power/supply/cros_usbpd-charger.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Power supply driver for ChromeOS EC based USB PD Charger.
   4  *
   5  * Copyright (c) 2014 - 2018 Google, Inc
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/mfd/cros_ec.h>
  10 #include <linux/mfd/cros_ec_commands.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/power_supply.h>
  13 #include <linux/slab.h>
  14
  15 #define CHARGER_DIR_NAME                        "CROS_USBPD_CHARGER%d"
  16 #define CHARGER_DIR_NAME_LENGTH                 sizeof(CHARGER_DIR_NAME)
  17 #define CHARGER_CACHE_UPDATE_DELAY              msecs_to_jiffies(500)
  18 #define CHARGER_MANUFACTURER_MODEL_LENGTH       32
  19
  20 #define DRV_NAME "cros-usbpd-charger"
  21
  22 struct port_data {
  23         int port_number;
  24         char name[CHARGER_DIR_NAME_LENGTH];
  25         char manufacturer[CHARGER_MANUFACTURER_MODEL_LENGTH];
  26         char model_name[CHARGER_MANUFACTURER_MODEL_LENGTH];
  27         struct power_supply *psy;
  28         struct power_supply_desc psy_desc;
  29         int psy_usb_type;
  30         int psy_online;
  31         int psy_status;
  32         int psy_current_max;
  33         int psy_voltage_max_design;
  34         int psy_voltage_now;
  35         int psy_power_max;
  36         struct charger_data *charger;
  37         unsigned long last_update;
  38 };
  39
  40 struct charger_data {
  41         struct device *dev;
  42         struct cros_ec_dev *ec_dev;
  43         struct cros_ec_device *ec_device;
  44         int num_charger_ports;
  45         int num_registered_psy;
  46         struct port_data *ports[EC_USB_PD_MAX_PORTS];
  47         struct notifier_block notifier;
  48 };
  49
  50 static enum power_supply_property cros_usbpd_charger_props[] = {
  51         POWER_SUPPLY_PROP_ONLINE,
  52         POWER_SUPPLY_PROP_STATUS,
  53         POWER_SUPPLY_PROP_CURRENT_MAX,
  54         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
  55         POWER_SUPPLY_PROP_VOLTAGE_NOW,
  56         POWER_SUPPLY_PROP_MODEL_NAME,
  57         POWER_SUPPLY_PROP_MANUFACTURER,
  58         POWER_SUPPLY_PROP_USB_TYPE
  59 };
  60
  61 static enum power_supply_usb_type cros_usbpd_charger_usb_types[] = {
  62         POWER_SUPPLY_USB_TYPE_UNKNOWN,
  63         POWER_SUPPLY_USB_TYPE_SDP,
  64         POWER_SUPPLY_USB_TYPE_DCP,
  65         POWER_SUPPLY_USB_TYPE_CDP,
  66         POWER_SUPPLY_USB_TYPE_C,
  67         POWER_SUPPLY_USB_TYPE_PD,
  68         POWER_SUPPLY_USB_TYPE_PD_DRP,
  69         POWER_SUPPLY_USB_TYPE_APPLE_BRICK_ID
  70 };
  71
  72 static int cros_usbpd_charger_ec_command(struct charger_data *charger,
  73                                          unsigned int version,
  74                                          unsigned int command,
  75                                          void *outdata,
  76                                          unsigned int outsize,
  77                                          void *indata,
  78                                          unsigned int insize)
  79 {
  80         struct cros_ec_dev *ec_dev = charger->ec_dev;
  81         struct cros_ec_command *msg;
  82         int ret;
  83
  84         msg = kzalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL);
  85         if (!msg)
  86                 return -ENOMEM;
  87
  88         msg->version = version;
  89         msg->command = ec_dev->cmd_offset + command;
  90         msg->outsize = outsize;
  91         msg->insize = insize;
  92
  93         if (outsize)
  94                 memcpy(msg->data, outdata, outsize);
  95
  96         ret = cros_ec_cmd_xfer_status(charger->ec_device, msg);
  97         if (ret >= 0 && insize)
  98                 memcpy(indata, msg->data, insize);
  99
 100         kfree(msg);
 101         return ret;
 102 }
 103
 104 static int cros_usbpd_charger_get_num_ports(struct charger_data *charger)
 105 {
 106         struct ec_response_usb_pd_ports resp;
 107         int ret;
 108
 109         ret = cros_usbpd_charger_ec_command(charger, 0, EC_CMD_USB_PD_PORTS,
 110                                             NULL, 0, &resp, sizeof(resp));
