[PATCH v6 1/2] power: act8945a: add charger driver for ACT8945A

Yang, Wenyou Wenyou.Yang at atmel.com
Thu Jan 21 22:42:54 PST 2016


Hi Peter,

Thank you for so much advice.


> -----Original Message-----
> From: Peter Korsgaard [mailto:jacmet at gmail.com] On Behalf Of Peter Korsgaard
> Sent: 2016年1月21日 4:25
> To: Yang, Wenyou <Wenyou.Yang at atmel.com>
> Cc: Sebastian Reichel <sre at kernel.org>; Dmitry Eremin-Solenikov
> <dbaryshkov at gmail.com>; David Woodhouse <dwmw2 at infradead.org>; Rob
> Herring <robh+dt at kernel.org>; Pawel Moll <pawel.moll at arm.com>; Mark
> Rutland <mark.rutland at arm.com>; Ian Campbell <ijc+devicetree at hellion.org.uk>;
> Kumar Gala <galak at codeaurora.org>; Krzysztof Kozlowski
> <k.kozlowski at samsung.com>; Javier Martinez Canillas <javier at dowhile0.org>;
> Lee Jones <lee.jones at linaro.org>; Peter Korsgaard <jacmet at gmail.com>; Ferre,
> Nicolas <Nicolas.FERRE at atmel.com>; linux-arm-kernel at lists.infradead.org;
> linux-kernel at vger.kernel.org; linux-pm at vger.kernel.org
> Subject: Re: [PATCH v6 1/2] power: act8945a: add charger driver for ACT8945A
> 
> >>>>> "Wenyou" == Wenyou Yang <wenyou.yang at atmel.com> 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 at atmel.com>  > ---
> 
>  > 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 at atmel.com>  > + *  > + * 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


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