--- /dev/null
+/*
+ * 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/module.h>
+#include <linux/hid.h>
+#include <linux/idr.h>
+#include <linux/cdev.h>
+#include <linux/mutex.h>
+#include <linux/poll.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/usb/g_hid.h>
+
+#include "u_f.h"
+#include "u_hid.h"
+
+#define HIDG_MINORS 4
+
+static int major, minors;
+static struct class *hidg_class;
+static DEFINE_IDA(hidg_ida);
+static DEFINE_MUTEX(hidg_ida_lock); /* protects access to hidg_ida */
+
+/*-------------------------------------------------------------------------*/
+/* HID gadget struct */
+
+struct f_hidg_req_list {
+ struct usb_request *req;
+ unsigned int pos;
+ struct list_head list;
+};
+
+struct f_hidg {
+ /* configuration */
+ unsigned char bInterfaceSubClass;
+ unsigned char bInterfaceProtocol;
+ unsigned short report_desc_length;
+ char *report_desc;
+ unsigned short report_length;
+
+ /* recv report */
+ struct list_head completed_out_req;
+ spinlock_t spinlock;
+ wait_queue_head_t read_queue;
+ unsigned int qlen;
+
+ /* 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_ep *out_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 = 2,
+ .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_endpoint_descriptor hidg_hs_out_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .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,
+ (struct usb_descriptor_header *)&hidg_hs_out_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_endpoint_descriptor hidg_fs_out_ep_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .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,
+ (struct usb_descriptor_header *)&hidg_fs_out_ep_desc,
+ NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+/* 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,
+};
+
+/*-------------------------------------------------------------------------*/
+/* 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;
+ struct f_hidg_req_list *list;
+ struct usb_request *req;
+ unsigned long flags;
+ int ret;
+
+ if (!count)
+ return 0;
+
+ if (!access_ok(VERIFY_WRITE, buffer, count))
+ return -EFAULT;
+
+ spin_lock_irqsave(&hidg->spinlock, flags);
+
+#define READ_COND (!list_empty(&hidg->completed_out_req))
+
+ /* wait for at least one buffer to complete */
+ 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);
+ }
+
+ /* pick the first one */
+ list = list_first_entry(&hidg->completed_out_req,
+ struct f_hidg_req_list, list);
+ req = list->req;
+ count = min_t(unsigned int, count, req->actual - list->pos);
+ spin_unlock_irqrestore(&hidg->spinlock, flags);
+
+ /* copy to user outside spinlock */
+ count -= copy_to_user(buffer, req->buf + list->pos, count);
+ list->pos += count;
+
+ /*
+ * if this request is completely handled and transfered to
+ * userspace, remove its entry from the list and requeue it
+ * again. Otherwise, we will revisit it again upon the next
+ * call, taking into account its current read position.
+ */
+ if (list->pos == req->actual) {
+ spin_lock_irqsave(&hidg->spinlock, flags);
+ list_del(&list->list);
+ kfree(list);
+ spin_unlock_irqrestore(&hidg->spinlock, flags);
+
+ req->length = hidg->report_length;
+ ret = usb_ep_queue(hidg->out_ep, req, GFP_KERNEL);
+ if (ret < 0)
+ return ret;
+ }
+
+ 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 inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep,
+ unsigned length)
+{
+ return alloc_ep_req(ep, length, length);
+}
+
+static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_hidg *hidg = (struct f_hidg *) req->context;
+ struct f_hidg_req_list *req_list;
+ unsigned long flags;
