Merge branch 'drm-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied...
[linux-2.6] / drivers / usb / wusbcore / cbaf.c
1 /*
2  * Wireless USB - Cable Based Association
3  *
4  *
5  * Copyright (C) 2006 Intel Corporation
6  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
7  * Copyright (C) 2008 Cambridge Silicon Radio Ltd.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License version
11  * 2 as published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
21  * 02110-1301, USA.
22  *
23  *
24  * WUSB devices have to be paired (associated in WUSB lingo) so
25  * that they can connect to the system.
26  *
27  * One way of pairing is using CBA-Cable Based Association. First
28  * time you plug the device with a cable, association is done between
29  * host and device and subsequent times, you can connect wirelessly
30  * without having to associate again. That's the idea.
31  *
32  * This driver does nothing Earth shattering. It just provides an
33  * interface to chat with the wire-connected device so we can get a
34  * CDID (device ID) that might have been previously associated to a
35  * CHID (host ID) and to set up a new <CHID,CDID,CK> triplet
36  * (connection context), with the CK being the secret, or connection
37  * key. This is the pairing data.
38  *
39  * When a device with the CBA capability connects, the probe routine
40  * just creates a bunch of sysfs files that a user space enumeration
41  * manager uses to allow it to connect wirelessly to the system or not.
42  *
43  * The process goes like this:
44  *
45  * 1. Device plugs, cbaf is loaded, notifications happen.
46  *
47  * 2. The connection manager (CM) sees a device with CBAF capability
48  *    (the wusb_chid etc. files in /sys/devices/blah/OURDEVICE).
49  *
50  * 3. The CM writes the host name, supported band groups, and the CHID
51  *    (host ID) into the wusb_host_name, wusb_host_band_groups and
52  *    wusb_chid files. These get sent to the device and the CDID (if
53  *    any) for this host is requested.
54  *
55  * 4. The CM can verify that the device's supported band groups
56  *    (wusb_device_band_groups) are compatible with the host.
57  *
58  * 5. The CM reads the wusb_cdid file.
59  *
60  * 6. The CM looks up its database
61  *
62  * 6.1 If it has a matching CHID,CDID entry, the device has been
63  *     authorized before (paired) and nothing further needs to be
64  *     done.
65  *
66  * 6.2 If the CDID is zero (or the CM doesn't find a matching CDID in
67  *     its database), the device is assumed to be not known.  The CM
68  *     may associate the host with device by: writing a randomly
69  *     generated CDID to wusb_cdid and then a random CK to wusb_ck
70  *     (this uploads the new CC to the device).
71  *
72  *     CMD may choose to prompt the user before associating with a new
73  *     device.
74  *
75  * 7. Device is unplugged.
76  *
77  * When the device tries to connect wirelessly, it will present its
78  * CDID to the WUSB host controller.  The CM will query the
79  * database. If the CHID/CDID pair found, it will (with a 4-way
80  * handshake) challenge the device to demonstrate it has the CK secret
81  * key (from our database) without actually exchanging it. Once
82  * satisfied, crypto keys are derived from the CK, the device is
83  * connected and all communication is encrypted.
84  *
85  * References:
86  *   [WUSB-AM] Association Models Supplement to the Certified Wireless
87  *             Universal Serial Bus Specification, version 1.0.
88  */
89 #include <linux/module.h>
90 #include <linux/ctype.h>
91 #include <linux/version.h>
92 #include <linux/usb.h>
93 #include <linux/interrupt.h>
94 #include <linux/delay.h>
95 #include <linux/random.h>
96 #include <linux/mutex.h>
97 #include <linux/uwb.h>
98 #include <linux/usb/wusb.h>
99 #include <linux/usb/association.h>
100
101 #define CBA_NAME_LEN 0x40 /* [WUSB-AM] table 4-7 */
102
103 /* An instance of a Cable-Based-Association-Framework device */
104 struct cbaf {
105         struct usb_device *usb_dev;
106         struct usb_interface *usb_iface;
107         void *buffer;
108         size_t buffer_size;
109
110         struct wusb_ckhdid chid;
111         char host_name[CBA_NAME_LEN];
112         u16 host_band_groups;
113
114         struct wusb_ckhdid cdid;
115         char device_name[CBA_NAME_LEN];
116         u16 device_band_groups;
117
118         struct wusb_ckhdid ck;
119 };
120
121 /*
122  * Verify that a CBAF USB-interface has what we need
123  *
124  * According to [WUSB-AM], CBA devices should provide at least two
125  * interfaces:
126  *  - RETRIEVE_HOST_INFO
127  *  - ASSOCIATE
128  *
129  * If the device doesn't provide these interfaces, we do not know how
130  * to deal with it.
