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? Best regards, Krzysztof
