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         .properties = pda_power_props,
  87         .num_properties = ARRAY_SIZE(pda_power_props),
  88         .get_property = pda_power_get_property,
  89 };
  90
  91 static struct power_supply pda_psy_usb = {
  92         .name = "usb",
  93         .type = POWER_SUPPLY_TYPE_USB,
  94         .properties = pda_power_props,
  95         .num_properties = ARRAY_SIZE(pda_power_props),
  96         .get_property = pda_power_get_property,
  97 };
  98
  99 static void update_status(void)
 100 {
 101         if (pdata->is_ac_online)
 102                 new_ac_status = !!pdata->is_ac_online();
 103
 104         if (pdata->is_usb_online)
 105                 new_usb_status = !!pdata->is_usb_online();
 106 }
 107
 108 static void update_charger(void)
 109 {
 110         static int regulator_enabled;
 111         int max_uA = pdata->ac_max_uA;
 112
 113         if (pdata->set_charge) {
 114                 if (new_ac_status > 0) {
 115                         dev_dbg(dev, "charger on (AC)\n");
 116                         pdata->set_charge(PDA_POWER_CHARGE_AC);
 117                 } else if (new_usb_status > 0) {
 118                         dev_dbg(dev, "charger on (USB)\n");
 119                         pdata->set_charge(PDA_POWER_CHARGE_USB);
 120                 } else {
 121                         dev_dbg(dev, "charger off\n");
 122                         pdata->set_charge(0);
 123                 }
 124         } else if (ac_draw) {
 125                 if (new_ac_status > 0) {
 126                         regulator_set_current_limit(ac_draw, max_uA, max_uA);
 127                         if (!regulator_enabled) {
 128                                 dev_dbg(dev, "charger on (AC)\n");
 129                                 WARN_ON(regulator_enable(ac_draw));
 130                                 regulator_enabled = 1;
 131                         }
 132                 } else {
 133                         if (regulator_enabled) {
 134                                 dev_dbg(dev, "charger off\n");
 135                                 WARN_ON(regulator_disable(ac_draw));
 136                                 regulator_enabled = 0;
 137                         }
 138                 }
 139         }
 140 }
 141
 142 static void supply_timer_func(unsigned long unused)
 143 {
 144         if (ac_status == PDA_PSY_TO_CHANGE) {
 145                 ac_status = new_ac_status;
 146                 power_supply_changed(&pda_psy_ac);
 147         }
 148
 149         if (usb_status == PDA_PSY_TO_CHANGE) {
 150                 usb_status = new_usb_status;
 151                 power_supply_changed(&pda_psy_usb);
 152         }
 153 }
 154
 155 static void psy_changed(void)
 156 {
 157         update_charger();
 158
 159         /*
 160          * Okay, charger set. Now wait a bit before notifying supplicants,
 161          * charge power should stabilize.
 162          */
 163         mod_timer(&supply_timer,
 164                   jiffies + msecs_to_jiffies(pdata->wait_for_charger));
 165 }
 166
 167 static void charger_timer_func(unsigned long unused)
 168 {
 169         update_status();
 170         psy_changed();
 171 }
 172
 173 static irqreturn_t power_changed_isr(int irq, void *power_supply)
 174 {
 175         if (power_supply == &pda_psy_ac)
 176                 ac_status = PDA_PSY_TO_CHANGE;
 177         else if (power_supply == &pda_psy_usb)
 178                 usb_status = PDA_PSY_TO_CHANGE;
 179         else
 180                 return IRQ_NONE;
 181
 182         /*
 183          * Wait a bit before reading ac/usb line status and setting charger,
 184          * because ac/usb status readings may lag from irq.
 185          */
 186         mod_timer(&charger_timer,
 187                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 188
 189         return IRQ_HANDLED;
 190 }
 191
 192 static void polling_timer_func(unsigned long unused)
 193 {
 194         int changed = 0;
 195
 196         dev_dbg(dev, "polling...\n");
 197
 198         update_status();
 199
 200         if (!ac_irq && new_ac_status != ac_status) {
 201                 ac_status = PDA_PSY_TO_CHANGE;
 202                 changed = 1;
 203         }
 204
 205         if (!usb_irq && new_usb_status != usb_status) {
 206                 usb_status = PDA_PSY_TO_CHANGE;
 207                 changed = 1;
 208         }
 209
 210         if (changed)
 211                 psy_changed();
 212
 213         mod_timer(&polling_timer,
 214                   jiffies + msecs_to_jiffies(pdata->polling_interval));
 215 }
 216
 217 #if IS_ENABLED(CONFIG_USB_PHY)
 218 static int otg_is_usb_online(void)
 219 {
 220         return (transceiver->last_event == USB_EVENT_VBUS ||
 221                 transceiver->last_event == USB_EVENT_ENUMERATED);
 222 }
 223
 224 static int otg_is_ac_online(void)
 225 {
 226         return (transceiver->last_event == USB_EVENT_CHARGER);
 227 }
 228
 229 static int otg_handle_notification(struct notifier_block *nb,
 230                 unsigned long event, void *unused)
 231 {
 232         switch (event) {
 233         case USB_EVENT_CHARGER:
 234                 ac_status = PDA_PSY_TO_CHANGE;
 235                 break;
 236         case USB_EVENT_VBUS:
 237         case USB_EVENT_ENUMERATED:
 238                 usb_status = PDA_PSY_TO_CHANGE;
 239                 break;
 240         case USB_EVENT_NONE:
 241                 ac_status = PDA_PSY_TO_CHANGE;
 242                 usb_status = PDA_PSY_TO_CHANGE;
 243                 break;
 244         default:
 245                 return NOTIFY_OK;
 246         }
 247
 248         /*
 249          * Wait a bit before reading ac/usb line status and setting charger,
 250          * because ac/usb status readings may lag from irq.
