aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/misc/ldusb.c
diff options
context:
space:
mode:
authorMichael Hund <mhund@ld-didactic.de>2005-06-27 22:44:22 +0200
committerGreg Kroah-Hartman <gregkh@suse.de>2005-07-12 11:52:57 -0700
commit2824bd250f0be1551747cc3ed5ae07facc285b57 (patch)
tree1dc604385c5324cc1175f86d0e87fab5dd3b5f8e /drivers/usb/misc/ldusb.c
parent83ef344a7539aa55a787790bc036f0bf3466e191 (diff)
[PATCH] USB: add ldusb driver
The following driver provides complete interrupt-in and interrupt-out reports (raw data) to a user program. Until now it uses the HIDIOCGDEVINFO ioctl call, because I don't know better :-(. Perhaps, it will be ok for you - and I will be happy, if you assign 8 minor numbers. I have tested it in several environments and it works very well for me. However, it has a problem with two or more devices at the same hub, if the two or more devices need 1 ms interrupt-in transfers. Unfortunately more than one interrupt-in transfer every ms isn't possible (ehci driver?). This is why the min_interrupt_in_interval and min_interrupt_out_interval are increased to 2 ms (see the corresponding module parameters). This way, I can use two devices simultaneously at the same hub. Signed-off-by: Michael Hund <mhund@ld-didactic.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/misc/ldusb.c')
-rw-r--r--drivers/usb/misc/ldusb.c794
1 files changed, 794 insertions, 0 deletions
diff --git a/drivers/usb/misc/ldusb.c b/drivers/usb/misc/ldusb.c
new file mode 100644
index 00000000000..66ec88354b9
--- /dev/null
+++ b/drivers/usb/misc/ldusb.c
@@ -0,0 +1,794 @@
+/**
+ * Generic USB driver for report based interrupt in/out devices
+ * like LD Didactic's USB devices. LD Didactic's USB devices are
+ * HID devices which do not use HID report definitons (they use
+ * raw interrupt in and our reports only for communication).
+ *
+ * This driver uses a ring buffer for time critical reading of
+ * interrupt in reports and provides read and write methods for
+ * raw interrupt reports (similar to the Windows HID driver).
+ * Devices based on the book USB COMPLETE by Jan Axelson may need
+ * such a compatibility to the Windows HID driver.
+ *
+ * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * Derived from Lego USB Tower driver
+ * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net>
+ * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
+ *
+ * V0.1 (mh) Initial version
+ * V0.11 (mh) Added raw support for HID 1.0 devices (no interrupt out endpoint)
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include <asm/uaccess.h>
+#include <linux/input.h>
+#include <linux/usb.h>
+#include <linux/poll.h>
+
+/* Define these values to match your devices */
+#define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */
+#define USB_DEVICE_ID_CASSY 0x1000 /* USB Product ID for all CASSY-S modules */
+#define USB_DEVICE_ID_POCKETCASSY 0x1010 /* USB Product ID for Pocket-CASSY */
+#define USB_DEVICE_ID_MOBILECASSY 0x1020 /* USB Product ID for Mobile-CASSY */
+#define USB_DEVICE_ID_JWM 0x1080 /* USB Product ID for Joule and Wattmeter */
+#define USB_DEVICE_ID_DMMP 0x1081 /* USB Product ID for Digital Multimeter P (reserved) */
+#define USB_DEVICE_ID_UMIP 0x1090 /* USB Product ID for UMI P */
+#define USB_DEVICE_ID_VIDEOCOM 0x1200 /* USB Product ID for VideoCom */
+#define USB_DEVICE_ID_COM3LAB 0x2000 /* USB Product ID for COM3LAB */
+#define USB_DEVICE_ID_TELEPORT 0x2010 /* USB Product ID for Terminal Adapter */
+#define USB_DEVICE_ID_NETWORKANALYSER 0x2020 /* USB Product ID for Network Analyser */
+#define USB_DEVICE_ID_POWERCONTROL 0x2030 /* USB Product ID for Controlling device for Power Electronics */
