usb udev - 润新知

usb udev
[root@localhost ~] # udevadm monitor
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent

KERNEL[105.208635] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/bsg/4:0:0:0 (bsg)
KERNEL[105.208721] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_generic/sg1 (scsi_generic)
KERNEL[105.208764] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_device/4:0:0:0 (scsi_device)
KERNEL[105.208836] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_disk/4:0:0:0 (scsi_disk)
KERNEL[105.209093] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb/sdb4 (block)
UDEV [105.211112] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/bsg/4:0:0:0 (bsg)
UDEV [105.212047] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_generic/sg1 (scsi_generic)
KERNEL[105.213199] remove /devices/virtual/bdi/8:16 (bdi)
KERNEL[105.213516] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb (block)
KERNEL[105.213585] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0 (scsi)
UDEV [105.213641] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_device/4:0:0:0 (scsi_device)
UDEV [105.213998] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_disk/4:0:0:0 (scsi_disk)
UDEV [105.214105] remove /devices/virtual/bdi/8:16 (bdi)
UDEV [105.214980] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb/sdb4 (block)
UDEV [105.216450] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb (block)
UDEV [105.217848] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0 (scsi)
KERNEL[105.221213] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0 (scsi)
KERNEL[105.221232] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/scsi_host/host4 (scsi_host)
KERNEL[105.221240] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4 (scsi)
KERNEL[105.221284] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0 (usb)
KERNEL[105.221557] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1 (usb)
UDEV [105.221673] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0 (scsi)
UDEV [105.221769] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/scsi_host/host4 (scsi_host)
UDEV [105.221885] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4 (scsi)
UDEV [105.222110] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0 (usb)
UDEV [105.222325] remove /devices/pci0000:00/0000:00:14.0/usb2/2-1 (usb)

KERNEL[128.272086] add KERNEL[128.283096] add KERNEL[128.283566] add KERNEL[128.283617] add UDEV [128.292000] add UDEV [128.294367] add UDEV [128.296326] add UDEV [128.298073] add KERNEL[129.311851] add KERNEL[129.311874] add KERNEL[129.311880] add KERNEL[129.311886] add KERNEL[129.311894] add KERNEL[129.311913] add KERNEL[129.312405] add UDEV [129.312474] add UDEV [129.312773] add UDEV [129.312910] add UDEV [129.313439] add UDEV [129.313483] add UDEV [129.313685] add UDEV [129.313707] add KERNEL[129.314981] add KERNEL[129.314993] add UDEV [129.346675] add UDEV [129.374249] add /devices/pci0000:00/0000:00:14.0/usb2/2-1 (usb)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0 (usb)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4 (scsi)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/scsi_host/host4 (scsi_host)
/devices/pci0000:00/0000:00:14.0/usb2/2-1 (usb)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0 (usb)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4 (scsi)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/scsi_host/host4 (scsi_host)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0 (scsi)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0 (scsi)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_disk/4:0:0:0 (scsi_disk)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_device/4:0:0:0 (scsi_device)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_generic/sg1 (scsi_generic)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/bsg/4:0:0:0 (bsg)
/devices/virtual/bdi/8:16 (bdi)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0 (scsi)
/devices/virtual/bdi/8:16 (bdi)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0 (scsi)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_device/4:0:0:0 (scsi_device)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_disk/4:0:0:0 (scsi_disk)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/bsg/4:0:0:0 (bsg)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/scsi_generic/sg1 (scsi_generic)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb (block)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb/sdb4 (block)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb (block)
/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host4/target4:0:0/4:0:0:0/block/sdb/sdb4 (block)

[10月24 23:38] sdb: sdb4
[10月24 23:39] usb 2-1: USB disconnect, device number 2
[ +23.032664] usb 2-1: new SuperSpeed USB device number 3 using xhci_hcd
[ +0.023654] usb 2-1: New USB device found, idVendor=0951, idProduct=1666
[ +0.000005] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ +0.000003] usb 2-1: Product: DataTraveler 3.0
[ +0.000003] usb 2-1: Manufacturer: Kingston
[ +0.000002] usb 2-1: SerialNumber: 0026186645E5F0C078808600
[ +0.011328] usb-storage 2-1:1.0: USB Mass Storage device detected
[ +0.000359] scsi host4: usb-storage 2-1:1.0
[ +1.027962] scsi 4:0:0:0: Direct-Access Kingston DataTraveler 3.0 PQ: 0 ANSI: 6
[ +0.000176] sd 4:0:0:0: Attached scsi generic sg1 type 0
[ +0.000207] sd 4:0:0:0: [sdb] 30218842 512-byte logical blocks: (15.5 GB/14.4 GiB)
[ +0.000144] sd 4:0:0:0: [sdb] Write Protect is off
[ +0.000000] sd 4:0:0:0: [sdb] Mode Sense: 4f 00 00 00
[ +0.000142] sd 4:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ +0.002550] sdb: sdb4
[ +0.000741] sd 4:0:0:0: [sdb] Attached SCSI removable disk
```
    /* usbreset -- send a USB port reset to a USB device */

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>

#include <linux/usbdevice_fs.h>


int main(int argc, char **argv)
{
    const char *filename;
    int fd;
    int rc;

    if (argc != 2) {
        fprintf(stderr, "Usage: usbreset device-filename
");
        return 1;
    }
    filename = argv[1];

    fd = open(filename, O_WRONLY);
    if (fd < 0) {
        perror("Error opening output file");
        return 1;
    }

    printf("Resetting USB device %s
", filename);
    rc = ioctl(fd, USBDEVFS_RESET, 0);
    if (rc < 0) {
        perror("Error in ioctl");
        return 1;
    }
    printf("Reset successful
");

    close(fd);
    return 0;
}
```
https://askubuntu.com/questions/645/how-do-you-reset-a-usb-device-from-the-command-line
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原文地址：https://www.cnblogs.com/fangying7/p/7726494.html