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         return IRQF_SHARED | (res->flags & IRQF_TRIGGER_MASK);
  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 static struct timer_list polling_timer;
  36 static int polling;
  37
  38 #if IS_ENABLED(CONFIG_USB_PHY)
  39 static struct usb_phy *transceiver;
  40 static struct notifier_block otg_nb;
  41 #endif
  42
  43 static struct regulator *ac_draw;
  44
  45 enum {
  46         PDA_PSY_OFFLINE = 0,
  47         PDA_PSY_ONLINE = 1,
  48         PDA_PSY_TO_CHANGE,
  49 };
  50 static int new_ac_status = -1;
  51 static int new_usb_status = -1;
  52 static int ac_status = -1;
  53 static int usb_status = -1;
  54
  55 static int pda_power_get_property(struct power_supply *psy,
  56                                   enum power_supply_property psp,
  57                                   union power_supply_propval *val)
  58 {
  59         switch (psp) {
  60         case POWER_SUPPLY_PROP_ONLINE:
  61                 if (psy->type == POWER_SUPPLY_TYPE_MAINS)
  62                         val->intval = pdata->is_ac_online ?
  63                                       pdata->is_ac_online() : 0;
  64                 else
  65                         val->intval = pdata->is_usb_online ?
  66                                       pdata->is_usb_online() : 0;
  67                 break;
  68         default:
  69                 return -EINVAL;
  70         }
  71         return 0;
  72 }
  73
  74 static enum power_supply_property pda_power_props[] = {
  75         POWER_SUPPLY_PROP_ONLINE,
  76 };
  77
  78 static char *pda_power_supplied_to[] = {
  79         "main-battery",
  80         "backup-battery",
  81 };
  82
  83 static struct power_supply pda_psy_ac = {
  84         .name = "ac",
  85         .type = POWER_SUPPLY_TYPE_MAINS,
  86         .supplied_to = pda_power_supplied_to,
  87         .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  88         .properties = pda_power_props,
  89         .num_properties = ARRAY_SIZE(pda_power_props),
  90         .get_property = pda_power_get_property,
  91 };
  92
  93 static struct power_supply pda_psy_usb = {
  94         .name = "usb",
  95         .type = POWER_SUPPLY_TYPE_USB,
  96         .supplied_to = pda_power_supplied_to,
  97         .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  98         .properties = pda_power_props,
  99         .num_properties = ARRAY_SIZE(pda_power_props),
 100         .get_property = pda_power_get_property,
 101 };
 102
 103 static void update_status(void)
 104 {
 105         if (pdata->is_ac_online)
 106                 new_ac_status = !!pdata->is_ac_online();
 107
 108         if (pdata->is_usb_online)
 109                 new_usb_status = !!pdata->is_usb_online();
 110 }
 111
 112 static void update_charger(void)
 113 {
 114         static int regulator_enabled;
 115         int max_uA = pdata->ac_max_uA;
 116
 117         if (pdata->set_charge) {
 118                 if (new_ac_status > 0) {
 119                         dev_dbg(dev, "charger on (AC)\n");
 120                         pdata->set_charge(PDA_POWER_CHARGE_AC);
 121                 } else if (new_usb_status > 0) {
 122                         dev_dbg(dev, "charger on (USB)\n");
 123                         pdata->set_charge(PDA_POWER_CHARGE_USB);
 124                 } else {
 125                         dev_dbg(dev, "charger off\n");
 126                         pdata->set_charge(0);
 127                 }
 128         } else if (ac_draw) {
 129                 if (new_ac_status > 0) {
 130                         regulator_set_current_limit(ac_draw, max_uA, max_uA);
 131                         if (!regulator_enabled) {
 132                                 dev_dbg(dev, "charger on (AC)\n");
 133                                 WARN_ON(regulator_enable(ac_draw));
 134                                 regulator_enabled = 1;
 135                         }
 136                 } else {
 137                         if (regulator_enabled) {
 138                                 dev_dbg(dev, "charger off\n");
 139                                 WARN_ON(regulator_disable(ac_draw));
 140                                 regulator_enabled = 0;
 141                         }
 142                 }
 143         }
 144 }
 145
 146 static void supply_timer_func(unsigned long unused)
 147 {
 148         if (ac_status == PDA_PSY_TO_CHANGE) {
 149                 ac_status = new_ac_status;
 150                 power_supply_changed(&pda_psy_ac);
 151         }
 152
 153         if (usb_status == PDA_PSY_TO_CHANGE) {
 154                 usb_status = new_usb_status;
 155                 power_supply_changed(&pda_psy_usb);
 156         }
 157 }
 158
 159 static void psy_changed(void)
 160 {
 161         update_charger();
 162
 163         /*
 164          * Okay, charger set. Now wait a bit before notifying supplicants,
 165          * charge power should stabilize.
