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 static struct power_supply *pda_psy_ac, *pda_psy_usb;
  38
  39 #if IS_ENABLED(CONFIG_USB_PHY)
  40 static struct usb_phy *transceiver;
  41 static struct notifier_block otg_nb;
  42 #endif
  43
  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->desc->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 const struct power_supply_desc pda_psy_ac_desc = {
  85         .name = "ac",
  86         .type = POWER_SUPPLY_TYPE_MAINS,
  87         .properties = pda_power_props,
  88         .num_properties = ARRAY_SIZE(pda_power_props),
  89         .get_property = pda_power_get_property,
  90 };
  91
  92 static const struct power_supply_desc pda_psy_usb_desc = {
  93         .name = "usb",
  94         .type = POWER_SUPPLY_TYPE_USB,
  95         .properties = pda_power_props,
  96         .num_properties = ARRAY_SIZE(pda_power_props),
  97         .get_property = pda_power_get_property,
  98 };
  99
 100 static void update_status(void)
 101 {
 102         if (pdata->is_ac_online)
 103                 new_ac_status = !!pdata->is_ac_online();
 104
 105         if (pdata->is_usb_online)
 106                 new_usb_status = !!pdata->is_usb_online();
 107 }
 108
 109 static void update_charger(void)
 110 {
 111         static int regulator_enabled;
 112         int max_uA = pdata->ac_max_uA;
 113
 114         if (pdata->set_charge) {
 115                 if (new_ac_status > 0) {
 116                         dev_dbg(dev, "charger on (AC)\n");
 117                         pdata->set_charge(PDA_POWER_CHARGE_AC);
 118                 } else if (new_usb_status > 0) {
 119                         dev_dbg(dev, "charger on (USB)\n");
 120                         pdata->set_charge(PDA_POWER_CHARGE_USB);
 121                 } else {
 122                         dev_dbg(dev, "charger off\n");
 123                         pdata->set_charge(0);
 124                 }
 125         } else if (ac_draw) {
 126                 if (new_ac_status > 0) {
 127                         regulator_set_current_limit(ac_draw, max_uA, max_uA);
 128                         if (!regulator_enabled) {
 129                                 dev_dbg(dev, "charger on (AC)\n");
 130                                 WARN_ON(regulator_enable(ac_draw));
 131                                 regulator_enabled = 1;
 132                         }
 133                 } else {
 134                         if (regulator_enabled) {
 135                                 dev_dbg(dev, "charger off\n");
 136                                 WARN_ON(regulator_disable(ac_draw));
 137                                 regulator_enabled = 0;
 138                         }
 139                 }
 140         }
 141 }
 142
 143 static void supply_timer_func(unsigned long unused)
 144 {
 145         if (ac_status == PDA_PSY_TO_CHANGE) {
 146                 ac_status = new_ac_status;
 147                 power_supply_changed(pda_psy_ac);
 148         }
 149
 150         if (usb_status == PDA_PSY_TO_CHANGE) {
 151                 usb_status = new_usb_status;
 152                 power_supply_changed(pda_psy_usb);
 153         }
 154 }
 155
 156 static void psy_changed(void)
 157 {
 158         update_charger();
 159
 160         /*
 161          * Okay, charger set. Now wait a bit before notifying supplicants,
 162          * charge power should stabilize.
 163          */
 164         mod_timer(&supply_timer,
 165                   jiffies + msecs_to_jiffies(pdata->wait_for_charger));
 166 }
 167
 168 static void charger_timer_func(unsigned long unused)
 169 {
 170         update_status();
 171         psy_changed();
 172 }
 173
 174 static irqreturn_t power_changed_isr(int irq, void *power_supply)
 175 {
 176         if (power_supply == pda_psy_ac)
 177                 ac_status = PDA_PSY_TO_CHANGE;
 178         else if (power_supply == pda_psy_usb)
 179                 usb_status = PDA_PSY_TO_CHANGE;
 180         else
 181                 return IRQ_NONE;
 182
 183         /*
 184          * Wait a bit before reading ac/usb line status and setting charger,
 185          * because ac/usb status readings may lag from irq.
