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/power_supply.h>
  18 #include <linux/pda_power.h>
  19 #include <linux/regulator/consumer.h>
  20 #include <linux/timer.h>
  21 #include <linux/jiffies.h>
  22 #include <linux/usb/otg.h>
  23
  24 static inline unsigned int get_irq_flags(struct resource *res)
  25 {
  26         unsigned int flags = IRQF_SAMPLE_RANDOM | IRQF_SHARED;
  27
  28         flags |= res->flags & IRQF_TRIGGER_MASK;
  29
  30         return flags;
  31 }
  32
  33 static struct device *dev;
  34 static struct pda_power_pdata *pdata;
  35 static struct resource *ac_irq, *usb_irq;
  36 static struct delayed_work charger_work;
  37 static struct delayed_work polling_work;
  38 static struct delayed_work supply_work;
  39 static int polling;
  40
  41 #ifdef CONFIG_USB_OTG_UTILS
  42 static struct otg_transceiver *transceiver;
  43 #endif
  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_work_func(struct work_struct *work)
 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         cancel_delayed_work(&supply_work);
 169         schedule_delayed_work(&supply_work,
 170                               msecs_to_jiffies(pdata->wait_for_charger));
 171 }
 172
 173 static void charger_work_func(struct work_struct *work)
 174 {
 175         update_status();
 176         psy_changed();
 177 }
 178
 179 static irqreturn_t power_changed_isr(int irq, void *power_supply)
 180 {
 181         if (power_supply == &pda_psy_ac)
 182                 ac_status = PDA_PSY_TO_CHANGE;
 183         else if (power_supply == &pda_psy_usb)
 184                 usb_status = PDA_PSY_TO_CHANGE;
 185         else
 186                 return IRQ_NONE;
 187
 188         /*
 189          * Wait a bit before reading ac/usb line status and setting charger,
 190          * because ac/usb status readings may lag from irq.
 191          */
 192         cancel_delayed_work(&charger_work);
 193         schedule_delayed_work(&charger_work,
 194                               msecs_to_jiffies(pdata->wait_for_status));
 195
 196         return IRQ_HANDLED;
 197 }
 198
 199 static void polling_work_func(struct work_struct *work)
 200 {
 201         int changed = 0;
 202
 203         dev_dbg(dev, "polling...\n");
 204
 205         update_status();
 206
 207         if (!ac_irq && new_ac_status != ac_status) {
 208                 ac_status = PDA_PSY_TO_CHANGE;
 209                 changed = 1;
 210         }
 211
 212         if (!usb_irq && new_usb_status != usb_status) {
 213                 usb_status = PDA_PSY_TO_CHANGE;
 214                 changed = 1;
 215         }
 216
 217         if (changed)
 218                 psy_changed();
 219
 220         cancel_delayed_work(&polling_work);
 221         schedule_delayed_work(&polling_work,
 222                               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->state == OTG_STATE_B_PERIPHERAL);
 229 }
 230 #endif
 231
 232 static int pda_power_probe(struct platform_device *pdev)
 233 {
 234         int ret = 0;
 235
 236         dev = &pdev->dev;
 237
 238         if (pdev->id != -1) {
 239                 dev_err(dev, "it's meaningless to register several "
 240                         "pda_powers; use id = -1\n");
 241                 ret = -EINVAL;
 242                 goto wrongid;
 243         }
 244
 245         pdata = pdev->dev.platform_data;
 246
 247         if (pdata->init) {
 248                 ret = pdata->init(dev);
 249                 if (ret < 0)
 250                         goto init_failed;
 251         }
 252
 253         update_status();
 254         update_charger();
 255
 256         if (!pdata->wait_for_status)
 257                 pdata->wait_for_status = 500;
 258
 259         if (!pdata->wait_for_charger)
 260                 pdata->wait_for_charger = 500;
 261
 262         if (!pdata->polling_interval)
 263                 pdata->polling_interval = 2000;
 264
 265         if (!pdata->ac_max_uA)
 266                 pdata->ac_max_uA = 500000;
 267
 268         INIT_DELAYED_WORK(&charger_work, charger_work_func);
 269         INIT_DELAYED_WORK(&supply_work, supply_work_func);
 270
 271         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 272         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 273
 274         if (pdata->supplied_to) {
 275                 pda_psy_ac.supplied_to = pdata->supplied_to;
 276                 pda_psy_ac.num_supplicants = pdata->num_supplicants;
 277                 pda_psy_usb.supplied_to = pdata->supplied_to;
 278                 pda_psy_usb.num_supplicants = pdata->num_supplicants;
 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                 ret = PTR_ERR(ac_draw);
 286         }
 287
 288         if (pdata->is_ac_online) {
 289                 ret = power_supply_register(&pdev->dev, &pda_psy_ac);
 290                 if (ret) {
 291                         dev_err(dev, "failed to register %s power supply\n",
 292                                 pda_psy_ac.name);
 293                         goto ac_supply_failed;
 294                 }
 295
 296                 if (ac_irq) {
 297                         ret = request_irq(ac_irq->start, power_changed_isr,
 298                                           get_irq_flags(ac_irq), ac_irq->name,
 299                                           &pda_psy_ac);
 300                         if (ret) {
 301                                 dev_err(dev, "request ac irq failed\n");
 302                                 goto ac_irq_failed;
 303                         }
 304                 } else {
 305                         polling = 1;
 306                 }
