275 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Battery measurement code for WM97xx4 *5 * based on tosa_battery.c6 *7 * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>8 */9 10#include <linux/init.h>11#include <linux/kernel.h>12#include <linux/module.h>13#include <linux/platform_device.h>14#include <linux/power_supply.h>15#include <linux/wm97xx.h>16#include <linux/spinlock.h>17#include <linux/interrupt.h>18#include <linux/gpio/consumer.h>19#include <linux/irq.h>20#include <linux/slab.h>21 22static struct work_struct bat_work;23static struct gpio_desc *charge_gpiod;24static DEFINE_MUTEX(work_lock);25static int bat_status = POWER_SUPPLY_STATUS_UNKNOWN;26static enum power_supply_property *prop;27 28static unsigned long wm97xx_read_bat(struct power_supply *bat_ps)29{30 struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps);31 32 return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent),33 pdata->batt_aux) * pdata->batt_mult /34 pdata->batt_div;35}36 37static unsigned long wm97xx_read_temp(struct power_supply *bat_ps)38{39 struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps);40 41 return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent),42 pdata->temp_aux) * pdata->temp_mult /43 pdata->temp_div;44}45 46static int wm97xx_bat_get_property(struct power_supply *bat_ps,47 enum power_supply_property psp,48 union power_supply_propval *val)49{50 struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps);51 52 switch (psp) {53 case POWER_SUPPLY_PROP_STATUS:54 val->intval = bat_status;55 break;56 case POWER_SUPPLY_PROP_TECHNOLOGY:57 val->intval = pdata->batt_tech;58 break;59 case POWER_SUPPLY_PROP_VOLTAGE_NOW:60 if (pdata->batt_aux >= 0)61 val->intval = wm97xx_read_bat(bat_ps);62 else63 return -EINVAL;64 break;65 case POWER_SUPPLY_PROP_TEMP:66 if (pdata->temp_aux >= 0)67 val->intval = wm97xx_read_temp(bat_ps);68 else69 return -EINVAL;70 break;71 case POWER_SUPPLY_PROP_VOLTAGE_MAX:72 if (pdata->max_voltage >= 0)73 val->intval = pdata->max_voltage;74 else75 return -EINVAL;76 break;77 case POWER_SUPPLY_PROP_VOLTAGE_MIN:78 if (pdata->min_voltage >= 0)79 val->intval = pdata->min_voltage;80 else81 return -EINVAL;82 break;83 case POWER_SUPPLY_PROP_PRESENT:84 val->intval = 1;85 break;86 default:87 return -EINVAL;88 }89 return 0;90}91 92static void wm97xx_bat_external_power_changed(struct power_supply *bat_ps)93{94 schedule_work(&bat_work);95}96 97static void wm97xx_bat_update(struct power_supply *bat_ps)98{99 int old_status = bat_status;100 101 mutex_lock(&work_lock);102 103 bat_status = (charge_gpiod) ?104 (gpiod_get_value(charge_gpiod) ?105 POWER_SUPPLY_STATUS_DISCHARGING :106 POWER_SUPPLY_STATUS_CHARGING) :107 POWER_SUPPLY_STATUS_UNKNOWN;108 109 if (old_status != bat_status) {110 pr_debug("%s: %i -> %i\n", bat_ps->desc->name, old_status,111 bat_status);112 power_supply_changed(bat_ps);113 }114 115 mutex_unlock(&work_lock);116}117 118static struct power_supply *bat_psy;119static struct power_supply_desc bat_psy_desc = {120 .type = POWER_SUPPLY_TYPE_BATTERY,121 .get_property = wm97xx_bat_get_property,122 .external_power_changed = wm97xx_bat_external_power_changed,123 .use_for_apm = 1,124};125 126static void wm97xx_bat_work(struct work_struct *work)127{128 wm97xx_bat_update(bat_psy);129}130 131static irqreturn_t wm97xx_chrg_irq(int irq, void *data)132{133 schedule_work(&bat_work);134 return IRQ_HANDLED;135}136 137#ifdef CONFIG_PM138static int wm97xx_bat_suspend(struct device *dev)139{140 flush_work(&bat_work);141 return 0;142}143 144static int wm97xx_bat_resume(struct