drivers/soundwire/bus.c

   1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
   2 // Copyright(c) 2015-17 Intel Corporation.
   3
   4 #include <linux/acpi.h>
   5 #include <linux/delay.h>
   6 #include <linux/mod_devicetable.h>
   7 #include <linux/pm_runtime.h>
   8 #include <linux/soundwire/sdw_registers.h>
   9 #include <linux/soundwire/sdw.h>
  10 #include <linux/soundwire/sdw_type.h>
  11 #include "bus.h"
  12 #include "sysfs_local.h"
  13
  14 static DEFINE_IDA(sdw_ida);
  15
  16 static int sdw_get_id(struct sdw_bus *bus)
  17 {
  18         int rc = ida_alloc(&sdw_ida, GFP_KERNEL);
  19
  20         if (rc < 0)
  21                 return rc;
  22
  23         bus->id = rc;
  24         return 0;
  25 }
  26
  27 /**
  28  * sdw_bus_master_add() - add a bus Master instance
  29  * @bus: bus instance
  30  * @parent: parent device
  31  * @fwnode: firmware node handle
  32  *
  33  * Initializes the bus instance, read properties and create child
  34  * devices.
  35  */
  36 int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
  37                        struct fwnode_handle *fwnode)
  38 {
  39         struct sdw_master_prop *prop = NULL;
  40         int ret;
  41
  42         if (!parent) {
  43                 pr_err("SoundWire parent device is not set\n");
  44                 return -ENODEV;
  45         }
  46
  47         ret = sdw_get_id(bus);
  48         if (ret < 0) {
  49                 dev_err(parent, "Failed to get bus id\n");
  50                 return ret;
  51         }
  52
  53         ret = sdw_master_device_add(bus, parent, fwnode);
  54         if (ret < 0) {
  55                 dev_err(parent, "Failed to add master device at link %d\n",
  56                         bus->link_id);
  57                 return ret;
  58         }
  59
  60         if (!bus->ops) {
  61                 dev_err(bus->dev, "SoundWire Bus ops are not set\n");
  62                 return -EINVAL;
  63         }
  64
  65         if (!bus->compute_params) {
  66                 dev_err(bus->dev,
  67                         "Bandwidth allocation not configured, compute_params no set\n");
  68                 return -EINVAL;
  69         }
  70
  71         mutex_init(&bus->msg_lock);
  72         mutex_init(&bus->bus_lock);
  73         INIT_LIST_HEAD(&bus->slaves);
  74         INIT_LIST_HEAD(&bus->m_rt_list);
  75
  76         /*
  77          * Initialize multi_link flag
  78          * TODO: populate this flag by reading property from FW node
  79          */
  80         bus->multi_link = false;
  81         if (bus->ops->read_prop) {
  82                 ret = bus->ops->read_prop(bus);
  83                 if (ret < 0) {
  84                         dev_err(bus->dev,
  85                                 "Bus read properties failed:%d\n", ret);
  86                         return ret;
  87                 }
  88         }
  89
  90         sdw_bus_debugfs_init(bus);
  91
  92         /*
  93          * Device numbers in SoundWire are 0 through 15. Enumeration device
  94          * number (0), Broadcast device number (15), Group numbers (12 and
  95          * 13) and Master device number (14) are not used for assignment so
  96          * mask these and other higher bits.
  97          */
  98
  99         /* Set higher order bits */
 100         *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
 101
 102         /* Set enumuration device number and broadcast device number */
 103         set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
 104         set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
 105
 106         /* Set group device numbers and master device number */
 107         set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
 108         set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
 109         set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
 110
 111         /*
 112          * SDW is an enumerable bus, but devices can be powered off. So,
 113          * they won't be able to report as present.
 114          *
 115          * Create Slave devices based on Slaves described in
 116          * the respective firmware (ACPI/DT)
 117          */
 118         if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
 119                 ret = sdw_acpi_find_slaves(bus);
 120         else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
 121                 ret = sdw_of_find_slaves(bus);
 122         else
 123                 ret = -ENOTSUPP; /* No ACPI/DT so error out */
 124
 125         if (ret < 0) {
 126                 dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
 127                 return ret;
 128         }
 129
 130         /*
 131          * Initialize clock values based on Master properties. The max
 132          * frequency is read from max_clk_freq property. Current assumption
 133          * is that the bus will start at highest clock frequency when
 134          * powered on.
 135          *
 136          * Default active bank will be 0 as out of reset the Slaves have
 137          * to start with bank 0 (Table 40 of Spec)
 138          */
 139         prop = &bus->prop;
 140         bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
 141         bus->params.curr_dr_freq = bus->params.max_dr_freq;
 142         bus->params.curr_bank = SDW_BANK0;
 143         bus->params.next_bank = SDW_BANK1;
 144
 145         return 0;
 146 }
 147 EXPORT_SYMBOL(sdw_bus_master_add);
 148
 149 static int sdw_delete_slave(struct device *dev, void *data)
 150 {
 151         struct sdw_slave *slave = dev_to_sdw_dev(dev);
 152         struct sdw_bus *bus = slave->bus;
 153
 154         pm_runtime_disable(dev);
 155
 156         sdw_slave_debugfs_exit(slave);
 157
 158         mutex_lock(&bus->bus_lock);
 159
 160         if (slave->dev_num) /* clear dev_num if assigned */
 161                 clear_bit(slave->dev_num, bus->assigned);
 162
 163         list_del_init(&slave->node);
 164         mutex_unlock(&bus->bus_lock);
 165
 166         device_unregister(dev);
 167         return 0;
 168 }
 169
 170 /**
 171  * sdw_bus_master_delete() - delete the bus master instance
 172  * @bus: bus to be deleted
 173  *
 174  * Remove the instance, delete the child devices.
