blob: 53e120208e990c5a423b76dfa5578b5991aabf17 [file] [log] [blame]
Fabien Chouteau71adf112010-04-08 09:31:15 +02001/*
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 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/kernel.h>
22#include <linux/utsname.h>
23#include <linux/module.h>
24#include <linux/hid.h>
25#include <linux/cdev.h>
26#include <linux/mutex.h>
27#include <linux/poll.h>
28#include <linux/smp_lock.h>
29#include <linux/uaccess.h>
30#include <linux/wait.h>
31#include <linux/usb/g_hid.h>
32
33static int major, minors;
34static struct class *hidg_class;
35
36/*-------------------------------------------------------------------------*/
37/* HID gadget struct */
38
39struct f_hidg {
40 /* configuration */
41 unsigned char bInterfaceSubClass;
42 unsigned char bInterfaceProtocol;
43 unsigned short report_desc_length;
44 char *report_desc;
45 unsigned short report_length;
46
47 /* recv report */
48 char *set_report_buff;
49 unsigned short set_report_length;
50 spinlock_t spinlock;
51 wait_queue_head_t read_queue;
52
53 /* send report */
54 struct mutex lock;
55 bool write_pending;
56 wait_queue_head_t write_queue;
57 struct usb_request *req;
58
59 int minor;
60 struct cdev cdev;
61 struct usb_function func;
62 struct usb_ep *in_ep;
63 struct usb_endpoint_descriptor *fs_in_ep_desc;
64 struct usb_endpoint_descriptor *hs_in_ep_desc;
65};
66
67static inline struct f_hidg *func_to_hidg(struct usb_function *f)
68{
69 return container_of(f, struct f_hidg, func);
70}
71
72/*-------------------------------------------------------------------------*/
73/* Static descriptors */
74
75static struct usb_interface_descriptor hidg_interface_desc = {
76 .bLength = sizeof hidg_interface_desc,
77 .bDescriptorType = USB_DT_INTERFACE,
78 /* .bInterfaceNumber = DYNAMIC */
79 .bAlternateSetting = 0,
80 .bNumEndpoints = 1,
81 .bInterfaceClass = USB_CLASS_HID,
82 /* .bInterfaceSubClass = DYNAMIC */
83 /* .bInterfaceProtocol = DYNAMIC */
84 /* .iInterface = DYNAMIC */
85};
86
87static struct hid_descriptor hidg_desc = {
88 .bLength = sizeof hidg_desc,
89 .bDescriptorType = HID_DT_HID,
90 .bcdHID = 0x0101,
91 .bCountryCode = 0x00,
92 .bNumDescriptors = 0x1,
93 /*.desc[0].bDescriptorType = DYNAMIC */
94 /*.desc[0].wDescriptorLenght = DYNAMIC */
95};
96
97/* High-Speed Support */
98
99static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
100 .bLength = USB_DT_ENDPOINT_SIZE,
101 .bDescriptorType = USB_DT_ENDPOINT,
102 .bEndpointAddress = USB_DIR_IN,
103 .bmAttributes = USB_ENDPOINT_XFER_INT,
104 /*.wMaxPacketSize = DYNAMIC */
105 .bInterval = 4, /* FIXME: Add this field in the
106 * HID gadget configuration?
107 * (struct hidg_func_descriptor)
108 */
109};
110
111static struct usb_descriptor_header *hidg_hs_descriptors[] = {
112 (struct usb_descriptor_header *)&hidg_interface_desc,
113 (struct usb_descriptor_header *)&hidg_desc,
114 (struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
115 NULL,
116};
117
118/* Full-Speed Support */
119
120static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
121 .bLength = USB_DT_ENDPOINT_SIZE,
122 .bDescriptorType = USB_DT_ENDPOINT,
123 .bEndpointAddress = USB_DIR_IN,
124 .bmAttributes = USB_ENDPOINT_XFER_INT,
125 /*.wMaxPacketSize = DYNAMIC */
126 .bInterval = 10, /* FIXME: Add this field in the
127 * HID gadget configuration?
