xref: /linux/drivers/usb/chipidea/udc.c (revision 9429ec96c2718c0d1e3317cf60a87a0405223814)
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/dma-mapping.h>
17 #include <linux/err.h>
18 #include <linux/init.h>
19 #include <linux/platform_device.h>
20 #include <linux/module.h>
21 #include <linux/interrupt.h>
22 #include <linux/io.h>
23 #include <linux/irq.h>
24 #include <linux/kernel.h>
25 #include <linux/slab.h>
26 #include <linux/pm_runtime.h>
27 #include <linux/usb/ch9.h>
28 #include <linux/usb/gadget.h>
29 #include <linux/usb/otg.h>
30 #include <linux/usb/chipidea.h>
31 
32 #include "ci.h"
33 #include "udc.h"
34 #include "bits.h"
35 #include "debug.h"
36 
37 /* control endpoint description */
38 static const struct usb_endpoint_descriptor
39 ctrl_endpt_out_desc = {
40 	.bLength         = USB_DT_ENDPOINT_SIZE,
41 	.bDescriptorType = USB_DT_ENDPOINT,
42 
43 	.bEndpointAddress = USB_DIR_OUT,
44 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
45 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
46 };
47 
48 static const struct usb_endpoint_descriptor
49 ctrl_endpt_in_desc = {
50 	.bLength         = USB_DT_ENDPOINT_SIZE,
51 	.bDescriptorType = USB_DT_ENDPOINT,
52 
53 	.bEndpointAddress = USB_DIR_IN,
54 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
55 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
56 };
57 
58 /**
59  * hw_ep_bit: calculates the bit number
60  * @num: endpoint number
61  * @dir: endpoint direction
62  *
63  * This function returns bit number
64  */
65 static inline int hw_ep_bit(int num, int dir)
66 {
67 	return num + (dir ? 16 : 0);
68 }
69 
70 static inline int ep_to_bit(struct ci13xxx *ci, int n)
71 {
72 	int fill = 16 - ci->hw_ep_max / 2;
73 
74 	if (n >= ci->hw_ep_max / 2)
75 		n += fill;
76 
77 	return n;
78 }
79 
80 /**
81  * hw_device_state: enables/disables interrupts (execute without interruption)
82  * @dma: 0 => disable, !0 => enable and set dma engine
83  *
84  * This function returns an error code
85  */
86 static int hw_device_state(struct ci13xxx *ci, u32 dma)
87 {
88 	if (dma) {
89 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
90 		/* interrupt, error, port change, reset, sleep/suspend */
91 		hw_write(ci, OP_USBINTR, ~0,
92 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
93 	} else {
94 		hw_write(ci, OP_USBINTR, ~0, 0);
95 	}
96 	return 0;
97 }
98 
99 /**
100  * hw_ep_flush: flush endpoint fifo (execute without interruption)
101  * @num: endpoint number
102  * @dir: endpoint direction
103  *
104  * This function returns an error code
105  */
106 static int hw_ep_flush(struct ci13xxx *ci, int num, int dir)
107 {
108 	int n = hw_ep_bit(num, dir);
109 
110 	do {
111 		/* flush any pending transfer */
112 		hw_write(ci, OP_ENDPTFLUSH, BIT(n), BIT(n));
113 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
114 			cpu_relax();
115 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
116 
117 	return 0;
118 }
119 
120 /**
121  * hw_ep_disable: disables endpoint (execute without interruption)
122  * @num: endpoint number
123  * @dir: endpoint direction
124  *
125  * This function returns an error code
126  */
127 static int hw_ep_disable(struct ci13xxx *ci, int num, int dir)
128 {
129 	hw_ep_flush(ci, num, dir);
130 	hw_write(ci, OP_ENDPTCTRL + num,
131 		 dir ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
132 	return 0;
133 }
134 
135 /**
136  * hw_ep_enable: enables endpoint (execute without interruption)
137  * @num:  endpoint number
138  * @dir:  endpoint direction
139  * @type: endpoint type
140  *
141  * This function returns an error code
142  */
143 static int hw_ep_enable(struct ci13xxx *ci, int num, int dir, int type)
144 {
145 	u32 mask, data;
146 
147 	if (dir) {
148 		mask  = ENDPTCTRL_TXT;  /* type    */
149 		data  = type << ffs_nr(mask);
150 
151 		mask |= ENDPTCTRL_TXS;  /* unstall */
152 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
153 		data |= ENDPTCTRL_TXR;
154 		mask |= ENDPTCTRL_TXE;  /* enable  */
155 		data |= ENDPTCTRL_TXE;
156 	} else {
157 		mask  = ENDPTCTRL_RXT;  /* type    */
158 		data  = type << ffs_nr(mask);
159 
160 		mask |= ENDPTCTRL_RXS;  /* unstall */
161 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
162 		data |= ENDPTCTRL_RXR;
163 		mask |= ENDPTCTRL_RXE;  /* enable  */
164 		data |= ENDPTCTRL_RXE;
165 	}
166 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
167 	return 0;
168 }
169 
170 /**
171  * hw_ep_get_halt: return endpoint halt status
172  * @num: endpoint number
173  * @dir: endpoint direction
174  *
175  * This function returns 1 if endpoint halted
176  */
177 static int hw_ep_get_halt(struct ci13xxx *ci, int num, int dir)
178 {
179 	u32 mask = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
180 
181 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
182 }
183 
184 /**
185  * hw_test_and_clear_setup_status: test & clear setup status (execute without
186  *                                 interruption)
187  * @n: endpoint number
188  *
189  * This function returns setup status
190  */
191 static int hw_test_and_clear_setup_status(struct ci13xxx *ci, int n)
192 {
193 	n = ep_to_bit(ci, n);
194 	return hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(n));
195 }
196 
197 /**
198  * hw_ep_prime: primes endpoint (execute without interruption)
199  * @num:     endpoint number
200  * @dir:     endpoint direction
201  * @is_ctrl: true if control endpoint
202  *
203  * This function returns an error code
204  */
205 static int hw_ep_prime(struct ci13xxx *ci, int num, int dir, int is_ctrl)
206 {
207 	int n = hw_ep_bit(num, dir);
208 
209 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
210 		return -EAGAIN;
211 
212 	hw_write(ci, OP_ENDPTPRIME, BIT(n), BIT(n));
213 
214 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
215 		cpu_relax();
216 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
217 		return -EAGAIN;
218 
219 	/* status shoult be tested according with manual but it doesn't work */
220 	return 0;
221 }
222 
223 /**
224  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
225  *                 without interruption)
226  * @num:   endpoint number
227  * @dir:   endpoint direction
228  * @value: true => stall, false => unstall
229  *
230  * This function returns an error code
231  */
232 static int hw_ep_set_halt(struct ci13xxx *ci, int num, int dir, int value)
233 {
234 	if (value != 0 && value != 1)
235 		return -EINVAL;
236 
237 	do {
238 		enum ci13xxx_regs reg = OP_ENDPTCTRL + num;
239 		u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
240 		u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
241 
242 		/* data toggle - reserved for EP0 but it's in ESS */
243 		hw_write(ci, reg, mask_xs|mask_xr,
244 			  value ? mask_xs : mask_xr);
245 	} while (value != hw_ep_get_halt(ci, num, dir));
246 
247 	return 0;
248 }
249 
250 /**
251  * hw_is_port_high_speed: test if port is high speed
252  *
253  * This function returns true if high speed port
254  */
255 static int hw_port_is_high_speed(struct ci13xxx *ci)
256 {
257 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
258 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
259 }
260 
261 /**
262  * hw_read_intr_enable: returns interrupt enable register
263  *
264  * This function returns register data
265  */
266 static u32 hw_read_intr_enable(struct ci13xxx *ci)
267 {
268 	return hw_read(ci, OP_USBINTR, ~0);
269 }
270 
271 /**
272  * hw_read_intr_status: returns interrupt status register
273  *
274  * This function returns register data
275  */
276 static u32 hw_read_intr_status(struct ci13xxx *ci)
277 {
278 	return hw_read(ci, OP_USBSTS, ~0);
279 }
280 
281 /**
282  * hw_test_and_clear_complete: test & clear complete status (execute without
283  *                             interruption)
284  * @n: endpoint number
285  *
286  * This function returns complete status
287  */
288 static int hw_test_and_clear_complete(struct ci13xxx *ci, int n)
289 {
290 	n = ep_to_bit(ci, n);
291 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
292 }
293 
294 /**
295  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
296  *                                without interruption)
297  *
298  * This function returns active interrutps
299  */
300 static u32 hw_test_and_clear_intr_active(struct ci13xxx *ci)
301 {
302 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
303 
304 	hw_write(ci, OP_USBSTS, ~0, reg);
305 	return reg;
306 }
307 
308 /**
309  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
310  *                                interruption)
311  *
312  * This function returns guard value
313  */
314 static int hw_test_and_clear_setup_guard(struct ci13xxx *ci)
315 {
316 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
317 }
318 
319 /**
320  * hw_test_and_set_setup_guard: test & set setup guard (execute without
321  *                              interruption)
322  *
323  * This function returns guard value
324  */
325 static int hw_test_and_set_setup_guard(struct ci13xxx *ci)
326 {
327 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
328 }
329 
330 /**
331  * hw_usb_set_address: configures USB address (execute without interruption)
332  * @value: new USB address
333  *
334  * This function explicitly sets the address, without the "USBADRA" (advance)
335  * feature, which is not supported by older versions of the controller.
