xref: /linux/drivers/usb/gadget/function/f_sourcesink.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * f_sourcesink.c - USB peripheral source/sink configuration driver
3  *
4  * Copyright (C) 2003-2008 David Brownell
5  * Copyright (C) 2008 by Nokia Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 
13 /* #define VERBOSE_DEBUG */
14 
15 #include <linux/slab.h>
16 #include <linux/kernel.h>
17 #include <linux/device.h>
18 #include <linux/module.h>
19 #include <linux/usb/composite.h>
20 #include <linux/err.h>
21 
22 #include "g_zero.h"
23 #include "u_f.h"
24 
25 /*
26  * SOURCE/SINK FUNCTION ... a primary testing vehicle for USB peripheral
27  * controller drivers.
28  *
29  * This just sinks bulk packets OUT to the peripheral and sources them IN
30  * to the host, optionally with specific data patterns for integrity tests.
31  * As such it supports basic functionality and load tests.
32  *
33  * In terms of control messaging, this supports all the standard requests
34  * plus two that support control-OUT tests.  If the optional "autoresume"
35  * mode is enabled, it provides good functional coverage for the "USBCV"
36  * test harness from USB-IF.
37  *
38  * Note that because this doesn't queue more than one request at a time,
39  * some other function must be used to test queueing logic.  The network
40  * link (g_ether) is the best overall option for that, since its TX and RX
41  * queues are relatively independent, will receive a range of packet sizes,
42  * and can often be made to run out completely.  Those issues are important
43  * when stress testing peripheral controller drivers.
44  */
45 struct f_sourcesink {
46 	struct usb_function	function;
47 
48 	struct usb_ep		*in_ep;
49 	struct usb_ep		*out_ep;
50 	struct usb_ep		*iso_in_ep;
51 	struct usb_ep		*iso_out_ep;
52 	int			cur_alt;
53 };
54 
55 static inline struct f_sourcesink *func_to_ss(struct usb_function *f)
56 {
57 	return container_of(f, struct f_sourcesink, function);
58 }
59 
60 static unsigned pattern;
61 static unsigned isoc_interval;
62 static unsigned isoc_maxpacket;
63 static unsigned isoc_mult;
64 static unsigned isoc_maxburst;
65 static unsigned buflen;
66 
67 /*-------------------------------------------------------------------------*/
68 
69 static struct usb_interface_descriptor source_sink_intf_alt0 = {
70 	.bLength =		USB_DT_INTERFACE_SIZE,
71 	.bDescriptorType =	USB_DT_INTERFACE,
72 
73 	.bAlternateSetting =	0,
74 	.bNumEndpoints =	2,
75 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
76 	/* .iInterface		= DYNAMIC */
77 };
78 
79 static struct usb_interface_descriptor source_sink_intf_alt1 = {
80 	.bLength =		USB_DT_INTERFACE_SIZE,
81 	.bDescriptorType =	USB_DT_INTERFACE,
82 
83 	.bAlternateSetting =	1,
84 	.bNumEndpoints =	4,
85 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
86 	/* .iInterface		= DYNAMIC */
87 };
88 
89 /* full speed support: */
90 
91 static struct usb_endpoint_descriptor fs_source_desc = {
92 	.bLength =		USB_DT_ENDPOINT_SIZE,
93 	.bDescriptorType =	USB_DT_ENDPOINT,
94 
95 	.bEndpointAddress =	USB_DIR_IN,
96 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
97 };
98 
99 static struct usb_endpoint_descriptor fs_sink_desc = {
100 	.bLength =		USB_DT_ENDPOINT_SIZE,
101 	.bDescriptorType =	USB_DT_ENDPOINT,
102 
103 	.bEndpointAddress =	USB_DIR_OUT,
104 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
105 };
106 
107 static struct usb_endpoint_descriptor fs_iso_source_desc = {
108 	.bLength =		USB_DT_ENDPOINT_SIZE,
109 	.bDescriptorType =	USB_DT_ENDPOINT,
110 
111 	.bEndpointAddress =	USB_DIR_IN,
112 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
113 	.wMaxPacketSize =	cpu_to_le16(1023),
114 	.bInterval =		4,
115 };
116 
117 static struct usb_endpoint_descriptor fs_iso_sink_desc = {
118 	.bLength =		USB_DT_ENDPOINT_SIZE,
119 	.bDescriptorType =	USB_DT_ENDPOINT,
120 
121 	.bEndpointAddress =	USB_DIR_OUT,
122 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
123 	.wMaxPacketSize =	cpu_to_le16(1023),
124 	.bInterval =		4,
125 };
126 
127 static struct usb_descriptor_header *fs_source_sink_descs[] = {
128 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
129 	(struct usb_descriptor_header *) &fs_sink_desc,
130 	(struct usb_descriptor_header *) &fs_source_desc,
131 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
132 #define FS_ALT_IFC_1_OFFSET	3
133 	(struct usb_descriptor_header *) &fs_sink_desc,
134 	(struct usb_descriptor_header *) &fs_source_desc,
135 	(struct usb_descriptor_header *) &fs_iso_sink_desc,
136 	(struct usb_descriptor_header *) &fs_iso_source_desc,
137 	NULL,
138 };
139 
140 /* high speed support: */
141 
142 static struct usb_endpoint_descriptor hs_source_desc = {
143 	.bLength =		USB_DT_ENDPOINT_SIZE,
144 	.bDescriptorType =	USB_DT_ENDPOINT,
145 
146 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
147 	.wMaxPacketSize =	cpu_to_le16(512),
