drivers/power/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(charger_state, 0444, charger_state_show, NULL);
 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         case WM8350_IRQ_EXT_BAT_FB:   /* Fall through */
 234                 power_supply_changed(power->battery);
 235                 power_supply_changed(power->usb);
 236                 power_supply_changed(power->ac);
 237                 break;
 238
 239         default:
 240                 dev_err(wm8350->dev, "Unknown interrupt %d\n", irq);
 241         }
 242
 243         return IRQ_HANDLED;
 244 }
 245
 246 /*********************************************************************
 247  *              AC Power
 248  *********************************************************************/
 249 static int wm8350_ac_get_prop(struct power_supply *psy,
 250                               enum power_supply_property psp,
 251                               union power_supply_propval *val)
 252 {
 253         struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
 254         int ret = 0;
 255
 256         switch (psp) {
 257         case POWER_SUPPLY_PROP_ONLINE:
 258                 val->intval = !!(wm8350_get_supplies(wm8350) &
 259                                  WM8350_LINE_SUPPLY);
 260                 break;
 261         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 262                 val->intval = wm8350_read_line_uvolts(wm8350);
 263                 break;
 264         default:
 265                 ret = -EINVAL;
 266                 break;
 267         }
 268         return ret;
 269 }
 270
 271 static enum power_supply_property wm8350_ac_props[] = {
 272         POWER_SUPPLY_PROP_ONLINE,
 273         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 274 };
 275
 276 /*********************************************************************
 277  *              USB Power
 278  *********************************************************************/
 279 static int wm8350_usb_get_prop(struct power_supply *psy,
 280                                enum power_supply_property psp,
 281                                union power_supply_propval *val)
 282 {
 283         struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
 284         int ret = 0;
 285
 286         switch (psp) {
 287         case POWER_SUPPLY_PROP_ONLINE:
 288                 val->intval = !!(wm8350_get_supplies(wm8350) &
 289                                  WM8350_USB_SUPPLY);
 290                 break;
 291         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 292                 val->intval = wm8350_read_usb_uvolts(wm8350);
 293                 break;
 294         default:
 295                 ret = -EINVAL;
 296                 break;
 297         }
 298         return ret;
 299 }
 300
 301 static enum power_supply_property wm8350_usb_props[] = {
 302         POWER_SUPPLY_PROP_ONLINE,
 303         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 304 };
 305
 306 /*********************************************************************
 307  *              Battery properties
 308  *********************************************************************/
 309
 310 static int wm8350_bat_check_health(struct wm8350 *wm8350)
 311 {
 312         u16 reg;
 313
 314         if (wm8350_read_battery_uvolts(wm8350) < 2850000)
 315                 return POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
 316
 317         reg = wm8350_reg_read(wm8350, WM8350_CHARGER_OVERRIDES);
 318         if (reg & WM8350_CHG_BATT_HOT_OVRDE)
 319                 return POWER_SUPPLY_HEALTH_OVERHEAT;
 320
 321         if (reg & WM8350_CHG_BATT_COLD_OVRDE)
 322                 return POWER_SUPPLY_HEALTH_COLD;
 323
 324         return POWER_SUPPLY_HEALTH_GOOD;
 325 }
 326
 327 static int wm8350_bat_get_charge_type(struct wm8350 *wm8350)
 328 {
 329         int state;
 330
 331         state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2) &
 332             WM8350_CHG_STS_MASK;
 333         switch (state) {
 334         case WM8350_CHG_STS_OFF:
 335                 return POWER_SUPPLY_CHARGE_TYPE_NONE;
 336         case WM8350_CHG_STS_TRICKLE:
 337                 return POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
 338         case WM8350_CHG_STS_FAST:
 339                 return POWER_SUPPLY_CHARGE_TYPE_FAST;
 340         default:
 341                 return POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
