1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * USB Peripheral Controller driver for Aeroflex Gaisler GRUSBDC.
4 *
5 * 2013 (c) Aeroflex Gaisler AB
6 *
7 * This driver supports GRUSBDC USB Device Controller cores available in the
8 * GRLIB VHDL IP core library.
9 *
10 * Full documentation of the GRUSBDC core can be found here:
11 * https://www.gaisler.com/products/grlib/grip.pdf
12 *
13 * Contributors:
14 * - Andreas Larsson <andreas@gaisler.com>
15 * - Marko Isomaki
16 */
17
18/*
19 * A GRUSBDC core can have up to 16 IN endpoints and 16 OUT endpoints each
20 * individually configurable to any of the four USB transfer types. This driver
21 * only supports cores in DMA mode.
22 */
23
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/platform_device.h>
27#include <linux/slab.h>
28#include <linux/spinlock.h>
29#include <linux/errno.h>
30#include <linux/list.h>
31#include <linux/interrupt.h>
32#include <linux/device.h>
33#include <linux/usb.h>
34#include <linux/usb/ch9.h>
35#include <linux/usb/gadget.h>
36#include <linux/dma-mapping.h>
37#include <linux/dmapool.h>
38#include <linux/debugfs.h>
39#include <linux/seq_file.h>
40#include <linux/of.h>
41
42#include <asm/byteorder.h>
43
44#include "gr_udc.h"
45
46#define	DRIVER_NAME	"gr_udc"
47#define	DRIVER_DESC	"Aeroflex Gaisler GRUSBDC USB Peripheral Controller"
48
49static const char driver_name[] = DRIVER_NAME;
50
51#define gr_read32(x) (ioread32be((x)))
52#define gr_write32(x, v) (iowrite32be((v), (x)))
53
54/* USB speed and corresponding string calculated from status register value */
55#define GR_SPEED(status) \
56	((status & GR_STATUS_SP) ? USB_SPEED_FULL : USB_SPEED_HIGH)
57#define GR_SPEED_STR(status) usb_speed_string(GR_SPEED(status))
58
59/* Size of hardware buffer calculated from epctrl register value */
60#define GR_BUFFER_SIZE(epctrl)					      \
61	((((epctrl) & GR_EPCTRL_BUFSZ_MASK) >> GR_EPCTRL_BUFSZ_POS) * \
62	 GR_EPCTRL_BUFSZ_SCALER)
63
64/* ---------------------------------------------------------------------- */
65/* Debug printout functionality */
66
67static const char * const gr_modestring[] = {"control", "iso", "bulk", "int"};
68
69static const char *gr_ep0state_string(enum gr_ep0state state)
70{
71	static const char *const names[] = {
72		[GR_EP0_DISCONNECT] = "disconnect",
73		[GR_EP0_SETUP] = "setup",
74		[GR_EP0_IDATA] = "idata",
75		[GR_EP0_ODATA] = "odata",
76		[GR_EP0_ISTATUS] = "istatus",
77		[GR_EP0_OSTATUS] = "ostatus",
78		[GR_EP0_STALL] = "stall",
79		[GR_EP0_SUSPEND] = "suspend",
80	};
81
82	if (state < 0 || state >= ARRAY_SIZE(names))
83		return "UNKNOWN";
84
85	return names[state];
86}
87
88#ifdef VERBOSE_DEBUG
89
90static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
91				struct gr_request *req)
92{
93	int buflen = ep->is_in ? req->req.length : req->req.actual;
94	int rowlen = 32;
95	int plen = min(rowlen, buflen);
96
97	dev_dbg(ep->dev->dev, "%s: 0x%p, %d bytes data%s:\n", str, req, buflen,
98		(buflen > plen ? " (truncated)" : ""));
99	print_hex_dump_debug("   ", DUMP_PREFIX_NONE,
100			     rowlen, 4, req->req.buf, plen, false);
101}
102
103static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
104			       u16 value, u16 index, u16 length)
105{
106	dev_vdbg(dev->dev, "REQ: %02x.%02x v%04x i%04x l%04x\n",
107		 type, request, value, index, length);
108}
109#else /* !VERBOSE_DEBUG */
110
111static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
112				struct gr_request *req) {}
113
114static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
115			       u16 value, u16 index, u16 length) {}
116
117#endif /* VERBOSE_DEBUG */
118
119/* ---------------------------------------------------------------------- */
120/* Debugfs functionality */
121
122#ifdef CONFIG_USB_GADGET_DEBUG_FS
123
124static void gr_seq_ep_show(struct seq_file *seq, struct gr_ep *ep)
125{
126	u32 epctrl = gr_read32(&ep->regs->epctrl);
127	u32 epstat = gr_read32(&ep->regs->epstat);
128	int mode = (epctrl & GR_EPCTRL_TT_MASK) >> GR_EPCTRL_TT_POS;
129	struct gr_request *req;
130
131	seq_printf(seq, "%s:\n", ep->ep.name);
132	seq_printf(seq, "  mode = %s\n", gr_modestring[mode]);
133	seq_printf(seq, "  halted: %d\n", !!(epctrl & GR_EPCTRL_EH));
134	seq_printf(seq, "  disabled: %d\n", !!(epctrl & GR_EPCTRL_ED));
135	seq_printf(seq, "  valid: %d\n", !!(epctrl & GR_EPCTRL_EV));
136	seq_printf(seq, "  dma_start = %d\n", ep->dma_start);
137	seq_printf(seq, "  stopped = %d\n", ep->stopped);
138	seq_printf(seq, "  wedged = %d\n", ep->wedged);
139	seq_printf(seq, "  callback = %d\n", ep->callback);
140	seq_printf(seq, "  maxpacket = %d\n", ep->ep.maxpacket);
141	seq_printf(seq, "  maxpacket_limit = %d\n", ep->ep.maxpacket_limit);
142	seq_printf(seq, "  bytes_per_buffer = %d\n", ep->bytes_per_buffer);
143	if (mode == 1 || mode == 3)
144		seq_printf(seq, "  nt = %d\n",
145			   (epctrl & GR_EPCTRL_NT_MASK) >> GR_EPCTRL_NT_POS);
146
147	seq_printf(seq, "  Buffer 0: %s %s%d\n",
148		   epstat & GR_EPSTAT_B0 ? "valid" : "invalid",
149		   epstat & GR_EPSTAT_BS ? " " : "selected ",
150		   (epstat & GR_EPSTAT_B0CNT_MASK) >> GR_EPSTAT_B0CNT_POS);
151	seq_printf(seq, "  Buffer 1: %s %s%d\n",
152		   epstat & GR_EPSTAT_B1 ? "valid" : "invalid",
153		   epstat & GR_EPSTAT_BS ? "selected " : " ",
154		   (epstat & GR_EPSTAT_B1CNT_MASK) >> GR_EPSTAT_B1CNT_POS);
155
156	if (list_empty(&ep->queue)) {
157		seq_puts(seq, "  Queue: empty\n\n");
158		return;
159	}
160
161	seq_puts(seq, "  Queue:\n");
162	list_for_each_entry(req, &ep->queue, queue) {
163		struct gr_dma_desc *desc;
164		struct gr_dma_desc *next;
165
166		seq_printf(seq, "    0x%p: 0x%p %d %d\n", req,
167			   &req->req.buf, req->req.actual, req->req.length);
168
169		next = req->first_desc;
170		do {
171			desc = next;
172			next = desc->next_desc;
173			seq_printf(seq, "    %c 0x%p (0x%08x): 0x%05x 0x%08x\n",
174				   desc == req->curr_desc ? 'c' : ' ',
175				   desc, desc->paddr, desc->ctrl, desc->data);
176		} while (desc != req->last_desc);
177	}
178	seq_puts(seq, "\n");
179}
180
181static int gr_dfs_show(struct seq_file *seq, void *v)
182{
183	struct gr_udc *dev = seq->private;
184	u32 control = gr_read32(&dev->regs->control);
185	u32 status = gr_read32(&dev->regs->status);
186	struct gr_ep *ep;
187
188	seq_printf(seq, "usb state = %s\n",
189		   usb_state_string(dev->gadget.state));
190	seq_printf(seq, "address = %d\n",
191		   (control & GR_CONTROL_UA_MASK) >> GR_CONTROL_UA_POS);
192	seq_printf(seq, "speed = %s\n", GR_SPEED_STR(status));
193	seq_printf(seq, "ep0state = %s\n", gr_ep0state_string(dev->ep0state));
194	seq_printf(seq, "irq_enabled = %d\n", dev->irq_enabled);
195	seq_printf(seq, "remote_wakeup = %d\n", dev->remote_wakeup);
196	seq_printf(seq, "test_mode = %d\n", dev->test_mode);
197	seq_puts(seq, "\n");
198
199	list_for_each_entry(ep, &dev->ep_list, ep_list)
200		gr_seq_ep_show(seq, ep);
201
202	return 0;
203}
204DEFINE_SHOW_ATTRIBUTE(gr_dfs);
205
206static void gr_dfs_create(struct gr_udc *dev)
207{
208	const char *name = "gr_udc_state";
209	struct dentry *root;
210
211	root = debugfs_create_dir(dev_name(dev->dev), usb_debug_root);
212	debugfs_create_file(name, 0444, root, dev, &gr_dfs_fops);
213}
214
215static void gr_dfs_delete(struct gr_udc *dev)
216{
217	debugfs_lookup_and_remove(dev_name(dev->dev), usb_debug_root);
218}
219
220#else /* !CONFIG_USB_GADGET_DEBUG_FS */
221
222static void gr_dfs_create(struct gr_udc *dev) {}
223static void gr_dfs_delete(struct gr_udc *dev) {}
224
225#endif /* CONFIG_USB_GADGET_DEBUG_FS */
226
227/* ---------------------------------------------------------------------- */
228/* DMA and request handling */
229
230/* Allocates a new struct gr_dma_desc, sets paddr and zeroes the rest */
231static struct gr_dma_desc *gr_alloc_dma_desc(struct gr_ep *ep, gfp_t gfp_flags)
232{
233	dma_addr_t paddr;
234	struct gr_dma_desc *dma_desc;
235
236	dma_desc = dma_pool_zalloc(ep->dev->desc_pool, gfp_flags, &paddr);
237	if (!dma_desc) {
238		dev_err(ep->dev->dev, "Could not allocate from DMA pool\n");
239		return NULL;
240	}
241
242	dma_desc->paddr = paddr;
243
244	return dma_desc;
245}
246
247static inline void gr_free_dma_desc(struct gr_udc *dev,
248				    struct gr_dma_desc *desc)
249{
250	dma_pool_free(dev->desc_pool, desc, (dma_addr_t)desc->paddr);
251}
252
253/* Frees the chain of struct gr_dma_desc for the given request */
254static void gr_free_dma_desc_chain(struct gr_udc *dev, struct gr_request *req)
255{
256	struct gr_dma_desc *desc;
257	struct gr_dma_desc *next;
258
259	next = req->first_desc;
260	if (!next)
261		return;
262
263	do {
264		desc = next;
265		next = desc->next_desc;
266		gr_free_dma_desc(dev, desc);
267	} while (desc != req->last_desc);
268
269	req->first_desc = NULL;
270	req->curr_desc = NULL;
271	req->last_desc = NULL;
272}
273
274static void gr_ep0_setup(struct gr_udc *dev, struct gr_request *req);
275
276/*
277 * Frees allocated resources and calls the appropriate completion function/setup
278 * package handler for a finished request.
