xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision eb3fcf00)
1 /*
2  * udc.c - ChipIdea UDC driver
3  *
4  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
5  *
6  * Author: David Lopo
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/dmapool.h>
16 #include <linux/err.h>
17 #include <linux/irqreturn.h>
18 #include <linux/kernel.h>
19 #include <linux/slab.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/usb/ch9.h>
22 #include <linux/usb/gadget.h>
23 #include <linux/usb/otg-fsm.h>
24 #include <linux/usb/chipidea.h>
25 
26 #include "ci.h"
27 #include "udc.h"
28 #include "bits.h"
29 #include "debug.h"
30 #include "otg.h"
31 #include "otg_fsm.h"
32 
33 /* control endpoint description */
34 static const struct usb_endpoint_descriptor
35 ctrl_endpt_out_desc = {
36 	.bLength         = USB_DT_ENDPOINT_SIZE,
37 	.bDescriptorType = USB_DT_ENDPOINT,
38 
39 	.bEndpointAddress = USB_DIR_OUT,
40 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
41 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
42 };
43 
44 static const struct usb_endpoint_descriptor
45 ctrl_endpt_in_desc = {
46 	.bLength         = USB_DT_ENDPOINT_SIZE,
47 	.bDescriptorType = USB_DT_ENDPOINT,
48 
49 	.bEndpointAddress = USB_DIR_IN,
50 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
51 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
52 };
53 
54 /**
55  * hw_ep_bit: calculates the bit number
56  * @num: endpoint number
57  * @dir: endpoint direction
58  *
59  * This function returns bit number
60  */
61 static inline int hw_ep_bit(int num, int dir)
62 {
63 	return num + (dir ? 16 : 0);
64 }
65 
66 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
67 {
68 	int fill = 16 - ci->hw_ep_max / 2;
69 
70 	if (n >= ci->hw_ep_max / 2)
71 		n += fill;
72 
73 	return n;
74 }
75 
76 /**
77  * hw_device_state: enables/disables interrupts (execute without interruption)
78  * @dma: 0 => disable, !0 => enable and set dma engine
79  *
80  * This function returns an error code
81  */
82 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
83 {
84 	if (dma) {
85 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
86 		/* interrupt, error, port change, reset, sleep/suspend */
87 		hw_write(ci, OP_USBINTR, ~0,
88 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
89 	} else {
90 		hw_write(ci, OP_USBINTR, ~0, 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_test_and_clear_complete: test & clear complete status (execute without
246  *                             interruption)
247  * @n: endpoint number
248  *
249  * This function returns complete status
250  */
251 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
252 {
253 	n = ep_to_bit(ci, n);
254 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
255 }
256 
257 /**
258  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
259  *                                without interruption)
260  *
261  * This function returns active interrutps
262  */
263 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
264 {
265 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
266 
267 	hw_write(ci, OP_USBSTS, ~0, reg);
268 	return reg;
269 }
270 
271 /**
272  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
273  *                                interruption)
274  *
275  * This function returns guard value
276  */
277 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
278 {
279 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
280 }
281 
282 /**
283  * hw_test_and_set_setup_guard: test & set setup guard (execute without
284  *                              interruption)
285  *
286  * This function returns guard value
287  */
288 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
289 {
290 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
291 }
292 
293 /**
294  * hw_usb_set_address: configures USB address (execute without interruption)
295  * @value: new USB address
296  *
297  * This function explicitly sets the address, without the "USBADRA" (advance)
298  * feature, which is not supported by older versions of the controller.
299  */
300 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
301 {
302 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
303 		 value << __ffs(DEVICEADDR_USBADR));
304 }
305 
306 /**
307  * hw_usb_reset: restart device after a bus reset (execute without
308  *               interruption)
309  *
310  * This function returns an error code
311  */
312 static int hw_usb_reset(struct ci_hdrc *ci)
313 {
314 	hw_usb_set_address(ci, 0);
315 
316 	/* ESS flushes only at end?!? */
317 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
318 
319 	/* clear setup token semaphores */
320 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
321 
322 	/* clear complete status */
323 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
324 
325 	/* wait until all bits cleared */
326 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
327 		udelay(10);             /* not RTOS friendly */
328 
329 	/* reset all endpoints ? */
330 
331 	/* reset internal status and wait for further instructions
332 	   no need to verify the port reset status (ESS does it) */
333 
334 	return 0;
335 }
336 
337 /******************************************************************************
338  * UTIL block
339  *****************************************************************************/
340 
341 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
342 			  unsigned length)
343 {
344 	int i;
345 	u32 temp;
346 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
347 						  GFP_ATOMIC);
348 
349 	if (node == NULL)
350 		return -ENOMEM;
351 
352 	node->ptr = dma_pool_alloc(hwep->td_pool, GFP_ATOMIC,
353 				   &node->dma);
354 	if (node->ptr == NULL) {
355 		kfree(node);
356 		return -ENOMEM;
357 	}
358 
359 	memset(node->ptr, 0, sizeof(struct ci_hw_td));
360 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
361 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
362 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
363 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
364 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
365 
366 		if (hwreq->req.length == 0
367 				|| hwreq->req.length % hwep->ep.maxpacket)
368 			mul++;
369 		node->ptr->token |= mul << __ffs(TD_MULTO);
370 	}
371 
372 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
373 	if (length) {
374 		node->ptr->page[0] = cpu_to_le32(temp);
375 		for (i = 1; i < TD_PAGE_COUNT; i++) {
376 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
377 			page &= ~TD_RESERVED_MASK;
378 			node->ptr->page[i] = cpu_to_le32(page);
379 		}
380 	}
381 
382 	hwreq->req.actual += length;
383 
384 	if (!list_empty(&hwreq->tds)) {
385 		/* get the last entry */
386 		lastnode = list_entry(hwreq->tds.prev,
387 				struct td_node, td);
388 		lastnode->ptr->next = cpu_to_le32(node->dma);
389 	}
390 
391 	INIT_LIST_HEAD(&node->td);
392 	list_add_tail(&node->td, &hwreq->tds);
393 
394 	return 0;
395 }
396 
397 /**
398  * _usb_addr: calculates endpoint address from direction & number
399  * @ep:  endpoint
400  */
401 static inline u8 _usb_addr(struct ci_hw_ep *ep)
402 {
403 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
404 }
405 
406 /**
407  * _hardware_queue: configures a request at hardware level
408  * @gadget: gadget
409  * @hwep:   endpoint
410  *
411  * This function returns an error code
412  */
413 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
414 {
415 	struct ci_hdrc *ci = hwep->ci;
416 	int ret = 0;
417 	unsigned rest = hwreq->req.length;
418 	int pages = TD_PAGE_COUNT;
419 	struct td_node *firstnode, *lastnode;
420 
421 	/* don't queue twice */
422 	if (hwreq->req.status == -EALREADY)
423 		return -EALREADY;
424 
425 	hwreq->req.status = -EALREADY;
426 
427 	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
428 	if (ret)
429 		return ret;
430 
431 	/*
432 	 * The first buffer could be not page aligned.
