power/supply/wm8350_power.c

   1 /*
   2  * Battery driver for wm8350 PMIC
   3  *
   4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
   5  *
   6  * Based on OLPC Battery Driver
   7  *
   8  * Copyright 2006  David Woodhouse <dwmw2@infradead.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/err.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/power_supply.h>
  19 #include <linux/mfd/wm8350/supply.h>
  20 #include <linux/mfd/wm8350/core.h>
  21 #include <linux/mfd/wm8350/comparator.h>
  22
  23 static int wm8350_read_battery_uvolts(struct wm8350 *wm8350)
  24 {
  25         return wm8350_read_auxadc(wm8350, WM8350_AUXADC_BATT, 0, 0)
  26                 * WM8350_AUX_COEFF;
  27 }
  28
  29 static int wm8350_read_line_uvolts(struct wm8350 *wm8350)
  30 {
  31         return wm8350_read_auxadc(wm8350, WM8350_AUXADC_LINE, 0, 0)
  32                 * WM8350_AUX_COEFF;
  33 }
  34
  35 static int wm8350_read_usb_uvolts(struct wm8350 *wm8350)
  36 {
  37         return wm8350_read_auxadc(wm8350, WM8350_AUXADC_USB, 0, 0)
  38                 * WM8350_AUX_COEFF;
  39 }
  40
  41 #define WM8350_BATT_SUPPLY      1
  42 #define WM8350_USB_SUPPLY       2
  43 #define WM8350_LINE_SUPPLY      4
  44
  45 static inline int wm8350_charge_time_min(struct wm8350 *wm8350, int min)
  46 {
  47         if (!wm8350->power.rev_g_coeff)
  48                 return (((min - 30) / 15) & 0xf) << 8;
  49         else
  50                 return (((min - 30) / 30) & 0xf) << 8;
  51 }
  52
  53 static int wm8350_get_supplies(struct wm8350 *wm8350)
  54 {
  55         u16 sm, ov, co, chrg;
  56         int supplies = 0;
  57
  58         sm = wm8350_reg_read(wm8350, WM8350_STATE_MACHINE_STATUS);
  59         ov = wm8350_reg_read(wm8350, WM8350_MISC_OVERRIDES);
  60         co = wm8350_reg_read(wm8350, WM8350_COMPARATOR_OVERRIDES);
  61         chrg = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2);
  62
  63         /* USB_SM */
  64         sm = (sm & WM8350_USB_SM_MASK) >> WM8350_USB_SM_SHIFT;
  65
  66         /* CHG_ISEL */
  67         chrg &= WM8350_CHG_ISEL_MASK;
  68
  69         /* If the USB state machine is active then we're using that with or
  70          * without battery, otherwise check for wall supply */
  71         if (((sm == WM8350_USB_SM_100_SLV) ||
  72              (sm == WM8350_USB_SM_500_SLV) ||
  73              (sm == WM8350_USB_SM_STDBY_SLV))
  74             && !(ov & WM8350_USB_LIMIT_OVRDE))
  75                 supplies = WM8350_USB_SUPPLY;
  76         else if (((sm == WM8350_USB_SM_100_SLV) ||
  77                   (sm == WM8350_USB_SM_500_SLV) ||
  78                   (sm == WM8350_USB_SM_STDBY_SLV))
  79                  && (ov & WM8350_USB_LIMIT_OVRDE) && (chrg == 0))
  80                 supplies = WM8350_USB_SUPPLY | WM8350_BATT_SUPPLY;
  81         else if (co & WM8350_WALL_FB_OVRDE)
  82                 supplies = WM8350_LINE_SUPPLY;
  83         else
  84                 supplies = WM8350_BATT_SUPPLY;
  85
  86         return supplies;
  87 }
  88
  89 static int wm8350_charger_config(struct wm8350 *wm8350,
  90                                  struct wm8350_charger_policy *policy)
  91 {
  92         u16 reg, eoc_mA, fast_limit_mA;
  93
  94         if (!policy) {
  95                 dev_warn(wm8350->dev,
  96                          "No charger policy, charger not configured.\n");
  97                 return -EINVAL;
  98         }
  99
 100         /* make sure USB fast charge current is not > 500mA */
 101         if (policy->fast_limit_USB_mA > 500) {
 102                 dev_err(wm8350->dev, "USB fast charge > 500mA\n");
 103                 return -EINVAL;
 104         }
 105
 106         eoc_mA = WM8350_CHG_EOC_mA(policy->eoc_mA);
 107
 108         wm8350_reg_unlock(wm8350);
 109
 110         reg = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1)
 111                 & WM8350_CHG_ENA_R168;
 112         wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1,
 113                          reg | eoc_mA | policy->trickle_start_mV |
 114                          WM8350_CHG_TRICKLE_TEMP_CHOKE |
 115                          WM8350_CHG_TRICKLE_USB_CHOKE |
 116                          WM8350_CHG_FAST_USB_THROTTLE);
 117
 118         if (wm8350_get_supplies(wm8350) & WM8350_USB_SUPPLY) {
 119                 fast_limit_mA =
 120                         WM8350_CHG_FAST_LIMIT_mA(policy->fast_limit_USB_mA);
