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 timer_list charger_timer;
  37 static struct timer_list supply_timer;
  38 static struct timer_list polling_timer;
  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_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->state == OTG_STATE_B_PERIPHERAL);
 226 }
 227 #endif
 228
 229 static int pda_power_probe(struct platform_device *pdev)
 230 {
 231         int ret = 0;
 232
 233         dev = &pdev->dev;
 234
 235         if (pdev->id != -1) {
 236                 dev_err(dev, "it's meaningless to register several "
 237                         "pda_powers; use id = -1\n");
 238                 ret = -EINVAL;
 239                 goto wrongid;
 240         }
 241
 242         pdata = pdev->dev.platform_data;
 243
 244         if (pdata->init) {
 245                 ret = pdata->init(dev);
 246                 if (ret < 0)
 247                         goto init_failed;
 248         }
 249
 250         update_status();
 251         update_charger();
 252
 253         if (!pdata->wait_for_status)
 254                 pdata->wait_for_status = 500;
 255
 256         if (!pdata->wait_for_charger)
 257                 pdata->wait_for_charger = 500;
 258
 259         if (!pdata->polling_interval)
 260                 pdata->polling_interval = 2000;
 261
 262         if (!pdata->ac_max_uA)
 263                 pdata->ac_max_uA = 500000;
 264
 265         setup_timer(&charger_timer, charger_timer_func, 0);
 266         setup_timer(&supply_timer, supply_timer_func, 0);
 267
 268         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 269         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 270
 271         if (pdata->supplied_to) {
 272                 pda_psy_ac.supplied_to = pdata->supplied_to;
 273                 pda_psy_ac.num_supplicants = pdata->num_supplicants;
 274                 pda_psy_usb.supplied_to = pdata->supplied_to;
 275                 pda_psy_usb.num_supplicants = pdata->num_supplicants;
 276         }
 277
 278         ac_draw = regulator_get(dev, "ac_draw");
 279         if (IS_ERR(ac_draw)) {
 280                 dev_dbg(dev, "couldn't get ac_draw regulator\n");
 281                 ac_draw = NULL;
 282                 ret = PTR_ERR(ac_draw);
 283         }
 284
 285         if (pdata->is_ac_online) {
 286                 ret = power_supply_register(&pdev->dev, &pda_psy_ac);
 287                 if (ret) {
 288                         dev_err(dev, "failed to register %s power supply\n",
 289                                 pda_psy_ac.name);
 290                         goto ac_supply_failed;
 291                 }
 292
 293                 if (ac_irq) {
 294                         ret = request_irq(ac_irq->start, power_changed_isr,
 295                                           get_irq_flags(ac_irq), ac_irq->name,
 296                                           &pda_psy_ac);
 297                         if (ret) {
 298                                 dev_err(dev, "request ac irq failed\n");
 299                                 goto ac_irq_failed;
 300                         }
 301                 } else {
 302                         polling = 1;
 303                 }
 304         }
 305
 306 #ifdef CONFIG_USB_OTG_UTILS
 307         transceiver = otg_get_transceiver();
 308         if (transceiver && !pdata->is_usb_online) {
 309                 pdata->is_usb_online = otg_is_usb_online;
 310         }
 311 #endif
 312
 313         if (pdata->is_usb_online) {
 314                 ret = power_supply_register(&pdev->dev, &pda_psy_usb);
 315                 if (ret) {
 316                         dev_err(dev, "failed to register %s power supply\n",
 317                                 pda_psy_usb.name);
 318                         goto usb_supply_failed;
 319                 }
 320
 321                 if (usb_irq) {
 322                         ret = request_irq(usb_irq->start, power_changed_isr,
 323                                           get_irq_flags(usb_irq),
 324                                           usb_irq->name, &pda_psy_usb);
 325                         if (ret) {
 326                                 dev_err(dev, "request usb irq failed\n");