433 	 * In that case we have to span into one extra td.
434 	 */
435 	if (hwreq->req.dma % PAGE_SIZE)
436 		pages--;
437 
438 	if (rest == 0)
439 		add_td_to_list(hwep, hwreq, 0);
440 
441 	while (rest > 0) {
442 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
443 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
444 		add_td_to_list(hwep, hwreq, count);
445 		rest -= count;
446 	}
447 
448 	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
449 	    && (hwreq->req.length % hwep->ep.maxpacket == 0))
450 		add_td_to_list(hwep, hwreq, 0);
451 
452 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
453 
454 	lastnode = list_entry(hwreq->tds.prev,
455 		struct td_node, td);
456 
457 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
458 	if (!hwreq->req.no_interrupt)
459 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
460 	wmb();
461 
462 	hwreq->req.actual = 0;
463 	if (!list_empty(&hwep->qh.queue)) {
464 		struct ci_hw_req *hwreqprev;
465 		int n = hw_ep_bit(hwep->num, hwep->dir);
466 		int tmp_stat;
467 		struct td_node *prevlastnode;
468 		u32 next = firstnode->dma & TD_ADDR_MASK;
469 
470 		hwreqprev = list_entry(hwep->qh.queue.prev,
471 				struct ci_hw_req, queue);
472 		prevlastnode = list_entry(hwreqprev->tds.prev,
473 				struct td_node, td);
474 
475 		prevlastnode->ptr->next = cpu_to_le32(next);
476 		wmb();
477 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
478 			goto done;
479 		do {
480 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
481 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
482 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
483 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
484 		if (tmp_stat)
485 			goto done;
486 	}
487 
488 	/*  QH configuration */
489 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
490 	hwep->qh.ptr->td.token &=
491 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
492 
493 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
494 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
495 
496 		if (hwreq->req.length == 0
497 				|| hwreq->req.length % hwep->ep.maxpacket)
498 			mul++;
499 		hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
500 	}
501 
502 	wmb();   /* synchronize before ep prime */
503 
504 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
505 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
506 done:
507 	return ret;
508 }
509 
510 /*
511  * free_pending_td: remove a pending request for the endpoint
512  * @hwep: endpoint
513  */
514 static void free_pending_td(struct ci_hw_ep *hwep)
515 {
516 	struct td_node *pending = hwep->pending_td;
517 
518 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
519 	hwep->pending_td = NULL;
520 	kfree(pending);
521 }
522 
523 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
524 					   struct td_node *node)
525 {
526 	hwep->qh.ptr->td.next = node->dma;
527 	hwep->qh.ptr->td.token &=
528 		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
529 
530 	/* Synchronize before ep prime */
531 	wmb();
532 
533 	return hw_ep_prime(ci, hwep->num, hwep->dir,
534 				hwep->type == USB_ENDPOINT_XFER_CONTROL);
535 }
536 
537 /**
538  * _hardware_dequeue: handles a request at hardware level
539  * @gadget: gadget
540  * @hwep:   endpoint
541  *
542  * This function returns an error code
543  */
544 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
545 {
546 	u32 tmptoken;
547 	struct td_node *node, *tmpnode;
548 	unsigned remaining_length;
549 	unsigned actual = hwreq->req.length;
550 	struct ci_hdrc *ci = hwep->ci;
551 
552 	if (hwreq->req.status != -EALREADY)
553 		return -EINVAL;
554 
555 	hwreq->req.status = 0;
556 
557 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
558 		tmptoken = le32_to_cpu(node->ptr->token);
559 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
560 			int n = hw_ep_bit(hwep->num, hwep->dir);
561 
562 			if (ci->rev == CI_REVISION_24)
563 				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
564 					reprime_dtd(ci, hwep, node);
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 			usb_gadget_giveback_request(&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 static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
660 {
661 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
662 	int direction, retval = 0;
663 	unsigned long flags;
664 
665 	if (ep == NULL || hwep->ep.desc == NULL)
666 		return -EINVAL;
667 
668 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
669 		return -EOPNOTSUPP;
670 
671 	spin_lock_irqsave(hwep->lock, flags);
672 
673 	if (value && hwep->dir == TX && check_transfer &&
674 		!list_empty(&hwep->qh.queue) &&
675 			!usb_endpoint_xfer_control(hwep->ep.desc)) {
676 		spin_unlock_irqrestore(hwep->lock, flags);
677 		return -EAGAIN;
678 	}
679 
680 	direction = hwep->dir;
681 	do {
682 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
683 
684 		if (!value)
685 			hwep->wedge = 0;
686 
687 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
688 			hwep->dir = (hwep->dir == TX) ? RX : TX;
689 
690 	} while (hwep->dir != direction);
691 
692 	spin_unlock_irqrestore(hwep->lock, flags);
693 	return retval;
694 }
695 
696 
697 /**
698  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
699  * @gadget: gadget
700  *
701  * This function returns an error code
702  */
703 static int _gadget_stop_activity(struct usb_gadget *gadget)
704 {
705 	struct usb_ep *ep;
706 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
707 	unsigned long flags;
708 
709 	spin_lock_irqsave(&ci->lock, flags);
