0001 Kernel drivers ltc2947-i2c and ltc2947-spi
0002 ==========================================
0003
0004 Supported chips:
0005
0006 * Analog Devices LTC2947
0007
0008 Prefix: 'ltc2947'
0009
0010 Addresses scanned: -
0011
0012 Datasheet:
0013
0014 https://www.analog.com/media/en/technical-documentation/data-sheets/LTC2947.pdf
0015
0016 Author: Nuno Sá <nuno.sa@analog.com>
0017
0018 Description
0019 ___________
0020
0021 The LTC2947 is a high precision power and energy monitor that measures current,
0022 voltage, power, temperature, charge and energy. The device supports both SPI
0023 and I2C depending on the chip configuration.
0024 The device also measures accumulated quantities as energy. It has two banks of
0025 register's to read/set energy related values. These banks can be configured
0026 independently to have setups like: energy1 accumulates always and enrgy2 only
0027 accumulates if current is positive (to check battery charging efficiency for
0028 example). The device also supports a GPIO pin that can be configured as output
0029 to control a fan as a function of measured temperature. Then, the GPIO becomes
0030 active as soon as a temperature reading is higher than a defined threshold. The
0031 temp2 channel is used to control this thresholds and to read the respective
0032 alarms.
0033
0034 Sysfs entries
0035 _____________
0036
0037 The following attributes are supported. Limits are read-write, reset_history
0038 is write-only and all the other attributes are read-only.
0039
0040 ======================= ==========================================
0041 in0_input VP-VM voltage (mV).
0042 in0_min Undervoltage threshold
0043 in0_max Overvoltage threshold
0044 in0_lowest Lowest measured voltage
0045 in0_highest Highest measured voltage
0046 in0_reset_history Write 1 to reset in1 history
0047 in0_min_alarm Undervoltage alarm
0048 in0_max_alarm Overvoltage alarm
0049 in0_label Channel label (VP-VM)
0050
0051 in1_input DVCC voltage (mV)
0052 in1_min Undervoltage threshold
0053 in1_max Overvoltage threshold
0054 in1_lowest Lowest measured voltage
0055 in1_highest Highest measured voltage
0056 in1_reset_history Write 1 to reset in2 history
0057 in1_min_alarm Undervoltage alarm
0058 in1_max_alarm Overvoltage alarm
0059 in1_label Channel label (DVCC)
0060
0061 curr1_input IP-IM Sense current (mA)
0062 curr1_min Undercurrent threshold
0063 curr1_max Overcurrent threshold
0064 curr1_lowest Lowest measured current
0065 curr1_highest Highest measured current
0066 curr1_reset_history Write 1 to reset curr1 history
0067 curr1_min_alarm Undercurrent alarm
0068 curr1_max_alarm Overcurrent alarm
0069 curr1_label Channel label (IP-IM)
0070
0071 power1_input Power (in uW)
0072 power1_min Low power threshold
0073 power1_max High power threshold
0074 power1_input_lowest Historical minimum power use
0075 power1_input_highest Historical maximum power use
0076 power1_reset_history Write 1 to reset power1 history
0077 power1_min_alarm Low power alarm
0078 power1_max_alarm High power alarm
0079 power1_label Channel label (Power)
0080
0081 temp1_input Chip Temperature (in milliC)
0082 temp1_min Low temperature threshold
0083 temp1_max High temperature threshold
0084 temp1_input_lowest Historical minimum temperature use
0085 temp1_input_highest Historical maximum temperature use
0086 temp1_reset_history Write 1 to reset temp1 history
0087 temp1_min_alarm Low temperature alarm
0088 temp1_max_alarm High temperature alarm
0089 temp1_label Channel label (Ambient)
0090
0091 temp2_min Low temperature threshold for fan control
0092 temp2_max High temperature threshold for fan control
0093 temp2_min_alarm Low temperature fan control alarm
0094 temp2_max_alarm High temperature fan control alarm
0095 temp2_label Channel label (TEMPFAN)
0096
0097 energy1_input Measured energy over time (in microJoule)
0098
0099 energy2_input Measured energy over time (in microJoule)
0100 ======================= ==========================================
