// SPDX-License-Identifier: GPL-2.0+
/*
* 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 <[email protected]>
*
* Derived from Lego USB Tower driver
* Copyright (C) 2003 David Glance <[email protected]>
* 2001-2004 Juergen Stuber <[email protected]>
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/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_LD_CASSY 0x1000 /* USB Product ID of CASSY-S modules with 8 bytes endpoint size */
#define USB_DEVICE_ID_LD_CASSY2 0x1001 /* USB Product ID of CASSY-S modules with 64 bytes endpoint size */
#define USB_DEVICE_ID_LD_POCKETCASSY 0x1010 /* USB Product ID of Pocket-CASSY */
#define USB_DEVICE_ID_LD_POCKETCASSY2 0x1011 /* USB Product ID of Pocket-CASSY 2 (reserved) */
#define USB_DEVICE_ID_LD_MOBILECASSY 0x1020 /* USB Product ID of Mobile-CASSY */
#define USB_DEVICE_ID_LD_MOBILECASSY2 0x1021 /* USB Product ID of Mobile-CASSY 2 (reserved) */
#define USB_DEVICE_ID_LD_MICROCASSYVOLTAGE 0x1031 /* USB Product ID of Micro-CASSY Voltage */
#define USB_DEVICE_ID_LD_MICROCASSYCURRENT 0x1032 /* USB Product ID of Micro-CASSY Current */
#define USB_DEVICE_ID_LD_MICROCASSYTIME 0x1033 /* USB Product ID of Micro-CASSY Time (reserved) */
#define USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE 0x1035 /* USB Product ID of Micro-CASSY Temperature */
#define USB_DEVICE_ID_LD_MICROCASSYPH 0x1038 /* USB Product ID of Micro-CASSY pH */
#define USB_DEVICE_ID_LD_POWERANALYSERCASSY 0x1040 /* USB Product ID of Power Analyser CASSY */
#define USB_DEVICE_ID_LD_CONVERTERCONTROLLERCASSY 0x1042 /* USB Product ID of Converter Controller CASSY */
#define USB_DEVICE_ID_LD_MACHINETESTCASSY 0x1043 /* USB Product ID of Machine Test CASSY */
#define USB_DEVICE_ID_LD_JWM 0x1080 /* USB Product ID of Joule and Wattmeter */
#define USB_DEVICE_ID_LD_DMMP 0x1081 /* USB Product ID of Digital Multimeter P (reserved) */
#define USB_DEVICE_ID_LD_UMIP 0x1090 /* USB Product ID of UMI P */
#define USB_DEVICE_ID_LD_UMIC 0x10A0 /* USB Product ID of UMI C */
#define USB_DEVICE_ID_LD_UMIB 0x10B0 /* USB Product ID of UMI B */
#define USB_DEVICE_ID_LD_XRAY 0x1100 /* USB Product ID of X-Ray Apparatus 55481 */
#define USB_DEVICE_ID_LD_XRAY2 0x1101 /* USB Product ID of X-Ray Apparatus 554800 */
#define USB_DEVICE_ID_LD_XRAYCT 0x1110 /* USB Product ID of X-Ray Apparatus CT 554821*/
#define USB_DEVICE_ID_LD_VIDEOCOM 0x1200 /* USB Product ID of VideoCom */
#define USB_DEVICE_ID_LD_MOTOR 0x1210 /* USB Product ID of Motor (reserved) */
#define USB_DEVICE_ID_LD_COM3LAB 0x2000 /* USB Product ID of COM3LAB */
#define USB_DEVICE_ID_LD_TELEPORT 0x2010 /* USB Product ID of Terminal Adapter */
#define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */
#define USB_DEVICE_ID_LD_POWERCONTROL 0x2030 /* USB Product ID of Converter Control Unit */
#define USB_DEVICE_ID_LD_MACHINETEST 0x2040 /* USB Product ID of Machine Test System */
#define USB_DEVICE_ID_LD_MOSTANALYSER 0x2050 /* USB Product ID of MOST Protocol Analyser */
#define USB_DEVICE_ID_LD_MOSTANALYSER2 0x2051 /* USB Product ID of MOST Protocol Analyser 2 */
#define USB_DEVICE_ID_LD_ABSESP 0x2060 /* USB Product ID of ABS ESP */
#define USB_DEVICE_ID_LD_AUTODATABUS 0x2070 /* USB Product ID of Automotive Data Buses */
#define USB_DEVICE_ID_LD_MCT 0x2080 /* USB Product ID of Microcontroller technique */
#define USB_DEVICE_ID_LD_HYBRID 0x2090 /* USB Product ID of Automotive Hybrid */
#define USB_DEVICE_ID_LD_HEATCONTROL 0x20A0 /* USB Product ID of Heat control */
#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 const struct usb_device_id ld_usb_table[] = {
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY2) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY2) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY2) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYVOLTAGE) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYCURRENT) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTIME) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYPH) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERANALYSERCASSY) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CONVERTERCONTROLLERCASSY) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETESTCASSY) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIC) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIB) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOTOR) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER2) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_ABSESP) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_AUTODATABUS) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MCT) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HYBRID) },
{ USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HEATCONTROL) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, ld_usb_table);
MODULE_AUTHOR("Michael Hund <[email protected]>");
MODULE_DESCRIPTION("LD USB Driver");
MODULE_LICENSE("GPL");
/* 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, 0000);
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, 0000);
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, 0000);
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, 0000);
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 mutex mutex; /* locks this structure */
struct usb_interface *intf; /* save off the usb interface pointer */
unsigned long disconnected:1;
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;
int buffer_overflow;
spinlock_t rbsl;
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;
};
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;
usb_kill_urb(dev->interrupt_in_urb);
}
if (dev->interrupt_out_busy)
usb_kill_urb(dev->interrupt_out_urb);
}
/*
* ld_usb_delete
*/
static void ld_usb_delete(struct ld_usb *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 ld_usb *dev = urb->context;
size_t *actual_buffer;
unsigned int next_ring_head;
int status = urb->status;
unsigned long flags;
int retval;
if (status) {
if (status == -ENOENT ||
status == -ECONNRESET ||
status == -ESHUTDOWN) {
goto exit;
} else {
dev_dbg(&dev->intf->dev,
"%s: nonzero status received: %d\n", __func__,
status);
spin_lock_irqsave(&dev->rbsl, flags);
goto resubmit; /* maybe we can recover */
}
}
spin_lock_irqsave(&dev->rbsl, flags);
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;
dev_dbg(&dev->intf->dev, "%s: received %d bytes\n",
__func__, urb->actual_length);
} else {
dev_warn(&dev->intf->dev,
"Ring buffer overflow, %d bytes dropped\n",
urb->actual_length);
dev->buffer_overflow = 1;
}
}
resubmit:
/* resubmit if we're still running */
if (dev->interrupt_in_running && !dev->buffer_overflow) {
retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
if (retval) {
dev_err(&dev->intf->dev,
"usb_submit_urb failed (%d)\n", retval);
dev->buffer_overflow = 1;
}
}
spin_unlock_irqrestore(&dev->rbsl, flags);
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 ld_usb *dev = urb->context;
int status = urb->status;
/* sync/async unlink faults aren't errors */
if (status && !(status == -ENOENT ||
status == -ECONNRESET ||
status == -ESHUTDOWN))
dev_dbg(&dev->intf->dev,
"%s - nonzero write interrupt status received: %d\n",
__func__, 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;
struct usb_interface *interface;
stream_open(inode, file);
subminor = iminor(inode);
interface = usb_find_interface(&ld_usb_driver, subminor);
if (!interface) {
printk(KERN_ERR "%s - error, can't find device for minor %d\n",
__func__, subminor);
return -ENODEV;
}
dev = usb_get_intfdata(interface);
if (!dev)
return -ENODEV;
/* lock this device */
if (mutex_lock_interruptible(&dev->mutex))
return -ERESTARTSYS;
/* 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;
dev->buffer_overflow = 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:
mutex_unlock(&dev->mutex);
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;
}
mutex_lock(&dev->mutex);
if (dev->open_count != 1) {
retval = -ENODEV;
goto unlock_exit;
}
if (dev->disconnected) {
/* the device was unplugged before the file was released */
mutex_unlock(&dev->mutex);
/* 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:
mutex_unlock(&dev->mutex);
exit:
return retval;
}
/*
* ld_usb_poll
*/
static __poll_t ld_usb_poll(struct file *file, poll_table *wait)
{
struct ld_usb *dev;
__poll_t mask = 0;
dev = file->private_data;
if (dev->disconnected)
return EPOLLERR | EPOLLHUP;
poll_wait(file, &dev->read_wait, wait);
poll_wait(file, &dev->write_wait, wait);
if (dev->ring_head != dev->ring_tail)
mask |= EPOLLIN | EPOLLRDNORM;
if (!dev->interrupt_out_busy)
mask |= EPOLLOUT | EPOLLWRNORM;
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;
int rv;
dev = file->private_data;
/* verify that we actually have some data to read */
if (count == 0)
goto exit;
/* lock this object */
if (mutex_lock_interruptible(&dev->mutex)) {
retval = -ERESTARTSYS;
goto exit;
}
/* verify that the device wasn't unplugged */
if (dev->disconnected) {
retval = -ENODEV;
printk(KERN_ERR "ldusb: No device or device unplugged %d\n", retval);
goto unlock_exit;
}
/* wait for data */
spin_lock_irq(&dev->rbsl);
while (dev->ring_head == dev->ring_tail) {