710 	ci->gadget.speed = USB_SPEED_UNKNOWN;
711 	ci->remote_wakeup = 0;
712 	ci->suspended = 0;
713 	spin_unlock_irqrestore(&ci->lock, flags);
714 
715 	/* flush all endpoints */
716 	gadget_for_each_ep(ep, gadget) {
717 		usb_ep_fifo_flush(ep);
718 	}
719 	usb_ep_fifo_flush(&ci->ep0out->ep);
720 	usb_ep_fifo_flush(&ci->ep0in->ep);
721 
722 	/* make sure to disable all endpoints */
723 	gadget_for_each_ep(ep, gadget) {
724 		usb_ep_disable(ep);
725 	}
726 
727 	if (ci->status != NULL) {
728 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
729 		ci->status = NULL;
730 	}
731 
732 	return 0;
733 }
734 
735 /******************************************************************************
736  * ISR block
737  *****************************************************************************/
738 /**
739  * isr_reset_handler: USB reset interrupt handler
740  * @ci: UDC device
741  *
742  * This function resets USB engine after a bus reset occurred
743  */
744 static void isr_reset_handler(struct ci_hdrc *ci)
745 __releases(ci->lock)
746 __acquires(ci->lock)
747 {
748 	int retval;
749 
750 	spin_unlock(&ci->lock);
751 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
752 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
753 
754 	retval = _gadget_stop_activity(&ci->gadget);
755 	if (retval)
756 		goto done;
757 
758 	retval = hw_usb_reset(ci);
759 	if (retval)
760 		goto done;
761 
762 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
763 	if (ci->status == NULL)
764 		retval = -ENOMEM;
765 
766 done:
767 	spin_lock(&ci->lock);
768 
769 	if (retval)
770 		dev_err(ci->dev, "error: %i\n", retval);
771 }
772 
773 /**
774  * isr_get_status_complete: get_status request complete function
775  * @ep:  endpoint
776  * @req: request handled
777  *
778  * Caller must release lock
779  */
780 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
781 {
782 	if (ep == NULL || req == NULL)
783 		return;
784 
785 	kfree(req->buf);
786 	usb_ep_free_request(ep, req);
787 }
788 
789 /**
790  * _ep_queue: queues (submits) an I/O request to an endpoint
791  *
792  * Caller must hold lock
793  */
794 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
795 		    gfp_t __maybe_unused gfp_flags)
796 {
797 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
798 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
799 	struct ci_hdrc *ci = hwep->ci;
800 	int retval = 0;
801 
802 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
803 		return -EINVAL;
804 
805 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
806 		if (req->length)
807 			hwep = (ci->ep0_dir == RX) ?
808 			       ci->ep0out : ci->ep0in;
809 		if (!list_empty(&hwep->qh.queue)) {
810 			_ep_nuke(hwep);
811 			retval = -EOVERFLOW;
812 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
813 				 _usb_addr(hwep));
814 		}
815 	}
816 
817 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
818 	    hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
819 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
820 		return -EMSGSIZE;
821 	}
822 
823 	/* first nuke then test link, e.g. previous status has not sent */
824 	if (!list_empty(&hwreq->queue)) {
825 		dev_err(hwep->ci->dev, "request already in queue\n");
826 		return -EBUSY;
827 	}
828 
829 	/* push request */
830 	hwreq->req.status = -EINPROGRESS;
831 	hwreq->req.actual = 0;
832 
833 	retval = _hardware_enqueue(hwep, hwreq);
834 
835 	if (retval == -EALREADY)
836 		retval = 0;
837 	if (!retval)
838 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
839 
840 	return retval;
841 }
842 
843 /**
844  * isr_get_status_response: get_status request response
845  * @ci: ci struct
846  * @setup: setup request packet
847  *
848  * This function returns an error code
849  */
850 static int isr_get_status_response(struct ci_hdrc *ci,
851 				   struct usb_ctrlrequest *setup)
852 __releases(hwep->lock)
853 __acquires(hwep->lock)
854 {
855 	struct ci_hw_ep *hwep = ci->ep0in;
856 	struct usb_request *req = NULL;
857 	gfp_t gfp_flags = GFP_ATOMIC;
858 	int dir, num, retval;
859 
860 	if (hwep == NULL || setup == NULL)
861 		return -EINVAL;
862 
863 	spin_unlock(hwep->lock);
864 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
865 	spin_lock(hwep->lock);
866 	if (req == NULL)
867 		return -ENOMEM;
868 
869 	req->complete = isr_get_status_complete;
870 	req->length   = 2;
871 	req->buf      = kzalloc(req->length, gfp_flags);
872 	if (req->buf == NULL) {
873 		retval = -ENOMEM;
874 		goto err_free_req;
875 	}
876 
877 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
878 		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
879 			ci->gadget.is_selfpowered;
880 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
881 		   == USB_RECIP_ENDPOINT) {
882 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
883 			TX : RX;
884 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
885 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
886 	}
887 	/* else do nothing; reserved for future use */
888 
889 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
890 	if (retval)
891 		goto err_free_buf;
892 
893 	return 0;
894 
895  err_free_buf:
896 	kfree(req->buf);
897  err_free_req:
898 	spin_unlock(hwep->lock);
899 	usb_ep_free_request(&hwep->ep, req);
900 	spin_lock(hwep->lock);
901 	return retval;
902 }
903 
904 /**
905  * isr_setup_status_complete: setup_status request complete function
906  * @ep:  endpoint
907  * @req: request handled
908  *
909  * Caller must release lock. Put the port in test mode if test mode
910  * feature is selected.
