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|
/*
module/drivers.c
functions for manipulating drivers
COMEDI - Linux Control and Measurement Device Interface
Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
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.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#define _GNU_SOURCE
#define __NO_VERSION__
#include "comedi_fops.h"
#include <linux/device.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/usb.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fcntl.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include "comedidev.h"
#include "wrapper.h"
#include <linux/highmem.h> /* for SuSE brokenness */
#include <linux/vmalloc.h>
#include <linux/cdev.h>
#include <linux/dma-mapping.h>
#include <asm/io.h>
#include <asm/system.h>
static int postconfig(struct comedi_device *dev);
static int insn_rw_emulate_bits(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data);
static void *comedi_recognize(struct comedi_driver *driv, const char *name);
static void comedi_report_boards(struct comedi_driver *driv);
static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s);
int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s,
unsigned long new_size);
struct comedi_driver *comedi_drivers;
int comedi_modprobe(int minor)
{
return -EINVAL;
}
static void cleanup_device(struct comedi_device *dev)
{
int i;
struct comedi_subdevice *s;
if (dev->subdevices) {
for (i = 0; i < dev->n_subdevices; i++) {
s = dev->subdevices + i;
comedi_free_subdevice_minor(s);
if (s->async) {
comedi_buf_alloc(dev, s, 0);
kfree(s->async);
}
}
kfree(dev->subdevices);
dev->subdevices = NULL;
dev->n_subdevices = 0;
}
kfree(dev->private);
dev->private = NULL;
dev->driver = 0;
dev->board_name = NULL;
dev->board_ptr = NULL;
dev->iobase = 0;
dev->irq = 0;
dev->read_subdev = NULL;
dev->write_subdev = NULL;
dev->open = NULL;
dev->close = NULL;
comedi_set_hw_dev(dev, NULL);
}
static void __comedi_device_detach(struct comedi_device *dev)
{
dev->attached = 0;
if (dev->driver) {
dev->driver->detach(dev);
} else {
printk("BUG: dev->driver=NULL in comedi_device_detach()\n");
}
cleanup_device(dev);
}
void comedi_device_detach(struct comedi_device *dev)
{
if (!dev->attached)
return;
__comedi_device_detach(dev);
}
int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
struct comedi_driver *driv;
int ret;
if (dev->attached)
return -EBUSY;
for (driv = comedi_drivers; driv; driv = driv->next) {
if (!try_module_get(driv->module)) {
printk
("comedi: failed to increment module count, skipping\n");
continue;
}
if (driv->num_names) {
dev->board_ptr = comedi_recognize(driv, it->board_name);
if (dev->board_ptr == NULL) {
module_put(driv->module);
continue;
}
} else {
if (strcmp(driv->driver_name, it->board_name)) {
module_put(driv->module);
continue;
}
}
/* initialize dev->driver here so comedi_error() can be called from attach */
dev->driver = driv;
ret = driv->attach(dev, it);
if (ret < 0) {
module_put(dev->driver->module);
__comedi_device_detach(dev);
return ret;
}
goto attached;
}
/* recognize has failed if we get here */
/* report valid board names before returning error */
for (driv = comedi_drivers; driv; driv = driv->next) {
if (!try_module_get(driv->module)) {
printk("comedi: failed to increment module count\n");
continue;
}
comedi_report_boards(driv);
module_put(driv->module);
}
return -EIO;
attached:
/* do a little post-config cleanup */
ret = postconfig(dev);
module_put(dev->driver->module);
if (ret < 0) {
__comedi_device_detach(dev);
return ret;
}
if (!dev->board_name) {
printk("BUG: dev->board_name=<%p>\n", dev->board_name);
dev->board_name = "BUG";
}
smp_wmb();
dev->attached = 1;
return 0;
}
int comedi_driver_register(struct comedi_driver *driver)
{
driver->next = comedi_drivers;
comedi_drivers = driver;
return 0;
}
int comedi_driver_unregister(struct comedi_driver *driver)
{
struct comedi_driver *prev;
int i;
/* check for devices using this driver */
for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
struct comedi_device_file_info *dev_file_info =
comedi_get_device_file_info(i);
struct comedi_device *dev;
if (dev_file_info == NULL)
continue;
dev = dev_file_info->device;
mutex_lock(&dev->mutex);
if (dev->attached && dev->driver == driver) {
if (dev->use_count)
printk
("BUG! detaching device with use_count=%d\n",
dev->use_count);
comedi_device_detach(dev);
}
mutex_unlock(&dev->mutex);
}
if (comedi_drivers == driver) {
comedi_drivers = driver->next;
return 0;
}
for (prev = comedi_drivers; prev->next; prev = prev->next) {
if (prev->next == driver) {
prev->next = driver->next;
return 0;
}
}
return -EINVAL;
}
static int postconfig(struct comedi_device *dev)
