Messages in this thread | | | Date | Fri, 27 Sep 2013 20:22:33 +0100 | From | Mark Brown <> | Subject | Re: [PATCH 1/3] spi: Add a spi_w8r16be() helper |
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On Fri, Sep 27, 2013 at 08:46:56PM +0200, Lars-Peter Clausen wrote:
> According to the documentation of spi_w8r16() it is a feature.
> * The number is returned in wire-order, which is at least sometimes > * big-endian.
Indeed. I don't think that's terribly well thought through though, especially not now we have annotations for endianness (as you noticed!).
> There seem to be at least two users though which assume that the result is > in native endianness drivers/hwmon/ads7871.c and drivers/mfd/stmpe-spi.c
Yeah, I saw. The ads7871 is just going to break when run on the opposite endianness to the one it was (hopefully) tested on since it doesn't make any effort I saw to cope with endianness. Looking at the history it's not terribly obvious which that was but it'd be surprising to see a little endian register...
STMPE is doing a byte swap so it's another user for your function - it's for ARM systems so it'll be assuming that little endian is the native format. [unhandled content-type:application/pgp-signature] | |