xref: /linux/drivers/usb/gadget/function/f_sourcesink.c (revision 5fd54ace4721fc5ce2bb5aef6318fcf17f421460)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * f_sourcesink.c - USB peripheral source/sink configuration driver
4  *
5  * Copyright (C) 2003-2008 David Brownell
6  * Copyright (C) 2008 by Nokia Corporation
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 /* #define VERBOSE_DEBUG */
15 
16 #include <linux/slab.h>
17 #include <linux/kernel.h>
18 #include <linux/device.h>
19 #include <linux/module.h>
20 #include <linux/usb/composite.h>
21 #include <linux/err.h>
22 
23 #include "g_zero.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 struct f_sourcesink {
40 	struct usb_function	function;
41 
42 	struct usb_ep		*in_ep;
43 	struct usb_ep		*out_ep;
44 	struct usb_ep		*iso_in_ep;
45 	struct usb_ep		*iso_out_ep;
46 	int			cur_alt;
47 
48 	unsigned pattern;
49 	unsigned isoc_interval;
50 	unsigned isoc_maxpacket;
51 	unsigned isoc_mult;
52 	unsigned isoc_maxburst;
53 	unsigned buflen;
54 	unsigned bulk_qlen;
55 	unsigned iso_qlen;
56 };
57 
58 static inline struct f_sourcesink *func_to_ss(struct usb_function *f)
59 {
60 	return container_of(f, struct f_sourcesink, function);
61 }
62 
63 /*-------------------------------------------------------------------------*/
64 
65 static struct usb_interface_descriptor source_sink_intf_alt0 = {
66 	.bLength =		USB_DT_INTERFACE_SIZE,
67 	.bDescriptorType =	USB_DT_INTERFACE,
68 
69 	.bAlternateSetting =	0,
70 	.bNumEndpoints =	2,
71 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
72 	/* .iInterface		= DYNAMIC */
73 };
74 
75 static struct usb_interface_descriptor source_sink_intf_alt1 = {
76 	.bLength =		USB_DT_INTERFACE_SIZE,
77 	.bDescriptorType =	USB_DT_INTERFACE,
78 
79 	.bAlternateSetting =	1,
80 	.bNumEndpoints =	4,
81 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
82 	/* .iInterface		= DYNAMIC */
83 };
84 
85 /* full speed support: */
86 
87 static struct usb_endpoint_descriptor fs_source_desc = {
88 	.bLength =		USB_DT_ENDPOINT_SIZE,
89 	.bDescriptorType =	USB_DT_ENDPOINT,
90 
91 	.bEndpointAddress =	USB_DIR_IN,
92 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
93 };
94 
95 static struct usb_endpoint_descriptor fs_sink_desc = {
96 	.bLength =		USB_DT_ENDPOINT_SIZE,
97 	.bDescriptorType =	USB_DT_ENDPOINT,
98 
99 	.bEndpointAddress =	USB_DIR_OUT,
100 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
101 };
102 
103 static struct usb_endpoint_descriptor fs_iso_source_desc = {
104 	.bLength =		USB_DT_ENDPOINT_SIZE,
105 	.bDescriptorType =	USB_DT_ENDPOINT,
106 
107 	.bEndpointAddress =	USB_DIR_IN,
108 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
109 	.wMaxPacketSize =	cpu_to_le16(1023),
110 	.bInterval =		4,
111 };
112 
113 static struct usb_endpoint_descriptor fs_iso_sink_desc = {
114 	.bLength =		USB_DT_ENDPOINT_SIZE,
115 	.bDescriptorType =	USB_DT_ENDPOINT,
116 
117 	.bEndpointAddress =	USB_DIR_OUT,
118 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
119 	.wMaxPacketSize =	cpu_to_le16(1023),
120 	.bInterval =		4,
121 };
122 
123 static struct usb_descriptor_header *fs_source_sink_descs[] = {
124 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
125 	(struct usb_descriptor_header *) &fs_sink_desc,
126 	(struct usb_descriptor_header *) &fs_source_desc,
127 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
128 #define FS_ALT_IFC_1_OFFSET	3
129 	(struct usb_descriptor_header *) &fs_sink_desc,
130 	(struct usb_descriptor_header *) &fs_source_desc,
131 	(struct usb_descriptor_header *) &fs_iso_sink_desc,
132 	(struct usb_descriptor_header *) &fs_iso_source_desc,
133 	NULL,
134 };
135 
136 /* high speed support: */
137 
138 static struct usb_endpoint_descriptor hs_source_desc = {
139 	.bLength =		USB_DT_ENDPOINT_SIZE,
140 	.bDescriptorType =	USB_DT_ENDPOINT,
141 
142 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
143 	.wMaxPacketSize =	cpu_to_le16(512),
144 };
145 
146 static struct usb_endpoint_descriptor hs_sink_desc = {
147 	.bLength =		USB_DT_ENDPOINT_SIZE,
148 	.bDescriptorType =	USB_DT_ENDPOINT,
149 
150 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
151 	.wMaxPacketSize =	cpu_to_le16(512),
152 };
153 
154 static struct usb_endpoint_descriptor hs_iso_source_desc = {
155 	.bLength =		USB_DT_ENDPOINT_SIZE,
156 	.bDescriptorType =	USB_DT_ENDPOINT,
157 
158 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
159 	.wMaxPacketSize =	cpu_to_le16(1024),
160 	.bInterval =		4,
161 };
162 
163 static struct usb_endpoint_descriptor hs_iso_sink_desc = {
164 	.bLength =		USB_DT_ENDPOINT_SIZE,
165 	.bDescriptorType =	USB_DT_ENDPOINT,
166 
167 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
168 	.wMaxPacketSize =	cpu_to_le16(1024),
169 	.bInterval =		4,
170 };
171 
172 static struct usb_descriptor_header *hs_source_sink_descs[] = {
173 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
174 	(struct usb_descriptor_header *) &hs_source_desc,
175 	(struct usb_descriptor_header *) &hs_sink_desc,
176 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
177 #define HS_ALT_IFC_1_OFFSET	3
178 	(struct usb_descriptor_header *) &hs_source_desc,
179 	(struct usb_descriptor_header *) &hs_sink_desc,
180 	(struct usb_descriptor_header *) &hs_iso_source_desc,
181 	(struct usb_descriptor_header *) &hs_iso_sink_desc,
182 	NULL,
183 };
184 
185 /* super speed support: */
186 
187 static struct usb_endpoint_descriptor ss_source_desc = {
188 	.bLength =		USB_DT_ENDPOINT_SIZE,
189 	.bDescriptorType =	USB_DT_ENDPOINT,