 307         }
 308
 309 #ifdef CONFIG_USB_OTG_UTILS
 310         transceiver = otg_get_transceiver();
 311         if (transceiver && !pdata->is_usb_online) {
 312                 pdata->is_usb_online = otg_is_usb_online;
 313         }
 314 #endif
 315
 316         if (pdata->is_usb_online) {
 317                 ret = power_supply_register(&pdev->dev, &pda_psy_usb);
 318                 if (ret) {
 319                         dev_err(dev, "failed to register %s power supply\n",
 320                                 pda_psy_usb.name);
 321                         goto usb_supply_failed;
 322                 }
 323
 324                 if (usb_irq) {
 325                         ret = request_irq(usb_irq->start, power_changed_isr,
 326                                           get_irq_flags(usb_irq),
 327                                           usb_irq->name, &pda_psy_usb);
 328                         if (ret) {
 329                                 dev_err(dev, "request usb irq failed\n");
 330                                 goto usb_irq_failed;
 331                         }
 332                 } else {
 333                         polling = 1;
 334                 }
 335         }
 336
 337         if (polling) {
 338                 dev_dbg(dev, "will poll for status\n");
 339                 INIT_DELAYED_WORK(&polling_work, polling_work_func);
 340                 cancel_delayed_work(&polling_work);
 341                 schedule_delayed_work(&polling_work,
 342                                       msecs_to_jiffies(pdata->polling_interval));
 343         }
 344
 345         if (ac_irq || usb_irq)
 346                 device_init_wakeup(&pdev->dev, 1);
 347
 348         return 0;
 349
 350 usb_irq_failed:
 351         if (pdata->is_usb_online)
 352                 power_supply_unregister(&pda_psy_usb);
 353 usb_supply_failed:
 354         if (pdata->is_ac_online && ac_irq)
 355                 free_irq(ac_irq->start, &pda_psy_ac);
 356 #ifdef CONFIG_USB_OTG_UTILS
 357         if (transceiver)
 358                 otg_put_transceiver(transceiver);
 359 #endif
 360 ac_irq_failed:
 361         if (pdata->is_ac_online)
 362                 power_supply_unregister(&pda_psy_ac);
 363 ac_supply_failed:
 364         if (ac_draw) {
 365                 regulator_put(ac_draw);
 366                 ac_draw = NULL;
 367         }
 368         if (pdata->exit)
 369                 pdata->exit(dev);
 370 init_failed:
 371 wrongid:
 372         return ret;
 373 }
 374
 375 static int pda_power_remove(struct platform_device *pdev)
 376 {
 377         if (pdata->is_usb_online && usb_irq)
 378                 free_irq(usb_irq->start, &pda_psy_usb);
 379         if (pdata->is_ac_online && ac_irq)
 380                 free_irq(ac_irq->start, &pda_psy_ac);
 381
 382         if (polling)
 383                 cancel_delayed_work_sync(&polling_work);
 384         cancel_delayed_work_sync(&charger_work);
 385         cancel_delayed_work_sync(&supply_work);
 386
 387         if (pdata->is_usb_online)
 388                 power_supply_unregister(&pda_psy_usb);
 389         if (pdata->is_ac_online)
 390                 power_supply_unregister(&pda_psy_ac);
 391 #ifdef CONFIG_USB_OTG_UTILS
 392         if (transceiver)
 393                 otg_put_transceiver(transceiver);
 394 #endif
 395         if (ac_draw) {
 396                 regulator_put(ac_draw);
 397                 ac_draw = NULL;
 398         }
 399         if (pdata->exit)
 400                 pdata->exit(dev);
 401
 402         return 0;
 403 }
 404
 405 #ifdef CONFIG_PM
 406 static int ac_wakeup_enabled;
 407 static int usb_wakeup_enabled;
 408
 409 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
 410 {
 411         if (pdata->suspend) {
 412                 int ret = pdata->suspend(state);
 413
 414                 if (ret)
 415                         return ret;
 416         }
 417
 418         if (device_may_wakeup(&pdev->dev)) {
 419                 if (ac_irq)
 420                         ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
 421                 if (usb_irq)
 422                         usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
 423         }
 424
 425         return 0;
 426 }
 427
 428 static int pda_power_resume(struct platform_device *pdev)
 429 {
 430         if (device_may_wakeup(&pdev->dev)) {
 431                 if (usb_irq && usb_wakeup_enabled)
 432                         disable_irq_wake(usb_irq->start);
 433                 if (ac_irq && ac_wakeup_enabled)
 434                         disable_irq_wake(ac_irq->start);
 435         }
 436
 437         if (pdata->resume)
 438                 return pdata->resume();
 439
 440         return 0;
 441 }
 442 #else
 443 #define pda_power_suspend NULL
 444 #define pda_power_resume NULL
 445 #endif /* CONFIG_PM */
 446
 447 MODULE_ALIAS("platform:pda-power");
 448
 449 static struct platform_driver pda_power_pdrv = {
 450         .driver = {
 451                 .name = "pda-power",
 452         },
 453         .probe = pda_power_probe,
 454         .remove = pda_power_remove,
 455         .suspend = pda_power_suspend,
 456         .resume = pda_power_resume,
 457 };
 458
 459 static int __init pda_power_init(void)
 460 {
 461         return platform_driver_register(&pda_power_pdrv);
 462 }
 463
 464 static void __exit pda_power_exit(void)
 465 {
 466         platform_driver_unregister(&pda_power_pdrv);
 467 }
 468
 469 module_init(pda_power_init);
 470 module_exit(pda_power_exit);
 471 MODULE_LICENSE("GPL");
 472 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");