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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Wireless USB - Cable Based Association
4 *
5 *
6 * Copyright (C) 2006 Intel Corporation
7 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
8 * Copyright (C) 2008 Cambridge Silicon Radio Ltd.
9 *
10 * WUSB devices have to be paired (associated in WUSB lingo) so
11 * that they can connect to the system.
12 *
13 * One way of pairing is using CBA-Cable Based Association. First
14 * time you plug the device with a cable, association is done between
15 * host and device and subsequent times, you can connect wirelessly
16 * without having to associate again. That's the idea.
17 *
18 * This driver does nothing Earth shattering. It just provides an
19 * interface to chat with the wire-connected device so we can get a
20 * CDID (device ID) that might have been previously associated to a
21 * CHID (host ID) and to set up a new <CHID,CDID,CK> triplet
22 * (connection context), with the CK being the secret, or connection
23 * key. This is the pairing data.
24 *
25 * When a device with the CBA capability connects, the probe routine
26 * just creates a bunch of sysfs files that a user space enumeration
27 * manager uses to allow it to connect wirelessly to the system or not.
28 *
29 * The process goes like this:
30 *
31 * 1. Device plugs, cbaf is loaded, notifications happen.
32 *
33 * 2. The connection manager (CM) sees a device with CBAF capability
34 * (the wusb_chid etc. files in /sys/devices/blah/OURDEVICE).
35 *
36 * 3. The CM writes the host name, supported band groups, and the CHID
37 * (host ID) into the wusb_host_name, wusb_host_band_groups and
38 * wusb_chid files. These get sent to the device and the CDID (if
39 * any) for this host is requested.
40 *
41 * 4. The CM can verify that the device's supported band groups
42 * (wusb_device_band_groups) are compatible with the host.
43 *
44 * 5. The CM reads the wusb_cdid file.
45 *
46 * 6. The CM looks up its database
47 *
48 * 6.1 If it has a matching CHID,CDID entry, the device has been
49 * authorized before (paired) and nothing further needs to be
50 * done.
51 *
52 * 6.2 If the CDID is zero (or the CM doesn't find a matching CDID in
53 * its database), the device is assumed to be not known. The CM
54 * may associate the host with device by: writing a randomly
55 * generated CDID to wusb_cdid and then a random CK to wusb_ck
56 * (this uploads the new CC to the device).
57 *
58 * CMD may choose to prompt the user before associating with a new
59 * device.
60 *
61 * 7. Device is unplugged.
62 *
63 * When the device tries to connect wirelessly, it will present its
64 * CDID to the WUSB host controller. The CM will query the
65 * database. If the CHID/CDID pair found, it will (with a 4-way
66 * handshake) challenge the device to demonstrate it has the CK secret
67 * key (from our database) without actually exchanging it. Once
68 * satisfied, crypto keys are derived from the CK, the device is
69 * connected and all communication is encrypted.
70 *
71 * References:
72 * [WUSB-AM] Association Models Supplement to the Certified Wireless
73 * Universal Serial Bus Specification, version 1.0.
74 */
75#include <linux/module.h>
76#include <linux/ctype.h>
77#include <linux/usb.h>
78#include <linux/interrupt.h>
79#include <linux/delay.h>
80#include <linux/random.h>
81#include <linux/slab.h>
82#include <linux/mutex.h>
83#include <linux/uwb.h>
84#include <linux/usb/wusb.h>
85#include <linux/usb/association.h>
86
87#define CBA_NAME_LEN 0x40 /* [WUSB-AM] table 4-7 */
88
89/* An instance of a Cable-Based-Association-Framework device */
90struct cbaf {
91 struct usb_device *usb_dev;
92 struct usb_interface *usb_iface;
93 void *buffer;
94 size_t buffer_size;
95
96 struct wusb_ckhdid chid;
97 char host_name[CBA_NAME_LEN];
98 u16 host_band_groups;
99
100 struct wusb_ckhdid cdid;
101 char device_name[CBA_NAME_LEN];
102 u16 device_band_groups;
103
104 struct wusb_ckhdid ck;
105};
106
107/*
108 * Verify that a CBAF USB-interface has what we need
109 *
110 * According to [WUSB-AM], CBA devices should provide at least two
111 * interfaces:
112 * - RETRIEVE_HOST_INFO
113 * - ASSOCIATE
114 *
115 * If the device doesn't provide these interfaces, we do not know how
116 * to deal with it.
