diff options
Diffstat (limited to 'drivers/staging/frontier/alphatrack.c')
| -rw-r--r-- | drivers/staging/frontier/alphatrack.c | 849 |
1 files changed, 849 insertions, 0 deletions
diff --git a/drivers/staging/frontier/alphatrack.c b/drivers/staging/frontier/alphatrack.c new file mode 100644 index 00000000000..226b2316310 --- /dev/null +++ b/drivers/staging/frontier/alphatrack.c @@ -0,0 +1,849 @@ +/* + * Frontier Designs Alphatrack driver + * + * Copyright (C) 2007 Michael Taht (m@taht.net) + * + * Based on the usbled driver and ldusb drivers by + * + * Copyright (C) 2004 Greg Kroah-Hartman (greg@kroah.com) + * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de> + * + * The ldusb driver was, in turn, derived from Lego USB Tower driver + * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net> + * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net> + * + * 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, version 2. + * + */ + +/** + * This driver uses a ring buffer for time critical reading of + * interrupt in reports and provides read and write methods for + * raw interrupt reports. + */ + +/* + * Note: this currently uses a dumb ringbuffer for reads and writes. + * A more optimal driver would cache and kill off outstanding urbs that are + * now invalid, and ignore ones that already were in the queue but valid + * as we only have 30 commands for the alphatrack. In particular this is + * key for getting lights to flash in time as otherwise many commands + * can be buffered up before the light change makes it to the interface. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/kobject.h> +#include <linux/mutex.h> + +#include <linux/uaccess.h> +#include <linux/input.h> +#include <linux/usb.h> +#include <linux/poll.h> + +#include "alphatrack.h" + +#define VENDOR_ID 0x165b +#define PRODUCT_ID 0xfad1 + +#ifdef CONFIG_USB_DYNAMIC_MINORS +#define USB_ALPHATRACK_MINOR_BASE 0 +#else +/* FIXME 176 - is another driver's minor - apply for that */ +#define USB_ALPHATRACK_MINOR_BASE 176 +#endif + +/* table of devices that work with this driver */ +static const struct usb_device_id usb_alphatrack_table[] = { + {USB_DEVICE(VENDOR_ID, PRODUCT_ID)}, + {} /* Terminating entry */ +}; + +MODULE_DEVICE_TABLE(usb, usb_alphatrack_table); +MODULE_VERSION("0.41"); +MODULE_AUTHOR("Mike Taht <m@taht.net>"); +MODULE_DESCRIPTION("Alphatrack USB Driver"); +MODULE_LICENSE("GPL"); +MODULE_SUPPORTED_DEVICE("Frontier Designs Alphatrack Control Surface"); + +/* These aren't done yet */ + +#define SUPPRESS_EXTRA_ONLINE_EVENTS 0 +#define BUFFERED_WRITES 0 +#define SUPPRESS_EXTRA_OFFLINE_EVENTS 0 +#define COMPRESS_FADER_EVENTS 0 + +#define BUFFERED_READS 1 +#define RING_BUFFER_SIZE 512 +#define WRITE_BUFFER_SIZE 34 +#define ALPHATRACK_USB_TIMEOUT 10 +#define OUTPUT_CMD_SIZE 8 +#define INPUT_CMD_SIZE 12 +#define ALPHATRACK_DEBUG 0 + +static int debug = ALPHATRACK_DEBUG; + +/* Use our own dbg macro */ +#define dbg_info(dev, format, arg...) do \ + { if (debug) dev_info(dev , format , ## arg); } while (0) + +#define alphatrack_ocmd_info(dev, cmd, format, arg...) + +#define alphatrack_icmd_info(dev, cmd, format, arg...) + +/* 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 = RING_BUFFER_SIZE; + +module_param(ring_buffer_size, int, S_IRUGO); +MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size"); + +/* The write_buffer can one day contain more than one interrupt out transfer.*/ + +static int write_buffer_size = WRITE_BUFFER_SIZE; +module_param(write_buffer_size, int, S_IRUGO); +MODULE_PARM_DESC(write_buffer_size, "Write buffer size"); + +/* + * Increase the interval for debugging purposes. + * or set to 1 to use the standard interval from the endpoint descriptors. + */ + +static int min_interrupt_in_interval = ALPHATRACK_USB_TIMEOUT; +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 = ALPHATRACK_USB_TIMEOUT; +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 usb_alphatrack { + struct mutex mtx; /* locks this structure */ + struct usb_interface *intf; /* save off the usb interface pointer */ + int open_count; /* number of times this port has been opened */ + + /* make gcc happy */ + struct alphatrack_icmd (*ring_buffer)[RING_BUFFER_SIZE]; + struct alphatrack_ocmd (*write_buffer)[WRITE_BUFFER_SIZE]; + unsigned