On 23.08.2017 10:35, Jack Pham wrote:
To perform SuperSpeed compliance testing the port should first be placed into compliance mode. For xHCI 1.0 and prior this transition happens automatically when the port is in Training and encounters an LFPS timeout. Thus running compliance tests against a test appliance may simply just work by simply plugging in to the downstream port. However starting with xHCI 1.1 the transition from Polling.LFPS to compliance mode may be disabled by default and needs to be explicitly enabled by writing to the PLS field of the PORTSC register, which sets an internal 'CTE' (Compliance Transition Enabled) flag so that the port will perform the transition the next time it encounters LFPS timeout. Whether this is disabled or not is determined by the 'CTC' (Compliance Transition Capability) bit in the HCCPARAMS2 capability register. In order to allow a test operator to change this if needed, allow a test driver (such as drivers/usb/misc/lvstest.c) to send a SET_FEATURE(PORT_LINK_STATE) control message to the root hub to update the link state prior to connecting to the port. Subsequently, placing the port in warm reset would then disable the flag. Signed-off-by: Jack Pham <jackp@xxxxxxxxxxxxxx> --- drivers/usb/host/xhci-hub.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+)
For this patch, the xhci changes: Acked-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
