NULL || desc == NULL)
1235 		return -EINVAL;
1236 
1237 	spin_lock_irqsave(hwep->lock, flags);
1238 
1239 	/* only internal SW should enable ctrl endpts */
1240 
1241 	if (!list_empty(&hwep->qh.queue)) {
1242 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1243 		spin_unlock_irqrestore(hwep->lock, flags);
1244 		return -EBUSY;
1245 	}
1246 
1247 	hwep->ep.desc = desc;
1248 
1249 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1250 	hwep->num  = usb_endpoint_num(desc);
1251 	hwep->type = usb_endpoint_type(desc);
1252 
1253 	hwep->ep.maxpacket = usb_endpoint_maxp(desc);
1254 	hwep->ep.mult = usb_endpoint_maxp_mult(desc);
1255 
1256 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1257 		cap |= QH_IOS;
1258 
1259 	cap |= QH_ZLT;
1260 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1261 	/*
1262 	 * For ISO-TX, we set mult at QH as the largest value, and use
1263 	 * MultO at TD as real mult value.
1264 	 */
1265 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1266 		cap |= 3 << __ffs(QH_MULT);
1267 
1268 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1269 
1270 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1271 
1272 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1273 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1274 		retval = -EINVAL;
1275 	}
1276 
1277 	/*
1278 	 * Enable endpoints in the HW other than ep0 as ep0
1279 	 * is always enabled
1280 	 */
1281 	if (hwep->num)
1282 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1283 				       hwep->type);
1284 
1285 	spin_unlock_irqrestore(hwep->lock, flags);
1286 	return retval;
1287 }
1288 
1289 /**
1290  * ep_disable: endpoint is no longer usable
1291  *
1292  * Check usb_ep_disable() at "usb_gadget.h" for details
1293  */
1294 static int ep_disable(struct usb_ep *ep)
1295 {
1296 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1297 	int direction, retval = 0;
1298 	unsigned long flags;
1299 
1300 	if (ep == NULL)
1301 		return -EINVAL;
1302 	else if (hwep->ep.desc == NULL)
1303 		return -EBUSY;
1304 
1305 	spin_lock_irqsave(hwep->lock, flags);
1306 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1307 		spin_unlock_irqrestore(hwep->lock, flags);
1308 		return 0;
1309 	}
1310 
1311 	/* only internal SW should disable ctrl endpts */
1312 
1313 	direction = hwep->dir;
1314 	do {
1315 		retval |= _ep_nuke(hwep);
1316 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1317 
1318 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1319 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1320 
1321 	} while (hwep->dir != direction);
1322 
1323 	hwep->ep.desc = NULL;
1324 
1325 	spin_unlock_irqrestore(hwep->lock, flags);
1326 	return retval;
1327 }
1328 
1329 /**
1330  * ep_alloc_request: allocate a request object to use with this endpoint
1331  *
1332  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1333  */
1334 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1335 {
1336 	struct ci_hw_req *hwreq = NULL;
1337 
1338 	if (ep == NULL)
1339 		return NULL;
1340 
1341 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1342 	if (hwreq != NULL) {
1343 		INIT_LIST_HEAD(&hwreq->queue);
1344 		INIT_LIST_HEAD(&hwreq->tds);
1345 	}
1346 
1347 	return (hwreq == NULL) ? NULL : &hwreq->req;
1348 }
1349 
1350 /**
1351  * ep_free_request: frees a request object
1352  *
1353  * Check usb_ep_free_request() at "usb_gadget.h" for details
1354  */
1355 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1356 {
1357 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1358 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1359 	struct td_node *node, *tmpnode;
1360 	unsigned long flags;
1361 
1362 	if (ep == NULL || req == NULL) {
1363 		return;
1364 	} else if (!list_empty(&hwreq->queue)) {
1365 		dev_err(hwep->ci->dev, "freeing queued request\n");
1366 		return;
1367 	}
1368 
1369 	spin_lock_irqsave(hwep->lock, flags);
1370 
1371 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1372 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1373 		list_del_init(&node->td);
1374 		node->ptr = NULL;
1375 		kfree(node);
1376 	}
1377 
1378 	kfree(hwreq);
1379 
1380 	spin_unlock_irqrestore(hwep->lock, flags);
1381 }
1382 
1383 /**
1384  * ep_queue: queues (submits) an I/O request to an endpoint
1385  *
1386  * Check usb_ep_queue()* at usb_gadget.h" for details
1387  */
1388 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1389 		    gfp_t __maybe_unused gfp_flags)
1390 {
1391 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1392 	int retval = 0;
1393 	unsigned long flags;
1394 
1395 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1396 		return -EINVAL;
1397 
1398 	spin_lock_irqsave(hwep->lock, flags);
1399 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1400 		spin_unlock_irqrestore(hwep->lock, flags);
1401 		return 0;
1402 	}
1403 	retval = _ep_queue(ep, req, gfp_flags);
1404 	spin_unlock_irqrestore(hwep->lock, flags);
1405 	return retval;