 175  */
 176 void sdw_bus_master_delete(struct sdw_bus *bus)
 177 {
 178         device_for_each_child(bus->dev, NULL, sdw_delete_slave);
 179         sdw_master_device_del(bus);
 180
 181         sdw_bus_debugfs_exit(bus);
 182         ida_free(&sdw_ida, bus->id);
 183 }
 184 EXPORT_SYMBOL(sdw_bus_master_delete);
 185
 186 /*
 187  * SDW IO Calls
 188  */
 189
 190 static inline int find_response_code(enum sdw_command_response resp)
 191 {
 192         switch (resp) {
 193         case SDW_CMD_OK:
 194                 return 0;
 195
 196         case SDW_CMD_IGNORED:
 197                 return -ENODATA;
 198
 199         case SDW_CMD_TIMEOUT:
 200                 return -ETIMEDOUT;
 201
 202         default:
 203                 return -EIO;
 204         }
 205 }
 206
 207 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 208 {
 209         int retry = bus->prop.err_threshold;
 210         enum sdw_command_response resp;
 211         int ret = 0, i;
 212
 213         for (i = 0; i <= retry; i++) {
 214                 resp = bus->ops->xfer_msg(bus, msg);
 215                 ret = find_response_code(resp);
 216
 217                 /* if cmd is ok or ignored return */
 218                 if (ret == 0 || ret == -ENODATA)
 219                         return ret;
 220         }
 221
 222         return ret;
 223 }
 224
 225 static inline int do_transfer_defer(struct sdw_bus *bus,
 226                                     struct sdw_msg *msg,
 227                                     struct sdw_defer *defer)
 228 {
 229         int retry = bus->prop.err_threshold;
 230         enum sdw_command_response resp;
 231         int ret = 0, i;
 232
 233         defer->msg = msg;
 234         defer->length = msg->len;
 235         init_completion(&defer->complete);
 236
 237         for (i = 0; i <= retry; i++) {
 238                 resp = bus->ops->xfer_msg_defer(bus, msg, defer);
 239                 ret = find_response_code(resp);
 240                 /* if cmd is ok or ignored return */
 241                 if (ret == 0 || ret == -ENODATA)
 242                         return ret;
 243         }
 244
 245         return ret;
 246 }
 247
 248 static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num)
 249 {
 250         int retry = bus->prop.err_threshold;
 251         enum sdw_command_response resp;
 252         int ret = 0, i;
 253
 254         for (i = 0; i <= retry; i++) {
 255                 resp = bus->ops->reset_page_addr(bus, dev_num);
 256                 ret = find_response_code(resp);
 257                 /* if cmd is ok or ignored return */
 258                 if (ret == 0 || ret == -ENODATA)
 259                         return ret;
 260         }
 261
 262         return ret;
 263 }
 264
 265 static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
 266 {
 267         int ret;
 268
 269         ret = do_transfer(bus, msg);
 270         if (ret != 0 && ret != -ENODATA)
 271                 dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
 272                         msg->dev_num, ret,
 273                         (msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
 274                         msg->addr, msg->len);
 275
 276         if (msg->page)
 277                 sdw_reset_page(bus, msg->dev_num);
 278
 279         return ret;
 280 }
 281
 282 /**
 283  * sdw_transfer() - Synchronous transfer message to a SDW Slave device
 284  * @bus: SDW bus
 285  * @msg: SDW message to be xfered
 286  */
 287 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 288 {
 289         int ret;
 290
 291         mutex_lock(&bus->msg_lock);
 292
 293         ret = sdw_transfer_unlocked(bus, msg);
 294
 295         mutex_unlock(&bus->msg_lock);
 296
 297         return ret;
 298 }
 299
 300 /**
 301  * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
 302  * @bus: SDW bus
 303  * @msg: SDW message to be xfered
 304  * @defer: Defer block for signal completion
 305  *
 306  * Caller needs to hold the msg_lock lock while calling this
 307  */
 308 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg,
 309                        struct sdw_defer *defer)
 310 {
 311         int ret;
 312
 313         if (!bus->ops->xfer_msg_defer)
 314                 return -ENOTSUPP;
 315
 316         ret = do_transfer_defer(bus, msg, defer);
 317         if (ret != 0 && ret != -ENODATA)
 318                 dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
 319                         msg->dev_num, ret);
 320
 321         if (msg->page)
 322                 sdw_reset_page(bus, msg->dev_num);
 323
 324         return ret;
 325 }
 326
 327 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
 328                  u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
 329 {
 330         memset(msg, 0, sizeof(*msg));
 331         msg->addr = addr; /* addr is 16 bit and truncated here */
 332         msg->len = count;
 333         msg->dev_num = dev_num;
 334         msg->flags = flags;
 335         msg->buf = buf;
 336
 337         if (addr < SDW_REG_NO_PAGE) /* no paging area */
 338                 return 0;
 339
 340         if (addr >= SDW_REG_MAX) { /* illegal addr */
 341                 pr_err("SDW: Invalid address %x passed\n", addr);
 342                 return -EINVAL;
 343         }
 344
 345         if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
 346                 if (slave && !slave->prop.paging_support)
 347                         return 0;
 348                 /* no need for else as that will fall-through to paging */
 349         }
 350
 351         /* paging mandatory */
 352         if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
 353                 pr_err("SDW: Invalid device for paging :%d\n", dev_num);
 354                 return -EINVAL;
 355         }
 356
 357         if (!slave) {
 358                 pr_err("SDW: No slave for paging addr\n");
 359                 return -EINVAL;
 360         }
 361
 362         if (!slave->prop.paging_support) {
 363                 dev_err(&slave->dev,
 364                         "address %x needs paging but no support\n", addr);
 365                 return -EINVAL;
 366         }
 367
 368         msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
 369         msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
 370         msg->addr |= BIT(15);
 371         msg->page = true;
 372
 373         return 0;
 374 }
 375
 376 /*
 377  * Read/Write IO functions.
 378  * no_pm versions can only be called by the bus, e.g. while enumerating or
 379  * handling suspend-resume sequences.
 380  * all clients need to use the pm versions
 381  */
 382
 383 static int
 384 sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 385 {
 386         struct sdw_msg msg;
 387         int ret;
 388
 389         ret = sdw_fill_msg(&msg, slave, addr, count,
 390                            slave->dev_num, SDW_MSG_FLAG_READ, val);
 391         if (ret < 0)
 392                 return ret;
 393
 394         ret = sdw_transfer(slave->bus, &msg);
 395         if (slave->is_mockup_device)
 396                 ret = 0;
 397         return ret;
 398 }
 399
 400 static int
 401 sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 402 {
 403         struct sdw_msg msg;
 404         int ret;
 405
 406         ret = sdw_fill_msg(&msg, slave, addr, count,
 407                            slave->dev_num, SDW_MSG_FLAG_WRITE, (u8 *)val);
 408         if (ret < 0)
 409                 return ret;
 410
 411         ret = sdw_transfer(slave->bus, &msg);
 412         if (slave->is_mockup_device)
 413                 ret = 0;
 414         return ret;
 415 }
 416
 417 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
 418 {
 419         return sdw_nwrite_no_pm(slave, addr, 1, &value);
 420 }
 421 EXPORT_SYMBOL(sdw_write_no_pm);
 422
 423 static int
 424 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
 425 {
 426         struct sdw_msg msg;
 427         u8 buf;
 428         int ret;
 429
 430         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 431                            SDW_MSG_FLAG_READ, &buf);
 432         if (ret < 0)
 433                 return ret;
 434
 435         ret = sdw_transfer(bus, &msg);
 436         if (ret < 0)
 437                 return ret;
 438
 439         return buf;
 440 }
 441
 442 static int
 443 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 444 {
 445         struct sdw_msg msg;
 446         int ret;
 447
 448         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 449                            SDW_MSG_FLAG_WRITE, &value);
 450         if (ret < 0)
 451                 return ret;
 452
 453         return sdw_transfer(bus, &msg);
 454 }
 455
 456 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
 457 {
 458         struct sdw_msg msg;
 459         u8 buf;
 460         int ret;
 461
 462         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 463                            SDW_MSG_FLAG_READ, &buf);
 464         if (ret < 0)
 465                 return ret;
 466
 467         ret = sdw_transfer_unlocked(bus, &msg);
 468         if (ret < 0)
