drivers/usb/typec/ucsi/ucsi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * USB Type-C Connector System Software Interface driver
   4  *
   5  * Copyright (C) 2017, Intel Corporation
   6  * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
   7  */
   8
   9 #include <linux/completion.h>
  10 #include <linux/property.h>
  11 #include <linux/device.h>
  12 #include <linux/module.h>
  13 #include <linux/delay.h>
  14 #include <linux/slab.h>
  15 #include <linux/usb/typec_dp.h>
  16
  17 #include "ucsi.h"
  18 #include "trace.h"
  19
  20 /*
  21  * UCSI_TIMEOUT_MS - PPM communication timeout
  22  *
  23  * Ideally we could use MIN_TIME_TO_RESPOND_WITH_BUSY (which is defined in UCSI
  24  * specification) here as reference, but unfortunately we can't. It is very
  25  * difficult to estimate the time it takes for the system to process the command
  26  * before it is actually passed to the PPM.
  27  */
  28 #define UCSI_TIMEOUT_MS         5000
  29
  30 /*
  31  * UCSI_SWAP_TIMEOUT_MS - Timeout for role swap requests
  32  *
  33  * 5 seconds is close to the time it takes for CapsCounter to reach 0, so even
  34  * if the PPM does not generate Connector Change events before that with
  35  * partners that do not support USB Power Delivery, this should still work.
  36  */
  37 #define UCSI_SWAP_TIMEOUT_MS    5000
  38
  39 static int ucsi_acknowledge_command(struct ucsi *ucsi)
  40 {
  41         u64 ctrl;
  42
  43         ctrl = UCSI_ACK_CC_CI;
  44         ctrl |= UCSI_ACK_COMMAND_COMPLETE;
  45
  46         return ucsi->ops->sync_write(ucsi, UCSI_CONTROL, &ctrl, sizeof(ctrl));
  47 }
  48
  49 static int ucsi_acknowledge_connector_change(struct ucsi *ucsi)
  50 {
  51         u64 ctrl;
  52
  53         ctrl = UCSI_ACK_CC_CI;
  54         ctrl |= UCSI_ACK_CONNECTOR_CHANGE;
  55
  56         return ucsi->ops->sync_write(ucsi, UCSI_CONTROL, &ctrl, sizeof(ctrl));
  57 }
  58
  59 static int ucsi_exec_command(struct ucsi *ucsi, u64 command);
  60
  61 static int ucsi_read_error(struct ucsi *ucsi)
  62 {
  63         u16 error;
  64         int ret;
  65
  66         /* Acknowlege the command that failed */
  67         ret = ucsi_acknowledge_command(ucsi);
  68         if (ret)
  69                 return ret;
  70
  71         ret = ucsi_exec_command(ucsi, UCSI_GET_ERROR_STATUS);
  72         if (ret < 0)
  73                 return ret;
  74
  75         ret = ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, &error, sizeof(error));
  76         if (ret)
  77                 return ret;
  78
  79         switch (error) {
  80         case UCSI_ERROR_INCOMPATIBLE_PARTNER:
  81                 return -EOPNOTSUPP;
  82         case UCSI_ERROR_CC_COMMUNICATION_ERR:
  83                 return -ECOMM;
  84         case UCSI_ERROR_CONTRACT_NEGOTIATION_FAIL:
  85                 return -EPROTO;
  86         case UCSI_ERROR_DEAD_BATTERY:
  87                 dev_warn(ucsi->dev, "Dead battery condition!\n");
  88                 return -EPERM;
  89         case UCSI_ERROR_INVALID_CON_NUM:
  90         case UCSI_ERROR_UNREGONIZED_CMD:
  91         case UCSI_ERROR_INVALID_CMD_ARGUMENT:
  92                 dev_err(ucsi->dev, "possible UCSI driver bug %u\n", error);
  93                 return -EINVAL;
  94         case UCSI_ERROR_OVERCURRENT:
  95                 dev_warn(ucsi->dev, "Overcurrent condition\n");
  96                 break;
  97         case UCSI_ERROR_PARTNER_REJECTED_SWAP:
  98                 dev_warn(ucsi->dev, "Partner rejected swap\n");
  99                 break;
 100         case UCSI_ERROR_HARD_RESET:
 101                 dev_warn(ucsi->dev, "Hard reset occurred\n");
 102                 break;
 103         case UCSI_ERROR_PPM_POLICY_CONFLICT:
 104                 dev_warn(ucsi->dev, "PPM Policy conflict\n");
 105                 break;
 106         case UCSI_ERROR_SWAP_REJECTED:
 107                 dev_warn(ucsi->dev, "Swap rejected\n");
 108                 break;
 109         case UCSI_ERROR_UNDEFINED:
 110         default:
 111                 dev_err(ucsi->dev, "unknown error %u\n", error);
 112                 break;
 113         }
 114
 115         return -EIO;
 116 }
 117
 118 static int ucsi_exec_command(struct ucsi *ucsi, u64 cmd)
 119 {
 120         u32 cci;
 121         int ret;
 122
 123         ret = ucsi->ops->sync_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
 124         if (ret)
 125                 return ret;
 126
 127         ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci));
 128         if (ret)
 129                 return ret;
 130
 131         if (cci & UCSI_CCI_BUSY)
 132                 return -EBUSY;
 133
 134         if (!(cci & UCSI_CCI_COMMAND_COMPLETE))
 135                 return -EIO;
 136
 137         if (cci & UCSI_CCI_NOT_SUPPORTED)
 138                 return -EOPNOTSUPP;
 139
 140         if (cci & UCSI_CCI_ERROR) {
 141                 if (cmd == UCSI_GET_ERROR_STATUS)
 142                         return -EIO;
 143                 return ucsi_read_error(ucsi);
 144         }
 145
 146         return UCSI_CCI_LENGTH(cci);
 147 }
 148
 149 int ucsi_send_command(struct ucsi *ucsi, u64 command,
 150                       void *data, size_t size)
 151 {
 152         u8 length;
 153         int ret;
 154
 155         mutex_lock(&ucsi->ppm_lock);
 156
 157         ret = ucsi_exec_command(ucsi, command);
 158         if (ret < 0)
 159                 goto out;
 160
 161         length = ret;
 162
 163         if (data) {
 164                 ret = ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, data, size);
 165                 if (ret)
 166                         goto out;
 167         }
 168
 169         ret = ucsi_acknowledge_command(ucsi);
 170         if (ret)
 171                 goto out;
 172
 173         ret = length;
 174 out:
 175         mutex_unlock(&ucsi->ppm_lock);
 176         return ret;
 177 }
 178 EXPORT_SYMBOL_GPL(ucsi_send_command);
 179
 180 int ucsi_resume(struct ucsi *ucsi)
 181 {
 182         u64 command;
 183
 184         /* Restore UCSI notification enable mask after system resume */
 185         command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy;
 186
 187         return ucsi_send_command(ucsi, command, NULL, 0);
 188 }
 189 EXPORT_SYMBOL_GPL(ucsi_resume);