148 };
149 
150 static struct usb_endpoint_descriptor hs_sink_desc = {
151 	.bLength =		USB_DT_ENDPOINT_SIZE,
152 	.bDescriptorType =	USB_DT_ENDPOINT,
153 
154 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
155 	.wMaxPacketSize =	cpu_to_le16(512),
156 };
157 
158 static struct usb_endpoint_descriptor hs_iso_source_desc = {
159 	.bLength =		USB_DT_ENDPOINT_SIZE,
160 	.bDescriptorType =	USB_DT_ENDPOINT,
161 
162 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
163 	.wMaxPacketSize =	cpu_to_le16(1024),
164 	.bInterval =		4,
165 };
166 
167 static struct usb_endpoint_descriptor hs_iso_sink_desc = {
168 	.bLength =		USB_DT_ENDPOINT_SIZE,
169 	.bDescriptorType =	USB_DT_ENDPOINT,
170 
171 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
172 	.wMaxPacketSize =	cpu_to_le16(1024),
173 	.bInterval =		4,
174 };
175 
176 static struct usb_descriptor_header *hs_source_sink_descs[] = {
177 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
178 	(struct usb_descriptor_header *) &hs_source_desc,
179 	(struct usb_descriptor_header *) &hs_sink_desc,
180 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
181 #define HS_ALT_IFC_1_OFFSET	3
182 	(struct usb_descriptor_header *) &hs_source_desc,
183 	(struct usb_descriptor_header *) &hs_sink_desc,
184 	(struct usb_descriptor_header *) &hs_iso_source_desc,
185 	(struct usb_descriptor_header *) &hs_iso_sink_desc,
186 	NULL,
187 };
188 
189 /* super speed support: */
190 
191 static struct usb_endpoint_descriptor ss_source_desc = {
192 	.bLength =		USB_DT_ENDPOINT_SIZE,
193 	.bDescriptorType =	USB_DT_ENDPOINT,
194 
195 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
196 	.wMaxPacketSize =	cpu_to_le16(1024),
197 };
198 
199 static struct usb_ss_ep_comp_descriptor ss_source_comp_desc = {
200 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
201 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
202 
203 	.bMaxBurst =		0,
204 	.bmAttributes =		0,
205 	.wBytesPerInterval =	0,
206 };
207 
208 static struct usb_endpoint_descriptor ss_sink_desc = {
209 	.bLength =		USB_DT_ENDPOINT_SIZE,
210 	.bDescriptorType =	USB_DT_ENDPOINT,
211 
212 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
213 	.wMaxPacketSize =	cpu_to_le16(1024),
214 };
215 
216 static struct usb_ss_ep_comp_descriptor ss_sink_comp_desc = {
217 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
218 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
219 
220 	.bMaxBurst =		0,
221 	.bmAttributes =		0,
222 	.wBytesPerInterval =	0,
223 };
224 
225 static struct usb_endpoint_descriptor ss_iso_source_desc = {
226 	.bLength =		USB_DT_ENDPOINT_SIZE,
227 	.bDescriptorType =	USB_DT_ENDPOINT,
228 
229 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
230 	.wMaxPacketSize =	cpu_to_le16(1024),
231 	.bInterval =		4,
232 };
233 
234 static struct usb_ss_ep_comp_descriptor ss_iso_source_comp_desc = {
235 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
236 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
237 
238 	.bMaxBurst =		0,
239 	.bmAttributes =		0,
240 	.wBytesPerInterval =	cpu_to_le16(1024),
241 };
242 
243 static struct usb_endpoint_descriptor ss_iso_sink_desc = {
244 	.bLength =		USB_DT_ENDPOINT_SIZE,
245 	.bDescriptorType =	USB_DT_ENDPOINT,
246 
247 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
248 	.wMaxPacketSize =	cpu_to_le16(1024),
249 	.bInterval =		4,
250 };
251 
252 static struct usb_ss_ep_comp_descriptor ss_iso_sink_comp_desc = {
253 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
254 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
255 
256 	.bMaxBurst =		0,
257 	.bmAttributes =		0,
258 	.wBytesPerInterval =	cpu_to_le16(1024),
259 };
260 
261 static struct usb_descriptor_header *ss_source_sink_descs[] = {
262 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
263 	(struct usb_descriptor_header *) &ss_source_desc,
264 	(struct usb_descriptor_header *) &ss_source_comp_desc,
265 	(struct usb_descriptor_header *) &ss_sink_desc,
266 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
267 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
268 #define SS_ALT_IFC_1_OFFSET	5
269 	(struct usb_descriptor_header *) &ss_source_desc,
270 	(struct usb_descriptor_header *) &ss_source_comp_desc,
271 	(struct usb_descriptor_header *) &ss_sink_desc,
272 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
273 	(struct usb_descriptor_header *) &ss_iso_source_desc,
274 	(struct usb_descriptor_header *) &ss_iso_source_comp_desc,
275 	(struct usb_descriptor_header *) &ss_iso_sink_desc,
276 	(struct usb_descriptor_header *) &ss_iso_sink_comp_desc,
277 	NULL,
278 };
279 
280 /* function-specific strings: */
281 
282 static struct usb_string strings_sourcesink[] = {
283 	[0].s = "source and sink data",
284 	{  }			/* end of list */
285 };
286 
287 static struct usb_gadget_strings stringtab_sourcesink = {
288 	.language	= 0x0409,	/* en-us */
