RE: [PATCH v3] usb: core: verify devicetree nodes for USB devices

From: Peter Chen
Date: Mon May 13 2019 - 05:02:17 EST



>
> On 2019-05-10 05:10, Peter Chen wrote:
> >
> >> Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> writes:
> >>> Commit 69bec7259853 ("USB: core: let USB device know device node")
> >>> added support for attaching devicetree node for USB devices. The
> >>> mentioned commit however identifies the given USB device node only by the
> 'reg'
> >>> property in the host controller children nodes. The USB device node
> >>> however also has to have a 'compatible' property as described in
> >>> Documentation/devicetree/bindings/usb/usb-device.txt. Lack for the
> >>> 'compatible' property check might result in assigning a devicetree
> >>> node, which is not intended to be the proper node for the given USB device.
> >>>
> >>> This is important especially when USB host controller has
> >>> child-nodes for other purposes. For example, Exynos EHCI and OHCI
> >>> drivers already define child-nodes for each physical root hub port
> >>> and assigns respective PHY controller and parameters for them. Those
> >>> binding predates support for USB devicetree nodes.
> >>>
> >>> Checking for the proper compatibility string allows to mitigate the
> >>> conflict between USB device devicetree nodes and the bindings for
> >>> USB controllers with child nodes. It also fixes the side-effect of
> >>> the other commits, like 01fdf179f4b0 ("usb: core: skip interfaces
> >>> disabled in devicetree"), which incorrectly disables some devices on
> >>> Exynos based boards.
> > Hi Marek,
> >
> > The purpose of your patch is do not set of_node for device under USB controller,
> right?
>
> Right.
>

Do you mind doing it at function exynos_ehci_get_phy of ehci-exynos.c?

Peter