131  */
132 static int cbaf_check(struct cbaf *cbaf)
133 {
134         int result;
135         struct device *dev = &cbaf->usb_iface->dev;
136         struct wusb_cbaf_assoc_info *assoc_info;
137         struct wusb_cbaf_assoc_request *assoc_request;
138         size_t assoc_size;
139         void *itr, *top;
140         int ar_rhi = 0, ar_assoc = 0;
141
142         result = usb_control_msg(
143                 cbaf->usb_dev, usb_rcvctrlpipe(cbaf->usb_dev, 0),
144                 CBAF_REQ_GET_ASSOCIATION_INFORMATION,
145                 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
146                 0, cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
147                 cbaf->buffer, cbaf->buffer_size, 1000 /* FIXME: arbitrary */);
148         if (result < 0) {
149                 dev_err(dev, "Cannot get available association types: %d\n",
150                         result);
151                 return result;
152         }
153
154         assoc_info = cbaf->buffer;
155         if (result < sizeof(*assoc_info)) {
156                 dev_err(dev, "Not enough data to decode association info "
157                         "header (%zu vs %zu bytes required)\n",
158                         (size_t)result, sizeof(*assoc_info));
159                 return result;
160         }
161
162         assoc_size = le16_to_cpu(assoc_info->Length);
163         if (result < assoc_size) {
164                 dev_err(dev, "Not enough data to decode association info "
165                         "(%zu vs %zu bytes required)\n",
166                         (size_t)assoc_size, sizeof(*assoc_info));
167                 return result;
168         }
169         /*
170          * From now on, we just verify, but won't error out unless we
171          * don't find the AR_TYPE_WUSB_{RETRIEVE_HOST_INFO,ASSOCIATE}
172          * types.
173          */
174         itr = cbaf->buffer + sizeof(*assoc_info);
175         top = cbaf->buffer + assoc_size;
176         dev_dbg(dev, "Found %u association requests (%zu bytes)\n",
177                  assoc_info->NumAssociationRequests, assoc_size);
178
179         while (itr < top) {
180                 u16 ar_type, ar_subtype;
181                 u32 ar_size;
182                 const char *ar_name;
183
184                 assoc_request = itr;
185
186                 if (top - itr < sizeof(*assoc_request)) {
187                         dev_err(dev, "Not enough data to decode associaton "
188                                 "request (%zu vs %zu bytes needed)\n",
189                                 top - itr, sizeof(*assoc_request));
190                         break;
191                 }
192
193                 ar_type = le16_to_cpu(assoc_request->AssociationTypeId);
194                 ar_subtype = le16_to_cpu(assoc_request->AssociationSubTypeId);
195                 ar_size = le32_to_cpu(assoc_request->AssociationTypeInfoSize);
196                 ar_name = "unknown";
197
198                 switch (ar_type) {
199                 case AR_TYPE_WUSB:
200                         /* Verify we have what is mandated by [WUSB-AM]. */
201                         switch (ar_subtype) {
202                         case AR_TYPE_WUSB_RETRIEVE_HOST_INFO:
203                                 ar_name = "RETRIEVE_HOST_INFO";
204                                 ar_rhi = 1;
205                                 break;
206                         case AR_TYPE_WUSB_ASSOCIATE:
207                                 /* send assoc data */
208                                 ar_name = "ASSOCIATE";
209                                 ar_assoc = 1;
210                                 break;
211                         };
212                         break;
213                 };
214
