Commit 69fb4dca authored by Hans de Goede's avatar Hans de Goede Committed by Sebastian Reichel
Browse files

power: Add an axp20x-usb-power driver 



This adds a driver for the usb power_supply bits of the axp20x PMICs.

I initially started writing my own driver, before coming aware of
Bruno Prémont's excellent earlier RFC with a driver for this.

My driver was lacking CURRENT_MAX and VOLTAGE_MIN support Bruno's
drvier has, so I've copied the code for those from his driver.

Note that the AC-power-supply and battery charger bits will need separate
drivers. Each one needs its own devictree child-node so that other
devicetree nodes can reference the right power-supply, and thus each one
will get its own mfd-cell / platform_device and platform-driver.

Cc: Bruno Prémont <bonbons@linux-vserver.org>
Acked-by: default avatarLee Jones <lee.jones@linaro.org>
Signed-off-by: default avatarBruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarSebastian Reichel <sre@kernel.org>
parent 26490520

drivers/power/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -472,6 +472,13 @@ config CHARGER_RT9455 
	help

	  Say Y to enable support for Richtek RT9455 battery charger.



config AXP20X_POWER

	tristate "AXP20x power supply driver"

	depends on MFD_AXP20X

	help

	  This driver provides support for the power supply features of

	  AXP20x PMIC.



source "drivers/power/reset/Kconfig"



endif # POWER_SUPPLY

drivers/power/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ obj-$(CONFIG_GENERIC_ADC_BATTERY) += generic-adc-battery.o 


obj-$(CONFIG_PDA_POWER)		+= pda_power.o

obj-$(CONFIG_APM_POWER)		+= apm_power.o

obj-$(CONFIG_AXP20X_POWER)	+= axp20x_usb_power.o

obj-$(CONFIG_MAX8925_POWER)	+= max8925_power.o

obj-$(CONFIG_WM831X_BACKUP)	+= wm831x_backup.o

obj-$(CONFIG_WM831X_POWER)	+= wm831x_power.o

drivers/power/axp20x_usb_power.c

0 → 100644
+248 −0
Original line number Diff line number Diff line 
/*

 * AXP20x PMIC USB power supply status driver

 *

 * Copyright (C) 2015 Hans de Goede <hdegoede@redhat.com>

 * Copyright (C) 2014 Bruno Prémont <bonbons@linux-vserver.org>

 *

 * 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.

 */



#include <linux/device.h>

#include <linux/init.h>

#include <linux/interrupt.h>

#include <linux/kernel.h>

#include <linux/mfd/axp20x.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/power_supply.h>

#include <linux/regmap.h>

#include <linux/slab.h>



#define DRVNAME "axp20x-usb-power-supply"



#define AXP20X_PWR_STATUS_VBUS_PRESENT	BIT(5)

#define AXP20X_PWR_STATUS_VBUS_USED	BIT(4)



#define AXP20X_USB_STATUS_VBUS_VALID	BIT(2)



#define AXP20X_VBUS_VHOLD_uV(b)		(4000000 + (((b) >> 3) & 7) * 100000)

#define AXP20X_VBUS_CLIMIT_MASK		3

#define AXP20X_VBUC_CLIMIT_900mA	0

#define AXP20X_VBUC_CLIMIT_500mA	1

#define AXP20X_VBUC_CLIMIT_100mA	2

#define AXP20X_VBUC_CLIMIT_NONE		3



#define AXP20X_ADC_EN1_VBUS_CURR	BIT(2)

#define AXP20X_ADC_EN1_VBUS_VOLT	BIT(3)



#define AXP20X_VBUS_MON_VBUS_VALID	BIT(3)



struct axp20x_usb_power {

	struct regmap *regmap;

	struct power_supply *supply;

};



static irqreturn_t axp20x_usb_power_irq(int irq, void *devid)

{

	struct axp20x_usb_power *power = devid;



	power_supply_changed(power->supply);



	return IRQ_HANDLED;