117 */
118static int cbaf_check(struct cbaf *cbaf)
119{
120 int result;
121 struct device *dev = &cbaf->usb_iface->dev;
122 struct wusb_cbaf_assoc_info *assoc_info;
123 struct wusb_cbaf_assoc_request *assoc_request;
124 size_t assoc_size;
125 void *itr, *top;
126 int ar_rhi = 0, ar_assoc = 0;
127
128 result = usb_control_msg(
129 cbaf->usb_dev, usb_rcvctrlpipe(cbaf->usb_dev, 0),
130 CBAF_REQ_GET_ASSOCIATION_INFORMATION,
131 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
132 0, cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
133 cbaf->buffer, cbaf->buffer_size, USB_CTRL_GET_TIMEOUT);
134 if (result < 0) {
135 dev_err(dev, "Cannot get available association types: %d\n",
136 result);
137 return result;
138 }
139
140 assoc_info = cbaf->buffer;
141 if (result < sizeof(*assoc_info)) {
142 dev_err(dev, "Not enough data to decode association info "
143 "header (%zu vs %zu bytes required)\n",
144 (size_t)result, sizeof(*assoc_info));
145 return result;
146 }
147
148 assoc_size = le16_to_cpu(assoc_info->Length);
149 if (result < assoc_size) {
150 dev_err(dev, "Not enough data to decode association info "
151 "(%zu vs %zu bytes required)\n",
152 (size_t)assoc_size, sizeof(*assoc_info));
153 return result;
154 }
155 /*
156 * From now on, we just verify, but won't error out unless we
157 * don't find the AR_TYPE_WUSB_{RETRIEVE_HOST_INFO,ASSOCIATE}
158 * types.
159 */
160 itr = cbaf->buffer + sizeof(*assoc_info);
161 top = cbaf->buffer + assoc_size;
162 dev_dbg(dev, "Found %u association requests (%zu bytes)\n",
163 assoc_info->NumAssociationRequests, assoc_size);
164
165 while (itr < top) {
166 u16 ar_type, ar_subtype;
167 u32 ar_size;
168 const char *ar_name;
169
170 assoc_request = itr;
171
172 if (top - itr < sizeof(*assoc_request)) {
173 dev_err(dev, "Not enough data to decode association "
174 "request (%zu vs %zu bytes needed)\n",
175 top - itr, sizeof(*assoc_request));
176 break;
177 }
178
179 ar_type = le16_to_cpu(assoc_request->AssociationTypeId);
180 ar_subtype = le16_to_cpu(assoc_request->AssociationSubTypeId);
181 ar_size = le32_to_cpu(assoc_request->AssociationTypeInfoSize);
182 ar_name = "unknown";
183
184 switch (ar_type) {
185 case AR_TYPE_WUSB:
186 /* Verify we have what is mandated by [WUSB-AM]. */
187 switch (ar_subtype) {
188 case AR_TYPE_WUSB_RETRIEVE_HOST_INFO:
189 ar_name = "RETRIEVE_HOST_INFO";
190 ar_rhi = 1;
191 break;
192 case AR_TYPE_WUSB_ASSOCIATE:
193 /* send assoc data */
194 ar_name = "ASSOCIATE";
195 ar_assoc = 1;
196 break;
197 }
198 break;
199 }
200
201 dev_dbg(dev, "Association request #%02u: 0x%04x/%04x "
202 "(%zu bytes): %s\n",
203 assoc_request->AssociationDataIndex, ar_type,
204 ar_subtype, (size_t)ar_size, ar_name);
205
206 itr += sizeof(*assoc_request);
207 }
208
209 if (!ar_rhi) {
