Re: [PATCH] Add Dallas DS1390 RTC chip

From: Mark Jackson
Date: Fri Oct 17 2008 - 15:28:02 EST

David Brownell wrote:
On Friday 17 October 2008, Mark Jackson wrote:
+ /* Can tx_buf and rx_buf be equal? The doc in spi.h is not sure... */
+ xfer.tx_buf = chip->tx_buf;
+ xfer.rx_buf = chip->rx_buf;
you use the same buffer a few functions below. either
one way or the other. please investigate with the spi subsystem maintainer.

Just to double check (as per Alessandro's suggestion), is this okay use of the spi buffers ?

Yes. That comment deserves to be updated.

SPI does bi-directional I/O, and the underlying controller
should be able to just replace the contents of a buffer
with a spi_transfer that uses the same rx and tx buffers.

Excellent. Thanks for the confirmation.

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