dev->interrupt_in_done = 0;
spin_unlock_irq(&dev->rbsl);
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;
spin_lock_irq(&dev->rbsl);
}
spin_unlock_irq(&dev->rbsl);
/* 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));
if (*actual_buffer > dev->interrupt_in_endpoint_size) {
retval = -EIO;
goto unlock_exit;
}
bytes_to_read = min(count, *actual_buffer);
if (bytes_to_read < *actual_buffer)
dev_warn(&dev->intf->dev, "Read buffer overflow, %zu 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;
}
retval = bytes_to_read;
spin_lock_irq(&dev->rbsl);
dev->ring_tail = (dev->ring_tail + 1) % ring_buffer_size;
if (dev->buffer_overflow) {
dev->buffer_overflow = 0;
spin_unlock_irq(&dev->rbsl);
rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
if (rv < 0)
dev->buffer_overflow = 1;
} else {
spin_unlock_irq(&dev->rbsl);
}
unlock_exit:
/* unlock the device */
mutex_unlock(&dev->mutex);
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 (mutex_lock_interruptible(&dev->mutex)) {
retval = -ERESTARTSYS;
goto exit;
}
/* verify that the device wasn't unplugged */
if (dev->disconnected) {
retval = -ENODEV;
printk(KERN_ERR "ldusb: 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, %zu bytes dropped\n",
count - bytes_to_write);
dev_dbg(&dev->intf->dev, "%s: count = %zu, bytes_to_write = %zu\n",
__func__, count, bytes_to_write);
if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
retval = -EFAULT;
goto unlock_exit;
}
if (dev->interrupt_out_endpoint == NULL) {
/* 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);
if (retval < 0)
dev_err(&dev->intf->dev,
"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;
dev_err(&dev->intf->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->mutex);
exit:
return retval;
}
/* file operations needed when we register this driver */
static const 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 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;
char *buffer;
int retval = -ENOMEM;
int res;
/* allocate memory for our device state and initialize it */
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
goto exit;
mutex_init(&dev->mutex);
spin_lock_init(&dev->rbsl);
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_LD_CASSY) ||
(le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
(le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
buffer = kmalloc(256, GFP_KERNEL);
if (!buffer)
goto error;
/* usb_string makes SETUP+STALL to leave always ControlReadLoop */
usb_string(udev, 255, buffer, 256);
kfree(buffer);
}
iface_desc = intf->cur_altsetting;
res = usb_find_last_int_in_endpoint(iface_desc,
&dev->interrupt_in_endpoint);
if (res) {
dev_err(&intf->dev, "Interrupt in endpoint not found\n");
retval = res;
goto error;
}
res = usb_find_last_int_out_endpoint(iface_desc,
&dev->interrupt_out_endpoint);
if (res)
dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint);
dev->ring_buffer = kcalloc(ring_buffer_size,
sizeof(size_t) + dev->interrupt_in_endpoint_size,
GFP_KERNEL);
if (!dev->ring_buffer)
goto error;
dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
if (!dev->interrupt_in_buffer)
goto error;
dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->interrupt_in_urb)
goto error;
dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) :
udev->descriptor.bMaxPacketSize0;
dev->interrupt_out_buffer =
kmalloc_array(write_buffer_size,
dev->interrupt_out_endpoint_size, GFP_KERNEL);
if (!dev->interrupt_out_buffer)
goto error;
dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->interrupt_out_urb)
goto error;
dev->interrupt_in_interval = max_t(int, min_interrupt_in_interval,
dev->interrupt_in_endpoint->bInterval);
if (dev->interrupt_out_endpoint)
dev->interrupt_out_interval = max_t(int, 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;
dev = usb_get_intfdata(intf);
usb_set_intfdata(intf, NULL);
minor = intf->minor;
/* give back our minor */
usb_deregister_dev(intf, &ld_usb_class);
usb_poison_urb(dev->interrupt_in_urb);
usb_poison_urb(dev->interrupt_out_urb);
mutex_lock(&dev->mutex);
/* if the device is not opened, then we clean up right now */
if (!dev->open_count) {
mutex_unlock(&dev->mutex);
ld_usb_delete(dev);
} else {
dev->disconnected = 1;
/* wake up pollers */
wake_up_interruptible_all(&dev->read_wait);
wake_up_interruptible_all(&dev->write_wait);
mutex_unlock(&dev->mutex);
}
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 = {
.name = "ldusb",
.probe = ld_usb_probe,
.disconnect = ld_usb_disconnect,
.id_table = ld_usb_table,
};
module_usb_driver(ld_usb_driver);
Codebase Browser
linux