On Mon, 21 Dec 2015, Vikas Bansal wrote: > Pre-Condition > At the time of reset resume of a USB device, both self and bus powered > devices might go to a low power state or power off state depending on the > acceptable suspend time power of the system. > In case the device experiences a power glitch or completely powers off during > suspend-resume, the device will lose its internal state and hence it'll again > need a set interface from class driver on reset resume operation. > > Issue > So far our experiments were based on a USB gadget working on cdc_eem > protocol. > We have seen that device is unable to continue the packet transfer on bulk > endpoints after the reset resume operation. > > Solution > We have added a .reset_resume function for cdc_eem protocol which sends a set > interface command on the Control endpoint. And calls the existing > usbnet_resume thereafter
You know, the USB core already issues a Set-Interface request on the control endpoint whenever a reset-resume occurs (unless the interface was using altsetting 0 beforehand). Issuing another Set-Interface shouldn't make any difference. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