{
int i;
struct comedi_subdevice *s;
struct comedi_async *async = NULL;
int ret;
for (i = 0; i < dev->n_subdevices; i++) {
s = dev->subdevices + i;
if (s->type == COMEDI_SUBD_UNUSED)
continue;
if (s->len_chanlist == 0)
s->len_chanlist = 1;
if (s->do_cmd) {
BUG_ON((s->subdev_flags & (SDF_CMD_READ |
SDF_CMD_WRITE)) == 0);
BUG_ON(!s->do_cmdtest);
async =
kzalloc(sizeof(struct comedi_async), GFP_KERNEL);
if (async == NULL) {
printk("failed to allocate async struct\n");
return -ENOMEM;
}
init_waitqueue_head(&async->wait_head);
async->subdevice = s;
s->async = async;
#define DEFAULT_BUF_MAXSIZE (64*1024)
#define DEFAULT_BUF_SIZE (64*1024)
async->max_bufsize = DEFAULT_BUF_MAXSIZE;
async->prealloc_buf = NULL;
async->prealloc_bufsz = 0;
if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) {
printk("Buffer allocation failed\n");
return -ENOMEM;
}
if (s->buf_change) {
ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE);
if (ret < 0)
return ret;
}
comedi_alloc_subdevice_minor(dev, s);
}
if (!s->range_table && !s->range_table_list)
s->range_table = &range_unknown;
if (!s->insn_read && s->insn_bits)
s->insn_read = insn_rw_emulate_bits;
if (!s->insn_write && s->insn_bits)
s->insn_write = insn_rw_emulate_bits;
if (!s->insn_read)
s->insn_read = insn_inval;
if (!s->insn_write)
s->insn_write = insn_inval;
if (!s->insn_bits)
s->insn_bits = insn_inval;
if (!s->insn_config)
s->insn_config = insn_inval;
if (!s->poll)
s->poll = poll_invalid;
}
return 0;
}
/* generic recognize function for drivers that register their supported board names */
void *comedi_recognize(struct comedi_driver *driv, const char *name)
{
unsigned i;
const char *const *name_ptr = driv->board_name;
for (i = 0; i < driv->num_names; i++) {
if (strcmp(*name_ptr, name) == 0)
return (void *)name_ptr;
name_ptr =
(const char *const *)((const char *)name_ptr +
driv->offset);
}
return NULL;
}
void comedi_report_boards(struct comedi_driver *driv)
{
unsigned int i;
const char *const *name_ptr;
printk("comedi: valid board names for %s driver are:\n",
driv->driver_name);
name_ptr = driv->board_name;
for (i = 0; i < driv->num_names; i++) {
printk(" %s\n", *name_ptr);
name_ptr = (const char **)((char *)name_ptr + driv->offset);
}
if (driv->num_names == 0)
printk(" %s\n", driv->driver_name);
}
static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
{
return -EINVAL;
}
int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data)
{
return -EINVAL;
}
static int insn_rw_emulate_bits(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data)
{
struct comedi_insn new_insn;
int ret;
static const unsigned channels_per_bitfield = 32;
unsigned chan = CR_CHAN(insn->chanspec);
const unsigned base_bitfield_channel =
(chan < channels_per_bitfield) ? 0 : chan;
unsigned int new_data[2];
memset(new_data, 0, sizeof(new_data));
memset(&new_insn, 0, sizeof(new_insn));
new_insn.insn = INSN_BITS;
new_insn.chanspec = base_bitfield_channel;
new_insn.n = 2;
new_insn.data = new_data;
new_insn.subdev = insn->subdev;
if (insn->insn == INSN_WRITE) {
if (!(s->subdev_flags & SDF_WRITABLE))
return -EINVAL;
new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */
new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) : 0; /* bits */
}
ret = s->insn_bits(dev, s, &new_insn, new_data);
if (ret < 0)
return ret;
if (insn->insn == INSN_READ) {
data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1;
}
return 1;
}
static inline unsigned long uvirt_to_kva(pgd_t * pgd, unsigned long adr)
{
unsigned long ret = 0UL;
pmd_t *pmd;
pte_t *ptep, pte;
pud_t *pud;
if (!pgd_none(*pgd)) {
pud = pud_offset(pgd, adr);
pmd = pmd_offset(pud, adr);
if (!pmd_none(*pmd)) {
ptep = pte_offset_kernel(pmd, adr);
pte = *ptep;
if (pte_present(pte)) {
ret = (unsigned long)
page_address(pte_page(pte));
ret |= (adr & (PAGE_SIZE - 1));
}
}
}
return ret;
}
static inline unsigned long kvirt_to_kva(unsigned long adr)
{
unsigned long va, kva;
va = adr;
kva = uvirt_to_kva(pgd_offset_k(va), va);
return kva;
}
int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s,
unsigned long new_size)
{
struct comedi_async *async = s->async;
/* Round up new_size to multiple of PAGE_SIZE */
new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK;
/* if no change is required, do nothing */
if (async->prealloc_buf && async->prealloc_bufsz == new_size) {
return 0;
}
/* deallocate old buffer */
if (async->prealloc_buf) {
vunmap(async->prealloc_buf);
async->prealloc_buf = NULL;
async->prealloc_bufsz = 0;
}
if (async->buf_page_list) {
unsigned i;
for (i = 0; i < async->n_buf_pages; ++i) {
if (async->buf_page_list[i].virt_addr) {
mem_map_unreserve(virt_to_page
(async->buf_page_list[i].
