Re: [PATCH v8 1/2] power: act8945a: add charger driver for ACT8945A

From: Krzysztof Kozlowski
Date: Mon Feb 15 2016 - 02:46:24 EST


On 05.02.2016 13:26, Wenyou Yang wrote:
> This patch adds new driver for Active-semi ACT8945A ActivePath
> charger (part of ACT8945A MFD driver) providing power supply class
> information to userspace.
>
> The driver can be configured through DT (such as, total timer,
> precondition timer and input over-voltage threshold).
>
> Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx>
> ---
>
> Changes in v8:
> - remove the OF table.
> - due to the mfd cell .of_compatible removal, use the platform
> device's parent of_node to read the property and assign it
> to the psy_cfg.of_node.
> - fix the typo.
>
> Changes in v7:
> - use the helper dev_get_regmap(pdev->dev.parent, NULL) to get regmap.
> - remove *act8945a_dev member from struct act8945a_charger.
> - remove *psy member from struct act8945a_charger.
> - merge _parse_dt() and _charger_config() functions, remove relevent
> members from struct act8945a_charger.
> - remove unused platform_set_drvdata(pdev, charger) statement.
>
> Changes in v6:
> - change the type value to unsigned int.
>
> Changes in v5:
> - remove spare spaces after #define.
> - add OF match table.
>
> Changes in v4:
> - use spaces after #define, not tabs.
> - use BIT(n) macros to substitute (0x01 << x).
> - change dt properties with more legible name.
>
> Changes in v3:
> - update the file header with short version license and author line.
> - remove unused member of struct act8945a_charger, dev.
> - action due to removing the member of stuct act8945a_dev, dev.
> - remove the unnecessary print out.
> - remove the unnecessary act8945a_charger_remove().
> - fix align of the code-style.
>
> Changes in v2:
> 1./ Substitute of_property_read_bool() for of_get_property().
> 2./ Substitute devm_power_supply_register() for power_supply_register().
> 3./ Use module_platform_driver(), instead of subsys_initcall().
> 4./ Substitute MODULE_LICENSE("GPL") for MODULE_LICENSE("GPL v2").
>
> drivers/power/Kconfig | 7 +
> drivers/power/Makefile | 1 +
> drivers/power/act8945a_charger.c | 355 ++++++++++++++++++++++++++++++++++++++
> 3 files changed, 363 insertions(+)
> create mode 100644 drivers/power/act8945a_charger.c
>
> diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
> index 1ddd13c..ae75211 100644
> --- a/drivers/power/Kconfig
> +++ b/drivers/power/Kconfig
> @@ -75,6 +75,13 @@ config BATTERY_88PM860X
> help
> Say Y here to enable battery monitor for Marvell 88PM860x chip.
>
> +config BATTERY_ACT8945A
> + tristate "Active-semi ACT8945A charger driver"
> + depends on MFD_ACT8945A
> + help
> + Say Y here to enable support for power supply provided by
> + Active-semi ActivePath ACT8945A charger.
