Re: Audio sound card name [was [PATCH 4/7] arm64: dts: allwinner: a64: Add HDMI audio]

From: Robin Murphy <robin.murphy@arm.com>
To: "Clément Péron" <peron.clem@gmail.com>,
	"Mark Brown" <broonie@kernel.org>
Cc: devicetree <devicetree@vger.kernel.org>,
	Linux-ALSA <alsa-devel@alsa-project.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	linux-sunxi <linux-sunxi@googlegroups.com>,
	Jernej Skrabec <jernej.skrabec@siol.net>,
	Takashi Iwai <tiwai@suse.com>, Jaroslav Kysela <perex@perex.cz>,
	Marcus Cooper <codekipper@gmail.com>,
	Chen-Yu Tsai <wens@csie.org>, Rob Herring <robh+dt@kernel.org>,
	Maxime Ripard <maxime@cerno.tech>,
	linux-arm-kernel <linux-arm-kernel@lists.infradead.org>
Subject: Re: Audio sound card name [was [PATCH 4/7] arm64: dts: allwinner: a64: Add HDMI audio]
Date: Tue, 28 Apr 2020 18:11:26 +0100	[thread overview]
Message-ID: <031ee5d3-8a30-82ee-76db-c0e8a1073046@arm.com> (raw)
In-Reply-To: <CAJiuCccFFUJJzXwygLQbDK4fGJ61p72Hv7vj3WVP-=z=J1Yj0Q@mail.gmail.com>

On 2020-04-28 5:49 pm, Clément Péron wrote:
> Hi Mark, Rob,
> 
> On Tue, 28 Apr 2020 at 18:04, Maxime Ripard <maxime@cerno.tech> wrote:
>>
>> On Tue, Apr 28, 2020 at 10:54:00AM +0200, Clément Péron wrote:
>>> Hi Maxime,
>>>
>>> On Tue, 28 Apr 2020 at 10:00, Maxime Ripard <maxime@cerno.tech> wrote:
>>>>
>>>> On Sun, Apr 26, 2020 at 02:04:39PM +0200, Clément Péron wrote:
>>>>> From: Marcus Cooper <codekipper@gmail.com>
>>>>>
>>>>> Add a simple-soundcard to link audio between HDMI and I2S.
>>>>>
>>>>> Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
>>>>> Signed-off-by: Marcus Cooper <codekipper@gmail.com>
>>>>> Signed-off-by: Clément Péron <peron.clem@gmail.com>
>>>>> ---
>>>>>   arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 21 +++++++++++++++++++
>>>>>   1 file changed, 21 insertions(+)
>>>>>
>>>>> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
>>>>> index e56e1e3d4b73..08ab6b5e72a5 100644
>>>>> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
>>>>> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
>>>>> @@ -102,6 +102,25 @@
>>>>>                status = "disabled";
>>>>>        };
>>>>>
>>>>> +     hdmi_sound: hdmi-sound {
>>>>> +             compatible = "simple-audio-card";
>>>>> +             simple-audio-card,format = "i2s";
>>>>> +             simple-audio-card,name = "allwinner,hdmi";
>>>>
>>>> I'm not sure what the usual card name should be like though. I would assume that
>>>> this should be something specific enough so that you're able to differentiate
>>>> between boards / SoC so that the userspace can choose a different configuration
>>>> based on it?
>>>
>>> I really don't know what we should use here,
>>> I just have a look at other SoC:
>>> rk3328: "HDMI"
>>> rk3399: "hdmi-sound"
>>> r8a774c0-cat874: "CAT874 HDMI sound"
>>>
>>> But maybe it's time to introduce proper name:
>>> What about :
>>> pat
>>> sun50i-h6-hdmi
>>
>> It's pretty much what we've been using for the other sound cards we have, so it
>> makes sense to me.
> 
> I have a question regarding the simple-audio-card,name.
> In this patch, I would like to introduce a simple-audio-card for the
> Allwinner A64 HDMI.
> 
> What should be the preferred name for this sound card?
> "sun50i-a64-hdmi" ? "allwinner, sun50i-a64-hdmi" ?

I can at least speak for RK3328, and the reasoning there was that as the 
user looking at what `aplay -l` says, I don't give a hoot about what the 
SoC may be called, I see two cards and I want to know, with the least 
amount of uncertainty, which one will make the sound come out of the 
port that's labelled "HDMI" on the box ;)

Robin.