1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * f_hid.c -- USB HID function driver
4 *
5 * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
6 */
7
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/hid.h>
11 #include <linux/idr.h>
12 #include <linux/cdev.h>
13 #include <linux/mutex.h>
14 #include <linux/poll.h>
15 #include <linux/uaccess.h>
16 #include <linux/wait.h>
17 #include <linux/sched.h>
18 #include <linux/usb/g_hid.h>
19
20 #include "u_f.h"
21 #include "u_hid.h"
22
23 #define HIDG_MINORS 4
24
25 static int major, minors;
26
27 static const struct class hidg_class = {
28 .name = "hidg",
29 };
30
31 static DEFINE_IDA(hidg_ida);
32 static DEFINE_MUTEX(hidg_ida_lock); /* protects access to hidg_ida */
33
34 /*-------------------------------------------------------------------------*/
35 /* HID gadget struct */
36
37 struct f_hidg_req_list {
38 struct usb_request *req;
39 unsigned int pos;
40 struct list_head list;
41 };
42
43 struct f_hidg {
44 /* configuration */
45 unsigned char bInterfaceSubClass;
46 unsigned char bInterfaceProtocol;
47 unsigned char protocol;
48 unsigned char idle;
49 unsigned short report_desc_length;
50 char *report_desc;
51 unsigned short report_length;
52 /*
53 * use_out_ep - if true, the OUT Endpoint (interrupt out method)
54 * will be used to receive reports from the host
55 * using functions with the "intout" suffix.
56 * Otherwise, the OUT Endpoint will not be configured
57 * and the SETUP/SET_REPORT method ("ssreport" suffix)
58 * will be used to receive reports.
59 */
60 bool use_out_ep;
61
62 /* recv report */
63 spinlock_t read_spinlock;
64 wait_queue_head_t read_queue;
65 /* recv report - interrupt out only (use_out_ep == 1) */
66 struct list_head completed_out_req;
67 unsigned int qlen;
68 /* recv report - setup set_report only (use_out_ep == 0) */
69 char *set_report_buf;
70 unsigned int set_report_length;
71
72 /* send report */
73 spinlock_t write_spinlock;
74 bool write_pending;
75 wait_queue_head_t write_queue;
76 struct usb_request *req;
77
78 struct device dev;
79 struct cdev cdev;
80 struct usb_function func;
81
82 struct usb_ep *in_ep;
83 struct usb_ep *out_ep;
84 };
85
func_to_hidg(struct usb_function * f)86 static inline struct f_hidg *func_to_hidg(struct usb_function *f)
87 {
88 return container_of(f, struct f_hidg, func);
89 }
90
hidg_release(struct device * dev)91 static void hidg_release(struct device *dev)
92 {
93 struct f_hidg *hidg = container_of(dev, struct f_hidg, dev);
94
95 kfree(hidg->set_report_buf);
96 kfree(hidg);
97 }
98
99 /*-------------------------------------------------------------------------*/
100 /* Static descriptors */
101
102 static struct usb_interface_descriptor hidg_interface_desc = {
103 .bLength = sizeof hidg_interface_desc,
104 .bDescriptorType = USB_DT_INTERFACE,
105 /* .bInterfaceNumber = DYNAMIC */
106 .bAlternateSetting = 0,
107 /* .bNumEndpoints = DYNAMIC (depends on use_out_ep) */
108 .bInterfaceClass = USB_CLASS_HID,
109 /* .bInterfaceSubClass = DYNAMIC */
110 /* .bInterfaceProtocol = DYNAMIC */
111 /* .iInterface = DYNAMIC */
112 };
113
114 static struct hid_descriptor hidg_desc = {
115 .bLength = sizeof hidg_desc,
116 .bDescriptorType = HID_DT_HID,
117 .bcdHID = cpu_to_le16(0x0101),
118 .bCountryCode = 0x00,
119 .bNumDescriptors = 0x1,
120 /*.desc[0].bDescriptorType = DYNAMIC */
121 /*.desc[0].wDescriptorLenght = DYNAMIC */
122 };
123
124 /* Super-Speed Support */
125
126 static struct usb_endpoint_descriptor hidg_ss_in_ep_desc = {
127 .bLength = USB_DT_ENDPOINT_SIZE,
128 .bDescriptorType = USB_DT_ENDPOINT,
129 .bEndpointAddress = USB_DIR_IN,
130 .bmAttributes = USB_ENDPOINT_XFER_INT,
131 /*.wMaxPacketSize = DYNAMIC */
132 .bInterval = 4, /* FIXME: Add this field in the
133 * HID gadget configuration?
134 * (struct hidg_func_descriptor)
135 */
136 };
137
138 static struct usb_ss_ep_comp_descriptor hidg_ss_in_comp_desc = {
139 .bLength = sizeof(hidg_ss_in_comp_desc),
140 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
141
142 /* .bMaxBurst = 0, */
143 /* .bmAttributes = 0, */
144 /* .wBytesPerInterval = DYNAMIC */
145 };
146
147 static struct usb_endpoint_descriptor hidg_ss_out_ep_desc = {
148 .bLength = USB_DT_ENDPOINT_SIZE,
149 .bDescriptorType = USB_DT_ENDPOINT,
150 .bEndpointAddress = USB_DIR_OUT,
151 .bmAttributes = USB_ENDPOINT_XFER_INT,
152 /*.wMaxPacketSize = DYNAMIC */
153 .bInterval = 4, /* FIXME: Add this field in the
154 * HID gadget configuration?
