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path: root/drivers/usb/misc/iowarrior.c
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Diffstat (limited to 'drivers/usb/misc/iowarrior.c')
-rw-r--r--drivers/usb/misc/iowarrior.c926
1 files changed, 926 insertions, 0 deletions
diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
new file mode 100644
index 000000000..b421f1326
--- /dev/null
+++ b/drivers/usb/misc/iowarrior.c
@@ -0,0 +1,926 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Native support for the I/O-Warrior USB devices
+ *
+ * Copyright (c) 2003-2005, 2020 Code Mercenaries GmbH
+ * written by Christian Lucht <lucht@codemercs.com> and
+ * Christoph Jung <jung@codemercs.com>
+ *
+ * based on
+
+ * usb-skeleton.c by Greg Kroah-Hartman <greg@kroah.com>
+ * brlvger.c by Stephane Dalton <sdalton@videotron.ca>
+ * and Stephane Doyon <s.doyon@videotron.ca>
+ *
+ * Released under the GPLv2.
+ */
+
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/mutex.h>
+#include <linux/poll.h>
+#include <linux/usb/iowarrior.h>
+
+#define DRIVER_AUTHOR "Christian Lucht <lucht@codemercs.com>"
+#define DRIVER_DESC "USB IO-Warrior driver"
+
+#define USB_VENDOR_ID_CODEMERCS 1984
+/* low speed iowarrior */
+#define USB_DEVICE_ID_CODEMERCS_IOW40 0x1500
+#define USB_DEVICE_ID_CODEMERCS_IOW24 0x1501
+#define USB_DEVICE_ID_CODEMERCS_IOWPV1 0x1511
+#define USB_DEVICE_ID_CODEMERCS_IOWPV2 0x1512
+/* full speed iowarrior */
+#define USB_DEVICE_ID_CODEMERCS_IOW56 0x1503
+/* fuller speed iowarrior */
+#define USB_DEVICE_ID_CODEMERCS_IOW28 0x1504
+#define USB_DEVICE_ID_CODEMERCS_IOW28L 0x1505
+#define USB_DEVICE_ID_CODEMERCS_IOW100 0x1506
+
+/* OEMed devices */
+#define USB_DEVICE_ID_CODEMERCS_IOW24SAG 0x158a
+#define USB_DEVICE_ID_CODEMERCS_IOW56AM 0x158b
+
+/* Get a minor range for your devices from the usb maintainer */
+#ifdef CONFIG_USB_DYNAMIC_MINORS
+#define IOWARRIOR_MINOR_BASE 0
+#else
+#define IOWARRIOR_MINOR_BASE 208 // SKELETON_MINOR_BASE 192 + 16, not official yet
+#endif
+
+/* interrupt input queue size */
+#define MAX_INTERRUPT_BUFFER 16
+/*
+ maximum number of urbs that are submitted for writes at the same time,
+ this applies to the IOWarrior56 only!
+ IOWarrior24 and IOWarrior40 use synchronous usb_control_msg calls.