210 dev_err(dev, "Missing RETRIEVE_HOST_INFO association "
211 "request\n");
212 return -EINVAL;
213 }
214 if (!ar_assoc) {
215 dev_err(dev, "Missing ASSOCIATE association request\n");
216 return -EINVAL;
217 }
218
219 return 0;
220}
221
222static const struct wusb_cbaf_host_info cbaf_host_info_defaults = {
223 .AssociationTypeId_hdr = WUSB_AR_AssociationTypeId,
224 .AssociationTypeId = cpu_to_le16(AR_TYPE_WUSB),
225 .AssociationSubTypeId_hdr = WUSB_AR_AssociationSubTypeId,
226 .AssociationSubTypeId = cpu_to_le16(AR_TYPE_WUSB_RETRIEVE_HOST_INFO),
227 .CHID_hdr = WUSB_AR_CHID,
228 .LangID_hdr = WUSB_AR_LangID,
229 .HostFriendlyName_hdr = WUSB_AR_HostFriendlyName,
230};
231
232/* Send WUSB host information (CHID and name) to a CBAF device */
233static int cbaf_send_host_info(struct cbaf *cbaf)
234{
235 struct wusb_cbaf_host_info *hi;
236 size_t name_len;
237 size_t hi_size;
238
239 hi = cbaf->buffer;
240 memset(hi, 0, sizeof(*hi));
241 *hi = cbaf_host_info_defaults;
242 hi->CHID = cbaf->chid;
243 hi->LangID = 0; /* FIXME: I guess... */
244 strlcpy(hi->HostFriendlyName, cbaf->host_name, CBA_NAME_LEN);
245 name_len = strlen(cbaf->host_name);
246 hi->HostFriendlyName_hdr.len = cpu_to_le16(name_len);
247 hi_size = sizeof(*hi) + name_len;
248
249 return usb_control_msg(cbaf->usb_dev,
250 usb_sndctrlpipe(cbaf->usb_dev, 0),
251 CBAF_REQ_SET_ASSOCIATION_RESPONSE,
252 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
253 0x0101,
254 cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
255 hi, hi_size, USB_CTRL_SET_TIMEOUT);
256}
257
258/*
259 * Get device's information (CDID) associated to CHID
260 *
261 * The device will return it's information (CDID, name, bandgroups)
262 * associated to the CHID we have set before, or 0 CDID and default
263 * name and bandgroup if no CHID set or unknown.
264 */
265static int cbaf_cdid_get(struct cbaf *cbaf)
266{
267 int result;
268 struct device *dev = &cbaf->usb_iface->dev;
269 struct wusb_cbaf_device_info *di;
270 size_t needed;
271
272 di = cbaf->buffer;
273 result = usb_control_msg(
274 cbaf->usb_dev, usb_rcvctrlpipe(cbaf->usb_dev, 0),
275 CBAF_REQ_GET_ASSOCIATION_REQUEST,
276 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
277 0x0200, cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
278 di, cbaf->buffer_size, USB_CTRL_GET_TIMEOUT);
279 if (result < 0) {
280 dev_err(dev, "Cannot request device information: %d\n",
281 result);
282 return result;
283 }
284
285 needed = result < sizeof(*di) ? sizeof(*di) : le32_to_cpu(di->Length);
286 if (result < needed) {
287 dev_err(dev, "Not enough data in DEVICE_INFO reply (%zu vs "
288 "%zu bytes needed)\n", (size_t)result, needed);
289 return -ENOENT;
290 }
291
292 strlcpy(cbaf->device_name, di->DeviceFriendlyName, CBA_NAME_LEN);
293 cbaf->cdid = di->CDID;
