xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision 8a10bc9d)
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, BIT(n), 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_test_and_clear_setup_status: test & clear setup status (execute without
182  *                                 interruption)
183  * @n: endpoint number
184  *
185  * This function returns setup status
186  */
187 static int hw_test_and_clear_setup_status(struct ci_hdrc *ci, int n)
188 {
189 	n = ep_to_bit(ci, n);
190 	return hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(n));
191 }
192 
193 /**
194  * hw_ep_prime: primes endpoint (execute without interruption)
195  * @num:     endpoint number
196  * @dir:     endpoint direction
197  * @is_ctrl: true if control endpoint
198  *
199  * This function returns an error code
200  */
201 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
202 {
203 	int n = hw_ep_bit(num, dir);
204 
205 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
206 		return -EAGAIN;
207 
208 	hw_write(ci, OP_ENDPTPRIME, BIT(n), BIT(n));
209 
210 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
211 		cpu_relax();
212 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
213 		return -EAGAIN;
214 
215 	/* status shoult be tested according with manual but it doesn't work */
216 	return 0;
217 }
218 
219 /**
220  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
221  *                 without interruption)
222  * @num:   endpoint number
223  * @dir:   endpoint direction
224  * @value: true => stall, false => unstall
225  *
226  * This function returns an error code
227  */
228 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
229 {
230 	if (value != 0 && value != 1)
231 		return -EINVAL;
232 
233 	do {
234 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
235 		u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
236 		u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
237 
238 		/* data toggle - reserved for EP0 but it's in ESS */
239 		hw_write(ci, reg, mask_xs|mask_xr,
240 			  value ? mask_xs : mask_xr);
241 	} while (value != hw_ep_get_halt(ci, num, dir));
242 
243 	return 0;
244 }
245 
246 /**
247  * hw_is_port_high_speed: test if port is high speed
248  *
249  * This function returns true if high speed port
250  */
251 static int hw_port_is_high_speed(struct ci_hdrc *ci)
252 {
253 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
254 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
255 }
256 
257 /**
258  * hw_read_intr_enable: returns interrupt enable register
259  *
260  * This function returns register data
261  */
262 static u32 hw_read_intr_enable(struct ci_hdrc *ci)
263 {
264 	return hw_read(ci, OP_USBINTR, ~0);
265 }
266 
267 /**
268  * hw_read_intr_status: returns interrupt status register
269  *
270  * This function returns register data
271  */
272 static u32 hw_read_intr_status(struct ci_hdrc *ci)
273 {
274 	return hw_read(ci, OP_USBSTS, ~0);
275 }
276 
277 /**
278  * hw_test_and_clear_complete: test & clear complete status (execute without
279  *                             interruption)
280  * @n: endpoint number
281  *
282  * This function returns complete status
283  */
284 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
285 {
286 	n = ep_to_bit(ci, n);
287 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
288 }
289 
290 /**
291  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
292  *                                without interruption)
293  *
294  * This function returns active interrutps
295  */
296 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
297 {
298 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
299 
300 	hw_write(ci, OP_USBSTS, ~0, reg);
301 	return reg;
302 }
303 
304 /**
305  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
306  *                                interruption)
307  *
308  * This function returns guard value
309  */
310 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
311 {
312 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
313 }
314 
315 /**
316  * hw_test_and_set_setup_guard: test & set setup guard (execute without
317  *                              interruption)
318  *
319  * This function returns guard value
320  */
321 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
322 {
323 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
324 }
325 
326 /**
327  * hw_usb_set_address: configures USB address (execute without interruption)
328  * @value: new USB address
329  *
330  * This function explicitly sets the address, without the "USBADRA" (advance)
331  * feature, which is not supported by older versions of the controller.
332  */
333 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
334 {
335 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
336 		 value << __ffs(DEVICEADDR_USBADR));
337 }
338 
339 /**
340  * hw_usb_reset: restart device after a bus reset (execute without
341  *               interruption)
342  *
343  * This function returns an error code
344  */
345 static int hw_usb_reset(struct ci_hdrc *ci)
346 {
347 	hw_usb_set_address(ci, 0);
348 
349 	/* ESS flushes only at end?!? */
350 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
351 
352 	/* clear setup token semaphores */
353 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
354 
355 	/* clear complete status */
356 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
357 
358 	/* wait until all bits cleared */
359 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
360 		udelay(10);             /* not RTOS friendly */
361 
362 	/* reset all endpoints ? */
363 
364 	/* reset internal status and wait for further instructions
365 	   no need to verify the port reset status (ESS does it) */
366 
367 	return 0;
368 }
369 
370 /******************************************************************************
371  * UTIL block
372  *****************************************************************************/
373 
374 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
375 			  unsigned length)
376 {
377 	int i;
378 	u32 temp;
379 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
380 						  GFP_ATOMIC);
381 
382 	if (node == NULL)
383 		return -ENOMEM;
384 
385 	node->ptr = dma_pool_alloc(hwep->td_pool, GFP_ATOMIC,
386 				   &node->dma);
387 	if (node->ptr == NULL) {
388 		kfree(node);
389 		return -ENOMEM;
390 	}
391 
392 	memset(node->ptr, 0, sizeof(struct ci_hw_td));
393 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
394 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
395 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
396 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
397 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
398 
399 		if (hwreq->req.length == 0
400 				|| hwreq->req.length % hwep->ep.maxpacket)
401 			mul++;
402 		node->ptr->token |= mul << __ffs(TD_MULTO);
403 	}
404 
405 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
406 	if (length) {
407 		node->ptr->page[0] = cpu_to_le32(temp);
408 		for (i = 1; i < TD_PAGE_COUNT; i++) {
409 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
410 			page &= ~TD_RESERVED_MASK;
411 			node->ptr->page[i] = cpu_to_le32(page);
412 		}
413 	}
414 
415 	hwreq->req.actual += length;
416 
417 	if (!list_empty(&hwreq->tds)) {
418 		/* get the last entry */
419 		lastnode = list_entry(hwreq->tds.prev,
420 				struct td_node, td);
421 		lastnode->ptr->next = cpu_to_le32(node->dma);
422 	}
423 
424 	INIT_LIST_HEAD(&node->td);
425 	list_add_tail(&node->td, &hwreq->tds);
426 
427 	return 0;
428 }
429 
430 /**
431  * _usb_addr: calculates endpoint address from direction & number
432  * @ep:  endpoint
433  */
434 static inline u8 _usb_addr(struct ci_hw_ep *ep)
435 {
436 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
437 }
438 
439 /**
440  * _hardware_queue: configures a request at hardware level
441  * @gadget: gadget
442  * @hwep:   endpoint
443  *
444  * This function returns an error code
445  */
446 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
447 {
448 	struct ci_hdrc *ci = hwep->ci;
449 	int ret = 0;
450 	unsigned rest = hwreq->req.length;
451 	int pages = TD_PAGE_COUNT;
452 	struct td_node *firstnode, *lastnode;
453 
454 	/* don't queue twice */
455 	if (hwreq->req.status == -EALREADY)
456 		return -EALREADY;
457 
458 	hwreq->req.status = -EALREADY;
459 
460 	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
461 	if (ret)
462 		return ret;
463 
464 	/*
465 	 * The first buffer could be not page aligned.