279 *
280 * Must be called with dev->lock held and irqs disabled.
281 */
282static void gr_finish_request(struct gr_ep *ep, struct gr_request *req,
283			      int status)
284	__releases(&dev->lock)
285	__acquires(&dev->lock)
286{
287	struct gr_udc *dev;
288
289	list_del_init(&req->queue);
290
291	if (likely(req->req.status == -EINPROGRESS))
292		req->req.status = status;
293	else
294		status = req->req.status;
295
296	dev = ep->dev;
297	usb_gadget_unmap_request(&dev->gadget, &req->req, ep->is_in);
298	gr_free_dma_desc_chain(dev, req);
299
300	if (ep->is_in) { /* For OUT, req->req.actual gets updated bit by bit */
301		req->req.actual = req->req.length;
302	} else if (req->oddlen && req->req.actual > req->evenlen) {
303		/*
304		 * Copy to user buffer in this case where length was not evenly
305		 * divisible by ep->ep.maxpacket and the last descriptor was
306		 * actually used.
307		 */
308		char *buftail = ((char *)req->req.buf + req->evenlen);
309
310		memcpy(buftail, ep->tailbuf, req->oddlen);
311
312		if (req->req.actual > req->req.length) {
313			/* We got more data than was requested */
314			dev_dbg(ep->dev->dev, "Overflow for ep %s\n",
315				ep->ep.name);
316			gr_dbgprint_request("OVFL", ep, req);
317			req->req.status = -EOVERFLOW;
318		}
319	}
320
321	if (!status) {
322		if (ep->is_in)
323			gr_dbgprint_request("SENT", ep, req);
324		else
325			gr_dbgprint_request("RECV", ep, req);
326	}
327
328	/* Prevent changes to ep->queue during callback */
329	ep->callback = 1;
330	if (req == dev->ep0reqo && !status) {
331		if (req->setup)
332			gr_ep0_setup(dev, req);
333		else
334			dev_err(dev->dev,
335				"Unexpected non setup packet on ep0in\n");
336	} else if (req->req.complete) {
337		spin_unlock(&dev->lock);
338
339		usb_gadget_giveback_request(&ep->ep, &req->req);
340
341		spin_lock(&dev->lock);
342	}
343	ep->callback = 0;
344}
345
346static struct usb_request *gr_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
347{
348	struct gr_request *req;
349
350	req = kzalloc(sizeof(*req), gfp_flags);
351	if (!req)
352		return NULL;
353
354	INIT_LIST_HEAD(&req->queue);
355
356	return &req->req;
357}
358
359/*
360 * Starts DMA for endpoint ep if there are requests in the queue.
361 *
362 * Must be called with dev->lock held and with !ep->stopped.
363 */
364static void gr_start_dma(struct gr_ep *ep)
365{
366	struct gr_request *req;
367	u32 dmactrl;
368
369	if (list_empty(&ep->queue)) {
370		ep->dma_start = 0;
371		return;
372	}
373
374	req = list_first_entry(&ep->queue, struct gr_request, queue);
375
376	/* A descriptor should already have been allocated */
377	BUG_ON(!req->curr_desc);
378
379	/*
380	 * The DMA controller can not handle smaller OUT buffers than
381	 * ep->ep.maxpacket. It could lead to buffer overruns if an unexpectedly
382	 * long packet are received. Therefore an internal bounce buffer gets
383	 * used when such a request gets enabled.
384	 */
385	if (!ep->is_in && req->oddlen)
386		req->last_desc->data = ep->tailbuf_paddr;
387
388	wmb(); /* Make sure all is settled before handing it over to DMA */
389
390	/* Set the descriptor pointer in the hardware */
391	gr_write32(&ep->regs->dmaaddr, req->curr_desc->paddr);
392
393	/* Announce available descriptors */
394	dmactrl = gr_read32(&ep->regs->dmactrl);
395	gr_write32(&ep->regs->dmactrl, dmactrl | GR_DMACTRL_DA);
396
397	ep->dma_start = 1;
398}
399
400/*
401 * Finishes the first request in the ep's queue and, if available, starts the
402 * next request in queue.
403 *
404 * Must be called with dev->lock held, irqs disabled and with !ep->stopped.
405 */
406static void gr_dma_advance(struct gr_ep *ep, int status)
407{
408	struct gr_request *req;
409
410	req = list_first_entry(&ep->queue, struct gr_request, queue);
411	gr_finish_request(ep, req, status);
412	gr_start_dma(ep); /* Regardless of ep->dma_start */
413}
414
415/*
416 * Abort DMA for an endpoint. Sets the abort DMA bit which causes an ongoing DMA
417 * transfer to be canceled and clears GR_DMACTRL_DA.
418 *
419 * Must be called with dev->lock held.
420 */
421static void gr_abort_dma(struct gr_ep *ep)
422{
423	u32 dmactrl;
424
425	dmactrl = gr_read32(&ep->regs->dmactrl);
426	gr_write32(&ep->regs->dmactrl, dmactrl | GR_DMACTRL_AD);
427}
428
429/*
430 * Allocates and sets up a struct gr_dma_desc and putting it on the descriptor
431 * chain.
432 *
433 * Size is not used for OUT endpoints. Hardware can not be instructed to handle
434 * smaller buffer than MAXPL in the OUT direction.
435 */
436static int gr_add_dma_desc(struct gr_ep *ep, struct gr_request *req,
437			   dma_addr_t data, unsigned size, gfp_t gfp_flags)
438{
439	struct gr_dma_desc *desc;
440
441	desc = gr_alloc_dma_desc(ep, gfp_flags);
442	if (!desc)
443		return -ENOMEM;
444
445	desc->data = data;
446	if (ep->is_in)
447		desc->ctrl =
448			(GR_DESC_IN_CTRL_LEN_MASK & size) | GR_DESC_IN_CTRL_EN;
449	else
450		desc->ctrl = GR_DESC_OUT_CTRL_IE;
451
452	if (!req->first_desc) {
453		req->first_desc = desc;
454		req->curr_desc = desc;
455	} else {
456		req->last_desc->next_desc = desc;
457		req->last_desc->next = desc->paddr;
458		req->last_desc->ctrl |= GR_DESC_OUT_CTRL_NX;
459	}
460	req->last_desc = desc;
461
462	return 0;
463}
464
465/*
466 * Sets up a chain of struct gr_dma_descriptors pointing to buffers that
467 * together covers req->req.length bytes of the buffer at DMA address
468 * req->req.dma for the OUT direction.
469 *
470 * The first descriptor in the chain is enabled, the rest disabled. The
471 * interrupt handler will later enable them one by one when needed so we can
472 * find out when the transfer is finished. For OUT endpoints, all descriptors
473 * therefore generate interrutps.
474 */
475static int gr_setup_out_desc_list(struct gr_ep *ep, struct gr_request *req,
476				  gfp_t gfp_flags)
477{
478	u16 bytes_left; /* Bytes left to provide descriptors for */
479	u16 bytes_used; /* Bytes accommodated for */
480	int ret = 0;
481
482	req->first_desc = NULL; /* Signals that no allocation is done yet */
483	bytes_left = req->req.length;
484	bytes_used = 0;
485	while (bytes_left > 0) {
486		dma_addr_t start = req->req.dma + bytes_used;
487		u16 size = min(bytes_left, ep->bytes_per_buffer);
488
489		if (size < ep->bytes_per_buffer) {
490			/* Prepare using bounce buffer */
491			req->evenlen = req->req.length - bytes_left;
492			req->oddlen = size;
493		}
494
495		ret = gr_add_dma_desc(ep, req, start, size, gfp_flags);
496		if (ret)
497			goto alloc_err;
498
499		bytes_left -= size;
500		bytes_used += size;
501	}
502
503	req->first_desc->ctrl |= GR_DESC_OUT_CTRL_EN;
504
505	return 0;
506
507alloc_err:
508	gr_free_dma_desc_chain(ep->dev, req);
509
510	return ret;
511}
512
513/*
514 * Sets up a chain of struct gr_dma_descriptors pointing to buffers that
515 * together covers req->req.length bytes of the buffer at DMA address
516 * req->req.dma for the IN direction.
517 *
518 * When more data is provided than the maximum payload size, the hardware splits
519 * this up into several payloads automatically. Moreover, ep->bytes_per_buffer
520 * is always set to a multiple of the maximum payload (restricted to the valid
521 * number of maximum payloads during high bandwidth isochronous or interrupt
522 * transfers)
523 *
524 * All descriptors are enabled from the beginning and we only generate an
525 * interrupt for the last one indicating that the entire request has been pushed
526 * to hardware.
527 */
528static int gr_setup_in_desc_list(struct gr_ep *ep, struct gr_request *req,
529				 gfp_t gfp_flags)
530{
531	u16 bytes_left; /* Bytes left in req to provide descriptors for */
532	u16 bytes_used; /* Bytes in req accommodated for */
533	int ret = 0;
534
535	req->first_desc = NULL; /* Signals that no allocation is done yet */
536	bytes_left = req->req.length;
537	bytes_used = 0;
538	do { /* Allow for zero length packets */
539		dma_addr_t start = req->req.dma + bytes_used;
540		u16 size = min(bytes_left, ep->bytes_per_buffer);
541
542		ret = gr_add_dma_desc(ep, req, start, size, gfp_flags);
543		if (ret)
544			goto alloc_err;
545
546		bytes_left -= size;
547		bytes_used += size;
548	} while (bytes_left > 0);
549
550	/*
551	 * Send an extra zero length packet to indicate that no more data is
552	 * available when req->req.zero is set and the data length is even
553	 * multiples of ep->ep.maxpacket.
