From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [PATCH v8 4/9] mfd: Add binding document for NVIDIA Tegra XUSB Date: Thu, 14 May 2015 08:32:33 +0100 Message-ID: <55544F91.4060402@nvidia.com> References: <1430761002-9327-1-git-send-email-abrestic@chromium.org> <1430761002-9327-5-git-send-email-abrestic@chromium.org> <20150513143954.GA3394@x1> <20150513165014.GC19543@x1> <20150514072954.GD20358@x1> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150514072954.GD20358@x1> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Lee Jones , Andrew Bresticker Cc: Stephen Warren , Thierry Reding , Alexandre Courbot , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Samuel Ortiz List-Id: devicetree@vger.kernel.org On 14/05/15 08:29, Lee Jones wrote: > On Wed, 13 May 2015, Andrew Bresticker wrote: > >> On Wed, May 13, 2015 at 9:50 AM, Lee Jones wrote: >>> On Wed, 13 May 2015, Andrew Bresticker wrote: >>> >>>> Lee, >>>> >>>> On Wed, May 13, 2015 at 7:39 AM, Lee Jones 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 >>>>>> Cc: Rob Herring >>>>>> Cc: Pawel Moll >>>>>> Cc: Mark Rutland >>>>>> Cc: Ian Campbell >>>>>> Cc: Kumar Gala >>>>>> Cc: Samuel Ortiz >>>>>> Cc: Lee Jones >>>>>> --- >>>>>> 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,-xusb", "nvidia,tegra124-xusb"' >>>>>> + where 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? >> >> What do you mean? That's what the MFD is doing now by setting up an >> MMIO regmap to be shared between the two devices. > > I mean, can you share the documentation with me. :) You can download the documentation from here [1]. See chapter 19 USB complex. However, I will warn you that unfortunately, you need to sign up for an account :-( Cheers Jon [1] https://developer.nvidia.com/tegra-k1-technical-reference-manual