 190 /* -------------------------------------------------------------------------- */
 191
 192 void ucsi_altmode_update_active(struct ucsi_connector *con)
 193 {
 194         const struct typec_altmode *altmode = NULL;
 195         u64 command;
 196         int ret;
 197         u8 cur;
 198         int i;
 199
 200         command = UCSI_GET_CURRENT_CAM | UCSI_CONNECTOR_NUMBER(con->num);
 201         ret = ucsi_send_command(con->ucsi, command, &cur, sizeof(cur));
 202         if (ret < 0) {
 203                 if (con->ucsi->version > 0x0100) {
 204                         dev_err(con->ucsi->dev,
 205                                 "GET_CURRENT_CAM command failed\n");
 206                         return;
 207                 }
 208                 cur = 0xff;
 209         }
 210
 211         if (cur < UCSI_MAX_ALTMODES)
 212                 altmode = typec_altmode_get_partner(con->port_altmode[cur]);
 213
 214         for (i = 0; con->partner_altmode[i]; i++)
 215                 typec_altmode_update_active(con->partner_altmode[i],
 216                                             con->partner_altmode[i] == altmode);
 217 }
 218
 219 static int ucsi_altmode_next_mode(struct typec_altmode **alt, u16 svid)
 220 {
 221         u8 mode = 1;
 222         int i;
 223
 224         for (i = 0; alt[i]; i++) {
 225                 if (i > MODE_DISCOVERY_MAX)
 226                         return -ERANGE;
 227
 228                 if (alt[i]->svid == svid)
 229                         mode++;
 230         }
 231
 232         return mode;
 233 }
 234
 235 static int ucsi_next_altmode(struct typec_altmode **alt)
 236 {
 237         int i = 0;
 238
 239         for (i = 0; i < UCSI_MAX_ALTMODES; i++)
 240                 if (!alt[i])
 241                         return i;
 242
 243         return -ENOENT;
 244 }
 245
 246 static int ucsi_register_altmode(struct ucsi_connector *con,
 247                                  struct typec_altmode_desc *desc,
 248                                  u8 recipient)
 249 {
 250         struct typec_altmode *alt;
 251         bool override;
 252         int ret;
 253         int i;
 254
 255         override = !!(con->ucsi->cap.features & UCSI_CAP_ALT_MODE_OVERRIDE);
 256
 257         switch (recipient) {
 258         case UCSI_RECIPIENT_CON:
 259                 i = ucsi_next_altmode(con->port_altmode);
 260                 if (i < 0) {
 261                         ret = i;
 262                         goto err;
 263                 }
 264
 265                 ret = ucsi_altmode_next_mode(con->port_altmode, desc->svid);
 266                 if (ret < 0)
 267                         return ret;
 268
 269                 desc->mode = ret;
 270
 271                 switch (desc->svid) {
 272                 case USB_TYPEC_DP_SID:
 273                         alt = ucsi_register_displayport(con, override, i, desc);
 274                         break;
 275                 case USB_TYPEC_NVIDIA_VLINK_SID:
 276                         if (desc->vdo == USB_TYPEC_NVIDIA_VLINK_DBG_VDO)
 277                                 alt = typec_port_register_altmode(con->port,
 278                                                                   desc);
 279                         else
 280                                 alt = ucsi_register_displayport(con, override,
 281                                                                 i, desc);
 282                         break;
 283                 default:
 284                         alt = typec_port_register_altmode(con->port, desc);
 285                         break;
 286                 }
 287
 288                 if (IS_ERR(alt)) {
 289                         ret = PTR_ERR(alt);
 290                         goto err;
 291                 }
 292
 293                 con->port_altmode[i] = alt;
 294                 break;
 295         case UCSI_RECIPIENT_SOP:
 296                 i = ucsi_next_altmode(con->partner_altmode);
 297                 if (i < 0) {
 298                         ret = i;
 299                         goto err;
 300                 }
 301
 302                 ret = ucsi_altmode_next_mode(con->partner_altmode, desc->svid);
 303                 if (ret < 0)
 304                         return ret;
 305
 306                 desc->mode = ret;
 307
 308                 alt = typec_partner_register_altmode(con->partner, desc);
 309                 if (IS_ERR(alt)) {
 310                         ret = PTR_ERR(alt);
 311                         goto err;
 312                 }
 313
 314                 con->partner_altmode[i] = alt;
 315                 break;
 316         default:
 317                 return -EINVAL;
 318         }
 319
 320         trace_ucsi_register_altmode(recipient, alt);
 321
 322         return 0;
 323
 324 err:
 325         dev_err(con->ucsi->dev, "failed to registers svid 0x%04x mode %d\n",
 326                 desc->svid, desc->mode);
 327
 328         return ret;
 329 }
 330
 331 static int
 332 ucsi_register_altmodes_nvidia(struct ucsi_connector *con, u8 recipient)
 333 {
 334         int max_altmodes = UCSI_MAX_ALTMODES;
 335         struct typec_altmode_desc desc;
 336         struct ucsi_altmode alt;
 337         struct ucsi_altmode orig[UCSI_MAX_ALTMODES];
 338         struct ucsi_altmode updated[UCSI_MAX_ALTMODES];
 339         struct ucsi *ucsi = con->ucsi;
 340         bool multi_dp = false;
 341         u64 command;
 342         int ret;
 343         int len;
 344         int i;
 345         int k = 0;
 346
 347         if (recipient == UCSI_RECIPIENT_CON)
 348                 max_altmodes = con->ucsi->cap.num_alt_modes;
 349
 350         memset(orig, 0, sizeof(orig));
 351         memset(updated, 0, sizeof(updated));
 352
 353         /* First get all the alternate modes */
 354         for (i = 0; i < max_altmodes; i++) {
 355                 memset(&alt, 0, sizeof(alt));
 356                 command = UCSI_GET_ALTERNATE_MODES;
 357                 command |= UCSI_GET_ALTMODE_RECIPIENT(recipient);
 358                 command |= UCSI_GET_ALTMODE_CONNECTOR_NUMBER(con->num);
 359                 command |= UCSI_GET_ALTMODE_OFFSET(i);
 360                 len = ucsi_send_command(con->ucsi, command, &alt, sizeof(alt));
 361                 /*
 362                  * We are collecting all altmodes first and then registering.