 186          */
 187         mod_timer(&charger_timer,
 188                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 189
 190         return IRQ_HANDLED;
 191 }
 192
 193 static void polling_timer_func(unsigned long unused)
 194 {
 195         int changed = 0;
 196
 197         dev_dbg(dev, "polling...\n");
 198
 199         update_status();
 200
 201         if (!ac_irq && new_ac_status != ac_status) {
 202                 ac_status = PDA_PSY_TO_CHANGE;
 203                 changed = 1;
 204         }
 205
 206         if (!usb_irq && new_usb_status != usb_status) {
 207                 usb_status = PDA_PSY_TO_CHANGE;
 208                 changed = 1;
 209         }
 210
 211         if (changed)
 212                 psy_changed();
 213
 214         mod_timer(&polling_timer,
 215                   jiffies + msecs_to_jiffies(pdata->polling_interval));
 216 }
 217
 218 #if IS_ENABLED(CONFIG_USB_PHY)
 219 static int otg_is_usb_online(void)
 220 {
 221         return (transceiver->last_event == USB_EVENT_VBUS ||
 222                 transceiver->last_event == USB_EVENT_ENUMERATED);
 223 }
 224
 225 static int otg_is_ac_online(void)
 226 {
 227         return (transceiver->last_event == USB_EVENT_CHARGER);
 228 }
 229
 230 static int otg_handle_notification(struct notifier_block *nb,
 231                 unsigned long event, void *unused)
 232 {
 233         switch (event) {
 234         case USB_EVENT_CHARGER:
 235                 ac_status = PDA_PSY_TO_CHANGE;
 236                 break;
 237         case USB_EVENT_VBUS:
 238         case USB_EVENT_ENUMERATED:
 239                 usb_status = PDA_PSY_TO_CHANGE;
 240                 break;
 241         case USB_EVENT_NONE:
 242                 ac_status = PDA_PSY_TO_CHANGE;
 243                 usb_status = PDA_PSY_TO_CHANGE;
 244                 break;
 245         default:
 246                 return NOTIFY_OK;
 247         }
 248
 249         /*
 250          * Wait a bit before reading ac/usb line status and setting charger,
 251          * because ac/usb status readings may lag from irq.
 252          */
 253         mod_timer(&charger_timer,
 254                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 255
 256         return NOTIFY_OK;
 257 }
 258 #endif
 259
 260 static int pda_power_probe(struct platform_device *pdev)
 261 {
 262         struct power_supply_config psy_cfg = {};
 263         int ret = 0;
 264
 265         dev = &pdev->dev;
 266
 267         if (pdev->id != -1) {
 268                 dev_err(dev, "it's meaningless to register several "
 269                         "pda_powers; use id = -1\n");
 270                 ret = -EINVAL;
 271                 goto wrongid;
 272         }
 273
 274         pdata = pdev->dev.platform_data;
 275
 276         if (pdata->init) {
 277                 ret = pdata->init(dev);
 278                 if (ret < 0)
 279                         goto init_failed;
 280         }
 281
 282         ac_draw = regulator_get(dev, "ac_draw");
 283         if (IS_ERR(ac_draw)) {
 284                 dev_dbg(dev, "couldn't get ac_draw regulator\n");
 285                 ac_draw = NULL;
 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                 psy_cfg.supplied_to = pdata->supplied_to;
 311                 psy_cfg.num_supplicants = pdata->num_supplicants;
 312         } else {
 313                 psy_cfg.supplied_to = pda_power_supplied_to;
 314                 psy_cfg.num_supplicants = ARRAY_SIZE(pda_power_supplied_to);
 315         }
 316
 317 #if IS_ENABLED(CONFIG_USB_PHY)
 318         transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
 319         if (!IS_ERR_OR_NULL(transceiver)) {
 320                 if (!pdata->is_usb_online)
 321                         pdata->is_usb_online = otg_is_usb_online;
 322                 if (!pdata->is_ac_online)
 323                         pdata->is_ac_online = otg_is_ac_online;
 324         }
 325 #endif
 326
 327         if (pdata->is_ac_online) {
 328                 pda_psy_ac = power_supply_register(&pdev->dev,
 329                                                    &pda_psy_ac_desc, &psy_cfg);
 330                 if (IS_ERR(pda_psy_ac)) {
 331                         dev_err(dev, "failed to register %s power supply\n",
 332                                 pda_psy_ac_desc.name);
 333                         ret = PTR_ERR(pda_psy_ac);
 334                         goto ac_supply_failed;
 335                 }
 336
 337                 if (ac_irq) {
 338                         ret = request_irq(ac_irq->start, power_changed_isr,
 339                                           get_irq_flags(ac_irq), ac_irq->name,
 340                                           pda_psy_ac);
 341                         if (ret) {
 342                                 dev_err(dev, "request ac irq failed\n");
 343                                 goto ac_irq_failed;
 344                         }
 345                 } else {
 346                         polling = 1;
 347                 }
 348         }
 349
 350         if (pdata->is_usb_online) {
 351                 pda_psy_usb = power_supply_register(&pdev->dev,
 352                                                     &pda_psy_usb_desc,
 353                                                     &psy_cfg);
 354                 if (IS_ERR(pda_psy_usb)) {
 355                         dev_err(dev, "failed to register %s power supply\n",
 356                                 pda_psy_usb_desc.name);