+
+ req_list = kzalloc(sizeof(*req_list), GFP_ATOMIC);
+ if (!req_list)
+ return;
+
+ req_list->req = req;
+
+ spin_lock_irqsave(&hidg->spinlock, flags);
+ list_add_tail(&req_list->list, &hidg->completed_out_req);
+ spin_unlock_irqrestore(&hidg->spinlock, flags);
+
+ 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,
+ "%s crtl_request : bRequestType:0x%x bRequest:0x%x Value:0x%x\n",
+ __func__, 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 | wLength=%d\n", ctrl->wLength);
+ goto stall;
+ 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:
+ {
+ struct hid_descriptor hidg_desc_copy = hidg_desc;
+
+ VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n");
+ hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT;
+ hidg_desc_copy.desc[0].wDescriptorLength =
+ cpu_to_le16(hidg->report_desc_length);
+
+ length = min_t(unsigned short, length,
+ hidg_desc_copy.bLength);
+ memcpy(req->buf, &hidg_desc_copy, 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 descriptor 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);
+ struct f_hidg_req_list *list, *next;
+
+ usb_ep_disable(hidg->in_ep);
+ hidg->in_ep->driver_data = NULL;
+
+ usb_ep_disable(hidg->out_ep);
+ hidg->out_ep->driver_data = NULL;
+
+ list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
+ list_del(&list->list);
+ kfree(list);
+ }
+}
+
+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 i, 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 IN endpoint FAILED!\n");
+ goto fail;
+ }
+ hidg->in_ep->driver_data = hidg;
+ }
+
+
+ if (hidg->out_ep != NULL) {
+ /* restart endpoint */
+ if (hidg->out_ep->driver_data != NULL)
+ usb_ep_disable(hidg->out_ep);
+
+ status = config_ep_by_speed(f->config->cdev->gadget, f,
+ hidg->out_ep);
+ if (status) {
+ ERROR(cdev, "config_ep_by_speed FAILED!\n");
+ goto fail;
+ }
+ status = usb_ep_enable(hidg->out_ep);
+ if (status < 0) {
+ ERROR(cdev, "Enable IN endpoint FAILED!\n");
+ goto fail;
+ }
+ hidg->out_ep->driver_data = hidg;
+
+ /*
+ * allocate a bunch of read buffers and queue them all at once.
+ */
+ for (i = 0; i < hidg->qlen && status == 0; i++) {
+ struct usb_request *req =
+ hidg_alloc_ep_req(hidg->out_ep,
+ hidg->report_length);
+ if (req) {
+ req->complete = hidg_set_report_complete;
+ req->context = hidg;
+ status = usb_ep_queue(hidg->out_ep, req,
+ GFP_ATOMIC);
+ if (status)
+ ERROR(cdev, "%s queue req --> %d\n",
+ hidg->out_ep->name, status);
+ } else {
+ usb_ep_disable(hidg->out_ep);
+ hidg->out_ep->driver_data = NULL;
+ status = -ENOMEM;
+ goto fail;
+ }
+ }
+ }
+
+fail:
+ return status;
+}
+
+static 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 hidg_bind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct usb_ep *ep;
+ struct f_hidg *hidg = func_to_hidg(f);
+ struct usb_string *us;
+ struct device *device;
+ int status;
+ dev_t dev;
+
+ /* maybe allocate device-global string IDs, and patch descriptors */
+ us = usb_gstrings_attach(c->cdev, ct_func_strings,
+ ARRAY_SIZE(ct_func_string_defs));
+ if (IS_ERR(us))
+ return PTR_ERR(us);
+ hidg_interface_desc.iInterface = us[CT_FUNC_HID_IDX].id;
+
+ /* 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;
+
+ ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
+ if (!ep)
+ goto fail;
+ ep->driver_data = c->cdev; /* claim */
+ hidg->out_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_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+ hidg_fs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+ /*
+ * We can use hidg_desc struct here but we should not relay
+ * that its content won't change after returning from this function.