911  */
912 static void
913 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
914 {
915 	struct ci_hdrc *ci = req->context;
916 	unsigned long flags;
917 
918 	if (ci->setaddr) {
919 		hw_usb_set_address(ci, ci->address);
920 		ci->setaddr = false;
921 		if (ci->address)
922 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
923 	}
924 
925 	spin_lock_irqsave(&ci->lock, flags);
926 	if (ci->test_mode)
927 		hw_port_test_set(ci, ci->test_mode);
928 	spin_unlock_irqrestore(&ci->lock, flags);
929 }
930 
931 /**
932  * isr_setup_status_phase: queues the status phase of a setup transation
933  * @ci: ci struct
934  *
935  * This function returns an error code
936  */
937 static int isr_setup_status_phase(struct ci_hdrc *ci)
938 {
939 	int retval;
940 	struct ci_hw_ep *hwep;
941 
942 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
943 	ci->status->context = ci;
944 	ci->status->complete = isr_setup_status_complete;
945 
946 	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
947 
948 	return retval;
949 }
950 
951 /**
952  * isr_tr_complete_low: transaction complete low level handler
953  * @hwep: endpoint
954  *
955  * This function returns an error code
956  * Caller must hold lock
957  */
958 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
959 __releases(hwep->lock)
960 __acquires(hwep->lock)
961 {
962 	struct ci_hw_req *hwreq, *hwreqtemp;
963 	struct ci_hw_ep *hweptemp = hwep;
964 	int retval = 0;
965 
966 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
967 			queue) {
968 		retval = _hardware_dequeue(hwep, hwreq);
969 		if (retval < 0)
970 			break;
971 		list_del_init(&hwreq->queue);
972 		if (hwreq->req.complete != NULL) {
973 			spin_unlock(hwep->lock);
974 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
975 					hwreq->req.length)
976 				hweptemp = hwep->ci->ep0in;
977 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
978 			spin_lock(hwep->lock);
979 		}
980 	}
981 
982 	if (retval == -EBUSY)
983 		retval = 0;
984 
985 	return retval;
986 }
987 
988 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
989 {
990 	dev_warn(&ci->gadget.dev,
991 		"connect the device to an alternate port if you want HNP\n");
992 	return isr_setup_status_phase(ci);
993 }
994 
995 /**
996  * isr_setup_packet_handler: setup packet handler
997  * @ci: UDC descriptor
998  *
999  * This function handles setup packet
1000  */
1001 static void isr_setup_packet_handler(struct ci_hdrc *ci)
1002 __releases(ci->lock)
1003 __acquires(ci->lock)
1004 {
1005 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1006 	struct usb_ctrlrequest req;
1007 	int type, num, dir, err = -EINVAL;
1008 	u8 tmode = 0;
1009 
1010 	/*
1011 	 * Flush data and handshake transactions of previous
1012 	 * setup packet.
1013 	 */
1014 	_ep_nuke(ci->ep0out);
1015 	_ep_nuke(ci->ep0in);
1016 
1017 	/* read_setup_packet */
1018 	do {
1019 		hw_test_and_set_setup_guard(ci);
1020 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1021 	} while (!hw_test_and_clear_setup_guard(ci));
1022 
1023 	type = req.bRequestType;
1024 
1025 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1026 
1027 	switch (req.bRequest) {
1028 	case USB_REQ_CLEAR_FEATURE:
1029 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1030 				le16_to_cpu(req.wValue) ==
1031 				USB_ENDPOINT_HALT) {
1032 			if (req.wLength != 0)
1033 				break;
1034 			num  = le16_to_cpu(req.wIndex);
1035 			dir = num & USB_ENDPOINT_DIR_MASK;
1036 			num &= USB_ENDPOINT_NUMBER_MASK;
1037 			if (dir) /* TX */
1038 				num += ci->hw_ep_max / 2;
1039 			if (!ci->ci_hw_ep[num].wedge) {
1040 				spin_unlock(&ci->lock);
1041 				err = usb_ep_clear_halt(
1042 					&ci->ci_hw_ep[num].ep);
1043 				spin_lock(&ci->lock);
1044 				if (err)
1045 					break;
1046 			}
1047 			err = isr_setup_status_phase(ci);
1048 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1049 				le16_to_cpu(req.wValue) ==
1050 				USB_DEVICE_REMOTE_WAKEUP) {
1051 			if (req.wLength != 0)
1052 				break;
1053 			ci->remote_wakeup = 0;
1054 			err = isr_setup_status_phase(ci);
1055 		} else {
1056 			goto delegate;
1057 		}
1058 		break;
1059 	case USB_REQ_GET_STATUS:
1060 		if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
1061 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1062 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1063 			goto delegate;
1064 		if (le16_to_cpu(req.wLength) != 2 ||
1065 		    le16_to_cpu(req.wValue)  != 0)
1066 			break;
1067 		err = isr_get_status_response(ci, &req);
1068 		break;
1069 	case USB_REQ_SET_ADDRESS:
1070 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1071 			goto delegate;
1072 		if (le16_to_cpu(req.wLength) != 0 ||
1073 		    le16_to_cpu(req.wIndex)  != 0)
1074 			break;
1075 		ci->address = (u8)le16_to_cpu(req.wValue);
1076 		ci->setaddr = true;
1077 		err = isr_setup_status_phase(ci);
1078 		break;
1079 	case USB_REQ_SET_FEATURE:
1080 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1081 				le16_to_cpu(req.wValue) ==
1082 				USB_ENDPOINT_HALT) {
1083 			if (req.wLength != 0)
1084 				break;
1085 			num  = le16_to_cpu(req.wIndex);
1086 			dir = num & USB_ENDPOINT_DIR_MASK;
1087 			num &= USB_ENDPOINT_NUMBER_MASK;
1088 			if (dir) /* TX */
1089 				num += ci->hw_ep_max / 2;
1090 
1091 			spin_unlock(&ci->lock);
1092 			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1093 			spin_lock(&ci->lock);
1094 			if (!err)
1095 				isr_setup_status_phase(ci);
1096 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1097 			if (req.wLength != 0)
1098 				break;
1099 			switch (le16_to_cpu(req.wValue)) {
1100 			case USB_DEVICE_REMOTE_WAKEUP:
1101 				ci->remote_wakeup = 1;
1102 				err = isr_setup_status_phase(ci);
1103 				break;
1104 			case USB_DEVICE_TEST_MODE:
1105 				tmode = le16_to_cpu(req.wIndex) >> 8;
1106 				switch (tmode) {
1107 				case TEST_J:
1108 				case TEST_K:
1109 				case TEST_SE0_NAK:
1110 				case TEST_PACKET:
1111 				case TEST_FORCE_EN:
1112 					ci->test_mode = tmode;
1113 					err = isr_setup_status_phase(
1114 							ci);
1115 					break;
1116 				default:
1117 					break;