466 	 * In that case we have to span into one extra td.
467 	 */
468 	if (hwreq->req.dma % PAGE_SIZE)
469 		pages--;
470 
471 	if (rest == 0)
472 		add_td_to_list(hwep, hwreq, 0);
473 
474 	while (rest > 0) {
475 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
476 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
477 		add_td_to_list(hwep, hwreq, count);
478 		rest -= count;
479 	}
480 
481 	if (hwreq->req.zero && hwreq->req.length
482 	    && (hwreq->req.length % hwep->ep.maxpacket == 0))
483 		add_td_to_list(hwep, hwreq, 0);
484 
485 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
486 
487 	lastnode = list_entry(hwreq->tds.prev,
488 		struct td_node, td);
489 
490 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
491 	if (!hwreq->req.no_interrupt)
492 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
493 	wmb();
494 
495 	hwreq->req.actual = 0;
496 	if (!list_empty(&hwep->qh.queue)) {
497 		struct ci_hw_req *hwreqprev;
498 		int n = hw_ep_bit(hwep->num, hwep->dir);
499 		int tmp_stat;
500 		struct td_node *prevlastnode;
501 		u32 next = firstnode->dma & TD_ADDR_MASK;
502 
503 		hwreqprev = list_entry(hwep->qh.queue.prev,
504 				struct ci_hw_req, queue);
505 		prevlastnode = list_entry(hwreqprev->tds.prev,
506 				struct td_node, td);
507 
508 		prevlastnode->ptr->next = cpu_to_le32(next);
509 		wmb();
510 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
511 			goto done;
512 		do {
513 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
514 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
515 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
516 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
517 		if (tmp_stat)
518 			goto done;
519 	}
520 
521 	/*  QH configuration */
522 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
523 	hwep->qh.ptr->td.token &=
524 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
525 
526 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
527 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
528 
529 		if (hwreq->req.length == 0
530 				|| hwreq->req.length % hwep->ep.maxpacket)
531 			mul++;
532 		hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
533 	}
534 
535 	wmb();   /* synchronize before ep prime */
536 
537 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
538 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
539 done:
540 	return ret;
541 }
542 
543 /*
544  * free_pending_td: remove a pending request for the endpoint
545  * @hwep: endpoint
546  */
547 static void free_pending_td(struct ci_hw_ep *hwep)
548 {
549 	struct td_node *pending = hwep->pending_td;
550 
551 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
552 	hwep->pending_td = NULL;
553 	kfree(pending);
554 }
555 
556 /**
557  * _hardware_dequeue: handles a request at hardware level
558  * @gadget: gadget
559  * @hwep:   endpoint
560  *
561  * This function returns an error code
562  */
563 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
564 {
565 	u32 tmptoken;
566 	struct td_node *node, *tmpnode;
567 	unsigned remaining_length;
568 	unsigned actual = hwreq->req.length;
569 
570 	if (hwreq->req.status != -EALREADY)
571 		return -EINVAL;
572 
573 	hwreq->req.status = 0;
574 
575 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
576 		tmptoken = le32_to_cpu(node->ptr->token);
577 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
578 			hwreq->req.status = -EALREADY;
579 			return -EBUSY;
580 		}
581 
582 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
583 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
584 		actual -= remaining_length;
585 
586 		hwreq->req.status = tmptoken & TD_STATUS;
587 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
588 			hwreq->req.status = -EPIPE;
589 			break;
590 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
591 			hwreq->req.status = -EPROTO;
592 			break;
593 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
594 			hwreq->req.status = -EILSEQ;
595 			break;
596 		}
597 
598 		if (remaining_length) {
599 			if (hwep->dir) {
600 				hwreq->req.status = -EPROTO;
601 				break;
602 			}
603 		}
604 		/*
605 		 * As the hardware could still address the freed td
606 		 * which will run the udc unusable, the cleanup of the
607 		 * td has to be delayed by one.