294 cbaf->device_band_groups = le16_to_cpu(di->BandGroups);
295
296 return 0;
297}
298
299static ssize_t cbaf_wusb_chid_show(struct device *dev,
300 struct device_attribute *attr,
301 char *buf)
302{
303 struct usb_interface *iface = to_usb_interface(dev);
304 struct cbaf *cbaf = usb_get_intfdata(iface);
305 char pr_chid[WUSB_CKHDID_STRSIZE];
306
307 ckhdid_printf(pr_chid, sizeof(pr_chid), &cbaf->chid);
308 return scnprintf(buf, PAGE_SIZE, "%s\n", pr_chid);
309}
310
311static ssize_t cbaf_wusb_chid_store(struct device *dev,
312 struct device_attribute *attr,
313 const char *buf, size_t size)
314{
315 ssize_t result;
316 struct usb_interface *iface = to_usb_interface(dev);
317 struct cbaf *cbaf = usb_get_intfdata(iface);
318
319 result = sscanf(buf,
320 "%02hhx %02hhx %02hhx %02hhx "
321 "%02hhx %02hhx %02hhx %02hhx "
322 "%02hhx %02hhx %02hhx %02hhx "
323 "%02hhx %02hhx %02hhx %02hhx",
324 &cbaf->chid.data[0] , &cbaf->chid.data[1],
325 &cbaf->chid.data[2] , &cbaf->chid.data[3],
326 &cbaf->chid.data[4] , &cbaf->chid.data[5],
327 &cbaf->chid.data[6] , &cbaf->chid.data[7],
328 &cbaf->chid.data[8] , &cbaf->chid.data[9],
329 &cbaf->chid.data[10], &cbaf->chid.data[11],
330 &cbaf->chid.data[12], &cbaf->chid.data[13],
331 &cbaf->chid.data[14], &cbaf->chid.data[15]);
332
333 if (result != 16)
334 return -EINVAL;
335
336 result = cbaf_send_host_info(cbaf);
337 if (result < 0)
338 return result;
339 result = cbaf_cdid_get(cbaf);
340 if (result < 0)
341 return result;
342 return size;
343}
344static DEVICE_ATTR(wusb_chid, 0600, cbaf_wusb_chid_show, cbaf_wusb_chid_store);
345
346static ssize_t cbaf_wusb_host_name_show(struct device *dev,
347 struct device_attribute *attr,
348 char *buf)
349{
350 struct usb_interface *iface = to_usb_interface(dev);
351 struct cbaf *cbaf = usb_get_intfdata(iface);
352
353 return scnprintf(buf, PAGE_SIZE, "%s\n", cbaf->host_name);
354}
355
356static ssize_t cbaf_wusb_host_name_store(struct device *dev,
357 struct device_attribute *attr,
358 const char *buf, size_t size)
359{
360 ssize_t result;
361 struct usb_interface *iface = to_usb_interface(dev);
362 struct cbaf *cbaf = usb_get_intfdata(iface);
363
364 result = sscanf(buf, "%63s", cbaf->host_name);
365 if (result != 1)
366 return -EINVAL;
367
368 return size;
369}
370static DEVICE_ATTR(wusb_host_name, 0600, cbaf_wusb_host_name_show,
371 cbaf_wusb_host_name_store);
372
373static ssize_t cbaf_wusb_host_band_groups_show(struct device *dev,
374 struct device_attribute *attr,
375 char *buf)
376{
377 struct usb_interface *iface = to_usb_interface(dev);
378 struct cbaf *cbaf = usb_get_intfdata(iface);
379
380 return scnprintf(buf, PAGE_SIZE, "0x%04x\n", cbaf->host_band_groups);
381}
382
383static ssize_t cbaf_wusb_host_band_groups_store(struct device *dev,