190 
191 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
192 	.wMaxPacketSize =	cpu_to_le16(1024),
193 };
194 
195 static struct usb_ss_ep_comp_descriptor ss_source_comp_desc = {
196 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
197 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
198 
199 	.bMaxBurst =		0,
200 	.bmAttributes =		0,
201 	.wBytesPerInterval =	0,
202 };
203 
204 static struct usb_endpoint_descriptor ss_sink_desc = {
205 	.bLength =		USB_DT_ENDPOINT_SIZE,
206 	.bDescriptorType =	USB_DT_ENDPOINT,
207 
208 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
209 	.wMaxPacketSize =	cpu_to_le16(1024),
210 };
211 
212 static struct usb_ss_ep_comp_descriptor ss_sink_comp_desc = {
213 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
214 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
215 
216 	.bMaxBurst =		0,
217 	.bmAttributes =		0,
218 	.wBytesPerInterval =	0,
219 };
220 
221 static struct usb_endpoint_descriptor ss_iso_source_desc = {
222 	.bLength =		USB_DT_ENDPOINT_SIZE,
223 	.bDescriptorType =	USB_DT_ENDPOINT,
224 
225 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
226 	.wMaxPacketSize =	cpu_to_le16(1024),
227 	.bInterval =		4,
228 };
229 
230 static struct usb_ss_ep_comp_descriptor ss_iso_source_comp_desc = {
231 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
232 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
233 
234 	.bMaxBurst =		0,
235 	.bmAttributes =		0,
236 	.wBytesPerInterval =	cpu_to_le16(1024),
237 };
238 
239 static struct usb_endpoint_descriptor ss_iso_sink_desc = {
240 	.bLength =		USB_DT_ENDPOINT_SIZE,
241 	.bDescriptorType =	USB_DT_ENDPOINT,
242 
243 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
244 	.wMaxPacketSize =	cpu_to_le16(1024),
245 	.bInterval =		4,
246 };
247 
248 static struct usb_ss_ep_comp_descriptor ss_iso_sink_comp_desc = {
249 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
250 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
251 
252 	.bMaxBurst =		0,
253 	.bmAttributes =		0,
254 	.wBytesPerInterval =	cpu_to_le16(1024),
255 };
256 
257 static struct usb_descriptor_header *ss_source_sink_descs[] = {
258 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
259 	(struct usb_descriptor_header *) &ss_source_desc,
260 	(struct usb_descriptor_header *) &ss_source_comp_desc,
261 	(struct usb_descriptor_header *) &ss_sink_desc,
262 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
263 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
264 #define SS_ALT_IFC_1_OFFSET	5
265 	(struct usb_descriptor_header *) &ss_source_desc,
266 	(struct usb_descriptor_header *) &ss_source_comp_desc,
267 	(struct usb_descriptor_header *) &ss_sink_desc,
268 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
269 	(struct usb_descriptor_header *) &ss_iso_source_desc,
270 	(struct usb_descriptor_header *) &ss_iso_source_comp_desc,
271 	(struct usb_descriptor_header *) &ss_iso_sink_desc,
272 	(struct usb_descriptor_header *) &ss_iso_sink_comp_desc,
273 	NULL,
274 };
275 
276 /* function-specific strings: */
277 
278 static struct usb_string strings_sourcesink[] = {
279 	[0].s = "source and sink data",
280 	{  }			/* end of list */
281 };
282 
283 static struct usb_gadget_strings stringtab_sourcesink = {
284 	.language	= 0x0409,	/* en-us */
285 	.strings	= strings_sourcesink,
286 };
287 
288 static struct usb_gadget_strings *sourcesink_strings[] = {
289 	&stringtab_sourcesink,
290 	NULL,
291 };
292 
293 /*-------------------------------------------------------------------------*/
294 
295 static inline struct usb_request *ss_alloc_ep_req(struct usb_ep *ep, int len)
296 {
297 	return alloc_ep_req(ep, len);
298 }
299 
300 static void disable_ep(struct usb_composite_dev *cdev, struct usb_ep *ep)
301 {
302 	int			value;
303 
304 	value = usb_ep_disable(ep);
305 	if (value < 0)
306 		DBG(cdev, "disable %s --> %d\n", ep->name, value);
307 }
308 
309 void disable_endpoints(struct usb_composite_dev *cdev,
310 		struct usb_ep *in, struct usb_ep *out,
311 		struct usb_ep *iso_in, struct usb_ep *iso_out)
312 {
313 	disable_ep(cdev, in);
314 	disable_ep(cdev, out);
315 	if (iso_in)
316 		disable_ep(cdev, iso_in);
317 	if (iso_out)
318 		disable_ep(cdev, iso_out);
319 }
320 
321 static int
322 sourcesink_bind(struct usb_configuration *c, struct usb_function *f)
323 {
324 	struct usb_composite_dev *cdev = c->cdev;
325 	struct f_sourcesink	*ss = func_to_ss(f);
326 	int	id;
327 	int ret;
328 
329 	/* allocate interface ID(s) */
330 	id = usb_interface_id(c, f);
331 	if (id < 0)
332 		return id;
333 	source_sink_intf_alt0.bInterfaceNumber = id;
334 	source_sink_intf_alt1.bInterfaceNumber = id;
335 
336 	/* allocate bulk endpoints */
337 	ss->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_source_desc);
338 	if (!ss->in_ep) {
339 autoconf_fail:
340 		ERROR(cdev, "%s: can't autoconfigure on %s\n",
341 			f->name, cdev->gadget->name);
342 		return -ENODEV;
343 	}
344 
345 	ss->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_sink_desc);
346 	if (!ss->out_ep)
347 		goto autoconf_fail;
348 
349 	/* sanity check the isoc module parameters */
350 	if (ss->isoc_interval < 1)
351 		ss->isoc_interval = 1;
352 	if (ss->isoc_interval > 16)
353 		ss->isoc_interval = 16;
354 	if (ss->isoc_mult > 2)
355 		ss->isoc_mult = 2;
356 	if (ss->isoc_maxburst > 15)
357 		ss->isoc_maxburst = 15;
358 
359 	/* fill in the FS isoc descriptors from the module parameters */
360 	fs_iso_source_desc.wMaxPacketSize = ss->isoc_maxpacket > 1023 ?
