xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision 6c870213d6f3a25981c10728f46294a3bed1703f)
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/chipidea.h>
24 
25 #include "ci.h"
26 #include "udc.h"
27 #include "bits.h"
28 #include "debug.h"
29 #include "otg.h"
30 
31 /* control endpoint description */
32 static const struct usb_endpoint_descriptor
33 ctrl_endpt_out_desc = {
34 	.bLength         = USB_DT_ENDPOINT_SIZE,
35 	.bDescriptorType = USB_DT_ENDPOINT,
36 
37 	.bEndpointAddress = USB_DIR_OUT,
38 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
39 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
40 };
41 
42 static const struct usb_endpoint_descriptor
43 ctrl_endpt_in_desc = {
44 	.bLength         = USB_DT_ENDPOINT_SIZE,
45 	.bDescriptorType = USB_DT_ENDPOINT,
46 
47 	.bEndpointAddress = USB_DIR_IN,
48 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
49 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
50 };
51 
52 /**
53  * hw_ep_bit: calculates the bit number
54  * @num: endpoint number
55  * @dir: endpoint direction
56  *
57  * This function returns bit number
58  */
59 static inline int hw_ep_bit(int num, int dir)
60 {
61 	return num + (dir ? 16 : 0);
62 }
63 
64 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
65 {
66 	int fill = 16 - ci->hw_ep_max / 2;
67 
68 	if (n >= ci->hw_ep_max / 2)
69 		n += fill;
70 
71 	return n;
72 }
73 
74 /**
75  * hw_device_state: enables/disables interrupts (execute without interruption)
76  * @dma: 0 => disable, !0 => enable and set dma engine
77  *
78  * This function returns an error code
79  */
80 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
81 {
82 	if (dma) {
83 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
84 		/* interrupt, error, port change, reset, sleep/suspend */
85 		hw_write(ci, OP_USBINTR, ~0,
86 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
87 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
88 	} else {
89 		hw_write(ci, OP_USBINTR, ~0, 0);
90 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
91 	}
92 	return 0;
93 }
94 
95 /**
96  * hw_ep_flush: flush endpoint fifo (execute without interruption)
97  * @num: endpoint number
98  * @dir: endpoint direction
99  *
100  * This function returns an error code
101  */
102 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
103 {
104 	int n = hw_ep_bit(num, dir);
105 
106 	do {
107 		/* flush any pending transfer */
108 		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
109 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
110 			cpu_relax();
111 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
112 
113 	return 0;
114 }
115 
116 /**
117  * hw_ep_disable: disables endpoint (execute without interruption)
118  * @num: endpoint number
119  * @dir: endpoint direction
120  *
121  * This function returns an error code
122  */
123 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
124 {
125 	hw_ep_flush(ci, num, dir);
126 	hw_write(ci, OP_ENDPTCTRL + num,
127 		 dir ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
128 	return 0;
129 }
130 
131 /**
132  * hw_ep_enable: enables endpoint (execute without interruption)
133  * @num:  endpoint number
134  * @dir:  endpoint direction
135  * @type: endpoint type
136  *
137  * This function returns an error code
138  */
139 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
140 {
141 	u32 mask, data;
142 
143 	if (dir) {
144 		mask  = ENDPTCTRL_TXT;  /* type    */
145 		data  = type << __ffs(mask);
146 
147 		mask |= ENDPTCTRL_TXS;  /* unstall */
148 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
149 		data |= ENDPTCTRL_TXR;
150 		mask |= ENDPTCTRL_TXE;  /* enable  */
151 		data |= ENDPTCTRL_TXE;
152 	} else {
153 		mask  = ENDPTCTRL_RXT;  /* type    */
154 		data  = type << __ffs(mask);
155 
156 		mask |= ENDPTCTRL_RXS;  /* unstall */
157 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
158 		data |= ENDPTCTRL_RXR;
159 		mask |= ENDPTCTRL_RXE;  /* enable  */
160 		data |= ENDPTCTRL_RXE;
161 	}
162 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
163 	return 0;
164 }
165 
166 /**
167  * hw_ep_get_halt: return endpoint halt status
168  * @num: endpoint number
169  * @dir: endpoint direction
170  *
171  * This function returns 1 if endpoint halted
172  */
173 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
174 {
175 	u32 mask = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
176 
177 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
178 }
179 
180 /**
181  * hw_ep_prime: primes endpoint (execute without interruption)
182  * @num:     endpoint number
183  * @dir:     endpoint direction
184  * @is_ctrl: true if control endpoint
185  *
186  * This function returns an error code
187  */
188 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
189 {
190 	int n = hw_ep_bit(num, dir);
191 
192 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
193 		return -EAGAIN;
194 
195 	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
196 
197 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
198 		cpu_relax();
199 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
200 		return -EAGAIN;
201 
202 	/* status shoult be tested according with manual but it doesn't work */
203 	return 0;
204 }
205 
206 /**
207  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
208  *                 without interruption)
209  * @num:   endpoint number
210  * @dir:   endpoint direction
211  * @value: true => stall, false => unstall
212  *
213  * This function returns an error code
214  */
215 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
216 {
217 	if (value != 0 && value != 1)
218 		return -EINVAL;
219 
220 	do {
221 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
222 		u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
223 		u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
224 
225 		/* data toggle - reserved for EP0 but it's in ESS */
226 		hw_write(ci, reg, mask_xs|mask_xr,
227 			  value ? mask_xs : mask_xr);
228 	} while (value != hw_ep_get_halt(ci, num, dir));
229 
230 	return 0;
231 }
232 
233 /**
234  * hw_is_port_high_speed: test if port is high speed
235  *
236  * This function returns true if high speed port
237  */
238 static int hw_port_is_high_speed(struct ci_hdrc *ci)
239 {
240 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
241 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
242 }
243 
244 /**
245  * hw_read_intr_enable: returns interrupt enable register
246  *
247  * This function returns register data
248  */
249 static u32 hw_read_intr_enable(struct ci_hdrc *ci)
250 {
251 	return hw_read(ci, OP_USBINTR, ~0);
252 }
253 
254 /**
255  * hw_read_intr_status: returns interrupt status register
256  *
257  * This function returns register data
258  */
259 static u32 hw_read_intr_status(struct ci_hdrc *ci)
260 {
261 	return hw_read(ci, OP_USBSTS, ~0);
262 }
263 
264 /**
265  * hw_test_and_clear_complete: test & clear complete status (execute without
266  *                             interruption)
267  * @n: endpoint number
268  *
269  * This function returns complete status
270  */
271 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
272 {
273 	n = ep_to_bit(ci, n);
274 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
275 }
276 
277 /**
278  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
279  *                                without interruption)
280  *
281  * This function returns active interrutps
282  */
283 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
284 {
285 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
286 
287 	hw_write(ci, OP_USBSTS, ~0, reg);
288 	return reg;
289 }
290 
291 /**
292  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
293  *                                interruption)
294  *
295  * This function returns guard value
296  */
297 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
298 {
299 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
300 }
301 
302 /**
303  * hw_test_and_set_setup_guard: test & set setup guard (execute without
304  *                              interruption)
305  *
306  * This function returns guard value
307  */
308 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
309 {
310 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
311 }
312 
313 /**
314  * hw_usb_set_address: configures USB address (execute without interruption)
315  * @value: new USB address
316  *
317  * This function explicitly sets the address, without the "USBADRA" (advance)
318  * feature, which is not supported by older versions of the controller.