1406 }
1407 
1408 /**
1409  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1410  *
1411  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1412  */
1413 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1414 {
1415 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1416 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1417 	unsigned long flags;
1418 	struct td_node *node, *tmpnode;
1419 
1420 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1421 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1422 		list_empty(&hwep->qh.queue))
1423 		return -EINVAL;
1424 
1425 	spin_lock_irqsave(hwep->lock, flags);
1426 	if (hwep->ci->gadget.speed != USB_SPEED_UNKNOWN)
1427 		hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1428 
1429 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1430 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1431 		list_del(&node->td);
1432 		kfree(node);
1433 	}
1434 
1435 	/* pop request */
1436 	list_del_init(&hwreq->queue);
1437 
1438 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1439 
1440 	req->status = -ECONNRESET;
1441 
1442 	if (hwreq->req.complete != NULL) {
1443 		spin_unlock(hwep->lock);
1444 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1445 		spin_lock(hwep->lock);
1446 	}
1447 
1448 	spin_unlock_irqrestore(hwep->lock, flags);
1449 	return 0;
1450 }
1451 
1452 /**
1453  * ep_set_halt: sets the endpoint halt feature
1454  *
1455  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1456  */
1457 static int ep_set_halt(struct usb_ep *ep, int value)
1458 {
1459 	return _ep_set_halt(ep, value, true);
1460 }
1461 
1462 /**
1463  * ep_set_wedge: sets the halt feature and ignores clear requests
1464  *
1465  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1466  */
1467 static int ep_set_wedge(struct usb_ep *ep)
1468 {
1469 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1470 	unsigned long flags;
1471 
1472 	if (ep == NULL || hwep->ep.desc == NULL)
1473 		return -EINVAL;
1474 
1475 	spin_lock_irqsave(hwep->lock, flags);
1476 	hwep->wedge = 1;
1477 	spin_unlock_irqrestore(hwep->lock, flags);
1478 
1479 	return usb_ep_set_halt(ep);
1480 }
1481 
1482 /**
1483  * ep_fifo_flush: flushes contents of a fifo
1484  *
1485  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1486  */
1487 static void ep_fifo_flush(struct usb_ep *ep)
1488 {
1489 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1490 	unsigned long flags;
1491 
1492 	if (ep == NULL) {
1493 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1494 		return;
1495 	}
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;
1501 	}
1502 
1503 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1504 
1505 	spin_unlock_irqrestore(hwep->lock, flags);
1506 }
1507 
1508 /**
1509  * Endpoint-specific part of the API to the USB controller hardware
1510  * Check "usb_gadget.h" for details
1511  */
1512 static const struct usb_ep_ops usb_ep_ops = {
1513 	.enable	       = ep_enable,
1514 	.disable       = ep_disable,
1515 	.alloc_request = ep_alloc_request,
1516 	.free_request  = ep_free_request,
1517 	.queue	       = ep_queue,
1518 	.dequeue       = ep_dequeue,
1519 	.set_halt      = ep_set_halt,
1520 	.set_wedge     = ep_set_wedge,
1521 	.fifo_flush    = ep_fifo_flush,
1522 };
1523 
1524 /******************************************************************************
1525  * GADGET block
1526  *****************************************************************************/
1527 /**
1528  * ci_hdrc_gadget_connect: caller makes sure gadget driver is binded
1529  */
1530 static void ci_hdrc_gadget_connect(struct usb_gadget *_gadget, int is_active)
1531 {
1532 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1533 	unsigned long flags;
1534 
1535 	if (is_active) {
1536 		pm_runtime_get_sync(&_gadget->dev);
1537 		hw_device_reset(ci);
1538 		spin_lock_irqsave(&ci->lock, flags);
1539 		if (ci->driver) {
1540 			hw_device_state(ci, ci->ep0out->qh.dma);
1541 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1542 			usb_udc_vbus_handler(_gadget, true);
1543 		}
1544 		spin_unlock_irqrestore(&ci->lock, flags);
1545 	} else {
1546 		usb_udc_vbus_handler(_gadget, false);
1547 		if (ci->driver)
1548 			ci->driver->disconnect(&ci->gadget);
1549 		hw_device_state(ci, 0);
1550 		if (ci->platdata->notify_event)
1551 			ci->platdata->notify_event(ci,
1552 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1553 		_gadget_stop_activity(&ci->gadget);
1554 		pm_runtime_put_sync(&_gadget->dev);
1555 		usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1556 	}
1557 }
1558 
1559 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1560 {
1561 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1562 	unsigned long flags;
1563 
1564 	spin_lock_irqsave(&ci->lock, flags);
1565 	ci->vbus_active = is_active;
1566 	spin_unlock_irqrestore(&ci->lock, flags);
1567 
1568 	if (ci->usb_phy)
1569 		usb_phy_set_charger_state(ci->usb_phy, is_active ?
