/** * Generic USB driver for report based interrupt in/out devices * like LD Didactic's USB devices. LD Didactic's USB devices are * HID devices which do not use HID report definitons (they use * raw interrupt in and our reports only for communication). * * This driver uses a ring buffer for time critical reading of * interrupt in reports and provides read and write methods for * raw interrupt reports (similar to the Windows HID driver). * Devices based on the book USB COMPLETE by Jan Axelson may need * such a compatibility to the Windows HID driver. * * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de> * * 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. * * Derived from Lego USB Tower driver * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net> * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net> * * V0.1 (mh) Initial version * V0.11 (mh) Added raw support for HID 1.0 devices (no interrupt out endpoint) * V0.12 (mh) Added kmalloc check for string buffer */ #include <linux/config.h> #include <linux/kernel.h> #include <linux/errno.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/module.h> #include <asm/uaccess.h> #include <linux/input.h> #include <linux/usb.h> #include <linux/poll.h> /* Define these values to match your devices */ #define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */ #define USB_DEVICE_ID_CASSY 0x1000 /* USB Product ID for all CASSY-S modules */ #define USB_DEVICE_ID_POCKETCASSY 0x1010 /* USB Product ID for Pocket-CASSY */ #define USB_DEVICE_ID_MOBILECASSY 0x1020 /* USB Product ID for Mobile-CASSY */ #define USB_DEVICE_ID_JWM 0x1080 /* USB Product ID for Joule and Wattmeter */ #define USB_DEVICE_ID_DMMP 0x1081 /* USB Product ID for Digital Multimeter P (reserved) */ #define USB_DEVICE_ID_UMIP 0x1090 /* USB Product ID for UMI P */ #define USB_DEVICE_ID_VIDEOCOM 0x1200 /* USB Product ID for VideoCom */ #define USB_DEVICE_ID_COM3LAB 0x2000 /* USB Product ID for COM3LAB */ #define USB_DEVICE_ID_TELEPORT 0x2010 /* USB Product ID for Terminal Adapter */ #define USB_DEVICE_ID_NETWORKANALYSER 0x2020 /* USB Product ID for Network Analyser */ #define USB_DEVICE_ID_POWERCONTROL 0x2030 /* USB Product ID for Controlling device for Power Electronics */ #define USB_VENDOR_ID_VERNIER 0x08f7 #define USB_DEVICE_ID_VERNIER_LABPRO 0x0001 #define USB_DEVICE_ID_VERNIER_GOTEMP 0x0002 #define USB_DEVICE_ID_VERNIER_SKIP 0x0003 #define USB_DEVICE_ID_VERNIER_CYCLOPS 0x0004 #ifdef CONFIG_USB_DYNAMIC_MINORS #define USB_LD_MINOR_BASE 0 #else #define USB_LD_MINOR_BASE 176 #endif /* table of devices that work with this driver */ static struct usb_device_id ld_usb_table [] = { { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_CASSY) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_POCKETCASSY) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_MOBILECASSY) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_JWM) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_DMMP) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_UMIP) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_VIDEOCOM) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_COM3LAB) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_TELEPORT) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_NETWORKANALYSER) }, { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_POWERCONTROL) }, { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) }, { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) }, { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) }, { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) }, { } /* Terminating entry */ }; MODULE_DEVICE_TABLE(usb, ld_usb_table); MODULE_VERSION("V0.12"); MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); MODULE_DESCRIPTION("LD USB Driver"); MODULE_LICENSE("GPL"); MODULE_SUPPORTED_DEVICE("LD USB Devices"); #ifdef CONFIG_USB_DEBUG static int debug = 1; #else static int debug = 0; #endif /* Use our own dbg macro */ #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0) /* Module parameters */ module_param(debug, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(debug, "Debug enabled or not"); /* All interrupt in transfers are collected in a ring buffer to * avoid racing conditions and get better performance of the driver. */ static int ring_buffer_size = 128; module_param(ring_buffer_size, int, 0); MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports"); /* The write_buffer can contain more than one interrupt out transfer. */ static int write_buffer_size = 10; module_param(write_buffer_size, int, 0); MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports"); /* As of kernel version 2.6.4 ehci-hcd uses an * "only one interrupt transfer per frame" shortcut * to simplify the scheduling of periodic transfers. * This conflicts with our standard 1ms intervals for in and out URBs. * We use default intervals of 2ms for in and 2ms for out transfers, * which should be fast enough. * Increase the interval to allow more devices that do interrupt transfers, * or set to 1 to use the standard interval from the endpoint descriptors. */ static int min_interrupt_in_interval = 2; module_param(min_interrupt_in_interval, int, 0); MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); static int min_interrupt_out_interval = 2; module_param(min_interrupt_out_interval, int, 0); MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); /* Structure to hold all of our device specific stuff */ struct ld_usb { struct semaphore sem; /* locks this structure */ struct usb_interface* intf; /* save off the usb interface pointer */ int open_count; /* number of times this port has been opened */ char* ring_buffer; unsigned int ring_head; unsigned int ring_tail; wait_queue_head_t read_wait; wait_queue_head_t write_wait; char* interrupt_in_buffer; struct usb_endpoint_descriptor* interrupt_in_endpoint; struct urb* interrupt_in_urb; int interrupt_in_interval; size_t interrupt_in_endpoint_size; int interrupt_in_running; int interrupt_in_done; char* interrupt_out_buffer; struct usb_endpoint_descriptor* interrupt_out_endpoint; struct urb* interrupt_out_urb; int interrupt_out_interval; size_t interrupt_out_endpoint_size; int interrupt_out_busy; }; /* prevent races between open() and disconnect() */ static DECLARE_MUTEX(disconnect_sem); static struct usb_driver ld_usb_driver; /** * ld_usb_abort_transfers * aborts transfers and frees associated data structures */ static void ld_usb_abort_transfers(struct ld_usb *dev) { /* shutdown transfer */ if (dev->interrupt_in_running) { dev->interrupt_in_running = 0; if (dev->intf) usb_kill_urb(dev->interrupt_in_urb); } if (dev->interrupt_out_busy) if (dev->intf) usb_kill_urb(dev->interrupt_out_urb); } /** * ld_usb_delete */ static void ld_usb_delete(struct ld_usb *dev) { ld_usb_abort_transfers(dev); /* free data structures */ usb_free_urb(dev->interrupt_in_urb); usb_free_urb(dev->interrupt_out_urb); kfree(dev->ring_buffer); kfree(dev->interrupt_in_buffer); kfree(dev->interrupt_out_buffer); kfree(dev); } /** * ld_usb_interrupt_in_callback */ static void ld_usb_interrupt_in_callback(struct urb *urb, struct pt_regs *regs) { struct ld_usb *dev = urb->context; size_t *actual_buffer; unsigned int next_ring_head; int retval; if (urb->status) { if (urb->status == -ENOENT || urb->status == -ECONNRESET || urb->status == -ESHUTDOWN) { goto exit; } else { dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n", __FUNCTION__, urb->status); goto resubmit; /* maybe we can recover */ } } if (urb->actual_length > 0) { next_ring_head = (dev->ring_head+1) % ring_buffer_size; if (next_ring_head != dev->ring_tail) { actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ *actual_buffer = urb->actual_length; memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); dev->ring_head = next_ring_head; dbg_info(&dev->intf->dev, "%s: received %d bytes\n", __FUNCTION__, urb->actual_length); } else dev_warn(&dev->intf->dev, "Ring buffer overflow, %d bytes dropped\n", urb->actual_length); } resubmit: /* resubmit if we're still running */ if (dev->interrupt_in_running && dev->intf) { retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); if (retval) dev_err(&dev->intf->dev, "usb_submit_urb failed (%d)\n", retval); } exit: dev->interrupt_in_done = 1; wake_up_interruptible(&dev->read_wait); } /** * ld_usb_interrupt_out_callback */ static void ld_usb_interrupt_out_callback(struct urb *urb, struct pt_regs *regs) { struct ld_usb *dev = urb->context; /* sync/async unlink faults aren't errors */ if (urb->status && !(urb->status == -ENOENT || urb->status == -ECONNRESET || urb->status == -ESHUTDOWN)) dbg_info(&dev->intf->dev, "%s - nonzero write interrupt status received: %d\n", __FUNCTION__, urb->status); dev->interrupt_out_busy = 0; wake_up_interruptible(&dev->write_wait); } /** * ld_usb_open */ static int ld_usb_open(struct inode *inode, struct file *file) { struct ld_usb *dev; int subminor; int retval = 0; struct usb_interface *interface; nonseekable_open(inode, file); subminor = iminor(inode); down(&disconnect_sem); interface = usb_find_interface(&ld_usb_driver, subminor); if (!interface) { err("%s - error, can't find device for minor %d\n", __FUNCTION__, subminor); retval = -ENODEV; goto unlock_disconnect_exit; } dev = usb_get_intfdata(interface); if (!dev) { retval = -ENODEV; goto unlock_disconnect_exit; } /* lock this device */ if (down_interruptible(&dev->sem)) { retval = -ERESTARTSYS; goto unlock_disconnect_exit; } /* allow opening only once */ if (dev->open_count) { retval = -EBUSY; goto unlock_exit; } dev->open_count = 1; /* initialize in direction */ dev->ring_head = 0; dev->ring_tail = 0; usb_fill_int_urb(dev->interrupt_in_urb, interface_to_usbdev(interface), usb_rcvintpipe(interface_to_usbdev(interface), dev->interrupt_in_endpoint->bEndpointAddress), dev->interrupt_in_buffer, dev->interrupt_in_endpoint_size, ld_usb_interrupt_in_callback, dev, dev->interrupt_in_interval); dev->interrupt_in_running = 1; dev->interrupt_in_done = 0; retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); if (retval) { dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); dev->interrupt_in_running = 0; dev->open_count = 0; goto unlock_exit; } /* save device