361 						1023 : ss->isoc_maxpacket;
362 	fs_iso_source_desc.bInterval = ss->isoc_interval;
363 	fs_iso_sink_desc.wMaxPacketSize = ss->isoc_maxpacket > 1023 ?
364 						1023 : ss->isoc_maxpacket;
365 	fs_iso_sink_desc.bInterval = ss->isoc_interval;
366 
367 	/* allocate iso endpoints */
368 	ss->iso_in_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_source_desc);
369 	if (!ss->iso_in_ep)
370 		goto no_iso;
371 
372 	ss->iso_out_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_sink_desc);
373 	if (!ss->iso_out_ep) {
374 		usb_ep_autoconfig_release(ss->iso_in_ep);
375 		ss->iso_in_ep = NULL;
376 no_iso:
377 		/*
378 		 * We still want to work even if the UDC doesn't have isoc
379 		 * endpoints, so null out the alt interface that contains
380 		 * them and continue.
381 		 */
382 		fs_source_sink_descs[FS_ALT_IFC_1_OFFSET] = NULL;
383 		hs_source_sink_descs[HS_ALT_IFC_1_OFFSET] = NULL;
384 		ss_source_sink_descs[SS_ALT_IFC_1_OFFSET] = NULL;
385 	}
386 
387 	if (ss->isoc_maxpacket > 1024)
388 		ss->isoc_maxpacket = 1024;
389 
390 	/* support high speed hardware */
391 	hs_source_desc.bEndpointAddress = fs_source_desc.bEndpointAddress;
392 	hs_sink_desc.bEndpointAddress = fs_sink_desc.bEndpointAddress;
393 
394 	/*
395 	 * Fill in the HS isoc descriptors from the module parameters.
396 	 * We assume that the user knows what they are doing and won't
397 	 * give parameters that their UDC doesn't support.
398 	 */
399 	hs_iso_source_desc.wMaxPacketSize = ss->isoc_maxpacket;
400 	hs_iso_source_desc.wMaxPacketSize |= ss->isoc_mult << 11;
401 	hs_iso_source_desc.bInterval = ss->isoc_interval;
402 	hs_iso_source_desc.bEndpointAddress =
403 		fs_iso_source_desc.bEndpointAddress;
404 
405 	hs_iso_sink_desc.wMaxPacketSize = ss->isoc_maxpacket;
406 	hs_iso_sink_desc.wMaxPacketSize |= ss->isoc_mult << 11;
407 	hs_iso_sink_desc.bInterval = ss->isoc_interval;
408 	hs_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
409 
410 	/* support super speed hardware */
411 	ss_source_desc.bEndpointAddress =
412 		fs_source_desc.bEndpointAddress;
413 	ss_sink_desc.bEndpointAddress =
414 		fs_sink_desc.bEndpointAddress;
415 
416 	/*
417 	 * Fill in the SS isoc descriptors from the module parameters.
418 	 * We assume that the user knows what they are doing and won't
419 	 * give parameters that their UDC doesn't support.
