Kmod driver at iicbus. attach() and config_intrhook(9)

Alexander Mishin mishin at mh.net.ru
Thu Sep 3 11:02:38 UTC 2020


Andriy Gapon писал 2020-09-03 11:29:
> On 02/09/2020 01:18, John-Mark Gurney wrote:
>> So my reading of the twsi driver is that it handles things correctly
>> allowing devices pre-interrupts to attach, and using interrupts for
>> transfers post-cold.
> 
> I just want to note that twsi uses _completely_ different code for 
> polled and
> interrupt modes.  So, while either mode should be active at correct 
> times, I
> cannot certify that the polled mode works correctly for all transfer 
> types.
> I haven't reviewed the polled mode code.

This adds some more light on my question.

As a result:
For twsi I use iicbb_transfer() (as Emmanuel Vadot recommended to 
someone on the mailing list).
It is definitely not works for my driver, until interrupts went enabled. 
But it works perfectly well with the config_intrhook().

I have never tried iicbus_write() at boot time yet, but I think I'll 
try, just to know for the future.

Thanks


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