 363                  * Some type-C device will return zero length data beyond last
 364                  * alternate modes. We should not return if length is zero.
 365                  */
 366                 if (len < 0)
 367                         return len;
 368
 369                 /* We got all altmodes, now break out and register them */
 370                 if (!len || !alt.svid)
 371                         break;
 372
 373                 orig[k].mid = alt.mid;
 374                 orig[k].svid = alt.svid;
 375                 k++;
 376         }
 377         /*
 378          * Update the original altmode table as some ppms may report
 379          * multiple DP altmodes.
 380          */
 381         if (recipient == UCSI_RECIPIENT_CON)
 382                 multi_dp = ucsi->ops->update_altmodes(ucsi, orig, updated);
 383
 384         /* now register altmodes */
 385         for (i = 0; i < max_altmodes; i++) {
 386                 memset(&desc, 0, sizeof(desc));
 387                 if (multi_dp && recipient == UCSI_RECIPIENT_CON) {
 388                         desc.svid = updated[i].svid;
 389                         desc.vdo = updated[i].mid;
 390                 } else {
 391                         desc.svid = orig[i].svid;
 392                         desc.vdo = orig[i].mid;
 393                 }
 394                 desc.roles = TYPEC_PORT_DRD;
 395
 396                 if (!desc.svid)
 397                         return 0;
 398
 399                 ret = ucsi_register_altmode(con, &desc, recipient);
 400                 if (ret)
 401                         return ret;
 402         }
 403
 404         return 0;
 405 }
 406
 407 static int ucsi_register_altmodes(struct ucsi_connector *con, u8 recipient)
 408 {
 409         int max_altmodes = UCSI_MAX_ALTMODES;
 410         struct typec_altmode_desc desc;
 411         struct ucsi_altmode alt[2];
 412         u64 command;
 413         int num;
 414         int ret;
 415         int len;
 416         int j;
 417         int i;
 418
 419         if (!(con->ucsi->cap.features & UCSI_CAP_ALT_MODE_DETAILS))
 420                 return 0;
 421
 422         if (recipient == UCSI_RECIPIENT_SOP && con->partner_altmode[0])
 423                 return 0;
 424
 425         if (con->ucsi->ops->update_altmodes)
 426                 return ucsi_register_altmodes_nvidia(con, recipient);
 427
 428         if (recipient == UCSI_RECIPIENT_CON)
 429                 max_altmodes = con->ucsi->cap.num_alt_modes;
 430
 431         for (i = 0; i < max_altmodes;) {
 432                 memset(alt, 0, sizeof(alt));
 433                 command = UCSI_GET_ALTERNATE_MODES;
 434                 command |= UCSI_GET_ALTMODE_RECIPIENT(recipient);
 435                 command |= UCSI_GET_ALTMODE_CONNECTOR_NUMBER(con->num);
 436                 command |= UCSI_GET_ALTMODE_OFFSET(i);
 437                 len = ucsi_send_command(con->ucsi, command, alt, sizeof(alt));
 438                 if (len <= 0)
 439                         return len;
 440
 441                 /*
 442                  * This code is requesting one alt mode at a time, but some PPMs
 443                  * may still return two. If that happens both alt modes need be
 444                  * registered and the offset for the next alt mode has to be
 445                  * incremented.
 446                  */
 447                 num = len / sizeof(alt[0]);
 448                 i += num;
 449
 450                 for (j = 0; j < num; j++) {
 451                         if (!alt[j].svid)
 452                                 return 0;
 453
 454                         memset(&desc, 0, sizeof(desc));
 455                         desc.vdo = alt[j].mid;
 456                         desc.svid = alt[j].svid;
 457                         desc.roles = TYPEC_PORT_DRD;
 458
 459                         ret = ucsi_register_altmode(con, &desc, recipient);
 460                         if (ret)
 461                                 return ret;
 462                 }
 463         }
 464
 465         return 0;
 466 }
 467
 468 static void ucsi_unregister_altmodes(struct ucsi_connector *con, u8 recipient)
 469 {
 470         const struct typec_altmode *pdev;
 471         struct typec_altmode **adev;
 472         int i = 0;
 473
 474         switch (recipient) {
 475         case UCSI_RECIPIENT_CON:
 476                 adev = con->port_altmode;
 477                 break;
 478         case UCSI_RECIPIENT_SOP:
 479                 adev = con->partner_altmode;
 480                 break;
 481         default:
 482                 return;
 483         }
 484
 485         while (adev[i]) {
 486                 if (recipient == UCSI_RECIPIENT_SOP &&
 487                     (adev[i]->svid == USB_TYPEC_DP_SID ||
 488                         (adev[i]->svid == USB_TYPEC_NVIDIA_VLINK_SID &&
 489                         adev[i]->vdo != USB_TYPEC_NVIDIA_VLINK_DBG_VDO))) {
 490                         pdev = typec_altmode_get_partner(adev[i]);
 491                         ucsi_displayport_remove_partner((void *)pdev);
 492                 }
 493                 typec_unregister_altmode(adev[i]);
 494                 adev[i++] = NULL;
 495         }
 496 }
 497
 498 static int ucsi_get_pdos(struct ucsi_connector *con, int is_partner,
 499                          u32 *pdos, int offset, int num_pdos)
 500 {
 501         struct ucsi *ucsi = con->ucsi;
 502         u64 command;
 503         int ret;
 504
 505         command = UCSI_COMMAND(UCSI_GET_PDOS) | UCSI_CONNECTOR_NUMBER(con->num);
 506         command |= UCSI_GET_PDOS_PARTNER_PDO(is_partner);
 507         command |= UCSI_GET_PDOS_PDO_OFFSET(offset);
 508         command |= UCSI_GET_PDOS_NUM_PDOS(num_pdos - 1);
 509         command |= UCSI_GET_PDOS_SRC_PDOS;
 510         ret = ucsi_send_command(ucsi, command, pdos + offset,
 511                                 num_pdos * sizeof(u32));
 512         if (ret < 0)
 513                 dev_err(ucsi->dev, "UCSI_GET_PDOS failed (%d)\n", ret);
 514         if (ret == 0 && offset == 0)
 515                 dev_warn(ucsi->dev, "UCSI_GET_PDOS returned 0 bytes\n");
 516