> +
> config BATTERY_DS2760
> tristate "DS2760 battery driver (HP iPAQ & others)"
> depends on W1 && W1_SLAVE_DS2760
> diff --git a/drivers/power/Makefile b/drivers/power/Makefile
> index 0e4eab5..e46b75d 100644
> --- a/drivers/power/Makefile
> +++ b/drivers/power/Makefile
> @@ -17,6 +17,7 @@ obj-$(CONFIG_WM8350_POWER) += wm8350_power.o
> obj-$(CONFIG_TEST_POWER) += test_power.o
>
> obj-$(CONFIG_BATTERY_88PM860X) += 88pm860x_battery.o
> +obj-$(CONFIG_BATTERY_ACT8945A) += act8945a_charger.o
> obj-$(CONFIG_BATTERY_DS2760) += ds2760_battery.o
> obj-$(CONFIG_BATTERY_DS2780) += ds2780_battery.o
> obj-$(CONFIG_BATTERY_DS2781) += ds2781_battery.o
> diff --git a/drivers/power/act8945a_charger.c b/drivers/power/act8945a_charger.c
> new file mode 100644
> index 0000000..0da0ea5
> --- /dev/null
> +++ b/drivers/power/act8945a_charger.c
> @@ -0,0 +1,355 @@
> +/*
> + * Power supply driver for the Active-semi ACT8945A PMIC
> + *
> + * Copyright (C) 2015 Atmel Corporation
> + *
> + * Author: Wenyou Yang <wenyou.yang@xxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + */
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_gpio.h>
> +#include <linux/platform_device.h>
> +#include <linux/power_supply.h>
> +#include <linux/regmap.h>
> +
> +static const char *act8945a_charger_model = "ACT8945A";
> +static const char *act8945a_charger_manufacturer = "Active-semi";
> +
> +/**
> + * ACT8945A Charger Register Map
> + */
> +
> +/* 0x70: Reserved */
> +#define ACT8945A_APCH_CFG 0x71
> +#define ACT8945A_APCH_STATUS 0x78
> +#define ACT8945A_APCH_CTRL 0x79
> +#define ACT8945A_APCH_STATE 0x7A
> +
> +/* ACT8945A_APCH_CFG */
> +#define APCH_CFG_OVPSET (0x3 << 0)
> +#define APCH_CFG_OVPSET_6V6 (0x0 << 0)
> +#define APCH_CFG_OVPSET_7V (0x1 << 0)
> +#define APCH_CFG_OVPSET_7V5 (0x2 << 0)
> +#define APCH_CFG_OVPSET_8V (0x3 << 0)
> +#define APCH_CFG_PRETIMO (0x3 << 2)
> +#define APCH_CFG_PRETIMO_40_MIN (0x0 << 2)
> +#define APCH_CFG_PRETIMO_60_MIN (0x1 << 2)
> +#define APCH_CFG_PRETIMO_80_MIN (0x2 << 2)
> +#define APCH_CFG_PRETIMO_DISABLED (0x3 << 2)
> +#define APCH_CFG_TOTTIMO (0x3 << 4)
> +#define APCH_CFG_TOTTIMO_3_HOUR (0x0 << 4)
> +#define APCH_CFG_TOTTIMO_4_HOUR (0x1 << 4)
> +#define APCH_CFG_TOTTIMO_5_HOUR (0x2 << 4)
> +#define APCH_CFG_TOTTIMO_DISABLED (0x3 << 4)
> +#define APCH_CFG_SUSCHG (0x1 << 7)
> +
> +#define APCH_STATUS_CHGDAT BIT(0)
> +#define APCH_STATUS_INDAT BIT(1)
> +#define APCH_STATUS_TEMPDAT BIT(2)
> +#define APCH_STATUS_TIMRDAT BIT(3)
> +#define APCH_STATUS_CHGSTAT BIT(4)
> +#define APCH_STATUS_INSTAT BIT(5)
> +#define APCH_STATUS_TEMPSTAT BIT(6)
> +#define APCH_STATUS_TIMRSTAT BIT(7)
> +
> +#define APCH_CTRL_CHGEOCOUT BIT(0)
> +#define APCH_CTRL_INDIS BIT(1)
> +#define APCH_CTRL_TEMPOUT BIT(2)
> +#define APCH_CTRL_TIMRPRE BIT(3)
> +#define APCH_CTRL_CHGEOCIN BIT(4)
> +#define APCH_CTRL_INCON BIT(5)
> +#define APCH_CTRL_TEMPIN BIT(6)
> +#define APCH_CTRL_TIMRTOT BIT(7)
> +
> +#define APCH_STATE_ACINSTAT (0x1 << 1)
> +#define APCH_STATE_CSTATE (0x3 << 4)
> +#define APCH_STATE_CSTATE_SHIFT 4
> +#define APCH_STATE_CSTATE_DISABLED 0x00
> +#define APCH_STATE_CSTATE_EOC 0x01
> +#define APCH_STATE_CSTATE_FAST 0x02
> +#define APCH_STATE_CSTATE_PRE 0x03
> +
> +struct act8945a_charger {
> + struct regmap *regmap;
> + bool battery_temperature;
> +};
> +