336  */
337 static void hw_usb_set_address(struct ci13xxx *ci, u8 value)
338 {
339 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
340 		 value << ffs_nr(DEVICEADDR_USBADR));
341 }
342 
343 /**
344  * hw_usb_reset: restart device after a bus reset (execute without
345  *               interruption)
346  *
347  * This function returns an error code
348  */
349 static int hw_usb_reset(struct ci13xxx *ci)
350 {
351 	hw_usb_set_address(ci, 0);
352 
353 	/* ESS flushes only at end?!? */
354 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
355 
356 	/* clear setup token semaphores */
357 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
358 
359 	/* clear complete status */
360 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
361 
362 	/* wait until all bits cleared */
363 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
364 		udelay(10);             /* not RTOS friendly */
365 
366 	/* reset all endpoints ? */
367 
368 	/* reset internal status and wait for further instructions
369 	   no need to verify the port reset status (ESS does it) */
370 
371 	return 0;
372 }
373 
374 /******************************************************************************
375  * UTIL block
376  *****************************************************************************/
377 /**
378  * _usb_addr: calculates endpoint address from direction & number
379  * @ep:  endpoint
380  */
381 static inline u8 _usb_addr(struct ci13xxx_ep *ep)
382 {
383 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
384 }
385 
386 /**
387  * _hardware_queue: configures a request at hardware level
388  * @gadget: gadget
389  * @mEp:    endpoint
390  *
391  * This function returns an error code
392  */
393 static int _hardware_enqueue(struct ci13xxx_ep *mEp, struct ci13xxx_req *mReq)
394 {
395 	struct ci13xxx *ci = mEp->ci;
396 	unsigned i;
397 	int ret = 0;
398 	unsigned length = mReq->req.length;
399 
400 	/* don't queue twice */
401 	if (mReq->req.status == -EALREADY)
402 		return -EALREADY;
403 
404 	mReq->req.status = -EALREADY;
405 
406 	if (mReq->req.zero && length && (length % mEp->ep.maxpacket == 0)) {
407 		mReq->zptr = dma_pool_alloc(mEp->td_pool, GFP_ATOMIC,
408 					   &mReq->zdma);
409 		if (mReq->zptr == NULL)
410 			return -ENOMEM;
411 
412 		memset(mReq->zptr, 0, sizeof(*mReq->zptr));
413 		mReq->zptr->next    = TD_TERMINATE;
414 		mReq->zptr->token   = TD_STATUS_ACTIVE;
415 		if (!mReq->req.no_interrupt)
416 			mReq->zptr->token   |= TD_IOC;
417 	}
418 	ret = usb_gadget_map_request(&ci->gadget, &mReq->req, mEp->dir);
419 	if (ret)
420 		return ret;
421 
422 	/*
423 	 * TD configuration
424 	 * TODO - handle requests which spawns into several TDs
425 	 */
426 	memset(mReq->ptr, 0, sizeof(*mReq->ptr));
427 	mReq->ptr->token    = length << ffs_nr(TD_TOTAL_BYTES);
428 	mReq->ptr->token   &= TD_TOTAL_BYTES;
429 	mReq->ptr->token   |= TD_STATUS_ACTIVE;
430 	if (mReq->zptr) {
431 		mReq->ptr->next    = mReq->zdma;
432 	} else {
433 		mReq->ptr->next    = TD_TERMINATE;
434 		if (!mReq->req.no_interrupt)
435 			mReq->ptr->token  |= TD_IOC;
436 	}
437 	mReq->ptr->page[0]  = mReq->req.dma;
438 	for (i = 1; i < 5; i++)
439 		mReq->ptr->page[i] =
440 			(mReq->req.dma + i * CI13XXX_PAGE_SIZE) & ~TD_RESERVED_MASK;
441 
442 	if (!list_empty(&mEp->qh.queue)) {
443 		struct ci13xxx_req *mReqPrev;
444 		int n = hw_ep_bit(mEp->num, mEp->dir);
445 		int tmp_stat;
446 
447 		mReqPrev = list_entry(mEp->qh.queue.prev,
448 				struct ci13xxx_req, queue);
449 		if (mReqPrev->zptr)
450 			mReqPrev->zptr->next = mReq->dma & TD_ADDR_MASK;
451 		else
452 			mReqPrev->ptr->next = mReq->dma & TD_ADDR_MASK;
453 		wmb();
454 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
455 			goto done;
456 		do {
457 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
458 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
459 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
460 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
461 		if (tmp_stat)
462 			goto done;
463 	}
464 
465 	/*  QH configuration */
466 	mEp->qh.ptr->td.next   = mReq->dma;    /* TERMINATE = 0 */
467 	mEp->qh.ptr->td.token &= ~TD_STATUS;   /* clear status */
468 	mEp->qh.ptr->cap |=  QH_ZLT;
469 
470 	wmb();   /* synchronize before ep prime */
471 
472 	ret = hw_ep_prime(ci, mEp->num, mEp->dir,
473 			   mEp->type == USB_ENDPOINT_XFER_CONTROL);
474 done:
475 	return ret;
476 }
477 
478 /**
479  * _hardware_dequeue: handles a request at hardware level
480  * @gadget: gadget
481  * @mEp:    endpoint
482  *
483  * This function returns an error code
484  */
485 static int _hardware_dequeue(struct ci13xxx_ep *mEp, struct ci13xxx_req *mReq)
486 {
487 	if (mReq->req.status != -EALREADY)
488 		return -EINVAL;
489 
490 	if ((TD_STATUS_ACTIVE & mReq->ptr->token) != 0)
491 		return -EBUSY;
492 
493 	if (mReq->zptr) {
494 		if ((TD_STATUS_ACTIVE & mReq->zptr->token) != 0)
495 			return -EBUSY;
496 		dma_pool_free(mEp->td_pool, mReq->zptr, mReq->zdma);
497 		mReq->zptr = NULL;
498 	}
499 
500 	mReq->req.status = 0;
501 
502 	usb_gadget_unmap_request(&mEp->ci->gadget, &mReq->req, mEp->dir);
503 
504 	mReq->req.status = mReq->ptr->token & TD_STATUS;
505 	if ((TD_STATUS_HALTED & mReq->req.status) != 0)
506 		mReq->req.status = -1;
507 	else if ((TD_STATUS_DT_ERR & mReq->req.status) != 0)
508 		mReq->req.status = -1;
509 	else if ((TD_STATUS_TR_ERR & mReq->req.status) != 0)
510 		mReq->req.status = -1;
511 
512 	mReq->req.actual   = mReq->ptr->token & TD_TOTAL_BYTES;