554	 */
555	if (req->req.zero && (req->req.length % ep->ep.maxpacket == 0)) {
556		ret = gr_add_dma_desc(ep, req, 0, 0, gfp_flags);
557		if (ret)
558			goto alloc_err;
559	}
560
561	/*
562	 * For IN packets we only want to know when the last packet has been
563	 * transmitted (not just put into internal buffers).
564	 */
565	req->last_desc->ctrl |= GR_DESC_IN_CTRL_PI;
566
567	return 0;
568
569alloc_err:
570	gr_free_dma_desc_chain(ep->dev, req);
571
572	return ret;
573}
574
575/* Must be called with dev->lock held */
576static int gr_queue(struct gr_ep *ep, struct gr_request *req, gfp_t gfp_flags)
577{
578	struct gr_udc *dev = ep->dev;
579	int ret;
580
581	if (unlikely(!ep->ep.desc && ep->num != 0)) {
582		dev_err(dev->dev, "No ep descriptor for %s\n", ep->ep.name);
583		return -EINVAL;
584	}
585
586	if (unlikely(!req->req.buf || !list_empty(&req->queue))) {
587		dev_err(dev->dev,
588			"Invalid request for %s: buf=%p list_empty=%d\n",
589			ep->ep.name, req->req.buf, list_empty(&req->queue));
590		return -EINVAL;
591	}
592
593	if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)) {
594		dev_err(dev->dev, "-ESHUTDOWN");
595		return -ESHUTDOWN;
596	}
597
598	/* Can't touch registers when suspended */
599	if (dev->ep0state == GR_EP0_SUSPEND) {
600		dev_err(dev->dev, "-EBUSY");
601		return -EBUSY;
602	}
603
604	/* Set up DMA mapping in case the caller didn't */
605	ret = usb_gadget_map_request(&dev->gadget, &req->req, ep->is_in);
606	if (ret) {
607		dev_err(dev->dev, "usb_gadget_map_request");
608		return ret;
609	}
610
611	if (ep->is_in)
612		ret = gr_setup_in_desc_list(ep, req, gfp_flags);
613	else
614		ret = gr_setup_out_desc_list(ep, req, gfp_flags);
615	if (ret)
616		return ret;
617
618	req->req.status = -EINPROGRESS;
619	req->req.actual = 0;
620	list_add_tail(&req->queue, &ep->queue);
621
622	/* Start DMA if not started, otherwise interrupt handler handles it */
623	if (!ep->dma_start && likely(!ep->stopped))
624		gr_start_dma(ep);
625
626	return 0;
627}
628
629/*
630 * Queue a request from within the driver.
631 *
632 * Must be called with dev->lock held.
633 */
634static inline int gr_queue_int(struct gr_ep *ep, struct gr_request *req,
635			       gfp_t gfp_flags)
636{
637	if (ep->is_in)
638		gr_dbgprint_request("RESP", ep, req);
639
640	return gr_queue(ep, req, gfp_flags);
641}
642
643/* ---------------------------------------------------------------------- */
644/* General helper functions */
645
646/*
647 * Dequeue ALL requests.
648 *
649 * Must be called with dev->lock held and irqs disabled.
650 */
651static void gr_ep_nuke(struct gr_ep *ep)
652{
653	struct gr_request *req;
654
655	ep->stopped = 1;
656	ep->dma_start = 0;
657	gr_abort_dma(ep);
658
659	while (!list_empty(&ep->queue)) {
660		req = list_first_entry(&ep->queue, struct gr_request, queue);
661		gr_finish_request(ep, req, -ESHUTDOWN);
662	}
663}
664
665/*
666 * Reset the hardware state of this endpoint.
667 *
668 * Must be called with dev->lock held.
669 */
670static void gr_ep_reset(struct gr_ep *ep)
671{
672	gr_write32(&ep->regs->epctrl, 0);
673	gr_write32(&ep->regs->dmactrl, 0);
674
675	ep->ep.maxpacket = MAX_CTRL_PL_SIZE;
676	ep->ep.desc = NULL;
677	ep->stopped = 1;
678	ep->dma_start = 0;
679}
680
681/*
682 * Generate STALL on ep0in/out.
683 *
684 * Must be called with dev->lock held.
685 */
686static void gr_control_stall(struct gr_udc *dev)
687{
688	u32 epctrl;
689
690	epctrl = gr_read32(&dev->epo[0].regs->epctrl);
691	gr_write32(&dev->epo[0].regs->epctrl, epctrl | GR_EPCTRL_CS);
692	epctrl = gr_read32(&dev->epi[0].regs->epctrl);
693	gr_write32(&dev->epi[0].regs->epctrl, epctrl | GR_EPCTRL_CS);
694
695	dev->ep0state = GR_EP0_STALL;
696}
697
698/*
699 * Halts, halts and wedges, or clears halt for an endpoint.
700 *
701 * Must be called with dev->lock held.
702 */
703static int gr_ep_halt_wedge(struct gr_ep *ep, int halt, int wedge, int fromhost)
704{
705	u32 epctrl;
706	int retval = 0;
707
708	if (ep->num && !ep->ep.desc)
709		return -EINVAL;
710
711	if (ep->num && ep->ep.desc->bmAttributes == USB_ENDPOINT_XFER_ISOC)
712		return -EOPNOTSUPP;
713
714	/* Never actually halt ep0, and therefore never clear halt for ep0 */
715	if (!ep->num) {
716		if (halt && !fromhost) {
717			/* ep0 halt from gadget - generate protocol stall */
718			gr_control_stall(ep->dev);
719			dev_dbg(ep->dev->dev, "EP: stall ep0\n");
720			return 0;
721		}
722		return -EINVAL;
723	}
724
725	dev_dbg(ep->dev->dev, "EP: %s halt %s\n",
726		(halt ? (wedge ? "wedge" : "set") : "clear"), ep->ep.name);
727
728	epctrl = gr_read32(&ep->regs->epctrl);
729	if (halt) {
730		/* Set HALT */
731		gr_write32(&ep->regs->epctrl, epctrl | GR_EPCTRL_EH);
732		ep->stopped = 1;
733		if (wedge)
734			ep->wedged = 1;
735	} else {
736		gr_write32(&ep->regs->epctrl, epctrl & ~GR_EPCTRL_EH);
737		ep->stopped = 0;
738		ep->wedged = 0;
739
740		/* Things might have been queued up in the meantime */
741		if (!ep->dma_start)
742			gr_start_dma(ep);
743	}
744
745	return retval;
746}
747
748/* Must be called with dev->lock held */
749static inline void gr_set_ep0state(struct gr_udc *dev, enum gr_ep0state value)
750{
751	if (dev->ep0state != value)
752		dev_vdbg(dev->dev, "STATE:  ep0state=%s\n",
753			 gr_ep0state_string(value));
754	dev->ep0state = value;
755}
756
757/*
758 * Should only be called when endpoints can not generate interrupts.
759 *
760 * Must be called with dev->lock held.
761 */
762static void gr_disable_interrupts_and_pullup(struct gr_udc *dev)
763{
764	gr_write32(&dev->regs->control, 0);
765	wmb(); /* Make sure that we do not deny one of our interrupts */
766	dev->irq_enabled = 0;
767}
768
769/*
770 * Stop all device activity and disable data line pullup.
771 *
772 * Must be called with dev->lock held and irqs disabled.
773 */
774static void gr_stop_activity(struct gr_udc *dev)
775{
776	struct gr_ep *ep;
777
778	list_for_each_entry(ep, &dev->ep_list, ep_list)
779		gr_ep_nuke(ep);
780
781	gr_disable_interrupts_and_pullup(dev);
782
783	gr_set_ep0state(dev, GR_EP0_DISCONNECT);
784	usb_gadget_set_state(&dev->gadget, USB_STATE_NOTATTACHED);
785}
786
787/* ---------------------------------------------------------------------- */
788/* ep0 setup packet handling */
789
790static void gr_ep0_testmode_complete(struct usb_ep *_ep,
791				     struct usb_request *_req)
792{
793	struct gr_ep *ep;
794	struct gr_udc *dev;
795	u32 control;
796
797	ep = container_of(_ep, struct gr_ep, ep);
798	dev = ep->dev;
799
800	spin_lock(&dev->lock);
801
802	control = gr_read32(&dev->regs->control);
803	control |= GR_CONTROL_TM | (dev->test_mode << GR_CONTROL_TS_POS);
804	gr_write32(&dev->regs->control, control);
805
806	spin_unlock(&dev->lock);
807}
808
809static void gr_ep0_dummy_complete(struct usb_ep *_ep, struct usb_request *_req)
810{
811	/* Nothing needs to be done here */
812}
813
814/*
815 * Queue a response on ep0in.
816 *
817 * Must be called with dev->lock held.
818 */
819static int gr_ep0_respond(struct gr_udc *dev, u8 *buf, int length,
820			  void (*complete)(struct usb_ep *ep,
821					   struct usb_request *req))
822{
823	u8 *reqbuf = dev->ep0reqi->req.buf;
824	int status;
825	int i;
826
827	for (i = 0; i < length; i++)
828		reqbuf[i] = buf[i];
829	dev->ep0reqi->req.length = length;
830	dev->ep0reqi->req.complete = complete;
831
832	status = gr_queue_int(&dev->epi[0], dev->ep0reqi, GFP_ATOMIC);
833	if (status < 0)
834		dev_err(dev->dev,
835			"Could not queue ep0in setup response: %d\n", status);
836
837	return status;
838}
839
840/*
841 * Queue a 2 byte response on ep0in.
842 *
843 * Must be called with dev->lock held.
844 */
845static inline int gr_ep0_respond_u16(struct gr_udc *dev, u16 response)
846{
847	__le16 le_response = cpu_to_le16(response);
848
849	return gr_ep0_respond(dev, (u8 *)&le_response, 2,
850			      gr_ep0_dummy_complete);
851}
852
853/*
854 * Queue a ZLP response on ep0in.
855 *
856 * Must be called with dev->lock held.