155 * (struct hidg_func_descriptor)
156 */
157 };
158
159 static struct usb_ss_ep_comp_descriptor hidg_ss_out_comp_desc = {
160 .bLength = sizeof(hidg_ss_out_comp_desc),
161 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
162
163 /* .bMaxBurst = 0, */
164 /* .bmAttributes = 0, */
165 /* .wBytesPerInterval = DYNAMIC */
166 };
167
168 static struct usb_descriptor_header *hidg_ss_descriptors_intout[] = {
169 (struct usb_descriptor_header *)&hidg_interface_desc,
170 (struct usb_descriptor_header *)&hidg_desc,
171 (struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
172 (struct usb_descriptor_header *)&hidg_ss_in_comp_desc,
173 (struct usb_descriptor_header *)&hidg_ss_out_ep_desc,
174 (struct usb_descriptor_header *)&hidg_ss_out_comp_desc,
175 NULL,
176 };
177
178 static struct usb_descriptor_header *hidg_ss_descriptors_ssreport[] = {
179 (struct usb_descriptor_header *)&hidg_interface_desc,
180 (struct usb_descriptor_header *)&hidg_desc,
181 (struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
182 (struct usb_descriptor_header *)&hidg_ss_in_comp_desc,
183 NULL,
184 };
185
186 /* High-Speed Support */
187
188 static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
189 .bLength = USB_DT_ENDPOINT_SIZE,
190 .bDescriptorType = USB_DT_ENDPOINT,
191 .bEndpointAddress = USB_DIR_IN,
192 .bmAttributes = USB_ENDPOINT_XFER_INT,
193 /*.wMaxPacketSize = DYNAMIC */
194 .bInterval = 4, /* FIXME: Add this field in the
195 * HID gadget configuration?
196 * (struct hidg_func_descriptor)
197 */
198 };
199
200 static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = {
201 .bLength = USB_DT_ENDPOINT_SIZE,
202 .bDescriptorType = USB_DT_ENDPOINT,
203 .bEndpointAddress = USB_DIR_OUT,
204 .bmAttributes = USB_ENDPOINT_XFER_INT,
205 /*.wMaxPacketSize = DYNAMIC */
206 .bInterval = 4, /* FIXME: Add this field in the
207 * HID gadget configuration?
208 * (struct hidg_func_descriptor)
209 */
210 };
211
212 static struct usb_descriptor_header *hidg_hs_descriptors_intout[] = {
213 (struct usb_descriptor_header *)&hidg_interface_desc,
214 (struct usb_descriptor_header *)&hidg_desc,
215 (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
216 (struct usb_descriptor_header *)&hidg_hs_out_ep_desc,
217 NULL,
218 };
219
220 static struct usb_descriptor_header *hidg_hs_descriptors_ssreport[] = {
221 (struct usb_descriptor_header *)&hidg_interface_desc,
222 (struct usb_descriptor_header *)&hidg_desc,
223 (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
224 NULL,
225 };
226
227 /* Full-Speed Support */
228
229 static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
230 .bLength = USB_DT_ENDPOINT_SIZE,
231 .bDescriptorType = USB_DT_ENDPOINT,
232 .bEndpointAddress = USB_DIR_IN,
233 .bmAttributes = USB_ENDPOINT_XFER_INT,
234 /*.wMaxPacketSize = DYNAMIC */
235 .bInterval = 10, /* FIXME: Add this field in the
236 * HID gadget configuration?
237 * (struct hidg_func_descriptor)
238 */
239 };
240
241 static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = {
242 .bLength = USB_DT_ENDPOINT_SIZE,
243 .bDescriptorType = USB_DT_ENDPOINT,
244 .bEndpointAddress = USB_DIR_OUT,
245 .bmAttributes = USB_ENDPOINT_XFER_INT,
246 /*.wMaxPacketSize = DYNAMIC */
247 .bInterval = 10, /* FIXME: Add this field in the
248 * HID gadget configuration?
249 * (struct hidg_func_descriptor)
250 */
251 };
252
253 static struct usb_descriptor_header *hidg_fs_descriptors_intout[] = {
254 (struct usb_descriptor_header *)&hidg_interface_desc,
255 (struct usb_descriptor_header *)&hidg_desc,
256 (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
257 (struct usb_descriptor_header *)&hidg_fs_out_ep_desc,
258 NULL,
259 };
260
261 static struct usb_descriptor_header *hidg_fs_descriptors_ssreport[] = {
262 (struct usb_descriptor_header *)&hidg_interface_desc,
263 (struct usb_descriptor_header *)&hidg_desc,
264 (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
265 NULL,
266 };
267
268 /*-------------------------------------------------------------------------*/
269 /* Strings */
270
271 #define CT_FUNC_HID_IDX 0
272
273 static struct usb_string ct_func_string_defs[] = {
274 [CT_FUNC_HID_IDX].s = "HID Interface",
275 {}, /* end of list */
276 };
277
278 static struct usb_gadget_strings ct_func_string_table = {
279 .language = 0x0409, /* en-US */
280 .strings = ct_func_string_defs,
281 };
282
283 static struct usb_gadget_strings *ct_func_strings[] = {
284 &ct_func_string_table,
285 NULL,
286 };
287
288 /*-------------------------------------------------------------------------*/
289 /* Char Device */
290
f_hidg_intout_read(struct file * file,char __user * buffer,size_t count,loff_t * ptr)291 static ssize_t f_hidg_intout_read(struct file *file, char __user *buffer,
292 size_t count, loff_t *ptr)
293 {
294 struct f_hidg *hidg = file->private_data;
295 struct f_hidg_req_list *list;
296 struct usb_request *req;
297 unsigned long flags;
298 int ret;
299
300 if (!count)
301 return 0;
302
303 spin_lock_irqsave(&hidg->read_spinlock, flags);
304
305 #define READ_COND_INTOUT (!list_empty(&hidg->completed_out_req))
306
307 /* wait for at least one buffer to complete */
308 while (!READ_COND_INTOUT) {
309 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
310 if (file->f_flags & O_NONBLOCK)
311 return -EAGAIN;
312
313 if (wait_event_interruptible(hidg->read_queue, READ_COND_INTOUT))
314 return -ERESTARTSYS;
315
316 spin_lock_irqsave(&hidg->read_spinlock, flags);
317 }
318
319 /* pick the first one */
320 list = list_first_entry(&hidg->completed_out_req,
321 struct f_hidg_req_list, list);
322
323 /*
324 * Remove this from list to protect it from beign free()
325 * while host disables our function
326 */
327 list_del(&list->list);
328
329 req = list->req;
330 count = min_t(unsigned int, count, req->actual - list->pos);
331 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
332
333 /* copy to user outside spinlock */
334 count -= copy_to_user(buffer, req->buf + list->pos, count);
335 list->pos += count;
336
337 /*
338 * if this request is completely handled and transfered to
339 * userspace, remove its entry from the list and requeue it
340 * again. Otherwise, we will revisit it again upon the next
341 * call, taking into account its current read position.
