> On 2019-05-13 11:00, Peter Chen wrote: > >> 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? > > I don't mind fixing it in ehci-exynos, but frankly so far I have no idea how to do it. > The problem is that newly created USB devices get of-node pointer pointing to a > node which if not intended for them. How this can be fixed in ehci-exynos? > Can't be workaround by setting of_node as NULL for EHCI controller or for PHY node at exynos_ehci_get_phy? Peter