cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

twl4030_madc_battery.c (7624B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Dumb driver for LiIon batteries using TWL4030 madc.
      4 *
      5 * Copyright 2013 Golden Delicious Computers
      6 * Lukas Märdian <lukas@goldelico.com>
      7 *
      8 * Based on dumb driver for gta01 battery
      9 * Copyright 2009 Openmoko, Inc
     10 * Balaji Rao <balajirrao@openmoko.org>
     11 */
     12
     13#include <linux/module.h>
     14#include <linux/param.h>
     15#include <linux/delay.h>
     16#include <linux/workqueue.h>
     17#include <linux/platform_device.h>
     18#include <linux/power_supply.h>
     19#include <linux/slab.h>
     20#include <linux/sort.h>
     21#include <linux/power/twl4030_madc_battery.h>
     22#include <linux/iio/consumer.h>
     23
     24struct twl4030_madc_battery {
     25	struct power_supply *psy;
     26	struct twl4030_madc_bat_platform_data *pdata;
     27	struct iio_channel *channel_temp;
     28	struct iio_channel *channel_ichg;
     29	struct iio_channel *channel_vbat;
     30};
     31
     32static enum power_supply_property twl4030_madc_bat_props[] = {
     33	POWER_SUPPLY_PROP_PRESENT,
     34	POWER_SUPPLY_PROP_STATUS,
     35	POWER_SUPPLY_PROP_TECHNOLOGY,
     36	POWER_SUPPLY_PROP_VOLTAGE_NOW,
     37	POWER_SUPPLY_PROP_CURRENT_NOW,
     38	POWER_SUPPLY_PROP_CAPACITY,
     39	POWER_SUPPLY_PROP_CHARGE_FULL,
     40	POWER_SUPPLY_PROP_CHARGE_NOW,
     41	POWER_SUPPLY_PROP_TEMP,
     42	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
     43};
     44
     45static int madc_read(struct iio_channel *channel)
     46{
     47	int val, err;
     48	err = iio_read_channel_processed(channel, &val);
     49	if (err < 0)
     50		return err;
     51
     52	return val;
     53}
     54
     55static int twl4030_madc_bat_get_charging_status(struct twl4030_madc_battery *bt)
     56{
     57	return (madc_read(bt->channel_ichg) > 0) ? 1 : 0;
     58}
     59
     60static int twl4030_madc_bat_get_voltage(struct twl4030_madc_battery *bt)
     61{
     62	return madc_read(bt->channel_vbat);
     63}
     64
     65static int twl4030_madc_bat_get_current(struct twl4030_madc_battery *bt)
     66{
     67	return madc_read(bt->channel_ichg) * 1000;
     68}
     69
     70static int twl4030_madc_bat_get_temp(struct twl4030_madc_battery *bt)
     71{
     72	return madc_read(bt->channel_temp) * 10;
     73}
     74
     75static int twl4030_madc_bat_voltscale(struct twl4030_madc_battery *bat,
     76					int volt)
     77{
     78	struct twl4030_madc_bat_calibration *calibration;
     79	int i, res = 0;
     80
     81	/* choose charging curve */
     82	if (twl4030_madc_bat_get_charging_status(bat))
     83		calibration = bat->pdata->charging;
     84	else
     85		calibration = bat->pdata->discharging;
     86
     87	if (volt > calibration[0].voltage) {
     88		res = calibration[0].level;
     89	} else {
     90		for (i = 0; calibration[i+1].voltage >= 0; i++) {
     91			if (volt <= calibration[i].voltage &&
     92					volt >= calibration[i+1].voltage) {
     93				/* interval found - interpolate within range */
     94				res = calibration[i].level -
     95					((calibration[i].voltage - volt) *
     96					(calibration[i].level -
     97					calibration[i+1].level)) /
     98					(calibration[i].voltage -
     99					calibration[i+1].voltage);
    100				break;
    101			}
    102		}
    103	}
    104	return res;
    105}
    106
    107static int twl4030_madc_bat_get_property(struct power_supply *psy,
    108					enum power_supply_property psp,
    109					union power_supply_propval *val)
    110{
    111	struct twl4030_madc_battery *bat = power_supply_get_drvdata(psy);
    112
    113	switch (psp) {
    114	case POWER_SUPPLY_PROP_STATUS:
    115		if (twl4030_madc_bat_voltscale(bat,
    116				twl4030_madc_bat_get_voltage(bat)) > 95)
    117			val->intval = POWER_SUPPLY_STATUS_FULL;
    118		else {
    119			if (twl4030_madc_bat_get_charging_status(bat))
    120				val->intval = POWER_SUPPLY_STATUS_CHARGING;
    121			else
    122				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
    123		}
    124		break;
    125	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
    126		val->intval = twl4030_madc_bat_get_voltage(bat) * 1000;
    127		break;
    128	case POWER_SUPPLY_PROP_TECHNOLOGY:
    129		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
    130		break;
    131	case POWER_SUPPLY_PROP_CURRENT_NOW:
    132		val->intval = twl4030_madc_bat_get_current(bat);
    133		break;
    134	case POWER_SUPPLY_PROP_PRESENT:
    135		/* assume battery is always present */
    136		val->intval = 1;
    137		break;
    138	case POWER_SUPPLY_PROP_CHARGE_NOW: {
    139			int percent = twl4030_madc_bat_voltscale(bat,
    140					twl4030_madc_bat_get_voltage(bat));