 111         if (ret < 0) {
 112                 dev_err(charger->dev,
 113                         "Unable to get the number or ports (err:0x%x)\n", ret);
 114                 return ret;
 115         }
 116
 117         return resp.num_ports;
 118 }
 119
 120 static int cros_usbpd_charger_get_discovery_info(struct port_data *port)
 121 {
 122         struct charger_data *charger = port->charger;
 123         struct ec_params_usb_pd_discovery_entry resp;
 124         struct ec_params_usb_pd_info_request req;
 125         int ret;
 126
 127         req.port = port->port_number;
 128
 129         ret = cros_usbpd_charger_ec_command(charger, 0,
 130                                             EC_CMD_USB_PD_DISCOVERY,
 131                                             &req, sizeof(req),
 132                                             &resp, sizeof(resp));
 133         if (ret < 0) {
 134                 dev_err(charger->dev,
 135                         "Unable to query discovery info (err:0x%x)\n", ret);
 136                 return ret;
 137         }
 138
 139         dev_dbg(charger->dev, "Port %d: VID = 0x%x, PID=0x%x, PTYPE=0x%x\n",
 140                 port->port_number, resp.vid, resp.pid, resp.ptype);
 141
 142         snprintf(port->manufacturer, sizeof(port->manufacturer), "%x",
 143                  resp.vid);
 144         snprintf(port->model_name, sizeof(port->model_name), "%x", resp.pid);
 145
 146         return 0;
 147 }
 148
 149 static int cros_usbpd_charger_get_power_info(struct port_data *port)
 150 {
 151         struct charger_data *charger = port->charger;
 152         struct ec_response_usb_pd_power_info resp;
 153         struct ec_params_usb_pd_power_info req;
 154         int last_psy_status, last_psy_usb_type;
 155         struct device *dev = charger->dev;
 156         int ret;
 157
 158         req.port = port->port_number;
 159         ret = cros_usbpd_charger_ec_command(charger, 0,
 160                                             EC_CMD_USB_PD_POWER_INFO,
 161                                             &req, sizeof(req),
 162                                             &resp, sizeof(resp));
 163         if (ret < 0) {
 164                 dev_err(dev, "Unable to query PD power info (err:0x%x)\n", ret);
 165                 return ret;
 166         }
 167
 168         last_psy_status = port->psy_status;
 169         last_psy_usb_type = port->psy_usb_type;
 170
 171         switch (resp.role) {
 172         case USB_PD_PORT_POWER_DISCONNECTED:
 173                 port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 174                 port->psy_online = 0;
 175                 break;
 176         case USB_PD_PORT_POWER_SOURCE:
 177                 port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 178                 port->psy_online = 0;
 179                 break;
 180         case USB_PD_PORT_POWER_SINK:
 181                 port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
 182                 port->psy_online = 1;
 183                 break;
 184         case USB_PD_PORT_POWER_SINK_NOT_CHARGING:
 185                 port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 186                 port->psy_online = 1;
 187                 break;
 188         default:
 189                 dev_err(dev, "Unknown role %d\n", resp.role);
 190                 break;
 191         }
 192
 193         port->psy_voltage_max_design = resp.meas.voltage_max;
 194         port->psy_voltage_now = resp.meas.voltage_now;
 195         port->psy_current_max = resp.meas.current_max;
 196         port->psy_power_max = resp.max_power;
 197
 198         switch (resp.type) {
 199         case USB_CHG_TYPE_BC12_SDP:
 200         case USB_CHG_TYPE_VBUS:
 201                 port->psy_usb_type = POWER_SUPPLY_USB_TYPE_SDP;
 202                 break;
 203         case USB_CHG_TYPE_NONE:
 204                 /*
 205                  * For dual-role devices when we are a source, the firmware
 206                  * reports the type as NONE. Report such chargers as type
 207                  * USB_PD_DRP.