 327                                 goto usb_irq_failed;
 328                         }
 329                 } else {
 330                         polling = 1;
 331                 }
 332         }
 333
 334         if (polling) {
 335                 dev_dbg(dev, "will poll for status\n");
 336                 setup_timer(&polling_timer, polling_timer_func, 0);
 337                 mod_timer(&polling_timer,
 338                           jiffies + msecs_to_jiffies(pdata->polling_interval));
 339         }
 340
 341         if (ac_irq || usb_irq)
 342                 device_init_wakeup(&pdev->dev, 1);
 343
 344         return 0;
 345
 346 usb_irq_failed:
 347         if (pdata->is_usb_online)
 348                 power_supply_unregister(&pda_psy_usb);
 349 usb_supply_failed:
 350         if (pdata->is_ac_online && ac_irq)
 351                 free_irq(ac_irq->start, &pda_psy_ac);
 352 #ifdef CONFIG_USB_OTG_UTILS
 353         if (transceiver)
 354                 otg_put_transceiver(transceiver);
 355 #endif
 356 ac_irq_failed:
 357         if (pdata->is_ac_online)
 358                 power_supply_unregister(&pda_psy_ac);
 359 ac_supply_failed:
 360         if (ac_draw) {
 361                 regulator_put(ac_draw);
 362                 ac_draw = NULL;
 363         }
 364         if (pdata->exit)
 365                 pdata->exit(dev);
 366 init_failed:
 367 wrongid:
 368         return ret;
 369 }
 370
 371 static int pda_power_remove(struct platform_device *pdev)
 372 {
 373         if (pdata->is_usb_online && usb_irq)
 374                 free_irq(usb_irq->start, &pda_psy_usb);
 375         if (pdata->is_ac_online && ac_irq)
 376                 free_irq(ac_irq->start, &pda_psy_ac);
 377
 378         if (polling)
 379                 del_timer_sync(&polling_timer);
 380         del_timer_sync(&charger_timer);
 381         del_timer_sync(&supply_timer);
 382
 383         if (pdata->is_usb_online)
 384                 power_supply_unregister(&pda_psy_usb);
 385         if (pdata->is_ac_online)
 386                 power_supply_unregister(&pda_psy_ac);
 387 #ifdef CONFIG_USB_OTG_UTILS
 388         if (transceiver)
 389                 otg_put_transceiver(transceiver);
 390 #endif
 391         if (ac_draw) {
 392                 regulator_put(ac_draw);
 393                 ac_draw = NULL;
 394         }
 395         if (pdata->exit)
 396                 pdata->exit(dev);
 397
 398         return 0;
 399 }
 400
 401 #ifdef CONFIG_PM
 402 static int ac_wakeup_enabled;
 403 static int usb_wakeup_enabled;
 404
 405 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
 406 {
 407         if (device_may_wakeup(&pdev->dev)) {
 408                 if (ac_irq)
 409                         ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
 410                 if (usb_irq)
 411                         usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
 412         }
 413
 414         return 0;
 415 }
 416
 417 static int pda_power_resume(struct platform_device *pdev)
 418 {
 419         if (device_may_wakeup(&pdev->dev)) {
 420                 if (usb_irq && usb_wakeup_enabled)
 421                         disable_irq_wake(usb_irq->start);
 422                 if (ac_irq && ac_wakeup_enabled)
 423                         disable_irq_wake(ac_irq->start);
 424         }
 425
 426         return 0;
 427 }
 428 #else
 429 #define pda_power_suspend NULL
 430 #define pda_power_resume NULL
 431 #endif /* CONFIG_PM */
 432
 433 MODULE_ALIAS("platform:pda-power");
 434
 435 static struct platform_driver pda_power_pdrv = {
 436         .driver = {
 437                 .name = "pda-power",
 438         },
 439         .probe = pda_power_probe,
 440         .remove = pda_power_remove,
 441         .suspend = pda_power_suspend,
 442         .resume = pda_power_resume,
 443 };
 444
 445 static int __init pda_power_init(void)
 446 {
 447         return platform_driver_register(&pda_power_pdrv);
 448 }
 449
 450 static void __exit pda_power_exit(void)
 451 {
 452         platform_driver_unregister(&pda_power_pdrv);
 453 }
 454
 455 module_init(pda_power_init);
 456 module_exit(pda_power_exit);
 457 MODULE_LICENSE("GPL");
 458 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");