1570 			USB_CHARGER_PRESENT : USB_CHARGER_ABSENT);
1571 
1572 	if (ci->driver)
1573 		ci_hdrc_gadget_connect(_gadget, is_active);
1574 
1575 	return 0;
1576 }
1577 
1578 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1579 {
1580 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1581 	unsigned long flags;
1582 	int ret = 0;
1583 
1584 	spin_lock_irqsave(&ci->lock, flags);
1585 	if (ci->gadget.speed == USB_SPEED_UNKNOWN) {
1586 		spin_unlock_irqrestore(&ci->lock, flags);
1587 		return 0;
1588 	}
1589 	if (!ci->remote_wakeup) {
1590 		ret = -EOPNOTSUPP;
1591 		goto out;
1592 	}
1593 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1594 		ret = -EINVAL;
1595 		goto out;
1596 	}
1597 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1598 out:
1599 	spin_unlock_irqrestore(&ci->lock, flags);
1600 	return ret;
1601 }
1602 
1603 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1604 {
1605 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1606 
1607 	if (ci->usb_phy)
1608 		return usb_phy_set_power(ci->usb_phy, ma);
1609 	return -ENOTSUPP;
1610 }
1611 
1612 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1613 {
1614 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1615 	struct ci_hw_ep *hwep = ci->ep0in;
1616 	unsigned long flags;
1617 
1618 	spin_lock_irqsave(hwep->lock, flags);
1619 	_gadget->is_selfpowered = (is_on != 0);
1620 	spin_unlock_irqrestore(hwep->lock, flags);
1621 
1622 	return 0;
1623 }
1624 
1625 /* Change Data+ pullup status
1626  * this func is used by usb_gadget_connect/disconnect
1627  */
1628 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1629 {
1630 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1631 
1632 	/*
1633 	 * Data+ pullup controlled by OTG state machine in OTG fsm mode;
1634 	 * and don't touch Data+ in host mode for dual role config.
1635 	 */
1636 	if (ci_otg_is_fsm_mode(ci) || ci->role == CI_ROLE_HOST)
1637 		return 0;
1638 
1639 	pm_runtime_get_sync(&ci->gadget.dev);
1640 	if (is_on)
1641 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1642 	else
1643 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1644 	pm_runtime_put_sync(&ci->gadget.dev);
1645 
1646 	return 0;
1647 }
1648 
1649 static int ci_udc_start(struct usb_gadget *gadget,
1650 			 struct usb_gadget_driver *driver);
1651 static int ci_udc_stop(struct usb_gadget *gadget);
1652 
1653 /* Match ISOC IN from the highest endpoint */
1654 static struct usb_ep *ci_udc_match_ep(struct usb_gadget *gadget,
1655 			      struct usb_endpoint_descriptor *desc,
1656 			      struct usb_ss_ep_comp_descriptor *comp_desc)
1657 {
1658 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1659 	struct usb_ep *ep;
1660 
1661 	if (usb_endpoint_xfer_isoc(desc) && usb_endpoint_dir_in(desc)) {
1662 		list_for_each_entry_reverse(ep, &ci->gadget.ep_list, ep_list) {
1663 			if (ep->caps.dir_in && !ep->claimed)
1664 				return ep;