513 	mReq->req.actual >>= ffs_nr(TD_TOTAL_BYTES);
514 	mReq->req.actual   = mReq->req.length - mReq->req.actual;
515 	mReq->req.actual   = mReq->req.status ? 0 : mReq->req.actual;
516 
517 	return mReq->req.actual;
518 }
519 
520 /**
521  * _ep_nuke: dequeues all endpoint requests
522  * @mEp: endpoint
523  *
524  * This function returns an error code
525  * Caller must hold lock
526  */
527 static int _ep_nuke(struct ci13xxx_ep *mEp)
528 __releases(mEp->lock)
529 __acquires(mEp->lock)
530 {
531 	if (mEp == NULL)
532 		return -EINVAL;
533 
534 	hw_ep_flush(mEp->ci, mEp->num, mEp->dir);
535 
536 	while (!list_empty(&mEp->qh.queue)) {
537 
538 		/* pop oldest request */
539 		struct ci13xxx_req *mReq = \
540 			list_entry(mEp->qh.queue.next,
541 				   struct ci13xxx_req, queue);
542 		list_del_init(&mReq->queue);
543 		mReq->req.status = -ESHUTDOWN;
544 
545 		if (mReq->req.complete != NULL) {
546 			spin_unlock(mEp->lock);
547 			mReq->req.complete(&mEp->ep, &mReq->req);
548 			spin_lock(mEp->lock);
549 		}
550 	}
551 	return 0;
552 }
553 
554 /**
555  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
556  * @gadget: gadget
557  *
558  * This function returns an error code
559  */
560 static int _gadget_stop_activity(struct usb_gadget *gadget)
561 {
562 	struct usb_ep *ep;
563 	struct ci13xxx    *ci = container_of(gadget, struct ci13xxx, gadget);
564 	unsigned long flags;
565 
566 	spin_lock_irqsave(&ci->lock, flags);
567 	ci->gadget.speed = USB_SPEED_UNKNOWN;
568 	ci->remote_wakeup = 0;
569 	ci->suspended = 0;
570 	spin_unlock_irqrestore(&ci->lock, flags);
571 
572 	/* flush all endpoints */
573 	gadget_for_each_ep(ep, gadget) {
574 		usb_ep_fifo_flush(ep);
575 	}
576 	usb_ep_fifo_flush(&ci->ep0out->ep);
577 	usb_ep_fifo_flush(&ci->ep0in->ep);
578 
579 	if (ci->driver)
580 		ci->driver->disconnect(gadget);
581 
582 	/* make sure to disable all endpoints */
583 	gadget_for_each_ep(ep, gadget) {
584 		usb_ep_disable(ep);
585 	}
586 
587 	if (ci->status != NULL) {
588 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
589 		ci->status = NULL;
590 	}
591 
592 	return 0;
593 }
594 
595 /******************************************************************************
596  * ISR block
597  *****************************************************************************/
598 /**
599  * isr_reset_handler: USB reset interrupt handler
600  * @ci: UDC device
601  *
602  * This function resets USB engine after a bus reset occurred
603  */
604 static void isr_reset_handler(struct ci13xxx *ci)
605 __releases(ci->lock)
606 __acquires(ci->lock)
607 {
608 	int retval;
609 
610 	dbg_event(0xFF, "BUS RST", 0);
611 
612 	spin_unlock(&ci->lock);
613 	retval = _gadget_stop_activity(&ci->gadget);
614 	if (retval)
615 		goto done;
616 
617 	retval = hw_usb_reset(ci);
618 	if (retval)
619 		goto done;
620 
621 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
622 	if (ci->status == NULL)
623 		retval = -ENOMEM;
624 
625 done:
626 	spin_lock(&ci->lock);
627 
628 	if (retval)
629 		dev_err(ci->dev, "error: %i\n", retval);
630 }
631 
632 /**
633  * isr_get_status_complete: get_status request complete function
634  * @ep:  endpoint
635  * @req: request handled
636  *
637  * Caller must release lock
638  */
639 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
640 {
641 	if (ep == NULL || req == NULL)
642 		return;
643 
644 	kfree(req->buf);
645 	usb_ep_free_request(ep, req);
646 }
647 
648 /**
649  * isr_get_status_response: get_status request response
650  * @ci: ci struct
651  * @setup: setup request packet
652  *
653  * This function returns an error code
654  */
655 static int isr_get_status_response(struct ci13xxx *ci,
656 				   struct usb_ctrlrequest *setup)
657 __releases(mEp->lock)
658 __acquires(mEp->lock)
659 {
660 	struct ci13xxx_ep *mEp = ci->ep0in;
661 	struct usb_request *req = NULL;
662 	gfp_t gfp_flags = GFP_ATOMIC;
663 	int dir, num, retval;
664 
665 	if (mEp == NULL || setup == NULL)
666 		return -EINVAL;
667 
668 	spin_unlock(mEp->lock);
669 	req = usb_ep_alloc_request(&mEp->ep, gfp_flags);
670 	spin_lock(mEp->lock);
671 	if (req == NULL)
672 		return -ENOMEM;
673 
674 	req->complete = isr_get_status_complete;
675 	req->length   = 2;
676 	req->buf      = kzalloc(req->length, gfp_flags);
677 	if (req->buf == NULL) {
678 		retval = -ENOMEM;
679 		goto err_free_req;
680 	}
681 
682 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
683 		/* Assume that device is bus powered for now. */
684 		*(u16 *)req->buf = ci->remote_wakeup << 1;
685 		retval = 0;
686 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
687 		   == USB_RECIP_ENDPOINT) {
688 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
689 			TX : RX;
690 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
691 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
692 	}
693 	/* else do nothing; reserved for future use */
694 
695 	spin_unlock(mEp->lock);
696 	retval = usb_ep_queue(&mEp->ep, req, gfp_flags);
697 	spin_lock(mEp->lock);
698 	if (retval)
699 		goto err_free_buf;
700 
701 	return 0;
702 
703  err_free_buf:
704 	kfree(req->buf);
705  err_free_req:
706 	spin_unlock(mEp->lock);
707 	usb_ep_free_request(&mEp->ep, req);
708 	spin_lock(mEp->lock);
709 	return retval;
710 }
711 
712 /**
713  * isr_setup_status_complete: setup_status request complete function
714  * @ep:  endpoint
715  * @req: request handled
716  *
717  * Caller must release lock. Put the port in test mode if test mode
718  * feature is selected.