128 * (struct hidg_func_descriptor)
129 */
130};
131
132static struct usb_descriptor_header *hidg_fs_descriptors[] = {
133 (struct usb_descriptor_header *)&hidg_interface_desc,
134 (struct usb_descriptor_header *)&hidg_desc,
135 (struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
136 NULL,
137};
138
139/*-------------------------------------------------------------------------*/
140/* Char Device */
141
142static ssize_t f_hidg_read(struct file *file, char __user *buffer,
143 size_t count, loff_t *ptr)
144{
Joe Perchesfd63b102010-07-12 13:50:11 -0700145 struct f_hidg *hidg = file->private_data;
Fabien Chouteau71adf112010-04-08 09:31:15 +0200146 char *tmp_buff = NULL;
147 unsigned long flags;
148
149 if (!count)
150 return 0;
151
152 if (!access_ok(VERIFY_WRITE, buffer, count))
153 return -EFAULT;
154
155 spin_lock_irqsave(&hidg->spinlock, flags);
156
157#define READ_COND (hidg->set_report_buff != NULL)
158
159 while (!READ_COND) {
160 spin_unlock_irqrestore(&hidg->spinlock, flags);
161 if (file->f_flags & O_NONBLOCK)
162 return -EAGAIN;
163
164 if (wait_event_interruptible(hidg->read_queue, READ_COND))
165 return -ERESTARTSYS;
166
167 spin_lock_irqsave(&hidg->spinlock, flags);
168 }
169
170
171 count = min_t(unsigned, count, hidg->set_report_length);
172 tmp_buff = hidg->set_report_buff;
173 hidg->set_report_buff = NULL;
174
175 spin_unlock_irqrestore(&hidg->spinlock, flags);
176
177 if (tmp_buff != NULL) {
178 /* copy to user outside spinlock */
179 count -= copy_to_user(buffer, tmp_buff, count);
180 kfree(tmp_buff);
181 } else
182 count = -ENOMEM;
183
184 return count;
185}
186
187static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
188{
189 struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
190
191 if (req->status != 0) {
192 ERROR(hidg->func.config->cdev,
193 "End Point Request ERROR: %d\n", req->status);
194 }
195
196 hidg->write_pending = 0;
197 wake_up(&hidg->write_queue);
198}
199
200static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
201 size_t count, loff_t *offp)
202{
Joe Perchesfd63b102010-07-12 13:50:11 -0700203 struct f_hidg *hidg = file->private_data;
Fabien Chouteau71adf112010-04-08 09:31:15 +0200204 ssize_t status = -ENOMEM;
205
206 if (!access_ok(VERIFY_READ, buffer, count))
207 return -EFAULT;
208
209 mutex_lock(&hidg->lock);
210
211#define WRITE_COND (!hidg->write_pending)
212
213 /* write queue */
214 while (!WRITE_COND) {
215 mutex_unlock(&hidg->lock);
216 if (file->f_flags & O_NONBLOCK)
217 return -EAGAIN;
218
219 if (wait_event_interruptible_exclusive(
220 hidg->write_queue, WRITE_COND))
221 return -ERESTARTSYS;
222
223 mutex_lock(&hidg->lock);
224 }
225
226 count = min_t(unsigned, count, hidg->report_length);
227 status = copy_from_user(hidg->req->buf, buffer, count);
228
229 if (status != 0) {
230 ERROR(hidg->func.config->cdev,
231 "copy_from_user error\n");
232 mutex_unlock(&hidg->lock);
233 return -EINVAL;
234 }
235
236 hidg->req->status = 0;
237 hidg->req->zero = 0;
238 hidg->req->length = count;
239 hidg->req->complete = f_hidg_req_complete;
240 hidg->req->context = hidg;
241 hidg->write_pending = 1;
242
243 status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC);
244 if (status < 0) {
245 ERROR(hidg->func.config->cdev,
246 "usb_ep_queue error on int endpoint %zd\n", status);
247 hidg->write_pending = 0;
248 wake_up(&hidg->write_queue);
249 } else {
250 status = count;
251 }
252
253 mutex_unlock(&hidg->lock);
254
255 return status;
256}
257
258static unsigned int f_hidg_poll(struct file *file, poll_table *wait)
259{
Joe Perchesfd63b102010-07-12 13:50:11 -0700260 struct f_hidg *hidg = file->private_data;
