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