xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision a16be368)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * udc.c - ChipIdea UDC driver
4  *
5  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
6  *
7  * Author: David Lopo
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/dmapool.h>
13 #include <linux/err.h>
14 #include <linux/irqreturn.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/pinctrl/consumer.h>
19 #include <linux/usb/ch9.h>
20 #include <linux/usb/gadget.h>
21 #include <linux/usb/otg-fsm.h>
22 #include <linux/usb/chipidea.h>
23 
24 #include "ci.h"
25 #include "udc.h"
26 #include "bits.h"
27 #include "otg.h"
28 #include "otg_fsm.h"
29 
30 /* control endpoint description */
31 static const struct usb_endpoint_descriptor
32 ctrl_endpt_out_desc = {
33 	.bLength         = USB_DT_ENDPOINT_SIZE,
34 	.bDescriptorType = USB_DT_ENDPOINT,
35 
36 	.bEndpointAddress = USB_DIR_OUT,
37 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
38 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
39 };
40 
41 static const struct usb_endpoint_descriptor
42 ctrl_endpt_in_desc = {
43 	.bLength         = USB_DT_ENDPOINT_SIZE,
44 	.bDescriptorType = USB_DT_ENDPOINT,
45 
46 	.bEndpointAddress = USB_DIR_IN,
47 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
48 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
49 };
50 
51 /**
52  * hw_ep_bit: calculates the bit number
53  * @num: endpoint number
54  * @dir: endpoint direction
55  *
56  * This function returns bit number
57  */
58 static inline int hw_ep_bit(int num, int dir)
59 {
60 	return num + ((dir == TX) ? 16 : 0);
61 }
62 
63 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
64 {
65 	int fill = 16 - ci->hw_ep_max / 2;
66 
67 	if (n >= ci->hw_ep_max / 2)
68 		n += fill;
69 
70 	return n;
71 }
72 
73 /**
74  * hw_device_state: enables/disables interrupts (execute without interruption)
75  * @dma: 0 => disable, !0 => enable and set dma engine
76  *
77  * This function returns an error code
78  */
79 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
80 {
81 	if (dma) {
82 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
83 		/* interrupt, error, port change, reset, sleep/suspend */
84 		hw_write(ci, OP_USBINTR, ~0,
85 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
86 	} else {
87 		hw_write(ci, OP_USBINTR, ~0, 0);
88 	}
89 	return 0;
90 }
91 
92 /**
93  * hw_ep_flush: flush endpoint fifo (execute without interruption)
94  * @num: endpoint number
95  * @dir: endpoint direction
96  *
97  * This function returns an error code
98  */
99 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
100 {
101 	int n = hw_ep_bit(num, dir);
102 
103 	do {
104 		/* flush any pending transfer */
105 		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
106 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
107 			cpu_relax();
108 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
109 
110 	return 0;
111 }
112 
113 /**
114  * hw_ep_disable: disables endpoint (execute without interruption)
115  * @num: endpoint number
116  * @dir: endpoint direction
117  *
118  * This function returns an error code
119  */
120 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
121 {
122 	hw_write(ci, OP_ENDPTCTRL + num,
123 		 (dir == TX) ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
124 	return 0;
125 }
126 
127 /**
128  * hw_ep_enable: enables endpoint (execute without interruption)
129  * @num:  endpoint number
130  * @dir:  endpoint direction
131  * @type: endpoint type
132  *
133  * This function returns an error code
134  */
135 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
136 {
137 	u32 mask, data;
138 
139 	if (dir == TX) {
140 		mask  = ENDPTCTRL_TXT;  /* type    */
141 		data  = type << __ffs(mask);
142 
143 		mask |= ENDPTCTRL_TXS;  /* unstall */
144 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
145 		data |= ENDPTCTRL_TXR;
146 		mask |= ENDPTCTRL_TXE;  /* enable  */
147 		data |= ENDPTCTRL_TXE;
148 	} else {
149 		mask  = ENDPTCTRL_RXT;  /* type    */
150 		data  = type << __ffs(mask);
151 
152 		mask |= ENDPTCTRL_RXS;  /* unstall */
153 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
154 		data |= ENDPTCTRL_RXR;
155 		mask |= ENDPTCTRL_RXE;  /* enable  */
156 		data |= ENDPTCTRL_RXE;
157 	}
158 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
159 	return 0;
160 }
161 
162 /**
163  * hw_ep_get_halt: return endpoint halt status
164  * @num: endpoint number
165  * @dir: endpoint direction
166  *
167  * This function returns 1 if endpoint halted
168  */
169 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
170 {
171 	u32 mask = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
172 
173 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
174 }
175 
176 /**
177  * hw_ep_prime: primes endpoint (execute without interruption)
178  * @num:     endpoint number
179  * @dir:     endpoint direction
180  * @is_ctrl: true if control endpoint
181  *
182  * This function returns an error code
183  */
184 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
185 {
186 	int n = hw_ep_bit(num, dir);
187 
188 	/* Synchronize before ep prime */
189 	wmb();
190 
191 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
192 		return -EAGAIN;
193 
194 	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
195 
196 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
197 		cpu_relax();
198 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
199 		return -EAGAIN;
200 
201 	/* status shoult be tested according with manual but it doesn't work */
202 	return 0;
203 }
204 
205 /**
206  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
207  *                 without interruption)
208  * @num:   endpoint number
209  * @dir:   endpoint direction
210  * @value: true => stall, false => unstall
211  *
212  * This function returns an error code
213  */
214 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
215 {
216 	if (value != 0 && value != 1)
217 		return -EINVAL;
218 
219 	do {
220 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
221 		u32 mask_xs = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
222 		u32 mask_xr = (dir == TX) ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
223 
224 		/* data toggle - reserved for EP0 but it's in ESS */
225 		hw_write(ci, reg, mask_xs|mask_xr,
226 			  value ? mask_xs : mask_xr);
227 	} while (value != hw_ep_get_halt(ci, num, dir));
228 
229 	return 0;
230 }
231 
232 /**
233  * hw_is_port_high_speed: test if port is high speed
234  *
235  * This function returns true if high speed port
236  */
237 static int hw_port_is_high_speed(struct ci_hdrc *ci)
238 {
239 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
240 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
241 }
242 
243 /**
244  * hw_test_and_clear_complete: test & clear complete status (execute without
245  *                             interruption)
246  * @n: endpoint number
247  *
248  * This function returns complete status
249  */
250 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
251 {
252 	n = ep_to_bit(ci, n);
253 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
254 }
255 
256 /**
257  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
258  *                                without interruption)
259  *
260  * This function returns active interrutps
261  */
262 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
263 {
264 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
265 
266 	hw_write(ci, OP_USBSTS, ~0, reg);
267 	return reg;
268 }
269 
270 /**
271  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
272  *                                interruption)
273  *
274  * This function returns guard value
275  */
276 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
277 {
278 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
279 }
280 
281 /**
282  * hw_test_and_set_setup_guard: test & set setup guard (execute without
283  *                              interruption)
284  *
285  * This function returns guard value
286  */
287 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
288 {
289 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
290 }
291 
292 /**
293  * hw_usb_set_address: configures USB address (execute without interruption)
294  * @value: new USB address
295  *
296  * This function explicitly sets the address, without the "USBADRA" (advance)
297  * feature, which is not supported by older versions of the controller.
