xref: /linux/drivers/usb/gadget/function/f_sourcesink.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
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 "gadget_chips.h"
24 #include "u_f.h"
25 
26 /*
27  * SOURCE/SINK FUNCTION ... a primary testing vehicle for USB peripheral
28  * controller drivers.
29  *
30  * This just sinks bulk packets OUT to the peripheral and sources them IN
31  * to the host, optionally with specific data patterns for integrity tests.
32  * As such it supports basic functionality and load tests.
33  *
34  * In terms of control messaging, this supports all the standard requests
35  * plus two that support control-OUT tests.  If the optional "autoresume"
36  * mode is enabled, it provides good functional coverage for the "USBCV"
37  * test harness from USB-IF.
38  *
39  * Note that because this doesn't queue more than one request at a time,
40  * some other function must be used to test queueing logic.  The network
41  * link (g_ether) is the best overall option for that, since its TX and RX
42  * queues are relatively independent, will receive a range of packet sizes,
43  * and can often be made to run out completely.  Those issues are important
44  * when stress testing peripheral controller drivers.
45  *
46  *
47  * This is currently packaged as a configuration driver, which can't be
48  * combined with other functions to make composite devices.  However, it
49  * can be combined with other independent configurations.
50  */
51 struct f_sourcesink {
52 	struct usb_function	function;
53 
54 	struct usb_ep		*in_ep;
55 	struct usb_ep		*out_ep;
56 	struct usb_ep		*iso_in_ep;
57 	struct usb_ep		*iso_out_ep;
58 	int			cur_alt;
59 };
60 
61 static inline struct f_sourcesink *func_to_ss(struct usb_function *f)
62 {
63 	return container_of(f, struct f_sourcesink, function);
64 }
65 
66 static unsigned pattern;
67 static unsigned isoc_interval;
68 static unsigned isoc_maxpacket;
69 static unsigned isoc_mult;
70 static unsigned isoc_maxburst;
71 static unsigned buflen;
72 
73 /*-------------------------------------------------------------------------*/
74 
75 static struct usb_interface_descriptor source_sink_intf_alt0 = {
76 	.bLength =		USB_DT_INTERFACE_SIZE,
77 	.bDescriptorType =	USB_DT_INTERFACE,
78 
79 	.bAlternateSetting =	0,
80 	.bNumEndpoints =	2,
81 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
82 	/* .iInterface		= DYNAMIC */
83 };
84 
85 static struct usb_interface_descriptor source_sink_intf_alt1 = {
86 	.bLength =		USB_DT_INTERFACE_SIZE,
87 	.bDescriptorType =	USB_DT_INTERFACE,
88 
89 	.bAlternateSetting =	1,
90 	.bNumEndpoints =	4,
91 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
92 	/* .iInterface		= DYNAMIC */
93 };
94 
95 /* full speed support: */
96 
97 static struct usb_endpoint_descriptor fs_source_desc = {
98 	.bLength =		USB_DT_ENDPOINT_SIZE,
99 	.bDescriptorType =	USB_DT_ENDPOINT,
100 
101 	.bEndpointAddress =	USB_DIR_IN,
102 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
103 };
104 
105 static struct usb_endpoint_descriptor fs_sink_desc = {
106 	.bLength =		USB_DT_ENDPOINT_SIZE,
107 	.bDescriptorType =	USB_DT_ENDPOINT,
108 
109 	.bEndpointAddress =	USB_DIR_OUT,
110 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
111 };
112 
113 static struct usb_endpoint_descriptor fs_iso_source_desc = {
114 	.bLength =		USB_DT_ENDPOINT_SIZE,
115 	.bDescriptorType =	USB_DT_ENDPOINT,
116 
117 	.bEndpointAddress =	USB_DIR_IN,
118 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
119 	.wMaxPacketSize =	cpu_to_le16(1023),
120 	.bInterval =		4,
121 };
122 
123 static struct usb_endpoint_descriptor fs_iso_sink_desc = {
124 	.bLength =		USB_DT_ENDPOINT_SIZE,
125 	.bDescriptorType =	USB_DT_ENDPOINT,
126 
127 	.bEndpointAddress =	USB_DIR_OUT,
128 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
129 	.wMaxPacketSize =	cpu_to_le16(1023),
130 	.bInterval =		4,
131 };
132 
133 static struct usb_descriptor_header *fs_source_sink_descs[] = {
134 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
135 	(struct usb_descriptor_header *) &fs_sink_desc,
136 	(struct usb_descriptor_header *) &fs_source_desc,
137 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
138 #define FS_ALT_IFC_1_OFFSET	3
139 	(struct usb_descriptor_header *) &fs_sink_desc,
140 	(struct usb_descriptor_header *) &fs_source_desc,
141 	(struct usb_descriptor_header *) &fs_iso_sink_desc,
142 	(struct usb_descriptor_header *) &fs_iso_source_desc,
143 	NULL,
144 };
145 
146 /* high speed support: */
147 
148 static struct usb_endpoint_descriptor hs_source_desc = {
149 	.bLength =		USB_DT_ENDPOINT_SIZE,
150 	.bDescriptorType =	USB_DT_ENDPOINT,
151 
152 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
153 	.wMaxPacketSize =	cpu_to_le16(512),
154 };
155 
