xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/power/supply/ltc2941.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyunbinding for LTC2941, LTC2942, LTC2943 and LTC2944 battery gauges
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunAll chips measure battery capacity.
4*4882a593SmuzhiyunThe LTC2942 is pin compatible with the LTC2941, it adds voltage and
5*4882a593Smuzhiyuntemperature monitoring, and is runtime detected. LTC2943 and LTC2944
6*4882a593Smuzhiyunis software compatible, uses a slightly different conversion formula
7*4882a593Smuzhiyunfor the charge counter and adds voltage, current and temperature monitoring.
8*4882a593Smuzhiyun
9*4882a593SmuzhiyunRequired properties:
10*4882a593Smuzhiyun- compatible: Should contain "lltc,ltc2941", "lltc,ltc2942", "lltc,ltc2943"
11*4882a593Smuzhiyun    or "lltc,ltc2944" which also indicates the type of I2C chip attached.
12*4882a593Smuzhiyun- reg: The 7-bit I2C address.
13*4882a593Smuzhiyun- lltc,resistor-sense: The sense resistor value in milli-ohms. Can be a 32-bit
14*4882a593Smuzhiyun    negative value when the battery has been connected to the wrong end of the
15*4882a593Smuzhiyun    resistor.
16*4882a593Smuzhiyun- lltc,prescaler-exponent: The prescaler exponent as explained in the datasheet.
17*4882a593Smuzhiyun    This determines the range and accuracy of the gauge. The value is programmed
18*4882a593Smuzhiyun    into the chip only if it differs from the current setting. The setting is
19*4882a593Smuzhiyun    lost when the battery is disconnected.
20*4882a593Smuzhiyun
21*4882a593SmuzhiyunExample from the Topic Miami Florida board:
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun	fuelgauge: ltc2943@64 {
24*4882a593Smuzhiyun		compatible = "lltc,ltc2943";
25*4882a593Smuzhiyun		reg = <0x64>;
26*4882a593Smuzhiyun		lltc,resistor-sense = <15>;
27*4882a593Smuzhiyun		lltc,prescaler-exponent = <5>; /* 2^(2*5) = 1024 */
28*4882a593Smuzhiyun	};
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