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From 585ea300fa44cdf3c3259af68c49518bb85e4af2 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Tue, 1 May 2018 09:35:56 +0100
Subject: [PATCH 289/454] overlays: Add ltc294x (battery gauge)
Support the LTC294x range of I2C-connected battery monitors.
See: https://github.com/raspberrypi/linux/issues/2537
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
arch/arm/boot/dts/overlays/Makefile | 1 +
arch/arm/boot/dts/overlays/README | 25 ++++++
.../arm/boot/dts/overlays/ltc294x-overlay.dts | 86 +++++++++++++++++++
3 files changed, 112 insertions(+)
create mode 100644 arch/arm/boot/dts/overlays/ltc294x-overlay.dts
--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -60,6 +60,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
justboom-dac.dtbo \
justboom-digi.dtbo \
lirc-rpi.dtbo \
+ ltc294x.dtbo \
mbed-dac.dtbo \
mcp23017.dtbo \
mcp23s17.dtbo \
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -1020,6 +1020,31 @@ Params: gpio_out_pin GPIO for
(default "off")
+Name: ltc294x
+Info: Adds support for the ltc294x family of battery gauges
+Load: dtoverlay=ltc294x,<param>=<val>
+Params: ltc2941 Select the ltc2941 device
+
+ ltc2942 Select the ltc2942 device
+
+ ltc2943 Select the ltc2943 device
+
+ ltc2944 Select the ltc2944 device
+
+ resistor-sense The sense resistor value in milli-ohms.
+ Can be a 32-bit negative value when the battery
+ has been connected to the wrong end of the
+ resistor.
+
+ prescaler-exponent Range and accuracy of the gauge. The value is
+ programmed into the chip only if it differs
+ from the current setting.
+ For LTC2941 only:
+ - Default value is 128
+ - the exponent is in the range 0-7 (default 7)
+ See the datasheet for more information.
+
+
Name: mbed-dac
Info: Configures the mbed AudioCODEC (TLV320AIC23B)
Load: dtoverlay=mbed-dac
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/ltc294x-overlay.dts
@@ -0,0 +1,86 @@
+/dts-v1/;
+/plugin/;
+
+
+/ {
+ compatible = "brcm,bcm2835";
+
+ fragment@0 {
+ target = <&i2c_arm>;
+ __dormant__ {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ ltc2941: ltc2941@64 {
+ compatible = "lltc,ltc2941";
+ reg = <0x64>;
+ lltc,resistor-sense = <50>;
+ lltc,prescaler-exponent = <7>;
+ };
+ };
+ };
+
+ fragment@1 {
+ target = <&i2c_arm>;
+ __dormant__ {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ ltc2942: ltc2942@64 {
+ compatible = "lltc,ltc2942";
+ reg = <0x64>;
+ lltc,resistor-sense = <50>;
+ lltc,prescaler-exponent = <7>;
+ };
+ };
+ };
+
+ fragment@2 {
+ target = <&i2c_arm>;
+ __dormant__ {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ ltc2943: ltc2943@64 {
+ compatible = "lltc,ltc2943";
+ reg = <0x64>;
+ lltc,resistor-sense = <50>;
+ lltc,prescaler-exponent = <7>;
+ };
+ };
+ };
+
+ fragment@3 {
+ target = <&i2c_arm>;
+ __dormant__ {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ ltc2944: ltc2944@64 {
+ compatible = "lltc,ltc2944";
+ reg = <0x64>;
+ lltc,resistor-sense = <50>;
+ lltc,prescaler-exponent = <7>;
+ };
+ };
+ };
+
+ __overrides__ {
+ ltc2941 = <0>,"+0";
+ ltc2942 = <0>,"+1";
+ ltc2943 = <0>,"+2";
+ ltc2944 = <0>,"+3";
+ resistor-sense = <<c2941>, "lltc,resistor-sense:0",
+ <<c2942>, "lltc,resistor-sense:0",
+ <<c2943>, "lltc,resistor-sense:0",
+ <<c2944>, "lltc,resistor-sense:0";
+ prescaler-exponent = <<c2941>, "lltc,prescaler-exponent:0",
+ <<c2942>, "lltc,prescaler-exponent:0",
+ <<c2943>, "lltc,prescaler-exponent:0",
+ <<c2944>, "lltc,prescaler-exponent:0";
+ };
+};
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