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Linux 4.2.1
[linux/fpc-iii.git] / drivers / usb / gadget / function / f_hid.c
blob6df9715a4bcd31179cb190100df45b2dd975a0d2
1 /*
2 * f_hid.c -- USB HID function driver
3 *
4 * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/hid.h>
15 #include <linux/idr.h>
16 #include <linux/cdev.h>
17 #include <linux/mutex.h>
18 #include <linux/poll.h>
19 #include <linux/uaccess.h>
20 #include <linux/wait.h>
21 #include <linux/sched.h>
22 #include <linux/usb/g_hid.h>
23
24 #include "u_f.h"
25 #include "u_hid.h"
26
27 #define HIDG_MINORS 4
28
29 static int major, minors;
30 static struct class *hidg_class;
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 short report_desc_length;
48 char *report_desc;
49 unsigned short report_length;
50
51 /* recv report */
52 struct list_head completed_out_req;
53 spinlock_t spinlock;
54 wait_queue_head_t read_queue;
55 unsigned int qlen;
56
57 /* send report */
58 struct mutex lock;
59 bool write_pending;
60 wait_queue_head_t write_queue;
61 struct usb_request *req;
62
63 int minor;
64 struct cdev cdev;
65 struct usb_function func;
66
67 struct usb_ep *in_ep;
68 struct usb_ep *out_ep;
69 };
70
71 static inline struct f_hidg *func_to_hidg(struct usb_function *f)
72 {
73 return container_of(f, struct f_hidg, func);
74 }
75
76 /*-------------------------------------------------------------------------*/
77 /* Static descriptors */
78
79 static struct usb_interface_descriptor hidg_interface_desc = {
80 .bLength = sizeof hidg_interface_desc,
81 .bDescriptorType = USB_DT_INTERFACE,
82 /* .bInterfaceNumber = DYNAMIC */
83 .bAlternateSetting = 0,
84 .bNumEndpoints = 2,
85 .bInterfaceClass = USB_CLASS_HID,
86 /* .bInterfaceSubClass = DYNAMIC */
87 /* .bInterfaceProtocol = DYNAMIC */
88 /* .iInterface = DYNAMIC */
89 };
90
91 static struct hid_descriptor hidg_desc = {
92 .bLength = sizeof hidg_desc,
93 .bDescriptorType = HID_DT_HID,
94 .bcdHID = 0x0101,
95 .bCountryCode = 0x00,
96 .bNumDescriptors = 0x1,
97 /*.desc[0].bDescriptorType = DYNAMIC */
98 /*.desc[0].wDescriptorLenght = DYNAMIC */
99 };
100
101 /* High-Speed Support */
102
103 static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
104 .bLength = USB_DT_ENDPOINT_SIZE,
105 .bDescriptorType = USB_DT_ENDPOINT,
106 .bEndpointAddress = USB_DIR_IN,
107 .bmAttributes = USB_ENDPOINT_XFER_INT,
108 /*.wMaxPacketSize = DYNAMIC */
109 .bInterval = 4, /* FIXME: Add this field in the
110 * HID gadget configuration?
111 * (struct hidg_func_descriptor)
112 */
113 };
114
115 static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = {
116 .bLength = USB_DT_ENDPOINT_SIZE,
117 .bDescriptorType = USB_DT_ENDPOINT,
118 .bEndpointAddress = USB_DIR_OUT,
119 .bmAttributes = USB_ENDPOINT_XFER_INT,
120 /*.wMaxPacketSize = DYNAMIC */
121 .bInterval = 4, /* FIXME: Add this field in the
122 * HID gadget configuration?
