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 
9 /* #define VERBOSE_DEBUG */
10 
11 #include <linux/slab.h>
12 #include <linux/kernel.h>
13 #include <linux/device.h>
14 #include <linux/module.h>
15 #include <linux/usb/composite.h>
16 #include <linux/err.h>
17 
18 #include "g_zero.h"
19 #include "u_f.h"
20 
21 /*
22  * SOURCE/SINK FUNCTION ... a primary testing vehicle for USB peripheral
23  * controller drivers.
24  *
25  * This just sinks bulk packets OUT to the peripheral and sources them IN
26  * to the host, optionally with specific data patterns for integrity tests.
27  * As such it supports basic functionality and load tests.
28  *
29  * In terms of control messaging, this supports all the standard requests
30  * plus two that support control-OUT tests.  If the optional "autoresume"
31  * mode is enabled, it provides good functional coverage for the "USBCV"
32  * test harness from USB-IF.
33  */
34 struct f_sourcesink {
35 	struct usb_function	function;
36 
37 	struct usb_ep		*in_ep;
38 	struct usb_ep		*out_ep;
39 	struct usb_ep		*iso_in_ep;
40 	struct usb_ep		*iso_out_ep;
41 	int			cur_alt;
42 
43 	unsigned pattern;
44 	unsigned isoc_interval;
45 	unsigned isoc_maxpacket;
46 	unsigned isoc_mult;
47 	unsigned isoc_maxburst;
48 	unsigned buflen;
49 	unsigned bulk_qlen;
50 	unsigned iso_qlen;
51 };
52 
53 static inline struct f_sourcesink *func_to_ss(struct usb_function *f)
54 {
55 	return container_of(f, struct f_sourcesink, function);
56 }
57 
58 /*-------------------------------------------------------------------------*/
59 
60 static struct usb_interface_descriptor source_sink_intf_alt0 = {
61 	.bLength =		USB_DT_INTERFACE_SIZE,
62 	.bDescriptorType =	USB_DT_INTERFACE,
63 
64 	.bAlternateSetting =	0,
65 	.bNumEndpoints =	2,
66 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
67 	/* .iInterface		= DYNAMIC */
68 };
69 
70 static struct usb_interface_descriptor source_sink_intf_alt1 = {
71 	.bLength =		USB_DT_INTERFACE_SIZE,
72 	.bDescriptorType =	USB_DT_INTERFACE,
73 
74 	.bAlternateSetting =	1,
75 	.bNumEndpoints =	4,
76 	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
77 	/* .iInterface		= DYNAMIC */
78 };
79 
80 /* full speed support: */
81 
82 static struct usb_endpoint_descriptor fs_source_desc = {
83 	.bLength =		USB_DT_ENDPOINT_SIZE,
84 	.bDescriptorType =	USB_DT_ENDPOINT,
85 
86 	.bEndpointAddress =	USB_DIR_IN,
87 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
88 };
89 
90 static struct usb_endpoint_descriptor fs_sink_desc = {
91 	.bLength =		USB_DT_ENDPOINT_SIZE,
92 	.bDescriptorType =	USB_DT_ENDPOINT,
93 
94 	.bEndpointAddress =	USB_DIR_OUT,
95 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
96 };
97 
98 static struct usb_endpoint_descriptor fs_iso_source_desc = {
99 	.bLength =		USB_DT_ENDPOINT_SIZE,
100 	.bDescriptorType =	USB_DT_ENDPOINT,
101 
102 	.bEndpointAddress =	USB_DIR_IN,
103 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
104 	.wMaxPacketSize =	cpu_to_le16(1023),
105 	.bInterval =		4,
106 };
107 
108 static struct usb_endpoint_descriptor fs_iso_sink_desc = {
109 	.bLength =		USB_DT_ENDPOINT_SIZE,
110 	.bDescriptorType =	USB_DT_ENDPOINT,
111 
112 	.bEndpointAddress =	USB_DIR_OUT,
113 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
114 	.wMaxPacketSize =	cpu_to_le16(1023),
115 	.bInterval =		4,
116 };
117 
118 static struct usb_descriptor_header *fs_source_sink_descs[] = {
119 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
120 	(struct usb_descriptor_header *) &fs_sink_desc,
121 	(struct usb_descriptor_header *) &fs_source_desc,
122 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
123 #define FS_ALT_IFC_1_OFFSET	3
124 	(struct usb_descriptor_header *) &fs_sink_desc,
125 	(struct usb_descriptor_header *) &fs_source_desc,
126 	(struct usb_descriptor_header *) &fs_iso_sink_desc,
127 	(struct usb_descriptor_header *) &fs_iso_source_desc,
128 	NULL,
129 };
130 
131 /* high speed support: */
132 
133 static struct usb_endpoint_descriptor hs_source_desc = {
134 	.bLength =		USB_DT_ENDPOINT_SIZE,
135 	.bDescriptorType =	USB_DT_ENDPOINT,
136 
137 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
138 	.wMaxPacketSize =	cpu_to_le16(512),
139 };
140 
141 static struct usb_endpoint_descriptor hs_sink_desc = {
142 	.bLength =		USB_DT_ENDPOINT_SIZE,
143 	.bDescriptorType =	USB_DT_ENDPOINT,
144 
145 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
146 	.wMaxPacketSize =	cpu_to_le16(512),
147 };
148 
149 static struct usb_endpoint_descriptor hs_iso_source_desc = {
150 	.bLength =		USB_DT_ENDPOINT_SIZE,
151 	.bDescriptorType =	USB_DT_ENDPOINT,
152 
153 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
154 	.wMaxPacketSize =	cpu_to_le16(1024),
155 	.bInterval =		4,
156 };
157 
158 static struct usb_endpoint_descriptor hs_iso_sink_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_descriptor_header *hs_source_sink_descs[] = {
168 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
169 	(struct usb_descriptor_header *) &hs_source_desc,
170 	(struct usb_descriptor_header *) &hs_sink_desc,
171 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
172 #define HS_ALT_IFC_1_OFFSET	3
173 	(struct usb_descriptor_header *) &hs_source_desc,
174 	(struct usb_descriptor_header *) &hs_sink_desc,
175 	(struct usb_descriptor_header *) &hs_iso_source_desc,
176 	(struct usb_descriptor_header *) &hs_iso_sink_desc,
177 	NULL,
178 };
179 
180 /* super speed support: */
181 
182 static struct usb_endpoint_descriptor ss_source_desc = {
183 	.bLength =		USB_DT_ENDPOINT_SIZE,