298  */
299 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
300 {
301 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
302 		 value << __ffs(DEVICEADDR_USBADR));
303 }
304 
305 /**
306  * hw_usb_reset: restart device after a bus reset (execute without
307  *               interruption)
308  *
309  * This function returns an error code
310  */
311 static int hw_usb_reset(struct ci_hdrc *ci)
312 {
313 	hw_usb_set_address(ci, 0);
314 
315 	/* ESS flushes only at end?!? */
316 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
317 
318 	/* clear setup token semaphores */
319 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
320 
321 	/* clear complete status */
322 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
323 
324 	/* wait until all bits cleared */
325 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
326 		udelay(10);             /* not RTOS friendly */
327 
328 	/* reset all endpoints ? */
329 
330 	/* reset internal status and wait for further instructions
331 	   no need to verify the port reset status (ESS does it) */
332 
333 	return 0;
334 }
335 
336 /******************************************************************************
337  * UTIL block
338  *****************************************************************************/
339 
340 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
341 			unsigned int length, struct scatterlist *s)
342 {
343 	int i;
344 	u32 temp;
345 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
346 						  GFP_ATOMIC);
347 
348 	if (node == NULL)
349 		return -ENOMEM;
350 
351 	node->ptr = dma_pool_zalloc(hwep->td_pool, GFP_ATOMIC, &node->dma);
352 	if (node->ptr == NULL) {
353 		kfree(node);
354 		return -ENOMEM;
355 	}
356 
357 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
358 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
359 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
360 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
361 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
362 
363 		if (hwreq->req.length == 0
364 				|| hwreq->req.length % hwep->ep.maxpacket)
365 			mul++;
366 		node->ptr->token |= cpu_to_le32(mul << __ffs(TD_MULTO));
367 	}
368 
369 	if (s) {
370 		temp = (u32) (sg_dma_address(s) + hwreq->req.actual);
371 		node->td_remaining_size = CI_MAX_BUF_SIZE - length;
372 	} else {
373 		temp = (u32) (hwreq->req.dma + hwreq->req.actual);
374 	}
375 
376 	if (length) {
377 		node->ptr->page[0] = cpu_to_le32(temp);
378 		for (i = 1; i < TD_PAGE_COUNT; i++) {
379 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
380 			page &= ~TD_RESERVED_MASK;
381 			node->ptr->page[i] = cpu_to_le32(page);
382 		}
383 	}
384 
385 	hwreq->req.actual += length;
386 
387 	if (!list_empty(&hwreq->tds)) {
388 		/* get the last entry */
389 		lastnode = list_entry(hwreq->tds.prev,
390 				struct td_node, td);
391 		lastnode->ptr->next = cpu_to_le32(node->dma);
392 	}
393 
394 	INIT_LIST_HEAD(&node->td);
395 	list_add_tail(&node->td, &hwreq->tds);
396 
397 	return 0;
398 }
399 
400 /**
401  * _usb_addr: calculates endpoint address from direction & number
402  * @ep:  endpoint
403  */
404 static inline u8 _usb_addr(struct ci_hw_ep *ep)
405 {
406 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
407 }
408 
409 static int prepare_td_for_non_sg(struct ci_hw_ep *hwep,
410 		struct ci_hw_req *hwreq)
411 {
412 	unsigned int rest = hwreq->req.length;
413 	int pages = TD_PAGE_COUNT;
414 	int ret = 0;
415 
416 	if (rest == 0) {
417 		ret = add_td_to_list(hwep, hwreq, 0, NULL);
418 		if (ret < 0)
419 			return ret;
420 	}
421 
422 	/*
423 	 * The first buffer could be not page aligned.
424 	 * In that case we have to span into one extra td.
425 	 */
426 	if (hwreq->req.dma % PAGE_SIZE)
427 		pages--;
428 
429 	while (rest > 0) {
430 		unsigned int count = min(hwreq->req.length - hwreq->req.actual,
431 			(unsigned int)(pages * CI_HDRC_PAGE_SIZE));
432 
433 		ret = add_td_to_list(hwep, hwreq, count, NULL);
434 		if (ret < 0)
435 			return ret;
436 
437 		rest -= count;
438 	}
439 
440 	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
441 	    && (hwreq->req.length % hwep->ep.maxpacket == 0)) {
442 		ret = add_td_to_list(hwep, hwreq, 0, NULL);
443 		if (ret < 0)
444 			return ret;
445 	}
446 
447 	return ret;
448 }
449 
450 static int prepare_td_per_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
451 		struct scatterlist *s)
452 {
453 	unsigned int rest = sg_dma_len(s);
454 	int ret = 0;
455 
456 	hwreq->req.actual = 0;
457 	while (rest > 0) {
458 		unsigned int count = min_t(unsigned int, rest,
459 				CI_MAX_BUF_SIZE);
460 
461 		ret = add_td_to_list(hwep, hwreq, count, s);
462 		if (ret < 0)
463 			return ret;
464 
465 		rest -= count;
466 	}
467 
468 	return ret;
469 }
470 
471 static void ci_add_buffer_entry(struct td_node *node, struct scatterlist *s)
472 {
473 	int empty_td_slot_index = (CI_MAX_BUF_SIZE - node->td_remaining_size)
474 			/ CI_HDRC_PAGE_SIZE;
475 	int i;
476 
477 	node->ptr->token +=
478 		cpu_to_le32(sg_dma_len(s) << __ffs(TD_TOTAL_BYTES));
479 
480 	for (i = empty_td_slot_index; i < TD_PAGE_COUNT; i++) {
481 		u32 page = (u32) sg_dma_address(s) +
482 			(i - empty_td_slot_index) * CI_HDRC_PAGE_SIZE;
483 
484 		page &= ~TD_RESERVED_MASK;
485 		node->ptr->page[i] = cpu_to_le32(page);
486 	}
487 }
488 
489 static int prepare_td_for_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
490 {
491 	struct usb_request *req = &hwreq->req;
492 	struct scatterlist *s = req->sg;
493 	int ret = 0, i = 0;
494 	struct td_node *node = NULL;
495 
496 	if (!s || req->zero || req->length == 0) {
497 		dev_err(hwep->ci->dev, "not supported operation for sg\n");
498 		return -EINVAL;
499 	}
500 
501 	while (i++ < req->num_mapped_sgs) {
502 		if (sg_dma_address(s) % PAGE_SIZE) {
503 			dev_err(hwep->ci->dev, "not page aligned sg buffer\n");
504 			return -EINVAL;
505 		}
506 
507 		if (node && (node->td_remaining_size >= sg_dma_len(s))) {
508 			ci_add_buffer_entry(node, s);
509 			node->td_remaining_size -= sg_dma_len(s);
510 		} else {
511 			ret = prepare_td_per_sg(hwep, hwreq, s);
512 			if (ret)
513 				return ret;
514 
515 			node = list_entry(hwreq->tds.prev,
516 				struct td_node, td);
517 		}
518 
519 		s = sg_next(s);
520 	}
521 
522 	return ret;
523 }
524 
525 /**
526  * _hardware_enqueue: configures a request at hardware level
527  * @hwep:   endpoint
528  * @hwreq:  request
529  *
530  * This function returns an error code
531  */
532 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
533 {
534 	struct ci_hdrc *ci = hwep->ci;
535 	int ret = 0;
536 	struct td_node *firstnode, *lastnode;
537 
538 	/* don't queue twice */
539 	if (hwreq->req.status == -EALREADY)
540 		return -EALREADY;
541 
542 	hwreq->req.status = -EALREADY;
543 
544 	ret = usb_gadget_map_request_by_dev(ci->dev->parent,
545 					    &hwreq->req, hwep->dir);
546 	if (ret)
547 		return ret;
548 
549 	if (hwreq->req.num_mapped_sgs)
550 		ret = prepare_td_for_sg(hwep, hwreq);
551 	else
552 		ret = prepare_td_for_non_sg(hwep, hwreq);
553 
554 	if (ret)
555 		return ret;
556 
557 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
558 
559 	lastnode = list_entry(hwreq->tds.prev,
560 		struct td_node, td);
561 
562 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
563 	if (!hwreq->req.no_interrupt)
564 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
565 	wmb();
566 
567 	hwreq->req.actual = 0;
568 	if (!list_empty(&hwep->qh.queue)) {
569 		struct ci_hw_req *hwreqprev;
570 		int n = hw_ep_bit(hwep->num, hwep->dir);
571 		int tmp_stat;
572 		struct td_node *prevlastnode;
573 		u32 next = firstnode->dma & TD_ADDR_MASK;
574 
575 		hwreqprev = list_entry(hwep->qh.queue.prev,
576 				struct ci_hw_req, queue);
577 		prevlastnode = list_entry(hwreqprev->tds.prev,
578 				struct td_node, td);
579 
580 		prevlastnode->ptr->next = cpu_to_le32(next);
581 		wmb();
582 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
583 			goto done;
584 		do {
585 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
586 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
587 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
588 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
589 		if (tmp_stat)
590 			goto done;
591 	}
592 
593 	/*  QH configuration */
594 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
595 	hwep->qh.ptr->td.token &=
596 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
597 
598 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
