xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision f7777dcc)
1 /*
2  * udc.c - ChipIdea UDC driver
3  *
4  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
5  *
6  * Author: David Lopo
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/dmapool.h>
16 #include <linux/err.h>
17 #include <linux/irqreturn.h>
18 #include <linux/kernel.h>
19 #include <linux/slab.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/usb/ch9.h>
22 #include <linux/usb/gadget.h>
23 #include <linux/usb/otg.h>
24 #include <linux/usb/chipidea.h>
25 
26 #include "ci.h"
27 #include "udc.h"
28 #include "bits.h"
29 #include "debug.h"
30 #include "otg.h"
31 
32 /* control endpoint description */
33 static const struct usb_endpoint_descriptor
34 ctrl_endpt_out_desc = {
35 	.bLength         = USB_DT_ENDPOINT_SIZE,
36 	.bDescriptorType = USB_DT_ENDPOINT,
37 
38 	.bEndpointAddress = USB_DIR_OUT,
39 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
40 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
41 };
42 
43 static const struct usb_endpoint_descriptor
44 ctrl_endpt_in_desc = {
45 	.bLength         = USB_DT_ENDPOINT_SIZE,
46 	.bDescriptorType = USB_DT_ENDPOINT,
47 
48 	.bEndpointAddress = USB_DIR_IN,
49 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
50 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
51 };
52 
53 /**
54  * hw_ep_bit: calculates the bit number
55  * @num: endpoint number
56  * @dir: endpoint direction
57  *
58  * This function returns bit number
59  */
60 static inline int hw_ep_bit(int num, int dir)
61 {
62 	return num + (dir ? 16 : 0);
63 }
64 
65 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
66 {
67 	int fill = 16 - ci->hw_ep_max / 2;
68 
69 	if (n >= ci->hw_ep_max / 2)
70 		n += fill;
71 
72 	return n;
73 }
74 
75 /**
76  * hw_device_state: enables/disables interrupts (execute without interruption)
77  * @dma: 0 => disable, !0 => enable and set dma engine
78  *
79  * This function returns an error code
80  */
81 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
82 {
83 	if (dma) {
84 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
85 		/* interrupt, error, port change, reset, sleep/suspend */
86 		hw_write(ci, OP_USBINTR, ~0,
87 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
88 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
89 	} else {
90 		hw_write(ci, OP_USBINTR, ~0, 0);
91 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
92 	}
93 	return 0;
94 }
95 
96 /**
97  * hw_ep_flush: flush endpoint fifo (execute without interruption)
98  * @num: endpoint number
99  * @dir: endpoint direction
100  *
101  * This function returns an error code
102  */
103 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
104 {
105 	int n = hw_ep_bit(num, dir);
106 
107 	do {
108 		/* flush any pending transfer */
109 		hw_write(ci, OP_ENDPTFLUSH, BIT(n), BIT(n));
110 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
111 			cpu_relax();
112 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
113 
114 	return 0;
115 }
116 
117 /**
118  * hw_ep_disable: disables endpoint (execute without interruption)
119  * @num: endpoint number
120  * @dir: endpoint direction
121  *
122  * This function returns an error code
123  */
124 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
125 {
126 	hw_ep_flush(ci, num, dir);
127 	hw_write(ci, OP_ENDPTCTRL + num,
128 		 dir ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
129 	return 0;
130 }
131 
132 /**
133  * hw_ep_enable: enables endpoint (execute without interruption)
134  * @num:  endpoint number
135  * @dir:  endpoint direction
136  * @type: endpoint type
137  *
138  * This function returns an error code
139  */
140 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
141 {
142 	u32 mask, data;
143 
144 	if (dir) {
145 		mask  = ENDPTCTRL_TXT;  /* type    */
146 		data  = type << __ffs(mask);
147 
148 		mask |= ENDPTCTRL_TXS;  /* unstall */
149 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
150 		data |= ENDPTCTRL_TXR;
151 		mask |= ENDPTCTRL_TXE;  /* enable  */
152 		data |= ENDPTCTRL_TXE;
153 	} else {
154 		mask  = ENDPTCTRL_RXT;  /* type    */
155 		data  = type << __ffs(mask);
156 
157 		mask |= ENDPTCTRL_RXS;  /* unstall */
158 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
159 		data |= ENDPTCTRL_RXR;
160 		mask |= ENDPTCTRL_RXE;  /* enable  */
161 		data |= ENDPTCTRL_RXE;
162 	}
163 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
164 	return 0;
165 }
166 
167 /**
168  * hw_ep_get_halt: return endpoint halt status
169  * @num: endpoint number
170  * @dir: endpoint direction
171  *
172  * This function returns 1 if endpoint halted
173  */
174 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
175 {
176 	u32 mask = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
177 
178 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
179 }
180 
181 /**
182  * hw_test_and_clear_setup_status: test & clear setup status (execute without
183  *                                 interruption)
184  * @n: endpoint number
185  *
186  * This function returns setup status
187  */
188 static int hw_test_and_clear_setup_status(struct ci_hdrc *ci, int n)
189 {
190 	n = ep_to_bit(ci, n);
191 	return hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(n));
192 }
193 
194 /**
195  * hw_ep_prime: primes endpoint (execute without interruption)
196  * @num:     endpoint number
197  * @dir:     endpoint direction
198  * @is_ctrl: true if control endpoint
199  *
200  * This function returns an error code
201  */
202 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
203 {
204 	int n = hw_ep_bit(num, dir);
205 
206 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
207 		return -EAGAIN;
208 
209 	hw_write(ci, OP_ENDPTPRIME, BIT(n), BIT(n));
210 
211 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
212 		cpu_relax();
213 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
214 		return -EAGAIN;
215 
216 	/* status shoult be tested according with manual but it doesn't work */
217 	return 0;
218 }
219 
220 /**
221  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
222  *                 without interruption)
223  * @num:   endpoint number
224  * @dir:   endpoint direction
225  * @value: true => stall, false => unstall
226  *
227  * This function returns an error code
228  */
229 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
230 {
231 	if (value != 0 && value != 1)
232 		return -EINVAL;
233 
234 	do {
235 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
236 		u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
237 		u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
238 
239 		/* data toggle - reserved for EP0 but it's in ESS */
240 		hw_write(ci, reg, mask_xs|mask_xr,
241 			  value ? mask_xs : mask_xr);
242 	} while (value != hw_ep_get_halt(ci, num, dir));
243 
244 	return 0;
245 }
246 
247 /**
248  * hw_is_port_high_speed: test if port is high speed
249  *
250  * This function returns true if high speed port
251  */
252 static int hw_port_is_high_speed(struct ci_hdrc *ci)
253 {
254 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
255 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
256 }
257 
258 /**
259  * hw_read_intr_enable: returns interrupt enable register
260  *
261  * This function returns register data
262  */
263 static u32 hw_read_intr_enable(struct ci_hdrc *ci)
264 {
265 	return hw_read(ci, OP_USBINTR, ~0);
266 }
267 
268 /**
269  * hw_read_intr_status: returns interrupt status register
270  *
271  * This function returns register data
272  */
273 static u32 hw_read_intr_status(struct ci_hdrc *ci)
274 {
275 	return hw_read(ci, OP_USBSTS, ~0);
276 }
277 
278 /**
279  * hw_test_and_clear_complete: test & clear complete status (execute without
280  *                             interruption)
281  * @n: endpoint number
282  *
283  * This function returns complete status
284  */
285 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
286 {
287 	n = ep_to_bit(ci, n);
288 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
289 }
290 
291 /**
292  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
293  *                                without interruption)
294  *
295  * This function returns active interrutps
296  */
297 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
298 {
299 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
300 
301 	hw_write(ci, OP_USBSTS, ~0, reg);
302 	return reg;
303 }
304 
305 /**
306  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
307  *                                interruption)
308  *
309  * This function returns guard value
310  */
311 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
312 {
313 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
314 }
315 
316 /**
317  * hw_test_and_set_setup_guard: test & set setup guard (execute without
318  *                              interruption)
319  *
320  * This function returns guard value
321  */
322 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
323 {
324 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
325 }
326 
327 /**
328  * hw_usb_set_address: configures USB address (execute without interruption)
329  * @value: new USB address
330  *
331  * This function explicitly sets the address, without the "USBADRA" (advance)
332  * feature, which is not supported by older versions of the controller.