Fabien Chouteau71adf112010-04-08 09:31:15 +0200261 unsigned int ret = 0;
262
263 poll_wait(file, &hidg->read_queue, wait);
264 poll_wait(file, &hidg->write_queue, wait);
265
266 if (WRITE_COND)
267 ret |= POLLOUT | POLLWRNORM;
268
269 if (READ_COND)
270 ret |= POLLIN | POLLRDNORM;
271
272 return ret;
273}
274
275#undef WRITE_COND
276#undef READ_COND
277
278static int f_hidg_release(struct inode *inode, struct file *fd)
279{
280 fd->private_data = NULL;
281 return 0;
282}
283
284static int f_hidg_open(struct inode *inode, struct file *fd)
285{
286 struct f_hidg *hidg =
287 container_of(inode->i_cdev, struct f_hidg, cdev);
288
289 fd->private_data = hidg;
290
291 return 0;
292}
293
294/*-------------------------------------------------------------------------*/
295/* usb_function */
296
297static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
298{
299 struct f_hidg *hidg = (struct f_hidg *)req->context;
300
301 if (req->status != 0 || req->buf == NULL || req->actual == 0) {
302 ERROR(hidg->func.config->cdev, "%s FAILED\n", __func__);
303 return;
304 }
305
306 spin_lock(&hidg->spinlock);
307
308 hidg->set_report_buff = krealloc(hidg->set_report_buff,
309 req->actual, GFP_ATOMIC);
310
311 if (hidg->set_report_buff == NULL) {
312 spin_unlock(&hidg->spinlock);
313 return;
314 }
315 hidg->set_report_length = req->actual;
316 memcpy(hidg->set_report_buff, req->buf, req->actual);
317
318 spin_unlock(&hidg->spinlock);
319
320 wake_up(&hidg->read_queue);
321
322 return;
323}
324
325static int hidg_setup(struct usb_function *f,
326 const struct usb_ctrlrequest *ctrl)
327{
328 struct f_hidg *hidg = func_to_hidg(f);
329 struct usb_composite_dev *cdev = f->config->cdev;
330 struct usb_request *req = cdev->req;
331 int status = 0;
332 __u16 value, length;
333
334 value = __le16_to_cpu(ctrl->wValue);
335 length = __le16_to_cpu(ctrl->wLength);
336
337 VDBG(cdev, "hid_setup crtl_request : bRequestType:0x%x bRequest:0x%x "
338 "Value:0x%x\n", ctrl->bRequestType, ctrl->bRequest, value);
339
340 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
341 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
342 | HID_REQ_GET_REPORT):
343 VDBG(cdev, "get_report\n");
344
345 /* send an empty report */
346 length = min_t(unsigned, length, hidg->report_length);
347 memset(req->buf, 0x0, length);
348
349 goto respond;
350 break;
351
352 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
353 | HID_REQ_GET_PROTOCOL):
354 VDBG(cdev, "get_protocol\n");
355 goto stall;
356 break;
357
358 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
359 | HID_REQ_SET_REPORT):
360 VDBG(cdev, "set_report | wLenght=%d\n", ctrl->wLength);
361 req->context = hidg;
362 req->complete = hidg_set_report_complete;
363 goto respond;
364 break;
365
366 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
367 | HID_REQ_SET_PROTOCOL):
368 VDBG(cdev, "set_protocol\n");
369 goto stall;
370 break;
371
372 case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
373 | USB_REQ_GET_DESCRIPTOR):
374 switch (value >> 8) {
375 case HID_DT_REPORT:
376 VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
377 length = min_t(unsigned short, length,
378 hidg->report_desc_length);
379 memcpy(req->buf, hidg->report_desc, length);
380 goto respond;
381 break;
382
383 default:
384 VDBG(cdev, "Unknown decriptor request 0x%x\n",
385 value >> 8);
386 goto stall;
387 break;
388 }
389 break;
390
391 default:
392 VDBG(cdev, "Unknown request 0x%x\n",
393 ctrl->bRequest);
394 goto stall;
395 break;
396 }
397
398stall:
399 return -EOPNOTSUPP;
400
401respond:
402 req->zero = 0;
403 req->length = length;
404 status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
