On Fri, Jun 04, 2021 at 02:40:56PM -0700, Matthias Kaehlcke wrote: > This series adds: > - the onboard_usb_hub_driver > - glue in the xhci-plat driver to create and destroy the > onboard_usb_hub platform devices if needed > - a device tree binding for the Realtek RTS5411 USB hub controller > - device tree changes that add RTS5411 entries for the QCA SC7180 > based boards trogdor and lazor > - a couple of stubs for platform device functions to avoid > unresolved symbols with certain kernel configs > > The main issue the driver addresses is that a USB hub needs to be > powered before it can be discovered. For discrete onboard hubs (an > example for such a hub is the Realtek RTS5411) this is often solved > by supplying the hub with an 'always-on' regulator, which is kind > of a hack. Some onboard hubs may require further initialization > steps, like changing the state of a GPIO or enabling a clock, which > requires even more hacks. This driver creates a platform device > representing the hub which performs the necessary initialization. > Currently it only supports switching on a single regulator, support > for multiple regulators or other actions can be added as needed. > Different initialization sequences can be supported based on the > compatible string. > > Besides performing the initialization the driver can be configured > to power the hub off during system suspend. This can help to extend > battery life on battery powered devices which have no requirements > to keep the hub powered during suspend. The driver can also be > configured to leave the hub powered when a wakeup capable USB device > is connected when suspending, and power it off otherwise. > > Changes in v11: > - support multiple onboard hubs connected to the same parent > - don't include ‘onboard_hub.h’ from the onboard hub driver There's still build warnings found by 0-day :(