333  */
334 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
335 {
336 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
337 		 value << __ffs(DEVICEADDR_USBADR));
338 }
339 
340 /**
341  * hw_usb_reset: restart device after a bus reset (execute without
342  *               interruption)
343  *
344  * This function returns an error code
345  */
346 static int hw_usb_reset(struct ci_hdrc *ci)
347 {
348 	hw_usb_set_address(ci, 0);
349 
350 	/* ESS flushes only at end?!? */
351 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
352 
353 	/* clear setup token semaphores */
354 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
355 
356 	/* clear complete status */
357 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
358 
359 	/* wait until all bits cleared */
360 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
361 		udelay(10);             /* not RTOS friendly */
362 
363 	/* reset all endpoints ? */
364 
365 	/* reset internal status and wait for further instructions
366 	   no need to verify the port reset status (ESS does it) */
367 
368 	return 0;
369 }
370 
371 /******************************************************************************
372  * UTIL block
373  *****************************************************************************/
374 
375 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
376 			  unsigned length)
377 {
378 	int i;
379 	u32 temp;
380 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
381 						  GFP_ATOMIC);
382 
383 	if (node == NULL)
384 		return -ENOMEM;
385 
386 	node->ptr = dma_pool_alloc(hwep->td_pool, GFP_ATOMIC,
387 				   &node->dma);
388 	if (node->ptr == NULL) {
389 		kfree(node);
390 		return -ENOMEM;
391 	}
392 
393 	memset(node->ptr, 0, sizeof(struct ci_hw_td));
394 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
395 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
396 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
397 
398 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
399 	if (length) {
400 		node->ptr->page[0] = cpu_to_le32(temp);
401 		for (i = 1; i < TD_PAGE_COUNT; i++) {
402 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
403 			page &= ~TD_RESERVED_MASK;
404 			node->ptr->page[i] = cpu_to_le32(page);
405 		}
406 	}
407 
408 	hwreq->req.actual += length;
409 
410 	if (!list_empty(&hwreq->tds)) {
411 		/* get the last entry */
412 		lastnode = list_entry(hwreq->tds.prev,
413 				struct td_node, td);
414 		lastnode->ptr->next = cpu_to_le32(node->dma);
415 	}
416 
417 	INIT_LIST_HEAD(&node->td);
418 	list_add_tail(&node->td, &hwreq->tds);
419 
420 	return 0;
421 }
422 
423 /**
424  * _usb_addr: calculates endpoint address from direction & number
425  * @ep:  endpoint
426  */
427 static inline u8 _usb_addr(struct ci_hw_ep *ep)
428 {
429 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
430 }
431 
432 /**
433  * _hardware_queue: configures a request at hardware level
434  * @gadget: gadget
435  * @hwep:   endpoint
436  *
437  * This function returns an error code
438  */
439 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
440 {
441 	struct ci_hdrc *ci = hwep->ci;
442 	int ret = 0;
443 	unsigned rest = hwreq->req.length;
444 	int pages = TD_PAGE_COUNT;
445 	struct td_node *firstnode, *lastnode;
446 
447 	/* don't queue twice */
448 	if (hwreq->req.status == -EALREADY)
449 		return -EALREADY;
450 
451 	hwreq->req.status = -EALREADY;
452 
453 	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
454 	if (ret)
455 		return ret;
456 
457 	/*
458 	 * The first buffer could be not page aligned.
459 	 * In that case we have to span into one extra td.
460 	 */
461 	if (hwreq->req.dma % PAGE_SIZE)
462 		pages--;
463 
464 	if (rest == 0)
465 		add_td_to_list(hwep, hwreq, 0);
466 
467 	while (rest > 0) {
468 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
469 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
470 		add_td_to_list(hwep, hwreq, count);
471 		rest -= count;
472 	}
473 
474 	if (hwreq->req.zero && hwreq->req.length
475 	    && (hwreq->req.length % hwep->ep.maxpacket == 0))
476 		add_td_to_list(hwep, hwreq, 0);
477 
478 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
479 
480 	lastnode = list_entry(hwreq->tds.prev,
481 		struct td_node, td);
482 
483 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
484 	if (!hwreq->req.no_interrupt)
485 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
486 	wmb();
487 
488 	hwreq->req.actual = 0;
489 	if (!list_empty(&hwep->qh.queue)) {
490 		struct ci_hw_req *hwreqprev;
491 		int n = hw_ep_bit(hwep->num, hwep->dir);
492 		int tmp_stat;
493 		struct td_node *prevlastnode;
494 		u32 next = firstnode->dma & TD_ADDR_MASK;
495 
496 		hwreqprev = list_entry(hwep->qh.queue.prev,
497 				struct ci_hw_req, queue);
498 		prevlastnode = list_entry(hwreqprev->tds.prev,
499 				struct td_node, td);
500 
501 		prevlastnode->ptr->next = cpu_to_le32(next);
502 		wmb();
503 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
504 			goto done;
505 		do {
506 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
507 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
508 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
509 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
510 		if (tmp_stat)
511 			goto done;
512 	}
513 
514 	/*  QH configuration */
515 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
516 	hwep->qh.ptr->td.token &=
517 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
518 
519 	if (hwep->type == USB_ENDPOINT_XFER_ISOC) {
520 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
521 
522 		if (hwreq->req.length % hwep->ep.maxpacket)
523 			mul++;
524 		hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
525 	}
526 
527 	wmb();   /* synchronize before ep prime */
528 
529 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
530 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
531 done:
532 	return ret;
533 }
534 
535 /*
536  * free_pending_td: remove a pending request for the endpoint
537  * @hwep: endpoint
538  */
539 static void free_pending_td(struct ci_hw_ep *hwep)
540 {
541 	struct td_node *pending = hwep->pending_td;
542 
543 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
544 	hwep->pending_td = NULL;
545 	kfree(pending);
546 }
547 
548 /**
549  * _hardware_dequeue: handles a request at hardware level
550  * @gadget: gadget
551  * @hwep:   endpoint
552  *
553  * This function returns an error code
554  */
555 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
556 {
557 	u32 tmptoken;
558 	struct td_node *node, *tmpnode;
559 	unsigned remaining_length;
560 	unsigned actual = hwreq->req.length;
561 
562 	if (hwreq->req.status != -EALREADY)
563 		return -EINVAL;
564 
565 	hwreq->req.status = 0;
566 
567 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
568 		tmptoken = le32_to_cpu(node->ptr->token);
569 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
570 			hwreq->req.status = -EALREADY;
571 			return -EBUSY;
572 		}
573 
574 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
575 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
576 		actual -= remaining_length;
577 
578 		hwreq->req.status = tmptoken & TD_STATUS;
579 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
580 			hwreq->req.status = -EPIPE;
581 			break;
582 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
583 			hwreq->req.status = -EPROTO;
584 			break;
585 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
586 			hwreq->req.status = -EILSEQ;
587 			break;
588 		}
589 
590 		if (remaining_length) {
591 			if (hwep->dir) {
592 				hwreq->req.status = -EPROTO;
593 				break;
594 			}
595 		}
596 		/*
597 		 * As the hardware could still address the freed td
598 		 * which will run the udc unusable, the cleanup of the
599 		 * td has to be delayed by one.
