| /* |
| * 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. |
| */ |
| |
| #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/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; |
| }; |
| |
| 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 = 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 = 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 = 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); |
| } |
| |
| 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_HID: |
| VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n"); |
| length = min_t(unsigned short, length, |
| hidg_desc.bLength); |
| memcpy(req->buf, &hidg_desc, length); |
| goto respond; |
| break; |
| 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; |
| } |
| |
| 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); |
| 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); |
| |
| status = config_ep_by_speed(f->config->cdev->gadget, f, |
| hidg->in_ep); |
| if (status) { |
| ERROR(cdev, "config_ep_by_speed FAILED!\n"); |
| goto fail; |
| } |
| status = usb_ep_enable(hidg->in_ep); |
| 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, |
| .llseek = noop_llseek, |
| }; |
| |
| 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; |
| |
| hidg_hs_in_ep_desc.bEndpointAddress = |
| hidg_fs_in_ep_desc.bEndpointAddress; |
| hidg_hs_out_ep_desc.bEndpointAddress = |
| hidg_fs_out_ep_desc.bEndpointAddress; |
| |
| status = usb_assign_descriptors(f, hidg_fs_descriptors, |
| hidg_hs_descriptors, NULL); |
| if (status) |
| goto fail; |
| |
| 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_all_descriptors(f); |
| 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); |
| |
| usb_free_all_descriptors(f); |
| |
| 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; |
| } |