342 */
343 if (list->pos == req->actual) {
344 kfree(list);
345
346 req->length = hidg->report_length;
347 ret = usb_ep_queue(hidg->out_ep, req, GFP_KERNEL);
348 if (ret < 0) {
349 free_ep_req(hidg->out_ep, req);
350 return ret;
351 }
352 } else {
353 spin_lock_irqsave(&hidg->read_spinlock, flags);
354 list_add(&list->list, &hidg->completed_out_req);
355 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
356
357 wake_up(&hidg->read_queue);
358 }
359
360 return count;
361 }
362
363 #define READ_COND_SSREPORT (hidg->set_report_buf != NULL)
364
f_hidg_ssreport_read(struct file * file,char __user * buffer,size_t count,loff_t * ptr)365 static ssize_t f_hidg_ssreport_read(struct file *file, char __user *buffer,
366 size_t count, loff_t *ptr)
367 {
368 struct f_hidg *hidg = file->private_data;
369 char *tmp_buf = NULL;
370 unsigned long flags;
371
372 if (!count)
373 return 0;
374
375 spin_lock_irqsave(&hidg->read_spinlock, flags);
376
377 while (!READ_COND_SSREPORT) {
378 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
379 if (file->f_flags & O_NONBLOCK)
380 return -EAGAIN;
381
382 if (wait_event_interruptible(hidg->read_queue, READ_COND_SSREPORT))
383 return -ERESTARTSYS;
384
385 spin_lock_irqsave(&hidg->read_spinlock, flags);
386 }
387
388 count = min_t(unsigned int, count, hidg->set_report_length);
389 tmp_buf = hidg->set_report_buf;
390 hidg->set_report_buf = NULL;
391
392 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
393
394 if (tmp_buf != NULL) {
395 count -= copy_to_user(buffer, tmp_buf, count);
396 kfree(tmp_buf);
397 } else {
398 count = -ENOMEM;
399 }
400
401 wake_up(&hidg->read_queue);
402
403 return count;
404 }
405
f_hidg_read(struct file * file,char __user * buffer,size_t count,loff_t * ptr)406 static ssize_t f_hidg_read(struct file *file, char __user *buffer,
407 size_t count, loff_t *ptr)
408 {
409 struct f_hidg *hidg = file->private_data;
410
411 if (hidg->use_out_ep)
412 return f_hidg_intout_read(file, buffer, count, ptr);
413 else
414 return f_hidg_ssreport_read(file, buffer, count, ptr);
415 }
416
f_hidg_req_complete(struct usb_ep * ep,struct usb_request * req)417 static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
418 {
419 struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
420 unsigned long flags;
421
422 if (req->status != 0) {
423 ERROR(hidg->func.config->cdev,
424 "End Point Request ERROR: %d\n", req->status);
425 }
426
427 spin_lock_irqsave(&hidg->write_spinlock, flags);
428 hidg->write_pending = 0;
429 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
430 wake_up(&hidg->write_queue);
431 }
432
f_hidg_write(struct file * file,const char __user * buffer,size_t count,loff_t * offp)433 static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
434 size_t count, loff_t *offp)
435 {
436 struct f_hidg *hidg = file->private_data;
437 struct usb_request *req;
438 unsigned long flags;
439 ssize_t status = -ENOMEM;
440
441 spin_lock_irqsave(&hidg->write_spinlock, flags);
442
443 if (!hidg->req) {
444 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
445 return -ESHUTDOWN;
446 }
447
448 #define WRITE_COND (!hidg->write_pending)
449 try_again:
450 /* write queue */
451 while (!WRITE_COND) {
452 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
453 if (file->f_flags & O_NONBLOCK)
454 return -EAGAIN;
455
456 if (wait_event_interruptible_exclusive(
457 hidg->write_queue, WRITE_COND))
458 return -ERESTARTSYS;
459
460 spin_lock_irqsave(&hidg->write_spinlock, flags);
461 }
462
463 hidg->write_pending = 1;
464 req = hidg->req;
465 count = min_t(unsigned, count, hidg->report_length);
466
467 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
468
469 if (!req) {
470 ERROR(hidg->func.config->cdev, "hidg->req is NULL\n");
471 status = -ESHUTDOWN;
472 goto release_write_pending;
473 }
474
475 status = copy_from_user(req->buf, buffer, count);
476 if (status != 0) {
477 ERROR(hidg->func.config->cdev,
478 "copy_from_user error\n");
479 status = -EINVAL;
480 goto release_write_pending;
481 }
482
483 spin_lock_irqsave(&hidg->write_spinlock, flags);
484
485 /* when our function has been disabled by host */
486 if (!hidg->req) {
487 free_ep_req(hidg->in_ep, req);
488 /*
489 * TODO
490 * Should we fail with error here?
