xref: /linux/drivers/usb/cdns3/cdns3-ep0.c (revision 811f35ff59b6f99ae272d6f5b96bc9e974f88196)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Cadence USBSS DRD Driver - gadget side.
4  *
5  * Copyright (C) 2018 Cadence Design Systems.
6  * Copyright (C) 2017-2018 NXP
7  *
8  * Authors: Pawel Jez <pjez@cadence.com>,
9  *          Pawel Laszczak <pawell@cadence.com>
10  *          Peter Chen <peter.chen@nxp.com>
11  */
12 
13 #include <linux/usb/composite.h>
14 #include <linux/iopoll.h>
15 
16 #include "cdns3-gadget.h"
17 #include "cdns3-trace.h"
18 
19 static struct usb_endpoint_descriptor cdns3_gadget_ep0_desc = {
20 	.bLength = USB_DT_ENDPOINT_SIZE,
21 	.bDescriptorType = USB_DT_ENDPOINT,
22 	.bmAttributes =	USB_ENDPOINT_XFER_CONTROL,
23 };
24 
25 /**
26  * cdns3_ep0_run_transfer - Do transfer on default endpoint hardware
27  * @priv_dev: extended gadget object
28  * @dma_addr: physical address where data is/will be stored
29  * @length: data length
30  * @erdy: set it to 1 when ERDY packet should be sent -
31  *        exit from flow control state
32  * @zlp: add zero length packet
33  */
34 static void cdns3_ep0_run_transfer(struct cdns3_device *priv_dev,
35 				   dma_addr_t dma_addr,
36 				   unsigned int length, int erdy, int zlp)
37 {
38 	struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
39 	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
40 
41 	priv_ep->trb_pool[0].buffer = cpu_to_le32(TRB_BUFFER(dma_addr));
42 	priv_ep->trb_pool[0].length = cpu_to_le32(TRB_LEN(length));
43 
44 	if (zlp) {
45 		priv_ep->trb_pool[0].control = cpu_to_le32(TRB_CYCLE | TRB_TYPE(TRB_NORMAL));
46 		priv_ep->trb_pool[1].buffer = cpu_to_le32(TRB_BUFFER(dma_addr));
47 		priv_ep->trb_pool[1].length = cpu_to_le32(TRB_LEN(0));
48 		priv_ep->trb_pool[1].control = cpu_to_le32(TRB_CYCLE | TRB_IOC |
49 		    TRB_TYPE(TRB_NORMAL));
50 	} else {
51 		priv_ep->trb_pool[0].control = cpu_to_le32(TRB_CYCLE | TRB_IOC |
52 		    TRB_TYPE(TRB_NORMAL));
53 		priv_ep->trb_pool[1].control = 0;
54 	}
55 
56 	trace_cdns3_prepare_trb(priv_ep, priv_ep->trb_pool);
57 
58 	cdns3_select_ep(priv_dev, priv_dev->ep0_data_dir);
59 
60 	writel(EP_STS_TRBERR, &regs->ep_sts);
61 	writel(EP_TRADDR_TRADDR(priv_ep->trb_pool_dma), &regs->ep_traddr);
62 	trace_cdns3_doorbell_ep0(priv_dev->ep0_data_dir ? "ep0in" : "ep0out",
63 				 readl(&regs->ep_traddr));
64 
65 	/* TRB should be prepared before starting transfer. */
66 	writel(EP_CMD_DRDY, &regs->ep_cmd);
67 
68 	/* Resume controller before arming transfer. */
69 	__cdns3_gadget_wakeup(priv_dev);
70 
71 	if (erdy)
72 		writel(EP_CMD_ERDY, &priv_dev->regs->ep_cmd);
73 }
74 
75 /**
76  * cdns3_ep0_delegate_req - Returns status of handling setup packet
77  * Setup is handled by gadget driver
78  * @priv_dev: extended gadget object
79  * @ctrl_req: pointer to received setup packet
80  *
81  * Returns zero on success or negative value on failure
82  */
83 static int cdns3_ep0_delegate_req(struct cdns3_device *priv_dev,
84 				  struct usb_ctrlrequest *ctrl_req)
85 {
86 	int ret;
87 
88 	spin_unlock(&priv_dev->lock);
89 	priv_dev->setup_pending = 1;
90 	ret = priv_dev->gadget_driver->setup(&priv_dev->gadget, ctrl_req);
91 	priv_dev->setup_pending = 0;
92 	spin_lock(&priv_dev->lock);
93 	return ret;
94 }
95 
96 static void cdns3_prepare_setup_packet(struct cdns3_device *priv_dev)
97 {
98 	priv_dev->ep0_data_dir = 0;
99 	priv_dev->ep0_stage = CDNS3_SETUP_STAGE;
100 	cdns3_ep0_run_transfer(priv_dev, priv_dev->setup_dma,
101 			       sizeof(struct usb_ctrlrequest), 0, 0);
