drivers/power/pda_power.c

   1 /*
   2  * Common power driver for PDAs and phones with one or two external
   3  * power supplies (AC/USB) connected to main and backup batteries,
   4  * and optional builtin charger.
   5  *
   6  * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/power_supply.h>
  17 #include <linux/pda_power.h>
  18 #include <linux/timer.h>
  19 #include <linux/jiffies.h>
  20
  21 static inline unsigned int get_irq_flags(struct resource *res)
  22 {
  23         unsigned int flags = IRQF_DISABLED | IRQF_SHARED;
  24
  25         flags |= res->flags & IRQF_TRIGGER_MASK;
  26
  27         return flags;
  28 }
  29
  30 static struct device *dev;
  31 static struct pda_power_pdata *pdata;
  32 static struct resource *ac_irq, *usb_irq;
  33 static struct timer_list charger_timer;
  34 static struct timer_list supply_timer;
  35
  36 enum {
  37         PDA_PSY_OFFLINE = 0,
  38         PDA_PSY_ONLINE = 1,
  39         PDA_PSY_TO_CHANGE,
  40 };
  41 static int new_ac_status = -1;
  42 static int new_usb_status = -1;
  43 static int ac_status = -1;
  44 static int usb_status = -1;
  45
  46 static int pda_power_get_property(struct power_supply *psy,
  47                                   enum power_supply_property psp,
  48                                   union power_supply_propval *val)
  49 {
  50         switch (psp) {
  51         case POWER_SUPPLY_PROP_ONLINE:
  52                 if (psy->type == POWER_SUPPLY_TYPE_MAINS)
  53                         val->intval = pdata->is_ac_online ?
  54                                       pdata->is_ac_online() : 0;
  55                 else
  56                         val->intval = pdata->is_usb_online ?
  57                                       pdata->is_usb_online() : 0;
  58                 break;
  59         default:
  60                 return -EINVAL;
  61         }
  62         return 0;
  63 }
  64
  65 static enum power_supply_property pda_power_props[] = {
  66         POWER_SUPPLY_PROP_ONLINE,
  67 };
  68
  69 static char *pda_power_supplied_to[] = {
  70         "main-battery",
  71         "backup-battery",
  72 };
  73
  74 static struct power_supply pda_psy_ac = {
  75         .name = "ac",
  76         .type = POWER_SUPPLY_TYPE_MAINS,
  77         .supplied_to = pda_power_supplied_to,
  78         .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  79         .properties = pda_power_props,
  80         .num_properties = ARRAY_SIZE(pda_power_props),
  81         .get_property = pda_power_get_property,
  82 };
  83
  84 static struct power_supply pda_psy_usb = {
  85         .name = "usb",
  86         .type = POWER_SUPPLY_TYPE_USB,
  87         .supplied_to = pda_power_supplied_to,
  88         .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  89         .properties = pda_power_props,
  90         .num_properties = ARRAY_SIZE(pda_power_props),
  91         .get_property = pda_power_get_property,
  92 };
  93
  94 static void update_status(void)
  95 {
  96         if (pdata->is_ac_online)
  97                 new_ac_status = !!pdata->is_ac_online();
  98
  99         if (pdata->is_usb_online)
 100                 new_usb_status = !!pdata->is_usb_online();
 101 }
 102
 103 static void update_charger(void)
 104 {
 105         if (!pdata->set_charge)
 106                 return;
 107
 108         if (new_ac_status > 0) {
 109                 dev_dbg(dev, "charger on (AC)\n");
 110                 pdata->set_charge(PDA_POWER_CHARGE_AC);
 111         } else if (new_usb_status > 0) {
 112                 dev_dbg(dev, "charger on (USB)\n");
 113                 pdata->set_charge(PDA_POWER_CHARGE_USB);
 114         } else {
 115                 dev_dbg(dev, "charger off\n");
 116                 pdata->set_charge(0);
 117         }
 118 }
 119
 120 static void supply_timer_func(unsigned long unused)
 121 {
 122         if (ac_status == PDA_PSY_TO_CHANGE) {
 123                 ac_status = new_ac_status;
 124                 power_supply_changed(&pda_psy_ac);
 125         }
 126
 127         if (usb_status == PDA_PSY_TO_CHANGE) {
 128                 usb_status = new_usb_status;
 129                 power_supply_changed(&pda_psy_usb);
 130         }
 131 }
 132
 133 static void psy_changed(void)
 134 {
 135         update_charger();
 136
 137         /*
 138          * Okay, charger set. Now wait a bit before notifying supplicants,
 139          * charge power should stabilize.
 140          */
 141         mod_timer(&supply_timer,
 142                   jiffies + msecs_to_jiffies(pdata->wait_for_charger));
 143 }
 144
 145 static void charger_timer_func(unsigned long unused)
 146 {
 147         update_status();
 148         psy_changed();
 149 }
 150
 151 static irqreturn_t power_changed_isr(int irq, void *power_supply)
 152 {
 153         if (power_supply == &pda_psy_ac)
 154                 ac_status = PDA_PSY_TO_CHANGE;
 155         else if (power_supply == &pda_psy_usb)
 156                 usb_status = PDA_PSY_TO_CHANGE;
 157         else
 158                 return IRQ_NONE;
 159
 160         /*
 161          * Wait a bit before reading ac/usb line status and setting charger,
 162          * because ac/usb status readings may lag from irq.
