USB
Table of Contents
From the terminal the lsusb command may be used to view USB devices.
USB-C Flash drive
card825gen2:~$ lsusb -t /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M |__ Port 1: Dev 2, If 0, Class=Mass Storage, Driver=usb-storage, 5000M /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 5000M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 3: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid, 12M
USB3 flash drive plugged into blue host connector closest to circuit board
card825gen2:~$ lsusb -t /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 5000M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 1: Dev 4, If 0, Class=Mass Storage, Driver=usb-storage, 480M |__ Port 3: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid, 12M
USB3 flash drive plugged into blue host connector farther from circuit board
card825gen2:~$ lsusb -t /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 5000M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 2: Dev 5, If 0, Class=Mass Storage, Driver=usb-storage, 480M |__ Port 3: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid, 12M
USB2 flash drive plugged into black USB2 connector
card825gen2:~$ lsusb -t /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 5000M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 3: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid, 12M |__ Port 4: Dev 6, If 0, Class=Mass Storage, Driver=usb-storage, 480M
USB2 flash drive plugged into blue host connector closest to circuit board
card825gen2:~$ lsusb -t /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 5000M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 1: Dev 7, If 0, Class=Mass Storage, Driver=usb-storage, 480M |__ Port 3: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid, 12M
USB2 flash drive plugged into blue host connector farther from circuit board
card825gen2:~$ lsusb -t /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 5000M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M |__ Port 2: Dev 8, If 0, Class=Mass Storage, Driver=usb-storage, 480M |__ Port 3: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid, 12M
The sysfs filesystem /sys can be used to detect USB devices.
Sysfs nothing plugged into 825 USB
card825gen2:/sys/bus/usb/devices$ ls 1-0:1.0 1-1 1-1.3 1-1.3:1.0 1-1:1.0 2-0:1.0 2-1 2-1:1.0 3-0:1.0 4-0:1.0 usb1 usb2 usb3 usb4
USB-C flash drive plugged in
card825gen2:/sys/bus/usb/devices$ ls 1-0:1.0 1-1 1-1.3 1-1.3:1.0 1-1:1.0 2-0:1.0 2-1 2-1:1.0 3-0:1.0 4-0:1.0 4-1 4-1:1.0 usb1 usb2 usb3 usb4
card825gen2:/sys/bus/usb/devices$ cat /sys/bus/usb/devices/4-1/product SanDisk 3.2Gen1
USB-3 flash drive plugged into blue host port closest to circuit board
card825gen2:/sys/bus/usb/devices$ ls 1-0:1.0 1-1.1 1-1.3 1-1:1.0 2-1 3-0:1.0 usb1 usb3 1-1 1-1.1:1.0 1-1.3:1.0 2-0:1.0 2-1:1.0 4-0:1.0 usb2 usb4
card825gen2:/sys/bus/usb/devices$ cat /sys/bus/usb/devices/1-1.1/product Cruzer
USB-3 flash drive plugged into blue host port farther from circuit board
card825gen2:/sys/bus/usb/devices$ ls 1-0:1.0 1-1.2 1-1.3 1-1:1.0 2-1 3-0:1.0 usb1 usb3 1-1 1-1.2:1.0 1-1.3:1.0 2-0:1.0 2-1:1.0 4-0:1.0 usb2 usb4 card825gen2:/sys/bus/usb/devices$ cat /sys/bus/usb/devices/1-1.2/product Cruzer
USB-2 flash drive plugged into black USB-2 host port
card825gen2:/sys/bus/usb/devices$ ls 1-0:1.0 1-1.3 1-1.4 1-1:1.0 2-1 3-0:1.0 usb1 usb3 1-1 1-1.3:1.0 1-1.4:1.0 2-0:1.0 2-1:1.0 4-0:1.0 usb2 usb4 card825gen2:/sys/bus/usb/devices$ cat /sys/bus/usb/devices/1-1.4/product Mass storage
USB-3 flash drive plugged into black USB-2 host port
card825gen2:/sys/bus/usb/devices$ ls 1-0:1.0 1-1.3 1-1.4 1-1:1.0 2-1 3-0:1.0 usb1 usb3 1-1 1-1.3:1.0 1-1.4:1.0 2-0:1.0 2-1:1.0 4-0:1.0 usb2 usb4 card825gen2:/sys/bus/usb/devices$ cat /sys/bus/usb/devices/1-1.4/product Cruzer card825gen2:/sys/bus/usb/devices$ cat /sys/bus/usb/devices/1-1.4/product SanDisk 3.2Gen1
To programmatically detect what is plugged into each port the sysfs file tree may be read. The following example demonstrates a method of checking each port and reading the desciption of any attached devices.
typedef struct { const char* portName; const char* sysfsPath; const char* usb2sysfsPath; } USBPortInfo_t; const USBPortInfo_t usbPortInfo[] = { { "USB2", "/sys/bus/usb/devices/1-1.4", NULL }, { "USB3-1", "/sys/bus/usb/devices/2-1.1", "/sys/bus/usb/devices/1-1.1" }, { "USB3-2", "/sys/bus/usb/devices/2-1.2", "/sys/bus/usb/devices/1-1.2" }, { "USB-C", "/sys/bus/usb/devices/4-1", NULL }, }; void ScanUSBports(void) { int n; char tmp[100]; struct stat st; FILE* file; const char* pathFound; typedef enum { noUsb, usbFound, usb2Found } USBFound_t; USBFound_t found = noUsb; for(n = 0; n < ARRAY_ELEMS(usbPortInfo); n++) { if(stat(usbPortInfo[n].sysfsPath, &st) == 0) { found = usbFound; pathFound = usbPortInfo[n].sysfsPath; } else if((usbPortInfo[n].usb2sysfsPath != NULL) && (stat(usbPortInfo[n].usb2sysfsPath, &st) == 0)) { found = usb2Found; pathFound = usbPortInfo[n].usb2sysfsPath; } else { found = noUsb; } if(found != noUsb) { sprintf_s(tmp, "%s/product", pathFound); file = fopen(tmp, "r"); if(file != NULL) { if(found == usb2Found) { strcpy(tmp, "*USB2* "); fgets(tmp + 7, sizeof(tmp) - 7, file); } else { fgets(tmp, sizeof(tmp), file); } printf("%s [%s]\r\n", usbPortInfo[n].portName, tmp); fclose(file); } }