Re: [PATCH] power: battery: Generic battery driver using IIO

Jonathan Cameron
2012-09-13T20:39:29Z

On 09/13/2012 05:16 PM, anish kumar wrote:
> From: anish kumar <anish198519851985@gmail.com>
>
> In this version:
> Addressed concerns raised by lars:
> a. made the adc_bat per device.
> b. get the IIO channel using hardcoded channel names.
Couple of bits related to this inline..

> c. Minor issues related to gpio_is_valid and some code
> refactoring.
>
> Signed-off-by: anish kumar <anish198519851985@gmail.com>
> ---
> drivers/power/generic-adc-battery.c | 460 +++++++++++++++++++++++++++++
> include/linux/power/generic-adc-battery.h | 33 ++
> 2 files changed, 493 insertions(+), 0 deletions(-)
> create mode 100644 drivers/power/generic-adc-battery.c
> create mode 100644 include/linux/power/generic-adc-battery.h
>
> diff --git a/drivers/power/generic-adc-battery.c b/drivers/power/generic-adc-battery.c
> new file mode 100644
> index 0000000..003e0e1
> --- /dev/null
> +++ b/drivers/power/generic-adc-battery.c
> @@ -0,0 +1,460 @@
> +/*
> + * Generic battery driver code using IIO
> + * Copyright (C) 2012, Anish Kumar <anish198519851985@gmail.com>
> + * based on jz4740-battery.c
> + * based on s3c_adc_battery.c
> + *
> + * This file is subject to the terms and conditions of the GNU General Public
> + * License. See the file COPYING in the main directory of this archive for
> + * more details.
> + *
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/power_supply.h>
> +#include <linux/gpio.h>
> +#include <linux/err.h>
> +#include <linux/timer.h>
> +#include <linux/jiffies.h>
> +#include <linux/errno.h>
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/iio/consumer.h>
> +#include <linux/iio/types.h>
> +
> +#include <linux/power/generic-adc-battery.h>
> +
> +#define to_generic_bat(ptr) \
> + container_of(ptr, struct generic_adc_bat, ptr)
> +
> +enum chan_type {
> + VOLTAGE = 0,
> + CURRENT,
> + POWER,
> + MAX_CHAN_TYPE
> +};
> +
> +#define CHAN_MAX_NAME 30
> +/*
> + * channel_name suggests the standard channel names for commonly used
> + * channel types.
> + */
const
> +char channel_name[][CHAN_MAX_NAME + 1] = {
> + [VOLTAGE] = "voltage",
> + [CURRENT] = "current",
> + [POWER] = "power",
> +};
> +
> +struct generic_adc_bat {
> + struct power_supply psy;
> + struct iio_channel **channel;
> + struct iio_battery_platform_data *pdata;
> + struct delayed_work bat_work;
> + int was_plugged;
> + int volt_value;
> + int cur_value;
> + int level;
> + int status;
> + int cable_plugged:1;
> +};
> +
> +static void generic_adc_bat_ext_power_changed(struct power_supply *psy)
> +{
> + struct generic_adc_bat *adc_bat;
> + adc_bat = to_generic_bat(psy);
> +
> + schedule_delayed_work(&adc_bat->bat_work,
> + msecs_to_jiffies(adc_bat->pdata->jitter_delay));
> +}
> +
> +static enum power_supply_property bat_props[] = {
> + POWER_SUPPLY_PROP_STATUS,
> + POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
> + POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
> + POWER_SUPPLY_PROP_CHARGE_NOW,
> + POWER_SUPPLY_PROP_VOLTAGE_NOW,
> + POWER_SUPPLY_PROP_CURRENT_NOW,
> + POWER_SUPPLY_PROP_TECHNOLOGY,
> + POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
> + POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
> + POWER_SUPPLY_PROP_MODEL_NAME,
> +};
> +
> +/*
> + * This properties are set based on the received platform data and this
> + * should correspond one-to-one with enum chan_type.
> + */
> +static enum power_supply_property dyn_props[] = {
> + POWER_SUPPLY_PROP_VOLTAGE_NOW,
> + POWER_SUPPLY_PROP_CURRENT_NOW,
> + POWER_SUPPLY_PROP_POWER_NOW,
> +};
> +
> +static int charge_finished(struct generic_adc_bat *adc_bat)
> +{
> + return adc_bat->pdata->gpio_inverted ?