184 	.bDescriptorType =	USB_DT_ENDPOINT,
185 
186 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
187 	.wMaxPacketSize =	cpu_to_le16(1024),
188 };
189 
190 static struct usb_ss_ep_comp_descriptor ss_source_comp_desc = {
191 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
192 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
193 
194 	.bMaxBurst =		0,
195 	.bmAttributes =		0,
196 	.wBytesPerInterval =	0,
197 };
198 
199 static struct usb_endpoint_descriptor ss_sink_desc = {
200 	.bLength =		USB_DT_ENDPOINT_SIZE,
201 	.bDescriptorType =	USB_DT_ENDPOINT,
202 
203 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
204 	.wMaxPacketSize =	cpu_to_le16(1024),
205 };
206 
207 static struct usb_ss_ep_comp_descriptor ss_sink_comp_desc = {
208 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
209 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
210 
211 	.bMaxBurst =		0,
212 	.bmAttributes =		0,
213 	.wBytesPerInterval =	0,
214 };
215 
216 static struct usb_endpoint_descriptor ss_iso_source_desc = {
217 	.bLength =		USB_DT_ENDPOINT_SIZE,
218 	.bDescriptorType =	USB_DT_ENDPOINT,
219 
220 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
221 	.wMaxPacketSize =	cpu_to_le16(1024),
222 	.bInterval =		4,
223 };
224 
225 static struct usb_ss_ep_comp_descriptor ss_iso_source_comp_desc = {
226 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
227 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
228 
229 	.bMaxBurst =		0,
230 	.bmAttributes =		0,
231 	.wBytesPerInterval =	cpu_to_le16(1024),
232 };
233 
234 static struct usb_endpoint_descriptor ss_iso_sink_desc = {
235 	.bLength =		USB_DT_ENDPOINT_SIZE,
236 	.bDescriptorType =	USB_DT_ENDPOINT,
237 
238 	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
239 	.wMaxPacketSize =	cpu_to_le16(1024),
240 	.bInterval =		4,
241 };
242 
243 static struct usb_ss_ep_comp_descriptor ss_iso_sink_comp_desc = {
244 	.bLength =		USB_DT_SS_EP_COMP_SIZE,
245 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
246 
247 	.bMaxBurst =		0,
248 	.bmAttributes =		0,
249 	.wBytesPerInterval =	cpu_to_le16(1024),
250 };
251 
252 static struct usb_descriptor_header *ss_source_sink_descs[] = {
253 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
254 	(struct usb_descriptor_header *) &ss_source_desc,
255 	(struct usb_descriptor_header *) &ss_source_comp_desc,
256 	(struct usb_descriptor_header *) &ss_sink_desc,
257 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
258 	(struct usb_descriptor_header *) &source_sink_intf_alt1,
259 #define SS_ALT_IFC_1_OFFSET	5
260 	(struct usb_descriptor_header *) &ss_source_desc,
261 	(struct usb_descriptor_header *) &ss_source_comp_desc,
262 	(struct usb_descriptor_header *) &ss_sink_desc,
263 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
264 	(struct usb_descriptor_header *) &ss_iso_source_desc,
265 	(struct usb_descriptor_header *) &ss_iso_source_comp_desc,
266 	(struct usb_descriptor_header *) &ss_iso_sink_desc,
267 	(struct usb_descriptor_header *) &ss_iso_sink_comp_desc,
268 	NULL,
269 };
270 
271 /* function-specific strings: */
272 
273 static struct usb_string strings_sourcesink[] = {
274 	[0].s = "source and sink data",
275 	{  }			/* end of list */
276 };
277 
278 static struct usb_gadget_strings stringtab_sourcesink = {
279 	.language	= 0x0409,	/* en-us */
280 	.strings	= strings_sourcesink,
281 };
282 
283 static struct usb_gadget_strings *sourcesink_strings[] = {
284 	&stringtab_sourcesink,
285 	NULL,
286 };
287 
288 /*-------------------------------------------------------------------------*/
289 
290 static inline struct usb_request *ss_alloc_ep_req(struct usb_ep *ep, int len)
291 {
292 	return alloc_ep_req(ep, len);
293 }
294 
295 static void disable_ep(struct usb_composite_dev *cdev, struct usb_ep *ep)
296 {
297 	int			value;
298 
299 	value = usb_ep_disable(ep);
300 	if (value < 0)
301 		DBG(cdev, "disable %s --> %d\n", ep->name, value);
302 }
303 
304 void disable_endpoints(struct usb_composite_dev *cdev,
305 		struct usb_ep *in, struct usb_ep *out,
306 		struct usb_ep *iso_in, struct usb_ep *iso_out)
307 {
308 	disable_ep(cdev, in);
309 	disable_ep(cdev, out);
310 	if (iso_in)
311 		disable_ep(cdev, iso_in);
312 	if (iso_out)
313 		disable_ep(cdev, iso_out);
314 }
315 
316 static int
317 sourcesink_bind(struct usb_configuration *c, struct usb_function *f)
318 {
319 	struct usb_composite_dev *cdev = c->cdev;
320 	struct f_sourcesink	*ss = func_to_ss(f);
321 	int	id;
322 	int ret;
323 
324 	/* allocate interface ID(s) */
325 	id = usb_interface_id(c, f);
326 	if (id < 0)
327 		return id;
328 	source_sink_intf_alt0.bInterfaceNumber = id;
329 	source_sink_intf_alt1.bInterfaceNumber = id;
330 
331 	/* allocate bulk endpoints */
332 	ss->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_source_desc);
333 	if (!ss->in_ep) {
334 autoconf_fail:
335 		ERROR(cdev, "%s: can't autoconfigure on %s\n",
336 			f->name, cdev->gadget->name);
337 		return -ENODEV;
338 	}
339 
340 	ss->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_sink_desc);
341 	if (!ss->out_ep)
342 		goto autoconf_fail;
343 
344 	/* sanity check the isoc module parameters */
345 	if (ss->isoc_interval < 1)
346 		ss->isoc_interval = 1;
347 	if (ss->isoc_interval > 16)
348 		ss->isoc_interval = 16;
349 	if (ss->isoc_mult > 2)
350 		ss->isoc_mult = 2;
351 	if (ss->isoc_maxburst > 15)
352 		ss->isoc_maxburst = 15;
353 
354 	/* fill in the FS isoc descriptors from the module parameters */
355 	fs_iso_source_desc.wMaxPacketSize = ss->isoc_maxpacket > 1023 ?