1118 				}
1119 				break;
1120 			case USB_DEVICE_B_HNP_ENABLE:
1121 				if (ci_otg_is_fsm_mode(ci)) {
1122 					ci->gadget.b_hnp_enable = 1;
1123 					err = isr_setup_status_phase(
1124 							ci);
1125 				}
1126 				break;
1127 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1128 				if (ci_otg_is_fsm_mode(ci))
1129 					err = otg_a_alt_hnp_support(ci);
1130 				break;
1131 			case USB_DEVICE_A_HNP_SUPPORT:
1132 				if (ci_otg_is_fsm_mode(ci)) {
1133 					ci->gadget.a_hnp_support = 1;
1134 					err = isr_setup_status_phase(
1135 							ci);
1136 				}
1137 				break;
1138 			default:
1139 				goto delegate;
1140 			}
1141 		} else {
1142 			goto delegate;
1143 		}
1144 		break;
1145 	default:
1146 delegate:
1147 		if (req.wLength == 0)   /* no data phase */
1148 			ci->ep0_dir = TX;
1149 
1150 		spin_unlock(&ci->lock);
1151 		err = ci->driver->setup(&ci->gadget, &req);
1152 		spin_lock(&ci->lock);
1153 		break;
1154 	}
1155 
1156 	if (err < 0) {
1157 		spin_unlock(&ci->lock);
1158 		if (_ep_set_halt(&hwep->ep, 1, false))
1159 			dev_err(ci->dev, "error: _ep_set_halt\n");
1160 		spin_lock(&ci->lock);
1161 	}
1162 }
1163 
1164 /**
1165  * isr_tr_complete_handler: transaction complete interrupt handler
1166  * @ci: UDC descriptor
1167  *
1168  * This function handles traffic events
1169  */
1170 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1171 __releases(ci->lock)
1172 __acquires(ci->lock)
1173 {
1174 	unsigned i;
1175 	int err;
1176 
1177 	for (i = 0; i < ci->hw_ep_max; i++) {
1178 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1179 
1180 		if (hwep->ep.desc == NULL)
1181 			continue;   /* not configured */
1182 
1183 		if (hw_test_and_clear_complete(ci, i)) {
1184 			err = isr_tr_complete_low(hwep);
1185 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1186 				if (err > 0)   /* needs status phase */
1187 					err = isr_setup_status_phase(ci);
1188 				if (err < 0) {
1189 					spin_unlock(&ci->lock);
1190 					if (_ep_set_halt(&hwep->ep, 1, false))
1191 						dev_err(ci->dev,
1192 						"error: _ep_set_halt\n");
1193 					spin_lock(&ci->lock);
1194 				}
1195 			}
1196 		}
1197 
1198 		/* Only handle setup packet below */
1199 		if (i == 0 &&
1200 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1201 			isr_setup_packet_handler(ci);
1202 	}
1203 }
1204 
1205 /******************************************************************************
1206  * ENDPT block
1207  *****************************************************************************/
1208 /**
1209  * ep_enable: configure endpoint, making it usable
1210  *
1211  * Check usb_ep_enable() at "usb_gadget.h" for details
1212  */
1213 static int ep_enable(struct usb_ep *ep,
1214 		     const struct usb_endpoint_descriptor *desc)
1215 {
1216 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1217 	int retval = 0;
1218 	unsigned long flags;
1219 	u32 cap = 0;
1220 
1221 	if (ep == NULL || desc == NULL)
1222 		return -EINVAL;
1223 
1224 	spin_lock_irqsave(hwep->lock, flags);
1225 
1226 	/* only internal SW should enable ctrl endpts */
1227 
1228 	if (!list_empty(&hwep->qh.queue)) {
1229 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1230 		spin_unlock_irqrestore(hwep->lock, flags);
1231 		return -EBUSY;
1232 	}
1233 
1234 	hwep->ep.desc = desc;
1235 
1236 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1237 	hwep->num  = usb_endpoint_num(desc);
1238 	hwep->type = usb_endpoint_type(desc);
1239 
1240 	hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1241 	hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1242 
1243 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1244 		cap |= QH_IOS;
1245 
1246 	cap |= QH_ZLT;
1247 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1248 	/*
1249 	 * For ISO-TX, we set mult at QH as the largest value, and use
1250 	 * MultO at TD as real mult value.
1251 	 */
1252 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1253 		cap |= 3 << __ffs(QH_MULT);
1254 
1255 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1256 
1257 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1258 
1259 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1260 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1261 		retval = -EINVAL;
1262 	}
1263 
1264 	/*
1265 	 * Enable endpoints in the HW other than ep0 as ep0
1266 	 * is always enabled
1267 	 */
1268 	if (hwep->num)
1269 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1270 				       hwep->type);
1271 
1272 	spin_unlock_irqrestore(hwep->lock, flags);
1273 	return retval;
1274 }
1275 
1276 /**
1277  * ep_disable: endpoint is no longer usable
1278  *
1279  * Check usb_ep_disable() at "usb_gadget.h" for details
1280  */
1281 static int ep_disable(struct usb_ep *ep)
1282 {
1283 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1284 	int direction, retval = 0;
1285 	unsigned long flags;
1286 
1287 	if (ep == NULL)
1288 		return -EINVAL;
1289 	else if (hwep->ep.desc == NULL)
1290 		return -EBUSY;
1291 
1292 	spin_lock_irqsave(hwep->lock, flags);
1293 
1294 	/* only internal SW should disable ctrl endpts */
1295 
1296 	direction = hwep->dir;
1297 	do {
1298 		retval |= _ep_nuke(hwep);
1299 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1300 
1301 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1302 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1303 
1304 	} while (hwep->dir != direction);
1305 
1306 	hwep->ep.desc = NULL;
1307 
1308 	spin_unlock_irqrestore(hwep->lock, flags);
1309 	return retval;
1310 }
1311 
1312 /**
1313  * ep_alloc_request: allocate a request object to use with this endpoint
1314  *
1315  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1316  */
1317 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1318 {
1319 	struct ci_hw_req *hwreq = NULL;
1320 
1321 	if (ep == NULL)
1322 		return NULL;
1323 
1324 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1325 	if (hwreq != NULL) {
1326 		INIT_LIST_HEAD(&hwreq->queue);
1327 		INIT_LIST_HEAD(&hwreq->tds);
1328 	}
1329 
1330 	return (hwreq == NULL) ? NULL : &hwreq->req;
1331 }
1332 
1333 /**