215                 dev_dbg(dev, "Association request #%02u: 0x%04x/%04x "
216                          "(%zu bytes): %s\n",
217                          assoc_request->AssociationDataIndex, ar_type,
218                          ar_subtype, (size_t)ar_size, ar_name);
219
220                 itr += sizeof(*assoc_request);
221         }
222
223         if (!ar_rhi) {
224                 dev_err(dev, "Missing RETRIEVE_HOST_INFO association "
225                         "request\n");
226                 return -EINVAL;
227         }
228         if (!ar_assoc) {
229                 dev_err(dev, "Missing ASSOCIATE association request\n");
230                 return -EINVAL;
231         }
232
233         return 0;
234 }
235
236 static const struct wusb_cbaf_host_info cbaf_host_info_defaults = {
237         .AssociationTypeId_hdr    = WUSB_AR_AssociationTypeId,
238         .AssociationTypeId        = cpu_to_le16(AR_TYPE_WUSB),
239         .AssociationSubTypeId_hdr = WUSB_AR_AssociationSubTypeId,
240         .AssociationSubTypeId = cpu_to_le16(AR_TYPE_WUSB_RETRIEVE_HOST_INFO),
241         .CHID_hdr                 = WUSB_AR_CHID,
242         .LangID_hdr               = WUSB_AR_LangID,
243         .HostFriendlyName_hdr     = WUSB_AR_HostFriendlyName,
244 };
245
246 /* Send WUSB host information (CHID and name) to a CBAF device */
247 static int cbaf_send_host_info(struct cbaf *cbaf)
248 {
249         struct wusb_cbaf_host_info *hi;
250         size_t name_len;
251         size_t hi_size;
252
253         hi = cbaf->buffer;
254         memset(hi, 0, sizeof(*hi));
255         *hi = cbaf_host_info_defaults;
256         hi->CHID = cbaf->chid;
257         hi->LangID = 0; /* FIXME: I guess... */
258         strlcpy(hi->HostFriendlyName, cbaf->host_name, CBA_NAME_LEN);
259         name_len = strlen(cbaf->host_name);
260         hi->HostFriendlyName_hdr.len = cpu_to_le16(name_len);
261         hi_size = sizeof(*hi) + name_len;
262
263         return usb_control_msg(cbaf->usb_dev, usb_sndctrlpipe(cbaf->usb_dev, 0),
264                         CBAF_REQ_SET_ASSOCIATION_RESPONSE,
265                         USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
266                         0x0101,
267                         cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
268                         hi, hi_size, 1000 /* FIXME: arbitrary */);
269 }
270
271 /*
272  * Get device's information (CDID) associated to CHID
273  *
274  * The device will return it's information (CDID, name, bandgroups)
275  * associated to the CHID we have set before, or 0 CDID and default
276  * name and bandgroup if no CHID set or unknown.
277  */
278 static int cbaf_cdid_get(struct cbaf *cbaf)
279 {
280         int result;
281         struct device *dev = &cbaf->usb_iface->dev;
282         struct wusb_cbaf_device_info *di;
283         size_t needed;
284
285         di = cbaf->buffer;
286         result = usb_control_msg(
287                 cbaf->usb_dev, usb_rcvctrlpipe(cbaf->usb_dev, 0),
288                 CBAF_REQ_GET_ASSOCIATION_REQUEST,
289                 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
290                 0x0200, cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
291                 di, cbaf->buffer_size, 1000 /* FIXME: arbitrary */);
292         if (result < 0) {
293                 dev_err(dev, "Cannot request device information: %d\n", result);
294                 return result;
295         }
296
297         needed = result < sizeof(*di) ? sizeof(*di) : le32_to_cpu(di->Length);
298         if (result < needed) {
299                 dev_err(dev, "Not enough data in DEVICE_INFO reply (%zu vs "
300                         "%zu bytes needed)\n", (size_t)result, needed);
301                 return result;
