From: Dragos Bogdan <dragos.bogdan@xxxxxxxxxx>
LTC2944 is compatible with LTC2943, but uses different
voltage and current computing constants.
Signed-off-by: Dragos Bogdan <dragos.bogdan@xxxxxxxxxx>
Signed-off-by: Ladislav Michl <ladis@xxxxxxxxxxxxxx>
---
Changes:
- v2: fixed voltage and current conversion
- v3: skipped
- v4: skipped
- v5: fixed voltage conversion overflow, rebased on LTC2942 patchset
- v6: fix missing break in the switch statement
.../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 8ec10366295d..3b9ba147b041 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 42ff4e3daf35..08e4fd9ee607 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");
--
2.11.0
--
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