Staging
v0.5.1
v0.5.1
f_hid.c
/*
* f_hid.c -- USB HID function driver
*
* Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/utsname.h>
#include <linux/module.h>
#include <linux/hid.h>
#include <linux/cdev.h>
#include <linux/mutex.h>
#include <linux/poll.h>
#include <linux/smp_lock.h>
#include <linux/uaccess.h>
#include <linux/wait.h>
#include <linux/usb/g_hid.h>
static int major, minors;
static struct class *hidg_class;
/*-------------------------------------------------------------------------*/
/* HID gadget struct */
struct f_hidg {
/* configuration */
unsigned char bInterfaceSubClass;
unsigned char bInterfaceProtocol;
unsigned short report_desc_length;
char *report_desc;
unsigned short report_length;
/* recv report */
char *set_report_buff;
unsigned short set_report_length;
spinlock_t spinlock;
wait_queue_head_t read_queue;
/* send report */
struct mutex lock;
bool write_pending;
wait_queue_head_t write_queue;
struct usb_request *req;
int minor;
struct cdev cdev;
struct usb_function func;
struct usb_ep *in_ep;
struct usb_endpoint_descriptor *fs_in_ep_desc;
struct usb_endpoint_descriptor *hs_in_ep_desc;
};
static inline struct f_hidg *func_to_hidg(struct usb_function *f)
{
return container_of(f, struct f_hidg, func);
}
/*-------------------------------------------------------------------------*/
/* Static descriptors */
static struct usb_interface_descriptor hidg_interface_desc = {
.bLength = sizeof hidg_interface_desc,
.bDescriptorType = USB_DT_INTERFACE,
/* .bInterfaceNumber = DYNAMIC */
.bAlternateSetting = 0,
.bNumEndpoints = 1,
.bInterfaceClass = USB_CLASS_HID,
/* .bInterfaceSubClass = DYNAMIC */
/* .bInterfaceProtocol = DYNAMIC */
/* .iInterface = DYNAMIC */
};
static struct hid_descriptor hidg_desc = {
.bLength = sizeof hidg_desc,
.bDescriptorType = HID_DT_HID,
.bcdHID = 0x0101,
.bCountryCode = 0x00,
.bNumDescriptors = 0x1,
/*.desc[0].bDescriptorType = DYNAMIC */
/*.desc[0].wDescriptorLenght = DYNAMIC */
};
/* High-Speed Support */
static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
/*.wMaxPacketSize = DYNAMIC */
.bInterval = 4, /* FIXME: Add this field in the
* HID gadget configuration?
* (struct hidg_func_descriptor)
*/
};
static struct usb_descriptor_header *hidg_hs_descriptors[] = {
(struct usb_descriptor_header *)&hidg_interface_desc,
(struct usb_descriptor_header *)&hidg_desc,
(struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
NULL,
};
/* Full-Speed Support */
static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
/*.wMaxPacketSize = DYNAMIC */
.bInterval = 10, /* FIXME: Add this field in the
* HID gadget configuration?
