openwrtv4/package/utils/usbreset/src/usbreset.c
Jo-Philipp Wich 97c59cea1f usbreset: fix possible access to uninitialized variable (#15041)
Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

SVN-Revision: 39738
2014-02-23 23:42:12 +00:00

235 lines
4.8 KiB
C

/* usbreset -- send a USB port reset to a USB device */
/*
http://marc.info/?l=linux-usb-users&m=116827193506484&w=2
and needs mounted usbfs filesystem
sudo mount -t usbfs none /proc/bus/usb
There is a way to suspend a USB device. In order to use it,
you must have a kernel with CONFIG_PM_SYSFS_DEPRECATED turned on. To
suspend a device, do (as root):
echo -n 2 >/sys/bus/usb/devices/.../power/state
where the "..." is the ID for your device. To unsuspend, do the same
thing but with a "0" instead of the "2" above.
Note that this mechanism is slated to be removed from the kernel within
the next year. Hopefully some other mechanism will take its place.
> To reset a
> device?
Here's a program to do it. You invoke it as either
usbreset /proc/bus/usb/BBB/DDD
or
usbreset /dev/usbB.D
depending on how your system is set up, where BBB and DDD are the bus and
device address numbers.
Alan Stern
*/
#include <stdio.h>
#include <stdbool.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <limits.h>
#include <dirent.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <linux/usbdevice_fs.h>
static char *usbfs = NULL;
struct usbentry {
int bus_num;
int dev_num;
int vendor_id;
int product_id;
char vendor_name[128];
char product_name[128];
};
static char *sysfs_attr(const char *dev, const char *attr)
{
int fd, len = 0;
char path[PATH_MAX];
static char buf[129];
memset(buf, 0, sizeof(buf));
snprintf(path, sizeof(path) - 1, "/sys/bus/usb/devices/%s/%s", dev, attr);
if ((fd = open(path, O_RDONLY)) >= 0)
{
len = read(fd, buf, sizeof(buf) - 1);
close(fd);
}
while (--len > 0 && isspace(buf[len]))
buf[len] = 0;
return (len >= 0) ? buf : NULL;
}
static struct usbentry * parse_devlist(DIR *d)
{
char *attr;
struct dirent *e;
static struct usbentry dev;
do {
e = readdir(d);
if (!e)
return NULL;
}
while(!isdigit(e->d_name[0]) || strchr(e->d_name, ':'));
memset(&dev, 0, sizeof(dev));
if ((attr = sysfs_attr(e->d_name, "busnum")) != NULL)
dev.bus_num = strtoul(attr, NULL, 10);
if ((attr = sysfs_attr(e->d_name, "devnum")) != NULL)
dev.dev_num = strtoul(attr, NULL, 10);
if ((attr = sysfs_attr(e->d_name, "idVendor")) != NULL)
dev.vendor_id = strtoul(attr, NULL, 16);
if ((attr = sysfs_attr(e->d_name, "idProduct")) != NULL)
dev.product_id = strtoul(attr, NULL, 16);
if ((attr = sysfs_attr(e->d_name, "manufacturer")) != NULL)
strcpy(dev.vendor_name, attr);
if ((attr = sysfs_attr(e->d_name, "product")) != NULL)
strcpy(dev.product_name, attr);
if (dev.bus_num && dev.dev_num && dev.vendor_id && dev.product_id)
return &dev;
return NULL;
}
static void list_devices(void)
{
DIR *devs = opendir("/sys/bus/usb/devices");
struct usbentry *dev;
if (!devs)
return;
while ((dev = parse_devlist(devs)) != NULL)
{
printf(" Number %03d/%03d ID %04x:%04x %s\n",
dev->bus_num, dev->dev_num,
dev->vendor_id, dev->product_id,
dev->product_name);
}
closedir(devs);
}
struct usbentry * find_device(int *bus, int *dev,
int *vid, int *pid,
const char *product)
{
DIR *devs = opendir("/sys/bus/usb/devices");
struct usbentry *e, *match = NULL;
if (!devs)
return NULL;
while ((e = parse_devlist(devs)) != NULL)
{
if ((bus && (e->bus_num == *bus) && (e->dev_num == *dev)) ||
(vid && (e->vendor_id == *vid) && (e->product_id == *pid)) ||
(product && !strcasecmp(e->product_name, product)))
{
match = e;
break;
}
}
closedir(devs);
return match;
}
static void reset_device(struct usbentry *dev)
{
int fd;
char path[PATH_MAX];
snprintf(path, sizeof(path) - 1, "/dev/bus/usb/%03d/%03d",
dev->bus_num, dev->dev_num);
printf("Resetting %s ... ", dev->product_name);
if ((fd = open(path, O_WRONLY)) > -1)
{
if (ioctl(fd, USBDEVFS_RESET, 0) < 0)
printf("failed [%s]\n", strerror(errno));
else
printf("ok\n");
close(fd);
}
else
{
printf("can't open [%s]\n", strerror(errno));
}
}
int main(int argc, char **argv)
{
int id1, id2;
struct usbentry *dev;
if ((argc == 2) && (sscanf(argv[1], "%3d/%3d", &id1, &id2) == 2))
{
dev = find_device(&id1, &id2, NULL, NULL, NULL);
}
else if ((argc == 2) && (sscanf(argv[1], "%4x:%4x", &id1, &id2) == 2))
{
dev = find_device(NULL, NULL, &id1, &id2, NULL);
}
else if ((argc == 2) && strlen(argv[1]) < 128)
{
dev = find_device(NULL, NULL, NULL, NULL, argv[1]);
}
else
{
printf("Usage:\n"
" usbreset PPPP:VVVV - reset by product and vendor id\n"
" usbreset BBB/DDD - reset by bus and device number\n"
" usbreset \"Product\" - reset by product name\n\n"
"Devices:\n");
list_devices();
return 1;
}
if (!dev)
{
fprintf(stderr, "No such device found\n");
return 1;
}
reset_device(dev);
return 0;
}