+
+#define USB_VENDOR_ID_VERNIER 0x08f7
+#define USB_DEVICE_ID_VERNIER_LABPRO 0x0001
+#define USB_DEVICE_ID_VERNIER_GOTEMP 0x0002
+#define USB_DEVICE_ID_VERNIER_SKIP 0x0003
+#define USB_DEVICE_ID_VERNIER_CYCLOPS 0x0004
+
+
+#ifdef CONFIG_USB_DYNAMIC_MINORS
+#define USB_LD_MINOR_BASE 0
+#else
+#define USB_LD_MINOR_BASE 176
+#endif
+
+/* table of devices that work with this driver */
+static struct usb_device_id ld_usb_table [] = {
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_CASSY) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_POCKETCASSY) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_MOBILECASSY) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_JWM) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_DMMP) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_UMIP) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_VIDEOCOM) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_COM3LAB) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_TELEPORT) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_NETWORKANALYSER) },
+ { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_POWERCONTROL) },
+ { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) },
+ { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) },
+ { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) },
+ { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) },
+ { } /* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, ld_usb_table);
+MODULE_VERSION("V0.11");
+MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
+MODULE_DESCRIPTION("LD USB Driver");
+MODULE_LICENSE("GPL");
+MODULE_SUPPORTED_DEVICE("LD USB Devices");
+
+#ifdef CONFIG_USB_DEBUG
+ static int debug = 1;
+#else
+ static int debug = 0;
+#endif
+
+/* Use our own dbg macro */
+#define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0)
+
+/* Module parameters */
+module_param(debug, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Debug enabled or not");
+
+/* All interrupt in transfers are collected in a ring buffer to
+ * avoid racing conditions and get better performance of the driver.
+ */
+static int ring_buffer_size = 128;
+module_param(ring_buffer_size, int, 0);
+MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
+
+/* The write_buffer can contain more than one interrupt out transfer.
+ */
+static int write_buffer_size = 10;
+module_param(write_buffer_size, int, 0);
+MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
+
+/* As of kernel version 2.6.4 ehci-hcd uses an
+ * "only one interrupt transfer per frame" shortcut
+ * to simplify the scheduling of periodic transfers.
+ * This conflicts with our standard 1ms intervals for in and out URBs.
+ * We use default intervals of 2ms for in and 2ms for out transfers,
+ * which should be fast enough.
+ * Increase the interval to allow more devices that do interrupt transfers,
+ * or set to 1 to use the standard interval from the endpoint descriptors.
+ */
+static int min_interrupt_in_interval = 2;
+module_param(min_interrupt_in_interval, int, 0);
+MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
+
+static int min_interrupt_out_interval = 2;
+module_param(min_interrupt_out_interval, int, 0);
+MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
+
+/* Structure to hold all of our device specific stuff */
+struct ld_usb {
+ struct semaphore sem; /* locks this structure */
+ struct usb_interface* intf; /* save off the usb interface pointer */
+
+ int open_count; /* number of times this port has been opened */
+
+ char* ring_buffer;
+ unsigned int ring_head;
+ unsigned int ring_tail;
+
+ wait_queue_head_t read_wait;