289 	.strings	= strings_sourcesink,
290 };
291 
292 static struct usb_gadget_strings *sourcesink_strings[] = {
293 	&stringtab_sourcesink,
294 	NULL,
295 };
296 
297 /*-------------------------------------------------------------------------*/
298 
299 static inline struct usb_request *ss_alloc_ep_req(struct usb_ep *ep, int len)
300 {
301 	return alloc_ep_req(ep, len, buflen);
302 }
303 
304 void free_ep_req(struct usb_ep *ep, struct usb_request *req)
305 {
306 	kfree(req->buf);
307 	usb_ep_free_request(ep, req);
308 }
309 
310 static void disable_ep(struct usb_composite_dev *cdev, struct usb_ep *ep)
311 {
312 	int			value;
313 
314 	if (ep->driver_data) {
315 		value = usb_ep_disable(ep);
316 		if (value < 0)
317 			DBG(cdev, "disable %s --> %d\n",
318 					ep->name, value);
319 		ep->driver_data = NULL;
320 	}
321 }
322 
323 void disable_endpoints(struct usb_composite_dev *cdev,
324 		struct usb_ep *in, struct usb_ep *out,
325 		struct usb_ep *iso_in, struct usb_ep *iso_out)
326 {
327 	disable_ep(cdev, in);
328 	disable_ep(cdev, out);
329 	if (iso_in)
330 		disable_ep(cdev, iso_in);
331 	if (iso_out)
332 		disable_ep(cdev, iso_out);
333 }
334 
335 static int
336 sourcesink_bind(struct usb_configuration *c, struct usb_function *f)
337 {
338 	struct usb_composite_dev *cdev = c->cdev;
339 	struct f_sourcesink	*ss = func_to_ss(f);
340 	int	id;
341 	int ret;
342 
343 	/* allocate interface ID(s) */
344 	id = usb_interface_id(c, f);
345 	if (id < 0)
346 		return id;
347 	source_sink_intf_alt0.bInterfaceNumber = id;
348 	source_sink_intf_alt1.bInterfaceNumber = id;
349 
350 	/* allocate bulk endpoints */
351 	ss->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_source_desc);
352 	if (!ss->in_ep) {
353 autoconf_fail:
354 		ERROR(cdev, "%s: can't autoconfigure on %s\n",
355 			f->name, cdev->gadget->name);
356 		return -ENODEV;
357 	}
358 	ss->in_ep->driver_data = cdev;	/* claim */
359 
360 	ss->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_sink_desc);
361 	if (!ss->out_ep)
362 		goto autoconf_fail;
363 	ss->out_ep->driver_data = cdev;	/* claim */
364 
365 	/* sanity check the isoc module parameters */
366 	if (isoc_interval < 1)
367 		isoc_interval = 1;
368 	if (isoc_interval > 16)
369 		isoc_interval = 16;
370 	if (isoc_mult > 2)
371 		isoc_mult = 2;
372 	if (isoc_maxburst > 15)
373 		isoc_maxburst = 15;
374 
375 	/* fill in the FS isoc descriptors from the module parameters */
376 	fs_iso_source_desc.wMaxPacketSize = isoc_maxpacket > 1023 ?
377 						1023 : isoc_maxpacket;
378 	fs_iso_source_desc.bInterval = isoc_interval;
379 	fs_iso_sink_desc.wMaxPacketSize = isoc_maxpacket > 1023 ?
380 						1023 : isoc_maxpacket;
381 	fs_iso_sink_desc.bInterval = isoc_interval;
382 
383 	/* allocate iso endpoints */
384 	ss->iso_in_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_source_desc);
385 	if (!ss->iso_in_ep)
386 		goto no_iso;
387 	ss->iso_in_ep->driver_data = cdev;	/* claim */
388 
389 	ss->iso_out_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_sink_desc);
390 	if (ss->iso_out_ep) {
391 		ss->iso_out_ep->driver_data = cdev;	/* claim */
392 	} else {
393 		ss->iso_in_ep->driver_data = NULL;
394 		ss->iso_in_ep = NULL;
395 no_iso:
396 		/*
397 		 * We still want to work even if the UDC doesn't have isoc
398 		 * endpoints, so null out the alt interface that contains
399 		 * them and continue.
400 		 */
401 		fs_source_sink_descs[FS_ALT_IFC_1_OFFSET] = NULL;
402 		hs_source_sink_descs[HS_ALT_IFC_1_OFFSET] = NULL;
403 		ss_source_sink_descs[SS_ALT_IFC_1_OFFSET] = NULL;
404 	}
405 
406 	if (isoc_maxpacket > 1024)
407 		isoc_maxpacket = 1024;
408 
409 	/* support high speed hardware */
410 	hs_source_desc.bEndpointAddress = fs_source_desc.bEndpointAddress;
411 	hs_sink_desc.bEndpointAddress = fs_sink_desc.bEndpointAddress;
412 
413 	/*
414 	 * Fill in the HS isoc descriptors from the module parameters.
415 	 * We assume that the user knows what they are doing and won't
416 	 * give parameters that their UDC doesn't support.
417 	 */
418 	hs_iso_source_desc.wMaxPacketSize = isoc_maxpacket;
419 	hs_iso_source_desc.wMaxPacketSize |= isoc_mult << 11;
420 	hs_iso_source_desc.bInterval = isoc_interval;
421 	hs_iso_source_desc.bEndpointAddress =
422 		fs_iso_source_desc.bEndpointAddress;
423 
424 	hs_iso_sink_desc.wMaxPacketSize = isoc_maxpacket;
425 	hs_iso_sink_desc.wMaxPacketSize |= isoc_mult << 11;
426 	hs_iso_sink_desc.bInterval = isoc_interval;
427 	hs_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
428 
429 	/* support super speed hardware */
430 	ss_source_desc.bEndpointAddress =
431 		fs_source_desc.bEndpointAddress;
432 	ss_sink_desc.bEndpointAddress =
433 		fs_sink_desc.bEndpointAddress;
434 
435 	/*
436 	 * Fill in the SS isoc descriptors from the module parameters.
437 	 * We assume that the user knows what they are doing and won't
438 	 * give parameters that their UDC doesn't support.