+ */
+ hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
+ hidg_desc.desc[0].wDescriptorLength =
+ cpu_to_le16(hidg->report_desc_length);
+
+ 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);
+ INIT_LIST_HEAD(&hidg->completed_out_req);
+
+ /* 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_free_descs;
+
+ device = device_create(hidg_class, NULL, dev, NULL,
+ "%s%d", "hidg", hidg->minor);
+ if (IS_ERR(device)) {
+ status = PTR_ERR(device);
+ goto del;
+ }
+
+ return 0;
+del:
+ cdev_del(&hidg->cdev);
+fail_free_descs:
+ usb_free_all_descriptors(f);
+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);
+ }
+
+ return status;
+}
+
+static inline int hidg_get_minor(void)
+{
+ int ret;
+
+ ret = ida_simple_get(&hidg_ida, 0, 0, GFP_KERNEL);
+
+ return ret;
+}
+
+static inline struct f_hid_opts *to_f_hid_opts(struct config_item *item)
+{
+ return container_of(to_config_group(item), struct f_hid_opts,
+ func_inst.group);
+}
+
+CONFIGFS_ATTR_STRUCT(f_hid_opts);
+CONFIGFS_ATTR_OPS(f_hid_opts);
+
+static void hid_attr_release(struct config_item *item)
+{
+ struct f_hid_opts *opts = to_f_hid_opts(item);
+
+ usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations hidg_item_ops = {
+ .release = hid_attr_release,
+ .show_attribute = f_hid_opts_attr_show,
+ .store_attribute = f_hid_opts_attr_store,
+};
+
+#define F_HID_OPT(name, prec, limit) \
+static ssize_t f_hid_opts_##name##_show(struct f_hid_opts *opts, char *page)\
+{ \
+ int result; \
+ \
+ mutex_lock(&opts->lock); \
+ result = sprintf(page, "%d\n", opts->name); \
+ mutex_unlock(&opts->lock); \
+ \
+ return result; \
+} \
+ \
+static ssize_t f_hid_opts_##name##_store(struct f_hid_opts *opts, \
+ const char *page, size_t len) \
+{ \
+ int ret; \
+ u##prec num; \
+ \
+ mutex_lock(&opts->lock); \
+ if (opts->refcnt) { \
+ ret = -EBUSY; \
+ goto end; \
+ } \
+ \
+ ret = kstrtou##prec(page, 0, &num); \
+ if (ret) \
+ goto end; \
+ \
+ if (num > limit) { \
+ ret = -EINVAL; \
+ goto end; \
+ } \
+ opts->name = num; \
+ ret = len; \
+ \
+end: \
+ mutex_unlock(&opts->lock); \
+ return ret; \
+} \
+ \
+static struct f_hid_opts_attribute f_hid_opts_##name = \
+ __CONFIGFS_ATTR(name, S_IRUGO | S_IWUSR, f_hid_opts_##name##_show,\
+ f_hid_opts_##name##_store)
+
+F_HID_OPT(subclass, 8, 255);
+F_HID_OPT(protocol, 8, 255);
+F_HID_OPT(report_length, 16, 65535);
+
+static ssize_t f_hid_opts_report_desc_show(struct f_hid_opts *opts, char *page)
+{
+ int result;
+
+ mutex_lock(&opts->lock);
+ result = opts->report_desc_length;
+ memcpy(page, opts->report_desc, opts->report_desc_length);
+ mutex_unlock(&opts->lock);
+
+ return result;
+}
+
+static ssize_t f_hid_opts_report_desc_store(struct f_hid_opts *opts,
+ const char *page, size_t len)
+{
+ int ret = -EBUSY;
+ char *d;
+
+ mutex_lock(&opts->lock);
+
+ if (opts->refcnt)
+ goto end;
+ if (len > PAGE_SIZE) {
+ ret = -ENOSPC;
+ goto end;
+ }
+ d = kmemdup(page, len, GFP_KERNEL);
+ if (!d) {
+ ret = -ENOMEM;
+ goto end;
+ }
+ kfree(opts->report_desc);
+ opts->report_desc = d;
+ opts->report_desc_length = len;
+ opts->report_desc_alloc = true;
+ ret = len;
+end:
+ mutex_unlock(&opts->lock);
+ return ret;
+}
+
+static struct f_hid_opts_attribute f_hid_opts_report_desc =
+ __CONFIGFS_ATTR(report_desc, S_IRUGO | S_IWUSR,
+ f_hid_opts_report_desc_show,
+ f_hid_opts_report_desc_store);
+
+static struct configfs_attribute *hid_attrs[] = {
+ &f_hid_opts_subclass.attr,
+ &f_hid_opts_protocol.attr,
+ &f_hid_opts_report_length.attr,
+ &f_hid_opts_report_desc.attr,
+ NULL,
+};
+
+static struct config_item_type hid_func_type = {
+ .ct_item_ops = &hidg_item_ops,