int ring_head; + unsigned int ring_tail; + + wait_queue_head_t read_wait; + wait_queue_head_t write_wait; + + unsigned char *interrupt_in_buffer; + unsigned char *oldi_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; + + atomic_t writes_pending; + int event; /* alternate interface to events */ + int fader; /* 10 bits */ + int lights; /* 23 bits */ + unsigned char dump_state; /* 0 if disabled 1 if enabled */ + unsigned char enable; /* 0 if disabled 1 if enabled */ + unsigned char offline; /* if the device is out of range or asleep */ + unsigned char verbose; /* be verbose in error reporting */ + unsigned char last_cmd[OUTPUT_CMD_SIZE]; + unsigned char screen[32]; +}; + +/* prevent races between open() and disconnect() */ +static DEFINE_MUTEX(disconnect_mutex); + +/* forward declaration */ + +static struct usb_driver usb_alphatrack_driver; + +/** + * usb_alphatrack_abort_transfers + * aborts transfers and frees associated data structures + */ +static void usb_alphatrack_abort_transfers(struct usb_alphatrack *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); +} + +/** usb_alphatrack_delete */ +static void usb_alphatrack_delete(struct usb_alphatrack *dev) +{ + usb_alphatrack_abort_transfers(dev); + 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->oldi_buffer); + kfree(dev->write_buffer); + kfree(dev); +} + +/** usb_alphatrack_interrupt_in_callback */ + +static void usb_alphatrack_interrupt_in_callback(struct urb *urb) +{ + struct usb_alphatrack *dev = urb->context; + unsigned int next_ring_head; + int retval = -1; + + 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", __func__, + urb->status); + goto resubmit; /* maybe we can recover */ + } + } + + if (urb->actual_length != INPUT_CMD_SIZE) { + dev_warn(&dev->intf->dev, + "Urb length was %d bytes!! Do something intelligent\n", + urb->actual_length); + } else { + alphatrack_ocmd_info(&dev->intf->dev, + &(*dev->ring_buffer)[dev->ring_tail].cmd, + "%s", "bla"); + if (memcmp + (dev->interrupt_in_buffer, dev->oldi_buffer, + INPUT_CMD_SIZE) == 0) { + goto resubmit; + } + memcpy(dev->oldi_buffer, dev->interrupt_in_buffer, + INPUT_CMD_SIZE); + +#if SUPPRESS_EXTRA_OFFLINE_EVENTS + if (dev->offline == 2 && dev->interrupt_in_buffer[1] == 0xff) + goto resubmit; + if (dev->offline == 1 && dev->interrupt_in_buffer[1] == 0xff) { + dev->offline = 2; + goto resubmit; + } +/* Always pass one offline event up the stack */ + if (dev->offline > 0 && dev->interrupt_in_buffer[1] != 0xff) + dev->offline = 0; + if (dev->offline == 0 && dev->interrupt_in_buffer[1] == 0xff) + dev->offline = 1; +#endif + dbg_info(&dev->intf->dev, "%s: head, tail are %x, %x\n", + __func__, dev->ring_head, dev->ring_tail); + next_ring_head = (dev->ring_head + 1) % ring_buffer_size; + + if (next_ring_head != dev->ring_tail) { + memcpy(&((*dev->ring_buffer)[dev->ring_head]), + dev->interrupt_in_buffer, urb->actual_length); + dev->ring_head = next_ring_head; + retval = 0; + memset(dev->interrupt_in_buffer, 0, urb->actual_length); + } else { + dev_warn(&dev->intf->dev, + "Ring buffer overflow, %d bytes dropped\n", + urb->actual_length); + memset(dev->interrupt_in_buffer, 0, 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); +} + +/** usb_alphatrack_interrupt_out_callback */ +static void usb_alphatrack_interrupt_out_callback(struct urb *urb) +{ + struct usb_alphatrack *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", + __func__, urb->status); + atomic_dec(&dev->writes_pending); + dev->interrupt_out_busy = 0; + wake_up_interruptible(&dev->write_wait); +} + +/** usb_alphatrack_open */ +static int usb_alphatrack_open(struct inode *inode, struct file *file) +{ + struct usb_alphatrack *dev; + int subminor; + int retval = 0; + struct usb_interface *interface; + + nonseekable_open(inode, file); + subminor = iminor(inode); + + mutex_lock(&disconnect_mutex); + + interface = usb_find_interface(&usb_alphatrack_driver, subminor); + + if (!interface) { + pr_err("%s - error, can't find device for minor %d\n", + __func__, subminor); + retval = -ENODEV; + goto unlock_disconnect_exit; + } + + dev = usb_get_intfdata(interface); + + if (!dev) { + retval = -ENODEV; + goto unlock_disconnect_exit; + } + + /* lock this device */ + if (mutex_lock_interruptible(&dev->mtx)) { + 