On Tue, Aug 25, 2020 at 11:46 AM Rob Herring <robh@xxxxxxxxxx> wrote: > > +Linus W > > On Tue, Aug 25, 2020 at 6:26 AM Alan Cooper <alcooperx@xxxxxxxxx> wrote: > > > > On Mon, Aug 24, 2020 at 7:30 PM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > > > On Wed, Aug 12, 2020 at 04:20:16PM -0400, Al Cooper wrote: > > > > Add DT bindings for the Broadcom USB pin map driver. This driver allows > > > > some USB input and output signals to be mapped to any GPIO instead > > > > of the normal dedicated pins to/from the XHCI controller. > > > > > > Is this a driver or h/w block because bindings are for h/w blocks? > > > > This is a hardware block. I'll remove "driver" from the description. > > Another question, this kind of looks like a pin mux controller. Is > that not a fit for this? If not, why? This driver is not doing any pin-muxing of a physical pin on the chip. Instead it's using standard gpio's, through gpiolib, and propagating the gpio state for in-coming signals to a special register that feeds into a XHCI host controller register and it's propagating the state of out-going signals from the special register fed by a XHCI controller register to a gpio. Both directions are interrupt driven and continually mirroring the state between the XHCI host controller registers and the gpios. I don't see any pinmux/pinctrl driver doing this kind of thing. Thanks Al > > > > > Signed-off-by: Al Cooper <alcooperx@xxxxxxxxx> > > > > --- > > > > .../bindings/usb/brcm,usb-pinmap.yaml | 63 +++++++++++++++++++ > > > > 1 file changed, 63 insertions(+) > > > > create mode 100644 Documentation/devicetree/bindings/usb/brcm,usb-pinmap.yaml > > > > > > > > diff --git a/Documentation/devicetree/bindings/usb/brcm,usb-pinmap.yaml b/Documentation/devicetree/bindings/usb/brcm,usb-pinmap.yaml > > > > new file mode 100644 > > > > index 000000000000..19cf6ad36373 > > > > --- /dev/null > > > > +++ b/Documentation/devicetree/bindings/usb/brcm,usb-pinmap.yaml > > > > @@ -0,0 +1,63 @@ > > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > > +%YAML 1.2 > > > > +--- > > > > +$id: http://devicetree.org/schemas/usb/brcm,usb-pinmap.yaml# > > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > > + > > > > +title: Broadcom USB pin map Controller Device Tree Bindings > > > > + > > > > +maintainers: > > > > + - Al Cooper <alcooperx@xxxxxxxxx> > > > > + > > > > +properties: > > > > + compatible: > > > > + items: > > > > + - const: brcm,usb-pinmap > > > > > > 2 space indentation please. > > > > Fixed. > > > > > > > > > + > > > > + reg: > > > > + maxItems: 1 > > > > + > > > > + interrupts: > > > > + maxItems: 1 > > > > + description: Must be defined if any out-gpios are specified. > > > > > > 'dependencies' can express this in schema. > > > > Okay. > > > > > > > > > + > > > > + in-gpios: > > > > + description: Array of one or more GPIO pins used for input signals. > > > > > > You need to define how many GPIOs are valid. > > > > I tried to avoid doing this because there is a possibility that future > > chips will have a few more signals added and the driver was written so > > new signals can be added entirely in device tree without any changes > > to the driver. If this is unacceptable, I can add the current max in > > and out valid gpios. > > A 'should be enough for a while' value is fine. The driver doesn't > have to have a max. I'd expect the binding to be updated for new SoCs > anyways. > > > > > > > > + > > > > + in-names: > > > > + description: Array of input signal names, one per gpio in in-gpios. > > > > > > No, this isn't how we name GPIOs. The part before '-gpios' is how. > > > > This is the meant to be a description of how each gpio is being used > > to help with error messages in the driver. > > What if I use "brcmstb,in-functions" instead? > > 'brcmstb' is not a vendor. But brcm,in-functions is fine. > > > > > + > > > > + in-masks: > > > > + description: Array of enable and mask pairs, one per gpio in-gpios. > > > > > > Needs a vendor prefix. > > > > I'll change it to "brcmstb,in-masks" > > > > > > > > > + > > > > + out-gpios: > > > > + description: Array of one or more GPIO pins used for output signals. > > > > + > > > > + out-names: > > > > + description: Array of output signal names, one per gpio in out-gpios. > > > > + > > > > + out-masks: > > > > + description: Array of enable, value, changed and clear masks, one > > > > + per gpio in out-gpios. > > > > + > > > > +required: > > > > + - compatible > > > > + - reg > > > > + > > > > +additionalProperties: false > > > > + > > > > +examples: > > > > + - | > > > > + usb_pinmap: usb-pinmap@22000d0 { > > > > + compatible = "brcm,usb-pinmap"; > > > > + reg = <0x22000d0 0x4>; > > > > + in-gpios = <&gpio 18 0>, <&gpio 19 0>; > > > > + in-names = "VBUS", "PWRFLT"; > > > > + in-masks = <0x8000 0x40000 0x10000 0x80000>; > > > > + out-gpios = <&gpio 20 0>; > > > > + out-names = "PWRON"; > > > > + out-masks = <0x20000 0x800000 0x400000 0x200000>; > > > > + interrupts = <0x0 0xb2 0x4>; > > > > + }; > > > > + > > > > +... > > > > -- > > > > 2.17.1 > > > >