}



static int axp20x_usb_power_get_property(struct power_supply *psy,

	enum power_supply_property psp, union power_supply_propval *val)

{

	struct axp20x_usb_power *power = power_supply_get_drvdata(psy);

	unsigned int input, v;

	int ret;



	switch (psp) {

	case POWER_SUPPLY_PROP_VOLTAGE_MIN:

		ret = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);

		if (ret)

			return ret;



		val->intval = AXP20X_VBUS_VHOLD_uV(v);

		return 0;

	case POWER_SUPPLY_PROP_VOLTAGE_NOW:

		ret = axp20x_read_variable_width(power->regmap,

						 AXP20X_VBUS_V_ADC_H, 12);

		if (ret < 0)

			return ret;



		val->intval = ret * 1700; /* 1 step = 1.7 mV */

		return 0;

	case POWER_SUPPLY_PROP_CURRENT_MAX:

		ret = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);

		if (ret)

			return ret;



		switch (v & AXP20X_VBUS_CLIMIT_MASK) {

		case AXP20X_VBUC_CLIMIT_100mA:

			val->intval = 100000;

			break;

		case AXP20X_VBUC_CLIMIT_500mA:

			val->intval = 500000;

			break;

		case AXP20X_VBUC_CLIMIT_900mA:

			val->intval = 900000;

			break;

		case AXP20X_VBUC_CLIMIT_NONE:

			val->intval = -1;

			break;

		}

		return 0;

	case POWER_SUPPLY_PROP_CURRENT_NOW:

		ret = axp20x_read_variable_width(power->regmap,

						 AXP20X_VBUS_I_ADC_H, 12);

		if (ret < 0)

			return ret;



		val->intval = ret * 375; /* 1 step = 0.375 mA */

		return 0;

	default:

		break;

	}



	/* All the properties below need the input-status reg value */

	ret = regmap_read(power->regmap, AXP20X_PWR_INPUT_STATUS, &input);

	if (ret)

		return ret;



	switch (psp) {

	case POWER_SUPPLY_PROP_HEALTH:

		if (!(input & AXP20X_PWR_STATUS_VBUS_PRESENT)) {

			val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;

			break;

		}



		ret = regmap_read(power->regmap, AXP20X_USB_OTG_STATUS, &v);

		if (ret)

			return ret;



		if (!(v & AXP20X_USB_STATUS_VBUS_VALID)) {

			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;

			break;

		}



		val->intval = POWER_SUPPLY_HEALTH_GOOD;

		break;

	case POWER_SUPPLY_PROP_PRESENT:

		val->intval = !!(input & AXP20X_PWR_STATUS_VBUS_PRESENT);

		break;

	case POWER_SUPPLY_PROP_ONLINE:

		val->intval = !!(input & AXP20X_PWR_STATUS_VBUS_USED);

		break;

	default:

		return -EINVAL;

	}



	return 0;

}



static enum power_supply_property axp20x_usb_power_properties[] = {

	POWER_SUPPLY_PROP_HEALTH,

	POWER_SUPPLY_PROP_PRESENT,

	POWER_SUPPLY_PROP_ONLINE,

	POWER_SUPPLY_PROP_VOLTAGE_MIN,

	POWER_SUPPLY_PROP_VOLTAGE_NOW,

	POWER_SUPPLY_PROP_CURRENT_MAX,

	POWER_SUPPLY_PROP_CURRENT_NOW,

};



static const struct power_supply_desc axp20x_usb_power_desc = {

	.name = "axp20x-usb",

	.type = POWER_SUPPLY_TYPE_USB,

	.properties = axp20x_usb_power_properties,

	.num_properties = ARRAY_SIZE(axp20x_usb_power_properties),

	.get_property = axp20x_usb_power_get_property,

};



static int axp20x_usb_power_probe(struct platform_device *pdev)