420 	 */
421 	ss_iso_source_desc.wMaxPacketSize = ss->isoc_maxpacket;
422 	ss_iso_source_desc.bInterval = ss->isoc_interval;
423 	ss_iso_source_comp_desc.bmAttributes = ss->isoc_mult;
424 	ss_iso_source_comp_desc.bMaxBurst = ss->isoc_maxburst;
425 	ss_iso_source_comp_desc.wBytesPerInterval = ss->isoc_maxpacket *
426 		(ss->isoc_mult + 1) * (ss->isoc_maxburst + 1);
427 	ss_iso_source_desc.bEndpointAddress =
428 		fs_iso_source_desc.bEndpointAddress;
429 
430 	ss_iso_sink_desc.wMaxPacketSize = ss->isoc_maxpacket;
431 	ss_iso_sink_desc.bInterval = ss->isoc_interval;
432 	ss_iso_sink_comp_desc.bmAttributes = ss->isoc_mult;
433 	ss_iso_sink_comp_desc.bMaxBurst = ss->isoc_maxburst;
434 	ss_iso_sink_comp_desc.wBytesPerInterval = ss->isoc_maxpacket *
435 		(ss->isoc_mult + 1) * (ss->isoc_maxburst + 1);
436 	ss_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
437 
438 	ret = usb_assign_descriptors(f, fs_source_sink_descs,
439 			hs_source_sink_descs, ss_source_sink_descs, NULL);
440 	if (ret)
441 		return ret;
442 
443 	DBG(cdev, "%s speed %s: IN/%s, OUT/%s, ISO-IN/%s, ISO-OUT/%s\n",
444 	    (gadget_is_superspeed(c->cdev->gadget) ? "super" :
445 	     (gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full")),
446 			f->name, ss->in_ep->name, ss->out_ep->name,
447 			ss->iso_in_ep ? ss->iso_in_ep->name : "<none>",
448 			ss->iso_out_ep ? ss->iso_out_ep->name : "<none>");
449 	return 0;
450 }
451 
452 static void
453 sourcesink_free_func(struct usb_function *f)
454 {
455 	struct f_ss_opts *opts;
456 
457 	opts = container_of(f->fi, struct f_ss_opts, func_inst);
458 
459 	mutex_lock(&opts->lock);
460 	opts->refcnt--;
461 	mutex_unlock(&opts->lock);
462 
463 	usb_free_all_descriptors(f);
464 	kfree(func_to_ss(f));
465 }
466 
467 /* optionally require specific source/sink data patterns  */
468 static int check_read_data(struct f_sourcesink *ss, struct usb_request *req)
469 {
470 	unsigned		i;
471 	u8			*buf = req->buf;
472 	struct usb_composite_dev *cdev = ss->function.config->cdev;
473 	int max_packet_size = le16_to_cpu(ss->out_ep->desc->wMaxPacketSize);
474 
475 	if (ss->pattern == 2)
476 		return 0;
477 
478 	for (i = 0; i < req->actual; i++, buf++) {
479 		switch (ss->pattern) {
480 
481 		/* all-zeroes has no synchronization issues */
482 		case 0:
483 			if (*buf == 0)
484 				continue;
485 			break;
486 
487 		/* "mod63" stays in sync with short-terminated transfers,
488 		 * OR otherwise when host and gadget agree on how large
489 		 * each usb transfer request should be.  Resync is done
490 		 * with set_interface or set_config.  (We *WANT* it to
491 		 * get quickly out of sync if controllers or their drivers
492 		 * stutter for any reason, including buffer duplication...)
493 		 */
494 		case 1:
495 			if (*buf == (u8)((i % max_packet_size) % 63))
496 				continue;
497 			break;
498 		}
499 		ERROR(cdev, "bad OUT byte, buf[%d] = %d\n", i, *buf);
500 		usb_ep_set_halt(ss->out_ep);
501 		return -EINVAL;
502 	}
503 	return 0;
504 }
505 
506 static void reinit_write_data(struct usb_ep *ep, struct usb_request *req)
507 {
508 	unsigned	i;
509 	u8		*buf = req->buf;
510 	int max_packet_size = le16_to_cpu(ep->desc->wMaxPacketSize);
511 	struct f_sourcesink *ss = ep->driver_data;
512 
513 	switch (ss->pattern) {
514 	case 0:
515 		memset(req->buf, 0, req->length);
516 		break;
517 	case 1:
518 		for  (i = 0; i < req->length; i++)
519 			*buf++ = (u8) ((i % max_packet_size) % 63);
520 		break;
521 	case 2:
522 		break;
523 	}
524 }
525 
526 static void source_sink_complete(struct usb_ep *ep, struct usb_request *req)
527 {
528 	struct usb_composite_dev	*cdev;
529 	struct f_sourcesink		*ss = ep->driver_data;
530 	int				status = req->status;
531 
532 	/* driver_data will be null if ep has been disabled */
533 	if (!ss)
534 		return;
535 
536 	cdev = ss->function.config->cdev;
537 
538 	switch (status) {
539 
540 	case 0:				/* normal completion? */
541 		if (ep == ss->out_ep) {
542 			check_read_data(ss, req);
543 			if (ss->pattern != 2)
544 				memset(req->buf, 0x55, req->length);
545 		}
546 		break;
547 
548 	/* this endpoint is normally active while we're configured */
549 	case -ECONNABORTED:		/* hardware forced ep reset */
550 	case -ECONNRESET:		/* request dequeued */
551 	case -ESHUTDOWN:		/* disconnect from host */
552 		VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
553 				req->actual, req->length);
554 		if (ep == ss->out_ep)
555 			check_read_data(ss, req);
556 		free_ep_req(ep, req);
557 		return;
558 
559 	case -EOVERFLOW:		/* buffer overrun on read means that
560 					 * we didn't provide a big enough
561 					 * buffer.
562 					 */
563 	default:
564 #if 1
565 		DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
566 				status, req->actual, req->length);
567 #endif
568 	case -EREMOTEIO:		/* short read */
569 		break;
570 	}
571 
572 	status = usb_ep_queue(ep, req, GFP_ATOMIC);
573 	if (status) {
574 		ERROR(cdev, "kill %s:  resubmit %d bytes --> %d\n",
575 				ep->name, req->length, status);
576 		usb_ep_set_halt(ep);
577 		/* FIXME recover later ... somehow */
578 	}
579 }
580 
581 static int source_sink_start_ep(struct f_sourcesink *ss, bool is_in,
582 		bool is_iso, int speed)
583 {
584 	struct usb_ep		*ep;
585 	struct usb_request	*req;
586 	int			i, size, qlen, status = 0;
587 
588 	if (is_iso) {
589 		switch (speed) {
590 		case USB_SPEED_SUPER:
591 			size = ss->isoc_maxpacket *
592 					(ss->isoc_mult + 1) *
593 					(ss->isoc_maxburst + 1);
594 			break;
595 		case USB_SPEED_HIGH:
596 			size = ss->isoc_maxpacket * (ss->isoc_mult + 1);
597 			break;
598 		default:
599 			size = ss->isoc_maxpacket > 1023 ?