319  */
320 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
321 {
322 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
323 		 value << __ffs(DEVICEADDR_USBADR));
324 }
325 
326 /**
327  * hw_usb_reset: restart device after a bus reset (execute without
328  *               interruption)
329  *
330  * This function returns an error code
331  */
332 static int hw_usb_reset(struct ci_hdrc *ci)
333 {
334 	hw_usb_set_address(ci, 0);
335 
336 	/* ESS flushes only at end?!? */
337 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
338 
339 	/* clear setup token semaphores */
340 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
341 
342 	/* clear complete status */
343 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
344 
345 	/* wait until all bits cleared */
346 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
347 		udelay(10);             /* not RTOS friendly */
348 
349 	/* reset all endpoints ? */
350 
351 	/* reset internal status and wait for further instructions
352 	   no need to verify the port reset status (ESS does it) */
353 
354 	return 0;
355 }
356 
357 /******************************************************************************
358  * UTIL block
359  *****************************************************************************/
360 
361 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
362 			  unsigned length)
363 {
364 	int i;
365 	u32 temp;
366 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
367 						  GFP_ATOMIC);
368 
369 	if (node == NULL)
370 		return -ENOMEM;
371 
372 	node->ptr = dma_pool_alloc(hwep->td_pool, GFP_ATOMIC,
373 				   &node->dma);
374 	if (node->ptr == NULL) {
375 		kfree(node);
376 		return -ENOMEM;
377 	}
378 
379 	memset(node->ptr, 0, sizeof(struct ci_hw_td));
380 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
381 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
382 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
383 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
384 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
385 
386 		if (hwreq->req.length == 0
387 				|| hwreq->req.length % hwep->ep.maxpacket)
388 			mul++;
389 		node->ptr->token |= mul << __ffs(TD_MULTO);
390 	}
391 
392 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
393 	if (length) {
394 		node->ptr->page[0] = cpu_to_le32(temp);
395 		for (i = 1; i < TD_PAGE_COUNT; i++) {
396 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
397 			page &= ~TD_RESERVED_MASK;
398 			node->ptr->page[i] = cpu_to_le32(page);
399 		}
400 	}
401 
402 	hwreq->req.actual += length;
403 
404 	if (!list_empty(&hwreq->tds)) {
405 		/* get the last entry */
406 		lastnode = list_entry(hwreq->tds.prev,
407 				struct td_node, td);
408 		lastnode->ptr->next = cpu_to_le32(node->dma);
409 	}
410 
411 	INIT_LIST_HEAD(&node->td);
412 	list_add_tail(&node->td, &hwreq->tds);
413 
414 	return 0;
415 }
416 
417 /**
418  * _usb_addr: calculates endpoint address from direction & number
419  * @ep:  endpoint
420  */
421 static inline u8 _usb_addr(struct ci_hw_ep *ep)
422 {
423 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
424 }
425 
426 /**
427  * _hardware_queue: configures a request at hardware level
428  * @gadget: gadget
429  * @hwep:   endpoint
430  *
431  * This function returns an error code
432  */
433 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
434 {
435 	struct ci_hdrc *ci = hwep->ci;
436 	int ret = 0;
437 	unsigned rest = hwreq->req.length;
438 	int pages = TD_PAGE_COUNT;
439 	struct td_node *firstnode, *lastnode;
440 
441 	/* don't queue twice */
442 	if (hwreq->req.status == -EALREADY)
443 		return -EALREADY;
444 
445 	hwreq->req.status = -EALREADY;
446 
447 	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
448 	if (ret)
449 		return ret;
450 
451 	/*
452 	 * The first buffer could be not page aligned.
453 	 * In that case we have to span into one extra td.
454 	 */
455 	if (hwreq->req.dma % PAGE_SIZE)
456 		pages--;
457 
458 	if (rest == 0)
459 		add_td_to_list(hwep, hwreq, 0);
460 
461 	while (rest > 0) {
462 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
463 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
464 		add_td_to_list(hwep, hwreq, count);
465 		rest -= count;
466 	}
467 
468 	if (hwreq->req.zero && hwreq->req.length
469 	    && (hwreq->req.length % hwep->ep.maxpacket == 0))
470 		add_td_to_list(hwep, hwreq, 0);
471 
472 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
473 
474 	lastnode = list_entry(hwreq->tds.prev,
475 		struct td_node, td);
476 
477 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
478 	if (!hwreq->req.no_interrupt)
479 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
480 	wmb();
481 
482 	hwreq->req.actual = 0;
483 	if (!list_empty(&hwep->qh.queue)) {
484 		struct ci_hw_req *hwreqprev;
485 		int n = hw_ep_bit(hwep->num, hwep->dir);
486 		int tmp_stat;
487 		struct td_node *prevlastnode;
488 		u32 next = firstnode->dma & TD_ADDR_MASK;
489 
490 		hwreqprev = list_entry(hwep->qh.queue.prev,
491 				struct ci_hw_req, queue);
492 		prevlastnode = list_entry(hwreqprev->tds.prev,
493 				struct td_node, td);
494 
495 		prevlastnode->ptr->next = cpu_to_le32(next);
496 		wmb();
497 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
498 			goto done;
499 		do {
500 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
501 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
502 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
503 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
504 		if (tmp_stat)
505 			goto done;
506 	}
507 
508 	/*  QH configuration */
509 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
510 	hwep->qh.ptr->td.token &=
511 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
512 
513 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
514 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
515 
516 		if (hwreq->req.length == 0
517 				|| hwreq->req.length % hwep->ep.maxpacket)
518 			mul++;
519 		hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
520 	}
521 
522 	wmb();   /* synchronize before ep prime */
523 
524 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
525 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
526 done:
527 	return ret;
528 }
529 
530 /*
531  * free_pending_td: remove a pending request for the endpoint
532  * @hwep: endpoint
533  */
534 static void free_pending_td(struct ci_hw_ep *hwep)
535 {
536 	struct td_node *pending = hwep->pending_td;
537 
538 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
539 	hwep->pending_td = NULL;
540 	kfree(pending);
541 }
542 
543 /**
544  * _hardware_dequeue: handles a request at hardware level
545  * @gadget: gadget
546  * @hwep:   endpoint
547  *
548  * This function returns an error code
549  */
550 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
551 {
552 	u32 tmptoken;
553 	struct td_node *node, *tmpnode;
554 	unsigned remaining_length;
555 	unsigned actual = hwreq->req.length;
556 
557 	if (hwreq->req.status != -EALREADY)
558 		return -EINVAL;
559 
560 	hwreq->req.status = 0;
561 
562 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
563 		tmptoken = le32_to_cpu(node->ptr->token);
564 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
565 			hwreq->req.status = -EALREADY;
566 			return -EBUSY;
567 		}
568 
569 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
570 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
571 		actual -= remaining_length;
572 
573 		hwreq->req.status = tmptoken & TD_STATUS;
574 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
575 			hwreq->req.status = -EPIPE;
576 			break;
577 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
578 			hwreq->req.status = -EPROTO;
579 			break;
580 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
581 			hwreq->req.status = -EILSEQ;
582 			break;
583 		}
584 
585 		if (remaining_length) {
586 			if (hwep->dir) {
587 				hwreq->req.status = -EPROTO;
588 				break;
589 			}
590 		}
591 		/*
592 		 * As the hardware could still address the freed td
593 		 * which will run the udc unusable, the cleanup of the
594 		 * td has to be delayed by one.
