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/err.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/notifier.h>
  18 #include <linux/power_supply.h>
  19 #include <linux/pda_power.h>
  20 #include <linux/regulator/consumer.h>
  21 #include <linux/timer.h>
  22 #include <linux/jiffies.h>
  23 #include <linux/usb/otg.h>
  24
  25 static inline unsigned int get_irq_flags(struct resource *res)
  26 {
  27         unsigned int flags = IRQF_SAMPLE_RANDOM | IRQF_SHARED;
  28
  29         flags |= res->flags & IRQF_TRIGGER_MASK;
  30
  31         return flags;
  32 }
  33
  34 static struct device *dev;
  35 static struct pda_power_pdata *pdata;
  36 static struct resource *ac_irq, *usb_irq;
  37 static struct timer_list charger_timer;
  38 static struct timer_list supply_timer;
  39 static struct timer_list polling_timer;
  40 static int polling;
  41
  42 #ifdef CONFIG_USB_OTG_UTILS
  43 static struct otg_transceiver *transceiver;
  44 static struct notifier_block otg_nb;
  45 #endif
  46
  47 static struct regulator *ac_draw;
  48
  49 enum {
  50         PDA_PSY_OFFLINE = 0,
  51         PDA_PSY_ONLINE = 1,
  52         PDA_PSY_TO_CHANGE,
  53 };
  54 static int new_ac_status = -1;
  55 static int new_usb_status = -1;
  56 static int ac_status = -1;
  57 static int usb_status = -1;
  58
  59 static int pda_power_get_property(struct power_supply *psy,
  60                                   enum power_supply_property psp,
  61                                   union power_supply_propval *val)
  62 {
  63         switch (psp) {
  64         case POWER_SUPPLY_PROP_ONLINE:
  65                 if (psy->type == POWER_SUPPLY_TYPE_MAINS)
  66                         val->intval = pdata->is_ac_online ?
  67                                       pdata->is_ac_online() : 0;
  68                 else
  69                         val->intval = pdata->is_usb_online ?
  70                                       pdata->is_usb_online() : 0;
  71                 break;
  72         default:
  73                 return -EINVAL;
  74         }
  75         return 0;
  76 }
  77
  78 static enum power_supply_property pda_power_props[] = {
  79         POWER_SUPPLY_PROP_ONLINE,
  80 };
  81
  82 static char *pda_power_supplied_to[] = {
  83         "main-battery",
  84         "backup-battery",
  85 };
  86
  87 static struct power_supply pda_psy_ac = {
  88         .name = "ac",
  89         .type = POWER_SUPPLY_TYPE_MAINS,
  90         .supplied_to = pda_power_supplied_to,
  91         .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  92         .properties = pda_power_props,
  93         .num_properties = ARRAY_SIZE(pda_power_props),
  94         .get_property = pda_power_get_property,
  95 };
  96
  97 static struct power_supply pda_psy_usb = {
  98         .name = "usb",
  99         .type = POWER_SUPPLY_TYPE_USB,
 100         .supplied_to = pda_power_supplied_to,
 101         .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
 102         .properties = pda_power_props,
 103         .num_properties = ARRAY_SIZE(pda_power_props),
 104         .get_property = pda_power_get_property,
 105 };
 106
 107 static void update_status(void)
 108 {
 109         if (pdata->is_ac_online)
 110                 new_ac_status = !!pdata->is_ac_online();
 111
 112         if (pdata->is_usb_online)
 113                 new_usb_status = !!pdata->is_usb_online();
 114 }
 115
 116 static void update_charger(void)
 117 {
 118         static int regulator_enabled;
 119         int max_uA = pdata->ac_max_uA;
 120
 121         if (pdata->set_charge) {
 122                 if (new_ac_status > 0) {
 123                         dev_dbg(dev, "charger on (AC)\n");
 124                         pdata->set_charge(PDA_POWER_CHARGE_AC);
 125                 } else if (new_usb_status > 0) {
 126                         dev_dbg(dev, "charger on (USB)\n");
 127                         pdata->set_charge(PDA_POWER_CHARGE_USB);
 128                 } else {
 129                         dev_dbg(dev, "charger off\n");
 130                         pdata->set_charge(0);
 131                 }
 132         } else if (ac_draw) {
 133                 if (new_ac_status > 0) {
 134                         regulator_set_current_limit(ac_draw, max_uA, max_uA);
 135                         if (!regulator_enabled) {
 136                                 dev_dbg(dev, "charger on (AC)\n");
 137                                 regulator_enable(ac_draw);
 138                                 regulator_enabled = 1;
 139                         }
 140                 } else {
 141                         if (regulator_enabled) {
 142                                 dev_dbg(dev, "charger off\n");
 143                                 regulator_disable(ac_draw);
 144                                 regulator_enabled = 0;
 145                         }
 146                 }
 147         }
 148 }
 149
 150 static void supply_timer_func(unsigned long unused)
 151 {
 152         if (ac_status == PDA_PSY_TO_CHANGE) {
 153                 ac_status = new_ac_status;
 154                 power_supply_changed(&pda_psy_ac);
 155         }
 156
 157         if (usb_status == PDA_PSY_TO_CHANGE) {
 158                 usb_status = new_usb_status;
 159                 power_supply_changed(&pda_psy_usb);
 160         }
 161 }
 162
 163 static void psy_changed(void)
 164 {
 165         update_charger();
 166
 167         /*
 168          * Okay, charger set. Now wait a bit before notifying supplicants,
 169          * charge power should stabilize.
