Re: [RFC PATCH v3.1 00/27] Add support UHS-II for GL9755

Adrian Hunter
2020-11-26T08:19:28Z

On 25/11/20 9:41 am, AKASHI Takahiro wrote:
> Gentle ping;
>
> On Fri, Nov 06, 2020 at 11:26:59AM +0900, AKASHI Takahiro wrote:
>> This is an interim snapshot of our next version, v4, for enabling
>> UHS-II on MMC/SD.
>>
>> It is focused on 'sdhci' side to address Adrian's comments regarding
>> "modularising" sdhci-uhs2.c.
>> The whole aim of this version is to get early feedback from Adrian (and
>> others) on this issue. Without any consensus about the code structure,
>
> Any comments so far?
>

Overall, I like this approach of separating UHS2 from legacy sdhci as much
as possible. The only major change, is to drop support for legacy quirks
and features that you do not need. The reason for that, is that there may
be few drivers that end up with UHS-II support (opting instead for SD
Express), so there is no point going to a lot of trouble to support things
that never get used.

From what I have seen that looks like it includes:
- any quirks
- SDHCI LED support
- external DMA support
In this regard, the important thing is to have a comment somewhere that
lists what is not supported.

I have only looked at SDHCI patches so far, and only up to about patch 20,
but maybe that gives you enough to go on for a while.