 166          */
 167         mod_timer(&supply_timer,
 168                   jiffies + msecs_to_jiffies(pdata->wait_for_charger));
 169 }
 170
 171 static void charger_timer_func(unsigned long unused)
 172 {
 173         update_status();
 174         psy_changed();
 175 }
 176
 177 static irqreturn_t power_changed_isr(int irq, void *power_supply)
 178 {
 179         if (power_supply == &pda_psy_ac)
 180                 ac_status = PDA_PSY_TO_CHANGE;
 181         else if (power_supply == &pda_psy_usb)
 182                 usb_status = PDA_PSY_TO_CHANGE;
 183         else
 184                 return IRQ_NONE;
 185
 186         /*
 187          * Wait a bit before reading ac/usb line status and setting charger,
 188          * because ac/usb status readings may lag from irq.
 189          */
 190         mod_timer(&charger_timer,
 191                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 192
 193         return IRQ_HANDLED;
 194 }
 195
 196 static void polling_timer_func(unsigned long unused)
 197 {
 198         int changed = 0;
 199
 200         dev_dbg(dev, "polling...\n");
 201
 202         update_status();
 203
 204         if (!ac_irq && new_ac_status != ac_status) {
 205                 ac_status = PDA_PSY_TO_CHANGE;
 206                 changed = 1;
 207         }
 208
 209         if (!usb_irq && new_usb_status != usb_status) {
 210                 usb_status = PDA_PSY_TO_CHANGE;
 211                 changed = 1;
 212         }
 213
 214         if (changed)
 215                 psy_changed();
 216
 217         mod_timer(&polling_timer,
 218                   jiffies + msecs_to_jiffies(pdata->polling_interval));
 219 }
 220
 221 #if IS_ENABLED(CONFIG_USB_PHY)
 222 static int otg_is_usb_online(void)
 223 {
 224         return (transceiver->last_event == USB_EVENT_VBUS ||
 225                 transceiver->last_event == USB_EVENT_ENUMERATED);
 226 }
 227
 228 static int otg_is_ac_online(void)
 229 {
 230         return (transceiver->last_event == USB_EVENT_CHARGER);
 231 }
 232
 233 static int otg_handle_notification(struct notifier_block *nb,
 234                 unsigned long event, void *unused)
 235 {
 236         switch (event) {
 237         case USB_EVENT_CHARGER:
 238                 ac_status = PDA_PSY_TO_CHANGE;
 239                 break;
 240         case USB_EVENT_VBUS:
 241         case USB_EVENT_ENUMERATED:
 242                 usb_status = PDA_PSY_TO_CHANGE;
 243                 break;
 244         case USB_EVENT_NONE:
 245                 ac_status = PDA_PSY_TO_CHANGE;
 246                 usb_status = PDA_PSY_TO_CHANGE;
 247                 break;
 248         default:
 249                 return NOTIFY_OK;
 250         }
 251
 252         /*
 253          * Wait a bit before reading ac/usb line status and setting charger,
 254          * because ac/usb status readings may lag from irq.
 255          */
 256         mod_timer(&charger_timer,
 257                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 258
 259         return NOTIFY_OK;
 260 }
 261 #endif
 262
 263 static int pda_power_probe(struct platform_device *pdev)
 264 {
 265         int ret = 0;
 266
 267         dev = &pdev->dev;
 268
 269         if (pdev->id != -1) {
 270                 dev_err(dev, "it's meaningless to register several "
 271                         "pda_powers; use id = -1\n");
 272                 ret = -EINVAL;
 273                 goto wrongid;
 274         }
 275
 276         pdata = pdev->dev.platform_data;
 277
 278         if (pdata->init) {
 279                 ret = pdata->init(dev);
 280                 if (ret < 0)
 281                         goto init_failed;
 282         }
 283
 284         ac_draw = regulator_get(dev, "ac_draw");
 285         if (IS_ERR(ac_draw)) {
 286                 dev_dbg(dev, "couldn't get ac_draw regulator\n");
 287                 ac_draw = NULL;
 288         }
 289
 290         update_status();
 291         update_charger();
 292
 293         if (!pdata->wait_for_status)
 294                 pdata->wait_for_status = 500;
 295
 296         if (!pdata->wait_for_charger)
 297                 pdata->wait_for_charger = 500;
 298
 299         if (!pdata->polling_interval)
 300                 pdata->polling_interval = 2000;
 301
 302         if (!pdata->ac_max_uA)
 303                 pdata->ac_max_uA = 500000;
 304
 305         setup_timer(&charger_timer, charger_timer_func, 0);
 306         setup_timer(&supply_timer, supply_timer_func, 0);
 307
 308         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 309         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 310
 311         if (pdata->supplied_to) {
 312                 pda_psy_ac.supplied_to = pdata->supplied_to;
 313                 pda_psy_ac.num_supplicants = pdata->num_supplicants;
 314                 pda_psy_usb.supplied_to = pdata->supplied_to;
 315                 pda_psy_usb.num_supplicants = pdata->num_supplicants;
 316         }
 317
 318 #if IS_ENABLED(CONFIG_USB_PHY)
 319         transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
