2 * f_hid.c -- USB HID function driver
4 * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
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.
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.
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
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>
33 static int major, minors;
34 static struct class *hidg_class;
36 /*-------------------------------------------------------------------------*/
37 /* HID gadget struct */
41 unsigned char bInterfaceSubClass;
42 unsigned char bInterfaceProtocol;
43 unsigned short report_desc_length;
45 unsigned short report_length;
48 char *set_report_buff;
49 unsigned short set_report_length;
51 wait_queue_head_t read_queue;
56 wait_queue_head_t write_queue;
57 struct usb_request *req;
61 struct usb_function func;
63 struct usb_endpoint_descriptor *fs_in_ep_desc;
64 struct usb_endpoint_descriptor *hs_in_ep_desc;
67 static inline struct f_hidg *func_to_hidg(struct usb_function *f)
69 return container_of(f, struct f_hidg, func);
72 /*-------------------------------------------------------------------------*/
73 /* Static descriptors */
75 static struct usb_interface_descriptor hidg_interface_desc = {
76 .bLength = sizeof hidg_interface_desc,
77 .bDescriptorType = USB_DT_INTERFACE,
78 /* .bInterfaceNumber = DYNAMIC */
79 .bAlternateSetting = 0,
81 .bInterfaceClass = USB_CLASS_HID,
82 /* .bInterfaceSubClass = DYNAMIC */
83 /* .bInterfaceProtocol = DYNAMIC */
84 /* .iInterface = DYNAMIC */
87 static struct hid_descriptor hidg_desc = {
88 .bLength = sizeof hidg_desc,
89 .bDescriptorType = HID_DT_HID,
92 .bNumDescriptors = 0x1,
93 /*.desc[0].bDescriptorType = DYNAMIC */
94 /*.desc[0].wDescriptorLenght = DYNAMIC */
97 /* High-Speed Support */
99 static 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)
111 static 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,
118 /* Full-Speed Support */
120 static 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)
132 static 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,
139 /*-------------------------------------------------------------------------*/
142 static ssize_t f_hidg_read(struct file *file, char __user *buffer,
143 size_t count, loff_t *ptr)
145 struct f_hidg *hidg = file->private_data;
146 char *tmp_buff = NULL;
152 if (!access_ok(VERIFY_WRITE, buffer, count))
155 spin_lock_irqsave(&hidg->spinlock, flags);
157 #define READ_COND (hidg->set_report_buff != NULL)
160 spin_unlock_irqrestore(&hidg->spinlock, flags);
161 if (file->f_flags & O_NONBLOCK)
164 if (wait_event_interruptible(hidg->read_queue, READ_COND))
167 spin_lock_irqsave(&hidg->spinlock, flags);
171 count = min_t(unsigned, count, hidg->set_report_length);
172 tmp_buff = hidg->set_report_buff;
173 hidg->set_report_buff = NULL;
175 spin_unlock_irqrestore(&hidg->spinlock, flags);
177 if (tmp_buff != NULL) {
178 /* copy to user outside spinlock */
179 count -= copy_to_user(buffer, tmp_buff, count);
187 static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
189 struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
191 if (req->status != 0) {
192 ERROR(hidg->func.config->cdev,
193 "End Point Request ERROR: %d\n", req->status);
196 hidg->write_pending = 0;
197 wake_up(&hidg->write_queue);
200 static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
201 size_t count, loff_t *offp)
203 struct f_hidg *hidg = file->private_data;
204 ssize_t status = -ENOMEM;
206 if (!access_ok(VERIFY_READ, buffer, count))
209 mutex_lock(&hidg->lock);
211 #define WRITE_COND (!hidg->write_pending)
214 while (!WRITE_COND) {
215 mutex_unlock(&hidg->lock);
216 if (file->f_flags & O_NONBLOCK)
219 if (wait_event_interruptible_exclusive(
220 hidg->write_queue, WRITE_COND))
223 mutex_lock(&hidg->lock);
226 count = min_t(unsigned, count, hidg->report_length);
227 status = copy_from_user(hidg->req->buf, buffer, count);
230 ERROR(hidg->func.config->cdev,
231 "copy_from_user error\n");
232 mutex_unlock(&hidg->lock);
236 hidg->req->status = 0;
238 hidg->req->length = count;
239 hidg->req->complete = f_hidg_req_complete;
240 hidg->req->context = hidg;
241 hidg->write_pending = 1;
