Re: [PATCH v4 4/4] dt-bindings: net: broadcom-bluetooth: Add pcm config

[Doug Anderson]

Hi,

On Tue, Nov 12, 2019 at 3:10 PM Abhishek Pandit-Subedi
<abhishekpandit@xxxxxxxxxxxx> wrote:
>
> Add documentation for pcm parameters.
>
> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
>
> ---
>
> Changes in v4:
> - Fix incorrect function name in hci_bcm
>
> Changes in v3:
> - Change disallow baudrate setting to return -EBUSY if called before
>   ready. bcm_proto is no longer modified and is back to being const.
> - Changed btbcm_set_pcm_params to btbcm_set_pcm_int_params
> - Changed brcm,sco-routing to brcm,bt-sco-routing
>
> Changes in v2:
> - Use match data to disallow baudrate setting
> - Parse pcm parameters by name instead of as a byte string
> - Fix prefix for dt-bindings commit
>
>  .../devicetree/bindings/net/broadcom-bluetooth.txt    | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/net/broadcom-bluetooth.txt b/Documentation/devicetree/bindings/net/broadcom-bluetooth.txt
> index c749dc297624..42fb2fa8143d 100644
> --- a/Documentation/devicetree/bindings/net/broadcom-bluetooth.txt
> +++ b/Documentation/devicetree/bindings/net/broadcom-bluetooth.txt
> @@ -29,6 +29,11 @@ Optional properties:
>     - "lpo": external low power 32.768 kHz clock
>   - vbat-supply: phandle to regulator supply for VBAT
>   - vddio-supply: phandle to regulator supply for VDDIO
> + - brcm,bt-sco-routing: 0-3 (PCM, Transport, Codec, I2S)
> + - brcm,pcm-interface-rate: 0-4 (128KBps, 256KBps, 512KBps, 1024KBps, 2048KBps)
> + - brcm,pcm-frame-type: 0-1 (short, long)
> + - brcm,pcm-sync-mode: 0-1 (slave, master)
> + - brcm,pcm-clock-mode: 0-1 (slave, master)

Since these are optional your patch should describe what happens if
they are not present.  I think in patch #3 of the series you guys are
discussing it, but whatever you end up with should be documented here.

That actually made me realize that this is patch #4 in the series.  To
be pedantic, bindings are supposed to be _earlier_ in the series than
the code that implements them.


>  Example:
> @@ -40,5 +45,11 @@ Example:
>         bluetooth {
>                 compatible = "brcm,bcm43438-bt";
>                 max-speed = <921600>;
> +
> +               brcm,bt-sco-routing = [01];
> +               brcm,pcm-interface-rate = [02];
> +               brcm,pcm-frame-type = [00];
> +               brcm,pcm-sync-mode = [01];
> +               brcm,pcm-clock-mode = [01];

I'm at least marginally curious why your example has a leading 0 for
all numbers.  It makes me think you intend them to be represented in
octal, though I don't know offhand if dtc uses that format for octal.
I guess it doesn't matter since all your numbers are between 0 and 5,
but it does seem strange.

-Doug