kernel/drivers/power/isp1704_charger.c

   1 /*
   2  * ISP1704 USB Charger Detection driver
   3  *
   4  * Copyright (C) 2010 Nokia Corporation
   5  * Copyright (C) 2012 - 2013 Pali Rohár <pali.rohar@gmail.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/err.h>
  25 #include <linux/init.h>
  26 #include <linux/types.h>
  27 #include <linux/device.h>
  28 #include <linux/sysfs.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/power_supply.h>
  31 #include <linux/delay.h>
  32 #include <linux/of.h>
  33 #include <linux/of_gpio.h>
  34
  35 #include <linux/usb/otg.h>
  36 #include <linux/usb/ulpi.h>
  37 #include <linux/usb/ch9.h>
  38 #include <linux/usb/gadget.h>
  39 #include <linux/power/isp1704_charger.h>
  40
  41 /* Vendor specific Power Control register */
  42 #define ISP1704_PWR_CTRL                0x3d
  43 #define ISP1704_PWR_CTRL_SWCTRL         (1 << 0)
  44 #define ISP1704_PWR_CTRL_DET_COMP       (1 << 1)
  45 #define ISP1704_PWR_CTRL_BVALID_RISE    (1 << 2)
  46 #define ISP1704_PWR_CTRL_BVALID_FALL    (1 << 3)
  47 #define ISP1704_PWR_CTRL_DP_WKPU_EN     (1 << 4)
  48 #define ISP1704_PWR_CTRL_VDAT_DET       (1 << 5)
  49 #define ISP1704_PWR_CTRL_DPVSRC_EN      (1 << 6)
  50 #define ISP1704_PWR_CTRL_HWDETECT       (1 << 7)
  51
  52 #define NXP_VENDOR_ID                   0x04cc
  53
  54 static u16 isp170x_id[] = {
  55         0x1704,
  56         0x1707,
  57 };
  58
  59 struct isp1704_charger {
  60         struct device                   *dev;
  61         struct power_supply             *psy;
  62         struct power_supply_desc        psy_desc;
  63         struct usb_phy                  *phy;
  64         struct notifier_block           nb;
  65         struct work_struct              work;
  66
  67         /* properties */
  68         char                    model[8];
  69         unsigned                present:1;
  70         unsigned                online:1;
  71         unsigned                current_max;
  72 };
  73
  74 static inline int isp1704_read(struct isp1704_charger *isp, u32 reg)
  75 {
  76         return usb_phy_io_read(isp->phy, reg);
  77 }
  78
  79 static inline int isp1704_write(struct isp1704_charger *isp, u32 val, u32 reg)
  80 {
  81         return usb_phy_io_write(isp->phy, val, reg);
  82 }
  83
  84 /*
  85  * Disable/enable the power from the isp1704 if a function for it
  86  * has been provided with platform data.
  87  */
  88 static void isp1704_charger_set_power(struct isp1704_charger *isp, bool on)
  89 {
  90         struct isp1704_charger_data     *board = isp->dev->platform_data;
  91
  92         if (board && board->set_power)
  93                 board->set_power(on);
  94         else if (board)
  95                 gpio_set_value(board->enable_gpio, on);
  96 }
  97
  98 /*
  99  * Determine is the charging port DCP (dedicated charger) or CDP (Host/HUB
 100  * chargers).
 101  *
 102  * REVISIT: The method is defined in Battery Charging Specification and is
 103  * applicable to any ULPI transceiver. Nothing isp170x specific here.