719  */
720 static void
721 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
722 {
723 	struct ci13xxx *ci = req->context;
724 	unsigned long flags;
725 
726 	if (ci->setaddr) {
727 		hw_usb_set_address(ci, ci->address);
728 		ci->setaddr = false;
729 	}
730 
731 	spin_lock_irqsave(&ci->lock, flags);
732 	if (ci->test_mode)
733 		hw_port_test_set(ci, ci->test_mode);
734 	spin_unlock_irqrestore(&ci->lock, flags);
735 }
736 
737 /**
738  * isr_setup_status_phase: queues the status phase of a setup transation
739  * @ci: ci struct
740  *
741  * This function returns an error code
742  */
743 static int isr_setup_status_phase(struct ci13xxx *ci)
744 __releases(mEp->lock)
745 __acquires(mEp->lock)
746 {
747 	int retval;
748 	struct ci13xxx_ep *mEp;
749 
750 	mEp = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
751 	ci->status->context = ci;
752 	ci->status->complete = isr_setup_status_complete;
753 
754 	spin_unlock(mEp->lock);
755 	retval = usb_ep_queue(&mEp->ep, ci->status, GFP_ATOMIC);
756 	spin_lock(mEp->lock);
757 
758 	return retval;
759 }
760 
761 /**
762  * isr_tr_complete_low: transaction complete low level handler
763  * @mEp: endpoint
764  *
765  * This function returns an error code
766  * Caller must hold lock
767  */
768 static int isr_tr_complete_low(struct ci13xxx_ep *mEp)
769 __releases(mEp->lock)
770 __acquires(mEp->lock)
771 {
772 	struct ci13xxx_req *mReq, *mReqTemp;
773 	struct ci13xxx_ep *mEpTemp = mEp;
774 	int retval = 0;
775 
776 	list_for_each_entry_safe(mReq, mReqTemp, &mEp->qh.queue,
777 			queue) {
778 		retval = _hardware_dequeue(mEp, mReq);
779 		if (retval < 0)
780 			break;
781 		list_del_init(&mReq->queue);
782 		dbg_done(_usb_addr(mEp), mReq->ptr->token, retval);
783 		if (mReq->req.complete != NULL) {
784 			spin_unlock(mEp->lock);
785 			if ((mEp->type == USB_ENDPOINT_XFER_CONTROL) &&
786 					mReq->req.length)
787 				mEpTemp = mEp->ci->ep0in;
788 			mReq->req.complete(&mEpTemp->ep, &mReq->req);
789 			spin_lock(mEp->lock);
790 		}
791 	}
792 
793 	if (retval == -EBUSY)
794 		retval = 0;
795 	if (retval < 0)
796 		dbg_event(_usb_addr(mEp), "DONE", retval);
797 
798 	return retval;
799 }
800 
801 /**
802  * isr_tr_complete_handler: transaction complete interrupt handler
803  * @ci: UDC descriptor
804  *
805  * This function handles traffic events
806  */
807 static void isr_tr_complete_handler(struct ci13xxx *ci)
808 __releases(ci->lock)
809 __acquires(ci->lock)
810 {
811 	unsigned i;
812 	u8 tmode = 0;
813 
814 	for (i = 0; i < ci->hw_ep_max; i++) {
815 		struct ci13xxx_ep *mEp  = &ci->ci13xxx_ep[i];
816 		int type, num, dir, err = -EINVAL;
817 		struct usb_ctrlrequest req;
818 
819 		if (mEp->ep.desc == NULL)
820 			continue;   /* not configured */
821 
822 		if (hw_test_and_clear_complete(ci, i)) {
823 			err = isr_tr_complete_low(mEp);
824 			if (mEp->type == USB_ENDPOINT_XFER_CONTROL) {
825 				if (err > 0)   /* needs status phase */
826 					err = isr_setup_status_phase(ci);
827 				if (err < 0) {
828 					dbg_event(_usb_addr(mEp),
829 						  "ERROR", err);
830 					spin_unlock(&ci->lock);
831 					if (usb_ep_set_halt(&mEp->ep))
832 						dev_err(ci->dev,
833 							"error: ep_set_halt\n");
834 					spin_lock(&ci->lock);
835 				}
836 			}
837 		}
838 
839 		if (mEp->type != USB_ENDPOINT_XFER_CONTROL ||
840 		    !hw_test_and_clear_setup_status(ci, i))
841 			continue;
842 
843 		if (i != 0) {
844 			dev_warn(ci->dev, "ctrl traffic at endpoint %d\n", i);
845 			continue;
846 		}
847 
848 		/*
849 		 * Flush data and handshake transactions of previous
850 		 * setup packet.
851 		 */
852 		_ep_nuke(ci->ep0out);
853 		_ep_nuke(ci->ep0in);
854 
855 		/* read_setup_packet */
856 		do {
857 			hw_test_and_set_setup_guard(ci);
858 			memcpy(&req, &mEp->qh.ptr->setup, sizeof(req));
859 		} while (!hw_test_and_clear_setup_guard(ci));
860 
861 		type = req.bRequestType;
862 
863 		ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
864 
865 		dbg_setup(_usb_addr(mEp), &req);
866 
867 		switch (req.bRequest) {
868 		case USB_REQ_CLEAR_FEATURE:
869 			if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
870 					le16_to_cpu(req.wValue) ==
871 					USB_ENDPOINT_HALT) {
872 				if (req.wLength != 0)
873 					break;
874 				num  = le16_to_cpu(req.wIndex);
875 				dir = num & USB_ENDPOINT_DIR_MASK;
876 				num &= USB_ENDPOINT_NUMBER_MASK;
877 				if (dir) /* TX */
878 					num += ci->hw_ep_max/2;
879 				if (!ci->ci13xxx_ep[num].wedge) {
880 					spin_unlock(&ci->lock);
881 					err = usb_ep_clear_halt(
882 						&ci->ci13xxx_ep[num].ep);
883 					spin_lock(&ci->lock);
884 					if (err)
885 						break;
886 				}
887 				err = isr_setup_status_phase(ci);
888 			} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
889 					le16_to_cpu(req.wValue) ==
890 					USB_DEVICE_REMOTE_WAKEUP) {
891 				if (req.wLength != 0)
892 					break;
893 				ci->remote_wakeup = 0;
894 				err = isr_setup_status_phase(ci);
895 			} else {
896 				goto delegate;
897 			}
898 			break;
899 		case USB_REQ_GET_STATUS:
900 			if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
901 			    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
902 			    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
903 				goto delegate;
904 			if (le16_to_cpu(req.wLength) != 2 ||
905 			    le16_to_cpu(req.wValue)  != 0)
906 				break;
907 			err = isr_get_status_response(ci, &req);
908 			break;
909 		case USB_REQ_SET_ADDRESS:
910 			if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
911 				goto delegate;
912 			if (le16_to_cpu(req.wLength) != 0 ||
913 			    le16_to_cpu(req.wIndex)  != 0)
914 				break;
915 			ci->address = (u8)le16_to_cpu(req.wValue);
916 			ci->setaddr = true;
917 			err = isr_setup_status_phase(ci);
918 			break;
919 		case USB_REQ_SET_FEATURE:
920 			if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
921 					le16_to_cpu(req.wValue) ==
922 					USB_ENDPOINT_HALT) {
923 				if (req.wLength != 0)
924 					break;
925 				num  = le16_to_cpu(req.wIndex);
926 				dir = num & USB_ENDPOINT_DIR_MASK;
927 				num &= USB_ENDPOINT_NUMBER_MASK;
928 				if (dir) /* TX */
929 					num += ci->hw_ep_max/2;
930 
931 				spin_unlock(&ci->lock);
932 				err = usb_ep_set_halt(&ci->ci13xxx_ep[num].ep);
933 				spin_lock(&ci->lock);
934 				if (!err)
935 					isr_setup_status_phase(ci);
936 			} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
937 				if (req.wLength != 0)
938 					break;
