On Mon, Jan 13, 2025 at 09:11:33PM -0800, Bjorn Andersson wrote: > The USB IP-block found in most Qualcomm platforms is modelled in the > Linux kernel as 3 different independent device drivers, but as shown by > the already existing layering violations in the Qualcomm glue driver > they can not be operated independently. > > With the current implementation, the glue driver registers the core and > has no way to know when this is done. As a result, e.g. the suspend > callbacks needs to guard against NULL pointer dereferences when trying > to peek into the struct dwc3 found in the drvdata of the child. > > Missing from the upstream Qualcomm USB support is proper handling of > role switching, in which the glue needs to be notified upon DRD mode > changes. Several attempts has been made through the years to register > callbacks etc, but they always fall short when it comes to handling of > the core's probe deferral on resources etc. > > Furhtermore, the DeviceTree binding is a direct representation of the > Linux driver model, and doesn't necessarily describe "the USB IP-block". > > This series therefor attempts to flatten the driver split, and operate > the glue and core out of the same platform_device instance. And in order > to do this, the DeviceTree representation of the IP block is flattened. > > To avoid littering the dwc3-qcom driver with the migration code - which > we should be able to drop again in a LTS or two - this is now placed in > drivers/of/overlays. > > A patch to convert a single platform - sc8280xp - is included in the > series. The broader conversion will be submitted in a follow up series. Is it not possible to use the same overlays also fixup the .dts files at build time? Rob