384 struct device_attribute *attr,
385 const char *buf, size_t size)
386{
387 ssize_t result;
388 struct usb_interface *iface = to_usb_interface(dev);
389 struct cbaf *cbaf = usb_get_intfdata(iface);
390 u16 band_groups = 0;
391
392 result = sscanf(buf, "%04hx", &band_groups);
393 if (result != 1)
394 return -EINVAL;
395
396 cbaf->host_band_groups = band_groups;
397
398 return size;
399}
400
401static DEVICE_ATTR(wusb_host_band_groups, 0600,
402 cbaf_wusb_host_band_groups_show,
403 cbaf_wusb_host_band_groups_store);
404
405static const struct wusb_cbaf_device_info cbaf_device_info_defaults = {
406 .Length_hdr = WUSB_AR_Length,
407 .CDID_hdr = WUSB_AR_CDID,
408 .BandGroups_hdr = WUSB_AR_BandGroups,
409 .LangID_hdr = WUSB_AR_LangID,
410 .DeviceFriendlyName_hdr = WUSB_AR_DeviceFriendlyName,
411};
412
413static ssize_t cbaf_wusb_cdid_show(struct device *dev,
414 struct device_attribute *attr, char *buf)
415{
416 struct usb_interface *iface = to_usb_interface(dev);
417 struct cbaf *cbaf = usb_get_intfdata(iface);
418 char pr_cdid[WUSB_CKHDID_STRSIZE];
419
420 ckhdid_printf(pr_cdid, sizeof(pr_cdid), &cbaf->cdid);
421 return scnprintf(buf, PAGE_SIZE, "%s\n", pr_cdid);
422}
423
424static ssize_t cbaf_wusb_cdid_store(struct device *dev,
425 struct device_attribute *attr,
426 const char *buf, size_t size)
427{
428 ssize_t result;
429 struct usb_interface *iface = to_usb_interface(dev);
430 struct cbaf *cbaf = usb_get_intfdata(iface);
431 struct wusb_ckhdid cdid;
432
433 result = sscanf(buf,
434 "%02hhx %02hhx %02hhx %02hhx "
435 "%02hhx %02hhx %02hhx %02hhx "
436 "%02hhx %02hhx %02hhx %02hhx "
437 "%02hhx %02hhx %02hhx %02hhx",
438 &cdid.data[0] , &cdid.data[1],
439 &cdid.data[2] , &cdid.data[3],
440 &cdid.data[4] , &cdid.data[5],
441 &cdid.data[6] , &cdid.data[7],
442 &cdid.data[8] , &cdid.data[9],
443 &cdid.data[10], &cdid.data[11],
444 &cdid.data[12], &cdid.data[13],
445 &cdid.data[14], &cdid.data[15]);
446 if (result != 16)
447 return -EINVAL;
448
449 cbaf->cdid = cdid;
450
451 return size;
452}
453static DEVICE_ATTR(wusb_cdid, 0600, cbaf_wusb_cdid_show, cbaf_wusb_cdid_store);
454
455static ssize_t cbaf_wusb_device_band_groups_show(struct device *dev,
456 struct device_attribute *attr,
457 char *buf)
458{
459 struct usb_interface *iface = to_usb_interface(dev);
460 struct cbaf *cbaf = usb_get_intfdata(iface);
461
462 return scnprintf(buf, PAGE_SIZE, "0x%04x\n", cbaf->device_band_groups);
463}
464
465static DEVICE_ATTR(wusb_device_band_groups, 0600,
466 cbaf_wusb_device_band_groups_show,
467 NULL);
468
469static ssize_t cbaf_wusb_device_name_show(struct device *dev,
470 struct device_attribute *attr,
471 char *buf)
472{
473 struct usb_interface *iface = to_usb_interface(dev);
474 struct cbaf *cbaf = usb_get_intfdata(iface);
475
