Mark Rutland <mark.rutland@xxxxxxx> writes: > On Mon, Sep 14, 2015 at 03:38:36PM +0100, Punit Agrawal wrote: >> Mark Rutland <mark.rutland@xxxxxxx> writes: >> >> >> >> +Sensor bindings for the sensors based on SCPI Message Protocol >> >> >> +-------------------------------------------------------------- >> >> >> +SCPI provides an API to access the various sensors on the SoC. >> >> >> + >> >> >> +Required properties: >> >> >> +- compatible : should be "arm,scpi-sensors". >> >> >> +- #thermal-sensor-cells: should be set to 1. This property follows the >> >> >> + thermal device tree bindings[2]. >> >> > >> >> > You need to specify what the valid values for this cell are. >> >> >> >> The enumeration depends on the number of sensors exported by SCP >> >> firmware - which is platform dependent. I could add add something like >> >> if you think that is helpful - >> >> >> >> "Valid cell value is a number between 0..n-1, where n is the number >> >> of sensors exported by SCP firmware." >> > >> > Can the FW identifer space have holes? Or are they always contiguous? >> >> The way the SCP interface is defined, the sensor identifiers are >> contiguous, but not all are temperature sensors. > > Ok. So how exactly are they enumerated for this binding? The sensor enumeration for r0 (which I've verified) and r1 can be found at [0]. The valid cell values are identifiers for the temperature sensors. > >> > If this is the same as the raw FW identifer value, specify that. >> > Otherwise, you need to specify the mapping. >> >> I'll update the patch to add mappings for Juno r0 (and r1 if I can get >> my hands on one). > > If there's identical logic mapping the two, we might just be able to > describe that rather than having to add tables all the time. > After seeing the mapping already published, I am wondering if there is any value in duplicating the information. If there are no objections, I'll update this patch to add pointers instead. >> > There needs to be enough information for a dts author to figure out >> > which values to place in the DT. >> >> I understand. Except sometimes it is hard to get the firmware to commit to not >> modify the ordering - discoverability and all that. :) > > If they do that, then things are broken regardless, no? I guess that'll > be clear if/when I see how the mapping works. [0] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0922b/apas03s22.html > > Thanks, > Mark. > -- > To unsubscribe from this list: send the line "unsubscribe devicetree" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