102 }
103 
104 static void cdns3_ep0_complete_setup(struct cdns3_device *priv_dev,
105 				     u8 send_stall, u8 send_erdy)
106 {
107 	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
108 	struct usb_request *request;
109 
110 	request = cdns3_next_request(&priv_ep->pending_req_list);
111 	if (request)
112 		list_del_init(&request->list);
113 
114 	if (send_stall) {
115 		trace_cdns3_halt(priv_ep, send_stall, 0);
116 		/* set_stall on ep0 */
117 		cdns3_select_ep(priv_dev, 0x00);
118 		writel(EP_CMD_SSTALL, &priv_dev->regs->ep_cmd);
119 	} else {
120 		cdns3_prepare_setup_packet(priv_dev);
121 	}
122 
123 	priv_dev->ep0_stage = CDNS3_SETUP_STAGE;
124 	writel((send_erdy ? EP_CMD_ERDY : 0) | EP_CMD_REQ_CMPL,
125 	       &priv_dev->regs->ep_cmd);
126 }
127 
128 /**
129  * cdns3_req_ep0_set_configuration - Handling of SET_CONFIG standard USB request
130  * @priv_dev: extended gadget object
131  * @ctrl_req: pointer to received setup packet
132  *
133  * Returns 0 if success, USB_GADGET_DELAYED_STATUS on deferred status stage,
134  * error code on error
135  */
136 static int cdns3_req_ep0_set_configuration(struct cdns3_device *priv_dev,
137 					   struct usb_ctrlrequest *ctrl_req)
138 {
139 	enum usb_device_state device_state = priv_dev->gadget.state;
140 	u32 config = le16_to_cpu(ctrl_req->wValue);
141 	int result = 0;
142 
143 	switch (device_state) {
144 	case USB_STATE_ADDRESS:
145 		result = cdns3_ep0_delegate_req(priv_dev, ctrl_req);
146 
147 		if (result || !config)
148 			goto reset_config;
149 
150 		break;
151 	case USB_STATE_CONFIGURED:
152 		result = cdns3_ep0_delegate_req(priv_dev, ctrl_req);
153 		if (!config && !result)
154 			goto reset_config;
155 
156 		break;
157 	default:
158 		return -EINVAL;
159 	}
160 
161 	return 0;
162 
163 reset_config:
164 	if (result != USB_GADGET_DELAYED_STATUS)
165 		cdns3_hw_reset_eps_config(priv_dev);
166 
167 	usb_gadget_set_state(&priv_dev->gadget,
168 			     USB_STATE_ADDRESS);
169 
170 	return result;
171 }
172 
173 /**
174  * cdns3_req_ep0_set_address - Handling of SET_ADDRESS standard USB request
175  * @priv_dev: extended gadget object
176  * @ctrl_req: pointer to received setup packet
177  *
178  * Returns 0 if success, error code on error
179  */
180 static int cdns3_req_ep0_set_address(struct cdns3_device *priv_dev,
181 				     struct usb_ctrlrequest *ctrl_req)
182 {
183 	enum usb_device_state device_state = priv_dev->gadget.state;
184 	u32 reg;
185 	u32 addr;
186 
187 	addr = le16_to_cpu(ctrl_req->wValue);
188 
189 	if (addr > USB_DEVICE_MAX_ADDRESS) {
190 		dev_err(priv_dev->dev,
191 			"Device address (%d) cannot be greater than %d\n",
192 			addr, USB_DEVICE_MAX_ADDRESS);
193 		return -EINVAL;
194 	}
195 
196 	if (device_state == USB_STATE_CONFIGURED) {
197 		dev_err(priv_dev->dev,
198 			"can't set_address from configured state\n");
199 		return -EINVAL;
200 	}
201 
202 	reg = readl(&priv_dev->regs->usb_cmd);
203 
204 	writel(reg | USB_CMD_FADDR(addr) | USB_CMD_SET_ADDR,
205 	       &priv_dev->regs->usb_cmd);
206 
207 	usb_gadget_set_state(&priv_dev->gadget,
208 			     (addr ? USB_STATE_ADDRESS : USB_STATE_DEFAULT));
209 
210 	return 0;
211 }
212 
213 /**
214  * cdns3_req_ep0_get_status - Handling of GET_STATUS standard USB request
215  * @priv_dev: extended gadget object
216  * @ctrl: pointer to received setup packet
217  *
218  * Returns 0 if success, error code on error
219  */
220 static int cdns3_req_ep0_get_status(struct cdns3_device *priv_dev,