156 static struct usb_endpoint_descriptor hs_sink_desc = {
157 	.bLength =		USB_DT_ENDPOINT_SIZE,
158 	.bDescriptorType =	USB_DT_ENDPOINT,
159 
160 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
161 	.wMaxPacketSize =	cpu_to_le16(512),
162 };
163 
164 static struct usb_endpoint_descriptor hs_iso_source_desc = {
165 	.bLength =		USB_DT_ENDPOINT_SIZE,
166 	.bDescriptorType =	USB_DT_ENDPOINT,
167 
168 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
169 	.wMaxPacketSize =	cpu_to_le16(1024),
170 	.bInterval =		4,
171 };
172 
173 static struct usb_endpoint_descriptor hs_iso_sink_desc = {
174 	.bLength =		USB_DT_ENDPOINT_SIZE,
175 	.bDescriptorType =	USB_DT_ENDPOINT,
176 
177 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
178 	.wMaxPacketSize =	cpu_to_le16(1024),
179 	.bInterval =		4,
180 };
181 
182 static struct usb_descriptor_header *hs_source_sink_descs[] = {
183 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
184 	(struct usb_descriptor_header *) &hs_source_desc,
185 	(struct usb_descriptor_header *) &hs_sink_desc,
186 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
187 #define HS_ALT_IFC_1_OFFSET	3
188 	(struct usb_descriptor_header *) &hs_source_desc,
189 	(struct usb_descriptor_header *) &hs_sink_desc,
190 	(struct usb_descriptor_header *) &hs_iso_source_desc,
191 	(struct usb_descriptor_header *) &hs_iso_sink_desc,
192 	NULL,
193 };
194 
195 /* super speed support: */
196 
197 static struct usb_endpoint_descriptor ss_source_desc = {
198 	.bLength =		USB_DT_ENDPOINT_SIZE,
199 	.bDescriptorType =	USB_DT_ENDPOINT,
200 
201 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
202 	.wMaxPacketSize =	cpu_to_le16(1024),
203 };
204 
205 static struct usb_ss_ep_comp_descriptor ss_source_comp_desc = {
206 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
207 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
208 
209 	.bMaxBurst =		0,
210 	.bmAttributes =		0,
211 	.wBytesPerInterval =	0,
212 };
213 
214 static struct usb_endpoint_descriptor ss_sink_desc = {
215 	.bLength =		USB_DT_ENDPOINT_SIZE,
216 	.bDescriptorType =	USB_DT_ENDPOINT,
217 
218 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
219 	.wMaxPacketSize =	cpu_to_le16(1024),
220 };
221 
222 static struct usb_ss_ep_comp_descriptor ss_sink_comp_desc = {
223 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
224 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
225 
226 	.bMaxBurst =		0,
227 	.bmAttributes =		0,
228 	.wBytesPerInterval =	0,
229 };
230 
231 static struct usb_endpoint_descriptor ss_iso_source_desc = {
232 	.bLength =		USB_DT_ENDPOINT_SIZE,
233 	.bDescriptorType =	USB_DT_ENDPOINT,
234 
235 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
236 	.wMaxPacketSize =	cpu_to_le16(1024),
237 	.bInterval =		4,
238 };
239 
240 static struct usb_ss_ep_comp_descriptor ss_iso_source_comp_desc = {
241 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
242 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
243 
244 	.bMaxBurst =		0,
245 	.bmAttributes =		0,
246 	.wBytesPerInterval =	cpu_to_le16(1024),
247 };
248 
249 static struct usb_endpoint_descriptor ss_iso_sink_desc = {
250 	.bLength =		USB_DT_ENDPOINT_SIZE,
251 	.bDescriptorType =	USB_DT_ENDPOINT,
252 
253 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
254 	.wMaxPacketSize =	cpu_to_le16(1024),
255 	.bInterval =		4,
256 };
257 
258 static struct usb_ss_ep_comp_descriptor ss_iso_sink_comp_desc = {
259 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
260 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
261 
262 	.bMaxBurst =		0,
263 	.bmAttributes =		0,
264 	.wBytesPerInterval =	cpu_to_le16(1024),
265 };
266 
267 static struct usb_descriptor_header *ss_source_sink_descs[] = {
268 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
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 *) &source_sink_intf_alt1,
274 #define SS_ALT_IFC_1_OFFSET	5
275 	(struct usb_descriptor_header *) &ss_source_desc,
276 	(struct usb_descriptor_header *) &ss_source_comp_desc,
277 	(struct usb_descriptor_header *) &ss_sink_desc,
278 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
279 	(struct usb_descriptor_header *) &ss_iso_source_desc,
280 	(struct usb_descriptor_header *) &ss_iso_source_comp_desc,
281 	(struct usb_descriptor_header *) &ss_iso_sink_desc,
282 	(struct usb_descriptor_header *) &ss_iso_sink_comp_desc,
283 	NULL,
284 };
285 
286 /* function-specific strings: */
287 
288 static struct usb_string strings_sourcesink[] = {
289 	[0].s = "source and sink data",
290 	{  }			/* end of list */
291 };
292 
293 static struct usb_gadget_strings stringtab_sourcesink = {
294 	.language	= 0x0409,	/* en-us */
295 	.strings	= strings_sourcesink,
296 };
297 
298 static struct usb_gadget_strings *sourcesink_strings[] = {
299 	&stringtab_sourcesink,