 357                         ret = PTR_ERR(pda_psy_usb);
 358                         goto usb_supply_failed;
 359                 }
 360
 361                 if (usb_irq) {
 362                         ret = request_irq(usb_irq->start, power_changed_isr,
 363                                           get_irq_flags(usb_irq),
 364                                           usb_irq->name, pda_psy_usb);
 365                         if (ret) {
 366                                 dev_err(dev, "request usb irq failed\n");
 367                                 goto usb_irq_failed;
 368                         }
 369                 } else {
 370                         polling = 1;
 371                 }
 372         }
 373
 374 #if IS_ENABLED(CONFIG_USB_PHY)
 375         if (!IS_ERR_OR_NULL(transceiver) && pdata->use_otg_notifier) {
 376                 otg_nb.notifier_call = otg_handle_notification;
 377                 ret = usb_register_notifier(transceiver, &otg_nb);
 378                 if (ret) {
 379                         dev_err(dev, "failure to register otg notifier\n");
 380                         goto otg_reg_notifier_failed;
 381                 }
 382                 polling = 0;
 383         }
 384 #endif
 385
 386         if (polling) {
 387                 dev_dbg(dev, "will poll for status\n");
 388                 setup_timer(&polling_timer, polling_timer_func, 0);
 389                 mod_timer(&polling_timer,
 390                           jiffies + msecs_to_jiffies(pdata->polling_interval));
 391         }
 392
 393         if (ac_irq || usb_irq)
 394                 device_init_wakeup(&pdev->dev, 1);
 395
 396         return 0;
 397
 398 #if IS_ENABLED(CONFIG_USB_PHY)
 399 otg_reg_notifier_failed:
 400         if (pdata->is_usb_online && usb_irq)
 401                 free_irq(usb_irq->start, pda_psy_usb);
 402 #endif
 403 usb_irq_failed:
 404         if (pdata->is_usb_online)
 405                 power_supply_unregister(pda_psy_usb);
 406 usb_supply_failed:
 407         if (pdata->is_ac_online && ac_irq)
 408                 free_irq(ac_irq->start, pda_psy_ac);
 409 #if IS_ENABLED(CONFIG_USB_PHY)
 410         if (!IS_ERR_OR_NULL(transceiver))
 411                 usb_put_phy(transceiver);
 412 #endif
 413 ac_irq_failed:
 414         if (pdata->is_ac_online)
 415                 power_supply_unregister(pda_psy_ac);
 416 ac_supply_failed:
 417         if (ac_draw) {
 418                 regulator_put(ac_draw);
 419                 ac_draw = NULL;
 420         }
 421         if (pdata->exit)
 422                 pdata->exit(dev);
 423 init_failed:
 424 wrongid:
 425         return ret;
 426 }
 427
 428 static int pda_power_remove(struct platform_device *pdev)
 429 {
 430         if (pdata->is_usb_online && usb_irq)
 431                 free_irq(usb_irq->start, pda_psy_usb);
 432         if (pdata->is_ac_online && ac_irq)
 433                 free_irq(ac_irq->start, pda_psy_ac);
 434
 435         if (polling)
 436                 del_timer_sync(&polling_timer);
 437         del_timer_sync(&charger_timer);
 438         del_timer_sync(&supply_timer);
 439
 440         if (pdata->is_usb_online)
 441                 power_supply_unregister(pda_psy_usb);
 442         if (pdata->is_ac_online)
 443                 power_supply_unregister(pda_psy_ac);
 444 #if IS_ENABLED(CONFIG_USB_PHY)
 445         if (!IS_ERR_OR_NULL(transceiver))
 446                 usb_put_phy(transceiver);
 447 #endif
 448         if (ac_draw) {
 449                 regulator_put(ac_draw);
 450                 ac_draw = NULL;
 451         }
 452         if (pdata->exit)
 453                 pdata->exit(dev);
 454
 455         return 0;
 456 }
 457
 458 #ifdef CONFIG_PM
 459 static int ac_wakeup_enabled;
 460 static int usb_wakeup_enabled;
 461
 462 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
 463 {
 464         if (pdata->suspend) {
 465                 int ret = pdata->suspend(state);
 466
 467                 if (ret)
 468                         return ret;
 469         }
 470
 471         if (device_may_wakeup(&pdev->dev)) {
 472                 if (ac_irq)
 473                         ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
 474                 if (usb_irq)
 475                         usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
 476         }
 477
 478         return 0;
 479 }
 480
 481 static int pda_power_resume(struct platform_device *pdev)
 482 {
 483         if (device_may_wakeup(&pdev->dev)) {
 484                 if (usb_irq && usb_wakeup_enabled)
 485                         disable_irq_wake(usb_irq->start);
 486                 if (ac_irq && ac_wakeup_enabled)
 487                         disable_irq_wake(ac_irq->start);
 488         }
 489
 490         if (pdata->resume)
 491                 return pdata->resume();
 492
 493         return 0;
 494 }
 495 #else
 496 #define pda_power_suspend NULL
 497 #define pda_power_resume NULL
 498 #endif /* CONFIG_PM */
 499
 500 static struct platform_driver pda_power_pdrv = {
 501         .driver = {
 502                 .name = "pda-power",
 503         },
 504         .probe = pda_power_probe,
 505         .remove = pda_power_remove,
 506         .suspend = pda_power_suspend,
 507         .resume = pda_power_resume,
 508 };
 509
 510 module_platform_driver(pda_power_pdrv);
 511
 512 MODULE_LICENSE("GPL");
 513 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");
 514 MODULE_ALIAS("platform:pda-power");