 469                 return ret;
 470
 471         return buf;
 472 }
 473 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
 474
 475 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 476 {
 477         struct sdw_msg msg;
 478         int ret;
 479
 480         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 481                            SDW_MSG_FLAG_WRITE, &value);
 482         if (ret < 0)
 483                 return ret;
 484
 485         return sdw_transfer_unlocked(bus, &msg);
 486 }
 487 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
 488
 489 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 490 {
 491         u8 buf;
 492         int ret;
 493
 494         ret = sdw_nread_no_pm(slave, addr, 1, &buf);
 495         if (ret < 0)
 496                 return ret;
 497         else
 498                 return buf;
 499 }
 500 EXPORT_SYMBOL(sdw_read_no_pm);
 501
 502 int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 503 {
 504         int tmp;
 505
 506         tmp = sdw_read_no_pm(slave, addr);
 507         if (tmp < 0)
 508                 return tmp;
 509
 510         tmp = (tmp & ~mask) | val;
 511         return sdw_write_no_pm(slave, addr, tmp);
 512 }
 513 EXPORT_SYMBOL(sdw_update_no_pm);
 514
 515 /* Read-Modify-Write Slave register */
 516 int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 517 {
 518         int tmp;
 519
 520         tmp = sdw_read(slave, addr);
 521         if (tmp < 0)
 522                 return tmp;
 523
 524         tmp = (tmp & ~mask) | val;
 525         return sdw_write(slave, addr, tmp);
 526 }
 527 EXPORT_SYMBOL(sdw_update);
 528
 529 /**
 530  * sdw_nread() - Read "n" contiguous SDW Slave registers
 531  * @slave: SDW Slave
 532  * @addr: Register address
 533  * @count: length
 534  * @val: Buffer for values to be read
 535  */
 536 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 537 {
 538         int ret;
 539
 540         ret = pm_runtime_get_sync(&slave->dev);
 541         if (ret < 0 && ret != -EACCES) {
 542                 pm_runtime_put_noidle(&slave->dev);
 543                 return ret;
 544         }
 545
 546         ret = sdw_nread_no_pm(slave, addr, count, val);
 547
 548         pm_runtime_mark_last_busy(&slave->dev);
 549         pm_runtime_put(&slave->dev);
 550
 551         return ret;
 552 }
 553 EXPORT_SYMBOL(sdw_nread);
 554
 555 /**
 556  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
 557  * @slave: SDW Slave
 558  * @addr: Register address
 559  * @count: length
 560  * @val: Buffer for values to be written
 561  */
 562 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 563 {
 564         int ret;
 565
 566         ret = pm_runtime_get_sync(&slave->dev);
 567         if (ret < 0 && ret != -EACCES) {
 568                 pm_runtime_put_noidle(&slave->dev);
 569                 return ret;
 570         }
 571
 572         ret = sdw_nwrite_no_pm(slave, addr, count, val);
 573
 574         pm_runtime_mark_last_busy(&slave->dev);
 575         pm_runtime_put(&slave->dev);
 576
 577         return ret;
 578 }
 579 EXPORT_SYMBOL(sdw_nwrite);
 580
 581 /**
 582  * sdw_read() - Read a SDW Slave register
 583  * @slave: SDW Slave
 584  * @addr: Register address
 585  */
 586 int sdw_read(struct sdw_slave *slave, u32 addr)
 587 {
 588         u8 buf;
 589         int ret;
 590
 591         ret = sdw_nread(slave, addr, 1, &buf);
 592         if (ret < 0)
 593                 return ret;
 594
 595         return buf;
 596 }
 597 EXPORT_SYMBOL(sdw_read);
 598
 599 /**
 600  * sdw_write() - Write a SDW Slave register
 601  * @slave: SDW Slave
 602  * @addr: Register address
 603  * @value: Register value
 604  */
 605 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
 606 {
 607         return sdw_nwrite(slave, addr, 1, &value);
 608 }
 609 EXPORT_SYMBOL(sdw_write);
 610
 611 /*
 612  * SDW alert handling
 613  */
 614
 615 /* called with bus_lock held */
 616 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
 617 {
 618         struct sdw_slave *slave;
 619
 620         list_for_each_entry(slave, &bus->slaves, node) {
 621                 if (slave->dev_num == i)
 622                         return slave;
 623         }
 624
 625         return NULL;
 626 }
 627
 628 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
 629 {
 630         if (slave->id.mfg_id != id.mfg_id ||
 631             slave->id.part_id != id.part_id ||
 632             slave->id.class_id != id.class_id ||
 633             (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
 634              slave->id.unique_id != id.unique_id))
 635                 return -ENODEV;
 636
 637         return 0;
 638 }
 639 EXPORT_SYMBOL(sdw_compare_devid);
 640
 641 /* called with bus_lock held */
 642 static int sdw_get_device_num(struct sdw_slave *slave)
 643 {
 644         int bit;
 645
 646         bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
 647         if (bit == SDW_MAX_DEVICES) {
 648                 bit = -ENODEV;
 649                 goto err;
 650         }
 651
 652         /*
 653          * Do not update dev_num in Slave data structure here,
 654          * Update once program dev_num is successful
 655          */
 656         set_bit(bit, slave->bus->assigned);
 657
 658 err:
 659         return bit;
 660 }
 661
 662 static int sdw_assign_device_num(struct sdw_slave *slave)
 663 {
 664         struct sdw_bus *bus = slave->bus;
 665         int ret, dev_num;
 666         bool new_device = false;
 667
 668         /* check first if device number is assigned, if so reuse that */
 669         if (!slave->dev_num) {
 670                 if (!slave->dev_num_sticky) {
 671                         mutex_lock(&slave->bus->bus_lock);
 672                         dev_num = sdw_get_device_num(slave);
 673                         mutex_unlock(&slave->bus->bus_lock);
 674                         if (dev_num < 0) {
 675                                 dev_err(bus->dev, "Get dev_num failed: %d\n",
 676                                         dev_num);
 677                                 return dev_num;
 678                         }
 679                         slave->dev_num = dev_num;
 680                         slave->dev_num_sticky = dev_num;
 681                         new_device = true;
 682                 } else {
 683                         slave->dev_num = slave->dev_num_sticky;
 684                 }
 685         }
 686
 687         if (!new_device)
 688                 dev_dbg(bus->dev,
 689                         "Slave already registered, reusing dev_num:%d\n",
 690                         slave->dev_num);
 691
 692         /* Clear the slave->dev_num to transfer message on device 0 */
 693         dev_num = slave->dev_num;
 694         slave->dev_num = 0;
 695
 696         ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
 697         if (ret < 0) {
 698                 dev_err(bus->dev, "Program device_num %d failed: %d\n",
 699                         dev_num, ret);
 700                 return ret;
 701         }
 702
 703         /* After xfer of msg, restore dev_num */
 704         slave->dev_num = slave->dev_num_sticky;
 705
 706         return 0;
 707 }
 708
 709 void sdw_extract_slave_id(struct sdw_bus *bus,
 710                           u64 addr, struct sdw_slave_id *id)
 711 {
 712         dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 713
 714         id->sdw_version = SDW_VERSION(addr);
 715         id->unique_id = SDW_UNIQUE_ID(addr);
 716         id->mfg_id = SDW_MFG_ID(addr);
 717         id->part_id = SDW_PART_ID(addr);
 718         id->class_id = SDW_CLASS_ID(addr);
 719
 720         dev_dbg(bus->dev,
 721                 "SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
 722                 id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 723 }
 724 EXPORT_SYMBOL(sdw_extract_slave_id);
 725
 726 static int sdw_program_device_num(struct sdw_bus *bus)
 727 {
 728         u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
 729         struct sdw_slave *slave, *_s;
 730         struct sdw_slave_id id;
 731         struct sdw_msg msg;
 732         bool found;
 733         int count = 0, ret;
 734         u64 addr;
 735
 736         /* No Slave, so use raw xfer api */
 737         ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
 738                            SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
 739         if (ret < 0)
 740                 return ret;
 741
 742         do {
 743                 ret = sdw_transfer(bus, &msg);
 744                 if (ret == -ENODATA) { /* end of device id reads */
 745                         dev_dbg(bus->dev, "No more devices to enumerate\n");
 746                         ret = 0;
 747                         break;
 748                 }
 749                 if (ret < 0) {
 750                         dev_err(bus->dev, "DEVID read fail:%d\n", ret);
 751                         break;
 752                 }
 753
 754                 /*
 755                  * Construct the addr and extract. Cast the higher shift
 756                  * bits to avoid truncation due to size limit.