+*/
+#define MAX_WRITES_IN_FLIGHT 4
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+static struct usb_driver iowarrior_driver;
+
+/*--------------*/
+/* data */
+/*--------------*/
+
+/* Structure to hold all of our device specific stuff */
+struct iowarrior {
+ struct mutex mutex; /* locks this structure */
+ struct usb_device *udev; /* save off the usb device pointer */
+ struct usb_interface *interface; /* the interface for this device */
+ unsigned char minor; /* the starting minor number for this device */
+ struct usb_endpoint_descriptor *int_out_endpoint; /* endpoint for reading (needed for IOW56 only) */
+ struct usb_endpoint_descriptor *int_in_endpoint; /* endpoint for reading */
+ struct urb *int_in_urb; /* the urb for reading data */
+ unsigned char *int_in_buffer; /* buffer for data to be read */
+ unsigned char serial_number; /* to detect lost packages */
+ unsigned char *read_queue; /* size is MAX_INTERRUPT_BUFFER * packet size */
+ wait_queue_head_t read_wait;
+ wait_queue_head_t write_wait; /* wait-queue for writing to the device */
+ atomic_t write_busy; /* number of write-urbs submitted */
+ atomic_t read_idx;
+ atomic_t intr_idx;
+ atomic_t overflow_flag; /* signals an index 'rollover' */
+ int present; /* this is 1 as long as the device is connected */
+ int opened; /* this is 1 if the device is currently open */
+ char chip_serial[9]; /* the serial number string of the chip connected */
+ int report_size; /* number of bytes in a report */
+ u16 product_id;
+ struct usb_anchor submitted;
+};
+
+/*--------------*/
+/* globals */
+/*--------------*/
+
+#define USB_REQ_GET_REPORT 0x01
+//#if 0
+static int usb_get_report(struct usb_device *dev,
+ struct usb_host_interface *inter, unsigned char type,
+ unsigned char id, void *buf, int size)
+{
+ return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
+ USB_REQ_GET_REPORT,
+ USB_DIR_IN | USB_TYPE_CLASS |
+ USB_RECIP_INTERFACE, (type << 8) + id,
+ inter->desc.bInterfaceNumber, buf, size,
+ USB_CTRL_GET_TIMEOUT);
+}
+//#endif
+
+#define USB_REQ_SET_REPORT 0x09
+
+static int usb_set_report(struct usb_interface *intf, unsigned char type,
+ unsigned char id, void *buf, int size)
+{
+ return usb_control_msg(interface_to_usbdev(intf),
+ usb_sndctrlpipe(interface_to_usbdev(intf), 0),
+ USB_REQ_SET_REPORT,
+ USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+ (type << 8) + id,
+ intf->cur_altsetting->desc.bInterfaceNumber, buf,
+ size, 1000);
+}
+
+/*---------------------*/
+/* driver registration */
+/*---------------------*/
+/* table of devices that work with this driver */
+static const struct usb_device_id iowarrior_ids[] = {
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW40)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV1)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOWPV2)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW24SAG)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW56AM)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW28L)},
+ {USB_DEVICE(USB_VENDOR_ID_CODEMERCS, USB_DEVICE_ID_CODEMERCS_IOW100)},
+ {} /* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, iowarrior_ids);
+
+/*
+ * USB callback handler for reading data
+ */
+static void iowarrior_callback(struct urb *urb)
+{
+ struct iowarrior *dev = urb->context;
+ int intr_idx;
+ int read_idx;
+ int aux_idx;
+ int offset;
+ int status = urb->status;
+ int retval;
+
+ switch (status) {
+ case 0:
+ /* success */
+ break;
+ case -ECONNRESET:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ return;
+ default:
+ goto exit;
+ }
+
+ intr_idx = atomic_read(&dev->intr_idx);
+ /* aux_idx become previous intr_idx */
+ aux_idx = (intr_idx == 0) ? (MAX_INTERRUPT_BUFFER - 1) : (intr_idx - 1);
