This series is the outcome of a discussion with Felipe Balbi, see [0] and [1]. The quick-summary of this is: - dwc3 already takes one USB2 and one USB3 PHY and initializes these correct - some other HCI platform drivers (like ehci-platform.c, xhci-mtk.c and ohci-platform.c) do not have a limitation on the number of PHYs - they support one PHY per actual host port - Amlogic Meson GXL and GXM SoCs come with a dwc3 IP block which has two or three USB2 ports enabled on the internal root-hub. The SoCs also provide separate USB2 PHYs, one per port. All USB2 PHYs (which are internally "connected" to the dwc3 roothub) need to be powered on, otherwise USB devices cannot be enumerated (even if just one PHY is disabled and if the device is plugged into another, enabled port) In my first attempt to get USB supported on the GXL and GXM SoCs I tried to work-around the problem that I could not pass multiple PHYs to the dwc3 controller. This was rejected by Rob Herring (which was definitely the thing to do in my opinion), see [2] This series adds a new "platform-roothub". This can be configured through devicetree by passing a child-node with "reg = <0>" to the USB controller. Additionally there has to be a child-node for each port on the root-hub. Each of the child-nodes takes a "phys" and "phy-names" property. This allows modeling the root-hub in devicetree similar to the USB device binding (documented in devicetree/bindings/usb/usb-device.txt) This avoids and backwards-compatibility problems (which was a concern regardless of the solution, see [3]) since the binding for the root-hub was previously not specified (and we're not using the "phys" property of the controller, which might have served different purposes before, depending on the drivers). Additionally this integrates the new platform-roothub into xhci-plat.c which automatically enables it for the dwc3 driver (in host-mode). [0] http://lists.infradead.org/pipermail/linux-amlogic/2017-January/001945.html [1] http://lists.infradead.org/pipermail/linux-amlogic/2017-January/001947.html [2] http://lists.infradead.org/pipermail/linux-amlogic/2016-November/001818.html [3] http://lists.infradead.org/pipermail/linux-amlogic/2017-January/001948.html Martin Blumenstingl (2): usb: host: add a generic platform USB roothub driver usb: host: xhci: plat: integrate the platform-roothub .../devicetree/bindings/usb/usb-roothub.txt | 41 ++++++ Documentation/devicetree/bindings/usb/usb-xhci.txt | 7 + drivers/usb/host/Kconfig | 4 + drivers/usb/host/Makefile | 2 + drivers/usb/host/platform-roothub.c | 146 +++++++++++++++++++++ drivers/usb/host/platform-roothub.h | 14 ++ drivers/usb/host/xhci-plat.c | 37 +++++- drivers/usb/host/xhci.h | 3 + 8 files changed, 251 insertions(+), 3 deletions(-) create mode 100644 Documentation/devicetree/bindings/usb/usb-roothub.txt create mode 100644 drivers/usb/host/platform-roothub.c create mode 100644 drivers/usb/host/platform-roothub.h -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