221 				    struct usb_ctrlrequest *ctrl)
222 {
223 	struct cdns3_endpoint *priv_ep;
224 	__le16 *response_pkt;
225 	u16 usb_status = 0;
226 	u32 recip;
227 	u8 index;
228 
229 	recip = ctrl->bRequestType & USB_RECIP_MASK;
230 
231 	switch (recip) {
232 	case USB_RECIP_DEVICE:
233 		/* self powered */
234 		if (priv_dev->is_selfpowered)
235 			usb_status = BIT(USB_DEVICE_SELF_POWERED);
236 
237 		if (priv_dev->wake_up_flag)
238 			usb_status |= BIT(USB_DEVICE_REMOTE_WAKEUP);
239 
240 		if (priv_dev->gadget.speed != USB_SPEED_SUPER)
241 			break;
242 
243 		if (priv_dev->u1_allowed)
244 			usb_status |= BIT(USB_DEV_STAT_U1_ENABLED);
245 
246 		if (priv_dev->u2_allowed)
247 			usb_status |= BIT(USB_DEV_STAT_U2_ENABLED);
248 
249 		break;
250 	case USB_RECIP_INTERFACE:
251 		return cdns3_ep0_delegate_req(priv_dev, ctrl);
252 	case USB_RECIP_ENDPOINT:
253 		index = cdns3_ep_addr_to_index(le16_to_cpu(ctrl->wIndex));
254 		priv_ep = priv_dev->eps[index];
255 
256 		/* check if endpoint is stalled or stall is pending */
257 		cdns3_select_ep(priv_dev, le16_to_cpu(ctrl->wIndex));
258 		if (EP_STS_STALL(readl(&priv_dev->regs->ep_sts)) ||
259 		    (priv_ep->flags & EP_STALL_PENDING))
260 			usb_status =  BIT(USB_ENDPOINT_HALT);
261 		break;
262 	default:
263 		return -EINVAL;
264 	}
265 
266 	response_pkt = (__le16 *)priv_dev->setup_buf;
267 	*response_pkt = cpu_to_le16(usb_status);
268 
269 	cdns3_ep0_run_transfer(priv_dev, priv_dev->setup_dma,
270 			       sizeof(*response_pkt), 1, 0);
271 	return 0;
272 }
273 
274 static int cdns3_ep0_feature_handle_device(struct cdns3_device *priv_dev,
275 					   struct usb_ctrlrequest *ctrl,
276 					   int set)
277 {
278 	enum usb_device_state state;
279 	enum usb_device_speed speed;
280 	int ret = 0;
281 	u32 wValue;
282 	u16 tmode;
283 
284 	wValue = le16_to_cpu(ctrl->wValue);
285 	state = priv_dev->gadget.state;
286 	speed = priv_dev->gadget.speed;
287 
288 	switch (wValue) {
289 	case USB_DEVICE_REMOTE_WAKEUP:
290 		priv_dev->wake_up_flag = !!set;
291 		break;
292 	case USB_DEVICE_U1_ENABLE:
293 		if (state != USB_STATE_CONFIGURED || speed != USB_SPEED_SUPER)
294 			return -EINVAL;
295 
296 		priv_dev->u1_allowed = !!set;
297 		break;
298 	case USB_DEVICE_U2_ENABLE:
299 		if (state != USB_STATE_CONFIGURED || speed != USB_SPEED_SUPER)
300 			return -EINVAL;
301 
302 		priv_dev->u2_allowed = !!set;
303 		break;
304 	case USB_DEVICE_LTM_ENABLE:
305 		ret = -EINVAL;
306 		break;
307 	case USB_DEVICE_TEST_MODE:
308 		if (state != USB_STATE_CONFIGURED || speed > USB_SPEED_HIGH)
309 			return -EINVAL;
310 
311 		tmode = le16_to_cpu(ctrl->wIndex);
312 
313 		if (!set || (tmode & 0xff) != 0)
314 			return -EINVAL;
315 
316 		tmode >>= 8;
317 		switch (tmode) {
318 		case USB_TEST_J:
319 		case USB_TEST_K:
320 		case USB_TEST_SE0_NAK:
321 		case USB_TEST_PACKET:
322 			cdns3_set_register_bit(&priv_dev->regs->usb_cmd,
323 					       USB_CMD_STMODE |
324 					       USB_STS_TMODE_SEL(tmode - 1));
325 			break;
326 		default:
327 			ret = -EINVAL;
328 		}
329 		break;
330 	default:
331 		ret = -EINVAL;
332 	}
333 
334 	return ret;
335 }
336 
337 static int cdns3_ep0_feature_handle_intf(struct cdns3_device *priv_dev,
338 					 struct usb_ctrlrequest *ctrl,
339 					 int set)
340 {
341 	u32 wValue;
342 	int ret = 0;
343 
344 	wValue = le16_to_cpu(ctrl->wValue);
345 
346 	switch (wValue) {
347 	case USB_INTRF_FUNC_SUSPEND:
348 		break;
349 	default:
350 		ret = -EINVAL;
351 	}
352 
353 	return ret;
354 }
355 
356 static int cdns3_ep0_feature_handle_endpoint(struct cdns3_device *priv_dev,
