Re: [PATCH v8 4/9] mfd: Add binding document for NVIDIA Tegra XUSB

[Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>]

On Wed, 13 May 2015, Andrew Bresticker wrote:

> Lee,
> 
> On Wed, May 13, 2015 at 7:39 AM, Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> wrote:
> > On Mon, 04 May 2015, Andrew Bresticker wrote:
> >
> >> Add a binding document for the XUSB host complex on NVIDIA Tegra124
> >> and later SoCs.  The XUSB host complex includes a mailbox for
> >> communication with the XUSB micro-controller and an xHCI host-controller.
> >>
> >> Signed-off-by: Andrew Bresticker <abrestic-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
> >> Cc: Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> >> Cc: Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>
> >> Cc: Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>
> >> Cc: Ian Campbell <ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org>
> >> Cc: Kumar Gala <galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>
> >> Cc: Samuel Ortiz <sameo-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> >> Cc: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> >> ---
> >> Changes from v7:
> >>  - Move non-shared resources into child nodes.
> >> New for v7.
> >> ---
> >>  .../bindings/mfd/nvidia,tegra124-xusb.txt          | 37 ++++++++++++++++++++++
> >>  1 file changed, 37 insertions(+)
> >>  create mode 100644 Documentation/devicetree/bindings/mfd/nvidia,tegra124-xusb.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/mfd/nvidia,tegra124-xusb.txt b/Documentation/devicetree/bindings/mfd/nvidia,tegra124-xusb.txt
> >> new file mode 100644
> >> index 0000000..bc50110
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/mfd/nvidia,tegra124-xusb.txt
> >> @@ -0,0 +1,37 @@
> >> +NVIDIA Tegra XUSB host copmlex
> >> +==============================
> >> +
> >> +The XUSB host complex on Tegra124 and later SoCs contains an xHCI host
> >> +controller and a mailbox for communication with the XUSB micro-controller.
> >> +
> >> +Required properties:
> >> +--------------------
> >> + - compatible: For Tegra124, must contain "nvidia,tegra124-xusb".
> >> +   Otherwise, must contain '"nvidia,<chip>-xusb", "nvidia,tegra124-xusb"'
> >> +   where <chip> is tegra132.
> >> + - reg: Must contain the base and length of the XUSB FPCI registers.
> >> + - ranges: Bus address mapping for the XUSB block.  Can be empty since the
> >> +   mapping is 1:1.
> >> + - #address-cells: Must be 2.
> >> + - #size-cells: Must be 2.
> >> +
> >> +Example:
> >> +--------
> >> +     usb@0,70098000 {
> >> +             compatible = "nvidia,tegra124-xusb";
> >> +             reg = <0x0 0x70098000 0x0 0x1000>;
> >> +             ranges;
> >> +
> >> +             #address-cells = <2>;
> >> +             #size-cells = <2>;
> >> +
> >> +             usb-host@0,70090000 {
> >> +                     compatible = "nvidia,tegra124-xhci";
> >> +                     ...
> >> +             };
> >> +
> >> +             mailbox {
> >> +                     compatible = "nvidia,tegra124-xusb-mbox";
> >> +                     ...
> >> +             };
> >
> > This doesn't appear to be a proper MFD.  I would have the USB and
> > Mailbox devices probe seperately and use a phandle to point the USB
> > device to its Mailbox.
> >
> > usb@xyz {
> >         mboxes = <&xusb-mailbox, [chan]>;
> > };
> 
> Then what will set up the shared regmap?  The point of using an MFD
> here was to share a register set with both the mailbox and xHCI
> drivers and avoid having to map the same register set twice in two
> separate drivers.

Can you share the mapping please?

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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