 757                  */
 758                 addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
 759                         ((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
 760                         ((u64)buf[0] << 40);
 761
 762                 sdw_extract_slave_id(bus, addr, &id);
 763
 764                 found = false;
 765                 /* Now compare with entries */
 766                 list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
 767                         if (sdw_compare_devid(slave, id) == 0) {
 768                                 found = true;
 769
 770                                 /*
 771                                  * Assign a new dev_num to this Slave and
 772                                  * not mark it present. It will be marked
 773                                  * present after it reports ATTACHED on new
 774                                  * dev_num
 775                                  */
 776                                 ret = sdw_assign_device_num(slave);
 777                                 if (ret < 0) {
 778                                         dev_err(bus->dev,
 779                                                 "Assign dev_num failed:%d\n",
 780                                                 ret);
 781                                         return ret;
 782                                 }
 783
 784                                 break;
 785                         }
 786                 }
 787
 788                 if (!found) {
 789                         /* TODO: Park this device in Group 13 */
 790
 791                         /*
 792                          * add Slave device even if there is no platform
 793                          * firmware description. There will be no driver probe
 794                          * but the user/integration will be able to see the
 795                          * device, enumeration status and device number in sysfs
 796                          */
 797                         sdw_slave_add(bus, &id, NULL);
 798
 799                         dev_err(bus->dev, "Slave Entry not found\n");
 800                 }
 801
 802                 count++;
 803
 804                 /*
 805                  * Check till error out or retry (count) exhausts.
 806                  * Device can drop off and rejoin during enumeration
 807                  * so count till twice the bound.
 808                  */
 809
 810         } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
 811
 812         return ret;
 813 }
 814
 815 static void sdw_modify_slave_status(struct sdw_slave *slave,
 816                                     enum sdw_slave_status status)
 817 {
 818         struct sdw_bus *bus = slave->bus;
 819
 820         mutex_lock(&bus->bus_lock);
 821
 822         dev_vdbg(bus->dev,
 823                  "%s: changing status slave %d status %d new status %d\n",
 824                  __func__, slave->dev_num, slave->status, status);
 825
 826         if (status == SDW_SLAVE_UNATTACHED) {
 827                 dev_dbg(&slave->dev,
 828                         "%s: initializing enumeration and init completion for Slave %d\n",
 829                         __func__, slave->dev_num);
 830
 831                 init_completion(&slave->enumeration_complete);
 832                 init_completion(&slave->initialization_complete);
 833
 834         } else if ((status == SDW_SLAVE_ATTACHED) &&
 835                    (slave->status == SDW_SLAVE_UNATTACHED)) {
 836                 dev_dbg(&slave->dev,
 837                         "%s: signaling enumeration completion for Slave %d\n",
 838                         __func__, slave->dev_num);
 839
 840                 complete(&slave->enumeration_complete);
 841         }
 842         slave->status = status;
 843         mutex_unlock(&bus->bus_lock);
 844 }
 845
 846 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
 847                                        enum sdw_clk_stop_mode mode,
 848                                        enum sdw_clk_stop_type type)
 849 {
 850         int ret = 0;
 851
 852         mutex_lock(&slave->sdw_dev_lock);
 853
 854         if (slave->probed)  {
 855                 struct device *dev = &slave->dev;
 856                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
 857
 858                 if (drv->ops && drv->ops->clk_stop)
 859                         ret = drv->ops->clk_stop(slave, mode, type);
 860         }
 861
 862         mutex_unlock(&slave->sdw_dev_lock);
 863
 864         return ret;
 865 }
 866
 867 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
 868                                       enum sdw_clk_stop_mode mode,
 869                                       bool prepare)
 870 {
 871         bool wake_en;
 872         u32 val = 0;
 873         int ret;
 874
 875         wake_en = slave->prop.wake_capable;
 876
 877         if (prepare) {
 878                 val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
 879
 880                 if (mode == SDW_CLK_STOP_MODE1)
 881                         val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
 882
 883                 if (wake_en)
 884                         val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
 885         } else {
 886                 ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
 887                 if (ret < 0) {
 888                         if (ret != -ENODATA)
 889                                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
 890                         return ret;
 891                 }
 892                 val = ret;
 893                 val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
 894         }
 895
 896         ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
 897
 898         if (ret < 0 && ret != -ENODATA)
 899                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
 900
 901         return ret;
 902 }
 903
 904 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num)
 905 {
 906         int retry = bus->clk_stop_timeout;
 907         int val;
 908
 909         do {
 910                 val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
 911                 if (val < 0) {
 912                         if (val != -ENODATA)
 913                                 dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
 914                         return val;
 915                 }
 916                 val &= SDW_SCP_STAT_CLK_STP_NF;
 917                 if (!val) {
 918                         dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d\n",
 919                                 dev_num);
 920                         return 0;
 921                 }
 922
 923                 usleep_range(1000, 1500);
 924                 retry--;
 925         } while (retry);
 926
 927         dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d\n",
 928                 dev_num);
 929
 930         return -ETIMEDOUT;
 931 }
 932
 933 /**
 934  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
 935  *
 936  * @bus: SDW bus instance
 937  *
 938  * Query Slave for clock stop mode and prepare for that mode.
 939  */
 940 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
 941 {
 942         bool simple_clk_stop = true;
 943         struct sdw_slave *slave;
 944         bool is_slave = false;
 945         int ret = 0;
 946
 947         /*
 948          * In order to save on transition time, prepare
 949          * each Slave and then wait for all Slave(s) to be
 950          * prepared for clock stop.
