Fix fan speed regression for some xiaomi fans

[peteh]

Proposed change

In my original PR (#77626) I assumed all miot based fans would have the problem that the speed level is 3-4 values only instead of percentage. However, this holds only true for the 1c fan. So my previous PR fixed the 1c fan but broke the others.

This PR only handles the 1c fan as an exception and reverts to the previous behavior for the other fans.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Smartmi Standing Fan 3 (zhimi.fan.za5) wrong intensity. #78148
• This PR is related to issue: Speed does not work for dmaker.fan.1c #75811
• Link to documentation pull request:

Checklist

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[probot-home-assistant]

Hey there @rytilahti, @syssi, @starkillerOG, @bieniu, mind taking a look at this pull request as it has been labeled with an integration (xiaomi_miio) you are listed as a code owner for? Thanks!
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[rytilahti]

LGTM, nice cleanup, too! 👍 Let's wait for someone with a test device to verify that it's working, but I'm marking this already for the next patch release.

[MartinHjelmare]

Thanks!

[peteh]

Quick question, how do we make sure that somebody tests it? I only have the 1c fan and already verified the behavior but cannot test for other fan types. Technically the code is reverted for the other fans to the known-to-be-working state, but I cannot verify this.

[rytilahti]

Alas, there is no easy way for that, besides having enough unit tests. In this case, considering the current level of code coverage, I'd argue against adding more tests if only done for a single device. I'm slowly trying to move all relevant information to python-miio, which will make it the only ground truth for device specifics, but it's a slow process as I don't have test devices either.

@peteh considering you know how to do development work, could you please consider checking out rytilahti/python-miio#1495 and adding the necessary metadata decorators to python-miio to help remove hardcoding? There is a link to my homeassistant fork that makes use of the library-provided information to make testing a breeze :-)