 208                  */
 209                 if (resp.role == USB_PD_PORT_POWER_SOURCE && resp.dualrole)
 210                         port->psy_usb_type = POWER_SUPPLY_USB_TYPE_PD_DRP;
 211                 else
 212                         port->psy_usb_type = POWER_SUPPLY_USB_TYPE_SDP;
 213                 break;
 214         case USB_CHG_TYPE_OTHER:
 215         case USB_CHG_TYPE_PROPRIETARY:
 216                 port->psy_usb_type = POWER_SUPPLY_USB_TYPE_APPLE_BRICK_ID;
 217                 break;
 218         case USB_CHG_TYPE_C:
 219                 port->psy_usb_type = POWER_SUPPLY_USB_TYPE_C;
 220                 break;
 221         case USB_CHG_TYPE_BC12_DCP:
 222                 port->psy_usb_type = POWER_SUPPLY_USB_TYPE_DCP;
 223                 break;
 224         case USB_CHG_TYPE_BC12_CDP:
 225                 port->psy_usb_type = POWER_SUPPLY_USB_TYPE_CDP;
 226                 break;
 227         case USB_CHG_TYPE_PD:
 228                 if (resp.dualrole)
 229                         port->psy_usb_type = POWER_SUPPLY_USB_TYPE_PD_DRP;
 230                 else
 231                         port->psy_usb_type = POWER_SUPPLY_USB_TYPE_PD;
 232                 break;
 233         case USB_CHG_TYPE_UNKNOWN:
 234                 /*
 235                  * While the EC is trying to determine the type of charger that
 236                  * has been plugged in, it will report the charger type as
 237                  * unknown. Additionally since the power capabilities are
 238                  * unknown, report the max current and voltage as zero.
 239                  */
 240                 port->psy_usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;
 241                 port->psy_voltage_max_design = 0;
 242                 port->psy_current_max = 0;
 243                 break;
 244         default:
 245                 dev_err(dev, "Port %d: default case!\n", port->port_number);
 246                 port->psy_usb_type = POWER_SUPPLY_USB_TYPE_SDP;
 247         }
 248
 249         port->psy_desc.type = POWER_SUPPLY_TYPE_USB;
 250
 251         dev_dbg(dev,
 252                 "Port %d: type=%d vmax=%d vnow=%d cmax=%d clim=%d pmax=%d\n",
 253                 port->port_number, resp.type, resp.meas.voltage_max,
 254                 resp.meas.voltage_now, resp.meas.current_max,
 255                 resp.meas.current_lim, resp.max_power);
 256
 257         /*
 258          * If power supply type or status changed, explicitly call
 259          * power_supply_changed. This results in udev event getting generated
 260          * and allows user mode apps to react quicker instead of waiting for
 261          * their next poll of power supply status.
 262          */
 263         if (last_psy_usb_type != port->psy_usb_type ||
 264             last_psy_status != port->psy_status)
 265                 power_supply_changed(port->psy);
 266
 267         return 0;
 268 }
 269
 270 static int cros_usbpd_charger_get_port_status(struct port_data *port,
 271                                               bool ratelimit)
 272 {
 273         int ret;
 274
 275         if (ratelimit &&
 276             time_is_after_jiffies(port->last_update +
 277                                   CHARGER_CACHE_UPDATE_DELAY))
 278                 return 0;
 279
 280         ret = cros_usbpd_charger_get_power_info(port);
 281         if (ret < 0)
 282                 return ret;
 283
 284         ret = cros_usbpd_charger_get_discovery_info(port);
 285         port->last_update = jiffies;
 286
 287         return ret;
 288 }
 289
 290 static void cros_usbpd_charger_power_changed(struct power_supply *psy)
 291 {
 292         struct port_data *port = power_supply_get_drvdata(psy);
 293         struct charger_data *charger = port->charger;
 294         int i;
 295
 296         for (i = 0; i < charger->num_registered_psy; i++)
 297                 cros_usbpd_charger_get_port_status(charger->ports[i], false);
 298 }
 299
 300 static int cros_usbpd_charger_get_prop(struct power_supply *psy,
 301                                        enum power_supply_property psp,
 302                                        union power_supply_propval *val)
 303 {
 304         struct port_data *port = power_supply_get_drvdata(psy);
 305         struct charger_data *charger = port->charger;
 306         struct cros_ec_device *ec_device = charger->ec_device;
 307         struct device *dev = charger->dev;
 308         int ret;
 309
 310         /* Only refresh ec_port_status for dynamic properties */
 311         switch (psp) {
 312         case POWER_SUPPLY_PROP_ONLINE:
 313                 /*
 314                  * If mkbp_event_supported, then we can be assured that
 315                  * the driver's state for the online property is consistent
 316                  * with the hardware. However, if we aren't event driven,
 317                  * the optimization before to skip an ec_port_status get
 318                  * and only returned cached values of the online property will
 319                  * cause a delay in detecting a cable attach until one of the
 320                  * other properties are read.
