Message-ID: <56ce2617-4fd1-d597-a4dc-918654cdd3f6@linaro.org>
Date:   Tue, 7 Feb 2023 17:48:59 +0100
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Subject: Re: [PATCH 2/2] Documentation: cs35l41: Shared boost properties
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To:     Lucas Tanure <lucas.tanure@collabora.com>,
        David Rhodes <david.rhodes@cirrus.com>,
        Charles Keepax <ckeepax@opensource.cirrus.com>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Mark Brown <broonie@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>
Cc:     alsa-devel@alsa-project.org, devicetree@vger.kernel.org,
        patches@opensource.cirrus.com, linux-kernel@vger.kernel.org,
        kernel@collabora.com
References: <20230207104021.2842-1-lucas.tanure@collabora.com>
 <20230207104021.2842-3-lucas.tanure@collabora.com>
 <44faeca1-94c9-4423-d87a-03d80e286812@linaro.org>
 <e7257f9a-86c5-74e8-c538-6f6d2ba13274@collabora.com>
 <44c7274f-8a5e-0235-413a-6c3260018601@linaro.org>
 <4efe9796-6d3e-09d1-d5f7-cfb25a439061@collabora.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <4efe9796-6d3e-09d1-d5f7-cfb25a439061@collabora.com>
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Precedence: bulk

On 07/02/2023 17:34, Lucas Tanure wrote:
> On 07-02-2023 16:13, Krzysztof Kozlowski wrote:
>> On 07/02/2023 16:46, Lucas Tanure wrote:
>>>>> +      Shared boost allows two amplifiers to share a single boost circuit by
>>>>> +      communicating on the MDSYNC bus. The passive amplifier does not control
>>>>> +      the boost and receives data from the active amplifier. GPIO1 should be
>>>>> +      configured for Sync when shared boost is used. Shared boost is not
>>>>> +      compatible with External boost. Active amplifier requires
>>>>> +      boost-peak-milliamp, boost-ind-nanohenry and boost-cap-microfarad.
>>>>>          0 = Internal Boost
>>>>>          1 = External Boost
>>>>> +      2 = Reserved
>>>>
>>>> How binding can be reserved? For what and why? Drop. 2 is shared active,
>>>> 3 is shared passive.
>>> 2 Is shared boost without VSPK switch, a mode not supported for new
>>> system designs. But there is laptops using it, so we need to keep
>>> supporting in the driver.
>>
>> That's not the answer. 2 is nothing here, so it cannot be reserved.
>> Aren't you mixing now some register value with bindings?
>>
>> Best regards,
>> Krzysztof
>>
>>
> I have added a new patch with propper documentation.
> And I would like to use 3 and 4 for shared boost as 
> CS35L41_EXT_BOOST_NO_VSPK_SWITCH already exist as 2 and is used in the 
> current driver.

I don't see CS35L41_EXT_BOOST_NO_VSPK_SWITCH in the bindings.

> The laptop that uses CS35L41_EXT_BOOST_NO_VSPK_SWITCH doesn't have the 
> property "cirrus,boost-type", but to make everything consistent I would 
> prefer to use 3 and 4 for the new boost types.
> Is that ok with you?

I don't see how it is related. The value does not exist, so whether
laptop has that property or not, is not really related, right?

Best regards,
Krzysztof