RE: [PATCH v6 1/2] power: act8945a: add charger driver for ACT8945A
From: Yang, Wenyou
Date: Fri Jan 22 2016 - 01:43:28 EST
Hi Peter,
Thank you for so much advice.
> -----Original Message-----
> From: Peter Korsgaard [mailto:jacmet@xxxxxxxxx] On Behalf Of Peter Korsgaard
> Sent: 2016年1月21日 4:25
> To: Yang, Wenyou <Wenyou.Yang@xxxxxxxxx>
> Cc: Sebastian Reichel <sre@xxxxxxxxxx>; Dmitry Eremin-Solenikov
> <dbaryshkov@xxxxxxxxx>; David Woodhouse <dwmw2@xxxxxxxxxxxxx>; Rob
> Herring <robh+dt@xxxxxxxxxx>; Pawel Moll <pawel.moll@xxxxxxx>; Mark
> Rutland <mark.rutland@xxxxxxx>; Ian Campbell <ijc+devicetree@xxxxxxxxxxxxxx>;
> Kumar Gala <galak@xxxxxxxxxxxxxx>; Krzysztof Kozlowski
> <k.kozlowski@xxxxxxxxxxx>; Javier Martinez Canillas <javier@xxxxxxxxxxxx>;
> Lee Jones <lee.jones@xxxxxxxxxx>; Peter Korsgaard <jacmet@xxxxxxxxx>; Ferre,
> Nicolas <Nicolas.FERRE@xxxxxxxxx>; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; linux-pm@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v6 1/2] power: act8945a: add charger driver for ACT8945A
>
> >>>>> "Wenyou" == Wenyou Yang <wenyou.yang@xxxxxxxxx> writes:
>
> > 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 v6:
> > - change the type value to unsigned int.
>
> [snip]
>
> > +++ b/drivers/power/act8945a_charger.c
> > @@ -0,0 +1,375 @@
> > +/*
> > + * 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/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 (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 act8945a_dev *act8945a_dev;
>
> I still don't see the point in this struct act8945a_dev instead of just having a
> pointer to a regmap here (more about that later).
>
> > + struct power_supply *psy;
>
> You use devm and only use this in the probe, so not needed.
>
> > +
> > + u32 tolal_time_out;
>
> Typo, should be total_time_out
>
> > + u32 pre_time_out;
> > + u32 input_voltage_threshold;
>
> These 3 parameters are only used to keep track of data between
> _parse_dt() and _charger_config() which you call right after eachother. If you
> merge those two functions then these can be dropped.
Yes, you are right, it is clearer.
>
>
> > + bool battery_temperature;
> > + int chglev_pin;
> > + int chglev_value;
>
> Same for these two.
>
>
> > +};
> > +
> > +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-gpios", 0, &flags);
> > +
> > + charger->chglev_value = (flags == OF_GPIO_ACTIVE_LOW) ? 0 : 1;
> > +
> > + charger->battery_temperature = of_property_read_bool(np,
> > + "active-semi,check-battery-temperature");
> > +
> > + if (of_property_read_u32(np,
> > + "active-semi,input-voltage-threshold-microvolt",
> > + &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;
> > + unsigned int 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);
>
> Never used, so you can drop this.
>
> > +
> > + charger->act8945a_dev = act8945a_dev;
>
> Once again, why can't you just do something like:
>
> charger->regmap = dev_get_regmap(pdev->dev.parent);
>
> And drop this act8945_dev structure?
>
> --
> Bye, Peter Korsgaard
Best Regards,
Wenyou Yang