LXR linux/drivers/power/wm97xx

   1/*
   2 * linux/drivers/power/wm97xx_battery.c
   3 *
   4 * Battery measurement code for WM97xx
   5 *
   6 * based on tosa_battery.c
   7 *
   8 * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>
   9 *
  10 * This program is free software; you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License version 2 as
  12 * published by the Free Software Foundation.
  13 *
  14 */
  15
  16#include <linux/init.h>
  17#include <linux/kernel.h>
  18#include <linux/module.h>
  19#include <linux/platform_device.h>
  20#include <linux/power_supply.h>
  21#include <linux/wm97xx.h>
  22#include <linux/spinlock.h>
  23#include <linux/interrupt.h>
  24#include <linux/gpio.h>
  25#include <linux/irq.h>
  26
  27static DEFINE_MUTEX(bat_lock);
  28static struct work_struct bat_work;
  29struct mutex work_lock;
  30static int bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
  31static struct wm97xx_batt_info *gpdata;
  32static enum power_supply_property *prop;
  33
  34static unsigned long wm97xx_read_bat(struct power_supply *bat_ps)
  35{
  36        struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
  37        struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
  38
  39        return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev->parent),
  40                                        pdata->batt_aux) * pdata->batt_mult /
  41                                        pdata->batt_div;
  42}
  43
  44static unsigned long wm97xx_read_temp(struct power_supply *bat_ps)
  45{
  46        struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
  47        struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
  48
  49        return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev->parent),
  50                                        pdata->temp_aux) * pdata->temp_mult /
  51                                        pdata->temp_div;
  52}
  53
  54static int wm97xx_bat_get_property(struct power_supply *bat_ps,
  55                            enum power_supply_property psp,
  56                            union power_supply_propval *val)
  57{
  58        struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
  59        struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
  60
  61        switch (psp) {
  62        case POWER_SUPPLY_PROP_STATUS:
  63                val->intval = bat_status;
  64                break;
  65        case POWER_SUPPLY_PROP_TECHNOLOGY:
  66                val->intval = pdata->batt_tech;
  67                break;
  68        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  69                if (pdata->batt_aux >= 0)
  70                        val->intval = wm97xx_read_bat(bat_ps);
  71                else
  72                        return -EINVAL;
  73                break;
  74        case POWER_SUPPLY_PROP_TEMP:
  75                if (pdata->temp_aux >= 0)
  76                        val->intval = wm97xx_read_temp(bat_ps);
  77                else
  78                        return -EINVAL;
  79                break;
  80        case POWER_SUPPLY_PROP_VOLTAGE_MAX:
  81                if (pdata->max_voltage >= 0)
  82                        val->intval = pdata->max_voltage;
  83                else
  84                        return -EINVAL;
  85                break;
  86        case POWER_SUPPLY_PROP_VOLTAGE_MIN:
  87                if (pdata->min_voltage >= 0)
  88                        val->intval = pdata->min_voltage;
  89                else
  90                        return -EINVAL;
  91                break;
  92        case POWER_SUPPLY_PROP_PRESENT:
  93                val->intval = 1;
  94                break;
  95        default:
  96                return -EINVAL;
  97        }
  98        return 0;
  99}
 100
 101static void wm97xx_bat_external_power_changed(struct power_supply *bat_ps)
 102{
 103        schedule_work(&bat_work);
 104}
 105
 106static void wm97xx_bat_update(struct power_supply *bat_ps)
 107{
 108        int old_status = bat_status;
 109        struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
 110        struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
 111
 112        mutex_lock(&work_lock);
 113
 114        bat_status = (pdata->charge_gpio >= 0) ?
 115                        (gpio_get_value(pdata->charge_gpio) ?
 116                        POWER_SUPPLY_STATUS_DISCHARGING :
 117                        POWER_SUPPLY_STATUS_CHARGING) :
 118                        POWER_SUPPLY_STATUS_UNKNOWN;
 119
 120        if (old_status != bat_status) {
 121                pr_debug("%s: %i -> %i\n", bat_ps->name, old_status,
 122                                        bat_status);
 123                power_supply_changed(bat_ps);
 124        }
 125
 126        mutex_unlock(&work_lock);
 127}
 128
 129static struct power_supply bat_ps = {
 130        .type                   = POWER_SUPPLY_TYPE_BATTERY,
 131        .get_property           = wm97xx_bat_get_property,
 132        .external_power_changed = wm97xx_bat_external_power_changed,
 133        .use_for_apm            = 1,
 134};
 135
 136static void wm97xx_bat_work(struct work_struct *work)
 137{
 138        wm97xx_bat_update(&bat_ps);
 139}
 140
 141static irqreturn_t wm97xx_chrg_irq(int irq, void *data)
 142{
 143        schedule_work(&bat_work);
 144        return IRQ_HANDLED;
 145}
 146
 147#ifdef CONFIG_PM
 148static int wm97xx_bat_suspend(struct device *dev)
 149{
 150        flush_scheduled_work();
 151        return 0;
 152}
 153
 154static int wm97xx_bat_resume(struct device *dev)
 155{
 156        schedule_work(&bat_work);
 157        return 0;
 158}
 159
 160static struct dev_pm_ops wm97xx_bat_pm_ops = {
