Currently for all dwc3 devices, runtime is forbidden in kernel code. Although it can be configured from userspace, qualcomm devices using role switching with dr_mode "otg" would need to modify glue specific qscratch registers without which connection done/ disconnect events wouldn't be generated in device mode thus blocking suspend entry. Also when in host mode, xhci and roothubs needs to be configured to use_autosuspend accrordingly. More information regarding disconnect event generation on QC targets is in [1]. The series introduces vendor hooks for passing on notifications from core to glue layers. Since these hooks are to be registered by glue to core, glue needs to have some sort of indication that core probe hasn't been deferred or core probe hasn't failed. So this series banks upon Bjorn's flattened device tree implementation [2] for dwc3 core and dwc3-qcom. Since these patches ensure that we use core layer as a library and probe is invoked in a controlled fashion from qcom glue layer, we can register vendor hooks in this probe call. While in host mode, usb-core notifiers have been utilised to ensure we use_autosuspend for connected devices and roothubs. [1]: https://lore.kernel.org/all/af60c05b-4a0f-51b8-486a-1fc601602515@xxxxxxxxxxx/ [2]: https://lore.kernel.org/all/20231016-dwc3-refactor-v1-0-ab4a84165470@xxxxxxxxxxx/ Tests done: 1. Enumeration in device mode: After creating symlinks to ffs.adb and writing to UDC node, ADB is up and working in a stable way. 2. When none is written to UDC, device enters suspend. 3. When cable is removed, cable disconnect notification comes and when qscratch registers are cleared properly, it is generating disconnect event 4. Device enters suspend upon removing cable (host and device mode) 5. In host mode, when autosuspend and wakeup are enabled from userspace via the following commands, device enters runtime suspend: echo enabled > /sys/bus/platform/devices/xhci-hcd.0.auto/power/wakeup echo auto > /sys/bus/platform/devices/xhci-hcd.0.auto/power/control echo 5000 > /sys/bus/platform/devices/xhci-hcd.0.auto/usb1/1-1/power/autosuspend_delay_ms echo enabled > /sys/bus/platform/devices/xhci-hcd.0.auto/usb1/1-1/power/wakeup echo auto > /sys/bus/platform/devices/xhci-hcd.0.auto/usb1/1-1/power/control 6. Upon removing cable in host mode, setmode brings back usb to device mode (which is default setting), it enters suspend as cable is still disconnected 7. When in host mode, if we enter runtime suspend with wakeup enabled, clicking on buttons of headset are resuming the controller. Issues still present: During bootup if UDC is not written before dwc3 is suspended, then device enters suspend and although writing to UDC is resuming the device and setting run stop, controller is not generating events. At this stage if a simple plug-in/plug-out is done, everything works fine. Krishna Kurapati (8): dt-bindings: usb: qcom,dwc3: Add bindings to enable runtime usb: dwc3: core: Register vendor hooks for dwc3-qcom usb: dwc3: qcom: Enable autosuspend for host mode clk: qcom: gcc-sm8450: Keep usb30 prim gdsc on during runtime suspend arm64: dts: qcom: Flatten sm8450 usb device node arm: dts: qcom: Add pmic glink support for sm8450-qrd arm: dts: qcom: Enable runtime for SM8450 QRD usb: dwc3: core: Skip set_mode notification if cable is disconnected .../devicetree/bindings/usb/qcom,dwc3.yaml | 5 + arch/arm64/boot/dts/qcom/sm8450-hdk.dts | 3 - arch/arm64/boot/dts/qcom/sm8450-qrd.dts | 48 ++++++- .../dts/qcom/sm8450-sony-xperia-nagara.dtsi | 3 - arch/arm64/boot/dts/qcom/sm8450.dtsi | 44 +++---- drivers/clk/qcom/gcc-sm8450.c | 1 + drivers/usb/dwc3/core.c | 19 ++- drivers/usb/dwc3/core.h | 50 ++++++- drivers/usb/dwc3/drd.c | 13 ++ drivers/usb/dwc3/dwc3-qcom.c | 122 +++++++++++++++++- 10 files changed, 271 insertions(+), 37 deletions(-) -- 2.42.0
