Hi Mathias, On Wed, Oct 20, 2021 at 04:05:37PM +0300, Mathias Nyman wrote: > Hi > > On 13.8.2021 22.52, Matthias Kaehlcke wrote: > > Call onboard_hub_create/destroy_pdevs() from _probe()/_remove() > > to create/destroy platform devices for onboard USB hubs that may > > be connected to the root hub of the controller. These functions > > are a NOP unless CONFIG_USB_ONBOARD_HUB=y/m. > > > > Also add a field to struct xhci_hcd to keep track of the onboard hub > > platform devices that are owned by the xHCI. > > > > Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx> > > --- > > Haven't really looked at this series until now. > > Is there any reason why the xhci platform driver was selected as > the best place to create/remove these onboard hub devices? IIRC Alan suggested to use the xhci platform driver for creating/removing the onboard hub devices when we were trying to get rid of a separate DT node on the 'platform bus', which was suitable the board for my use case. > This ties the onboard hubs to xhci, and won't work in case we have onboard > hubs connected to a ehci controllers. Right, the driver itself isn't limited to xhci. The initial idea was that support for other types of USB controllers could be added as needed (I only have a config with xhci for testing). > If separate devices for controlling onboard hub power is the right solution then > how about creating the onboard hub device in usb_add_hcd() (hcd.c), and > store it in struct usb_hcd. > > A bit like how the roothub device is created, or PHYs are tuned. Sure, that sounds feasible, even better if it's handled in a single place and different types of controllers don't have to add support separately.