939 				switch (le16_to_cpu(req.wValue)) {
940 				case USB_DEVICE_REMOTE_WAKEUP:
941 					ci->remote_wakeup = 1;
942 					err = isr_setup_status_phase(ci);
943 					break;
944 				case USB_DEVICE_TEST_MODE:
945 					tmode = le16_to_cpu(req.wIndex) >> 8;
946 					switch (tmode) {
947 					case TEST_J:
948 					case TEST_K:
949 					case TEST_SE0_NAK:
950 					case TEST_PACKET:
951 					case TEST_FORCE_EN:
952 						ci->test_mode = tmode;
953 						err = isr_setup_status_phase(
954 								ci);
955 						break;
956 					default:
957 						break;
958 					}
959 				default:
960 					goto delegate;
961 				}
962 			} else {
963 				goto delegate;
964 			}
965 			break;
966 		default:
967 delegate:
968 			if (req.wLength == 0)   /* no data phase */
969 				ci->ep0_dir = TX;
970 
971 			spin_unlock(&ci->lock);
972 			err = ci->driver->setup(&ci->gadget, &req);
973 			spin_lock(&ci->lock);
974 			break;
975 		}
976 
977 		if (err < 0) {
978 			dbg_event(_usb_addr(mEp), "ERROR", err);
979 
980 			spin_unlock(&ci->lock);
981 			if (usb_ep_set_halt(&mEp->ep))
982 				dev_err(ci->dev, "error: ep_set_halt\n");
983 			spin_lock(&ci->lock);
984 		}
985 	}
986 }
987 
988 /******************************************************************************
989  * ENDPT block
990  *****************************************************************************/
991 /**
992  * ep_enable: configure endpoint, making it usable
993  *
994  * Check usb_ep_enable() at "usb_gadget.h" for details
995  */
996 static int ep_enable(struct usb_ep *ep,
997 		     const struct usb_endpoint_descriptor *desc)
998 {
999 	struct ci13xxx_ep *mEp = container_of(ep, struct ci13xxx_ep, ep);
1000 	int retval = 0;
1001 	unsigned long flags;
1002 
1003 	if (ep == NULL || desc == NULL)
1004 		return -EINVAL;
1005 
1006 	spin_lock_irqsave(mEp->lock, flags);
1007 
1008 	/* only internal SW should enable ctrl endpts */
1009 
1010 	mEp->ep.desc = desc;
1011 
1012 	if (!list_empty(&mEp->qh.queue))
1013 		dev_warn(mEp->ci->dev, "enabling a non-empty endpoint!\n");
1014 
1015 	mEp->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1016 	mEp->num  = usb_endpoint_num(desc);
1017 	mEp->type = usb_endpoint_type(desc);
1018 
1019 	mEp->ep.maxpacket = usb_endpoint_maxp(desc);
1020 
1021 	dbg_event(_usb_addr(mEp), "ENABLE", 0);
1022 
1023 	mEp->qh.ptr->cap = 0;
1024 
1025 	if (mEp->type == USB_ENDPOINT_XFER_CONTROL)
1026 		mEp->qh.ptr->cap |=  QH_IOS;
1027 	else if (mEp->type == USB_ENDPOINT_XFER_ISOC)
1028 		mEp->qh.ptr->cap &= ~QH_MULT;
1029 	else
1030 		mEp->qh.ptr->cap &= ~QH_ZLT;
1031 
1032 	mEp->qh.ptr->cap |=
1033 		(mEp->ep.maxpacket << ffs_nr(QH_MAX_PKT)) & QH_MAX_PKT;
1034 	mEp->qh.ptr->td.next |= TD_TERMINATE;   /* needed? */
1035 
1036 	/*
1037 	 * Enable endpoints in the HW other than ep0 as ep0
1038 	 * is always enabled
1039 	 */
1040 	if (mEp->num)
1041 		retval |= hw_ep_enable(mEp->ci, mEp->num, mEp->dir, mEp->type);
1042 
1043 	spin_unlock_irqrestore(mEp->lock, flags);
1044 	return retval;
1045 }
1046 
1047 /**
1048  * ep_disable: endpoint is no longer usable
1049  *
1050  * Check usb_ep_disable() at "usb_gadget.h" for details
1051  */
1052 static int ep_disable(struct usb_ep *ep)
1053 {
1054 	struct ci13xxx_ep *mEp = container_of(ep, struct ci13xxx_ep, ep);
1055 	int direction, retval = 0;
1056 	unsigned long flags;
1057 
1058 	if (ep == NULL)
1059 		return -EINVAL;
1060 	else if (mEp->ep.desc == NULL)
1061 		return -EBUSY;
1062 
1063 	spin_lock_irqsave(mEp->lock, flags);
1064 
1065 	/* only internal SW should disable ctrl endpts */
1066 
1067 	direction = mEp->dir;
1068 	do {
1069 		dbg_event(_usb_addr(mEp), "DISABLE", 0);
1070 
1071 		retval |= _ep_nuke(mEp);
1072 		retval |= hw_ep_disable(mEp->ci, mEp->num, mEp->dir);
1073 
1074 		if (mEp->type == USB_ENDPOINT_XFER_CONTROL)
1075 			mEp->dir = (mEp->dir == TX) ? RX : TX;
1076 
1077 	} while (mEp->dir != direction);
1078 
1079 	mEp->ep.desc = NULL;
1080 
1081 	spin_unlock_irqrestore(mEp->lock, flags);
1082 	return retval;
1083 }
1084 
1085 /**
1086  * ep_alloc_request: allocate a request object to use with this endpoint
1087  *
1088  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1089  */
1090 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1091 {
1092 	struct ci13xxx_ep  *mEp  = container_of(ep, struct ci13xxx_ep, ep);
1093 	struct ci13xxx_req *mReq = NULL;
1094 
1095 	if (ep == NULL)
1096 		return NULL;
1097 
1098 	mReq = kzalloc(sizeof(struct ci13xxx_req), gfp_flags);
1099 	if (mReq != NULL) {
1100 		INIT_LIST_HEAD(&mReq->queue);
1101 
1102 		mReq->ptr = dma_pool_alloc(mEp->td_pool, gfp_flags,
1103 					   &mReq->dma);
1104 		if (mReq->ptr == NULL) {
1105 			kfree(mReq);
1106 			mReq = NULL;
1107 		}
1108 	}
1109 
1110 	dbg_event(_usb_addr(mEp), "ALLOC", mReq == NULL);
1111 
1112 	return (mReq == NULL) ? NULL : &mReq->req;
1113 }
1114 
1115 /**
1116  * ep_free_request: frees a request object
1117  *
1118  * Check usb_ep_free_request() at "usb_gadget.h" for details
1119  */
1120 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1121 {
1122 	struct ci13xxx_ep  *mEp  = container_of(ep,  struct ci13xxx_ep, ep);
1123 	struct ci13xxx_req *mReq = container_of(req, struct ci13xxx_req, req);
1124 	unsigned long flags;
1125 
1126 	if (ep == NULL || req == NULL) {
1127 		return;
1128 	} else if (!list_empty(&mReq->queue)) {
1129 		dev_err(mEp->ci->dev, "freeing queued request\n");
1130 		return;
1131 	}
1132 
1133 	spin_lock_irqsave(mEp->lock, flags);
1134 
1135 	if (mReq->ptr)
1136 		dma_pool_free(mEp->td_pool, mReq->ptr, mReq->dma);
1137 	kfree(mReq);
1138 
1139 	dbg_event(_usb_addr(mEp), "FREE", 0);
1140 
1141 	spin_unlock_irqrestore(mEp->lock, flags);
1142 }
1143 
1144 /**
1145  * ep_queue: queues (submits) an I/O request to an endpoint
1146  *
1147  * Check usb_ep_queue()* at usb_gadget.h" for details
1148  */
1149 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1150 		    gfp_t __maybe_unused gfp_flags)
1151 {
1152 	struct ci13xxx_ep  *mEp  = container_of(ep,  struct ci13xxx_ep, ep);
1153 	struct ci13xxx_req *mReq = container_of(req, struct ci13xxx_req, req);
1154 	struct ci13xxx *ci = mEp->ci;
1155 	int retval = 0;
1156 	unsigned long flags;
1157 
1158 	if (ep == NULL || req == NULL || mEp->ep.desc == NULL)
1159 		return -EINVAL;
1160 
1161 	spin_lock_irqsave(mEp->lock, flags);
1162 
1163 	if (mEp->type == USB_ENDPOINT_XFER_CONTROL) {
1164 		if (req->length)
1165 			mEp = (ci->ep0_dir == RX) ?