> + !gpio_get_value(adc_bat->pdata->gpio_charge_finished) :
> + gpio_get_value(adc_bat->pdata->gpio_charge_finished);
> +}
> +
> +long read_scale_channel(struct generic_adc_bat *adc_bat,
> + enum power_supply_property psp)
> +{
> + int scaleint, scalepart, iio_val, ret = 0;
> + int result = 0;
> +
> + switch (psp) {
> + case POWER_SUPPLY_PROP_POWER_NOW:
> + ret = iio_read_channel_raw(adc_bat->channel[POWER],
> + &iio_val);
> + ret = iio_read_channel_scale(adc_bat->channel[POWER],
> + &scaleint, &scalepart);
> + if (ret < 0)
> + return ret;
> + break;
> + case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> + ret = iio_read_channel_raw(adc_bat->channel[VOLTAGE],
> + &iio_val);
> + ret = iio_read_channel_scale(adc_bat->channel[VOLTAGE],
> + &scaleint, &scalepart);
> + if (ret < 0)
> + return ret;
> + break;
> + case POWER_SUPPLY_PROP_CURRENT_NOW:
> + ret = iio_read_channel_raw(adc_bat->channel[CURRENT],
> + &iio_val);
> + ret = iio_read_channel_scale(adc_bat->channel[CURRENT],
> + &scaleint, &scalepart);
> + if (ret < 0)
> + return ret;
> + break;
> + default:
> + break;
> + }
> +
> + switch (ret) {
> + case IIO_VAL_INT:
> + result = iio_val * scaleint;
> + break;
> + case IIO_VAL_INT_PLUS_MICRO:
> + result = (s64)iio_val * (s64)scaleint +
> + div_s64((s64)iio_val * (s64)scalepart, 1000000LL);
> + break;
> + case IIO_VAL_INT_PLUS_NANO:
> + result = (s64)iio_val * (s64)scaleint +
> + div_s64((s64)iio_val * (s64)scalepart, 1000000000LL);
> + break;
> + }
> + return result;
> +}
> +
> +static int generic_adc_bat_get_property(struct power_supply *psy,
> + enum power_supply_property psp,
> + union power_supply_propval *val)
> +{
> + struct generic_adc_bat *adc_bat;
> + int ret = 0;
> + long result;
> +
> + adc_bat = to_generic_bat(psy);
> + if (!adc_bat) {
> + dev_err(psy->dev, "no battery infos ?!\n");
> + return -EINVAL;
> + }
> +
> + result = read_scale_channel(adc_bat, psp);
> + if (result < 0) {
> + dev_err(psy->dev, "read channel error\n");
> + ret = -EINVAL;
> + goto err;
> + }
> +
> + switch (psp) {
> + case POWER_SUPPLY_PROP_STATUS:
> + if (gpio_is_valid(adc_bat->pdata->gpio_charge_finished)) {
> + if (adc_bat->pdata->gpio_charge_finished < 0)
> + val->intval = adc_bat->level == 100000 ?
> + POWER_SUPPLY_STATUS_FULL :
> + adc_bat->status;
> + else
> + val->intval = adc_bat->status;
> + }
> + break;
> + case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
> + val->intval = 0;
> + break;
> + case POWER_SUPPLY_PROP_CHARGE_NOW:
> + val->intval = adc_bat->pdata->cal_charge(result);
> + break;
> + case POWER_SUPPLY_PROP_VOLTAGE_NOW:
> + val->intval = result;
> + break;
> + case POWER_SUPPLY_PROP_CURRENT_NOW:
> + val->intval = result;
> + break;
> + case POWER_SUPPLY_PROP_POWER_NOW:
> + val->intval = result;
> + break;
> + case POWER_SUPPLY_PROP_TECHNOLOGY:
> + val->intval = adc_bat->pdata->battery_info.technology;
> + break;
> + case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
> + val->intval = adc_bat->pdata->battery_info.voltage_min_design;
> + break;
> + case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
> + val->intval = adc_bat->pdata->battery_info.voltage_max_design;
> + break;
> + case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
> + val->intval = adc_bat->pdata->battery_info.charge_full_design;
> + break;
> + case POWER_SUPPLY_PROP_MODEL_NAME:
> + val->strval = adc_bat->pdata->battery_info.name;
> + break;