600 		 */
601 		if (hwep->pending_td)
602 			free_pending_td(hwep);
603 
604 		hwep->pending_td = node;
605 		list_del_init(&node->td);
606 	}
607 
608 	usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
609 
610 	hwreq->req.actual += actual;
611 
612 	if (hwreq->req.status)
613 		return hwreq->req.status;
614 
615 	return hwreq->req.actual;
616 }
617 
618 /**
619  * _ep_nuke: dequeues all endpoint requests
620  * @hwep: endpoint
621  *
622  * This function returns an error code
623  * Caller must hold lock
624  */
625 static int _ep_nuke(struct ci_hw_ep *hwep)
626 __releases(hwep->lock)
627 __acquires(hwep->lock)
628 {
629 	struct td_node *node, *tmpnode;
630 	if (hwep == NULL)
631 		return -EINVAL;
632 
633 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
634 
635 	while (!list_empty(&hwep->qh.queue)) {
636 
637 		/* pop oldest request */
638 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
639 						     struct ci_hw_req, queue);
640 
641 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
642 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
643 			list_del_init(&node->td);
644 			node->ptr = NULL;
645 			kfree(node);
646 		}
647 
648 		list_del_init(&hwreq->queue);
649 		hwreq->req.status = -ESHUTDOWN;
650 
651 		if (hwreq->req.complete != NULL) {
652 			spin_unlock(hwep->lock);
653 			hwreq->req.complete(&hwep->ep, &hwreq->req);
654 			spin_lock(hwep->lock);
655 		}
656 	}
657 
658 	if (hwep->pending_td)
659 		free_pending_td(hwep);
660 
661 	return 0;
662 }
663 
664 /**
665  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
666  * @gadget: gadget
667  *
668  * This function returns an error code
669  */
670 static int _gadget_stop_activity(struct usb_gadget *gadget)
671 {
672 	struct usb_ep *ep;
673 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
674 	unsigned long flags;
675 
676 	spin_lock_irqsave(&ci->lock, flags);
677 	ci->gadget.speed = USB_SPEED_UNKNOWN;
678 	ci->remote_wakeup = 0;
679 	ci->suspended = 0;
680 	spin_unlock_irqrestore(&ci->lock, flags);
681 
682 	/* flush all endpoints */
683 	gadget_for_each_ep(ep, gadget) {
684 		usb_ep_fifo_flush(ep);
685 	}
686 	usb_ep_fifo_flush(&ci->ep0out->ep);
687 	usb_ep_fifo_flush(&ci->ep0in->ep);
688 
689 	if (ci->driver)
690 		ci->driver->disconnect(gadget);
691 
692 	/* make sure to disable all endpoints */
693 	gadget_for_each_ep(ep, gadget) {
694 		usb_ep_disable(ep);
695 	}
696 
697 	if (ci->status != NULL) {
698 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
699 		ci->status = NULL;
700 	}
701 
702 	return 0;
703 }
704 
705 /******************************************************************************
706  * ISR block
707  *****************************************************************************/
708 /**
709  * isr_reset_handler: USB reset interrupt handler
710  * @ci: UDC device
711  *
712  * This function resets USB engine after a bus reset occurred
713  */
714 static void isr_reset_handler(struct ci_hdrc *ci)
715 __releases(ci->lock)
716 __acquires(ci->lock)
717 {
718 	int retval;
719 
720 	spin_unlock(&ci->lock);
721 	retval = _gadget_stop_activity(&ci->gadget);
722 	if (retval)
723 		goto done;
724 
725 	retval = hw_usb_reset(ci);
726 	if (retval)
727 		goto done;
728 
729 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
730 	if (ci->status == NULL)
731 		retval = -ENOMEM;
732 
733 done:
734 	spin_lock(&ci->lock);
735 
736 	if (retval)
737 		dev_err(ci->dev, "error: %i\n", retval);
738 }
739 
740 /**
741  * isr_get_status_complete: get_status request complete function
742  * @ep:  endpoint
743  * @req: request handled
744  *
745  * Caller must release lock
746  */
747 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
748 {
749 	if (ep == NULL || req == NULL)
750 		return;
751 
752 	kfree(req->buf);
753 	usb_ep_free_request(ep, req);
754 }
755 
756 /**
757  * _ep_queue: queues (submits) an I/O request to an endpoint
758  *
759  * Caller must hold lock
760  */
761 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
762 		    gfp_t __maybe_unused gfp_flags)
763 {
764 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
765 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
766 	struct ci_hdrc *ci = hwep->ci;
767 	int retval = 0;
768 
769 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
770 		return -EINVAL;
771 
772 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
773 		if (req->length)
774 			hwep = (ci->ep0_dir == RX) ?