857 */
858static inline int gr_ep0_respond_empty(struct gr_udc *dev)
859{
860	return gr_ep0_respond(dev, NULL, 0, gr_ep0_dummy_complete);
861}
862
863/*
864 * This is run when a SET_ADDRESS request is received. First writes
865 * the new address to the control register which is updated internally
866 * when the next IN packet is ACKED.
867 *
868 * Must be called with dev->lock held.
869 */
870static void gr_set_address(struct gr_udc *dev, u8 address)
871{
872	u32 control;
873
874	control = gr_read32(&dev->regs->control) & ~GR_CONTROL_UA_MASK;
875	control |= (address << GR_CONTROL_UA_POS) & GR_CONTROL_UA_MASK;
876	control |= GR_CONTROL_SU;
877	gr_write32(&dev->regs->control, control);
878}
879
880/*
881 * Returns negative for STALL, 0 for successful handling and positive for
882 * delegation.
883 *
884 * Must be called with dev->lock held.
885 */
886static int gr_device_request(struct gr_udc *dev, u8 type, u8 request,
887			     u16 value, u16 index)
888{
889	u16 response;
890	u8 test;
891
892	switch (request) {
893	case USB_REQ_SET_ADDRESS:
894		dev_dbg(dev->dev, "STATUS: address %d\n", value & 0xff);
895		gr_set_address(dev, value & 0xff);
896		if (value)
897			usb_gadget_set_state(&dev->gadget, USB_STATE_ADDRESS);
898		else
899			usb_gadget_set_state(&dev->gadget, USB_STATE_DEFAULT);
900		return gr_ep0_respond_empty(dev);
901
902	case USB_REQ_GET_STATUS:
903		/* Self powered | remote wakeup */
904		response = 0x0001 | (dev->remote_wakeup ? 0x0002 : 0);
905		return gr_ep0_respond_u16(dev, response);
906
907	case USB_REQ_SET_FEATURE:
908		switch (value) {
909		case USB_DEVICE_REMOTE_WAKEUP:
910			/* Allow remote wakeup */
911			dev->remote_wakeup = 1;
912			return gr_ep0_respond_empty(dev);
913
914		case USB_DEVICE_TEST_MODE:
915			/* The hardware does not support USB_TEST_FORCE_ENABLE */
916			test = index >> 8;
917			if (test >= USB_TEST_J && test <= USB_TEST_PACKET) {
918				dev->test_mode = test;
919				return gr_ep0_respond(dev, NULL, 0,
920						      gr_ep0_testmode_complete);
921			}
922		}
923		break;
924
925	case USB_REQ_CLEAR_FEATURE:
926		switch (value) {
927		case USB_DEVICE_REMOTE_WAKEUP:
928			/* Disallow remote wakeup */
929			dev->remote_wakeup = 0;
930			return gr_ep0_respond_empty(dev);
931		}
932		break;
933	}
934
935	return 1; /* Delegate the rest */
936}
937
938/*
939 * Returns negative for STALL, 0 for successful handling and positive for
940 * delegation.
941 *
942 * Must be called with dev->lock held.
943 */
944static int gr_interface_request(struct gr_udc *dev, u8 type, u8 request,
945				u16 value, u16 index)
946{
947	if (dev->gadget.state != USB_STATE_CONFIGURED)
948		return -1;
949
950	/*
951	 * Should return STALL for invalid interfaces, but udc driver does not
952	 * know anything about that. However, many gadget drivers do not handle
953	 * GET_STATUS so we need to take care of that.
954	 */
955
956	switch (request) {
957	case USB_REQ_GET_STATUS:
958		return gr_ep0_respond_u16(dev, 0x0000);
959
960	case USB_REQ_SET_FEATURE:
961	case USB_REQ_CLEAR_FEATURE:
962		/*
963		 * No possible valid standard requests. Still let gadget drivers
964		 * have a go at it.
965		 */
966		break;
967	}
968
969	return 1; /* Delegate the rest */
970}
971
972/*
973 * Returns negative for STALL, 0 for successful handling and positive for
974 * delegation.
975 *
976 * Must be called with dev->lock held.
977 */
978static int gr_endpoint_request(struct gr_udc *dev, u8 type, u8 request,
979			       u16 value, u16 index)
980{
981	struct gr_ep *ep;
982	int status;
983	int halted;
984	u8 epnum = index & USB_ENDPOINT_NUMBER_MASK;
985	u8 is_in = index & USB_ENDPOINT_DIR_MASK;
986
987	if ((is_in && epnum >= dev->nepi) || (!is_in && epnum >= dev->nepo))
988		return -1;
989
990	if (dev->gadget.state != USB_STATE_CONFIGURED && epnum != 0)
991		return -1;
992
993	ep = (is_in ? &dev->epi[epnum] : &dev->epo[epnum]);
994
995	switch (request) {
996	case USB_REQ_GET_STATUS:
997		halted = gr_read32(&ep->regs->epctrl) & GR_EPCTRL_EH;
998		return gr_ep0_respond_u16(dev, halted ? 0x0001 : 0);
999
1000	case USB_REQ_SET_FEATURE:
1001		switch (value) {
1002		case USB_ENDPOINT_HALT:
1003			status = gr_ep_halt_wedge(ep, 1, 0, 1);
1004			if (status >= 0)
1005				status = gr_ep0_respond_empty(dev);
1006			return status;
1007		}
1008		break;
1009
1010	case USB_REQ_CLEAR_FEATURE:
1011		switch (value) {
1012		case USB_ENDPOINT_HALT:
1013			if (ep->wedged)
1014				return -1;
1015			status = gr_ep_halt_wedge(ep, 0, 0, 1);
1016			if (status >= 0)
1017				status = gr_ep0_respond_empty(dev);
1018			return status;
1019		}
1020		break;
1021	}
1022
1023	return 1; /* Delegate the rest */
1024}
1025
1026/* Must be called with dev->lock held */
1027static void gr_ep0out_requeue(struct gr_udc *dev)
1028{
1029	int ret = gr_queue_int(&dev->epo[0], dev->ep0reqo, GFP_ATOMIC);
1030
1031	if (ret)
1032		dev_err(dev->dev, "Could not queue ep0out setup request: %d\n",
1033			ret);
1034}
1035
1036/*
1037 * The main function dealing with setup requests on ep0.
1038 *
1039 * Must be called with dev->lock held and irqs disabled
1040 */
1041static void gr_ep0_setup(struct gr_udc *dev, struct gr_request *req)
1042	__releases(&dev->lock)
1043	__acquires(&dev->lock)
1044{
1045	union {
1046		struct usb_ctrlrequest ctrl;
1047		u8 raw[8];
1048		u32 word[2];
1049	} u;
1050	u8 type;
1051	u8 request;
1052	u16 value;
1053	u16 index;
1054	u16 length;
1055	int i;
1056	int status;
1057
1058	/* Restore from ep0 halt */
1059	if (dev->ep0state == GR_EP0_STALL) {
1060		gr_set_ep0state(dev, GR_EP0_SETUP);
1061		if (!req->req.actual)
1062			goto out;
1063	}
1064
1065	if (dev->ep0state == GR_EP0_ISTATUS) {
1066		gr_set_ep0state(dev, GR_EP0_SETUP);
1067		if (req->req.actual > 0)
1068			dev_dbg(dev->dev,
1069				"Unexpected setup packet at state %s\n",
1070				gr_ep0state_string(GR_EP0_ISTATUS));
1071		else
1072			goto out; /* Got expected ZLP */
1073	} else if (dev->ep0state != GR_EP0_SETUP) {
1074		dev_info(dev->dev,
1075			 "Unexpected ep0out request at state %s - stalling\n",
1076			 gr_ep0state_string(dev->ep0state));
1077		gr_control_stall(dev);
1078		gr_set_ep0state(dev, GR_EP0_SETUP);
1079		goto out;
1080	} else if (!req->req.actual) {
1081		dev_dbg(dev->dev, "Unexpected ZLP at state %s\n",
1082			gr_ep0state_string(dev->ep0state));
1083		goto out;
1084	}
1085
1086	/* Handle SETUP packet */
1087	for (i = 0; i < req->req.actual; i++)
1088		u.raw[i] = ((u8 *)req->req.buf)[i];
1089
1090	type = u.ctrl.bRequestType;
1091	request = u.ctrl.bRequest;
1092	value = le16_to_cpu(u.ctrl.wValue);
1093	index = le16_to_cpu(u.ctrl.wIndex);
1094	length = le16_to_cpu(u.ctrl.wLength);
1095
1096	gr_dbgprint_devreq(dev, type, request, value, index, length);
1097
1098	/* Check for data stage */
1099	if (length) {
1100		if (type & USB_DIR_IN)
1101			gr_set_ep0state(dev, GR_EP0_IDATA);
1102		else
1103			gr_set_ep0state(dev, GR_EP0_ODATA);
1104	}
1105
1106	status = 1; /* Positive status flags delegation */
1107	if ((type & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
1108		switch (type & USB_RECIP_MASK) {
1109		case USB_RECIP_DEVICE:
1110			status = gr_device_request(dev, type, request,
1111						   value, index);
1112			break;
1113		case USB_RECIP_ENDPOINT:
1114			status =  gr_endpoint_request(dev, type, request,
1115						      value, index);
1116			break;
1117		case USB_RECIP_INTERFACE:
1118			status = gr_interface_request(dev, type, request,
1119						      value, index);
1120			break;
1121		}
1122	}
1123
1124	if (status > 0) {
1125		spin_unlock(&dev->lock);
1126
1127		dev_vdbg(dev->dev, "DELEGATE\n");
1128		status = dev->driver->setup(&dev->gadget, &u.ctrl);
1129
1130		spin_lock(&dev->lock);
1131	}
1132
1133	/* Generate STALL on both ep0out and ep0in if requested */
1134	if (unlikely(status < 0)) {
1135		dev_vdbg(dev->dev, "STALL\n");
1136		gr_control_stall(dev);
1137	}
1138
1139	if ((type & USB_TYPE_MASK) == USB_TYPE_STANDARD &&
1140	    request == USB_REQ_SET_CONFIGURATION) {
1141		if (!value) {
1142			dev_dbg(dev->dev, "STATUS: deconfigured\n");
1143			usb_gadget_set_state(&dev->gadget, USB_STATE_ADDRESS);
1144		} else if (status >= 0) {