608 		 */
609 		if (hwep->pending_td)
610 			free_pending_td(hwep);
611 
612 		hwep->pending_td = node;
613 		list_del_init(&node->td);
614 	}
615 
616 	usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
617 
618 	hwreq->req.actual += actual;
619 
620 	if (hwreq->req.status)
621 		return hwreq->req.status;
622 
623 	return hwreq->req.actual;
624 }
625 
626 /**
627  * _ep_nuke: dequeues all endpoint requests
628  * @hwep: endpoint
629  *
630  * This function returns an error code
631  * Caller must hold lock
632  */
633 static int _ep_nuke(struct ci_hw_ep *hwep)
634 __releases(hwep->lock)
635 __acquires(hwep->lock)
636 {
637 	struct td_node *node, *tmpnode;
638 	if (hwep == NULL)
639 		return -EINVAL;
640 
641 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
642 
643 	while (!list_empty(&hwep->qh.queue)) {
644 
645 		/* pop oldest request */
646 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
647 						     struct ci_hw_req, queue);
648 
649 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
650 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
651 			list_del_init(&node->td);
652 			node->ptr = NULL;
653 			kfree(node);
654 		}
655 
656 		list_del_init(&hwreq->queue);
657 		hwreq->req.status = -ESHUTDOWN;
658 
659 		if (hwreq->req.complete != NULL) {
660 			spin_unlock(hwep->lock);
661 			hwreq->req.complete(&hwep->ep, &hwreq->req);
662 			spin_lock(hwep->lock);
663 		}
664 	}
665 
666 	if (hwep->pending_td)
667 		free_pending_td(hwep);
668 
669 	return 0;
670 }
671 
672 /**
673  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
674  * @gadget: gadget
675  *
676  * This function returns an error code
677  */
678 static int _gadget_stop_activity(struct usb_gadget *gadget)
679 {
680 	struct usb_ep *ep;
681 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
682 	unsigned long flags;
683 
684 	spin_lock_irqsave(&ci->lock, flags);
685 	ci->gadget.speed = USB_SPEED_UNKNOWN;
686 	ci->remote_wakeup = 0;
687 	ci->suspended = 0;
688 	spin_unlock_irqrestore(&ci->lock, flags);
689 
690 	/* flush all endpoints */
691 	gadget_for_each_ep(ep, gadget) {
692 		usb_ep_fifo_flush(ep);
693 	}
694 	usb_ep_fifo_flush(&ci->ep0out->ep);
695 	usb_ep_fifo_flush(&ci->ep0in->ep);
696 
697 	/* make sure to disable all endpoints */
698 	gadget_for_each_ep(ep, gadget) {
699 		usb_ep_disable(ep);
700 	}
701 
702 	if (ci->status != NULL) {
703 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
704 		ci->status = NULL;
705 	}
706 
707 	return 0;
708 }
709 
710 /******************************************************************************
711  * ISR block
712  *****************************************************************************/
713 /**
714  * isr_reset_handler: USB reset interrupt handler
715  * @ci: UDC device
716  *
717  * This function resets USB engine after a bus reset occurred
718  */
719 static void isr_reset_handler(struct ci_hdrc *ci)
720 __releases(ci->lock)
721 __acquires(ci->lock)
722 {
723 	int retval;
724 
725 	spin_unlock(&ci->lock);
726 	if (ci->gadget.speed != USB_SPEED_UNKNOWN) {
727 		if (ci->driver)
728 			ci->driver->disconnect(&ci->gadget);
729 	}
730 
731 	retval = _gadget_stop_activity(&ci->gadget);
732 	if (retval)
733 		goto done;
734 
735 	retval = hw_usb_reset(ci);
736 	if (retval)
737 		goto done;
738 
739 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
740 	if (ci->status == NULL)
741 		retval = -ENOMEM;
742 
743 done:
744 	spin_lock(&ci->lock);
745 
746 	if (retval)
747 		dev_err(ci->dev, "error: %i\n", retval);
748 }
749 
750 /**
751  * isr_get_status_complete: get_status request complete function
752  * @ep:  endpoint
753  * @req: request handled
754  *
755  * Caller must release lock
756  */
757 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
758 {
759 	if (ep == NULL || req == NULL)
760 		return;
761 
762 	kfree(req->buf);
763 	usb_ep_free_request(ep, req);
764 }
765 
766 /**
767  * _ep_queue: queues (submits) an I/O request to an endpoint
768  *
769  * Caller must hold lock
770  */
771 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
772 		    gfp_t __maybe_unused gfp_flags)
773 {
774 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
775 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
776 	struct ci_hdrc *ci = hwep->ci;
777 	int retval = 0;
778 
779 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
780 		return -EINVAL;
781 
782 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
783 		if (req->length)
784 			hwep = (ci->ep0_dir == RX) ?
785 			       ci->ep0out : ci->ep0in;
786 		if (!list_empty(&hwep->qh.queue)) {
787 			_ep_nuke(hwep);
788 			retval = -EOVERFLOW;
789 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
790 				 _usb_addr(hwep));
791 		}
792 	}
793 
794 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
795 	    hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
796 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
797 		return -EMSGSIZE;
798 	}
799 
800 	/* first nuke then test link, e.g. previous status has not sent */
801 	if (!list_empty(&hwreq->queue)) {
802 		dev_err(hwep->ci->dev, "request already in queue\n");
803 		return -EBUSY;
804 	}
805 
806 	/* push request */
807 	hwreq->req.status = -EINPROGRESS;
808 	hwreq->req.actual = 0;
809 
810 	retval = _hardware_enqueue(hwep, hwreq);
811 
812 	if (retval == -EALREADY)
813 		retval = 0;
814 	if (!retval)
815 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
816 
817 	return retval;
818 }
819 
820 /**
821  * isr_get_status_response: get_status request response
822  * @ci: ci struct
823  * @setup: setup request packet
824  *
825  * This function returns an error code
826  */
827 static int isr_get_status_response(struct ci_hdrc *ci,
828 				   struct usb_ctrlrequest *setup)
829 __releases(hwep->lock)
830 __acquires(hwep->lock)
831 {
832 	struct ci_hw_ep *hwep = ci->ep0in;
833 	struct usb_request *req = NULL;
834 	gfp_t gfp_flags = GFP_ATOMIC;
835 	int dir, num, retval;
836 
837 	if (hwep == NULL || setup == NULL)
838 		return -EINVAL;
839 
840 	spin_unlock(hwep->lock);
841 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
842 	spin_lock(hwep->lock);
843 	if (req == NULL)
844 		return -ENOMEM;
845 
846 	req->complete = isr_get_status_complete;
847 	req->length   = 2;
848 	req->buf      = kzalloc(req->length, gfp_flags);
849 	if (req->buf == NULL) {
850 		retval = -ENOMEM;
851 		goto err_free_req;
852 	}
853 
854 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
855 		/* Assume that device is bus powered for now. */
856 		*(u16 *)req->buf = ci->remote_wakeup << 1;
857 		retval = 0;
858 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
859 		   == USB_RECIP_ENDPOINT) {
860 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
861 			TX : RX;
862 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
863 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
864 	}
865 	/* else do nothing; reserved for future use */
866 
867 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
868 	if (retval)
869 		goto err_free_buf;
870 
871 	return 0;
872 
873  err_free_buf:
874 	kfree(req->buf);
875  err_free_req:
876 	spin_unlock(hwep->lock);
877 	usb_ep_free_request(&hwep->ep, req);
878 	spin_lock(hwep->lock);
879 	return retval;
880 }
881 
882 /**
883  * isr_setup_status_complete: setup_status request complete function
884  * @ep:  endpoint
885  * @req: request handled
886  *
887  * Caller must release lock. Put the port in test mode if test mode
888  * feature is selected.