243 status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC);
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);
253 mutex_unlock(&hidg->lock);
258 static unsigned int f_hidg_poll(struct file *file, poll_table *wait)
260 struct f_hidg *hidg = file->private_data;
261 unsigned int ret = 0;
263 poll_wait(file, &hidg->read_queue, wait);
264 poll_wait(file, &hidg->write_queue, wait);
267 ret |= POLLOUT | POLLWRNORM;
270 ret |= POLLIN | POLLRDNORM;
278 static int f_hidg_release(struct inode *inode, struct file *fd)
280 fd->private_data = NULL;
284 static int f_hidg_open(struct inode *inode, struct file *fd)
286 struct f_hidg *hidg =
287 container_of(inode->i_cdev, struct f_hidg, cdev);
289 fd->private_data = hidg;
294 /*-------------------------------------------------------------------------*/
297 static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
299 struct f_hidg *hidg = (struct f_hidg *)req->context;
301 if (req->status != 0 || req->buf == NULL || req->actual == 0) {
302 ERROR(hidg->func.config->cdev, "%s FAILED\n", __func__);
306 spin_lock(&hidg->spinlock);
308 hidg->set_report_buff = krealloc(hidg->set_report_buff,
309 req->actual, GFP_ATOMIC);
311 if (hidg->set_report_buff == NULL) {
312 spin_unlock(&hidg->spinlock);
315 hidg->set_report_length = req->actual;
316 memcpy(hidg->set_report_buff, req->buf, req->actual);
318 spin_unlock(&hidg->spinlock);
320 wake_up(&hidg->read_queue);
325 static int hidg_setup(struct usb_function *f,
326 const struct usb_ctrlrequest *ctrl)
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;
334 value = __le16_to_cpu(ctrl->wValue);
335 length = __le16_to_cpu(ctrl->wLength);
337 VDBG(cdev, "hid_setup crtl_request : bRequestType:0x%x bRequest:0x%x "
338 "Value:0x%x\n", ctrl->bRequestType, ctrl->bRequest, value);
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");
345 /* send an empty report */
346 length = min_t(unsigned, length, hidg->report_length);
347 memset(req->buf, 0x0, length);
352 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
353 | HID_REQ_GET_PROTOCOL):
354 VDBG(cdev, "get_protocol\n");
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);
362 req->complete = hidg_set_report_complete;
366 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
367 | HID_REQ_SET_PROTOCOL):
368 VDBG(cdev, "set_protocol\n");
372 case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
373 | USB_REQ_GET_DESCRIPTOR):
374 switch (value >> 8) {
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);
384 VDBG(cdev, "Unknown decriptor request 0x%x\n",
392 VDBG(cdev, "Unknown request 0x%x\n",
403 req->length = length;
404 status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
406 ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
410 static void hidg_disable(struct usb_function *f)
412 struct f_hidg *hidg = func_to_hidg(f);
414 usb_ep_disable(hidg->in_ep);
415 hidg->in_ep->driver_data = NULL;
420 static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
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;
427 VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);
429 if (hidg->in_ep != NULL) {
430 /* restart endpoint */
431 if (hidg->in_ep->driver_data != NULL)
432 usb_ep_disable(hidg->in_ep);
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);
438 ERROR(cdev, "Enable endpoint FAILED!\n");
441 hidg->in_ep->driver_data = hidg;
447 const struct file_operations f_hidg_fops = {
448 .owner = THIS_MODULE,
450 .release = f_hidg_release,
451 .write = f_hidg_write,
454 .llseek = noop_llseek,
457 static int __init hidg_bind(struct usb_configuration *c, struct usb_function *f)
460 struct f_hidg *hidg = func_to_hidg(f);
464 /* allocate instance-specific interface IDs, and patch descriptors */
465 status = usb_interface_id(c, f);
468 hidg_interface_desc.bInterfaceNumber = status;
471 /* allocate instance-specific endpoints */
473 ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
476 ep->driver_data = c->cdev; /* claim */
479 /* preallocate request and buffer */
481 hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
486 hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
490 /* set descriptor dynamic values */