595 		 */
596 		if (hwep->pending_td)
597 			free_pending_td(hwep);
598 
599 		hwep->pending_td = node;
600 		list_del_init(&node->td);
601 	}
602 
603 	usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
604 
605 	hwreq->req.actual += actual;
606 
607 	if (hwreq->req.status)
608 		return hwreq->req.status;
609 
610 	return hwreq->req.actual;
611 }
612 
613 /**
614  * _ep_nuke: dequeues all endpoint requests
615  * @hwep: endpoint
616  *
617  * This function returns an error code
618  * Caller must hold lock
619  */
620 static int _ep_nuke(struct ci_hw_ep *hwep)
621 __releases(hwep->lock)
622 __acquires(hwep->lock)
623 {
624 	struct td_node *node, *tmpnode;
625 	if (hwep == NULL)
626 		return -EINVAL;
627 
628 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
629 
630 	while (!list_empty(&hwep->qh.queue)) {
631 
632 		/* pop oldest request */
633 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
634 						     struct ci_hw_req, queue);
635 
636 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
637 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
638 			list_del_init(&node->td);
639 			node->ptr = NULL;
640 			kfree(node);
641 		}
642 
643 		list_del_init(&hwreq->queue);
644 		hwreq->req.status = -ESHUTDOWN;
645 
646 		if (hwreq->req.complete != NULL) {
647 			spin_unlock(hwep->lock);
648 			hwreq->req.complete(&hwep->ep, &hwreq->req);
649 			spin_lock(hwep->lock);
650 		}
651 	}
652 
653 	if (hwep->pending_td)
654 		free_pending_td(hwep);
655 
656 	return 0;
657 }
658 
659 /**
660  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
661  * @gadget: gadget
662  *
663  * This function returns an error code
664  */
665 static int _gadget_stop_activity(struct usb_gadget *gadget)
666 {
667 	struct usb_ep *ep;
668 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
669 	unsigned long flags;
670 
671 	spin_lock_irqsave(&ci->lock, flags);
672 	ci->gadget.speed = USB_SPEED_UNKNOWN;
673 	ci->remote_wakeup = 0;
674 	ci->suspended = 0;
675 	spin_unlock_irqrestore(&ci->lock, flags);
676 
677 	/* flush all endpoints */
678 	gadget_for_each_ep(ep, gadget) {
679 		usb_ep_fifo_flush(ep);
680 	}
681 	usb_ep_fifo_flush(&ci->ep0out->ep);
682 	usb_ep_fifo_flush(&ci->ep0in->ep);
683 
684 	/* make sure to disable all endpoints */
685 	gadget_for_each_ep(ep, gadget) {
686 		usb_ep_disable(ep);
687 	}
688 
689 	if (ci->status != NULL) {
690 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
691 		ci->status = NULL;
692 	}
693 
694 	return 0;
695 }
696 
697 /******************************************************************************
698  * ISR block
699  *****************************************************************************/
700 /**
701  * isr_reset_handler: USB reset interrupt handler
702  * @ci: UDC device
703  *
704  * This function resets USB engine after a bus reset occurred
705  */
706 static void isr_reset_handler(struct ci_hdrc *ci)
707 __releases(ci->lock)
708 __acquires(ci->lock)
709 {
710 	int retval;
711 
712 	spin_unlock(&ci->lock);
713 	if (ci->gadget.speed != USB_SPEED_UNKNOWN) {
714 		if (ci->driver)
715 			ci->driver->disconnect(&ci->gadget);
716 	}
717 
718 	retval = _gadget_stop_activity(&ci->gadget);
719 	if (retval)
720 		goto done;
721 
722 	retval = hw_usb_reset(ci);
723 	if (retval)
724 		goto done;
725 
726 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
727 	if (ci->status == NULL)
728 		retval = -ENOMEM;
729 
730 done:
731 	spin_lock(&ci->lock);
732 
733 	if (retval)
734 		dev_err(ci->dev, "error: %i\n", retval);
735 }
736 
737 /**
738  * isr_get_status_complete: get_status request complete function
739  * @ep:  endpoint
740  * @req: request handled
741  *
742  * Caller must release lock
743  */
744 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
745 {
746 	if (ep == NULL || req == NULL)
747 		return;
748 
749 	kfree(req->buf);
750 	usb_ep_free_request(ep, req);
751 }
752 
753 /**
754  * _ep_queue: queues (submits) an I/O request to an endpoint
755  *
756  * Caller must hold lock
757  */
758 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
759 		    gfp_t __maybe_unused gfp_flags)
760 {
761 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
762 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
763 	struct ci_hdrc *ci = hwep->ci;
764 	int retval = 0;
765 
766 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
767 		return -EINVAL;
768 
769 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
770 		if (req->length)
771 			hwep = (ci->ep0_dir == RX) ?