+ read_idx = atomic_read(&dev->read_idx);
+
+ /* queue is not empty and it's interface 0 */
+ if ((intr_idx != read_idx)
+ && (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0)) {
+ /* + 1 for serial number */
+ offset = aux_idx * (dev->report_size + 1);
+ if (!memcmp
+ (dev->read_queue + offset, urb->transfer_buffer,
+ dev->report_size)) {
+ /* equal values on interface 0 will be ignored */
+ goto exit;
+ }
+ }
+
+ /* aux_idx become next intr_idx */
+ aux_idx = (intr_idx == (MAX_INTERRUPT_BUFFER - 1)) ? 0 : (intr_idx + 1);
+ if (read_idx == aux_idx) {
+ /* queue full, dropping oldest input */
+ read_idx = (++read_idx == MAX_INTERRUPT_BUFFER) ? 0 : read_idx;
+ atomic_set(&dev->read_idx, read_idx);
+ atomic_set(&dev->overflow_flag, 1);
+ }
+
+ /* +1 for serial number */
+ offset = intr_idx * (dev->report_size + 1);
+ memcpy(dev->read_queue + offset, urb->transfer_buffer,
+ dev->report_size);
+ *(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
+
+ atomic_set(&dev->intr_idx, aux_idx);
+ /* tell the blocking read about the new data */
+ wake_up_interruptible(&dev->read_wait);
+
+exit:
+ retval = usb_submit_urb(urb, GFP_ATOMIC);
+ if (retval)
+ dev_err(&dev->interface->dev, "%s - usb_submit_urb failed with result %d\n",
+ __func__, retval);
+
+}
+
+/*
+ * USB Callback handler for write-ops
+ */
+static void iowarrior_write_callback(struct urb *urb)
+{
+ struct iowarrior *dev;
+ int status = urb->status;
+
+ dev = urb->context;
+ /* sync/async unlink faults aren't errors */
+ if (status &&
+ !(status == -ENOENT ||
+ status == -ECONNRESET || status == -ESHUTDOWN)) {
+ dev_dbg(&dev->interface->dev,
+ "nonzero write bulk status received: %d\n", status);
+ }
+ /* free up our allocated buffer */
+ usb_free_coherent(urb->dev, urb->transfer_buffer_length,
+ urb->transfer_buffer, urb->transfer_dma);
+ /* tell a waiting writer the interrupt-out-pipe is available again */
+ atomic_dec(&dev->write_busy);
+ wake_up_interruptible(&dev->write_wait);
+}
+
+/*
+ * iowarrior_delete
+ */
+static inline void iowarrior_delete(struct iowarrior *dev)
+{
+ dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
+ kfree(dev->int_in_buffer);
+ usb_free_urb(dev->int_in_urb);
+ kfree(dev->read_queue);
+ usb_put_intf(dev->interface);
+ kfree(dev);
+}
+
+/*---------------------*/
+/* fops implementation */
+/*---------------------*/
+
+static int read_index(struct iowarrior *dev)
+{
+ int intr_idx, read_idx;
+
+ read_idx = atomic_read(&dev->read_idx);
+ intr_idx = atomic_read(&dev->intr_idx);
+
+ return (read_idx == intr_idx ? -1 : read_idx);
+}
+
+/*
+ * iowarrior_read
+ */
+static ssize_t iowarrior_read(struct file *file, char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct iowarrior *dev;
+ int read_idx;
+ int offset;
+
+ dev = file->private_data;
+
+ /* verify that the device wasn't unplugged */
+ if (!dev || !dev->present)
+ return -ENODEV;
+
+ dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
+ dev->minor, count);
+
+ /* read count must be packet size (+ time stamp) */
+ if ((count != dev->report_size)
+ && (count != (dev->report_size + 1)))
+ return -EINVAL;
+
+ /* repeat until no buffer overrun in callback handler occur */
+ do {
+ atomic_set(&dev->overflow_flag, 0);
+ if ((read_idx = read_index(dev)) == -1) {
+ /* queue empty */
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+ else {
+ //next line will return when there is either new data, or the device is unplugged
+ int r = wait_event_interruptible(dev->read_wait,
+ (!dev->present
+ || (read_idx =
+ read_index
+ (dev)) !=
+ -1));
+ if (r) {
+ //we were interrupted by a signal
+ return -ERESTART;
+ }
+ if (!dev->present) {
+ //The device was unplugged
+ return -ENODEV;
+ }
+ if (read_idx == -1) {
+ // Can this happen ???