357 					     struct usb_ctrlrequest *ctrl,
358 					     int set)
359 {
360 	struct cdns3_endpoint *priv_ep;
361 	int ret = 0;
362 	u8 index;
363 
364 	if (le16_to_cpu(ctrl->wValue) != USB_ENDPOINT_HALT)
365 		return -EINVAL;
366 
367 	if (!(le16_to_cpu(ctrl->wIndex) & ~USB_DIR_IN))
368 		return 0;
369 
370 	index = cdns3_ep_addr_to_index(le16_to_cpu(ctrl->wIndex));
371 	priv_ep = priv_dev->eps[index];
372 
373 	cdns3_select_ep(priv_dev, le16_to_cpu(ctrl->wIndex));
374 
375 	if (set)
376 		__cdns3_gadget_ep_set_halt(priv_ep);
377 	else if (!(priv_ep->flags & EP_WEDGE))
378 		ret = __cdns3_gadget_ep_clear_halt(priv_ep);
379 
380 	cdns3_select_ep(priv_dev, 0x00);
381 
382 	return ret;
383 }
384 
385 /**
386  * cdns3_req_ep0_handle_feature -
387  * Handling of GET/SET_FEATURE standard USB request
388  *
389  * @priv_dev: extended gadget object
390  * @ctrl: pointer to received setup packet
391  * @set: must be set to 1 for SET_FEATURE request
392  *
393  * Returns 0 if success, error code on error
394  */
395 static int cdns3_req_ep0_handle_feature(struct cdns3_device *priv_dev,
396 					struct usb_ctrlrequest *ctrl,
397 					int set)
398 {
399 	int ret = 0;
400 	u32 recip;
401 
402 	recip = ctrl->bRequestType & USB_RECIP_MASK;
403 
404 	switch (recip) {
405 	case USB_RECIP_DEVICE:
406 		ret = cdns3_ep0_feature_handle_device(priv_dev, ctrl, set);
407 		break;
408 	case USB_RECIP_INTERFACE:
409 		ret = cdns3_ep0_feature_handle_intf(priv_dev, ctrl, set);
410 		break;
411 	case USB_RECIP_ENDPOINT:
412 		ret = cdns3_ep0_feature_handle_endpoint(priv_dev, ctrl, set);
413 		break;
414 	default:
415 		return -EINVAL;
416 	}
417 
418 	return ret;
419 }
420 
421 /**
422  * cdns3_req_ep0_set_sel - Handling of SET_SEL standard USB request
423  * @priv_dev: extended gadget object
424  * @ctrl_req: pointer to received setup packet
425  *
426  * Returns 0 if success, error code on error
427  */
428 static int cdns3_req_ep0_set_sel(struct cdns3_device *priv_dev,
429 				 struct usb_ctrlrequest *ctrl_req)
430 {
431 	if (priv_dev->gadget.state < USB_STATE_ADDRESS)
432 		return -EINVAL;
433 
434 	if (le16_to_cpu(ctrl_req->wLength) != 6) {
435 		dev_err(priv_dev->dev, "Set SEL should be 6 bytes, got %d\n",
436 			ctrl_req->wLength);
437 		return -EINVAL;
438 	}
439 
440 	cdns3_ep0_run_transfer(priv_dev, priv_dev->setup_dma, 6, 1, 0);
441 	return 0;
442 }
443 
444 /**
445  * cdns3_req_ep0_set_isoch_delay -
446  * Handling of GET_ISOCH_DELAY standard USB request
447  * @priv_dev: extended gadget object
448  * @ctrl_req: pointer to received setup packet
449  *
450  * Returns 0 if success, error code on error
451  */
452 static int cdns3_req_ep0_set_isoch_delay(struct cdns3_device *priv_dev,
453 					 struct usb_ctrlrequest *ctrl_req)
454 {
455 	if (ctrl_req->wIndex || ctrl_req->wLength)
456 		return -EINVAL;
457 
458 	priv_dev->isoch_delay = le16_to_cpu(ctrl_req->wValue);
459 
460 	return 0;
461 }
462 
463 /**
464  * cdns3_ep0_standard_request - Handling standard USB requests
465  * @priv_dev: extended gadget object
466  * @ctrl_req: pointer to received setup packet
467  *
468  * Returns 0 if success, error code on error
469  */
470 static int cdns3_ep0_standard_request(struct cdns3_device *priv_dev,
471 				      struct usb_ctrlrequest *ctrl_req)
472 {
473 	int ret;
474 
475 	switch (ctrl_req->bRequest) {
476 	case USB_REQ_SET_ADDRESS:
477 		ret = cdns3_req_ep0_set_address(priv_dev, ctrl_req);
478 		break;
479 	case USB_REQ_SET_CONFIGURATION:
480 		ret = cdns3_req_ep0_set_configuration(priv_dev, ctrl_req);
481 		break;
482 	case USB_REQ_GET_STATUS:
483 		ret = cdns3_req_ep0_get_status(priv_dev, ctrl_req);
484 		break;
485 	case USB_REQ_CLEAR_FEATURE:
486 		ret = cdns3_req_ep0_handle_feature(priv_dev, ctrl_req, 0);
487 		break;
488 	case USB_REQ_SET_FEATURE:
489 		ret = cdns3_req_ep0_handle_feature(priv_dev, ctrl_req, 1);
490 		break;
491 	case USB_REQ_SET_SEL:
492 		ret = cdns3_req_ep0_set_sel(priv_dev, ctrl_req);
493 		break;
494 	case USB_REQ_SET_ISOCH_DELAY:
495 		ret = cdns3_req_ep0_set_isoch_delay(priv_dev, ctrl_req);
496 		break;
497 	default:
498 		ret = cdns3_ep0_delegate_req(priv_dev, ctrl_req);
499 		break;
500 	}
501 
502 	return ret;
503 }
504 
505 static void __pending_setup_status_handler(struct cdns3_device *priv_dev)
506 {
507 	struct usb_request *request = priv_dev->pending_status_request;
508 
509 	if (priv_dev->status_completion_no_call && request &&
510 	    request->complete) {
511 		request->complete(&priv_dev->eps[0]->endpoint, request);
512 		priv_dev->status_completion_no_call = 0;
513 	}
514 }
515 
516 void cdns3_pending_setup_status_handler(struct work_struct *work)
517 {
518 	struct cdns3_device *priv_dev = container_of(work, struct cdns3_device,
519 			pending_status_wq);
520 	unsigned long flags;
521 
522 	spin_lock_irqsave(&priv_dev->lock, flags);
523 	__pending_setup_status_handler(priv_dev);
524 	spin_unlock_irqrestore(&priv_dev->lock, flags);
525 }
526 
527 /**
528  * cdns3_ep0_setup_phase - Handling setup USB requests
529  * @priv_dev: extended gadget object
530  */
531 static void cdns3_ep0_setup_phase(struct cdns3_device *priv_dev)
532 {
533 	struct usb_ctrlrequest *ctrl = priv_dev->setup_buf;
534 	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
535 	int result;
536 
537 	priv_dev->ep0_data_dir = ctrl->bRequestType & USB_DIR_IN;
538 
539 	trace_cdns3_ctrl_req(ctrl);
540 
541 	if (!list_empty(&priv_ep->pending_req_list)) {
542 		struct usb_request *request;
543 
544 		request = cdns3_next_request(&priv_ep->pending_req_list);
545 		priv_ep->dir = priv_dev->ep0_data_dir;
546 		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request),
547 				      -ECONNRESET);
548 	}
549 
550 	if (le16_to_cpu(ctrl->wLength))
551 		priv_dev->ep0_stage = CDNS3_DATA_STAGE;
552 	else
553 		priv_dev->ep0_stage = CDNS3_STATUS_STAGE;
554 
555 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
556 		result = cdns3_ep0_standard_request(priv_dev, ctrl);
557 	else
558 		result = cdns3_ep0_delegate_req(priv_dev, ctrl);
559 
560 	if (result == USB_GADGET_DELAYED_STATUS)
561 		return;
562 
563 	if (result < 0)
564 		cdns3_ep0_complete_setup(priv_dev, 1, 1);
565 	else if (priv_dev->ep0_stage == CDNS3_STATUS_STAGE)
566 		cdns3_ep0_complete_setup(priv_dev, 0, 1);
567 }
568 
569 static void cdns3_transfer_completed(struct cdns3_device *priv_dev)
570 {
571 	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
572 
573 	if (!list_empty(&priv_ep->pending_req_list)) {
574 		struct usb_request *request;
575 
576 		trace_cdns3_complete_trb(priv_ep, priv_ep->trb_pool);
577 		request = cdns3_next_request(&priv_ep->pending_req_list);
578 
579 		request->actual =
580 			TRB_LEN(le32_to_cpu(priv_ep->trb_pool->length));
581 
582 		priv_ep->dir = priv_dev->ep0_data_dir;
583 		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request), 0);
584 	}
585 
586 	cdns3_ep0_complete_setup(priv_dev, 0, 0);
587 }
588 
589 /**
590  * cdns3_check_new_setup - Check if controller receive new SETUP packet.