1145			/* Not configured unless gadget OK:s it */
1146			dev_dbg(dev->dev, "STATUS: configured: %d\n", value);
1147			usb_gadget_set_state(&dev->gadget,
1148					     USB_STATE_CONFIGURED);
1149		}
1150	}
1151
1152	/* Get ready for next stage */
1153	if (dev->ep0state == GR_EP0_ODATA)
1154		gr_set_ep0state(dev, GR_EP0_OSTATUS);
1155	else if (dev->ep0state == GR_EP0_IDATA)
1156		gr_set_ep0state(dev, GR_EP0_ISTATUS);
1157	else
1158		gr_set_ep0state(dev, GR_EP0_SETUP);
1159
1160out:
1161	gr_ep0out_requeue(dev);
1162}
1163
1164/* ---------------------------------------------------------------------- */
1165/* VBUS and USB reset handling */
1166
1167/* Must be called with dev->lock held and irqs disabled  */
1168static void gr_vbus_connected(struct gr_udc *dev, u32 status)
1169{
1170	u32 control;
1171
1172	dev->gadget.speed = GR_SPEED(status);
1173	usb_gadget_set_state(&dev->gadget, USB_STATE_POWERED);
1174
1175	/* Turn on full interrupts and pullup */
1176	control = (GR_CONTROL_SI | GR_CONTROL_UI | GR_CONTROL_VI |
1177		   GR_CONTROL_SP | GR_CONTROL_EP);
1178	gr_write32(&dev->regs->control, control);
1179}
1180
1181/* Must be called with dev->lock held */
1182static void gr_enable_vbus_detect(struct gr_udc *dev)
1183{
1184	u32 status;
1185
1186	dev->irq_enabled = 1;
1187	wmb(); /* Make sure we do not ignore an interrupt */
1188	gr_write32(&dev->regs->control, GR_CONTROL_VI);
1189
1190	/* Take care of the case we are already plugged in at this point */
1191	status = gr_read32(&dev->regs->status);
1192	if (status & GR_STATUS_VB)
1193		gr_vbus_connected(dev, status);
1194}
1195
1196/* Must be called with dev->lock held and irqs disabled */
1197static void gr_vbus_disconnected(struct gr_udc *dev)
1198{
1199	gr_stop_activity(dev);
1200
1201	/* Report disconnect */
1202	if (dev->driver && dev->driver->disconnect) {
1203		spin_unlock(&dev->lock);
1204
1205		dev->driver->disconnect(&dev->gadget);
1206
1207		spin_lock(&dev->lock);
1208	}
1209
1210	gr_enable_vbus_detect(dev);
1211}
1212
1213/* Must be called with dev->lock held and irqs disabled */
1214static void gr_udc_usbreset(struct gr_udc *dev, u32 status)
1215{
1216	gr_set_address(dev, 0);
1217	gr_set_ep0state(dev, GR_EP0_SETUP);
1218	usb_gadget_set_state(&dev->gadget, USB_STATE_DEFAULT);
1219	dev->gadget.speed = GR_SPEED(status);
1220
1221	gr_ep_nuke(&dev->epo[0]);
1222	gr_ep_nuke(&dev->epi[0]);
1223	dev->epo[0].stopped = 0;
1224	dev->epi[0].stopped = 0;
1225	gr_ep0out_requeue(dev);
1226}
1227
1228/* ---------------------------------------------------------------------- */
1229/* Irq handling */
1230
1231/*
1232 * Handles interrupts from in endpoints. Returns whether something was handled.
1233 *
1234 * Must be called with dev->lock held, irqs disabled and with !ep->stopped.
1235 */
1236static int gr_handle_in_ep(struct gr_ep *ep)
1237{
1238	struct gr_request *req;
1239
1240	req = list_first_entry(&ep->queue, struct gr_request, queue);
1241	if (!req->last_desc)
1242		return 0;
1243
1244	if (READ_ONCE(req->last_desc->ctrl) & GR_DESC_IN_CTRL_EN)
1245		return 0; /* Not put in hardware buffers yet */
1246
1247	if (gr_read32(&ep->regs->epstat) & (GR_EPSTAT_B1 | GR_EPSTAT_B0))
1248		return 0; /* Not transmitted yet, still in hardware buffers */
1249
1250	/* Write complete */
1251	gr_dma_advance(ep, 0);
1252
1253	return 1;
1254}
1255
1256/*
1257 * Handles interrupts from out endpoints. Returns whether something was handled.
1258 *
1259 * Must be called with dev->lock held, irqs disabled and with !ep->stopped.
1260 */
1261static int gr_handle_out_ep(struct gr_ep *ep)
1262{
1263	u32 ep_dmactrl;
1264	u32 ctrl;
1265	u16 len;
1266	struct gr_request *req;
1267	struct gr_udc *dev = ep->dev;
1268
1269	req = list_first_entry(&ep->queue, struct gr_request, queue);
1270	if (!req->curr_desc)
1271		return 0;
1272
1273	ctrl = READ_ONCE(req->curr_desc->ctrl);
1274	if (ctrl & GR_DESC_OUT_CTRL_EN)
1275		return 0; /* Not received yet */
1276
1277	/* Read complete */
1278	len = ctrl & GR_DESC_OUT_CTRL_LEN_MASK;
1279	req->req.actual += len;
1280	if (ctrl & GR_DESC_OUT_CTRL_SE)
1281		req->setup = 1;
1282
1283	if (len < ep->ep.maxpacket || req->req.actual >= req->req.length) {
1284		/* Short packet or >= expected size - we are done */
1285
1286		if ((ep == &dev->epo[0]) && (dev->ep0state == GR_EP0_OSTATUS)) {
1287			/*
1288			 * Send a status stage ZLP to ack the DATA stage in the
1289			 * OUT direction. This needs to be done before
1290			 * gr_dma_advance as that can lead to a call to
1291			 * ep0_setup that can change dev->ep0state.
1292			 */
1293			gr_ep0_respond_empty(dev);
1294			gr_set_ep0state(dev, GR_EP0_SETUP);
1295		}
1296
1297		gr_dma_advance(ep, 0);
1298	} else {
1299		/* Not done yet. Enable the next descriptor to receive more. */
1300		req->curr_desc = req->curr_desc->next_desc;
1301		req->curr_desc->ctrl |= GR_DESC_OUT_CTRL_EN;
1302
1303		ep_dmactrl = gr_read32(&ep->regs->dmactrl);
1304		gr_write32(&ep->regs->dmactrl, ep_dmactrl | GR_DMACTRL_DA);
1305	}
1306
1307	return 1;
1308}
1309
1310/*
1311 * Handle state changes. Returns whether something was handled.
1312 *
1313 * Must be called with dev->lock held and irqs disabled.
1314 */
1315static int gr_handle_state_changes(struct gr_udc *dev)
1316{
1317	u32 status = gr_read32(&dev->regs->status);
1318	int handled = 0;
1319	int powstate = !(dev->gadget.state == USB_STATE_NOTATTACHED ||
1320			 dev->gadget.state == USB_STATE_ATTACHED);
1321
1322	/* VBUS valid detected */
1323	if (!powstate && (status & GR_STATUS_VB)) {
1324		dev_dbg(dev->dev, "STATUS: vbus valid detected\n");
1325		gr_vbus_connected(dev, status);
1326		handled = 1;
1327	}
1328
1329	/* Disconnect */
1330	if (powstate && !(status & GR_STATUS_VB)) {
1331		dev_dbg(dev->dev, "STATUS: vbus invalid detected\n");
1332		gr_vbus_disconnected(dev);
1333		handled = 1;
1334	}
1335
1336	/* USB reset detected */
1337	if (status & GR_STATUS_UR) {
1338		dev_dbg(dev->dev, "STATUS: USB reset - speed is %s\n",
1339			GR_SPEED_STR(status));
1340		gr_write32(&dev->regs->status, GR_STATUS_UR);
1341		gr_udc_usbreset(dev, status);
1342		handled = 1;
1343	}
1344
1345	/* Speed change */
1346	if (dev->gadget.speed != GR_SPEED(status)) {
1347		dev_dbg(dev->dev, "STATUS: USB Speed change to %s\n",
1348			GR_SPEED_STR(status));
1349		dev->gadget.speed = GR_SPEED(status);
1350		handled = 1;
1351	}
1352
1353	/* Going into suspend */
1354	if ((dev->ep0state != GR_EP0_SUSPEND) && !(status & GR_STATUS_SU)) {
1355		dev_dbg(dev->dev, "STATUS: USB suspend\n");
1356		gr_set_ep0state(dev, GR_EP0_SUSPEND);
1357		dev->suspended_from = dev->gadget.state;
1358		usb_gadget_set_state(&dev->gadget, USB_STATE_SUSPENDED);
1359
1360		if ((dev->gadget.speed != USB_SPEED_UNKNOWN) &&
1361		    dev->driver && dev->driver->suspend) {
1362			spin_unlock(&dev->lock);
1363
1364			dev->driver->suspend(&dev->gadget);
1365
1366			spin_lock(&dev->lock);
1367		}
1368		handled = 1;
1369	}
1370
1371	/* Coming out of suspend */
1372	if ((dev->ep0state == GR_EP0_SUSPEND) && (status & GR_STATUS_SU)) {
1373		dev_dbg(dev->dev, "STATUS: USB resume\n");
1374		if (dev->suspended_from == USB_STATE_POWERED)
1375			gr_set_ep0state(dev, GR_EP0_DISCONNECT);
1376		else
1377			gr_set_ep0state(dev, GR_EP0_SETUP);
1378		usb_gadget_set_state(&dev->gadget, dev->suspended_from);
1379
1380		if ((dev->gadget.speed != USB_SPEED_UNKNOWN) &&
1381		    dev->driver && dev->driver->resume) {
1382			spin_unlock(&dev->lock);
1383
1384			dev->driver->resume(&dev->gadget);
1385
1386			spin_lock(&dev->lock);
1387		}
1388		handled = 1;
1389	}
1390
1391	return handled;
1392}
1393
1394/* Non-interrupt context irq handler */
1395static irqreturn_t gr_irq_handler(int irq, void *_dev)
1396{
1397	struct gr_udc *dev = _dev;
1398	struct gr_ep *ep;
1399	int handled = 0;
1400	int i;
1401	unsigned long flags;
1402
1403	spin_lock_irqsave(&dev->lock, flags);
1404
1405	if (!dev->irq_enabled)
1406		goto out;
1407
1408	/*
1409	 * Check IN ep interrupts. We check these before the OUT eps because
1410	 * some gadgets reuse the request that might already be currently
1411	 * outstanding and needs to be completed (mainly setup requests).
