/* * LEGO USB Tower driver * * Copyright (C) 2003 David Glance * 2001-2004 Juergen Stuber * * 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 USB Skeleton driver - 0.5 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com) * * History: * * 2001-10-13 - 0.1 js * - first version * 2001-11-03 - 0.2 js * - simplified buffering, one-shot URBs for writing * 2001-11-10 - 0.3 js * - removed IOCTL (setting power/mode is more complicated, postponed) * 2001-11-28 - 0.4 js * - added vendor commands for mode of operation and power level in open * 2001-12-04 - 0.5 js * - set IR mode by default (by oversight 0.4 set VLL mode) * 2002-01-11 - 0.5? pcchan * - make read buffer reusable and work around bytes_to_write issue between * uhci and legusbtower * 2002-09-23 - 0.52 david (david@csse.uwa.edu.au) * - imported into lejos project * - changed wake_up to wake_up_interruptible * - changed to use lego0 rather than tower0 * - changed dbg() to use __func__ rather than deprecated __func__ * 2003-01-12 - 0.53 david (david@csse.uwa.edu.au) * - changed read and write to write everything or * timeout (from a patch by Chris Riesen and Brett Thaeler driver) * - added ioctl functionality to set timeouts * 2003-07-18 - 0.54 davidgsf (david@csse.uwa.edu.au) * - initial import into LegoUSB project * - merge of existing LegoUSB.c driver * 2003-07-18 - 0.56 davidgsf (david@csse.uwa.edu.au) * - port to 2.6 style driver * 2004-02-29 - 0.6 Juergen Stuber * - fix locking * - unlink read URBs which are no longer needed * - allow increased buffer size, eliminates need for timeout on write * - have read URB running continuously * - added poll * - forbid seeking * - added nonblocking I/O * - changed back __func__ to __func__ * - read and log tower firmware version * - reset tower on probe, avoids failure of first write * 2004-03-09 - 0.7 Juergen Stuber * - timeout read now only after inactivity, shorten default accordingly * 2004-03-11 - 0.8 Juergen Stuber * - log major, minor instead of possibly confusing device filename * - whitespace cleanup * 2004-03-12 - 0.9 Juergen Stuber * - normalize whitespace in debug messages * - take care about endianness in control message responses * 2004-03-13 - 0.91 Juergen Stuber * - make default intervals longer to accommodate current EHCI driver * 2004-03-19 - 0.92 Juergen Stuber * - replaced atomic_t by memory barriers * 2004-04-21 - 0.93 Juergen Stuber * - wait for completion of write urb in release (needed for remotecontrol) * - corrected poll for write direction (missing negation) * 2004-04-22 - 0.94 Juergen Stuber * - make device locking interruptible * 2004-04-30 - 0.95 Juergen Stuber * - check for valid udev on resubmitting and unlinking urbs * 2004-08-03 - 0.96 Juergen Stuber * - move reset into open to clean out spurious data */ #include #include #include #include #include #include #include #include #include #include /* Version Information */ #define DRIVER_VERSION "v0.96" #define DRIVER_AUTHOR "Juergen Stuber " #define DRIVER_DESC "LEGO USB Tower Driver" /* The defaults are chosen to work with the latest versions of leJOS and NQC. */ /* Some legacy software likes to receive packets in one piece. * In this case read_buffer_size should exceed the maximal packet length * (417 for datalog uploads), and packet_timeout should be set. */ static int read_buffer_size = 480; module_param(read_buffer_size, int, 0); MODULE_PARM_DESC(read_buffer_size, "Read buffer size"); /* Some legacy software likes to send packets in one piece. * In this case write_buffer_size should exceed the maximal packet length * (417 for firmware and program downloads). * A problem with long writes is that the following read may time out * if the software is not prepared to wait long enough. */ static int write_buffer_size = 480; module_param(write_buffer_size, int, 0); MODULE_PARM_DESC(write_buffer_size, "Write buffer size"); /* Some legacy software expects reads to contain whole LASM packets. * To achieve this, characters which arrive before a packet timeout * occurs will be returned