linux-kernel - Re: [alsa-devel] [PATCH v2 1/3] dt-bindings: ASoC: Add TDA7802 amplifier

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <16a99e45-fd5a-2878-acf9-63518f9ca527@codethink.co.uk>
Date:   Tue, 30 Jul 2019 15:12:21 +0100
From:   Thomas Preston <thomas.preston@...ethink.co.uk>
To:     Marco Felsch <m.felsch@...gutronix.de>,
        Charles Keepax <ckeepax@...nsource.cirrus.com>
Cc:     Mark Rutland <mark.rutland@....com>, devicetree@...r.kernel.org,
        alsa-devel@...a-project.org, Rob Duncan <rduncan@...la.com>,
        Kuninori Morimoto <kuninori.morimoto.gx@...esas.com>,
        Kirill Marinushkin <kmarinushkin@...dec.tech>,
        linux-kernel@...r.kernel.org, Mark Brown <broonie@...nel.org>,
        Takashi Iwai <tiwai@...e.com>,
        Liam Girdwood <lgirdwood@...il.com>,
        Annaliese McDermond <nh6z@...z.net>,
        Paul Cercueil <paul@...pouillou.net>,
        Vinod Koul <vkoul@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Srinivas Kandagatla <srinivas.kandagatla@...aro.org>,
        Nate Case <ncase@...la.com>,
        Cheng-Yi Chiang <cychiang@...omium.org>,
        Patrick Glaser <pglaser@...la.com>,
        Jerome Brunet <jbrunet@...libre.com>
Subject: Re: [alsa-devel] [PATCH v2 1/3] dt-bindings: ASoC: Add TDA7802
 amplifier

On 30/07/2019 14:12, Marco Felsch wrote:
> Hi Charles,
> 
> sorry for jumping in..
> 
> On 19-07-30 13:27, Charles Keepax wrote:
>> On Tue, Jul 30, 2019 at 01:09:35PM +0100, Thomas Preston wrote:
>>> Signed-off-by: Thomas Preston <thomas.preston@...ethink.co.uk>
>>> Cc: Patrick Glaser <pglaser@...la.com>
>>> Cc: Rob Duncan <rduncan@...la.com>
>>> Cc: Nate Case <ncase@...la.com>
>>> ---
>>>  .../devicetree/bindings/sound/tda7802.txt     | 26 +++++++++++++++++++
>>>  1 file changed, 26 insertions(+)
>>>  create mode 100644 Documentation/devicetree/bindings/sound/tda7802.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/sound/tda7802.txt b/Documentation/devicetree/bindings/sound/tda7802.txt
>>> new file mode 100644
>>> index 000000000000..f80aaf4f1ba0
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/sound/tda7802.txt
>>> @@ -0,0 +1,26 @@
>>> +ST TDA7802 audio processor
>>> +
>>> +This device supports I2C only.
>>> +
>>> +Required properties:
>>> +
>>> +- compatible : "st,tda7802"
>>> +- reg : the I2C address of the device
>>> +- enable-supply : a regulator spec for the PLLen pin
> 
> Shouldn't that be a pin called 'pllen-gpios'? IMHO I would not use a
> regulator for that.
> 
> Regards,
>   Marco
> 

Hi Marco,
We have multiple amplifiers hooked up in a chain, and all the PLLens
are connected to one GPIO. So we need to use a regulator so that
i2c-TDA7802:00 doesn't turn off the PLLen which i2c-TDA7802:01 still
requires.

This is why we use a regulator. Is there GPIO support for this?

Thanks,
Thomas