![Bob Ham](/assets/img/avatar_default.png)
The first read on an Alea takes about 1.8 seconds, more than the timeout value waiting for the read. As a consequence, later URB reuse causes the warning given below. To avoid this, we increase the wait time for the first read on the Alea. [ 78.293247] WARNING: CPU: 3 PID: 1892 at drivers/usb/core/urb.c:338 usb_submit_urb+0x2b4/0x580 [usbcore] [ 78.293250] URB ffff8802135be3c0 submitted while active [ 78.293252] Modules linked in: chaoskey(+) rng_core rfcomm binfmt_misc bnep cfg80211 nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc bridge stp llc tun snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic iTCO_wdt iTCO_vendor_support nls_utf8 nls_cp437 vfat fat intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel efi_pstore kvm irqbypass pcspkr btusb btrtl btbcm btintel uvcvideo joydev bluetooth videobuf2_vmalloc videobuf2_memops efivars videobuf2_v4l2 serio_raw i2c_i801 videobuf2_core videodev cdc_mbim media lpc_ich shpchp mfd_core cdc_ncm usbnet mii cdc_wdm cdc_acm evdev snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core i915 snd_pcm snd_timer i2c_algo_bit drm_kms_helper wmi thinkpad_acpi drm nvram mei_me mei snd soundcore rfkill ac battery i2c_core [ 78.293335] video button tpm_tis tpm fuse parport_pc ppdev lp parport autofs4 ext4 crc16 jbd2 mbcache algif_skcipher af_alg hid_generic usbhid hid dm_crypt dm_mod sg sr_mod cdrom sd_mod crct10dif_pclmul crc32_pclmul crc32c_intel jitterentropy_rng sha256_generic hmac drbg aesni_intel xhci_pci aes_x86_64 ahci glue_helper xhci_hcd ehci_pci lrw libahci gf128mul ablk_helper cryptd libata sdhci_pci psmouse sdhci scsi_mod ehci_hcd mmc_core usbcore usb_common thermal [ 78.293402] CPU: 3 PID: 1892 Comm: hwrng Not tainted 4.7.0-rc1-linux-14+ #16 [ 78.293405] Hardware name: LENOVO 232577G/232577G, BIOS G2ET92WW (2.52 ) 02/22/2013 [ 78.293408] 0000000000000000 ffffffff812dfa0f ffff8801fa5b3d68 0000000000000000 [ 78.293413] ffffffff81072224 ffff8802135be3c0 ffff8801fa5b3db8 ffff880212e44210 [ 78.293418] 0000000000000040 ffff880209fb32c0 ffff880212e44200 ffffffff8107228f [ 78.293422] Call Trace: [ 78.293432] [<ffffffff812dfa0f>] ? dump_stack+0x5c/0x7d [ 78.293437] [<ffffffff81072224>] ? __warn+0xc4/0xe0 [ 78.293441] [<ffffffff8107228f>] ? warn_slowpath_fmt+0x4f/0x60 [ 78.293451] [<ffffffff810a46a2>] ? enqueue_task_fair+0xcd2/0x1260 [ 78.293463] [<ffffffffa001ec54>] ? usb_submit_urb+0x2b4/0x580 [usbcore] [ 78.293474] [<ffffffff8140c2e5>] ? __pm_runtime_resume+0x55/0x70 [ 78.293484] [<ffffffffa0825212>] ? _chaoskey_fill+0x132/0x250 [chaoskey] [ 78.293485] usbcore: registered new interface driver chaoskey [ 78.293493] [<ffffffff810aed50>] ? wait_woken+0x90/0x90 [ 78.293500] [<ffffffffa06448c0>] ? devm_hwrng_register+0x80/0x80 [rng_core] [ 78.293505] [<ffffffffa0825907>] ? chaoskey_rng_read+0x127/0x140 [chaoskey] [ 78.293511] [<ffffffffa06448c0>] ? devm_hwrng_register+0x80/0x80 [rng_core] [ 78.293515] [<ffffffffa064492e>] ? hwrng_fillfn+0x6e/0x120 [rng_core] [ 78.293520] [<ffffffff8108fb5f>] ? kthread+0xcf/0xf0 [ 78.293529] [<ffffffff81596d5f>] ? ret_from_fork+0x1f/0x40 [ 78.293535] [<ffffffff8108fa90>] ? kthread_park+0x50/0x50 Signed-off-by: Bob Ham <bob.ham@collabora.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
594 lines
14 KiB
C
594 lines
14 KiB
C
/*
|
|
* chaoskey - driver for ChaosKey device from Altus Metrum.