* (struct hidg_func_descriptor)
*/
};
static struct usb_descriptor_header *hidg_fs_descriptors[] = {
(struct usb_descriptor_header *)&hidg_interface_desc,
(struct usb_descriptor_header *)&hidg_desc,
(struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
NULL,
};
/*-------------------------------------------------------------------------*/
/* Char Device */
static ssize_t f_hidg_read(struct file *file, char __user *buffer,
size_t count, loff_t *ptr)
{
struct f_hidg *hidg = (struct f_hidg *)file->private_data;
char *tmp_buff = NULL;
unsigned long flags;
if (!count)
return 0;
if (!access_ok(VERIFY_WRITE, buffer, count))
return -EFAULT;
spin_lock_irqsave(&hidg->spinlock, flags);
#define READ_COND (hidg->set_report_buff != NULL)
while (!READ_COND) {
spin_unlock_irqrestore(&hidg->spinlock, flags);
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
if (wait_event_interruptible(hidg->read_queue, READ_COND))
return -ERESTARTSYS;
spin_lock_irqsave(&hidg->spinlock, flags);
}
count = min_t(unsigned, count, hidg->set_report_length);
tmp_buff = hidg->set_report_buff;
hidg->set_report_buff = NULL;
spin_unlock_irqrestore(&hidg->spinlock, flags);
if (tmp_buff != NULL) {
/* copy to user outside spinlock */
count -= copy_to_user(buffer, tmp_buff, count);
kfree(tmp_buff);
} else
count = -ENOMEM;
return count;
}
static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
{
struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
if (req->status != 0) {
ERROR(hidg->func.config->cdev,
"End Point Request ERROR: %d\n", req->status);
}
hidg->write_pending = 0;
wake_up(&hidg->write_queue);
}
static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
size_t count, loff_t *offp)
{
struct f_hidg *hidg = (struct f_hidg *)file->private_data;
ssize_t status = -ENOMEM;
if (!access_ok(VERIFY_READ, buffer, count))
return -EFAULT;
mutex_lock(&hidg->lock);
#define WRITE_COND (!hidg->write_pending)
/* write queue */
while (!WRITE_COND) {
mutex_unlock(&hidg->lock);
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
if (wait_event_interruptible_exclusive(
hidg->write_queue, WRITE_COND))
return -ERESTARTSYS;
mutex_lock(&hidg->lock);
}
count = min_t(unsigned, count, hidg->report_length);
status = copy_from_user(hidg->req->buf, buffer, count);
if (status != 0) {
ERROR(hidg->func.config->cdev,
"copy_from_user error\n");
mutex_unlock(&hidg->lock);
return -EINVAL;
}
hidg->req->status = 0;
hidg->req->zero = 0;
hidg->req->length = count;
hidg->req->complete = f_hidg_req_complete;
hidg->req->context = hidg;
hidg->write_pending = 1;
status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC);
if (status < 0) {
ERROR(hidg->func.config->cdev,
"usb_ep_queue error on int endpoint %zd\n", status);
hidg->write_pending = 0;
wake_up(&hidg->write_queue);
} else {
status = count;
}
mutex_unlock(&hidg->lock);
return status;
}
static unsigned int f_hidg_poll(struct file *file, poll_table *wait)
{
struct f_hidg *hidg = (struct f_hidg *)file->private_data;
unsigned int ret = 0;
poll_wait(file, &hidg->read_queue, wait);
poll_wait(file, &hidg->write_queue, wait);
if (WRITE_COND)
ret |= POLLOUT | POLLWRNORM;
if (READ_COND)
ret |= POLLIN | POLLRDNORM;
return ret;
}
#undef WRITE_COND
#undef READ_COND
static int f_hidg_release(struct inode *inode, struct file *fd)
{
fd->private_data = NULL;
return 0;
}
static int f_hidg_open(struct inode *inode, struct file *fd)
{
struct f_hidg *hidg =
container_of(inode->i_cdev, struct f_hidg, cdev);
fd->private_data = hidg;
return 0;
}
/*-------------------------------------------------------------------------*/
/* usb_function */
static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
{
struct f_hidg *hidg = (struct f_hidg *)req->context;
if (req->status != 0 || req->buf == NULL || req->actual == 0) {
ERROR(hidg->func.config->cdev, "%s FAILED\n", __func__);
return;
}
spin_lock(&hidg->spinlock);
hidg->set_report_buff = krealloc(hidg->set_report_buff,
req->actual, GFP_ATOMIC);
if (hidg->set_report_buff == NULL) {
spin_unlock(&hidg->spinlock);