600 					1023 : ss->isoc_maxpacket;
601 			break;
602 		}
603 		ep = is_in ? ss->iso_in_ep : ss->iso_out_ep;
604 		qlen = ss->iso_qlen;
605 	} else {
606 		ep = is_in ? ss->in_ep : ss->out_ep;
607 		qlen = ss->bulk_qlen;
608 		size = ss->buflen;
609 	}
610 
611 	for (i = 0; i < qlen; i++) {
612 		req = ss_alloc_ep_req(ep, size);
613 		if (!req)
614 			return -ENOMEM;
615 
616 		req->complete = source_sink_complete;
617 		if (is_in)
618 			reinit_write_data(ep, req);
619 		else if (ss->pattern != 2)
620 			memset(req->buf, 0x55, req->length);
621 
622 		status = usb_ep_queue(ep, req, GFP_ATOMIC);
623 		if (status) {
624 			struct usb_composite_dev	*cdev;
625 
626 			cdev = ss->function.config->cdev;
627 			ERROR(cdev, "start %s%s %s --> %d\n",
628 			      is_iso ? "ISO-" : "", is_in ? "IN" : "OUT",
629 			      ep->name, status);
630 			free_ep_req(ep, req);
631 			return status;
632 		}
633 	}
634 
635 	return status;
636 }
637 
638 static void disable_source_sink(struct f_sourcesink *ss)
639 {
640 	struct usb_composite_dev	*cdev;
641 
642 	cdev = ss->function.config->cdev;
643 	disable_endpoints(cdev, ss->in_ep, ss->out_ep, ss->iso_in_ep,
644 			ss->iso_out_ep);
645 	VDBG(cdev, "%s disabled\n", ss->function.name);
646 }
647 
648 static int
649 enable_source_sink(struct usb_composite_dev *cdev, struct f_sourcesink *ss,
650 		int alt)
651 {
652 	int					result = 0;
653 	int					speed = cdev->gadget->speed;
654 	struct usb_ep				*ep;
655 
656 	/* one bulk endpoint writes (sources) zeroes IN (to the host) */
657 	ep = ss->in_ep;
658 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
659 	if (result)
660 		return result;
661 	result = usb_ep_enable(ep);
662 	if (result < 0)
663 		return result;
664 	ep->driver_data = ss;
665 
666 	result = source_sink_start_ep(ss, true, false, speed);
667 	if (result < 0) {
668 fail:
669 		ep = ss->in_ep;
670 		usb_ep_disable(ep);
671 		return result;
672 	}
673 
674 	/* one bulk endpoint reads (sinks) anything OUT (from the host) */
675 	ep = ss->out_ep;
676 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
677 	if (result)
678 		goto fail;
679 	result = usb_ep_enable(ep);
680 	if (result < 0)
681 		goto fail;
682 	ep->driver_data = ss;
683 
684 	result = source_sink_start_ep(ss, false, false, speed);
685 	if (result < 0) {
686 fail2:
687 		ep = ss->out_ep;
688 		usb_ep_disable(ep);
689 		goto fail;
690 	}
691 
692 	if (alt == 0)
693 		goto out;
694 
695 	/* one iso endpoint writes (sources) zeroes IN (to the host) */
696 	ep = ss->iso_in_ep;
697 	if (ep) {
698 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
699 		if (result)
700 			goto fail2;
701 		result = usb_ep_enable(ep);
702 		if (result < 0)
703 			goto fail2;
704 		ep->driver_data = ss;
705 
706 		result = source_sink_start_ep(ss, true, true, speed);
707 		if (result < 0) {
708 fail3:
709 			ep = ss->iso_in_ep;
710 			if (ep)
711 				usb_ep_disable(ep);
712 			goto fail2;
713 		}
714 	}
715 
716 	/* one iso endpoint reads (sinks) anything OUT (from the host) */
717 	ep = ss->iso_out_ep;
718 	if (ep) {
719 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
720 		if (result)
721 			goto fail3;
722 		result = usb_ep_enable(ep);
723 		if (result < 0)
724 			goto fail3;
725 		ep->driver_data = ss;
726 
727 		result = source_sink_start_ep(ss, false, true, speed);
728 		if (result < 0) {
729 			usb_ep_disable(ep);
730 			goto fail3;
731 		}
732 	}
733 out:
734 	ss->cur_alt = alt;
735 
736 	DBG(cdev, "%s enabled, alt intf %d\n", ss->function.name, alt);
737 	return result;
738 }
739 
740 static int sourcesink_set_alt(struct usb_function *f,
741 		unsigned intf, unsigned alt)
742 {
743 	struct f_sourcesink		*ss = func_to_ss(f);
744 	struct usb_composite_dev	*cdev = f->config->cdev;
745 
746 	disable_source_sink(ss);
747 	return enable_source_sink(cdev, ss, alt);
748 }
749 
750 static int sourcesink_get_alt(struct usb_function *f, unsigned intf)
751 {
752 	struct f_sourcesink		*ss = func_to_ss(f);
753 
754 	return ss->cur_alt;
755 }
756 
757 static void sourcesink_disable(struct usb_function *f)
758 {
759 	struct f_sourcesink	*ss = func_to_ss(f);
760 
761 	disable_source_sink(ss);
762 }
763 
764 /*-------------------------------------------------------------------------*/
765 
766 static int sourcesink_setup(struct usb_function *f,
767 		const struct usb_ctrlrequest *ctrl)
768 {
769 	struct usb_configuration        *c = f->config;
770 	struct usb_request	*req = c->cdev->req;
771 	int			value = -EOPNOTSUPP;
772 	u16			w_index = le16_to_cpu(ctrl->wIndex);
773 	u16			w_value = le16_to_cpu(ctrl->wValue);
774 	u16			w_length = le16_to_cpu(ctrl->wLength);
775 
776 	req->length = USB_COMP_EP0_BUFSIZ;
777 
778 	/* composite driver infrastructure handles everything except
779 	 * the two control test requests.
780 	 */
781 	switch (ctrl->bRequest) {
782 
783 	/*
784 	 * These are the same vendor-specific requests supported by
785 	 * Intel's USB 2.0 compliance test devices.  We exceed that
786 	 * device spec by allowing multiple-packet requests.