 163          */
 164         mod_timer(&charger_timer,
 165                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 166
 167         return IRQ_HANDLED;
 168 }
 169
 170 static int pda_power_probe(struct platform_device *pdev)
 171 {
 172         int ret = 0;
 173
 174         dev = &pdev->dev;
 175
 176         if (pdev->id != -1) {
 177                 dev_err(dev, "it's meaningless to register several "
 178                         "pda_powers; use id = -1\n");
 179                 ret = -EINVAL;
 180                 goto wrongid;
 181         }
 182
 183         pdata = pdev->dev.platform_data;
 184
 185         update_status();
 186         update_charger();
 187
 188         if (!pdata->wait_for_status)
 189                 pdata->wait_for_status = 500;
 190
 191         if (!pdata->wait_for_charger)
 192                 pdata->wait_for_charger = 500;
 193
 194         setup_timer(&charger_timer, charger_timer_func, 0);
 195         setup_timer(&supply_timer, supply_timer_func, 0);
 196
 197         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 198         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 199
 200         if (pdata->supplied_to) {
 201                 pda_psy_ac.supplied_to = pdata->supplied_to;
 202                 pda_psy_ac.num_supplicants = pdata->num_supplicants;
 203                 pda_psy_usb.supplied_to = pdata->supplied_to;
 204                 pda_psy_usb.num_supplicants = pdata->num_supplicants;
 205         }
 206
 207         if (pdata->is_ac_online) {
 208                 ret = power_supply_register(&pdev->dev, &pda_psy_ac);
 209                 if (ret) {
 210                         dev_err(dev, "failed to register %s power supply\n",
 211                                 pda_psy_ac.name);
 212                         goto ac_supply_failed;
 213                 }
 214
 215                 if (ac_irq) {
 216                         ret = request_irq(ac_irq->start, power_changed_isr,
 217                                           get_irq_flags(ac_irq), ac_irq->name,
 218                                           &pda_psy_ac);
 219                         if (ret) {
 220                                 dev_err(dev, "request ac irq failed\n");
 221                                 goto ac_irq_failed;
 222                         }
 223                 }
 224         }
 225
 226         if (pdata->is_usb_online) {
 227                 ret = power_supply_register(&pdev->dev, &pda_psy_usb);
 228                 if (ret) {
 229                         dev_err(dev, "failed to register %s power supply\n",
 230                                 pda_psy_usb.name);
 231                         goto usb_supply_failed;
 232                 }
 233
 234                 if (usb_irq) {
 235                         ret = request_irq(usb_irq->start, power_changed_isr,
 236                                           get_irq_flags(usb_irq),
 237                                           usb_irq->name, &pda_psy_usb);
 238                         if (ret) {
 239                                 dev_err(dev, "request usb irq failed\n");
 240                                 goto usb_irq_failed;
 241                         }
 242                 }
 243         }
 244
 245         device_init_wakeup(&pdev->dev, 1);
 246
 247         return 0;
 248
 249 usb_irq_failed:
 250         if (pdata->is_usb_online)
 251                 power_supply_unregister(&pda_psy_usb);
 252 usb_supply_failed:
 253         if (pdata->is_ac_online && ac_irq)
 254                 free_irq(ac_irq->start, &pda_psy_ac);
 255 ac_irq_failed:
 256         if (pdata->is_ac_online)
 257                 power_supply_unregister(&pda_psy_ac);
 258 ac_supply_failed:
 259 wrongid:
 260         return ret;
 261 }
 262
 263 static int pda_power_remove(struct platform_device *pdev)
 264 {
 265         if (pdata->is_usb_online && usb_irq)
 266                 free_irq(usb_irq->start, &pda_psy_usb);
 267         if (pdata->is_ac_online && ac_irq)
 268                 free_irq(ac_irq->start, &pda_psy_ac);
 269
 270         del_timer_sync(&charger_timer);
 271         del_timer_sync(&supply_timer);
 272
 273         if (pdata->is_usb_online)
 274                 power_supply_unregister(&pda_psy_usb);
 275         if (pdata->is_ac_online)
 276                 power_supply_unregister(&pda_psy_ac);
 277
 278         return 0;
 279 }
 280
 281 #ifdef CONFIG_PM
 282 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
 283 {
 284         if (device_may_wakeup(&pdev->dev)) {
 285                 if (ac_irq)
 286                         enable_irq_wake(ac_irq->start);
 287                 if (usb_irq)
 288                         enable_irq_wake(usb_irq->start);
 289         }
 290
 291         return 0;
 292 }
 293
 294 static int pda_power_resume(struct platform_device *pdev)
 295 {
 296         if (device_may_wakeup(&pdev->dev)) {
 297                 if (usb_irq)
 298                         disable_irq_wake(usb_irq->start);
 299                 if (ac_irq)
 300                         disable_irq_wake(ac_irq->start);
 301         }
 302
 303         return 0;
 304 }
 305 #else
 306 #define pda_power_suspend NULL
 307 #define pda_power_resume NULL
 308 #endif /* CONFIG_PM */
 309
 310 static struct platform_driver pda_power_pdrv = {
 311         .driver = {
 312                 .name = "pda-power",
 313         },
 314         .probe = pda_power_probe,
 315         .remove = pda_power_remove,
 316         .suspend = pda_power_suspend,
 317         .resume = pda_power_resume,
 318 };
 319
 320 static int __init pda_power_init(void)
 321 {
 322         return platform_driver_register(&pda_power_pdrv);
 323 }
 324
 325 static void __exit pda_power_exit(void)
 326 {
 327         platform_driver_unregister(&pda_power_pdrv);
 328 }
 329
 330 module_init(pda_power_init);
 331 module_exit(pda_power_exit);
 332 MODULE_LICENSE("GPL");
 333 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");