356 						1023 : ss->isoc_maxpacket;
357 	fs_iso_source_desc.bInterval = ss->isoc_interval;
358 	fs_iso_sink_desc.wMaxPacketSize = ss->isoc_maxpacket > 1023 ?
359 						1023 : ss->isoc_maxpacket;
360 	fs_iso_sink_desc.bInterval = ss->isoc_interval;
361 
362 	/* allocate iso endpoints */
363 	ss->iso_in_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_source_desc);
364 	if (!ss->iso_in_ep)
365 		goto no_iso;
366 
367 	ss->iso_out_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_sink_desc);
368 	if (!ss->iso_out_ep) {
369 		usb_ep_autoconfig_release(ss->iso_in_ep);
370 		ss->iso_in_ep = NULL;
371 no_iso:
372 		/*
373 		 * We still want to work even if the UDC doesn't have isoc
374 		 * endpoints, so null out the alt interface that contains
375 		 * them and continue.
376 		 */
377 		fs_source_sink_descs[FS_ALT_IFC_1_OFFSET] = NULL;
378 		hs_source_sink_descs[HS_ALT_IFC_1_OFFSET] = NULL;
379 		ss_source_sink_descs[SS_ALT_IFC_1_OFFSET] = NULL;
380 	}
381 
382 	if (ss->isoc_maxpacket > 1024)
383 		ss->isoc_maxpacket = 1024;
384 
385 	/* support high speed hardware */
386 	hs_source_desc.bEndpointAddress = fs_source_desc.bEndpointAddress;
387 	hs_sink_desc.bEndpointAddress = fs_sink_desc.bEndpointAddress;
388 
389 	/*
390 	 * Fill in the HS isoc descriptors from the module parameters.
391 	 * We assume that the user knows what they are doing and won't
392 	 * give parameters that their UDC doesn't support.
393 	 */
394 	hs_iso_source_desc.wMaxPacketSize = ss->isoc_maxpacket;
395 	hs_iso_source_desc.wMaxPacketSize |= ss->isoc_mult << 11;
396 	hs_iso_source_desc.bInterval = ss->isoc_interval;
397 	hs_iso_source_desc.bEndpointAddress =
398 		fs_iso_source_desc.bEndpointAddress;
399 
400 	hs_iso_sink_desc.wMaxPacketSize = ss->isoc_maxpacket;
401 	hs_iso_sink_desc.wMaxPacketSize |= ss->isoc_mult << 11;
402 	hs_iso_sink_desc.bInterval = ss->isoc_interval;
403 	hs_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
404 
405 	/* support super speed hardware */
406 	ss_source_desc.bEndpointAddress =
407 		fs_source_desc.bEndpointAddress;
408 	ss_sink_desc.bEndpointAddress =
409 		fs_sink_desc.bEndpointAddress;
410 
411 	/*
412 	 * Fill in the SS isoc descriptors from the module parameters.
413 	 * We assume that the user knows what they are doing and won't
414 	 * give parameters that their UDC doesn't support.
