Re: [PATCH V2 1/1] USB: serial: f81232: fix incomplete serial port generation

[Peter Hong]

Hi,

Johan Hovold 於 2025/12/1 下午 09:38 寫道:
> On Fri, Nov 28, 2025 at 04:52:44PM +0800, Ji-Ze Hong (Peter Hong) wrote:
> > The Fintek F81532A/534A/535/536 family relies on the
> > F81534A_CTRL_CMD_ENABLE_PORT (116h) register during initialization to
> > both determine serial port status and control port creation. If the
> > driver experiences fast load/unload cycles, the device state may becomes
> > unstable, resulting in the incomplete generation of serial ports.
> >
> > Performing a dummy read operation on the register prior to the initial
> > write command resolves the issue. This clears the device's stale internal
> > state. Subsequent write operations will correctly generate all serial
> > ports.
> >
> > Tested on: HygonDM1SLT(Hygon C86 3250 8-core Processor)
> >
> > Signed-off-by: Ji-Ze Hong (Peter Hong) <peter_hong@xxxxxxxxxxxxx>
> > ---
> > Changelog:
> > v2:
> > 	1. remove loop in accessor function.
> Thanks for verifying.
>
> Did you try removing the retry loop also in the set_register() helper?
> Perhaps that's no longer needed after the dummy read.

I will try removing the retry loop in set_register() helper.
If that worked, could I use the same patch file or series of patches?

Thanks,


--

*洪繼澤 **Peter Hong*

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