123 * (struct hidg_func_descriptor)
124 */
125 };
126
127 static struct usb_descriptor_header *hidg_hs_descriptors[] = {
128 (struct usb_descriptor_header *)&hidg_interface_desc,
129 (struct usb_descriptor_header *)&hidg_desc,
130 (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
131 (struct usb_descriptor_header *)&hidg_hs_out_ep_desc,
132 NULL,
133 };
134
135 /* Full-Speed Support */
136
137 static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
138 .bLength = USB_DT_ENDPOINT_SIZE,
139 .bDescriptorType = USB_DT_ENDPOINT,
140 .bEndpointAddress = USB_DIR_IN,
141 .bmAttributes = USB_ENDPOINT_XFER_INT,
142 /*.wMaxPacketSize = DYNAMIC */
143 .bInterval = 10, /* FIXME: Add this field in the
144 * HID gadget configuration?
145 * (struct hidg_func_descriptor)
146 */
147 };
148
149 static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = {
150 .bLength = USB_DT_ENDPOINT_SIZE,
151 .bDescriptorType = USB_DT_ENDPOINT,
152 .bEndpointAddress = USB_DIR_OUT,
153 .bmAttributes = USB_ENDPOINT_XFER_INT,
154 /*.wMaxPacketSize = DYNAMIC */
155 .bInterval = 10, /* FIXME: Add this field in the
156 * HID gadget configuration?
157 * (struct hidg_func_descriptor)
158 */
159 };
160
161 static struct usb_descriptor_header *hidg_fs_descriptors[] = {
162 (struct usb_descriptor_header *)&hidg_interface_desc,
163 (struct usb_descriptor_header *)&hidg_desc,
164 (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
165 (struct usb_descriptor_header *)&hidg_fs_out_ep_desc,
166 NULL,
167 };
168
169 /*-------------------------------------------------------------------------*/
170 /* Strings */
171
172 #define CT_FUNC_HID_IDX 0
173
174 static struct usb_string ct_func_string_defs[] = {
175 [CT_FUNC_HID_IDX].s = "HID Interface",
176 {}, /* end of list */
177 };
178
179 static struct usb_gadget_strings ct_func_string_table = {
180 .language = 0x0409, /* en-US */
181 .strings = ct_func_string_defs,
182 };
183
184 static struct usb_gadget_strings *ct_func_strings[] = {
185 &ct_func_string_table,
186 NULL,
187 };
188
189 /*-------------------------------------------------------------------------*/
190 /* Char Device */
191
192 static ssize_t f_hidg_read(struct file *file, char __user *buffer,
193 size_t count, loff_t *ptr)
194 {
195 struct f_hidg *hidg = file->private_data;
196 struct f_hidg_req_list *list;
197 struct usb_request *req;
198 unsigned long flags;
199 int ret;
200
201 if (!count)
202 return 0;
203
204 if (!access_ok(VERIFY_WRITE, buffer, count))
205 return -EFAULT;
206
207 spin_lock_irqsave(&hidg->spinlock, flags);
208
209 #define READ_COND (!list_empty(&hidg->completed_out_req))
210
211 /* wait for at least one buffer to complete */
212 while (!READ_COND) {
213 spin_unlock_irqrestore(&hidg->spinlock, flags);
214 if (file->f_flags & O_NONBLOCK)
215 return -EAGAIN;
216
217 if (wait_event_interruptible(hidg->read_queue, READ_COND))
218 return -ERESTARTSYS;
219
220 spin_lock_irqsave(&hidg->spinlock, flags);
221 }
222
223 /* pick the first one */
224 list = list_first_entry(&hidg->completed_out_req,
225 struct f_hidg_req_list, list);
226 req = list->req;
227 count = min_t(unsigned int, count, req->actual - list->pos);
228 spin_unlock_irqrestore(&hidg->spinlock, flags);
229
230 /* copy to user outside spinlock */
231 count -= copy_to_user(buffer, req->buf + list->pos, count);
232 list->pos += count;
233
234 /*
235 * if this request is completely handled and transfered to
236 * userspace, remove its entry from the list and requeue it
237 * again. Otherwise, we will revisit it again upon the next
238 * call, taking into account its current read position.