{

	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);

	struct power_supply_config psy_cfg = {};

	struct axp20x_usb_power *power;

	static const char * const irq_names[] = { "VBUS_PLUGIN",

		"VBUS_REMOVAL", "VBUS_VALID", "VBUS_NOT_VALID" };

	int i, irq, ret;



	if (!of_device_is_available(pdev->dev.of_node))

		return -ENODEV;



	if (!axp20x) {

		dev_err(&pdev->dev, "Parent drvdata not set\n");

		return -EINVAL;

	}



	power = devm_kzalloc(&pdev->dev, sizeof(*power), GFP_KERNEL);

	if (!power)

		return -ENOMEM;



	power->regmap = axp20x->regmap;



	/* Enable vbus valid checking */

	ret = regmap_update_bits(power->regmap, AXP20X_VBUS_MON,

		    AXP20X_VBUS_MON_VBUS_VALID, AXP20X_VBUS_MON_VBUS_VALID);

	if (ret)

		return ret;



	/* Enable vbus voltage and current measurement */

	ret = regmap_update_bits(power->regmap, AXP20X_ADC_EN1,

			AXP20X_ADC_EN1_VBUS_CURR | AXP20X_ADC_EN1_VBUS_VOLT,

			AXP20X_ADC_EN1_VBUS_CURR | AXP20X_ADC_EN1_VBUS_VOLT);

	if (ret)

		return ret;



	psy_cfg.of_node = pdev->dev.of_node;

	psy_cfg.drv_data = power;



	power->supply = devm_power_supply_register(&pdev->dev,

					&axp20x_usb_power_desc, &psy_cfg);

	if (IS_ERR(power->supply))

		return PTR_ERR(power->supply);



	/* Request irqs after registering, as irqs may trigger immediately */

	for (i = 0; i < ARRAY_SIZE(irq_names); i++) {

		irq = platform_get_irq_byname(pdev, irq_names[i]);

		if (irq < 0) {

			dev_warn(&pdev->dev, "No IRQ for %s: %d\n",

				 irq_names[i], irq);

			continue;

		}

		irq = regmap_irq_get_virq(axp20x->regmap_irqc, irq);

		ret = devm_request_any_context_irq(&pdev->dev, irq,

				axp20x_usb_power_irq, 0, DRVNAME, power);

		if (ret < 0)

			dev_warn(&pdev->dev, "Error requesting %s IRQ: %d\n",

				 irq_names[i], ret);

	}



	return 0;

}



static const struct of_device_id axp20x_usb_power_match[] = {

	{ .compatible = "x-powers,axp202-usb-power-supply" },

	{ }

};

MODULE_DEVICE_TABLE(of, axp20x_usb_power_match);



static struct platform_driver axp20x_usb_power_driver = {

	.probe = axp20x_usb_power_probe,

	.driver = {

		.name = DRVNAME,

		.of_match_table = axp20x_usb_power_match,

	},

};



module_platform_driver(axp20x_usb_power_driver);



MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");

MODULE_DESCRIPTION("AXP20x PMIC USB power supply status driver");

MODULE_LICENSE("GPL");

include/linux/mfd/axp20x.h

+24 −0
Original line number Diff line number Diff line
@@ -11,6 +11,8 @@ 
#ifndef __LINUX_MFD_AXP20X_H

#define __LINUX_MFD_AXP20X_H



#include <linux/regmap.h>



enum {

	AXP152_ID = 0,

	AXP202_ID,
@@ -438,4 +440,26 @@ struct axp288_extcon_pdata { 
	struct gpio_desc *gpio_mux_cntl;

};



/* generic helper function for reading 9-16 bit wide regs */

static inline int axp20x_read_variable_width(struct regmap *regmap,

	unsigned int reg, unsigned int width)

{

	unsigned int reg_val, result;

	int err;



	err = regmap_read(regmap, reg, &reg_val);

	if (err)

		return err;



	result = reg_val << (width - 8);



	err = regmap_read(regmap, reg + 1, &reg_val);

	if (err)

		return err;



	result |= reg_val;



	return result;

}



#endif /* __LINUX_MFD_AXP20X_H */

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