787 	 *
788 	 * NOTE:  the Control-OUT data stays in req->buf ... better
789 	 * would be copying it into a scratch buffer, so that other
790 	 * requests may safely intervene.
791 	 */
792 	case 0x5b:	/* control WRITE test -- fill the buffer */
793 		if (ctrl->bRequestType != (USB_DIR_OUT|USB_TYPE_VENDOR))
794 			goto unknown;
795 		if (w_value || w_index)
796 			break;
797 		/* just read that many bytes into the buffer */
798 		if (w_length > req->length)
799 			break;
800 		value = w_length;
801 		break;
802 	case 0x5c:	/* control READ test -- return the buffer */
803 		if (ctrl->bRequestType != (USB_DIR_IN|USB_TYPE_VENDOR))
804 			goto unknown;
805 		if (w_value || w_index)
806 			break;
807 		/* expect those bytes are still in the buffer; send back */
808 		if (w_length > req->length)
809 			break;
810 		value = w_length;
811 		break;
812 
813 	default:
814 unknown:
815 		VDBG(c->cdev,
816 			"unknown control req%02x.%02x v%04x i%04x l%d\n",
817 			ctrl->bRequestType, ctrl->bRequest,
818 			w_value, w_index, w_length);
819 	}
820 
821 	/* respond with data transfer or status phase? */
822 	if (value >= 0) {
823 		VDBG(c->cdev, "source/sink req%02x.%02x v%04x i%04x l%d\n",
824 			ctrl->bRequestType, ctrl->bRequest,
825 			w_value, w_index, w_length);
826 		req->zero = 0;
827 		req->length = value;
828 		value = usb_ep_queue(c->cdev->gadget->ep0, req, GFP_ATOMIC);
829 		if (value < 0)
830 			ERROR(c->cdev, "source/sink response, err %d\n",
831 					value);
832 	}
833 
834 	/* device either stalls (value < 0) or reports success */
835 	return value;
836 }
837 
838 static struct usb_function *source_sink_alloc_func(
839 		struct usb_function_instance *fi)
840 {
841 	struct f_sourcesink     *ss;
842 	struct f_ss_opts	*ss_opts;
843 
844 	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
845 	if (!ss)
846 		return NULL;
847 
848 	ss_opts =  container_of(fi, struct f_ss_opts, func_inst);
849 
850 	mutex_lock(&ss_opts->lock);
851 	ss_opts->refcnt++;
852 	mutex_unlock(&ss_opts->lock);
853 
854 	ss->pattern = ss_opts->pattern;
855 	ss->isoc_interval = ss_opts->isoc_interval;
856 	ss->isoc_maxpacket = ss_opts->isoc_maxpacket;
857 	ss->isoc_mult = ss_opts->isoc_mult;
858 	ss->isoc_maxburst = ss_opts->isoc_maxburst;
859 	ss->buflen = ss_opts->bulk_buflen;
860 	ss->bulk_qlen = ss_opts->bulk_qlen;
861 	ss->iso_qlen = ss_opts->iso_qlen;
862 
863 	ss->function.name = "source/sink";
864 	ss->function.bind = sourcesink_bind;
865 	ss->function.set_alt = sourcesink_set_alt;
866 	ss->function.get_alt = sourcesink_get_alt;
867 	ss->function.disable = sourcesink_disable;
868 	ss->function.setup = sourcesink_setup;
869 	ss->function.strings = sourcesink_strings;
870 
871 	ss->function.free_func = sourcesink_free_func;
872 
873 	return &ss->function;
874 }
875 
876 static inline struct f_ss_opts *to_f_ss_opts(struct config_item *item)
877 {
878 	return container_of(to_config_group(item), struct f_ss_opts,
879 			    func_inst.group);
880 }
881 
882 static void ss_attr_release(struct config_item *item)
883 {
884 	struct f_ss_opts *ss_opts = to_f_ss_opts(item);
885 
886 	usb_put_function_instance(&ss_opts->func_inst);
887 }
888 
889 static struct configfs_item_operations ss_item_ops = {
890 	.release		= ss_attr_release,
891 };
892 
893 static ssize_t f_ss_opts_pattern_show(struct config_item *item, char *page)
894 {
895 	struct f_ss_opts *opts = to_f_ss_opts(item);
896 	int result;
897 
898 	mutex_lock(&opts->lock);
899 	result = sprintf(page, "%u\n", opts->pattern);
900 	mutex_unlock(&opts->lock);
901 
902 	return result;
903 }
904 
905 static ssize_t f_ss_opts_pattern_store(struct config_item *item,
906 				       const char *page, size_t len)
907 {
908 	struct f_ss_opts *opts = to_f_ss_opts(item);
909 	int ret;
910 	u8 num;
911 
912 	mutex_lock(&opts->lock);
913 	if (opts->refcnt) {
914 		ret = -EBUSY;
915 		goto end;
916 	}
917 
918 	ret = kstrtou8(page, 0, &num);
919 	if (ret)
920 		goto end;
921 
922 	if (num != 0 && num != 1 && num != 2) {
923 		ret = -EINVAL;
924 		goto end;
925 	}
926 
927 	opts->pattern = num;
928 	ret = len;
929 end:
930 	mutex_unlock(&opts->lock);
931 	return ret;
932 }
933 
934 CONFIGFS_ATTR(f_ss_opts_, pattern);
935 
936 static ssize_t f_ss_opts_isoc_interval_show(struct config_item *item, char *page)