239 */
240 if (list->pos == req->actual) {
241 spin_lock_irqsave(&hidg->spinlock, flags);
242 list_del(&list->list);
243 kfree(list);
244 spin_unlock_irqrestore(&hidg->spinlock, flags);
245
246 req->length = hidg->report_length;
247 ret = usb_ep_queue(hidg->out_ep, req, GFP_KERNEL);
248 if (ret < 0)
249 return ret;
250 }
251
252 return count;
253 }
254
255 static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
256 {
257 struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
258
259 if (req->status != 0) {
260 ERROR(hidg->func.config->cdev,
261 "End Point Request ERROR: %d\n", req->status);
262 }
263
264 hidg->write_pending = 0;
265 wake_up(&hidg->write_queue);
266 }
267
268 static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
269 size_t count, loff_t *offp)
270 {
271 struct f_hidg *hidg = file->private_data;
272 ssize_t status = -ENOMEM;
273
274 if (!access_ok(VERIFY_READ, buffer, count))
275 return -EFAULT;
276
277 mutex_lock(&hidg->lock);
278
279 #define WRITE_COND (!hidg->write_pending)
280
281 /* write queue */
282 while (!WRITE_COND) {
283 mutex_unlock(&hidg->lock);
284 if (file->f_flags & O_NONBLOCK)
285 return -EAGAIN;
286
287 if (wait_event_interruptible_exclusive(
288 hidg->write_queue, WRITE_COND))
289 return -ERESTARTSYS;
290
291 mutex_lock(&hidg->lock);
292 }
293
294 count = min_t(unsigned, count, hidg->report_length);
295 status = copy_from_user(hidg->req->buf, buffer, count);
296
297 if (status != 0) {
298 ERROR(hidg->func.config->cdev,
299 "copy_from_user error\n");
300 mutex_unlock(&hidg->lock);
301 return -EINVAL;
302 }
303
304 hidg->req->status = 0;
305 hidg->req->zero = 0;
306 hidg->req->length = count;
307 hidg->req->complete = f_hidg_req_complete;
308 hidg->req->context = hidg;
309 hidg->write_pending = 1;
310
311 status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC);
312 if (status < 0) {
313 ERROR(hidg->func.config->cdev,
314 "usb_ep_queue error on int endpoint %zd\n", status);
315 hidg->write_pending = 0;
316 wake_up(&hidg->write_queue);
317 } else {
318 status = count;
319 }
320
321 mutex_unlock(&hidg->lock);
322
323 return status;
324 }
325
326 static unsigned int f_hidg_poll(struct file *file, poll_table *wait)
327 {
328 struct f_hidg *hidg = file->private_data;
329 unsigned int ret = 0;
330
331 poll_wait(file, &hidg->read_queue, wait);
332 poll_wait(file, &hidg->write_queue, wait);
333
334 if (WRITE_COND)
335 ret |= POLLOUT | POLLWRNORM;
336
337 if (READ_COND)
338 ret |= POLLIN | POLLRDNORM;
339
340 return ret;
341 }
342
343 #undef WRITE_COND
344 #undef READ_COND
345
346 static int f_hidg_release(struct inode *inode, struct file *fd)
347 {
348 fd->private_data = NULL;
349 return 0;
350 }
351
352 static int f_hidg_open(struct inode *inode, struct file *fd)
353 {
354 struct f_hidg *hidg =
355 container_of(inode->i_cdev, struct f_hidg, cdev);
356
357 fd->private_data = hidg;
358
359 return 0;
360 }
361
362 /*-------------------------------------------------------------------------*/
363 /* usb_function */
364
365 static inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep,
366 unsigned length)
367 {
368 return alloc_ep_req(ep, length, length);
369 }
370
371 static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
372 {
373 struct f_hidg *hidg = (struct f_hidg *) req->context;
374 struct f_hidg_req_list *req_list;
375 unsigned long flags;
376
377 req_list = kzalloc(sizeof(*req_list), GFP_ATOMIC);
378 if (!req_list)
379 return;
380
381 req_list->req = req;
382
383 spin_lock_irqsave(&hidg->spinlock, flags);
384 list_add_tail(&req_list->list, &hidg->completed_out_req);
385 spin_unlock_irqrestore(&hidg->spinlock, flags);
386
387 wake_up(&hidg->read_queue);
388 }
389
390 static int hidg_setup(struct usb_function *f,
391 const struct usb_ctrlrequest *ctrl)
392 {
393 struct f_hidg *hidg = func_to_hidg(f);
394 struct usb_composite_dev *cdev = f->config->cdev;
395 struct usb_request *req = cdev->req;
396 int status = 0;
397 __u16 value, length;
398
399 value = __le16_to_cpu(ctrl->wValue);
400 length = __le16_to_cpu(ctrl->wLength);
