/* * Copyright (c) 2001 Paul Stewart * Copyright (c) 2001 Vojtech Pavlik * * HID char devices, giving access to raw HID device events. * */ /* * 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 * * Should you need to contact me, the author, you can do so either by * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net> */ #include <linux/poll.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/init.h> #include <linux/input.h> #include <linux/usb.h> #include <linux/hid.h> #include <linux/hiddev.h> #include <linux/compat.h> #include "usbhid.h" #ifdef CONFIG_USB_DYNAMIC_MINORS #define HIDDEV_MINOR_BASE 0 #define HIDDEV_MINORS 256 #else #define HIDDEV_MINOR_BASE 96 #define HIDDEV_MINORS 16 #endif #define HIDDEV_BUFFER_SIZE 2048 struct hiddev { int exist; int open; struct mutex existancelock; wait_queue_head_t wait; struct hid_device *hid; struct list_head list; spinlock_t list_lock; }; struct hiddev_list { struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE]; int head; int tail; unsigned flags; struct fasync_struct *fasync; struct hiddev *hiddev; struct list_head node; struct mutex thread_lock; }; /* * Find a report, given the report's type and ID. The ID can be specified * indirectly by REPORT_ID_FIRST (which returns the first report of the given * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the * given type which follows old_id. */ static struct hid_report * hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo) { unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK; unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK; struct hid_report_enum *report_enum; struct hid_report *report; struct list_head *list; if (rinfo->report_type < HID_REPORT_TYPE_MIN || rinfo->report_type > HID_REPORT_TYPE_MAX) return NULL; report_enum = hid->report_enum + (rinfo->report_type - HID_REPORT_TYPE_MIN); switch (flags) { case 0: /* Nothing to do -- report_id is already set correctly */ break; case HID_REPORT_ID_FIRST: if (list_empty(&report_enum->report_list)) return NULL; list = report_enum->report_list.next; report = list_entry(list, struct hid_report, list); rinfo->report_id = report->id; break; case HID_REPORT_ID_NEXT: report = report_enum->report_id_hash[rid]; if (!report) return NULL; list = report->list.next; if (list == &report_enum->report_list) return NULL; report = list_entry(list, struct hid_report, list); rinfo->report_id = report->id; break; default: return NULL; } return report_enum->report_id_hash[rinfo->report_id]; } /* * Perform an exhaustive search of the report table for a usage, given its * type and usage id. */ static struct hid_field * hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref) { int i, j; struct hid_report *report; struct hid_report_enum *report_enum; struct hid_field *field; if (uref->report_type < HID_REPORT_TYPE_MIN || uref->report_type > HID_REPORT_TYPE_MAX) return NULL; report_enum = hid->report_enum + (uref->report_type - HID_REPORT_TYPE_MIN); list_for_each_entry(report, &report_enum->report_list, list) { for (i = 0; i < report->maxfield; i++) { field = report->field[i]; for (j = 0; j < field->maxusage; j++) { if (field->usage[j].hid == uref->usage_code) { uref->report_id = report->id; uref->field_index = i; uref->usage_index = j; return field; } } } } return NULL; } static void hiddev_send_event(struct hid_device *hid, struct hiddev_usage_ref *uref) { struct hiddev *hiddev = hid->hiddev; struct hiddev_list *list; unsigned long flags; spin_lock_irqsave(&hiddev->list_lock, flags); list_for_each_entry(list, &hiddev->list, node) { if (uref->field_index != HID_FIELD_INDEX_NONE || (list->flags & HIDDEV_FLAG_REPORT) != 0) { list->buffer[list->head] = *uref; list->head = (list->head + 1) & (HIDDEV_BUFFER_SIZE - 1); kill_fasync(&list->fasync, SIGIO, POLL_IN); } } spin_unlock_irqrestore(&hiddev->list_lock, flags); wake_up_interruptible(&hiddev->wait); } /* * This is where hid.c calls into hiddev to pass an event that occurred over * the interrupt pipe */ void