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, + usb_alphatrack_interrupt_in_callback, dev, + dev->interrupt_in_interval); + + dev->interrupt_in_running = 1; + dev->interrupt_in_done = 0; + dev->enable = 1; + dev->offline = 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: + mutex_unlock(&dev->mtx); + +unlock_disconnect_exit: + mutex_unlock(&disconnect_mutex); + + return retval; +} + +/** usb_alphatrack_release */ +static int usb_alphatrack_release(struct inode *inode, struct file *file) +{ + struct usb_alphatrack *dev; + int retval = 0; + + dev = file->private_data; + + if (dev == NULL) { + retval = -ENODEV; + goto exit; + } + + if (mutex_lock_interruptible(&dev->mtx)) { + 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 */ + mutex_unlock(&dev->mtx); + /* unlock here as usb_alphatrack_delete frees dev */ + usb_alphatrack_delete(dev); + retval = -ENODEV; + 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); + usb_alphatrack_abort_transfers(dev); + dev->open_count = 0; + +unlock_exit: + mutex_unlock(&dev->mtx); + +exit: + return retval; +} + +/** usb_alphatrack_poll */ +static unsigned int usb_alphatrack_poll(struct file *file, poll_table *wait) +{ + struct usb_alphatrack *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; +} + +/** usb_alphatrack_read */ +static ssize_t usb_alphatrack_read(struct file *file, char __user *buffer, + size_t count, loff_t *ppos) +{ + struct usb_alphatrack *dev; + int retval = 0; + + int c = 0; + + dev = file->private_data; + + /* verify that we actually have some data to read */ + if (count == 0) + goto exit; + + /* lock this object */ + if (mutex_lock_interruptible(&dev->mtx)) { + retval = -ERESTARTSYS; + goto exit; + } + + /* verify that the device wasn't unplugged */ + if (dev->intf == NULL) { + retval = -ENODEV; + pr_err("%s: No device or device unplugged %d\n", + __func__, retval); + goto unlock_exit; + } + + while (dev->ring_head == dev->ring_tail) { + if (file->f_flags & O_NONBLOCK) { + retval = -EAGAIN; + goto unlock_exit; + } + dev->interrupt_in_done = 0; + retval = + wait_event_interruptible(dev->read_wait, + dev->interrupt_in_done); + if (retval < 0) + goto unlock_exit; + } + + alphatrack_ocmd_info(&dev->intf->dev, + &(*dev->ring_buffer)[dev->ring_tail].cmd, "%s", + ": copying to userspace"); + + c = 0; + while ((c < count) && (dev->ring_tail != dev->ring_head)) { + if (copy_to_user + (&buffer[c], &(*dev->ring_buffer)[dev->ring_tail], + INPUT_CMD_SIZE)) { + retval = -EFAULT; + goto unlock_exit; + } + dev->ring_tail = (dev->ring_tail + 1) % ring_buffer_size; + c += INPUT_CMD_SIZE; + dbg_info(&dev->intf->dev, "%s: head, tail are %x, %x\n", + __func__, dev->ring_head, dev->ring_tail); + } + retval = c; + +unlock_exit: + /* unlock the device */ + mutex_unlock(&dev->mtx); + +exit: + return retval; +} + +/** usb_alphatrack_write */ +static ssize_t usb_alphatrack_write(struct file *file, + const char __user *buffer, size_t count, + loff_t *ppos) +{ + struct usb_alphatrack *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 (mutex_lock_interruptible(&dev->mtx)) { + retval = -ERESTARTSYS; + goto exit; + } + + /* verify that the device wasn't unplugged */ + if (dev->intf == NULL) { + retval = -ENODEV; + pr_err("%s: No device or device unplugged %d\n", + __func__, 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 */ + /* FIXME - if you write more than 12 bytes this breaks */ + 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", + __func__, 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) { + dev_err(&dev->intf->dev, "Endpoint should not be null!\n"); + 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, + usb_alphatrack_interrupt_out_callback, dev, + dev->interrupt_out_interval); + dev->interrupt_out_busy = 1; + atomic_inc(&dev->writes_pending); + wmb(); + + retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); + if (retval) { + dev->interrupt_out_busy = 0; + dev_err(&dev->intf->dev, + "Couldn't submit interrupt_out_urb %d\n", retval); + atomic_dec(&dev->writes_pending); + goto unlock_exit; + } + retval = bytes_to_write; + +unlock_exit: + /* unlock the device */ + mutex_unlock(&dev->mtx); + +exit: + return retval; +} + +/* file operations needed when we register this driver */ +static const struct file_operations