• Douglas Anderson's avatar
    usb: dwc2: optionally assert phy reset when waking up · c40cf770
    Douglas Anderson authored
    On the rk3288 USB host-only port (the one that's not the OTG-enabled
    port) the PHY can get into a bad state when a wakeup is asserted (not
    just a wakeup from full system suspend but also a wakeup from
    We can get the PHY out of its bad state by asserting its "port reset",
    but unfortunately that seems to assert a reset onto the USB bus so it
    could confuse things if we don't actually deenumerate / reenumerate the
    We can also get the PHY out of its bad state by fully resetting it using
    the reset from the CRU (clock reset unit), which does a more full
    reset.  The CRU-based reset appears to actually cause devices on the bus
    to be removed and reinserted, which fixes the problem (albeit in a hacky
    It's unfortunate that we need to do a full re-enumeration of devices at
    wakeup time, but this is better than alternative of letting the bus get
    Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
    Signed-off-by: default avatarYunzhi Li <lyz@rock-chips.com>
    Signed-off-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
core_intr.c 23.2 KB