 170          */
 171         mod_timer(&supply_timer,
 172                   jiffies + msecs_to_jiffies(pdata->wait_for_charger));
 173 }
 174
 175 static void charger_timer_func(unsigned long unused)
 176 {
 177         update_status();
 178         psy_changed();
 179 }
 180
 181 static irqreturn_t power_changed_isr(int irq, void *power_supply)
 182 {
 183         if (power_supply == &pda_psy_ac)
 184                 ac_status = PDA_PSY_TO_CHANGE;
 185         else if (power_supply == &pda_psy_usb)
 186                 usb_status = PDA_PSY_TO_CHANGE;
 187         else
 188                 return IRQ_NONE;
 189
 190         /*
 191          * Wait a bit before reading ac/usb line status and setting charger,
 192          * because ac/usb status readings may lag from irq.
 193          */
 194         mod_timer(&charger_timer,
 195                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 196
 197         return IRQ_HANDLED;
 198 }
 199
 200 static void polling_timer_func(unsigned long unused)
 201 {
 202         int changed = 0;
 203
 204         dev_dbg(dev, "polling...\n");
 205
 206         update_status();
 207
 208         if (!ac_irq && new_ac_status != ac_status) {
 209                 ac_status = PDA_PSY_TO_CHANGE;
 210                 changed = 1;
 211         }
 212
 213         if (!usb_irq && new_usb_status != usb_status) {
 214                 usb_status = PDA_PSY_TO_CHANGE;
 215                 changed = 1;
 216         }
 217
 218         if (changed)
 219                 psy_changed();
 220
 221         mod_timer(&polling_timer,
 222                   jiffies + msecs_to_jiffies(pdata->polling_interval));
 223 }
 224
 225 #ifdef CONFIG_USB_OTG_UTILS
 226 static int otg_is_usb_online(void)
 227 {
 228         return (transceiver->last_event == USB_EVENT_VBUS ||
 229                 transceiver->last_event == USB_EVENT_ENUMERATED);
 230 }
 231
 232 static int otg_is_ac_online(void)
 233 {
 234         return (transceiver->last_event == USB_EVENT_CHARGER);
 235 }
 236
 237 static int otg_handle_notification(struct notifier_block *nb,
 238                 unsigned long event, void *unused)
 239 {
 240         switch (event) {
 241         case USB_EVENT_CHARGER:
 242                 ac_status = PDA_PSY_TO_CHANGE;
 243                 break;
 244         case USB_EVENT_VBUS:
 245         case USB_EVENT_ENUMERATED:
 246                 usb_status = PDA_PSY_TO_CHANGE;
 247                 break;
 248         case USB_EVENT_NONE:
 249                 ac_status = PDA_PSY_TO_CHANGE;
 250                 usb_status = PDA_PSY_TO_CHANGE;
 251                 break;
 252         default:
 253                 return NOTIFY_OK;
 254         }
 255
 256         /*
 257          * Wait a bit before reading ac/usb line status and setting charger,
 258          * because ac/usb status readings may lag from irq.
