On Thu, Mar 24, 2022 at 12:53:08PM +0100, Krzysztof Kozlowski wrote: > On 24/03/2022 12:40, Aswath Govindraju wrote: > > Hi Krzysztof, > > > > On 24/03/22 16:37, Krzysztof Kozlowski wrote: > >> On 24/03/2022 08:34, Aswath Govindraju wrote: > >>> Add bindings for the TI's AM62 wrapper module for the Synopsys USBSS-DRD > >>> controller. > >>> > >>> Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx> > >>> --- > >>> > >>> Changes since v1: > >>> - made correction in grammer of clocks property description > >>> and added maxItems in the interrupts property based on comments > >>> received from Roger > >>> - corrected the title, fixed the description of > >>> ti,syscon-phy-pll-refclk, added pattern properties and child node > >>> in the example based on the comments from Krzysztof. > >>> > >>> .../devicetree/bindings/usb/ti,am62-usb.yaml | 117 ++++++++++++++++++ > >>> 1 file changed, 117 insertions(+) > >>> create mode 100644 Documentation/devicetree/bindings/usb/ti,am62-usb.yaml > >>> > >>> diff --git a/Documentation/devicetree/bindings/usb/ti,am62-usb.yaml b/Documentation/devicetree/bindings/usb/ti,am62-usb.yaml > >>> new file mode 100644 > >>> index 000000000000..452bfdc6fb09 > >>> --- /dev/null > >>> +++ b/Documentation/devicetree/bindings/usb/ti,am62-usb.yaml > >>> @@ -0,0 +1,117 @@ > >>> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause > >>> +%YAML 1.2 > >>> +--- > >>> +$id: http://devicetree.org/schemas/usb/ti,am62-usb.yaml# > >>> +$schema: http://devicetree.org/meta-schemas/core.yaml# > >>> + > >>> +title: TI's AM62 wrapper module for the Synopsys USBSS-DRD controller > >>> + > >>> +maintainers: > >>> + - Aswath Govindraju <a-govindraju@xxxxxx> > >>> + > >>> +properties: > >>> + compatible: > >>> + const: ti,am62-usb > >>> + > >>> + reg: > >>> + maxItems: 1 > >>> + > >>> + ranges: true > >>> + > >>> + power-domains: > >>> + description: > >>> + PM domain provider node and an args specifier containing > >>> + the USB ISO device id value. See, > >>> + Documentation/devicetree/bindings/soc/ti/sci-pm-domain.yaml > >>> + maxItems: 1 > >>> + > >>> + clocks: > >>> + description: Clock phandle to usb2_refclk > >>> + maxItems: 1 > >>> + > >>> + clock-names: > >>> + items: > >>> + - const: ref > >>> + > >>> + id-gpio: > >>> + description: > >>> + GPIO to be used as ID pin > >>> + maxItems: 1 > >> > >> I have doubts about this. If you USB controller handles the ID pin, then > >> probably this should be moved to usb-connector.yaml. I did not see > >> id-gpio in any other USB controller blocks. > >> > > > > Yes, the USB wrapper handles the ID pin operation only. It also reads > > the status of VBUS by reading a register from its MMR and not using a > > gpio. After evaluating the role the based on the states if id pin and > > VBUS, this role is communicated to the dwc3 core driver using extcon. > > There is no way for the dwc3 driver to detect the role on its own. > > > > > > The usb-connector(drivers/usb/common/usb-conn-gpio.c) driver, seems to > > be implemented for driving the VBUS, based on ID and VBUS pin status. > > However, in case of the above implementation we need to communicate the > > detected role to the dwc3 core driver. Also, the wrapper does not > > control VBUS but it is the dwc3 core driver that drives the VBUS. > > Therefore, I think the usb-connector implementation cannot be used here. > > I don't think about usb-conn-gpio.c but using the binding generic > binding for usb-X-connector and define a connector with ID. > > Actually Rob could help here. > > Rob, > Should the id-gpio be modeled as a property in this glue/wrapper driver > or rather as part of usb-connector child node? That's a simple question. Where does the ID GPIO signal go to? The connector, so it goes in the connector node. If we have a driver for the usb-connector node, that's news to me. Not that we couldn't, but that has nothing to do with designing the binding. Rob