 121                 wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2,
 122                             policy->charge_mV | policy->trickle_charge_USB_mA |
 123                             fast_limit_mA | wm8350_charge_time_min(wm8350,
 124                                                 policy->charge_timeout));
 125
 126         } else {
 127                 fast_limit_mA =
 128                         WM8350_CHG_FAST_LIMIT_mA(policy->fast_limit_mA);
 129                 wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2,
 130                             policy->charge_mV | policy->trickle_charge_mA |
 131                             fast_limit_mA | wm8350_charge_time_min(wm8350,
 132                                                 policy->charge_timeout));
 133         }
 134
 135         wm8350_reg_lock(wm8350);
 136         return 0;
 137 }
 138
 139 static int wm8350_batt_status(struct wm8350 *wm8350)
 140 {
 141         u16 state;
 142
 143         state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2);
 144         state &= WM8350_CHG_STS_MASK;
 145
 146         switch (state) {
 147         case WM8350_CHG_STS_OFF:
 148                 return POWER_SUPPLY_STATUS_DISCHARGING;
 149
 150         case WM8350_CHG_STS_TRICKLE:
 151         case WM8350_CHG_STS_FAST:
 152                 return POWER_SUPPLY_STATUS_CHARGING;
 153
 154         default:
 155                 return POWER_SUPPLY_STATUS_UNKNOWN;
 156         }
 157 }
 158
 159 static ssize_t charger_state_show(struct device *dev,
 160                                  struct device_attribute *attr, char *buf)
 161 {
 162         struct wm8350 *wm8350 = dev_get_drvdata(dev);
 163         char *charge;
 164         int state;
 165
 166         state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2) &
 167             WM8350_CHG_STS_MASK;
 168         switch (state) {
 169         case WM8350_CHG_STS_OFF:
 170                 charge = "Charger Off";
 171                 break;
 172         case WM8350_CHG_STS_TRICKLE:
 173                 charge = "Trickle Charging";
 174                 break;
 175         case WM8350_CHG_STS_FAST:
 176                 charge = "Fast Charging";
 177                 break;
 178         default:
 179                 return 0;
 180         }
 181
 182         return sprintf(buf, "%s\n", charge);
 183 }
 184
 185 static DEVICE_ATTR_RO(charger_state);
 186
 187 static irqreturn_t wm8350_charger_handler(int irq, void *data)
 188 {
 189         struct wm8350 *wm8350 = data;
 190         struct wm8350_power *power = &wm8350->power;
 191         struct wm8350_charger_policy *policy = power->policy;
 192
 193         switch (irq - wm8350->irq_base) {
 194         case WM8350_IRQ_CHG_BAT_FAIL:
 195                 dev_err(wm8350->dev, "battery failed\n");
 196                 break;
 197         case WM8350_IRQ_CHG_TO:
 198                 dev_err(wm8350->dev, "charger timeout\n");
 199                 power_supply_changed(power->battery);
 200                 break;
 201
 202         case WM8350_IRQ_CHG_BAT_HOT:
 203         case WM8350_IRQ_CHG_BAT_COLD:
 204         case WM8350_IRQ_CHG_START:
 205         case WM8350_IRQ_CHG_END:
 206                 power_supply_changed(power->battery);
 207                 break;
 208
 209         case WM8350_IRQ_CHG_FAST_RDY:
 210                 dev_dbg(wm8350->dev, "fast charger ready\n");
 211                 wm8350_charger_config(wm8350, policy);
 212                 wm8350_reg_unlock(wm8350);
 213                 wm8350_set_bits(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1,
 214                                 WM8350_CHG_FAST);
 215                 wm8350_reg_lock(wm8350);
 216                 break;
 217
 218         case WM8350_IRQ_CHG_VBATT_LT_3P9:
 219                 dev_warn(wm8350->dev, "battery < 3.9V\n");
 220                 break;
 221         case WM8350_IRQ_CHG_VBATT_LT_3P1:
 222                 dev_warn(wm8350->dev, "battery < 3.1V\n");
 223                 break;
 224         case WM8350_IRQ_CHG_VBATT_LT_2P85:
 225                 dev_warn(wm8350->dev, "battery < 2.85V\n");
 226                 break;
 227
 228                 /* Supply change.  We will overnotify but it should do
 229                  * no harm. */
 230         case WM8350_IRQ_EXT_USB_FB:
 231         case WM8350_IRQ_EXT_WALL_FB:
 232                 wm8350_charger_config(wm8350, policy);
 233                 /* Fall through */
 234         case WM8350_IRQ_EXT_BAT_FB:
 235                 power_supply_changed(power->battery);
 236                 power_supply_changed(power->usb);
 237                 power_supply_changed(power->ac);
 238                 break;
 239
 240         default:
 241                 dev_err(wm8350->dev, "Unknown interrupt %d\n", irq);
 242         }
 243
 244         return IRQ_HANDLED;
 245 }
 246
 247 /*********************************************************************
 248  *              AC Power
 249  *********************************************************************/
 250 static int wm8350_ac_get_prop(struct power_supply *psy,
 251                               enum power_supply_property psp,
 252                               union power_supply_propval *val)
 253 {
 254         struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
 255         int ret = 0;
 256
 257         switch (psp) {
 258         case POWER_SUPPLY_PROP_ONLINE:
 259                 val->intval = !!(wm8350_get_supplies(wm8350) &
 260                                  WM8350_LINE_SUPPLY);
 261                 break;
 262         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 263                 val->intval = wm8350_read_line_uvolts(wm8350);
 264                 break;
 265         default:
 266                 ret = -EINVAL;
 267                 break;
 268         }
 269         return ret;
 270 }
 271
 272 static enum power_supply_property wm8350_ac_props[] = {
 273         POWER_SUPPLY_PROP_ONLINE,
 274         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 275 };
 276
 277 /*********************************************************************
 278  *              USB Power
 279  *********************************************************************/
 280 static int wm8350_usb_get_prop(struct power_supply *psy,
 281                                enum power_supply_property psp,
 282                                union power_supply_propval *val)
 283 {
 284         struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
 285         int ret = 0;
 286
 287         switch (psp) {
 288         case POWER_SUPPLY_PROP_ONLINE:
 289                 val->intval = !!(wm8350_get_supplies(wm8350) &
 290                                  WM8350_USB_SUPPLY);
 291                 break;
 292         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 293                 val->intval = wm8350_read_usb_uvolts(wm8350);
 294                 break;
 295         default:
 296                 ret = -EINVAL;
 297                 break;
 298         }
 299         return ret;
 300 }
 301
 302 static enum power_supply_property wm8350_usb_props[] = {
 303         POWER_SUPPLY_PROP_ONLINE,
 304         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 305 };
 306
 307 /*********************************************************************
 308  *              Battery properties
 309  *********************************************************************/
 310
 311 static int wm8350_bat_check_health(struct wm8350 *wm8350)
 312 {
 313         u16 reg;
 314
 315         if (wm8350_read_battery_uvolts(wm8350) < 2850000)
 316                 return POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
 317
 318         reg = wm8350_reg_read(wm8350, WM8350_CHARGER_OVERRIDES);
 319         if (reg & WM8350_CHG_BATT_HOT_OVRDE)
 320                 return POWER_SUPPLY_HEALTH_OVERHEAT;
 321
 322         if (reg & WM8350_CHG_BATT_COLD_OVRDE)
 323                 return POWER_SUPPLY_HEALTH_COLD;
 324
 325         return POWER_SUPPLY_HEALTH_GOOD;
 326 }
 327
 328 static int wm8350_bat_get_charge_type(struct wm8350 *wm8350)
 329 {
 330         int state;
 331
 332         state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2) &
 333             WM8350_CHG_STS_MASK;
 334         switch (state) {
 335         case WM8350_CHG_STS_OFF:
 336                 return POWER_SUPPLY_CHARGE_TYPE_NONE;
 337         case WM8350_CHG_STS_TRICKLE:
 338                 return POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
 339         case WM8350_CHG_STS_FAST:
 340                 return POWER_SUPPLY_CHARGE_TYPE_FAST;
 341         default:
 342                 return POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
 343         }
 344 }
 345
