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 usb_phy          *phy;
  63         struct notifier_block   nb;
  64         struct work_struct      work;
  65
  66         /* properties */
  67         char                    model[8];
  68         unsigned                present:1;
  69         unsigned                online:1;
  70         unsigned                current_max;
  71 };
  72
  73 static inline int isp1704_read(struct isp1704_charger *isp, u32 reg)
  74 {
  75         return usb_phy_io_read(isp->phy, reg);
  76 }
  77
  78 static inline int isp1704_write(struct isp1704_charger *isp, u32 val, u32 reg)
  79 {
  80         return usb_phy_io_write(isp->phy, val, reg);
  81 }
  82
  83 /*
  84  * Disable/enable the power from the isp1704 if a function for it
  85  * has been provided with platform data.
  86  */
  87 static void isp1704_charger_set_power(struct isp1704_charger *isp, bool on)
  88 {
  89         struct isp1704_charger_data     *board = isp->dev->platform_data;
  90
  91         if (board && board->set_power)
  92                 board->set_power(on);
  93         else if (board)
  94                 gpio_set_value(board->enable_gpio, on);
  95 }
  96
  97 /*
  98  * Determine is the charging port DCP (dedicated charger) or CDP (Host/HUB
  99  * chargers).
 100  *
 101  * REVISIT: The method is defined in Battery Charging Specification and is
 102  * applicable to any ULPI transceiver. Nothing isp170x specific here.
 103  */
 104 static inline int isp1704_charger_type(struct isp1704_charger *isp)
 105 {
 106         u8 reg;
 107         u8 func_ctrl;
 108         u8 otg_ctrl;
 109         int type = POWER_SUPPLY_TYPE_USB_DCP;
 110
 111         func_ctrl = isp1704_read(isp, ULPI_FUNC_CTRL);
 112         otg_ctrl = isp1704_read(isp, ULPI_OTG_CTRL);
 113
 114         /* disable pulldowns */
 115         reg = ULPI_OTG_CTRL_DM_PULLDOWN | ULPI_OTG_CTRL_DP_PULLDOWN;
 116         isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), reg);
 117
 118         /* full speed */
 119         isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
 120                         ULPI_FUNC_CTRL_XCVRSEL_MASK);
 121         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL),
 122                         ULPI_FUNC_CTRL_FULL_SPEED);
 123
 124         /* Enable strong pull-up on DP (1.5K) and reset */
 125         reg = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
 126         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), reg);
 127         usleep_range(1000, 2000);
 128
 129         reg = isp1704_read(isp, ULPI_DEBUG);
 130         if ((reg & 3) != 3)
 131                 type = POWER_SUPPLY_TYPE_USB_CDP;
 132
 133         /* recover original state */
 134         isp1704_write(isp, ULPI_FUNC_CTRL, func_ctrl);
 135         isp1704_write(isp, ULPI_OTG_CTRL, otg_ctrl);
 136
 137         return type;
 138 }
 139
 140 /*
 141  * ISP1704 detects PS/2 adapters as charger. To make sure the detected charger
 142  * is actually a dedicated charger, the following steps need to be taken.
 143  */
 144 static inline int isp1704_charger_verify(struct isp1704_charger *isp)
 145 {
 146         int     ret = 0;
 147         u8      r;
 148
 149         /* Reset the transceiver */
 150         r = isp1704_read(isp, ULPI_FUNC_CTRL);
 151         r |= ULPI_FUNC_CTRL_RESET;
 152         isp1704_write(isp, ULPI_FUNC_CTRL, r);
 153         usleep_range(1000, 2000);
 154
 155         /* Set normal mode */
 156         r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK);
 157         isp1704_write(isp, ULPI_FUNC_CTRL, r);
 158
 159         /* Clear the DP and DM pull-down bits */
 160         r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN;
 161         isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), r);
 162
 163         /* Enable strong pull-up on DP (1.5K) and reset */
 164         r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
 165         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), r);
 166         usleep_range(1000, 2000);
 167
 168         /* Read the line state */
 169         if (!isp1704_read(isp, ULPI_DEBUG)) {
 170                 /* Disable strong pull-up on DP (1.5K) */
 171                 isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
 172                                 ULPI_FUNC_CTRL_TERMSELECT);
 173                 return 1;
 174         }
 175
 176         /* Is it a charger or PS/2 connection */
 177
 178         /* Enable weak pull-up resistor on DP */
 179         isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
 180                         ISP1704_PWR_CTRL_DP_WKPU_EN);
 181
 182         /* Disable strong pull-up on DP (1.5K) */
 183         isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