+ wait_queue_head_t write_wait;
+
+ char* interrupt_in_buffer;
+ struct usb_endpoint_descriptor* interrupt_in_endpoint;
+ struct urb* interrupt_in_urb;
+ int interrupt_in_interval;
+ size_t interrupt_in_endpoint_size;
+ int interrupt_in_running;
+ int interrupt_in_done;
+
+ char* interrupt_out_buffer;
+ struct usb_endpoint_descriptor* interrupt_out_endpoint;
+ struct urb* interrupt_out_urb;
+ int interrupt_out_interval;
+ size_t interrupt_out_endpoint_size;
+ int interrupt_out_busy;
+};
+
+/* prevent races between open() and disconnect() */
+static DECLARE_MUTEX(disconnect_sem);
+
+static struct usb_driver ld_usb_driver;
+
+/**
+ * ld_usb_abort_transfers
+ * aborts transfers and frees associated data structures
+ */
+static void ld_usb_abort_transfers(struct ld_usb *dev)
+{
+ /* shutdown transfer */
+ if (dev->interrupt_in_running) {
+ dev->interrupt_in_running = 0;
+ if (dev->intf)
+ usb_kill_urb(dev->interrupt_in_urb);
+ }
+ if (dev->interrupt_out_busy)
+ if (dev->intf)
+ usb_kill_urb(dev->interrupt_out_urb);
+}
+
+/**
+ * ld_usb_delete
+ */
+static void ld_usb_delete(struct ld_usb *dev)
+{
+ ld_usb_abort_transfers(dev);
+
+ /* free data structures */
+ usb_free_urb(dev->interrupt_in_urb);
+ usb_free_urb(dev->interrupt_out_urb);
+ kfree(dev->ring_buffer);
+ kfree(dev->interrupt_in_buffer);
+ kfree(dev->interrupt_out_buffer);
+ kfree(dev);
+}
+
+/**
+ * ld_usb_interrupt_in_callback
+ */
+static void ld_usb_interrupt_in_callback(struct urb *urb, struct pt_regs *regs)
+{
+ struct ld_usb *dev = urb->context;
+ size_t *actual_buffer;
+ unsigned int next_ring_head;
+ int retval;
+
+ if (urb->status) {
+ if (urb->status == -ENOENT ||
+ urb->status == -ECONNRESET ||
+ urb->status == -ESHUTDOWN) {
+ goto exit;
+ } else {
+ dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n",
+ __FUNCTION__, urb->status);
+ goto resubmit; /* maybe we can recover */
+ }
+ }
+
+ if (urb->actual_length > 0) {
+ next_ring_head = (dev->ring_head+1) % ring_buffer_size;
+ if (next_ring_head != dev->ring_tail) {
+ actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
+ /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
+ *actual_buffer = urb->actual_length;
+ memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
+ dev->ring_head = next_ring_head;
+ dbg_info(&dev->intf->dev, "%s: received %d bytes\n",
+ __FUNCTION__, urb->actual_length);
+ } else
+ dev_warn(&dev->intf->dev,
+ "Ring buffer overflow, %d bytes dropped\n",
+ urb->actual_length);
+ }
+
+resubmit:
+ /* resubmit if we're still running */
+ if (dev->interrupt_in_running && dev->intf) {
+ retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
+ if (retval)
+ dev_err(&dev->intf->dev,
+ "usb_submit_urb failed (%d)\n", retval);
+ }
+
+exit:
+ dev->interrupt_in_done = 1;
+ wake_up_interruptible(&dev->read_wait);
+}
+
+/**
+ * ld_usb_interrupt_out_callback
+ */
+static void ld_usb_interrupt_out_callback(struct urb *urb, struct pt_regs *regs)
+{
+ struct ld_usb *dev = urb->context;
+
+ /* sync/async unlink faults aren't errors */
+ if (urb->status && !(urb->status == -ENOENT ||
+ urb->status == -ECONNRESET ||
+ urb->status == -ESHUTDOWN))
+ dbg_info(&dev->intf->dev,
+ "%s - nonzero write interrupt status received: %d\n",
+ __FUNCTION__, urb->status);
+
+ dev->interrupt_out_busy = 0;
+ wake_up_interruptible(&dev->write_wait);
+}
+
+/**
+ * ld_usb_open
+ */
+static int ld_usb_open(struct inode *inode, struct file *file)
+{
+ struct ld_usb *dev;
+ int subminor;
+ int retval = 0;
+ struct usb_interface *interface;
+
+ nonseekable_open(inode, file);
+ subminor = iminor(inode);
+
+ down(&disconnect_sem);
+