889  */
890 static void
891 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
892 {
893 	struct ci_hdrc *ci = req->context;
894 	unsigned long flags;
895 
896 	if (ci->setaddr) {
897 		hw_usb_set_address(ci, ci->address);
898 		ci->setaddr = false;
899 	}
900 
901 	spin_lock_irqsave(&ci->lock, flags);
902 	if (ci->test_mode)
903 		hw_port_test_set(ci, ci->test_mode);
904 	spin_unlock_irqrestore(&ci->lock, flags);
905 }
906 
907 /**
908  * isr_setup_status_phase: queues the status phase of a setup transation
909  * @ci: ci struct
910  *
911  * This function returns an error code
912  */
913 static int isr_setup_status_phase(struct ci_hdrc *ci)
914 {
915 	int retval;
916 	struct ci_hw_ep *hwep;
917 
918 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
919 	ci->status->context = ci;
920 	ci->status->complete = isr_setup_status_complete;
921 
922 	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
923 
924 	return retval;
925 }
926 
927 /**
928  * isr_tr_complete_low: transaction complete low level handler
929  * @hwep: endpoint
930  *
931  * This function returns an error code
932  * Caller must hold lock
933  */
934 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
935 __releases(hwep->lock)
936 __acquires(hwep->lock)
937 {
938 	struct ci_hw_req *hwreq, *hwreqtemp;
939 	struct ci_hw_ep *hweptemp = hwep;
940 	int retval = 0;
941 
942 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
943 			queue) {
944 		retval = _hardware_dequeue(hwep, hwreq);
945 		if (retval < 0)
946 			break;
947 		list_del_init(&hwreq->queue);
948 		if (hwreq->req.complete != NULL) {
949 			spin_unlock(hwep->lock);
950 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
951 					hwreq->req.length)
952 				hweptemp = hwep->ci->ep0in;
953 			hwreq->req.complete(&hweptemp->ep, &hwreq->req);
954 			spin_lock(hwep->lock);
955 		}
956 	}
957 
958 	if (retval == -EBUSY)
959 		retval = 0;
960 
961 	return retval;
962 }
963 
964 /**
965  * isr_tr_complete_handler: transaction complete interrupt handler
966  * @ci: UDC descriptor
967  *
968  * This function handles traffic events
969  */
970 static void isr_tr_complete_handler(struct ci_hdrc *ci)
971 __releases(ci->lock)
972 __acquires(ci->lock)
973 {
974 	unsigned i;
975 	u8 tmode = 0;
976 
977 	for (i = 0; i < ci->hw_ep_max; i++) {
978 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
979 		int type, num, dir, err = -EINVAL;
980 		struct usb_ctrlrequest req;
981 
982 		if (hwep->ep.desc == NULL)
983 			continue;   /* not configured */
984 
985 		if (hw_test_and_clear_complete(ci, i)) {
986 			err = isr_tr_complete_low(hwep);
987 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
988 				if (err > 0)   /* needs status phase */
989 					err = isr_setup_status_phase(ci);
990 				if (err < 0) {
991 					spin_unlock(&ci->lock);
992 					if (usb_ep_set_halt(&hwep->ep))
993 						dev_err(ci->dev,
994 							"error: ep_set_halt\n");
995 					spin_lock(&ci->lock);
996 				}
997 			}
998 		}
999 
1000 		if (hwep->type != USB_ENDPOINT_XFER_CONTROL ||
1001 		    !hw_test_and_clear_setup_status(ci, i))
1002 			continue;
1003 
1004 		if (i != 0) {
1005 			dev_warn(ci->dev, "ctrl traffic at endpoint %d\n", i);
1006 			continue;
1007 		}
1008 
1009 		/*
1010 		 * Flush data and handshake transactions of previous
1011 		 * setup packet.
1012 		 */
1013 		_ep_nuke(ci->ep0out);
1014 		_ep_nuke(ci->ep0in);
1015 
1016 		/* read_setup_packet */
1017 		do {
1018 			hw_test_and_set_setup_guard(ci);
1019 			memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1020 		} while (!hw_test_and_clear_setup_guard(ci));
1021 
1022 		type = req.bRequestType;
1023 
1024 		ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1025 
1026 		switch (req.bRequest) {
1027 		case USB_REQ_CLEAR_FEATURE:
1028 			if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1029 					le16_to_cpu(req.wValue) ==
1030 					USB_ENDPOINT_HALT) {
1031 				if (req.wLength != 0)
1032 					break;
1033 				num  = le16_to_cpu(req.wIndex);
1034 				dir = num & USB_ENDPOINT_DIR_MASK;
1035 				num &= USB_ENDPOINT_NUMBER_MASK;
1036 				if (dir) /* TX */
1037 					num += ci->hw_ep_max/2;
1038 				if (!ci->ci_hw_ep[num].wedge) {
1039 					spin_unlock(&ci->lock);
1040 					err = usb_ep_clear_halt(
1041 						&ci->ci_hw_ep[num].ep);
1042 					spin_lock(&ci->lock);
1043 					if (err)
1044 						break;
1045 				}
1046 				err = isr_setup_status_phase(ci);
1047 			} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1048 					le16_to_cpu(req.wValue) ==
1049 					USB_DEVICE_REMOTE_WAKEUP) {
1050 				if (req.wLength != 0)
1051 					break;
1052 				ci->remote_wakeup = 0;
1053 				err = isr_setup_status_phase(ci);
1054 			} else {
1055 				goto delegate;
1056 			}
1057 			break;
1058 		case USB_REQ_GET_STATUS:
1059 			if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
1060 			    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1061 			    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1062 				goto delegate;
1063 			if (le16_to_cpu(req.wLength) != 2 ||
1064 			    le16_to_cpu(req.wValue)  != 0)
1065 				break;
1066 			err = isr_get_status_response(ci, &req);
1067 			break;
1068 		case USB_REQ_SET_ADDRESS:
1069 			if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1070 				goto delegate;
1071 			if (le16_to_cpu(req.wLength) != 0 ||
1072 			    le16_to_cpu(req.wIndex)  != 0)
1073 				break;
1074 			ci->address = (u8)le16_to_cpu(req.wValue);