415 	 */
416 	ss_iso_source_desc.wMaxPacketSize = ss->isoc_maxpacket;
417 	ss_iso_source_desc.bInterval = ss->isoc_interval;
418 	ss_iso_source_comp_desc.bmAttributes = ss->isoc_mult;
419 	ss_iso_source_comp_desc.bMaxBurst = ss->isoc_maxburst;
420 	ss_iso_source_comp_desc.wBytesPerInterval = ss->isoc_maxpacket *
421 		(ss->isoc_mult + 1) * (ss->isoc_maxburst + 1);
422 	ss_iso_source_desc.bEndpointAddress =
423 		fs_iso_source_desc.bEndpointAddress;
424 
425 	ss_iso_sink_desc.wMaxPacketSize = ss->isoc_maxpacket;
426 	ss_iso_sink_desc.bInterval = ss->isoc_interval;
427 	ss_iso_sink_comp_desc.bmAttributes = ss->isoc_mult;
428 	ss_iso_sink_comp_desc.bMaxBurst = ss->isoc_maxburst;
429 	ss_iso_sink_comp_desc.wBytesPerInterval = ss->isoc_maxpacket *
430 		(ss->isoc_mult + 1) * (ss->isoc_maxburst + 1);
431 	ss_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
432 
433 	ret = usb_assign_descriptors(f, fs_source_sink_descs,
434 			hs_source_sink_descs, ss_source_sink_descs, NULL);
435 	if (ret)
436 		return ret;
437 
438 	DBG(cdev, "%s speed %s: IN/%s, OUT/%s, ISO-IN/%s, ISO-OUT/%s\n",
439 	    (gadget_is_superspeed(c->cdev->gadget) ? "super" :
440 	     (gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full")),
441 			f->name, ss->in_ep->name, ss->out_ep->name,
442 			ss->iso_in_ep ? ss->iso_in_ep->name : "<none>",
443 			ss->iso_out_ep ? ss->iso_out_ep->name : "<none>");
444 	return 0;
445 }
446 
447 static void
448 sourcesink_free_func(struct usb_function *f)
449 {
450 	struct f_ss_opts *opts;
451 
452 	opts = container_of(f->fi, struct f_ss_opts, func_inst);
453 
454 	mutex_lock(&opts->lock);
455 	opts->refcnt--;
456 	mutex_unlock(&opts->lock);
457 
458 	usb_free_all_descriptors(f);
459 	kfree(func_to_ss(f));
460 }
461 
462 /* optionally require specific source/sink data patterns  */
463 static int check_read_data(struct f_sourcesink *ss, struct usb_request *req)
464 {
465 	unsigned		i;
466 	u8			*buf = req->buf;
467 	struct usb_composite_dev *cdev = ss->function.config->cdev;
468 	int max_packet_size = le16_to_cpu(ss->out_ep->desc->wMaxPacketSize);
469 
470 	if (ss->pattern == 2)
471 		return 0;
472 
473 	for (i = 0; i < req->actual; i++, buf++) {
474 		switch (ss->pattern) {
475 
476 		/* all-zeroes has no synchronization issues */
477 		case 0:
478 			if (*buf == 0)
479 				continue;
480 			break;
481 
482 		/* "mod63" stays in sync with short-terminated transfers,
483 		 * OR otherwise when host and gadget agree on how large
484 		 * each usb transfer request should be.  Resync is done
485 		 * with set_interface or set_config.  (We *WANT* it to
486 		 * get quickly out of sync if controllers or their drivers
487 		 * stutter for any reason, including buffer duplication...)
488 		 */
489 		case 1:
490 			if (*buf == (u8)((i % max_packet_size) % 63))
491 				continue;
492 			break;
493 		}
494 		ERROR(cdev, "bad OUT byte, buf[%d] = %d\n", i, *buf);
495 		usb_ep_set_halt(ss->out_ep);
496 		return -EINVAL;
497 	}
498 	return 0;
499 }
500 
501 static void reinit_write_data(struct usb_ep *ep, struct usb_request *req)
502 {
503 	unsigned	i;
504 	u8		*buf = req->buf;
505 	int max_packet_size = le16_to_cpu(ep->desc->wMaxPacketSize);
506 	struct f_sourcesink *ss = ep->driver_data;
507 
508 	switch (ss->pattern) {
509 	case 0:
510 		memset(req->buf, 0, req->length);
511 		break;
512 	case 1:
513 		for  (i = 0; i < req->length; i++)
514 			*buf++ = (u8) ((i % max_packet_size) % 63);
515 		break;
516 	case 2:
517 		break;
518 	}
519 }
520 
521 static void source_sink_complete(struct usb_ep *ep, struct usb_request *req)
522 {
523 	struct usb_composite_dev	*cdev;
524 	struct f_sourcesink		*ss = ep->driver_data;
525 	int				status = req->status;
526 
527 	/* driver_data will be null if ep has been disabled */
528 	if (!ss)
529 		return;
530 
531 	cdev = ss->function.config->cdev;
532 
533 	switch (status) {
534 
535 	case 0:				/* normal completion? */
536 		if (ep == ss->out_ep) {
537 			check_read_data(ss, req);
538 			if (ss->pattern != 2)
539 				memset(req->buf, 0x55, req->length);
540 		}
541 		break;
542 
543 	/* this endpoint is normally active while we're configured */
544 	case -ECONNABORTED:		/* hardware forced ep reset */
545 	case -ECONNRESET:		/* request dequeued */
546 	case -ESHUTDOWN:		/* disconnect from host */
547 		VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
548 				req->actual, req->length);
549 		if (ep == ss->out_ep)
550 			check_read_data(ss, req);
551 		free_ep_req(ep, req);
552 		return;
553 
554 	case -EOVERFLOW:		/* buffer overrun on read means that
555 					 * we didn't provide a big enough
556 					 * buffer.
557 					 */
558 	default:
559 #if 1
560 		DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
561 				status, req->actual, req->length);
562 		break;
563 #endif
564 	case -EREMOTEIO:		/* short read */
565 		break;
566 	}
567 
568 	status = usb_ep_queue(ep, req, GFP_ATOMIC);
569 	if (status) {
570 		ERROR(cdev, "kill %s:  resubmit %d bytes --> %d\n",
571 				ep->name, req->length, status);
572 		usb_ep_set_halt(ep);
573 		/* FIXME recover later ... somehow */
574 	}
575 }
576 
577 static int source_sink_start_ep(struct f_sourcesink *ss, bool is_in,
578 		bool is_iso, int speed)
579 {
580 	struct usb_ep		*ep;
581 	struct usb_request	*req;
582 	int			i, size, qlen, status = 0;
583 
584 	if (is_iso) {
585 		switch (speed) {
586 		case USB_SPEED_SUPER:
587 			size = ss->isoc_maxpacket *
588 					(ss->isoc_mult + 1) *
589 					(ss->isoc_maxburst + 1);
590 			break;
591 		case USB_SPEED_HIGH:
592 			size = ss->isoc_maxpacket * (ss->isoc_mult + 1);
593 			break;
594 		default:
595 			size = ss->isoc_maxpacket > 1023 ?