 517         return ret;
 518 }
 519
 520 static void ucsi_get_src_pdos(struct ucsi_connector *con, int is_partner)
 521 {
 522         int ret;
 523
 524         /* UCSI max payload means only getting at most 4 PDOs at a time */
 525         ret = ucsi_get_pdos(con, 1, con->src_pdos, 0, UCSI_MAX_PDOS);
 526         if (ret < 0)
 527                 return;
 528
 529         con->num_pdos = ret / sizeof(u32); /* number of bytes to 32-bit PDOs */
 530         if (con->num_pdos < UCSI_MAX_PDOS)
 531                 return;
 532
 533         /* get the remaining PDOs, if any */
 534         ret = ucsi_get_pdos(con, 1, con->src_pdos, UCSI_MAX_PDOS,
 535                             PDO_MAX_OBJECTS - UCSI_MAX_PDOS);
 536         if (ret < 0)
 537                 return;
 538
 539         con->num_pdos += ret / sizeof(u32);
 540 }
 541
 542 static void ucsi_pwr_opmode_change(struct ucsi_connector *con)
 543 {
 544         switch (UCSI_CONSTAT_PWR_OPMODE(con->status.flags)) {
 545         case UCSI_CONSTAT_PWR_OPMODE_PD:
 546                 con->rdo = con->status.request_data_obj;
 547                 typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_PD);
 548                 ucsi_get_src_pdos(con, 1);
 549                 break;
 550         case UCSI_CONSTAT_PWR_OPMODE_TYPEC1_5:
 551                 con->rdo = 0;
 552                 typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_1_5A);
 553                 break;
 554         case UCSI_CONSTAT_PWR_OPMODE_TYPEC3_0:
 555                 con->rdo = 0;
 556                 typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_3_0A);
 557                 break;
 558         default:
 559                 con->rdo = 0;
 560                 typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_USB);
 561                 break;
 562         }
 563 }
 564
 565 static int ucsi_register_partner(struct ucsi_connector *con)
 566 {
 567         u8 pwr_opmode = UCSI_CONSTAT_PWR_OPMODE(con->status.flags);
 568         struct typec_partner_desc desc;
 569         struct typec_partner *partner;
 570
 571         if (con->partner)
 572                 return 0;
 573
 574         memset(&desc, 0, sizeof(desc));
 575
 576         switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) {
 577         case UCSI_CONSTAT_PARTNER_TYPE_DEBUG:
 578                 desc.accessory = TYPEC_ACCESSORY_DEBUG;
 579                 break;
 580         case UCSI_CONSTAT_PARTNER_TYPE_AUDIO:
 581                 desc.accessory = TYPEC_ACCESSORY_AUDIO;
 582                 break;
 583         default:
 584                 break;
 585         }
 586
 587         desc.usb_pd = pwr_opmode == UCSI_CONSTAT_PWR_OPMODE_PD;
 588
 589         partner = typec_register_partner(con->port, &desc);
 590         if (IS_ERR(partner)) {
 591                 dev_err(con->ucsi->dev,
 592                         "con%d: failed to register partner (%ld)\n", con->num,
 593                         PTR_ERR(partner));
 594                 return PTR_ERR(partner);
 595         }
 596
 597         con->partner = partner;
 598
 599         return 0;
 600 }
 601
 602 static void ucsi_unregister_partner(struct ucsi_connector *con)
 603 {
 604         if (!con->partner)
 605                 return;
 606
 607         ucsi_unregister_altmodes(con, UCSI_RECIPIENT_SOP);
 608         typec_unregister_partner(con->partner);
 609         con->partner = NULL;
 610 }
 611
 612 static void ucsi_partner_change(struct ucsi_connector *con)
 613 {
 614         int ret;
 615
 616         if (!con->partner)
 617                 return;
 618
 619         switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) {
 620         case UCSI_CONSTAT_PARTNER_TYPE_UFP:
 621         case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
 622         case UCSI_CONSTAT_PARTNER_TYPE_CABLE_AND_UFP:
 623                 typec_set_data_role(con->port, TYPEC_HOST);
 624                 break;
 625         case UCSI_CONSTAT_PARTNER_TYPE_DFP:
 626                 typec_set_data_role(con->port, TYPEC_DEVICE);
 627                 break;
 628         default:
 629                 break;
 630         }
 631
 632         /* Complete pending data role swap */
 633         if (!completion_done(&con->complete))
 634                 complete(&con->complete);
 635
 636         /* Can't rely on Partner Flags field. Always checking the alt modes. */
 637         ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_SOP);
 638         if (ret)
 639                 dev_err(con->ucsi->dev,
 640                         "con%d: failed to register partner alternate modes\n",
 641                         con->num);
 642         else
 643                 ucsi_altmode_update_active(con);
 644 }
 645
 646 static void ucsi_handle_connector_change(struct work_struct *work)
 647 {
 648         struct ucsi_connector *con = container_of(work, struct ucsi_connector,
 649                                                   work);
 650         struct ucsi *ucsi = con->ucsi;
 651         struct ucsi_connector_status pre_ack_status;
 652         struct ucsi_connector_status post_ack_status;
 653         enum typec_role role;
 654         u16 inferred_changes;
 655         u16 changed_flags;
 656         u64 command;
 657         int ret;
 658
 659         mutex_lock(&con->lock);
 660
 661         /*
 662          * Some/many PPMs have an issue where all fields in the change bitfield
 663          * are cleared when an ACK is send. This will causes any change
 664          * between GET_CONNECTOR_STATUS and ACK to be lost.
 665          *
 666          * We work around this by re-fetching the connector status afterwards.
 667          * We then infer any changes that we see have happened but that may not
 668          * be represented in the change bitfield.
 669          *
 670          * Also, even though we don't need to know the currently supported alt
 671          * modes, we run the GET_CAM_SUPPORTED command to ensure the PPM does
 672          * not get stuck in case it assumes we do.
 673          * Always do this, rather than relying on UCSI_CONSTAT_CAM_CHANGE to be
 674          * set in the change bitfield.