599 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
600 
601 		if (hwreq->req.length == 0
602 				|| hwreq->req.length % hwep->ep.maxpacket)
603 			mul++;
604 		hwep->qh.ptr->cap |= cpu_to_le32(mul << __ffs(QH_MULT));
605 	}
606 
607 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
608 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
609 done:
610 	return ret;
611 }
612 
613 /*
614  * free_pending_td: remove a pending request for the endpoint
615  * @hwep: endpoint
616  */
617 static void free_pending_td(struct ci_hw_ep *hwep)
618 {
619 	struct td_node *pending = hwep->pending_td;
620 
621 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
622 	hwep->pending_td = NULL;
623 	kfree(pending);
624 }
625 
626 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
627 					   struct td_node *node)
628 {
629 	hwep->qh.ptr->td.next = cpu_to_le32(node->dma);
630 	hwep->qh.ptr->td.token &=
631 		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
632 
633 	return hw_ep_prime(ci, hwep->num, hwep->dir,
634 				hwep->type == USB_ENDPOINT_XFER_CONTROL);
635 }
636 
637 /**
638  * _hardware_dequeue: handles a request at hardware level
639  * @gadget: gadget
640  * @hwep:   endpoint
641  *
642  * This function returns an error code
643  */
644 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
645 {
646 	u32 tmptoken;
647 	struct td_node *node, *tmpnode;
648 	unsigned remaining_length;
649 	unsigned actual = hwreq->req.length;
650 	struct ci_hdrc *ci = hwep->ci;
651 
652 	if (hwreq->req.status != -EALREADY)
653 		return -EINVAL;
654 
655 	hwreq->req.status = 0;
656 
657 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
658 		tmptoken = le32_to_cpu(node->ptr->token);
659 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
660 			int n = hw_ep_bit(hwep->num, hwep->dir);
661 
662 			if (ci->rev == CI_REVISION_24)
663 				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
664 					reprime_dtd(ci, hwep, node);
665 			hwreq->req.status = -EALREADY;
666 			return -EBUSY;
667 		}
668 
669 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
670 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
671 		actual -= remaining_length;
672 
673 		hwreq->req.status = tmptoken & TD_STATUS;
674 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
675 			hwreq->req.status = -EPIPE;
676 			break;
677 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
678 			hwreq->req.status = -EPROTO;
679 			break;
680 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
681 			hwreq->req.status = -EILSEQ;
682 			break;
683 		}
684 
685 		if (remaining_length) {
686 			if (hwep->dir == TX) {
687 				hwreq->req.status = -EPROTO;
688 				break;
689 			}
690 		}
691 		/*
692 		 * As the hardware could still address the freed td
693 		 * which will run the udc unusable, the cleanup of the
694 		 * td has to be delayed by one.
695 		 */
696 		if (hwep->pending_td)
697 			free_pending_td(hwep);
698 
699 		hwep->pending_td = node;
700 		list_del_init(&node->td);
701 	}
702 
703 	usb_gadget_unmap_request_by_dev(hwep->ci->dev->parent,
704 					&hwreq->req, hwep->dir);
705 
706 	hwreq->req.actual += actual;
707 
708 	if (hwreq->req.status)
709 		return hwreq->req.status;
710 
711 	return hwreq->req.actual;
712 }
713 
714 /**
715  * _ep_nuke: dequeues all endpoint requests
716  * @hwep: endpoint
717  *
718  * This function returns an error code
719  * Caller must hold lock
720  */
721 static int _ep_nuke(struct ci_hw_ep *hwep)
722 __releases(hwep->lock)
723 __acquires(hwep->lock)
724 {
725 	struct td_node *node, *tmpnode;
726 	if (hwep == NULL)
727 		return -EINVAL;
728 
729 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
730 
731 	while (!list_empty(&hwep->qh.queue)) {
732 
733 		/* pop oldest request */
734 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
735 						     struct ci_hw_req, queue);
736 
737 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
738 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
739 			list_del_init(&node->td);
740 			node->ptr = NULL;
741 			kfree(node);
742 		}
743 
744 		list_del_init(&hwreq->queue);
745 		hwreq->req.status = -ESHUTDOWN;
746 
747 		if (hwreq->req.complete != NULL) {
748 			spin_unlock(hwep->lock);
749 			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
750 			spin_lock(hwep->lock);
751 		}
752 	}
753 
754 	if (hwep->pending_td)
755 		free_pending_td(hwep);
756 
757 	return 0;
758 }
759 
760 static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
761 {
762 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
763 	int direction, retval = 0;
764 	unsigned long flags;
765 
766 	if (ep == NULL || hwep->ep.desc == NULL)
767 		return -EINVAL;
768 
769 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
770 		return -EOPNOTSUPP;
771 
772 	spin_lock_irqsave(hwep->lock, flags);
773 
774 	if (value && hwep->dir == TX && check_transfer &&
775 		!list_empty(&hwep->qh.queue) &&
776 			!usb_endpoint_xfer_control(hwep->ep.desc)) {
777 		spin_unlock_irqrestore(hwep->lock, flags);
778 		return -EAGAIN;
779 	}
780 
781 	direction = hwep->dir;
782 	do {
783 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
784 
785 		if (!value)
786 			hwep->wedge = 0;
787 
788 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
789 			hwep->dir = (hwep->dir == TX) ? RX : TX;
790 
791 	} while (hwep->dir != direction);
792 
793 	spin_unlock_irqrestore(hwep->lock, flags);
794 	return retval;
795 }
796 
797 
798 /**
799  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
800  * @gadget: gadget
801  *
802  * This function returns an error code
803  */
804 static int _gadget_stop_activity(struct usb_gadget *gadget)
805 {
806 	struct usb_ep *ep;
807 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
808 	unsigned long flags;
809 
810 	/* flush all endpoints */
811 	gadget_for_each_ep(ep, gadget) {
812 		usb_ep_fifo_flush(ep);
813 	}
814 	usb_ep_fifo_flush(&ci->ep0out->ep);
815 	usb_ep_fifo_flush(&ci->ep0in->ep);
816 
817 	/* make sure to disable all endpoints */
818 	gadget_for_each_ep(ep, gadget) {
819 		usb_ep_disable(ep);
820 	}
821 
822 	if (ci->status != NULL) {
823 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
824 		ci->status = NULL;
825 	}
826 
827 	spin_lock_irqsave(&ci->lock, flags);
828 	ci->gadget.speed = USB_SPEED_UNKNOWN;
829 	ci->remote_wakeup = 0;
830 	ci->suspended = 0;
831 	spin_unlock_irqrestore(&ci->lock, flags);
832 
833 	return 0;
834 }
835 
836 /******************************************************************************
837  * ISR block
838  *****************************************************************************/
839 /**
840  * isr_reset_handler: USB reset interrupt handler
841  * @ci: UDC device
842  *
843  * This function resets USB engine after a bus reset occurred
844  */
845 static void isr_reset_handler(struct ci_hdrc *ci)
846 __releases(ci->lock)
847 __acquires(ci->lock)
848 {
849 	int retval;
850 
851 	spin_unlock(&ci->lock);
852 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
853 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
854 
855 	retval = _gadget_stop_activity(&ci->gadget);
856 	if (retval)
857 		goto done;
858 
859 	retval = hw_usb_reset(ci);
860 	if (retval)
861 		goto done;
862 
863 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
864 	if (ci->status == NULL)
865 		retval = -ENOMEM;
866 
867 done:
868 	spin_lock(&ci->lock);
869 
870 	if (retval)
871 		dev_err(ci->dev, "error: %i\n", retval);
872 }
873 
874 /**
875  * isr_get_status_complete: get_status request complete function
876  * @ep:  endpoint
877  * @req: request handled
878  *
879  * Caller must release lock
880  */
881 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
882 {
883 	if (ep == NULL || req == NULL)
884 		return;
885 
886 	kfree(req->buf);
887 	usb_ep_free_request(ep, req);
888 }
889 
890 /**
891  * _ep_queue: queues (submits) an I/O request to an endpoint
892  * @ep:        endpoint
893  * @req:       request
894  * @gfp_flags: GFP flags (not used)
895  *
896  * Caller must hold lock
897  * This function returns an error code
898  */
899 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
900 		    gfp_t __maybe_unused gfp_flags)
901 {
902 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
903 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
904 	struct ci_hdrc *ci = hwep->ci;
905 	int retval = 0;
906 
907 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
908 		return -EINVAL;
909 
910 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
911 		if (req->length)
912 			hwep = (ci->ep0_dir == RX) ?