device *dev)145{146 schedule_work(&bat_work);147 return 0;148}149 150static const struct dev_pm_ops wm97xx_bat_pm_ops = {151 .suspend = wm97xx_bat_suspend,152 .resume = wm97xx_bat_resume,153};154#endif155 156static int wm97xx_bat_probe(struct platform_device *dev)157{158 int ret = 0;159 int props = 1; /* POWER_SUPPLY_PROP_PRESENT */160 int i = 0;161 struct wm97xx_batt_pdata *pdata = dev->dev.platform_data;162 struct power_supply_config cfg = {};163 164 if (!pdata) {165 dev_err(&dev->dev, "No platform data supplied\n");166 return -EINVAL;167 }168 169 cfg.drv_data = pdata;170 171 if (dev->id != -1)172 return -EINVAL;173 174 charge_gpiod = devm_gpiod_get_optional(&dev->dev, NULL, GPIOD_IN);175 if (IS_ERR(charge_gpiod))176 return dev_err_probe(&dev->dev,177 PTR_ERR(charge_gpiod),178 "failed to get charge GPIO\n");179 if (charge_gpiod) {180 gpiod_set_consumer_name(charge_gpiod, "BATT CHRG");181 ret = request_irq(gpiod_to_irq(charge_gpiod),182 wm97xx_chrg_irq, 0,183 "AC Detect", dev);184 if (ret)185 return dev_err_probe(&dev->dev, ret,186 "failed to request GPIO irq\n");187 props++; /* POWER_SUPPLY_PROP_STATUS */188 }189 190 if (pdata->batt_tech >= 0)191 props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */192 if (pdata->temp_aux >= 0)193 props++; /* POWER_SUPPLY_PROP_TEMP */194 if (pdata->batt_aux >= 0)195 props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */196 if (pdata->max_voltage >= 0)197 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */198 if (pdata->min_voltage >= 0)199 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */200 201 prop = kcalloc(props, sizeof(*prop), GFP_KERNEL);202 if (!prop) {203 ret = -ENOMEM;204 goto err3;205 }206 207 prop[i++] = POWER_SUPPLY_PROP_PRESENT;208 if (charge_gpiod)209 prop[i++] = POWER_SUPPLY_PROP_STATUS;210 if (pdata->batt_tech >= 0)211 prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;212 if (pdata->temp_aux >= 0)213 prop[i++] = POWER_SUPPLY_PROP_TEMP;214 if (pdata->batt_aux >= 0)215 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;216 if (pdata->max_voltage >= 0)217 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;218 if (pdata->min_voltage >= 0)219 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;220 221 INIT_WORK(&bat_work, wm97xx_bat_work);222 223 if (!pdata->batt_name) {224 dev_info(&dev->dev, "Please consider setting proper battery "225 "name in platform definition file, falling "226 "back to name \"wm97xx-batt\"\n");227 bat_psy_desc.name = "wm97xx-batt";228 } else229 bat_psy_desc.name = pdata->batt_name;230 231 bat_psy_desc.properties = prop;232 bat_psy_desc.num_properties = props;233 234 bat_psy = power_supply_register(&dev->dev, &bat_psy_desc, &cfg);235 if (!IS_ERR(bat_psy)) {236 schedule_work(&bat_work);237 } else {238 ret = PTR_ERR(bat_psy);239 goto err4;240 }241 242 return 0;243err4:244 kfree(prop);245err3:246 if (charge_gpiod)247 free_irq(gpiod_to_irq(charge_gpiod), dev);248 return ret;249}250 251static void wm97xx_bat_remove(struct platform_device *dev)252{253 if (charge_gpiod)254 free_irq(gpiod_to_irq(charge_gpiod), dev);255 cancel_work_sync(&bat_work);256 power_supply_unregister(bat_psy);257 kfree(prop);258}259 260static struct platform_driver wm97xx_bat_driver = {261 .driver = {262 .name = "wm97xx-battery",263#ifdef CONFIG_PM264 .pm = &wm97xx_bat_pm_ops,265#endif266 },267 .probe = wm97xx_bat_probe,268 .remove_new = wm97xx_bat_remove,269};270 271module_platform_driver(wm97xx_bat_driver);272 273MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");274MODULE_DESCRIPTION("WM97xx battery driver");275