+ return 0;
+ }
+ }
+ }
+
+ offset = read_idx * (dev->report_size + 1);
+ if (copy_to_user(buffer, dev->read_queue + offset, count)) {
+ return -EFAULT;
+ }
+ } while (atomic_read(&dev->overflow_flag));
+
+ read_idx = ++read_idx == MAX_INTERRUPT_BUFFER ? 0 : read_idx;
+ atomic_set(&dev->read_idx, read_idx);
+ return count;
+}
+
+/*
+ * iowarrior_write
+ */
+static ssize_t iowarrior_write(struct file *file,
+ const char __user *user_buffer,
+ size_t count, loff_t *ppos)
+{
+ struct iowarrior *dev;
+ int retval = 0;
+ char *buf = NULL; /* for IOW24 and IOW56 we need a buffer */
+ struct urb *int_out_urb = NULL;
+
+ dev = file->private_data;
+
+ mutex_lock(&dev->mutex);
+ /* verify that the device wasn't unplugged */
+ if (!dev->present) {
+ retval = -ENODEV;
+ goto exit;
+ }
+ dev_dbg(&dev->interface->dev, "minor %d, count = %zd\n",
+ dev->minor, count);
+ /* if count is 0 we're already done */
+ if (count == 0) {
+ retval = 0;
+ goto exit;
+ }
+ /* We only accept full reports */
+ if (count != dev->report_size) {
+ retval = -EINVAL;
+ goto exit;
+ }
+ switch (dev->product_id) {
+ case USB_DEVICE_ID_CODEMERCS_IOW24:
+ case USB_DEVICE_ID_CODEMERCS_IOW24SAG:
+ case USB_DEVICE_ID_CODEMERCS_IOWPV1:
+ case USB_DEVICE_ID_CODEMERCS_IOWPV2:
+ case USB_DEVICE_ID_CODEMERCS_IOW40:
+ /* IOW24 and IOW40 use a synchronous call */
+ buf = memdup_user(user_buffer, count);
+ if (IS_ERR(buf)) {
+ retval = PTR_ERR(buf);
+ goto exit;
+ }
+ retval = usb_set_report(dev->interface, 2, 0, buf, count);
+ kfree(buf);
+ goto exit;
+ case USB_DEVICE_ID_CODEMERCS_IOW56:
+ case USB_DEVICE_ID_CODEMERCS_IOW56AM:
+ case USB_DEVICE_ID_CODEMERCS_IOW28:
+ case USB_DEVICE_ID_CODEMERCS_IOW28L:
+ case USB_DEVICE_ID_CODEMERCS_IOW100:
+ /* The IOW56 uses asynchronous IO and more urbs */
+ if (atomic_read(&dev->write_busy) == MAX_WRITES_IN_FLIGHT) {
+ /* Wait until we are below the limit for submitted urbs */
+ if (file->f_flags & O_NONBLOCK) {
+ retval = -EAGAIN;
+ goto exit;
+ } else {
+ retval = wait_event_interruptible(dev->write_wait,
+ (!dev->present || (atomic_read (&dev-> write_busy) < MAX_WRITES_IN_FLIGHT)));
+ if (retval) {
+ /* we were interrupted by a signal */
+ retval = -ERESTART;
+ goto exit;
+ }
+ if (!dev->present) {
+ /* The device was unplugged */
+ retval = -ENODEV;
+ goto exit;
+ }
+ if (!dev->opened) {
+ /* We were closed while waiting for an URB */
+ retval = -ENODEV;
+ goto exit;
+ }
+ }
+ }
+ atomic_inc(&dev->write_busy);
+ int_out_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!int_out_urb) {
+ retval = -ENOMEM;
+ goto error_no_urb;
+ }
+ buf = usb_alloc_coherent(dev->udev, dev->report_size,
+ GFP_KERNEL, &int_out_urb->transfer_dma);
+ if (!buf) {
+ retval = -ENOMEM;
+ dev_dbg(&dev->interface->dev,
+ "Unable to allocate buffer\n");
+ goto error_no_buffer;
+ }
+ usb_fill_int_urb(int_out_urb, dev->udev,
+ usb_sndintpipe(dev->udev,
+ dev->int_out_endpoint->bEndpointAddress),
+ buf, dev->report_size,
+ iowarrior_write_callback, dev,
+ dev->int_out_endpoint->bInterval);
+ int_out_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+ if (copy_from_user(buf, user_buffer, count)) {
+ retval = -EFAULT;
+ goto error;
+ }
+ usb_anchor_urb(int_out_urb, &dev->submitted);
+ retval = usb_submit_urb(int_out_urb, GFP_KERNEL);