302         }
303
304         strlcpy(cbaf->device_name, di->DeviceFriendlyName, CBA_NAME_LEN);
305         cbaf->cdid = di->CDID;
306         cbaf->device_band_groups = le16_to_cpu(di->BandGroups);
307
308         return 0;
309 }
310
311 static ssize_t cbaf_wusb_chid_show(struct device *dev,
312                                         struct device_attribute *attr,
313                                         char *buf)
314 {
315         struct usb_interface *iface = to_usb_interface(dev);
316         struct cbaf *cbaf = usb_get_intfdata(iface);
317         char pr_chid[WUSB_CKHDID_STRSIZE];
318
319         ckhdid_printf(pr_chid, sizeof(pr_chid), &cbaf->chid);
320         return scnprintf(buf, PAGE_SIZE, "%s\n", pr_chid);
321 }
322
323 static ssize_t cbaf_wusb_chid_store(struct device *dev,
324                                          struct device_attribute *attr,
325                                          const char *buf, size_t size)
326 {
327         ssize_t result;
328         struct usb_interface *iface = to_usb_interface(dev);
329         struct cbaf *cbaf = usb_get_intfdata(iface);
330
331         result = sscanf(buf,
332                         "%02hhx %02hhx %02hhx %02hhx "
333                         "%02hhx %02hhx %02hhx %02hhx "
334                         "%02hhx %02hhx %02hhx %02hhx "
335                         "%02hhx %02hhx %02hhx %02hhx",
336                         &cbaf->chid.data[0] , &cbaf->chid.data[1],
337                         &cbaf->chid.data[2] , &cbaf->chid.data[3],
338                         &cbaf->chid.data[4] , &cbaf->chid.data[5],
339                         &cbaf->chid.data[6] , &cbaf->chid.data[7],
340                         &cbaf->chid.data[8] , &cbaf->chid.data[9],
341                         &cbaf->chid.data[10], &cbaf->chid.data[11],
342                         &cbaf->chid.data[12], &cbaf->chid.data[13],
343                         &cbaf->chid.data[14], &cbaf->chid.data[15]);
344
345         if (result != 16)
346                 return -EINVAL;
347
348         result = cbaf_send_host_info(cbaf);
349         if (result < 0)
350                 return result;
351         result = cbaf_cdid_get(cbaf);
352         if (result < 0)
353                 return -result;
354         return size;
355 }
356 static DEVICE_ATTR(wusb_chid, 0600, cbaf_wusb_chid_show, cbaf_wusb_chid_store);
357
358 static ssize_t cbaf_wusb_host_name_show(struct device *dev,
359                                         struct device_attribute *attr,
360                                         char *buf)
361 {
362         struct usb_interface *iface = to_usb_interface(dev);
363         struct cbaf *cbaf = usb_get_intfdata(iface);
364
365         return scnprintf(buf, PAGE_SIZE, "%s\n", cbaf->host_name);
366 }
367
368 static ssize_t cbaf_wusb_host_name_store(struct device *dev,
369                                          struct device_attribute *attr,
370                                          const char *buf, size_t size)
371 {
372         ssize_t result;
373         struct usb_interface *iface = to_usb_interface(dev);
374         struct cbaf *cbaf = usb_get_intfdata(iface);
375
376         result = sscanf(buf, "%63s", cbaf->host_name);
377         if (result != 1)
378                 return -EINVAL;
379
380         return size;
381 }
382 static DEVICE_ATTR(wusb_host_name, 0600, cbaf_wusb_host_name_show,
383                                          cbaf_wusb_host_name_store);
384
385 static ssize_t cbaf_wusb_host_band_groups_show(struct device *dev,
386                                                struct device_attribute *attr,
387                                                char *buf)
388 {
389         struct usb_interface *iface = to_usb_interface(dev);
