2012/3/29 Xu, Andiry <Andiry.Xu@xxxxxxx>: >> -----Original Message----- >> From: Elric Fu [mailto:elricfu1@xxxxxxxxx] >> Sent: Thursday, March 29, 2012 5:13 PM >> To: Sarah Sharp >> Cc: Xu, Andiry; Elric Fu; linux-usb@xxxxxxxxxxxxxxx >> Subject: [RFT v2] xHCI: cancel command queued in the command ring >> >> Software have to abort command ring and cancel command >> when a command is failed or hang. Otherwise, the command >> ring will hang up and can't handle the others. An example >> of a command that may hang is the Address Device Command, >> because waiting for a SET_ADDRESS request to be acknowledged >> by a USB device is outside of the xHC's ability to control. >> >> According to xHCI spec section 4.6.1.1 and section 4.6.1.2, >> after aborting a command on the command ring, xHC will >> generate a command completion event with its completion code >> set to Command Ring Stopped at least. If a command is >> currently executing at the time of aborting a command, xHC >> also generate a command completion event with its completion >> code set to Command Abort. When the command ring is stopped, >> software may remove, add, or rearrage Command Descriptors. >> >> The RFT patch is used to cancel command when the above >> situation occur. >> >> To cancel a command, software will initialize a command >> descriptor for the cancel command, and add it into a >> cancel_cmd_list of xhci. When the command ring is stopped, >> software will find the command trbs described by command >> descriptors in cancel_cmd_list and modify it to No Op >> command. If software can't find the matched trbs, we can >> think it had been finished. >> >> Signed-off-by: Elric Fu <elricfu1@xxxxxxxxx> >> Acked-by: Andiry Xu <Andiry.Xu@xxxxxxx> > > I've NOT acked this patch, just provided some comments for > the last version. Please remove this line. Is the RFT's rule different from PATCH? Or I need to add you in the release patch? Elric > > Thanks, > Andiry > > -- 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