 104  */
 105 static inline int isp1704_charger_type(struct isp1704_charger *isp)
 106 {
 107         u8 reg;
 108         u8 func_ctrl;
 109         u8 otg_ctrl;
 110         int type = POWER_SUPPLY_TYPE_USB_DCP;
 111
 112         func_ctrl = isp1704_read(isp, ULPI_FUNC_CTRL);
 113         otg_ctrl = isp1704_read(isp, ULPI_OTG_CTRL);
 114
 115         /* disable pulldowns */
 116         reg = ULPI_OTG_CTRL_DM_PULLDOWN | ULPI_OTG_CTRL_DP_PULLDOWN;
 117         isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), reg);
 118
 119         /* full speed */
 120         isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
 121                         ULPI_FUNC_CTRL_XCVRSEL_MASK);
 122         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL),
 123                         ULPI_FUNC_CTRL_FULL_SPEED);
 124
 125         /* Enable strong pull-up on DP (1.5K) and reset */
 126         reg = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
 127         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), reg);
 128         usleep_range(1000, 2000);
 129
 130         reg = isp1704_read(isp, ULPI_DEBUG);
 131         if ((reg & 3) != 3)
 132                 type = POWER_SUPPLY_TYPE_USB_CDP;
 133
 134         /* recover original state */
 135         isp1704_write(isp, ULPI_FUNC_CTRL, func_ctrl);
 136         isp1704_write(isp, ULPI_OTG_CTRL, otg_ctrl);
 137
 138         return type;
 139 }
 140
 141 /*
 142  * ISP1704 detects PS/2 adapters as charger. To make sure the detected charger
 143  * is actually a dedicated charger, the following steps need to be taken.
 144  */
 145 static inline int isp1704_charger_verify(struct isp1704_charger *isp)
 146 {
 147         int     ret = 0;
 148         u8      r;
 149
 150         /* Reset the transceiver */
 151         r = isp1704_read(isp, ULPI_FUNC_CTRL);
 152         r |= ULPI_FUNC_CTRL_RESET;
 153         isp1704_write(isp, ULPI_FUNC_CTRL, r);
 154         usleep_range(1000, 2000);
 155
 156         /* Set normal mode */
 157         r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK);
 158         isp1704_write(isp, ULPI_FUNC_CTRL, r);
 159
 160         /* Clear the DP and DM pull-down bits */
 161         r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN;
 162         isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), r);
 163
 164         /* Enable strong pull-up on DP (1.5K) and reset */
 165         r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
 166         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), r);
 167         usleep_range(1000, 2000);
 168
 169         /* Read the line state */
 170         if (!isp1704_read(isp, ULPI_DEBUG)) {
 171                 /* Disable strong pull-up on DP (1.5K) */
 172                 isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
 173                                 ULPI_FUNC_CTRL_TERMSELECT);
 174                 return 1;
 175         }
 176
 177         /* Is it a charger or PS/2 connection */
 178
 179         /* Enable weak pull-up resistor on DP */
 180         isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
 181                         ISP1704_PWR_CTRL_DP_WKPU_EN);
 182
 183         /* Disable strong pull-up on DP (1.5K) */
 184         isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
 185                         ULPI_FUNC_CTRL_TERMSELECT);
 186
 187         /* Enable weak pull-down resistor on DM */
 188         isp1704_write(isp, ULPI_SET(ULPI_OTG_CTRL),
 189                         ULPI_OTG_CTRL_DM_PULLDOWN);
 190
 191         /* It's a charger if the line states are clear */
 192         if (!(isp1704_read(isp, ULPI_DEBUG)))
 193                 ret = 1;
 194
 195         /* Disable weak pull-up resistor on DP */
 196         isp1704_write(isp, ULPI_CLR(ISP1704_PWR_CTRL),
 197                         ISP1704_PWR_CTRL_DP_WKPU_EN);
 198
 199         return ret;
 200 }
 201
 202 static inline int isp1704_charger_detect(struct isp1704_charger *isp)
 203 {
 204         unsigned long   timeout;
 205         u8              pwr_ctrl;
