FSL SPI driver question

Bruce_Leonard at selinc.com Bruce_Leonard at selinc.com
Thu Jan 26 06:49:36 EST 2012

Hi Norbert,

> >
> > So the question is, how do I use spidev (or any other means) to get 
> > 8308 SPI controller to keep SPICLK active so that the output data from 
> > NvRAM gets clocked out to the 8308?
> >
> Did you see Documentation/spi/spidev_fdx.c:do_msg ?
> it perform a full-duplex (actually half-duplex) 1 byte transfer.
> In your case you need a transfer that outputs 3 bytes (read cmd + 
> and inputs 1? byte.
> If you do it this way I would expect the SPICLK to be active
> during the 2nd part of the transfer (whenever the CPU "reads" the
> data from SPI client).

Thanks for the reply.  Yes I did find spidev_fdx.c and in fact copied it 
for my tests.  I still see SPICLK active only during the time the 8308 is 
sending data (read cmd + address).  Nothing happens with the clock after 
that when the NvRAM is ready to send data.


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