On Thu, Jan 28, 2021 at 11:52 AM Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> wrote: > > Some Qualcomm platforms require to power up an external device before > probing the PCI bus. E.g. on RB5 platform the QCA6390 WiFi/BT chip needs > to be powered up before PCIe0 bus is probed. Add a quirk to the > respective PCIe root bridge to attach to the power domain if one is > required, so that the QCA chip is started before scanning the PCIe bus. I'm lead to believe that this is also needed for QCA6174. I tried taking the driver you wrote and changing regulators to match the ones used by QCA6174, but I found that it gets probed after PCIe, which makes it get -EPROBE_DEFER when it tries to attach to the power domain, which it doesn't handle it and just proceeds to scan the bus and not find the chip as usual.