SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/power/wm97xx_battery.c

   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
  26 static DEFINE_MUTEX(bat_lock);
  27 static struct work_struct bat_work;
  28 struct mutex work_lock;
  29 static int bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
  30 static struct wm97xx_batt_info *gpdata;
  31 static enum power_supply_property *prop;
  32
  33 static unsigned long wm97xx_read_bat(struct power_supply *bat_ps)
  34 {
  35         struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
  36         struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
  37
  38         return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
  39                                         pdata->batt_aux) * pdata->batt_mult /
  40                                         pdata->batt_div;
  41 }
  42
  43 static unsigned long wm97xx_read_temp(struct power_supply *bat_ps)
  44 {
  45         struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
  46         struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
  47
  48         return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
  49                                         pdata->temp_aux) * pdata->temp_mult /
  50                                         pdata->temp_div;
  51 }
  52
  53 static int wm97xx_bat_get_property(struct power_supply *bat_ps,
  54                             enum power_supply_property psp,
  55                             union power_supply_propval *val)
  56 {
  57         struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
  58         struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
  59
  60         switch (psp) {
  61         case POWER_SUPPLY_PROP_STATUS:
  62                 val->intval = bat_status;
  63                 break;
  64         case POWER_SUPPLY_PROP_TECHNOLOGY:
  65                 val->intval = pdata->batt_tech;
  66                 break;
  67         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  68                 if (pdata->batt_aux >= 0)
  69                         val->intval = wm97xx_read_bat(bat_ps);
  70                 else
  71                         return -EINVAL;
  72                 break;
  73         case POWER_SUPPLY_PROP_TEMP:
  74                 if (pdata->temp_aux >= 0)
  75                         val->intval = wm97xx_read_temp(bat_ps);
  76                 else
  77                         return -EINVAL;
  78                 break;
  79         case POWER_SUPPLY_PROP_VOLTAGE_MAX:
  80                 if (pdata->max_voltage >= 0)
  81                         val->intval = pdata->max_voltage;
  82                 else
  83                         return -EINVAL;
  84                 break;
  85         case POWER_SUPPLY_PROP_VOLTAGE_MIN:
  86                 if (pdata->min_voltage >= 0)
  87                         val->intval = pdata->min_voltage;
  88                 else
  89                         return -EINVAL;
  90                 break;
  91         case POWER_SUPPLY_PROP_PRESENT:
  92                 val->intval = 1;
  93                 break;
  94         default:
  95                 return -EINVAL;
  96         }
  97         return 0;
  98 }
  99
 100 static void wm97xx_bat_external_power_changed(struct power_supply *bat_ps)
 101 {
 102         schedule_work(&bat_work);
 103 }
 104
 105 static void wm97xx_bat_update(struct power_supply *bat_ps)
 106 {
 107         int old_status = bat_status;
 108         struct wm97xx_pdata *wmdata = bat_ps->dev->parent->platform_data;
 109         struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
 110
 111         mutex_lock(&work_lock);
 112
 113         bat_status = (pdata->charge_gpio >= 0) ?
 114                         (gpio_get_value(pdata->charge_gpio) ?
 115                         POWER_SUPPLY_STATUS_DISCHARGING :
 116                         POWER_SUPPLY_STATUS_CHARGING) :
 117                         POWER_SUPPLY_STATUS_UNKNOWN;
 118
 119         if (old_status != bat_status) {
 120                 pr_debug("%s: %i -> %i\n", bat_ps->name, old_status,
 121                                         bat_status);
 122                 power_supply_changed(bat_ps);
 123         }
 124
 125         mutex_unlock(&work_lock);
 126 }
 127
 128 static struct power_supply bat_ps = {
 129         .type                   = POWER_SUPPLY_TYPE_BATTERY,
 130         .get_property           = wm97xx_bat_get_property,
 131         .external_power_changed = wm97xx_bat_external_power_changed,
 132         .use_for_apm            = 1,
 133 };
 134
 135 static void wm97xx_bat_work(struct work_struct *work)
 136 {
 137         wm97xx_bat_update(&bat_ps);
 138 }
 139