775 			       ci->ep0out : ci->ep0in;
776 		if (!list_empty(&hwep->qh.queue)) {
777 			_ep_nuke(hwep);
778 			retval = -EOVERFLOW;
779 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
780 				 _usb_addr(hwep));
781 		}
782 	}
783 
784 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
785 	    hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
786 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
787 		return -EMSGSIZE;
788 	}
789 
790 	/* first nuke then test link, e.g. previous status has not sent */
791 	if (!list_empty(&hwreq->queue)) {
792 		dev_err(hwep->ci->dev, "request already in queue\n");
793 		return -EBUSY;
794 	}
795 
796 	/* push request */
797 	hwreq->req.status = -EINPROGRESS;
798 	hwreq->req.actual = 0;
799 
800 	retval = _hardware_enqueue(hwep, hwreq);
801 
802 	if (retval == -EALREADY)
803 		retval = 0;
804 	if (!retval)
805 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
806 
807 	return retval;
808 }
809 
810 /**
811  * isr_get_status_response: get_status request response
812  * @ci: ci struct
813  * @setup: setup request packet
814  *
815  * This function returns an error code
816  */
817 static int isr_get_status_response(struct ci_hdrc *ci,
818 				   struct usb_ctrlrequest *setup)
819 __releases(hwep->lock)
820 __acquires(hwep->lock)
821 {
822 	struct ci_hw_ep *hwep = ci->ep0in;
823 	struct usb_request *req = NULL;
824 	gfp_t gfp_flags = GFP_ATOMIC;
825 	int dir, num, retval;
826 
827 	if (hwep == NULL || setup == NULL)
828 		return -EINVAL;
829 
830 	spin_unlock(hwep->lock);
831 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
832 	spin_lock(hwep->lock);
833 	if (req == NULL)
834 		return -ENOMEM;
835 
836 	req->complete = isr_get_status_complete;
837 	req->length   = 2;
838 	req->buf      = kzalloc(req->length, gfp_flags);
839 	if (req->buf == NULL) {
840 		retval = -ENOMEM;
841 		goto err_free_req;
842 	}
843 
844 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
845 		/* Assume that device is bus powered for now. */
846 		*(u16 *)req->buf = ci->remote_wakeup << 1;
847 		retval = 0;
848 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
849 		   == USB_RECIP_ENDPOINT) {
850 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
851 			TX : RX;
852 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
853 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
854 	}
855 	/* else do nothing; reserved for future use */
856 
857 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
858 	if (retval)
859 		goto err_free_buf;
860 
861 	return 0;
862 
863  err_free_buf:
864 	kfree(req->buf);
865  err_free_req:
866 	spin_unlock(hwep->lock);
867 	usb_ep_free_request(&hwep->ep, req);
868 	spin_lock(hwep->lock);
869 	return retval;
870 }
871 
872 /**
873  * isr_setup_status_complete: setup_status request complete function
874  * @ep:  endpoint
875  * @req: request handled
876  *
877  * Caller must release lock. Put the port in test mode if test mode
878  * feature is selected.
879  */
880 static void
881 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
882 {
883 	struct ci_hdrc *ci = req->context;
884 	unsigned long flags;
885 
886 	if (ci->setaddr) {
887 		hw_usb_set_address(ci, ci->address);
888 		ci->setaddr = false;
889 	}
890 
891 	spin_lock_irqsave(&ci->lock, flags);
892 	if (ci->test_mode)
893 		hw_port_test_set(ci, ci->test_mode);
894 	spin_unlock_irqrestore(&ci->lock, flags);
895 }
896 
897 /**
898  * isr_setup_status_phase: queues the status phase of a setup transation
899  * @ci: ci struct
900  *
901  * This function returns an error code
902  */
903 static int isr_setup_status_phase(struct ci_hdrc *ci)
904 {
905 	int retval;
906 	struct ci_hw_ep *hwep;
907 
908 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
909 	ci->status->context = ci;
910 	ci->status->complete = isr_setup_status_complete;
911 
912 	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
913 
914 	return retval;
915 }
916 
917 /**
918  * isr_tr_complete_low: transaction complete low level handler
919  * @hwep: endpoint
920  *
921  * This function returns an error code
922  * Caller must hold lock
923  */
924 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
925 __releases(hwep->lock)
926 __acquires(hwep->lock)
927 {
928 	struct ci_hw_req *hwreq, *hwreqtemp;
929 	struct ci_hw_ep *hweptemp = hwep;
930 	int retval = 0;
931 
932 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
933 			queue) {
934 		retval = _hardware_dequeue(hwep, hwreq);
935 		if (retval < 0)
936 			break;
937 		list_del_init(&hwreq->queue);
938 		if (hwreq->req.complete != NULL) {
939 			spin_unlock(hwep->lock);
940 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
941 					hwreq->req.length)
942 				hweptemp = hwep->ci->ep0in;
943 			hwreq->req.complete(&hweptemp->ep, &hwreq->req);
944 			spin_lock(hwep->lock);
945 		}
946 	}
947 
948 	if (retval == -EBUSY)
949 		retval = 0;
950 
951 	return retval;
952 }
953 
954 /**
955  * isr_tr_complete_handler: transaction complete interrupt handler
956  * @ci: UDC descriptor
957  *
958  * This function handles traffic events
959  */
960 static void isr_tr_complete_handler(struct ci_hdrc *ci)
961 __releases(ci->lock)
962 __acquires(ci->lock)
963 {
964 	unsigned i;
965 	u8 tmode = 0;
966 
967 	for (i = 0; i < ci->hw_ep_max; i++) {
968 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
969 		int type, num, dir, err = -EINVAL;
970 		struct usb_ctrlrequest req;
971 
972 		if (hwep->ep.desc == NULL)
973 			continue;   /* not configured */
974 
975 		if (hw_test_and_clear_complete(ci, i)) {
976 			err = isr_tr_complete_low(hwep);
977 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
978 				if (err > 0)   /* needs status phase */
979 					err = isr_setup_status_phase(ci);
980 				if (err < 0) {
981 					spin_unlock(&ci->lock);
982 					if (usb_ep_set_halt(&hwep->ep))
983 						dev_err(ci->dev,
984 							"error: ep_set_halt\n");
985 					spin_lock(&ci->lock);
986 				}
987 			}
988 		}
989 
990 		if (hwep->type != USB_ENDPOINT_XFER_CONTROL ||
991 		    !hw_test_and_clear_setup_status(ci, i))
992 			continue;
993 
994 		if (i != 0) {
995 			dev_warn(ci->dev, "ctrl traffic at endpoint %d\n", i);
996 			continue;
997 		}
998 
999 		/*
1000 		 * Flush data and handshake transactions of previous
1001 		 * setup packet.