401
402 VDBG(cdev,
403 "%s crtl_request : bRequestType:0x%x bRequest:0x%x Value:0x%x\n",
404 __func__, ctrl->bRequestType, ctrl->bRequest, value);
405
406 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
407 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
408 | HID_REQ_GET_REPORT):
409 VDBG(cdev, "get_report\n");
410
411 /* send an empty report */
412 length = min_t(unsigned, length, hidg->report_length);
413 memset(req->buf, 0x0, length);
414
415 goto respond;
416 break;
417
418 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
419 | HID_REQ_GET_PROTOCOL):
420 VDBG(cdev, "get_protocol\n");
421 goto stall;
422 break;
423
424 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
425 | HID_REQ_SET_REPORT):
426 VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength);
427 goto stall;
428 break;
429
430 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
431 | HID_REQ_SET_PROTOCOL):
432 VDBG(cdev, "set_protocol\n");
433 goto stall;
434 break;
435
436 case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
437 | USB_REQ_GET_DESCRIPTOR):
438 switch (value >> 8) {
439 case HID_DT_HID:
440 {
441 struct hid_descriptor hidg_desc_copy = hidg_desc;
442
443 VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n");
444 hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT;
445 hidg_desc_copy.desc[0].wDescriptorLength =
446 cpu_to_le16(hidg->report_desc_length);
447
448 length = min_t(unsigned short, length,
449 hidg_desc_copy.bLength);
450 memcpy(req->buf, &hidg_desc_copy, length);
451 goto respond;
452 break;
453 }
454 case HID_DT_REPORT:
455 VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
456 length = min_t(unsigned short, length,
457 hidg->report_desc_length);
458 memcpy(req->buf, hidg->report_desc, length);
459 goto respond;
460 break;
461
462 default:
463 VDBG(cdev, "Unknown descriptor request 0x%x\n",
464 value >> 8);
465 goto stall;
466 break;
467 }
468 break;
469
470 default:
471 VDBG(cdev, "Unknown request 0x%x\n",
472 ctrl->bRequest);
473 goto stall;
474 break;
475 }
476
477 stall:
478 return -EOPNOTSUPP;
479
480 respond:
481 req->zero = 0;
482 req->length = length;
483 status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
484 if (status < 0)
485 ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
486 return status;
487 }
488
489 static void hidg_disable(struct usb_function *f)
490 {
491 struct f_hidg *hidg = func_to_hidg(f);
492 struct f_hidg_req_list *list, *next;
493
494 usb_ep_disable(hidg->in_ep);
495 hidg->in_ep->driver_data = NULL;
496
497 usb_ep_disable(hidg->out_ep);
498 hidg->out_ep->driver_data = NULL;
499
500 list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
501 list_del(&list->list);
502 kfree(list);
503 }
504 }
505
506 static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
507 {
508 struct usb_composite_dev *cdev = f->config->cdev;
509 struct f_hidg *hidg = func_to_hidg(f);
510 int i, status = 0;
511
512 VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);
513
514 if (hidg->in_ep != NULL) {
515 /* restart endpoint */
516 if (hidg->in_ep->driver_data != NULL)
517 usb_ep_disable(hidg->in_ep);
518
519 status = config_ep_by_speed(f->config->cdev->gadget, f,
520 hidg->in_ep);
521 if (status) {
522 ERROR(cdev, "config_ep_by_speed FAILED!\n");
523 goto fail;
524 }
525 status = usb_ep_enable(hidg->in_ep);
526 if (status < 0) {
527 ERROR(cdev, "Enable IN endpoint FAILED!\n");
528 goto fail;
529 }
530 hidg->in_ep->driver_data = hidg;
531 }
532
533
534 if (hidg->out_ep != NULL) {
535 /* restart endpoint */
536 if (hidg->out_ep->driver_data != NULL)
537 usb_ep_disable(hidg->out_ep);
538
539 status = config_ep_by_speed(f->config->cdev->gadget, f,
540 hidg->out_ep);
541 if (status) {
542 ERROR(cdev, "config_ep_by_speed FAILED!\n");
543 goto fail;
544 }
545 status = usb_ep_enable(hidg->out_ep);
546 if (status < 0) {
547 ERROR(cdev, "Enable IN endpoint FAILED!\n");
548 goto fail;
549 }
550 hidg->out_ep->driver_data = hidg;
551
552 /*
553 * allocate a bunch of read buffers and queue them all at once.