913 			       ci->ep0out : ci->ep0in;
914 		if (!list_empty(&hwep->qh.queue)) {
915 			_ep_nuke(hwep);
916 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
917 				 _usb_addr(hwep));
918 		}
919 	}
920 
921 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
922 	    hwreq->req.length > hwep->ep.mult * hwep->ep.maxpacket) {
923 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
924 		return -EMSGSIZE;
925 	}
926 
927 	/* first nuke then test link, e.g. previous status has not sent */
928 	if (!list_empty(&hwreq->queue)) {
929 		dev_err(hwep->ci->dev, "request already in queue\n");
930 		return -EBUSY;
931 	}
932 
933 	/* push request */
934 	hwreq->req.status = -EINPROGRESS;
935 	hwreq->req.actual = 0;
936 
937 	retval = _hardware_enqueue(hwep, hwreq);
938 
939 	if (retval == -EALREADY)
940 		retval = 0;
941 	if (!retval)
942 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
943 
944 	return retval;
945 }
946 
947 /**
948  * isr_get_status_response: get_status request response
949  * @ci: ci struct
950  * @setup: setup request packet
951  *
952  * This function returns an error code
953  */
954 static int isr_get_status_response(struct ci_hdrc *ci,
955 				   struct usb_ctrlrequest *setup)
956 __releases(hwep->lock)
957 __acquires(hwep->lock)
958 {
959 	struct ci_hw_ep *hwep = ci->ep0in;
960 	struct usb_request *req = NULL;
961 	gfp_t gfp_flags = GFP_ATOMIC;
962 	int dir, num, retval;
963 
964 	if (hwep == NULL || setup == NULL)
965 		return -EINVAL;
966 
967 	spin_unlock(hwep->lock);
968 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
969 	spin_lock(hwep->lock);
970 	if (req == NULL)
971 		return -ENOMEM;
972 
973 	req->complete = isr_get_status_complete;
974 	req->length   = 2;
975 	req->buf      = kzalloc(req->length, gfp_flags);
976 	if (req->buf == NULL) {
977 		retval = -ENOMEM;
978 		goto err_free_req;
979 	}
980 
981 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
982 		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
983 			ci->gadget.is_selfpowered;
984 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
985 		   == USB_RECIP_ENDPOINT) {
986 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
987 			TX : RX;
988 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
989 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
990 	}
991 	/* else do nothing; reserved for future use */
992 
993 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
994 	if (retval)
995 		goto err_free_buf;
996 
997 	return 0;
998 
999  err_free_buf:
1000 	kfree(req->buf);
1001  err_free_req:
1002 	spin_unlock(hwep->lock);
1003 	usb_ep_free_request(&hwep->ep, req);
1004 	spin_lock(hwep->lock);
1005 	return retval;
1006 }
1007 
1008 /**
1009  * isr_setup_status_complete: setup_status request complete function
1010  * @ep:  endpoint
1011  * @req: request handled
1012  *
1013  * Caller must release lock. Put the port in test mode if test mode
1014  * feature is selected.
1015  */
1016 static void
1017 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
1018 {
1019 	struct ci_hdrc *ci = req->context;
1020 	unsigned long flags;
1021 
1022 	if (ci->setaddr) {
1023 		hw_usb_set_address(ci, ci->address);
1024 		ci->setaddr = false;
1025 		if (ci->address)
1026 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
1027 	}
1028 
1029 	spin_lock_irqsave(&ci->lock, flags);
1030 	if (ci->test_mode)
1031 		hw_port_test_set(ci, ci->test_mode);
1032 	spin_unlock_irqrestore(&ci->lock, flags);
1033 }
1034 
1035 /**
1036  * isr_setup_status_phase: queues the status phase of a setup transation
1037  * @ci: ci struct
1038  *
1039  * This function returns an error code
1040  */
1041 static int isr_setup_status_phase(struct ci_hdrc *ci)
1042 {
1043 	struct ci_hw_ep *hwep;
1044 
1045 	/*
1046 	 * Unexpected USB controller behavior, caused by bad signal integrity
1047 	 * or ground reference problems, can lead to isr_setup_status_phase
1048 	 * being called with ci->status equal to NULL.
1049 	 * If this situation occurs, you should review your USB hardware design.
1050 	 */
1051 	if (WARN_ON_ONCE(!ci->status))
1052 		return -EPIPE;
1053 
1054 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
1055 	ci->status->context = ci;
1056 	ci->status->complete = isr_setup_status_complete;
1057 
1058 	return _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
1059 }
1060 
1061 /**
1062  * isr_tr_complete_low: transaction complete low level handler
1063  * @hwep: endpoint
1064  *
1065  * This function returns an error code
1066  * Caller must hold lock
1067  */
1068 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
1069 __releases(hwep->lock)
1070 __acquires(hwep->lock)
1071 {
1072 	struct ci_hw_req *hwreq, *hwreqtemp;
1073 	struct ci_hw_ep *hweptemp = hwep;
1074 	int retval = 0;
1075 
1076 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
1077 			queue) {
1078 		retval = _hardware_dequeue(hwep, hwreq);
1079 		if (retval < 0)
1080 			break;
1081 		list_del_init(&hwreq->queue);
1082 		if (hwreq->req.complete != NULL) {
1083 			spin_unlock(hwep->lock);
1084 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
1085 					hwreq->req.length)
1086 				hweptemp = hwep->ci->ep0in;
1087 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
1088 			spin_lock(hwep->lock);
1089 		}
1090 	}
1091 
1092 	if (retval == -EBUSY)
1093 		retval = 0;
1094 
1095 	return retval;
1096 }
1097 
1098 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
1099 {
1100 	dev_warn(&ci->gadget.dev,
1101 		"connect the device to an alternate port if you want HNP\n");
1102 	return isr_setup_status_phase(ci);
1103 }
1104 
1105 /**
1106  * isr_setup_packet_handler: setup packet handler
1107  * @ci: UDC descriptor
1108  *
1109  * This function handles setup packet
1110  */
1111 static void isr_setup_packet_handler(struct ci_hdrc *ci)
1112 __releases(ci->lock)
1113 __acquires(ci->lock)
1114 {
1115 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1116 	struct usb_ctrlrequest req;
1117 	int type, num, dir, err = -EINVAL;
1118 	u8 tmode = 0;
1119 
1120 	/*
1121 	 * Flush data and handshake transactions of previous
1122 	 * setup packet.