491 */
492 goto try_again;
493 }
494
495 req->status = 0;
496 req->zero = 0;
497 req->length = count;
498 req->complete = f_hidg_req_complete;
499 req->context = hidg;
500
501 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
502
503 if (!hidg->in_ep->enabled) {
504 ERROR(hidg->func.config->cdev, "in_ep is disabled\n");
505 status = -ESHUTDOWN;
506 goto release_write_pending;
507 }
508
509 status = usb_ep_queue(hidg->in_ep, req, GFP_ATOMIC);
510 if (status < 0)
511 goto release_write_pending;
512 else
513 status = count;
514
515 return status;
516 release_write_pending:
517 spin_lock_irqsave(&hidg->write_spinlock, flags);
518 hidg->write_pending = 0;
519 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
520
521 wake_up(&hidg->write_queue);
522
523 return status;
524 }
525
f_hidg_poll(struct file * file,poll_table * wait)526 static __poll_t f_hidg_poll(struct file *file, poll_table *wait)
527 {
528 struct f_hidg *hidg = file->private_data;
529 __poll_t ret = 0;
530
531 poll_wait(file, &hidg->read_queue, wait);
532 poll_wait(file, &hidg->write_queue, wait);
533
534 if (WRITE_COND)
535 ret |= EPOLLOUT | EPOLLWRNORM;
536
537 if (hidg->use_out_ep) {
538 if (READ_COND_INTOUT)
539 ret |= EPOLLIN | EPOLLRDNORM;
540 } else {
541 if (READ_COND_SSREPORT)
542 ret |= EPOLLIN | EPOLLRDNORM;
543 }
544
545 return ret;
546 }
547
548 #undef WRITE_COND
549 #undef READ_COND_SSREPORT
550 #undef READ_COND_INTOUT
551
f_hidg_release(struct inode * inode,struct file * fd)552 static int f_hidg_release(struct inode *inode, struct file *fd)
553 {
554 fd->private_data = NULL;
555 return 0;
556 }
557
f_hidg_open(struct inode * inode,struct file * fd)558 static int f_hidg_open(struct inode *inode, struct file *fd)
559 {
560 struct f_hidg *hidg =
561 container_of(inode->i_cdev, struct f_hidg, cdev);
562
563 fd->private_data = hidg;
564
565 return 0;
566 }
567
568 /*-------------------------------------------------------------------------*/
569 /* usb_function */
570
hidg_alloc_ep_req(struct usb_ep * ep,unsigned length)571 static inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep,
572 unsigned length)
573 {
574 return alloc_ep_req(ep, length);
575 }
576
hidg_intout_complete(struct usb_ep * ep,struct usb_request * req)577 static void hidg_intout_complete(struct usb_ep *ep, struct usb_request *req)
578 {
579 struct f_hidg *hidg = (struct f_hidg *) req->context;
580 struct usb_composite_dev *cdev = hidg->func.config->cdev;
581 struct f_hidg_req_list *req_list;
582 unsigned long flags;
583
584 switch (req->status) {
585 case 0:
586 req_list = kzalloc(sizeof(*req_list), GFP_ATOMIC);
587 if (!req_list) {
588 ERROR(cdev, "Unable to allocate mem for req_list\n");
589 goto free_req;
590 }
591
592 req_list->req = req;
593
594 spin_lock_irqsave(&hidg->read_spinlock, flags);
595 list_add_tail(&req_list->list, &hidg->completed_out_req);
596 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
597
598 wake_up(&hidg->read_queue);
599 break;
600 default:
601 ERROR(cdev, "Set report failed %d\n", req->status);
602 fallthrough;
603 case -ECONNABORTED: /* hardware forced ep reset */
604 case -ECONNRESET: /* request dequeued */
605 case -ESHUTDOWN: /* disconnect from host */
606 free_req:
607 free_ep_req(ep, req);
608 return;
609 }
610 }
611
hidg_ssreport_complete(struct usb_ep * ep,struct usb_request * req)612 static void hidg_ssreport_complete(struct usb_ep *ep, struct usb_request *req)
613 {
614 struct f_hidg *hidg = (struct f_hidg *)req->context;
615 struct usb_composite_dev *cdev = hidg->func.config->cdev;
616 char *new_buf = NULL;
617 unsigned long flags;
618
619 if (req->status != 0 || req->buf == NULL || req->actual == 0) {
620 ERROR(cdev,
621 "%s FAILED: status=%d, buf=%p, actual=%d\n",
622 __func__, req->status, req->buf, req->actual);
623 return;
624 }
625
626 spin_lock_irqsave(&hidg->read_spinlock, flags);
627
628 new_buf = krealloc(hidg->set_report_buf, req->actual, GFP_ATOMIC);
629 if (new_buf == NULL) {
630 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
631 return;
632 }
633 hidg->set_report_buf = new_buf;
634
635 hidg->set_report_length = req->actual;
636 memcpy(hidg->set_report_buf, req->buf, req->actual);
637
638 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
639
640 wake_up(&hidg->read_queue);
641 }
642
hidg_setup(struct usb_function * f,const struct usb_ctrlrequest * ctrl)643 static int hidg_setup(struct usb_function *f,
644 const struct usb_ctrlrequest *ctrl)
645 {
646 struct f_hidg *hidg = func_to_hidg(f);
647 struct usb_composite_dev *cdev = f->config->cdev;
648 struct usb_request *req = cdev->req;
649 int status = 0;
650 __u16 value, length;
651
652 value = __le16_to_cpu(ctrl->wValue);
653 length = __le16_to_cpu(ctrl->wLength);
654
655 VDBG(cdev,
656 "%s crtl_request : bRequestType:0x%x bRequest:0x%x Value:0x%x\n",
657 __func__, ctrl->bRequestType, ctrl->bRequest, value);
658
659 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
660 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
661 | HID_REQ_GET_REPORT):
662 VDBG(cdev, "get_report\n");
663
664 /* send an empty report */
665 length = min_t(unsigned, length, hidg->report_length);
666 memset(req->buf, 0x0, length);