772 			       ci->ep0out : ci->ep0in;
773 		if (!list_empty(&hwep->qh.queue)) {
774 			_ep_nuke(hwep);
775 			retval = -EOVERFLOW;
776 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
777 				 _usb_addr(hwep));
778 		}
779 	}
780 
781 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
782 	    hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
783 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
784 		return -EMSGSIZE;
785 	}
786 
787 	/* first nuke then test link, e.g. previous status has not sent */
788 	if (!list_empty(&hwreq->queue)) {
789 		dev_err(hwep->ci->dev, "request already in queue\n");
790 		return -EBUSY;
791 	}
792 
793 	/* push request */
794 	hwreq->req.status = -EINPROGRESS;
795 	hwreq->req.actual = 0;
796 
797 	retval = _hardware_enqueue(hwep, hwreq);
798 
799 	if (retval == -EALREADY)
800 		retval = 0;
801 	if (!retval)
802 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
803 
804 	return retval;
805 }
806 
807 /**
808  * isr_get_status_response: get_status request response
809  * @ci: ci struct
810  * @setup: setup request packet
811  *
812  * This function returns an error code
813  */
814 static int isr_get_status_response(struct ci_hdrc *ci,
815 				   struct usb_ctrlrequest *setup)
816 __releases(hwep->lock)
817 __acquires(hwep->lock)
818 {
819 	struct ci_hw_ep *hwep = ci->ep0in;
820 	struct usb_request *req = NULL;
821 	gfp_t gfp_flags = GFP_ATOMIC;
822 	int dir, num, retval;
823 
824 	if (hwep == NULL || setup == NULL)
825 		return -EINVAL;
826 
827 	spin_unlock(hwep->lock);
828 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
829 	spin_lock(hwep->lock);
830 	if (req == NULL)
831 		return -ENOMEM;
832 
833 	req->complete = isr_get_status_complete;
834 	req->length   = 2;
835 	req->buf      = kzalloc(req->length, gfp_flags);
836 	if (req->buf == NULL) {
837 		retval = -ENOMEM;
838 		goto err_free_req;
839 	}
840 
841 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
842 		/* Assume that device is bus powered for now. */
843 		*(u16 *)req->buf = ci->remote_wakeup << 1;
844 		retval = 0;
845 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
846 		   == USB_RECIP_ENDPOINT) {
847 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
848 			TX : RX;
849 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
850 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
851 	}
852 	/* else do nothing; reserved for future use */
853 
854 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
855 	if (retval)
856 		goto err_free_buf;
857 
858 	return 0;
859 
860  err_free_buf:
861 	kfree(req->buf);
862  err_free_req:
863 	spin_unlock(hwep->lock);
864 	usb_ep_free_request(&hwep->ep, req);
865 	spin_lock(hwep->lock);
866 	return retval;
867 }
868 
869 /**
870  * isr_setup_status_complete: setup_status request complete function
871  * @ep:  endpoint
872  * @req: request handled
873  *
874  * Caller must release lock. Put the port in test mode if test mode
875  * feature is selected.
876  */
877 static void
878 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
879 {
880 	struct ci_hdrc *ci = req->context;
881 	unsigned long flags;
882 
883 	if (ci->setaddr) {
884 		hw_usb_set_address(ci, ci->address);
885 		ci->setaddr = false;
886 	}
887 
888 	spin_lock_irqsave(&ci->lock, flags);
889 	if (ci->test_mode)
890 		hw_port_test_set(ci, ci->test_mode);
891 	spin_unlock_irqrestore(&ci->lock, flags);
892 }
893 
894 /**
895  * isr_setup_status_phase: queues the status phase of a setup transation
896  * @ci: ci struct
897  *
898  * This function returns an error code
899  */
900 static int isr_setup_status_phase(struct ci_hdrc *ci)
901 {
902 	int retval;
903 	struct ci_hw_ep *hwep;
904 
905 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
906 	ci->status->context = ci;
907 	ci->status->complete = isr_setup_status_complete;
908 
909 	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
910 
911 	return retval;
912 }
913 
914 /**
915  * isr_tr_complete_low: transaction complete low level handler
916  * @hwep: endpoint
917  *
918  * This function returns an error code
919  * Caller must hold lock
920  */
921 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
922 __releases(hwep->lock)
923 __acquires(hwep->lock)
924 {
925 	struct ci_hw_req *hwreq, *hwreqtemp;
926 	struct ci_hw_ep *hweptemp = hwep;
927 	int retval = 0;
928 
929 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
930 			queue) {
931 		retval = _hardware_dequeue(hwep, hwreq);
932 		if (retval < 0)
933 			break;
934 		list_del_init(&hwreq->queue);
935 		if (hwreq->req.complete != NULL) {
936 			spin_unlock(hwep->lock);
937 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
938 					hwreq->req.length)
939 				hweptemp = hwep->ci->ep0in;
940 			hwreq->req.complete(&hweptemp->ep, &hwreq->req);
941 			spin_lock(hwep->lock);
942 		}
943 	}
944 
945 	if (retval == -EBUSY)
946 		retval = 0;
947 
948 	return retval;
949 }
950 
951 /**
952  * isr_setup_packet_handler: setup packet handler
953  * @ci: UDC descriptor
954  *
955  * This function handles setup packet
956  */
957 static void isr_setup_packet_handler(struct ci_hdrc *ci)
958 __releases(ci->lock)
959 __acquires(ci->lock)
960 {
961 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
962 	struct usb_ctrlrequest req;
963 	int type, num, dir, err = -EINVAL;
964 	u8 tmode = 0;
965 
966 	/*
967 	 * Flush data and handshake transactions of previous
968 	 * setup packet.
