On Wed, Mar 19, 2014 at 11:43:55PM +0800, Axel Lin wrote: > 2014-03-19 16:06 GMT+08:00 Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>: > > Just wondering: are there any SPI slave drivers that implement dummy cycles > > this way? > I think I found one such case: > drivers/net/wireless/libertas/if_spi.c > the dummy_trans has non-zero length, and both tx_buf and rx_buf are NULL. > But that means it doesn't work with master drivers with this checking, e.g. > all drivers using bitbang library has this checking. I have to say that this seems rather abusive on the part of the driver, it's going to cause implementation issues in the masters - I expect more than just those that check aren't doing to do the right thing.
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