1123 	 */
1124 	_ep_nuke(ci->ep0out);
1125 	_ep_nuke(ci->ep0in);
1126 
1127 	/* read_setup_packet */
1128 	do {
1129 		hw_test_and_set_setup_guard(ci);
1130 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1131 	} while (!hw_test_and_clear_setup_guard(ci));
1132 
1133 	type = req.bRequestType;
1134 
1135 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1136 
1137 	switch (req.bRequest) {
1138 	case USB_REQ_CLEAR_FEATURE:
1139 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1140 				le16_to_cpu(req.wValue) ==
1141 				USB_ENDPOINT_HALT) {
1142 			if (req.wLength != 0)
1143 				break;
1144 			num  = le16_to_cpu(req.wIndex);
1145 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1146 			num &= USB_ENDPOINT_NUMBER_MASK;
1147 			if (dir == TX)
1148 				num += ci->hw_ep_max / 2;
1149 			if (!ci->ci_hw_ep[num].wedge) {
1150 				spin_unlock(&ci->lock);
1151 				err = usb_ep_clear_halt(
1152 					&ci->ci_hw_ep[num].ep);
1153 				spin_lock(&ci->lock);
1154 				if (err)
1155 					break;
1156 			}
1157 			err = isr_setup_status_phase(ci);
1158 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1159 				le16_to_cpu(req.wValue) ==
1160 				USB_DEVICE_REMOTE_WAKEUP) {
1161 			if (req.wLength != 0)
1162 				break;
1163 			ci->remote_wakeup = 0;
1164 			err = isr_setup_status_phase(ci);
1165 		} else {
1166 			goto delegate;
1167 		}
1168 		break;
1169 	case USB_REQ_GET_STATUS:
1170 		if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
1171 			le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
1172 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1173 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1174 			goto delegate;
1175 		if (le16_to_cpu(req.wLength) != 2 ||
1176 		    le16_to_cpu(req.wValue)  != 0)
1177 			break;
1178 		err = isr_get_status_response(ci, &req);
1179 		break;
1180 	case USB_REQ_SET_ADDRESS:
1181 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1182 			goto delegate;
1183 		if (le16_to_cpu(req.wLength) != 0 ||
1184 		    le16_to_cpu(req.wIndex)  != 0)
1185 			break;
1186 		ci->address = (u8)le16_to_cpu(req.wValue);
1187 		ci->setaddr = true;
1188 		err = isr_setup_status_phase(ci);
1189 		break;
1190 	case USB_REQ_SET_FEATURE:
1191 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1192 				le16_to_cpu(req.wValue) ==
1193 				USB_ENDPOINT_HALT) {
1194 			if (req.wLength != 0)
1195 				break;
1196 			num  = le16_to_cpu(req.wIndex);
1197 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1198 			num &= USB_ENDPOINT_NUMBER_MASK;
1199 			if (dir == TX)
1200 				num += ci->hw_ep_max / 2;
1201 
1202 			spin_unlock(&ci->lock);
1203 			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1204 			spin_lock(&ci->lock);
1205 			if (!err)
1206 				isr_setup_status_phase(ci);
1207 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1208 			if (req.wLength != 0)
1209 				break;
1210 			switch (le16_to_cpu(req.wValue)) {
1211 			case USB_DEVICE_REMOTE_WAKEUP:
1212 				ci->remote_wakeup = 1;
1213 				err = isr_setup_status_phase(ci);
1214 				break;
1215 			case USB_DEVICE_TEST_MODE:
1216 				tmode = le16_to_cpu(req.wIndex) >> 8;
1217 				switch (tmode) {
1218 				case TEST_J:
1219 				case TEST_K:
1220 				case TEST_SE0_NAK:
1221 				case TEST_PACKET:
1222 				case TEST_FORCE_EN:
1223 					ci->test_mode = tmode;
1224 					err = isr_setup_status_phase(
1225 							ci);
1226 					break;
1227 				default:
1228 					break;
1229 				}
1230 				break;
1231 			case USB_DEVICE_B_HNP_ENABLE:
1232 				if (ci_otg_is_fsm_mode(ci)) {
1233 					ci->gadget.b_hnp_enable = 1;
1234 					err = isr_setup_status_phase(
1235 							ci);
1236 				}
1237 				break;
1238 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1239 				if (ci_otg_is_fsm_mode(ci))
1240 					err = otg_a_alt_hnp_support(ci);
1241 				break;
1242 			case USB_DEVICE_A_HNP_SUPPORT:
1243 				if (ci_otg_is_fsm_mode(ci)) {
1244 					ci->gadget.a_hnp_support = 1;
1245 					err = isr_setup_status_phase(
1246 							ci);
1247 				}
1248 				break;
1249 			default:
1250 				goto delegate;
1251 			}
1252 		} else {
1253 			goto delegate;
1254 		}
1255 		break;
1256 	default:
1257 delegate:
1258 		if (req.wLength == 0)   /* no data phase */
1259 			ci->ep0_dir = TX;
1260 
1261 		spin_unlock(&ci->lock);
1262 		err = ci->driver->setup(&ci->gadget, &req);
1263 		spin_lock(&ci->lock);
1264 		break;
1265 	}
1266 
1267 	if (err < 0) {
1268 		spin_unlock(&ci->lock);
1269 		if (_ep_set_halt(&hwep->ep, 1, false))
1270 			dev_err(ci->dev, "error: _ep_set_halt\n");
1271 		spin_lock(&ci->lock);
1272 	}
1273 }
1274 
1275 /**
1276  * isr_tr_complete_handler: transaction complete interrupt handler
1277  * @ci: UDC descriptor
1278  *
1279  * This function handles traffic events
1280  */
1281 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1282 __releases(ci->lock)
1283 __acquires(ci->lock)
1284 {
1285 	unsigned i;
1286 	int err;
1287 
1288 	for (i = 0; i < ci->hw_ep_max; i++) {
1289 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1290 
1291 		if (hwep->ep.desc == NULL)
1292 			continue;   /* not configured */
1293 
1294 		if (hw_test_and_clear_complete(ci, i)) {
1295 			err = isr_tr_complete_low(hwep);
1296 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1297 				if (err > 0)   /* needs status phase */
1298 					err = isr_setup_status_phase(ci);
1299 				if (err < 0) {
1300 					spin_unlock(&ci->lock);
1301 					if (_ep_set_halt(&hwep->ep, 1, false))
1302 						dev_err(ci->dev,
1303 						"error: _ep_set_halt\n");
1304 					spin_lock(&ci->lock);
1305 				}
1306 			}
1307 		}
1308 
1309 		/* Only handle setup packet below */
1310 		if (i == 0 &&
1311 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1312 			isr_setup_packet_handler(ci);
1313 	}
1314 }
1315 
1316 /******************************************************************************
1317  * ENDPT block
1318  *****************************************************************************/
1319 /**
1320  * ep_enable: configure endpoint, making it usable
1321  *
1322  * Check usb_ep_enable() at "usb_gadget.h" for details
1323  */
1324 static int ep_enable(struct usb_ep *ep,
1325 		     const struct usb_endpoint_descriptor *desc)
1326 {
1327 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1328 	int retval = 0;
1329 	unsigned long flags;
1330 	u32 cap = 0;
1331 
1332 	if (ep == NULL || desc == NULL)
1333 		return -EINVAL;
1334 
1335 	spin_lock_irqsave(hwep->lock, flags);
1336 
1337 	/* only internal SW should enable ctrl endpts */
1338 
1339 	if (!list_empty(&hwep->qh.queue)) {
1340 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1341 		spin_unlock_irqrestore(hwep->lock, flags);
1342 		return -EBUSY;
1343 	}
1344 
1345 	hwep->ep.desc = desc;
1346 
1347 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1348 	hwep->num  = usb_endpoint_num(desc);
1349 	hwep->type = usb_endpoint_type(desc);
1350 
1351 	hwep->ep.maxpacket = usb_endpoint_maxp(desc);
1352 	hwep->ep.mult = usb_endpoint_maxp_mult(desc);
1353 
1354 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1355 		cap |= QH_IOS;
1356 
1357 	cap |= QH_ZLT;
1358 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1359 	/*
1360 	 * For ISO-TX, we set mult at QH as the largest value, and use
1361 	 * MultO at TD as real mult value.