969 	 */
970 	_ep_nuke(ci->ep0out);
971 	_ep_nuke(ci->ep0in);
972 
973 	/* read_setup_packet */
974 	do {
975 		hw_test_and_set_setup_guard(ci);
976 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
977 	} while (!hw_test_and_clear_setup_guard(ci));
978 
979 	type = req.bRequestType;
980 
981 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
982 
983 	switch (req.bRequest) {
984 	case USB_REQ_CLEAR_FEATURE:
985 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
986 				le16_to_cpu(req.wValue) ==
987 				USB_ENDPOINT_HALT) {
988 			if (req.wLength != 0)
989 				break;
990 			num  = le16_to_cpu(req.wIndex);
991 			dir = num & USB_ENDPOINT_DIR_MASK;
992 			num &= USB_ENDPOINT_NUMBER_MASK;
993 			if (dir) /* TX */
994 				num += ci->hw_ep_max / 2;
995 			if (!ci->ci_hw_ep[num].wedge) {
996 				spin_unlock(&ci->lock);
997 				err = usb_ep_clear_halt(
998 					&ci->ci_hw_ep[num].ep);
999 				spin_lock(&ci->lock);
1000 				if (err)
1001 					break;
1002 			}
1003 			err = isr_setup_status_phase(ci);
1004 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1005 				le16_to_cpu(req.wValue) ==
1006 				USB_DEVICE_REMOTE_WAKEUP) {
1007 			if (req.wLength != 0)
1008 				break;
1009 			ci->remote_wakeup = 0;
1010 			err = isr_setup_status_phase(ci);
1011 		} else {
1012 			goto delegate;
1013 		}
1014 		break;
1015 	case USB_REQ_GET_STATUS:
1016 		if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
1017 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1018 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1019 			goto delegate;
1020 		if (le16_to_cpu(req.wLength) != 2 ||
1021 		    le16_to_cpu(req.wValue)  != 0)
1022 			break;
1023 		err = isr_get_status_response(ci, &req);
1024 		break;
1025 	case USB_REQ_SET_ADDRESS:
1026 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1027 			goto delegate;
1028 		if (le16_to_cpu(req.wLength) != 0 ||
1029 		    le16_to_cpu(req.wIndex)  != 0)
1030 			break;
1031 		ci->address = (u8)le16_to_cpu(req.wValue);
1032 		ci->setaddr = true;
1033 		err = isr_setup_status_phase(ci);
1034 		break;
1035 	case USB_REQ_SET_FEATURE:
1036 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1037 				le16_to_cpu(req.wValue) ==
1038 				USB_ENDPOINT_HALT) {
1039 			if (req.wLength != 0)
1040 				break;
1041 			num  = le16_to_cpu(req.wIndex);
1042 			dir = num & USB_ENDPOINT_DIR_MASK;
1043 			num &= USB_ENDPOINT_NUMBER_MASK;
1044 			if (dir) /* TX */
1045 				num += ci->hw_ep_max / 2;
1046 
1047 			spin_unlock(&ci->lock);
1048 			err = usb_ep_set_halt(&ci->ci_hw_ep[num].ep);
1049 			spin_lock(&ci->lock);
1050 			if (!err)
1051 				isr_setup_status_phase(ci);
1052 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1053 			if (req.wLength != 0)
1054 				break;
1055 			switch (le16_to_cpu(req.wValue)) {
1056 			case USB_DEVICE_REMOTE_WAKEUP:
1057 				ci->remote_wakeup = 1;
1058 				err = isr_setup_status_phase(ci);
1059 				break;
1060 			case USB_DEVICE_TEST_MODE:
1061 				tmode = le16_to_cpu(req.wIndex) >> 8;
1062 				switch (tmode) {
1063 				case TEST_J:
1064 				case TEST_K:
1065 				case TEST_SE0_NAK:
1066 				case TEST_PACKET:
1067 				case TEST_FORCE_EN:
1068 					ci->test_mode = tmode;
1069 					err = isr_setup_status_phase(
1070 							ci);
1071 					break;
1072 				default:
1073 					break;
1074 				}
1075 			default:
1076 				goto delegate;
1077 			}
1078 		} else {
1079 			goto delegate;
1080 		}
1081 		break;
1082 	default:
1083 delegate:
1084 		if (req.wLength == 0)   /* no data phase */
1085 			ci->ep0_dir = TX;
1086 
1087 		spin_unlock(&ci->lock);
1088 		err = ci->driver->setup(&ci->gadget, &req);
1089 		spin_lock(&ci->lock);
1090 		break;
1091 	}
1092 
1093 	if (err < 0) {
1094 		spin_unlock(&ci->lock);
1095 		if (usb_ep_set_halt(&hwep->ep))
1096 			dev_err(ci->dev, "error: ep_set_halt\n");
1097 		spin_lock(&ci->lock);
1098 	}
1099 }
1100 
1101 /**
1102  * isr_tr_complete_handler: transaction complete interrupt handler
1103  * @ci: UDC descriptor
1104  *
1105  * This function handles traffic events
1106  */
1107 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1108 __releases(ci->lock)
1109 __acquires(ci->lock)
1110 {
1111 	unsigned i;
1112 	int err;
1113 
1114 	for (i = 0; i < ci->hw_ep_max; i++) {
1115 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1116 
1117 		if (hwep->ep.desc == NULL)
1118 			continue;   /* not configured */
1119 
1120 		if (hw_test_and_clear_complete(ci, i)) {
1121 			err = isr_tr_complete_low(hwep);
1122 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1123 				if (err > 0)   /* needs status phase */
1124 					err = isr_setup_status_phase(ci);
1125 				if (err < 0) {
1126 					spin_unlock(&ci->lock);
1127 					if (usb_ep_set_halt(&hwep->ep))
1128 						dev_err(ci->dev,
1129 							"error: ep_set_halt\n");
1130 					spin_lock(&ci->lock);
1131 				}
1132 			}
1133 		}
1134 
1135 		/* Only handle setup packet below */
1136 		if (i == 0 &&
1137 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1138 			isr_setup_packet_handler(ci);
1139 	}
1140 }
1141 
1142 /******************************************************************************
1143  * ENDPT block
1144  *****************************************************************************/
1145 /**
1146  * ep_enable: configure endpoint, making it usable
1147  *
1148  * Check usb_ep_enable() at "usb_gadget.h" for details
1149  */
1150 static int ep_enable(struct usb_ep *ep,
1151 		     const struct usb_endpoint_descriptor *desc)
1152 {
1153 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1154 	int retval = 0;
1155 	unsigned long flags;
1156 	u32 cap = 0;
1157 
1158 	if (ep == NULL || desc == NULL)
1159 		return -EINVAL;
1160 
1161 	spin_lock_irqsave(hwep->lock, flags);
1162 
1163 	/* only internal SW should enable ctrl endpts */
1164 
1165 	hwep->ep.desc = desc;
1166 
1167 	if (!list_empty(&hwep->qh.queue))
1168 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1169 
1170 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1171 	hwep->num  = usb_endpoint_num(desc);
1172 	hwep->type = usb_endpoint_type(desc);
1173 
1174 	hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1175 	hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1176 
1177 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1178 		cap |= QH_IOS;
1179 	if (hwep->num)
1180 		cap |= QH_ZLT;
1181 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1182 	/*
1183 	 * For ISO-TX, we set mult at QH as the largest value, and use
1184 	 * MultO at TD as real mult value.