596 					1023 : ss->isoc_maxpacket;
597 			break;
598 		}
599 		ep = is_in ? ss->iso_in_ep : ss->iso_out_ep;
600 		qlen = ss->iso_qlen;
601 	} else {
602 		ep = is_in ? ss->in_ep : ss->out_ep;
603 		qlen = ss->bulk_qlen;
604 		size = ss->buflen;
605 	}
606 
607 	for (i = 0; i < qlen; i++) {
608 		req = ss_alloc_ep_req(ep, size);
609 		if (!req)
610 			return -ENOMEM;
611 
612 		req->complete = source_sink_complete;
613 		if (is_in)
614 			reinit_write_data(ep, req);
615 		else if (ss->pattern != 2)
616 			memset(req->buf, 0x55, req->length);
617 
618 		status = usb_ep_queue(ep, req, GFP_ATOMIC);
619 		if (status) {
620 			struct usb_composite_dev	*cdev;
621 
622 			cdev = ss->function.config->cdev;
623 			ERROR(cdev, "start %s%s %s --> %d\n",
624 			      is_iso ? "ISO-" : "", is_in ? "IN" : "OUT",
625 			      ep->name, status);
626 			free_ep_req(ep, req);
627 			return status;
628 		}
629 	}
630 
631 	return status;
632 }
633 
634 static void disable_source_sink(struct f_sourcesink *ss)
635 {
636 	struct usb_composite_dev	*cdev;
637 
638 	cdev = ss->function.config->cdev;
639 	disable_endpoints(cdev, ss->in_ep, ss->out_ep, ss->iso_in_ep,
640 			ss->iso_out_ep);
641 	VDBG(cdev, "%s disabled\n", ss->function.name);
642 }
643 
644 static int
645 enable_source_sink(struct usb_composite_dev *cdev, struct f_sourcesink *ss,
646 		int alt)
647 {
648 	int					result = 0;
649 	int					speed = cdev->gadget->speed;
650 	struct usb_ep				*ep;
651 
652 	/* one bulk endpoint writes (sources) zeroes IN (to the host) */
653 	ep = ss->in_ep;
654 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
655 	if (result)
656 		return result;
657 	result = usb_ep_enable(ep);
658 	if (result < 0)
659 		return result;
660 	ep->driver_data = ss;
661 
662 	result = source_sink_start_ep(ss, true, false, speed);
663 	if (result < 0) {
664 fail:
665 		ep = ss->in_ep;
666 		usb_ep_disable(ep);
667 		return result;
668 	}
669 
670 	/* one bulk endpoint reads (sinks) anything OUT (from the host) */
671 	ep = ss->out_ep;
672 	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
673 	if (result)
674 		goto fail;
675 	result = usb_ep_enable(ep);
676 	if (result < 0)
677 		goto fail;
678 	ep->driver_data = ss;
679 
680 	result = source_sink_start_ep(ss, false, false, speed);
681 	if (result < 0) {
682 fail2:
683 		ep = ss->out_ep;
684 		usb_ep_disable(ep);
685 		goto fail;
686 	}
687 
688 	if (alt == 0)
689 		goto out;
690 
691 	/* one iso endpoint writes (sources) zeroes IN (to the host) */
692 	ep = ss->iso_in_ep;
693 	if (ep) {
694 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
695 		if (result)
696 			goto fail2;
697 		result = usb_ep_enable(ep);
698 		if (result < 0)
699 			goto fail2;
700 		ep->driver_data = ss;
701 
702 		result = source_sink_start_ep(ss, true, true, speed);
703 		if (result < 0) {
704 fail3:
705 			ep = ss->iso_in_ep;
706 			if (ep)
707 				usb_ep_disable(ep);
708 			goto fail2;
709 		}
710 	}
711 
712 	/* one iso endpoint reads (sinks) anything OUT (from the host) */
713 	ep = ss->iso_out_ep;
714 	if (ep) {
715 		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
716 		if (result)
717 			goto fail3;
718 		result = usb_ep_enable(ep);
719 		if (result < 0)
720 			goto fail3;
721 		ep->driver_data = ss;
722 
723 		result = source_sink_start_ep(ss, false, true, speed);
724 		if (result < 0) {
725 			usb_ep_disable(ep);
726 			goto fail3;
727 		}
728 	}
729 out:
730 	ss->cur_alt = alt;
731 
732 	DBG(cdev, "%s enabled, alt intf %d\n", ss->function.name, alt);
733 	return result;
734 }
735 
736 static int sourcesink_set_alt(struct usb_function *f,
737 		unsigned intf, unsigned alt)
738 {
739 	struct f_sourcesink		*ss = func_to_ss(f);
740 	struct usb_composite_dev	*cdev = f->config->cdev;
741 
742 	disable_source_sink(ss);
743 	return enable_source_sink(cdev, ss, alt);
744 }
745 
746 static int sourcesink_get_alt(struct usb_function *f, unsigned intf)
747 {
748 	struct f_sourcesink		*ss = func_to_ss(f);
749 
750 	return ss->cur_alt;
751 }
752 
753 static void sourcesink_disable(struct usb_function *f)
754 {
755 	struct f_sourcesink	*ss = func_to_ss(f);
756 
757 	disable_source_sink(ss);
758 }
759 
760 /*-------------------------------------------------------------------------*/
761 
762 static int sourcesink_setup(struct usb_function *f,
763 		const struct usb_ctrlrequest *ctrl)
764 {
765 	struct usb_configuration        *c = f->config;
766 	struct usb_request	*req = c->cdev->req;
767 	int			value = -EOPNOTSUPP;
768 	u16			w_index = le16_to_cpu(ctrl->wIndex);
769 	u16			w_value = le16_to_cpu(ctrl->wValue);
770 	u16			w_length = le16_to_cpu(ctrl->wLength);
771 
772 	req->length = USB_COMP_EP0_BUFSIZ;
773 
774 	/* composite driver infrastructure handles everything except
775 	 * the two control test requests.
776 	 */
777 	switch (ctrl->bRequest) {
778 
779 	/*
780 	 * These are the same vendor-specific requests supported by
781 	 * Intel's USB 2.0 compliance test devices.  We exceed that
782 	 * device spec by allowing multiple-packet requests.
