Re: [PATCH v1] dt-bindings: dsp: mediatek: add mt8186 dsp document

From: Tinghan Shen
Date: Thu Jun 02 2022 - 06:20:04 EST


Hi Krzysztof,

On Thu, 2022-06-02 at 09:40 +0200, Krzysztof Kozlowski wrote:
> On 02/06/2022 08:44, Tinghan Shen wrote:
> > > > + mbox-names:
> > > > + items:
> > > > + - const: mbox0
> > > > + - const: mbox1
> > >
> > > These should be rather some meaningful names, e.g. "rx" and "tx".
> >
> > The mbox name has to align with the adsp ipc driver.
> > The adsp ipc driver is using 'mbox%d' for mailbox channels.
> >
> >
> >
https://urldefense.com/v3/__https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/commit/?id=9db69df4bdd37eb1f65b6931ee067fb15b9a4d5c__;!!CTRNKA9wMg0ARbw!1TmempNkQhC5QuLBhyfWo_AC97MoLuWipsGV-LPaW9RKNPheU7Bgc-eboNi1JA1nC5I$
> >
> >
> > chan_name = kasprintf(GFP_KERNEL, "mbox%d", i);
> >
> > /* ...snip... */
> >
> > adsp_chan->ch = mbox_request_channel_byname(cl, chan_name);
> >
> > Is it ok to continue using these names?
>
> It is a bit confusing... how did that driver got merged recently without
> bindings? Why bindings are separate?
>
> The bindings always come together in one patchset with the driver
> implementing them. Bindings are though a separate patch, yet still
> followed by the driver which uses them.
>
> I do not see any compatibles in that driver, which suggests there is no
> other binding using it. If that's correct, then you need to change the
> driver.
>

The mtk-adsp-ipc driver's sole function is to encapsulate the operations
of mailbox framework from adsp ipc users. The mtk-adsp-ipc is not defined
in the dts file and we don't need it to be defined. The creation of mtk-adsp-ipc
device is requested by adsp ipc users via the use of 'platform_device_register_data'[1].

the driver implemented the mailbox framework is 'mtk-adsp-mailbox'[2]. it has
corresponding hardwares and a yaml file[3] to describe it.

I'll send a patch to change the mbox name at next version.
It's better to have some meaningful names as you said.

[1]
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/commit/?id=e0100bfd383c7d994d2e957e85ca56a5fe5a3f43
[2]
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/commit/?id=af2dfa96c52d042df5deb29fb6e32d3ff4d76a61
[3]
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/commit/?id=afa092e1e8824363d3174fef329c034445c111d5

Thanks,
TingHan