 206         int             ret = 0;
 207
 208         pwr_ctrl = isp1704_read(isp, ISP1704_PWR_CTRL);
 209
 210         /* set SW control bit in PWR_CTRL register */
 211         isp1704_write(isp, ISP1704_PWR_CTRL,
 212                         ISP1704_PWR_CTRL_SWCTRL);
 213
 214         /* enable manual charger detection */
 215         isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
 216                         ISP1704_PWR_CTRL_SWCTRL
 217                         | ISP1704_PWR_CTRL_DPVSRC_EN);
 218         usleep_range(1000, 2000);
 219
 220         timeout = jiffies + msecs_to_jiffies(300);
 221         do {
 222                 /* Check if there is a charger */
 223                 if (isp1704_read(isp, ISP1704_PWR_CTRL)
 224                                 & ISP1704_PWR_CTRL_VDAT_DET) {
 225                         ret = isp1704_charger_verify(isp);
 226                         break;
 227                 }
 228         } while (!time_after(jiffies, timeout) && isp->online);
 229
 230         /* recover original state */
 231         isp1704_write(isp, ISP1704_PWR_CTRL, pwr_ctrl);
 232
 233         return ret;
 234 }
 235
 236 static inline int isp1704_charger_detect_dcp(struct isp1704_charger *isp)
 237 {
 238         if (isp1704_charger_detect(isp) &&
 239                         isp1704_charger_type(isp) == POWER_SUPPLY_TYPE_USB_DCP)
 240                 return true;
 241         else
 242                 return false;
 243 }
 244
 245 static void isp1704_charger_work(struct work_struct *data)
 246 {
 247         struct isp1704_charger  *isp =
 248                 container_of(data, struct isp1704_charger, work);
 249         static DEFINE_MUTEX(lock);
 250
 251         mutex_lock(&lock);
 252
 253         switch (isp->phy->last_event) {
 254         case USB_EVENT_VBUS:
 255                 /* do not call wall charger detection more times */
 256                 if (!isp->present) {
 257                         isp->online = true;
 258                         isp->present = 1;
 259                         isp1704_charger_set_power(isp, 1);
 260
 261                         /* detect wall charger */
 262                         if (isp1704_charger_detect_dcp(isp)) {
 263                                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB_DCP;
 264                                 isp->current_max = 1800;
 265                         } else {
 266                                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB;
 267                                 isp->current_max = 500;
 268                         }
 269
 270                         /* enable data pullups */
 271                         if (isp->phy->otg->gadget)
 272                                 usb_gadget_connect(isp->phy->otg->gadget);
 273                 }
 274
 275                 if (isp->psy_desc.type != POWER_SUPPLY_TYPE_USB_DCP) {
 276                         /*
 277                          * Only 500mA here or high speed chirp
 278                          * handshaking may break
 279                          */
 280                         if (isp->current_max > 500)
 281                                 isp->current_max = 500;
 282
 283                         if (isp->current_max > 100)
 284                                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB_CDP;
 285                 }
 286                 break;
 287         case USB_EVENT_NONE:
 288                 isp->online = false;
 289                 isp->present = 0;
 290                 isp->current_max = 0;
 291                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB;
 292
 293                 /*
 294                  * Disable data pullups. We need to prevent the controller from
 295                  * enumerating.
 296                  *
 297                  * FIXME: This is here to allow charger detection with Host/HUB
 298                  * chargers. The pullups may be enabled elsewhere, so this can
 299                  * not be the final solution.