 346 static int wm8350_bat_get_property(struct power_supply *psy,
 347                                    enum power_supply_property psp,
 348                                    union power_supply_propval *val)
 349 {
 350         struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
 351         int ret = 0;
 352
 353         switch (psp) {
 354         case POWER_SUPPLY_PROP_STATUS:
 355                 val->intval = wm8350_batt_status(wm8350);
 356                 break;
 357         case POWER_SUPPLY_PROP_ONLINE:
 358                 val->intval = !!(wm8350_get_supplies(wm8350) &
 359                                  WM8350_BATT_SUPPLY);
 360                 break;
 361         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 362                 val->intval = wm8350_read_battery_uvolts(wm8350);
 363                 break;
 364         case POWER_SUPPLY_PROP_HEALTH:
 365                 val->intval = wm8350_bat_check_health(wm8350);
 366                 break;
 367         case POWER_SUPPLY_PROP_CHARGE_TYPE:
 368                 val->intval = wm8350_bat_get_charge_type(wm8350);
 369                 break;
 370         default:
 371                 ret = -EINVAL;
 372                 break;
 373         }
 374
 375         return ret;
 376 }
 377
 378 static enum power_supply_property wm8350_bat_props[] = {
 379         POWER_SUPPLY_PROP_STATUS,
 380         POWER_SUPPLY_PROP_ONLINE,
 381         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 382         POWER_SUPPLY_PROP_HEALTH,
 383         POWER_SUPPLY_PROP_CHARGE_TYPE,
 384 };
 385
 386 static const struct power_supply_desc wm8350_ac_desc = {
 387         .name           = "wm8350-ac",
 388         .type           = POWER_SUPPLY_TYPE_MAINS,
 389         .properties     = wm8350_ac_props,
 390         .num_properties = ARRAY_SIZE(wm8350_ac_props),
 391         .get_property   = wm8350_ac_get_prop,
 392 };
 393
 394 static const struct power_supply_desc wm8350_battery_desc = {
 395         .name           = "wm8350-battery",
 396         .properties     = wm8350_bat_props,
 397         .num_properties = ARRAY_SIZE(wm8350_bat_props),
 398         .get_property   = wm8350_bat_get_property,
 399         .use_for_apm    = 1,
 400 };
 401
 402 static const struct power_supply_desc wm8350_usb_desc = {
 403         .name           = "wm8350-usb",
 404         .type           = POWER_SUPPLY_TYPE_USB,
 405         .properties     = wm8350_usb_props,
 406         .num_properties = ARRAY_SIZE(wm8350_usb_props),
 407         .get_property   = wm8350_usb_get_prop,
 408 };
 409
 410 /*********************************************************************
 411  *              Initialisation
 412  *********************************************************************/
 413
 414 static void wm8350_init_charger(struct wm8350 *wm8350)
 415 {
 416         /* register our interest in charger events */
 417         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT,
 418                             wm8350_charger_handler, 0, "Battery hot", wm8350);
 419         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD,
 420                             wm8350_charger_handler, 0, "Battery cold", wm8350);
 421         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL,
 422                             wm8350_charger_handler, 0, "Battery fail", wm8350);
 423         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_TO,
 424                             wm8350_charger_handler, 0,
 425                             "Charger timeout", wm8350);
 426         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_END,
 427                             wm8350_charger_handler, 0,
 428                             "Charge end", wm8350);
 429         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_START,
 430                             wm8350_charger_handler, 0,
 431                             "Charge start", wm8350);
 432         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_FAST_RDY,
 433                             wm8350_charger_handler, 0,
 434                             "Fast charge ready", wm8350);
 435         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9,
 436                             wm8350_charger_handler, 0,
 437                             "Battery <3.9V", wm8350);
 438         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1,
 439                             wm8350_charger_handler, 0,