1412	 */
1413	for (i = 0; i < dev->nepi; i++) {
1414		ep = &dev->epi[i];
1415		if (!ep->stopped && !ep->callback && !list_empty(&ep->queue))
1416			handled = gr_handle_in_ep(ep) || handled;
1417	}
1418
1419	/* Check OUT ep interrupts */
1420	for (i = 0; i < dev->nepo; i++) {
1421		ep = &dev->epo[i];
1422		if (!ep->stopped && !ep->callback && !list_empty(&ep->queue))
1423			handled = gr_handle_out_ep(ep) || handled;
1424	}
1425
1426	/* Check status interrupts */
1427	handled = gr_handle_state_changes(dev) || handled;
1428
1429	/*
1430	 * Check AMBA DMA errors. Only check if we didn't find anything else to
1431	 * handle because this shouldn't happen if we did everything right.
1432	 */
1433	if (!handled) {
1434		list_for_each_entry(ep, &dev->ep_list, ep_list) {
1435			if (gr_read32(&ep->regs->dmactrl) & GR_DMACTRL_AE) {
1436				dev_err(dev->dev,
1437					"AMBA Error occurred for %s\n",
1438					ep->ep.name);
1439				handled = 1;
1440			}
1441		}
1442	}
1443
1444out:
1445	spin_unlock_irqrestore(&dev->lock, flags);
1446
1447	return handled ? IRQ_HANDLED : IRQ_NONE;
1448}
1449
1450/* Interrupt context irq handler */
1451static irqreturn_t gr_irq(int irq, void *_dev)
1452{
1453	struct gr_udc *dev = _dev;
1454
1455	if (!dev->irq_enabled)
1456		return IRQ_NONE;
1457
1458	return IRQ_WAKE_THREAD;
1459}
1460
1461/* ---------------------------------------------------------------------- */
1462/* USB ep ops */
1463
1464/* Enable endpoint. Not for ep0in and ep0out that are handled separately. */
1465static int gr_ep_enable(struct usb_ep *_ep,
1466			const struct usb_endpoint_descriptor *desc)
1467{
1468	struct gr_udc *dev;
1469	struct gr_ep *ep;
1470	u8 mode;
1471	u8 nt;
1472	u16 max;
1473	u16 buffer_size = 0;
1474	u32 epctrl;
1475
1476	ep = container_of(_ep, struct gr_ep, ep);
1477	if (!_ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT)
1478		return -EINVAL;
1479
1480	dev = ep->dev;
1481
1482	/* 'ep0' IN and OUT are reserved */
1483	if (ep == &dev->epo[0] || ep == &dev->epi[0])
1484		return -EINVAL;
1485
1486	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)
1487		return -ESHUTDOWN;
1488
1489	/* Make sure we are clear for enabling */
1490	epctrl = gr_read32(&ep->regs->epctrl);
1491	if (epctrl & GR_EPCTRL_EV)
1492		return -EBUSY;
1493
1494	/* Check that directions match */
1495	if (!ep->is_in != !usb_endpoint_dir_in(desc))
1496		return -EINVAL;
1497
1498	/* Check ep num */
1499	if ((!ep->is_in && ep->num >= dev->nepo) ||
1500	    (ep->is_in && ep->num >= dev->nepi))
1501		return -EINVAL;
1502
1503	if (usb_endpoint_xfer_control(desc)) {
1504		mode = 0;
1505	} else if (usb_endpoint_xfer_isoc(desc)) {
1506		mode = 1;
1507	} else if (usb_endpoint_xfer_bulk(desc)) {
1508		mode = 2;
1509	} else if (usb_endpoint_xfer_int(desc)) {
1510		mode = 3;
1511	} else {
1512		dev_err(dev->dev, "Unknown transfer type for %s\n",
1513			ep->ep.name);
1514		return -EINVAL;
1515	}
1516
1517	/*
1518	 * Bits 10-0 set the max payload. 12-11 set the number of
1519	 * additional transactions.
1520	 */
1521	max = usb_endpoint_maxp(desc);
1522	nt = usb_endpoint_maxp_mult(desc) - 1;
1523	buffer_size = GR_BUFFER_SIZE(epctrl);
1524	if (nt && (mode == 0 || mode == 2)) {
1525		dev_err(dev->dev,
1526			"%s mode: multiple trans./microframe not valid\n",
1527			(mode == 2 ? "Bulk" : "Control"));
1528		return -EINVAL;
1529	} else if (nt == 0x3) {
1530		dev_err(dev->dev,
1531			"Invalid value 0x3 for additional trans./microframe\n");
1532		return -EINVAL;
1533	} else if ((nt + 1) * max > buffer_size) {
1534		dev_err(dev->dev, "Hw buffer size %d < max payload %d * %d\n",
1535			buffer_size, (nt + 1), max);
1536		return -EINVAL;
1537	} else if (max == 0) {
1538		dev_err(dev->dev, "Max payload cannot be set to 0\n");
1539		return -EINVAL;
1540	} else if (max > ep->ep.maxpacket_limit) {
1541		dev_err(dev->dev, "Requested max payload %d > limit %d\n",
1542			max, ep->ep.maxpacket_limit);
1543		return -EINVAL;
1544	}
1545
1546	spin_lock(&ep->dev->lock);
1547
1548	if (!ep->stopped) {
1549		spin_unlock(&ep->dev->lock);
1550		return -EBUSY;
1551	}
1552
1553	ep->stopped = 0;
1554	ep->wedged = 0;
1555	ep->ep.desc = desc;
1556	ep->ep.maxpacket = max;
1557	ep->dma_start = 0;
1558
1559
1560	if (nt) {
1561		/*
1562		 * Maximum possible size of all payloads in one microframe
1563		 * regardless of direction when using high-bandwidth mode.
1564		 */
1565		ep->bytes_per_buffer = (nt + 1) * max;
1566	} else if (ep->is_in) {
1567		/*
1568		 * The biggest multiple of maximum packet size that fits into
1569		 * the buffer. The hardware will split up into many packets in
1570		 * the IN direction.
1571		 */
1572		ep->bytes_per_buffer = (buffer_size / max) * max;
1573	} else {
1574		/*
1575		 * Only single packets will be placed the buffers in the OUT
1576		 * direction.
1577		 */
1578		ep->bytes_per_buffer = max;
1579	}
1580
1581	epctrl = (max << GR_EPCTRL_MAXPL_POS)
1582		| (nt << GR_EPCTRL_NT_POS)
1583		| (mode << GR_EPCTRL_TT_POS)
1584		| GR_EPCTRL_EV;
1585	if (ep->is_in)
1586		epctrl |= GR_EPCTRL_PI;
1587	gr_write32(&ep->regs->epctrl, epctrl);
1588
1589	gr_write32(&ep->regs->dmactrl, GR_DMACTRL_IE | GR_DMACTRL_AI);
1590
1591	spin_unlock(&ep->dev->lock);
1592
1593	dev_dbg(ep->dev->dev, "EP: %s enabled - %s with %d bytes/buffer\n",
1594		ep->ep.name, gr_modestring[mode], ep->bytes_per_buffer);
1595	return 0;
1596}
1597
1598/* Disable endpoint. Not for ep0in and ep0out that are handled separately. */
1599static int gr_ep_disable(struct usb_ep *_ep)
1600{
1601	struct gr_ep *ep;
1602	struct gr_udc *dev;
1603	unsigned long flags;
1604
1605	ep = container_of(_ep, struct gr_ep, ep);
1606	if (!_ep || !ep->ep.desc)
1607		return -ENODEV;
1608
1609	dev = ep->dev;
1610
1611	/* 'ep0' IN and OUT are reserved */
1612	if (ep == &dev->epo[0] || ep == &dev->epi[0])
1613		return -EINVAL;
1614
1615	if (dev->ep0state == GR_EP0_SUSPEND)
1616		return -EBUSY;
1617
1618	dev_dbg(ep->dev->dev, "EP: disable %s\n", ep->ep.name);
1619
1620	spin_lock_irqsave(&dev->lock, flags);
1621
1622	gr_ep_nuke(ep);
1623	gr_ep_reset(ep);
1624	ep->ep.desc = NULL;
1625
1626	spin_unlock_irqrestore(&dev->lock, flags);
1627
1628	return 0;
1629}
1630
1631/*
1632 * Frees a request, but not any DMA buffers associated with it
1633 * (gr_finish_request should already have taken care of that).
1634 */
1635static void gr_free_request(struct usb_ep *_ep, struct usb_request *_req)
1636{
1637	struct gr_request *req;
1638
1639	if (!_ep || !_req)
1640		return;
1641	req = container_of(_req, struct gr_request, req);
1642
1643	/* Leads to memory leak */
1644	WARN(!list_empty(&req->queue),
1645	     "request not dequeued properly before freeing\n");
1646
1647	kfree(req);
1648}
1649
1650/* Queue a request from the gadget */
1651static int gr_queue_ext(struct usb_ep *_ep, struct usb_request *_req,
1652			gfp_t gfp_flags)
1653{
1654	struct gr_ep *ep;
1655	struct gr_request *req;
1656	struct gr_udc *dev;
1657	int ret;
1658
1659	if (unlikely(!_ep || !_req))
1660		return -EINVAL;
1661
1662	ep = container_of(_ep, struct gr_ep, ep);
1663	req = container_of(_req, struct gr_request, req);
1664	dev = ep->dev;
1665
1666	spin_lock(&ep->dev->lock);
1667
1668	/*
1669	 * The ep0 pointer in the gadget struct is used both for ep0in and
1670	 * ep0out. In a data stage in the out direction ep0out needs to be used
1671	 * instead of the default ep0in. Completion functions might use
1672	 * driver_data, so that needs to be copied as well.