300 	NULL,
301 };
302 
303 /*-------------------------------------------------------------------------*/
304 
305 static inline struct usb_request *ss_alloc_ep_req(struct usb_ep *ep, int len)
306 {
307 	return alloc_ep_req(ep, len, buflen);
308 }
309 
310 void free_ep_req(struct usb_ep *ep, struct usb_request *req)
311 {
312 	kfree(req->buf);
313 	usb_ep_free_request(ep, req);
314 }
315 
316 static void disable_ep(struct usb_composite_dev *cdev, struct usb_ep *ep)
317 {
318 	int			value;
319 
320 	if (ep->driver_data) {
321 		value = usb_ep_disable(ep);
322 		if (value < 0)
323 			DBG(cdev, "disable %s --> %d\n",
324 					ep->name, value);
325 		ep->driver_data = NULL;
326 	}
327 }
328 
329 void disable_endpoints(struct usb_composite_dev *cdev,
330 		struct usb_ep *in, struct usb_ep *out,
331 		struct usb_ep *iso_in, struct usb_ep *iso_out)
332 {
333 	disable_ep(cdev, in);
334 	disable_ep(cdev, out);
335 	if (iso_in)
336 		disable_ep(cdev, iso_in);
337 	if (iso_out)
338 		disable_ep(cdev, iso_out);
339 }
340 
341 static int
342 sourcesink_bind(struct usb_configuration *c, struct usb_function *f)
343 {
344 	struct usb_composite_dev *cdev = c->cdev;
345 	struct f_sourcesink	*ss = func_to_ss(f);
346 	int	id;
347 	int ret;
348 
349 	/* allocate interface ID(s) */
350 	id = usb_interface_id(c, f);
351 	if (id < 0)
352 		return id;
353 	source_sink_intf_alt0.bInterfaceNumber = id;
354 	source_sink_intf_alt1.bInterfaceNumber = id;
355 
356 	/* allocate bulk endpoints */
357 	ss->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_source_desc);
358 	if (!ss->in_ep) {
359 autoconf_fail:
360 		ERROR(cdev, "%s: can't autoconfigure on %s\n",
361 			f->name, cdev->gadget->name);
362 		return -ENODEV;
363 	}
364 	ss->in_ep->driver_data = cdev;	/* claim */
365 
366 	ss->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_sink_desc);
367 	if (!ss->out_ep)
368 		goto autoconf_fail;
369 	ss->out_ep->driver_data = cdev;	/* claim */
370 
371 	/* sanity check the isoc module parameters */
372 	if (isoc_interval < 1)
373 		isoc_interval = 1;
374 	if (isoc_interval > 16)
375 		isoc_interval = 16;
376 	if (isoc_mult > 2)
377 		isoc_mult = 2;
378 	if (isoc_maxburst > 15)
379 		isoc_maxburst = 15;
380 
381 	/* fill in the FS isoc descriptors from the module parameters */
382 	fs_iso_source_desc.wMaxPacketSize = isoc_maxpacket > 1023 ?
383 						1023 : isoc_maxpacket;
384 	fs_iso_source_desc.bInterval = isoc_interval;
385 	fs_iso_sink_desc.wMaxPacketSize = isoc_maxpacket > 1023 ?
386 						1023 : isoc_maxpacket;
387 	fs_iso_sink_desc.bInterval = isoc_interval;
388 
389 	/* allocate iso endpoints */
390 	ss->iso_in_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_source_desc);
391 	if (!ss->iso_in_ep)
392 		goto no_iso;
393 	ss->iso_in_ep->driver_data = cdev;	/* claim */
394 
395 	ss->iso_out_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_sink_desc);
396 	if (ss->iso_out_ep) {
397 		ss->iso_out_ep->driver_data = cdev;	/* claim */
398 	} else {
399 		ss->iso_in_ep->driver_data = NULL;
400 		ss->iso_in_ep = NULL;
401 no_iso:
402 		/*
403 		 * We still want to work even if the UDC doesn't have isoc
404 		 * endpoints, so null out the alt interface that contains
405 		 * them and continue.
406 		 */
407 		fs_source_sink_descs[FS_ALT_IFC_1_OFFSET] = NULL;
408 		hs_source_sink_descs[HS_ALT_IFC_1_OFFSET] = NULL;
409 		ss_source_sink_descs[SS_ALT_IFC_1_OFFSET] = NULL;
410 	}
411 
412 	if (isoc_maxpacket > 1024)
413 		isoc_maxpacket = 1024;
414 
415 	/* support high speed hardware */
416 	hs_source_desc.bEndpointAddress = fs_source_desc.bEndpointAddress;
417 	hs_sink_desc.bEndpointAddress = fs_sink_desc.bEndpointAddress;
418 
419 	/*
420 	 * Fill in the HS isoc descriptors from the module parameters.
421 	 * We assume that the user knows what they are doing and won't
422 	 * give parameters that their UDC doesn't support.
423 	 */
424 	hs_iso_source_desc.wMaxPacketSize = isoc_maxpacket;
425 	hs_iso_source_desc.wMaxPacketSize |= isoc_mult << 11;
426 	hs_iso_source_desc.bInterval = isoc_interval;
427 	hs_iso_source_desc.bEndpointAddress =
428 		fs_iso_source_desc.bEndpointAddress;
429 
430 	hs_iso_sink_desc.wMaxPacketSize = isoc_maxpacket;
431 	hs_iso_sink_desc.wMaxPacketSize |= isoc_mult << 11;
432 	hs_iso_sink_desc.bInterval = isoc_interval;
433 	hs_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
434 
435 	/* support super speed hardware */
436 	ss_source_desc.bEndpointAddress =
437 		fs_source_desc.bEndpointAddress;
438 	ss_sink_desc.bEndpointAddress =
439 		fs_sink_desc.bEndpointAddress;
440 
441 	/*
442 	 * Fill in the SS isoc descriptors from the module parameters.
443 	 * We assume that the user knows what they are doing and won't
444 	 * give parameters that their UDC doesn't support.