554 */
555 for (i = 0; i < hidg->qlen && status == 0; i++) {
556 struct usb_request *req =
557 hidg_alloc_ep_req(hidg->out_ep,
558 hidg->report_length);
559 if (req) {
560 req->complete = hidg_set_report_complete;
561 req->context = hidg;
562 status = usb_ep_queue(hidg->out_ep, req,
563 GFP_ATOMIC);
564 if (status)
565 ERROR(cdev, "%s queue req --> %d\n",
566 hidg->out_ep->name, status);
567 } else {
568 usb_ep_disable(hidg->out_ep);
569 hidg->out_ep->driver_data = NULL;
570 status = -ENOMEM;
571 goto fail;
572 }
573 }
574 }
575
576 fail:
577 return status;
578 }
579
580 static const struct file_operations f_hidg_fops = {
581 .owner = THIS_MODULE,
582 .open = f_hidg_open,
583 .release = f_hidg_release,
584 .write = f_hidg_write,
585 .read = f_hidg_read,
586 .poll = f_hidg_poll,
587 .llseek = noop_llseek,
588 };
589
590 static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
591 {
592 struct usb_ep *ep;
593 struct f_hidg *hidg = func_to_hidg(f);
594 struct usb_string *us;
595 struct device *device;
596 int status;
597 dev_t dev;
598
599 /* maybe allocate device-global string IDs, and patch descriptors */
600 us = usb_gstrings_attach(c->cdev, ct_func_strings,
601 ARRAY_SIZE(ct_func_string_defs));
602 if (IS_ERR(us))
603 return PTR_ERR(us);
604 hidg_interface_desc.iInterface = us[CT_FUNC_HID_IDX].id;
605
606 /* allocate instance-specific interface IDs, and patch descriptors */
607 status = usb_interface_id(c, f);
608 if (status < 0)
609 goto fail;
610 hidg_interface_desc.bInterfaceNumber = status;
611
612 /* allocate instance-specific endpoints */
613 status = -ENODEV;
614 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
615 if (!ep)
616 goto fail;
617 ep->driver_data = c->cdev; /* claim */
618 hidg->in_ep = ep;
619
620 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
621 if (!ep)
622 goto fail;
623 ep->driver_data = c->cdev; /* claim */
624 hidg->out_ep = ep;
625
626 /* preallocate request and buffer */
627 status = -ENOMEM;
628 hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
629 if (!hidg->req)
630 goto fail;
631
632 hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
633 if (!hidg->req->buf)
634 goto fail;
635
636 /* set descriptor dynamic values */
637 hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
638 hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
639 hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
640 hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
641 hidg_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
642 hidg_fs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
643 /*
644 * We can use hidg_desc struct here but we should not relay
645 * that its content won't change after returning from this function.