virt_addr));
if (s->async_dma_dir != DMA_NONE) {
dma_free_coherent(dev->hw_dev,
PAGE_SIZE,
async->
buf_page_list
[i].virt_addr,
async->
buf_page_list
[i].dma_addr);
} else {
free_page((unsigned long)
async->buf_page_list[i].
virt_addr);
}
}
}
vfree(async->buf_page_list);
async->buf_page_list = NULL;
async->n_buf_pages = 0;
}
/* allocate new buffer */
if (new_size) {
unsigned i = 0;
unsigned n_pages = new_size >> PAGE_SHIFT;
struct page **pages = NULL;
async->buf_page_list =
vmalloc(sizeof(struct comedi_buf_page) * n_pages);
if (async->buf_page_list) {
memset(async->buf_page_list, 0,
sizeof(struct comedi_buf_page) * n_pages);
pages = vmalloc(sizeof(struct page *) * n_pages);
}
if (pages) {
for (i = 0; i < n_pages; i++) {
if (s->async_dma_dir != DMA_NONE) {
async->buf_page_list[i].virt_addr =
dma_alloc_coherent(dev->hw_dev,
PAGE_SIZE,
&async->
buf_page_list
[i].dma_addr,
GFP_KERNEL |
__GFP_COMP);
} else {
async->buf_page_list[i].virt_addr =
(void *)
get_zeroed_page(GFP_KERNEL);
}
if (async->buf_page_list[i].virt_addr == NULL) {
break;
}
mem_map_reserve(virt_to_page
(async->buf_page_list[i].
virt_addr));
pages[i] =
virt_to_page(async->
buf_page_list[i].virt_addr);
}
}
if (i == n_pages) {
async->prealloc_buf =
vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE);
}
if (pages) {
vfree(pages);
}
if (async->prealloc_buf == NULL) {
/* Some allocation failed above. */
if (async->buf_page_list) {
for (i = 0; i < n_pages; i++) {
if (async->buf_page_list[i].virt_addr ==
NULL) {
break;
}
mem_map_unreserve(virt_to_page
(async->buf_page_list
[i].virt_addr));
if (s->async_dma_dir != DMA_NONE) {
dma_free_coherent(dev->hw_dev,
PAGE_SIZE,
async->
buf_page_list
[i].virt_addr,
async->
buf_page_list
[i].dma_addr);
} else {
free_page((unsigned long)
async->buf_page_list
[i].virt_addr);
}
}
vfree(async->buf_page_list);
async->buf_page_list = NULL;
}
return -ENOMEM;
}
async->n_buf_pages = n_pages;
}
async->prealloc_bufsz = new_size;
return 0;
}
/* munging is applied to data by core as it passes between user
* and kernel space */
unsigned int comedi_buf_munge(struct comedi_async *async,
unsigned int num_bytes)
{
struct comedi_subdevice *s = async->subdevice;
unsigned int count = 0;
const unsigned num_sample_bytes = bytes_per_sample(s);
if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) {
async->munge_count += num_bytes;
BUG_ON((int)(async->munge_count - async->buf_write_count) > 0);
return num_bytes;
}
/* don't munge partial samples */
num_bytes -= num_bytes % num_sample_bytes;
while (count < num_bytes) {
int block_size;
block_size = num_bytes - count;
if (block_size < 0) {
printk("%s: %s: bug! block_size is negative\n",
__FILE__, __func__);
break;
}
if ((int)(async->munge_ptr + block_size -
async->prealloc_bufsz) > 0)
block_size = async->prealloc_bufsz - async->munge_ptr;
s->munge(s->device, s, async->prealloc_buf + async->munge_ptr,
block_size, async->munge_chan);
smp_wmb(); /* barrier insures data is munged in buffer before munge_count is incremented */
async->munge_chan += block_size / num_sample_bytes;
async->munge_chan %= async->cmd.chanlist_len;
async->munge_count += block_size;
async->munge_ptr += block_size;
async->munge_ptr %= async->prealloc_bufsz;
count += block_size;
}
BUG_ON((int)(async->munge_count - async->buf_write_count) > 0);
return count;
}
unsigned int comedi_buf_write_n_available(struct comedi_async *async)
{
unsigned int free_end;
unsigned int nbytes;
if (async == NULL)
return 0;
free_end = async->buf_read_count + async->prealloc_bufsz;
nbytes = free_end - async->buf_write_alloc_count;
nbytes -= nbytes % bytes_per_sample(async->subdevice);
/* barrier insures the read of buf_read_count in this
query occurs before any following writes to the buffer which
might be based on the return value from this query.