667
668 goto respond;
669 break;
670
671 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
672 | HID_REQ_GET_PROTOCOL):
673 VDBG(cdev, "get_protocol\n");
674 length = min_t(unsigned int, length, 1);
675 ((u8 *) req->buf)[0] = hidg->protocol;
676 goto respond;
677 break;
678
679 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
680 | HID_REQ_GET_IDLE):
681 VDBG(cdev, "get_idle\n");
682 length = min_t(unsigned int, length, 1);
683 ((u8 *) req->buf)[0] = hidg->idle;
684 goto respond;
685 break;
686
687 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
688 | HID_REQ_SET_REPORT):
689 VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength);
690 if (hidg->use_out_ep)
691 goto stall;
692 req->complete = hidg_ssreport_complete;
693 req->context = hidg;
694 goto respond;
695 break;
696
697 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
698 | HID_REQ_SET_PROTOCOL):
699 VDBG(cdev, "set_protocol\n");
700 if (value > HID_REPORT_PROTOCOL)
701 goto stall;
702 length = 0;
703 /*
704 * We assume that programs implementing the Boot protocol
705 * are also compatible with the Report Protocol
706 */
707 if (hidg->bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {
708 hidg->protocol = value;
709 goto respond;
710 }
711 goto stall;
712 break;
713
714 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
715 | HID_REQ_SET_IDLE):
716 VDBG(cdev, "set_idle\n");
717 length = 0;
718 hidg->idle = value >> 8;
719 goto respond;
720 break;
721
722 case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
723 | USB_REQ_GET_DESCRIPTOR):
724 switch (value >> 8) {
725 case HID_DT_HID:
726 {
727 struct hid_descriptor hidg_desc_copy = hidg_desc;
728
729 VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n");
730 hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT;
731 hidg_desc_copy.desc[0].wDescriptorLength =
732 cpu_to_le16(hidg->report_desc_length);
733
734 length = min_t(unsigned short, length,
735 hidg_desc_copy.bLength);
736 memcpy(req->buf, &hidg_desc_copy, length);
737 goto respond;
738 break;
739 }
740 case HID_DT_REPORT:
741 VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
742 length = min_t(unsigned short, length,
743 hidg->report_desc_length);
744 memcpy(req->buf, hidg->report_desc, length);
745 goto respond;
746 break;
747
748 default:
749 VDBG(cdev, "Unknown descriptor request 0x%x\n",
750 value >> 8);
751 goto stall;
752 break;
753 }
754 break;
755
756 default:
757 VDBG(cdev, "Unknown request 0x%x\n",
758 ctrl->bRequest);
759 goto stall;
760 break;
761 }
762
763 stall:
764 return -EOPNOTSUPP;
765
766 respond:
767 req->zero = 0;
768 req->length = length;
769 status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
770 if (status < 0)
771 ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
772 return status;
773 }
774
hidg_disable(struct usb_function * f)775 static void hidg_disable(struct usb_function *f)
776 {
777 struct f_hidg *hidg = func_to_hidg(f);
778 struct f_hidg_req_list *list, *next;
779 unsigned long flags;
780
781 usb_ep_disable(hidg->in_ep);
782
783 if (hidg->out_ep) {
784 usb_ep_disable(hidg->out_ep);
785
786 spin_lock_irqsave(&hidg->read_spinlock, flags);
787 list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
788 free_ep_req(hidg->out_ep, list->req);
789 list_del(&list->list);
790 kfree(list);
791 }
792 spin_unlock_irqrestore(&hidg->read_spinlock, flags);
793 }
794
795 spin_lock_irqsave(&hidg->write_spinlock, flags);
796 if (!hidg->write_pending) {
797 free_ep_req(hidg->in_ep, hidg->req);
798 hidg->write_pending = 1;
799 }
800
801 hidg->req = NULL;
802 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
803 }
804
hidg_set_alt(struct usb_function * f,unsigned intf,unsigned alt)805 static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
806 {
807 struct usb_composite_dev *cdev = f->config->cdev;
808 struct f_hidg *hidg = func_to_hidg(f);
809 struct usb_request *req_in = NULL;
810 unsigned long flags;
811 int i, status = 0;
812
813 VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);
814
815 if (hidg->in_ep != NULL) {
816 /* restart endpoint */
817 usb_ep_disable(hidg->in_ep);
818
819 status = config_ep_by_speed(f->config->cdev->gadget, f,
820 hidg->in_ep);
821 if (status) {
822 ERROR(cdev, "config_ep_by_speed FAILED!\n");
823 goto fail;
824 }
825 status = usb_ep_enable(hidg->in_ep);
826 if (status < 0) {
827 ERROR(cdev, "Enable IN endpoint FAILED!\n");
828 goto fail;
829 }
830 hidg->in_ep->driver_data = hidg;
831
832 req_in = hidg_alloc_ep_req(hidg->in_ep, hidg->report_length);
833 if (!req_in) {
834 status = -ENOMEM;
835 goto disable_ep_in;
836 }
837 }
838
839 if (hidg->use_out_ep && hidg->out_ep != NULL) {
840 /* restart endpoint */
841 usb_ep_disable(hidg->out_ep);
842
843 status = config_ep_by_speed(f->config->cdev->gadget, f,
844 hidg->out_ep);
845 if (status) {
846 ERROR(cdev, "config_ep_by_speed FAILED!\n");
847 goto free_req_in;
848 }
849 status = usb_ep_enable(hidg->out_ep);
850 if (status < 0) {
851 ERROR(cdev, "Enable OUT endpoint FAILED!\n");
852 goto free_req_in;
853 }
854 hidg->out_ep->driver_data = hidg;
855
856 /*
857 * allocate a bunch of read buffers and queue them all at once.