439 	 */
440 	ss_iso_source_desc.wMaxPacketSize = isoc_maxpacket;
441 	ss_iso_source_desc.bInterval = isoc_interval;
442 	ss_iso_source_comp_desc.bmAttributes = isoc_mult;
443 	ss_iso_source_comp_desc.bMaxBurst = isoc_maxburst;
444 	ss_iso_source_comp_desc.wBytesPerInterval =
445 		isoc_maxpacket * (isoc_mult + 1) * (isoc_maxburst + 1);
446 	ss_iso_source_desc.bEndpointAddress =
447 		fs_iso_source_desc.bEndpointAddress;
448 
449 	ss_iso_sink_desc.wMaxPacketSize = isoc_maxpacket;
450 	ss_iso_sink_desc.bInterval = isoc_interval;
451 	ss_iso_sink_comp_desc.bmAttributes = isoc_mult;
452 	ss_iso_sink_comp_desc.bMaxBurst = isoc_maxburst;
453 	ss_iso_sink_comp_desc.wBytesPerInterval =
454 		isoc_maxpacket * (isoc_mult + 1) * (isoc_maxburst + 1);
455 	ss_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
456 
457 	ret = usb_assign_descriptors(f, fs_source_sink_descs,
458 			hs_source_sink_descs, ss_source_sink_descs);
459 	if (ret)
460 		return ret;
461 
462 	DBG(cdev, "%s speed %s: IN/%s, OUT/%s, ISO-IN/%s, ISO-OUT/%s\n",
463 	    (gadget_is_superspeed(c->cdev->gadget) ? "super" :
464 	     (gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full")),
465 			f->name, ss->in_ep->name, ss->out_ep->name,
466 			ss->iso_in_ep ? ss->iso_in_ep->name : "<none>",
467 			ss->iso_out_ep ? ss->iso_out_ep->name : "<none>");
468 	return 0;
469 }
470 
471 static void
472 sourcesink_free_func(struct usb_function *f)
473 {
474 	struct f_ss_opts *opts;
475 
476 	opts = container_of(f->fi, struct f_ss_opts, func_inst);
477 
478 	mutex_lock(&opts->lock);
479 	opts->refcnt--;
480 	mutex_unlock(&opts->lock);
481 
482 	usb_free_all_descriptors(f);
483 	kfree(func_to_ss(f));
484 }
485 
486 /* optionally require specific source/sink data patterns  */
487 static int check_read_data(struct f_sourcesink *ss, struct usb_request *req)
488 {
489 	unsigned		i;
490 	u8			*buf = req->buf;
491 	struct usb_composite_dev *cdev = ss->function.config->cdev;
492 
493 	if (pattern == 2)
494 		return 0;
495 
496 	for (i = 0; i < req->actual; i++, buf++) {
497 		switch (pattern) {
498 
499 		/* all-zeroes has no synchronization issues */
500 		case 0:
501 			if (*buf == 0)
502 				continue;
503 			break;
504 
505 		/* "mod63" stays in sync with short-terminated transfers,
506 		 * OR otherwise when host and gadget agree on how large
507 		 * each usb transfer request should be.  Resync is done
508 		 * with set_interface or set_config.  (We *WANT* it to
509 		 * get quickly out of sync if controllers or their drivers
510 		 * stutter for any reason, including buffer duplication...)
511 		 */
512 		case 1:
513 			if (*buf == (u8)(i % 63))
514 				continue;
515 			break;
516 		}
517 		ERROR(cdev, "bad OUT byte, buf[%d] = %d\n", i, *buf);
518 		usb_ep_set_halt(ss->out_ep);
519 		return -EINVAL;
520 	}
521 	return 0;
522 }
523 
524 static void reinit_write_data(struct usb_ep *ep, struct usb_request *req)
525 {
526 	unsigned	i;
527 	u8		*buf = req->buf;
528 
529 	switch (pattern) {
530 	case 0:
531 		memset(req->buf, 0, req->length);
532 		break;
533 	case 1:
534 		for  (i = 0; i < req->length; i++)
535 			*buf++ = (u8) (i % 63);
536 		break;
537 	case 2:
538 		break;
539 	}
540 }
541 
542 static void source_sink_complete(struct usb_ep *ep, struct usb_request *req)
543 {
544 	struct usb_composite_dev	*cdev;
545 	struct f_sourcesink		*ss = ep->driver_data;
546 	int				status = req->status;
547 
548 	/* driver_data will be null if ep has been disabled */
549 	if (!ss)
550 		return;
551 
552 	cdev = ss->function.config->cdev;
553 
554 	switch (status) {
555 
556 	case 0:				/* normal completion? */
557 		if (ep == ss->out_ep) {
558 			check_read_data(ss, req);
559 			if (pattern != 2)
560 				memset(req->buf, 0x55, req->length);
561 		}
562 		break;
563 
564 	/* this endpoint is normally active while we're configured */
565 	case -ECONNABORTED:		/* hardware forced ep reset */
566 	case -ECONNRESET:		/* request dequeued */
567 	case -ESHUTDOWN:		/* disconnect from host */
568 		VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
569 				req->actual, req->length);
570 		if (ep == ss->out_ep)
571 			check_read_data(ss, req);
572 		free_ep_req(ep, req);
573 		return;
574 
575 	case -EOVERFLOW:		/* buffer overrun on read means that
576 					 * we didn't provide a big enough
577 					 * buffer.