1002 		 */
1003 		_ep_nuke(ci->ep0out);
1004 		_ep_nuke(ci->ep0in);
1005 
1006 		/* read_setup_packet */
1007 		do {
1008 			hw_test_and_set_setup_guard(ci);
1009 			memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1010 		} while (!hw_test_and_clear_setup_guard(ci));
1011 
1012 		type = req.bRequestType;
1013 
1014 		ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1015 
1016 		switch (req.bRequest) {
1017 		case USB_REQ_CLEAR_FEATURE:
1018 			if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1019 					le16_to_cpu(req.wValue) ==
1020 					USB_ENDPOINT_HALT) {
1021 				if (req.wLength != 0)
1022 					break;
1023 				num  = le16_to_cpu(req.wIndex);
1024 				dir = num & USB_ENDPOINT_DIR_MASK;
1025 				num &= USB_ENDPOINT_NUMBER_MASK;
1026 				if (dir) /* TX */
1027 					num += ci->hw_ep_max/2;
1028 				if (!ci->ci_hw_ep[num].wedge) {
1029 					spin_unlock(&ci->lock);
1030 					err = usb_ep_clear_halt(
1031 						&ci->ci_hw_ep[num].ep);
1032 					spin_lock(&ci->lock);
1033 					if (err)
1034 						break;
1035 				}
1036 				err = isr_setup_status_phase(ci);
1037 			} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1038 					le16_to_cpu(req.wValue) ==
1039 					USB_DEVICE_REMOTE_WAKEUP) {
1040 				if (req.wLength != 0)
1041 					break;
1042 				ci->remote_wakeup = 0;
1043 				err = isr_setup_status_phase(ci);
1044 			} else {
1045 				goto delegate;
1046 			}
1047 			break;
1048 		case USB_REQ_GET_STATUS:
1049 			if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
1050 			    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1051 			    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1052 				goto delegate;
1053 			if (le16_to_cpu(req.wLength) != 2 ||
1054 			    le16_to_cpu(req.wValue)  != 0)
1055 				break;
1056 			err = isr_get_status_response(ci, &req);
1057 			break;
1058 		case USB_REQ_SET_ADDRESS:
1059 			if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1060 				goto delegate;
1061 			if (le16_to_cpu(req.wLength) != 0 ||
1062 			    le16_to_cpu(req.wIndex)  != 0)
1063 				break;
1064 			ci->address = (u8)le16_to_cpu(req.wValue);
1065 			ci->setaddr = true;
1066 			err = isr_setup_status_phase(ci);
1067 			break;
1068 		case USB_REQ_SET_FEATURE:
1069 			if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1070 					le16_to_cpu(req.wValue) ==
1071 					USB_ENDPOINT_HALT) {
1072 				if (req.wLength != 0)
1073 					break;
1074 				num  = le16_to_cpu(req.wIndex);
1075 				dir = num & USB_ENDPOINT_DIR_MASK;
1076 				num &= USB_ENDPOINT_NUMBER_MASK;
1077 				if (dir) /* TX */
1078 					num += ci->hw_ep_max/2;
1079 
1080 				spin_unlock(&ci->lock);
1081 				err = usb_ep_set_halt(&ci->ci_hw_ep[num].ep);
1082 				spin_lock(&ci->lock);
1083 				if (!err)
1084 					isr_setup_status_phase(ci);
1085 			} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1086 				if (req.wLength != 0)
1087 					break;
1088 				switch (le16_to_cpu(req.wValue)) {
1089 				case USB_DEVICE_REMOTE_WAKEUP:
1090 					ci->remote_wakeup = 1;
1091 					err = isr_setup_status_phase(ci);
1092 					break;
1093 				case USB_DEVICE_TEST_MODE:
1094 					tmode = le16_to_cpu(req.wIndex) >> 8;
1095 					switch (tmode) {
1096 					case TEST_J:
1097 					case TEST_K:
1098 					case TEST_SE0_NAK:
1099 					case TEST_PACKET:
1100 					case TEST_FORCE_EN:
1101 						ci->test_mode = tmode;
1102 						err = isr_setup_status_phase(
1103 								ci);
1104 						break;
1105 					default:
1106 						break;
1107 					}
1108 				default:
1109 					goto delegate;
1110 				}
1111 			} else {
1112 				goto delegate;
1113 			}
1114 			break;
1115 		default:
1116 delegate:
1117 			if (req.wLength == 0)   /* no data phase */
1118 				ci->ep0_dir = TX;
1119 
1120 			spin_unlock(&ci->lock);
1121 			err = ci->driver->setup(&ci->gadget, &req);
1122 			spin_lock(&ci->lock);
1123 			break;
1124 		}
1125 
1126 		if (err < 0) {
1127 			spin_unlock(&ci->lock);
1128 			if (usb_ep_set_halt(&hwep->ep))
1129 				dev_err(ci->dev, "error: ep_set_halt\n");
1130 			spin_lock(&ci->lock);
1131 		}
1132 	}
1133 }
1134 
1135 /******************************************************************************
1136  * ENDPT block
1137  *****************************************************************************/
1138 /**
1139  * ep_enable: configure endpoint, making it usable
1140  *
1141  * Check usb_ep_enable() at "usb_gadget.h" for details
1142  */
1143 static int ep_enable(struct usb_ep *ep,
1144 		     const struct usb_endpoint_descriptor *desc)
1145 {
1146 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1147 	int retval = 0;
1148 	unsigned long flags;
1149 	u32 cap = 0;
1150 
1151 	if (ep == NULL || desc == NULL)
1152 		return -EINVAL;
1153 
1154 	spin_lock_irqsave(hwep->lock, flags);
1155 
1156 	/* only internal SW should enable ctrl endpts */
1157 
1158 	hwep->ep.desc = desc;
1159 
1160 	if (!list_empty(&hwep->qh.queue))
1161 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1162 
1163 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1164 	hwep->num  = usb_endpoint_num(desc);
1165 	hwep->type = usb_endpoint_type(desc);
1166 
1167 	hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1168 	hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1169 
1170 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1171 		cap |= QH_IOS;
1172 	if (hwep->num)
1173 		cap |= QH_ZLT;
1174 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1175 
1176 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1177 
1178 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1179 
1180 	/*
1181 	 * Enable endpoints in the HW other than ep0 as ep0
1182 	 * is always enabled
1183 	 */
1184 	if (hwep->num)
1185 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1186 				       hwep->type);
1187 
1188 	spin_unlock_irqrestore(hwep->lock, flags);
1189 	return retval;
1190 }
1191 
1192 /**
1193  * ep_disable: endpoint is no longer usable
1194  *
1195  * Check usb_ep_disable() at "usb_gadget.h" for details
1196  */
1197 static int ep_disable(struct usb_ep *ep)
1198 {
1199 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1200 	int direction, retval = 0;
1201 	unsigned long flags;
1202 
1203 	if (ep == NULL)
1204 		return -EINVAL;
1205 	else if (hwep->ep.desc == NULL)
1206 		return -EBUSY;
1207 
1208 	spin_lock_irqsave(hwep->lock, flags);
1209 
1210 	/* only internal SW should disable ctrl endpts */
1211 
1212 	direction = hwep->dir;
1213 	do {
1214 		retval |= _ep_nuke(hwep);
1215 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1216 
1217 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1218 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1219 