 184                         ULPI_FUNC_CTRL_TERMSELECT);
 185
 186         /* Enable weak pull-down resistor on DM */
 187         isp1704_write(isp, ULPI_SET(ULPI_OTG_CTRL),
 188                         ULPI_OTG_CTRL_DM_PULLDOWN);
 189
 190         /* It's a charger if the line states are clear */
 191         if (!(isp1704_read(isp, ULPI_DEBUG)))
 192                 ret = 1;
 193
 194         /* Disable weak pull-up resistor on DP */
 195         isp1704_write(isp, ULPI_CLR(ISP1704_PWR_CTRL),
 196                         ISP1704_PWR_CTRL_DP_WKPU_EN);
 197
 198         return ret;
 199 }
 200
 201 static inline int isp1704_charger_detect(struct isp1704_charger *isp)
 202 {
 203         unsigned long   timeout;
 204         u8              pwr_ctrl;
 205         int             ret = 0;
 206
 207         pwr_ctrl = isp1704_read(isp, ISP1704_PWR_CTRL);
 208
 209         /* set SW control bit in PWR_CTRL register */
 210         isp1704_write(isp, ISP1704_PWR_CTRL,
 211                         ISP1704_PWR_CTRL_SWCTRL);
 212
 213         /* enable manual charger detection */
 214         isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
 215                         ISP1704_PWR_CTRL_SWCTRL
 216                         | ISP1704_PWR_CTRL_DPVSRC_EN);
 217         usleep_range(1000, 2000);
 218
 219         timeout = jiffies + msecs_to_jiffies(300);
 220         do {
 221                 /* Check if there is a charger */
 222                 if (isp1704_read(isp, ISP1704_PWR_CTRL)
 223                                 & ISP1704_PWR_CTRL_VDAT_DET) {
 224                         ret = isp1704_charger_verify(isp);
 225                         break;
 226                 }
 227         } while (!time_after(jiffies, timeout) && isp->online);
 228
 229         /* recover original state */
 230         isp1704_write(isp, ISP1704_PWR_CTRL, pwr_ctrl);
 231
 232         return ret;
 233 }
 234
 235 static inline int isp1704_charger_detect_dcp(struct isp1704_charger *isp)
 236 {
 237         if (isp1704_charger_detect(isp) &&
 238                         isp1704_charger_type(isp) == POWER_SUPPLY_TYPE_USB_DCP)
 239                 return true;
 240         else
 241                 return false;
 242 }
 243
 244 static void isp1704_charger_work(struct work_struct *data)
 245 {
 246         struct isp1704_charger  *isp =
 247                 container_of(data, struct isp1704_charger, work);
 248         static DEFINE_MUTEX(lock);
 249
 250         mutex_lock(&lock);
 251
 252         switch (isp->phy->last_event) {
 253         case USB_EVENT_VBUS:
 254                 /* do not call wall charger detection more times */
 255                 if (!isp->present) {
 256                         isp->online = true;
 257                         isp->present = 1;
 258                         isp1704_charger_set_power(isp, 1);
 259
 260                         /* detect wall charger */
 261                         if (isp1704_charger_detect_dcp(isp)) {
 262                                 isp->psy.type = POWER_SUPPLY_TYPE_USB_DCP;
 263                                 isp->current_max = 1800;
 264                         } else {
 265                                 isp->psy.type = POWER_SUPPLY_TYPE_USB;
 266                                 isp->current_max = 500;
 267                         }
 268
 269                         /* enable data pullups */
 270                         if (isp->phy->otg->gadget)
 271                                 usb_gadget_connect(isp->phy->otg->gadget);
 272                 }
 273
 274                 if (isp->psy.type != POWER_SUPPLY_TYPE_USB_DCP) {
 275                         /*
 276                          * Only 500mA here or high speed chirp
 277                          * handshaking may break
 278                          */
 279                         if (isp->current_max > 500)
 280                                 isp->current_max = 500;
 281
 282                         if (isp->current_max > 100)
 283                                 isp->psy.type = POWER_SUPPLY_TYPE_USB_CDP;
 284                 }
 285                 break;
 286         case USB_EVENT_NONE:
 287                 isp->online = false;
 288                 isp->present = 0;
 289                 isp->current_max = 0;
 290                 isp->psy.type = POWER_SUPPLY_TYPE_USB;
 291
 292                 /*
 293                  * Disable data pullups. We need to prevent the controller from
 294                  * enumerating.
 295                  *
 296                  * FIXME: This is here to allow charger detection with Host/HUB
 297                  * chargers. The pullups may be enabled elsewhere, so this can
 298                  * not be the final solution.