405 if (status < 0)
406 ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
407 return status;
408}
409
410static void hidg_disable(struct usb_function *f)
411{
412 struct f_hidg *hidg = func_to_hidg(f);
413
414 usb_ep_disable(hidg->in_ep);
415 hidg->in_ep->driver_data = NULL;
416
417 return;
418}
419
420static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
421{
422 struct usb_composite_dev *cdev = f->config->cdev;
423 struct f_hidg *hidg = func_to_hidg(f);
424 const struct usb_endpoint_descriptor *ep_desc;
425 int status = 0;
426
427 VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);
428
429 if (hidg->in_ep != NULL) {
430 /* restart endpoint */
431 if (hidg->in_ep->driver_data != NULL)
432 usb_ep_disable(hidg->in_ep);
433
434 ep_desc = ep_choose(f->config->cdev->gadget,
435 hidg->hs_in_ep_desc, hidg->fs_in_ep_desc);
436 status = usb_ep_enable(hidg->in_ep, ep_desc);
437 if (status < 0) {
438 ERROR(cdev, "Enable endpoint FAILED!\n");
439 goto fail;
440 }
441 hidg->in_ep->driver_data = hidg;
442 }
443fail:
444 return status;
445}
446
447const struct file_operations f_hidg_fops = {
448 .owner = THIS_MODULE,
449 .open = f_hidg_open,
450 .release = f_hidg_release,
451 .write = f_hidg_write,
452 .read = f_hidg_read,
453 .poll = f_hidg_poll,
454};
455
456static int __init hidg_bind(struct usb_configuration *c, struct usb_function *f)
457{
458 struct usb_ep *ep;
459 struct f_hidg *hidg = func_to_hidg(f);
460 int status;
461 dev_t dev;
462
463 /* allocate instance-specific interface IDs, and patch descriptors */
464 status = usb_interface_id(c, f);
465 if (status < 0)
466 goto fail;
467 hidg_interface_desc.bInterfaceNumber = status;
468
469
470 /* allocate instance-specific endpoints */
471 status = -ENODEV;
472 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
473 if (!ep)
474 goto fail;
475 ep->driver_data = c->cdev; /* claim */
476 hidg->in_ep = ep;
477
478 /* preallocate request and buffer */
479 status = -ENOMEM;
480 hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
481 if (!hidg->req)
482 goto fail;
483
484
485 hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
486 if (!hidg->req->buf)
487 goto fail;
488
489 /* set descriptor dynamic values */
490 hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
491 hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
492 hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
493 hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
494 hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
495 hidg_desc.desc[0].wDescriptorLength =
496 cpu_to_le16(hidg->report_desc_length);
497
498 hidg->set_report_buff = NULL;
499
500 /* copy descriptors */
501 f->descriptors = usb_copy_descriptors(hidg_fs_descriptors);
502 if (!f->descriptors)
503 goto fail;
504
505 hidg->fs_in_ep_desc = usb_find_endpoint(hidg_fs_descriptors,
506 f->descriptors,
507 &hidg_fs_in_ep_desc);
508
509 if (gadget_is_dualspeed(c->cdev->gadget)) {
510 hidg_hs_in_ep_desc.bEndpointAddress =
511 hidg_fs_in_ep_desc.bEndpointAddress;
512 f->hs_descriptors = usb_copy_descriptors(hidg_hs_descriptors);
513 if (!f->hs_descriptors)
514 goto fail;
515 hidg->hs_in_ep_desc = usb_find_endpoint(hidg_hs_descriptors,
516 f->hs_descriptors,
517 &hidg_hs_in_ep_desc);
518 } else {
519 hidg->hs_in_ep_desc = NULL;
520 }
521
522 mutex_init(&hidg->lock);
523 spin_lock_init(&hidg->spinlock);
524 init_waitqueue_head(&hidg->write_queue);
525 init_waitqueue_head(&hidg->read_queue);
526
527 /* create char device */
528 cdev_init(&hidg->cdev, &f_hidg_fops);
529 dev = MKDEV(major, hidg->minor);
530 status = cdev_add(&hidg->cdev, dev, 1);
531 if (status)