 440                             "Battery <3.1V", wm8350);
 441         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85,
 442                             wm8350_charger_handler, 0,
 443                             "Battery <2.85V", wm8350);
 444
 445         /* and supply change events */
 446         wm8350_register_irq(wm8350, WM8350_IRQ_EXT_USB_FB,
 447                             wm8350_charger_handler, 0, "USB", wm8350);
 448         wm8350_register_irq(wm8350, WM8350_IRQ_EXT_WALL_FB,
 449                             wm8350_charger_handler, 0, "Wall", wm8350);
 450         wm8350_register_irq(wm8350, WM8350_IRQ_EXT_BAT_FB,
 451                             wm8350_charger_handler, 0, "Battery", wm8350);
 452 }
 453
 454 static void free_charger_irq(struct wm8350 *wm8350)
 455 {
 456         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT, wm8350);
 457         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD, wm8350);
 458         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL, wm8350);
 459         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_TO, wm8350);
 460         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_END, wm8350);
 461         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_START, wm8350);
 462         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9, wm8350);
 463         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1, wm8350);
 464         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85, wm8350);
 465         wm8350_free_irq(wm8350, WM8350_IRQ_EXT_USB_FB, wm8350);
 466         wm8350_free_irq(wm8350, WM8350_IRQ_EXT_WALL_FB, wm8350);
 467         wm8350_free_irq(wm8350, WM8350_IRQ_EXT_BAT_FB, wm8350);
 468 }
 469
 470 static int wm8350_power_probe(struct platform_device *pdev)
 471 {
 472         struct wm8350 *wm8350 = platform_get_drvdata(pdev);
 473         struct wm8350_power *power = &wm8350->power;
 474         struct wm8350_charger_policy *policy = power->policy;
 475         int ret;
 476
 477         power->ac = power_supply_register(&pdev->dev, &wm8350_ac_desc, NULL);
 478         if (IS_ERR(power->ac))
 479                 return PTR_ERR(power->ac);
 480
 481         power->battery = power_supply_register(&pdev->dev, &wm8350_battery_desc,
 482                                                NULL);
 483         if (IS_ERR(power->battery)) {
 484                 ret = PTR_ERR(power->battery);
 485                 goto battery_failed;
 486         }
 487
 488         power->usb = power_supply_register(&pdev->dev, &wm8350_usb_desc, NULL);
 489         if (IS_ERR(power->usb)) {
 490                 ret = PTR_ERR(power->usb);
 491                 goto usb_failed;
 492         }
 493
 494         ret = device_create_file(&pdev->dev, &dev_attr_charger_state);
 495         if (ret < 0)
 496                 dev_warn(wm8350->dev, "failed to add charge sysfs: %d\n", ret);
 497         ret = 0;
 498
 499         wm8350_init_charger(wm8350);
 500         if (wm8350_charger_config(wm8350, policy) == 0) {
 501                 wm8350_reg_unlock(wm8350);
 502                 wm8350_set_bits(wm8350, WM8350_POWER_MGMT_5, WM8350_CHG_ENA);
 503                 wm8350_reg_lock(wm8350);
 504         }
 505
 506         return ret;
 507
 508 usb_failed:
 509         power_supply_unregister(power->battery);
 510 battery_failed:
 511         power_supply_unregister(power->ac);
 512
 513         return ret;
 514 }
 515
 516 static int wm8350_power_remove(struct platform_device *pdev)
 517 {
 518         struct wm8350 *wm8350 = platform_get_drvdata(pdev);
 519         struct wm8350_power *power = &wm8350->power;
 520
 521         free_charger_irq(wm8350);
 522         device_remove_file(&pdev->dev, &dev_attr_charger_state);
 523         power_supply_unregister(power->battery);
 524         power_supply_unregister(power->ac);
 525         power_supply_unregister(power->usb);
 526         return 0;
 527 }
 528
 529 static struct platform_driver wm8350_power_driver = {
 530         .probe = wm8350_power_probe,
 531         .remove = wm8350_power_remove,
 532         .driver = {
 533                 .name = "wm8350-power",
 534         },
 535 };
 536
 537 module_platform_driver(wm8350_power_driver);
 538
 539 MODULE_LICENSE("GPL");
 540 MODULE_DESCRIPTION("Power supply driver for WM8350");
 541 MODULE_ALIAS("platform:wm8350-power");