No USB hub I have tried actually seems to support "Hub Port Power Control" properly that is required for USB 2.0 compliance.
The USB 2.0 standard states that :
Self-powered hubs may have power switches that control delivery of power downstream facing ports but it is not required. Bus-powered hubs are required to have power switches. A hub with power switches can switch power to all ports as a group/gang, to each port individually, or have an arbitrary number of gangs of one or more ports. A hub indicates whether or not it supports power switching by the setting of the Logical Power Switching Mode field in wHubCharacteristics. If a hub supports per-port power switching, then the power to a port is turned on when a SetPortFeature(PORT_POWER) request is received for the port. Port power is turned off when the port is in the Powered-off or Not Configured states. If a hub supports ganged power switching, then the power to all ports in a gang is turned on when any port in a gang receives a SetPortFeature(PORT_POWER) request. The power to a gang is not turned off unless all ports in a gang are in the Powered-off or Not Configured states.
Although a self-powered hub is not required to implement power switching, the hub must support the Powered-off state for all ports. Additionally, the hub must implement the PortPwrCtrlMask (all bits set to 1B) even though the hub has no power switches that can be controlled by the USB System Software.
In Linux most chipsets seems to support this feature when doing
lusb -v as specified under the
wHubCharacteristics field. But when actually trying to use it nothing happens, it is not possible to turn off the power for any port (or even all of them).
I guess this is because the hardware manufacturers never bothered to actually wire up this support, even though the chipset support it, leading people to do hacks like this
So my question is:
Does anyone have a list with hardware the properly support USB Port Power control?
Specifically it would be nice with both model and batch numbers, since support may differ between different revisions.