476 return scnprintf(buf, PAGE_SIZE, "%s\n", cbaf->device_name);
477}
478static DEVICE_ATTR(wusb_device_name, 0600, cbaf_wusb_device_name_show, NULL);
479
480static const struct wusb_cbaf_cc_data cbaf_cc_data_defaults = {
481 .AssociationTypeId_hdr = WUSB_AR_AssociationTypeId,
482 .AssociationTypeId = cpu_to_le16(AR_TYPE_WUSB),
483 .AssociationSubTypeId_hdr = WUSB_AR_AssociationSubTypeId,
484 .AssociationSubTypeId = cpu_to_le16(AR_TYPE_WUSB_ASSOCIATE),
485 .Length_hdr = WUSB_AR_Length,
486 .Length = cpu_to_le32(sizeof(struct wusb_cbaf_cc_data)),
487 .ConnectionContext_hdr = WUSB_AR_ConnectionContext,
488 .BandGroups_hdr = WUSB_AR_BandGroups,
489};
490
491static const struct wusb_cbaf_cc_data_fail cbaf_cc_data_fail_defaults = {
492 .AssociationTypeId_hdr = WUSB_AR_AssociationTypeId,
493 .AssociationSubTypeId_hdr = WUSB_AR_AssociationSubTypeId,
494 .Length_hdr = WUSB_AR_Length,
495 .AssociationStatus_hdr = WUSB_AR_AssociationStatus,
496};
497
498/*
499 * Send a new CC to the device.
500 */
501static int cbaf_cc_upload(struct cbaf *cbaf)
502{
503 int result;
504 struct device *dev = &cbaf->usb_iface->dev;
505 struct wusb_cbaf_cc_data *ccd;
506 char pr_cdid[WUSB_CKHDID_STRSIZE];
507
508 ccd = cbaf->buffer;
509 *ccd = cbaf_cc_data_defaults;
510 ccd->CHID = cbaf->chid;
511 ccd->CDID = cbaf->cdid;
512 ccd->CK = cbaf->ck;
513 ccd->BandGroups = cpu_to_le16(cbaf->host_band_groups);
514
515 dev_dbg(dev, "Trying to upload CC:\n");
516 ckhdid_printf(pr_cdid, sizeof(pr_cdid), &ccd->CHID);
517 dev_dbg(dev, " CHID %s\n", pr_cdid);
518 ckhdid_printf(pr_cdid, sizeof(pr_cdid), &ccd->CDID);
519 dev_dbg(dev, " CDID %s\n", pr_cdid);
520 dev_dbg(dev, " Bandgroups 0x%04x\n", cbaf->host_band_groups);
521
522 result = usb_control_msg(
523 cbaf->usb_dev, usb_sndctrlpipe(cbaf->usb_dev, 0),
524 CBAF_REQ_SET_ASSOCIATION_RESPONSE,
525 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
526 0x0201, cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
527 ccd, sizeof(*ccd), USB_CTRL_SET_TIMEOUT);
528
529 return result;
530}
531
532static ssize_t cbaf_wusb_ck_store(struct device *dev,
533 struct device_attribute *attr,
534 const char *buf, size_t size)
535{
536 ssize_t result;
537 struct usb_interface *iface = to_usb_interface(dev);
538 struct cbaf *cbaf = usb_get_intfdata(iface);
539
540 result = sscanf(buf,
541 "%02hhx %02hhx %02hhx %02hhx "
542 "%02hhx %02hhx %02hhx %02hhx "
543 "%02hhx %02hhx %02hhx %02hhx "
544 "%02hhx %02hhx %02hhx %02hhx",
545 &cbaf->ck.data[0] , &cbaf->ck.data[1],
546 &cbaf->ck.data[2] , &cbaf->ck.data[3],
547 &cbaf->ck.data[4] , &cbaf->ck.data[5],
548 &cbaf->ck.data[6] , &cbaf->ck.data[7],
549 &cbaf->ck.data[8] , &cbaf->ck.data[9],
550 &cbaf->ck.data[10], &cbaf->ck.data[11],
551 &cbaf->ck.data[12], &cbaf->ck.data[13],
552 &cbaf->ck.data[14], &cbaf->ck.data[15]);