 675          *
 676          * We end up with the following actions:
 677          *  1. UCSI_GET_CONNECTOR_STATUS, store result, update unprocessed_changes
 678          *  2. UCSI_GET_CAM_SUPPORTED, discard result
 679          *  3. ACK connector change
 680          *  4. UCSI_GET_CONNECTOR_STATUS, store result
 681          *  5. Infere lost changes by comparing UCSI_GET_CONNECTOR_STATUS results
 682          *  6. If PPM reported a new change, then restart in order to ACK
 683          *  7. Process everything as usual.
 684          *
 685          * We may end up seeing a change twice, but we can only miss extremely
 686          * short transitional changes.
 687          */
 688
 689         /* 1. First UCSI_GET_CONNECTOR_STATUS */
 690         command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num);
 691         ret = ucsi_send_command(ucsi, command, &pre_ack_status,
 692                                 sizeof(pre_ack_status));
 693         if (ret < 0) {
 694                 dev_err(ucsi->dev, "%s: GET_CONNECTOR_STATUS failed (%d)\n",
 695                         __func__, ret);
 696                 goto out_unlock;
 697         }
 698         con->unprocessed_changes |= pre_ack_status.change;
 699
 700         /* 2. Run UCSI_GET_CAM_SUPPORTED and discard the result. */
 701         command = UCSI_GET_CAM_SUPPORTED;
 702         command |= UCSI_CONNECTOR_NUMBER(con->num);
 703         ucsi_send_command(con->ucsi, command, NULL, 0);
 704
 705         /* 3. ACK connector change */
 706         clear_bit(EVENT_PENDING, &ucsi->flags);
 707         ret = ucsi_acknowledge_connector_change(ucsi);
 708         if (ret) {
 709                 dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret);
 710                 goto out_unlock;
 711         }
 712
 713         /* 4. Second UCSI_GET_CONNECTOR_STATUS */
 714         command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num);
 715         ret = ucsi_send_command(ucsi, command, &post_ack_status,
 716                                 sizeof(post_ack_status));
 717         if (ret < 0) {
 718                 dev_err(ucsi->dev, "%s: GET_CONNECTOR_STATUS failed (%d)\n",
 719                         __func__, ret);
 720                 goto out_unlock;
 721         }
 722
 723         /* 5. Inferre any missing changes */
 724         changed_flags = pre_ack_status.flags ^ post_ack_status.flags;
 725         inferred_changes = 0;
 726         if (UCSI_CONSTAT_PWR_OPMODE(changed_flags) != 0)
 727                 inferred_changes |= UCSI_CONSTAT_POWER_OPMODE_CHANGE;
 728
 729         if (changed_flags & UCSI_CONSTAT_CONNECTED)
 730                 inferred_changes |= UCSI_CONSTAT_CONNECT_CHANGE;
 731
 732         if (changed_flags & UCSI_CONSTAT_PWR_DIR)
 733                 inferred_changes |= UCSI_CONSTAT_POWER_DIR_CHANGE;
 734
 735         if (UCSI_CONSTAT_PARTNER_FLAGS(changed_flags) != 0)
 736                 inferred_changes |= UCSI_CONSTAT_PARTNER_CHANGE;
 737
 738         if (UCSI_CONSTAT_PARTNER_TYPE(changed_flags) != 0)
 739                 inferred_changes |= UCSI_CONSTAT_PARTNER_CHANGE;
 740
 741         /* Mask out anything that was correctly notified in the later call. */
 742         inferred_changes &= ~post_ack_status.change;
 743         if (inferred_changes)
 744                 dev_dbg(ucsi->dev, "%s: Inferred changes that would have been lost: 0x%04x\n",
 745                         __func__, inferred_changes);
 746
 747         con->unprocessed_changes |= inferred_changes;
 748
 749         /* 6. If PPM reported a new change, then restart in order to ACK */
 750         if (post_ack_status.change)
 751                 goto out_unlock;
 752
 753         /* 7. Continue as if nothing happened */
 754         con->status = post_ack_status;
 755         con->status.change = con->unprocessed_changes;
 756         con->unprocessed_changes = 0;
 757
 758         role = !!(con->status.flags & UCSI_CONSTAT_PWR_DIR);
 759
 760         if (con->status.change & UCSI_CONSTAT_POWER_OPMODE_CHANGE ||
 761             con->status.change & UCSI_CONSTAT_POWER_LEVEL_CHANGE) {
 762                 ucsi_pwr_opmode_change(con);
 763                 ucsi_port_psy_changed(con);
 764         }
 765
 766         if (con->status.change & UCSI_CONSTAT_POWER_DIR_CHANGE) {
 767                 typec_set_pwr_role(con->port, role);
 768
 769                 /* Complete pending power role swap */
 770                 if (!completion_done(&con->complete))
 771                         complete(&con->complete);
 772         }
 773
 774         if (con->status.change & UCSI_CONSTAT_CONNECT_CHANGE) {
 775                 typec_set_pwr_role(con->port, role);
 776
 777                 switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) {
 778                 case UCSI_CONSTAT_PARTNER_TYPE_UFP:
 779                 case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
 780                 case UCSI_CONSTAT_PARTNER_TYPE_CABLE_AND_UFP:
 781                         typec_set_data_role(con->port, TYPEC_HOST);
 782                         break;
 783                 case UCSI_CONSTAT_PARTNER_TYPE_DFP:
 784                         typec_set_data_role(con->port, TYPEC_DEVICE);
 785                         break;
 786                 default:
 787                         break;
 788                 }
 789
 790                 if (con->status.flags & UCSI_CONSTAT_CONNECTED)
 791                         ucsi_register_partner(con);
 792                 else
 793                         ucsi_unregister_partner(con);
 794
 795                 ucsi_port_psy_changed(con);
 796         }
 797
 798         if (con->status.change & UCSI_CONSTAT_PARTNER_CHANGE)
 799                 ucsi_partner_change(con);
 800
 801         trace_ucsi_connector_change(con->num, &con->status);
 802
 803 out_unlock:
 804         if (test_and_clear_bit(EVENT_PENDING, &ucsi->flags)) {
 805                 schedule_work(&con->work);
 806                 mutex_unlock(&con->lock);
 807                 return;
 808         }
