/*
* LEGO USB Tower driver
*
* Copyright (C) 2003 David Glance <davidgsf@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; 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 <starblue@users.sourceforge.net>
* - 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 <starblue@users.sourceforge.net>
* - timeout read now only after inactivity, shorten default accordingly
* 2004-03-11 - 0.8 Juergen Stuber <starblue@users.sourceforge.net>
* - log major, minor instead of possibly confusing device filename
* - whitespace cleanup
* 2004-03-12 - 0.9 Juergen Stuber <starblue@users.sourceforge.net>
* - normalize whitespace in debug messages
* - take care about endianness in control message responses
* 2004-03-13 - 0.91 Juergen Stuber <starblue@users.sourceforge.net>
* - make default intervals longer to accommodate current EHCI driver
* 2004-03-19 - 0.92 Juergen Stuber <starblue@users.sourceforge.net>
* - replaced atomic_t by memory barriers
* 2004-04-21 - 0.93 Juergen Stuber <starblue@users.sourceforge.net>
* - 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 <starblue@users.sourceforge.net>
* - make device locking interruptible
* 2004-04-30 - 0.95 Juergen Stuber <starblue@users.sourceforge.net>
* - check for valid udev on resubmitting and unlinking urbs
* 2004-08-03 - 0.96 Juergen Stuber <starblue@users.sourceforge.net>
* - move reset into open to clean out spurious data
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/completion.h>
#include <linux/mutex.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include <linux/poll.h>
#ifdef CONFIG_USB_DEBUG
static int debug = 4;
#else
static int debug = 0;
#endif
/* Use our own dbg macro */
#undef dbg
#define dbg(lvl, format, arg...) \
do { \
if (debug >= lvl) \
printk(KERN_DEBUG "%s: " format "\n", __FILE__, ##arg); \
} while (0)
/* Version Information */
#define DRIVER_VERSION "v0.96"
#define DRIVER_AUTHOR "Juergen Stuber <starblue@sourceforge.net>"
#define DRIVER_DESC "LEGO USB Tower Driver"
/* Module parameters */
module_param(debug, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");
/* 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, mode_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 (int level, const char *function, int size, const unsigned char *data)
{
int i;
if (debug < level)
return;
printk (KERN_DEBUG "%s: %s - length = %d, data = ", __FILE__, function, size);
for (i = 0; i < size; ++i) {
printk ("%.2x ", data[i]);
}
printk ("\n");
}
/**
* tower_delete
*/
static inline void tower_delete (struct lego_usb_tower *dev)
{
dbg(2, "%s: enter", __func__);
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);
dbg(2, "%s: leave", __func__);
}
/**
* 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;
dbg(2, "%s: enter", __func__);
nonseekable_open(inode, file);
subminor = iminor(inode);
interface = usb_find_interface (&tower_driver, subminor);
if (!interface) {
err ("%s - error, can't find device for minor %d",
__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) {
err("LEGO USB Tower reset control request failed");
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,
le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
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) {
err("Couldn't submit interrupt_in_urb %d", 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:
dbg(2, "%s: leave, return value %d ", __func__, retval);
return retval;
}
/**
* tower_release
*/
static int tower_release (struct inode *inode, struct file *file)
{
struct lego_usb_tower *dev;
int retval = 0;
dbg(2, "%s: enter", __func__);
dev = (struct lego_usb_tower *)file->private_data;
if (dev == NULL) {
dbg(1, "%s: object is NULL", __func__);
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) {
dbg(1, "%s: device not opened exactly once", __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:
dbg(2, "%s: leave, return value %d", __func__, retval);
return retval;
}
/**
* tower_abort_transfers
* aborts transfers and frees associated data structures
*/
static void tower_abort_transfers (struct lego_usb_tower *dev)
{
dbg(2, "%s: enter", __func__);
if (dev == NULL) {
dbg(1, "%s: dev is null", __func__);
goto exit;
}
/* 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);
exit:
dbg(2, "%s: leave", __func__);
}
/**
* 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;
dbg(2, "%s: enter", __func__);
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;
}
dbg(2, "%s: leave, mask = %d", __func__, mask);
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;
dbg(2, "%s: enter, count = %Zd", __func__, count);
dev = (struct lego_usb_tower *)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;
err("No device or device unplugged %d", retval);
goto unlock_exit;
}
/* verify that we actually have some data to read */
if (count == 0) {
dbg(1, "%s: read request of 0 bytes", __func__);
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; i<dev->read_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:
dbg(2, "%s: leave, return value %d", __func__, retval);
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;
dbg(2, "%s: enter, count = %Zd", __func__, count);
dev = (struct lego_usb_tower *)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;
err("No device or device unplugged %d", retval);
goto unlock_exit;
}
/* verify that we actually have some data to write */
if (count == 0) {
dbg(1, "%s: write request of 0 bytes", __func__);
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);
dbg(4, "%s: count = %Zd, bytes_to_write = %Zd", __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;
err("Couldn't submit interrupt_out_urb %d", retval);
goto unlock_exit;
}
retval = bytes_to_write;
unlock_exit:
/* unlock the device */
mutex_unlock(&dev->lock);
exit:
dbg(2, "%s: leave, return value %d", __func__, retval);
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;
dbg(4, "%s: enter, status %d", __func__, status);
lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
if (status) {
if (status == -ENOENT ||
status == -ECONNRESET ||
status == -ESHUTDOWN) {
goto exit;
} else {
dbg(1, "%s: nonzero status received: %d", __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;
dbg(3, "%s: received %d bytes", __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) {
err("%s: usb_submit_urb failed (%d)", __func__, retval);
}
}
exit:
dev->interrupt_in_done = 1;
wake_up_interruptible (&dev->read_wait);
lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
dbg(4, "%s: leave, status %d", __func__, status);
}
/**
* tower_interrupt_out_callback
*/
static void tower_interrupt_out_callback (struct urb *urb)
{
struct lego_usb_tower *dev = urb->context;
int status = urb->status;
dbg(4, "%s: enter, status %d", __func__, status);
lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
/* sync/async unlink faults aren't errors */
if (status && !(status == -ENOENT ||
status == -ECONNRESET ||
status == -ESHUTDOWN)) {
dbg(1, "%s - nonzero write bulk status received: %d",
__func__, status);
}
dev->interrupt_out_busy = 0;
wake_up_interruptible(&dev->write_wait);
lego_usb_tower_debug_data(5, __func__, urb->actual_length, urb->transfer_buffer);
dbg(4, "%s: leave, status %d", __func__, status);
}
/**
* 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 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;
dbg(2, "%s: enter", __func__);
if (udev == NULL)
dev_info(&interface->dev, "udev is NULL.\n");
/* allocate memory for our device state and initialize it */
dev = kmalloc (sizeof(struct lego_usb_tower), GFP_KERNEL);
if (dev == NULL) {
err ("Out of memory");
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) {
err("interrupt in endpoint not found");
goto error;
}
if (dev->interrupt_out_endpoint == NULL) {
err("interrupt out endpoint not found");
goto error;
}
dev->read_buffer = kmalloc (read_buffer_size, GFP_KERNEL);
if (!dev->read_buffer) {
err("Couldn't allocate read_buffer");
goto error;
}
dev->interrupt_in_buffer = kmalloc (le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize), GFP_KERNEL);
if (!dev->interrupt_in_buffer) {
err("Couldn't allocate interrupt_in_buffer");
goto error;
}
dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->interrupt_in_urb) {
err("Couldn't allocate interrupt_in_urb");
goto error;
}
dev->interrupt_out_buffer = kmalloc (write_buffer_size, GFP_KERNEL);
if (!dev->interrupt_out_buffer) {
err("Couldn't allocate interrupt_out_buffer");
goto error;
}
dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->interrupt_out_urb) {
err("Couldn't allocate interrupt_out_urb");
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 */
err ("Not able to get a minor for this device.");
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) {
err("LEGO USB Tower get version control request failed");
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:
dbg(2, "%s: leave, return value 0x%.8lx (dev)", __func__, (long) dev);
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;
dbg(2, "%s: enter", __func__);
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));
dbg(2, "%s: leave", __func__);
}
/**
* lego_usb_tower_init
*/
static int __init lego_usb_tower_init(void)
{
int result;
int retval = 0;
dbg(2, "%s: enter", __func__);
/* register this driver with the USB subsystem */
result = usb_register(&tower_driver);
if (result < 0) {
err("usb_register failed for the %s driver. Error number %d", __FILE__, result);
retval = -1;
goto exit;
}
printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
DRIVER_DESC "\n");
exit:
dbg(2, "%s: leave, return value %d", __func__, retval);
return retval;
}
/**
* lego_usb_tower_exit
*/
static void __exit lego_usb_tower_exit(void)
{
dbg(2, "%s: enter", __func__);
/* deregister this driver with the USB subsystem */
usb_deregister (&tower_driver);
dbg(2, "%s: leave", __func__);
}
module_init (lego_usb_tower_init);
module_exit (lego_usb_tower_exit);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
#ifdef MODULE_LICENSE
MODULE_LICENSE("GPL");
#endif