1075 			ci->setaddr = true;
1076 			err = isr_setup_status_phase(ci);
1077 			break;
1078 		case USB_REQ_SET_FEATURE:
1079 			if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1080 					le16_to_cpu(req.wValue) ==
1081 					USB_ENDPOINT_HALT) {
1082 				if (req.wLength != 0)
1083 					break;
1084 				num  = le16_to_cpu(req.wIndex);
1085 				dir = num & USB_ENDPOINT_DIR_MASK;
1086 				num &= USB_ENDPOINT_NUMBER_MASK;
1087 				if (dir) /* TX */
1088 					num += ci->hw_ep_max/2;
1089 
1090 				spin_unlock(&ci->lock);
1091 				err = usb_ep_set_halt(&ci->ci_hw_ep[num].ep);
1092 				spin_lock(&ci->lock);
1093 				if (!err)
1094 					isr_setup_status_phase(ci);
1095 			} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1096 				if (req.wLength != 0)
1097 					break;
1098 				switch (le16_to_cpu(req.wValue)) {
1099 				case USB_DEVICE_REMOTE_WAKEUP:
1100 					ci->remote_wakeup = 1;
1101 					err = isr_setup_status_phase(ci);
1102 					break;
1103 				case USB_DEVICE_TEST_MODE:
1104 					tmode = le16_to_cpu(req.wIndex) >> 8;
1105 					switch (tmode) {
1106 					case TEST_J:
1107 					case TEST_K:
1108 					case TEST_SE0_NAK:
1109 					case TEST_PACKET:
1110 					case TEST_FORCE_EN:
1111 						ci->test_mode = tmode;
1112 						err = isr_setup_status_phase(
1113 								ci);
1114 						break;
1115 					default:
1116 						break;
1117 					}
1118 				default:
1119 					goto delegate;
1120 				}
1121 			} else {
1122 				goto delegate;
1123 			}
1124 			break;
1125 		default:
1126 delegate:
1127 			if (req.wLength == 0)   /* no data phase */
1128 				ci->ep0_dir = TX;
1129 
1130 			spin_unlock(&ci->lock);
1131 			err = ci->driver->setup(&ci->gadget, &req);
1132 			spin_lock(&ci->lock);
1133 			break;
1134 		}
1135 
1136 		if (err < 0) {
1137 			spin_unlock(&ci->lock);
1138 			if (usb_ep_set_halt(&hwep->ep))
1139 				dev_err(ci->dev, "error: ep_set_halt\n");
1140 			spin_lock(&ci->lock);
1141 		}
1142 	}
1143 }
1144 
1145 /******************************************************************************
1146  * ENDPT block
1147  *****************************************************************************/
1148 /**
1149  * ep_enable: configure endpoint, making it usable
1150  *
1151  * Check usb_ep_enable() at "usb_gadget.h" for details
1152  */
1153 static int ep_enable(struct usb_ep *ep,
1154 		     const struct usb_endpoint_descriptor *desc)
1155 {
1156 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1157 	int retval = 0;
1158 	unsigned long flags;
1159 	u32 cap = 0;
1160 
1161 	if (ep == NULL || desc == NULL)
1162 		return -EINVAL;
1163 
1164 	spin_lock_irqsave(hwep->lock, flags);
1165 
1166 	/* only internal SW should enable ctrl endpts */
1167 
1168 	hwep->ep.desc = desc;
1169 
1170 	if (!list_empty(&hwep->qh.queue))
1171 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1172 
1173 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1174 	hwep->num  = usb_endpoint_num(desc);
1175 	hwep->type = usb_endpoint_type(desc);
1176 
1177 	hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1178 	hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1179 
1180 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1181 		cap |= QH_IOS;
1182 	if (hwep->num)
1183 		cap |= QH_ZLT;
1184 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1185 	/*
1186 	 * For ISO-TX, we set mult at QH as the largest value, and use
1187 	 * MultO at TD as real mult value.
1188 	 */
1189 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1190 		cap |= 3 << __ffs(QH_MULT);
1191 
1192 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1193 
1194 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1195 
1196 	/*
1197 	 * Enable endpoints in the HW other than ep0 as ep0
1198 	 * is always enabled
1199 	 */
1200 	if (hwep->num)
1201 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1202 				       hwep->type);
1203 
1204 	spin_unlock_irqrestore(hwep->lock, flags);
1205 	return retval;
1206 }
1207 
1208 /**
1209  * ep_disable: endpoint is no longer usable
1210  *
1211  * Check usb_ep_disable() at "usb_gadget.h" for details
1212  */
1213 static int ep_disable(struct usb_ep *ep)
1214 {
1215 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1216 	int direction, retval = 0;
1217 	unsigned long flags;
1218 
1219 	if (ep == NULL)
1220 		return -EINVAL;
1221 	else if (hwep->ep.desc == NULL)
1222 		return -EBUSY;
1223 
1224 	spin_lock_irqsave(hwep->lock, flags);
1225 
1226 	/* only internal SW should disable ctrl endpts */
1227 
1228 	direction = hwep->dir;
1229 	do {
1230 		retval |= _ep_nuke(hwep);
1231 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1232 
1233 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1234 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1235 
1236 	} while (hwep->dir != direction);
1237 
1238 	hwep->ep.desc = NULL;
1239 
1240 	spin_unlock_irqrestore(hwep->lock, flags);
1241 	return retval;
1242 }
1243 
1244 /**
1245  * ep_alloc_request: allocate a request object to use with this endpoint
1246  *
1247  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1248  */
1249 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1250 {
1251 	struct ci_hw_req *hwreq = NULL;
1252 
1253 	if (ep == NULL)
1254 		return NULL;
1255 
1256 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1257 	if (hwreq != NULL) {
1258 		INIT_LIST_HEAD(&hwreq->queue);
1259 		INIT_LIST_HEAD(&hwreq->tds);
