Re: [PATCH v2 1/2] i2c: ocores: increase poll timeout to total transfer timeout

[Wolfram Sang <wsa+renesas@sang-engineering.com>]

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Hi Matthias,

> This code does not have interrupts disabled, we could not fall back from
> read_poll_timeout_atomic() to read_poll_timeout() otherwise.

Yes, that's what I thought as well.

> that a sleeping wait would make it more likely for a switch to a different task
> to happen after every byte, negatively impacting I2C performance; this is not
> something I have verified however.

Quite some prominent controller drivers use readX_poll_timeout(), so it
really seems there is no huge penalty in practice. Especially not with
cores so fast these days that tasks can be served even in 100us.

> It is spinning for 1ms because that's what the old code did (which only spun
> without fallback to sleeping).

I understand. Yet, I think the spinning is legacy behaviour and I would
prefer plain readX_poll_timeout(). Unless there is something I
overlooked. Makes the code simpler and easier to maintain.

Thanks and happy hacking,

   Wolfram


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