*/
smp_mb();
return nbytes;
}
/* allocates chunk for the writer from free buffer space */
unsigned int comedi_buf_write_alloc(struct comedi_async *async,
unsigned int nbytes)
{
unsigned int free_end = async->buf_read_count + async->prealloc_bufsz;
if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) {
nbytes = free_end - async->buf_write_alloc_count;
}
async->buf_write_alloc_count += nbytes;
/* barrier insures the read of buf_read_count above occurs before
we write data to the write-alloc'ed buffer space */
smp_mb();
return nbytes;
}
/* allocates nothing unless it can completely fulfill the request */
unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async,
unsigned int nbytes)
{
unsigned int free_end = async->buf_read_count + async->prealloc_bufsz;
if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) {
nbytes = 0;
}
async->buf_write_alloc_count += nbytes;
/* barrier insures the read of buf_read_count above occurs before
we write data to the write-alloc'ed buffer space */
smp_mb();
return nbytes;
}
/* transfers a chunk from writer to filled buffer space */
unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes)
{
if ((int)(async->buf_write_count + nbytes -
async->buf_write_alloc_count) > 0) {
printk
("comedi: attempted to write-free more bytes than have been write-allocated.\n");
nbytes = async->buf_write_alloc_count - async->buf_write_count;
}
async->buf_write_count += nbytes;
async->buf_write_ptr += nbytes;
comedi_buf_munge(async, async->buf_write_count - async->munge_count);
if (async->buf_write_ptr >= async->prealloc_bufsz) {
async->buf_write_ptr %= async->prealloc_bufsz;
}
return nbytes;
}
/* allocates a chunk for the reader from filled (and munged) buffer space */
unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes)
{
if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) >
0) {
nbytes = async->munge_count - async->buf_read_alloc_count;
}
async->buf_read_alloc_count += nbytes;
/* barrier insures read of munge_count occurs before we actually read
data out of buffer */
smp_rmb();
return nbytes;
}
/* transfers control of a chunk from reader to free buffer space */
unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes)
{
/* barrier insures data has been read out of buffer before read count is incremented */
smp_mb();
if ((int)(async->buf_read_count + nbytes -
async->buf_read_alloc_count) > 0) {
printk
("comedi: attempted to read-free more bytes than have been read-allocated.\n");
nbytes = async->buf_read_alloc_count - async->buf_read_count;
}
async->buf_read_count += nbytes;
async->buf_read_ptr += nbytes;
async->buf_read_ptr %= async->prealloc_bufsz;
return nbytes;
}
void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset,
const void *data, unsigned int num_bytes)
{
unsigned int write_ptr = async->buf_write_ptr + offset;
if (write_ptr >= async->prealloc_bufsz)
write_ptr %= async->prealloc_bufsz;
while (num_bytes) {
unsigned int block_size;
if (write_ptr + num_bytes > async->prealloc_bufsz)
block_size = async->prealloc_bufsz - write_ptr;
else
block_size = num_bytes;
memcpy(async->prealloc_buf + write_ptr, data, block_size);
data += block_size;
num_bytes -= block_size;
write_ptr = 0;
}
}
void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset,
void *dest, unsigned int nbytes)
{
void *src;
unsigned int read_ptr = async->buf_read_ptr + offset;
if (read_ptr >= async->prealloc_bufsz)
read_ptr %= async->prealloc_bufsz;
while (nbytes) {
unsigned int block_size;
src = async->prealloc_buf + read_ptr;
if (nbytes >= async->prealloc_bufsz - read_ptr)
block_size = async->prealloc_bufsz - read_ptr;
else
block_size = nbytes;
memcpy(dest, src, block_size);
nbytes -= block_size;
dest += block_size;
read_ptr = 0;
}
}
unsigned int comedi_buf_read_n_available(struct comedi_async *async)
{
unsigned num_bytes;
if (async == NULL)
return 0;
num_bytes = async->munge_count - async->buf_read_count;
/* barrier insures the read of munge_count in this
query occurs before any following reads of the buffer which
might be based on the return value from this query.