|
|
*
|
|
* This device provides true random numbers using a noise source based
|
|
* on a reverse-biased p-n junction in avalanche breakdown. More
|
|
* details can be found at http://chaoskey.org
|
|
*
|
|
* The driver connects to the kernel hardware RNG interface to provide
|
|
* entropy for /dev/random and other kernel activities. It also offers
|
|
* a separate /dev/ entry to allow for direct access to the random
|
|
* bit stream.
|
|
*
|
|
* Copyright © 2015 Keith Packard <keithp@keithp.com>
|
|
*
|
|
* 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; version 2 of the License.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/usb.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/hw_random.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
static struct usb_driver chaoskey_driver;
|
|
static struct usb_class_driver chaoskey_class;
|
|
static int chaoskey_rng_read(struct hwrng *rng, void *data,
|
|
size_t max, bool wait);
|
|
|
|
#define usb_dbg(usb_if, format, arg...) \
|
|
dev_dbg(&(usb_if)->dev, format, ## arg)
|
|
|
|
#define usb_err(usb_if, format, arg...) \
|
|
dev_err(&(usb_if)->dev, format, ## arg)
|
|
|
|
/* Version Information */
|
|
#define DRIVER_VERSION "v0.1"
|
|
#define DRIVER_AUTHOR "Keith Packard, keithp@keithp.com"
|
|
#define DRIVER_DESC "Altus Metrum ChaosKey driver"
|
|
#define DRIVER_SHORT "chaoskey"
|
|
|
|
MODULE_VERSION(DRIVER_VERSION);
|
|
MODULE_AUTHOR(DRIVER_AUTHOR);
|
|
MODULE_DESCRIPTION(DRIVER_DESC);
|
|
MODULE_LICENSE("GPL");
|
|
|
|
#define CHAOSKEY_VENDOR_ID 0x1d50 /* OpenMoko */
|
|
#define CHAOSKEY_PRODUCT_ID 0x60c6 /* ChaosKey */
|
|
|
|
#define ALEA_VENDOR_ID 0x12d8 /* Araneus */
|
|
#define ALEA_PRODUCT_ID 0x0001 /* Alea I */
|
|
|
|
#define CHAOSKEY_BUF_LEN 64 /* max size of USB full speed packet */
|
|
|
|
#define NAK_TIMEOUT (HZ) /* normal stall/wait timeout */
|
|
#define ALEA_FIRST_TIMEOUT (HZ*3) /* first stall/wait timeout for Alea */
|
|
|
|
#ifdef CONFIG_USB_DYNAMIC_MINORS
|
|
#define USB_CHAOSKEY_MINOR_BASE 0
|
|
#else
|
|
|
|
/* IOWARRIOR_MINOR_BASE + 16, not official yet */
|
|
#define USB_CHAOSKEY_MINOR_BASE 224
|
|
#endif
|
|
|
|
static const struct usb_device_id chaoskey_table[] = {
|
|
{ USB_DEVICE(CHAOSKEY_VENDOR_ID, CHAOSKEY_PRODUCT_ID) },
|
|
{ USB_DEVICE(ALEA_VENDOR_ID, ALEA_PRODUCT_ID) },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(usb, chaoskey_table);
|
|
|
|
static void chaos_read_callback(struct urb *urb);
|
|
|
|
/* Driver-local specific stuff */
|
|
struct chaoskey {
|
|
struct usb_interface *interface;
|
|
char in_ep;
|
|
struct mutex lock;
|
|
struct mutex rng_lock;
|
|
int open; /* open count */
|
|
bool present; /* device not disconnected */
|
|
bool reading; /* ongoing IO */
|
|
bool reads_started; /* track first read for Alea */
|
|
int size; /* size of buf */
|
|
int valid; /* bytes of buf read */
|
|
int used; /* bytes of buf consumed */
|
|
char *name; /* product + serial */
|
|
struct hwrng hwrng; /* Embedded struct for hwrng */
|
|
int hwrng_registered; /* registered with hwrng API */
|
|
wait_queue_head_t wait_q; /* for timeouts */
|
|
struct urb *urb; /* for performing IO */
