Re: [PATCH 2/2] Documentation: cs35l41: Shared boost properties

From: lucas . tanure
Date: Tue Feb 07 2023 - 12:03:39 EST


On 2/7/23 4:48 PM, Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> wrote:
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


The value does exist in the code, but no device should have that in ACPI/DTB, so yes the value doesn't exist for ACPI/DTB purposes.
I can change CS35L41_EXT_BOOST_NO_VSPK_SWITCH to another value, like 99, and use 2 and 3 for shared boost.
I will re-submit that with v3.
Is that ok with you?

Thanks
Lucas