hiddev_hid_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value) { unsigned type = field->report_type; struct hiddev_usage_ref uref; uref.report_type = (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT : ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT : ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0)); uref.report_id = field->report->id; uref.field_index = field->index; uref.usage_index = (usage - field->usage); uref.usage_code = usage->hid; uref.value = value; hiddev_send_event(hid, &uref); } EXPORT_SYMBOL_GPL(hiddev_hid_event); void hiddev_report_event(struct hid_device *hid, struct hid_report *report) { unsigned type = report->type; struct hiddev_usage_ref uref; memset(&uref, 0, sizeof(uref)); uref.report_type = (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT : ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT : ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0)); uref.report_id = report->id; uref.field_index = HID_FIELD_INDEX_NONE; hiddev_send_event(hid, &uref); } /* * fasync file op */ static int hiddev_fasync(int fd, struct file *file, int on) { struct hiddev_list *list = file->private_data; return fasync_helper(fd, file, on, &list->fasync); } /* * release file op */ static int hiddev_release(struct inode * inode, struct file * file) { struct hiddev_list *list = file->private_data; unsigned long flags; spin_lock_irqsave(&list->hiddev->list_lock, flags); list_del(&list->node); spin_unlock_irqrestore(&list->hiddev->list_lock, flags); mutex_lock(&list->hiddev->existancelock); if (!--list->hiddev->open) { if (list->hiddev->exist) { usbhid_close(list->hiddev->hid); usbhid_put_power(list->hiddev->hid); } else { mutex_unlock(&list->hiddev->existancelock); kfree(list->hiddev); kfree(list); return 0; } } mutex_unlock(&list->hiddev->existancelock); kfree(list); return 0; } /* * open file op */ static int hiddev_open(struct inode *inode, struct file *file) { struct hiddev_list *list; struct usb_interface *intf; struct hid_device *hid; struct hiddev *hiddev; int res; intf = usbhid_find_interface(iminor(inode)); if (!intf) return -ENODEV; hid = usb_get_intfdata(intf); hiddev = hid->hiddev; if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL))) return -ENOMEM; mutex_init(&list->thread_lock); list->hiddev = hiddev; file->private_data = list; /* * no need for locking because the USB major number * is shared which usbcore guards against disconnect */ if (list->hiddev->exist) { if (!list->hiddev->open++) { res = usbhid_open(hiddev->hid); if (res < 0) { res = -EIO; goto bail; } } } else { res = -ENODEV; goto bail; } spin_lock_irq(&list->hiddev->list_lock); list_add_tail(&list->node, &hiddev->list); spin_unlock_irq(&list->hiddev->list_lock); mutex_lock(&hiddev->existancelock); if (!list->hiddev->open++) if (list->hiddev->exist) { struct hid_device *hid = hiddev->hid; res = usbhid_get_power(hid); if (res < 0) { res = -EIO; goto bail_unlock; } usbhid_open(hid); } mutex_unlock(&hiddev->existancelock); return 0; bail_unlock: mutex_unlock(&hiddev->existancelock); bail: file->private_data = NULL; kfree(list); return res; } /* * "write" file op */ static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos) { return -EINVAL; } /* * "read" file op */ static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos) { DEFINE_WAIT(wait); struct hiddev_list *list = file->private_data; int event_size; int retval; event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ? sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event); if (count < event_size) return 0; /* lock against other threads */ retval = mutex_lock_interruptible(&list->thread_lock); if (retval) return -ERESTARTSYS; while (retval == 0) { if (list->head == list->tail) { prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE); while (list->head == list->tail) { if (file->f_flags & O_NONBLOCK) { retval = -EAGAIN; break; } if (signal_pending(current)) { retval = -ERESTARTSYS; break; } if (!list->hiddev->exist) { retval = -EIO; break; } /* let O_NONBLOCK tasks run */ mutex_unlock(&list->thread_lock); schedule(); if (mutex_lock_interruptible(&list->thread_lock)) { finish_wait(&list->hiddev->wait, &wait); return -EINTR; } set_current_state(TASK_INTERRUPTIBLE); } finish_wait(&list->hiddev->wait, &wait); } if (retval) { mutex_unlock(&list->thread_lock); return retval; } while (list->head != list->tail && retval + event_size <= count) { if ((list->flags & HIDDEV_FLAG_UREF) == 0) { if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) { struct hiddev_event event; event.hid = list->buffer[list->tail].usage_code; event.value = list->buffer[list->tail].value; if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) { mutex_unlock(&list->thread_lock); return -EFAULT; } retval += sizeof(struct hiddev_event); } } else { if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE || (list->flags & HIDDEV_FLAG_REPORT) != 0) { if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) { mutex_unlock(&list->thread_lock); return -EFAULT; } retval += sizeof(struct hiddev_usage_ref); } } list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1); } } mutex_unlock(&list->thread_lock); return retval; } /* * "poll" file op * No kernel lock - fine */ static unsigned int hiddev_poll(struct file *file, poll_table *wait) { struct hiddev_list *list = file->private_data; poll_wait(file, &list->hiddev->wait, wait); if (list->head != list->tail) return POLLIN | POLLRDNORM; if (!list->hiddev->exist) return POLLERR | POLLHUP; return 0; } /* * "ioctl" file op */ static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg) { struct hid_device *hid = hiddev->hid; struct hiddev_report_info rinfo; struct hiddev_usage_ref_multi *uref_multi = NULL; struct hiddev_usage_ref *uref; struct hid_report *report; struct hid_field *field; int i; uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL); if (!uref_multi) return -ENOMEM; uref = &uref_multi->uref; if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) { if (copy_from_user(uref_multi, user_arg, sizeof(*uref_multi))) goto fault; } else { if (copy_from_user(uref, user_arg, sizeof(*uref))) goto fault; } switch (cmd) { case HIDIOCGUCODE: rinfo.report_type = uref->report_type; rinfo.report_id = uref->report_id; if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL) goto inval; if (uref->field_index >= report->maxfield) goto inval; field = report->field[uref->field_index]; if (uref->usage_index >= field->maxusage) goto inval; uref->usage_code = field->usage[uref->usage_index].hid; if (copy_to_user(user_arg, uref, sizeof(*uref))) goto fault; goto goodreturn; default: if (cmd != HIDIOCGUSAGE && cmd != HIDIOCGUSAGES && uref->report_type == HID_REPORT_TYPE_INPUT) goto inval; if (uref->report_id == HID_REPORT_ID_UNKNOWN) { field = hiddev_lookup_usage(hid, uref); if (field == NULL) goto inval; } else { rinfo.report_type = uref->report_type; rinfo.report_id = uref->report_id; if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL) goto inval; if (uref->field_index >= report->maxfield) goto inval; field = report->field[uref->field_index]; if (cmd == HIDIOCGCOLLECTIONINDEX) { if (uref->usage_index >= field->maxusage) goto inval; } else if (uref->usage_index >= field->report_count) goto inval; else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) && (uref_multi->num_values > HID_MAX_MULTI_USAGES || uref->usage_index + uref_multi->num_values > field->report_count)) goto inval; } switch (cmd) { case HIDIOCGUSAGE: uref->value = field->value[uref->usage_index]; if (copy_to_user(user_arg, uref, sizeof(*uref))) goto fault; goto goodreturn; case HIDIOCSUSAGE: field->value[uref->usage_index] = uref->value; goto goodreturn; case HIDIOCGCOLLECTIONINDEX: i = field->usage[uref->usage_index].collection_index; kfree(uref_multi); return i; case HIDIOCGUSAGES: for (i = 0; i < uref_multi->num_values; i++) uref_multi->values[i] = field->value[uref->usage_index + i]; if (copy_to_user(user_arg, uref_multi, sizeof(*uref_multi))) goto fault; goto goodreturn; case HIDIOCSUSAGES: for (i = 0; i < uref_multi->num_values; i++) field->value[uref->usage_index + i] = uref_multi->values[i]; goto goodreturn; } goodreturn: kfree(uref_multi); return 0; fault: kfree(uref_multi); return -EFAULT; inval: kfree(uref_multi); return -EINVAL; } } static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg) { struct hid_device *hid = hiddev->hid; struct usb_device *dev = hid_to_usb_dev(hid); int idx, len; char *buf; if (get_user(idx, (int __user *)user_arg)) return -EFAULT; if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL) return -ENOMEM; if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) { kfree(buf); return -EINVAL; } if (copy_to_user(user_arg+sizeof(int), buf, len+1)) { kfree(buf); return -EFAULT; } kfree(buf); return len; } static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct hiddev_list *list = file->private_data; struct hiddev *hiddev = list->hiddev; struct hid_device *hid; struct hiddev_collection_info cinfo; struct hiddev_report_info rinfo; struct hiddev_field_info finfo; struct hiddev_devinfo dinfo; struct hid_report *report; struct hid_field *field; void __user *user_arg = (void __user *)arg; int i, r = -EINVAL; /* Called without BKL by compat methods so no BKL taken */ mutex_lock(&hiddev->existancelock); if (!hiddev->exist) { r = -ENODEV; goto ret_unlock; } hid = hiddev->hid; switch (cmd) { case HIDIOCGVERSION: r = put_user(HID_VERSION, (int __user *)arg) ? -EFAULT : 0; break; case HIDIOCAPPLICATION: if (arg < 0 || arg >= hid->maxapplication) break; for (i = 0; i < hid->maxcollection; i++) if (hid->collection[i].type == HID_COLLECTION_APPLICATION && arg-- == 0) break; if (i < hid->maxcollection) r = hid->collection[i].usage; break; case HIDIOCGDEVINFO: { struct usb_device *dev = hid_to_usb_dev(hid); struct usbhid_device *usbhid = hid->driver_data; dinfo.bustype = BUS_USB; dinfo.busnum = dev->bus->busnum; dinfo.devnum = dev->devnum; dinfo.ifnum = usbhid->ifnum; dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor); dinfo.product = le16_to_cpu(dev->descriptor.idProduct); dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice); dinfo.num_applications = hid->maxapplication; r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ? -EFAULT : 0; break; } case HIDIOCGFLAG: r = put_user(list->flags, (int __user *)arg) ? -EFAULT : 0; break; case HIDIOCSFLAG: { int newflags; if (get_user(newflags, (int __user *)arg)) { r = -EFAULT; break; } if ((newflags & ~HIDDEV_FLAGS) != 0 || ((newflags & HIDDEV_FLAG_REPORT) != 0 && (newflags & HIDDEV_FLAG_UREF) == 0)) break; list->flags = newflags; r = 0; break; } case HIDIOCGSTRING: r = hiddev_ioctl_string(hiddev, cmd, user_arg); break; case HIDIOCINITREPORT: usbhid_init_reports(hid); r = 0; break; case HIDIOCGREPORT: if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) { r = -EFAULT; break; } if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT) break; report = hiddev_lookup_report(hid, &rinfo); if (report == NULL) break; usbhid_submit_report(hid, report, USB_DIR_IN); usbhid_wait_io(hid); r = 0; break; case HIDIOCSREPORT: if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) { r = -EFAULT; break; } if (rinfo.report_type == HID_REPORT_TYPE_INPUT) break; report = hiddev_lookup_report(hid, &rinfo); if (report == NULL) break; usbhid_submit_report(hid, report, USB_DIR_OUT); usbhid_wait_io(hid); r = 0; break; case HIDIOCGREPORTINFO: if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) { r = -EFAULT; break; } report = hiddev_lookup_report(hid, &rinfo); if (report == NULL) break; rinfo.num_fields = report->maxfield; r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ? -EFAULT : 0; break; case HIDIOCGFIELDINFO: if (copy_from_user(&finfo, user_arg, sizeof(finfo))) { r = -EFAULT; break; } rinfo.report_type = finfo.report_type; rinfo.report_id = finfo.report_id; report = hiddev_lookup_report(hid, &rinfo); if (report == NULL) break; if (finfo.field_index >= report->maxfield) break; field = report->field[finfo.field_index]; memset(&finfo, 0, sizeof(finfo)); finfo.report_type = rinfo.report_type; finfo.report_id = rinfo.report_id; finfo.field_index = field->report_count - 1; finfo.maxusage = field->maxusage; finfo.flags = field->flags; finfo.physical = field->physical; finfo.logical = field->logical; finfo.application = field->application; finfo.logical_minimum = field->logical_minimum; finfo.logical_maximum = field->logical_maximum; finfo.physical_minimum = field->physical_minimum; finfo.physical_maximum = field->physical_maximum; finfo.unit_exponent = field->unit_exponent; finfo.unit = field->unit; r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ? -EFAULT : 0; break; case HIDIOCGUCODE: /* fall through */ case HIDIOCGUSAGE: case HIDIOCSUSAGE: case HIDIOCGUSAGES: case HIDIOCSUSAGES: case HIDIOCGCOLLECTIONINDEX: r = hiddev_ioctl_usage(hiddev, cmd, user_arg); break; case HIDIOCGCOLLECTIONINFO: if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) { r = -EFAULT; break; } if (cinfo.index >= hid->maxcollection) break; cinfo.type = hid->collection[cinfo.index].type; cinfo.usage = hid->collection[cinfo.index].usage; cinfo.level = hid->collection[cinfo.index].level; r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ? -EFAULT : 0; break; default: if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ) break; if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) { int len = strlen(hid->name) + 1; if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); r = copy_to_user(user_arg, hid->name, len) ? -EFAULT : len; break; } if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) { int len = strlen(hid->phys) + 1; if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); r = copy_to_user(user_arg, hid->phys, len) ? -EFAULT : len; break; } } ret_unlock: mutex_unlock(&hiddev->existancelock); return r; } #ifdef CONFIG_COMPAT static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); } #endif static const struct file_operations hiddev_fops = { .owner = THIS_MODULE, .read = hiddev_read, .write = hiddev_write, .poll = hiddev_poll, .open = hiddev_open, .release = hiddev_release, .unlocked_ioctl = hiddev_ioctl, .fasync = hiddev_fasync, #ifdef CONFIG_COMPAT .compat_ioctl = hiddev_compat_ioctl, #endif .llseek = noop_llseek, }; static char *hiddev_devnode(struct device *dev, mode_t *mode) { return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); } static struct usb_class_driver hiddev_class = { .name = "hiddev%d", .devnode = hiddev_devnode, .fops = &hiddev_fops, .minor_base = HIDDEV_MINOR_BASE, }; /* * This is where hid.c calls us to connect a hid device to the hiddev driver */ int hiddev_connect(struct hid_device *hid, unsigned int force) { struct hiddev *hiddev; struct usbhid_device *usbhid = hid->driver_data; int retval; if (!force) { unsigned int i; for (i = 0; i < hid->maxcollection; i++) if (hid->collection[i].type == HID_COLLECTION_APPLICATION && !IS_INPUT_APPLICATION(hid->collection[i].usage)) break; if (i == hid->maxcollection) return -1; } if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL))) return -1; init_waitqueue_head(&hiddev->wait); INIT_LIST_HEAD(&hiddev->list); spin_lock_init(&hiddev->list_lock); mutex_init(&hiddev->existancelock); hid->hiddev = hiddev; hiddev->hid = hid; hiddev->exist = 1; retval = usb_register_dev(usbhid->intf, &hiddev_class); if (retval) { hid_err(hid, "Not able to get a minor for this device\n"); hid->hiddev = NULL; kfree(hiddev); return -1; } return 0; } /* * This is where hid.c calls us to disconnect a hiddev device from the * corresponding hid device (usually because the usb device has disconnected) */ static struct usb_class_driver hiddev_class; void hiddev_disconnect(struct hid_device *hid) { struct hiddev *hiddev = hid->hiddev; struct usbhid_device *usbhid = hid->driver_data; mutex_lock(&hiddev->existancelock); hiddev->exist = 0; usb_deregister_dev(usbhid->intf, &hiddev_class); if (hiddev->open) { mutex_unlock(&hiddev->existancelock); usbhid_close(hiddev->hid); wake_up_interruptible(&hiddev->wait); } else { mutex_unlock(&hiddev->existancelock); kfree(hiddev); } }