Re: [PATCH v2 2/4] serial: 8250_dw: Only accept a contiguous DLF readback

[Vinicius Pedrosa]

Hi Ilpo,

On Tue, 20 Oct 2026, Ilpo Järvinen wrote:

> For is_power_of_2(), 0 is not a power of two. And it also wouldn't make
> sense to have zero bits in the bit field as it's same as no bit field so
> using just is_power_of_2() should be enough.

I think the reg != 0 check still needs to stay here, since the test is
is_power_of_2(reg + 1), rather than is_power_of_2(reg).

For reg == 0, reg + 1 is 1, and is_power_of_2(1) is true. So without
the explicit reg check, a zero readback, meaning no DLF, would be
accepted as a valid DLF.

I'll keep it as:

    reg && is_power_of_2(reg + 1)

in v3.

Thanks,
Vinicius