1673	 */
1674	if ((ep == &dev->epi[0]) && (dev->ep0state == GR_EP0_ODATA)) {
1675		ep = &dev->epo[0];
1676		ep->ep.driver_data = dev->epi[0].ep.driver_data;
1677	}
1678
1679	if (ep->is_in)
1680		gr_dbgprint_request("EXTERN", ep, req);
1681
1682	ret = gr_queue(ep, req, GFP_ATOMIC);
1683
1684	spin_unlock(&ep->dev->lock);
1685
1686	return ret;
1687}
1688
1689/* Dequeue JUST ONE request */
1690static int gr_dequeue(struct usb_ep *_ep, struct usb_request *_req)
1691{
1692	struct gr_request *req = NULL, *iter;
1693	struct gr_ep *ep;
1694	struct gr_udc *dev;
1695	int ret = 0;
1696	unsigned long flags;
1697
1698	ep = container_of(_ep, struct gr_ep, ep);
1699	if (!_ep || !_req || (!ep->ep.desc && ep->num != 0))
1700		return -EINVAL;
1701	dev = ep->dev;
1702	if (!dev->driver)
1703		return -ESHUTDOWN;
1704
1705	/* We can't touch (DMA) registers when suspended */
1706	if (dev->ep0state == GR_EP0_SUSPEND)
1707		return -EBUSY;
1708
1709	spin_lock_irqsave(&dev->lock, flags);
1710
1711	/* Make sure it's actually queued on this endpoint */
1712	list_for_each_entry(iter, &ep->queue, queue) {
1713		if (&iter->req != _req)
1714			continue;
1715		req = iter;
1716		break;
1717	}
1718	if (!req) {
1719		ret = -EINVAL;
1720		goto out;
1721	}
1722
1723	if (list_first_entry(&ep->queue, struct gr_request, queue) == req) {
1724		/* This request is currently being processed */
1725		gr_abort_dma(ep);
1726		if (ep->stopped)
1727			gr_finish_request(ep, req, -ECONNRESET);
1728		else
1729			gr_dma_advance(ep, -ECONNRESET);
1730	} else if (!list_empty(&req->queue)) {
1731		/* Not being processed - gr_finish_request dequeues it */
1732		gr_finish_request(ep, req, -ECONNRESET);
1733	} else {
1734		ret = -EOPNOTSUPP;
1735	}
1736
1737out:
1738	spin_unlock_irqrestore(&dev->lock, flags);
1739
1740	return ret;
1741}
1742
1743/* Helper for gr_set_halt and gr_set_wedge */
1744static int gr_set_halt_wedge(struct usb_ep *_ep, int halt, int wedge)
1745{
1746	int ret;
1747	struct gr_ep *ep;
1748
1749	if (!_ep)
1750		return -ENODEV;
1751	ep = container_of(_ep, struct gr_ep, ep);
1752
1753	spin_lock(&ep->dev->lock);
1754
1755	/* Halting an IN endpoint should fail if queue is not empty */
1756	if (halt && ep->is_in && !list_empty(&ep->queue)) {
1757		ret = -EAGAIN;
1758		goto out;
1759	}
1760
1761	ret = gr_ep_halt_wedge(ep, halt, wedge, 0);
1762
1763out:
1764	spin_unlock(&ep->dev->lock);
1765
1766	return ret;
1767}
1768
1769/* Halt endpoint */
1770static int gr_set_halt(struct usb_ep *_ep, int halt)
1771{
1772	return gr_set_halt_wedge(_ep, halt, 0);
1773}
1774
1775/* Halt and wedge endpoint */
1776static int gr_set_wedge(struct usb_ep *_ep)
1777{
1778	return gr_set_halt_wedge(_ep, 1, 1);
1779}
1780
1781/*
1782 * Return the total number of bytes currently stored in the internal buffers of
1783 * the endpoint.
1784 */
1785static int gr_fifo_status(struct usb_ep *_ep)
1786{
1787	struct gr_ep *ep;
1788	u32 epstat;
1789	u32 bytes = 0;
1790
1791	if (!_ep)
1792		return -ENODEV;
1793	ep = container_of(_ep, struct gr_ep, ep);
1794
1795	epstat = gr_read32(&ep->regs->epstat);
1796
1797	if (epstat & GR_EPSTAT_B0)
1798		bytes += (epstat & GR_EPSTAT_B0CNT_MASK) >> GR_EPSTAT_B0CNT_POS;
1799	if (epstat & GR_EPSTAT_B1)
1800		bytes += (epstat & GR_EPSTAT_B1CNT_MASK) >> GR_EPSTAT_B1CNT_POS;
1801
1802	return bytes;
1803}
1804
1805
1806/* Empty data from internal buffers of an endpoint. */
1807static void gr_fifo_flush(struct usb_ep *_ep)
1808{
1809	struct gr_ep *ep;
1810	u32 epctrl;
1811
1812	if (!_ep)
1813		return;
1814	ep = container_of(_ep, struct gr_ep, ep);
1815	dev_vdbg(ep->dev->dev, "EP: flush fifo %s\n", ep->ep.name);
1816
1817	spin_lock(&ep->dev->lock);
1818
1819	epctrl = gr_read32(&ep->regs->epctrl);
1820	epctrl |= GR_EPCTRL_CB;
1821	gr_write32(&ep->regs->epctrl, epctrl);
1822
1823	spin_unlock(&ep->dev->lock);
1824}
1825
1826static const struct usb_ep_ops gr_ep_ops = {
1827	.enable		= gr_ep_enable,
1828	.disable	= gr_ep_disable,
1829
1830	.alloc_request	= gr_alloc_request,
1831	.free_request	= gr_free_request,
1832
1833	.queue		= gr_queue_ext,
1834	.dequeue	= gr_dequeue,
1835
1836	.set_halt	= gr_set_halt,
1837	.set_wedge	= gr_set_wedge,
1838	.fifo_status	= gr_fifo_status,
1839	.fifo_flush	= gr_fifo_flush,
1840};
1841
1842/* ---------------------------------------------------------------------- */
1843/* USB Gadget ops */
1844
1845static int gr_get_frame(struct usb_gadget *_gadget)
1846{
1847	struct gr_udc *dev;
1848
1849	if (!_gadget)
1850		return -ENODEV;
1851	dev = container_of(_gadget, struct gr_udc, gadget);
1852	return gr_read32(&dev->regs->status) & GR_STATUS_FN_MASK;
1853}
1854
1855static int gr_wakeup(struct usb_gadget *_gadget)
1856{
1857	struct gr_udc *dev;
1858
1859	if (!_gadget)
1860		return -ENODEV;
1861	dev = container_of(_gadget, struct gr_udc, gadget);
1862
1863	/* Remote wakeup feature not enabled by host*/
1864	if (!dev->remote_wakeup)
1865		return -EINVAL;
1866
1867	spin_lock(&dev->lock);
1868
1869	gr_write32(&dev->regs->control,
1870		   gr_read32(&dev->regs->control) | GR_CONTROL_RW);
1871
1872	spin_unlock(&dev->lock);
1873
1874	return 0;
1875}
1876
1877static int gr_pullup(struct usb_gadget *_gadget, int is_on)
1878{
1879	struct gr_udc *dev;
1880	u32 control;
1881
1882	if (!_gadget)
1883		return -ENODEV;
1884	dev = container_of(_gadget, struct gr_udc, gadget);
1885
1886	spin_lock(&dev->lock);
1887
1888	control = gr_read32(&dev->regs->control);
1889	if (is_on)
1890		control |= GR_CONTROL_EP;
1891	else
1892		control &= ~GR_CONTROL_EP;
1893	gr_write32(&dev->regs->control, control);
1894
1895	spin_unlock(&dev->lock);
1896
1897	return 0;
1898}
1899
1900static int gr_udc_start(struct usb_gadget *gadget,
1901			struct usb_gadget_driver *driver)
1902{
1903	struct gr_udc *dev = to_gr_udc(gadget);
1904
1905	spin_lock(&dev->lock);
1906
1907	/* Hook up the driver */
1908	dev->driver = driver;
1909
1910	/* Get ready for host detection */
1911	gr_enable_vbus_detect(dev);
1912
1913	spin_unlock(&dev->lock);
1914
1915	return 0;
1916}
1917
1918static int gr_udc_stop(struct usb_gadget *gadget)
1919{
1920	struct gr_udc *dev = to_gr_udc(gadget);
1921	unsigned long flags;
1922
1923	spin_lock_irqsave(&dev->lock, flags);
1924
1925	dev->driver = NULL;
1926	gr_stop_activity(dev);
1927
1928	spin_unlock_irqrestore(&dev->lock, flags);
1929
1930	return 0;
1931}
1932
1933static const struct usb_gadget_ops gr_ops = {
1934	.get_frame	= gr_get_frame,
1935	.wakeup         = gr_wakeup,
1936	.pullup         = gr_pullup,
1937	.udc_start	= gr_udc_start,
1938	.udc_stop	= gr_udc_stop,
1939	/* Other operations not supported */
1940};
1941
1942/* ---------------------------------------------------------------------- */
1943/* Module probe, removal and of-matching */
1944
1945static const char * const onames[] = {
1946	"ep0out", "ep1out", "ep2out", "ep3out", "ep4out", "ep5out",
1947	"ep6out", "ep7out", "ep8out", "ep9out", "ep10out", "ep11out",
1948	"ep12out", "ep13out", "ep14out", "ep15out"
1949};
1950
1951static const char * const inames[] = {
1952	"ep0in", "ep1in", "ep2in", "ep3in", "ep4in", "ep5in",
1953	"ep6in", "ep7in", "ep8in", "ep9in", "ep10in", "ep11in",
1954	"ep12in", "ep13in", "ep14in", "ep15in"
1955};
1956
1957/* Must be called with dev->lock held */
1958static int gr_ep_init(struct gr_udc *dev, int num, int is_in, u32 maxplimit)
1959{
1960	struct gr_ep *ep;
1961	struct gr_request *req;
1962	struct usb_request *_req;
1963	void *buf;
1964
1965	if (is_in) {
1966		ep = &dev->epi[num];
1967		ep->ep.name = inames[num];
1968		ep->regs = &dev->regs->epi[num];
1969	} else {
1970		ep = &dev->epo[num];
1971		ep->ep.name = onames[num];
1972		ep->regs = &dev->regs->epo[num];
1973	}
1974
1975	gr_ep_reset(ep);
1976	ep->num = num;
1977	ep->is_in = is_in;
1978	ep->dev = dev;