> +static int act8945a_get_charger_state(struct regmap *regmap, int *val)
> +{
> + int ret;
> + unsigned int status, state;
> +
> + ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
> + if (ret < 0)
> + return ret;
> +
> + ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
> + if (ret < 0)
> + return ret;
> +
> + state &= APCH_STATE_CSTATE;
> + state >>= APCH_STATE_CSTATE_SHIFT;
> +
> + if (state == APCH_STATE_CSTATE_EOC) {
> + if (status & APCH_STATUS_CHGDAT)
> + *val = POWER_SUPPLY_STATUS_FULL;
> + else
> + *val = POWER_SUPPLY_STATUS_NOT_CHARGING;
> + } else if ((state == APCH_STATE_CSTATE_FAST) ||
> + (state == APCH_STATE_CSTATE_PRE)) {
> + *val = POWER_SUPPLY_STATUS_CHARGING;
> + } else {
> + *val = POWER_SUPPLY_STATUS_NOT_CHARGING;
> + }
> +
> + return 0;
> +}
> +
> +static int act8945a_get_charge_type(struct regmap *regmap, int *val)
> +{
> + int ret;
> + unsigned int state;
> +
> + ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
> + if (ret < 0)
> + return ret;
> +
> + state &= APCH_STATE_CSTATE;
> + state >>= APCH_STATE_CSTATE_SHIFT;
> +
> + switch (state) {
> + case APCH_STATE_CSTATE_PRE:
> + *val = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
> + break;
> + case APCH_STATE_CSTATE_FAST:
> + *val = POWER_SUPPLY_CHARGE_TYPE_FAST;
> + break;
> + case APCH_STATE_CSTATE_EOC:
> + case APCH_STATE_CSTATE_DISABLED:
> + default:
> + *val = POWER_SUPPLY_CHARGE_TYPE_NONE;
> + }
> +
> + return 0;
> +}
> +
> +static int act8945a_get_battery_health(struct act8945a_charger *charger,
> + struct regmap *regmap, int *val)
> +{
> + int ret;
> + unsigned int status;
> +
> + ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
> + if (ret < 0)
> + return ret;
> +
> + if (charger->battery_temperature && !(status & APCH_STATUS_TEMPDAT))
> + *val = POWER_SUPPLY_HEALTH_OVERHEAT;
> + else if (!(status & APCH_STATUS_INDAT))
> + *val = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
> + else if (status & APCH_STATUS_TIMRDAT)
> + *val = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
> + else
> + *val = POWER_SUPPLY_HEALTH_GOOD;
> +
> + return 0;
> +}
> +
> +static enum power_supply_property act8945a_charger_props[] = {
> + POWER_SUPPLY_PROP_STATUS,
> + POWER_SUPPLY_PROP_CHARGE_TYPE,
> + POWER_SUPPLY_PROP_TECHNOLOGY,
> + POWER_SUPPLY_PROP_HEALTH,
> + POWER_SUPPLY_PROP_MODEL_NAME,
> + POWER_SUPPLY_PROP_MANUFACTURER
> +};
> +
> +static int act8945a_charger_get_property(struct power_supply *psy,
> + enum power_supply_property prop,
> + union power_supply_propval *val)
> +{
> + struct act8945a_charger *charger = power_supply_get_drvdata(psy);
> + struct regmap *regmap = charger->regmap;
> + int ret = 0;
> +
> + switch (prop) {
> + case POWER_SUPPLY_PROP_STATUS:
> + ret = act8945a_get_charger_state(regmap, &val->intval);
> + break;
> + case POWER_SUPPLY_PROP_CHARGE_TYPE:
> + ret = act8945a_get_charge_type(regmap, &val->intval);
> + break;
> + case POWER_SUPPLY_PROP_TECHNOLOGY:
> + val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
> + break;
> + case POWER_SUPPLY_PROP_HEALTH:
> + ret = act8945a_get_battery_health(charger,
> + regmap, &val->intval);
> + break;
> + case POWER_SUPPLY_PROP_MODEL_NAME:
> + val->strval = act8945a_charger_model;
> + break;
> + case POWER_SUPPLY_PROP_MANUFACTURER:
> + val->strval = act8945a_charger_manufacturer;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return ret;