578 					 */
579 	default:
580 #if 1
581 		DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
582 				status, req->actual, req->length);
583 #endif
584 	case -EREMOTEIO:		/* short read */
585 		break;
586 	}
587 
588 	status = usb_ep_queue(ep, req, GFP_ATOMIC);
589 	if (status) {
590 		ERROR(cdev, "kill %s:  resubmit %d bytes --> %d\n",
591 				ep->name, req->length, status);
592 		usb_ep_set_halt(ep);
593 		/* FIXME recover later ... somehow */
594 	}
595 }
596 
597 static int source_sink_start_ep(struct f_sourcesink *ss, bool is_in,
598 		bool is_iso, int speed)
599 {
600 	struct usb_ep		*ep;
601 	struct usb_request	*req;
602 	int			i, size, status;
603 
604 	for (i = 0; i < 8; i++) {
605 		if (is_iso) {
606 			switch (speed) {
607 			case USB_SPEED_SUPER:
608 				size = isoc_maxpacket * (isoc_mult + 1) *
609 						(isoc_maxburst + 1);
610 				break;
611 			case USB_SPEED_HIGH:
612 				size = isoc_maxpacket * (isoc_mult + 1);
613 				break;
614 			default:
615 				size = isoc_maxpacket > 1023 ?
616 						1023 : isoc_maxpacket;
617 				break;
618 			}
619 			ep = is_in ? ss->iso_in_ep : ss->iso_out_ep;
620 			req = ss_alloc_ep_req(ep, size);
621 		} else {
622 			ep = is_in ? ss->in_ep : ss->out_ep;
623 			req = ss_alloc_ep_req(ep, 0);
624 		}
625 
626 		if (!req)
627 			return -ENOMEM;
628 
629 		req->complete = source_sink_complete;
630 		if (is_in)
631 			reinit_write_data(ep, req);
632 		else if (pattern != 2)
633 			memset(req->buf, 0x55, req->length);
634 
635 		status = usb_ep_queue(ep, req, GFP_ATOMIC);
636 		if (status) {
637 			struct usb_composite_dev	*cdev;
638 
639 			cdev = ss->function.config->cdev;
640 			ERROR(cdev, "start %s%s %s --> %d\n",
641 			      is_iso ? "ISO-" : "", is_in ? "IN" : "OUT",
642 			      ep->name, status);
643 			free_ep_req(ep, req);
644 		}
645 
646 		if (!is_iso)
647 			break;
648 	}
649 
650 	return status;
651 }
652 
653 static void disable_source_sink(struct f_sourcesink *ss)
654 {
655 	struct usb_composite_dev	*cdev;
656 
657 	cdev = ss->function.config->cdev;
658 	disable_endpoints(cdev, ss->in_ep, ss->out_ep, ss->iso_in_ep,
659 			ss->iso_out_ep);
660 	VDBG(cdev, "%s disabled\n", ss->function.name);
661 }
662 
663 static int
664 enable_source_sink(struct usb_composite_dev *cdev, struct f_sourcesink *ss,
665 		int alt)
666 {
667 	int					result = 0;
668 	int					speed = cdev->gadget->speed;
669 	struct usb_ep				*ep;
670 
671 	/* one bulk endpoint writes (sources) zeroes IN (to the host) */
672 	ep = ss->in_ep;
673 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
674 	if (result)
675 		return result;
676 	result = usb_ep_enable(ep);
677 	if (result < 0)
678 		return result;
679 	ep->driver_data = ss;
680 
681 	result = source_sink_start_ep(ss, true, false, speed);
682 	if (result < 0) {
683 fail:
684 		ep = ss->in_ep;
685 		usb_ep_disable(ep);
686 		ep->driver_data = NULL;
687 		return result;
688 	}
689 
690 	/* one bulk endpoint reads (sinks) anything OUT (from the host) */
691 	ep = ss->out_ep;
692 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
693 	if (result)
694 		goto fail;
695 	result = usb_ep_enable(ep);
696 	if (result < 0)
697 		goto fail;
698 	ep->driver_data = ss;
699 
700 	result = source_sink_start_ep(ss, false, false, speed);
701 	if (result < 0) {
702 fail2:
703 		ep = ss->out_ep;
704 		usb_ep_disable(ep);
705 		ep->driver_data = NULL;
706 		goto fail;
707 	}
708 
709 	if (alt == 0)
710 		goto out;
711 
712 	/* one iso endpoint writes (sources) zeroes IN (to the host) */
713 	ep = ss->iso_in_ep;
714 	if (ep) {
715 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
716 		if (result)
717 			goto fail2;
718 		result = usb_ep_enable(ep);
719 		if (result < 0)
720 			goto fail2;
721 		ep->driver_data = ss;
722 
723 		result = source_sink_start_ep(ss, true, true, speed);
724 		if (result < 0) {
725 fail3:
726 			ep = ss->iso_in_ep;
727 			if (ep) {
728 				usb_ep_disable(ep);
729 				ep->driver_data = NULL;
730 			}
731 			goto fail2;
732 		}
733 	}
734 
735 	/* one iso endpoint reads (sinks) anything OUT (from the host) */
736 	ep = ss->iso_out_ep;
737 	if (ep) {
738 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
739 		if (result)
740 			goto fail3;
741 		result = usb_ep_enable(ep);
742 		if (result < 0)
743 			goto fail3;
744 		ep->driver_data = ss;
745 
746 		result = source_sink_start_ep(ss, false, true, speed);
747 		if (result < 0) {
748 			usb_ep_disable(ep);
749 			ep->driver_data = NULL;
750 			goto fail3;
751 		}
752 	}
753 out:
754 	ss->cur_alt = alt;
755 
756 	DBG(cdev, "%s enabled, alt intf %d\n", ss->function.name, alt);
757 	return result;
758 }
759 
760 static int sourcesink_set_alt(struct usb_function *f,
761 		unsigned intf, unsigned alt)
762 {
763 	struct f_sourcesink		*ss = func_to_ss(f);
764 	struct usb_composite_dev	*cdev = f->config->cdev;
765 
766 	if (ss->in_ep->driver_data)
767 		disable_source_sink(ss);
768 	return enable_source_sink(cdev, ss, alt);
769 }
770 
771 static int sourcesink_get_alt(struct usb_function *f, unsigned intf)
772 {
773 	struct f_sourcesink		*ss = func_to_ss(f);
774 
775 	return ss->cur_alt;
776 }
777 
778 static void sourcesink_disable(struct usb_function *f)
779 {
780 	struct f_sourcesink	*ss = func_to_ss(f);
781 
782 	disable_source_sink(ss);
783 }
784 
785 /*-------------------------------------------------------------------------*/
786 
787 static int sourcesink_setup(struct usb_function *f,
788 		const struct usb_ctrlrequest *ctrl)
789 {
790 	struct usb_configuration        *c = f->config;
791 	struct usb_request	*req = c->cdev->req;
792 	int			value = -EOPNOTSUPP;
793 	u16			w_index = le16_to_cpu(ctrl->wIndex);
794 	u16			w_value = le16_to_cpu(ctrl->wValue);
795 	u16			w_length = le16_to_cpu(ctrl->wLength);
796 
797 	req->length = USB_COMP_EP0_BUFSIZ;
798 
799 	/* composite driver infrastructure handles everything except
800 	 * the two control test requests.