1260 	}
1261 
1262 	return (hwreq == NULL) ? NULL : &hwreq->req;
1263 }
1264 
1265 /**
1266  * ep_free_request: frees a request object
1267  *
1268  * Check usb_ep_free_request() at "usb_gadget.h" for details
1269  */
1270 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1271 {
1272 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1273 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1274 	struct td_node *node, *tmpnode;
1275 	unsigned long flags;
1276 
1277 	if (ep == NULL || req == NULL) {
1278 		return;
1279 	} else if (!list_empty(&hwreq->queue)) {
1280 		dev_err(hwep->ci->dev, "freeing queued request\n");
1281 		return;
1282 	}
1283 
1284 	spin_lock_irqsave(hwep->lock, flags);
1285 
1286 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1287 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1288 		list_del_init(&node->td);
1289 		node->ptr = NULL;
1290 		kfree(node);
1291 	}
1292 
1293 	kfree(hwreq);
1294 
1295 	spin_unlock_irqrestore(hwep->lock, flags);
1296 }
1297 
1298 /**
1299  * ep_queue: queues (submits) an I/O request to an endpoint
1300  *
1301  * Check usb_ep_queue()* at usb_gadget.h" for details
1302  */
1303 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1304 		    gfp_t __maybe_unused gfp_flags)
1305 {
1306 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1307 	int retval = 0;
1308 	unsigned long flags;
1309 
1310 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1311 		return -EINVAL;
1312 
1313 	spin_lock_irqsave(hwep->lock, flags);
1314 	retval = _ep_queue(ep, req, gfp_flags);
1315 	spin_unlock_irqrestore(hwep->lock, flags);
1316 	return retval;
1317 }
1318 
1319 /**
1320  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1321  *
1322  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1323  */
1324 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1325 {
1326 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1327 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1328 	unsigned long flags;
1329 
1330 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1331 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1332 		list_empty(&hwep->qh.queue))
1333 		return -EINVAL;
1334 
1335 	spin_lock_irqsave(hwep->lock, flags);
1336 
1337 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1338 
1339 	/* pop request */
1340 	list_del_init(&hwreq->queue);
1341 
1342 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1343 
1344 	req->status = -ECONNRESET;
1345 
1346 	if (hwreq->req.complete != NULL) {
1347 		spin_unlock(hwep->lock);
1348 		hwreq->req.complete(&hwep->ep, &hwreq->req);
1349 		spin_lock(hwep->lock);
1350 	}
1351 
1352 	spin_unlock_irqrestore(hwep->lock, flags);
1353 	return 0;
1354 }
1355 
1356 /**
1357  * ep_set_halt: sets the endpoint halt feature
1358  *
1359  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1360  */
1361 static int ep_set_halt(struct usb_ep *ep, int value)
1362 {
1363 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1364 	int direction, retval = 0;
1365 	unsigned long flags;
1366 
1367 	if (ep == NULL || hwep->ep.desc == NULL)
1368 		return -EINVAL;
1369 
1370 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
1371 		return -EOPNOTSUPP;
1372 
1373 	spin_lock_irqsave(hwep->lock, flags);
1374 
1375 #ifndef STALL_IN
1376 	/* g_file_storage MS compliant but g_zero fails chapter 9 compliance */
1377 	if (value && hwep->type == USB_ENDPOINT_XFER_BULK && hwep->dir == TX &&
1378 	    !list_empty(&hwep->qh.queue)) {
1379 		spin_unlock_irqrestore(hwep->lock, flags);
1380 		return -EAGAIN;
1381 	}
1382 #endif
1383 
1384 	direction = hwep->dir;
1385 	do {
1386 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
1387 
1388 		if (!value)
1389 			hwep->wedge = 0;
1390 
1391 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1392 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1393 
1394 	} while (hwep->dir != direction);
1395 
1396 	spin_unlock_irqrestore(hwep->lock, flags);
1397 	return retval;
1398 }
1399 
1400 /**
1401  * ep_set_wedge: sets the halt feature and ignores clear requests
1402  *
1403  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1404  */
1405 static int ep_set_wedge(struct usb_ep *ep)
1406 {
1407 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1408 	unsigned long flags;
1409 
1410 	if (ep == NULL || hwep->ep.desc == NULL)
1411 		return -EINVAL;
1412 
1413 	spin_lock_irqsave(hwep->lock, flags);
1414 	hwep->wedge = 1;
1415 	spin_unlock_irqrestore(hwep->lock, flags);
1416 
1417 	return usb_ep_set_halt(ep);
1418 }
1419 
1420 /**
1421  * ep_fifo_flush: flushes contents of a fifo
1422  *
1423  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1424  */
1425 static void ep_fifo_flush(struct usb_ep *ep)
1426 {
1427 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1428 	unsigned long flags;
1429 
1430 	if (ep == NULL) {
1431 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1432 		return;
1433 	}
1434 
1435 	spin_lock_irqsave(hwep->lock, flags);
1436 
1437 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1438 
1439 	spin_unlock_irqrestore(hwep->lock, flags);
1440 }
1441 
1442 /**
1443  * Endpoint-specific part of the API to the USB controller hardware
1444  * Check "usb_gadget.h" for details
1445  */
1446 static const struct usb_ep_ops usb_ep_ops = {
1447 	.enable	       = ep_enable,
1448 	.disable       = ep_disable,
1449 	.alloc_request = ep_alloc_request,
