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