 809
 810         clear_bit(EVENT_PROCESSING, &ucsi->flags);
 811         mutex_unlock(&con->lock);
 812 }
 813
 814 /**
 815  * ucsi_connector_change - Process Connector Change Event
 816  * @ucsi: UCSI Interface
 817  * @num: Connector number
 818  */
 819 void ucsi_connector_change(struct ucsi *ucsi, u8 num)
 820 {
 821         struct ucsi_connector *con = &ucsi->connector[num - 1];
 822
 823         if (!(ucsi->ntfy & UCSI_ENABLE_NTFY_CONNECTOR_CHANGE)) {
 824                 dev_dbg(ucsi->dev, "Bogus connector change event\n");
 825                 return;
 826         }
 827
 828         set_bit(EVENT_PENDING, &ucsi->flags);
 829
 830         if (!test_and_set_bit(EVENT_PROCESSING, &ucsi->flags))
 831                 schedule_work(&con->work);
 832 }
 833 EXPORT_SYMBOL_GPL(ucsi_connector_change);
 834
 835 /* -------------------------------------------------------------------------- */
 836
 837 static int ucsi_reset_connector(struct ucsi_connector *con, bool hard)
 838 {
 839         u64 command;
 840
 841         command = UCSI_CONNECTOR_RESET | UCSI_CONNECTOR_NUMBER(con->num);
 842         command |= hard ? UCSI_CONNECTOR_RESET_HARD : 0;
 843
 844         return ucsi_send_command(con->ucsi, command, NULL, 0);
 845 }
 846
 847 static int ucsi_reset_ppm(struct ucsi *ucsi)
 848 {
 849         u64 command = UCSI_PPM_RESET;
 850         unsigned long tmo;
 851         u32 cci;
 852         int ret;
 853
 854         mutex_lock(&ucsi->ppm_lock);
 855
 856         ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL, &command,
 857                                      sizeof(command));
 858         if (ret < 0)
 859                 goto out;
 860
 861         tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS);
 862
 863         do {
 864                 if (time_is_before_jiffies(tmo)) {
 865                         ret = -ETIMEDOUT;
 866                         goto out;
 867                 }
 868
 869                 ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci));
 870                 if (ret)
 871                         goto out;
 872
 873                 /* If the PPM is still doing something else, reset it again. */
 874                 if (cci & ~UCSI_CCI_RESET_COMPLETE) {
 875                         ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL,
 876                                                      &command,
 877                                                      sizeof(command));
 878                         if (ret < 0)
 879                                 goto out;
 880                 }
 881
 882                 msleep(20);
 883         } while (!(cci & UCSI_CCI_RESET_COMPLETE));
 884
 885 out:
 886         mutex_unlock(&ucsi->ppm_lock);
 887         return ret;
 888 }
 889
 890 static int ucsi_role_cmd(struct ucsi_connector *con, u64 command)
 891 {
 892         int ret;
 893
 894         ret = ucsi_send_command(con->ucsi, command, NULL, 0);
 895         if (ret == -ETIMEDOUT) {
 896                 u64 c;
 897
 898                 /* PPM most likely stopped responding. Resetting everything. */
 899                 ucsi_reset_ppm(con->ucsi);
 900
 901                 c = UCSI_SET_NOTIFICATION_ENABLE | con->ucsi->ntfy;
 902                 ucsi_send_command(con->ucsi, c, NULL, 0);
 903
 904                 ucsi_reset_connector(con, true);
 905         }
 906
 907         return ret;
 908 }
 909
 910 static int ucsi_dr_swap(struct typec_port *port, enum typec_data_role role)
 911 {
 912         struct ucsi_connector *con = typec_get_drvdata(port);
 913         u8 partner_type;
 914         u64 command;
 915         int ret = 0;
 916
 917         mutex_lock(&con->lock);
 918
 919         if (!con->partner) {
 920                 ret = -ENOTCONN;
 921                 goto out_unlock;
 922         }
 923
 924         partner_type = UCSI_CONSTAT_PARTNER_TYPE(con->status.flags);
 925         if ((partner_type == UCSI_CONSTAT_PARTNER_TYPE_DFP &&
 926              role == TYPEC_DEVICE) ||
 927             (partner_type == UCSI_CONSTAT_PARTNER_TYPE_UFP &&
 928              role == TYPEC_HOST))
 929                 goto out_unlock;
 930
 931         command = UCSI_SET_UOR | UCSI_CONNECTOR_NUMBER(con->num);
 932         command |= UCSI_SET_UOR_ROLE(role);
 933         command |= UCSI_SET_UOR_ACCEPT_ROLE_SWAPS;
 934         ret = ucsi_role_cmd(con, command);
 935         if (ret < 0)
 936                 goto out_unlock;
 937
 938         if (!wait_for_completion_timeout(&con->complete,
 939                                         msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS)))
 940                 ret = -ETIMEDOUT;
 941
 942 out_unlock:
 943         mutex_unlock(&con->lock);
 944
 945         return ret < 0 ? ret : 0;
 946 }
 947
 948 static int ucsi_pr_swap(struct typec_port *port, enum typec_role role)
 949 {
 950         struct ucsi_connector *con = typec_get_drvdata(port);
 951         enum typec_role cur_role;
 952         u64 command;
 953         int ret = 0;
 954
 955         mutex_lock(&con->lock);
 956
 957         if (!con->partner) {
 958                 ret = -ENOTCONN;
 959                 goto out_unlock;
 960         }
 961
 962         cur_role = !!(con->status.flags & UCSI_CONSTAT_PWR_DIR);
 963
 964         if (cur_role == role)
 965                 goto out_unlock;
 966
 967         command = UCSI_SET_PDR | UCSI_CONNECTOR_NUMBER(con->num);
 968         command |= UCSI_SET_PDR_ROLE(role);
 969         command |= UCSI_SET_PDR_ACCEPT_ROLE_SWAPS;
 970         ret = ucsi_role_cmd(con, command);
 971         if (ret < 0)
 972                 goto out_unlock;
 973
 974         if (!wait_for_completion_timeout(&con->complete,
 975                                 msecs_to_jiffies(UCSI_SWAP_TIMEOUT_MS))) {
 976                 ret = -ETIMEDOUT;
 977                 goto out_unlock;
 978         }
 979
 980         /* Something has gone wrong while swapping the role */
 981         if (UCSI_CONSTAT_PWR_OPMODE(con->status.flags) !=
 982             UCSI_CONSTAT_PWR_OPMODE_PD) {