1185 	 */
1186 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1187 		cap |= 3 << __ffs(QH_MULT);
1188 
1189 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1190 
1191 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1192 
1193 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1194 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1195 		retval = -EINVAL;
1196 	}
1197 
1198 	/*
1199 	 * Enable endpoints in the HW other than ep0 as ep0
1200 	 * is always enabled
1201 	 */
1202 	if (hwep->num)
1203 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1204 				       hwep->type);
1205 
1206 	spin_unlock_irqrestore(hwep->lock, flags);
1207 	return retval;
1208 }
1209 
1210 /**
1211  * ep_disable: endpoint is no longer usable
1212  *
1213  * Check usb_ep_disable() at "usb_gadget.h" for details
1214  */
1215 static int ep_disable(struct usb_ep *ep)
1216 {
1217 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1218 	int direction, retval = 0;
1219 	unsigned long flags;
1220 
1221 	if (ep == NULL)
1222 		return -EINVAL;
1223 	else if (hwep->ep.desc == NULL)
1224 		return -EBUSY;
1225 
1226 	spin_lock_irqsave(hwep->lock, flags);
1227 
1228 	/* only internal SW should disable ctrl endpts */
1229 
1230 	direction = hwep->dir;
1231 	do {
1232 		retval |= _ep_nuke(hwep);
1233 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1234 
1235 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1236 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1237 
1238 	} while (hwep->dir != direction);
1239 
1240 	hwep->ep.desc = NULL;
1241 
1242 	spin_unlock_irqrestore(hwep->lock, flags);
1243 	return retval;
1244 }
1245 
1246 /**
1247  * ep_alloc_request: allocate a request object to use with this endpoint
1248  *
1249  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1250  */
1251 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1252 {
1253 	struct ci_hw_req *hwreq = NULL;
1254 
1255 	if (ep == NULL)
1256 		return NULL;
1257 
1258 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1259 	if (hwreq != NULL) {
1260 		INIT_LIST_HEAD(&hwreq->queue);
1261 		INIT_LIST_HEAD(&hwreq->tds);
1262 	}
1263 
1264 	return (hwreq == NULL) ? NULL : &hwreq->req;
1265 }
1266 
1267 /**
1268  * ep_free_request: frees a request object
1269  *
1270  * Check usb_ep_free_request() at "usb_gadget.h" for details
1271  */
1272 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1273 {
1274 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1275 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1276 	struct td_node *node, *tmpnode;
1277 	unsigned long flags;
1278 
1279 	if (ep == NULL || req == NULL) {
1280 		return;
1281 	} else if (!list_empty(&hwreq->queue)) {
1282 		dev_err(hwep->ci->dev, "freeing queued request\n");
1283 		return;
1284 	}
1285 
1286 	spin_lock_irqsave(hwep->lock, flags);
1287 
1288 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1289 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1290 		list_del_init(&node->td);
1291 		node->ptr = NULL;
1292 		kfree(node);
1293 	}
1294 
1295 	kfree(hwreq);
1296 
1297 	spin_unlock_irqrestore(hwep->lock, flags);
1298 }
1299 
1300 /**
1301  * ep_queue: queues (submits) an I/O request to an endpoint
1302  *
1303  * Check usb_ep_queue()* at usb_gadget.h" for details
1304  */
1305 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1306 		    gfp_t __maybe_unused gfp_flags)
1307 {
1308 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1309 	int retval = 0;
1310 	unsigned long flags;
1311 
1312 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1313 		return -EINVAL;
1314 
1315 	spin_lock_irqsave(hwep->lock, flags);
1316 	retval = _ep_queue(ep, req, gfp_flags);
1317 	spin_unlock_irqrestore(hwep->lock, flags);
1318 	return retval;
1319 }
1320 
1321 /**
1322  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1323  *
1324  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1325  */
1326 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1327 {
1328 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1329 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1330 	unsigned long flags;
1331 
1332 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1333 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1334 		list_empty(&hwep->qh.queue))
1335 		return -EINVAL;
1336 
1337 	spin_lock_irqsave(hwep->lock, flags);
1338 
1339 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1340 
1341 	/* pop request */
1342 	list_del_init(&hwreq->queue);
1343 
1344 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1345 
1346 	req->status = -ECONNRESET;
1347 
1348 	if (hwreq->req.complete != NULL) {
1349 		spin_unlock(hwep->lock);
1350 		hwreq->req.complete(&hwep->ep, &hwreq->req);
1351 		spin_lock(hwep->lock);
1352 	}
1353 
1354 	spin_unlock_irqrestore(hwep->lock, flags);
1355 	return 0;
1356 }
1357 
1358 /**
1359  * ep_set_halt: sets the endpoint halt feature
1360  *
1361  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1362  */
1363 static int ep_set_halt(struct usb_ep *ep, int value)
1364 {
1365 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1366 	int direction, retval = 0;
1367 	unsigned long flags;
1368 
1369 	if (ep == NULL || hwep->ep.desc == NULL)
1370 		return -EINVAL;
1371 
1372 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
1373 		return -EOPNOTSUPP;
1374 
1375 	spin_lock_irqsave(hwep->lock, flags);
1376 
1377 #ifndef STALL_IN
1378 	/* g_file_storage MS compliant but g_zero fails chapter 9 compliance */
1379 	if (value && hwep->type == USB_ENDPOINT_XFER_BULK && hwep->dir == TX &&
1380 	    !list_empty(&hwep->qh.queue)) {
1381 		spin_unlock_irqrestore(hwep->lock, flags);
1382 		return -EAGAIN;
1383 	}
1384 #endif
1385 
1386 	direction = hwep->dir;
1387 	do {
1388 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
1389 
1390 		if (!value)
1391 			hwep->wedge = 0;
1392 
1393 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1394 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1395 
1396 	} while (hwep->dir != direction);
1397 
1398 	spin_unlock_irqrestore(hwep->lock, flags);
1399 	return retval;
1400 }
1401 
1402 /**
1403  * ep_set_wedge: sets the halt feature and ignores clear requests
1404  *
1405  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1406  */
1407 static int ep_set_wedge(struct usb_ep *ep)
1408 {
1409 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1410 	unsigned long flags;
1411 
1412 	if (ep == NULL || hwep->ep.desc == NULL)
1413 		return -EINVAL;
