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

[Krzysztof Kozlowski <k.kozlowski@samsung.com>]

2016-01-08 11:13 GMT+09:00 Wenyou Yang <wenyou.yang@atmel.com>:
> 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 is configured through DTS (battery and system related
> settings) and sysfs entries (timers and input over-voltage threshold).
>
> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
> ---
>
>  drivers/power/Kconfig            |    7 +
>  drivers/power/Makefile           |    1 +
>  drivers/power/act8945a_charger.c |  397 ++++++++++++++++++++++++++++++++++++++
>  3 files changed, 405 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..5b55cd7
> --- /dev/null
> +++ b/drivers/power/act8945a_charger.c
> @@ -0,0 +1,397 @@
> +/*
> + * Power supply driver for the Active-semi ACT8945A PMIC
> + *
> + * Copyright (C) 2015 Atmel Corporation
> + *                   Wenyou Yang <wenyou.yang@atmel.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/mfd/act8945a.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                (0x03 << 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       (0x03 << 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       (0x03 << 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                (0x01 << 7)
> +
> +#define APCH_STATUS_CHGDAT     (0x01 << 0)
> +#define APCH_STATUS_INDAT      (0x01 << 1)
> +#define APCH_STATUS_TEMPDAT    (0x01 << 2)
> +#define APCH_STATUS_TIMRDAT    (0x01 << 3)
> +#define APCH_STATUS_CHGSTAT    (0x01 << 4)
> +#define APCH_STATUS_INSTAT     (0x01 << 5)
> +#define APCH_STATUS_TEMPSTAT   (0x01 << 6)
> +#define APCH_STATUS_TIMRSTAT   (0x01 << 7)
> +
> +#define APCH_CTRL_CHGEOCOUT    (0x01 << 0)
> +#define APCH_CTRL_INDIS                (0x01 << 1)
> +#define APCH_CTRL_TEMPOUT      (0x01 << 2)
> +#define APCH_CTRL_TIMRPRE      (0x01 << 3)
> +#define APCH_CTRL_CHGEOCIN     (0x01 << 4)
> +#define APCH_CTRL_INCON                (0x01 << 5)
> +#define APCH_CTRL_TEMPIN       (0x01 << 6)
> +#define APCH_CTRL_TIMRTOT      (0x01 << 7)
> +
> +#define APCH_STATE_ACINSTAT    (0x01 << 1)
> +#define APCH_STATE_CSTATE      (0x03 << 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 device *dev;
> +       struct act8945a_dev *act8945a_dev;
> +       struct power_supply *psy;
> +
> +       u32 tolal_time_out;
> +       u32 pre_time_out;
> +       u32 input_voltage_threshold;
> +       bool battery_temperature;
> +       int chglev_pin;
> +       int chglev_value;
> +};
> +
> +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->act8945a_dev->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_parse_dt(struct device *dev,
> +                                   struct act8945a_charger *charger)
> +{
> +       struct device_node *np = dev->of_node;
> +       enum of_gpio_flags flags;
> +
> +       if (!np) {
> +               dev_err(dev, "no charger of node\n");
> +               return -EINVAL;
> +       }
> +
> +       charger->chglev_pin = of_get_named_gpio_flags(np,
> +                               "active-semi,chglev-gpio", 0, &flags);
> +
> +       charger->chglev_value = (flags == OF_GPIO_ACTIVE_LOW) ? 0 : 1;
> +
> +       charger->battery_temperature = !!of_get_property(np,
> +                               "active-semi,battery_temperature", NULL);

Just: of_property_read_bool()?

> +
> +       if (of_property_read_u32(np, "active-semi,input_voltage_threshold",
> +                                &charger->input_voltage_threshold))
> +               charger->input_voltage_threshold = DEFAULT_PRE_TIME_OUT;
> +
> +       if (of_property_read_u32(np, "active-semi,precondition_timeout",
> +                                &charger->pre_time_out))
> +               charger->pre_time_out = DEFAULT_PRE_TIME_OUT;
> +
> +       if (of_property_read_u32(np, "active-semi,total_timeout",
> +                                &charger->tolal_time_out))
> +               charger->tolal_time_out = DEFAULT_TOTAL_TIME_OUT;
> +
> +       return 0;
> +}
> +
> +static int act8945a_charger_config(struct act8945a_charger *charger)
> +{
> +       struct regmap *regmap = charger->act8945a_dev->regmap;
> +       u8 value = 0;
> +
> +       if (gpio_is_valid(charger->chglev_pin))
> +               gpio_set_value(charger->chglev_pin, charger->chglev_value);
> +
> +       switch (charger->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 (charger->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 (charger->tolal_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_dev *act8945a_dev = dev_get_drvdata(pdev->dev.parent);
> +       struct act8945a_charger *charger;
> +       struct power_supply_config psy_cfg = {};
> +       int ret;
> +
> +       charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
> +       if (!charger)
> +               return -ENOMEM;
> +
> +       platform_set_drvdata(pdev, charger);
> +
> +       charger->dev = &pdev->dev;
> +       charger->act8945a_dev = act8945a_dev;
> +
> +       ret = act8945a_charger_parse_dt(&pdev->dev, charger);
> +       if (ret)
> +               return ret;
> +
> +       ret = act8945a_charger_config(charger);
> +       if (ret)
> +               return ret;
> +
> +       psy_cfg.of_node = pdev->dev.of_node;
> +       psy_cfg.drv_data = charger;
> +
> +       charger->psy = power_supply_register(&pdev->dev,
> +                                            &act8945a_charger_desc,
> +                                            &psy_cfg);

You can use devm-like() API for this and get rid of remove function...
but it is not a necessity I think. Up to you.

> +       if (IS_ERR(charger->psy)) {
> +               dev_err(act8945a_dev->dev, "failed to register power supply\n");
> +               return PTR_ERR(charger->psy);
> +       }
> +
> +       dev_info(act8945a_dev->dev, "charger driver registered\n");
> +
> +       return 0;
> +}
> +
> +static int act8945a_charger_remove(struct platform_device *pdev)
> +{
> +       struct act8945a_charger *charger = platform_get_drvdata(pdev);
> +
> +       power_supply_unregister(charger->psy);
> +
> +       return 0;
> +}
> +
> +static struct platform_driver act8945a_charger_driver = {
> +       .driver = {
> +               .name = "act8945a-charger",
> +       },
> +       .probe  = act8945a_charger_probe,
> +       .remove = act8945a_charger_remove,
> +};
> +
> +static int __init act8945a_charger_init(void)
> +{
> +       return platform_driver_register(&act8945a_charger_driver);
> +}
> +subsys_initcall(act8945a_charger_init);

Why subsys_initcall? This should be regular module_platform_driver.

> +
> +static void __exit act8945a_charger_cleanup(void)
> +{
> +       platform_driver_unregister(&act8945a_charger_driver);
> +}
> +module_exit(act8945a_charger_cleanup);
> +
> +MODULE_DESCRIPTION("Active-semi ACT8945A ActivePath charger driver");
> +MODULE_AUTHOR("Wenyou Yang <wenyou.yang@atmel.com>");
> +MODULE_LICENSE("GPL v2");

In the comment at beginning you mentioned GPL v2+ so this should be "GPL".

Best regards,
Krzysztof