646 */
647 hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
648 hidg_desc.desc[0].wDescriptorLength =
649 cpu_to_le16(hidg->report_desc_length);
650
651 hidg_hs_in_ep_desc.bEndpointAddress =
652 hidg_fs_in_ep_desc.bEndpointAddress;
653 hidg_hs_out_ep_desc.bEndpointAddress =
654 hidg_fs_out_ep_desc.bEndpointAddress;
655
656 status = usb_assign_descriptors(f, hidg_fs_descriptors,
657 hidg_hs_descriptors, NULL);
658 if (status)
659 goto fail;
660
661 mutex_init(&hidg->lock);
662 spin_lock_init(&hidg->spinlock);
663 init_waitqueue_head(&hidg->write_queue);
664 init_waitqueue_head(&hidg->read_queue);
665 INIT_LIST_HEAD(&hidg->completed_out_req);
666
667 /* create char device */
668 cdev_init(&hidg->cdev, &f_hidg_fops);
669 dev = MKDEV(major, hidg->minor);
670 status = cdev_add(&hidg->cdev, dev, 1);
671 if (status)
672 goto fail_free_descs;
673
674 device = device_create(hidg_class, NULL, dev, NULL,
675 "%s%d", "hidg", hidg->minor);
676 if (IS_ERR(device)) {
677 status = PTR_ERR(device);
678 goto del;
679 }
680
681 return 0;
682 del:
683 cdev_del(&hidg->cdev);
684 fail_free_descs:
685 usb_free_all_descriptors(f);
686 fail:
687 ERROR(f->config->cdev, "hidg_bind FAILED\n");
688 if (hidg->req != NULL) {
689 kfree(hidg->req->buf);
690 if (hidg->in_ep != NULL)
691 usb_ep_free_request(hidg->in_ep, hidg->req);
692 }
693
694 return status;
695 }
696
697 static inline int hidg_get_minor(void)
698 {
699 int ret;
700
701 ret = ida_simple_get(&hidg_ida, 0, 0, GFP_KERNEL);
702 if (ret >= HIDG_MINORS) {
703 ida_simple_remove(&hidg_ida, ret);
704 ret = -ENODEV;
705 }
706
707 return ret;
708 }
709
710 static inline struct f_hid_opts *to_f_hid_opts(struct config_item *item)
711 {
712 return container_of(to_config_group(item), struct f_hid_opts,
713 func_inst.group);
714 }
715
716 CONFIGFS_ATTR_STRUCT(f_hid_opts);
717 CONFIGFS_ATTR_OPS(f_hid_opts);
718
719 static void hid_attr_release(struct config_item *item)
720 {
721 struct f_hid_opts *opts = to_f_hid_opts(item);
722
723 usb_put_function_instance(&opts->func_inst);
724 }
725
726 static struct configfs_item_operations hidg_item_ops = {
727 .release = hid_attr_release,
728 .show_attribute = f_hid_opts_attr_show,
729 .store_attribute = f_hid_opts_attr_store,
730 };
731
732 #define F_HID_OPT(name, prec, limit) \
733 static ssize_t f_hid_opts_##name##_show(struct f_hid_opts *opts, char *page)\
734 { \
735 int result; \
736 \
737 mutex_lock(&opts->lock); \
738 result = sprintf(page, "%d\n", opts->name); \
739 mutex_unlock(&opts->lock); \
740 \
741 return result; \
742 } \
743 \
744 static ssize_t f_hid_opts_##name##_store(struct f_hid_opts *opts, \
745 const char *page, size_t len) \
746 { \
747 int ret; \
748 u##prec num; \
749 \
750 mutex_lock(&opts->lock); \
751 if (opts->refcnt) { \
752 ret = -EBUSY; \
753 goto end; \
754 } \
755 \
756 ret = kstrtou##prec(page, 0, &num); \
757 if (ret) \
758 goto end; \
759 \
760 if (num > limit) { \
761 ret = -EINVAL; \
762 goto end; \
763 } \
764 opts->name = num; \
765 ret = len; \
766 \
767 end: \
768 mutex_unlock(&opts->lock); \