1334  * ep_free_request: frees a request object
1335  *
1336  * Check usb_ep_free_request() at "usb_gadget.h" for details
1337  */
1338 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1339 {
1340 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1341 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1342 	struct td_node *node, *tmpnode;
1343 	unsigned long flags;
1344 
1345 	if (ep == NULL || req == NULL) {
1346 		return;
1347 	} else if (!list_empty(&hwreq->queue)) {
1348 		dev_err(hwep->ci->dev, "freeing queued request\n");
1349 		return;
1350 	}
1351 
1352 	spin_lock_irqsave(hwep->lock, flags);
1353 
1354 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1355 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1356 		list_del_init(&node->td);
1357 		node->ptr = NULL;
1358 		kfree(node);
1359 	}
1360 
1361 	kfree(hwreq);
1362 
1363 	spin_unlock_irqrestore(hwep->lock, flags);
1364 }
1365 
1366 /**
1367  * ep_queue: queues (submits) an I/O request to an endpoint
1368  *
1369  * Check usb_ep_queue()* at usb_gadget.h" for details
1370  */
1371 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1372 		    gfp_t __maybe_unused gfp_flags)
1373 {
1374 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1375 	int retval = 0;
1376 	unsigned long flags;
1377 
1378 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1379 		return -EINVAL;
1380 
1381 	spin_lock_irqsave(hwep->lock, flags);
1382 	retval = _ep_queue(ep, req, gfp_flags);
1383 	spin_unlock_irqrestore(hwep->lock, flags);
1384 	return retval;
1385 }
1386 
1387 /**
1388  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1389  *
1390  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1391  */
1392 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1393 {
1394 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1395 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1396 	unsigned long flags;
1397 	struct td_node *node, *tmpnode;
1398 
1399 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1400 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1401 		list_empty(&hwep->qh.queue))
1402 		return -EINVAL;
1403 
1404 	spin_lock_irqsave(hwep->lock, flags);
1405 
1406 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1407 
1408 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1409 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1410 		list_del(&node->td);
1411 		kfree(node);
1412 	}
1413 
1414 	/* pop request */
1415 	list_del_init(&hwreq->queue);
1416 
1417 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1418 
1419 	req->status = -ECONNRESET;
1420 
1421 	if (hwreq->req.complete != NULL) {
1422 		spin_unlock(hwep->lock);
1423 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1424 		spin_lock(hwep->lock);
1425 	}
1426 
1427 	spin_unlock_irqrestore(hwep->lock, flags);
1428 	return 0;
1429 }
1430 
1431 /**
1432  * ep_set_halt: sets the endpoint halt feature
1433  *
1434  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1435  */
1436 static int ep_set_halt(struct usb_ep *ep, int value)
1437 {
1438 	return _ep_set_halt(ep, value, true);
1439 }
1440 
1441 /**
1442  * ep_set_wedge: sets the halt feature and ignores clear requests
1443  *
1444  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1445  */
1446 static int ep_set_wedge(struct usb_ep *ep)
1447 {
1448 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1449 	unsigned long flags;
1450 
1451 	if (ep == NULL || hwep->ep.desc == NULL)
1452 		return -EINVAL;
1453 
1454 	spin_lock_irqsave(hwep->lock, flags);
1455 	hwep->wedge = 1;
1456 	spin_unlock_irqrestore(hwep->lock, flags);
1457 
1458 	return usb_ep_set_halt(ep);
1459 }
1460 
1461 /**
1462  * ep_fifo_flush: flushes contents of a fifo
1463  *
1464  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1465  */
1466 static void ep_fifo_flush(struct usb_ep *ep)
1467 {
1468 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1469 	unsigned long flags;
1470 
1471 	if (ep == NULL) {
1472 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1473 		return;
1474 	}
1475 
1476 	spin_lock_irqsave(hwep->lock, flags);
1477 
1478 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1479 
1480 	spin_unlock_irqrestore(hwep->lock, flags);
1481 }
1482 
1483 /**
1484  * Endpoint-specific part of the API to the USB controller hardware
1485  * Check "usb_gadget.h" for details
1486  */
1487 static const struct usb_ep_ops usb_ep_ops = {
1488 	.enable	       = ep_enable,
1489 	.disable       = ep_disable,
1490 	.alloc_request = ep_alloc_request,
1491 	.free_request  = ep_free_request,
1492 	.queue	       = ep_queue,
1493 	.dequeue       = ep_dequeue,
1494 	.set_halt      = ep_set_halt,
1495 	.set_wedge     = ep_set_wedge,
1496 	.fifo_flush    = ep_fifo_flush,
1497 };
1498 
1499 /******************************************************************************
1500  * GADGET block
1501  *****************************************************************************/
1502 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1503 {
1504 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1505 	unsigned long flags;
1506 	int gadget_ready = 0;
1507 
1508 	spin_lock_irqsave(&ci->lock, flags);
1509 	ci->vbus_active = is_active;
1510 	if (ci->driver)
1511 		gadget_ready = 1;
1512 	spin_unlock_irqrestore(&ci->lock, flags);
1513 
1514 	if (gadget_ready) {
1515 		if (is_active) {
1516 			pm_runtime_get_sync(&_gadget->dev);
1517 			hw_device_reset(ci);
1518 			hw_device_state(ci, ci->ep0out->qh.dma);
1519 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1520 			usb_udc_vbus_handler(_gadget, true);
1521 		} else {
1522 			usb_udc_vbus_handler(_gadget, false);
1523 			if (ci->driver)
1524 				ci->driver->disconnect(&ci->gadget);
1525 			hw_device_state(ci, 0);
1526 			if (ci->platdata->notify_event)
1527 				ci->platdata->notify_event(ci,
1528 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1529 			_gadget_stop_activity(&ci->gadget);
1530 			pm_runtime_put_sync(&_gadget->dev);
1531 			usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1532 		}
1533 	}
1534 
1535 	return 0;
1536 }
1537 