532 goto fail;
533
534 device_create(hidg_class, NULL, dev, NULL, "%s%d", "hidg", hidg->minor);
535
536 return 0;
537
538fail:
539 ERROR(f->config->cdev, "hidg_bind FAILED\n");
540 if (hidg->req != NULL) {
541 kfree(hidg->req->buf);
542 if (hidg->in_ep != NULL)
543 usb_ep_free_request(hidg->in_ep, hidg->req);
544 }
545
546 usb_free_descriptors(f->hs_descriptors);
547 usb_free_descriptors(f->descriptors);
548
549 return status;
550}
551
552static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
553{
554 struct f_hidg *hidg = func_to_hidg(f);
555
556 device_destroy(hidg_class, MKDEV(major, hidg->minor));
557 cdev_del(&hidg->cdev);
558
559 /* disable/free request and end point */
560 usb_ep_disable(hidg->in_ep);
561 usb_ep_dequeue(hidg->in_ep, hidg->req);
562 kfree(hidg->req->buf);
563 usb_ep_free_request(hidg->in_ep, hidg->req);
564
565 /* free descriptors copies */
566 usb_free_descriptors(f->hs_descriptors);
567 usb_free_descriptors(f->descriptors);
568
569 kfree(hidg->report_desc);
570 kfree(hidg->set_report_buff);
571 kfree(hidg);
572}
573
574/*-------------------------------------------------------------------------*/
575/* Strings */
576
577#define CT_FUNC_HID_IDX 0
578
579static struct usb_string ct_func_string_defs[] = {
580 [CT_FUNC_HID_IDX].s = "HID Interface",
581 {}, /* end of list */
582};
583
584static struct usb_gadget_strings ct_func_string_table = {
585 .language = 0x0409, /* en-US */
586 .strings = ct_func_string_defs,
587};
588
589static struct usb_gadget_strings *ct_func_strings[] = {
590 &ct_func_string_table,
591 NULL,
592};
593
594/*-------------------------------------------------------------------------*/
595/* usb_configuration */
596
597int __init hidg_bind_config(struct usb_configuration *c,
598 struct hidg_func_descriptor *fdesc, int index)
599{
600 struct f_hidg *hidg;
601 int status;
602
603 if (index >= minors)
604 return -ENOENT;
605
606 /* maybe allocate device-global string IDs, and patch descriptors */
607 if (ct_func_string_defs[CT_FUNC_HID_IDX].id == 0) {
608 status = usb_string_id(c->cdev);
609 if (status < 0)
610 return status;
611 ct_func_string_defs[CT_FUNC_HID_IDX].id = status;
612 hidg_interface_desc.iInterface = status;
613 }
614
615 /* allocate and initialize one new instance */
616 hidg = kzalloc(sizeof *hidg, GFP_KERNEL);
617 if (!hidg)
618 return -ENOMEM;
619
620 hidg->minor = index;
621 hidg->bInterfaceSubClass = fdesc->subclass;
622 hidg->bInterfaceProtocol = fdesc->protocol;
623 hidg->report_length = fdesc->report_length;
624 hidg->report_desc_length = fdesc->report_desc_length;
625 hidg->report_desc = kmemdup(fdesc->report_desc,
626 fdesc->report_desc_length,
627 GFP_KERNEL);
628 if (!hidg->report_desc) {
629 kfree(hidg);
630 return -ENOMEM;
631 }
632
633 hidg->func.name = "hid";
634 hidg->func.strings = ct_func_strings;
635 hidg->func.bind = hidg_bind;
636 hidg->func.unbind = hidg_unbind;
637 hidg->func.set_alt = hidg_set_alt;
638 hidg->func.disable = hidg_disable;
639 hidg->func.setup = hidg_setup;
640
641 status = usb_add_function(c, &hidg->func);
642 if (status)
643 kfree(hidg);
644
645 return status;
646}
647
648int __init ghid_setup(struct usb_gadget *g, int count)
649{
650 int status;
651 dev_t dev;
652
653 hidg_class = class_create(THIS_MODULE, "hidg");
654
655 status = alloc_chrdev_region(&dev, 0, count, "hidg");
656 if (!status) {
657 major = MAJOR(dev);
658 minors = count;
659 }
660
661 return status;
662}
663
664void ghid_cleanup(void)
665{
666 if (major) {
667 unregister_chrdev_region(MKDEV(major, 0), minors);
668 major = minors = 0;
669 }
670
671 class_destroy(hidg_class);
672 hidg_class = NULL;
673}