• Prashanth K's avatar
    usb: dwc3: Wait unconditionally after issuing EndXfer command · 1d26ba09
    Prashanth K authored
    Currently all controller IP/revisions except DWC3_usb3 >= 310a
    wait 1ms unconditionally for ENDXFER completion when IOC is not
    set. This is because DWC_usb3 controller revisions >= 3.10a
    supports GUCTL2[14: Rst_actbitlater] bit which allows polling
    CMDACT bit to know whether ENDXFER command is completed.
    
    Consider a case where an IN request was queued, and parallelly
    soft_disconnect was called (due to ffs_epfile_release). This
    eventually calls stop_active_transfer with IOC cleared, hence
    send_gadget_ep_cmd() skips waiting for CMDACT cleared during
    EndXfer. For DWC3 controllers with revisions >= 310a, we don't
    forcefully wait for 1ms either, and we proceed by unmapping the
    requests. If ENDXFER didn't complete by this time, it leads to
    SMMU faults since the controller would still be accessing those
    requests.
    
    Fix this by ensuring ENDXFER completion by adding 1ms delay in
    __dwc3_stop_active_transfer() unconditionally.
    
    Cc: stable@vger.kernel.org
    Fixes: b353eb6d ("usb: dwc3: gadget: Skip waiting for CMDACT cleared during endxfer")
    Signed-off-by: default avatarPrashanth K <quic_prashk@quicinc.com>
    Acked-by: default avatarThinh Nguyen <Thinh.Nguyen@synopsys.com>
    Link: https://lore.kernel.org/r/20240502044103.1066350-1-quic_prashk@quicinc.comSigned-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    1d26ba09
gadget.c 124 KB