Commit fb24ccfb authored by Artur Rojek's avatar Artur Rojek Committed by Sebastian Reichel
Browse files

power: supply: add Ingenic JZ47xx battery driver. 



Add a driver for battery present on Ingenic JZ47xx SoCs.

Signed-off-by: default avatarArtur Rojek <contact@artur-rojek.eu>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: default avatarSebastian Reichel <sebastian.reichel@collabora.com>
parent bbdfeea2

drivers/power/supply/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -169,6 +169,17 @@ config BATTERY_COLLIE 
	  Say Y to enable support for the battery on the Sharp Zaurus

	  SL-5500 (collie) models.



config BATTERY_INGENIC

	tristate "Ingenic JZ47xx SoCs battery driver"

	depends on MIPS || COMPILE_TEST

	depends on INGENIC_ADC

	help

	  Choose this option if you want to monitor battery status on

	  Ingenic JZ47xx SoC based devices.



	  This driver can also be built as a module. If so, the module will be

	  called ingenic-battery.



config BATTERY_IPAQ_MICRO

	tristate "iPAQ Atmel Micro ASIC battery driver"

	depends on MFD_IPAQ_MICRO

drivers/power/supply/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ obj-$(CONFIG_BATTERY_PMU) += pmu_battery.o 
obj-$(CONFIG_BATTERY_OLPC)	+= olpc_battery.o

obj-$(CONFIG_BATTERY_TOSA)	+= tosa_battery.o

obj-$(CONFIG_BATTERY_COLLIE)	+= collie_battery.o

obj-$(CONFIG_BATTERY_INGENIC)	+= ingenic-battery.o

obj-$(CONFIG_BATTERY_IPAQ_MICRO) += ipaq_micro_battery.o

obj-$(CONFIG_BATTERY_WM97XX)	+= wm97xx_battery.o

obj-$(CONFIG_BATTERY_SBS)	+= sbs-battery.o

drivers/power/supply/ingenic-battery.c

0 → 100644
+184 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Battery driver for the Ingenic JZ47xx SoCs

 * Copyright (c) 2019 Artur Rojek <contact@artur-rojek.eu>

 *

 * based on drivers/power/supply/jz4740-battery.c

 */



#include <linux/iio/consumer.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/power_supply.h>

#include <linux/property.h>



struct ingenic_battery {

	struct device *dev;

	struct iio_channel *channel;

	struct power_supply_desc desc;

	struct power_supply *battery;

	struct power_supply_battery_info info;

};



static int ingenic_battery_get_property(struct power_supply *psy,

					enum power_supply_property psp,

					union power_supply_propval *val)

{

	struct ingenic_battery *bat = power_supply_get_drvdata(psy);

	struct power_supply_battery_info *info = &bat->info;

	int ret;



	switch (psp) {

	case POWER_SUPPLY_PROP_HEALTH:

		ret = iio_read_channel_processed(bat->channel, &val->intval);

		val->intval *= 1000;

		if (val->intval < info->voltage_min_design_uv)

			val->intval = POWER_SUPPLY_HEALTH_DEAD;

		else if (val->intval > info->voltage_max_design_uv)

			val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;

		else

			val->intval = POWER_SUPPLY_HEALTH_GOOD;

		return ret;

	case POWER_SUPPLY_PROP_VOLTAGE_NOW:

		ret = iio_read_channel_processed(bat->channel, &val->intval);

		val->intval *= 1000;

		return ret;

	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:

		val->intval = info->voltage_min_design_uv;

		return 0;

	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:

		val->intval = info->voltage_max_design_uv;

		return 0;

	default:

		return -EINVAL;

	};

}



/* Set the most appropriate IIO channel voltage reference scale

 * based on the battery's max voltage.