 951          * If one of the Slave devices has lost sync and
 952          * replies with Command Ignored/-ENODATA, we continue
 953          * the loop
 954          */
 955         list_for_each_entry(slave, &bus->slaves, node) {
 956                 if (!slave->dev_num)
 957                         continue;
 958
 959                 if (slave->status != SDW_SLAVE_ATTACHED &&
 960                     slave->status != SDW_SLAVE_ALERT)
 961                         continue;
 962
 963                 /* Identify if Slave(s) are available on Bus */
 964                 is_slave = true;
 965
 966                 ret = sdw_slave_clk_stop_callback(slave,
 967                                                   SDW_CLK_STOP_MODE0,
 968                                                   SDW_CLK_PRE_PREPARE);
 969                 if (ret < 0 && ret != -ENODATA) {
 970                         dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
 971                         return ret;
 972                 }
 973
 974                 /* Only prepare a Slave device if needed */
 975                 if (!slave->prop.simple_clk_stop_capable) {
 976                         simple_clk_stop = false;
 977
 978                         ret = sdw_slave_clk_stop_prepare(slave,
 979                                                          SDW_CLK_STOP_MODE0,
 980                                                          true);
 981                         if (ret < 0 && ret != -ENODATA) {
 982                                 dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
 983                                 return ret;
 984                         }
 985                 }
 986         }
 987
 988         /* Skip remaining clock stop preparation if no Slave is attached */
 989         if (!is_slave)
 990                 return 0;
 991
 992         /*
 993          * Don't wait for all Slaves to be ready if they follow the simple
 994          * state machine
 995          */
 996         if (!simple_clk_stop) {
 997                 ret = sdw_bus_wait_for_clk_prep_deprep(bus,
 998                                                        SDW_BROADCAST_DEV_NUM);
 999                 /*
1000                  * if there are no Slave devices present and the reply is
1001                  * Command_Ignored/-ENODATA, we don't need to continue with the
1002                  * flow and can just return here. The error code is not modified
1003                  * and its handling left as an exercise for the caller.
1004                  */
1005                 if (ret < 0)
1006                         return ret;
1007         }
1008
1009         /* Inform slaves that prep is done */
1010         list_for_each_entry(slave, &bus->slaves, node) {
1011                 if (!slave->dev_num)
1012                         continue;
1013
1014                 if (slave->status != SDW_SLAVE_ATTACHED &&
1015                     slave->status != SDW_SLAVE_ALERT)
1016                         continue;
1017
1018                 ret = sdw_slave_clk_stop_callback(slave,
1019                                                   SDW_CLK_STOP_MODE0,
1020                                                   SDW_CLK_POST_PREPARE);
1021
1022                 if (ret < 0 && ret != -ENODATA) {
1023                         dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
1024                         return ret;
1025                 }
1026         }
1027
1028         return 0;
1029 }
1030 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1031
1032 /**
1033  * sdw_bus_clk_stop: stop bus clock
1034  *
1035  * @bus: SDW bus instance
1036  *
1037  * After preparing the Slaves for clock stop, stop the clock by broadcasting
1038  * write to SCP_CTRL register.
1039  */
1040 int sdw_bus_clk_stop(struct sdw_bus *bus)
1041 {
1042         int ret;
1043
1044         /*
1045          * broadcast clock stop now, attached Slaves will ACK this,
1046          * unattached will ignore
1047          */
1048         ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1049                                SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1050         if (ret < 0) {
1051                 if (ret != -ENODATA)
1052                         dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
1053                 return ret;
1054         }
1055
1056         return 0;
1057 }
1058 EXPORT_SYMBOL(sdw_bus_clk_stop);
1059
1060 /**
1061  * sdw_bus_exit_clk_stop: Exit clock stop mode
1062  *
1063  * @bus: SDW bus instance
1064  *
1065  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1066  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1067  * back.
1068  */
1069 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1070 {
1071         bool simple_clk_stop = true;
1072         struct sdw_slave *slave;
1073         bool is_slave = false;
1074         int ret;
1075
1076         /*
1077          * In order to save on transition time, de-prepare
1078          * each Slave and then wait for all Slave(s) to be
1079          * de-prepared after clock resume.
1080          */
1081         list_for_each_entry(slave, &bus->slaves, node) {
1082                 if (!slave->dev_num)
1083                         continue;
1084
1085                 if (slave->status != SDW_SLAVE_ATTACHED &&
1086                     slave->status != SDW_SLAVE_ALERT)
1087                         continue;
1088
1089                 /* Identify if Slave(s) are available on Bus */
1090                 is_slave = true;
1091
1092                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1093                                                   SDW_CLK_PRE_DEPREPARE);
1094                 if (ret < 0)
1095                         dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
1096
1097                 /* Only de-prepare a Slave device if needed */
1098                 if (!slave->prop.simple_clk_stop_capable) {
1099                         simple_clk_stop = false;
1100
1101                         ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
1102                                                          false);
1103
1104                         if (ret < 0)
1105                                 dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
1106                 }
1107         }
1108
1109         /* Skip remaining clock stop de-preparation if no Slave is attached */
1110         if (!is_slave)
1111                 return 0;
1112
1113         /*
1114          * Don't wait for all Slaves to be ready if they follow the simple
1115          * state machine
1116          */
1117         if (!simple_clk_stop) {
1118                 ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM);
1119                 if (ret < 0)
1120                         dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret);
1121         }
1122
1123         list_for_each_entry(slave, &bus->slaves, node) {
1124                 if (!slave->dev_num)
1125                         continue;
1126
1127                 if (slave->status != SDW_SLAVE_ATTACHED &&
1128                     slave->status != SDW_SLAVE_ALERT)
1129                         continue;
1130
1131                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1132                                                   SDW_CLK_POST_DEPREPARE);
1133                 if (ret < 0)
1134                         dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
1135         }
1136
1137         return 0;
1138 }
1139 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1140
1141 int sdw_configure_dpn_intr(struct sdw_slave *slave,
1142                            int port, bool enable, int mask)
1143 {
1144         u32 addr;
1145         int ret;
1146         u8 val = 0;
1147
1148         if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1149                 dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1150                         enable ? "on" : "off");
1151                 mask |= SDW_DPN_INT_TEST_FAIL;
1152         }
1153
1154         addr = SDW_DPN_INTMASK(port);
1155
1156         /* Set/Clear port ready interrupt mask */
1157         if (enable) {
1158                 val |= mask;
1159                 val |= SDW_DPN_INT_PORT_READY;
1160         } else {
1161                 val &= ~(mask);
1162                 val &= ~SDW_DPN_INT_PORT_READY;
1163         }
1164
1165         ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1166         if (ret < 0)
1167                 dev_err(&slave->dev,
1168                         "SDW_DPN_INTMASK write failed:%d\n", val);
1169
1170         return ret;
1171 }
1172
1173 static int sdw_slave_set_frequency(struct sdw_slave *slave)
1174 {
1175         u32 mclk_freq = slave->bus->prop.mclk_freq;
1176         u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1177         unsigned int scale;
1178         u8 scale_index;
1179         u8 base;
1180         int ret;
1181
1182         /*
1183          * frequency base and scale registers are required for SDCA
1184          * devices. They may also be used for 1.2+/non-SDCA devices,
1185          * but we will need a DisCo property to cover this case
1186          */
1187         if (!slave->id.class_id)
1188                 return 0;
1189
1190         if (!mclk_freq) {
1191                 dev_err(&slave->dev,
1192                         "no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1193                 return -EINVAL;
1194         }
1195
1196         /*
1197          * map base frequency using Table 89 of SoundWire 1.2 spec.
1198          * The order of the tests just follows the specification, this
1199          * is not a selection between possible values or a search for
1200          * the best value but just a mapping.  Only one case per platform
1201          * is relevant.
1202          * Some BIOS have inconsistent values for mclk_freq but a
1203          * correct root so we force the mclk_freq to avoid variations.