|
|
char *buf;
|
|
};
|
|
|
|
static void chaoskey_free(struct chaoskey *dev)
|
|
{
|
|
if (dev) {
|
|
usb_dbg(dev->interface, "free");
|
|
usb_free_urb(dev->urb);
|
|
kfree(dev->name);
|
|
kfree(dev->buf);
|
|
kfree(dev);
|
|
}
|
|
}
|
|
|
|
static int chaoskey_probe(struct usb_interface *interface,
|
|
const struct usb_device_id *id)
|
|
{
|
|
struct usb_device *udev = interface_to_usbdev(interface);
|
|
struct usb_host_interface *altsetting = interface->cur_altsetting;
|
|
int i;
|
|
int in_ep = -1;
|
|
struct chaoskey *dev;
|
|
int result = -ENOMEM;
|
|
int size;
|
|
|
|
usb_dbg(interface, "probe %s-%s", udev->product, udev->serial);
|
|
|
|
/* Find the first bulk IN endpoint and its packet size */
|
|
for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
|
|
if (usb_endpoint_is_bulk_in(&altsetting->endpoint[i].desc)) {
|
|
in_ep = usb_endpoint_num(&altsetting->endpoint[i].desc);
|
|
size = usb_endpoint_maxp(&altsetting->endpoint[i].desc);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Validate endpoint and size */
|
|
if (in_ep == -1) {
|
|
usb_dbg(interface, "no IN endpoint found");
|
|
return -ENODEV;
|
|
}
|
|
if (size <= 0) {
|
|
usb_dbg(interface, "invalid size (%d)", size);
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (size > CHAOSKEY_BUF_LEN) {
|
|
usb_dbg(interface, "size reduced from %d to %d\n",
|
|
size, CHAOSKEY_BUF_LEN);
|
|
size = CHAOSKEY_BUF_LEN;
|
|
}
|
|
|
|
/* Looks good, allocate and initialize */
|
|
|
|
dev = kzalloc(sizeof(struct chaoskey), GFP_KERNEL);
|
|
|
|
if (dev == NULL)
|
|
goto out;
|
|
|
|
dev->buf = kmalloc(size, GFP_KERNEL);
|
|
|
|
if (dev->buf == NULL)
|
|
goto out;
|
|
|
|
dev->urb = usb_alloc_urb(0, GFP_KERNEL);
|
|
|
|
if (!dev->urb)
|
|
goto out;
|
|
|
|
usb_fill_bulk_urb(dev->urb,
|
|
udev,
|
|
usb_rcvbulkpipe(udev, in_ep),
|
|
dev->buf,
|
|
size,
|
|
chaos_read_callback,
|
|
dev);
|
|
|
|
/* Construct a name using the product and serial values. Each
|
|
* device needs a unique name for the hwrng code
|
|
*/
|
|
|
|
if (udev->product && udev->serial) {
|
|
dev->name = kmalloc(strlen(udev->product) + 1 +
|
|
strlen(udev->serial) + 1, GFP_KERNEL);
|
|
if (dev->name == NULL)
|
|
goto out;
|
|
|
|
strcpy(dev->name, udev->product);
|
|
strcat(dev->name, "-");
|
|
strcat(dev->name, udev->serial);
|
|
}
|
|
|
|
dev->interface = interface;
|
|
|
|
dev->in_ep = in_ep;
|
|
|
|
if (udev->descriptor.idVendor != ALEA_VENDOR_ID)
|
|
dev->reads_started = 1;
|
|
|
|
dev->size = size;
|
|
dev->present = 1;
|
|
|
|
init_waitqueue_head(&dev->wait_q);
|
|
|
|
mutex_init(&dev->lock);
|
|
mutex_init(&dev->rng_lock);
|
|
|
|
usb_set_intfdata(interface, dev);
|
|
|
|
result = usb_register_dev(interface, &chaoskey_class);
|
|
if (result) {
|
|
usb_err(interface, "Unable to allocate minor number.");
|
|
goto out;
|
|
}
|
|
|
|
dev->hwrng.name = dev->name ? dev->name : chaoskey_driver.name;
|
|
dev->hwrng.read = chaoskey_rng_read;
|
|
|
|
/* Set the 'quality' metric. Quality is measured in units of
|
|
* 1/1024's of a bit ("mills"). This should be set to 1024,
|
|
* but there is a bug in the hwrng core which masks it with
|
|
* 1023.