937 {
938 	struct f_ss_opts *opts = to_f_ss_opts(item);
939 	int result;
940 
941 	mutex_lock(&opts->lock);
942 	result = sprintf(page, "%u\n", opts->isoc_interval);
943 	mutex_unlock(&opts->lock);
944 
945 	return result;
946 }
947 
948 static ssize_t f_ss_opts_isoc_interval_store(struct config_item *item,
949 				       const char *page, size_t len)
950 {
951 	struct f_ss_opts *opts = to_f_ss_opts(item);
952 	int ret;
953 	u8 num;
954 
955 	mutex_lock(&opts->lock);
956 	if (opts->refcnt) {
957 		ret = -EBUSY;
958 		goto end;
959 	}
960 
961 	ret = kstrtou8(page, 0, &num);
962 	if (ret)
963 		goto end;
964 
965 	if (num > 16) {
966 		ret = -EINVAL;
967 		goto end;
968 	}
969 
970 	opts->isoc_interval = num;
971 	ret = len;
972 end:
973 	mutex_unlock(&opts->lock);
974 	return ret;
975 }
976 
977 CONFIGFS_ATTR(f_ss_opts_, isoc_interval);
978 
979 static ssize_t f_ss_opts_isoc_maxpacket_show(struct config_item *item, char *page)
980 {
981 	struct f_ss_opts *opts = to_f_ss_opts(item);
982 	int result;
983 
984 	mutex_lock(&opts->lock);
985 	result = sprintf(page, "%u\n", opts->isoc_maxpacket);
986 	mutex_unlock(&opts->lock);
987 
988 	return result;
989 }
990 
991 static ssize_t f_ss_opts_isoc_maxpacket_store(struct config_item *item,
992 				       const char *page, size_t len)
993 {
994 	struct f_ss_opts *opts = to_f_ss_opts(item);
995 	int ret;
996 	u16 num;
997 
998 	mutex_lock(&opts->lock);
999 	if (opts->refcnt) {
1000 		ret = -EBUSY;
1001 		goto end;
1002 	}
1003 
1004 	ret = kstrtou16(page, 0, &num);
1005 	if (ret)
1006 		goto end;
1007 
1008 	if (num > 1024) {
1009 		ret = -EINVAL;
1010 		goto end;
1011 	}
1012 
1013 	opts->isoc_maxpacket = num;
1014 	ret = len;
1015 end:
1016 	mutex_unlock(&opts->lock);
1017 	return ret;
1018 }
1019 
1020 CONFIGFS_ATTR(f_ss_opts_, isoc_maxpacket);
1021 
1022 static ssize_t f_ss_opts_isoc_mult_show(struct config_item *item, char *page)
1023 {
1024 	struct f_ss_opts *opts = to_f_ss_opts(item);
1025 	int result;
1026 
1027 	mutex_lock(&opts->lock);
1028 	result = sprintf(page, "%u\n", opts->isoc_mult);
1029 	mutex_unlock(&opts->lock);
1030 
1031 	return result;
1032 }
1033 
1034 static ssize_t f_ss_opts_isoc_mult_store(struct config_item *item,
1035 				       const char *page, size_t len)
1036 {
1037 	struct f_ss_opts *opts = to_f_ss_opts(item);
1038 	int ret;
1039 	u8 num;
1040 
1041 	mutex_lock(&opts->lock);
1042 	if (opts->refcnt) {
1043 		ret = -EBUSY;
1044 		goto end;
1045 	}
1046 
1047 	ret = kstrtou8(page, 0, &num);
1048 	if (ret)
1049 		goto end;
1050 
1051 	if (num > 2) {
1052 		ret = -EINVAL;
1053 		goto end;
1054 	}
1055 
1056 	opts->isoc_mult = num;
1057 	ret = len;
1058 end:
1059 	mutex_unlock(&opts->lock);
1060 	return ret;
1061 }
1062 
1063 CONFIGFS_ATTR(f_ss_opts_, isoc_mult);
1064 
1065 static ssize_t f_ss_opts_isoc_maxburst_show(struct config_item *item, char *page)
1066 {
1067 	struct f_ss_opts *opts = to_f_ss_opts(item);
1068 	int result;
1069 
1070 	mutex_lock(&opts->lock);
1071 	result = sprintf(page, "%u\n", opts->isoc_maxburst);
1072 	mutex_unlock(&opts->lock);
1073 
1074 	return result;
1075 }
1076 
1077 static ssize_t f_ss_opts_isoc_maxburst_store(struct config_item *item,
1078 				       const char *page, size_t len)
1079 {
1080 	struct f_ss_opts *opts = to_f_ss_opts(item);
1081 	int ret;
1082 	u8 num;
1083 
1084 	mutex_lock(&opts->lock);
1085 	if (opts->refcnt) {
1086 		ret = -EBUSY;
1087 		goto end;
1088 	}
1089 
1090 	ret = kstrtou8(page, 0, &num);
1091 	if (ret)
1092 		goto end;
1093 
1094 	if (num > 15) {
1095 		ret = -EINVAL;
1096 		goto end;
1097 	}
1098 
1099 	opts->isoc_maxburst = num;
1100 	ret = len;
1101 end:
1102 	mutex_unlock(&opts->lock);
1103 	return ret;
1104 }
1105 
1106 CONFIGFS_ATTR(f_ss_opts_, isoc_maxburst);
1107 
1108 static ssize_t f_ss_opts_bulk_buflen_show(struct config_item *item, char *page)
1109 {
1110 	struct f_ss_opts *opts = to_f_ss_opts(item);
1111 	int result;
1112 
1113 	mutex_lock(&opts->lock);
1114 	result = sprintf(page, "%u\n", opts->bulk_buflen);
1115 	mutex_unlock(&opts->lock);
1116 
1117 	return result;
1118 }
1119 
1120 static ssize_t f_ss_opts_bulk_buflen_store(struct config_item *item,
1121 					   const char *page, size_t len)
1122 {