783 	 *
784 	 * NOTE:  the Control-OUT data stays in req->buf ... better
785 	 * would be copying it into a scratch buffer, so that other
786 	 * requests may safely intervene.
787 	 */
788 	case 0x5b:	/* control WRITE test -- fill the buffer */
789 		if (ctrl->bRequestType != (USB_DIR_OUT|USB_TYPE_VENDOR))
790 			goto unknown;
791 		if (w_value || w_index)
792 			break;
793 		/* just read that many bytes into the buffer */
794 		if (w_length > req->length)
795 			break;
796 		value = w_length;
797 		break;
798 	case 0x5c:	/* control READ test -- return the buffer */
799 		if (ctrl->bRequestType != (USB_DIR_IN|USB_TYPE_VENDOR))
800 			goto unknown;
801 		if (w_value || w_index)
802 			break;
803 		/* expect those bytes are still in the buffer; send back */
804 		if (w_length > req->length)
805 			break;
806 		value = w_length;
807 		break;
808 
809 	default:
810 unknown:
811 		VDBG(c->cdev,
812 			"unknown control req%02x.%02x v%04x i%04x l%d\n",
813 			ctrl->bRequestType, ctrl->bRequest,
814 			w_value, w_index, w_length);
815 	}
816 
817 	/* respond with data transfer or status phase? */
818 	if (value >= 0) {
819 		VDBG(c->cdev, "source/sink req%02x.%02x v%04x i%04x l%d\n",
820 			ctrl->bRequestType, ctrl->bRequest,
821 			w_value, w_index, w_length);
822 		req->zero = 0;
823 		req->length = value;
824 		value = usb_ep_queue(c->cdev->gadget->ep0, req, GFP_ATOMIC);
825 		if (value < 0)
826 			ERROR(c->cdev, "source/sink response, err %d\n",
827 					value);
828 	}
829 
830 	/* device either stalls (value < 0) or reports success */
831 	return value;
832 }
833 
834 static struct usb_function *source_sink_alloc_func(
835 		struct usb_function_instance *fi)
836 {
837 	struct f_sourcesink     *ss;
838 	struct f_ss_opts	*ss_opts;
839 
840 	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
841 	if (!ss)
842 		return ERR_PTR(-ENOMEM);
843 
844 	ss_opts =  container_of(fi, struct f_ss_opts, func_inst);
845 
846 	mutex_lock(&ss_opts->lock);
847 	ss_opts->refcnt++;
848 	mutex_unlock(&ss_opts->lock);
849 
850 	ss->pattern = ss_opts->pattern;
851 	ss->isoc_interval = ss_opts->isoc_interval;
852 	ss->isoc_maxpacket = ss_opts->isoc_maxpacket;
853 	ss->isoc_mult = ss_opts->isoc_mult;
854 	ss->isoc_maxburst = ss_opts->isoc_maxburst;
855 	ss->buflen = ss_opts->bulk_buflen;
856 	ss->bulk_qlen = ss_opts->bulk_qlen;
857 	ss->iso_qlen = ss_opts->iso_qlen;
858 
859 	ss->function.name = "source/sink";
860 	ss->function.bind = sourcesink_bind;
861 	ss->function.set_alt = sourcesink_set_alt;
862 	ss->function.get_alt = sourcesink_get_alt;
863 	ss->function.disable = sourcesink_disable;
864 	ss->function.setup = sourcesink_setup;
865 	ss->function.strings = sourcesink_strings;
866 
867 	ss->function.free_func = sourcesink_free_func;
868 
869 	return &ss->function;
870 }
871 
872 static inline struct f_ss_opts *to_f_ss_opts(struct config_item *item)
873 {
874 	return container_of(to_config_group(item), struct f_ss_opts,
875 			    func_inst.group);
876 }
877 
878 static void ss_attr_release(struct config_item *item)
879 {
880 	struct f_ss_opts *ss_opts = to_f_ss_opts(item);
881 
882 	usb_put_function_instance(&ss_opts->func_inst);
883 }
884 
885 static struct configfs_item_operations ss_item_ops = {
886 	.release		= ss_attr_release,
887 };
888 
889 static ssize_t f_ss_opts_pattern_show(struct config_item *item, char *page)
890 {
891 	struct f_ss_opts *opts = to_f_ss_opts(item);
892 	int result;
893 
894 	mutex_lock(&opts->lock);
895 	result = sprintf(page, "%u\n", opts->pattern);
896 	mutex_unlock(&opts->lock);
897 
898 	return result;
899 }
900 
901 static ssize_t f_ss_opts_pattern_store(struct config_item *item,
902 				       const char *page, size_t len)
903 {
904 	struct f_ss_opts *opts = to_f_ss_opts(item);
905 	int ret;
906 	u8 num;
907 
908 	mutex_lock(&opts->lock);
909 	if (opts->refcnt) {
910 		ret = -EBUSY;
911 		goto end;
912 	}
913 
914 	ret = kstrtou8(page, 0, &num);
915 	if (ret)
916 		goto end;
917 
918 	if (num != 0 && num != 1 && num != 2) {
919 		ret = -EINVAL;
920 		goto end;
921 	}
922 
923 	opts->pattern = num;
924 	ret = len;
925 end:
926 	mutex_unlock(&opts->lock);
927 	return ret;
928 }
929 
930 CONFIGFS_ATTR(f_ss_opts_, pattern);
931 
932 static ssize_t f_ss_opts_isoc_interval_show(struct config_item *item, char *page)
