USB_MAKE_PATH(9) Host-Side Data Types and Macro USB_MAKE_PATH(9)NAME
usb_make_path - returns stable device path in the usb tree
int usb_make_path(struct usb_device * dev, char * buf, size_t size);
the device whose path is being constructed
where to put the string
how big is "buf"?
Length of the string (> 0) or negative if size was too small.
This identifier is intended to be "stable", reflecting physical paths in hardware such as physical bus addresses for host controllers or
ports on USB hubs. That makes it stay the same until systems are physically reconfigured, by re-cabling a tree of USB devices or by moving
USB host controllers. Adding and removing devices, including virtual root hubs in host controller driver modules, does not change these
path identifiers; neither does rebooting or re-enumerating. These are more useful identifiers than changeable ("unstable") ones like bus
numbers or device addresses.
With a partial exception for devices connected to USB 2.0 root hubs, these identifiers are also predictable. So long as the device tree
isn't changed, plugging any USB device into a given hub port always gives it the same path. Because of the use of "companion" controllers,
devices connected to ports on USB 2.0 root hubs (EHCI host controllers) will get one path ID if they are high speed, and a different one if
they are full or low speed.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 USB_MAKE_PATH(9)
Check Out this Related Man Page
EHCI(4) BSD Kernel Interfaces Manual EHCI(4)NAME
ehci -- USB Enhanced Host Controller driver
ehci* at cardbus? function ?
ehci* at pci? dev ? function ?
usb* at ehci?
The ehci driver provides support for the USB Enhanced Host Controller Interface, which is used by USB 2.0 controllers.
EHCI controllers are peculiar in that they can only handle the USB 2.0 protocol. This means that they normally have one or more companion
controllers (i.e., ohci(4) or uhci(4)) handling USB 1.x devices. Consequently each USB connector is electrically connected to two USB con-
trollers. The handling of this is totally automatic, but can be noticed since USB 1.x and USB 2.0 devices plugged in to the same connector
appear to connect to different USB busses.
SEE ALSO cardbus(4), ohci(4), pci(4), uhci(4), usb(4)HISTORY
The ehci driver appeared in NetBSD 1.6.
The support for hubs that are connected with high speed upstream and low or full speed downstream (i.e., for transaction translators) is lim-
BSD Aug 10, 2008 BSD
I am trying to get a flash card reader to work with my machine. My question is, are all of my USB ports screwed up? Do I need to buy a seperate USB controller? I does not appear that the onboard USB ports work.
In trying to get it to work, I typed cat /proc/scsi/scsi and got this:
# cat... (2 Replies)
Have connected a non-IBM storage device to AIX host via fibre channel. If the storage is rebooted or a raid controller fails over whilst connected to the host, the paths that drop do not come back online when the ports become active again.
I have tried enabling dynamic tracking and delayed_fail... (3 Replies)
My name is Patrik Mark.S . i am using the Vxworks 653 OS with HPCNET Board with 8641D processor, Since there is no USB Host Stack in Vxworks 653 so i am tring to port UsbHost Stack onto vxworks 653. at the lowest layer(HCD Layer) of usb Host stack i need usbPciStub.c File related to my Board... (1 Reply)
I want to watch the USB ports.
If any device is connected to the USB port I want to take the name of the device and
I want to log the device name. how to watch all the USB ports.
How to find the device is connected in which usb port. (1 Reply)