in the file's private structure */ file->private_data = dev; unlock_exit: up(&dev->sem); unlock_disconnect_exit: up(&disconnect_sem); return retval; } /** * ld_usb_release */ static int ld_usb_release(struct inode *inode, struct file *file) { struct ld_usb *dev; int retval = 0; dev = file->private_data; if (dev == NULL) { retval = -ENODEV; goto exit; } if (down_interruptible(&dev->sem)) { retval = -ERESTARTSYS; goto exit; } if (dev->open_count != 1) { retval = -ENODEV; goto unlock_exit; } if (dev->intf == NULL) { /* the device was unplugged before the file was released */ up(&dev->sem); /* unlock here as ld_usb_delete frees dev */ ld_usb_delete(dev); goto exit; } /* wait until write transfer is finished */ if (dev->interrupt_out_busy) wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); ld_usb_abort_transfers(dev); dev->open_count = 0; unlock_exit: up(&dev->sem); exit: return retval; } /** * ld_usb_poll */ static unsigned int ld_usb_poll(struct file *file, poll_table *wait) { struct ld_usb *dev; unsigned int mask = 0; dev = file->private_data; poll_wait(file, &dev->read_wait, wait); poll_wait(file, &dev->write_wait, wait); if (dev->ring_head != dev->ring_tail) mask |= POLLIN | POLLRDNORM; if (!dev->interrupt_out_busy) mask |= POLLOUT | POLLWRNORM; return mask; } /** * ld_usb_read */ static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) { struct ld_usb *dev; size_t *actual_buffer; size_t bytes_to_read; int retval = 0; dev = file->private_data; /* verify that we actually have some data to read */ if (count == 0) goto exit; /* lock this object */ if (down_interruptible(&dev->sem)) { retval = -ERESTARTSYS; goto exit; } /* verify that the device wasn't unplugged */ if (dev->intf == NULL) { retval = -ENODEV; err("No device or device unplugged %d\n", retval); goto unlock_exit; } /* wait for data */ if (dev->ring_head == dev->ring_tail) { if (file->f_flags & O_NONBLOCK) { retval = -EAGAIN; goto unlock_exit; } retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done); if (retval < 0) goto unlock_exit; } /* actual_buffer contains actual_length + interrupt_in_buffer */ actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); bytes_to_read = min(count, *actual_buffer); if (bytes_to_read < *actual_buffer) dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", *actual_buffer-bytes_to_read); /* copy one interrupt_in_buffer from ring_buffer into userspace */ if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { retval = -EFAULT; goto unlock_exit; } dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; retval = bytes_to_read; unlock_exit: /* unlock the device */ up(&dev->sem); exit: return retval; } /** * ld_usb_write */ static ssize_t ld_usb_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) { struct ld_usb *dev; size_t bytes_to_write; int retval = 0; dev = file->private_data; /* verify that we actually have some data to write */ if (count == 0) goto exit; /* lock this object */ if (down_interruptible(&dev->sem)) { retval = -ERESTARTSYS; goto exit; } /* verify that the device wasn't unplugged */ if (dev->intf == NULL) { retval = -ENODEV; err("No device or device unplugged %d\n", retval); goto unlock_exit; } /* wait until previous transfer is finished */ if (dev->interrupt_out_busy) { if (file->f_flags & O_NONBLOCK) { retval = -EAGAIN; goto unlock_exit; } retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); if (retval < 0) { goto unlock_exit; } } /* write the data into interrupt_out_buffer from userspace */ bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); if (bytes_to_write < count) dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write); dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __FUNCTION__, count, bytes_to_write); if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { retval = -EFAULT; goto unlock_exit; } if (dev->interrupt_out_endpoint == NULL) { /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ retval = usb_control_msg(interface_to_usbdev(dev->intf), usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 9, USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 1 << 8, 0, dev->interrupt_out_buffer, bytes_to_write, USB_CTRL_SET_TIMEOUT * HZ); if (retval < 0) err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval); goto unlock_exit; } /* send off the urb */ usb_fill_int_urb(dev->interrupt_out_urb, interface_to_usbdev(dev->intf), usb_sndintpipe(interface_to_usbdev(dev->intf), dev->interrupt_out_endpoint->bEndpointAddress), dev->interrupt_out_buffer, bytes_to_write, ld_usb_interrupt_out_callback, dev, dev->interrupt_out_interval); dev->interrupt_out_busy = 1; wmb(); retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); if (retval) { dev->interrupt_out_busy = 0; err("Couldn't submit interrupt_out_urb %d\n", retval); goto unlock_exit; } retval = bytes_to_write; unlock_exit: /* unlock the device */ up(&dev->sem); exit: return retval; } /* file operations needed when we register this driver */ static struct file_operations ld_usb_fops = { .owner = THIS_MODULE, .read = ld_usb_read, .write = ld_usb_write, .open = ld_usb_open, .release = ld_usb_release, .poll = ld_usb_poll, }; /* * usb class driver info in order to get a minor number from the usb core, * and to have the device registered with devfs and the driver core */ static struct usb_class_driver ld_usb_class = { .name = "ldusb%d", .fops = &ld_usb_fops, .minor_base = USB_LD_MINOR_BASE, }; /** * ld_usb_probe * * Called by the usb core when a new device is connected that it thinks * this driver might be interested in. */ static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct usb_device *udev = interface_to_usbdev(intf); struct ld_usb *dev = NULL; struct usb_host_interface *iface_desc; struct usb_endpoint_descriptor *endpoint; char *buffer; int i; int retval = -ENOMEM; /* allocate memory for our device state and intialize it */ dev = kmalloc(sizeof(*dev), GFP_KERNEL); if (dev == NULL) { dev_err(&intf->dev, "Out of memory\n"); goto exit; } memset(dev, 0x00, sizeof(*dev)); init_MUTEX(&dev->sem); dev->intf = intf; init_waitqueue_head(&dev->read_wait); init_waitqueue_head(&dev->write_wait); /* workaround for early firmware versions on fast computers */ if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_CASSY) || (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_COM3LAB)) && (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { buffer = kmalloc(256, GFP_KERNEL); if (buffer == NULL) { dev_err(&intf->dev, "Couldn't allocate string buffer\n"); goto error; } /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ usb_string(udev, 255, buffer, 256); kfree(buffer); } iface_desc = intf->cur_altsetting; /* set up the endpoint information */ for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { endpoint = &iface_desc->endpoint[i].desc; if (((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN) && ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)) { dev->interrupt_in_endpoint = endpoint; } if (((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT) && ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)) { dev->interrupt_out_endpoint = endpoint; } } if (dev->interrupt_in_endpoint == NULL) { dev_err(&intf->dev, "Interrupt in endpoint not found\n"); goto error; } if (dev->interrupt_out_endpoint == NULL) dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize); dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); if (!dev->ring_buffer) { dev_err(&intf->dev, "Couldn't allocate ring_buffer\n"); goto error; } dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); if (!dev->interrupt_in_buffer) { dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n"); goto error; } dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); if (!dev->interrupt_in_urb) { dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n"); goto error; } dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) : udev->descriptor.bMaxPacketSize0; dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); if (!dev->interrupt_out_buffer) { dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n"); goto error; } dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); if (!dev->interrupt_out_urb) { dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n"); goto error; } dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; if (dev->interrupt_out_endpoint) dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; /* we can register the device now, as it is ready */ usb_set_intfdata(intf, dev); retval = usb_register_dev(intf, &ld_usb_class); if (retval) { /* something prevented us from registering this driver */ dev_err(&intf->dev, "Not able to get a minor for this device.\n"); usb_set_intfdata(intf, NULL); goto error; } /* let the user know what node this device is now attached to */ dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); exit: return retval; error: ld_usb_delete(dev); return retval; } /** * ld_usb_disconnect * * Called by the usb core when the device is removed from the system. */ static void ld_usb_disconnect(struct usb_interface *intf) { struct ld_usb *dev; int minor; down(&disconnect_sem); dev = usb_get_intfdata(intf); usb_set_intfdata(intf, NULL); down(&dev->sem); minor = intf->minor; /* give back our minor */ usb_deregister_dev(intf, &ld_usb_class); /* if the device is not opened, then we clean up right now */ if (!dev->open_count) { up(&dev->sem); ld_usb_delete(dev); } else { dev->intf = NULL; up(&dev->sem); } up(&disconnect_sem); dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", (minor - USB_LD_MINOR_BASE)); } /* usb specific object needed to register this driver with the usb subsystem */ static struct usb_driver ld_usb_driver = { .name = "ldusb", .probe = ld_usb_probe, .disconnect = ld_usb_disconnect, .id_table = ld_usb_table, }; /** * ld_usb_init */ static int __init ld_usb_init(void) { int retval; /* register this driver with the USB subsystem */ retval = usb_register(&ld_usb_driver); if (retval) err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval); return retval; } /** * ld_usb_exit */ static void __exit ld_usb_exit(void) { /* deregister this driver with the USB subsystem */ usb_deregister(&ld_usb_driver); } module_init(ld_usb_init); module_exit(ld_usb_exit);