1166 			       ci->ep0out : ci->ep0in;
1167 		if (!list_empty(&mEp->qh.queue)) {
1168 			_ep_nuke(mEp);
1169 			retval = -EOVERFLOW;
1170 			dev_warn(mEp->ci->dev, "endpoint ctrl %X nuked\n",
1171 				 _usb_addr(mEp));
1172 		}
1173 	}
1174 
1175 	/* first nuke then test link, e.g. previous status has not sent */
1176 	if (!list_empty(&mReq->queue)) {
1177 		retval = -EBUSY;
1178 		dev_err(mEp->ci->dev, "request already in queue\n");
1179 		goto done;
1180 	}
1181 
1182 	if (req->length > 4 * CI13XXX_PAGE_SIZE) {
1183 		req->length = 4 * CI13XXX_PAGE_SIZE;
1184 		retval = -EMSGSIZE;
1185 		dev_warn(mEp->ci->dev, "request length truncated\n");
1186 	}
1187 
1188 	dbg_queue(_usb_addr(mEp), req, retval);
1189 
1190 	/* push request */
1191 	mReq->req.status = -EINPROGRESS;
1192 	mReq->req.actual = 0;
1193 
1194 	retval = _hardware_enqueue(mEp, mReq);
1195 
1196 	if (retval == -EALREADY) {
1197 		dbg_event(_usb_addr(mEp), "QUEUE", retval);
1198 		retval = 0;
1199 	}
1200 	if (!retval)
1201 		list_add_tail(&mReq->queue, &mEp->qh.queue);
1202 
1203  done:
1204 	spin_unlock_irqrestore(mEp->lock, flags);
1205 	return retval;
1206 }
1207 
1208 /**
1209  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1210  *
1211  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1212  */
1213 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1214 {
1215 	struct ci13xxx_ep  *mEp  = container_of(ep,  struct ci13xxx_ep, ep);
1216 	struct ci13xxx_req *mReq = container_of(req, struct ci13xxx_req, req);
1217 	unsigned long flags;
1218 
1219 	if (ep == NULL || req == NULL || mReq->req.status != -EALREADY ||
1220 		mEp->ep.desc == NULL || list_empty(&mReq->queue) ||
1221 		list_empty(&mEp->qh.queue))
1222 		return -EINVAL;
1223 
1224 	spin_lock_irqsave(mEp->lock, flags);
1225 
1226 	dbg_event(_usb_addr(mEp), "DEQUEUE", 0);
1227 
1228 	hw_ep_flush(mEp->ci, mEp->num, mEp->dir);
1229 
1230 	/* pop request */
1231 	list_del_init(&mReq->queue);
1232 
1233 	usb_gadget_unmap_request(&mEp->ci->gadget, req, mEp->dir);
1234 
1235 	req->status = -ECONNRESET;
1236 
1237 	if (mReq->req.complete != NULL) {
1238 		spin_unlock(mEp->lock);
1239 		mReq->req.complete(&mEp->ep, &mReq->req);
1240 		spin_lock(mEp->lock);
1241 	}
1242 
1243 	spin_unlock_irqrestore(mEp->lock, flags);
1244 	return 0;
1245 }
1246 
1247 /**
1248  * ep_set_halt: sets the endpoint halt feature
1249  *
1250  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1251  */
1252 static int ep_set_halt(struct usb_ep *ep, int value)
1253 {
1254 	struct ci13xxx_ep *mEp = container_of(ep, struct ci13xxx_ep, ep);
1255 	int direction, retval = 0;
1256 	unsigned long flags;
1257 
1258 	if (ep == NULL || mEp->ep.desc == NULL)
1259 		return -EINVAL;
1260 
1261 	spin_lock_irqsave(mEp->lock, flags);
1262 
1263 #ifndef STALL_IN
1264 	/* g_file_storage MS compliant but g_zero fails chapter 9 compliance */
1265 	if (value && mEp->type == USB_ENDPOINT_XFER_BULK && mEp->dir == TX &&
1266 	    !list_empty(&mEp->qh.queue)) {
1267 		spin_unlock_irqrestore(mEp->lock, flags);
1268 		return -EAGAIN;
1269 	}
1270 #endif
1271 
1272 	direction = mEp->dir;
1273 	do {
1274 		dbg_event(_usb_addr(mEp), "HALT", value);
1275 		retval |= hw_ep_set_halt(mEp->ci, mEp->num, mEp->dir, value);
1276 
1277 		if (!value)
1278 			mEp->wedge = 0;
1279 
1280 		if (mEp->type == USB_ENDPOINT_XFER_CONTROL)
1281 			mEp->dir = (mEp->dir == TX) ? RX : TX;
1282 
1283 	} while (mEp->dir != direction);
1284 
1285 	spin_unlock_irqrestore(mEp->lock, flags);
1286 	return retval;
1287 }
1288 
1289 /**
1290  * ep_set_wedge: sets the halt feature and ignores clear requests
1291  *
1292  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1293  */
1294 static int ep_set_wedge(struct usb_ep *ep)
1295 {
1296 	struct ci13xxx_ep *mEp = container_of(ep, struct ci13xxx_ep, ep);
1297 	unsigned long flags;
1298 
1299 	if (ep == NULL || mEp->ep.desc == NULL)
1300 		return -EINVAL;
1301 
1302 	spin_lock_irqsave(mEp->lock, flags);
1303 
1304 	dbg_event(_usb_addr(mEp), "WEDGE", 0);
1305 	mEp->wedge = 1;
1306 
1307 	spin_unlock_irqrestore(mEp->lock, flags);
1308 
1309 	return usb_ep_set_halt(ep);
1310 }
1311 
1312 /**
1313  * ep_fifo_flush: flushes contents of a fifo
1314  *
1315  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1316  */
1317 static void ep_fifo_flush(struct usb_ep *ep)
1318 {
1319 	struct ci13xxx_ep *mEp = container_of(ep, struct ci13xxx_ep, ep);
1320 	unsigned long flags;
1321 
1322 	if (ep == NULL) {
1323 		dev_err(mEp->ci->dev, "%02X: -EINVAL\n", _usb_addr(mEp));
1324 		return;
1325 	}
1326 
1327 	spin_lock_irqsave(mEp->lock, flags);
1328 
1329 	dbg_event(_usb_addr(mEp), "FFLUSH", 0);
1330 	hw_ep_flush(mEp->ci, mEp->num, mEp->dir);
1331 
1332 	spin_unlock_irqrestore(mEp->lock, flags);
1333 }
1334 
1335 /**
1336  * Endpoint-specific part of the API to the USB controller hardware
1337  * Check "usb_gadget.h" for details
1338  */
1339 static const struct usb_ep_ops usb_ep_ops = {
1340 	.enable	       = ep_enable,
1341 	.disable       = ep_disable,
1342 	.alloc_request = ep_alloc_request,
1343 	.free_request  = ep_free_request,
1344 	.queue	       = ep_queue,
1345 	.dequeue       = ep_dequeue,
1346 	.set_halt      = ep_set_halt,
1347 	.set_wedge     = ep_set_wedge,
1348 	.fifo_flush    = ep_fifo_flush,
1349 };
1350 
1351 /******************************************************************************
1352  * GADGET block
1353  *****************************************************************************/
1354 static int ci13xxx_vbus_session(struct usb_gadget *_gadget, int is_active)
1355 {
1356 	struct ci13xxx *ci = container_of(_gadget, struct ci13xxx, gadget);
1357 	unsigned long flags;
1358 	int gadget_ready = 0;
1359 
1360 	if (!(ci->platdata->flags & CI13XXX_PULLUP_ON_VBUS))
1361 		return -EOPNOTSUPP;
1362 
1363 	spin_lock_irqsave(&ci->lock, flags);
1364 	ci->vbus_active = is_active;
1365 	if (ci->driver)
1366 		gadget_ready = 1;
1367 	spin_unlock_irqrestore(&ci->lock, flags);
1368 
1369 	if (gadget_ready) {
1370 		if (is_active) {
1371 			pm_runtime_get_sync(&_gadget->dev);
1372 			hw_device_reset(ci, USBMODE_CM_DC);
1373 			hw_device_state(ci, ci->ep0out->qh.dma);
1374 		} else {
1375 			hw_device_state(ci, 0);
1376 			if (ci->platdata->notify_event)
1377 				ci->platdata->notify_event(ci,
1378 				CI13XXX_CONTROLLER_STOPPED_EVENT);
1379 			_gadget_stop_activity(&ci->gadget);