|
|
*
|
|
* The patch that has been merged to the crypto development
|
|
* tree for that bug limits the value to 1024 at most, so by
|
|
* setting this to 1024 + 1023, we get 1023 before the fix is
|
|
* merged and 1024 afterwards. We'll patch this driver once
|
|
* both bits of code are in the same tree.
|
|
*/
|
|
dev->hwrng.quality = 1024 + 1023;
|
|
|
|
dev->hwrng_registered = (hwrng_register(&dev->hwrng) == 0);
|
|
if (!dev->hwrng_registered)
|
|
usb_err(interface, "Unable to register with hwrng");
|
|
|
|
usb_enable_autosuspend(udev);
|
|
|
|
usb_dbg(interface, "chaoskey probe success, size %d", dev->size);
|
|
return 0;
|
|
|
|
out:
|
|
usb_set_intfdata(interface, NULL);
|
|
chaoskey_free(dev);
|
|
return result;
|
|
}
|
|
|
|
static void chaoskey_disconnect(struct usb_interface *interface)
|
|
{
|
|
struct chaoskey *dev;
|
|
|
|
usb_dbg(interface, "disconnect");
|
|
dev = usb_get_intfdata(interface);
|
|
if (!dev) {
|
|
usb_dbg(interface, "disconnect failed - no dev");
|
|
return;
|
|
}
|
|
|
|
if (dev->hwrng_registered)
|
|
hwrng_unregister(&dev->hwrng);
|
|
|
|
usb_deregister_dev(interface, &chaoskey_class);
|
|
|
|
usb_set_intfdata(interface, NULL);
|
|
mutex_lock(&dev->lock);
|
|
|
|
dev->present = 0;
|
|
usb_poison_urb(dev->urb);
|
|
|
|
if (!dev->open) {
|
|
mutex_unlock(&dev->lock);
|
|
chaoskey_free(dev);
|
|
} else
|
|
mutex_unlock(&dev->lock);
|
|
|
|
usb_dbg(interface, "disconnect done");
|
|
}
|
|
|
|
static int chaoskey_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct chaoskey *dev;
|
|
struct usb_interface *interface;
|
|
|
|
/* get the interface from minor number and driver information */
|
|
interface = usb_find_interface(&chaoskey_driver, iminor(inode));
|
|
if (!interface)
|
|
return -ENODEV;
|
|
|
|
usb_dbg(interface, "open");
|
|
|
|
dev = usb_get_intfdata(interface);
|
|
if (!dev) {
|
|
usb_dbg(interface, "open (dev)");
|
|
return -ENODEV;
|
|
}
|
|
|
|
file->private_data = dev;
|
|
mutex_lock(&dev->lock);
|
|
++dev->open;
|
|
mutex_unlock(&dev->lock);
|
|
|
|
usb_dbg(interface, "open success");
|
|
return 0;
|
|
}
|
|
|
|
static int chaoskey_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct chaoskey *dev = file->private_data;
|
|
struct usb_interface *interface;
|
|
|
|
if (dev == NULL)
|
|
return -ENODEV;
|
|
|
|
interface = dev->interface;
|
|
|
|
usb_dbg(interface, "release");
|
|
|
|
mutex_lock(&dev->lock);
|
|
|
|
usb_dbg(interface, "open count at release is %d", dev->open);
|
|
|
|
if (dev->open <= 0) {
|
|
usb_dbg(interface, "invalid open count (%d)", dev->open);
|
|
mutex_unlock(&dev->lock);
|
|
return -ENODEV;
|
|
}
|
|
|
|
--dev->open;
|
|
|
|
if (!dev->present) {
|
|
if (dev->open == 0) {
|
|
mutex_unlock(&dev->lock);
|
|
chaoskey_free(dev);
|
|
} else
|
|
mutex_unlock(&dev->lock);
|
|
} else
|
|
mutex_unlock(&dev->lock);
|
|
|
|
usb_dbg(interface, "release success");
|
|
return 0;
|
|
}
|
|
|
|
static void chaos_read_callback(struct urb *urb)
|
|
{
|
|
struct chaoskey *dev = urb->context;
|
|
int status = urb->status;
|
|
|
|
usb_dbg(dev->interface, "callback status (%d)", status);
|
|
|
|