+ if (retval) {
+ dev_dbg(&dev->interface->dev,
+ "submit error %d for urb nr.%d\n",
+ retval, atomic_read(&dev->write_busy));
+ usb_unanchor_urb(int_out_urb);
+ goto error;
+ }
+ /* submit was ok */
+ retval = count;
+ usb_free_urb(int_out_urb);
+ goto exit;
+ default:
+ /* what do we have here ? An unsupported Product-ID ? */
+ dev_err(&dev->interface->dev, "%s - not supported for product=0x%x\n",
+ __func__, dev->product_id);
+ retval = -EFAULT;
+ goto exit;
+ }
+error:
+ usb_free_coherent(dev->udev, dev->report_size, buf,
+ int_out_urb->transfer_dma);
+error_no_buffer:
+ usb_free_urb(int_out_urb);
+error_no_urb:
+ atomic_dec(&dev->write_busy);
+ wake_up_interruptible(&dev->write_wait);
+exit:
+ mutex_unlock(&dev->mutex);
+ return retval;
+}
+
+/*
+ * iowarrior_ioctl
+ */
+static long iowarrior_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct iowarrior *dev = NULL;
+ __u8 *buffer;
+ __u8 __user *user_buffer;
+ int retval;
+ int io_res; /* checks for bytes read/written and copy_to/from_user results */
+
+ dev = file->private_data;
+ if (!dev)
+ return -ENODEV;
+
+ buffer = kzalloc(dev->report_size, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ mutex_lock(&dev->mutex);
+
+ /* verify that the device wasn't unplugged */
+ if (!dev->present) {
+ retval = -ENODEV;
+ goto error_out;
+ }
+
+ dev_dbg(&dev->interface->dev, "minor %d, cmd 0x%.4x, arg %ld\n",
+ dev->minor, cmd, arg);
+
+ retval = 0;
+ io_res = 0;
+ switch (cmd) {
+ case IOW_WRITE:
+ if (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24 ||
+ dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW24SAG ||
+ dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV1 ||
+ dev->product_id == USB_DEVICE_ID_CODEMERCS_IOWPV2 ||
+ dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW40) {
+ user_buffer = (__u8 __user *)arg;
+ io_res = copy_from_user(buffer, user_buffer,
+ dev->report_size);
+ if (io_res) {
+ retval = -EFAULT;
+ } else {
+ io_res = usb_set_report(dev->interface, 2, 0,
+ buffer,
+ dev->report_size);
+ if (io_res < 0)
+ retval = io_res;
+ }
+ } else {
+ retval = -EINVAL;
+ dev_err(&dev->interface->dev,
+ "ioctl 'IOW_WRITE' is not supported for product=0x%x.\n",
+ dev->product_id);
+ }
+ break;
+ case IOW_READ:
+ user_buffer = (__u8 __user *)arg;
+ io_res = usb_get_report(dev->udev,
+ dev->interface->cur_altsetting, 1, 0,
+ buffer, dev->report_size);
+ if (io_res < 0)
+ retval = io_res;
+ else {
+ io_res = copy_to_user(user_buffer, buffer, dev->report_size);
+ if (io_res)
+ retval = -EFAULT;
+ }
+ break;
+ case IOW_GETINFO:
+ {
+ /* Report available information for the device */
+ struct iowarrior_info info;
+ /* needed for power consumption */
+ struct usb_config_descriptor *cfg_descriptor = &dev->udev->actconfig->desc;
+
+ memset(&info, 0, sizeof(info));
+ /* directly from the descriptor */
+ info.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
+ info.product = dev->product_id;
+ info.revision = le16_to_cpu(dev->udev->descriptor.bcdDevice);
+
+ /* 0==UNKNOWN, 1==LOW(usb1.1) ,2=FULL(usb1.1), 3=HIGH(usb2.0) */
+ info.speed = dev->udev->speed;
+ info.if_num = dev->interface->cur_altsetting->desc.bInterfaceNumber;
+ info.report_size = dev->report_size;
+