1414 
1415 	spin_lock_irqsave(hwep->lock, flags);
1416 	hwep->wedge = 1;
1417 	spin_unlock_irqrestore(hwep->lock, flags);
1418 
1419 	return usb_ep_set_halt(ep);
1420 }
1421 
1422 /**
1423  * ep_fifo_flush: flushes contents of a fifo
1424  *
1425  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1426  */
1427 static void ep_fifo_flush(struct usb_ep *ep)
1428 {
1429 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1430 	unsigned long flags;
1431 
1432 	if (ep == NULL) {
1433 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1434 		return;
1435 	}
1436 
1437 	spin_lock_irqsave(hwep->lock, flags);
1438 
1439 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1440 
1441 	spin_unlock_irqrestore(hwep->lock, flags);
1442 }
1443 
1444 /**
1445  * Endpoint-specific part of the API to the USB controller hardware
1446  * Check "usb_gadget.h" for details
1447  */
1448 static const struct usb_ep_ops usb_ep_ops = {
1449 	.enable	       = ep_enable,
1450 	.disable       = ep_disable,
1451 	.alloc_request = ep_alloc_request,
1452 	.free_request  = ep_free_request,
1453 	.queue	       = ep_queue,
1454 	.dequeue       = ep_dequeue,
1455 	.set_halt      = ep_set_halt,
1456 	.set_wedge     = ep_set_wedge,
1457 	.fifo_flush    = ep_fifo_flush,
1458 };
1459 
1460 /******************************************************************************
1461  * GADGET block
1462  *****************************************************************************/
1463 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1464 {
1465 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1466 	unsigned long flags;
1467 	int gadget_ready = 0;
1468 
1469 	spin_lock_irqsave(&ci->lock, flags);
1470 	ci->vbus_active = is_active;
1471 	if (ci->driver)
1472 		gadget_ready = 1;
1473 	spin_unlock_irqrestore(&ci->lock, flags);
1474 
1475 	if (gadget_ready) {
1476 		if (is_active) {
1477 			pm_runtime_get_sync(&_gadget->dev);
1478 			hw_device_reset(ci, USBMODE_CM_DC);
1479 			hw_device_state(ci, ci->ep0out->qh.dma);
1480 			dev_dbg(ci->dev, "Connected to host\n");
1481 		} else {
1482 			if (ci->driver)
1483 				ci->driver->disconnect(&ci->gadget);
1484 			hw_device_state(ci, 0);
1485 			if (ci->platdata->notify_event)
1486 				ci->platdata->notify_event(ci,
1487 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1488 			_gadget_stop_activity(&ci->gadget);
1489 			pm_runtime_put_sync(&_gadget->dev);
1490 			dev_dbg(ci->dev, "Disconnected from host\n");
1491 		}
1492 	}
1493 
1494 	return 0;
1495 }
1496 
1497 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1498 {
1499 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1500 	unsigned long flags;
1501 	int ret = 0;
1502 
1503 	spin_lock_irqsave(&ci->lock, flags);
1504 	if (!ci->remote_wakeup) {
1505 		ret = -EOPNOTSUPP;
1506 		goto out;
1507 	}
1508 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1509 		ret = -EINVAL;
1510 		goto out;
1511 	}
1512 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1513 out:
1514 	spin_unlock_irqrestore(&ci->lock, flags);
1515 	return ret;
1516 }
1517 
1518 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1519 {
1520 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1521 
1522 	if (ci->transceiver)
1523 		return usb_phy_set_power(ci->transceiver, ma);
1524 	return -ENOTSUPP;
1525 }
1526 
1527 /* Change Data+ pullup status
1528  * this func is used by usb_gadget_connect/disconnet
1529  */
1530 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1531 {
1532 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1533 
1534 	if (!ci->vbus_active)
1535 		return -EOPNOTSUPP;
1536 
1537 	if (is_on)
1538 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1539 	else
1540 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1541 
1542 	return 0;
1543 }
1544 
1545 static int ci_udc_start(struct usb_gadget *gadget,
1546 			 struct usb_gadget_driver *driver);
1547 static int ci_udc_stop(struct usb_gadget *gadget,
1548 			struct usb_gadget_driver *driver);
1549 /**
1550  * Device operations part of the API to the USB controller hardware,
1551  * which don't involve endpoints (or i/o)
1552  * Check  "usb_gadget.h" for details
1553  */
1554 static const struct usb_gadget_ops usb_gadget_ops = {
1555 	.vbus_session	= ci_udc_vbus_session,
1556 	.wakeup		= ci_udc_wakeup,
1557 	.pullup		= ci_udc_pullup,
1558 	.vbus_draw	= ci_udc_vbus_draw,
1559 	.udc_start	= ci_udc_start,
1560 	.udc_stop	= ci_udc_stop,
1561 };
1562 
1563 static int init_eps(struct ci_hdrc *ci)
1564 {
1565 	int retval = 0, i, j;
1566 
1567 	for (i = 0; i < ci->hw_ep_max/2; i++)
1568 		for (j = RX; j <= TX; j++) {
1569 			int k = i + j * ci->hw_ep_max/2;
1570 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1571 
1572 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1573 					(j == TX)  ? "in" : "out");
1574 
1575 			hwep->ci          = ci;
1576 			hwep->lock         = &ci->lock;
1577 			hwep->td_pool      = ci->td_pool;
1578 
1579 			hwep->ep.name      = hwep->name;
1580 			hwep->ep.ops       = &usb_ep_ops;
1581 			/*
1582 			 * for ep0: maxP defined in desc, for other
1583 			 * eps, maxP is set by epautoconfig() called
1584 			 * by gadget layer
1585 			 */
1586 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1587 
1588 			INIT_LIST_HEAD(&hwep->qh.queue);
1589 			hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1590 						     &hwep->qh.dma);
1591 			if (hwep->qh.ptr == NULL)
1592 				retval = -ENOMEM;
1593 			else
1594 				memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1595 
1596 			/*
1597 			 * set up shorthands for ep0 out and in endpoints,
1598 			 * don't add to gadget's ep_list
1599 			 */
1600 			if (i == 0) {
1601 				if (j == RX)
1602 					ci->ep0out = hwep;
1603 				else
1604 					ci->ep0in = hwep;
1605 
1606 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1607 				continue;
1608 			}
1609 
1610 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1611 		}
1612 
1613 	return retval;
1614 }
1615 
1616 static void destroy_eps(struct ci_hdrc *ci)
1617 {
1618 	int i;
1619 
1620 	for (i = 0; i < ci->hw_ep_max; i++) {
1621 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1622 
1623 		if (hwep->pending_td)
1624 			free_pending_td(hwep);
1625 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1626 	}
1627 }
1628 
1629 /**
1630  * ci_udc_start: register a gadget driver
1631  * @gadget: our gadget
1632  * @driver: the driver being registered
1633  *
1634  * Interrupts are enabled here.