 140 #ifdef CONFIG_PM
 141 static int wm97xx_bat_suspend(struct platform_device *dev, pm_message_t state)
 142 {
 143         flush_scheduled_work();
 144         return 0;
 145 }
 146
 147 static int wm97xx_bat_resume(struct platform_device *dev)
 148 {
 149         schedule_work(&bat_work);
 150         return 0;
 151 }
 152 #else
 153 #define wm97xx_bat_suspend NULL
 154 #define wm97xx_bat_resume NULL
 155 #endif
 156
 157 static int __devinit wm97xx_bat_probe(struct platform_device *dev)
 158 {
 159         int ret = 0;
 160         int props = 1;  /* POWER_SUPPLY_PROP_PRESENT */
 161         int i = 0;
 162         struct wm97xx_pdata *wmdata = dev->dev.platform_data;
 163         struct wm97xx_batt_pdata *pdata;
 164
 165         if (gpdata) {
 166                 dev_err(&dev->dev, "Do not pass platform_data through "
 167                         "wm97xx_bat_set_pdata!\n");
 168                 return -EINVAL;
 169         } else
 170                 pdata = wmdata->batt_pdata;
 171
 172         if (dev->id != -1)
 173                 return -EINVAL;
 174
 175         mutex_init(&work_lock);
 176
 177         if (!pdata) {
 178                 dev_err(&dev->dev, "No platform_data supplied\n");
 179                 return -EINVAL;
 180         }
 181
 182         if (pdata->charge_gpio >= 0 && gpio_is_valid(pdata->charge_gpio)) {
 183                 ret = gpio_request(pdata->charge_gpio, "BATT CHRG");
 184                 if (ret)
 185                         goto err;
 186                 ret = gpio_direction_input(pdata->charge_gpio);
 187                 if (ret)
 188                         goto err2;
 189                 props++;        /* POWER_SUPPLY_PROP_STATUS */
 190         }
 191
 192         if (pdata->batt_tech >= 0)
 193                 props++;        /* POWER_SUPPLY_PROP_TECHNOLOGY */
 194         if (pdata->temp_aux >= 0)
 195                 props++;        /* POWER_SUPPLY_PROP_TEMP */
 196         if (pdata->batt_aux >= 0)
 197                 props++;        /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
 198         if (pdata->max_voltage >= 0)
 199                 props++;        /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
 200         if (pdata->min_voltage >= 0)
 201                 props++;        /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
 202
 203         prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
 204         if (!prop)
 205                 goto err2;
 206
 207         prop[i++] = POWER_SUPPLY_PROP_PRESENT;
 208         if (pdata->charge_gpio >= 0)
 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_ps.name = "wm97xx-batt";
 228         } else
 229                 bat_ps.name = pdata->batt_name;
 230
 231         bat_ps.properties = prop;
 232         bat_ps.num_properties = props;
 233
 234         ret = power_supply_register(&dev->dev, &bat_ps);
 235         if (!ret)
 236                 schedule_work(&bat_work);
 237         else
 238                 goto err3;
 239
 240         return 0;
 241 err3:
 242         kfree(prop);
 243 err2:
 244         gpio_free(pdata->charge_gpio);
 245 err:
 246         return ret;
 247 }
 248
 249 static int __devexit wm97xx_bat_remove(struct platform_device *dev)
 250 {
 251         struct wm97xx_pdata *wmdata = dev->dev.platform_data;
 252         struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;
 253
 254         if (pdata && pdata->charge_gpio && pdata->charge_gpio >= 0)
 255                 gpio_free(pdata->charge_gpio);
 256         flush_scheduled_work();
 257         power_supply_unregister(&bat_ps);
 258         kfree(prop);
 259         return 0;
 260 }
 261
 262 static struct platform_driver wm97xx_bat_driver = {
 263         .driver = {
 264                 .name   = "wm97xx-battery",
 265                 .owner  = THIS_MODULE,
 266         },
 267         .probe          = wm97xx_bat_probe,
 268         .remove         = __devexit_p(wm97xx_bat_remove),
 269         .suspend        = wm97xx_bat_suspend,
 270         .resume         = wm97xx_bat_resume,
 271 };
 272
 273 static int __init wm97xx_bat_init(void)
 274 {
 275         return platform_driver_register(&wm97xx_bat_driver);
 276 }
 277
 278 static void __exit wm97xx_bat_exit(void)
 279 {
 280         platform_driver_unregister(&wm97xx_bat_driver);
 281 }
 282
 283 void wm97xx_bat_set_pdata(struct wm97xx_batt_info *data)
 284 {
 285         gpdata = data;
 286 }
 287 EXPORT_SYMBOL_GPL(wm97xx_bat_set_pdata);
 288
 289 module_init(wm97xx_bat_init);
 290 module_exit(wm97xx_bat_exit);
 291
 292 MODULE_LICENSE("GPL");
 293 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
 294 MODULE_DESCRIPTION("WM97xx battery driver");