769 return ret; \
770 } \
771 \
772 static struct f_hid_opts_attribute f_hid_opts_##name = \
773 __CONFIGFS_ATTR(name, S_IRUGO | S_IWUSR, f_hid_opts_##name##_show,\
774 f_hid_opts_##name##_store)
775
776 F_HID_OPT(subclass, 8, 255);
777 F_HID_OPT(protocol, 8, 255);
778 F_HID_OPT(report_length, 16, 65535);
779
780 static ssize_t f_hid_opts_report_desc_show(struct f_hid_opts *opts, char *page)
781 {
782 int result;
783
784 mutex_lock(&opts->lock);
785 result = opts->report_desc_length;
786 memcpy(page, opts->report_desc, opts->report_desc_length);
787 mutex_unlock(&opts->lock);
788
789 return result;
790 }
791
792 static ssize_t f_hid_opts_report_desc_store(struct f_hid_opts *opts,
793 const char *page, size_t len)
794 {
795 int ret = -EBUSY;
796 char *d;
797
798 mutex_lock(&opts->lock);
799
800 if (opts->refcnt)
801 goto end;
802 if (len > PAGE_SIZE) {
803 ret = -ENOSPC;
804 goto end;
805 }
806 d = kmemdup(page, len, GFP_KERNEL);
807 if (!d) {
808 ret = -ENOMEM;
809 goto end;
810 }
811 kfree(opts->report_desc);
812 opts->report_desc = d;
813 opts->report_desc_length = len;
814 opts->report_desc_alloc = true;
815 ret = len;
816 end:
817 mutex_unlock(&opts->lock);
818 return ret;
819 }
820
821 static struct f_hid_opts_attribute f_hid_opts_report_desc =
822 __CONFIGFS_ATTR(report_desc, S_IRUGO | S_IWUSR,
823 f_hid_opts_report_desc_show,
824 f_hid_opts_report_desc_store);
825
826 static struct configfs_attribute *hid_attrs[] = {
827 &f_hid_opts_subclass.attr,
828 &f_hid_opts_protocol.attr,
829 &f_hid_opts_report_length.attr,
830 &f_hid_opts_report_desc.attr,
831 NULL,
832 };
833
834 static struct config_item_type hid_func_type = {
835 .ct_item_ops = &hidg_item_ops,
836 .ct_attrs = hid_attrs,
837 .ct_owner = THIS_MODULE,
838 };
839
840 static inline void hidg_put_minor(int minor)
841 {
842 ida_simple_remove(&hidg_ida, minor);
843 }
844
845 static void hidg_free_inst(struct usb_function_instance *f)
846 {
847 struct f_hid_opts *opts;
848
849 opts = container_of(f, struct f_hid_opts, func_inst);
850
851 mutex_lock(&hidg_ida_lock);
852
853 hidg_put_minor(opts->minor);
854 if (idr_is_empty(&hidg_ida.idr))
855 ghid_cleanup();
856
857 mutex_unlock(&hidg_ida_lock);
858
859 if (opts->report_desc_alloc)
860 kfree(opts->report_desc);
861
862 kfree(opts);
863 }
864
865 static struct usb_function_instance *hidg_alloc_inst(void)
866 {
867 struct f_hid_opts *opts;
868 struct usb_function_instance *ret;
869 int status = 0;
870
871 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
872 if (!opts)
873 return ERR_PTR(-ENOMEM);
874 mutex_init(&opts->lock);
875 opts->func_inst.free_func_inst = hidg_free_inst;
876 ret = &opts->func_inst;
877
878 mutex_lock(&hidg_ida_lock);
879
880 if (idr_is_empty(&hidg_ida.idr)) {
881 status = ghid_setup(NULL, HIDG_MINORS);
882 if (status) {
883 ret = ERR_PTR(status);
884 kfree(opts);
885 goto unlock;
886 }
887 }
888
889 opts->minor = hidg_get_minor();
890 if (opts->minor < 0) {
891 ret = ERR_PTR(opts->minor);
892 kfree(opts);
893 if (idr_is_empty(&hidg_ida.idr))
894 ghid_cleanup();
895 goto unlock;
