usb: dwc2: optionally assert phy reset when waking up
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 autosuspend). 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 device. 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 way). 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 wedged. Signed-off-by:Douglas Anderson <dianders@chromium.org> Signed-off-by:
Yunzhi Li <lyz@rock-chips.com> Signed-off-by:
Felipe Balbi <felipe.balbi@linux.intel.com>
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- drivers/usb/dwc2/core.h 8 additions, 0 deletionsdrivers/usb/dwc2/core.h
- drivers/usb/dwc2/core_intr.c 12 additions, 0 deletionsdrivers/usb/dwc2/core_intr.c
- drivers/usb/dwc2/hcd.c 15 additions, 3 deletionsdrivers/usb/dwc2/hcd.c
- drivers/usb/dwc2/platform.c 9 additions, 0 deletionsdrivers/usb/dwc2/platform.c
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