933 {
934 	struct f_ss_opts *opts = to_f_ss_opts(item);
935 	int result;
936 
937 	mutex_lock(&opts->lock);
938 	result = sprintf(page, "%u\n", opts->isoc_interval);
939 	mutex_unlock(&opts->lock);
940 
941 	return result;
942 }
943 
944 static ssize_t f_ss_opts_isoc_interval_store(struct config_item *item,
945 				       const char *page, size_t len)
946 {
947 	struct f_ss_opts *opts = to_f_ss_opts(item);
948 	int ret;
949 	u8 num;
950 
951 	mutex_lock(&opts->lock);
952 	if (opts->refcnt) {
953 		ret = -EBUSY;
954 		goto end;
955 	}
956 
957 	ret = kstrtou8(page, 0, &num);
958 	if (ret)
959 		goto end;
960 
961 	if (num > 16) {
962 		ret = -EINVAL;
963 		goto end;
964 	}
965 
966 	opts->isoc_interval = num;
967 	ret = len;
968 end:
969 	mutex_unlock(&opts->lock);
970 	return ret;
971 }
972 
973 CONFIGFS_ATTR(f_ss_opts_, isoc_interval);
974 
975 static ssize_t f_ss_opts_isoc_maxpacket_show(struct config_item *item, char *page)
976 {
977 	struct f_ss_opts *opts = to_f_ss_opts(item);
978 	int result;
979 
980 	mutex_lock(&opts->lock);
981 	result = sprintf(page, "%u\n", opts->isoc_maxpacket);
982 	mutex_unlock(&opts->lock);
983 
984 	return result;
985 }
986 
987 static ssize_t f_ss_opts_isoc_maxpacket_store(struct config_item *item,
988 				       const char *page, size_t len)
989 {
990 	struct f_ss_opts *opts = to_f_ss_opts(item);
991 	int ret;
992 	u16 num;
993 
994 	mutex_lock(&opts->lock);
995 	if (opts->refcnt) {
996 		ret = -EBUSY;
997 		goto end;
998 	}
999 
1000 	ret = kstrtou16(page, 0, &num);
1001 	if (ret)
1002 		goto end;
1003 
1004 	if (num > 1024) {
1005 		ret = -EINVAL;
1006 		goto end;
1007 	}
1008 
1009 	opts->isoc_maxpacket = num;
1010 	ret = len;
1011 end:
1012 	mutex_unlock(&opts->lock);
1013 	return ret;
1014 }
1015 
1016 CONFIGFS_ATTR(f_ss_opts_, isoc_maxpacket);
1017 
1018 static ssize_t f_ss_opts_isoc_mult_show(struct config_item *item, char *page)
1019 {
1020 	struct f_ss_opts *opts = to_f_ss_opts(item);
1021 	int result;
1022 
1023 	mutex_lock(&opts->lock);
1024 	result = sprintf(page, "%u\n", opts->isoc_mult);
1025 	mutex_unlock(&opts->lock);
1026 
1027 	return result;
1028 }
1029 
1030 static ssize_t f_ss_opts_isoc_mult_store(struct config_item *item,
1031 				       const char *page, size_t len)
1032 {
1033 	struct f_ss_opts *opts = to_f_ss_opts(item);
1034 	int ret;
1035 	u8 num;
1036 
1037 	mutex_lock(&opts->lock);
1038 	if (opts->refcnt) {
1039 		ret = -EBUSY;
1040 		goto end;
1041 	}
1042 
1043 	ret = kstrtou8(page, 0, &num);
1044 	if (ret)
1045 		goto end;
1046 
1047 	if (num > 2) {
1048 		ret = -EINVAL;
1049 		goto end;
1050 	}
1051 
1052 	opts->isoc_mult = num;
1053 	ret = len;
1054 end:
1055 	mutex_unlock(&opts->lock);
1056 	return ret;
1057 }
1058 
1059 CONFIGFS_ATTR(f_ss_opts_, isoc_mult);
1060 
1061 static ssize_t f_ss_opts_isoc_maxburst_show(struct config_item *item, char *page)
1062 {
1063 	struct f_ss_opts *opts = to_f_ss_opts(item);
1064 	int result;
1065 
1066 	mutex_lock(&opts->lock);
1067 	result = sprintf(page, "%u\n", opts->isoc_maxburst);
1068 	mutex_unlock(&opts->lock);
1069 
1070 	return result;
1071 }
1072 
1073 static ssize_t f_ss_opts_isoc_maxburst_store(struct config_item *item,
1074 				       const char *page, size_t len)
1075 {
1076 	struct f_ss_opts *opts = to_f_ss_opts(item);
1077 	int ret;
1078 	u8 num;
1079 
1080 	mutex_lock(&opts->lock);
1081 	if (opts->refcnt) {
1082 		ret = -EBUSY;
1083 		goto end;
1084 	}
1085 
1086 	ret = kstrtou8(page, 0, &num);
1087 	if (ret)
1088 		goto end;
1089 
1090 	if (num > 15) {
1091 		ret = -EINVAL;
1092 		goto end;
1093 	}
1094 
1095 	opts->isoc_maxburst = num;
1096 	ret = len;
1097 end:
1098 	mutex_unlock(&opts->lock);
1099 	return ret;
1100 }
1101 
1102 CONFIGFS_ATTR(f_ss_opts_, isoc_maxburst);
1103 
1104 static ssize_t f_ss_opts_bulk_buflen_show(struct config_item *item, char *page)
1105 {
1106 	struct f_ss_opts *opts = to_f_ss_opts(item);
1107 	int result;
1108 
1109 	mutex_lock(&opts->lock);
1110 	result = sprintf(page, "%u\n", opts->bulk_buflen);
1111 	mutex_unlock(&opts->lock);
1112 
1113 	return result;
1114 }
1115 
1116 static ssize_t f_ss_opts_bulk_buflen_store(struct config_item *item,
1117 					   const char *page, size_t len)
1118 {
