Messages in this thread | | | Date | Tue, 27 Jan 2015 23:34:55 +0100 | From | Jean Delvare <> | Subject | Re: [lm-sensors] [PATCH] hwmon: (ads7828) Make sample interval configurable |
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On Tue, 27 Jan 2015 12:05:53 -0800, Guenter Roeck wrote: > On Tue, Jan 27, 2015 at 08:54:34PM +0100, Robert Rosengren wrote: > > Guenter and Jean, > > > > To sum up, my problems was related my kernel and hardware configuration, and it now works. Many thanks for your input! > > > > However, the values retrieved from hwmon sysfs is not the same as before the regmap patch. Guenter, the byte swap for the regval retrieved by regmap_read. In what order is the bits returned from that function, because it seems as if I disabled that code I get values as I expect (i.e. before the regmap patch). > > > Trying to understand. Are you saying everything works as expected > if you keep byte_swap set to false ? > > That might well be, though it might mean that regmap has a bug > in how it treats i2c word read operations. I'll have to look into it > some more.
Remember that SMBus specifies that the LSB comes first (and i2c-core implement things that way) while real I2C devices typically send the MSB first. This has always caused confusion. This is why a lot of drivers need byte-swapping.
-- Jean Delvare SUSE L3 Support
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