Re: [PATCH v2 1/4] serial: 8250_dw: Keep the BUSY-safe divisor hook when DLF is present

[Andy Shevchenko]

On Wed, Oct 21, 2026 at 02:04:03PM -0300, Vinicius Pedrosa wrote:
> On Wed, 21 Oct 2026, Andy Shevchenko wrote:

...

> > I dunno, I prefer just a longer solution, but I don't know how big this issue
> > is that we need to backport in that way (and not taking the whole series as a
> > fix).
> 
> On the severity: the IER restore comes from a7b9ce39fbe4. On the A733 I
> saw hardware IER left at 0 and the console stop taking TX/RX
> interrupts. I haven't tested this on hardware with a real DLF.

Yes. but is it only a single device/platform affected or a big class of the
devices? I assume only narrow part of them which unfortunately use DFL register
offset for something else in their RTL.

> Given that, how about keeping the small fix as patch 1 with the stable
> tag, and putting the refactoring after it in the same series? That would
> keep the fix independently backportable if needed, while mainline would
> still end up with the structure you proposed.

It all depends on the outcome of the above discussion. Maybe others can share
their opinions, but I lean towards a series-as-a-fix rather than a bit ugly fix
+ proper refactoring on top.

The whole approach doesn't seem to me like a pile of changes. The deduplication
patch can be deferred for later actually.

-- 
With Best Regards,
Andy Shevchenko