in a single read operation. * A problem with long reads is that the software may time out * if it is not prepared to wait long enough. * The packet timeout should be greater than the time between the * reception of subsequent characters, which should arrive about * every 5ms for the standard 2400 baud. * Set it to 0 to disable. */ static int packet_timeout = 50; module_param(packet_timeout, int, 0); MODULE_PARM_DESC(packet_timeout, "Packet timeout in ms"); /* Some legacy software expects blocking reads to time out. * Timeout occurs after the specified time of read and write inactivity. * Set it to 0 to disable. */ static int read_timeout = 200; module_param(read_timeout, int, 0); MODULE_PARM_DESC(read_timeout, "Read timeout in ms"); /* 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 8ms for out transfers, * which is fast enough for 2400 baud and allows a small additional load. * Increase the interval to allow more devices that do interrupt transfers, * or set to 0 to use the standard interval from the endpoint descriptors. */ static int interrupt_in_interval = 2; module_param(interrupt_in_interval, int, 0); MODULE_PARM_DESC(interrupt_in_interval, "Interrupt in interval in ms"); static int interrupt_out_interval = 8; module_param(interrupt_out_interval, int, 0); MODULE_PARM_DESC(interrupt_out_interval, "Interrupt out interval in ms"); /* Define these values to match your device */ #define LEGO_USB_TOWER_VENDOR_ID 0x0694 #define LEGO_USB_TOWER_PRODUCT_ID 0x0001 /* Vendor requests */ #define LEGO_USB_TOWER_REQUEST_RESET 0x04 #define LEGO_USB_TOWER_REQUEST_GET_VERSION 0xFD struct tower_reset_reply { __le16 size; /* little-endian */ __u8 err_code; __u8 spare; } __attribute__ ((packed)); struct tower_get_version_reply { __le16 size; /* little-endian */ __u8 err_code; __u8 spare; __u8 major; __u8 minor; __le16 build_no; /* little-endian */ } __attribute__ ((packed)); /* table of devices that work with this driver */ static const struct usb_device_id tower_table[] = { { USB_DEVICE(LEGO_USB_TOWER_VENDOR_ID, LEGO_USB_TOWER_PRODUCT_ID) }, { } /* Terminating entry */ }; MODULE_DEVICE_TABLE (usb, tower_table); static DEFINE_MUTEX(open_disc_mutex); #define LEGO_USB_TOWER_MINOR_BASE 160 /* Structure to hold all of our device specific stuff */ struct lego_usb_tower { struct mutex lock; /* locks this structure */ struct usb_device* udev; /* save off the usb device pointer */ unsigned char minor; /* the starting minor number for this device */ int open_count; /* number of times this port has been opened */ char* read_buffer; size_t read_buffer_length; /* this much came in */ size_t read_packet_length; /* this much will be returned on read */ spinlock_t read_buffer_lock; int packet_timeout_jiffies; unsigned long read_last_arrival; 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; 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; int interrupt_out_busy; }; /* local function prototypes */ static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos); static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos); static inline void tower_delete (struct lego_usb_tower *dev); static int tower_open (struct inode *inode, struct file *file); static int tower_release (struct inode *inode, struct file *file); static unsigned int tower_poll (struct file *file, poll_table *wait); static loff_t tower_llseek (struct file *file, loff_t off, int whence); static void tower_abort_transfers (struct lego_usb_tower *dev); static void tower_check_for_read_packet (struct lego_usb_tower *dev); static void tower_interrupt_in_callback (struct urb *urb); static void tower_interrupt_out_callback (struct urb *urb); static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id); static void tower_disconnect (struct usb_interface *interface); /* file operations needed when we register this driver */ static const struct file_operations tower_fops = { .owner = THIS_MODULE, .read = tower_read, .write = tower_write, .open = tower_open, .release = tower_release, .poll = tower_poll, .llseek = tower_llseek, }; static char *legousbtower_devnode(struct device *dev, umode_t *mode) { return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev)); } /* * usb class driver info in order to get a minor number from the usb core, * and to have the device registered with the driver core */ static struct usb_class_driver tower_class = { .name = "legousbtower%d", .devnode = legousbtower_devnode, .fops = &tower_fops, .minor_base = LEGO_USB_TOWER_MINOR_BASE, }; /* usb specific object needed to register this driver with the usb subsystem */ static struct usb_driver tower_driver = { .name = "legousbtower", .probe = tower_probe, .disconnect = tower_disconnect, .id_table = tower_table, }; /** * lego_usb_tower_debug_data */ static inline void lego_usb_tower_debug_data(struct device *dev, const char *function, int size, const unsigned char *data) { dev_dbg(dev, "%s - length = %d, data = %*ph\n", function, size, size, data); } /** * tower_delete */ static inline void tower_delete (struct lego_usb_tower *dev) { tower_abort_transfers (dev); /* free data structures */ usb_free_urb(dev->interrupt_in_urb); usb_free_urb(dev->interrupt_out_urb); kfree (dev->read_buffer); kfree (dev->interrupt_in_buffer); kfree (dev->interrupt_out_buffer); kfree (dev); } /** * tower_open */ static int tower_open (struct inode *inode, struct file *file) { struct lego_usb_tower *dev = NULL; int subminor; int retval = 0; struct usb_interface *interface; struct tower_reset_reply reset_reply; int result; nonseekable_open(inode, file); subminor = iminor(inode); interface = usb_find_interface (&tower_driver, subminor); if (!interface) { printk(KERN_ERR "%s - error, can't find device for minor %d\n", __func__, subminor); retval = -ENODEV; goto exit; } mutex_lock(&open_disc_mutex); dev = usb_get_intfdata(interface); if (!dev) { mutex_unlock(&open_disc_mutex); retval = -ENODEV; goto exit; } /* lock this device */ if (mutex_lock_interruptible(&dev->lock)) { mutex_unlock(&open_disc_mutex); retval = -ERESTARTSYS; goto exit; } /* allow opening only once */ if (dev->open_count) { mutex_unlock(&open_disc_mutex); retval = -EBUSY; goto unlock_exit; } dev->open_count = 1; mutex_unlock(&open_disc_mutex); /* reset the tower */ result = usb_control_msg (dev->udev, usb_rcvctrlpipe(dev->udev, 0), LEGO_USB_TOWER_REQUEST_RESET, USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE, 0, 0, &reset_reply, sizeof(reset_reply), 1000); if (result < 0) { dev_err(&dev->udev->dev, "LEGO USB Tower reset control request failed\n"); retval = result; goto unlock_exit; } /* initialize in direction */ dev->read_buffer_length = 0; dev->read_packet_length = 0; usb_fill_int_urb (dev->interrupt_in_urb, dev->udev, usb_rcvintpipe(dev->udev, dev->interrupt_in_endpoint->bEndpointAddress), dev->interrupt_in_buffer, usb_endpoint_maxp(dev->interrupt_in_endpoint), tower_interrupt_in_callback, dev, dev->interrupt_in_interval); dev->interrupt_in_running = 1; dev->interrupt_in_done = 0; mb(); retval = usb_submit_urb (dev->interrupt_in_urb, GFP_KERNEL); if (retval) { dev_err(&dev->udev->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: mutex_unlock(&dev->lock); exit: return retval; } /** * tower_release */ static int tower_release (struct inode *inode, struct file *file) { struct lego_usb_tower *dev; int retval = 0; dev = file->private_data; if (dev == NULL) { retval = -ENODEV; goto exit_nolock; } mutex_lock(&open_disc_mutex); if (mutex_lock_interruptible(&dev->lock)) { retval = -ERESTARTSYS; goto exit; } if (dev->open_count != 1) { dev_dbg(&dev->udev->dev, "%s: device not opened exactly once\n", __func__); retval = -ENODEV; goto unlock_exit; } if (dev->udev == NULL) { /* the device was unplugged before the file was released */ /* unlock here as tower_delete frees dev */ mutex_unlock(&dev->lock); tower_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); } tower_abort_transfers (dev); dev->open_count = 0; unlock_exit: mutex_unlock(&dev->lock); exit: mutex_unlock(&open_disc_mutex); exit_nolock: return retval; } /** * tower_abort_transfers * aborts transfers and frees associated data structures */ static void tower_abort_transfers (struct lego_usb_tower *dev) { if (dev == NULL) return; /* shutdown transfer */ if (dev->interrupt_in_running) { dev->interrupt_in_running = 0; mb(); if (dev->udev) usb_kill_urb (dev->interrupt_in_urb); } if (dev->interrupt_out_busy && dev->udev) usb_kill_urb(dev->interrupt_out_urb); } /** * tower_check_for_read_packet * * To get correct semantics for signals and non-blocking I/O * with packetizing we pretend not to see any data in the read buffer * until it has been there unchanged for at least * dev->packet_timeout_jiffies, or until the buffer is full. */ static void tower_check_for_read_packet (struct lego_usb_tower *dev) { spin_lock_irq (&dev->read_buffer_lock); if (!packet_timeout || time_after(jiffies, dev->read_last_arrival + dev->packet_timeout_jiffies) || dev->read_buffer_length == read_buffer_size) { dev->read_packet_length = dev->read_buffer_length; } dev->interrupt_in_done = 0; spin_unlock_irq (&dev->read_buffer_lock); } /** * tower_poll */ static unsigned int tower_poll (struct file *file, poll_table *wait) { struct lego_usb_tower *dev; unsigned int mask = 0; dev = file->private_data; if (!dev->udev) return POLLERR | POLLHUP; poll_wait(file, &dev->read_wait, wait); poll_wait(file, &dev->write_wait, wait); tower_check_for_read_packet(dev); if (dev->read_packet_length > 0) { mask |= POLLIN | POLLRDNORM; } if (!dev->interrupt_out_busy) { mask |= POLLOUT | POLLWRNORM; } return mask; } /** * tower_llseek */ static loff_t tower_llseek (struct file *file, loff_t off, int whence) { return -ESPIPE; /* unseekable */ } /** * tower_read */ static ssize_t tower_read (struct file *file, char __user *buffer, size_t count, loff_t *ppos) { struct lego_usb_tower *dev; size_t bytes_to_read; int i; int retval = 0; unsigned long timeout = 0; dev = file->private_data; /* lock this object */ if (mutex_lock_interruptible(&dev->lock)) { retval = -ERESTARTSYS; goto exit; } /* verify that the device wasn't unplugged */ if (dev->udev == NULL) { retval = -ENODEV; printk(KERN_ERR "legousbtower: No device or device unplugged %d\n", retval); goto unlock_exit; } /* verify that we actually have some data to read */ if (count == 0) { dev_dbg(&dev->udev->dev, "read request of 0 bytes\n"); goto unlock_exit; } if (read_timeout) { timeout = jiffies + read_timeout * HZ / 1000; } /* wait for data */ tower_check_for_read_packet (dev); while (dev->read_packet_length == 0) { if (file->f_flags & O_NONBLOCK) { retval = -EAGAIN; goto unlock_exit; } retval = wait_event_interruptible_timeout(dev->read_wait, dev->interrupt_in_done, dev->packet_timeout_jiffies); if (retval < 0) { goto unlock_exit; } /* reset read timeout during read or write activity */ if (read_timeout && (dev->read_buffer_length || dev->interrupt_out_busy)) { timeout = jiffies + read_timeout * HZ / 1000; } /* check for read timeout */ if (read_timeout && time_after (jiffies, timeout)) { retval = -ETIMEDOUT; goto unlock_exit; } tower_check_for_read_packet (dev); } /* copy the data from read_buffer into userspace */ bytes_to_read = min(count, dev->read_packet_length); if (copy_to_user (buffer, dev->read_buffer, bytes_to_read)) { retval = -EFAULT; goto unlock_exit; } spin_lock_irq (&dev->read_buffer_lock); dev->read_buffer_length -= bytes_to_read; dev->read_packet_length -= bytes_to_read; for (i=0; iread_buffer_length; i++) { dev->read_buffer[i] = dev->read_buffer[i+bytes_to_read]; } spin_unlock_irq (&dev->read_buffer_lock); retval = bytes_to_read; unlock_exit: /* unlock the device */ mutex_unlock(&dev->lock); exit: return retval; } /** * tower_write */ static ssize_t tower_write (struct file *file, const char __user *buffer, size_t count, loff_t *ppos) { struct lego_usb_tower *dev; size_t bytes_to_write; int retval = 0; dev = file->private_data; /* lock this object */ if (mutex_lock_interruptible(&dev->lock)) { retval = -ERESTARTSYS; goto exit; } /* verify that the device wasn't unplugged */ if (dev->udev == NULL) { retval = -ENODEV; printk(KERN_ERR "legousbtower: No device or device unplugged %d\n", retval); goto unlock_exit; } /* verify that we actually have some data to write */ if (count == 0) { dev_dbg(&dev->udev->dev, "write request of 0 bytes\n"); goto unlock_exit; } /* wait until previous transfer is finished */ while (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) { goto unlock_exit; } } /* write the data into interrupt_out_buffer from userspace */ bytes_to_write = min_t(int, count, write_buffer_size); dev_dbg(&dev->udev->dev, "%s: count = %Zd, bytes_to_write = %Zd\n", __func__, count, bytes_to_write); if (copy_from_user (dev->interrupt_out_buffer, buffer, bytes_to_write)) { retval = -EFAULT; goto unlock_exit; } /* send off the urb */ usb_fill_int_urb(dev->interrupt_out_urb, dev->udev, usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress), dev->interrupt_out_buffer, bytes_to_write, tower_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; dev_err(&dev->udev->dev, "Couldn't submit interrupt_out_urb %d\n", retval); goto unlock_exit; } retval = bytes_to_write; unlock_exit: /* unlock the device */ mutex_unlock(&dev->lock); exit: return retval; } /** * tower_interrupt_in_callback */ static void tower_interrupt_in_callback (struct urb *urb) { struct lego_usb_tower *dev = urb->context; int status = urb->status; int retval; lego_usb_tower_debug_data(&dev->udev->dev, __func__, urb->actual_length, urb->transfer_buffer); if (status) { if (status == -ENOENT || status == -ECONNRESET || status == -ESHUTDOWN) { goto exit; } else { dev_dbg(&dev->udev->dev, "%s: nonzero status received: %d\n", __func__, status); goto resubmit; /* maybe we can recover */ } } if (urb->actual_length > 0) { spin_lock (&dev->read_buffer_lock); if (dev->read_buffer_length + urb->actual_length < read_buffer_size) { memcpy (dev->read_buffer + dev->read_buffer_length, dev->interrupt_in_buffer, urb->actual_length); dev->read_buffer_length += urb->actual_length; dev->read_last_arrival = jiffies; dev_dbg(&dev->udev->dev, "%s: received %d bytes\n", __func__, urb->actual_length); } else { printk(KERN_WARNING "%s: read_buffer overflow, %d bytes dropped", __func__, urb->actual_length); } spin_unlock (&dev->read_buffer_lock); } resubmit: /* resubmit if we're still running */ if (dev->interrupt_in_running && dev->udev) { retval = usb_submit_urb (dev->interrupt_in_urb, GFP_ATOMIC); if (retval) dev_err(&dev->udev->dev, "%s: usb_submit_urb failed (%d)\n", __func__, retval); } exit: dev->interrupt_in_done = 1; wake_up_interruptible (&dev->read_wait); } /** * tower_interrupt_out_callback */ static void tower_interrupt_out_callback (struct urb *urb) { struct lego_usb_tower *dev = urb->context; int status = urb->status; lego_usb_tower_debug_data(&dev->udev->dev, __func__, urb->actual_length, urb->transfer_buffer); /* sync/async unlink faults aren't errors */ if (status && !(status == -ENOENT || status == -ECONNRESET || status == -ESHUTDOWN)) { dev_dbg(&dev->udev->dev, "%s: nonzero write bulk status received: %d\n", __func__, status); } dev->interrupt_out_busy = 0; wake_up_interruptible(&dev->write_wait); } /** * tower_probe * * Called by the usb core when a new device is connected that it thinks * this driver might be interested in. */ static int tower_probe (struct usb_interface *interface, const struct usb_device_id *id) { struct device *idev = &interface->dev; struct usb_device *udev = interface_to_usbdev(interface); struct lego_usb_tower *dev = NULL; struct usb_host_interface *iface_desc; struct usb_endpoint_descriptor* endpoint; struct tower_get_version_reply get_version_reply; int i; int retval = -ENOMEM; int result; /* allocate memory for our device state and initialize it */ dev = kmalloc (sizeof(struct lego_usb_tower), GFP_KERNEL); if (dev == NULL) { dev_err(idev, "Out of memory\n"); goto exit; } mutex_init(&dev->lock); dev->udev = udev; dev->open_count = 0; dev->read_buffer = NULL; dev->read_buffer_length = 0; dev->read_packet_length = 0; spin_lock_init (&dev->read_buffer_lock); dev->packet_timeout_jiffies = packet_timeout * HZ / 1000; dev->read_last_arrival = jiffies; init_waitqueue_head (&dev->read_wait); init_waitqueue_head (&dev->write_wait); dev->interrupt_in_buffer = NULL; dev->interrupt_in_endpoint = NULL; dev->interrupt_in_urb = NULL; dev->interrupt_in_running = 0; dev->interrupt_in_done = 0; dev->interrupt_out_buffer = NULL; dev->interrupt_out_endpoint = NULL; dev->interrupt_out_urb = NULL; dev->interrupt_out_busy = 0; iface_desc = interface->cur_altsetting; /* set up the endpoint information */ for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { endpoint = &iface_desc->endpoint[i].desc; if (usb_endpoint_xfer_int(endpoint)) { if (usb_endpoint_dir_in(endpoint)) dev->interrupt_in_endpoint = endpoint; else dev->interrupt_out_endpoint = endpoint; } } if(dev->interrupt_in_endpoint == NULL) { dev_err(idev, "interrupt in endpoint not found\n"); goto error; } if (dev->interrupt_out_endpoint == NULL) { dev_err(idev, "interrupt out endpoint not found\n"); goto error; } dev->read_buffer = kmalloc (read_buffer_size, GFP_KERNEL); if (!dev->read_buffer) { dev_err(idev, "Couldn't allocate read_buffer\n"); goto error; } dev->interrupt_in_buffer = kmalloc (usb_endpoint_maxp(dev->interrupt_in_endpoint), GFP_KERNEL); if (!dev->interrupt_in_buffer) { dev_err(idev, "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(idev, "Couldn't allocate interrupt_in_urb\n"); goto error; } dev->interrupt_out_buffer = kmalloc (write_buffer_size, GFP_KERNEL); if (!dev->interrupt_out_buffer) { dev_err(idev, "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(idev, "Couldn't allocate interrupt_out_urb\n"); goto error; } dev->interrupt_in_interval = interrupt_in_interval ? interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; dev->interrupt_out_interval = interrupt_out_interval ? interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; /* we can register the device now, as it is ready */ usb_set_intfdata (interface, dev); retval = usb_register_dev (interface, &tower_class); if (retval) { /* something prevented us from registering this driver */ dev_err(idev, "Not able to get a minor for this device.\n"); usb_set_intfdata (interface, NULL); goto error; } dev->minor = interface->minor; /* let the user know what node this device is now attached to */ dev_info(&interface->dev, "LEGO USB Tower #%d now attached to major " "%d minor %d\n", (dev->minor - LEGO_USB_TOWER_MINOR_BASE), USB_MAJOR, dev->minor); /* get the firmware version and log it */ result = usb_control_msg (udev, usb_rcvctrlpipe(udev, 0), LEGO_USB_TOWER_REQUEST_GET_VERSION, USB_TYPE_VENDOR | USB_DIR_IN | USB_RECIP_DEVICE, 0, 0, &get_version_reply, sizeof(get_version_reply), 1000); if (result < 0) { dev_err(idev, "LEGO USB Tower get version control request failed\n"); retval = result; goto error; } dev_info(&interface->dev, "LEGO USB Tower firmware version is %d.%d " "build %d\n", get_version_reply.major, get_version_reply.minor, le16_to_cpu(get_version_reply.build_no)); exit: return retval; error: tower_delete(dev); return retval; } /** * tower_disconnect * * Called by the usb core when the device is removed from the system. */ static void tower_disconnect (struct usb_interface *interface) { struct lego_usb_tower *dev; int minor; dev = usb_get_intfdata (interface); mutex_lock(&open_disc_mutex); usb_set_intfdata (interface, NULL); minor = dev->minor; /* give back our minor */ usb_deregister_dev (interface, &tower_class); mutex_lock(&dev->lock); mutex_unlock(&open_disc_mutex); /* if the device is not opened, then we clean up right now */ if (!dev->open_count) { mutex_unlock(&dev->lock); tower_delete (dev); } else { dev->udev = NULL; /* wake up pollers */ wake_up_interruptible_all(&dev->read_wait); wake_up_interruptible_all(&dev->write_wait); mutex_unlock(&dev->lock); } dev_info(&interface->dev, "LEGO USB Tower #%d now disconnected\n", (minor - LEGO_USB_TOWER_MINOR_BASE)); } module_usb_driver(tower_driver); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); #ifdef MODULE_LICENSE MODULE_LICENSE("GPL"); #endif