1220 	} while (hwep->dir != direction);
1221 
1222 	hwep->ep.desc = NULL;
1223 
1224 	spin_unlock_irqrestore(hwep->lock, flags);
1225 	return retval;
1226 }
1227 
1228 /**
1229  * ep_alloc_request: allocate a request object to use with this endpoint
1230  *
1231  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1232  */
1233 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1234 {
1235 	struct ci_hw_req *hwreq = NULL;
1236 
1237 	if (ep == NULL)
1238 		return NULL;
1239 
1240 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1241 	if (hwreq != NULL) {
1242 		INIT_LIST_HEAD(&hwreq->queue);
1243 		INIT_LIST_HEAD(&hwreq->tds);
1244 	}
1245 
1246 	return (hwreq == NULL) ? NULL : &hwreq->req;
1247 }
1248 
1249 /**
1250  * ep_free_request: frees a request object
1251  *
1252  * Check usb_ep_free_request() at "usb_gadget.h" for details
1253  */
1254 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1255 {
1256 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1257 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1258 	struct td_node *node, *tmpnode;
1259 	unsigned long flags;
1260 
1261 	if (ep == NULL || req == NULL) {
1262 		return;
1263 	} else if (!list_empty(&hwreq->queue)) {
1264 		dev_err(hwep->ci->dev, "freeing queued request\n");
1265 		return;
1266 	}
1267 
1268 	spin_lock_irqsave(hwep->lock, flags);
1269 
1270 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1271 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1272 		list_del_init(&node->td);
1273 		node->ptr = NULL;
1274 		kfree(node);
1275 	}
1276 
1277 	kfree(hwreq);
1278 
1279 	spin_unlock_irqrestore(hwep->lock, flags);
1280 }
1281 
1282 /**
1283  * ep_queue: queues (submits) an I/O request to an endpoint
1284  *
1285  * Check usb_ep_queue()* at usb_gadget.h" for details
1286  */
1287 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1288 		    gfp_t __maybe_unused gfp_flags)
1289 {
1290 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1291 	int retval = 0;
1292 	unsigned long flags;
1293 
1294 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1295 		return -EINVAL;
1296 
1297 	spin_lock_irqsave(hwep->lock, flags);
1298 	retval = _ep_queue(ep, req, gfp_flags);
1299 	spin_unlock_irqrestore(hwep->lock, flags);
1300 	return retval;
1301 }
1302 
1303 /**
1304  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1305  *
1306  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1307  */
1308 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1309 {
1310 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1311 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1312 	unsigned long flags;
1313 
1314 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1315 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1316 		list_empty(&hwep->qh.queue))
1317 		return -EINVAL;
1318 
1319 	spin_lock_irqsave(hwep->lock, flags);
1320 
1321 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1322 
1323 	/* pop request */
1324 	list_del_init(&hwreq->queue);
1325 
1326 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1327 
1328 	req->status = -ECONNRESET;
1329 
1330 	if (hwreq->req.complete != NULL) {
1331 		spin_unlock(hwep->lock);
1332 		hwreq->req.complete(&hwep->ep, &hwreq->req);
1333 		spin_lock(hwep->lock);
1334 	}
1335 
1336 	spin_unlock_irqrestore(hwep->lock, flags);
1337 	return 0;
1338 }
1339 
1340 /**
1341  * ep_set_halt: sets the endpoint halt feature
1342  *
1343  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1344  */
1345 static int ep_set_halt(struct usb_ep *ep, int value)
1346 {
1347 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1348 	int direction, retval = 0;
1349 	unsigned long flags;
1350 
1351 	if (ep == NULL || hwep->ep.desc == NULL)
1352 		return -EINVAL;
1353 
1354 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
1355 		return -EOPNOTSUPP;
1356 
1357 	spin_lock_irqsave(hwep->lock, flags);
1358 
1359 #ifndef STALL_IN
1360 	/* g_file_storage MS compliant but g_zero fails chapter 9 compliance */
1361 	if (value && hwep->type == USB_ENDPOINT_XFER_BULK && hwep->dir == TX &&
1362 	    !list_empty(&hwep->qh.queue)) {
1363 		spin_unlock_irqrestore(hwep->lock, flags);
1364 		return -EAGAIN;
1365 	}
1366 #endif
1367 
1368 	direction = hwep->dir;
1369 	do {
1370 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
1371 
1372 		if (!value)
1373 			hwep->wedge = 0;
1374 
1375 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1376 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1377 
1378 	} while (hwep->dir != direction);
1379 
1380 	spin_unlock_irqrestore(hwep->lock, flags);
1381 	return retval;
1382 }
1383 
1384 /**
1385  * ep_set_wedge: sets the halt feature and ignores clear requests
1386  *
1387  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1388  */
1389 static int ep_set_wedge(struct usb_ep *ep)
1390 {
1391 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1392 	unsigned long flags;
1393 
1394 	if (ep == NULL || hwep->ep.desc == NULL)
1395 		return -EINVAL;
1396 
1397 	spin_lock_irqsave(hwep->lock, flags);
1398 	hwep->wedge = 1;
1399 	spin_unlock_irqrestore(hwep->lock, flags);
1400 
1401 	return usb_ep_set_halt(ep);
1402 }
1403 
1404 /**
1405  * ep_fifo_flush: flushes contents of a fifo
1406  *
1407  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1408  */
1409 static void ep_fifo_flush(struct usb_ep *ep)
1410 {
1411 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1412 	unsigned long flags;
1413 
1414 	if (ep == NULL) {
1415 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1416 		return;
1417 	}
1418 
1419 	spin_lock_irqsave(hwep->lock, flags);
1420 
1421 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1422 
1423 	spin_unlock_irqrestore(hwep->lock, flags);
1424 }
1425 
1426 /**
1427  * Endpoint-specific part of the API to the USB controller hardware
1428  * Check "usb_gadget.h" for details
1429  */
1430 static const struct usb_ep_ops usb_ep_ops = {
1431 	.enable	       = ep_enable,
1432 	.disable       = ep_disable,
1433 	.alloc_request = ep_alloc_request,
1434 	.free_request  = ep_free_request,
1435 	.queue	       = ep_queue,
1436 	.dequeue       = ep_dequeue,
1437 	.set_halt      = ep_set_halt,
1438 	.set_wedge     = ep_set_wedge,
1439 	.fifo_flush    = ep_fifo_flush,
1440 };
1441 
1442 /******************************************************************************
1443  * GADGET block
1444  *****************************************************************************/
1445 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1446 {