1380 			pm_runtime_put_sync(&_gadget->dev);
1381 		}
1382 	}
1383 
1384 	return 0;
1385 }
1386 
1387 static int ci13xxx_wakeup(struct usb_gadget *_gadget)
1388 {
1389 	struct ci13xxx *ci = container_of(_gadget, struct ci13xxx, gadget);
1390 	unsigned long flags;
1391 	int ret = 0;
1392 
1393 	spin_lock_irqsave(&ci->lock, flags);
1394 	if (!ci->remote_wakeup) {
1395 		ret = -EOPNOTSUPP;
1396 		goto out;
1397 	}
1398 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1399 		ret = -EINVAL;
1400 		goto out;
1401 	}
1402 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1403 out:
1404 	spin_unlock_irqrestore(&ci->lock, flags);
1405 	return ret;
1406 }
1407 
1408 static int ci13xxx_vbus_draw(struct usb_gadget *_gadget, unsigned mA)
1409 {
1410 	struct ci13xxx *ci = container_of(_gadget, struct ci13xxx, gadget);
1411 
1412 	if (ci->transceiver)
1413 		return usb_phy_set_power(ci->transceiver, mA);
1414 	return -ENOTSUPP;
1415 }
1416 
1417 /* Change Data+ pullup status
1418  * this func is used by usb_gadget_connect/disconnet
1419  */
1420 static int ci13xxx_pullup(struct usb_gadget *_gadget, int is_on)
1421 {
1422 	struct ci13xxx *ci = container_of(_gadget, struct ci13xxx, gadget);
1423 
1424 	if (is_on)
1425 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1426 	else
1427 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1428 
1429 	return 0;
1430 }
1431 
1432 static int ci13xxx_start(struct usb_gadget *gadget,
1433 			 struct usb_gadget_driver *driver);
1434 static int ci13xxx_stop(struct usb_gadget *gadget,
1435 			struct usb_gadget_driver *driver);
1436 /**
1437  * Device operations part of the API to the USB controller hardware,
1438  * which don't involve endpoints (or i/o)
1439  * Check  "usb_gadget.h" for details
1440  */
1441 static const struct usb_gadget_ops usb_gadget_ops = {
1442 	.vbus_session	= ci13xxx_vbus_session,
1443 	.wakeup		= ci13xxx_wakeup,
1444 	.pullup		= ci13xxx_pullup,
1445 	.vbus_draw	= ci13xxx_vbus_draw,
1446 	.udc_start	= ci13xxx_start,
1447 	.udc_stop	= ci13xxx_stop,
1448 };
1449 
1450 static int init_eps(struct ci13xxx *ci)
1451 {
1452 	int retval = 0, i, j;
1453 
1454 	for (i = 0; i < ci->hw_ep_max/2; i++)
1455 		for (j = RX; j <= TX; j++) {
1456 			int k = i + j * ci->hw_ep_max/2;
1457 			struct ci13xxx_ep *mEp = &ci->ci13xxx_ep[k];
1458 
1459 			scnprintf(mEp->name, sizeof(mEp->name), "ep%i%s", i,
1460 					(j == TX)  ? "in" : "out");
1461 
1462 			mEp->ci          = ci;
1463 			mEp->lock         = &ci->lock;
1464 			mEp->td_pool      = ci->td_pool;
1465 
1466 			mEp->ep.name      = mEp->name;
1467 			mEp->ep.ops       = &usb_ep_ops;
1468 			/*
1469 			 * for ep0: maxP defined in desc, for other
1470 			 * eps, maxP is set by epautoconfig() called
1471 			 * by gadget layer
1472 			 */
1473 			mEp->ep.maxpacket = (unsigned short)~0;
1474 
1475 			INIT_LIST_HEAD(&mEp->qh.queue);
1476 			mEp->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1477 						     &mEp->qh.dma);
1478 			if (mEp->qh.ptr == NULL)
1479 				retval = -ENOMEM;
1480 			else
1481 				memset(mEp->qh.ptr, 0, sizeof(*mEp->qh.ptr));
1482 
1483 			/*
1484 			 * set up shorthands for ep0 out and in endpoints,
1485 			 * don't add to gadget's ep_list
1486 			 */
1487 			if (i == 0) {
1488 				if (j == RX)
1489 					ci->ep0out = mEp;
1490 				else
1491 					ci->ep0in = mEp;
1492 
1493 				mEp->ep.maxpacket = CTRL_PAYLOAD_MAX;
1494 				continue;
1495 			}
1496 
1497 			list_add_tail(&mEp->ep.ep_list, &ci->gadget.ep_list);
1498 		}
1499 
1500 	return retval;
1501 }
1502 
1503 static void destroy_eps(struct ci13xxx *ci)
1504 {
1505 	int i;
1506 
1507 	for (i = 0; i < ci->hw_ep_max; i++) {
1508 		struct ci13xxx_ep *mEp = &ci->ci13xxx_ep[i];
1509 
1510 		dma_pool_free(ci->qh_pool, mEp->qh.ptr, mEp->qh.dma);
1511 	}
1512 }
1513 
1514 /**
1515  * ci13xxx_start: register a gadget driver
1516  * @gadget: our gadget
1517  * @driver: the driver being registered
1518  *
1519  * Interrupts are enabled here.
1520  */
1521 static int ci13xxx_start(struct usb_gadget *gadget,
1522 			 struct usb_gadget_driver *driver)
1523 {
1524 	struct ci13xxx *ci = container_of(gadget, struct ci13xxx, gadget);
1525 	unsigned long flags;
1526 	int retval = -ENOMEM;
1527 
1528 	if (driver->disconnect == NULL)
1529 		return -EINVAL;
1530 
1531 
1532 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1533 	retval = usb_ep_enable(&ci->ep0out->ep);
1534 	if (retval)
1535 		return retval;
1536 
1537 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1538 	retval = usb_ep_enable(&ci->ep0in->ep);
1539 	if (retval)
1540 		return retval;
1541 	spin_lock_irqsave(&ci->lock, flags);
1542 
1543 	ci->driver = driver;
1544 	pm_runtime_get_sync(&ci->gadget.dev);
1545 	if (ci->platdata->flags & CI13XXX_PULLUP_ON_VBUS) {
1546 		if (ci->vbus_active) {
1547 			if (ci->platdata->flags & CI13XXX_REGS_SHARED)
1548 				hw_device_reset(ci, USBMODE_CM_DC);
1549 		} else {
1550 			pm_runtime_put_sync(&ci->gadget.dev);
1551 			goto done;
1552 		}
1553 	}
1554 
1555 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1556 	if (retval)
1557 		pm_runtime_put_sync(&ci->gadget.dev);
1558 
1559  done:
1560 	spin_unlock_irqrestore(&ci->lock, flags);
1561 	return retval;
1562 }
1563 
1564 /**
1565  * ci13xxx_stop: unregister a gadget driver
1566  */
1567 static int ci13xxx_stop(struct usb_gadget *gadget,
1568 			struct usb_gadget_driver *driver)
1569 {
1570 	struct ci13xxx *ci = container_of(gadget, struct ci13xxx, gadget);
1571 	unsigned long flags;
1572 
1573 	spin_lock_irqsave(&ci->lock, flags);
1574 
1575 	if (!(ci->platdata->flags & CI13XXX_PULLUP_ON_VBUS) ||
1576 			ci->vbus_active) {
1577 		hw_device_state(ci, 0);
1578 		if (ci->platdata->notify_event)
1579 			ci->platdata->notify_event(ci,
1580 			CI13XXX_CONTROLLER_STOPPED_EVENT);
1581 		ci->driver = NULL;
1582 		spin_unlock_irqrestore(&ci->lock, flags);
1583 		_gadget_stop_activity(&ci->gadget);
1584 		spin_lock_irqsave(&ci->lock, flags);
1585 		pm_runtime_put(&ci->gadget.dev);
1586 	}
1587 
1588 	spin_unlock_irqrestore(&ci->lock, flags);
1589 
1590 	return 0;
1591 }
1592 
1593 /******************************************************************************
1594  * BUS block
1595  *****************************************************************************/
1596 /**
1597  * udc_irq: ci interrupt handler
1598  *