> + default:
> + return -EINVAL;
> + }
> +err:
> + return ret;
> +}
> +
> +static void generic_adc_bat_work(struct work_struct *work)
> +{
> + struct generic_adc_bat *adc_bat;
> + struct delayed_work *delayed_work;
> + int is_charged;
> + int is_plugged;
> +
> + delayed_work = container_of(work,
> + struct delayed_work, work);
> + adc_bat = container_of(delayed_work,
> + struct generic_adc_bat, bat_work);
> +
> + is_plugged = power_supply_am_i_supplied(&adc_bat->psy);
> + adc_bat->cable_plugged = is_plugged;
> + if (is_plugged != adc_bat->was_plugged) {
> + adc_bat->was_plugged = is_plugged;
> + if (is_plugged)
> + adc_bat->status = POWER_SUPPLY_STATUS_CHARGING;
> + else
> + adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
> + } else {
> + if (gpio_is_valid(adc_bat->pdata->gpio_charge_finished)) {
> + if ((adc_bat->pdata->gpio_charge_finished >= 0) &&
> + is_plugged) {
> + is_charged = charge_finished(adc_bat);
> + if (is_charged)
> + adc_bat->status =
> + POWER_SUPPLY_STATUS_FULL;
> + else
> + adc_bat->status =
> + POWER_SUPPLY_STATUS_CHARGING;
> + }
> + }
> + }
> +
> + power_supply_changed(&adc_bat->psy);
> +}
> +
> +static irqreturn_t generic_adc_bat_charged(int irq, void *dev_id)
> +{
> + struct generic_adc_bat *adc_bat = dev_id;
> + adc_bat = container_of(&adc_bat->bat_work,
> + struct generic_adc_bat, bat_work);
> + schedule_delayed_work(&adc_bat->bat_work,
> + msecs_to_jiffies(adc_bat->pdata->jitter_delay));
> + return IRQ_HANDLED;
> +}
> +
> +static int __devinit generic_adc_bat_probe(struct platform_device *pdev)
> +{
> + struct generic_adc_bat *adc_bat;
> + struct iio_battery_platform_data *pdata = pdev->dev.platform_data;
> + int ret, chan_index, fail = 0;
> +
> + adc_bat = devm_kzalloc(&pdev->dev, sizeof(*adc_bat), GFP_KERNEL);
> + if (!adc_bat) {
> + dev_err(&pdev->dev, "failed to allocate memory\n");
> + return -ENOMEM;
> + }
> +
> + /* copying the battery name from platform data */
> + adc_bat->psy.name = pdata->battery_name;
> +
> + /* bootup default values for the battery */
> + adc_bat->volt_value = -1;
> + adc_bat->cur_value = -1;
> + adc_bat->cable_plugged = 0;
> + adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
> + adc_bat->psy.type = POWER_SUPPLY_TYPE_BATTERY;
> + adc_bat->psy.get_property =
> + generic_adc_bat_get_property;
> + adc_bat->psy.external_power_changed =
> + generic_adc_bat_ext_power_changed;
> +
> + adc_bat->pdata = pdata;
> +
> + /* calculate the total number of channels */
> + for (chan_index = 0; channel_name[chan_index]; chan_index++)
> + ;
> +
> + if (!chan_index) {
> + pr_err("atleast provide one channel\n");
> + return -EINVAL;
> + }
> +
> + /*
> + * copying the static properties and allocating extra memory for holding
> + * the extra configurable properties received from platform data.
> + */
> + adc_bat->psy.properties = kzalloc(sizeof(bat_props)
> + + sizeof(int)*chan_index, GFP_KERNEL);
> + if (!adc_bat->psy.properties) {
> + ret = -ENOMEM;
> + goto first_mem_fail;
> + }
> + memcpy(adc_bat->psy.properties, bat_props, sizeof(bat_props));
> +
> + /* allocating memory for iio channels */
> + adc_bat->channel = kzalloc(chan_index * sizeof(struct iio_channel),
> + GFP_KERNEL);
> + if (!adc_bat->channel) {
> + ret = -ENOMEM;
> + goto second_mem_fail;
> + }
> +
> + /*
> + * getting channel from iio and copying the battery properties
> + * based on the channel supported by consumer device.