+ interface = usb_find_interface(&ld_usb_driver, subminor);
+
+ if (!interface) {
+ err("%s - error, can't find device for minor %d\n",
+ __FUNCTION__, subminor);
+ retval = -ENODEV;
+ goto unlock_disconnect_exit;
+ }
+
+ dev = usb_get_intfdata(interface);
+
+ if (!dev) {
+ retval = -ENODEV;
+ goto unlock_disconnect_exit;
+ }
+
+ /* lock this device */
+ if (down_interruptible(&dev->sem)) {
+ retval = -ERESTARTSYS;
+ goto unlock_disconnect_exit;
+ }
+
+ /* allow opening only once */
+ if (dev->open_count) {
+ retval = -EBUSY;
+ goto unlock_exit;
+ }
+ dev->open_count = 1;
+
+ /* initialize in direction */
+ dev->ring_head = 0;
+ dev->ring_tail = 0;
+ usb_fill_int_urb(dev->interrupt_in_urb,
+ interface_to_usbdev(interface),
+ usb_rcvintpipe(interface_to_usbdev(interface),
+ dev->interrupt_in_endpoint->bEndpointAddress),
+ dev->interrupt_in_buffer,
+ dev->interrupt_in_endpoint_size,
+ ld_usb_interrupt_in_callback,
+ dev,
+ dev->interrupt_in_interval);
+
+ dev->interrupt_in_running = 1;
+ dev->interrupt_in_done = 0;
+
+ retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
+ if (retval) {
+ dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
+ dev->interrupt_in_running = 0;
+ dev->open_count = 0;
+ goto unlock_exit;
+ }
+
+ /* save device in the file's private structure */
+ file->private_data = dev;
+
+unlock_exit:
+ up(&dev->sem);
+
+unlock_disconnect_exit:
+ up(&disconnect_sem);
+
+ return retval;
+}
+
+/**
+ * ld_usb_release
+ */
+static int ld_usb_release(struct inode *inode, struct file *file)
+{
+ struct ld_usb *dev;
+ int retval = 0;
+
+ dev = file->private_data;
+
+ if (dev == NULL) {
+ retval = -ENODEV;
+ goto exit;
+ }
+
+ if (down_interruptible(&dev->sem)) {
+ retval = -ERESTARTSYS;
+ goto exit;
+ }
+
+ if (dev->open_count != 1) {
+ retval = -ENODEV;
+ goto unlock_exit;
+ }
+ if (dev->intf == NULL) {
+ /* the device was unplugged before the file was released */
+ up(&dev->sem);
+ /* unlock here as ld_usb_delete frees dev */
+ ld_usb_delete(dev);
+ goto exit;
+ }
+
+ /* wait until write transfer is finished */
+ if (dev->interrupt_out_busy)
+ wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
+ ld_usb_abort_transfers(dev);
+ dev->open_count = 0;
+
+unlock_exit:
+ up(&dev->sem);
+
+exit:
+ return retval;
+}
+
+/**
+ * ld_usb_poll
+ */
+static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
+{
+ struct ld_usb *dev;
+ unsigned int mask = 0;
+
+ dev = file->private_data;
+
+ poll_wait(file, &dev->read_wait, wait);
+ poll_wait(file, &dev->write_wait, wait);
+
+ if (dev->ring_head != dev->ring_tail)
+ mask |= POLLIN | POLLRDNORM;
+ if (!dev->interrupt_out_busy)
+ mask |= POLLOUT | POLLWRNORM;
+
+ return mask;
+}
+
+/**
+ * ld_usb_read
+ */
+static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
+ loff_t *ppos)
+{
+ struct ld_usb *dev;
+ size_t *actual_buffer;
+ size_t bytes_to_read;
+ int retval = 0;
+
+ dev = file->private_data;
+
+ /* verify that we actually have some data to read */
+ if (count == 0)
+ goto exit;
+
+ /* lock this object */
+ if (down_interruptible(&dev->sem)) {
+ retval = -ERESTARTSYS;
+ goto exit;
+ }
+
+ /* verify that the device wasn't unplugged */
+ if (dev->intf == NULL) {
+ retval = -ENODEV;
+ err("No device or device unplugged %d\n", retval);
+ goto unlock_exit;
+ }
+
+ /* wait for data */
+ if (dev->ring_head == dev->ring_tail) {
+ if (file->f_flags & O_NONBLOCK) {
+ retval = -EAGAIN;
+ goto unlock_exit;
+ }
+ retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
+ if (retval < 0)
+ goto unlock_exit;
+ }
+
+ /* actual_buffer contains actual_length + interrupt_in_buffer */
+ actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