1538 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1539 {
1540 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1541 	unsigned long flags;
1542 	int ret = 0;
1543 
1544 	spin_lock_irqsave(&ci->lock, flags);
1545 	if (!ci->remote_wakeup) {
1546 		ret = -EOPNOTSUPP;
1547 		goto out;
1548 	}
1549 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1550 		ret = -EINVAL;
1551 		goto out;
1552 	}
1553 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1554 out:
1555 	spin_unlock_irqrestore(&ci->lock, flags);
1556 	return ret;
1557 }
1558 
1559 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1560 {
1561 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1562 
1563 	if (ci->usb_phy)
1564 		return usb_phy_set_power(ci->usb_phy, ma);
1565 	return -ENOTSUPP;
1566 }
1567 
1568 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1569 {
1570 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1571 	struct ci_hw_ep *hwep = ci->ep0in;
1572 	unsigned long flags;
1573 
1574 	spin_lock_irqsave(hwep->lock, flags);
1575 	_gadget->is_selfpowered = (is_on != 0);
1576 	spin_unlock_irqrestore(hwep->lock, flags);
1577 
1578 	return 0;
1579 }
1580 
1581 /* Change Data+ pullup status
1582  * this func is used by usb_gadget_connect/disconnet
1583  */
1584 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1585 {
1586 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1587 
1588 	/* Data+ pullup controlled by OTG state machine in OTG fsm mode */
1589 	if (ci_otg_is_fsm_mode(ci))
1590 		return 0;
1591 
1592 	pm_runtime_get_sync(&ci->gadget.dev);
1593 	if (is_on)
1594 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1595 	else
1596 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1597 	pm_runtime_put_sync(&ci->gadget.dev);
1598 
1599 	return 0;
1600 }
1601 
1602 static int ci_udc_start(struct usb_gadget *gadget,
1603 			 struct usb_gadget_driver *driver);
1604 static int ci_udc_stop(struct usb_gadget *gadget);
1605 /**
1606  * Device operations part of the API to the USB controller hardware,
1607  * which don't involve endpoints (or i/o)
1608  * Check  "usb_gadget.h" for details
1609  */
1610 static const struct usb_gadget_ops usb_gadget_ops = {
1611 	.vbus_session	= ci_udc_vbus_session,
1612 	.wakeup		= ci_udc_wakeup,
1613 	.set_selfpowered	= ci_udc_selfpowered,
1614 	.pullup		= ci_udc_pullup,
1615 	.vbus_draw	= ci_udc_vbus_draw,
1616 	.udc_start	= ci_udc_start,
1617 	.udc_stop	= ci_udc_stop,
1618 };
1619 
1620 static int init_eps(struct ci_hdrc *ci)
1621 {
1622 	int retval = 0, i, j;
1623 
1624 	for (i = 0; i < ci->hw_ep_max/2; i++)
1625 		for (j = RX; j <= TX; j++) {
1626 			int k = i + j * ci->hw_ep_max/2;
1627 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1628 
1629 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1630 					(j == TX)  ? "in" : "out");
1631 
1632 			hwep->ci          = ci;
1633 			hwep->lock         = &ci->lock;
1634 			hwep->td_pool      = ci->td_pool;
1635 
1636 			hwep->ep.name      = hwep->name;
1637 			hwep->ep.ops       = &usb_ep_ops;
1638 
1639 			if (i == 0) {
1640 				hwep->ep.caps.type_control = true;
1641 			} else {
1642 				hwep->ep.caps.type_iso = true;
1643 				hwep->ep.caps.type_bulk = true;
1644 				hwep->ep.caps.type_int = true;
1645 			}
1646 
1647 			if (j == TX)
1648 				hwep->ep.caps.dir_in = true;
1649 			else
1650 				hwep->ep.caps.dir_out = true;
1651 
1652 			/*
1653 			 * for ep0: maxP defined in desc, for other
1654 			 * eps, maxP is set by epautoconfig() called
1655 			 * by gadget layer
1656 			 */
1657 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1658 
1659 			INIT_LIST_HEAD(&hwep->qh.queue);
1660 			hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1661 						     &hwep->qh.dma);
1662 			if (hwep->qh.ptr == NULL)
1663 				retval = -ENOMEM;
1664 			else
1665 				memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1666 
1667 			/*
1668 			 * set up shorthands for ep0 out and in endpoints,
1669 			 * don't add to gadget's ep_list
1670 			 */
1671 			if (i == 0) {
1672 				if (j == RX)
1673 					ci->ep0out = hwep;
1674 				else
1675 					ci->ep0in = hwep;
1676 
1677 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1678 				continue;
1679 			}
1680 
1681 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1682 		}
1683 
1684 	return retval;
1685 }
1686 
1687 static void destroy_eps(struct ci_hdrc *ci)
1688 {
1689 	int i;
1690 
1691 	for (i = 0; i < ci->hw_ep_max; i++) {
1692 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1693 
1694 		if (hwep->pending_td)
1695 			free_pending_td(hwep);
1696 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1697 	}
1698 }
1699 
1700 /**
1701  * ci_udc_start: register a gadget driver
1702  * @gadget: our gadget
1703  * @driver: the driver being registered
1704  *
1705  * Interrupts are enabled here.
1706  */
1707 static int ci_udc_start(struct usb_gadget *gadget,
1708 			 struct usb_gadget_driver *driver)
1709 {
1710 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1711 	unsigned long flags;
1712 	int retval = -ENOMEM;
1713 
1714 	if (driver->disconnect == NULL)
1715 		return -EINVAL;
1716 
1717 
1718 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1719 	retval = usb_ep_enable(&ci->ep0out->ep);
1720 	if (retval)
1721 		return retval;
1722 
1723 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1724 	retval = usb_ep_enable(&ci->ep0in->ep);
1725 	if (retval)
1726 		return retval;
1727 
1728 	ci->driver = driver;
1729 
1730 	/* Start otg fsm for B-device */
1731 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1732 		ci_hdrc_otg_fsm_start(ci);
1733 		return retval;
1734 	}
1735 
1736 	pm_runtime_get_sync(&ci->gadget.dev);
1737 	if (ci->vbus_active) {
1738 		spin_lock_irqsave(&ci->lock, flags);
1739 		hw_device_reset(ci);
1740 	} else {
1741 		usb_udc_vbus_handler(&ci->gadget, false);
1742 		pm_runtime_put_sync(&ci->gadget.dev);
1743 		return retval;
1744 	}
1745 
1746 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1747 	spin_unlock_irqrestore(&ci->lock, flags);
1748 	if (retval)
1749 		pm_runtime_put_sync(&ci->gadget.dev);
1750 
1751 	return retval;
1752 }