+ /* serial number string has been read earlier 8 chars or empty string */
+ memcpy(info.serial, dev->chip_serial,
+ sizeof(dev->chip_serial));
+ if (cfg_descriptor == NULL) {
+ info.power = -1; /* no information available */
+ } else {
+ /* the MaxPower is stored in units of 2mA to make it fit into a byte-value */
+ info.power = cfg_descriptor->bMaxPower * 2;
+ }
+ io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
+ sizeof(struct iowarrior_info));
+ if (io_res)
+ retval = -EFAULT;
+ break;
+ }
+ default:
+ /* return that we did not understand this ioctl call */
+ retval = -ENOTTY;
+ break;
+ }
+error_out:
+ /* unlock the device */
+ mutex_unlock(&dev->mutex);
+ kfree(buffer);
+ return retval;
+}
+
+/*
+ * iowarrior_open
+ */
+static int iowarrior_open(struct inode *inode, struct file *file)
+{
+ struct iowarrior *dev = NULL;
+ struct usb_interface *interface;
+ int subminor;
+ int retval = 0;
+
+ subminor = iminor(inode);
+
+ interface = usb_find_interface(&iowarrior_driver, subminor);
+ if (!interface) {
+ pr_err("%s - error, can't find device for minor %d\n",
+ __func__, subminor);
+ return -ENODEV;
+ }
+
+ dev = usb_get_intfdata(interface);
+ if (!dev)
+ return -ENODEV;
+
+ mutex_lock(&dev->mutex);
+
+ /* Only one process can open each device, no sharing. */
+ if (dev->opened) {
+ retval = -EBUSY;
+ goto out;
+ }
+
+ /* setup interrupt handler for receiving values */
+ if ((retval = usb_submit_urb(dev->int_in_urb, GFP_KERNEL)) < 0) {
+ dev_err(&interface->dev, "Error %d while submitting URB\n", retval);
+ retval = -EFAULT;
+ goto out;
+ }
+ /* increment our usage count for the driver */
+ ++dev->opened;
+ /* save our object in the file's private structure */
+ file->private_data = dev;
+ retval = 0;
+
+out:
+ mutex_unlock(&dev->mutex);
+ return retval;
+}
+
+/*
+ * iowarrior_release
+ */
+static int iowarrior_release(struct inode *inode, struct file *file)
+{
+ struct iowarrior *dev;
+ int retval = 0;
+
+ dev = file->private_data;
+ if (!dev)
+ return -ENODEV;
+
+ dev_dbg(&dev->interface->dev, "minor %d\n", dev->minor);
+
+ /* lock our device */
+ mutex_lock(&dev->mutex);
+
+ if (dev->opened <= 0) {
+ retval = -ENODEV; /* close called more than once */
+ mutex_unlock(&dev->mutex);
+ } else {
+ dev->opened = 0; /* we're closing now */
+ retval = 0;
+ if (dev->present) {
+ /*
+ The device is still connected so we only shutdown
+ pending read-/write-ops.
+ */
+ usb_kill_urb(dev->int_in_urb);
+ wake_up_interruptible(&dev->read_wait);
+ wake_up_interruptible(&dev->write_wait);
+ mutex_unlock(&dev->mutex);
+ } else {
+ /* The device was unplugged, cleanup resources */
+ mutex_unlock(&dev->mutex);
+ iowarrior_delete(dev);
+ }
+ }
+ return retval;
+}
+
+static __poll_t iowarrior_poll(struct file *file, poll_table * wait)
+{
+ struct iowarrior *dev = file->private_data;
+ __poll_t mask = 0;
+
+ if (!dev->present)
+ return EPOLLERR | EPOLLHUP;
+
+ poll_wait(file, &dev->read_wait, wait);
+ poll_wait(file, &dev->write_wait, wait);
+
+ if (!dev->present)
+ return EPOLLERR | EPOLLHUP;
+
+ if (read_index(dev) != -1)
+ mask |= EPOLLIN | EPOLLRDNORM;
+
+ if (atomic_read(&dev->write_busy) < MAX_WRITES_IN_FLIGHT)
+ mask |= EPOLLOUT | EPOLLWRNORM;
+ return mask;
+}
+
+/*
+ * File operations needed when we register this driver.
