Qualcomm's QPNP PMIC thermal monitor ADC driver (VADC_TM) QPNP PMIC thermal monitoring (TM) provides interface to thermal clients to set temperature thresholds and receive notification when the thresholds are crossed. A 15 bit ADC is used for measurements. The driver is part of the sysfs thermal framework that provides support to read the trip points, set threshold for the trip points and enable the trip points. Seperate kernel api's are provided to usb_id and batt_therm to set thresholds and receive threshold notifications. VADC_TM node Required properties: - compatible : should be "qcom,qpnp-adc-tm" for thermal ADC driver. - reg : offset and length of the PMIC Aribter register map. - address-cells : Must be one. - size-cells : Must be zero. - interrupts : The thermal ADC bank peripheral interrupts for eoc, high and low interrupts. - interrupt-names : Should be "eoc-int-en-set", "high-thr-en-set" and "low-thr-en-set". - qcom,adc-bit-resolution : Bit resolution of the ADC. - qcom,adc-vdd-reference : Voltage reference used by the ADC. Optional properties: - qcom,thermal-node : If present a thermal node is created and the channel is registered as part of the thermal sysfs which allows clients to use the thermal framework to set temperature thresholds and receive notification when the temperature crosses a set threshold, read temperature and enable/set trip types supported by the thermal framework. - qcom,meas-interval-timer-idx: If present select from the following timer index to choose a preset configurable measurement interval timer value. The driver defaults to timer 2 with a measurement interval of 1 second if the property is not present. 0 : Select Timer 1 for a measurement polling interval of 3.9 milliseconds. 1 : Select Timer 2 for a measurement polling interval of 1 second. 2 : Select Timer 3 for a measurement polling interval of 4 seconds. - qcom,adc-tm-recalib-check: Add this property to check if recalibration required due to inaccuracy. - hkadc_ldo-supply : Add this property if VADC needs to perform a Software Vote for the HKADC. - hkadc_ok-supply : Add this property if the VADC needs to perform a Software vote for the HKADC VREG_OK. Client required property: - qcom,-adc_tm : The phandle to the corresponding adc_tm device. The consumer name passed to the driver when calling qpnp_get_adc_tm() is used to associate the client with the corresponding device. Channel nodes NOTE: Atleast one Channel node is required. Required properties: - label : Channel name used for sysfs entry. - reg : AMUX channel number. - qcom,decimation : Sampling rate to use for the individual channel measurement. Select from the following unsigned int. 0 : 512 1 : 1K 2 : 2K 3 : 4K - qcom,pre-div-channel-scaling : Pre-div used for the channel before the signal is being measured. Select from the following unsigned int for the corresponding numerator/denominator pre-div ratio. 0 : pre-div ratio of {1, 1} 1 : pre-div ratio of {1, 3} 2 : pre-div ratio of {1, 4} 3 : pre-div ratio of {1, 6} 4 : pre-div ratio of {1, 20} 5 : pre-div ratio of {1, 8} 6 : pre-div ratio of {10, 81} 7 : pre-div ratio of {1, 10} - qcom,calibration-type : Reference voltage to use for channel calibration. Channel calibration is dependendent on the channel. Certain channels like XO_THERM, BATT_THERM use ratiometric calibration. Most other channels fall under absolute calibration. Select from the following strings. "absolute" : Uses the 625mv and 1.25V reference channels. "ratiometric" : Uses the reference Voltage/GND for calibration. - qcom,scale-function : Reverse scaling fuction used to convert raw ADC code to units specific to a given channel. Select from the following unsigned int. 0 : Scaling to convert voltage in uV to raw adc code. 1 : Scaling to convert decidegC to raw adc code. 2 : Scaling for converting USB_ID reverse scaling. 3 : Scaling to convert milldegC to raw ADC code. 4 : Scaling to convert smb_batt_therm values to raw ADC code. 5 : Scaling to perform reverse calibration for absolute voltage from uV to raw ADC code. 6 : Scaling to convert qrd skuh battery decidegC to raw ADC code. - qcom,hw-settle-time : Settling period for the channel before ADC read. Select from the following unsigned int. 0 : 0us 1 : 100us 2 : 200us 3 : 300us 4 : 400us 5 : 500us 6 : 600us 7 : 700us 8 : 800us 9 : 900us 0xa : 1ms 0xb : 2ms 0xc : 4ms 0xd : 6ms 0xe : 8ms 0xf : 10ms - qcom,fast-avg-setup : Average number of samples to be used for measurement. Fast averaging provides the option to obtain a single measurement from the ADC that is an average of multiple samples. The value selected is 2^(value) Select from 0 : 1 1 : 2 2 : 4 3 : 8 4 : 16 5 : 32 6 : 64 7 : 128 8 : 256 - qcom,btm-channel-number : Depending on the PMIC version, a max of upto 8 BTM channels. The BTM channel numbers are statically allocated to the corresponding channel node. - qcom,adc_tm-vadc : phandle to the corresponding VADC device to read the ADC channels. Client device example: /* Add to the clients node that needs the ADC_TM channel A/D */ client_node { qcom,client-adc_tm = <&pm8941_adc_tm>; }; Example: /* Main Node */ qcom,vadc@3400 { compatible = "qcom,qpnp-adc-tm"; reg = <0x3400 0x100>; #address-cells = <1>; #size-cells = <0>; interrupts = <0x0 0x34 0x0>, <0x0 0x34 0x3>, <0x0 0x34 0x4>; interrupt-names = "eoc-int-en-set", "high-thr-en-set", "low-thr-en-set"; qcom,adc-bit-resolution = <15>; qcom,adc-vdd-reference = <1800>; qcom,adc_tm-vadc = <&pm8941_vadc>; /* Channel Node to be registered as part of thermal sysfs */ chan@b5 { label = "pa_therm1"; reg = <0xb5>; qcom,decimation = <0>; qcom,pre-div-channel-scaling = <0>; qcom,calibration-type = "absolute"; qcom,scale-function = <2>; qcom,hw-settle-time = <0>; qcom,fast-avg-setup = <0>; qcom,btm-channel-number = <0x70>; qcom,thermal-node; }; /* Channel Node */ chan@6 { label = "vbat_sns"; reg = <6>; qcom,decimation = <0>; qcom,pre-div-channel-scaling = <1>; qcom,calibration-type = "absolute"; qcom,scale-function = <3>; qcom,hw-settle-time = <0>; qcom,fast-avg-setup = <0>; qcom,btm-channel-number = <0x78>; }; };