1635  */
1636 static int ci_udc_start(struct usb_gadget *gadget,
1637 			 struct usb_gadget_driver *driver)
1638 {
1639 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1640 	unsigned long flags;
1641 	int retval = -ENOMEM;
1642 
1643 	if (driver->disconnect == NULL)
1644 		return -EINVAL;
1645 
1646 
1647 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1648 	retval = usb_ep_enable(&ci->ep0out->ep);
1649 	if (retval)
1650 		return retval;
1651 
1652 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1653 	retval = usb_ep_enable(&ci->ep0in->ep);
1654 	if (retval)
1655 		return retval;
1656 
1657 	ci->driver = driver;
1658 	pm_runtime_get_sync(&ci->gadget.dev);
1659 	if (ci->vbus_active) {
1660 		spin_lock_irqsave(&ci->lock, flags);
1661 		hw_device_reset(ci, USBMODE_CM_DC);
1662 	} else {
1663 		pm_runtime_put_sync(&ci->gadget.dev);
1664 		return retval;
1665 	}
1666 
1667 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1668 	spin_unlock_irqrestore(&ci->lock, flags);
1669 	if (retval)
1670 		pm_runtime_put_sync(&ci->gadget.dev);
1671 
1672 	return retval;
1673 }
1674 
1675 /**
1676  * ci_udc_stop: unregister a gadget driver
1677  */
1678 static int ci_udc_stop(struct usb_gadget *gadget,
1679 			struct usb_gadget_driver *driver)
1680 {
1681 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1682 	unsigned long flags;
1683 
1684 	spin_lock_irqsave(&ci->lock, flags);
1685 
1686 	if (ci->vbus_active) {
1687 		hw_device_state(ci, 0);
1688 		if (ci->platdata->notify_event)
1689 			ci->platdata->notify_event(ci,
1690 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1691 		spin_unlock_irqrestore(&ci->lock, flags);
1692 		_gadget_stop_activity(&ci->gadget);
1693 		spin_lock_irqsave(&ci->lock, flags);
1694 		pm_runtime_put(&ci->gadget.dev);
1695 	}
1696 
1697 	ci->driver = NULL;
1698 	spin_unlock_irqrestore(&ci->lock, flags);
1699 
1700 	return 0;
1701 }
1702 
1703 /******************************************************************************
1704  * BUS block
1705  *****************************************************************************/
1706 /**
1707  * udc_irq: ci interrupt handler
1708  *
1709  * This function returns IRQ_HANDLED if the IRQ has been handled
1710  * It locks access to registers
1711  */
1712 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1713 {
1714 	irqreturn_t retval;
1715 	u32 intr;
1716 
1717 	if (ci == NULL)
1718 		return IRQ_HANDLED;
1719 
1720 	spin_lock(&ci->lock);
1721 
1722 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1723 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1724 				USBMODE_CM_DC) {
1725 			spin_unlock(&ci->lock);
1726 			return IRQ_NONE;
1727 		}
1728 	}
1729 	intr = hw_test_and_clear_intr_active(ci);
1730 
1731 	if (intr) {
1732 		/* order defines priority - do NOT change it */
1733 		if (USBi_URI & intr)
1734 			isr_reset_handler(ci);
1735 
1736 		if (USBi_PCI & intr) {
1737 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1738 				USB_SPEED_HIGH : USB_SPEED_FULL;
1739 			if (ci->suspended && ci->driver->resume) {
1740 				spin_unlock(&ci->lock);
1741 				ci->driver->resume(&ci->gadget);
1742 				spin_lock(&ci->lock);
1743 				ci->suspended = 0;
1744 			}
1745 		}
1746 
1747 		if (USBi_UI  & intr)
1748 			isr_tr_complete_handler(ci);
1749 
1750 		if (USBi_SLI & intr) {
1751 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1752 			    ci->driver->suspend) {
1753 				ci->suspended = 1;
1754 				spin_unlock(&ci->lock);
1755 				ci->driver->suspend(&ci->gadget);
1756 				spin_lock(&ci->lock);
1757 			}
1758 		}
1759 		retval = IRQ_HANDLED;
1760 	} else {
1761 		retval = IRQ_NONE;
1762 	}
1763 	spin_unlock(&ci->lock);
1764 
1765 	return retval;
1766 }
1767 
1768 /**
1769  * udc_start: initialize gadget role
1770  * @ci: chipidea controller
1771  */
1772 static int udc_start(struct ci_hdrc *ci)
1773 {
1774 	struct device *dev = ci->dev;
1775 	int retval = 0;
1776 
1777 	spin_lock_init(&ci->lock);
1778 
1779 	ci->gadget.ops          = &usb_gadget_ops;
1780 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1781 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1782 	ci->gadget.is_otg       = 0;
1783 	ci->gadget.name         = ci->platdata->name;
1784 
1785 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1786 
1787 	/* alloc resources */
1788 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1789 				       sizeof(struct ci_hw_qh),
1790 				       64, CI_HDRC_PAGE_SIZE);
1791 	if (ci->qh_pool == NULL)
1792 		return -ENOMEM;
1793 
1794 	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1795 				       sizeof(struct ci_hw_td),
1796 				       64, CI_HDRC_PAGE_SIZE);
1797 	if (ci->td_pool == NULL) {
1798 		retval = -ENOMEM;
1799 		goto free_qh_pool;
1800 	}
1801 
1802 	retval = init_eps(ci);
1803 	if (retval)
1804 		goto free_pools;
1805 
1806 	ci->gadget.ep0 = &ci->ep0in->ep;
1807 
1808 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1809 	if (retval)
1810 		goto destroy_eps;
1811 
1812 	pm_runtime_no_callbacks(&ci->gadget.dev);
1813 	pm_runtime_enable(&ci->gadget.dev);
1814 
1815 	return retval;
1816 
1817 destroy_eps:
1818 	destroy_eps(ci);
1819 free_pools:
1820 	dma_pool_destroy(ci->td_pool);
1821 free_qh_pool:
1822 	dma_pool_destroy(ci->qh_pool);
1823 	return retval;
1824 }
1825 
1826 /**
1827  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1828  *
1829  * No interrupts active, the IRQ has been released
1830  */
1831 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1832 {
1833 	if (!ci->roles[CI_ROLE_GADGET])
1834 		return;
1835 
1836 	usb_del_gadget_udc(&ci->gadget);
1837 
1838 	destroy_eps(ci);
1839 
1840 	dma_pool_destroy(ci->td_pool);
1841 	dma_pool_destroy(ci->qh_pool);
1842 }
1843 
1844 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1845 {
1846 	if (ci->is_otg) {
1847 		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
1848 		ci_enable_otg_interrupt(ci, OTGSC_BSVIE);
1849 	}
1850 
1851 	return 0;
1852 }
1853 
1854 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1855 {
1856 	if (ci->is_otg) {
1857 		/* host doesn't care B_SESSION_VALID event */
1858 		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
1859 		ci_disable_otg_interrupt(ci, OTGSC_BSVIE);
1860 	}
1861 }
1862 
1863 /**
1864  * ci_hdrc_gadget_init - initialize device related bits
1865  * ci: the controller
1866  *
1867  * This function initializes the gadget, if the device is "device capable".
1868  */
1869 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1870 {
1871 	struct ci_role_driver *rdrv;
1872 
1873 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1874 		return -ENXIO;
1875 
1876 	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1877 	if (!rdrv)
1878 		return -ENOMEM;
1879 
1880 	rdrv->start	= udc_id_switch_for_device;
1881 	rdrv->stop	= udc_id_switch_for_host;
1882 	rdrv->irq	= udc_irq;
1883 	rdrv->name	= "gadget";
1884 	ci->roles[CI_ROLE_GADGET] = rdrv;
1885 
1886 	return udc_start(ci);
1887 }
1888