1123 	struct f_ss_opts *opts = to_f_ss_opts(item);
1124 	int ret;
1125 	u32 num;
1126 
1127 	mutex_lock(&opts->lock);
1128 	if (opts->refcnt) {
1129 		ret = -EBUSY;
1130 		goto end;
1131 	}
1132 
1133 	ret = kstrtou32(page, 0, &num);
1134 	if (ret)
1135 		goto end;
1136 
1137 	opts->bulk_buflen = num;
1138 	ret = len;
1139 end:
1140 	mutex_unlock(&opts->lock);
1141 	return ret;
1142 }
1143 
1144 CONFIGFS_ATTR(f_ss_opts_, bulk_buflen);
1145 
1146 static ssize_t f_ss_opts_bulk_qlen_show(struct config_item *item, char *page)
1147 {
1148 	struct f_ss_opts *opts = to_f_ss_opts(item);
1149 	int result;
1150 
1151 	mutex_lock(&opts->lock);
1152 	result = sprintf(page, "%u\n", opts->bulk_qlen);
1153 	mutex_unlock(&opts->lock);
1154 
1155 	return result;
1156 }
1157 
1158 static ssize_t f_ss_opts_bulk_qlen_store(struct config_item *item,
1159 					   const char *page, size_t len)
1160 {
1161 	struct f_ss_opts *opts = to_f_ss_opts(item);
1162 	int ret;
1163 	u32 num;
1164 
1165 	mutex_lock(&opts->lock);
1166 	if (opts->refcnt) {
1167 		ret = -EBUSY;
1168 		goto end;
1169 	}
1170 
1171 	ret = kstrtou32(page, 0, &num);
1172 	if (ret)
1173 		goto end;
1174 
1175 	opts->bulk_qlen = num;
1176 	ret = len;
1177 end:
1178 	mutex_unlock(&opts->lock);
1179 	return ret;
1180 }
1181 
1182 CONFIGFS_ATTR(f_ss_opts_, bulk_qlen);
1183 
1184 static ssize_t f_ss_opts_iso_qlen_show(struct config_item *item, char *page)
1185 {
1186 	struct f_ss_opts *opts = to_f_ss_opts(item);
1187 	int result;
1188 
1189 	mutex_lock(&opts->lock);
1190 	result = sprintf(page, "%u\n", opts->iso_qlen);
1191 	mutex_unlock(&opts->lock);
1192 
1193 	return result;
1194 }
1195 
1196 static ssize_t f_ss_opts_iso_qlen_store(struct config_item *item,
1197 					   const char *page, size_t len)
1198 {
1199 	struct f_ss_opts *opts = to_f_ss_opts(item);
1200 	int ret;
1201 	u32 num;
1202 
1203 	mutex_lock(&opts->lock);
1204 	if (opts->refcnt) {
1205 		ret = -EBUSY;
1206 		goto end;
1207 	}
1208 
1209 	ret = kstrtou32(page, 0, &num);
1210 	if (ret)
1211 		goto end;
1212 
1213 	opts->iso_qlen = num;
1214 	ret = len;
1215 end:
1216 	mutex_unlock(&opts->lock);
1217 	return ret;
1218 }
1219 
1220 CONFIGFS_ATTR(f_ss_opts_, iso_qlen);
1221 
1222 static struct configfs_attribute *ss_attrs[] = {
1223 	&f_ss_opts_attr_pattern,
1224 	&f_ss_opts_attr_isoc_interval,
1225 	&f_ss_opts_attr_isoc_maxpacket,
1226 	&f_ss_opts_attr_isoc_mult,
1227 	&f_ss_opts_attr_isoc_maxburst,
1228 	&f_ss_opts_attr_bulk_buflen,
1229 	&f_ss_opts_attr_bulk_qlen,
1230 	&f_ss_opts_attr_iso_qlen,
1231 	NULL,
1232 };
1233 
1234 static struct config_item_type ss_func_type = {
1235 	.ct_item_ops    = &ss_item_ops,
1236 	.ct_attrs	= ss_attrs,
1237 	.ct_owner       = THIS_MODULE,
1238 };
1239 
1240 static void source_sink_free_instance(struct usb_function_instance *fi)
1241 {
1242 	struct f_ss_opts *ss_opts;
1243 
1244 	ss_opts = container_of(fi, struct f_ss_opts, func_inst);
1245 	kfree(ss_opts);
1246 }
1247 
1248 static struct usb_function_instance *source_sink_alloc_inst(void)
1249 {
1250 	struct f_ss_opts *ss_opts;
1251 
1252 	ss_opts = kzalloc(sizeof(*ss_opts), GFP_KERNEL);
1253 	if (!ss_opts)
1254 		return ERR_PTR(-ENOMEM);
1255 	mutex_init(&ss_opts->lock);
1256 	ss_opts->func_inst.free_func_inst = source_sink_free_instance;
1257 	ss_opts->isoc_interval = GZERO_ISOC_INTERVAL;
1258 	ss_opts->isoc_maxpacket = GZERO_ISOC_MAXPACKET;
1259 	ss_opts->bulk_buflen = GZERO_BULK_BUFLEN;
1260 	ss_opts->bulk_qlen = GZERO_SS_BULK_QLEN;
1261 	ss_opts->iso_qlen = GZERO_SS_ISO_QLEN;
1262 
1263 	config_group_init_type_name(&ss_opts->func_inst.group, "",
1264 				    &ss_func_type);
1265 
1266 	return &ss_opts->func_inst;
1267 }
1268 DECLARE_USB_FUNCTION(SourceSink, source_sink_alloc_inst,
1269 		source_sink_alloc_func);
1270 
1271 static int __init sslb_modinit(void)
1272 {
1273 	int ret;
1274 
1275 	ret = usb_function_register(&SourceSinkusb_func);
1276 	if (ret)
1277 		return ret;
1278 	ret = lb_modinit();
1279 	if (ret)
1280 		usb_function_unregister(&SourceSinkusb_func);
1281 	return ret;
1282 }
1283 static void __exit sslb_modexit(void)
1284 {
1285 	usb_function_unregister(&SourceSinkusb_func);
1286 	lb_modexit();
1287 }
1288 module_init(sslb_modinit);
1289 module_exit(sslb_modexit);
1290 
1291 MODULE_LICENSE("GPL");
1292