390         struct cbaf *cbaf = usb_get_intfdata(iface);
391
392         return scnprintf(buf, PAGE_SIZE, "0x%04x\n", cbaf->host_band_groups);
393 }
394
395 static ssize_t cbaf_wusb_host_band_groups_store(struct device *dev,
396                                                 struct device_attribute *attr,
397                                                 const char *buf, size_t size)
398 {
399         ssize_t result;
400         struct usb_interface *iface = to_usb_interface(dev);
401         struct cbaf *cbaf = usb_get_intfdata(iface);
402         u16 band_groups = 0;
403
404         result = sscanf(buf, "%04hx", &band_groups);
405         if (result != 1)
406                 return -EINVAL;
407
408         cbaf->host_band_groups = band_groups;
409
410         return size;
411 }
412
413 static DEVICE_ATTR(wusb_host_band_groups, 0600,
414                    cbaf_wusb_host_band_groups_show,
415                    cbaf_wusb_host_band_groups_store);
416
417 static const struct wusb_cbaf_device_info cbaf_device_info_defaults = {
418         .Length_hdr               = WUSB_AR_Length,
419         .CDID_hdr                 = WUSB_AR_CDID,
420         .BandGroups_hdr           = WUSB_AR_BandGroups,
421         .LangID_hdr               = WUSB_AR_LangID,
422         .DeviceFriendlyName_hdr   = WUSB_AR_DeviceFriendlyName,
423 };
424
425 static ssize_t cbaf_wusb_cdid_show(struct device *dev,
426                                    struct device_attribute *attr, char *buf)
427 {
428         struct usb_interface *iface = to_usb_interface(dev);
429         struct cbaf *cbaf = usb_get_intfdata(iface);
430         char pr_cdid[WUSB_CKHDID_STRSIZE];
431
432         ckhdid_printf(pr_cdid, sizeof(pr_cdid), &cbaf->cdid);
433         return scnprintf(buf, PAGE_SIZE, "%s\n", pr_cdid);
434 }
435
436 static ssize_t cbaf_wusb_cdid_store(struct device *dev,
437                                 struct device_attribute *attr,
438                                 const char *buf, size_t size)
439 {
440         ssize_t result;
441         struct usb_interface *iface = to_usb_interface(dev);
442         struct cbaf *cbaf = usb_get_intfdata(iface);
443         struct wusb_ckhdid cdid;
444
445         result = sscanf(buf,
446                         "%02hhx %02hhx %02hhx %02hhx "
447                         "%02hhx %02hhx %02hhx %02hhx "
448                         "%02hhx %02hhx %02hhx %02hhx "
449                         "%02hhx %02hhx %02hhx %02hhx",
450                         &cdid.data[0] , &cdid.data[1],
451                         &cdid.data[2] , &cdid.data[3],
452                         &cdid.data[4] , &cdid.data[5],
453                         &cdid.data[6] , &cdid.data[7],
454                         &cdid.data[8] , &cdid.data[9],
455                         &cdid.data[10], &cdid.data[11],
456                         &cdid.data[12], &cdid.data[13],
457                         &cdid.data[14], &cdid.data[15]);
458         if (result != 16)
459                 return -EINVAL;
460
461         cbaf->cdid = cdid;
462
463         return size;
464 }
465 static DEVICE_ATTR(wusb_cdid, 0600, cbaf_wusb_cdid_show, cbaf_wusb_cdid_store);
466
467 static ssize_t cbaf_wusb_device_band_groups_show(struct device *dev,
468                                                  struct device_attribute *attr,
469                                                  char *buf)
470 {
471         struct usb_interface *iface = to_usb_interface(dev);
472         struct cbaf *cbaf = usb_get_intfdata(iface);
473
474         return scnprintf(buf, PAGE_SIZE, "0x%04x\n", cbaf->device_band_groups);
475 }
476
477 static DEVICE_ATTR(wusb_device_band_groups, 0600,
478                    cbaf_wusb_device_band_groups_show,
479                    NULL);
480