 983                 ucsi_reset_connector(con, true);
 984                 ret = -EPROTO;
 985         }
 986
 987 out_unlock:
 988         mutex_unlock(&con->lock);
 989
 990         return ret;
 991 }
 992
 993 static const struct typec_operations ucsi_ops = {
 994         .dr_set = ucsi_dr_swap,
 995         .pr_set = ucsi_pr_swap
 996 };
 997
 998 /* Caller must call fwnode_handle_put() after use */
 999 static struct fwnode_handle *ucsi_find_fwnode(struct ucsi_connector *con)
1000 {
1001         struct fwnode_handle *fwnode;
1002         int i = 1;
1003
1004         device_for_each_child_node(con->ucsi->dev, fwnode)
1005                 if (i++ == con->num)
1006                         return fwnode;
1007         return NULL;
1008 }
1009
1010 static int ucsi_register_port(struct ucsi *ucsi, int index)
1011 {
1012         struct ucsi_connector *con = &ucsi->connector[index];
1013         struct typec_capability *cap = &con->typec_cap;
1014         enum typec_accessory *accessory = cap->accessory;
1015         u64 command;
1016         int ret;
1017
1018         INIT_WORK(&con->work, ucsi_handle_connector_change);
1019         init_completion(&con->complete);
1020         mutex_init(&con->lock);
1021         con->num = index + 1;
1022         con->ucsi = ucsi;
1023
1024         /* Delay other interactions with the con until registration is complete */
1025         mutex_lock(&con->lock);
1026
1027         /* Get connector capability */
1028         command = UCSI_GET_CONNECTOR_CAPABILITY;
1029         command |= UCSI_CONNECTOR_NUMBER(con->num);
1030         ret = ucsi_send_command(ucsi, command, &con->cap, sizeof(con->cap));
1031         if (ret < 0)
1032                 goto out_unlock;
1033
1034         if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DRP)
1035                 cap->data = TYPEC_PORT_DRD;
1036         else if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DFP)
1037                 cap->data = TYPEC_PORT_DFP;
1038         else if (con->cap.op_mode & UCSI_CONCAP_OPMODE_UFP)
1039                 cap->data = TYPEC_PORT_UFP;
1040
1041         if ((con->cap.flags & UCSI_CONCAP_FLAG_PROVIDER) &&
1042             (con->cap.flags & UCSI_CONCAP_FLAG_CONSUMER))
1043                 cap->type = TYPEC_PORT_DRP;
1044         else if (con->cap.flags & UCSI_CONCAP_FLAG_PROVIDER)
1045                 cap->type = TYPEC_PORT_SRC;
1046         else if (con->cap.flags & UCSI_CONCAP_FLAG_CONSUMER)
1047                 cap->type = TYPEC_PORT_SNK;
1048
1049         cap->revision = ucsi->cap.typec_version;
1050         cap->pd_revision = ucsi->cap.pd_version;
1051         cap->prefer_role = TYPEC_NO_PREFERRED_ROLE;
1052
1053         if (con->cap.op_mode & UCSI_CONCAP_OPMODE_AUDIO_ACCESSORY)
1054                 *accessory++ = TYPEC_ACCESSORY_AUDIO;
1055         if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DEBUG_ACCESSORY)
1056                 *accessory = TYPEC_ACCESSORY_DEBUG;
1057
1058         cap->fwnode = ucsi_find_fwnode(con);
1059         cap->driver_data = con;
1060         cap->ops = &ucsi_ops;
1061
1062         ret = ucsi_register_port_psy(con);
1063         if (ret)
1064                 goto out;
1065
1066         /* Register the connector */
1067         con->port = typec_register_port(ucsi->dev, cap);
1068         if (IS_ERR(con->port)) {
1069                 ret = PTR_ERR(con->port);
1070                 goto out;
1071         }
1072
1073         /* Alternate modes */
1074         ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_CON);
1075         if (ret) {
1076                 dev_err(ucsi->dev, "con%d: failed to register alt modes\n",
1077                         con->num);
1078                 goto out;
1079         }
1080
1081         /* Get the status */
1082         command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num);
1083         ret = ucsi_send_command(ucsi, command, &con->status, sizeof(con->status));
1084         if (ret < 0) {
1085                 dev_err(ucsi->dev, "con%d: failed to get status\n", con->num);
1086                 ret = 0;
1087                 goto out;
1088         }
1089         ret = 0; /* ucsi_send_command() returns length on success */
1090
1091         switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) {
1092         case UCSI_CONSTAT_PARTNER_TYPE_UFP:
1093         case UCSI_CONSTAT_PARTNER_TYPE_CABLE:
1094         case UCSI_CONSTAT_PARTNER_TYPE_CABLE_AND_UFP:
1095                 typec_set_data_role(con->port, TYPEC_HOST);
1096                 break;
1097         case UCSI_CONSTAT_PARTNER_TYPE_DFP:
1098                 typec_set_data_role(con->port, TYPEC_DEVICE);
1099                 break;
1100         default:
1101                 break;
1102         }
1103
1104         /* Check if there is already something connected */
1105         if (con->status.flags & UCSI_CONSTAT_CONNECTED) {
1106                 typec_set_pwr_role(con->port,
1107                                   !!(con->status.flags & UCSI_CONSTAT_PWR_DIR));
1108                 ucsi_pwr_opmode_change(con);
1109                 ucsi_register_partner(con);
1110                 ucsi_port_psy_changed(con);
1111         }
1112
1113         if (con->partner) {
1114                 ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_SOP);
1115                 if (ret) {
1116                         dev_err(ucsi->dev,
1117                                 "con%d: failed to register alternate modes\n",
1118                                 con->num);
1119                         ret = 0;
1120                 } else {
1121                         ucsi_altmode_update_active(con);
1122                 }
1123         }
1124
1125         trace_ucsi_register_port(con->num, &con->status);
1126
1127 out:
1128         fwnode_handle_put(cap->fwnode);
1129 out_unlock:
1130         mutex_unlock(&con->lock);
1131         return ret;
1132 }
1133
1134 /**
1135  * ucsi_init - Initialize UCSI interface
1136  * @ucsi: UCSI to be initialized
1137  *
1138  * Registers all ports @ucsi has and enables all notification events.