1450 	.free_request  = ep_free_request,
1451 	.queue	       = ep_queue,
1452 	.dequeue       = ep_dequeue,
1453 	.set_halt      = ep_set_halt,
1454 	.set_wedge     = ep_set_wedge,
1455 	.fifo_flush    = ep_fifo_flush,
1456 };
1457 
1458 /******************************************************************************
1459  * GADGET block
1460  *****************************************************************************/
1461 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1462 {
1463 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1464 	unsigned long flags;
1465 	int gadget_ready = 0;
1466 
1467 	spin_lock_irqsave(&ci->lock, flags);
1468 	ci->vbus_active = is_active;
1469 	if (ci->driver)
1470 		gadget_ready = 1;
1471 	spin_unlock_irqrestore(&ci->lock, flags);
1472 
1473 	if (gadget_ready) {
1474 		if (is_active) {
1475 			pm_runtime_get_sync(&_gadget->dev);
1476 			hw_device_reset(ci, USBMODE_CM_DC);
1477 			hw_device_state(ci, ci->ep0out->qh.dma);
1478 			dev_dbg(ci->dev, "Connected to host\n");
1479 		} else {
1480 			if (ci->driver)
1481 				ci->driver->disconnect(&ci->gadget);
1482 			hw_device_state(ci, 0);
1483 			if (ci->platdata->notify_event)
1484 				ci->platdata->notify_event(ci,
1485 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1486 			_gadget_stop_activity(&ci->gadget);
1487 			pm_runtime_put_sync(&_gadget->dev);
1488 			dev_dbg(ci->dev, "Disconnected from host\n");
1489 		}
1490 	}
1491 
1492 	return 0;
1493 }
1494 
1495 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1496 {
1497 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1498 	unsigned long flags;
1499 	int ret = 0;
1500 
1501 	spin_lock_irqsave(&ci->lock, flags);
1502 	if (!ci->remote_wakeup) {
1503 		ret = -EOPNOTSUPP;
1504 		goto out;
1505 	}
1506 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1507 		ret = -EINVAL;
1508 		goto out;
1509 	}
1510 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1511 out:
1512 	spin_unlock_irqrestore(&ci->lock, flags);
1513 	return ret;
1514 }
1515 
1516 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1517 {
1518 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1519 
1520 	if (ci->transceiver)
1521 		return usb_phy_set_power(ci->transceiver, ma);
1522 	return -ENOTSUPP;
1523 }
1524 
1525 /* Change Data+ pullup status
1526  * this func is used by usb_gadget_connect/disconnet
1527  */
1528 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1529 {
1530 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1531 
1532 	if (!ci->vbus_active)
1533 		return -EOPNOTSUPP;
1534 
1535 	if (is_on)
1536 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1537 	else
1538 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1539 
1540 	return 0;
1541 }
1542 
1543 static int ci_udc_start(struct usb_gadget *gadget,
1544 			 struct usb_gadget_driver *driver);
1545 static int ci_udc_stop(struct usb_gadget *gadget,
1546 			struct usb_gadget_driver *driver);
1547 /**
1548  * Device operations part of the API to the USB controller hardware,
1549  * which don't involve endpoints (or i/o)
1550  * Check  "usb_gadget.h" for details
1551  */
1552 static const struct usb_gadget_ops usb_gadget_ops = {
1553 	.vbus_session	= ci_udc_vbus_session,
1554 	.wakeup		= ci_udc_wakeup,
1555 	.pullup		= ci_udc_pullup,
1556 	.vbus_draw	= ci_udc_vbus_draw,
1557 	.udc_start	= ci_udc_start,
1558 	.udc_stop	= ci_udc_stop,
1559 };
1560 
1561 static int init_eps(struct ci_hdrc *ci)
1562 {
1563 	int retval = 0, i, j;
1564 
1565 	for (i = 0; i < ci->hw_ep_max/2; i++)
1566 		for (j = RX; j <= TX; j++) {
1567 			int k = i + j * ci->hw_ep_max/2;
1568 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1569 
1570 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1571 					(j == TX)  ? "in" : "out");
1572 
1573 			hwep->ci          = ci;
1574 			hwep->lock         = &ci->lock;
1575 			hwep->td_pool      = ci->td_pool;
1576 
1577 			hwep->ep.name      = hwep->name;
1578 			hwep->ep.ops       = &usb_ep_ops;
1579 			/*
1580 			 * for ep0: maxP defined in desc, for other
1581 			 * eps, maxP is set by epautoconfig() called
1582 			 * by gadget layer
1583 			 */
1584 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1585 
1586 			INIT_LIST_HEAD(&hwep->qh.queue);
1587 			hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1588 						     &hwep->qh.dma);
1589 			if (hwep->qh.ptr == NULL)
1590 				retval = -ENOMEM;
1591 			else
1592 				memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1593 
1594 			/*
1595 			 * set up shorthands for ep0 out and in endpoints,
1596 			 * don't add to gadget's ep_list
1597 			 */
1598 			if (i == 0) {
1599 				if (j == RX)
1600 					ci->ep0out = hwep;
1601 				else
1602 					ci->ep0in = hwep;
1603 
1604 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1605 				continue;
1606 			}
1607 
1608 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1609 		}
1610 
1611 	return retval;
1612 }
1613 
1614 static void destroy_eps(struct ci_hdrc *ci)
1615 {
1616 	int i;
1617 
1618 	for (i = 0; i < ci->hw_ep_max; i++) {
1619 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1620 
1621 		if (hwep->pending_td)
1622 			free_pending_td(hwep);
1623 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1624 	}
1625 }
1626 
1627 /**
1628  * ci_udc_start: register a gadget driver
1629  * @gadget: our gadget
1630  * @driver: the driver being registered
1631  *
1632  * Interrupts are enabled here.