553 if (result != 16)
554 return -EINVAL;
555
556 result = cbaf_cc_upload(cbaf);
557 if (result < 0)
558 return result;
559
560 return size;
561}
562static DEVICE_ATTR(wusb_ck, 0600, NULL, cbaf_wusb_ck_store);
563
564static struct attribute *cbaf_dev_attrs[] = {
565 &dev_attr_wusb_host_name.attr,
566 &dev_attr_wusb_host_band_groups.attr,
567 &dev_attr_wusb_chid.attr,
568 &dev_attr_wusb_cdid.attr,
569 &dev_attr_wusb_device_name.attr,
570 &dev_attr_wusb_device_band_groups.attr,
571 &dev_attr_wusb_ck.attr,
572 NULL,
573};
574
575static const struct attribute_group cbaf_dev_attr_group = {
576 .name = NULL, /* we want them in the same directory */
577 .attrs = cbaf_dev_attrs,
578};
579
580static int cbaf_probe(struct usb_interface *iface,
581 const struct usb_device_id *id)
582{
583 struct cbaf *cbaf;
584 struct device *dev = &iface->dev;
585 int result = -ENOMEM;
586
587 cbaf = kzalloc(sizeof(*cbaf), GFP_KERNEL);
588 if (cbaf == NULL)
589 goto error_kzalloc;
590 cbaf->buffer = kmalloc(512, GFP_KERNEL);
591 if (cbaf->buffer == NULL)
592 goto error_kmalloc_buffer;
593
594 cbaf->buffer_size = 512;
595 cbaf->usb_dev = usb_get_dev(interface_to_usbdev(iface));
596 cbaf->usb_iface = usb_get_intf(iface);
597 result = cbaf_check(cbaf);
598 if (result < 0) {
599 dev_err(dev, "This device is not WUSB-CBAF compliant and is not supported yet.\n");
600 goto error_check;
601 }
602
603 result = sysfs_create_group(&dev->kobj, &cbaf_dev_attr_group);
604 if (result < 0) {
605 dev_err(dev, "Can't register sysfs attr group: %d\n", result);
606 goto error_create_group;
607 }
608 usb_set_intfdata(iface, cbaf);
609 return 0;
610
611error_create_group:
612error_check:
613 usb_put_intf(iface);
614 usb_put_dev(cbaf->usb_dev);
615 kfree(cbaf->buffer);
616error_kmalloc_buffer:
617 kfree(cbaf);
618error_kzalloc:
619 return result;
620}
621
622static void cbaf_disconnect(struct usb_interface *iface)
623{
624 struct cbaf *cbaf = usb_get_intfdata(iface);
625 struct device *dev = &iface->dev;
626 sysfs_remove_group(&dev->kobj, &cbaf_dev_attr_group);
627 usb_set_intfdata(iface, NULL);
628 usb_put_intf(iface);
629 usb_put_dev(cbaf->usb_dev);
630 kfree(cbaf->buffer);
631 /* paranoia: clean up crypto keys */
632 kzfree(cbaf);
633}
634
635static const struct usb_device_id cbaf_id_table[] = {
636 { USB_INTERFACE_INFO(0xef, 0x03, 0x01), },
637 { },
638};
639MODULE_DEVICE_TABLE(usb, cbaf_id_table);
640
641static struct usb_driver cbaf_driver = {
642 .name = "wusb-cbaf",
643 .id_table = cbaf_id_table,
644 .probe = cbaf_probe,
645 .disconnect = cbaf_disconnect,
646};
647
648module_usb_driver(cbaf_driver);
649
650MODULE_AUTHOR("Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>");
651MODULE_DESCRIPTION("Wireless USB Cable Based Association");
652MODULE_LICENSE("GPL");