 251          */
 252         mod_timer(&charger_timer,
 253                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 254
 255         return NOTIFY_OK;
 256 }
 257 #endif
 258
 259 static int pda_power_probe(struct platform_device *pdev)
 260 {
 261         struct power_supply_config psy_cfg = {};
 262         int ret = 0;
 263
 264         dev = &pdev->dev;
 265
 266         if (pdev->id != -1) {
 267                 dev_err(dev, "it's meaningless to register several "
 268                         "pda_powers; use id = -1\n");
 269                 ret = -EINVAL;
 270                 goto wrongid;
 271         }
 272
 273         pdata = pdev->dev.platform_data;
 274
 275         if (pdata->init) {
 276                 ret = pdata->init(dev);
 277                 if (ret < 0)
 278                         goto init_failed;
 279         }
 280
 281         ac_draw = regulator_get(dev, "ac_draw");
 282         if (IS_ERR(ac_draw)) {
 283                 dev_dbg(dev, "couldn't get ac_draw regulator\n");
 284                 ac_draw = NULL;
 285         }
 286
 287         update_status();
 288         update_charger();
 289
 290         if (!pdata->wait_for_status)
 291                 pdata->wait_for_status = 500;
 292
 293         if (!pdata->wait_for_charger)
 294                 pdata->wait_for_charger = 500;
 295
 296         if (!pdata->polling_interval)
 297                 pdata->polling_interval = 2000;
 298
 299         if (!pdata->ac_max_uA)
 300                 pdata->ac_max_uA = 500000;
 301
 302         setup_timer(&charger_timer, charger_timer_func, 0);
 303         setup_timer(&supply_timer, supply_timer_func, 0);
 304
 305         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 306         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 307
 308         if (pdata->supplied_to) {
 309                 psy_cfg.supplied_to = pdata->supplied_to;
 310                 psy_cfg.num_supplicants = pdata->num_supplicants;
 311         } else {
 312                 psy_cfg.supplied_to = pda_power_supplied_to;
 313                 psy_cfg.num_supplicants = ARRAY_SIZE(pda_power_supplied_to);
 314         }
 315
 316 #if IS_ENABLED(CONFIG_USB_PHY)
 317         transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
 318         if (!IS_ERR_OR_NULL(transceiver)) {
 319                 if (!pdata->is_usb_online)
 320                         pdata->is_usb_online = otg_is_usb_online;
 321                 if (!pdata->is_ac_online)
 322                         pdata->is_ac_online = otg_is_ac_online;
 323         }
 324 #endif
 325
 326         if (pdata->is_ac_online) {
 327                 ret = power_supply_register(&pdev->dev, &pda_psy_ac, &psy_cfg);
 328                 if (ret) {
 329                         dev_err(dev, "failed to register %s power supply\n",
 330                                 pda_psy_ac.name);
 331                         goto ac_supply_failed;
 332                 }
 333
 334                 if (ac_irq) {
 335                         ret = request_irq(ac_irq->start, power_changed_isr,
 336                                           get_irq_flags(ac_irq), ac_irq->name,
 337                                           &pda_psy_ac);
 338                         if (ret) {
 339                                 dev_err(dev, "request ac irq failed\n");
 340                                 goto ac_irq_failed;
 341                         }
 342                 } else {
 343                         polling = 1;
 344                 }
 345         }
 346
 347         if (pdata->is_usb_online) {
 348                 ret = power_supply_register(&pdev->dev, &pda_psy_usb, &psy_cfg);
 349                 if (ret) {
 350                         dev_err(dev, "failed to register %s power supply\n",
 351                                 pda_psy_usb.name);
 352                         goto usb_supply_failed;
 353                 }
 354
 355                 if (usb_irq) {
 356                         ret = request_irq(usb_irq->start, power_changed_isr,
 357                                           get_irq_flags(usb_irq),
 358                                           usb_irq->name, &pda_psy_usb);
 359                         if (ret) {
 360                                 dev_err(dev, "request usb irq failed\n");
 361                                 goto usb_irq_failed;
 362                         }
 363                 } else {