445 	 */
446 	ss_iso_source_desc.wMaxPacketSize = isoc_maxpacket;
447 	ss_iso_source_desc.bInterval = isoc_interval;
448 	ss_iso_source_comp_desc.bmAttributes = isoc_mult;
449 	ss_iso_source_comp_desc.bMaxBurst = isoc_maxburst;
450 	ss_iso_source_comp_desc.wBytesPerInterval =
451 		isoc_maxpacket * (isoc_mult + 1) * (isoc_maxburst + 1);
452 	ss_iso_source_desc.bEndpointAddress =
453 		fs_iso_source_desc.bEndpointAddress;
454 
455 	ss_iso_sink_desc.wMaxPacketSize = isoc_maxpacket;
456 	ss_iso_sink_desc.bInterval = isoc_interval;
457 	ss_iso_sink_comp_desc.bmAttributes = isoc_mult;
458 	ss_iso_sink_comp_desc.bMaxBurst = isoc_maxburst;
459 	ss_iso_sink_comp_desc.wBytesPerInterval =
460 		isoc_maxpacket * (isoc_mult + 1) * (isoc_maxburst + 1);
461 	ss_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
462 
463 	ret = usb_assign_descriptors(f, fs_source_sink_descs,
464 			hs_source_sink_descs, ss_source_sink_descs);
465 	if (ret)
466 		return ret;
467 
468 	DBG(cdev, "%s speed %s: IN/%s, OUT/%s, ISO-IN/%s, ISO-OUT/%s\n",
469 	    (gadget_is_superspeed(c->cdev->gadget) ? "super" :
470 	     (gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full")),
471 			f->name, ss->in_ep->name, ss->out_ep->name,
472 			ss->iso_in_ep ? ss->iso_in_ep->name : "<none>",
473 			ss->iso_out_ep ? ss->iso_out_ep->name : "<none>");
474 	return 0;
475 }
476 
477 static void
478 sourcesink_free_func(struct usb_function *f)
479 {
480 	struct f_ss_opts *opts;
481 
482 	opts = container_of(f->fi, struct f_ss_opts, func_inst);
483 
484 	mutex_lock(&opts->lock);
485 	opts->refcnt--;
486 	mutex_unlock(&opts->lock);
487 
488 	usb_free_all_descriptors(f);
489 	kfree(func_to_ss(f));
490 }
491 
492 /* optionally require specific source/sink data patterns  */
493 static int check_read_data(struct f_sourcesink *ss, struct usb_request *req)
494 {
495 	unsigned		i;
496 	u8			*buf = req->buf;
497 	struct usb_composite_dev *cdev = ss->function.config->cdev;
498 
499 	if (pattern == 2)
500 		return 0;
501 
502 	for (i = 0; i < req->actual; i++, buf++) {
503 		switch (pattern) {
504 
505 		/* all-zeroes has no synchronization issues */
506 		case 0:
507 			if (*buf == 0)
508 				continue;
509 			break;
510 
511 		/* "mod63" stays in sync with short-terminated transfers,
512 		 * OR otherwise when host and gadget agree on how large
513 		 * each usb transfer request should be.  Resync is done
514 		 * with set_interface or set_config.  (We *WANT* it to
515 		 * get quickly out of sync if controllers or their drivers
516 		 * stutter for any reason, including buffer duplication...)
517 		 */
518 		case 1:
519 			if (*buf == (u8)(i % 63))
520 				continue;
521 			break;
522 		}
523 		ERROR(cdev, "bad OUT byte, buf[%d] = %d\n", i, *buf);
524 		usb_ep_set_halt(ss->out_ep);
525 		return -EINVAL;
526 	}
527 	return 0;
528 }
529 
530 static void reinit_write_data(struct usb_ep *ep, struct usb_request *req)
531 {
532 	unsigned	i;
533 	u8		*buf = req->buf;
534 
535 	switch (pattern) {
536 	case 0:
537 		memset(req->buf, 0, req->length);
538 		break;
539 	case 1:
540 		for  (i = 0; i < req->length; i++)
541 			*buf++ = (u8) (i % 63);
542 		break;
543 	case 2:
544 		break;
545 	}
546 }
547 
548 static void source_sink_complete(struct usb_ep *ep, struct usb_request *req)
549 {
550 	struct usb_composite_dev	*cdev;
551 	struct f_sourcesink		*ss = ep->driver_data;
552 	int				status = req->status;
553 
554 	/* driver_data will be null if ep has been disabled */
555 	if (!ss)
556 		return;
557 
558 	cdev = ss->function.config->cdev;
559 
560 	switch (status) {
561 
562 	case 0:				/* normal completion? */
563 		if (ep == ss->out_ep) {
564 			check_read_data(ss, req);
565 			if (pattern != 2)
566 				memset(req->buf, 0x55, req->length);
567 		}
568 		break;
569 
570 	/* this endpoint is normally active while we're configured */
571 	case -ECONNABORTED:		/* hardware forced ep reset */
572 	case -ECONNRESET:		/* request dequeued */
573 	case -ESHUTDOWN:		/* disconnect from host */
574 		VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
575 				req->actual, req->length);
576 		if (ep == ss->out_ep)
577 			check_read_data(ss, req);
578 		free_ep_req(ep, req);
579 		return;
580 
581 	case -EOVERFLOW:		/* buffer overrun on read means that
582 					 * we didn't provide a big enough
583 					 * buffer.
