Re: [PATCH v4 05/13] iio: adc: ad4134: Run shorter transfers when CRC is disabled

[Nuno Sá]

On Tue, 06 Oct 2026 15:17:19 -0300, Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx> wrote:
> When AD4134 has its SPI CRC feature enabled, one extra byte (the CRC code)
> is sent through SPI for both ends to verify the integrity of data
> transfers. Though, when CRC is not enabled, SPI transfers can be shorter.
> 
> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>

Hmm, still don't get the crc story... Are you saying crc just does not work as it
is? What's the point then :)? I think it should very much be fixed. And
It's indeed odd to compare the crc over different payloads. The normal
way is that on receive, you compute it again and compare it against what
you got from the device. Pretty sure that's what the device is doing (or
at least it should). Might be missing something but not sure why we
would need spi core changes. See this for example:

https://elixir.bootlin.com/linux/v7.2.10/source/drivers/iio/imu/adis16550.c#L193

Anyways not related to this patch so:

Reviewed-by: Nuno Sá <nuno.sa@xxxxxxxxxx>

-- 
Nuno Sá <nuno.sa@xxxxxxxxxx>