1139  */
1140 static int ucsi_init(struct ucsi *ucsi)
1141 {
1142         struct ucsi_connector *con;
1143         u64 command;
1144         int ret;
1145         int i;
1146
1147         /* Reset the PPM */
1148         ret = ucsi_reset_ppm(ucsi);
1149         if (ret) {
1150                 dev_err(ucsi->dev, "failed to reset PPM!\n");
1151                 goto err;
1152         }
1153
1154         /* Enable basic notifications */
1155         ucsi->ntfy = UCSI_ENABLE_NTFY_CMD_COMPLETE | UCSI_ENABLE_NTFY_ERROR;
1156         command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy;
1157         ret = ucsi_send_command(ucsi, command, NULL, 0);
1158         if (ret < 0)
1159                 goto err_reset;
1160
1161         /* Get PPM capabilities */
1162         command = UCSI_GET_CAPABILITY;
1163         ret = ucsi_send_command(ucsi, command, &ucsi->cap, sizeof(ucsi->cap));
1164         if (ret < 0)
1165                 goto err_reset;
1166
1167         if (!ucsi->cap.num_connectors) {
1168                 ret = -ENODEV;
1169                 goto err_reset;
1170         }
1171
1172         /* Allocate the connectors. Released in ucsi_unregister_ppm() */
1173         ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1,
1174                                   sizeof(*ucsi->connector), GFP_KERNEL);
1175         if (!ucsi->connector) {
1176                 ret = -ENOMEM;
1177                 goto err_reset;
1178         }
1179
1180         /* Register all connectors */
1181         for (i = 0; i < ucsi->cap.num_connectors; i++) {
1182                 ret = ucsi_register_port(ucsi, i);
1183                 if (ret)
1184                         goto err_unregister;
1185         }
1186
1187         /* Enable all notifications */
1188         ucsi->ntfy = UCSI_ENABLE_NTFY_ALL;
1189         command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy;
1190         ret = ucsi_send_command(ucsi, command, NULL, 0);
1191         if (ret < 0)
1192                 goto err_unregister;
1193
1194         return 0;
1195
1196 err_unregister:
1197         for (con = ucsi->connector; con->port; con++) {
1198                 ucsi_unregister_partner(con);
1199                 ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
1200                 ucsi_unregister_port_psy(con);
1201                 typec_unregister_port(con->port);
1202                 con->port = NULL;
1203         }
1204
1205 err_reset:
1206         ucsi_reset_ppm(ucsi);
1207 err:
1208         return ret;
1209 }
1210
1211 static void ucsi_init_work(struct work_struct *work)
1212 {
1213         struct ucsi *ucsi = container_of(work, struct ucsi, work);
1214         int ret;
1215
1216         ret = ucsi_init(ucsi);
1217         if (ret)
1218                 dev_err(ucsi->dev, "PPM init failed (%d)\n", ret);
1219 }
1220
1221 /**
1222  * ucsi_get_drvdata - Return private driver data pointer
1223  * @ucsi: UCSI interface
1224  */
1225 void *ucsi_get_drvdata(struct ucsi *ucsi)
1226 {
1227         return ucsi->driver_data;
1228 }
1229 EXPORT_SYMBOL_GPL(ucsi_get_drvdata);
1230
1231 /**
1232  * ucsi_get_drvdata - Assign private driver data pointer
1233  * @ucsi: UCSI interface
1234  * @data: Private data pointer
1235  */
1236 void ucsi_set_drvdata(struct ucsi *ucsi, void *data)
1237 {
1238         ucsi->driver_data = data;
1239 }
1240 EXPORT_SYMBOL_GPL(ucsi_set_drvdata);
1241
1242 /**
1243  * ucsi_create - Allocate UCSI instance
1244  * @dev: Device interface to the PPM (Platform Policy Manager)
1245  * @ops: I/O routines
1246  */
1247 struct ucsi *ucsi_create(struct device *dev, const struct ucsi_operations *ops)
1248 {
1249         struct ucsi *ucsi;
1250
1251         if (!ops || !ops->read || !ops->sync_write || !ops->async_write)
1252                 return ERR_PTR(-EINVAL);
1253
1254         ucsi = kzalloc(sizeof(*ucsi), GFP_KERNEL);
1255         if (!ucsi)
1256                 return ERR_PTR(-ENOMEM);
1257
1258         INIT_WORK(&ucsi->work, ucsi_init_work);
1259         mutex_init(&ucsi->ppm_lock);
1260         ucsi->dev = dev;
1261         ucsi->ops = ops;
1262
1263         return ucsi;
1264 }
1265 EXPORT_SYMBOL_GPL(ucsi_create);
1266
1267 /**
1268  * ucsi_destroy - Free UCSI instance
1269  * @ucsi: UCSI instance to be freed
1270  */
1271 void ucsi_destroy(struct ucsi *ucsi)
1272 {
1273         kfree(ucsi);
1274 }
1275 EXPORT_SYMBOL_GPL(ucsi_destroy);
1276
1277 /**
1278  * ucsi_register - Register UCSI interface
1279  * @ucsi: UCSI instance
1280  */
1281 int ucsi_register(struct ucsi *ucsi)
1282 {
1283         int ret;
1284
1285         ret = ucsi->ops->read(ucsi, UCSI_VERSION, &ucsi->version,
1286                               sizeof(ucsi->version));
1287         if (ret)
1288                 return ret;
1289
1290         if (!ucsi->version)
1291                 return -ENODEV;
1292
1293         queue_work(system_long_wq, &ucsi->work);
1294
1295         return 0;
1296 }
1297 EXPORT_SYMBOL_GPL(ucsi_register);
1298
1299 /**
1300  * ucsi_unregister - Unregister UCSI interface
1301  * @ucsi: UCSI interface to be unregistered
1302  *
1303  * Unregister UCSI interface that was created with ucsi_register().
1304  */
1305 void ucsi_unregister(struct ucsi *ucsi)
1306 {
1307         u64 cmd = UCSI_SET_NOTIFICATION_ENABLE;
1308         int i;
1309
1310         /* Make sure that we are not in the middle of driver initialization */
1311         cancel_work_sync(&ucsi->work);
1312
1313         /* Disable notifications */
1314         ucsi->ops->async_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
1315
1316         for (i = 0; i < ucsi->cap.num_connectors; i++) {
1317                 cancel_work_sync(&ucsi->connector[i].work);
1318                 ucsi_unregister_partner(&ucsi->connector[i]);
1319                 ucsi_unregister_altmodes(&ucsi->connector[i],
1320                                          UCSI_RECIPIENT_CON);
1321                 ucsi_unregister_port_psy(&ucsi->connector[i]);
1322                 typec_unregister_port(ucsi->connector[i].port);
1323         }
1324
1325         kfree(ucsi->connector);
1326 }
1327 EXPORT_SYMBOL_GPL(ucsi_unregister);
1328
1329 MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
1330 MODULE_LICENSE("GPL v2");
1331 MODULE_DESCRIPTION("USB Type-C Connector System Software Interface driver");