 320         if (!IS_ERR_OR_NULL(transceiver)) {
 321                 if (!pdata->is_usb_online)
 322                         pdata->is_usb_online = otg_is_usb_online;
 323                 if (!pdata->is_ac_online)
 324                         pdata->is_ac_online = otg_is_ac_online;
 325         }
 326 #endif
 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 IS_ENABLED(CONFIG_USB_PHY)
 371         if (!IS_ERR_OR_NULL(transceiver) && pdata->use_otg_notifier) {
 372                 otg_nb.notifier_call = otg_handle_notification;
 373                 ret = usb_register_notifier(transceiver, &otg_nb);
 374                 if (ret) {
 375                         dev_err(dev, "failure to register otg notifier\n");
 376                         goto otg_reg_notifier_failed;
 377                 }
 378                 polling = 0;
 379         }
 380 #endif
 381
 382         if (polling) {
 383                 dev_dbg(dev, "will poll for status\n");
 384                 setup_timer(&polling_timer, polling_timer_func, 0);
 385                 mod_timer(&polling_timer,
 386                           jiffies + msecs_to_jiffies(pdata->polling_interval));
 387         }
 388
 389         if (ac_irq || usb_irq)
 390                 device_init_wakeup(&pdev->dev, 1);
 391
 392         return 0;
 393
 394 #if IS_ENABLED(CONFIG_USB_PHY)
 395 otg_reg_notifier_failed:
 396         if (pdata->is_usb_online && usb_irq)
 397                 free_irq(usb_irq->start, &pda_psy_usb);
 398 #endif
 399 usb_irq_failed:
 400         if (pdata->is_usb_online)
 401                 power_supply_unregister(&pda_psy_usb);
 402 usb_supply_failed:
 403         if (pdata->is_ac_online && ac_irq)
 404                 free_irq(ac_irq->start, &pda_psy_ac);
 405 #if IS_ENABLED(CONFIG_USB_PHY)
 406         if (!IS_ERR_OR_NULL(transceiver))
 407                 usb_put_phy(transceiver);
 408 #endif
 409 ac_irq_failed:
 410         if (pdata->is_ac_online)
 411                 power_supply_unregister(&pda_psy_ac);
 412 ac_supply_failed:
 413         if (ac_draw) {
 414                 regulator_put(ac_draw);
 415                 ac_draw = NULL;
 416         }
 417         if (pdata->exit)
 418                 pdata->exit(dev);
 419 init_failed:
 420 wrongid:
 421         return ret;
 422 }
 423
 424 static int pda_power_remove(struct platform_device *pdev)
 425 {
 426         if (pdata->is_usb_online && usb_irq)
 427                 free_irq(usb_irq->start, &pda_psy_usb);
 428         if (pdata->is_ac_online && ac_irq)
 429                 free_irq(ac_irq->start, &pda_psy_ac);
 430
 431         if (polling)
 432                 del_timer_sync(&polling_timer);
 433         del_timer_sync(&charger_timer);
 434         del_timer_sync(&supply_timer);
 435
 436         if (pdata->is_usb_online)
 437                 power_supply_unregister(&pda_psy_usb);
 438         if (pdata->is_ac_online)
 439                 power_supply_unregister(&pda_psy_ac);
 440 #if IS_ENABLED(CONFIG_USB_PHY)
 441         if (!IS_ERR_OR_NULL(transceiver))
 442                 usb_put_phy(transceiver);
 443 #endif
 444         if (ac_draw) {
 445                 regulator_put(ac_draw);
 446                 ac_draw = NULL;
 447         }
 448         if (pdata->exit)
 449                 pdata->exit(dev);
 450
 451         return 0;
 452 }
 453
 454 #ifdef CONFIG_PM
 455 static int ac_wakeup_enabled;
 456 static int usb_wakeup_enabled;
 457
 458 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
 459 {
 460         if (pdata->suspend) {
 461                 int ret = pdata->suspend(state);
 462
 463                 if (ret)
 464                         return ret;
 465         }
 466
 467         if (device_may_wakeup(&pdev->dev)) {
 468                 if (ac_irq)
 469                         ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
 470                 if (usb_irq)
 471                         usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
 472         }
 473
 474         return 0;
 475 }
 476
 477 static int pda_power_resume(struct platform_device *pdev)
 478 {
 479         if (device_may_wakeup(&pdev->dev)) {
 480                 if (usb_irq && usb_wakeup_enabled)
 481                         disable_irq_wake(usb_irq->start);
 482                 if (ac_irq && ac_wakeup_enabled)
 483                         disable_irq_wake(ac_irq->start);
 484         }
 485
 486         if (pdata->resume)
 487                 return pdata->resume();
 488
 489         return 0;
 490 }
 491 #else
 492 #define pda_power_suspend NULL
 493 #define pda_power_resume NULL
 494 #endif /* CONFIG_PM */
 495
 496 static struct platform_driver pda_power_pdrv = {
 497         .driver = {
 498                 .name = "pda-power",
 499         },
 500         .probe = pda_power_probe,
 501         .remove = pda_power_remove,
 502         .suspend = pda_power_suspend,
 503         .resume = pda_power_resume,
 504 };
 505
 506 module_platform_driver(pda_power_pdrv);
 507
 508 MODULE_LICENSE("GPL");
 509 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");
 510 MODULE_ALIAS("platform:pda-power");