return;
}
hidg->set_report_length = req->actual;
memcpy(hidg->set_report_buff, req->buf, req->actual);
spin_unlock(&hidg->spinlock);
wake_up(&hidg->read_queue);
return;
}
static int hidg_setup(struct usb_function *f,
const struct usb_ctrlrequest *ctrl)
{
struct f_hidg *hidg = func_to_hidg(f);
struct usb_composite_dev *cdev = f->config->cdev;
struct usb_request *req = cdev->req;
int status = 0;
__u16 value, length;
value = __le16_to_cpu(ctrl->wValue);
length = __le16_to_cpu(ctrl->wLength);
VDBG(cdev, "hid_setup crtl_request : bRequestType:0x%x bRequest:0x%x "
"Value:0x%x\n", ctrl->bRequestType, ctrl->bRequest, value);
switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
| HID_REQ_GET_REPORT):
VDBG(cdev, "get_report\n");
/* send an empty report */
length = min_t(unsigned, length, hidg->report_length);
memset(req->buf, 0x0, length);
goto respond;
break;
case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
| HID_REQ_GET_PROTOCOL):
VDBG(cdev, "get_protocol\n");
goto stall;
break;
case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
| HID_REQ_SET_REPORT):
VDBG(cdev, "set_report | wLenght=%d\n", ctrl->wLength);
req->context = hidg;
req->complete = hidg_set_report_complete;
goto respond;
break;
case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
| HID_REQ_SET_PROTOCOL):
VDBG(cdev, "set_protocol\n");
goto stall;
break;
case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
| USB_REQ_GET_DESCRIPTOR):
switch (value >> 8) {
case HID_DT_REPORT:
VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
length = min_t(unsigned short, length,
hidg->report_desc_length);
memcpy(req->buf, hidg->report_desc, length);
goto respond;
break;
default:
VDBG(cdev, "Unknown decriptor request 0x%x\n",
value >> 8);
goto stall;
break;
}
break;
default:
VDBG(cdev, "Unknown request 0x%x\n",
ctrl->bRequest);
goto stall;
break;
}
stall:
return -EOPNOTSUPP;
respond:
req->zero = 0;
req->length = length;
status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
if (status < 0)
ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
return status;
}
static void hidg_disable(struct usb_function *f)
{
struct f_hidg *hidg = func_to_hidg(f);
usb_ep_disable(hidg->in_ep);
hidg->in_ep->driver_data = NULL;
return;
}
static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
struct usb_composite_dev *cdev = f->config->cdev;
struct f_hidg *hidg = func_to_hidg(f);
const struct usb_endpoint_descriptor *ep_desc;
int status = 0;
VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);
if (hidg->in_ep != NULL) {
/* restart endpoint */
if (hidg->in_ep->driver_data != NULL)
usb_ep_disable(hidg->in_ep);
ep_desc = ep_choose(f->config->cdev->gadget,
hidg->hs_in_ep_desc, hidg->fs_in_ep_desc);
status = usb_ep_enable(hidg->in_ep, ep_desc);
if (status < 0) {
ERROR(cdev, "Enable endpoint FAILED!\n");
goto fail;
}
hidg->in_ep->driver_data = hidg;
}
fail:
return status;
}
const struct file_operations f_hidg_fops = {
.owner = THIS_MODULE,
.open = f_hidg_open,
.release = f_hidg_release,
.write = f_hidg_write,
.read = f_hidg_read,
.poll = f_hidg_poll,
};
static int __init hidg_bind(struct usb_configuration *c, struct usb_function *f)
{
struct usb_ep *ep;
struct f_hidg *hidg = func_to_hidg(f);
int status;
dev_t dev;
/* allocate instance-specific interface IDs, and patch descriptors */
status = usb_interface_id(c, f);
if (status < 0)
goto fail;
hidg_interface_desc.bInterfaceNumber = status;
/* allocate instance-specific endpoints */
status = -ENODEV;
ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
if (!ep)
goto fail;
ep->driver_data = c->cdev; /* claim */
hidg->in_ep = ep;
/* preallocate request and buffer */
status = -ENOMEM;
hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
if (!hidg->req)
goto fail;
hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
if (!hidg->req->buf)
goto fail;
/* set descriptor dynamic values */
hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
hidg_desc.desc[0].wDescriptorLength =
cpu_to_le16(hidg->report_desc_length);