 364                         polling = 1;
 365                 }
 366         }
 367
 368 #if IS_ENABLED(CONFIG_USB_PHY)
 369         if (!IS_ERR_OR_NULL(transceiver) && pdata->use_otg_notifier) {
 370                 otg_nb.notifier_call = otg_handle_notification;
 371                 ret = usb_register_notifier(transceiver, &otg_nb);
 372                 if (ret) {
 373                         dev_err(dev, "failure to register otg notifier\n");
 374                         goto otg_reg_notifier_failed;
 375                 }
 376                 polling = 0;
 377         }
 378 #endif
 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 #if IS_ENABLED(CONFIG_USB_PHY)
 393 otg_reg_notifier_failed:
 394         if (pdata->is_usb_online && usb_irq)
 395                 free_irq(usb_irq->start, &pda_psy_usb);
 396 #endif
 397 usb_irq_failed:
 398         if (pdata->is_usb_online)
 399                 power_supply_unregister(&pda_psy_usb);
 400 usb_supply_failed:
 401         if (pdata->is_ac_online && ac_irq)
 402                 free_irq(ac_irq->start, &pda_psy_ac);
 403 #if IS_ENABLED(CONFIG_USB_PHY)
 404         if (!IS_ERR_OR_NULL(transceiver))
 405                 usb_put_phy(transceiver);
 406 #endif
 407 ac_irq_failed:
 408         if (pdata->is_ac_online)
 409                 power_supply_unregister(&pda_psy_ac);
 410 ac_supply_failed:
 411         if (ac_draw) {
 412                 regulator_put(ac_draw);
 413                 ac_draw = NULL;
 414         }
 415         if (pdata->exit)
 416                 pdata->exit(dev);
 417 init_failed:
 418 wrongid:
 419         return ret;
 420 }
 421
 422 static int pda_power_remove(struct platform_device *pdev)
 423 {
 424         if (pdata->is_usb_online && usb_irq)
 425                 free_irq(usb_irq->start, &pda_psy_usb);
 426         if (pdata->is_ac_online && ac_irq)
 427                 free_irq(ac_irq->start, &pda_psy_ac);
 428
 429         if (polling)
 430                 del_timer_sync(&polling_timer);
 431         del_timer_sync(&charger_timer);
 432         del_timer_sync(&supply_timer);
 433
 434         if (pdata->is_usb_online)
 435                 power_supply_unregister(&pda_psy_usb);
 436         if (pdata->is_ac_online)
 437                 power_supply_unregister(&pda_psy_ac);
 438 #if IS_ENABLED(CONFIG_USB_PHY)
 439         if (!IS_ERR_OR_NULL(transceiver))
 440                 usb_put_phy(transceiver);
 441 #endif
 442         if (ac_draw) {
 443                 regulator_put(ac_draw);
 444                 ac_draw = NULL;
 445         }
 446         if (pdata->exit)
 447                 pdata->exit(dev);
 448
 449         return 0;
 450 }
 451
 452 #ifdef CONFIG_PM
 453 static int ac_wakeup_enabled;
 454 static int usb_wakeup_enabled;
 455
 456 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
 457 {
 458         if (pdata->suspend) {
 459                 int ret = pdata->suspend(state);
 460
 461                 if (ret)
 462                         return ret;
 463         }
 464
 465         if (device_may_wakeup(&pdev->dev)) {
 466                 if (ac_irq)
 467                         ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
 468                 if (usb_irq)
 469                         usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
 470         }
 471
 472         return 0;
 473 }
 474
 475 static int pda_power_resume(struct platform_device *pdev)
 476 {
 477         if (device_may_wakeup(&pdev->dev)) {
 478                 if (usb_irq && usb_wakeup_enabled)
 479                         disable_irq_wake(usb_irq->start);
 480                 if (ac_irq && ac_wakeup_enabled)
 481                         disable_irq_wake(ac_irq->start);
 482         }
 483
 484         if (pdata->resume)
 485                 return pdata->resume();
 486
 487         return 0;
 488 }
 489 #else
 490 #define pda_power_suspend NULL
 491 #define pda_power_resume NULL
 492 #endif /* CONFIG_PM */
 493
 494 static struct platform_driver pda_power_pdrv = {
 495         .driver = {
 496                 .name = "pda-power",
 497         },
 498         .probe = pda_power_probe,
 499         .remove = pda_power_remove,
 500         .suspend = pda_power_suspend,
 501         .resume = pda_power_resume,
 502 };
 503
 504 module_platform_driver(pda_power_pdrv);
 505
 506 MODULE_LICENSE("GPL");
 507 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");
 508 MODULE_ALIAS("platform:pda-power");