if (status == 0)
|
|
dev->valid = urb->actual_length;
|
|
else
|
|
dev->valid = 0;
|
|
|
|
dev->used = 0;
|
|
|
|
/* must be seen first before validity is announced */
|
|
smp_wmb();
|
|
|
|
dev->reading = false;
|
|
wake_up(&dev->wait_q);
|
|
}
|
|
|
|
/* Fill the buffer. Called with dev->lock held
|
|
*/
|
|
static int _chaoskey_fill(struct chaoskey *dev)
|
|
{
|
|
DEFINE_WAIT(wait);
|
|
int result;
|
|
bool started;
|
|
|
|
usb_dbg(dev->interface, "fill");
|
|
|
|
/* Return immediately if someone called before the buffer was
|
|
* empty */
|
|
if (dev->valid != dev->used) {
|
|
usb_dbg(dev->interface, "not empty yet (valid %d used %d)",
|
|
dev->valid, dev->used);
|
|
return 0;
|
|
}
|
|
|
|
/* Bail if the device has been removed */
|
|
if (!dev->present) {
|
|
usb_dbg(dev->interface, "device not present");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* Make sure the device is awake */
|
|
result = usb_autopm_get_interface(dev->interface);
|
|
if (result) {
|
|
usb_dbg(dev->interface, "wakeup failed (result %d)", result);
|
|
return result;
|
|
}
|
|
|
|
dev->reading = true;
|
|
result = usb_submit_urb(dev->urb, GFP_KERNEL);
|
|
if (result < 0) {
|
|
result = usb_translate_errors(result);
|
|
dev->reading = false;
|
|
goto out;
|
|
}
|
|
|
|
/* The first read on the Alea takes a little under 2 seconds.
|
|
* Reads after the first read take only a few microseconds
|
|
* though. Presumably the entropy-generating circuit needs
|
|
* time to ramp up. So, we wait longer on the first read.
|
|
*/
|
|
started = dev->reads_started;
|
|
dev->reads_started = true;
|
|
result = wait_event_interruptible_timeout(
|
|
dev->wait_q,
|
|
!dev->reading,
|
|
(started ? NAK_TIMEOUT : ALEA_FIRST_TIMEOUT) );
|
|
|
|
if (result < 0)
|
|
goto out;
|
|
|
|
if (result == 0)
|
|
result = -ETIMEDOUT;
|
|
else
|
|
result = dev->valid;
|
|
out:
|
|
/* Let the device go back to sleep eventually */
|
|
usb_autopm_put_interface(dev->interface);
|
|
|
|
usb_dbg(dev->interface, "read %d bytes", dev->valid);
|
|
|
|
return result;
|
|
}
|
|
|
|
static ssize_t chaoskey_read(struct file *file,
|
|
char __user *buffer,
|
|
size_t count,
|
|
loff_t *ppos)
|
|
{
|
|
struct chaoskey *dev;
|
|
ssize_t read_count = 0;
|
|
int this_time;
|
|
int result = 0;
|
|
unsigned long remain;
|
|
|
|
dev = file->private_data;
|
|
|
|
if (dev == NULL || !dev->present)
|
|
return -ENODEV;
|
|
|
|
usb_dbg(dev->interface, "read %zu", count);
|
|
|
|
while (count > 0) {
|
|
|
|
/* Grab the rng_lock briefly to ensure that the hwrng interface
|
|
* gets priority over other user access
|
|
*/
|
|
result = mutex_lock_interruptible(&dev->rng_lock);
|
|
if (result)
|
|
goto bail;
|
|
mutex_unlock(&dev->rng_lock);
|
|
|
|
result = mutex_lock_interruptible(&dev->lock);
|
|
if (result)
|
|
goto bail;
|
|
if (dev->valid == dev->used) {
|
|
result = _chaoskey_fill(dev);
|
|
if (result < 0) {
|
|
mutex_unlock(&dev->lock);
|
|
goto bail;
|
|
}
|
|
}
|
|
|
|
this_time = dev->valid - dev->used;
|
|
if (this_time > count)
|
|
this_time = count;
|
|
|
|
remain = copy_to_user(buffer, dev->buf + dev->used, this_time);