 */

static int ingenic_battery_set_scale(struct ingenic_battery *bat)

{

	const int *scale_raw;

	int scale_len, scale_type, best_idx = -1, best_mV, max_raw, i, ret;

	u64 max_mV;



	ret = iio_read_max_channel_raw(bat->channel, &max_raw);

	if (ret) {

		dev_err(bat->dev, "Unable to read max raw channel value\n");

		return ret;

	}



	ret = iio_read_avail_channel_attribute(bat->channel, &scale_raw,

					       &scale_type, &scale_len,

					       IIO_CHAN_INFO_SCALE);

	if (ret < 0) {

		dev_err(bat->dev, "Unable to read channel avail scale\n");

		return ret;

	}

	if (ret != IIO_AVAIL_LIST || scale_type != IIO_VAL_FRACTIONAL_LOG2)

		return -EINVAL;



	max_mV = bat->info.voltage_max_design_uv / 1000;



	for (i = 0; i < scale_len; i += 2) {

		u64 scale_mV = (max_raw * scale_raw[i]) >> scale_raw[i + 1];



		if (scale_mV < max_mV)

			continue;



		if (best_idx >= 0 && scale_mV > best_mV)

			continue;



		best_mV = scale_mV;

		best_idx = i;

	}



	if (best_idx < 0) {

		dev_err(bat->dev, "Unable to find matching voltage scale\n");

		return -EINVAL;

	}



	return iio_write_channel_attribute(bat->channel,

					   scale_raw[best_idx],

					   scale_raw[best_idx + 1],

					   IIO_CHAN_INFO_SCALE);

}



static enum power_supply_property ingenic_battery_properties[] = {

	POWER_SUPPLY_PROP_HEALTH,

	POWER_SUPPLY_PROP_VOLTAGE_NOW,

	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,

	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,

};



static int ingenic_battery_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct ingenic_battery *bat;

	struct power_supply_config psy_cfg = {};

	struct power_supply_desc *desc;

	int ret;



	bat = devm_kzalloc(dev, sizeof(*bat), GFP_KERNEL);

	if (!bat)

		return -ENOMEM;



	bat->dev = dev;

	bat->channel = devm_iio_channel_get(dev, "battery");

	if (IS_ERR(bat->channel))

		return PTR_ERR(bat->channel);



	desc = &bat->desc;

	desc->name = "jz-battery";

	desc->type = POWER_SUPPLY_TYPE_BATTERY;

	desc->properties = ingenic_battery_properties;

	desc->num_properties = ARRAY_SIZE(ingenic_battery_properties);

	desc->get_property = ingenic_battery_get_property;

	psy_cfg.drv_data = bat;

	psy_cfg.of_node = dev->of_node;



	bat->battery = devm_power_supply_register(dev, desc, &psy_cfg);

	if (IS_ERR(bat->battery)) {

		dev_err(dev, "Unable to register battery\n");

		return PTR_ERR(bat->battery);

	}



	ret = power_supply_get_battery_info(bat->battery, &bat->info);

	if (ret) {

		dev_err(dev, "Unable to get battery info: %d\n", ret);

		return ret;

	}

	if (bat->info.voltage_min_design_uv < 0) {

		dev_err(dev, "Unable to get voltage min design\n");

		return bat->info.voltage_min_design_uv;

	}

	if (bat->info.voltage_max_design_uv < 0) {

		dev_err(dev, "Unable to get voltage max design\n");

		return bat->info.voltage_max_design_uv;

	}



	return ingenic_battery_set_scale(bat);

}



#ifdef CONFIG_OF

static const struct of_device_id ingenic_battery_of_match[] = {

	{ .compatible = "ingenic,jz4740-battery", },

	{ },

};

MODULE_DEVICE_TABLE(of, ingenic_battery_of_match);

#endif



static struct platform_driver ingenic_battery_driver = {

	.driver = {

		.name = "ingenic-battery",

		.of_match_table = of_match_ptr(ingenic_battery_of_match),

	},

	.probe = ingenic_battery_probe,

};

module_platform_driver(ingenic_battery_driver);



MODULE_DESCRIPTION("Battery driver for Ingenic JZ47xx SoCs");

MODULE_AUTHOR("Artur Rojek <contact@artur-rojek.eu>");

MODULE_LICENSE("GPL");

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