481 static ssize_t cbaf_wusb_device_name_show(struct device *dev,
482                                         struct device_attribute *attr,
483                                         char *buf)
484 {
485         struct usb_interface *iface = to_usb_interface(dev);
486         struct cbaf *cbaf = usb_get_intfdata(iface);
487
488         return scnprintf(buf, PAGE_SIZE, "%s\n", cbaf->device_name);
489 }
490 static DEVICE_ATTR(wusb_device_name, 0600, cbaf_wusb_device_name_show, NULL);
491
492 static const struct wusb_cbaf_cc_data cbaf_cc_data_defaults = {
493         .AssociationTypeId_hdr    = WUSB_AR_AssociationTypeId,
494         .AssociationTypeId        = cpu_to_le16(AR_TYPE_WUSB),
495         .AssociationSubTypeId_hdr = WUSB_AR_AssociationSubTypeId,
496         .AssociationSubTypeId     = cpu_to_le16(AR_TYPE_WUSB_ASSOCIATE),
497         .Length_hdr               = WUSB_AR_Length,
498         .Length                   = cpu_to_le32(sizeof(struct wusb_cbaf_cc_data)),
499         .ConnectionContext_hdr    = WUSB_AR_ConnectionContext,
500         .BandGroups_hdr           = WUSB_AR_BandGroups,
501 };
502
503 static const struct wusb_cbaf_cc_data_fail cbaf_cc_data_fail_defaults = {
504         .AssociationTypeId_hdr    = WUSB_AR_AssociationTypeId,
505         .AssociationSubTypeId_hdr = WUSB_AR_AssociationSubTypeId,
506         .Length_hdr               = WUSB_AR_Length,
507         .AssociationStatus_hdr    = WUSB_AR_AssociationStatus,
508 };
509
510 /*
511  * Send a new CC to the device.
512  */
513 static int cbaf_cc_upload(struct cbaf *cbaf)
514 {
515         int result;
516         struct device *dev = &cbaf->usb_iface->dev;
517         struct wusb_cbaf_cc_data *ccd;
518         char pr_cdid[WUSB_CKHDID_STRSIZE];
519
520         ccd =  cbaf->buffer;
521         *ccd = cbaf_cc_data_defaults;
522         ccd->CHID = cbaf->chid;
523         ccd->CDID = cbaf->cdid;
524         ccd->CK = cbaf->ck;
525         ccd->BandGroups = cpu_to_le16(cbaf->host_band_groups);
526
527         dev_dbg(dev, "Trying to upload CC:\n");
528         ckhdid_printf(pr_cdid, sizeof(pr_cdid), &ccd->CHID);
529         dev_dbg(dev, "  CHID       %s\n", pr_cdid);
530         ckhdid_printf(pr_cdid, sizeof(pr_cdid), &ccd->CDID);
531         dev_dbg(dev, "  CDID       %s\n", pr_cdid);
532         dev_dbg(dev, "  Bandgroups 0x%04x\n", cbaf->host_band_groups);
533
534         result = usb_control_msg(
535                 cbaf->usb_dev, usb_sndctrlpipe(cbaf->usb_dev, 0),
536                 CBAF_REQ_SET_ASSOCIATION_RESPONSE,
537                 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
538                 0x0201, cbaf->usb_iface->cur_altsetting->desc.bInterfaceNumber,
539                 ccd, sizeof(*ccd), 1000 /* FIXME: arbitrary */);
540
541         return result;
542 }
543
544 static ssize_t cbaf_wusb_ck_store(struct device *dev,
545                                   struct device_attribute *attr,
546                                   const char *buf, size_t size)
547 {
548         ssize_t result;
549         struct usb_interface *iface = to_usb_interface(dev);
550         struct cbaf *cbaf = usb_get_intfdata(iface);
551
552         result = sscanf(buf,
553                         "%02hhx %02hhx %02hhx %02hhx "
554                         "%02hhx %02hhx %02hhx %02hhx "
555                         "%02hhx %02hhx %02hhx %02hhx "
556                         "%02hhx %02hhx %02hhx %02hhx",
557                         &cbaf->ck.data[0] , &cbaf->ck.data[1],
558                         &cbaf->ck.data[2] , &cbaf->ck.data[3],
559                         &cbaf->ck.data[4] , &cbaf->ck.data[5],
560                         &cbaf->ck.data[6] , &cbaf->ck.data[7],
561                         &cbaf->ck.data[8] , &cbaf->ck.data[9],