591  * @priv_dev: extended gadget object
592  *
593  * The SETUP packet can be kept in on-chip memory or in system memory.
594  */
595 static bool cdns3_check_new_setup(struct cdns3_device *priv_dev)
596 {
597 	u32 ep_sts_reg;
598 
599 	cdns3_select_ep(priv_dev, USB_DIR_OUT);
600 	ep_sts_reg = readl(&priv_dev->regs->ep_sts);
601 
602 	return !!(ep_sts_reg & (EP_STS_SETUP | EP_STS_STPWAIT));
603 }
604 
605 /**
606  * cdns3_check_ep0_interrupt_proceed - Processes interrupt related to endpoint 0
607  * @priv_dev: extended gadget object
608  * @dir: USB_DIR_IN for IN direction, USB_DIR_OUT for OUT direction
609  */
610 void cdns3_check_ep0_interrupt_proceed(struct cdns3_device *priv_dev, int dir)
611 {
612 	u32 ep_sts_reg;
613 
614 	cdns3_select_ep(priv_dev, dir);
615 
616 	ep_sts_reg = readl(&priv_dev->regs->ep_sts);
617 	writel(ep_sts_reg, &priv_dev->regs->ep_sts);
618 
619 	trace_cdns3_ep0_irq(priv_dev, ep_sts_reg);
620 
621 	__pending_setup_status_handler(priv_dev);
622 
623 	if (ep_sts_reg & EP_STS_SETUP)
624 		priv_dev->wait_for_setup = 1;
625 
626 	if (priv_dev->wait_for_setup && ep_sts_reg & EP_STS_IOC) {
627 		priv_dev->wait_for_setup = 0;
628 		cdns3_ep0_setup_phase(priv_dev);
629 	} else if ((ep_sts_reg & EP_STS_IOC) || (ep_sts_reg & EP_STS_ISP)) {
630 		priv_dev->ep0_data_dir = dir;
631 		cdns3_transfer_completed(priv_dev);
632 	}
633 
634 	if (ep_sts_reg & EP_STS_DESCMIS) {
635 		if (dir == 0 && !priv_dev->setup_pending)
636 			cdns3_prepare_setup_packet(priv_dev);
637 	}
638 }
639 
640 /**
641  * cdns3_gadget_ep0_enable
642  * @ep: pointer to endpoint zero object
643  * @desc: pointer to usb endpoint descriptor
644  *
645  * Function shouldn't be called by gadget driver,
646  * endpoint 0 is allways active
647  */
648 static int cdns3_gadget_ep0_enable(struct usb_ep *ep,
649 				   const struct usb_endpoint_descriptor *desc)
650 {
651 	return -EINVAL;
652 }
653 
654 /**
655  * cdns3_gadget_ep0_disable
656  * @ep: pointer to endpoint zero object
657  *
658  * Function shouldn't be called by gadget driver,
659  * endpoint 0 is allways active
660  */
661 static int cdns3_gadget_ep0_disable(struct usb_ep *ep)
662 {
663 	return -EINVAL;
664 }
665 
666 /**
667  * cdns3_gadget_ep0_set_halt
668  * @ep: pointer to endpoint zero object
669  * @value: 1 for set stall, 0 for clear stall
670  *
671  * Returns 0
672  */
673 static int cdns3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
674 {
675 	/* TODO */
676 	return 0;
677 }
678 
679 /**
680  * cdns3_gadget_ep0_queue - Transfer data on endpoint zero
681  * @ep: pointer to endpoint zero object
682  * @request: pointer to request object
683  * @gfp_flags: gfp flags
684  *
685  * Returns 0 on success, error code elsewhere
686  */
687 static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
688 				  struct usb_request *request,
689 				  gfp_t gfp_flags)
690 {
691 	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
692 	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
693 	unsigned long flags;
694 	int ret = 0;
695 	u8 zlp = 0;
696 	int i;
697 
698 	spin_lock_irqsave(&priv_dev->lock, flags);
699 	trace_cdns3_ep0_queue(priv_dev, request);