1447 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1448 	unsigned long flags;
1449 	int gadget_ready = 0;
1450 
1451 	spin_lock_irqsave(&ci->lock, flags);
1452 	ci->vbus_active = is_active;
1453 	if (ci->driver)
1454 		gadget_ready = 1;
1455 	spin_unlock_irqrestore(&ci->lock, flags);
1456 
1457 	if (gadget_ready) {
1458 		if (is_active) {
1459 			pm_runtime_get_sync(&_gadget->dev);
1460 			hw_device_reset(ci, USBMODE_CM_DC);
1461 			hw_device_state(ci, ci->ep0out->qh.dma);
1462 			dev_dbg(ci->dev, "Connected to host\n");
1463 		} else {
1464 			hw_device_state(ci, 0);
1465 			if (ci->platdata->notify_event)
1466 				ci->platdata->notify_event(ci,
1467 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1468 			_gadget_stop_activity(&ci->gadget);
1469 			pm_runtime_put_sync(&_gadget->dev);
1470 			dev_dbg(ci->dev, "Disconnected from host\n");
1471 		}
1472 	}
1473 
1474 	return 0;
1475 }
1476 
1477 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1478 {
1479 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1480 	unsigned long flags;
1481 	int ret = 0;
1482 
1483 	spin_lock_irqsave(&ci->lock, flags);
1484 	if (!ci->remote_wakeup) {
1485 		ret = -EOPNOTSUPP;
1486 		goto out;
1487 	}
1488 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1489 		ret = -EINVAL;
1490 		goto out;
1491 	}
1492 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1493 out:
1494 	spin_unlock_irqrestore(&ci->lock, flags);
1495 	return ret;
1496 }
1497 
1498 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1499 {
1500 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1501 
1502 	if (ci->transceiver)
1503 		return usb_phy_set_power(ci->transceiver, ma);
1504 	return -ENOTSUPP;
1505 }
1506 
1507 /* Change Data+ pullup status
1508  * this func is used by usb_gadget_connect/disconnet
1509  */
1510 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1511 {
1512 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1513 
1514 	if (!ci->vbus_active)
1515 		return -EOPNOTSUPP;
1516 
1517 	if (is_on)
1518 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1519 	else
1520 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1521 
1522 	return 0;
1523 }
1524 
1525 static int ci_udc_start(struct usb_gadget *gadget,
1526 			 struct usb_gadget_driver *driver);
1527 static int ci_udc_stop(struct usb_gadget *gadget,
1528 			struct usb_gadget_driver *driver);
1529 /**
1530  * Device operations part of the API to the USB controller hardware,
1531  * which don't involve endpoints (or i/o)
1532  * Check  "usb_gadget.h" for details
1533  */
1534 static const struct usb_gadget_ops usb_gadget_ops = {
1535 	.vbus_session	= ci_udc_vbus_session,
1536 	.wakeup		= ci_udc_wakeup,
1537 	.pullup		= ci_udc_pullup,
1538 	.vbus_draw	= ci_udc_vbus_draw,
1539 	.udc_start	= ci_udc_start,
1540 	.udc_stop	= ci_udc_stop,
1541 };
1542 
1543 static int init_eps(struct ci_hdrc *ci)
1544 {
1545 	int retval = 0, i, j;
1546 
1547 	for (i = 0; i < ci->hw_ep_max/2; i++)
1548 		for (j = RX; j <= TX; j++) {
1549 			int k = i + j * ci->hw_ep_max/2;
1550 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1551 
1552 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1553 					(j == TX)  ? "in" : "out");
1554 
1555 			hwep->ci          = ci;
1556 			hwep->lock         = &ci->lock;
1557 			hwep->td_pool      = ci->td_pool;
1558 
1559 			hwep->ep.name      = hwep->name;
1560 			hwep->ep.ops       = &usb_ep_ops;
1561 			/*
1562 			 * for ep0: maxP defined in desc, for other
1563 			 * eps, maxP is set by epautoconfig() called
1564 			 * by gadget layer
1565 			 */
1566 			hwep->ep.maxpacket = (unsigned short)~0;
1567 
1568 			INIT_LIST_HEAD(&hwep->qh.queue);
1569 			hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1570 						     &hwep->qh.dma);
1571 			if (hwep->qh.ptr == NULL)
1572 				retval = -ENOMEM;
1573 			else
1574 				memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1575 
1576 			/*
1577 			 * set up shorthands for ep0 out and in endpoints,
1578 			 * don't add to gadget's ep_list
1579 			 */
1580 			if (i == 0) {
1581 				if (j == RX)
1582 					ci->ep0out = hwep;
1583 				else
1584 					ci->ep0in = hwep;
1585 
1586 				hwep->ep.maxpacket = CTRL_PAYLOAD_MAX;
1587 				continue;
1588 			}
1589 
1590 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1591 		}
1592 
1593 	return retval;
1594 }
1595 
1596 static void destroy_eps(struct ci_hdrc *ci)
1597 {
1598 	int i;
1599 
1600 	for (i = 0; i < ci->hw_ep_max; i++) {
1601 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1602 
1603 		if (hwep->pending_td)
1604 			free_pending_td(hwep);
1605 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1606 	}
1607 }
1608 
1609 /**
1610  * ci_udc_start: register a gadget driver
1611  * @gadget: our gadget
1612  * @driver: the driver being registered
1613  *
1614  * Interrupts are enabled here.
1615  */
1616 static int ci_udc_start(struct usb_gadget *gadget,
1617 			 struct usb_gadget_driver *driver)
1618 {
1619 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1620 	unsigned long flags;
1621 	int retval = -ENOMEM;
1622 
1623 	if (driver->disconnect == NULL)
1624 		return -EINVAL;
1625 
1626 
1627 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1628 	retval = usb_ep_enable(&ci->ep0out->ep);
1629 	if (retval)
1630 		return retval;
1631 
1632 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1633 	retval = usb_ep_enable(&ci->ep0in->ep);
1634 	if (retval)
1635 		return retval;
1636 	spin_lock_irqsave(&ci->lock, flags);
1637 
1638 	ci->driver = driver;
1639 	pm_runtime_get_sync(&ci->gadget.dev);
1640 	if (ci->vbus_active) {
1641 		hw_device_reset(ci, USBMODE_CM_DC);
1642 	} else {
1643 		pm_runtime_put_sync(&ci->gadget.dev);
1644 		goto done;
1645 	}
1646 
1647 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1648 	if (retval)
1649 		pm_runtime_put_sync(&ci->gadget.dev);
1650 
1651  done:
1652 	spin_unlock_irqrestore(&ci->lock, flags);
1653 	return retval;
1654 }
1655 
1656 /**
1657  * ci_udc_stop: unregister a gadget driver
1658  */
1659 static int ci_udc_stop(struct usb_gadget *gadget,
1660 			struct usb_gadget_driver *driver)
1661 {
1662 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1663 	unsigned long flags;
1664 
1665 	spin_lock_irqsave(&ci->lock, flags);
1666 
1667 	if (ci->vbus_active) {
1668 		hw_device_state(ci, 0);
1669 		if (ci->platdata->notify_event)
1670 			ci->platdata->notify_event(ci,
1671 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1672 		spin_unlock_irqrestore(&ci->lock, flags);
1673 		_gadget_stop_activity(&ci->gadget);