584 					 */
585 	default:
586 #if 1
587 		DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
588 				status, req->actual, req->length);
589 #endif
590 	case -EREMOTEIO:		/* short read */
591 		break;
592 	}
593 
594 	status = usb_ep_queue(ep, req, GFP_ATOMIC);
595 	if (status) {
596 		ERROR(cdev, "kill %s:  resubmit %d bytes --> %d\n",
597 				ep->name, req->length, status);
598 		usb_ep_set_halt(ep);
599 		/* FIXME recover later ... somehow */
600 	}
601 }
602 
603 static int source_sink_start_ep(struct f_sourcesink *ss, bool is_in,
604 		bool is_iso, int speed)
605 {
606 	struct usb_ep		*ep;
607 	struct usb_request	*req;
608 	int			i, size, status;
609 
610 	for (i = 0; i < 8; i++) {
611 		if (is_iso) {
612 			switch (speed) {
613 			case USB_SPEED_SUPER:
614 				size = isoc_maxpacket * (isoc_mult + 1) *
615 						(isoc_maxburst + 1);
616 				break;
617 			case USB_SPEED_HIGH:
618 				size = isoc_maxpacket * (isoc_mult + 1);
619 				break;
620 			default:
621 				size = isoc_maxpacket > 1023 ?
622 						1023 : isoc_maxpacket;
623 				break;
624 			}
625 			ep = is_in ? ss->iso_in_ep : ss->iso_out_ep;
626 			req = ss_alloc_ep_req(ep, size);
627 		} else {
628 			ep = is_in ? ss->in_ep : ss->out_ep;
629 			req = ss_alloc_ep_req(ep, 0);
630 		}
631 
632 		if (!req)
633 			return -ENOMEM;
634 
635 		req->complete = source_sink_complete;
636 		if (is_in)
637 			reinit_write_data(ep, req);
638 		else if (pattern != 2)
639 			memset(req->buf, 0x55, req->length);
640 
641 		status = usb_ep_queue(ep, req, GFP_ATOMIC);
642 		if (status) {
643 			struct usb_composite_dev	*cdev;
644 
645 			cdev = ss->function.config->cdev;
646 			ERROR(cdev, "start %s%s %s --> %d\n",
647 			      is_iso ? "ISO-" : "", is_in ? "IN" : "OUT",
648 			      ep->name, status);
649 			free_ep_req(ep, req);
650 		}
651 
652 		if (!is_iso)
653 			break;
654 	}
655 
656 	return status;
657 }
658 
659 static void disable_source_sink(struct f_sourcesink *ss)
660 {
661 	struct usb_composite_dev	*cdev;
662 
663 	cdev = ss->function.config->cdev;
664 	disable_endpoints(cdev, ss->in_ep, ss->out_ep, ss->iso_in_ep,
665 			ss->iso_out_ep);
666 	VDBG(cdev, "%s disabled\n", ss->function.name);
667 }
668 
669 static int
670 enable_source_sink(struct usb_composite_dev *cdev, struct f_sourcesink *ss,
671 		int alt)
672 {
673 	int					result = 0;
674 	int					speed = cdev->gadget->speed;
675 	struct usb_ep				*ep;
676 
677 	/* one bulk endpoint writes (sources) zeroes IN (to the host) */
678 	ep = ss->in_ep;
679 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
680 	if (result)
681 		return result;
682 	result = usb_ep_enable(ep);
683 	if (result < 0)
684 		return result;
685 	ep->driver_data = ss;
686 
687 	result = source_sink_start_ep(ss, true, false, speed);
688 	if (result < 0) {
689 fail:
690 		ep = ss->in_ep;
691 		usb_ep_disable(ep);
692 		ep->driver_data = NULL;
693 		return result;
694 	}
695 
696 	/* one bulk endpoint reads (sinks) anything OUT (from the host) */
697 	ep = ss->out_ep;
698 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
699 	if (result)
700 		goto fail;
701 	result = usb_ep_enable(ep);
702 	if (result < 0)
703 		goto fail;
704 	ep->driver_data = ss;
705 
706 	result = source_sink_start_ep(ss, false, false, speed);
707 	if (result < 0) {
708 fail2:
709 		ep = ss->out_ep;
710 		usb_ep_disable(ep);
711 		ep->driver_data = NULL;
712 		goto fail;
713 	}
714 
715 	if (alt == 0)
716 		goto out;
717 
718 	/* one iso endpoint writes (sources) zeroes IN (to the host) */
719 	ep = ss->iso_in_ep;
720 	if (ep) {
721 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
722 		if (result)
723 			goto fail2;
724 		result = usb_ep_enable(ep);
725 		if (result < 0)
726 			goto fail2;
727 		ep->driver_data = ss;
728 
729 		result = source_sink_start_ep(ss, true, true, speed);
730 		if (result < 0) {
731 fail3:
732 			ep = ss->iso_in_ep;
733 			if (ep) {
734 				usb_ep_disable(ep);
735 				ep->driver_data = NULL;
736 			}
737 			goto fail2;
738 		}
739 	}
740 
741 	/* one iso endpoint reads (sinks) anything OUT (from the host) */
742 	ep = ss->iso_out_ep;
743 	if (ep) {
744 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
745 		if (result)
746 			goto fail3;
747 		result = usb_ep_enable(ep);
748 		if (result < 0)
749 			goto fail3;
750 		ep->driver_data = ss;
751 
752 		result = source_sink_start_ep(ss, false, true, speed);
753 		if (result < 0) {
754 			usb_ep_disable(ep);
755 			ep->driver_data = NULL;
756 			goto fail3;
757 		}
758 	}
759 out:
760 	ss->cur_alt = alt;
761 
762 	DBG(cdev, "%s enabled, alt intf %d\n", ss->function.name, alt);
763 	return result;
764 }
765 
766 static int sourcesink_set_alt(struct usb_function *f,
767 		unsigned intf, unsigned alt)
768 {
769 	struct f_sourcesink		*ss = func_to_ss(f);
770 	struct usb_composite_dev	*cdev = f->config->cdev;
771 
772 	if (ss->in_ep->driver_data)
773 		disable_source_sink(ss);
774 	return enable_source_sink(cdev, ss, alt);
775 }
776 
777 static int sourcesink_get_alt(struct usb_function *f, unsigned intf)
778 {
779 	struct f_sourcesink		*ss = func_to_ss(f);
780 
781 	return ss->cur_alt;
782 }
783 
784 static void sourcesink_disable(struct usb_function *f)
785 {
786 	struct f_sourcesink	*ss = func_to_ss(f);
787 
788 	disable_source_sink(ss);
789 }
790 
791 /*-------------------------------------------------------------------------*/
792 
793 static int sourcesink_setup(struct usb_function *f,
794 		const struct usb_ctrlrequest *ctrl)
795 {
796 	struct usb_configuration        *c = f->config;
797 	struct usb_request	*req = c->cdev->req;
798 	int			value = -EOPNOTSUPP;
799 	u16			w_index = le16_to_cpu(ctrl->wIndex);
800 	u16			w_value = le16_to_cpu(ctrl->wValue);
801 	u16			w_length = le16_to_cpu(ctrl->wLength);
802 
803 	req->length = USB_COMP_EP0_BUFSIZ;
804 
805 	/* composite driver infrastructure handles everything except
806 	 * the two control test requests.