+ * This assumes that this driver NEEDS file operations,
+ * of course, which means that the driver is expected
+ * to have a node in the /dev directory. If the USB
+ * device were for a network interface then the driver
+ * would use "struct net_driver" instead, and a serial
+ * device would use "struct tty_driver".
+ */
+static const struct file_operations iowarrior_fops = {
+ .owner = THIS_MODULE,
+ .write = iowarrior_write,
+ .read = iowarrior_read,
+ .unlocked_ioctl = iowarrior_ioctl,
+ .open = iowarrior_open,
+ .release = iowarrior_release,
+ .poll = iowarrior_poll,
+ .llseek = noop_llseek,
+};
+
+static char *iowarrior_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 devfs and the driver core
+ */
+static struct usb_class_driver iowarrior_class = {
+ .name = "iowarrior%d",
+ .devnode = iowarrior_devnode,
+ .fops = &iowarrior_fops,
+ .minor_base = IOWARRIOR_MINOR_BASE,
+};
+
+/*---------------------------------*/
+/* probe and disconnect functions */
+/*---------------------------------*/
+/*
+ * iowarrior_probe
+ *
+ * Called by the usb core when a new device is connected that it thinks
+ * this driver might be interested in.
+ */
+static int iowarrior_probe(struct usb_interface *interface,
+ const struct usb_device_id *id)
+{
+ struct usb_device *udev = interface_to_usbdev(interface);
+ struct iowarrior *dev = NULL;
+ struct usb_host_interface *iface_desc;
+ int retval = -ENOMEM;
+ int res;
+
+ /* allocate memory for our device state and initialize it */
+ dev = kzalloc(sizeof(struct iowarrior), GFP_KERNEL);
+ if (!dev)
+ return retval;
+
+ mutex_init(&dev->mutex);
+
+ atomic_set(&dev->intr_idx, 0);
+ atomic_set(&dev->read_idx, 0);
+ atomic_set(&dev->overflow_flag, 0);
+ init_waitqueue_head(&dev->read_wait);
+ atomic_set(&dev->write_busy, 0);
+ init_waitqueue_head(&dev->write_wait);
+
+ dev->udev = udev;
+ dev->interface = usb_get_intf(interface);
+
+ iface_desc = interface->cur_altsetting;
+ dev->product_id = le16_to_cpu(udev->descriptor.idProduct);
+
+ init_usb_anchor(&dev->submitted);
+
+ res = usb_find_last_int_in_endpoint(iface_desc, &dev->int_in_endpoint);
+ if (res) {
+ dev_err(&interface->dev, "no interrupt-in endpoint found\n");
+ retval = res;
+ goto error;
+ }
+
+ if ((dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56) ||
+ (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW56AM) ||
+ (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28) ||
+ (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW28L) ||
+ (dev->product_id == USB_DEVICE_ID_CODEMERCS_IOW100)) {
+ res = usb_find_last_int_out_endpoint(iface_desc,
+ &dev->int_out_endpoint);
+ if (res) {
+ dev_err(&interface->dev, "no interrupt-out endpoint found\n");
+ retval = res;
+ goto error;
+ }
+ }
+
+ /* we have to check the report_size often, so remember it in the endianness suitable for our machine */
+ dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint);
+
+ /*
+ * Some devices need the report size to be different than the
+ * endpoint size.