1753 
1754 /**
1755  * ci_udc_stop: unregister a gadget driver
1756  */
1757 static int ci_udc_stop(struct usb_gadget *gadget)
1758 {
1759 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1760 	unsigned long flags;
1761 
1762 	spin_lock_irqsave(&ci->lock, flags);
1763 
1764 	if (ci->vbus_active) {
1765 		hw_device_state(ci, 0);
1766 		if (ci->platdata->notify_event)
1767 			ci->platdata->notify_event(ci,
1768 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1769 		spin_unlock_irqrestore(&ci->lock, flags);
1770 		_gadget_stop_activity(&ci->gadget);
1771 		spin_lock_irqsave(&ci->lock, flags);
1772 		pm_runtime_put(&ci->gadget.dev);
1773 	}
1774 
1775 	ci->driver = NULL;
1776 	spin_unlock_irqrestore(&ci->lock, flags);
1777 
1778 	return 0;
1779 }
1780 
1781 /******************************************************************************
1782  * BUS block
1783  *****************************************************************************/
1784 /**
1785  * udc_irq: ci interrupt handler
1786  *
1787  * This function returns IRQ_HANDLED if the IRQ has been handled
1788  * It locks access to registers
1789  */
1790 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1791 {
1792 	irqreturn_t retval;
1793 	u32 intr;
1794 
1795 	if (ci == NULL)
1796 		return IRQ_HANDLED;
1797 
1798 	spin_lock(&ci->lock);
1799 
1800 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1801 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1802 				USBMODE_CM_DC) {
1803 			spin_unlock(&ci->lock);
1804 			return IRQ_NONE;
1805 		}
1806 	}
1807 	intr = hw_test_and_clear_intr_active(ci);
1808 
1809 	if (intr) {
1810 		/* order defines priority - do NOT change it */
1811 		if (USBi_URI & intr)
1812 			isr_reset_handler(ci);
1813 
1814 		if (USBi_PCI & intr) {
1815 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1816 				USB_SPEED_HIGH : USB_SPEED_FULL;
1817 			if (ci->suspended && ci->driver->resume) {
1818 				spin_unlock(&ci->lock);
1819 				ci->driver->resume(&ci->gadget);
1820 				spin_lock(&ci->lock);
1821 				ci->suspended = 0;
1822 			}
1823 		}
1824 
1825 		if (USBi_UI  & intr)
1826 			isr_tr_complete_handler(ci);
1827 
1828 		if (USBi_SLI & intr) {
1829 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1830 			    ci->driver->suspend) {
1831 				ci->suspended = 1;
1832 				spin_unlock(&ci->lock);
1833 				ci->driver->suspend(&ci->gadget);
1834 				usb_gadget_set_state(&ci->gadget,
1835 						USB_STATE_SUSPENDED);
1836 				spin_lock(&ci->lock);
1837 			}
1838 		}
1839 		retval = IRQ_HANDLED;
1840 	} else {
1841 		retval = IRQ_NONE;
1842 	}
1843 	spin_unlock(&ci->lock);
1844 
1845 	return retval;
1846 }
1847 
1848 /**
1849  * udc_start: initialize gadget role
1850  * @ci: chipidea controller
1851  */
1852 static int udc_start(struct ci_hdrc *ci)
1853 {
1854 	struct device *dev = ci->dev;
1855 	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
1856 	int retval = 0;
1857 
1858 	spin_lock_init(&ci->lock);
1859 
1860 	ci->gadget.ops          = &usb_gadget_ops;
1861 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1862 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1863 	ci->gadget.name         = ci->platdata->name;
1864 	ci->gadget.otg_caps	= otg_caps;
1865 
1866 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
1867 						otg_caps->adp_support))
1868 		ci->gadget.is_otg = 1;
1869 
1870 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1871 
1872 	/* alloc resources */
1873 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1874 				       sizeof(struct ci_hw_qh),
1875 				       64, CI_HDRC_PAGE_SIZE);
1876 	if (ci->qh_pool == NULL)
1877 		return -ENOMEM;
1878 
1879 	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1880 				       sizeof(struct ci_hw_td),
1881 				       64, CI_HDRC_PAGE_SIZE);
1882 	if (ci->td_pool == NULL) {
1883 		retval = -ENOMEM;
1884 		goto free_qh_pool;
1885 	}
1886 
1887 	retval = init_eps(ci);
1888 	if (retval)
1889 		goto free_pools;
1890 
1891 	ci->gadget.ep0 = &ci->ep0in->ep;
1892 
1893 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1894 	if (retval)
1895 		goto destroy_eps;
1896 
1897 	pm_runtime_no_callbacks(&ci->gadget.dev);
1898 	pm_runtime_enable(&ci->gadget.dev);
1899 
1900 	return retval;
1901 
1902 destroy_eps:
1903 	destroy_eps(ci);
1904 free_pools:
1905 	dma_pool_destroy(ci->td_pool);
1906 free_qh_pool:
1907 	dma_pool_destroy(ci->qh_pool);
1908 	return retval;
1909 }
1910 
1911 /**
1912  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1913  *
1914  * No interrupts active, the IRQ has been released
1915  */
1916 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1917 {
1918 	if (!ci->roles[CI_ROLE_GADGET])
1919 		return;
1920 
1921 	usb_del_gadget_udc(&ci->gadget);
1922 
1923 	destroy_eps(ci);
1924 
1925 	dma_pool_destroy(ci->td_pool);
1926 	dma_pool_destroy(ci->qh_pool);
1927 }
1928 
1929 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1930 {
1931 	if (ci->is_otg)
1932 		/* Clear and enable BSV irq */
1933 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
1934 					OTGSC_BSVIS | OTGSC_BSVIE);
1935 
1936 	return 0;
1937 }
1938 
1939 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1940 {
1941 	/*
1942 	 * host doesn't care B_SESSION_VALID event
1943 	 * so clear and disbale BSV irq
1944 	 */
1945 	if (ci->is_otg)
1946 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
1947 }
1948 
1949 /**
1950  * ci_hdrc_gadget_init - initialize device related bits
1951  * ci: the controller
1952  *
1953  * This function initializes the gadget, if the device is "device capable".
1954  */
1955 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1956 {
1957 	struct ci_role_driver *rdrv;
1958 
1959 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1960 		return -ENXIO;
1961 
1962 	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1963 	if (!rdrv)
1964 		return -ENOMEM;
1965 
1966 	rdrv->start	= udc_id_switch_for_device;
1967 	rdrv->stop	= udc_id_switch_for_host;
1968 	rdrv->irq	= udc_irq;
1969 	rdrv->name	= "gadget";
1970 	ci->roles[CI_ROLE_GADGET] = rdrv;
1971 
1972 	return udc_start(ci);
1973 }
1974