801 	 */
802 	switch (ctrl->bRequest) {
803 
804 	/*
805 	 * These are the same vendor-specific requests supported by
806 	 * Intel's USB 2.0 compliance test devices.  We exceed that
807 	 * device spec by allowing multiple-packet requests.
808 	 *
809 	 * NOTE:  the Control-OUT data stays in req->buf ... better
810 	 * would be copying it into a scratch buffer, so that other
811 	 * requests may safely intervene.
812 	 */
813 	case 0x5b:	/* control WRITE test -- fill the buffer */
814 		if (ctrl->bRequestType != (USB_DIR_OUT|USB_TYPE_VENDOR))
815 			goto unknown;
816 		if (w_value || w_index)
817 			break;
818 		/* just read that many bytes into the buffer */
819 		if (w_length > req->length)
820 			break;
821 		value = w_length;
822 		break;
823 	case 0x5c:	/* control READ test -- return the buffer */
824 		if (ctrl->bRequestType != (USB_DIR_IN|USB_TYPE_VENDOR))
825 			goto unknown;
826 		if (w_value || w_index)
827 			break;
828 		/* expect those bytes are still in the buffer; send back */
829 		if (w_length > req->length)
830 			break;
831 		value = w_length;
832 		break;
833 
834 	default:
835 unknown:
836 		VDBG(c->cdev,
837 			"unknown control req%02x.%02x v%04x i%04x l%d\n",
838 			ctrl->bRequestType, ctrl->bRequest,
839 			w_value, w_index, w_length);
840 	}
841 
842 	/* respond with data transfer or status phase? */
843 	if (value >= 0) {
844 		VDBG(c->cdev, "source/sink req%02x.%02x v%04x i%04x l%d\n",
845 			ctrl->bRequestType, ctrl->bRequest,
846 			w_value, w_index, w_length);
847 		req->zero = 0;
848 		req->length = value;
849 		value = usb_ep_queue(c->cdev->gadget->ep0, req, GFP_ATOMIC);
850 		if (value < 0)
851 			ERROR(c->cdev, "source/sink response, err %d\n",
852 					value);
853 	}
854 
855 	/* device either stalls (value < 0) or reports success */
856 	return value;
857 }
858 
859 static struct usb_function *source_sink_alloc_func(
860 		struct usb_function_instance *fi)
861 {
862 	struct f_sourcesink     *ss;
863 	struct f_ss_opts	*ss_opts;
864 
865 	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
866 	if (!ss)
867 		return NULL;
868 
869 	ss_opts =  container_of(fi, struct f_ss_opts, func_inst);
870 
871 	mutex_lock(&ss_opts->lock);
872 	ss_opts->refcnt++;
873 	mutex_unlock(&ss_opts->lock);
874 
875 	pattern = ss_opts->pattern;
876 	isoc_interval = ss_opts->isoc_interval;
877 	isoc_maxpacket = ss_opts->isoc_maxpacket;
878 	isoc_mult = ss_opts->isoc_mult;
879 	isoc_maxburst = ss_opts->isoc_maxburst;
880 	buflen = ss_opts->bulk_buflen;
881 
882 	ss->function.name = "source/sink";
883 	ss->function.bind = sourcesink_bind;
884 	ss->function.set_alt = sourcesink_set_alt;
885 	ss->function.get_alt = sourcesink_get_alt;
886 	ss->function.disable = sourcesink_disable;
887 	ss->function.setup = sourcesink_setup;
888 	ss->function.strings = sourcesink_strings;
889 
890 	ss->function.free_func = sourcesink_free_func;
891 
892 	return &ss->function;
893 }
894 
895 static inline struct f_ss_opts *to_f_ss_opts(struct config_item *item)
896 {
897 	return container_of(to_config_group(item), struct f_ss_opts,
898 			    func_inst.group);
899 }
900 
901 CONFIGFS_ATTR_STRUCT(f_ss_opts);
902 CONFIGFS_ATTR_OPS(f_ss_opts);
903 
904 static void ss_attr_release(struct config_item *item)
905 {
906 	struct f_ss_opts *ss_opts = to_f_ss_opts(item);
907 
908 	usb_put_function_instance(&ss_opts->func_inst);
909 }
910 
911 static struct configfs_item_operations ss_item_ops = {
912 	.release		= ss_attr_release,
913 	.show_attribute		= f_ss_opts_attr_show,
914 	.store_attribute	= f_ss_opts_attr_store,
915 };
916 
917 static ssize_t f_ss_opts_pattern_show(struct f_ss_opts *opts, char *page)
918 {
919 	int result;
920 
921 	mutex_lock(&opts->lock);
922 	result = sprintf(page, "%u", opts->pattern);
923 	mutex_unlock(&opts->lock);
924 
925 	return result;