1204          */
1205         if (!(19200000 % mclk_freq)) {
1206                 mclk_freq = 19200000;
1207                 base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1208         } else if (!(24000000 % mclk_freq)) {
1209                 mclk_freq = 24000000;
1210                 base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1211         } else if (!(24576000 % mclk_freq)) {
1212                 mclk_freq = 24576000;
1213                 base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1214         } else if (!(22579200 % mclk_freq)) {
1215                 mclk_freq = 22579200;
1216                 base = SDW_SCP_BASE_CLOCK_22579200_HZ;
1217         } else if (!(32000000 % mclk_freq)) {
1218                 mclk_freq = 32000000;
1219                 base = SDW_SCP_BASE_CLOCK_32000000_HZ;
1220         } else {
1221                 dev_err(&slave->dev,
1222                         "Unsupported clock base, mclk %d\n",
1223                         mclk_freq);
1224                 return -EINVAL;
1225         }
1226
1227         if (mclk_freq % curr_freq) {
1228                 dev_err(&slave->dev,
1229                         "mclk %d is not multiple of bus curr_freq %d\n",
1230                         mclk_freq, curr_freq);
1231                 return -EINVAL;
1232         }
1233
1234         scale = mclk_freq / curr_freq;
1235
1236         /*
1237          * map scale to Table 90 of SoundWire 1.2 spec - and check
1238          * that the scale is a power of two and maximum 64
1239          */
1240         scale_index = ilog2(scale);
1241
1242         if (BIT(scale_index) != scale || scale_index > 6) {
1243                 dev_err(&slave->dev,
1244                         "No match found for scale %d, bus mclk %d curr_freq %d\n",
1245                         scale, mclk_freq, curr_freq);
1246                 return -EINVAL;
1247         }
1248         scale_index++;
1249
1250         ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1251         if (ret < 0) {
1252                 dev_err(&slave->dev,
1253                         "SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1254                 return ret;
1255         }
1256
1257         /* initialize scale for both banks */
1258         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1259         if (ret < 0) {
1260                 dev_err(&slave->dev,
1261                         "SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1262                 return ret;
1263         }
1264         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1265         if (ret < 0)
1266                 dev_err(&slave->dev,
1267                         "SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1268
1269         dev_dbg(&slave->dev,
1270                 "Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1271                 base, scale_index, mclk_freq, curr_freq);
1272
1273         return ret;
1274 }
1275
1276 static int sdw_initialize_slave(struct sdw_slave *slave)
1277 {
1278         struct sdw_slave_prop *prop = &slave->prop;
1279         int status;
1280         int ret;
1281         u8 val;
1282
1283         ret = sdw_slave_set_frequency(slave);
1284         if (ret < 0)
1285                 return ret;
1286
1287         if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1288                 /* Clear bus clash interrupt before enabling interrupt mask */
1289                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1290                 if (status < 0) {
1291                         dev_err(&slave->dev,
1292                                 "SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1293                         return status;
1294                 }
1295                 if (status & SDW_SCP_INT1_BUS_CLASH) {
1296                         dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1297                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1298                         if (ret < 0) {
1299                                 dev_err(&slave->dev,
1300                                         "SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1301                                 return ret;
1302                         }
1303                 }
1304         }
1305         if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1306             !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1307                 /* Clear parity interrupt before enabling interrupt mask */
1308                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1309                 if (status < 0) {
1310                         dev_err(&slave->dev,
1311                                 "SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1312                         return status;
1313                 }
1314                 if (status & SDW_SCP_INT1_PARITY) {
1315                         dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1316                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1317                         if (ret < 0) {
1318                                 dev_err(&slave->dev,
1319                                         "SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1320                                 return ret;
1321                         }
1322                 }
1323         }
1324
1325         /*
1326          * Set SCP_INT1_MASK register, typically bus clash and
1327          * implementation-defined interrupt mask. The Parity detection
1328          * may not always be correct on startup so its use is
1329          * device-dependent, it might e.g. only be enabled in
1330          * steady-state after a couple of frames.
1331          */
1332         val = slave->prop.scp_int1_mask;
1333
1334         /* Enable SCP interrupts */
1335         ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1336         if (ret < 0) {
1337                 dev_err(&slave->dev,
1338                         "SDW_SCP_INTMASK1 write failed:%d\n", ret);
1339                 return ret;
1340         }
1341
1342         /* No need to continue if DP0 is not present */
1343         if (!slave->prop.dp0_prop)
1344                 return 0;
1345
1346         /* Enable DP0 interrupts */
1347         val = prop->dp0_prop->imp_def_interrupts;
1348         val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1349
1350         ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1351         if (ret < 0)
1352                 dev_err(&slave->dev,
1353                         "SDW_DP0_INTMASK read failed:%d\n", ret);
1354         return ret;
1355 }
1356
1357 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1358 {
1359         u8 clear, impl_int_mask;
1360         int status, status2, ret, count = 0;
1361
1362         status = sdw_read_no_pm(slave, SDW_DP0_INT);
1363         if (status < 0) {
1364                 dev_err(&slave->dev,
1365                         "SDW_DP0_INT read failed:%d\n", status);
1366                 return status;
1367         }
1368
1369         do {
1370                 clear = status & ~SDW_DP0_INTERRUPTS;
1371
1372                 if (status & SDW_DP0_INT_TEST_FAIL) {
1373                         dev_err(&slave->dev, "Test fail for port 0\n");
1374                         clear |= SDW_DP0_INT_TEST_FAIL;
1375                 }
1376
1377                 /*
1378                  * Assumption: PORT_READY interrupt will be received only for
1379                  * ports implementing Channel Prepare state machine (CP_SM)
1380                  */
1381
1382                 if (status & SDW_DP0_INT_PORT_READY) {
1383                         complete(&slave->port_ready[0]);
1384                         clear |= SDW_DP0_INT_PORT_READY;
1385                 }
1386
1387                 if (status & SDW_DP0_INT_BRA_FAILURE) {
1388                         dev_err(&slave->dev, "BRA failed\n");
1389                         clear |= SDW_DP0_INT_BRA_FAILURE;
1390                 }
1391
1392                 impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1393                         SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1394
1395                 if (status & impl_int_mask) {
1396                         clear |= impl_int_mask;
1397                         *slave_status = clear;
1398                 }
1399
1400                 /* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1401                 ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1402                 if (ret < 0) {
1403                         dev_err(&slave->dev,
1404                                 "SDW_DP0_INT write failed:%d\n", ret);
1405                         return ret;
1406                 }
1407
1408                 /* Read DP0 interrupt again */
1409                 status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1410                 if (status2 < 0) {
1411                         dev_err(&slave->dev,
1412                                 "SDW_DP0_INT read failed:%d\n", status2);
1413                         return status2;
1414                 }
1415                 /* filter to limit loop to interrupts identified in the first status read */
1416                 status &= status2;
1417
1418                 count++;
1419
1420                 /* we can get alerts while processing so keep retrying */
1421         } while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1422
1423         if (count == SDW_READ_INTR_CLEAR_RETRY)
1424                 dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
1425
1426         return ret;
1427 }
1428
1429 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1430                                      int port, u8 *slave_status)
1431 {
1432         u8 clear, impl_int_mask;
1433         int status, status2, ret, count = 0;
1434         u32 addr;
1435
1436         if (port == 0)
1437                 return sdw_handle_dp0_interrupt(slave, slave_status);
1438
1439         addr = SDW_DPN_INT(port);
1440         status = sdw_read_no_pm(slave, addr);
1441         if (status < 0) {
1442                 dev_err(&slave->dev,
1443                         "SDW_DPN_INT read failed:%d\n", status);
1444
1445                 return status;
1446         }
1447
1448         do {
1449                 clear = status & ~SDW_DPN_INTERRUPTS;
1450
1451                 if (status & SDW_DPN_INT_TEST_FAIL) {
1452                         dev_err(&slave->dev, "Test fail for port:%d\n", port);
1453                         clear |= SDW_DPN_INT_TEST_FAIL;
1454                 }
1455
1456                 /*
1457                  * Assumption: PORT_READY interrupt will be received only
1458                  * for ports implementing CP_SM.