 259          */
 260         mod_timer(&charger_timer,
 261                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 262
 263         return NOTIFY_OK;
 264 }
 265 #endif
 266
 267 static int pda_power_probe(struct platform_device *pdev)
 268 {
 269         int ret = 0;
 270
 271         dev = &pdev->dev;
 272
 273         if (pdev->id != -1) {
 274                 dev_err(dev, "it's meaningless to register several "
 275                         "pda_powers; use id = -1\n");
 276                 ret = -EINVAL;
 277                 goto wrongid;
 278         }
 279
 280         pdata = pdev->dev.platform_data;
 281
 282         if (pdata->init) {
 283                 ret = pdata->init(dev);
 284                 if (ret < 0)
 285                         goto init_failed;
 286         }
 287
 288         update_status();
 289         update_charger();
 290
 291         if (!pdata->wait_for_status)
 292                 pdata->wait_for_status = 500;
 293
 294         if (!pdata->wait_for_charger)
 295                 pdata->wait_for_charger = 500;
 296
 297         if (!pdata->polling_interval)
 298                 pdata->polling_interval = 2000;
 299
 300         if (!pdata->ac_max_uA)
 301                 pdata->ac_max_uA = 500000;
 302
 303         setup_timer(&charger_timer, charger_timer_func, 0);
 304         setup_timer(&supply_timer, supply_timer_func, 0);
 305
 306         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 307         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 308
 309         if (pdata->supplied_to) {
 310                 pda_psy_ac.supplied_to = pdata->supplied_to;
 311                 pda_psy_ac.num_supplicants = pdata->num_supplicants;
 312                 pda_psy_usb.supplied_to = pdata->supplied_to;
 313                 pda_psy_usb.num_supplicants = pdata->num_supplicants;
 314         }
 315
 316         ac_draw = regulator_get(dev, "ac_draw");
 317         if (IS_ERR(ac_draw)) {
 318                 dev_dbg(dev, "couldn't get ac_draw regulator\n");
 319                 ac_draw = NULL;
 320                 ret = PTR_ERR(ac_draw);
 321         }
 322
 323 #ifdef CONFIG_USB_OTG_UTILS
 324         transceiver = otg_get_transceiver();
 325         if (transceiver && !pdata->is_usb_online) {
 326                 pdata->is_usb_online = otg_is_usb_online;
 327         }
 328         if (transceiver && !pdata->is_ac_online) {
 329                 pdata->is_ac_online = otg_is_ac_online;
 330         }
 331 #endif
 332
 333         if (pdata->is_ac_online) {
 334                 ret = power_supply_register(&pdev->dev, &pda_psy_ac);
 335                 if (ret) {
 336                         dev_err(dev, "failed to register %s power supply\n",
 337                                 pda_psy_ac.name);
 338                         goto ac_supply_failed;
 339                 }
 340
 341                 if (ac_irq) {
 342                         ret = request_irq(ac_irq->start, power_changed_isr,
 343                                           get_irq_flags(ac_irq), ac_irq->name,
 344                                           &pda_psy_ac);
 345                         if (ret) {
 346                                 dev_err(dev, "request ac irq failed\n");
 347                                 goto ac_irq_failed;
 348                         }
 349                 } else {
 350                         polling = 1;
 351                 }
 352         }
 353
 354         if (pdata->is_usb_online) {
 355                 ret = power_supply_register(&pdev->dev, &pda_psy_usb);
 356                 if (ret) {
 357                         dev_err(dev, "failed to register %s power supply\n",
 358                                 pda_psy_usb.name);
 359                         goto usb_supply_failed;
 360                 }
 361
 362                 if (usb_irq) {
 363                         ret = request_irq(usb_irq->start, power_changed_isr,
 364                                           get_irq_flags(usb_irq),
 365                                           usb_irq->name, &pda_psy_usb);
 366                         if (ret) {
 367                                 dev_err(dev, "request usb irq failed\n");
 368                                 goto usb_irq_failed;
 369                         }
 370                 } else {
 371                         polling = 1;
 372                 }
 373         }
 374
 375 #ifdef CONFIG_USB_OTG_UTILS
 376         if (transceiver && pdata->use_otg_notifier) {
 377                 otg_nb.notifier_call = otg_handle_notification;
 378                 ret = otg_register_notifier(transceiver, &otg_nb);
 379                 if (ret) {