 299                  */
 300                 if (isp->phy->otg->gadget)
 301                         usb_gadget_disconnect(isp->phy->otg->gadget);
 302
 303                 isp1704_charger_set_power(isp, 0);
 304                 break;
 305         default:
 306                 goto out;
 307         }
 308
 309         power_supply_changed(&isp->psy);
 310 out:
 311         mutex_unlock(&lock);
 312 }
 313
 314 static int isp1704_notifier_call(struct notifier_block *nb,
 315                 unsigned long val, void *v)
 316 {
 317         struct isp1704_charger *isp =
 318                 container_of(nb, struct isp1704_charger, nb);
 319
 320         schedule_work(&isp->work);
 321
 322         return NOTIFY_OK;
 323 }
 324
 325 static int isp1704_charger_get_property(struct power_supply *psy,
 326                                 enum power_supply_property psp,
 327                                 union power_supply_propval *val)
 328 {
 329         struct isp1704_charger *isp =
 330                 container_of(psy, struct isp1704_charger, 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
 407         struct isp1704_charger_data *pdata = dev_get_platdata(&pdev->dev);
 408         struct device_node *np = pdev->dev.of_node;
 409
 410         if (np) {
 411                 int gpio = of_get_named_gpio(np, "nxp,enable-gpio", 0);
 412
 413                 if (gpio < 0)
 414                         return gpio;
 415
 416                 pdata = devm_kzalloc(&pdev->dev,
 417                         sizeof(struct isp1704_charger_data), GFP_KERNEL);
 418                 pdata->enable_gpio = gpio;
 419
 420                 dev_info(&pdev->dev, "init gpio %d\n", pdata->enable_gpio);
 421
 422                 ret = devm_gpio_request_one(&pdev->dev, pdata->enable_gpio,
 423                                         GPIOF_OUT_INIT_HIGH, "isp1704_reset");
 424                 if (ret)
 425                         goto fail0;
 426         }
 427
 428         if (!pdata) {
 429                 dev_err(&pdev->dev, "missing platform data!\n");
 430                 return -ENODEV;
 431         }
 432
 433
 434         isp = devm_kzalloc(&pdev->dev, sizeof(*isp), GFP_KERNEL);
 435         if (!isp)
 436                 return -ENOMEM;
 437
 438         if (np)
 439                 isp->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "usb-phy", 0);
 440         else
 441                 isp->phy = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
 442
 443         if (IS_ERR(isp->phy)) {
 444                 ret = PTR_ERR(isp->phy);
 445                 goto fail0;
 446         }
 447         if (!isp->phy)
 448                 goto fail0;
 449
 450         isp->dev = &pdev->dev;
 451         platform_set_drvdata(pdev, isp);
 452
 453         isp1704_charger_set_power(isp, 1);
 454
 455         ret = isp1704_test_ulpi(isp);
 456         if (ret < 0)
 457                 goto fail1;
 458
 459         isp->psy.name           = "isp1704";
 460         isp->psy.type           = POWER_SUPPLY_TYPE_USB;
 461         isp->psy.properties     = power_props;
 462         isp->psy.num_properties = ARRAY_SIZE(power_props);
 463         isp->psy.get_property   = isp1704_charger_get_property;
 464
 465         ret = power_supply_register(isp->dev, &isp->psy);
 466         if (ret)
 467                 goto fail1;
 468
 469         /*
 470          * REVISIT: using work in order to allow the usb notifications to be
 471          * made atomically in the future.
 472          */
 473         INIT_WORK(&isp->work, isp1704_charger_work);
 474
 475         isp->nb.notifier_call = isp1704_notifier_call;
 476
 477         ret = usb_register_notifier(isp->phy, &isp->nb);
 478         if (ret)
 479                 goto fail2;
 480
 481         dev_info(isp->dev, "registered with product id %s\n", isp->model);
 482
 483         /*
 484          * Taking over the D+ pullup.
 485          *
 486          * FIXME: The device will be disconnected if it was already
 487          * enumerated. The charger driver should be always loaded before any
 488          * gadget is loaded.
 489          */
 490         if (isp->phy->otg->gadget)
 491                 usb_gadget_disconnect(isp->phy->otg->gadget);
 492
 493         if (isp->phy->last_event == USB_EVENT_NONE)
 494                 isp1704_charger_set_power(isp, 0);
 495
 496         /* Detect charger if VBUS is valid (the cable was already plugged). */
 497         if (isp->phy->last_event == USB_EVENT_VBUS &&
 498                         !isp->phy->otg->default_a)
 499                 schedule_work(&isp->work);
 500
 501         return 0;
 502 fail2:
 503         power_supply_unregister(&isp->psy);
 504 fail1:
 505         isp1704_charger_set_power(isp, 0);
 506 fail0:
 507         dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret);
 508
 509         return ret;
 510 }
 511
 512 static int isp1704_charger_remove(struct platform_device *pdev)
 513 {
 514         struct isp1704_charger *isp = platform_get_drvdata(pdev);
 515
 516         usb_unregister_notifier(isp->phy, &isp->nb);
 517         power_supply_unregister(&isp->psy);
 518         isp1704_charger_set_power(isp, 0);
 519
 520         return 0;
 521 }
 522
 523 #ifdef CONFIG_OF
 524 static const struct of_device_id omap_isp1704_of_match[] = {
 525         { .compatible = "nxp,isp1704", },
 526         {},
 527 };
 528 MODULE_DEVICE_TABLE(of, omap_isp1704_of_match);
 529 #endif
 530
 531 static struct platform_driver isp1704_charger_driver = {
 532         .driver = {
 533                 .name = "isp1704_charger",
 534                 .of_match_table = of_match_ptr(omap_isp1704_of_match),
 535         },
 536         .probe = isp1704_charger_probe,
 537         .remove = isp1704_charger_remove,
 538 };
 539
 540 module_platform_driver(isp1704_charger_driver);
 541
 542 MODULE_ALIAS("platform:isp1704_charger");
 543 MODULE_AUTHOR("Nokia Corporation");
 544 MODULE_DESCRIPTION("ISP170x USB Charger driver");
 545 MODULE_LICENSE("GPL");