> +}
> +
> +static const struct power_supply_desc act8945a_charger_desc = {
> + .name = "act8945a-charger",
> + .type = POWER_SUPPLY_TYPE_BATTERY,
> + .get_property = act8945a_charger_get_property,
> + .properties = act8945a_charger_props,
> + .num_properties = ARRAY_SIZE(act8945a_charger_props),
> +};
> +
> +#define DEFAULT_TOTAL_TIME_OUT 3
> +#define DEFAULT_PRE_TIME_OUT 40
> +#define DEFAULT_INPUT_OVP_THRESHOLD 6600
> +
> +static int act8945a_charger_config(struct device *dev,
> + struct act8945a_charger *charger)
> +{
> + struct device_node *np = dev->of_node;
> + enum of_gpio_flags flags;
> + struct regmap *regmap = charger->regmap;
> +
> + u32 total_time_out;
> + u32 pre_time_out;
> + u32 input_voltage_threshold;
> + int chglev_pin;
> +
> + unsigned int value = 0;
> +
> + if (!np) {
> + dev_err(dev, "no charger of node\n");
> + return -EINVAL;
> + }
> +
> + charger->battery_temperature = of_property_read_bool(np,
> + "active-semi,check-battery-temperature");
> +
> + chglev_pin = of_get_named_gpio_flags(np,
> + "active-semi,chglev-gpios", 0, &flags);
> +
> + if (gpio_is_valid(chglev_pin)) {
> + gpio_set_value(chglev_pin,
> + ((flags == OF_GPIO_ACTIVE_LOW) ? 0 : 1));
> + }
> +
> + if (of_property_read_u32(np,
> + "active-semi,input-voltage-threshold-microvolt",
> + &input_voltage_threshold))
> + input_voltage_threshold = DEFAULT_INPUT_OVP_THRESHOLD;
> +
> + if (of_property_read_u32(np,
> + "active-semi,precondition-timeout",
> + &pre_time_out))
> + pre_time_out = DEFAULT_PRE_TIME_OUT;
> +
> + if (of_property_read_u32(np, "active-semi,total-timeout",
> + &total_time_out))
> + total_time_out = DEFAULT_TOTAL_TIME_OUT;
> +
> + switch (input_voltage_threshold) {
> + case 8000:
> + value |= APCH_CFG_OVPSET_8V;
> + break;
> + case 7500:
> + value |= APCH_CFG_OVPSET_7V5;
> + break;
> + case 7000:
> + value |= APCH_CFG_OVPSET_7V;
> + break;
> + case 6600:
> + default:
> + value |= APCH_CFG_OVPSET_6V6;
> + break;
> + }
> +
> + switch (pre_time_out) {
> + case 60:
> + value |= APCH_CFG_PRETIMO_60_MIN;
> + break;
> + case 80:
> + value |= APCH_CFG_PRETIMO_80_MIN;
> + break;
> + case 0:
> + value |= APCH_CFG_PRETIMO_DISABLED;
> + break;
> + case 40:
> + default:
> + value |= APCH_CFG_PRETIMO_40_MIN;
> + break;
> + }
> +
> + switch (total_time_out) {
> + case 4:
> + value |= APCH_CFG_TOTTIMO_4_HOUR;
> + break;
> + case 5:
> + value |= APCH_CFG_TOTTIMO_5_HOUR;
> + break;
> + case 0:
> + value |= APCH_CFG_TOTTIMO_DISABLED;
> + break;
> + case 3:
> + default:
> + value |= APCH_CFG_TOTTIMO_3_HOUR;
> + break;
> + }
> +
> + return regmap_write(regmap, ACT8945A_APCH_CFG, value);
> +}
> +
> +static int act8945a_charger_probe(struct platform_device *pdev)
> +{
> + struct act8945a_charger *charger;
> + struct power_supply *psy;
> + struct power_supply_config psy_cfg = {};
> + int ret;
> +
> + charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
> + if (!charger)
> + return -ENOMEM;
> +
> + charger->regmap = dev_get_regmap(pdev->dev.parent, NULL);

I think it would be good (as a precaution) to check for non-null here:
if (!charger->regmap) {
dev_err(... "Parent did not provide regmap\n");
return -EINVAL;
}

Beside that:

Reviewed-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>

Best regards,
Krzysztof