1979	ep->ep.ops = &gr_ep_ops;
1980	INIT_LIST_HEAD(&ep->queue);
1981
1982	if (num == 0) {
1983		_req = gr_alloc_request(&ep->ep, GFP_ATOMIC);
1984		if (!_req)
1985			return -ENOMEM;
1986
1987		buf = devm_kzalloc(dev->dev, PAGE_SIZE, GFP_DMA | GFP_ATOMIC);
1988		if (!buf) {
1989			gr_free_request(&ep->ep, _req);
1990			return -ENOMEM;
1991		}
1992
1993		req = container_of(_req, struct gr_request, req);
1994		req->req.buf = buf;
1995		req->req.length = MAX_CTRL_PL_SIZE;
1996
1997		if (is_in)
1998			dev->ep0reqi = req; /* Complete gets set as used */
1999		else
2000			dev->ep0reqo = req; /* Completion treated separately */
2001
2002		usb_ep_set_maxpacket_limit(&ep->ep, MAX_CTRL_PL_SIZE);
2003		ep->bytes_per_buffer = MAX_CTRL_PL_SIZE;
2004
2005		ep->ep.caps.type_control = true;
2006	} else {
2007		usb_ep_set_maxpacket_limit(&ep->ep, (u16)maxplimit);
2008		list_add_tail(&ep->ep.ep_list, &dev->gadget.ep_list);
2009
2010		ep->ep.caps.type_iso = true;
2011		ep->ep.caps.type_bulk = true;
2012		ep->ep.caps.type_int = true;
2013	}
2014	list_add_tail(&ep->ep_list, &dev->ep_list);
2015
2016	if (is_in)
2017		ep->ep.caps.dir_in = true;
2018	else
2019		ep->ep.caps.dir_out = true;
2020
2021	ep->tailbuf = dma_alloc_coherent(dev->dev, ep->ep.maxpacket_limit,
2022					 &ep->tailbuf_paddr, GFP_ATOMIC);
2023	if (!ep->tailbuf)
2024		return -ENOMEM;
2025
2026	return 0;
2027}
2028
2029/* Must be called with dev->lock held */
2030static int gr_udc_init(struct gr_udc *dev)
2031{
2032	struct device_node *np = dev->dev->of_node;
2033	u32 epctrl_val;
2034	u32 dmactrl_val;
2035	int i;
2036	int ret = 0;
2037	u32 bufsize;
2038
2039	gr_set_address(dev, 0);
2040
2041	INIT_LIST_HEAD(&dev->gadget.ep_list);
2042	dev->gadget.speed = USB_SPEED_UNKNOWN;
2043	dev->gadget.ep0 = &dev->epi[0].ep;
2044
2045	INIT_LIST_HEAD(&dev->ep_list);
2046	gr_set_ep0state(dev, GR_EP0_DISCONNECT);
2047
2048	for (i = 0; i < dev->nepo; i++) {
2049		if (of_property_read_u32_index(np, "epobufsizes", i, &bufsize))
2050			bufsize = 1024;
2051		ret = gr_ep_init(dev, i, 0, bufsize);
2052		if (ret)
2053			return ret;
2054	}
2055
2056	for (i = 0; i < dev->nepi; i++) {
2057		if (of_property_read_u32_index(np, "epibufsizes", i, &bufsize))
2058			bufsize = 1024;
2059		ret = gr_ep_init(dev, i, 1, bufsize);
2060		if (ret)
2061			return ret;
2062	}
2063
2064	/* Must be disabled by default */
2065	dev->remote_wakeup = 0;
2066
2067	/* Enable ep0out and ep0in */
2068	epctrl_val = (MAX_CTRL_PL_SIZE << GR_EPCTRL_MAXPL_POS) | GR_EPCTRL_EV;
2069	dmactrl_val = GR_DMACTRL_IE | GR_DMACTRL_AI;
2070	gr_write32(&dev->epo[0].regs->epctrl, epctrl_val);
2071	gr_write32(&dev->epi[0].regs->epctrl, epctrl_val | GR_EPCTRL_PI);
2072	gr_write32(&dev->epo[0].regs->dmactrl, dmactrl_val);
2073	gr_write32(&dev->epi[0].regs->dmactrl, dmactrl_val);
2074
2075	return 0;
2076}
2077
2078static void gr_ep_remove(struct gr_udc *dev, int num, int is_in)
2079{
2080	struct gr_ep *ep;
2081
2082	if (is_in)
2083		ep = &dev->epi[num];
2084	else
2085		ep = &dev->epo[num];
2086
2087	if (ep->tailbuf)
2088		dma_free_coherent(dev->dev, ep->ep.maxpacket_limit,
2089				  ep->tailbuf, ep->tailbuf_paddr);
2090}
2091
2092static void gr_remove(struct platform_device *pdev)
2093{
2094	struct gr_udc *dev = platform_get_drvdata(pdev);
2095	int i;
2096
2097	if (dev->added)
2098		usb_del_gadget_udc(&dev->gadget); /* Shuts everything down */
2099	if (dev->driver) {
2100		dev_err(&pdev->dev,
2101			"Driver still in use but removing anyhow\n");
2102		return;
2103	}
2104
2105	gr_dfs_delete(dev);
2106	dma_pool_destroy(dev->desc_pool);
2107	platform_set_drvdata(pdev, NULL);
2108
2109	gr_free_request(&dev->epi[0].ep, &dev->ep0reqi->req);
2110	gr_free_request(&dev->epo[0].ep, &dev->ep0reqo->req);
2111
2112	for (i = 0; i < dev->nepo; i++)
2113		gr_ep_remove(dev, i, 0);
2114	for (i = 0; i < dev->nepi; i++)
2115		gr_ep_remove(dev, i, 1);
2116}
2117static int gr_request_irq(struct gr_udc *dev, int irq)
2118{
2119	return devm_request_threaded_irq(dev->dev, irq, gr_irq, gr_irq_handler,
2120					 IRQF_SHARED, driver_name, dev);
2121}
2122
2123static int gr_probe(struct platform_device *pdev)
2124{
2125	struct gr_udc *dev;
2126	struct gr_regs __iomem *regs;
2127	int retval;
2128	u32 status;
2129
2130	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
2131	if (!dev)
2132		return -ENOMEM;
2133	dev->dev = &pdev->dev;
2134
2135	regs = devm_platform_ioremap_resource(pdev, 0);
2136	if (IS_ERR(regs))
2137		return PTR_ERR(regs);
2138
2139	dev->irq = platform_get_irq(pdev, 0);
2140	if (dev->irq < 0)
2141		return dev->irq;
2142
2143	/* Some core configurations has separate irqs for IN and OUT events */
2144	dev->irqi = platform_get_irq(pdev, 1);
2145	if (dev->irqi > 0) {
2146		dev->irqo = platform_get_irq(pdev, 2);
2147		if (dev->irqo < 0)
2148			return dev->irqo;
2149	} else {
2150		dev->irqi = 0;
2151	}
2152
2153	dev->gadget.name = driver_name;
2154	dev->gadget.max_speed = USB_SPEED_HIGH;
2155	dev->gadget.ops = &gr_ops;
2156
2157	spin_lock_init(&dev->lock);
2158	dev->regs = regs;
2159
2160	platform_set_drvdata(pdev, dev);
2161
2162	/* Determine number of endpoints and data interface mode */
2163	status = gr_read32(&dev->regs->status);
2164	dev->nepi = ((status & GR_STATUS_NEPI_MASK) >> GR_STATUS_NEPI_POS) + 1;
2165	dev->nepo = ((status & GR_STATUS_NEPO_MASK) >> GR_STATUS_NEPO_POS) + 1;
2166
2167	if (!(status & GR_STATUS_DM)) {
2168		dev_err(dev->dev, "Slave mode cores are not supported\n");
2169		return -ENODEV;
2170	}
2171
2172	/* --- Effects of the following calls might need explicit cleanup --- */
2173
2174	/* Create DMA pool for descriptors */
2175	dev->desc_pool = dma_pool_create("desc_pool", dev->dev,
2176					 sizeof(struct gr_dma_desc), 4, 0);
2177	if (!dev->desc_pool) {
2178		dev_err(dev->dev, "Could not allocate DMA pool");
2179		return -ENOMEM;
2180	}
2181
2182	/* Inside lock so that no gadget can use this udc until probe is done */
2183	retval = usb_add_gadget_udc(dev->dev, &dev->gadget);
2184	if (retval) {
2185		dev_err(dev->dev, "Could not add gadget udc");
2186		goto out;
2187	}
2188	dev->added = 1;
2189
2190	spin_lock(&dev->lock);
2191
2192	retval = gr_udc_init(dev);
2193	if (retval) {
2194		spin_unlock(&dev->lock);
2195		goto out;
2196	}
2197
2198	/* Clear all interrupt enables that might be left on since last boot */
2199	gr_disable_interrupts_and_pullup(dev);
2200
2201	spin_unlock(&dev->lock);
2202
2203	gr_dfs_create(dev);
2204
2205	retval = gr_request_irq(dev, dev->irq);
2206	if (retval) {
2207		dev_err(dev->dev, "Failed to request irq %d\n", dev->irq);
2208		goto out;
2209	}
2210
2211	if (dev->irqi) {
2212		retval = gr_request_irq(dev, dev->irqi);
2213		if (retval) {
2214			dev_err(dev->dev, "Failed to request irqi %d\n",
2215				dev->irqi);
2216			goto out;
2217		}
2218		retval = gr_request_irq(dev, dev->irqo);
2219		if (retval) {
2220			dev_err(dev->dev, "Failed to request irqo %d\n",
2221				dev->irqo);
2222			goto out;
2223		}
2224	}
2225
2226	if (dev->irqi)
2227		dev_info(dev->dev, "regs: %p, irqs %d, %d, %d\n", dev->regs,
2228			 dev->irq, dev->irqi, dev->irqo);
2229	else
2230		dev_info(dev->dev, "regs: %p, irq %d\n", dev->regs, dev->irq);
2231
2232out:
2233	if (retval)
2234		gr_remove(pdev);
2235
2236	return retval;
2237}
2238
2239static const struct of_device_id gr_match[] = {
2240	{.name = "GAISLER_USBDC"},
2241	{.name = "01_021"},
2242	{},
2243};
2244MODULE_DEVICE_TABLE(of, gr_match);
2245
2246static struct platform_driver gr_driver = {
2247	.driver = {
2248		.name = DRIVER_NAME,
2249		.of_match_table = gr_match,
2250	},
2251	.probe = gr_probe,
2252	.remove_new = gr_remove,
2253};
2254module_platform_driver(gr_driver);
2255
2256MODULE_AUTHOR("Aeroflex Gaisler AB.");
2257MODULE_DESCRIPTION(DRIVER_DESC);
2258MODULE_LICENSE("GPL");
2259