LXR linux/drivers/power/isp1704

   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
  54static u16 isp170x_id[] = {
  55        0x1704,
  56        0x1707,
  57};
  58
  59struct 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
  73static inline int isp1704_read(struct isp1704_charger *isp, u32 reg)
  74{
  75        return usb_phy_io_read(isp->phy, reg);
  76}
  77
  78static 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 */
  87static 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 */
 104static 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 */
 144static 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
 201static 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
 235static 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
 244static 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);
 310out:
 311        mutex_unlock(&lock);
 312}
 313
 314static 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
 325static 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
 354static 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
 362static 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
 402static 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
 448        isp->dev = &pdev->dev;
 449        platform_set_drvdata(pdev, isp);
 450
 451        isp1704_charger_set_power(isp, 1);
 452
 453        ret = isp1704_test_ulpi(isp);
 454        if (ret < 0)
 455                goto fail1;
 456
 457        isp->psy.name           = "isp1704";
 458        isp->psy.type           = POWER_SUPPLY_TYPE_USB;
 459        isp->psy.properties     = power_props;
 460        isp->psy.num_properties = ARRAY_SIZE(power_props);
 461        isp->psy.get_property   = isp1704_charger_get_property;
 462
 463        ret = power_supply_register(isp->dev, &isp->psy);
 464        if (ret)
 465                goto fail1;
 466
 467        /*
 468         * REVISIT: using work in order to allow the usb notifications to be
 469         * made atomically in the future.
 470         */
 471        INIT_WORK(&isp->work, isp1704_charger_work);
 472
 473        isp->nb.notifier_call = isp1704_notifier_call;
 474
 475        ret = usb_register_notifier(isp->phy, &isp->nb);
 476        if (ret)
 477                goto fail2;
 478
 479        dev_info(isp->dev, "registered with product id %s\n", isp->model);
 480
 481        /*
 482         * Taking over the D+ pullup.
 483         *
 484         * FIXME: The device will be disconnected if it was already
 485         * enumerated. The charger driver should be always loaded before any
 486         * gadget is loaded.
 487         */
 488        if (isp->phy->otg->gadget)
 489                usb_gadget_disconnect(isp->phy->otg->gadget);
 490
 491        if (isp->phy->last_event == USB_EVENT_NONE)
 492                isp1704_charger_set_power(isp, 0);
 493
 494        /* Detect charger if VBUS is valid (the cable was already plugged). */
 495        if (isp->phy->last_event == USB_EVENT_VBUS &&
 496                        !isp->phy->otg->default_a)
 497                schedule_work(&isp->work);
 498
 499        return 0;
 500fail2:
 501        power_supply_unregister(&isp->psy);
 502fail1:
 503        isp1704_charger_set_power(isp, 0);
 504fail0:
 505        dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret);
 506
 507        return ret;
 508}
 509
 510static int isp1704_charger_remove(struct platform_device *pdev)
 511{
 512        struct isp1704_charger *isp = platform_get_drvdata(pdev);
 513
 514        usb_unregister_notifier(isp->phy, &isp->nb);
 515        power_supply_unregister(&isp->psy);
 516        isp1704_charger_set_power(isp, 0);
 517
 518        return 0;
 519}
 520
 521#ifdef CONFIG_OF
 522static const struct of_device_id omap_isp1704_of_match[] = {
 523        { .compatible = "nxp,isp1704", },
 524        {},
 525};
 526MODULE_DEVICE_TABLE(of, omap_isp1704_of_match);
 527#endif
 528
 529static struct platform_driver isp1704_charger_driver = {
 530        .driver = {
 531                .name = "isp1704_charger",
 532                .of_match_table = of_match_ptr(omap_isp1704_of_match),
 533        },
 534        .probe = isp1704_charger_probe,
 535        .remove = isp1704_charger_remove,
 536};
 537
 538module_platform_driver(isp1704_charger_driver);
 539
 540MODULE_ALIAS("platform:isp1704_charger");
 541MODULE_AUTHOR("Nokia Corporation");
 542MODULE_DESCRIPTION("ISP170x USB Charger driver");
 543MODULE_LICENSE("GPL");
 544