1362 	 */
1363 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1364 		cap |= 3 << __ffs(QH_MULT);
1365 
1366 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1367 
1368 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1369 
1370 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1371 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1372 		retval = -EINVAL;
1373 	}
1374 
1375 	/*
1376 	 * Enable endpoints in the HW other than ep0 as ep0
1377 	 * is always enabled
1378 	 */
1379 	if (hwep->num)
1380 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1381 				       hwep->type);
1382 
1383 	spin_unlock_irqrestore(hwep->lock, flags);
1384 	return retval;
1385 }
1386 
1387 /**
1388  * ep_disable: endpoint is no longer usable
1389  *
1390  * Check usb_ep_disable() at "usb_gadget.h" for details
1391  */
1392 static int ep_disable(struct usb_ep *ep)
1393 {
1394 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1395 	int direction, retval = 0;
1396 	unsigned long flags;
1397 
1398 	if (ep == NULL)
1399 		return -EINVAL;
1400 	else if (hwep->ep.desc == NULL)
1401 		return -EBUSY;
1402 
1403 	spin_lock_irqsave(hwep->lock, flags);
1404 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1405 		spin_unlock_irqrestore(hwep->lock, flags);
1406 		return 0;
1407 	}
1408 
1409 	/* only internal SW should disable ctrl endpts */
1410 
1411 	direction = hwep->dir;
1412 	do {
1413 		retval |= _ep_nuke(hwep);
1414 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1415 
1416 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1417 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1418 
1419 	} while (hwep->dir != direction);
1420 
1421 	hwep->ep.desc = NULL;
1422 
1423 	spin_unlock_irqrestore(hwep->lock, flags);
1424 	return retval;
1425 }
1426 
1427 /**
1428  * ep_alloc_request: allocate a request object to use with this endpoint
1429  *
1430  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1431  */
1432 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1433 {
1434 	struct ci_hw_req *hwreq = NULL;
1435 
1436 	if (ep == NULL)
1437 		return NULL;
1438 
1439 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1440 	if (hwreq != NULL) {
1441 		INIT_LIST_HEAD(&hwreq->queue);
1442 		INIT_LIST_HEAD(&hwreq->tds);
1443 	}
1444 
1445 	return (hwreq == NULL) ? NULL : &hwreq->req;
1446 }
1447 
1448 /**
1449  * ep_free_request: frees a request object
1450  *
1451  * Check usb_ep_free_request() at "usb_gadget.h" for details
1452  */
1453 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1454 {
1455 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1456 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1457 	struct td_node *node, *tmpnode;
1458 	unsigned long flags;
1459 
1460 	if (ep == NULL || req == NULL) {
1461 		return;
1462 	} else if (!list_empty(&hwreq->queue)) {
1463 		dev_err(hwep->ci->dev, "freeing queued request\n");
1464 		return;
1465 	}
1466 
1467 	spin_lock_irqsave(hwep->lock, flags);
1468 
1469 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1470 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1471 		list_del_init(&node->td);
1472 		node->ptr = NULL;
1473 		kfree(node);
1474 	}
1475 
1476 	kfree(hwreq);
1477 
1478 	spin_unlock_irqrestore(hwep->lock, flags);
1479 }
1480 
1481 /**
1482  * ep_queue: queues (submits) an I/O request to an endpoint
1483  *
1484  * Check usb_ep_queue()* at usb_gadget.h" for details
1485  */
1486 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1487 		    gfp_t __maybe_unused gfp_flags)
1488 {
1489 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1490 	int retval = 0;
1491 	unsigned long flags;
1492 
1493 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1494 		return -EINVAL;
1495 
1496 	spin_lock_irqsave(hwep->lock, flags);
1497 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1498 		spin_unlock_irqrestore(hwep->lock, flags);
1499 		return 0;
1500 	}
1501 	retval = _ep_queue(ep, req, gfp_flags);
1502 	spin_unlock_irqrestore(hwep->lock, flags);
1503 	return retval;
1504 }
1505 
1506 /**
1507  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1508  *
1509  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1510  */
1511 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1512 {
1513 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1514 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1515 	unsigned long flags;
1516 	struct td_node *node, *tmpnode;
1517 
1518 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1519 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1520 		list_empty(&hwep->qh.queue))
1521 		return -EINVAL;
1522 
1523 	spin_lock_irqsave(hwep->lock, flags);
1524 	if (hwep->ci->gadget.speed != USB_SPEED_UNKNOWN)
1525 		hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1526 
1527 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1528 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1529 		list_del(&node->td);
1530 		kfree(node);
1531 	}
1532 
1533 	/* pop request */
1534 	list_del_init(&hwreq->queue);
1535 
1536 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1537 
1538 	req->status = -ECONNRESET;
1539 
1540 	if (hwreq->req.complete != NULL) {
1541 		spin_unlock(hwep->lock);
1542 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1543 		spin_lock(hwep->lock);
1544 	}
1545 
1546 	spin_unlock_irqrestore(hwep->lock, flags);
1547 	return 0;
1548 }
1549 
1550 /**
1551  * ep_set_halt: sets the endpoint halt feature
1552  *
1553  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1554  */
1555 static int ep_set_halt(struct usb_ep *ep, int value)
1556 {
1557 	return _ep_set_halt(ep, value, true);
1558 }
1559 
1560 /**
1561  * ep_set_wedge: sets the halt feature and ignores clear requests
1562  *
1563  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1564  */
1565 static int ep_set_wedge(struct usb_ep *ep)
1566 {
1567 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1568 	unsigned long flags;
1569 
1570 	if (ep == NULL || hwep->ep.desc == NULL)
1571 		return -EINVAL;
1572 
1573 	spin_lock_irqsave(hwep->lock, flags);
1574 	hwep->wedge = 1;
1575 	spin_unlock_irqrestore(hwep->lock, flags);
1576 
1577 	return usb_ep_set_halt(ep);
1578 }
1579 
1580 /**
1581  * ep_fifo_flush: flushes contents of a fifo
1582  *
1583  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1584  */
1585 static void ep_fifo_flush(struct usb_ep *ep)
1586 {
1587 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1588 	unsigned long flags;
1589 
1590 	if (ep == NULL) {
1591 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1592 		return;
1593 	}
1594 
1595 	spin_lock_irqsave(hwep->lock, flags);
1596 	if (hwep->ci->gadget.speed == USB_SPEED_UNKNOWN) {
1597 		spin_unlock_irqrestore(hwep->lock, flags);
1598 		return;
1599 	}
1600 
1601 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1602 
1603 	spin_unlock_irqrestore(hwep->lock, flags);
1604 }
1605 
1606 /**
1607  * Endpoint-specific part of the API to the USB controller hardware
1608  * Check "usb_gadget.h" for details
1609  */
1610 static const struct usb_ep_ops usb_ep_ops = {
1611 	.enable	       = ep_enable,
1612 	.disable       = ep_disable,
1613 	.alloc_request = ep_alloc_request,
1614 	.free_request  = ep_free_request,
1615 	.queue	       = ep_queue,
1616 	.dequeue       = ep_dequeue,
1617 	.set_halt      = ep_set_halt,
1618 	.set_wedge     = ep_set_wedge,
1619 	.fifo_flush    = ep_fifo_flush,
1620 };
1621 
1622 /******************************************************************************
1623  * GADGET block
1624  *****************************************************************************/
1625 /**
1626  * ci_hdrc_gadget_connect: caller makes sure gadget driver is binded
1627  */
1628 static void ci_hdrc_gadget_connect(struct usb_gadget *_gadget, int is_active)
1629 {
1630 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1631 
1632 	if (is_active) {
1633 		pm_runtime_get_sync(ci->dev);
1634 		hw_device_reset(ci);
1635 		spin_lock_irq(&ci->lock);
1636 		if (ci->driver) {
1637 			hw_device_state(ci, ci->ep0out->qh.dma);
1638 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1639 			spin_unlock_irq(&ci->lock);
1640 			usb_udc_vbus_handler(_gadget, true);
1641 		} else {
1642 			spin_unlock_irq(&ci->lock);
1643 		}
1644 	} else {
1645 		usb_udc_vbus_handler(_gadget, false);
1646 		if (ci->driver)
1647 			ci->driver->disconnect(&ci->gadget);
1648 		hw_device_state(ci, 0);
1649 		if (ci->platdata->notify_event)
1650 			ci->platdata->notify_event(ci,
1651 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1652 		_gadget_stop_activity(&ci->gadget);
1653 		pm_runtime_put_sync(ci->dev);
1654 		usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1655 	}
1656 }
1657 
1658 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1659 {
1660 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1661 	unsigned long flags;
1662 	int ret = 0;
1663 
1664 	spin_lock_irqsave(&ci->lock, flags);
1665 	ci->vbus_active = is_active;
1666 	spin_unlock_irqrestore(&ci->lock, flags);
1667 
1668 	if (ci->usb_phy)
1669 		usb_phy_set_charger_state(ci->usb_phy, is_active ?