858 */
859 for (i = 0; i < hidg->qlen && status == 0; i++) {
860 struct usb_request *req =
861 hidg_alloc_ep_req(hidg->out_ep,
862 hidg->report_length);
863 if (req) {
864 req->complete = hidg_intout_complete;
865 req->context = hidg;
866 status = usb_ep_queue(hidg->out_ep, req,
867 GFP_ATOMIC);
868 if (status) {
869 ERROR(cdev, "%s queue req --> %d\n",
870 hidg->out_ep->name, status);
871 free_ep_req(hidg->out_ep, req);
872 }
873 } else {
874 status = -ENOMEM;
875 goto disable_out_ep;
876 }
877 }
878 }
879
880 if (hidg->in_ep != NULL) {
881 spin_lock_irqsave(&hidg->write_spinlock, flags);
882 hidg->req = req_in;
883 hidg->write_pending = 0;
884 spin_unlock_irqrestore(&hidg->write_spinlock, flags);
885
886 wake_up(&hidg->write_queue);
887 }
888 return 0;
889 disable_out_ep:
890 if (hidg->out_ep)
891 usb_ep_disable(hidg->out_ep);
892 free_req_in:
893 if (req_in)
894 free_ep_req(hidg->in_ep, req_in);
895
896 disable_ep_in:
897 if (hidg->in_ep)
898 usb_ep_disable(hidg->in_ep);
899
900 fail:
901 return status;
902 }
903
904 static const struct file_operations f_hidg_fops = {
905 .owner = THIS_MODULE,
906 .open = f_hidg_open,
907 .release = f_hidg_release,
908 .write = f_hidg_write,
909 .read = f_hidg_read,
910 .poll = f_hidg_poll,
911 .llseek = noop_llseek,
912 };
913
hidg_bind(struct usb_configuration * c,struct usb_function * f)914 static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
915 {
916 struct usb_ep *ep;
917 struct f_hidg *hidg = func_to_hidg(f);
918 struct usb_string *us;
919 int status;
920
921 /* maybe allocate device-global string IDs, and patch descriptors */
922 us = usb_gstrings_attach(c->cdev, ct_func_strings,
923 ARRAY_SIZE(ct_func_string_defs));
924 if (IS_ERR(us))
925 return PTR_ERR(us);
926 hidg_interface_desc.iInterface = us[CT_FUNC_HID_IDX].id;
927
928 /* allocate instance-specific interface IDs, and patch descriptors */
929 status = usb_interface_id(c, f);
930 if (status < 0)
931 goto fail;
932 hidg_interface_desc.bInterfaceNumber = status;
933
934 /* allocate instance-specific endpoints */
935 status = -ENODEV;
936 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
937 if (!ep)
938 goto fail;
939 hidg->in_ep = ep;
940
941 hidg->out_ep = NULL;
942 if (hidg->use_out_ep) {
943 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
944 if (!ep)
945 goto fail;
946 hidg->out_ep = ep;
947 }
948
949 /* used only if use_out_ep == 1 */
950 hidg->set_report_buf = NULL;
951
952 /* set descriptor dynamic values */
953 hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
954 hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
955 hidg_interface_desc.bNumEndpoints = hidg->use_out_ep ? 2 : 1;
956 hidg->protocol = HID_REPORT_PROTOCOL;
957 hidg->idle = 1;
958 hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
959 hidg_ss_in_comp_desc.wBytesPerInterval =
960 cpu_to_le16(hidg->report_length);
961 hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
962 hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
963 hidg_ss_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
964 hidg_ss_out_comp_desc.wBytesPerInterval =
965 cpu_to_le16(hidg->report_length);
966 hidg_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
967 hidg_fs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
968 /*
969 * We can use hidg_desc struct here but we should not relay
970 * that its content won't change after returning from this function.
971 */
972 hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
973 hidg_desc.desc[0].wDescriptorLength =
974 cpu_to_le16(hidg->report_desc_length);
975
976 hidg_hs_in_ep_desc.bEndpointAddress =
977 hidg_fs_in_ep_desc.bEndpointAddress;
978 hidg_hs_out_ep_desc.bEndpointAddress =
979 hidg_fs_out_ep_desc.bEndpointAddress;
980
981 hidg_ss_in_ep_desc.bEndpointAddress =
982 hidg_fs_in_ep_desc.bEndpointAddress;
983 hidg_ss_out_ep_desc.bEndpointAddress =
984 hidg_fs_out_ep_desc.bEndpointAddress;
985
986 if (hidg->use_out_ep)
987 status = usb_assign_descriptors(f,
988 hidg_fs_descriptors_intout,
989 hidg_hs_descriptors_intout,
990 hidg_ss_descriptors_intout,
991 hidg_ss_descriptors_intout);
992 else
993 status = usb_assign_descriptors(f,
994 hidg_fs_descriptors_ssreport,
995 hidg_hs_descriptors_ssreport,
996 hidg_ss_descriptors_ssreport,
997 hidg_ss_descriptors_ssreport);
998
999 if (status)
1000 goto fail;
1001
1002 spin_lock_init(&hidg->write_spinlock);
1003 hidg->write_pending = 1;
1004 hidg->req = NULL;
1005 spin_lock_init(&hidg->read_spinlock);
1006 init_waitqueue_head(&hidg->write_queue);
1007 init_waitqueue_head(&hidg->read_queue);
1008 INIT_LIST_HEAD(&hidg->completed_out_req);
1009
1010 /* create char device */