926 }
927 
928 static ssize_t f_ss_opts_pattern_store(struct f_ss_opts *opts,
929 				       const char *page, size_t len)
930 {
931 	int ret;
932 	u8 num;
933 
934 	mutex_lock(&opts->lock);
935 	if (opts->refcnt) {
936 		ret = -EBUSY;
937 		goto end;
938 	}
939 
940 	ret = kstrtou8(page, 0, &num);
941 	if (ret)
942 		goto end;
943 
944 	if (num != 0 && num != 1 && num != 2) {
945 		ret = -EINVAL;
946 		goto end;
947 	}
948 
949 	opts->pattern = num;
950 	ret = len;
951 end:
952 	mutex_unlock(&opts->lock);
953 	return ret;
954 }
955 
956 static struct f_ss_opts_attribute f_ss_opts_pattern =
957 	__CONFIGFS_ATTR(pattern, S_IRUGO | S_IWUSR,
958 			f_ss_opts_pattern_show,
959 			f_ss_opts_pattern_store);
960 
961 static ssize_t f_ss_opts_isoc_interval_show(struct f_ss_opts *opts, char *page)
962 {
963 	int result;
964 
965 	mutex_lock(&opts->lock);
966 	result = sprintf(page, "%u", opts->isoc_interval);
967 	mutex_unlock(&opts->lock);
968 
969 	return result;
970 }
971 
972 static ssize_t f_ss_opts_isoc_interval_store(struct f_ss_opts *opts,
973 				       const char *page, size_t len)
974 {
975 	int ret;
976 	u8 num;
977 
978 	mutex_lock(&opts->lock);
979 	if (opts->refcnt) {
980 		ret = -EBUSY;
981 		goto end;
982 	}
983 
984 	ret = kstrtou8(page, 0, &num);
985 	if (ret)
986 		goto end;
987 
988 	if (num > 16) {
989 		ret = -EINVAL;
990 		goto end;
991 	}
992 
993 	opts->isoc_interval = num;
994 	ret = len;
995 end:
996 	mutex_unlock(&opts->lock);
997 	return ret;
998 }
999 
1000 static struct f_ss_opts_attribute f_ss_opts_isoc_interval =
1001 	__CONFIGFS_ATTR(isoc_interval, S_IRUGO | S_IWUSR,
1002 			f_ss_opts_isoc_interval_show,
1003 			f_ss_opts_isoc_interval_store);
1004 
1005 static ssize_t f_ss_opts_isoc_maxpacket_show(struct f_ss_opts *opts, char *page)
1006 {
1007 	int result;
1008 
1009 	mutex_lock(&opts->lock);
1010 	result = sprintf(page, "%u", opts->isoc_maxpacket);
1011 	mutex_unlock(&opts->lock);
1012 
1013 	return result;
1014 }
1015 
1016 static ssize_t f_ss_opts_isoc_maxpacket_store(struct f_ss_opts *opts,
1017 				       const char *page, size_t len)
1018 {
1019 	int ret;
1020 	u16 num;
1021 
1022 	mutex_lock(&opts->lock);
1023 	if (opts->refcnt) {
1024 		ret = -EBUSY;
1025 		goto end;
1026 	}
1027 
1028 	ret = kstrtou16(page, 0, &num);
1029 	if (ret)
1030 		goto end;
1031 
1032 	if (num > 1024) {
1033 		ret = -EINVAL;
1034 		goto end;
1035 	}
1036 
1037 	opts->isoc_maxpacket = num;
1038 	ret = len;
1039 end:
1040 	mutex_unlock(&opts->lock);
1041 	return ret;
1042 }
1043 
1044 static struct f_ss_opts_attribute f_ss_opts_isoc_maxpacket =
1045 	__CONFIGFS_ATTR(isoc_maxpacket, S_IRUGO | S_IWUSR,
1046 			f_ss_opts_isoc_maxpacket_show,
1047 			f_ss_opts_isoc_maxpacket_store);
1048 
1049 static ssize_t f_ss_opts_isoc_mult_show(struct f_ss_opts *opts, char *page)
1050 {
1051 	int result;
1052 
1053 	mutex_lock(&opts->lock);
1054 	result = sprintf(page, "%u", opts->isoc_mult);
1055 	mutex_unlock(&opts->lock);
1056 
1057 	return result;
1058 }
1059 
1060 static ssize_t f_ss_opts_isoc_mult_store(struct f_ss_opts *opts,
1061 				       const char *page, size_t len)
1062 {
1063 	int ret;
1064 	u8 num;
1065 
1066 	mutex_lock(&opts->lock);
1067 	if (opts->refcnt) {
1068 		ret = -EBUSY;
1069 		goto end;
1070 	}
1071 
1072 	ret = kstrtou8(page, 0, &num);
1073 	if (ret)
1074 		goto end;
1075 
1076 	if (num > 2) {
1077 		ret = -EINVAL;
1078 		goto end;
1079 	}
1080 
1081 	opts->isoc_mult = num;
1082 	ret = len;
1083 end:
1084 	mutex_unlock(&opts->lock);
1085 	return ret;
1086 }
1087 
1088 static struct f_ss_opts_attribute f_ss_opts_isoc_mult =
1089 	__CONFIGFS_ATTR(isoc_mult, S_IRUGO | S_IWUSR,
1090 			f_ss_opts_isoc_mult_show,
1091 			f_ss_opts_isoc_mult_store);
1092 
1093 static ssize_t f_ss_opts_isoc_maxburst_show(struct f_ss_opts *opts, char *page)