1633  */
1634 static int ci_udc_start(struct usb_gadget *gadget,
1635 			 struct usb_gadget_driver *driver)
1636 {
1637 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1638 	unsigned long flags;
1639 	int retval = -ENOMEM;
1640 
1641 	if (driver->disconnect == NULL)
1642 		return -EINVAL;
1643 
1644 
1645 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1646 	retval = usb_ep_enable(&ci->ep0out->ep);
1647 	if (retval)
1648 		return retval;
1649 
1650 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1651 	retval = usb_ep_enable(&ci->ep0in->ep);
1652 	if (retval)
1653 		return retval;
1654 
1655 	ci->driver = driver;
1656 	pm_runtime_get_sync(&ci->gadget.dev);
1657 	if (ci->vbus_active) {
1658 		spin_lock_irqsave(&ci->lock, flags);
1659 		hw_device_reset(ci, USBMODE_CM_DC);
1660 	} else {
1661 		pm_runtime_put_sync(&ci->gadget.dev);
1662 		return retval;
1663 	}
1664 
1665 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1666 	spin_unlock_irqrestore(&ci->lock, flags);
1667 	if (retval)
1668 		pm_runtime_put_sync(&ci->gadget.dev);
1669 
1670 	return retval;
1671 }
1672 
1673 /**
1674  * ci_udc_stop: unregister a gadget driver
1675  */
1676 static int ci_udc_stop(struct usb_gadget *gadget,
1677 			struct usb_gadget_driver *driver)
1678 {
1679 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1680 	unsigned long flags;
1681 
1682 	spin_lock_irqsave(&ci->lock, flags);
1683 
1684 	if (ci->vbus_active) {
1685 		hw_device_state(ci, 0);
1686 		if (ci->platdata->notify_event)
1687 			ci->platdata->notify_event(ci,
1688 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1689 		spin_unlock_irqrestore(&ci->lock, flags);
1690 		_gadget_stop_activity(&ci->gadget);
1691 		spin_lock_irqsave(&ci->lock, flags);
1692 		pm_runtime_put(&ci->gadget.dev);
1693 	}
1694 
1695 	ci->driver = NULL;
1696 	spin_unlock_irqrestore(&ci->lock, flags);
1697 
1698 	return 0;
1699 }
1700 
1701 /******************************************************************************
1702  * BUS block
1703  *****************************************************************************/
1704 /**
1705  * udc_irq: ci interrupt handler
1706  *
1707  * This function returns IRQ_HANDLED if the IRQ has been handled
1708  * It locks access to registers
1709  */
1710 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1711 {
1712 	irqreturn_t retval;
1713 	u32 intr;
1714 
1715 	if (ci == NULL)
1716 		return IRQ_HANDLED;
1717 
1718 	spin_lock(&ci->lock);
1719 
1720 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1721 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1722 				USBMODE_CM_DC) {
1723 			spin_unlock(&ci->lock);
1724 			return IRQ_NONE;
1725 		}
1726 	}
1727 	intr = hw_test_and_clear_intr_active(ci);
1728 
1729 	if (intr) {
1730 		/* order defines priority - do NOT change it */
1731 		if (USBi_URI & intr)
1732 			isr_reset_handler(ci);
1733 
1734 		if (USBi_PCI & intr) {
1735 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1736 				USB_SPEED_HIGH : USB_SPEED_FULL;
1737 			if (ci->suspended && ci->driver->resume) {
1738 				spin_unlock(&ci->lock);
1739 				ci->driver->resume(&ci->gadget);
1740 				spin_lock(&ci->lock);
1741 				ci->suspended = 0;
1742 			}
1743 		}
1744 
1745 		if (USBi_UI  & intr)
1746 			isr_tr_complete_handler(ci);
1747 
1748 		if (USBi_SLI & intr) {
1749 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1750 			    ci->driver->suspend) {
1751 				ci->suspended = 1;
1752 				spin_unlock(&ci->lock);
1753 				ci->driver->suspend(&ci->gadget);
1754 				spin_lock(&ci->lock);
1755 			}
1756 		}
1757 		retval = IRQ_HANDLED;
1758 	} else {
1759 		retval = IRQ_NONE;
1760 	}
1761 	spin_unlock(&ci->lock);
1762 
1763 	return retval;
1764 }
1765 
1766 /**
1767  * udc_start: initialize gadget role
1768  * @ci: chipidea controller
1769  */
1770 static int udc_start(struct ci_hdrc *ci)
1771 {
1772 	struct device *dev = ci->dev;
1773 	int retval = 0;
1774 
1775 	spin_lock_init(&ci->lock);
1776 
1777 	ci->gadget.ops          = &usb_gadget_ops;
1778 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1779 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1780 	ci->gadget.is_otg       = 0;
1781 	ci->gadget.name         = ci->platdata->name;
1782 
1783 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1784 
1785 	/* alloc resources */
1786 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1787 				       sizeof(struct ci_hw_qh),
1788 				       64, CI_HDRC_PAGE_SIZE);
1789 	if (ci->qh_pool == NULL)
1790 		return -ENOMEM;
1791 
1792 	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1793 				       sizeof(struct ci_hw_td),
1794 				       64, CI_HDRC_PAGE_SIZE);
1795 	if (ci->td_pool == NULL) {
1796 		retval = -ENOMEM;
1797 		goto free_qh_pool;
1798 	}
1799 
1800 	retval = init_eps(ci);
1801 	if (retval)
1802 		goto free_pools;
1803 
1804 	ci->gadget.ep0 = &ci->ep0in->ep;
1805 
1806 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1807 	if (retval)
1808 		goto destroy_eps;
1809 
1810 	pm_runtime_no_callbacks(&ci->gadget.dev);
1811 	pm_runtime_enable(&ci->gadget.dev);
1812 
1813 	return retval;
1814 
1815 destroy_eps:
1816 	destroy_eps(ci);
1817 free_pools:
1818 	dma_pool_destroy(ci->td_pool);
1819 free_qh_pool:
1820 	dma_pool_destroy(ci->qh_pool);
1821 	return retval;
1822 }
1823 
1824 /**
1825  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1826  *
1827  * No interrupts active, the IRQ has been released
1828  */
1829 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1830 {
1831 	if (!ci->roles[CI_ROLE_GADGET])
1832 		return;
1833 
1834 	usb_del_gadget_udc(&ci->gadget);
1835 
1836 	destroy_eps(ci);
1837 
1838 	dma_pool_destroy(ci->td_pool);
1839 	dma_pool_destroy(ci->qh_pool);
1840 
1841 	if (ci->transceiver) {
1842 		otg_set_peripheral(ci->transceiver->otg, NULL);
1843 		if (ci->global_phy)
1844 			usb_put_phy(ci->transceiver);
1845 	}
1846 }
1847 
1848 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1849 {
1850 	if (ci->is_otg) {
1851 		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
1852 		ci_enable_otg_interrupt(ci, OTGSC_BSVIE);
1853 	}
1854 
1855 	return 0;
1856 }
1857 
1858 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1859 {
1860 	if (ci->is_otg) {
1861 		/* host doesn't care B_SESSION_VALID event */
1862 		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
1863 		ci_disable_otg_interrupt(ci, OTGSC_BSVIE);
1864 	}
1865 }
1866 
1867 /**
1868  * ci_hdrc_gadget_init - initialize device related bits
1869  * ci: the controller
1870  *
1871  * This function initializes the gadget, if the device is "device capable".
1872  */
1873 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1874 {
1875 	struct ci_role_driver *rdrv;
1876 
1877 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1878 		return -ENXIO;
1879 
1880 	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1881 	if (!rdrv)
1882 		return -ENOMEM;
1883 
1884 	rdrv->start	= udc_id_switch_for_device;
1885 	rdrv->stop	= udc_id_switch_for_host;
1886 	rdrv->irq	= udc_irq;
1887 	rdrv->name	= "gadget";
1888 	ci->roles[CI_ROLE_GADGET] = rdrv;
1889 
1890 	return udc_start(ci);
1891 }
1892