usb_alphatrack_fops = { + .owner = THIS_MODULE, + .read = usb_alphatrack_read, + .write = usb_alphatrack_write, + .open = usb_alphatrack_open, + .release = usb_alphatrack_release, + .poll = usb_alphatrack_poll, + .llseek = no_llseek, +}; + +/* + * 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 usb_alphatrack_class = { + .name = "alphatrack%d", + .fops = &usb_alphatrack_fops, + .minor_base = USB_ALPHATRACK_MINOR_BASE, +}; + +/** + * usb_alphatrack_probe + * + * Called by the usb core when a new device is connected that it thinks + * this driver might be interested in. + */ +static int usb_alphatrack_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + struct usb_device *udev = interface_to_usbdev(intf); + struct usb_alphatrack *dev = NULL; + struct usb_host_interface *iface_desc; + struct usb_endpoint_descriptor *endpoint; + int i; + int true_size; + int retval = -ENOMEM; + + /* allocate memory for our device state and initialize it */ + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (dev == NULL) + goto exit; + + mutex_init(&dev->mtx); + dev->intf = intf; + init_waitqueue_head(&dev->read_wait); + init_waitqueue_head(&dev->write_wait); + + 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 (usb_endpoint_is_int_in(endpoint)) + dev->interrupt_in_endpoint = endpoint; + + if (usb_endpoint_is_int_out(endpoint)) + 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); + + if (dev->interrupt_in_endpoint_size != 64) + dev_warn(&intf->dev, "Interrupt in endpoint size is not 64!\n"); + + if (ring_buffer_size == 0) + ring_buffer_size = RING_BUFFER_SIZE; + + true_size = min(ring_buffer_size, RING_BUFFER_SIZE); + + /* + * FIXME - there are more usb_alloc routines for dma correctness. + * Needed? + */ + dev->ring_buffer = kmalloc_array(true_size, + sizeof(struct alphatrack_icmd), + GFP_KERNEL); + if (!dev->ring_buffer) + goto error; + + dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, + GFP_KERNEL); + if (!dev->interrupt_in_buffer) + goto error; + + dev->oldi_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); + if (!dev->oldi_buffer) + 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; + + if (dev->interrupt_out_endpoint_size != 64) + dev_warn(&intf->dev, + "Interrupt out endpoint size is not 64!)\n"); + + if (write_buffer_size == 0) + write_buffer_size = WRITE_BUFFER_SIZE; + true_size = min(write_buffer_size, WRITE_BUFFER_SIZE); + + dev->interrupt_out_buffer = + kmalloc_array(true_size, + dev->interrupt_out_endpoint_size, + GFP_KERNEL); + if (!dev->interrupt_out_buffer) + goto error; + + dev->write_buffer = kmalloc_array(true_size, + sizeof(struct alphatrack_ocmd), + GFP_KERNEL); + if (!dev->write_buffer) + 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); + + atomic_set(&dev->writes_pending, 0); + retval = usb_register_dev(intf, &usb_alphatrack_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, + "Alphatrack Device #%d now attached to major %d minor %d\n", + (intf->minor - USB_ALPHATRACK_MINOR_BASE), USB_MAJOR, + intf->minor); + +exit: + return retval; + +error: + usb_alphatrack_delete(dev); + + return retval; +} + +/** + * usb_alphatrack_disconnect + * + * Called by the usb core when the device is removed from the system. + */ +static void usb_alphatrack_disconnect(struct usb_interface *intf) +{ + struct usb_alphatrack *dev; + int minor; + + mutex_lock(&disconnect_mutex); + + dev = usb_get_intfdata(intf); + usb_set_intfdata(intf, NULL); + + mutex_lock(&dev->mtx); + + minor = intf->minor; + + /* give back our minor */ + usb_deregister_dev(intf, &usb_alphatrack_class); + + /* if the device is not opened, then we clean up right now */ + if (!dev->open_count) { + mutex_unlock(&dev->mtx); + usb_alphatrack_delete(dev); + } else { + atomic_set(&dev->writes_pending, 0); + dev->intf = NULL; + mutex_unlock(&dev->mtx); + } + + mutex_unlock(&disconnect_mutex); + + dev_info(&intf->dev, "Alphatrack Surface #%d now disconnected\n", + (minor - USB_ALPHATRACK_MINOR_BASE)); +} + +/* usb specific object needed to register this driver with the usb subsystem */ +static struct usb_driver usb_alphatrack_driver = { + .name = "alphatrack", + .probe = usb_alphatrack_probe, + .disconnect = usb_alphatrack_disconnect, + .id_table = usb_alphatrack_table, +}; + +module_usb_driver(usb_alphatrack_driver); |