--- /dev/null
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/errno.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>
+
+
+/* Version Information */
+#define DRIVER_VERSION "v0.96"
+#define DRIVER_AUTHOR "Juergen Stuber <starblue@sourceforge.net>"
+#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) {
+ pr_err("error, can't find device for minor %d\n", 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;
+ pr_err("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 + msecs_to_jiffies(read_timeout);
+ }
+
+ /* 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 + msecs_to_jiffies(read_timeout);
+ }
+ /* 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:
+ 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;
+ pr_err("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 {
+ pr_warn("read_buffer overflow, %d bytes dropped\n",
+ 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 = msecs_to_jiffies(packet_timeout);
+ 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
Code Review / kvmfornfv.git / blobdiff