Re: [spi-devel-general] Re: question on spi_bitbang

[Kumar Gala <galak@kernel.crashing.org>]

On Mar 31, 2006, at 4:20 PM, David Brownell wrote:

> On Friday 31 March 2006 2:11 pm, Kumar Gala wrote:
>
>> So I give a new question.  Any issue with adding a rx & tx completion
>> to spi_bitbang?
>
> What do you mean?
>
>> In my HW I get an interrupt when the transmitter is
>> done transmitting and one when the receiver is done receiving.  I
>> need some way to synchronize and wait for both events to occur before
>> continuing on in txrx_word().
>
> You can't return from txrx_word() before the RX event, since the
> return value is the word that was shifted in.  So if you use IRQs
> to synchronize there (rather than polling a status register), all
> that would be internal to your code.

Your right, I just put this in my struct that wraps spi_bitbang.

It's too bad we dont have a better solution for spi_bitbang having to  
be first.

I've got a working driver w/o using the setup_transfer() mods, I'll  
look at fixing that up next.

- kumar