491 hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
492 hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
493 hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
494 hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
495 hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
496 hidg_desc.desc[0].wDescriptorLength =
497 cpu_to_le16(hidg->report_desc_length);
499 hidg->set_report_buff = NULL;
501 /* copy descriptors */
502 f->descriptors = usb_copy_descriptors(hidg_fs_descriptors);
506 hidg->fs_in_ep_desc = usb_find_endpoint(hidg_fs_descriptors,
508 &hidg_fs_in_ep_desc);
510 if (gadget_is_dualspeed(c->cdev->gadget)) {
511 hidg_hs_in_ep_desc.bEndpointAddress =
512 hidg_fs_in_ep_desc.bEndpointAddress;
513 f->hs_descriptors = usb_copy_descriptors(hidg_hs_descriptors);
514 if (!f->hs_descriptors)
516 hidg->hs_in_ep_desc = usb_find_endpoint(hidg_hs_descriptors,
518 &hidg_hs_in_ep_desc);
520 hidg->hs_in_ep_desc = NULL;
523 mutex_init(&hidg->lock);
524 spin_lock_init(&hidg->spinlock);
525 init_waitqueue_head(&hidg->write_queue);
526 init_waitqueue_head(&hidg->read_queue);
528 /* create char device */
529 cdev_init(&hidg->cdev, &f_hidg_fops);
530 dev = MKDEV(major, hidg->minor);
531 status = cdev_add(&hidg->cdev, dev, 1);
535 device_create(hidg_class, NULL, dev, NULL, "%s%d", "hidg", hidg->minor);
540 ERROR(f->config->cdev, "hidg_bind FAILED\n");
541 if (hidg->req != NULL) {
542 kfree(hidg->req->buf);
543 if (hidg->in_ep != NULL)
544 usb_ep_free_request(hidg->in_ep, hidg->req);
547 usb_free_descriptors(f->hs_descriptors);
548 usb_free_descriptors(f->descriptors);
553 static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
555 struct f_hidg *hidg = func_to_hidg(f);
557 device_destroy(hidg_class, MKDEV(major, hidg->minor));
558 cdev_del(&hidg->cdev);
560 /* disable/free request and end point */
561 usb_ep_disable(hidg->in_ep);
562 usb_ep_dequeue(hidg->in_ep, hidg->req);
563 kfree(hidg->req->buf);
564 usb_ep_free_request(hidg->in_ep, hidg->req);
566 /* free descriptors copies */
567 usb_free_descriptors(f->hs_descriptors);
568 usb_free_descriptors(f->descriptors);
570 kfree(hidg->report_desc);
571 kfree(hidg->set_report_buff);
575 /*-------------------------------------------------------------------------*/
578 #define CT_FUNC_HID_IDX 0
580 static struct usb_string ct_func_string_defs[] = {
581 [CT_FUNC_HID_IDX].s = "HID Interface",
582 {}, /* end of list */
585 static struct usb_gadget_strings ct_func_string_table = {
586 .language = 0x0409, /* en-US */
587 .strings = ct_func_string_defs,
590 static struct usb_gadget_strings *ct_func_strings[] = {
591 &ct_func_string_table,
595 /*-------------------------------------------------------------------------*/
596 /* usb_configuration */
598 int __init hidg_bind_config(struct usb_configuration *c,
599 struct hidg_func_descriptor *fdesc, int index)
607 /* maybe allocate device-global string IDs, and patch descriptors */
608 if (ct_func_string_defs[CT_FUNC_HID_IDX].id == 0) {
609 status = usb_string_id(c->cdev);
612 ct_func_string_defs[CT_FUNC_HID_IDX].id = status;
613 hidg_interface_desc.iInterface = status;
616 /* allocate and initialize one new instance */
617 hidg = kzalloc(sizeof *hidg, GFP_KERNEL);
622 hidg->bInterfaceSubClass = fdesc->subclass;
623 hidg->bInterfaceProtocol = fdesc->protocol;
624 hidg->report_length = fdesc->report_length;
625 hidg->report_desc_length = fdesc->report_desc_length;
626 hidg->report_desc = kmemdup(fdesc->report_desc,
627 fdesc->report_desc_length,
629 if (!hidg->report_desc) {
634 hidg->func.name = "hid";
635 hidg->func.strings = ct_func_strings;
636 hidg->func.bind = hidg_bind;
637 hidg->func.unbind = hidg_unbind;
638 hidg->func.set_alt = hidg_set_alt;
639 hidg->func.disable = hidg_disable;
640 hidg->func.setup = hidg_setup;
642 status = usb_add_function(c, &hidg->func);
649 int __init ghid_setup(struct usb_gadget *g, int count)
654 hidg_class = class_create(THIS_MODULE, "hidg");
656 status = alloc_chrdev_region(&dev, 0, count, "hidg");
665 void ghid_cleanup(void)
668 unregister_chrdev_region(MKDEV(major, 0), minors);
672 class_destroy(hidg_class);