|
|
if (remain) {
|
|
result = -EFAULT;
|
|
|
|
/* Consume the bytes that were copied so we don't leak
|
|
* data to user space
|
|
*/
|
|
dev->used += this_time - remain;
|
|
mutex_unlock(&dev->lock);
|
|
goto bail;
|
|
}
|
|
|
|
count -= this_time;
|
|
read_count += this_time;
|
|
buffer += this_time;
|
|
dev->used += this_time;
|
|
mutex_unlock(&dev->lock);
|
|
}
|
|
bail:
|
|
if (read_count) {
|
|
usb_dbg(dev->interface, "read %zu bytes", read_count);
|
|
return read_count;
|
|
}
|
|
usb_dbg(dev->interface, "empty read, result %d", result);
|
|
if (result == -ETIMEDOUT)
|
|
result = -EAGAIN;
|
|
return result;
|
|
}
|
|
|
|
static int chaoskey_rng_read(struct hwrng *rng, void *data,
|
|
size_t max, bool wait)
|
|
{
|
|
struct chaoskey *dev = container_of(rng, struct chaoskey, hwrng);
|
|
int this_time;
|
|
|
|
usb_dbg(dev->interface, "rng_read max %zu wait %d", max, wait);
|
|
|
|
if (!dev->present) {
|
|
usb_dbg(dev->interface, "device not present");
|
|
return 0;
|
|
}
|
|
|
|
/* Hold the rng_lock until we acquire the device lock so that
|
|
* this operation gets priority over other user access to the
|
|
* device
|
|
*/
|
|
mutex_lock(&dev->rng_lock);
|
|
|
|
mutex_lock(&dev->lock);
|
|
|
|
mutex_unlock(&dev->rng_lock);
|
|
|
|
/* Try to fill the buffer if empty. It doesn't actually matter
|
|
* if _chaoskey_fill works; we'll just return zero bytes as
|
|
* the buffer will still be empty
|
|
*/
|
|
if (dev->valid == dev->used)
|
|
(void) _chaoskey_fill(dev);
|
|
|
|
this_time = dev->valid - dev->used;
|
|
if (this_time > max)
|
|
this_time = max;
|
|
|
|
memcpy(data, dev->buf + dev->used, this_time);
|
|
|
|
dev->used += this_time;
|
|
|
|
mutex_unlock(&dev->lock);
|
|
|
|
usb_dbg(dev->interface, "rng_read this_time %d\n", this_time);
|
|
return this_time;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
static int chaoskey_suspend(struct usb_interface *interface,
|
|
pm_message_t message)
|
|
{
|
|
usb_dbg(interface, "suspend");
|
|
return 0;
|
|
}
|
|
|
|
static int chaoskey_resume(struct usb_interface *interface)
|
|
{
|
|
usb_dbg(interface, "resume");
|
|
return 0;
|
|
}
|
|
#else
|
|
#define chaoskey_suspend NULL
|
|
#define chaoskey_resume NULL
|
|
#endif
|
|
|
|
/* file operation pointers */
|
|
static const struct file_operations chaoskey_fops = {
|
|
.owner = THIS_MODULE,
|
|
.read = chaoskey_read,
|
|
.open = chaoskey_open,
|
|
.release = chaoskey_release,
|
|
.llseek = default_llseek,
|
|
};
|
|
|
|
/* class driver information */
|
|
static struct usb_class_driver chaoskey_class = {
|
|
.name = "chaoskey%d",
|
|
.fops = &chaoskey_fops,
|
|
.minor_base = USB_CHAOSKEY_MINOR_BASE,
|
|
};
|
|
|
|
/* usb specific object needed to register this driver with the usb subsystem */
|
|
static struct usb_driver chaoskey_driver = {
|
|
.name = DRIVER_SHORT,
|
|
.probe = chaoskey_probe,
|
|
.disconnect = chaoskey_disconnect,
|
|
.suspend = chaoskey_suspend,
|
|
.resume = chaoskey_resume,
|
|
.reset_resume = chaoskey_resume,
|
|
.id_table = chaoskey_table,
|
|
.supports_autosuspend = 1,
|
|
};
|
|
|
|
module_usb_driver(chaoskey_driver);
|
|
|