hidg->set_report_buff = NULL;
/* copy descriptors */
f->descriptors = usb_copy_descriptors(hidg_fs_descriptors);
if (!f->descriptors)
goto fail;
hidg->fs_in_ep_desc = usb_find_endpoint(hidg_fs_descriptors,
f->descriptors,
&hidg_fs_in_ep_desc);
if (gadget_is_dualspeed(c->cdev->gadget)) {
hidg_hs_in_ep_desc.bEndpointAddress =
hidg_fs_in_ep_desc.bEndpointAddress;
f->hs_descriptors = usb_copy_descriptors(hidg_hs_descriptors);
if (!f->hs_descriptors)
goto fail;
hidg->hs_in_ep_desc = usb_find_endpoint(hidg_hs_descriptors,
f->hs_descriptors,
&hidg_hs_in_ep_desc);
} else {
hidg->hs_in_ep_desc = NULL;
}
mutex_init(&hidg->lock);
spin_lock_init(&hidg->spinlock);
init_waitqueue_head(&hidg->write_queue);
init_waitqueue_head(&hidg->read_queue);
/* create char device */
cdev_init(&hidg->cdev, &f_hidg_fops);
dev = MKDEV(major, hidg->minor);
status = cdev_add(&hidg->cdev, dev, 1);
if (status)
goto fail;
device_create(hidg_class, NULL, dev, NULL, "%s%d", "hidg", hidg->minor);
return 0;
fail:
ERROR(f->config->cdev, "hidg_bind FAILED\n");
if (hidg->req != NULL) {
kfree(hidg->req->buf);
if (hidg->in_ep != NULL)
usb_ep_free_request(hidg->in_ep, hidg->req);
}
usb_free_descriptors(f->hs_descriptors);
usb_free_descriptors(f->descriptors);
return status;
}
static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct f_hidg *hidg = func_to_hidg(f);
device_destroy(hidg_class, MKDEV(major, hidg->minor));
cdev_del(&hidg->cdev);
/* disable/free request and end point */
usb_ep_disable(hidg->in_ep);
usb_ep_dequeue(hidg->in_ep, hidg->req);
kfree(hidg->req->buf);
usb_ep_free_request(hidg->in_ep, hidg->req);
/* free descriptors copies */
usb_free_descriptors(f->hs_descriptors);
usb_free_descriptors(f->descriptors);
kfree(hidg->report_desc);
kfree(hidg->set_report_buff);
kfree(hidg);
}
/*-------------------------------------------------------------------------*/
/* Strings */
#define CT_FUNC_HID_IDX 0
static struct usb_string ct_func_string_defs[] = {
[CT_FUNC_HID_IDX].s = "HID Interface",
{}, /* end of list */
};
static struct usb_gadget_strings ct_func_string_table = {
.language = 0x0409, /* en-US */
.strings = ct_func_string_defs,
};
static struct usb_gadget_strings *ct_func_strings[] = {
&ct_func_string_table,
NULL,
};
/*-------------------------------------------------------------------------*/
/* usb_configuration */
int __init hidg_bind_config(struct usb_configuration *c,
struct hidg_func_descriptor *fdesc, int index)
{
struct f_hidg *hidg;
int status;
if (index >= minors)
return -ENOENT;
/* maybe allocate device-global string IDs, and patch descriptors */
if (ct_func_string_defs[CT_FUNC_HID_IDX].id == 0) {
status = usb_string_id(c->cdev);
if (status < 0)
return status;
ct_func_string_defs[CT_FUNC_HID_IDX].id = status;
hidg_interface_desc.iInterface = status;
}
/* allocate and initialize one new instance */
hidg = kzalloc(sizeof *hidg, GFP_KERNEL);
if (!hidg)
return -ENOMEM;
hidg->minor = index;
hidg->bInterfaceSubClass = fdesc->subclass;
hidg->bInterfaceProtocol = fdesc->protocol;
hidg->report_length = fdesc->report_length;
hidg->report_desc_length = fdesc->report_desc_length;
hidg->report_desc = kmemdup(fdesc->report_desc,
fdesc->report_desc_length,
GFP_KERNEL);
if (!hidg->report_desc) {
kfree(hidg);
return -ENOMEM;
}
hidg->func.name = "hid";
hidg->func.strings = ct_func_strings;
hidg->func.bind = hidg_bind;
hidg->func.unbind = hidg_unbind;
hidg->func.set_alt = hidg_set_alt;
hidg->func.disable = hidg_disable;
hidg->func.setup = hidg_setup;
status = usb_add_function(c, &hidg->func);
if (status)
kfree(hidg);
return status;
}
int __init ghid_setup(struct usb_gadget *g, int count)
{
int status;
dev_t dev;
hidg_class = class_create(THIS_MODULE, "hidg");
status = alloc_chrdev_region(&dev, 0, count, "hidg");
if (!status) {
major = MAJOR(dev);
minors = count;
}
return status;
}
void ghid_cleanup(void)
{
if (major) {
unregister_chrdev_region(MKDEV(major, 0), minors);
major = minors = 0;
}
class_destroy(hidg_class);
hidg_class = NULL;
}