700 
701 	/* cancel the request if controller receive new SETUP packet. */
702 	if (cdns3_check_new_setup(priv_dev)) {
703 		spin_unlock_irqrestore(&priv_dev->lock, flags);
704 		return -ECONNRESET;
705 	}
706 
707 	/* send STATUS stage. Should be called only for SET_CONFIGURATION */
708 	if (priv_dev->ep0_stage == CDNS3_STATUS_STAGE) {
709 		u32 val;
710 
711 		cdns3_select_ep(priv_dev, 0x00);
712 
713 		/*
714 		 * Configure all non-control EPs which are not enabled by class driver
715 		 */
716 		for (i = 0; i < CDNS3_ENDPOINTS_MAX_COUNT; i++) {
717 			priv_ep = priv_dev->eps[i];
718 			if (priv_ep && priv_ep->flags & EP_CLAIMED &&
719 			    !(priv_ep->flags & EP_ENABLED))
720 				cdns3_ep_config(priv_ep, 0);
721 		}
722 
723 		cdns3_set_hw_configuration(priv_dev);
724 		cdns3_ep0_complete_setup(priv_dev, 0, 1);
725 		/* wait until configuration set */
726 		ret = readl_poll_timeout_atomic(&priv_dev->regs->usb_sts, val,
727 					  val & USB_STS_CFGSTS_MASK, 1, 100);
728 		if (ret == -ETIMEDOUT)
729 			dev_warn(priv_dev->dev, "timeout for waiting configuration set\n");
730 
731 		request->actual = 0;
732 		priv_dev->status_completion_no_call = true;
733 		priv_dev->pending_status_request = request;
734 		usb_gadget_set_state(&priv_dev->gadget, USB_STATE_CONFIGURED);
735 		spin_unlock_irqrestore(&priv_dev->lock, flags);
736 
737 		/*
738 		 * Since there is no completion interrupt for status stage,
739 		 * it needs to call ->completion in software after
740 		 * ep0_queue is back.
741 		 */
742 		queue_work(system_freezable_wq, &priv_dev->pending_status_wq);
743 		return ret;
744 	}
745 
746 	if (!list_empty(&priv_ep->pending_req_list)) {
747 		dev_err(priv_dev->dev,
748 			"can't handle multiple requests for ep0\n");
749 		spin_unlock_irqrestore(&priv_dev->lock, flags);
750 		return -EBUSY;
751 	}
752 
753 	ret = usb_gadget_map_request_by_dev(priv_dev->sysdev, request,
754 					    priv_dev->ep0_data_dir);
755 	if (ret) {
756 		spin_unlock_irqrestore(&priv_dev->lock, flags);
757 		dev_err(priv_dev->dev, "failed to map request\n");
758 		return -EINVAL;
759 	}
760 
761 	request->status = -EINPROGRESS;
762 	list_add_tail(&request->list, &priv_ep->pending_req_list);
763 
764 	if (request->zero && request->length &&
765 	    (request->length % ep->maxpacket == 0))
766 		zlp = 1;
767 
768 	cdns3_ep0_run_transfer(priv_dev, request->dma, request->length, 1, zlp);
769 
770 	spin_unlock_irqrestore(&priv_dev->lock, flags);
771 
772 	return ret;
773 }
774 
775 /**
776  * cdns3_gadget_ep_set_wedge - Set wedge on selected endpoint
777  * @ep: endpoint object
778  *
779  * Returns 0
780  */
781 int cdns3_gadget_ep_set_wedge(struct usb_ep *ep)
782 {
783 	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
784 	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
785 
786 	dev_dbg(priv_dev->dev, "Wedge for %s\n", ep->name);
787 	cdns3_gadget_ep_set_halt(ep, 1);
788 	priv_ep->flags |= EP_WEDGE;
789 
790 	return 0;
791 }
792 
793 static const struct usb_ep_ops cdns3_gadget_ep0_ops = {
794 	.enable = cdns3_gadget_ep0_enable,
795 	.disable = cdns3_gadget_ep0_disable,
796 	.alloc_request = cdns3_gadget_ep_alloc_request,
