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

From: Kumar Gala
Date: Fri Mar 31 2006 - 18:55:44 EST



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
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