 321                  *
 322                  * Allow an ec_port_status refresh for online property check
 323                  * if we're not already online to check for plug events if
 324                  * not mkbp_event_supported.
 325                  */
 326                 if (ec_device->mkbp_event_supported || port->psy_online)
 327                         break;
 328                 /* fall through */
 329         case POWER_SUPPLY_PROP_CURRENT_MAX:
 330         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 331         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 332                 ret = cros_usbpd_charger_get_port_status(port, true);
 333                 if (ret < 0) {
 334                         dev_err(dev, "Failed to get port status (err:0x%x)\n",
 335                                 ret);
 336                         return -EINVAL;
 337                 }
 338                 break;
 339         default:
 340                 break;
 341         }
 342
 343         switch (psp) {
 344         case POWER_SUPPLY_PROP_ONLINE:
 345                 val->intval = port->psy_online;
 346                 break;
 347         case POWER_SUPPLY_PROP_STATUS:
 348                 val->intval = port->psy_status;
 349                 break;
 350         case POWER_SUPPLY_PROP_CURRENT_MAX:
 351                 val->intval = port->psy_current_max * 1000;
 352                 break;
 353         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 354                 val->intval = port->psy_voltage_max_design * 1000;
 355                 break;
 356         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 357                 val->intval = port->psy_voltage_now * 1000;
 358                 break;
 359         case POWER_SUPPLY_PROP_USB_TYPE:
 360                 val->intval = port->psy_usb_type;
 361                 break;
 362         case POWER_SUPPLY_PROP_MODEL_NAME:
 363                 val->strval = port->model_name;
 364                 break;
 365         case POWER_SUPPLY_PROP_MANUFACTURER:
 366                 val->strval = port->manufacturer;
 367                 break;
 368         default:
 369                 return -EINVAL;
 370         }
 371
 372         return 0;
 373 }
 374
 375 static int cros_usbpd_charger_ec_event(struct notifier_block *nb,
 376                                        unsigned long queued_during_suspend,
 377                                        void *_notify)
 378 {
 379         struct cros_ec_device *ec_device;
 380         struct charger_data *charger;
 381         struct device *dev;
 382         u32 host_event;
 383
 384         charger = container_of(nb, struct charger_data, notifier);
 385         ec_device = charger->ec_device;
 386         dev = charger->dev;
 387
 388         host_event = cros_ec_get_host_event(ec_device);
 389         if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
 390                 cros_usbpd_charger_power_changed(charger->ports[0]->psy);
 391                 return NOTIFY_OK;
 392         } else {
 393                 return NOTIFY_DONE;
 394         }
 395 }
 396
 397 static void cros_usbpd_charger_unregister_notifier(void *data)
 398 {
 399         struct charger_data *charger = data;
 400         struct cros_ec_device *ec_device = charger->ec_device;
 401
 402         blocking_notifier_chain_unregister(&ec_device->event_notifier,
 403                                            &charger->notifier);
 404 }
 405
 406 static int cros_usbpd_charger_probe(struct platform_device *pd)
 407 {
 408         struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
 409         struct cros_ec_device *ec_device = ec_dev->ec_dev;
 410         struct power_supply_desc *psy_desc;
 411         struct device *dev = &pd->dev;
 412         struct charger_data *charger;
 413         struct power_supply *psy;
 414         struct port_data *port;
 415         int ret = -EINVAL;
 416         int i;
 417
 418         charger = devm_kzalloc(dev, sizeof(struct charger_data),
 419                                GFP_KERNEL);
 420         if (!charger)
 421                 return -ENOMEM;
 422
 423         charger->dev = dev;
 424         charger->ec_dev = ec_dev;
 425         charger->ec_device = ec_device;
 426
 427         platform_set_drvdata(pd, charger);
 428
 429         charger->num_charger_ports = cros_usbpd_charger_get_num_ports(charger);
 430         if (charger->num_charger_ports <= 0) {
 431                 /*
 432                  * This can happen on a system that doesn't support USB PD.
 433                  * Log a message, but no need to warn.