896 }
897 config_group_init_type_name(&opts->func_inst.group, "", &hid_func_type);
898
899 unlock:
900 mutex_unlock(&hidg_ida_lock);
901 return ret;
902 }
903
904 static void hidg_free(struct usb_function *f)
905 {
906 struct f_hidg *hidg;
907 struct f_hid_opts *opts;
908
909 hidg = func_to_hidg(f);
910 opts = container_of(f->fi, struct f_hid_opts, func_inst);
911 kfree(hidg->report_desc);
912 kfree(hidg);
913 mutex_lock(&opts->lock);
914 --opts->refcnt;
915 mutex_unlock(&opts->lock);
916 }
917
918 static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
919 {
920 struct f_hidg *hidg = func_to_hidg(f);
921
922 device_destroy(hidg_class, MKDEV(major, hidg->minor));
923 cdev_del(&hidg->cdev);
924
925 /* disable/free request and end point */
926 usb_ep_disable(hidg->in_ep);
927 kfree(hidg->req->buf);
928 usb_ep_free_request(hidg->in_ep, hidg->req);
929
930 usb_free_all_descriptors(f);
931 }
932
933 static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
934 {
935 struct f_hidg *hidg;
936 struct f_hid_opts *opts;
937
938 /* allocate and initialize one new instance */
939 hidg = kzalloc(sizeof(*hidg), GFP_KERNEL);
940 if (!hidg)
941 return ERR_PTR(-ENOMEM);
942
943 opts = container_of(fi, struct f_hid_opts, func_inst);
944
945 mutex_lock(&opts->lock);
946 ++opts->refcnt;
947
948 hidg->minor = opts->minor;
949 hidg->bInterfaceSubClass = opts->subclass;
950 hidg->bInterfaceProtocol = opts->protocol;
951 hidg->report_length = opts->report_length;
952 hidg->report_desc_length = opts->report_desc_length;
953 if (opts->report_desc) {
954 hidg->report_desc = kmemdup(opts->report_desc,
955 opts->report_desc_length,
956 GFP_KERNEL);
957 if (!hidg->report_desc) {
958 kfree(hidg);
959 mutex_unlock(&opts->lock);
960 return ERR_PTR(-ENOMEM);
961 }
962 }
963
964 mutex_unlock(&opts->lock);
965
966 hidg->func.name = "hid";
967 hidg->func.bind = hidg_bind;
968 hidg->func.unbind = hidg_unbind;
969 hidg->func.set_alt = hidg_set_alt;
970 hidg->func.disable = hidg_disable;
971 hidg->func.setup = hidg_setup;
972 hidg->func.free_func = hidg_free;
973
974 /* this could me made configurable at some point */
975 hidg->qlen = 4;
976
977 return &hidg->func;
978 }
979
980 DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc);
981 MODULE_LICENSE("GPL");
982 MODULE_AUTHOR("Fabien Chouteau");
983
984 int ghid_setup(struct usb_gadget *g, int count)
985 {
986 int status;
987 dev_t dev;
988
989 hidg_class = class_create(THIS_MODULE, "hidg");
990 if (IS_ERR(hidg_class)) {
991 status = PTR_ERR(hidg_class);
992 hidg_class = NULL;
993 return status;
994 }
995
996 status = alloc_chrdev_region(&dev, 0, count, "hidg");
997 if (status) {
998 class_destroy(hidg_class);
999 hidg_class = NULL;
1000 return status;
1001 }
1002
1003 major = MAJOR(dev);
1004 minors = count;
1005
1006 return 0;
1007 }
1008
1009 void ghid_cleanup(void)
1010 {
1011 if (major) {
1012 unregister_chrdev_region(MKDEV(major, 0), minors);
1013 major = minors = 0;
1014 }
1015
1016 class_destroy(hidg_class);
1017 hidg_class = NULL;
1018 }
Linux with added FPC-III support