1670 			USB_CHARGER_PRESENT : USB_CHARGER_ABSENT);
1671 
1672 	if (ci->platdata->notify_event)
1673 		ret = ci->platdata->notify_event(ci,
1674 				CI_HDRC_CONTROLLER_VBUS_EVENT);
1675 
1676 	if (ci->driver)
1677 		ci_hdrc_gadget_connect(_gadget, is_active);
1678 
1679 	return ret;
1680 }
1681 
1682 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1683 {
1684 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1685 	unsigned long flags;
1686 	int ret = 0;
1687 
1688 	spin_lock_irqsave(&ci->lock, flags);
1689 	if (ci->gadget.speed == USB_SPEED_UNKNOWN) {
1690 		spin_unlock_irqrestore(&ci->lock, flags);
1691 		return 0;
1692 	}
1693 	if (!ci->remote_wakeup) {
1694 		ret = -EOPNOTSUPP;
1695 		goto out;
1696 	}
1697 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1698 		ret = -EINVAL;
1699 		goto out;
1700 	}
1701 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1702 out:
1703 	spin_unlock_irqrestore(&ci->lock, flags);
1704 	return ret;
1705 }
1706 
1707 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1708 {
1709 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1710 
1711 	if (ci->usb_phy)
1712 		return usb_phy_set_power(ci->usb_phy, ma);
1713 	return -ENOTSUPP;
1714 }
1715 
1716 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1717 {
1718 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1719 	struct ci_hw_ep *hwep = ci->ep0in;
1720 	unsigned long flags;
1721 
1722 	spin_lock_irqsave(hwep->lock, flags);
1723 	_gadget->is_selfpowered = (is_on != 0);
1724 	spin_unlock_irqrestore(hwep->lock, flags);
1725 
1726 	return 0;
1727 }
1728 
1729 /* Change Data+ pullup status
1730  * this func is used by usb_gadget_connect/disconnect
1731  */
1732 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1733 {
1734 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1735 
1736 	/*
1737 	 * Data+ pullup controlled by OTG state machine in OTG fsm mode;
1738 	 * and don't touch Data+ in host mode for dual role config.
1739 	 */
1740 	if (ci_otg_is_fsm_mode(ci) || ci->role == CI_ROLE_HOST)
1741 		return 0;
1742 
1743 	pm_runtime_get_sync(ci->dev);
1744 	if (is_on)
1745 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1746 	else
1747 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1748 	pm_runtime_put_sync(ci->dev);
1749 
1750 	return 0;
1751 }
1752 
1753 static int ci_udc_start(struct usb_gadget *gadget,
1754 			 struct usb_gadget_driver *driver);
1755 static int ci_udc_stop(struct usb_gadget *gadget);
1756 
1757 /* Match ISOC IN from the highest endpoint */
1758 static struct usb_ep *ci_udc_match_ep(struct usb_gadget *gadget,
1759 			      struct usb_endpoint_descriptor *desc,
1760 			      struct usb_ss_ep_comp_descriptor *comp_desc)
1761 {
1762 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1763 	struct usb_ep *ep;
1764 
1765 	if (usb_endpoint_xfer_isoc(desc) && usb_endpoint_dir_in(desc)) {
1766 		list_for_each_entry_reverse(ep, &ci->gadget.ep_list, ep_list) {
1767 			if (ep->caps.dir_in && !ep->claimed)
1768 				return ep;
1769 		}
1770 	}
1771 
1772 	return NULL;
1773 }
1774 
1775 /**
1776  * Device operations part of the API to the USB controller hardware,
1777  * which don't involve endpoints (or i/o)
1778  * Check  "usb_gadget.h" for details
1779  */
1780 static const struct usb_gadget_ops usb_gadget_ops = {
1781 	.vbus_session	= ci_udc_vbus_session,
1782 	.wakeup		= ci_udc_wakeup,
1783 	.set_selfpowered	= ci_udc_selfpowered,
1784 	.pullup		= ci_udc_pullup,
1785 	.vbus_draw	= ci_udc_vbus_draw,
1786 	.udc_start	= ci_udc_start,
1787 	.udc_stop	= ci_udc_stop,
1788 	.match_ep 	= ci_udc_match_ep,
1789 };
1790 
1791 static int init_eps(struct ci_hdrc *ci)
1792 {
1793 	int retval = 0, i, j;
1794 
1795 	for (i = 0; i < ci->hw_ep_max/2; i++)
1796 		for (j = RX; j <= TX; j++) {
1797 			int k = i + j * ci->hw_ep_max/2;
1798 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1799 
1800 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1801 					(j == TX)  ? "in" : "out");
1802 
1803 			hwep->ci          = ci;
1804 			hwep->lock         = &ci->lock;
1805 			hwep->td_pool      = ci->td_pool;
1806 
1807 			hwep->ep.name      = hwep->name;
1808 			hwep->ep.ops       = &usb_ep_ops;
1809 
1810 			if (i == 0) {
1811 				hwep->ep.caps.type_control = true;
1812 			} else {
1813 				hwep->ep.caps.type_iso = true;
1814 				hwep->ep.caps.type_bulk = true;
1815 				hwep->ep.caps.type_int = true;
1816 			}
1817 
1818 			if (j == TX)
1819 				hwep->ep.caps.dir_in = true;
1820 			else
1821 				hwep->ep.caps.dir_out = true;
1822 
1823 			/*
1824 			 * for ep0: maxP defined in desc, for other
1825 			 * eps, maxP is set by epautoconfig() called
1826 			 * by gadget layer
1827 			 */
1828 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1829 
1830 			INIT_LIST_HEAD(&hwep->qh.queue);
1831 			hwep->qh.ptr = dma_pool_zalloc(ci->qh_pool, GFP_KERNEL,
1832 						       &hwep->qh.dma);
1833 			if (hwep->qh.ptr == NULL)
1834 				retval = -ENOMEM;
1835 
1836 			/*
1837 			 * set up shorthands for ep0 out and in endpoints,
1838 			 * don't add to gadget's ep_list
1839 			 */
1840 			if (i == 0) {
1841 				if (j == RX)
1842 					ci->ep0out = hwep;
1843 				else
1844 					ci->ep0in = hwep;
1845 
1846 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1847 				continue;
1848 			}
1849 
1850 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1851 		}
1852 
1853 	return retval;
1854 }
1855 
1856 static void destroy_eps(struct ci_hdrc *ci)
1857 {
1858 	int i;
1859 
1860 	for (i = 0; i < ci->hw_ep_max; i++) {
1861 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1862 
1863 		if (hwep->pending_td)
1864 			free_pending_td(hwep);
1865 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1866 	}
1867 }
1868 
1869 /**
1870  * ci_udc_start: register a gadget driver
1871  * @gadget: our gadget
1872  * @driver: the driver being registered
1873  *
1874  * Interrupts are enabled here.