1665 		}
1666 	}
1667 
1668 	return NULL;
1669 }
1670 
1671 /**
1672  * Device operations part of the API to the USB controller hardware,
1673  * which don't involve endpoints (or i/o)
1674  * Check  "usb_gadget.h" for details
1675  */
1676 static const struct usb_gadget_ops usb_gadget_ops = {
1677 	.vbus_session	= ci_udc_vbus_session,
1678 	.wakeup		= ci_udc_wakeup,
1679 	.set_selfpowered	= ci_udc_selfpowered,
1680 	.pullup		= ci_udc_pullup,
1681 	.vbus_draw	= ci_udc_vbus_draw,
1682 	.udc_start	= ci_udc_start,
1683 	.udc_stop	= ci_udc_stop,
1684 	.match_ep 	= ci_udc_match_ep,
1685 };
1686 
1687 static int init_eps(struct ci_hdrc *ci)
1688 {
1689 	int retval = 0, i, j;
1690 
1691 	for (i = 0; i < ci->hw_ep_max/2; i++)
1692 		for (j = RX; j <= TX; j++) {
1693 			int k = i + j * ci->hw_ep_max/2;
1694 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1695 
1696 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1697 					(j == TX)  ? "in" : "out");
1698 
1699 			hwep->ci          = ci;
1700 			hwep->lock         = &ci->lock;
1701 			hwep->td_pool      = ci->td_pool;
1702 
1703 			hwep->ep.name      = hwep->name;
1704 			hwep->ep.ops       = &usb_ep_ops;
1705 
1706 			if (i == 0) {
1707 				hwep->ep.caps.type_control = true;
1708 			} else {
1709 				hwep->ep.caps.type_iso = true;
1710 				hwep->ep.caps.type_bulk = true;
1711 				hwep->ep.caps.type_int = true;
1712 			}
1713 
1714 			if (j == TX)
1715 				hwep->ep.caps.dir_in = true;
1716 			else
1717 				hwep->ep.caps.dir_out = true;
1718 
1719 			/*
1720 			 * for ep0: maxP defined in desc, for other
1721 			 * eps, maxP is set by epautoconfig() called
1722 			 * by gadget layer
1723 			 */
1724 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1725 
1726 			INIT_LIST_HEAD(&hwep->qh.queue);
1727 			hwep->qh.ptr = dma_pool_zalloc(ci->qh_pool, GFP_KERNEL,
1728 						       &hwep->qh.dma);
1729 			if (hwep->qh.ptr == NULL)
1730 				retval = -ENOMEM;
1731 
1732 			/*
1733 			 * set up shorthands for ep0 out and in endpoints,
1734 			 * don't add to gadget's ep_list
1735 			 */
1736 			if (i == 0) {
1737 				if (j == RX)
1738 					ci->ep0out = hwep;
1739 				else
1740 					ci->ep0in = hwep;
1741 
1742 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1743 				continue;
1744 			}
1745 
1746 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1747 		}
1748 
1749 	return retval;
1750 }
1751 
1752 static void destroy_eps(struct ci_hdrc *ci)
1753 {
1754 	int i;
1755 
1756 	for (i = 0; i < ci->hw_ep_max; i++) {
1757 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1758 
1759 		if (hwep->pending_td)
1760 			free_pending_td(hwep);
1761 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1762 	}
1763 }
1764 
1765 /**
1766  * ci_udc_start: register a gadget driver
1767  * @gadget: our gadget
1768  * @driver: the driver being registered
1769  *
1770  * Interrupts are enabled here.