 380                         dev_err(dev, "failure to register otg notifier\n");
 381                         goto otg_reg_notifier_failed;
 382                 }
 383                 polling = 0;
 384         }
 385 #endif
 386
 387         if (polling) {
 388                 dev_dbg(dev, "will poll for status\n");
 389                 setup_timer(&polling_timer, polling_timer_func, 0);
 390                 mod_timer(&polling_timer,
 391                           jiffies + msecs_to_jiffies(pdata->polling_interval));
 392         }
 393
 394         if (ac_irq || usb_irq)
 395                 device_init_wakeup(&pdev->dev, 1);
 396
 397         return 0;
 398
 399 #ifdef CONFIG_USB_OTG_UTILS
 400 otg_reg_notifier_failed:
 401         if (pdata->is_usb_online && usb_irq)
 402                 free_irq(usb_irq->start, &pda_psy_usb);
 403 #endif
 404 usb_irq_failed:
 405         if (pdata->is_usb_online)
 406                 power_supply_unregister(&pda_psy_usb);
 407 usb_supply_failed:
 408         if (pdata->is_ac_online && ac_irq)
 409                 free_irq(ac_irq->start, &pda_psy_ac);
 410 #ifdef CONFIG_USB_OTG_UTILS
 411         if (transceiver)
 412                 otg_put_transceiver(transceiver);
 413 #endif
 414 ac_irq_failed:
 415         if (pdata->is_ac_online)
 416                 power_supply_unregister(&pda_psy_ac);
 417 ac_supply_failed:
 418         if (ac_draw) {
 419                 regulator_put(ac_draw);
 420                 ac_draw = NULL;
 421         }
 422         if (pdata->exit)
 423                 pdata->exit(dev);
 424 init_failed:
 425 wrongid:
 426         return ret;
 427 }
 428
 429 static int pda_power_remove(struct platform_device *pdev)
 430 {
 431         if (pdata->is_usb_online && usb_irq)
 432                 free_irq(usb_irq->start, &pda_psy_usb);
 433         if (pdata->is_ac_online && ac_irq)
 434                 free_irq(ac_irq->start, &pda_psy_ac);
 435
 436         if (polling)
 437                 del_timer_sync(&polling_timer);
 438         del_timer_sync(&charger_timer);
 439         del_timer_sync(&supply_timer);
 440
 441         if (pdata->is_usb_online)
 442                 power_supply_unregister(&pda_psy_usb);
 443         if (pdata->is_ac_online)
 444                 power_supply_unregister(&pda_psy_ac);
 445 #ifdef CONFIG_USB_OTG_UTILS
 446         if (transceiver)
 447                 otg_put_transceiver(transceiver);
 448 #endif
 449         if (ac_draw) {
 450                 regulator_put(ac_draw);
 451                 ac_draw = NULL;
 452         }
 453         if (pdata->exit)
 454                 pdata->exit(dev);
 455
 456         return 0;
 457 }
 458
 459 #ifdef CONFIG_PM
 460 static int ac_wakeup_enabled;
 461 static int usb_wakeup_enabled;
 462
 463 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
 464 {
 465         if (pdata->suspend) {
 466                 int ret = pdata->suspend(state);
 467
 468                 if (ret)
 469                         return ret;
 470         }
 471
 472         if (device_may_wakeup(&pdev->dev)) {
 473                 if (ac_irq)
 474                         ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
 475                 if (usb_irq)
 476                         usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
 477         }
 478
 479         return 0;
 480 }
 481
 482 static int pda_power_resume(struct platform_device *pdev)
 483 {
 484         if (device_may_wakeup(&pdev->dev)) {
 485                 if (usb_irq && usb_wakeup_enabled)
 486                         disable_irq_wake(usb_irq->start);
 487                 if (ac_irq && ac_wakeup_enabled)
 488                         disable_irq_wake(ac_irq->start);
 489         }
 490
 491         if (pdata->resume)
 492                 return pdata->resume();
 493
 494         return 0;
 495 }
 496 #else
 497 #define pda_power_suspend NULL
 498 #define pda_power_resume NULL
 499 #endif /* CONFIG_PM */
 500
 501 MODULE_ALIAS("platform:pda-power");
 502
 503 static struct platform_driver pda_power_pdrv = {
 504         .driver = {
 505                 .name = "pda-power",
 506         },
 507         .probe = pda_power_probe,
 508         .remove = pda_power_remove,
 509         .suspend = pda_power_suspend,
 510         .resume = pda_power_resume,
 511 };
 512
 513 static int __init pda_power_init(void)
 514 {
 515         return platform_driver_register(&pda_power_pdrv);
 516 }
 517
 518 static void __exit pda_power_exit(void)
 519 {
 520         platform_driver_unregister(&pda_power_pdrv);
 521 }
 522
 523 module_init(pda_power_init);
 524 module_exit(pda_power_exit);
 525 MODULE_LICENSE("GPL");
 526 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");