+ */
+ if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
+ switch (dev->product_id) {
+ case USB_DEVICE_ID_CODEMERCS_IOW56:
+ case USB_DEVICE_ID_CODEMERCS_IOW56AM:
+ dev->report_size = 7;
+ break;
+
+ case USB_DEVICE_ID_CODEMERCS_IOW28:
+ case USB_DEVICE_ID_CODEMERCS_IOW28L:
+ dev->report_size = 4;
+ break;
+
+ case USB_DEVICE_ID_CODEMERCS_IOW100:
+ dev->report_size = 12;
+ break;
+ }
+ }
+
+ /* create the urb and buffer for reading */
+ dev->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!dev->int_in_urb)
+ goto error;
+ dev->int_in_buffer = kmalloc(dev->report_size, GFP_KERNEL);
+ if (!dev->int_in_buffer)
+ goto error;
+ usb_fill_int_urb(dev->int_in_urb, dev->udev,
+ usb_rcvintpipe(dev->udev,
+ dev->int_in_endpoint->bEndpointAddress),
+ dev->int_in_buffer, dev->report_size,
+ iowarrior_callback, dev,
+ dev->int_in_endpoint->bInterval);
+ /* create an internal buffer for interrupt data from the device */
+ dev->read_queue =
+ kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER,
+ GFP_KERNEL);
+ if (!dev->read_queue)
+ goto error;
+ /* Get the serial-number of the chip */
+ memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
+ usb_string(udev, udev->descriptor.iSerialNumber, dev->chip_serial,
+ sizeof(dev->chip_serial));
+ if (strlen(dev->chip_serial) != 8)
+ memset(dev->chip_serial, 0x00, sizeof(dev->chip_serial));
+
+ /* Set the idle timeout to 0, if this is interface 0 */
+ if (dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) {
+ usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+ 0x0A,
+ USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
+ 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
+ }
+ /* allow device read and ioctl */
+ dev->present = 1;
+
+ /* we can register the device now, as it is ready */
+ usb_set_intfdata(interface, dev);
+
+ retval = usb_register_dev(interface, &iowarrior_class);
+ if (retval) {
+ /* something prevented us from registering this driver */
+ dev_err(&interface->dev, "Not able to get a minor for this device.\n");
+ goto error;
+ }
+
+ dev->minor = interface->minor;
+
+ /* let the user know what node this device is now attached to */
+ dev_info(&interface->dev, "IOWarrior product=0x%x, serial=%s interface=%d "
+ "now attached to iowarrior%d\n", dev->product_id, dev->chip_serial,
+ iface_desc->desc.bInterfaceNumber, dev->minor - IOWARRIOR_MINOR_BASE);
+ return retval;
+
+error:
+ iowarrior_delete(dev);
+ return retval;
+}
+
+/*
+ * iowarrior_disconnect
+ *
+ * Called by the usb core when the device is removed from the system.
+ */
+static void iowarrior_disconnect(struct usb_interface *interface)
+{
+ struct iowarrior *dev = usb_get_intfdata(interface);
+ int minor = dev->minor;
+
+ usb_deregister_dev(interface, &iowarrior_class);
+
+ mutex_lock(&dev->mutex);
+
+ /* prevent device read, write and ioctl */
+ dev->present = 0;
+
+ if (dev->opened) {
+ /* There is a process that holds a filedescriptor to the device ,
+ so we only shutdown read-/write-ops going on.
+ Deleting the device is postponed until close() was called.
+ */
+ usb_kill_urb(dev->int_in_urb);
+ usb_kill_anchored_urbs(&dev->submitted);
+ wake_up_interruptible(&dev->read_wait);
+ wake_up_interruptible(&dev->write_wait);
+ mutex_unlock(&dev->mutex);
+ } else {
+ /* no process is using the device, cleanup now */
+ mutex_unlock(&dev->mutex);
+ iowarrior_delete(dev);
+ }
+
+ dev_info(&interface->dev, "I/O-Warror #%d now disconnected\n",
+ minor - IOWARRIOR_MINOR_BASE);
+}
+
+/* usb specific object needed to register this driver with the usb subsystem */
+static struct usb_driver iowarrior_driver = {
+ .name = "iowarrior",
+ .probe = iowarrior_probe,
+ .disconnect = iowarrior_disconnect,
+ .id_table = iowarrior_ids,
+};
+
+module_usb_driver(iowarrior_driver);