+ .ct_attrs = hid_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+static inline void hidg_put_minor(int minor)
+{
+ ida_simple_remove(&hidg_ida, minor);
+}
+
+static void hidg_free_inst(struct usb_function_instance *f)
+{
+ struct f_hid_opts *opts;
+
+ opts = container_of(f, struct f_hid_opts, func_inst);
+
+ mutex_lock(&hidg_ida_lock);
+
+ hidg_put_minor(opts->minor);
+ if (idr_is_empty(&hidg_ida.idr))
+ ghid_cleanup();
+
+ mutex_unlock(&hidg_ida_lock);
+
+ if (opts->report_desc_alloc)
+ kfree(opts->report_desc);
+
+ kfree(opts);
+}
+
+static struct usb_function_instance *hidg_alloc_inst(void)
+{
+ struct f_hid_opts *opts;
+ struct usb_function_instance *ret;
+ int status = 0;
+
+ opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+ if (!opts)
+ return ERR_PTR(-ENOMEM);
+ mutex_init(&opts->lock);
+ opts->func_inst.free_func_inst = hidg_free_inst;
+ ret = &opts->func_inst;
+
+ mutex_lock(&hidg_ida_lock);
+
+ if (idr_is_empty(&hidg_ida.idr)) {
+ status = ghid_setup(NULL, HIDG_MINORS);
+ if (status) {
+ ret = ERR_PTR(status);
+ kfree(opts);
+ goto unlock;
+ }
+ }
+
+ opts->minor = hidg_get_minor();
+ if (opts->minor < 0) {
+ ret = ERR_PTR(opts->minor);
+ kfree(opts);
+ if (idr_is_empty(&hidg_ida.idr))
+ ghid_cleanup();
+ goto unlock;
+ }
+ config_group_init_type_name(&opts->func_inst.group, "", &hid_func_type);
+
+unlock:
+ mutex_unlock(&hidg_ida_lock);
+ return ret;
+}
+
+static void hidg_free(struct usb_function *f)
+{
+ struct f_hidg *hidg;
+ struct f_hid_opts *opts;
+
+ hidg = func_to_hidg(f);
+ opts = container_of(f->fi, struct f_hid_opts, func_inst);
+ kfree(hidg->report_desc);
+ kfree(hidg);
+ mutex_lock(&opts->lock);
+ --opts->refcnt;
+ mutex_unlock(&opts->lock);
+}
+
+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);
+ kfree(hidg->req->buf);
+ usb_ep_free_request(hidg->in_ep, hidg->req);
+
+ usb_free_all_descriptors(f);
+}
+
+static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
+{
+ struct f_hidg *hidg;
+ struct f_hid_opts *opts;
+
+ /* allocate and initialize one new instance */
+ hidg = kzalloc(sizeof(*hidg), GFP_KERNEL);
+ if (!hidg)
+ return ERR_PTR(-ENOMEM);
+
+ opts = container_of(fi, struct f_hid_opts, func_inst);
+
+ mutex_lock(&opts->lock);
+ ++opts->refcnt;
+
+ hidg->minor = opts->minor;
+ hidg->bInterfaceSubClass = opts->subclass;
+ hidg->bInterfaceProtocol = opts->protocol;
+ hidg->report_length = opts->report_length;
+ hidg->report_desc_length = opts->report_desc_length;
+ if (opts->report_desc) {
+ hidg->report_desc = kmemdup(opts->report_desc,
+ opts->report_desc_length,
+ GFP_KERNEL);
+ if (!hidg->report_desc) {
+ kfree(hidg);
+ mutex_unlock(&opts->lock);
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+
+ mutex_unlock(&opts->lock);
+
+ hidg->func.name = "hid";
+ 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;
+ hidg->func.free_func = hidg_free;
+
+ /* this could me made configurable at some point */
+ hidg->qlen = 4;
+
+ return &hidg->func;
+}
+
+DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Fabien Chouteau");
+
+int ghid_setup(struct usb_gadget *g, int count)
+{
+ int status;
+ dev_t dev;
+
+ hidg_class = class_create(THIS_MODULE, "hidg");
+ if (IS_ERR(hidg_class)) {
+ status = PTR_ERR(hidg_class);
+ hidg_class = NULL;
+ return status;
+ }
+
+ status = alloc_chrdev_region(&dev, 0, count, "hidg");
+ if (status) {
+ class_destroy(hidg_class);
+ hidg_class = NULL;
+ return status;
+ }
+
+ major = MAJOR(dev);
+ minors = count;
+
+ return 0;
+}
+
+void ghid_cleanup(void)
+{
+ if (major) {
+ unregister_chrdev_region(MKDEV(major, 0), minors);
+ major = minors = 0;
+ }
+
+ class_destroy(hidg_class);
+ hidg_class = NULL;
+}
Code Review / kvmfornfv.git / blobdiff