Re: [PATCH 1/2] dt-bindings: serial: Add MediaTek BTIF controller bindings

From: Rob Herring
Date: Fri Aug 11 2017 - 10:31:39 EST


On Thu, Aug 10, 2017 at 9:53 PM, Sean Wang <sean.wang@xxxxxxxxxxxx> wrote:
> On Thu, 2017-08-10 at 11:27 -0500, Rob Herring wrote:
>> On Thu, Aug 03, 2017 at 01:05:22AM +0800, sean.wang@xxxxxxxxxxxx wrote:
>> > From: Sean Wang <sean.wang@xxxxxxxxxxxx>
>> >
>> > Document the devicetree bindings for MediaTek BTIF controller
>> > which could be found on MT7622 and MT7623 SoC.
>> >
>> > Signed-off-by: Sean Wang <sean.wang@xxxxxxxxxxxx>
>> > ---
>> > .../devicetree/bindings/serial/mtk-btif.txt | 26 ++++++++++++++++++++++
>> > 1 file changed, 26 insertions(+)
>> > create mode 100644 Documentation/devicetree/bindings/serial/mtk-btif.txt
>> >
>> > diff --git a/Documentation/devicetree/bindings/serial/mtk-btif.txt b/Documentation/devicetree/bindings/serial/mtk-btif.txt
>> > new file mode 100644
>> > index 0000000..80c1f5a
>> > --- /dev/null
>> > +++ b/Documentation/devicetree/bindings/serial/mtk-btif.txt
>> > @@ -0,0 +1,26 @@
>> > +Device-Tree bindings for MediaTek BTIF controller found on those
>> > +MediaTek SoCs with Bluetooth feature
>> > +
>> > +Required properties:
>> > +- compatible: Should be one of:
>> > + - "mediatek,mt7622-btif" : for MT7622 SoC
>> > + - "mediatek,mt7623-btif" : for MT7623 SoC
>> > +- reg: The base address of the BTIF register bank;
>> > +- interrupts: A single interrupt specifier;
>> > +- clocks: list of clock specifiers, corresponding to
>> > + entries in clock-names property;
>> > +- clock-names: should contain "main" entries.
>> > +
>> > +Optional properties:
>> > +- mediatek,loopback: Boolean; if defined, indicates that BTIF controller
>> > + running on the loopback mode.
>>
>> I don't think this belongs in DT, but should be a module param or sysfs
>> control.
>>
> the loopback actually is one of hardware setups so i add it as one
> property in the dt or could you kindly guide me how to make judgment
> accurately for listing those changes as either dt or a module param?

It's just a debug mode, right? Generally a user shouldn't have to
modify the DT to change settings. Only if you wanted a given board to
always be in loopback would this make sense in DT.

>> > +
>> > +Example:
>> > +
>> > + btif: btif@1100c000 {
>>
>> bluetooth@...
>>
> btif not bluetooth, which is just the interface hardware allowing the
> the main processor communicating with the bluetooth hardware built in
> the SoC, and is really like to the uart used by legacy bluetooth.
> So i will add bluetooth as the another node.

Right, I realized that after writing this. It should be "serial@..." instead.

>
>
>> > + compatible = "mediatek,mt7623-btif";
>> > + reg = <0 0x1100c000 0 0x1000>;
>> > + interrupts = <GIC_SPI 50 IRQ_TYPE_LEVEL_LOW>;
>> > + clocks = <&pericfg CLK_PERI_BTIF>;
>> > + clock-names = "main";
>> > + };
>> > --
>> > 2.7.4
>> >
>
>