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Date:   Tue, 25 May 2021 10:35:14 +0200
Message-ID: <s5hzgwjcit9.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Maxime Ripard <maxime@cerno.tech>
Cc:     Mark Brown <broonie@kernel.org>, Takashi Iwai <tiwai@suse.com>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Jaroslav Kysela <perex@perex.cz>,
        dri-devel@lists.freedesktop.org,
        Daniel Vetter <daniel.vetter@intel.com>,
        David Airlie <airlied@linux.ie>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        devicetree@vger.kernel.org, alsa-devel@alsa-project.org,
        Dom Cobley <dom@raspberrypi.com>,
        Tim Gover <tim.gover@raspberrypi.com>,
        Dave Stevenson <dave.stevenson@raspberrypi.com>,
        linux-kernel@vger.kernel.org, Eric Anholt <eric@anholt.net>,
        Rob Herring <robh+dt@kernel.org>,
        bcm-kernel-feedback-list@broadcom.com,
        Nicolas Saenz Julienne <nsaenzjulienne@kernel.org>,
        Daniel Vetter <daniel@ffwll.ch>,
        Phil Elwell <phil@raspberrypi.com>,
        linux-arm-kernel@lists.infradead.org,
        linux-rpi-kernel@lists.infradead.org
Subject: Re: [PATCH 00/11] drm/vc4: hdmi: Enable Channel Mapping, IEC958, HBR Passthrough using hdmi-codec
In-Reply-To: <20210524133904.kgkh6xd3m5c2j3xa@gilmour>
References: <20210507140334.204865-1-maxime@cerno.tech>
        <20210524133904.kgkh6xd3m5c2j3xa@gilmour>
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On Mon, 24 May 2021 15:39:04 +0200,
Maxime Ripard wrote:
> 
> Hi,
> 
> On Fri, May 07, 2021 at 04:03:23PM +0200, Maxime Ripard wrote:
> > Hi,
> > 
> > hdmi-codec allows to have a lot of HDMI-audio related infrastructure in place,
> > it's missing a few controls to be able to provide HBR passthrough. This series
> > adds more infrastructure for the drivers, and leverages it in the vc4 HDMI
> > controller driver.
> > 
> > One thing that felt a bit weird is that even though
> > https://www.kernel.org/doc/html/latest/sound/kernel-api/writing-an-alsa-driver.html#iec958-s-pdif
> > mentions that the iec958 mask control should be a mixer control and the
> > default control should be a PCM one, it feels a bit weird to have two different
> > control type for two controls so similar, and other drivers are pretty
> > inconsistent with this. Should we update the documentation?
> 
> Any comments on this series?

A patch for updating the documentation is welcome.
Currently, as de facto standard, we allow both MIXER and PCM ifaces
for all IEC958-related controls, and it's unlikely that we would
change that in future.


thanks,

Takashi