 300                  */
 301                 if (isp->phy->otg->gadget)
 302                         usb_gadget_disconnect(isp->phy->otg->gadget);
 303
 304                 isp1704_charger_set_power(isp, 0);
 305                 break;
 306         default:
 307                 goto out;
 308         }
 309
 310         power_supply_changed(isp->psy);
 311 out:
 312         mutex_unlock(&lock);
 313 }
 314
 315 static int isp1704_notifier_call(struct notifier_block *nb,
 316                 unsigned long val, void *v)
 317 {
 318         struct isp1704_charger *isp =
 319                 container_of(nb, struct isp1704_charger, nb);
 320
 321         schedule_work(&isp->work);
 322
 323         return NOTIFY_OK;
 324 }
 325
 326 static int isp1704_charger_get_property(struct power_supply *psy,
 327                                 enum power_supply_property psp,
 328                                 union power_supply_propval *val)
 329 {
 330         struct isp1704_charger *isp = power_supply_get_drvdata(psy);
 331
 332         switch (psp) {
 333         case POWER_SUPPLY_PROP_PRESENT:
 334                 val->intval = isp->present;
 335                 break;
 336         case POWER_SUPPLY_PROP_ONLINE:
 337                 val->intval = isp->online;
 338                 break;
 339         case POWER_SUPPLY_PROP_CURRENT_MAX:
 340                 val->intval = isp->current_max;
 341                 break;
 342         case POWER_SUPPLY_PROP_MODEL_NAME:
 343                 val->strval = isp->model;
 344                 break;
 345         case POWER_SUPPLY_PROP_MANUFACTURER:
 346                 val->strval = "NXP";
 347                 break;
 348         default:
 349                 return -EINVAL;
 350         }
 351         return 0;
 352 }
 353
 354 static enum power_supply_property power_props[] = {
 355         POWER_SUPPLY_PROP_PRESENT,
 356         POWER_SUPPLY_PROP_ONLINE,
 357         POWER_SUPPLY_PROP_CURRENT_MAX,
 358         POWER_SUPPLY_PROP_MODEL_NAME,
 359         POWER_SUPPLY_PROP_MANUFACTURER,
 360 };
 361
 362 static inline int isp1704_test_ulpi(struct isp1704_charger *isp)
 363 {
 364         int vendor;
 365         int product;
 366         int i;
 367         int ret = -ENODEV;
 368
 369         /* Test ULPI interface */
 370         ret = isp1704_write(isp, ULPI_SCRATCH, 0xaa);
 371         if (ret < 0)
 372                 return ret;
 373
 374         ret = isp1704_read(isp, ULPI_SCRATCH);
 375         if (ret < 0)
 376                 return ret;
 377
 378         if (ret != 0xaa)
 379                 return -ENODEV;
 380
 381         /* Verify the product and vendor id matches */
 382         vendor = isp1704_read(isp, ULPI_VENDOR_ID_LOW);
 383         vendor |= isp1704_read(isp, ULPI_VENDOR_ID_HIGH) << 8;
 384         if (vendor != NXP_VENDOR_ID)
 385                 return -ENODEV;
 386
 387         product = isp1704_read(isp, ULPI_PRODUCT_ID_LOW);
 388         product |= isp1704_read(isp, ULPI_PRODUCT_ID_HIGH) << 8;
 389
 390         for (i = 0; i < ARRAY_SIZE(isp170x_id); i++) {
 391                 if (product == isp170x_id[i]) {
 392                         sprintf(isp->model, "isp%x", product);
 393                         return product;
 394                 }
 395         }
 396
 397         dev_err(isp->dev, "product id %x not matching known ids", product);
 398
 399         return -ENODEV;
 400 }
 401
 402 static int isp1704_charger_probe(struct platform_device *pdev)
 403 {
 404         struct isp1704_charger  *isp;
 405         int                     ret = -ENODEV;
 406         struct power_supply_config psy_cfg = {};
 407
 408         struct isp1704_charger_data *pdata = dev_get_platdata(&pdev->dev);
 409         struct device_node *np = pdev->dev.of_node;
 410
 411         if (np) {
 412                 int gpio = of_get_named_gpio(np, "nxp,enable-gpio", 0);
 413
 414                 if (gpio < 0)
 415                         return gpio;
 416
 417                 pdata = devm_kzalloc(&pdev->dev,
 418                         sizeof(struct isp1704_charger_data), GFP_KERNEL);
 419                 pdata->enable_gpio = gpio;
 420
 421                 dev_info(&pdev->dev, "init gpio %d\n", pdata->enable_gpio);
 422
 423                 ret = devm_gpio_request_one(&pdev->dev, pdata->enable_gpio,