1771  */
1772 static int ci_udc_start(struct usb_gadget *gadget,
1773 			 struct usb_gadget_driver *driver)
1774 {
1775 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1776 	int retval;
1777 
1778 	if (driver->disconnect == NULL)
1779 		return -EINVAL;
1780 
1781 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1782 	retval = usb_ep_enable(&ci->ep0out->ep);
1783 	if (retval)
1784 		return retval;
1785 
1786 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1787 	retval = usb_ep_enable(&ci->ep0in->ep);
1788 	if (retval)
1789 		return retval;
1790 
1791 	ci->driver = driver;
1792 
1793 	/* Start otg fsm for B-device */
1794 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1795 		ci_hdrc_otg_fsm_start(ci);
1796 		return retval;
1797 	}
1798 
1799 	if (ci->vbus_active)
1800 		ci_hdrc_gadget_connect(gadget, 1);
1801 	else
1802 		usb_udc_vbus_handler(&ci->gadget, false);
1803 
1804 	return retval;
1805 }
1806 
1807 static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
1808 {
1809 	if (!ci_otg_is_fsm_mode(ci))
1810 		return;
1811 
1812 	mutex_lock(&ci->fsm.lock);
1813 	if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
1814 		ci->fsm.a_bidl_adis_tmout = 1;
1815 		ci_hdrc_otg_fsm_start(ci);
1816 	} else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
1817 		ci->fsm.protocol = PROTO_UNDEF;
1818 		ci->fsm.otg->state = OTG_STATE_UNDEFINED;
1819 	}
1820 	mutex_unlock(&ci->fsm.lock);
1821 }
1822 
1823 /**
1824  * ci_udc_stop: unregister a gadget driver
1825  */
1826 static int ci_udc_stop(struct usb_gadget *gadget)
1827 {
1828 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1829 	unsigned long flags;
1830 
1831 	spin_lock_irqsave(&ci->lock, flags);
1832 	ci->driver = NULL;
1833 
1834 	if (ci->vbus_active) {
1835 		hw_device_state(ci, 0);
1836 		spin_unlock_irqrestore(&ci->lock, flags);
1837 		if (ci->platdata->notify_event)
1838 			ci->platdata->notify_event(ci,
1839 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1840 		_gadget_stop_activity(&ci->gadget);
1841 		spin_lock_irqsave(&ci->lock, flags);
1842 		pm_runtime_put(&ci->gadget.dev);
1843 	}
1844 
1845 	spin_unlock_irqrestore(&ci->lock, flags);
1846 
1847 	ci_udc_stop_for_otg_fsm(ci);
1848 	return 0;
1849 }
1850 
1851 /******************************************************************************
1852  * BUS block
1853  *****************************************************************************/
1854 /**
1855  * udc_irq: ci interrupt handler
1856  *
1857  * This function returns IRQ_HANDLED if the IRQ has been handled
1858  * It locks access to registers
1859  */
1860 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1861 {
1862 	irqreturn_t retval;
1863 	u32 intr;
1864 
1865 	if (ci == NULL)
1866 		return IRQ_HANDLED;
1867 
1868 	spin_lock(&ci->lock);
1869 
1870 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1871 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1872 				USBMODE_CM_DC) {
1873 			spin_unlock(&ci->lock);
1874 			return IRQ_NONE;
1875 		}
1876 	}
1877 	intr = hw_test_and_clear_intr_active(ci);
1878 
1879 	if (intr) {
1880 		/* order defines priority - do NOT change it */
1881 		if (USBi_URI & intr)
1882 			isr_reset_handler(ci);
1883 
1884 		if (USBi_PCI & intr) {
1885 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1886 				USB_SPEED_HIGH : USB_SPEED_FULL;
1887 			if (ci->suspended) {
1888 				if (ci->driver->resume) {
1889 					spin_unlock(&ci->lock);
1890 					ci->driver->resume(&ci->gadget);
1891 					spin_lock(&ci->lock);
1892 				}
1893 				ci->suspended = 0;
1894 				usb_gadget_set_state(&ci->gadget,
1895 						ci->resume_state);
1896 			}
1897 		}
1898 
1899 		if (USBi_UI  & intr)
1900 			isr_tr_complete_handler(ci);
1901 
1902 		if ((USBi_SLI & intr) && !(ci->suspended)) {
1903 			ci->suspended = 1;
1904 			ci->resume_state = ci->gadget.state;
1905 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1906 			    ci->driver->suspend) {
1907 				spin_unlock(&ci->lock);
1908 				ci->driver->suspend(&ci->gadget);
1909 				spin_lock(&ci->lock);
1910 			}
1911 			usb_gadget_set_state(&ci->gadget,