+ bytes_to_read = min(count, *actual_buffer);
+ if (bytes_to_read < *actual_buffer)
+ dev_warn(&dev->intf->dev, "Read buffer overflow, %d bytes dropped\n",
+ *actual_buffer-bytes_to_read);
+
+ /* copy one interrupt_in_buffer from ring_buffer into userspace */
+ if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
+ retval = -EFAULT;
+ goto unlock_exit;
+ }
+ dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
+
+ retval = bytes_to_read;
+
+unlock_exit:
+ /* unlock the device */
+ up(&dev->sem);
+
+exit:
+ return retval;
+}
+
+/**
+ * ld_usb_write
+ */
+static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct ld_usb *dev;
+ size_t bytes_to_write;
+ int retval = 0;
+
+ dev = file->private_data;
+
+ /* verify that we actually have some data to write */
+ if (count == 0)
+ goto exit;
+
+ /* lock this object */
+ if (down_interruptible(&dev->sem)) {
+ retval = -ERESTARTSYS;
+ goto exit;
+ }
+
+ /* verify that the device wasn't unplugged */
+ if (dev->intf == NULL) {
+ retval = -ENODEV;
+ err("No device or device unplugged %d\n", retval);
+ goto unlock_exit;
+ }
+
+ /* wait until previous transfer is finished */
+ if (dev->interrupt_out_busy) {
+ if (file->f_flags & O_NONBLOCK) {
+ retval = -EAGAIN;
+ goto unlock_exit;
+ }
+ retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
+ if (retval < 0) {
+ goto unlock_exit;
+ }
+ }
+
+ /* write the data into interrupt_out_buffer from userspace */
+ bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
+ if (bytes_to_write < count)
+ dev_warn(&dev->intf->dev, "Write buffer overflow, %d bytes dropped\n",count-bytes_to_write);
+ dbg_info(&dev->intf->dev, "%s: count = %d, bytes_to_write = %d\n", __FUNCTION__, count, bytes_to_write);
+
+ if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
+ retval = -EFAULT;
+ goto unlock_exit;
+ }
+
+ if (dev->interrupt_out_endpoint == NULL) {
+ /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
+ retval = usb_control_msg(interface_to_usbdev(dev->intf),
+ usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
+ 9,
+ USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
+ 1 << 8, 0,
+ dev->interrupt_out_buffer,
+ bytes_to_write,
+ USB_CTRL_SET_TIMEOUT * HZ);
+ if (retval < 0)
+ err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval);
+ goto unlock_exit;
+ }
+
+ /* send off the urb */
+ usb_fill_int_urb(dev->interrupt_out_urb,
+ interface_to_usbdev(dev->intf),
+ usb_sndintpipe(interface_to_usbdev(dev->intf),
+ dev->interrupt_out_endpoint->bEndpointAddress),
+ dev->interrupt_out_buffer,
+ bytes_to_write,
+ ld_usb_interrupt_out_callback,
+ dev,
+ dev->interrupt_out_interval);
+
+ dev->interrupt_out_busy = 1;
+ wmb();
+
+ retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
+ if (retval) {
+ dev->interrupt_out_busy = 0;
+ err("Couldn't submit interrupt_out_urb %d\n", retval);
+ goto unlock_exit;
+ }
+ retval = bytes_to_write;
+
+unlock_exit:
+ /* unlock the device */
+ up(&dev->sem);
+
+exit:
+ return retval;
+}
+
+/* file operations needed when we register this driver */
+static struct file_operations ld_usb_fops = {
+ .owner = THIS_MODULE,
+ .read = ld_usb_read,
+ .write = ld_usb_write,
+ .open = ld_usb_open,
+ .release = ld_usb_release,
+ .poll = ld_usb_poll,
+};
+
+/*
+ * usb class driver info in order to get a minor number from the usb core,
+ * and to have the device registered with devfs and the driver core
+ */
+static struct usb_class_driver ld_usb_class = {
+ .name = "ldusb%d",
+ .fops = &ld_usb_fops,
+ .minor_base = USB_LD_MINOR_BASE,
+};
+
+/**
+ * ld_usb_probe
+ *
+ * Called by the usb core when a new device is connected that it thinks
+ * this driver might be interested in.