 342         }
 343 }
 344
 345 static int wm8350_bat_get_property(struct power_supply *psy,
 346                                    enum power_supply_property psp,
 347                                    union power_supply_propval *val)
 348 {
 349         struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
 350         int ret = 0;
 351
 352         switch (psp) {
 353         case POWER_SUPPLY_PROP_STATUS:
 354                 val->intval = wm8350_batt_status(wm8350);
 355                 break;
 356         case POWER_SUPPLY_PROP_ONLINE:
 357                 val->intval = !!(wm8350_get_supplies(wm8350) &
 358                                  WM8350_BATT_SUPPLY);
 359                 break;
 360         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 361                 val->intval = wm8350_read_battery_uvolts(wm8350);
 362                 break;
 363         case POWER_SUPPLY_PROP_HEALTH:
 364                 val->intval = wm8350_bat_check_health(wm8350);
 365                 break;
 366         case POWER_SUPPLY_PROP_CHARGE_TYPE:
 367                 val->intval = wm8350_bat_get_charge_type(wm8350);
 368                 break;
 369         default:
 370                 ret = -EINVAL;
 371                 break;
 372         }
 373
 374         return ret;
 375 }
 376
 377 static enum power_supply_property wm8350_bat_props[] = {
 378         POWER_SUPPLY_PROP_STATUS,
 379         POWER_SUPPLY_PROP_ONLINE,
 380         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 381         POWER_SUPPLY_PROP_HEALTH,
 382         POWER_SUPPLY_PROP_CHARGE_TYPE,
 383 };
 384
 385 static const struct power_supply_desc wm8350_ac_desc = {
 386         .name           = "wm8350-ac",
 387         .type           = POWER_SUPPLY_TYPE_MAINS,
 388         .properties     = wm8350_ac_props,
 389         .num_properties = ARRAY_SIZE(wm8350_ac_props),
 390         .get_property   = wm8350_ac_get_prop,
 391 };
 392
 393 static const struct power_supply_desc wm8350_battery_desc = {
 394         .name           = "wm8350-battery",
 395         .properties     = wm8350_bat_props,
 396         .num_properties = ARRAY_SIZE(wm8350_bat_props),
 397         .get_property   = wm8350_bat_get_property,
 398         .use_for_apm    = 1,
 399 };
 400
 401 static const struct power_supply_desc wm8350_usb_desc = {
 402         .name           = "wm8350-usb",
 403         .type           = POWER_SUPPLY_TYPE_USB,
 404         .properties     = wm8350_usb_props,
 405         .num_properties = ARRAY_SIZE(wm8350_usb_props),
 406         .get_property   = wm8350_usb_get_prop,
 407 };
 408
 409 /*********************************************************************
 410  *              Initialisation
 411  *********************************************************************/
 412
 413 static void wm8350_init_charger(struct wm8350 *wm8350)
 414 {
 415         /* register our interest in charger events */
 416         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT,
 417                             wm8350_charger_handler, 0, "Battery hot", wm8350);
 418         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD,
 419                             wm8350_charger_handler, 0, "Battery cold", wm8350);
 420         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL,
 421                             wm8350_charger_handler, 0, "Battery fail", wm8350);
 422         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_TO,
 423                             wm8350_charger_handler, 0,
 424                             "Charger timeout", wm8350);
 425         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_END,
 426                             wm8350_charger_handler, 0,
 427                             "Charge end", wm8350);
 428         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_START,
 429                             wm8350_charger_handler, 0,
 430                             "Charge start", wm8350);
 431         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_FAST_RDY,
 432                             wm8350_charger_handler, 0,
 433                             "Fast charge ready", wm8350);
 434         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9,
 435                             wm8350_charger_handler, 0,
 436                             "Battery <3.9V", wm8350);
 437         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1,