1119 	struct f_ss_opts *opts = to_f_ss_opts(item);
1120 	int ret;
1121 	u32 num;
1122 
1123 	mutex_lock(&opts->lock);
1124 	if (opts->refcnt) {
1125 		ret = -EBUSY;
1126 		goto end;
1127 	}
1128 
1129 	ret = kstrtou32(page, 0, &num);
1130 	if (ret)
1131 		goto end;
1132 
1133 	opts->bulk_buflen = num;
1134 	ret = len;
1135 end:
1136 	mutex_unlock(&opts->lock);
1137 	return ret;
1138 }
1139 
1140 CONFIGFS_ATTR(f_ss_opts_, bulk_buflen);
1141 
1142 static ssize_t f_ss_opts_bulk_qlen_show(struct config_item *item, char *page)
1143 {
1144 	struct f_ss_opts *opts = to_f_ss_opts(item);
1145 	int result;
1146 
1147 	mutex_lock(&opts->lock);
1148 	result = sprintf(page, "%u\n", opts->bulk_qlen);
1149 	mutex_unlock(&opts->lock);
1150 
1151 	return result;
1152 }
1153 
1154 static ssize_t f_ss_opts_bulk_qlen_store(struct config_item *item,
1155 					   const char *page, size_t len)
1156 {
1157 	struct f_ss_opts *opts = to_f_ss_opts(item);
1158 	int ret;
1159 	u32 num;
1160 
1161 	mutex_lock(&opts->lock);
1162 	if (opts->refcnt) {
1163 		ret = -EBUSY;
1164 		goto end;
1165 	}
1166 
1167 	ret = kstrtou32(page, 0, &num);
1168 	if (ret)
1169 		goto end;
1170 
1171 	opts->bulk_qlen = num;
1172 	ret = len;
1173 end:
1174 	mutex_unlock(&opts->lock);
1175 	return ret;
1176 }
1177 
1178 CONFIGFS_ATTR(f_ss_opts_, bulk_qlen);
1179 
1180 static ssize_t f_ss_opts_iso_qlen_show(struct config_item *item, char *page)
1181 {
1182 	struct f_ss_opts *opts = to_f_ss_opts(item);
1183 	int result;
1184 
1185 	mutex_lock(&opts->lock);
1186 	result = sprintf(page, "%u\n", opts->iso_qlen);
1187 	mutex_unlock(&opts->lock);
1188 
1189 	return result;
1190 }
1191 
1192 static ssize_t f_ss_opts_iso_qlen_store(struct config_item *item,
1193 					   const char *page, size_t len)
1194 {
1195 	struct f_ss_opts *opts = to_f_ss_opts(item);
1196 	int ret;
1197 	u32 num;
1198 
1199 	mutex_lock(&opts->lock);
1200 	if (opts->refcnt) {
1201 		ret = -EBUSY;
1202 		goto end;
1203 	}
1204 
1205 	ret = kstrtou32(page, 0, &num);
1206 	if (ret)
1207 		goto end;
1208 
1209 	opts->iso_qlen = num;
1210 	ret = len;
1211 end:
1212 	mutex_unlock(&opts->lock);
1213 	return ret;
1214 }
1215 
1216 CONFIGFS_ATTR(f_ss_opts_, iso_qlen);
1217 
1218 static struct configfs_attribute *ss_attrs[] = {
1219 	&f_ss_opts_attr_pattern,
1220 	&f_ss_opts_attr_isoc_interval,
1221 	&f_ss_opts_attr_isoc_maxpacket,
1222 	&f_ss_opts_attr_isoc_mult,
1223 	&f_ss_opts_attr_isoc_maxburst,
1224 	&f_ss_opts_attr_bulk_buflen,
1225 	&f_ss_opts_attr_bulk_qlen,
1226 	&f_ss_opts_attr_iso_qlen,
1227 	NULL,
1228 };
1229 
1230 static const struct config_item_type ss_func_type = {
1231 	.ct_item_ops    = &ss_item_ops,
1232 	.ct_attrs	= ss_attrs,
1233 	.ct_owner       = THIS_MODULE,
1234 };
1235 
1236 static void source_sink_free_instance(struct usb_function_instance *fi)
1237 {
1238 	struct f_ss_opts *ss_opts;
1239 
1240 	ss_opts = container_of(fi, struct f_ss_opts, func_inst);
1241 	kfree(ss_opts);
1242 }
1243 
1244 static struct usb_function_instance *source_sink_alloc_inst(void)
1245 {
1246 	struct f_ss_opts *ss_opts;
1247 
1248 	ss_opts = kzalloc(sizeof(*ss_opts), GFP_KERNEL);
1249 	if (!ss_opts)
1250 		return ERR_PTR(-ENOMEM);
1251 	mutex_init(&ss_opts->lock);
1252 	ss_opts->func_inst.free_func_inst = source_sink_free_instance;
1253 	ss_opts->isoc_interval = GZERO_ISOC_INTERVAL;
1254 	ss_opts->isoc_maxpacket = GZERO_ISOC_MAXPACKET;
1255 	ss_opts->bulk_buflen = GZERO_BULK_BUFLEN;
1256 	ss_opts->bulk_qlen = GZERO_SS_BULK_QLEN;
1257 	ss_opts->iso_qlen = GZERO_SS_ISO_QLEN;
1258 
1259 	config_group_init_type_name(&ss_opts->func_inst.group, "",
1260 				    &ss_func_type);
1261 
1262 	return &ss_opts->func_inst;
1263 }
1264 DECLARE_USB_FUNCTION(SourceSink, source_sink_alloc_inst,
1265 		source_sink_alloc_func);
1266 
1267 static int __init sslb_modinit(void)
1268 {
1269 	int ret;
1270 
1271 	ret = usb_function_register(&SourceSinkusb_func);
1272 	if (ret)
1273 		return ret;
1274 	ret = lb_modinit();
1275 	if (ret)
1276 		usb_function_unregister(&SourceSinkusb_func);
1277 	return ret;
1278 }
1279 static void __exit sslb_modexit(void)
1280 {
1281 	usb_function_unregister(&SourceSinkusb_func);
1282 	lb_modexit();
1283 }
1284 module_init(sslb_modinit);
1285 module_exit(sslb_modexit);
1286 
1287 MODULE_LICENSE("GPL");
1288