1459                  */
1460                 if (status & SDW_DPN_INT_PORT_READY) {
1461                         complete(&slave->port_ready[port]);
1462                         clear |= SDW_DPN_INT_PORT_READY;
1463                 }
1464
1465                 impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1466                         SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1467
1468                 if (status & impl_int_mask) {
1469                         clear |= impl_int_mask;
1470                         *slave_status = clear;
1471                 }
1472
1473                 /* clear the interrupt but don't touch reserved fields */
1474                 ret = sdw_write_no_pm(slave, addr, clear);
1475                 if (ret < 0) {
1476                         dev_err(&slave->dev,
1477                                 "SDW_DPN_INT write failed:%d\n", ret);
1478                         return ret;
1479                 }
1480
1481                 /* Read DPN interrupt again */
1482                 status2 = sdw_read_no_pm(slave, addr);
1483                 if (status2 < 0) {
1484                         dev_err(&slave->dev,
1485                                 "SDW_DPN_INT read failed:%d\n", status2);
1486                         return status2;
1487                 }
1488                 /* filter to limit loop to interrupts identified in the first status read */
1489                 status &= status2;
1490
1491                 count++;
1492
1493                 /* we can get alerts while processing so keep retrying */
1494         } while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1495
1496         if (count == SDW_READ_INTR_CLEAR_RETRY)
1497                 dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1498
1499         return ret;
1500 }
1501
1502 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1503 {
1504         struct sdw_slave_intr_status slave_intr;
1505         u8 clear = 0, bit, port_status[15] = {0};
1506         int port_num, stat, ret, count = 0;
1507         unsigned long port;
1508         bool slave_notify;
1509         u8 sdca_cascade = 0;
1510         u8 buf, buf2[2], _buf, _buf2[2];
1511         bool parity_check;
1512         bool parity_quirk;
1513
1514         sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1515
1516         ret = pm_runtime_get_sync(&slave->dev);
1517         if (ret < 0 && ret != -EACCES) {
1518                 dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1519                 pm_runtime_put_noidle(&slave->dev);
1520                 return ret;
1521         }
1522
1523         /* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1524         ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1525         if (ret < 0) {
1526                 dev_err(&slave->dev,
1527                         "SDW_SCP_INT1 read failed:%d\n", ret);
1528                 goto io_err;
1529         }
1530         buf = ret;
1531
1532         ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1533         if (ret < 0) {
1534                 dev_err(&slave->dev,
1535                         "SDW_SCP_INT2/3 read failed:%d\n", ret);
1536                 goto io_err;
1537         }
1538
1539         if (slave->prop.is_sdca) {
1540                 ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1541                 if (ret < 0) {
1542                         dev_err(&slave->dev,
1543                                 "SDW_DP0_INT read failed:%d\n", ret);
1544                         goto io_err;
1545                 }
1546                 sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1547         }
1548
1549         do {
1550                 slave_notify = false;
1551
1552                 /*
1553                  * Check parity, bus clash and Slave (impl defined)
1554                  * interrupt
1555                  */
1556                 if (buf & SDW_SCP_INT1_PARITY) {
1557                         parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1558                         parity_quirk = !slave->first_interrupt_done &&
1559                                 (slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1560
1561                         if (parity_check && !parity_quirk)
1562                                 dev_err(&slave->dev, "Parity error detected\n");
1563                         clear |= SDW_SCP_INT1_PARITY;
1564                 }
1565
1566                 if (buf & SDW_SCP_INT1_BUS_CLASH) {
1567                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1568                                 dev_err(&slave->dev, "Bus clash detected\n");
1569                         clear |= SDW_SCP_INT1_BUS_CLASH;
1570                 }
1571
1572                 /*
1573                  * When bus clash or parity errors are detected, such errors
1574                  * are unlikely to be recoverable errors.
1575                  * TODO: In such scenario, reset bus. Make this configurable
1576                  * via sysfs property with bus reset being the default.
1577                  */
1578
1579                 if (buf & SDW_SCP_INT1_IMPL_DEF) {
1580                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1581                                 dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1582                                 slave_notify = true;
1583                         }
1584                         clear |= SDW_SCP_INT1_IMPL_DEF;
1585                 }
1586
1587                 /* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1588                 if (sdca_cascade)
1589                         slave_notify = true;
1590
1591                 /* Check port 0 - 3 interrupts */
1592                 port = buf & SDW_SCP_INT1_PORT0_3;
1593
1594                 /* To get port number corresponding to bits, shift it */
1595                 port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1596                 for_each_set_bit(bit, &port, 8) {
1597                         sdw_handle_port_interrupt(slave, bit,
1598                                                   &port_status[bit]);
1599                 }
1600
1601                 /* Check if cascade 2 interrupt is present */
1602                 if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1603                         port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1604                         for_each_set_bit(bit, &port, 8) {
1605                                 /* scp2 ports start from 4 */
1606                                 port_num = bit + 3;
1607                                 sdw_handle_port_interrupt(slave,
1608                                                 port_num,
1609                                                 &port_status[port_num]);
1610                         }
1611                 }
1612
1613                 /* now check last cascade */
1614                 if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1615                         port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1616                         for_each_set_bit(bit, &port, 8) {
1617                                 /* scp3 ports start from 11 */
1618                                 port_num = bit + 10;
1619                                 sdw_handle_port_interrupt(slave,
1620                                                 port_num,
1621                                                 &port_status[port_num]);
1622                         }
1623                 }
1624
1625                 /* Update the Slave driver */
1626                 if (slave_notify) {
1627                         mutex_lock(&slave->sdw_dev_lock);
1628
1629                         if (slave->probed) {
1630                                 struct device *dev = &slave->dev;
1631                                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1632
1633                                 if (drv->ops && drv->ops->interrupt_callback) {
1634                                         slave_intr.sdca_cascade = sdca_cascade;
1635                                         slave_intr.control_port = clear;
1636                                         memcpy(slave_intr.port, &port_status,
1637                                                sizeof(slave_intr.port));
1638
1639                                         drv->ops->interrupt_callback(slave, &slave_intr);
1640                                 }
1641                         }
1642
1643                         mutex_unlock(&slave->sdw_dev_lock);
1644                 }
1645
1646                 /* Ack interrupt */
1647                 ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1648                 if (ret < 0) {
1649                         dev_err(&slave->dev,
1650                                 "SDW_SCP_INT1 write failed:%d\n", ret);
1651                         goto io_err;
1652                 }
1653
1654                 /* at this point all initial interrupt sources were handled */
1655                 slave->first_interrupt_done = true;
1656
1657                 /*
1658                  * Read status again to ensure no new interrupts arrived
1659                  * while servicing interrupts.