1011 cdev_init(&hidg->cdev, &f_hidg_fops);
1012 status = cdev_device_add(&hidg->cdev, &hidg->dev);
1013 if (status)
1014 goto fail_free_descs;
1015
1016 return 0;
1017 fail_free_descs:
1018 usb_free_all_descriptors(f);
1019 fail:
1020 ERROR(f->config->cdev, "hidg_bind FAILED\n");
1021 if (hidg->req != NULL)
1022 free_ep_req(hidg->in_ep, hidg->req);
1023
1024 return status;
1025 }
1026
hidg_get_minor(void)1027 static inline int hidg_get_minor(void)
1028 {
1029 int ret;
1030
1031 ret = ida_simple_get(&hidg_ida, 0, 0, GFP_KERNEL);
1032 if (ret >= HIDG_MINORS) {
1033 ida_simple_remove(&hidg_ida, ret);
1034 ret = -ENODEV;
1035 }
1036
1037 return ret;
1038 }
1039
to_f_hid_opts(struct config_item * item)1040 static inline struct f_hid_opts *to_f_hid_opts(struct config_item *item)
1041 {
1042 return container_of(to_config_group(item), struct f_hid_opts,
1043 func_inst.group);
1044 }
1045
hid_attr_release(struct config_item * item)1046 static void hid_attr_release(struct config_item *item)
1047 {
1048 struct f_hid_opts *opts = to_f_hid_opts(item);
1049
1050 usb_put_function_instance(&opts->func_inst);
1051 }
1052
1053 static struct configfs_item_operations hidg_item_ops = {
1054 .release = hid_attr_release,
1055 };
1056
1057 #define F_HID_OPT(name, prec, limit) \
1058 static ssize_t f_hid_opts_##name##_show(struct config_item *item, char *page)\
1059 { \
1060 struct f_hid_opts *opts = to_f_hid_opts(item); \
1061 int result; \
1062 \
1063 mutex_lock(&opts->lock); \
1064 result = sprintf(page, "%d\n", opts->name); \
1065 mutex_unlock(&opts->lock); \
1066 \
1067 return result; \
1068 } \
1069 \
1070 static ssize_t f_hid_opts_##name##_store(struct config_item *item, \
1071 const char *page, size_t len) \
1072 { \
1073 struct f_hid_opts *opts = to_f_hid_opts(item); \
1074 int ret; \
1075 u##prec num; \
1076 \
1077 mutex_lock(&opts->lock); \
1078 if (opts->refcnt) { \
1079 ret = -EBUSY; \
1080 goto end; \
1081 } \
1082 \
1083 ret = kstrtou##prec(page, 0, &num); \
1084 if (ret) \
1085 goto end; \
1086 \
1087 if (num > limit) { \
1088 ret = -EINVAL; \
1089 goto end; \
1090 } \
1091 opts->name = num; \
1092 ret = len; \
1093 \
1094 end: \
1095 mutex_unlock(&opts->lock); \
1096 return ret; \
1097 } \
1098 \
1099 CONFIGFS_ATTR(f_hid_opts_, name)
1100
1101 F_HID_OPT(subclass, 8, 255);
1102 F_HID_OPT(protocol, 8, 255);
1103 F_HID_OPT(no_out_endpoint, 8, 1);
1104 F_HID_OPT(report_length, 16, 65535);
1105
f_hid_opts_report_desc_show(struct config_item * item,char * page)1106 static ssize_t f_hid_opts_report_desc_show(struct config_item *item, char *page)
1107 {
1108 struct f_hid_opts *opts = to_f_hid_opts(item);
1109 int result;
1110
1111 mutex_lock(&opts->lock);
1112 result = opts->report_desc_length;
1113 memcpy(page, opts->report_desc, opts->report_desc_length);
1114 mutex_unlock(&opts->lock);
1115
1116 return result;
1117 }
1118
f_hid_opts_report_desc_store(struct config_item * item,const char * page,size_t len)1119 static ssize_t f_hid_opts_report_desc_store(struct config_item *item,
1120 const char *page, size_t len)
1121 {
1122 struct f_hid_opts *opts = to_f_hid_opts(item);
1123 int ret = -EBUSY;
1124 char *d;
1125
1126 mutex_lock(&opts->lock);
1127
1128 if (opts->refcnt)
1129 goto end;
1130 if (len > PAGE_SIZE) {
1131 ret = -ENOSPC;
1132 goto end;
1133 }
1134 d = kmemdup(page, len, GFP_KERNEL);
1135 if (!d) {
1136 ret = -ENOMEM;
1137 goto end;
1138 }
1139 kfree(opts->report_desc);
1140 opts->report_desc = d;
1141 opts->report_desc_length = len;
1142 opts->report_desc_alloc = true;
1143 ret = len;
1144 end:
1145 mutex_unlock(&opts->lock);
1146 return ret;
1147 }
1148
1149 CONFIGFS_ATTR(f_hid_opts_, report_desc);
1150
f_hid_opts_dev_show(struct config_item * item,char * page)1151 static ssize_t f_hid_opts_dev_show(struct config_item *item, char *page)
1152 {
1153 struct f_hid_opts *opts = to_f_hid_opts(item);
1154
1155 return sprintf(page, "%d:%d\n", major, opts->minor);
1156 }
1157
1158 CONFIGFS_ATTR_RO(f_hid_opts_, dev);
1159
1160 static struct configfs_attribute *hid_attrs[] = {
1161 &f_hid_opts_attr_subclass,
1162 &f_hid_opts_attr_protocol,
1163 &f_hid_opts_attr_no_out_endpoint,
1164 &f_hid_opts_attr_report_length,
1165 &f_hid_opts_attr_report_desc,
1166 &f_hid_opts_attr_dev,
1167 NULL,
1168 };
1169
1170 static const struct config_item_type hid_func_type = {
1171 .ct_item_ops = &hidg_item_ops,
1172 .ct_attrs = hid_attrs,
1173 .ct_owner = THIS_MODULE,
1174 };
1175
hidg_put_minor(int minor)1176 static inline void hidg_put_minor(int minor)
1177 {
1178 ida_simple_remove(&hidg_ida, minor);
1179 }
1180
hidg_free_inst(struct usb_function_instance * f)1181 static void hidg_free_inst(struct usb_function_instance *f)