797 	.free_request = cdns3_gadget_ep_free_request,
798 	.queue = cdns3_gadget_ep0_queue,
799 	.dequeue = cdns3_gadget_ep_dequeue,
800 	.set_halt = cdns3_gadget_ep0_set_halt,
801 	.set_wedge = cdns3_gadget_ep_set_wedge,
802 };
803 
804 /**
805  * cdns3_ep0_config - Configures default endpoint
806  * @priv_dev: extended gadget object
807  *
808  * Functions sets parameters: maximal packet size and enables interrupts
809  */
810 void cdns3_ep0_config(struct cdns3_device *priv_dev)
811 {
812 	struct cdns3_usb_regs __iomem *regs;
813 	struct cdns3_endpoint *priv_ep;
814 	u32 max_packet_size = 64;
815 	u32 ep_cfg;
816 
817 	regs = priv_dev->regs;
818 
819 	if (priv_dev->gadget.speed == USB_SPEED_SUPER)
820 		max_packet_size = 512;
821 
822 	priv_ep = priv_dev->eps[0];
823 
824 	if (!list_empty(&priv_ep->pending_req_list)) {
825 		struct usb_request *request;
826 
827 		request = cdns3_next_request(&priv_ep->pending_req_list);
828 		list_del_init(&request->list);
829 	}
830 
831 	priv_dev->u1_allowed = 0;
832 	priv_dev->u2_allowed = 0;
833 
834 	priv_dev->gadget.ep0->maxpacket = max_packet_size;
835 	cdns3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(max_packet_size);
836 
837 	/* init ep out */
838 	cdns3_select_ep(priv_dev, USB_DIR_OUT);
839 
840 	if (priv_dev->dev_ver >= DEV_VER_V3) {
841 		cdns3_set_register_bit(&priv_dev->regs->dtrans,
842 				       BIT(0) | BIT(16));
843 		cdns3_set_register_bit(&priv_dev->regs->tdl_from_trb,
844 				       BIT(0) | BIT(16));
845 	}
846 
847 	ep_cfg = EP_CFG_ENABLE | EP_CFG_MAXPKTSIZE(max_packet_size);
848 
849 	if (!(priv_ep->flags & EP_CONFIGURED))
850 		writel(ep_cfg, &regs->ep_cfg);
851 
852 	writel(EP_STS_EN_SETUPEN | EP_STS_EN_DESCMISEN | EP_STS_EN_TRBERREN,
853 	       &regs->ep_sts_en);
854 
855 	/* init ep in */
856 	cdns3_select_ep(priv_dev, USB_DIR_IN);
857 
858 	if (!(priv_ep->flags & EP_CONFIGURED))
859 		writel(ep_cfg, &regs->ep_cfg);
860 
861 	priv_ep->flags |= EP_CONFIGURED;
862 
863 	writel(EP_STS_EN_SETUPEN | EP_STS_EN_TRBERREN, &regs->ep_sts_en);
864 
865 	cdns3_set_register_bit(&regs->usb_conf, USB_CONF_U1DS | USB_CONF_U2DS);
866 }
867 
868 /**
869  * cdns3_init_ep0 - Initializes software endpoint 0 of gadget
870  * @priv_dev: extended gadget object
871  * @priv_ep: extended endpoint object
872  *
873  * Returns 0 on success else error code.
874  */
875 int cdns3_init_ep0(struct cdns3_device *priv_dev,
876 		   struct cdns3_endpoint *priv_ep)
877 {
878 	sprintf(priv_ep->name, "ep0");
879 
880 	/* fill linux fields */
881 	priv_ep->endpoint.ops = &cdns3_gadget_ep0_ops;
882 	priv_ep->endpoint.maxburst = 1;
883 	usb_ep_set_maxpacket_limit(&priv_ep->endpoint,
884 				   CDNS3_EP0_MAX_PACKET_LIMIT);
885 	priv_ep->endpoint.address = 0;
886 	priv_ep->endpoint.caps.type_control = 1;
887 	priv_ep->endpoint.caps.dir_in = 1;
888 	priv_ep->endpoint.caps.dir_out = 1;
889 	priv_ep->endpoint.name = priv_ep->name;
890 	priv_ep->endpoint.desc = &cdns3_gadget_ep0_desc;
891 	priv_dev->gadget.ep0 = &priv_ep->endpoint;
892 	priv_ep->type = USB_ENDPOINT_XFER_CONTROL;
893 
894 	return cdns3_allocate_trb_pool(priv_ep);
895 }
896