 424                                         GPIOF_OUT_INIT_HIGH, "isp1704_reset");
 425                 if (ret)
 426                         goto fail0;
 427         }
 428
 429         if (!pdata) {
 430                 dev_err(&pdev->dev, "missing platform data!\n");
 431                 return -ENODEV;
 432         }
 433
 434
 435         isp = devm_kzalloc(&pdev->dev, sizeof(*isp), GFP_KERNEL);
 436         if (!isp)
 437                 return -ENOMEM;
 438
 439         if (np)
 440                 isp->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "usb-phy", 0);
 441         else
 442                 isp->phy = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
 443
 444         if (IS_ERR(isp->phy)) {
 445                 ret = PTR_ERR(isp->phy);
 446                 goto fail0;
 447         }
 448
 449         isp->dev = &pdev->dev;
 450         platform_set_drvdata(pdev, isp);
 451
 452         isp1704_charger_set_power(isp, 1);
 453
 454         ret = isp1704_test_ulpi(isp);
 455         if (ret < 0)
 456                 goto fail1;
 457
 458         isp->psy_desc.name              = "isp1704";
 459         isp->psy_desc.type              = POWER_SUPPLY_TYPE_USB;
 460         isp->psy_desc.properties        = power_props;
 461         isp->psy_desc.num_properties    = ARRAY_SIZE(power_props);
 462         isp->psy_desc.get_property      = isp1704_charger_get_property;
 463
 464         psy_cfg.drv_data                = isp;
 465
 466         isp->psy = power_supply_register(isp->dev, &isp->psy_desc, &psy_cfg);
 467         if (IS_ERR(isp->psy)) {
 468                 ret = PTR_ERR(isp->psy);
 469                 goto fail1;
 470         }
 471
 472         /*
 473          * REVISIT: using work in order to allow the usb notifications to be
 474          * made atomically in the future.
 475          */
 476         INIT_WORK(&isp->work, isp1704_charger_work);
 477
 478         isp->nb.notifier_call = isp1704_notifier_call;
 479
 480         ret = usb_register_notifier(isp->phy, &isp->nb);
 481         if (ret)
 482                 goto fail2;
 483
 484         dev_info(isp->dev, "registered with product id %s\n", isp->model);
 485
 486         /*
 487          * Taking over the D+ pullup.
 488          *
 489          * FIXME: The device will be disconnected if it was already
 490          * enumerated. The charger driver should be always loaded before any
 491          * gadget is loaded.
 492          */
 493         if (isp->phy->otg->gadget)
 494                 usb_gadget_disconnect(isp->phy->otg->gadget);
 495
 496         if (isp->phy->last_event == USB_EVENT_NONE)
 497                 isp1704_charger_set_power(isp, 0);
 498
 499         /* Detect charger if VBUS is valid (the cable was already plugged). */
 500         if (isp->phy->last_event == USB_EVENT_VBUS &&
 501                         !isp->phy->otg->default_a)
 502                 schedule_work(&isp->work);
 503
 504         return 0;
 505 fail2:
 506         power_supply_unregister(isp->psy);
 507 fail1:
 508         isp1704_charger_set_power(isp, 0);
 509 fail0:
 510         dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret);
 511
 512         return ret;
 513 }
 514
 515 static int isp1704_charger_remove(struct platform_device *pdev)
 516 {
 517         struct isp1704_charger *isp = platform_get_drvdata(pdev);
 518
 519         usb_unregister_notifier(isp->phy, &isp->nb);
 520         power_supply_unregister(isp->psy);
 521         isp1704_charger_set_power(isp, 0);
 522
 523         return 0;
 524 }
 525
 526 #ifdef CONFIG_OF
 527 static const struct of_device_id omap_isp1704_of_match[] = {
 528         { .compatible = "nxp,isp1704", },
 529         {},
 530 };
 531 MODULE_DEVICE_TABLE(of, omap_isp1704_of_match);
 532 #endif
 533
 534 static struct platform_driver isp1704_charger_driver = {
 535         .driver = {
 536                 .name = "isp1704_charger",
 537                 .of_match_table = of_match_ptr(omap_isp1704_of_match),
 538         },
 539         .probe = isp1704_charger_probe,
 540         .remove = isp1704_charger_remove,
 541 };
 542
 543 module_platform_driver(isp1704_charger_driver);
 544
 545 MODULE_ALIAS("platform:isp1704_charger");
 546 MODULE_AUTHOR("Nokia Corporation");
 547 MODULE_DESCRIPTION("ISP170x USB Charger driver");
 548 MODULE_LICENSE("GPL");