1912 					USB_STATE_SUSPENDED);
1913 		}
1914 		retval = IRQ_HANDLED;
1915 	} else {
1916 		retval = IRQ_NONE;
1917 	}
1918 	spin_unlock(&ci->lock);
1919 
1920 	return retval;
1921 }
1922 
1923 /**
1924  * udc_start: initialize gadget role
1925  * @ci: chipidea controller
1926  */
1927 static int udc_start(struct ci_hdrc *ci)
1928 {
1929 	struct device *dev = ci->dev;
1930 	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
1931 	int retval = 0;
1932 
1933 	ci->gadget.ops          = &usb_gadget_ops;
1934 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1935 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1936 	ci->gadget.name         = ci->platdata->name;
1937 	ci->gadget.otg_caps	= otg_caps;
1938 
1939 	if (ci->platdata->flags & CI_HDRC_REQUIRES_ALIGNED_DMA)
1940 		ci->gadget.quirk_avoids_skb_reserve = 1;
1941 
1942 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
1943 						otg_caps->adp_support))
1944 		ci->gadget.is_otg = 1;
1945 
1946 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1947 
1948 	/* alloc resources */
1949 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev->parent,
1950 				       sizeof(struct ci_hw_qh),
1951 				       64, CI_HDRC_PAGE_SIZE);
1952 	if (ci->qh_pool == NULL)
1953 		return -ENOMEM;
1954 
1955 	ci->td_pool = dma_pool_create("ci_hw_td", dev->parent,
1956 				       sizeof(struct ci_hw_td),
1957 				       64, CI_HDRC_PAGE_SIZE);
1958 	if (ci->td_pool == NULL) {
1959 		retval = -ENOMEM;
1960 		goto free_qh_pool;
1961 	}
1962 
1963 	retval = init_eps(ci);
1964 	if (retval)
1965 		goto free_pools;
1966 
1967 	ci->gadget.ep0 = &ci->ep0in->ep;
1968 
1969 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1970 	if (retval)
1971 		goto destroy_eps;
1972 
1973 	pm_runtime_no_callbacks(&ci->gadget.dev);
1974 	pm_runtime_enable(&ci->gadget.dev);
1975 
1976 	return retval;
1977 
1978 destroy_eps:
1979 	destroy_eps(ci);
1980 free_pools:
1981 	dma_pool_destroy(ci->td_pool);
1982 free_qh_pool:
1983 	dma_pool_destroy(ci->qh_pool);
1984 	return retval;
1985 }
1986 
1987 /**
1988  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1989  *
1990  * No interrupts active, the IRQ has been released
1991  */
1992 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1993 {
1994 	if (!ci->roles[CI_ROLE_GADGET])
1995 		return;
1996 
1997 	usb_del_gadget_udc(&ci->gadget);
1998 
1999 	destroy_eps(ci);
2000 
2001 	dma_pool_destroy(ci->td_pool);
2002 	dma_pool_destroy(ci->qh_pool);
2003 }
2004 
2005 static int udc_id_switch_for_device(struct ci_hdrc *ci)
2006 {
2007 	if (ci->platdata->pins_device)
2008 		pinctrl_select_state(ci->platdata->pctl,
2009 				     ci->platdata->pins_device);
2010 
2011 	if (ci->is_otg)
2012 		/* Clear and enable BSV irq */
2013 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
2014 					OTGSC_BSVIS | OTGSC_BSVIE);
2015 
2016 	return 0;
2017 }
2018 
2019 static void udc_id_switch_for_host(struct ci_hdrc *ci)
2020 {
2021 	/*
2022 	 * host doesn't care B_SESSION_VALID event
2023 	 * so clear and disbale BSV irq
2024 	 */
2025 	if (ci->is_otg)
2026 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
2027 
2028 	ci->vbus_active = 0;
2029 
2030 	if (ci->platdata->pins_device && ci->platdata->pins_default)
2031 		pinctrl_select_state(ci->platdata->pctl,
2032 				     ci->platdata->pins_default);
2033 }
2034 
2035 /**
2036  * ci_hdrc_gadget_init - initialize device related bits
2037  * ci: the controller
2038  *
2039  * This function initializes the gadget, if the device is "device capable".
2040  */
2041 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
2042 {
2043 	struct ci_role_driver *rdrv;
2044 	int ret;
2045 
2046 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
2047 		return -ENXIO;
2048 
2049 	rdrv = devm_kzalloc(ci->dev, sizeof(*rdrv), GFP_KERNEL);
2050 	if (!rdrv)
2051 		return -ENOMEM;
2052 
2053 	rdrv->start	= udc_id_switch_for_device;
2054 	rdrv->stop	= udc_id_switch_for_host;
2055 	rdrv->irq	= udc_irq;
2056 	rdrv->name	= "gadget";
2057 
2058 	ret = udc_start(ci);
2059 	if (!ret)
2060 		ci->roles[CI_ROLE_GADGET] = rdrv;
2061 
2062 	return ret;
2063 }
2064