From 17825ff6ec6db23892e61a1496abf7d737afe9e7 Mon Sep 17 00:00:00 2001 From: Dragos Bogdan Date: Sun, 16 Jul 2017 11:35:32 +0200 Subject: [PATCH] power: supply: ltc2941-battery-gauge: Add LTC2944 support LTC2944 is compatible with LTC2943, but uses different voltage and current computing constants. Signed-off-by: Dragos Bogdan Signed-off-by: Ladislav Michl Tested-by: Dragos Bogdan Acked-by: Rob Herring Signed-off-by: Sebastian Reichel --- .../devicetree/bindings/power/supply/ltc2941.txt | 12 +++++----- drivers/power/supply/ltc2941-battery-gauge.c | 27 ++++++++++++++++++---- 2 files changed, 28 insertions(+), 11 deletions(-) diff --git a/Documentation/devicetree/bindings/power/supply/ltc2941.txt b/Documentation/devicetree/bindings/power/supply/ltc2941.txt index 8ec1036..3b9ba14 100644 --- a/Documentation/devicetree/bindings/power/supply/ltc2941.txt +++ b/Documentation/devicetree/bindings/power/supply/ltc2941.txt @@ -1,14 +1,14 @@ -binding for LTC2941, LTC2942 and LTC2943 battery gauges +binding for LTC2941, LTC2942, LTC2943 and LTC2944 battery gauges All chips measure battery capacity. The LTC2942 is pin compatible with the LTC2941, it adds voltage and -temperature monitoring, and is runtime detected. LTC2943 is software -compatible, uses a slightly different conversion formula for the -charge counter and adds voltage, current and temperature monitoring. +temperature monitoring, and is runtime detected. LTC2943 and LTC2944 +is software compatible, uses a slightly different conversion formula +for the charge counter and adds voltage, current and temperature monitoring. Required properties: -- compatible: Should contain "lltc,ltc2941", "lltc,ltc2942" or "lltc,ltc2943" - which also indicates the type of I2C chip attached. +- compatible: Should contain "lltc,ltc2941", "lltc,ltc2942", "lltc,ltc2943" + or "lltc,ltc2944" which also indicates the type of I2C chip attached. - reg: The 7-bit I2C address. - lltc,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 diff --git a/drivers/power/supply/ltc2941-battery-gauge.c b/drivers/power/supply/ltc2941-battery-gauge.c index 42ff4e3..08e4fd9 100644 --- a/drivers/power/supply/ltc2941-battery-gauge.c +++ b/drivers/power/supply/ltc2941-battery-gauge.c @@ -1,6 +1,6 @@ /* - * I2C client/driver for the Linear Technology LTC2941, LTC2942 and LTC2943 - * Battery Gas Gauge IC + * I2C client/driver for the Linear Technology LTC2941, LTC2942, LTC2943 + * and LTC2944 Battery Gas Gauge IC * * Copyright (C) 2014 Topic Embedded Systems * @@ -48,6 +48,7 @@ enum ltc294x_id { LTC2941_ID, LTC2942_ID, LTC2943_ID, + LTC2944_ID, }; #define LTC2941_REG_STATUS_CHIP_ID BIT(7) @@ -153,7 +154,8 @@ static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp) case LTC2942_ID: /* 2942 measures every 2 sec */ control |= LTC2942_REG_CONTROL_MODE_SCAN; break; - case LTC2943_ID: /* 2943 measures every 10 sec */ + case LTC2943_ID: + case LTC2944_ID: /* 2943 and 2944 measure every 10 sec */ control |= LTC2943_REG_CONTROL_MODE_SCAN; break; default: @@ -269,6 +271,11 @@ static int ltc294x_get_voltage(const struct ltc294x_info *info, int *val) value /= 0xFFFF; value *= 1000 / 2; break; + case LTC2944_ID: + value *= 70800 / 5*4; + value /= 0xFFFF; + value *= 1000 * 5/4; + break; default: value *= 6000 * 10; value /= 0xFFFF; @@ -289,10 +296,14 @@ static int ltc294x_get_current(const struct ltc294x_info *info, int *val) LTC2943_REG_CURRENT_MSB, &datar[0], 2); value = (datar[0] << 8) | datar[1]; value -= 0x7FFF; + if (info->id == LTC2944_ID) + value *= 64000; + else + value *= 60000; /* Value is in range -32k..+32k, r_sense is usually 10..50 mOhm, * the formula below keeps everything in s32 range while preserving * enough digits */ - *val = 1000 * ((60000 * value) / (info->r_sense * 0x7FFF)); /* in uA */ + *val = 1000 * (value / (info->r_sense * 0x7FFF)); /* in uA */ return ret; } @@ -470,6 +481,7 @@ static int ltc294x_i2c_probe(struct i2c_client *client, info->supply_desc.type = POWER_SUPPLY_TYPE_BATTERY; info->supply_desc.properties = ltc294x_properties; switch (info->id) { + case LTC2944_ID: case LTC2943_ID: info->supply_desc.num_properties = ARRAY_SIZE(ltc294x_properties); @@ -543,6 +555,7 @@ static const struct i2c_device_id ltc294x_i2c_id[] = { { "ltc2941", LTC2941_ID, }, { "ltc2942", LTC2942_ID, }, { "ltc2943", LTC2943_ID, }, + { "ltc2944", LTC2944_ID, }, { }, }; MODULE_DEVICE_TABLE(i2c, ltc294x_i2c_id); @@ -560,6 +573,10 @@ static const struct of_device_id ltc294x_i2c_of_match[] = { .compatible = "lltc,ltc2943", .data = (void *)LTC2943_ID, }, + { + .compatible = "lltc,ltc2944", + .data = (void *)LTC2944_ID, + }, { }, }; MODULE_DEVICE_TABLE(of, ltc294x_i2c_of_match); @@ -578,5 +595,5 @@ module_i2c_driver(ltc294x_driver); MODULE_AUTHOR("Auryn Verwegen, Topic Embedded Systems"); MODULE_AUTHOR("Mike Looijmans, Topic Embedded Products"); -MODULE_DESCRIPTION("LTC2941/LTC2942/LTC2943 Battery Gas Gauge IC driver"); +MODULE_DESCRIPTION("LTC2941/LTC2942/LTC2943/LTC2944 Battery Gas Gauge IC driver"); MODULE_LICENSE("GPL"); -- 2.7.4