On 07/16/2017 12:35 PM, Ladislav Michl wrote:
> 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>
Tested-by: Dragos Bogdan <dragos.bogdan@xxxxxxxxxx>
> ---
> 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");
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