562                         &cbaf->ck.data[10], &cbaf->ck.data[11],
563                         &cbaf->ck.data[12], &cbaf->ck.data[13],
564                         &cbaf->ck.data[14], &cbaf->ck.data[15]);
565         if (result != 16)
566                 return -EINVAL;
567
568         result = cbaf_cc_upload(cbaf);
569         if (result < 0)
570                 return result;
571
572         return size;
573 }
574 static DEVICE_ATTR(wusb_ck, 0600, NULL, cbaf_wusb_ck_store);
575
576 static struct attribute *cbaf_dev_attrs[] = {
577         &dev_attr_wusb_host_name.attr,
578         &dev_attr_wusb_host_band_groups.attr,
579         &dev_attr_wusb_chid.attr,
580         &dev_attr_wusb_cdid.attr,
581         &dev_attr_wusb_device_name.attr,
582         &dev_attr_wusb_device_band_groups.attr,
583         &dev_attr_wusb_ck.attr,
584         NULL,
585 };
586
587 static struct attribute_group cbaf_dev_attr_group = {
588         .name = NULL,   /* we want them in the same directory */
589         .attrs = cbaf_dev_attrs,
590 };
591
592 static int cbaf_probe(struct usb_interface *iface,
593                       const struct usb_device_id *id)
594 {
595         struct cbaf *cbaf;
596         struct device *dev = &iface->dev;
597         int result = -ENOMEM;
598
599         cbaf = kzalloc(sizeof(*cbaf), GFP_KERNEL);
600         if (cbaf == NULL)
601                 goto error_kzalloc;
602         cbaf->buffer = kmalloc(512, GFP_KERNEL);
603         if (cbaf->buffer == NULL)
604                 goto error_kmalloc_buffer;
605
606         cbaf->buffer_size = 512;
607         cbaf->usb_dev = usb_get_dev(interface_to_usbdev(iface));
608         cbaf->usb_iface = usb_get_intf(iface);
609         result = cbaf_check(cbaf);
610         if (result < 0) {
611                 dev_err(dev, "This device is not WUSB-CBAF compliant"
612                         "and is not supported yet.\n");
613                 goto error_check;
614         }
615
616         result = sysfs_create_group(&dev->kobj, &cbaf_dev_attr_group);
617         if (result < 0) {
618                 dev_err(dev, "Can't register sysfs attr group: %d\n", result);
619                 goto error_create_group;
620         }
621         usb_set_intfdata(iface, cbaf);
622         return 0;
623
624 error_create_group:
625 error_check:
626         kfree(cbaf->buffer);
627 error_kmalloc_buffer:
628         kfree(cbaf);
629 error_kzalloc:
630         return result;
631 }
632
633 static void cbaf_disconnect(struct usb_interface *iface)
634 {
635         struct cbaf *cbaf = usb_get_intfdata(iface);
636         struct device *dev = &iface->dev;
637         sysfs_remove_group(&dev->kobj, &cbaf_dev_attr_group);
638         usb_set_intfdata(iface, NULL);
639         usb_put_intf(iface);
640         kfree(cbaf->buffer);
641         /* paranoia: clean up crypto keys */
642         memset(cbaf, 0, sizeof(*cbaf));
643         kfree(cbaf);
644 }
645
646 static struct usb_device_id cbaf_id_table[] = {
647         { USB_INTERFACE_INFO(0xef, 0x03, 0x01), },
648         { },
649 };
650 MODULE_DEVICE_TABLE(usb, cbaf_id_table);
651
652 static struct usb_driver cbaf_driver = {
653         .name =         "wusb-cbaf",
654         .id_table =     cbaf_id_table,
655         .probe =        cbaf_probe,
656         .disconnect =   cbaf_disconnect,
657 };
658
659 static int __init cbaf_driver_init(void)
660 {
661         return usb_register(&cbaf_driver);
662 }
663 module_init(cbaf_driver_init);
664
665 static void __exit cbaf_driver_exit(void)
666 {
667         usb_deregister(&cbaf_driver);
668 }
669 module_exit(cbaf_driver_exit);
670
671 MODULE_AUTHOR("Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>");
672 MODULE_DESCRIPTION("Wireless USB Cable Based Association");
673 MODULE_LICENSE("GPL");