807 	 */
808 	switch (ctrl->bRequest) {
809 
810 	/*
811 	 * These are the same vendor-specific requests supported by
812 	 * Intel's USB 2.0 compliance test devices.  We exceed that
813 	 * device spec by allowing multiple-packet requests.
814 	 *
815 	 * NOTE:  the Control-OUT data stays in req->buf ... better
816 	 * would be copying it into a scratch buffer, so that other
817 	 * requests may safely intervene.
818 	 */
819 	case 0x5b:	/* control WRITE test -- fill the buffer */
820 		if (ctrl->bRequestType != (USB_DIR_OUT|USB_TYPE_VENDOR))
821 			goto unknown;
822 		if (w_value || w_index)
823 			break;
824 		/* just read that many bytes into the buffer */
825 		if (w_length > req->length)
826 			break;
827 		value = w_length;
828 		break;
829 	case 0x5c:	/* control READ test -- return the buffer */
830 		if (ctrl->bRequestType != (USB_DIR_IN|USB_TYPE_VENDOR))
831 			goto unknown;
832 		if (w_value || w_index)
833 			break;
834 		/* expect those bytes are still in the buffer; send back */
835 		if (w_length > req->length)
836 			break;
837 		value = w_length;
838 		break;
839 
840 	default:
841 unknown:
842 		VDBG(c->cdev,
843 			"unknown control req%02x.%02x v%04x i%04x l%d\n",
844 			ctrl->bRequestType, ctrl->bRequest,
845 			w_value, w_index, w_length);
846 	}
847 
848 	/* respond with data transfer or status phase? */
849 	if (value >= 0) {
850 		VDBG(c->cdev, "source/sink req%02x.%02x v%04x i%04x l%d\n",
851 			ctrl->bRequestType, ctrl->bRequest,
852 			w_value, w_index, w_length);
853 		req->zero = 0;
854 		req->length = value;
855 		value = usb_ep_queue(c->cdev->gadget->ep0, req, GFP_ATOMIC);
856 		if (value < 0)
857 			ERROR(c->cdev, "source/sink response, err %d\n",
858 					value);
859 	}
860 
861 	/* device either stalls (value < 0) or reports success */
862 	return value;
863 }
864 
865 static struct usb_function *source_sink_alloc_func(
866 		struct usb_function_instance *fi)
867 {
868 	struct f_sourcesink     *ss;
869 	struct f_ss_opts	*ss_opts;
870 
871 	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
872 	if (!ss)
873 		return NULL;
874 
875 	ss_opts =  container_of(fi, struct f_ss_opts, func_inst);
876 
877 	mutex_lock(&ss_opts->lock);
878 	ss_opts->refcnt++;
879 	mutex_unlock(&ss_opts->lock);
880 
881 	pattern = ss_opts->pattern;
882 	isoc_interval = ss_opts->isoc_interval;
883 	isoc_maxpacket = ss_opts->isoc_maxpacket;
884 	isoc_mult = ss_opts->isoc_mult;
885 	isoc_maxburst = ss_opts->isoc_maxburst;
886 	buflen = ss_opts->bulk_buflen;
887 
888 	ss->function.name = "source/sink";
889 	ss->function.bind = sourcesink_bind;
890 	ss->function.set_alt = sourcesink_set_alt;
891 	ss->function.get_alt = sourcesink_get_alt;
892 	ss->function.disable = sourcesink_disable;
893 	ss->function.setup = sourcesink_setup;
894 	ss->function.strings = sourcesink_strings;
895 
896 	ss->function.free_func = sourcesink_free_func;
897 
898 	return &ss->function;
899 }
900 
901 static inline struct f_ss_opts *to_f_ss_opts(struct config_item *item)
902 {
903 	return container_of(to_config_group(item), struct f_ss_opts,
904 			    func_inst.group);
905 }
906 
907 CONFIGFS_ATTR_STRUCT(f_ss_opts);
908 CONFIGFS_ATTR_OPS(f_ss_opts);
909 
910 static void ss_attr_release(struct config_item *item)
911 {
912 	struct f_ss_opts *ss_opts = to_f_ss_opts(item);
913 
914 	usb_put_function_instance(&ss_opts->func_inst);
915 }
916 
917 static struct configfs_item_operations ss_item_ops = {
918 	.release		= ss_attr_release,
919 	.show_attribute		= f_ss_opts_attr_show,
920 	.store_attribute	= f_ss_opts_attr_store,
921 };
922 
923 static ssize_t f_ss_opts_pattern_show(struct f_ss_opts *opts, char *page)
924 {
925 	int result;
926 
927 	mutex_lock(&opts->lock);
928 	result = sprintf(page, "%u", opts->pattern);
929 	mutex_unlock(&opts->lock);
930 
931 	return result;