 161        .suspend        = wm97xx_bat_suspend,
 162        .resume         = wm97xx_bat_resume,
 163};
 164#endif
 165
 166static int __devinit wm97xx_bat_probe(struct platform_device *dev)
 167{
 168        int ret = 0;
 169        int props = 1;  /* POWER_SUPPLY_PROP_PRESENT */
 170        int i = 0;
 171        struct wm97xx_pdata *wmdata = dev->dev.platform_data;
 172        struct wm97xx_batt_pdata *pdata;
 173
 174        if (gpdata) {
 175                dev_err(&dev->dev, "Do not pass platform_data through "
 176                        "wm97xx_bat_set_pdata!\n");
 177                return -EINVAL;
 178        } else
 179                pdata = wmdata->batt_pdata;
 180
 181        if (dev->id != -1)
 182                return -EINVAL;
 183
 184        mutex_init(&work_lock);
 185
 186        if (!pdata) {
 187                dev_err(&dev->dev, "No platform_data supplied\n");
 188                return -EINVAL;
 189        }
 190
 191        if (gpio_is_valid(pdata->charge_gpio)) {
 192                ret = gpio_request(pdata->charge_gpio, "BATT CHRG");
 193                if (ret)
 194                        goto err;
 195                ret = gpio_direction_input(pdata->charge_gpio);
 196                if (ret)
 197                        goto err2;
 198                ret = request_irq(gpio_to_irq(pdata->charge_gpio),
 199                                wm97xx_chrg_irq, IRQF_DISABLED,
 200                                "AC Detect", 0);
 201                if (ret)
 202                        goto err2;
 203                props++;        /* POWER_SUPPLY_PROP_STATUS */
 204        }
 205
 206        if (pdata->batt_tech >= 0)
 207                props++;        /* POWER_SUPPLY_PROP_TECHNOLOGY */
 208        if (pdata->temp_aux >= 0)
 209                props++;        /* POWER_SUPPLY_PROP_TEMP */
 210        if (pdata->batt_aux >= 0)
 211                props++;        /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
 212        if (pdata->max_voltage >= 0)
 213                props++;        /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
 214        if (pdata->min_voltage >= 0)
 215                props++;        /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
 216
 217        prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
 218        if (!prop)
 219                goto err3;
 220
 221        prop[i++] = POWER_SUPPLY_PROP_PRESENT;
 222        if (pdata->charge_gpio >= 0)
 223                prop[i++] = POWER_SUPPLY_PROP_STATUS;
 224        if (pdata->batt_tech >= 0)
 225                prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
 226        if (pdata->temp_aux >= 0)
 227                prop[i++] = POWER_SUPPLY_PROP_TEMP;
 228        if (pdata->batt_aux >= 0)
 229                prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
 230        if (pdata->max_voltage >= 0)
 231                prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
 232        if (pdata->min_voltage >= 0)
 233                prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;
 234
 235        INIT_WORK(&bat_work, wm97xx_bat_work);
 236
 237        if (!pdata->batt_name) {
 238                dev_info(&dev->dev, "Please consider setting proper battery "
 239                                "name in platform definition file, falling "
 240                                "back to name \"wm97xx-batt\"\n");
 241                bat_ps.name = "wm97xx-batt";
 242        } else
 243                bat_ps.name = pdata->batt_name;
 244
 245        bat_ps.properties = prop;
 246        bat_ps.num_properties = props;
 247
 248        ret = power_supply_register(&dev->dev, &bat_ps);
 249        if (!ret)
 250                schedule_work(&bat_work);
 251        else
 252                goto err4;
 253
 254        return 0;
 255err4:
 256        kfree(prop);
 257err3:
 258        if (gpio_is_valid(pdata->charge_gpio))
 259                free_irq(gpio_to_irq(pdata->charge_gpio), dev);
 260err2:
 261        if (gpio_is_valid(pdata->charge_gpio))
 262                gpio_free(pdata->charge_gpio);
 263err:
 264        return ret;
 265}
 266
 267static int __devexit wm97xx_bat_remove(struct platform_device *dev)
 268{
 269        struct wm97xx_pdata *wmdata = dev->dev.platform_data;
 270        struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
 271
 272        if (pdata && gpio_is_valid(pdata->charge_gpio)) {
 273                free_irq(gpio_to_irq(pdata->charge_gpio), dev);
 274                gpio_free(pdata->charge_gpio);
 275        }
 276        flush_scheduled_work();
 277        power_supply_unregister(&bat_ps);
 278        kfree(prop);
 279        return 0;
 280}
 281
 282static struct platform_driver wm97xx_bat_driver = {
 283        .driver = {
 284                .name   = "wm97xx-battery",
 285                .owner  = THIS_MODULE,
 286#ifdef CONFIG_PM
 287                .pm     = &wm97xx_bat_pm_ops,
 288#endif
 289        },
 290        .probe          = wm97xx_bat_probe,
 291        .remove         = __devexit_p(wm97xx_bat_remove),
 292};
 293
 294static int __init wm97xx_bat_init(void)
 295{
 296        return platform_driver_register(&wm97xx_bat_driver);
 297}
 298
 299static void __exit wm97xx_bat_exit(void)
 300{
 301        platform_driver_unregister(&wm97xx_bat_driver);
 302}
 303
 304void wm97xx_bat_set_pdata(struct wm97xx_batt_info *data)
 305{
 306        gpdata = data;
 307}
 308EXPORT_SYMBOL_GPL(wm97xx_bat_set_pdata);
 309
 310module_init(wm97xx_bat_init);
 311module_exit(wm97xx_bat_exit);
 312
 313MODULE_LICENSE("GPL");
 314MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
 315MODULE_DESCRIPTION("WM97xx battery driver");
 316