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

From: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
To: Matthias Kaehlcke <mka@chromium.org>
Cc: Marcel Holtmann <marcel@holtmann.org>,
	Johan Hedberg <johan.hedberg@gmail.com>,
	Rob Herring <robh+dt@kernel.org>,
	linux-bluetooth@vger.kernel.org,
	Douglas Anderson <dianders@chromium.org>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
	<devicetree@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	netdev@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
	Ondrej Jirman <megous@megous.com>,
	Mark Rutland <mark.rutland@arm.com>, Chen-Yu Tsai <wens@csie.org>
Subject: Re: [PATCH v4 4/4] dt-bindings: net: broadcom-bluetooth: Add pcm config
Date: Thu, 14 Nov 2019 11:21:42 -0800	[thread overview]
Message-ID: <CANFp7mXfhs3mw_QuVQHcQwkz8+4DpJ8SMbTiwS=7fo5kXGrBQQ@mail.gmail.com> (raw)
In-Reply-To: <20191114175836.GI27773@google.com>

On Thu, Nov 14, 2019 at 9:58 AM Matthias Kaehlcke <mka@chromium.org> wrote:
>
> On Wed, Nov 13, 2019 at 01:21:06AM +0100, Marcel Holtmann wrote:
> > Hi Abhishek,
> >
> > > Add documentation for pcm parameters.
> > >
> > > Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> > >
> > > ---
> > >
> > > 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)
> >
> > I think that all of them need to start with brcm,bt- prefix since it is rather Bluetooth specific.
> >
> > >
> > >
> > > 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];
> > >        };
> >
> > My personal taste would be to add a comment after each entry that gives the human readable setting.
>
> I'd suggest to define constants in include/dt-bindings/bluetooth/brcm.h
> and use them instead of literals, with this we wouldn't rely on (optional)
> comments to make the configuration human readable.

:+1: Sounds like a good idea; expect it in next patch revision