1094 {
1095 	int result;
1096 
1097 	mutex_lock(&opts->lock);
1098 	result = sprintf(page, "%u", opts->isoc_maxburst);
1099 	mutex_unlock(&opts->lock);
1100 
1101 	return result;
1102 }
1103 
1104 static ssize_t f_ss_opts_isoc_maxburst_store(struct f_ss_opts *opts,
1105 				       const char *page, size_t len)
1106 {
1107 	int ret;
1108 	u8 num;
1109 
1110 	mutex_lock(&opts->lock);
1111 	if (opts->refcnt) {
1112 		ret = -EBUSY;
1113 		goto end;
1114 	}
1115 
1116 	ret = kstrtou8(page, 0, &num);
1117 	if (ret)
1118 		goto end;
1119 
1120 	if (num > 15) {
1121 		ret = -EINVAL;
1122 		goto end;
1123 	}
1124 
1125 	opts->isoc_maxburst = num;
1126 	ret = len;
1127 end:
1128 	mutex_unlock(&opts->lock);
1129 	return ret;
1130 }
1131 
1132 static struct f_ss_opts_attribute f_ss_opts_isoc_maxburst =
1133 	__CONFIGFS_ATTR(isoc_maxburst, S_IRUGO | S_IWUSR,
1134 			f_ss_opts_isoc_maxburst_show,
1135 			f_ss_opts_isoc_maxburst_store);
1136 
1137 static ssize_t f_ss_opts_bulk_buflen_show(struct f_ss_opts *opts, char *page)
1138 {
1139 	int result;
1140 
1141 	mutex_lock(&opts->lock);
1142 	result = sprintf(page, "%u", opts->bulk_buflen);
1143 	mutex_unlock(&opts->lock);
1144 
1145 	return result;
1146 }
1147 
1148 static ssize_t f_ss_opts_bulk_buflen_store(struct f_ss_opts *opts,
1149 					   const char *page, size_t len)
1150 {
1151 	int ret;
1152 	u32 num;
1153 
1154 	mutex_lock(&opts->lock);
1155 	if (opts->refcnt) {
1156 		ret = -EBUSY;
1157 		goto end;
1158 	}
1159 
1160 	ret = kstrtou32(page, 0, &num);
1161 	if (ret)
1162 		goto end;
1163 
1164 	opts->bulk_buflen = num;
1165 	ret = len;
1166 end:
1167 	mutex_unlock(&opts->lock);
1168 	return ret;
1169 }
1170 
1171 static struct f_ss_opts_attribute f_ss_opts_bulk_buflen =
1172 	__CONFIGFS_ATTR(buflen, S_IRUGO | S_IWUSR,
1173 			f_ss_opts_bulk_buflen_show,
1174 			f_ss_opts_bulk_buflen_store);
1175 
1176 static struct configfs_attribute *ss_attrs[] = {
1177 	&f_ss_opts_pattern.attr,
1178 	&f_ss_opts_isoc_interval.attr,
1179 	&f_ss_opts_isoc_maxpacket.attr,
1180 	&f_ss_opts_isoc_mult.attr,
1181 	&f_ss_opts_isoc_maxburst.attr,
1182 	&f_ss_opts_bulk_buflen.attr,
1183 	NULL,
1184 };
1185 
1186 static struct config_item_type ss_func_type = {
1187 	.ct_item_ops    = &ss_item_ops,
1188 	.ct_attrs	= ss_attrs,
1189 	.ct_owner       = THIS_MODULE,
1190 };
1191 
1192 static void source_sink_free_instance(struct usb_function_instance *fi)
1193 {
1194 	struct f_ss_opts *ss_opts;
1195 
1196 	ss_opts = container_of(fi, struct f_ss_opts, func_inst);
1197 	kfree(ss_opts);
1198 }
1199 
1200 static struct usb_function_instance *source_sink_alloc_inst(void)
1201 {
1202 	struct f_ss_opts *ss_opts;
1203 
1204 	ss_opts = kzalloc(sizeof(*ss_opts), GFP_KERNEL);
1205 	if (!ss_opts)
1206 		return ERR_PTR(-ENOMEM);
1207 	mutex_init(&ss_opts->lock);
1208 	ss_opts->func_inst.free_func_inst = source_sink_free_instance;
1209 	ss_opts->isoc_interval = GZERO_ISOC_INTERVAL;
1210 	ss_opts->isoc_maxpacket = GZERO_ISOC_MAXPACKET;
1211 	ss_opts->bulk_buflen = GZERO_BULK_BUFLEN;
1212 
1213 	config_group_init_type_name(&ss_opts->func_inst.group, "",
1214 				    &ss_func_type);
1215 
1216 	return &ss_opts->func_inst;
1217 }
1218 DECLARE_USB_FUNCTION(SourceSink, source_sink_alloc_inst,
1219 		source_sink_alloc_func);
1220 
1221 static int __init sslb_modinit(void)
1222 {
1223 	int ret;
1224 
1225 	ret = usb_function_register(&SourceSinkusb_func);
1226 	if (ret)
1227 		return ret;
1228 	ret = lb_modinit();
1229 	if (ret)
1230 		usb_function_unregister(&SourceSinkusb_func);
1231 	return ret;
1232 }
1233 static void __exit sslb_modexit(void)
1234 {
1235 	usb_function_unregister(&SourceSinkusb_func);
1236 	lb_modexit();
1237 }
1238 module_init(sslb_modinit);
1239 module_exit(sslb_modexit);
1240 
1241 MODULE_LICENSE("GPL");
1242