1875  */
1876 static int ci_udc_start(struct usb_gadget *gadget,
1877 			 struct usb_gadget_driver *driver)
1878 {
1879 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1880 	int retval;
1881 
1882 	if (driver->disconnect == NULL)
1883 		return -EINVAL;
1884 
1885 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1886 	retval = usb_ep_enable(&ci->ep0out->ep);
1887 	if (retval)
1888 		return retval;
1889 
1890 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1891 	retval = usb_ep_enable(&ci->ep0in->ep);
1892 	if (retval)
1893 		return retval;
1894 
1895 	ci->driver = driver;
1896 
1897 	/* Start otg fsm for B-device */
1898 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1899 		ci_hdrc_otg_fsm_start(ci);
1900 		return retval;
1901 	}
1902 
1903 	if (ci->vbus_active)
1904 		ci_hdrc_gadget_connect(gadget, 1);
1905 	else
1906 		usb_udc_vbus_handler(&ci->gadget, false);
1907 
1908 	return retval;
1909 }
1910 
1911 static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
1912 {
1913 	if (!ci_otg_is_fsm_mode(ci))
1914 		return;
1915 
1916 	mutex_lock(&ci->fsm.lock);
1917 	if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
1918 		ci->fsm.a_bidl_adis_tmout = 1;
1919 		ci_hdrc_otg_fsm_start(ci);
1920 	} else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
1921 		ci->fsm.protocol = PROTO_UNDEF;
1922 		ci->fsm.otg->state = OTG_STATE_UNDEFINED;
1923 	}
1924 	mutex_unlock(&ci->fsm.lock);
1925 }
1926 
1927 /**
1928  * ci_udc_stop: unregister a gadget driver
1929  */
1930 static int ci_udc_stop(struct usb_gadget *gadget)
1931 {
1932 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1933 	unsigned long flags;
1934 
1935 	spin_lock_irqsave(&ci->lock, flags);
1936 	ci->driver = NULL;
1937 
1938 	if (ci->vbus_active) {
1939 		hw_device_state(ci, 0);
1940 		spin_unlock_irqrestore(&ci->lock, flags);
1941 		if (ci->platdata->notify_event)
1942 			ci->platdata->notify_event(ci,
1943 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1944 		_gadget_stop_activity(&ci->gadget);
1945 		spin_lock_irqsave(&ci->lock, flags);
1946 		pm_runtime_put(ci->dev);
1947 	}
1948 
1949 	spin_unlock_irqrestore(&ci->lock, flags);
1950 
1951 	ci_udc_stop_for_otg_fsm(ci);
1952 	return 0;
1953 }
1954 
1955 /******************************************************************************
1956  * BUS block
1957  *****************************************************************************/
1958 /**
1959  * udc_irq: ci interrupt handler
1960  *
1961  * This function returns IRQ_HANDLED if the IRQ has been handled
1962  * It locks access to registers
1963  */
1964 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1965 {
1966 	irqreturn_t retval;
1967 	u32 intr;
1968 
1969 	if (ci == NULL)
1970 		return IRQ_HANDLED;
1971 
1972 	spin_lock(&ci->lock);
1973 
1974 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1975 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1976 				USBMODE_CM_DC) {
1977 			spin_unlock(&ci->lock);
1978 			return IRQ_NONE;
1979 		}
1980 	}
1981 	intr = hw_test_and_clear_intr_active(ci);
1982 
1983 	if (intr) {
1984 		/* order defines priority - do NOT change it */
1985 		if (USBi_URI & intr)
1986 			isr_reset_handler(ci);
1987 
1988 		if (USBi_PCI & intr) {
1989 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1990 				USB_SPEED_HIGH : USB_SPEED_FULL;
1991 			if (ci->suspended) {
1992 				if (ci->driver->resume) {
1993 					spin_unlock(&ci->lock);
1994 					ci->driver->resume(&ci->gadget);
1995 					spin_lock(&ci->lock);
1996 				}
1997 				ci->suspended = 0;
1998 				usb_gadget_set_state(&ci->gadget,
1999 						ci->resume_state);
2000 			}
2001 		}
2002 
2003 		if (USBi_UI  & intr)
2004 			isr_tr_complete_handler(ci);
2005 
2006 		if ((USBi_SLI & intr) && !(ci->suspended)) {
2007 			ci->suspended = 1;
2008 			ci->resume_state = ci->gadget.state;
2009 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
2010 			    ci->driver->suspend) {
2011 				spin_unlock(&ci->lock);
2012 				ci->driver->suspend(&ci->gadget);
2013 				spin_lock(&ci->lock);
2014 			}
2015 			usb_gadget_set_state(&ci->gadget,
2016 					USB_STATE_SUSPENDED);
2017 		}
2018 		retval = IRQ_HANDLED;
2019 	} else {
2020 		retval = IRQ_NONE;
2021 	}
2022 	spin_unlock(&ci->lock);
2023 
2024 	return retval;
2025 }
2026 
2027 /**
2028  * udc_start: initialize gadget role
2029  * @ci: chipidea controller
2030  */
2031 static int udc_start(struct ci_hdrc *ci)
2032 {
2033 	struct device *dev = ci->dev;
2034 	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
2035 	int retval = 0;
2036 
2037 	ci->gadget.ops          = &usb_gadget_ops;
2038 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
2039 	ci->gadget.max_speed    = USB_SPEED_HIGH;
2040 	ci->gadget.name         = ci->platdata->name;
2041 	ci->gadget.otg_caps	= otg_caps;
2042 	ci->gadget.sg_supported = 1;
2043 
2044 	if (ci->platdata->flags & CI_HDRC_REQUIRES_ALIGNED_DMA)
2045 		ci->gadget.quirk_avoids_skb_reserve = 1;
2046 
2047 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
2048 						otg_caps->adp_support))
2049 		ci->gadget.is_otg = 1;
2050 
2051 	INIT_LIST_HEAD(&ci->gadget.ep_list);
2052 
2053 	/* alloc resources */
2054 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev->parent,
2055 				       sizeof(struct ci_hw_qh),
2056 				       64, CI_HDRC_PAGE_SIZE);
2057 	if (ci->qh_pool == NULL)
2058 		return -ENOMEM;
2059 
2060 	ci->td_pool = dma_pool_create("ci_hw_td", dev->parent,
2061 				       sizeof(struct ci_hw_td),
2062 				       64, CI_HDRC_PAGE_SIZE);
2063 	if (ci->td_pool == NULL) {
2064 		retval = -ENOMEM;
2065 		goto free_qh_pool;
2066 	}
2067 
2068 	retval = init_eps(ci);
2069 	if (retval)
2070 		goto free_pools;
2071 
2072 	ci->gadget.ep0 = &ci->ep0in->ep;
2073 
2074 	retval = usb_add_gadget_udc(dev, &ci->gadget);
2075 	if (retval)
2076 		goto destroy_eps;
2077 
2078 	return retval;
2079 
2080 destroy_eps:
2081 	destroy_eps(ci);
2082 free_pools:
2083 	dma_pool_destroy(ci->td_pool);
2084 free_qh_pool:
2085 	dma_pool_destroy(ci->qh_pool);
2086 	return retval;
2087 }
2088 
2089 /**
2090  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
2091  *
2092  * No interrupts active, the IRQ has been released
2093  */
2094 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
2095 {
2096 	if (!ci->roles[CI_ROLE_GADGET])
2097 		return;
2098 
2099 	usb_del_gadget_udc(&ci->gadget);
2100 
2101 	destroy_eps(ci);
2102 
2103 	dma_pool_destroy(ci->td_pool);
2104 	dma_pool_destroy(ci->qh_pool);
2105 }
2106 
2107 static int udc_id_switch_for_device(struct ci_hdrc *ci)
2108 {
2109 	if (ci->platdata->pins_device)
2110 		pinctrl_select_state(ci->platdata->pctl,
2111 				     ci->platdata->pins_device);
2112 
2113 	if (ci->is_otg)
2114 		/* Clear and enable BSV irq */
2115 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
2116 					OTGSC_BSVIS | OTGSC_BSVIE);
2117 
2118 	return 0;
2119 }
2120 
2121 static void udc_id_switch_for_host(struct ci_hdrc *ci)
2122 {
2123 	/*
2124 	 * host doesn't care B_SESSION_VALID event
2125 	 * so clear and disbale BSV irq
2126 	 */
2127 	if (ci->is_otg)
2128 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
2129 
2130 	ci->vbus_active = 0;
2131 
2132 	if (ci->platdata->pins_device && ci->platdata->pins_default)
2133 		pinctrl_select_state(ci->platdata->pctl,
2134 				     ci->platdata->pins_default);
2135 }
2136 
2137 /**
2138  * ci_hdrc_gadget_init - initialize device related bits
2139  * ci: the controller
2140  *
2141  * This function initializes the gadget, if the device is "device capable".
2142  */
2143 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
2144 {
2145 	struct ci_role_driver *rdrv;
2146 	int ret;
2147 
2148 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
2149 		return -ENXIO;
2150 
2151 	rdrv = devm_kzalloc(ci->dev, sizeof(*rdrv), GFP_KERNEL);
2152 	if (!rdrv)
2153 		return -ENOMEM;
2154 
2155 	rdrv->start	= udc_id_switch_for_device;
2156 	rdrv->stop	= udc_id_switch_for_host;
2157 	rdrv->irq	= udc_irq;
2158 	rdrv->name	= "gadget";
2159 
2160 	ret = udc_start(ci);
2161 	if (!ret)
2162 		ci->roles[CI_ROLE_GADGET] = rdrv;
2163 
2164 	return ret;
2165 }
2166