 438                             wm8350_charger_handler, 0,
 439                             "Battery <3.1V", wm8350);
 440         wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85,
 441                             wm8350_charger_handler, 0,
 442                             "Battery <2.85V", wm8350);
 443
 444         /* and supply change events */
 445         wm8350_register_irq(wm8350, WM8350_IRQ_EXT_USB_FB,
 446                             wm8350_charger_handler, 0, "USB", wm8350);
 447         wm8350_register_irq(wm8350, WM8350_IRQ_EXT_WALL_FB,
 448                             wm8350_charger_handler, 0, "Wall", wm8350);
 449         wm8350_register_irq(wm8350, WM8350_IRQ_EXT_BAT_FB,
 450                             wm8350_charger_handler, 0, "Battery", wm8350);
 451 }
 452
 453 static void free_charger_irq(struct wm8350 *wm8350)
 454 {
 455         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT, wm8350);
 456         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD, wm8350);
 457         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL, wm8350);
 458         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_TO, wm8350);
 459         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_END, wm8350);
 460         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_START, wm8350);
 461         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9, wm8350);
 462         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1, wm8350);
 463         wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85, wm8350);
 464         wm8350_free_irq(wm8350, WM8350_IRQ_EXT_USB_FB, wm8350);
 465         wm8350_free_irq(wm8350, WM8350_IRQ_EXT_WALL_FB, wm8350);
 466         wm8350_free_irq(wm8350, WM8350_IRQ_EXT_BAT_FB, wm8350);
 467 }
 468
 469 static int wm8350_power_probe(struct platform_device *pdev)
 470 {
 471         struct wm8350 *wm8350 = platform_get_drvdata(pdev);
 472         struct wm8350_power *power = &wm8350->power;
 473         struct wm8350_charger_policy *policy = power->policy;
 474         int ret;
 475
 476         power->ac = power_supply_register(&pdev->dev, &wm8350_ac_desc, NULL);
 477         if (IS_ERR(power->ac))
 478                 return PTR_ERR(power->ac);
 479
 480         power->battery = power_supply_register(&pdev->dev, &wm8350_battery_desc,
 481                                                NULL);
 482         if (IS_ERR(power->battery)) {
 483                 ret = PTR_ERR(power->battery);
 484                 goto battery_failed;
 485         }
 486
 487         power->usb = power_supply_register(&pdev->dev, &wm8350_usb_desc, NULL);
 488         if (IS_ERR(power->usb)) {
 489                 ret = PTR_ERR(power->usb);
 490                 goto usb_failed;
 491         }
 492
 493         ret = device_create_file(&pdev->dev, &dev_attr_charger_state);
 494         if (ret < 0)
 495                 dev_warn(wm8350->dev, "failed to add charge sysfs: %d\n", ret);
 496         ret = 0;
 497
 498         wm8350_init_charger(wm8350);
 499         if (wm8350_charger_config(wm8350, policy) == 0) {
 500                 wm8350_reg_unlock(wm8350);
 501                 wm8350_set_bits(wm8350, WM8350_POWER_MGMT_5, WM8350_CHG_ENA);
 502                 wm8350_reg_lock(wm8350);
 503         }
 504
 505         return ret;
 506
 507 usb_failed:
 508         power_supply_unregister(power->battery);
 509 battery_failed:
 510         power_supply_unregister(power->ac);
 511
 512         return ret;
 513 }
 514
 515 static int wm8350_power_remove(struct platform_device *pdev)
 516 {
 517         struct wm8350 *wm8350 = platform_get_drvdata(pdev);
 518         struct wm8350_power *power = &wm8350->power;
 519
 520         free_charger_irq(wm8350);
 521         device_remove_file(&pdev->dev, &dev_attr_charger_state);
 522         power_supply_unregister(power->battery);
 523         power_supply_unregister(power->ac);
 524         power_supply_unregister(power->usb);
 525         return 0;
 526 }
 527
 528 static struct platform_driver wm8350_power_driver = {
 529         .probe = wm8350_power_probe,
 530         .remove = wm8350_power_remove,
 531         .driver = {
 532                 .name = "wm8350-power",
 533         },
 534 };
 535
 536 module_platform_driver(wm8350_power_driver);
 537
 538 MODULE_LICENSE("GPL");
 539 MODULE_DESCRIPTION("Power supply driver for WM8350");
 540 MODULE_ALIAS("platform:wm8350-power");