    141			val->intval = (percent * bat->pdata->capacity) / 100;
    142			break;
    143		}
    144	case POWER_SUPPLY_PROP_CAPACITY:
    145		val->intval = twl4030_madc_bat_voltscale(bat,
    146					twl4030_madc_bat_get_voltage(bat));
    147		break;
    148	case POWER_SUPPLY_PROP_CHARGE_FULL:
    149		val->intval = bat->pdata->capacity;
    150		break;
    151	case POWER_SUPPLY_PROP_TEMP:
    152		val->intval = twl4030_madc_bat_get_temp(bat);
    153		break;
    154	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: {
    155			int percent = twl4030_madc_bat_voltscale(bat,
    156					twl4030_madc_bat_get_voltage(bat));
    157			/* in mAh */
    158			int chg = (percent * (bat->pdata->capacity/1000))/100;
    159
    160			/* assume discharge with 400 mA (ca. 1.5W) */
    161			val->intval = (3600l * chg) / 400;
    162			break;
    163		}
    164	default:
    165		return -EINVAL;
    166	}
    167
    168	return 0;
    169}
    170
    171static void twl4030_madc_bat_ext_changed(struct power_supply *psy)
    172{
    173	power_supply_changed(psy);
    174}
    175
    176static const struct power_supply_desc twl4030_madc_bat_desc = {
    177	.name			= "twl4030_battery",
    178	.type			= POWER_SUPPLY_TYPE_BATTERY,
    179	.properties		= twl4030_madc_bat_props,
    180	.num_properties		= ARRAY_SIZE(twl4030_madc_bat_props),
    181	.get_property		= twl4030_madc_bat_get_property,
    182	.external_power_changed	= twl4030_madc_bat_ext_changed,
    183
    184};
    185
    186static int twl4030_cmp(const void *a, const void *b)
    187{
    188	return ((struct twl4030_madc_bat_calibration *)b)->voltage -
    189		((struct twl4030_madc_bat_calibration *)a)->voltage;
    190}
    191
    192static int twl4030_madc_battery_probe(struct platform_device *pdev)
    193{
    194	struct twl4030_madc_battery *twl4030_madc_bat;
    195	struct twl4030_madc_bat_platform_data *pdata = pdev->dev.platform_data;
    196	struct power_supply_config psy_cfg = {};
    197	int ret = 0;
    198
    199	twl4030_madc_bat = devm_kzalloc(&pdev->dev, sizeof(*twl4030_madc_bat),
    200				GFP_KERNEL);
    201	if (!twl4030_madc_bat)
    202		return -ENOMEM;
    203
    204	twl4030_madc_bat->channel_temp = iio_channel_get(&pdev->dev, "temp");
    205	if (IS_ERR(twl4030_madc_bat->channel_temp)) {
    206		ret = PTR_ERR(twl4030_madc_bat->channel_temp);
    207		goto err;
    208	}
    209
    210	twl4030_madc_bat->channel_ichg = iio_channel_get(&pdev->dev, "ichg");
    211	if (IS_ERR(twl4030_madc_bat->channel_ichg)) {
    212		ret = PTR_ERR(twl4030_madc_bat->channel_ichg);
    213		goto err_temp;
    214	}
    215
    216	twl4030_madc_bat->channel_vbat = iio_channel_get(&pdev->dev, "vbat");
    217	if (IS_ERR(twl4030_madc_bat->channel_vbat)) {
    218		ret = PTR_ERR(twl4030_madc_bat->channel_vbat);
    219		goto err_ichg;
    220	}
    221
    222	/* sort charging and discharging calibration data */
    223	sort(pdata->charging, pdata->charging_size,
    224		sizeof(struct twl4030_madc_bat_calibration),
    225		twl4030_cmp, NULL);
    226	sort(pdata->discharging, pdata->discharging_size,
    227		sizeof(struct twl4030_madc_bat_calibration),
    228		twl4030_cmp, NULL);
    229
    230	twl4030_madc_bat->pdata = pdata;
    231	platform_set_drvdata(pdev, twl4030_madc_bat);
    232	psy_cfg.drv_data = twl4030_madc_bat;
    233	twl4030_madc_bat->psy = power_supply_register(&pdev->dev,
    234						      &twl4030_madc_bat_desc,
    235						      &psy_cfg);
    236	if (IS_ERR(twl4030_madc_bat->psy)) {
    237		ret = PTR_ERR(twl4030_madc_bat->psy);
    238		goto err_vbat;
    239	}
    240
    241	return 0;
    242
    243err_vbat:
    244	iio_channel_release(twl4030_madc_bat->channel_vbat);
    245err_ichg:
    246	iio_channel_release(twl4030_madc_bat->channel_ichg);
    247err_temp:
    248	iio_channel_release(twl4030_madc_bat->channel_temp);
    249err:
    250	return ret;
    251}
    252
    253static int twl4030_madc_battery_remove(struct platform_device *pdev)
    254{
    255	struct twl4030_madc_battery *bat = platform_get_drvdata(pdev);
    256
    257	power_supply_unregister(bat->psy);
    258
    259	iio_channel_release(bat->channel_vbat);
    260	iio_channel_release(bat->channel_ichg);
    261	iio_channel_release(bat->channel_temp);
    262
    263	return 0;
    264}
    265
    266static struct platform_driver twl4030_madc_battery_driver = {
    267	.driver = {
    268		.name = "twl4030_madc_battery",
    269	},
    270	.probe  = twl4030_madc_battery_probe,
    271	.remove = twl4030_madc_battery_remove,
    272};
    273module_platform_driver(twl4030_madc_battery_driver);
    274
    275MODULE_LICENSE("GPL");
    276MODULE_AUTHOR("Lukas Märdian <lukas@goldelico.com>");
    277MODULE_DESCRIPTION("twl4030_madc battery driver");
    278MODULE_ALIAS("platform:twl4030_madc_battery");