*/
smp_rmb();
return num_bytes;
}
int comedi_buf_get(struct comedi_async *async, short *x)
{
unsigned int n = comedi_buf_read_n_available(async);
if (n < sizeof(short))
return 0;
comedi_buf_read_alloc(async, sizeof(short));
*x = *(short *)(async->prealloc_buf + async->buf_read_ptr);
comedi_buf_read_free(async, sizeof(short));
return 1;
}
int comedi_buf_put(struct comedi_async *async, short x)
{
unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short));
if (n < sizeof(short)) {
async->events |= COMEDI_CB_ERROR;
return 0;
}
*(short *)(async->prealloc_buf + async->buf_write_ptr) = x;
comedi_buf_write_free(async, sizeof(short));
return 1;
}
void comedi_reset_async_buf(struct comedi_async *async)
{
async->buf_write_alloc_count = 0;
async->buf_write_count = 0;
async->buf_read_alloc_count = 0;
async->buf_read_count = 0;
async->buf_write_ptr = 0;
async->buf_read_ptr = 0;
async->cur_chan = 0;
async->scan_progress = 0;
async->munge_chan = 0;
async->munge_count = 0;
async->munge_ptr = 0;
async->events = 0;
}
int comedi_auto_config(struct device *hardware_device, const char *board_name,
const int *options, unsigned num_options)
{
struct comedi_devconfig it;
int minor;
struct comedi_device_file_info *dev_file_info;
int retval;
unsigned *private_data = NULL;
if (!comedi_autoconfig) {
dev_set_drvdata(hardware_device, NULL);
return 0;
}
minor = comedi_alloc_board_minor(hardware_device);
if (minor < 0)
return minor;
private_data = kmalloc(sizeof(unsigned), GFP_KERNEL);
if (private_data == NULL) {
retval = -ENOMEM;
goto cleanup;
}
*private_data = minor;
dev_set_drvdata(hardware_device, private_data);
dev_file_info = comedi_get_device_file_info(minor);
memset(&it, 0, sizeof(it));
strncpy(it.board_name, board_name, COMEDI_NAMELEN);
it.board_name[COMEDI_NAMELEN - 1] = '\0';
BUG_ON(num_options > COMEDI_NDEVCONFOPTS);
memcpy(it.options, options, num_options * sizeof(int));
mutex_lock(&dev_file_info->device->mutex);
retval = comedi_device_attach(dev_file_info->device, &it);
mutex_unlock(&dev_file_info->device->mutex);
cleanup:
if (retval < 0) {
kfree(private_data);
comedi_free_board_minor(minor);
}
return retval;
}
void comedi_auto_unconfig(struct device *hardware_device)
{
unsigned *minor = (unsigned *)dev_get_drvdata(hardware_device);
if (minor == NULL)
return;
BUG_ON(*minor >= COMEDI_NUM_BOARD_MINORS);
comedi_free_board_minor(*minor);
dev_set_drvdata(hardware_device, NULL);
kfree(minor);
}
int comedi_pci_auto_config(struct pci_dev *pcidev, const char *board_name)
{
int options[2];
/* pci bus */
options[0] = pcidev->bus->number;
/* pci slot */
options[1] = PCI_SLOT(pcidev->devfn);
return comedi_auto_config(&pcidev->dev, board_name,
options, ARRAY_SIZE(options));
}
void comedi_pci_auto_unconfig(struct pci_dev *pcidev)
{
comedi_auto_unconfig(&pcidev->dev);
}
int comedi_usb_auto_config(struct usb_device *usbdev, const char *board_name)
{
BUG_ON(usbdev == NULL);
return comedi_auto_config(&usbdev->dev, board_name, NULL, 0);
}
void comedi_usb_auto_unconfig(struct usb_device *usbdev)
{
BUG_ON(usbdev == NULL);
comedi_auto_unconfig(&usbdev->dev);
}
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