1182 {
1183 struct f_hid_opts *opts;
1184
1185 opts = container_of(f, struct f_hid_opts, func_inst);
1186
1187 mutex_lock(&hidg_ida_lock);
1188
1189 hidg_put_minor(opts->minor);
1190 if (ida_is_empty(&hidg_ida))
1191 ghid_cleanup();
1192
1193 mutex_unlock(&hidg_ida_lock);
1194
1195 if (opts->report_desc_alloc)
1196 kfree(opts->report_desc);
1197
1198 kfree(opts);
1199 }
1200
hidg_alloc_inst(void)1201 static struct usb_function_instance *hidg_alloc_inst(void)
1202 {
1203 struct f_hid_opts *opts;
1204 struct usb_function_instance *ret;
1205 int status = 0;
1206
1207 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1208 if (!opts)
1209 return ERR_PTR(-ENOMEM);
1210 mutex_init(&opts->lock);
1211 opts->func_inst.free_func_inst = hidg_free_inst;
1212 ret = &opts->func_inst;
1213
1214 mutex_lock(&hidg_ida_lock);
1215
1216 if (ida_is_empty(&hidg_ida)) {
1217 status = ghid_setup(NULL, HIDG_MINORS);
1218 if (status) {
1219 ret = ERR_PTR(status);
1220 kfree(opts);
1221 goto unlock;
1222 }
1223 }
1224
1225 opts->minor = hidg_get_minor();
1226 if (opts->minor < 0) {
1227 ret = ERR_PTR(opts->minor);
1228 kfree(opts);
1229 if (ida_is_empty(&hidg_ida))
1230 ghid_cleanup();
1231 goto unlock;
1232 }
1233 config_group_init_type_name(&opts->func_inst.group, "", &hid_func_type);
1234
1235 unlock:
1236 mutex_unlock(&hidg_ida_lock);
1237 return ret;
1238 }
1239
hidg_free(struct usb_function * f)1240 static void hidg_free(struct usb_function *f)
1241 {
1242 struct f_hidg *hidg;
1243 struct f_hid_opts *opts;
1244
1245 hidg = func_to_hidg(f);
1246 opts = container_of(f->fi, struct f_hid_opts, func_inst);
1247 put_device(&hidg->dev);
1248 mutex_lock(&opts->lock);
1249 --opts->refcnt;
1250 mutex_unlock(&opts->lock);
1251 }
1252
hidg_unbind(struct usb_configuration * c,struct usb_function * f)1253 static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
1254 {
1255 struct f_hidg *hidg = func_to_hidg(f);
1256
1257 cdev_device_del(&hidg->cdev, &hidg->dev);
1258
1259 usb_free_all_descriptors(f);
1260 }
1261
hidg_alloc(struct usb_function_instance * fi)1262 static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
1263 {
1264 struct f_hidg *hidg;
1265 struct f_hid_opts *opts;
1266 int ret;
1267
1268 /* allocate and initialize one new instance */
1269 hidg = kzalloc(sizeof(*hidg), GFP_KERNEL);
1270 if (!hidg)
1271 return ERR_PTR(-ENOMEM);
1272
1273 opts = container_of(fi, struct f_hid_opts, func_inst);
1274
1275 mutex_lock(&opts->lock);
1276
1277 device_initialize(&hidg->dev);
1278 hidg->dev.release = hidg_release;
1279 hidg->dev.class = &hidg_class;
1280 hidg->dev.devt = MKDEV(major, opts->minor);
1281 ret = dev_set_name(&hidg->dev, "hidg%d", opts->minor);
1282 if (ret)
1283 goto err_unlock;
1284
1285 hidg->bInterfaceSubClass = opts->subclass;
1286 hidg->bInterfaceProtocol = opts->protocol;
1287 hidg->report_length = opts->report_length;
1288 hidg->report_desc_length = opts->report_desc_length;
1289 if (opts->report_desc) {
1290 hidg->report_desc = devm_kmemdup(&hidg->dev, opts->report_desc,
1291 opts->report_desc_length,
1292 GFP_KERNEL);
1293 if (!hidg->report_desc) {
1294 ret = -ENOMEM;
1295 goto err_put_device;
1296 }
1297 }
1298 hidg->use_out_ep = !opts->no_out_endpoint;
1299
1300 ++opts->refcnt;
1301 mutex_unlock(&opts->lock);
1302
1303 hidg->func.name = "hid";
1304 hidg->func.bind = hidg_bind;
1305 hidg->func.unbind = hidg_unbind;
1306 hidg->func.set_alt = hidg_set_alt;
1307 hidg->func.disable = hidg_disable;
1308 hidg->func.setup = hidg_setup;
1309 hidg->func.free_func = hidg_free;
1310
1311 /* this could be made configurable at some point */
1312 hidg->qlen = 4;
1313
1314 return &hidg->func;
1315
1316 err_put_device:
1317 put_device(&hidg->dev);
1318 err_unlock:
1319 mutex_unlock(&opts->lock);
1320 return ERR_PTR(ret);
1321 }
1322
1323 DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc);
1324 MODULE_LICENSE("GPL");
1325 MODULE_AUTHOR("Fabien Chouteau");
1326
ghid_setup(struct usb_gadget * g,int count)1327 int ghid_setup(struct usb_gadget *g, int count)
1328 {
1329 int status;
1330 dev_t dev;
1331
1332 status = class_register(&hidg_class);
1333 if (status)
1334 return status;
1335
1336 status = alloc_chrdev_region(&dev, 0, count, "hidg");
1337 if (status) {
1338 class_unregister(&hidg_class);
1339 return status;
1340 }
1341
1342 major = MAJOR(dev);
1343 minors = count;
1344
1345 return 0;
1346 }
1347
ghid_cleanup(void)1348 void ghid_cleanup(void)
1349 {
1350 if (major) {
1351 unregister_chrdev_region(MKDEV(major, 0), minors);
1352 major = minors = 0;
1353 }
1354
1355 class_unregister(&hidg_class);
1356 }
1357
