Re: [PATCH v4 2/3] dt-bindings: power: supply: qcom_bms: Add bindings

[Craig Tatlor]

On Fri, Apr 13, 2018 at 11:35:27AM -0500, Rob Herring wrote:
> On Sat, Apr 07, 2018 at 06:57:45PM +0100, Craig Tatlor wrote:
> > Add bindings for the Qualcomm Battery Monitoring system.
> > 
> > Signed-off-by: Craig Tatlor <ctatlor97@xxxxxxxxx>
> > ---
> >  .../bindings/power/supply/qcom_bms.txt        | 93 +++++++++++++++++++
> >  1 file changed, 93 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/power/supply/qcom_bms.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/power/supply/qcom_bms.txt b/Documentation/devicetree/bindings/power/supply/qcom_bms.txt
> > new file mode 100644
> > index 000000000000..6296399edc09
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/power/supply/qcom_bms.txt
> > @@ -0,0 +1,93 @@
> > +Qualcomm Battery Measurement System
> > +
> > +The Qualcomm Battery Measurement System is found inside of Qualcomm PM8941
> 
> Is it Monitoring or Measurment?
> 
> > +PMICs. It provides OCV and coulomb counter registers that allow the kernel
> > +to infer a capacity level.
> 
> s/kernel/OS/
> 
> OCV?
> 
> > +
> > +Required properties:
> > +- compatible:               Should contain "qcom,pm8941-bms".
> > +- reg:                      Specifies the SPMI address and length of the
> > +			    controller's registers.
> > +- interrupts:               OCV threshold interrupt.
> > +- io-channels:              Should contain IIO channel specifier for the
> > +			    ADC channel that reports battery temperature.
> > +- io-channel-names:         Should contain "temp".
> > +- qcom,fcc-temp-legend:     An array containing the temperature, in degC,
> > +			    for each column of the FCC lookup table.
> 
> What's FCC?
> 
> > +- qcom,fcc-lut:             An array of FCC values in mah, one entry for each
> > +			    temperature defined in in qcom,fcc-temp-legend.
> > +- qcom,ocv-temp-legend:     An array containing the temperature, in degC,
> > +			    for each column of the OCV lookup table.
> > +- qcom,ocv-capacity-legend: An array containing the capacity for each
> > +			    row of the OCV lookup table.
> > +- qcom,ocv-lut:             An array of OCV values in mV, one entry for each
> > +			    capacity defined in qcom,ocv-capacity-legend.
> 
> Need to specify the sizes of these if not 32-bit.
> 
> All these seem to have units, so add unit suffixes as defined in 
> property-units.txt.
Should i change code to use microamphours & microvolts or add a new
suffix?
> 
> > +
> > +Example:
> > +
> > +		pm8941_vadc: vadc@3100 {
> 
> adc@...
> 
> > +			compatible = "qcom,spmi-vadc";
> > +			reg = <0x3100>;
> > +			interrupts = <0x0 0x31 0x0 IRQ_TYPE_EDGE_RISING>;
> > +			#address-cells = <1>;
> > +			#size-cells = <0>;
> > +			#io-channel-cells = <1>;
> > +
> > +			bat_temp {
> > +				reg = <VADC_LR_MUX1_BAT_THERM>;
> > +			};
> > +		};
> > +
> > +		bms@4000 {
> > +			compatible = "qcom,pm8941-bms";
> > +			reg = <0x4000>;
> > +			interrupts = <0x0 0x40 0x4 IRQ_TYPE_EDGE_RISING>;
> > +			interrupt-names = "ocv_thr";
> > +
> > +			io-channels = <&pm8941_vadc VADC_LR_MUX1_BAT_THERM>;
> > +			io-channel-names = "temp";
> > +
> > +			qcom,fcc-temp-legend = /bits/ 8 <(-10) 0 25 50 65>;
> > +			qcom,fcc-lut = /bits/ 16 <6010 6070 6680 6780 6670>;
> > +
> > +			qcom,ocv-capacity-legend = /bits/ 8 <100 95 90 85
> > +							     80 75 70 65
> > +							     60 55 50 45
> > +							     40 35 30 25
> > +							     20 15 10 9
> > +							     8 7 6 5 4
> > +							     3 2 1 0>;
> > +
> > +			qcom,ocv-temp-legend = /bits/ 8 <(-10) 0 25 50 65>;
> > +			qcom,ocv-lut = /bits/ 16 <4288 4288 4306 4315 4315
> > +						  4261 4241 4259 4266 4246
> > +						  4201 4181 4201 4207 4187
> > +						  4153 4133 4150 4155 4135
> > +						  4105 4085 4100 4104 4084
> > +						  4058 4038 4052 4058 4038
> > +						  4012 3992 4004 4014 3994
> > +						  3970 3950 3959 3971 3951
> > +						  3931 3911 3915 3927 3907
> > +						  3899 3879 3880 3884 3864
> > +						  3873 3853 3851 3853 3833
> > +						  3848 3828 3827 3829 3809
> > +						  3829 3809 3808 3809 3789
> > +						  3815 3795 3791 3791 3771
> > +						  3801 3781 3775 3772 3752
> > +						  3785 3765 3751 3746 3726
> > +						  3767 3747 3727 3719 3699
> > +						  3750 3730 3702 3692 3672
> > +						  3728 3708 3680 3672 3652
> > +						  3720 3700 3676 3665 3645
> > +						  3712 3692 3670 3660 3645
> > +						  3695 3675 3658 3648 3633
> > +						  3662 3647 3629 3620 3610
> > +						  3620 3605 3589 3580 3570
> > +						  3562 3552 3538 3529 3519
> > +						  3490 3480 3474 3470 3465
> > +						  3403 3398 3388 3380 3375
> > +						  3320 3300 3255 3221 3206
> > +						  3000 3000 3000 3000 3000>;
> > +		};
> > +	};
> > +};
> > -- 
> > 2.17.0
> >