1674 		spin_lock_irqsave(&ci->lock, flags);
1675 		pm_runtime_put(&ci->gadget.dev);
1676 	}
1677 
1678 	ci->driver = NULL;
1679 	spin_unlock_irqrestore(&ci->lock, flags);
1680 
1681 	return 0;
1682 }
1683 
1684 /******************************************************************************
1685  * BUS block
1686  *****************************************************************************/
1687 /**
1688  * udc_irq: ci interrupt handler
1689  *
1690  * This function returns IRQ_HANDLED if the IRQ has been handled
1691  * It locks access to registers
1692  */
1693 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1694 {
1695 	irqreturn_t retval;
1696 	u32 intr;
1697 
1698 	if (ci == NULL)
1699 		return IRQ_HANDLED;
1700 
1701 	spin_lock(&ci->lock);
1702 
1703 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1704 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1705 				USBMODE_CM_DC) {
1706 			spin_unlock(&ci->lock);
1707 			return IRQ_NONE;
1708 		}
1709 	}
1710 	intr = hw_test_and_clear_intr_active(ci);
1711 
1712 	if (intr) {
1713 		/* order defines priority - do NOT change it */
1714 		if (USBi_URI & intr)
1715 			isr_reset_handler(ci);
1716 
1717 		if (USBi_PCI & intr) {
1718 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1719 				USB_SPEED_HIGH : USB_SPEED_FULL;
1720 			if (ci->suspended && ci->driver->resume) {
1721 				spin_unlock(&ci->lock);
1722 				ci->driver->resume(&ci->gadget);
1723 				spin_lock(&ci->lock);
1724 				ci->suspended = 0;
1725 			}
1726 		}
1727 
1728 		if (USBi_UI  & intr)
1729 			isr_tr_complete_handler(ci);
1730 
1731 		if (USBi_SLI & intr) {
1732 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1733 			    ci->driver->suspend) {
1734 				ci->suspended = 1;
1735 				spin_unlock(&ci->lock);
1736 				ci->driver->suspend(&ci->gadget);
1737 				spin_lock(&ci->lock);
1738 			}
1739 		}
1740 		retval = IRQ_HANDLED;
1741 	} else {
1742 		retval = IRQ_NONE;
1743 	}
1744 	spin_unlock(&ci->lock);
1745 
1746 	return retval;
1747 }
1748 
1749 /**
1750  * udc_start: initialize gadget role
1751  * @ci: chipidea controller
1752  */
1753 static int udc_start(struct ci_hdrc *ci)
1754 {
1755 	struct device *dev = ci->dev;
1756 	int retval = 0;
1757 
1758 	spin_lock_init(&ci->lock);
1759 
1760 	ci->gadget.ops          = &usb_gadget_ops;
1761 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1762 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1763 	ci->gadget.is_otg       = 0;
1764 	ci->gadget.name         = ci->platdata->name;
1765 
1766 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1767 
1768 	/* alloc resources */
1769 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1770 				       sizeof(struct ci_hw_qh),
1771 				       64, CI_HDRC_PAGE_SIZE);
1772 	if (ci->qh_pool == NULL)
1773 		return -ENOMEM;
1774 
1775 	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1776 				       sizeof(struct ci_hw_td),
1777 				       64, CI_HDRC_PAGE_SIZE);
1778 	if (ci->td_pool == NULL) {
1779 		retval = -ENOMEM;
1780 		goto free_qh_pool;
1781 	}
1782 
1783 	retval = init_eps(ci);
1784 	if (retval)
1785 		goto free_pools;
1786 
1787 	ci->gadget.ep0 = &ci->ep0in->ep;
1788 
1789 	if (ci->global_phy) {
1790 		ci->transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
1791 		if (IS_ERR(ci->transceiver))
1792 			ci->transceiver = NULL;
1793 	}
1794 
1795 	if (ci->platdata->flags & CI_HDRC_REQUIRE_TRANSCEIVER) {
1796 		if (ci->transceiver == NULL) {
1797 			retval = -ENODEV;
1798 			goto destroy_eps;
1799 		}
1800 	}
1801 
1802 	if (ci->transceiver) {
1803 		retval = otg_set_peripheral(ci->transceiver->otg,
1804 						&ci->gadget);
1805 		/*
1806 		 * If we implement all USB functions using chipidea drivers,
1807 		 * it doesn't need to call above API, meanwhile, if we only
1808 		 * use gadget function, calling above API is useless.
1809 		 */
1810 		if (retval && retval != -ENOTSUPP)
1811 			goto put_transceiver;
1812 	}
1813 
1814 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1815 	if (retval)
1816 		goto remove_trans;
1817 
1818 	pm_runtime_no_callbacks(&ci->gadget.dev);
1819 	pm_runtime_enable(&ci->gadget.dev);
1820 
1821 	/* Update ci->vbus_active */
1822 	ci_handle_vbus_change(ci);
1823 
1824 	return retval;
1825 
1826 remove_trans:
1827 	if (ci->transceiver) {
1828 		otg_set_peripheral(ci->transceiver->otg, NULL);
1829 		if (ci->global_phy)
1830 			usb_put_phy(ci->transceiver);
1831 	}
1832 
1833 	dev_err(dev, "error = %i\n", retval);
1834 put_transceiver:
1835 	if (ci->transceiver && ci->global_phy)
1836 		usb_put_phy(ci->transceiver);
1837 destroy_eps:
1838 	destroy_eps(ci);
1839 free_pools:
1840 	dma_pool_destroy(ci->td_pool);
1841 free_qh_pool:
1842 	dma_pool_destroy(ci->qh_pool);
1843 	return retval;
1844 }
1845 
1846 /**
1847  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1848  *
1849  * No interrupts active, the IRQ has been released
1850  */
1851 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1852 {
1853 	if (!ci->roles[CI_ROLE_GADGET])
1854 		return;
1855 
1856 	usb_del_gadget_udc(&ci->gadget);
1857 
1858 	destroy_eps(ci);
1859 
1860 	dma_pool_destroy(ci->td_pool);
1861 	dma_pool_destroy(ci->qh_pool);
1862 
1863 	if (ci->transceiver) {
1864 		otg_set_peripheral(ci->transceiver->otg, NULL);
1865 		if (ci->global_phy)
1866 			usb_put_phy(ci->transceiver);
1867 	}
1868 }
1869 
1870 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1871 {
1872 	if (ci->is_otg) {
1873 		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
1874 		ci_enable_otg_interrupt(ci, OTGSC_BSVIE);
1875 	}
1876 
1877 	return 0;
1878 }
1879 
1880 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1881 {
1882 	if (ci->is_otg) {
1883 		/* host doesn't care B_SESSION_VALID event */
1884 		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
1885 		ci_disable_otg_interrupt(ci, OTGSC_BSVIE);
1886 	}
1887 }
1888 
1889 /**
1890  * ci_hdrc_gadget_init - initialize device related bits
1891  * ci: the controller
1892  *
1893  * This function initializes the gadget, if the device is "device capable".
1894  */
1895 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1896 {
1897 	struct ci_role_driver *rdrv;
1898 
1899 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1900 		return -ENXIO;
1901 
1902 	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1903 	if (!rdrv)
1904 		return -ENOMEM;
1905 
1906 	rdrv->start	= udc_id_switch_for_device;
1907 	rdrv->stop	= udc_id_switch_for_host;
1908 	rdrv->irq	= udc_irq;
1909 	rdrv->name	= "gadget";
1910 	ci->roles[CI_ROLE_GADGET] = rdrv;
1911 
1912 	return udc_start(ci);
1913 }
1914