1660                  */
1661                 ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1662                 if (ret < 0) {
1663                         dev_err(&slave->dev,
1664                                 "SDW_SCP_INT1 recheck read failed:%d\n", ret);
1665                         goto io_err;
1666                 }
1667                 _buf = ret;
1668
1669                 ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2);
1670                 if (ret < 0) {
1671                         dev_err(&slave->dev,
1672                                 "SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1673                         goto io_err;
1674                 }
1675
1676                 if (slave->prop.is_sdca) {
1677                         ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1678                         if (ret < 0) {
1679                                 dev_err(&slave->dev,
1680                                         "SDW_DP0_INT recheck read failed:%d\n", ret);
1681                                 goto io_err;
1682                         }
1683                         sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1684                 }
1685
1686                 /*
1687                  * Make sure no interrupts are pending, but filter to limit loop
1688                  * to interrupts identified in the first status read
1689                  */
1690                 buf &= _buf;
1691                 buf2[0] &= _buf2[0];
1692                 buf2[1] &= _buf2[1];
1693                 stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1694
1695                 /*
1696                  * Exit loop if Slave is continuously in ALERT state even
1697                  * after servicing the interrupt multiple times.
1698                  */
1699                 count++;
1700
1701                 /* we can get alerts while processing so keep retrying */
1702         } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1703
1704         if (count == SDW_READ_INTR_CLEAR_RETRY)
1705                 dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1706
1707 io_err:
1708         pm_runtime_mark_last_busy(&slave->dev);
1709         pm_runtime_put_autosuspend(&slave->dev);
1710
1711         return ret;
1712 }
1713
1714 static int sdw_update_slave_status(struct sdw_slave *slave,
1715                                    enum sdw_slave_status status)
1716 {
1717         int ret = 0;
1718
1719         mutex_lock(&slave->sdw_dev_lock);
1720
1721         if (slave->probed) {
1722                 struct device *dev = &slave->dev;
1723                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1724
1725                 if (drv->ops && drv->ops->update_status)
1726                         ret = drv->ops->update_status(slave, status);
1727         }
1728
1729         mutex_unlock(&slave->sdw_dev_lock);
1730
1731         return ret;
1732 }
1733
1734 /**
1735  * sdw_handle_slave_status() - Handle Slave status
1736  * @bus: SDW bus instance
1737  * @status: Status for all Slave(s)
1738  */
1739 int sdw_handle_slave_status(struct sdw_bus *bus,
1740                             enum sdw_slave_status status[])
1741 {
1742         enum sdw_slave_status prev_status;
1743         struct sdw_slave *slave;
1744         bool attached_initializing;
1745         int i, ret = 0;
1746
1747         /* first check if any Slaves fell off the bus */
1748         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1749                 mutex_lock(&bus->bus_lock);
1750                 if (test_bit(i, bus->assigned) == false) {
1751                         mutex_unlock(&bus->bus_lock);
1752                         continue;
1753                 }
1754                 mutex_unlock(&bus->bus_lock);
1755
1756                 slave = sdw_get_slave(bus, i);
1757                 if (!slave)
1758                         continue;
1759
1760                 if (status[i] == SDW_SLAVE_UNATTACHED &&
1761                     slave->status != SDW_SLAVE_UNATTACHED)
1762                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1763         }
1764
1765         if (status[0] == SDW_SLAVE_ATTACHED) {
1766                 dev_dbg(bus->dev, "Slave attached, programming device number\n");
1767                 ret = sdw_program_device_num(bus);
1768                 if (ret < 0)
1769                         dev_err(bus->dev, "Slave attach failed: %d\n", ret);
1770                 /*
1771                  * programming a device number will have side effects,
1772                  * so we deal with other devices at a later time
1773                  */
1774                 return ret;
1775         }
1776
1777         /* Continue to check other slave statuses */
1778         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1779                 mutex_lock(&bus->bus_lock);
1780                 if (test_bit(i, bus->assigned) == false) {
1781                         mutex_unlock(&bus->bus_lock);
1782                         continue;
1783                 }
1784                 mutex_unlock(&bus->bus_lock);
1785
1786                 slave = sdw_get_slave(bus, i);
1787                 if (!slave)
1788                         continue;
1789
1790                 attached_initializing = false;
1791
1792                 switch (status[i]) {
1793                 case SDW_SLAVE_UNATTACHED:
1794                         if (slave->status == SDW_SLAVE_UNATTACHED)
1795                                 break;
1796
1797                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1798                         break;
1799
1800                 case SDW_SLAVE_ALERT:
1801                         ret = sdw_handle_slave_alerts(slave);
1802                         if (ret < 0)
1803                                 dev_err(&slave->dev,
1804                                         "Slave %d alert handling failed: %d\n",
1805                                         i, ret);
1806                         break;
1807
1808                 case SDW_SLAVE_ATTACHED:
1809                         if (slave->status == SDW_SLAVE_ATTACHED)
1810                                 break;
1811
1812                         prev_status = slave->status;
1813                         sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1814
1815                         if (prev_status == SDW_SLAVE_ALERT)
1816                                 break;
1817
1818                         attached_initializing = true;
1819
1820                         ret = sdw_initialize_slave(slave);
1821                         if (ret < 0)
1822                                 dev_err(&slave->dev,
1823                                         "Slave %d initialization failed: %d\n",
1824                                         i, ret);
1825
1826                         break;
1827
1828                 default:
1829                         dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1830                                 i, status[i]);
1831                         break;
1832                 }
1833
1834                 ret = sdw_update_slave_status(slave, status[i]);
1835                 if (ret < 0)
1836                         dev_err(&slave->dev,
1837                                 "Update Slave status failed:%d\n", ret);
1838                 if (attached_initializing) {
1839                         dev_dbg(&slave->dev,
1840                                 "%s: signaling initialization completion for Slave %d\n",
1841                                 __func__, slave->dev_num);
1842
1843                         complete(&slave->initialization_complete);
1844                 }
1845         }
1846
1847         return ret;
1848 }
1849 EXPORT_SYMBOL(sdw_handle_slave_status);
1850
1851 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1852 {
1853         struct sdw_slave *slave;
1854         int i;
1855
1856         /* Check all non-zero devices */
1857         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1858                 mutex_lock(&bus->bus_lock);
1859                 if (test_bit(i, bus->assigned) == false) {
1860                         mutex_unlock(&bus->bus_lock);
1861                         continue;
1862                 }
1863                 mutex_unlock(&bus->bus_lock);
1864
1865                 slave = sdw_get_slave(bus, i);
1866                 if (!slave)
1867                         continue;
1868
1869                 if (slave->status != SDW_SLAVE_UNATTACHED) {
1870                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1871                         slave->first_interrupt_done = false;
1872                         sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED);
1873                 }
1874
1875                 /* keep track of request, used in pm_runtime resume */
1876                 slave->unattach_request = request;
1877         }
1878 }
1879 EXPORT_SYMBOL(sdw_clear_slave_status);