932 }
933 
934 static ssize_t f_ss_opts_pattern_store(struct f_ss_opts *opts,
935 				       const char *page, size_t len)
936 {
937 	int ret;
938 	u8 num;
939 
940 	mutex_lock(&opts->lock);
941 	if (opts->refcnt) {
942 		ret = -EBUSY;
943 		goto end;
944 	}
945 
946 	ret = kstrtou8(page, 0, &num);
947 	if (ret)
948 		goto end;
949 
950 	if (num != 0 && num != 1 && num != 2) {
951 		ret = -EINVAL;
952 		goto end;
953 	}
954 
955 	opts->pattern = num;
956 	ret = len;
957 end:
958 	mutex_unlock(&opts->lock);
959 	return ret;
960 }
961 
962 static struct f_ss_opts_attribute f_ss_opts_pattern =
963 	__CONFIGFS_ATTR(pattern, S_IRUGO | S_IWUSR,
964 			f_ss_opts_pattern_show,
965 			f_ss_opts_pattern_store);
966 
967 static ssize_t f_ss_opts_isoc_interval_show(struct f_ss_opts *opts, char *page)
968 {
969 	int result;
970 
971 	mutex_lock(&opts->lock);
972 	result = sprintf(page, "%u", opts->isoc_interval);
973 	mutex_unlock(&opts->lock);
974 
975 	return result;
976 }
977 
978 static ssize_t f_ss_opts_isoc_interval_store(struct f_ss_opts *opts,
979 				       const char *page, size_t len)
980 {
981 	int ret;
982 	u8 num;
983 
984 	mutex_lock(&opts->lock);
985 	if (opts->refcnt) {
986 		ret = -EBUSY;
987 		goto end;
988 	}
989 
990 	ret = kstrtou8(page, 0, &num);
991 	if (ret)
992 		goto end;
993 
994 	if (num > 16) {
995 		ret = -EINVAL;
996 		goto end;
997 	}
998 
999 	opts->isoc_interval = num;
1000 	ret = len;
1001 end:
1002 	mutex_unlock(&opts->lock);
1003 	return ret;
1004 }
1005 
1006 static struct f_ss_opts_attribute f_ss_opts_isoc_interval =
1007 	__CONFIGFS_ATTR(isoc_interval, S_IRUGO | S_IWUSR,
1008 			f_ss_opts_isoc_interval_show,
1009 			f_ss_opts_isoc_interval_store);
1010 
1011 static ssize_t f_ss_opts_isoc_maxpacket_show(struct f_ss_opts *opts, char *page)
1012 {
1013 	int result;
1014 
1015 	mutex_lock(&opts->lock);
1016 	result = sprintf(page, "%u", opts->isoc_maxpacket);
1017 	mutex_unlock(&opts->lock);
1018 
1019 	return result;
1020 }
1021 
1022 static ssize_t f_ss_opts_isoc_maxpacket_store(struct f_ss_opts *opts,
1023 				       const char *page, size_t len)
1024 {
1025 	int ret;
1026 	u16 num;
1027 
1028 	mutex_lock(&opts->lock);
1029 	if (opts->refcnt) {
1030 		ret = -EBUSY;
1031 		goto end;
1032 	}
1033 
1034 	ret = kstrtou16(page, 0, &num);
1035 	if (ret)
1036 		goto end;
1037 
1038 	if (num > 1024) {
1039 		ret = -EINVAL;
1040 		goto end;
1041 	}
1042 
1043 	opts->isoc_maxpacket = num;
1044 	ret = len;
1045 end:
1046 	mutex_unlock(&opts->lock);
1047 	return ret;
1048 }
1049 
1050 static struct f_ss_opts_attribute f_ss_opts_isoc_maxpacket =
1051 	__CONFIGFS_ATTR(isoc_maxpacket, S_IRUGO | S_IWUSR,
1052 			f_ss_opts_isoc_maxpacket_show,
1053 			f_ss_opts_isoc_maxpacket_store);
1054 
1055 static ssize_t f_ss_opts_isoc_mult_show(struct f_ss_opts *opts, char *page)
1056 {
1057 	int result;
1058 
1059 	mutex_lock(&opts->lock);
1060 	result = sprintf(page, "%u", opts->isoc_mult);
1061 	mutex_unlock(&opts->lock);
1062 
1063 	return result;
1064 }
1065 
1066 static ssize_t f_ss_opts_isoc_mult_store(struct f_ss_opts *opts,
1067 				       const char *page, size_t len)
1068 {
1069 	int ret;
1070 	u8 num;
1071 
1072 	mutex_lock(&opts->lock);
1073 	if (opts->refcnt) {
1074 		ret = -EBUSY;
1075 		goto end;
1076 	}
1077 
1078 	ret = kstrtou8(page, 0, &num);
1079 	if (ret)
1080 		goto end;
1081 
1082 	if (num > 2) {
1083 		ret = -EINVAL;
1084 		goto end;
1085 	}
1086 
1087 	opts->isoc_mult = num;
1088 	ret = len;
1089 end:
1090 	mutex_unlock(&opts->lock);
1091 	return ret;
1092 }
1093 
1094 static struct f_ss_opts_attribute f_ss_opts_isoc_mult =
1095 	__CONFIGFS_ATTR(isoc_mult, S_IRUGO | S_IWUSR,
1096 			f_ss_opts_isoc_mult_show,
1097 			f_ss_opts_isoc_mult_store);
1098 
1099 static ssize_t f_ss_opts_isoc_maxburst_show(struct f_ss_opts *opts, char *page)