 434                  */
 435                 dev_info(dev, "No charging ports found\n");
 436                 ret = -ENODEV;
 437                 goto fail_nowarn;
 438         }
 439
 440         for (i = 0; i < charger->num_charger_ports; i++) {
 441                 struct power_supply_config psy_cfg = {};
 442
 443                 port = devm_kzalloc(dev, sizeof(struct port_data), GFP_KERNEL);
 444                 if (!port) {
 445                         ret = -ENOMEM;
 446                         goto fail;
 447                 }
 448
 449                 port->charger = charger;
 450                 port->port_number = i;
 451                 sprintf(port->name, CHARGER_DIR_NAME, i);
 452
 453                 psy_desc = &port->psy_desc;
 454                 psy_desc->name = port->name;
 455                 psy_desc->type = POWER_SUPPLY_TYPE_USB;
 456                 psy_desc->get_property = cros_usbpd_charger_get_prop;
 457                 psy_desc->external_power_changed =
 458                                         cros_usbpd_charger_power_changed;
 459                 psy_desc->properties = cros_usbpd_charger_props;
 460                 psy_desc->num_properties =
 461                                         ARRAY_SIZE(cros_usbpd_charger_props);
 462                 psy_desc->usb_types = cros_usbpd_charger_usb_types;
 463                 psy_desc->num_usb_types =
 464                                 ARRAY_SIZE(cros_usbpd_charger_usb_types);
 465                 psy_cfg.drv_data = port;
 466
 467                 psy = devm_power_supply_register_no_ws(dev, psy_desc,
 468                                                        &psy_cfg);
 469                 if (IS_ERR(psy)) {
 470                         dev_err(dev, "Failed to register power supply\n");
 471                         continue;
 472                 }
 473                 port->psy = psy;
 474
 475                 charger->ports[charger->num_registered_psy++] = port;
 476         }
 477
 478         if (!charger->num_registered_psy) {
 479                 ret = -ENODEV;
 480                 dev_err(dev, "No power supplies registered\n");
 481                 goto fail;
 482         }
 483
 484         if (ec_device->mkbp_event_supported) {
 485                 /* Get PD events from the EC */
 486                 charger->notifier.notifier_call = cros_usbpd_charger_ec_event;
 487                 ret = blocking_notifier_chain_register(
 488                                                 &ec_device->event_notifier,
 489                                                 &charger->notifier);
 490                 if (ret < 0) {
 491                         dev_warn(dev, "failed to register notifier\n");
 492                 } else {
 493                         ret = devm_add_action_or_reset(dev,
 494                                         cros_usbpd_charger_unregister_notifier,
 495                                         charger);
 496                         if (ret < 0)
 497                                 goto fail;
 498                 }
 499         }
 500
 501         return 0;
 502
 503 fail:
 504         WARN(1, "%s: Failing probe (err:0x%x)\n", dev_name(dev), ret);
 505
 506 fail_nowarn:
 507         dev_info(dev, "Failing probe (err:0x%x)\n", ret);
 508         return ret;
 509 }
 510
 511 #ifdef CONFIG_PM_SLEEP
 512 static int cros_usbpd_charger_resume(struct device *dev)
 513 {
 514         struct charger_data *charger = dev_get_drvdata(dev);
 515         int i;
 516
 517         if (!charger)
 518                 return 0;
 519
 520         for (i = 0; i < charger->num_registered_psy; i++) {
 521                 power_supply_changed(charger->ports[i]->psy);
 522                 charger->ports[i]->last_update =
 523                                 jiffies - CHARGER_CACHE_UPDATE_DELAY;
 524         }
 525
 526         return 0;
 527 }
 528 #endif
 529
 530 static SIMPLE_DEV_PM_OPS(cros_usbpd_charger_pm_ops, NULL,
 531                          cros_usbpd_charger_resume);
 532
 533 static struct platform_driver cros_usbpd_charger_driver = {
 534         .driver = {
 535                 .name = DRV_NAME,
 536                 .pm = &cros_usbpd_charger_pm_ops,
 537         },
 538         .probe = cros_usbpd_charger_probe
 539 };
 540
 541 module_platform_driver(cros_usbpd_charger_driver);
 542
 543 MODULE_LICENSE("GPL");
 544 MODULE_DESCRIPTION("ChromeOS EC USBPD charger");
 545 MODULE_ALIAS("platform:" DRV_NAME);