+ */
+static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
+{
+ struct usb_device *udev = interface_to_usbdev(intf);
+ struct ld_usb *dev = NULL;
+ struct usb_host_interface *iface_desc;
+ struct usb_endpoint_descriptor *endpoint;
+ char *buffer;
+ int i;
+ int retval = -ENOMEM;
+
+ /* allocate memory for our device state and intialize it */
+
+ dev = kmalloc(sizeof(*dev), GFP_KERNEL);
+ if (dev == NULL) {
+ dev_err(&intf->dev, "Out of memory\n");
+ goto exit;
+ }
+ memset(dev, 0x00, sizeof(*dev));
+ init_MUTEX(&dev->sem);
+ dev->intf = intf;
+ init_waitqueue_head(&dev->read_wait);
+ init_waitqueue_head(&dev->write_wait);
+
+ /* workaround for early firmware versions on fast computers */
+ if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
+ ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_CASSY) ||
+ (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_COM3LAB)) &&
+ (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
+ buffer = kmalloc(256, GFP_KERNEL);
+ /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
+ usb_string(udev, 255, buffer, 256);
+ kfree(buffer);
+ }
+
+ iface_desc = intf->cur_altsetting;
+
+ /* set up the endpoint information */
+ for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+ endpoint = &iface_desc->endpoint[i].desc;
+
+ if (((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN) &&
+ ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)) {
+ dev->interrupt_in_endpoint = endpoint;
+ }
+
+ if (((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT) &&
+ ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)) {
+ dev->interrupt_out_endpoint = endpoint;
+ }
+ }
+ if (dev->interrupt_in_endpoint == NULL) {
+ dev_err(&intf->dev, "Interrupt in endpoint not found\n");
+ goto error;
+ }
+ if (dev->interrupt_out_endpoint == NULL)
+ dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
+
+ dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
+ dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
+ if (!dev->ring_buffer) {
+ dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
+ goto error;
+ }
+ dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
+ if (!dev->interrupt_in_buffer) {
+ dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
+ goto error;
+ }
+ dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!dev->interrupt_in_urb) {
+ dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
+ goto error;
+ }
+ dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) :
+ udev->descriptor.bMaxPacketSize0;
+ dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
+ if (!dev->interrupt_out_buffer) {
+ dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
+ goto error;
+ }
+ dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!dev->interrupt_out_urb) {
+ dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
+ goto error;
+ }
+ dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
+ if (dev->interrupt_out_endpoint)
+ dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
+
+ /* we can register the device now, as it is ready */
+ usb_set_intfdata(intf, dev);
+
+ retval = usb_register_dev(intf, &ld_usb_class);
+ if (retval) {
+ /* something prevented us from registering this driver */
+ dev_err(&intf->dev, "Not able to get a minor for this device.\n");
+ usb_set_intfdata(intf, NULL);
+ goto error;
+ }
+
+ /* let the user know what node this device is now attached to */
+ dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
+ (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
+
+exit:
+ return retval;
+
+error:
+ ld_usb_delete(dev);
+
+ return retval;
+}
+
+/**
+ * ld_usb_disconnect
+ *
+ * Called by the usb core when the device is removed from the system.
+ */
+static void ld_usb_disconnect(struct usb_interface *intf)
+{
+ struct ld_usb *dev;
+ int minor;
+
+ down(&disconnect_sem);
+
+ dev = usb_get_intfdata(intf);
+ usb_set_intfdata(intf, NULL);
+
+ down(&dev->sem);
+
+ minor = intf->minor;
+
+ /* give back our minor */
+ usb_deregister_dev(intf, &ld_usb_class);
+
+ /* if the device is not opened, then we clean up right now */
+ if (!dev->open_count) {
+ up(&dev->sem);
+ ld_usb_delete(dev);
+ } else {
+ dev->intf = NULL;
+ up(&dev->sem);
+ }
+
+ up(&disconnect_sem);
+
+ dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
+ (minor - USB_LD_MINOR_BASE));
+}
+
+/* usb specific object needed to register this driver with the usb subsystem */
+static struct usb_driver ld_usb_driver = {
+ .owner = THIS_MODULE,
+ .name = "ldusb",
+ .probe = ld_usb_probe,
+ .disconnect = ld_usb_disconnect,
+ .id_table = ld_usb_table,
+};
+
+/**
+ * ld_usb_init
+ */
+static int __init ld_usb_init(void)
+{
+ int retval;
+
+ /* register this driver with the USB subsystem */
+ retval = usb_register(&ld_usb_driver);
+ if (retval)
+ err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval);
+
+ return retval;
+}
+
+/**
+ * ld_usb_exit
+ */
+static void __exit ld_usb_exit(void)
+{
+ /* deregister this driver with the USB subsystem */
+ usb_deregister(&ld_usb_driver);
+}
+
+module_init(ld_usb_init);
+module_exit(ld_usb_exit);
+