1100 {
1101 	int result;
1102 
1103 	mutex_lock(&opts->lock);
1104 	result = sprintf(page, "%u", opts->isoc_maxburst);
1105 	mutex_unlock(&opts->lock);
1106 
1107 	return result;
1108 }
1109 
1110 static ssize_t f_ss_opts_isoc_maxburst_store(struct f_ss_opts *opts,
1111 				       const char *page, size_t len)
1112 {
1113 	int ret;
1114 	u8 num;
1115 
1116 	mutex_lock(&opts->lock);
1117 	if (opts->refcnt) {
1118 		ret = -EBUSY;
1119 		goto end;
1120 	}
1121 
1122 	ret = kstrtou8(page, 0, &num);
1123 	if (ret)
1124 		goto end;
1125 
1126 	if (num > 15) {
1127 		ret = -EINVAL;
1128 		goto end;
1129 	}
1130 
1131 	opts->isoc_maxburst = num;
1132 	ret = len;
1133 end:
1134 	mutex_unlock(&opts->lock);
1135 	return ret;
1136 }
1137 
1138 static struct f_ss_opts_attribute f_ss_opts_isoc_maxburst =
1139 	__CONFIGFS_ATTR(isoc_maxburst, S_IRUGO | S_IWUSR,
1140 			f_ss_opts_isoc_maxburst_show,
1141 			f_ss_opts_isoc_maxburst_store);
1142 
1143 static ssize_t f_ss_opts_bulk_buflen_show(struct f_ss_opts *opts, char *page)
1144 {
1145 	int result;
1146 
1147 	mutex_lock(&opts->lock);
1148 	result = sprintf(page, "%u", opts->bulk_buflen);
1149 	mutex_unlock(&opts->lock);
1150 
1151 	return result;
1152 }
1153 
1154 static ssize_t f_ss_opts_bulk_buflen_store(struct f_ss_opts *opts,
1155 					   const char *page, size_t len)
1156 {
1157 	int ret;
1158 	u32 num;
1159 
1160 	mutex_lock(&opts->lock);
1161 	if (opts->refcnt) {
1162 		ret = -EBUSY;
1163 		goto end;
1164 	}
1165 
1166 	ret = kstrtou32(page, 0, &num);
1167 	if (ret)
1168 		goto end;
1169 
1170 	opts->bulk_buflen = num;
1171 	ret = len;
1172 end:
1173 	mutex_unlock(&opts->lock);
1174 	return ret;
1175 }
1176 
1177 static struct f_ss_opts_attribute f_ss_opts_bulk_buflen =
1178 	__CONFIGFS_ATTR(buflen, S_IRUGO | S_IWUSR,
1179 			f_ss_opts_bulk_buflen_show,
1180 			f_ss_opts_bulk_buflen_store);
1181 
1182 static struct configfs_attribute *ss_attrs[] = {
1183 	&f_ss_opts_pattern.attr,
1184 	&f_ss_opts_isoc_interval.attr,
1185 	&f_ss_opts_isoc_maxpacket.attr,
1186 	&f_ss_opts_isoc_mult.attr,
1187 	&f_ss_opts_isoc_maxburst.attr,
1188 	&f_ss_opts_bulk_buflen.attr,
1189 	NULL,
1190 };
1191 
1192 static struct config_item_type ss_func_type = {
1193 	.ct_item_ops    = &ss_item_ops,
1194 	.ct_attrs	= ss_attrs,
1195 	.ct_owner       = THIS_MODULE,
1196 };
1197 
1198 static void source_sink_free_instance(struct usb_function_instance *fi)
1199 {
1200 	struct f_ss_opts *ss_opts;
1201 
1202 	ss_opts = container_of(fi, struct f_ss_opts, func_inst);
1203 	kfree(ss_opts);
1204 }
1205 
1206 static struct usb_function_instance *source_sink_alloc_inst(void)
1207 {
1208 	struct f_ss_opts *ss_opts;
1209 
1210 	ss_opts = kzalloc(sizeof(*ss_opts), GFP_KERNEL);
1211 	if (!ss_opts)
1212 		return ERR_PTR(-ENOMEM);
1213 	mutex_init(&ss_opts->lock);
1214 	ss_opts->func_inst.free_func_inst = source_sink_free_instance;
1215 	ss_opts->isoc_interval = GZERO_ISOC_INTERVAL;
1216 	ss_opts->isoc_maxpacket = GZERO_ISOC_MAXPACKET;
1217 	ss_opts->bulk_buflen = GZERO_BULK_BUFLEN;
1218 
1219 	config_group_init_type_name(&ss_opts->func_inst.group, "",
1220 				    &ss_func_type);
1221 
1222 	return &ss_opts->func_inst;
1223 }
1224 DECLARE_USB_FUNCTION(SourceSink, source_sink_alloc_inst,
1225 		source_sink_alloc_func);
1226 
1227 static int __init sslb_modinit(void)
1228 {
1229 	int ret;
1230 
1231 	ret = usb_function_register(&SourceSinkusb_func);
1232 	if (ret)
1233 		return ret;
1234 	ret = lb_modinit();
1235 	if (ret)
1236 		usb_function_unregister(&SourceSinkusb_func);
1237 	return ret;
1238 }
1239 static void __exit sslb_modexit(void)
1240 {
1241 	usb_function_unregister(&SourceSinkusb_func);
1242 	lb_modexit();
1243 }
1244 module_init(sslb_modinit);
1245 module_exit(sslb_modexit);
1246 
1247 MODULE_LICENSE("GPL");
1248