1599  * This function returns IRQ_HANDLED if the IRQ has been handled
1600  * It locks access to registers
1601  */
1602 static irqreturn_t udc_irq(struct ci13xxx *ci)
1603 {
1604 	irqreturn_t retval;
1605 	u32 intr;
1606 
1607 	if (ci == NULL)
1608 		return IRQ_HANDLED;
1609 
1610 	spin_lock(&ci->lock);
1611 
1612 	if (ci->platdata->flags & CI13XXX_REGS_SHARED) {
1613 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1614 				USBMODE_CM_DC) {
1615 			spin_unlock(&ci->lock);
1616 			return IRQ_NONE;
1617 		}
1618 	}
1619 	intr = hw_test_and_clear_intr_active(ci);
1620 	dbg_interrupt(intr);
1621 
1622 	if (intr) {
1623 		/* order defines priority - do NOT change it */
1624 		if (USBi_URI & intr)
1625 			isr_reset_handler(ci);
1626 
1627 		if (USBi_PCI & intr) {
1628 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1629 				USB_SPEED_HIGH : USB_SPEED_FULL;
1630 			if (ci->suspended && ci->driver->resume) {
1631 				spin_unlock(&ci->lock);
1632 				ci->driver->resume(&ci->gadget);
1633 				spin_lock(&ci->lock);
1634 				ci->suspended = 0;
1635 			}
1636 		}
1637 
1638 		if (USBi_UI  & intr)
1639 			isr_tr_complete_handler(ci);
1640 
1641 		if (USBi_SLI & intr) {
1642 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1643 			    ci->driver->suspend) {
1644 				ci->suspended = 1;
1645 				spin_unlock(&ci->lock);
1646 				ci->driver->suspend(&ci->gadget);
1647 				spin_lock(&ci->lock);
1648 			}
1649 		}
1650 		retval = IRQ_HANDLED;
1651 	} else {
1652 		retval = IRQ_NONE;
1653 	}
1654 	spin_unlock(&ci->lock);
1655 
1656 	return retval;
1657 }
1658 
1659 /**
1660  * udc_release: driver release function
1661  * @dev: device
1662  *
1663  * Currently does nothing
1664  */
1665 static void udc_release(struct device *dev)
1666 {
1667 }
1668 
1669 /**
1670  * udc_start: initialize gadget role
1671  * @ci: chipidea controller
1672  */
1673 static int udc_start(struct ci13xxx *ci)
1674 {
1675 	struct device *dev = ci->dev;
1676 	int retval = 0;
1677 
1678 	spin_lock_init(&ci->lock);
1679 
1680 	ci->gadget.ops          = &usb_gadget_ops;
1681 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1682 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1683 	ci->gadget.is_otg       = 0;
1684 	ci->gadget.name         = ci->platdata->name;
1685 
1686 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1687 
1688 	dev_set_name(&ci->gadget.dev, "gadget");
1689 	ci->gadget.dev.dma_mask = dev->dma_mask;
1690 	ci->gadget.dev.coherent_dma_mask = dev->coherent_dma_mask;
1691 	ci->gadget.dev.parent   = dev;
1692 	ci->gadget.dev.release  = udc_release;
1693 
1694 	/* alloc resources */
1695 	ci->qh_pool = dma_pool_create("ci13xxx_qh", dev,
1696 				       sizeof(struct ci13xxx_qh),
1697 				       64, CI13XXX_PAGE_SIZE);
1698 	if (ci->qh_pool == NULL)
1699 		return -ENOMEM;
1700 
1701 	ci->td_pool = dma_pool_create("ci13xxx_td", dev,
1702 				       sizeof(struct ci13xxx_td),
1703 				       64, CI13XXX_PAGE_SIZE);
1704 	if (ci->td_pool == NULL) {
1705 		retval = -ENOMEM;
1706 		goto free_qh_pool;
1707 	}
1708 
1709 	retval = init_eps(ci);
1710 	if (retval)
1711 		goto free_pools;
1712 
1713 	ci->gadget.ep0 = &ci->ep0in->ep;
1714 
1715 	if (ci->global_phy)
1716 		ci->transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
1717 
1718 	if (ci->platdata->flags & CI13XXX_REQUIRE_TRANSCEIVER) {
1719 		if (ci->transceiver == NULL) {
1720 			retval = -ENODEV;
1721 			goto destroy_eps;
1722 		}
1723 	}
1724 
1725 	if (!(ci->platdata->flags & CI13XXX_REGS_SHARED)) {
1726 		retval = hw_device_reset(ci, USBMODE_CM_DC);
1727 		if (retval)
1728 			goto put_transceiver;
1729 	}
1730 
1731 	retval = device_register(&ci->gadget.dev);
1732 	if (retval) {
1733 		put_device(&ci->gadget.dev);
1734 		goto put_transceiver;
1735 	}
1736 
1737 	retval = dbg_create_files(&ci->gadget.dev);
1738 	if (retval)
1739 		goto unreg_device;
1740 
1741 	if (!IS_ERR_OR_NULL(ci->transceiver)) {
1742 		retval = otg_set_peripheral(ci->transceiver->otg,
1743 						&ci->gadget);
1744 		if (retval)
1745 			goto remove_dbg;
1746 	}
1747 
1748 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1749 	if (retval)
1750 		goto remove_trans;
1751 
1752 	pm_runtime_no_callbacks(&ci->gadget.dev);
1753 	pm_runtime_enable(&ci->gadget.dev);
1754 
1755 	return retval;
1756 
1757 remove_trans:
1758 	if (!IS_ERR_OR_NULL(ci->transceiver)) {
1759 		otg_set_peripheral(ci->transceiver->otg, NULL);
1760 		if (ci->global_phy)
1761 			usb_put_phy(ci->transceiver);
1762 	}
1763 
1764 	dev_err(dev, "error = %i\n", retval);
1765 remove_dbg:
1766 	dbg_remove_files(&ci->gadget.dev);
1767 unreg_device:
1768 	device_unregister(&ci->gadget.dev);
1769 put_transceiver:
1770 	if (!IS_ERR_OR_NULL(ci->transceiver) && ci->global_phy)
1771 		usb_put_phy(ci->transceiver);
1772 destroy_eps:
1773 	destroy_eps(ci);
1774 free_pools:
1775 	dma_pool_destroy(ci->td_pool);
1776 free_qh_pool:
1777 	dma_pool_destroy(ci->qh_pool);
1778 	return retval;
1779 }
1780 
1781 /**
1782  * udc_remove: parent remove must call this to remove UDC
1783  *
1784  * No interrupts active, the IRQ has been released
1785  */
1786 static void udc_stop(struct ci13xxx *ci)
1787 {
1788 	if (ci == NULL)
1789 		return;
1790 
1791 	usb_del_gadget_udc(&ci->gadget);
1792 
1793 	destroy_eps(ci);
1794 
1795 	dma_pool_destroy(ci->td_pool);
1796 	dma_pool_destroy(ci->qh_pool);
1797 
1798 	if (!IS_ERR_OR_NULL(ci->transceiver)) {
1799 		otg_set_peripheral(ci->transceiver->otg, NULL);
1800 		if (ci->global_phy)
1801 			usb_put_phy(ci->transceiver);
1802 	}
1803 	dbg_remove_files(&ci->gadget.dev);
1804 	device_unregister(&ci->gadget.dev);
1805 	/* my kobject is dynamic, I swear! */
1806 	memset(&ci->gadget, 0, sizeof(ci->gadget));
1807 }
1808 
1809 /**
1810  * ci_hdrc_gadget_init - initialize device related bits
1811  * ci: the controller
1812  *
1813  * This function enables the gadget role, if the device is "device capable".
1814  */
1815 int ci_hdrc_gadget_init(struct ci13xxx *ci)
1816 {
1817 	struct ci_role_driver *rdrv;
1818 
1819 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1820 		return -ENXIO;
1821 
1822 	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1823 	if (!rdrv)
1824 		return -ENOMEM;
1825 
1826 	rdrv->start	= udc_start;
1827 	rdrv->stop	= udc_stop;
1828 	rdrv->irq	= udc_irq;
1829 	rdrv->name	= "gadget";
1830 	ci->roles[CI_ROLE_GADGET] = rdrv;
1831 
1832 	return 0;
1833 }
1834