> + */
> + for (chan_index = 0; channel_name[chan_index]; chan_index++) {
> + adc_bat->channel[chan_index] =
> + iio_channel_get(dev_name(&pdev->dev),
> + channel_name[chan_index]);
> + /* we skip for channels which fail */
> + if (IS_ERR(adc_bat->channel[chan_index]))
> + fail++;
> + else {
> + static int index;
> + memcpy(adc_bat->psy.properties +
> + sizeof(bat_props) + sizeof(int)*index,
> + &dyn_props[chan_index],
> + sizeof(dyn_props[chan_index]));
> + index++;
> + }
> + }
> +
> + /* none of the channels are supported so let's bail out */
> + if (fail == chan_index) {
> + ret = PTR_ERR(adc_bat->channel[chan_index]);
> + goto second_mem_fail;
> + }
> +
> + ret = power_supply_register(&pdev->dev, &adc_bat->psy);
> + if (ret)
> + goto err_reg_fail;
> +
> + INIT_DELAYED_WORK(&adc_bat->bat_work, generic_adc_bat_work);
> +
> + if (gpio_is_valid(pdata->gpio_charge_finished)) {
> + ret = gpio_request(pdata->gpio_charge_finished, "charged");
> + if (ret)
> + goto err_gpio;
> +
> + ret = request_any_context_irq(gpio_to_irq
> + (pdata->gpio_charge_finished),
> + generic_adc_bat_charged,
> + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
> + "battery charged", &adc_bat);
> + if (ret)
> + goto err_gpio;
> + } else
> + goto err_gpio; /* let's bail out */
> +
> + platform_set_drvdata(pdev, &adc_bat);
> +
> + /* Schedule timer to check current status */
> + schedule_delayed_work(&adc_bat->bat_work,
> + msecs_to_jiffies(0));
> + return 0;
> +
> +err_gpio:
> + power_supply_unregister(&adc_bat->psy);
> +err_reg_fail:
> + for (chan_index = 0; channel_name[chan_index]; chan_index++)
> + iio_channel_release(adc_bat->channel[chan_index]);
> + kfree(adc_bat->channel);
> +second_mem_fail:
> + kfree(adc_bat->psy.properties);
> +first_mem_fail:
> + return ret;
> +}
> +
> +static int generic_adc_bat_remove(struct platform_device *pdev)
> +{
> + int chan_index;
> + struct generic_adc_bat *adc_bat = platform_get_drvdata(pdev);
> +
> + power_supply_unregister(&adc_bat->psy);
> +
> + if (gpio_is_valid(adc_bat->pdata->gpio_charge_finished)) {
> + if (adc_bat->pdata->gpio_charge_finished >= 0) {
> + free_irq(gpio_to_irq(
> + adc_bat->pdata->gpio_charge_finished),
> + NULL);
> + gpio_free(adc_bat->pdata->gpio_charge_finished);
> + }
> + }
> +
> + for (chan_index = 0; channel_name[chan_index]; chan_index++)
> + iio_channel_release(adc_bat->channel[chan_index]);
> + cancel_delayed_work(&adc_bat->bat_work);
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int generic_adc_bat_suspend(struct device *dev)
> +{
> + struct generic_adc_bat *adc_bat = dev_get_drvdata(dev);
> +
> + cancel_delayed_work_sync(&adc_bat->bat_work);
> + adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
> + return 0;
> +}
> +
> +static int generic_adc_bat_resume(struct device *dev)
> +{
> + struct generic_adc_bat *adc_bat = dev_get_drvdata(dev);
> +
> + /* Schedule timer to check current status */
> + schedule_delayed_work(&adc_bat->bat_work,
> + msecs_to_jiffies(adc_bat->pdata->jitter_delay));
> + return 0;
> +}
> +
> +static const struct dev_pm_ops generic_adc_battery_pm_ops = {
> + .suspend = generic_adc_bat_suspend,
> + .resume = generic_adc_bat_resume,
> +};
> +
> +#define GENERIC_ADC_BATTERY_PM_OPS (&generic_adc_battery_pm_ops)
> +#else
> +#define GENERIC_ADC_BATTERY_PM_OPS (NULL)
> +#endif
> +
> +static struct platform_driver generic_adc_bat_driver = {
> + .driver = {
> + .name = "generic-adc-battery",
> + .owner = THIS_MODULE,
> + .pm = GENERIC_ADC_BATTERY_PM_OPS
> + },
> + .probe = generic_adc_bat_probe,
> + .remove = generic_adc_bat_remove,
> +};
> +
> +module_platform_driver(generic_adc_bat_driver);
> +
> +MODULE_AUTHOR("anish kumar <anish198519851985@gmail.com>");
> +MODULE_DESCRIPTION("generic battery driver using IIO");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/power/generic-adc-battery.h b/include/linux/power/generic-adc-battery.h
> new file mode 100644
> index 0000000..d7c6d20
> --- /dev/null
> +++ b/include/linux/power/generic-adc-battery.h
> @@ -0,0 +1,33 @@
> +/*
> + * 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.
> + */
> +
> +#ifndef GENERIC_ADC_BATTERY_H
> +#define GENERIC_ADC_BATTERY_H
> +
> +/* should be enough for the channel names */
> +#define BAT_MAX_NAME 30
> +
> +enum chan_type {
> + VOLTAGE = 0,
> + CURRENT,
> + POWER,
> + MAX_CHAN_TYPE
> +};
> +
why this definition?
> +extern char channel_name[][BAT_MAX_NAME + 1];
> +
> +struct iio_battery_platform_data {
> + struct power_supply_info battery_info;

Should this still be here?
> + char **channel_name;
> + char *battery_name;
> + int (*cal_charge)(long);
> + int gpio_charge_finished;
> + int gpio_inverted;

unused..
> + int bat_poll_interval;
> + int jitter_delay;
> +};
> +
> +#endif /* GENERIC_ADC_BATTERY_H */
>