drivers/soc/qcom/smp2p.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2015, Sony Mobile Communications AB.
   4  * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
   5  */
   6
   7 #include <linux/interrupt.h>
   8 #include <linux/list.h>
   9 #include <linux/io.h>
  10 #include <linux/of.h>
  11 #include <linux/irq.h>
  12 #include <linux/irqdomain.h>
  13 #include <linux/mailbox_client.h>
  14 #include <linux/mfd/syscon.h>
  15 #include <linux/module.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/pm_wakeirq.h>
  18 #include <linux/regmap.h>
  19 #include <linux/soc/qcom/smem.h>
  20 #include <linux/soc/qcom/smem_state.h>
  21 #include <linux/spinlock.h>
  22
  23 /*
  24  * The Shared Memory Point to Point (SMP2P) protocol facilitates communication
  25  * of a single 32-bit value between two processors.  Each value has a single
  26  * writer (the local side) and a single reader (the remote side). Values are
  27  * uniquely identified in the system by the directed edge (local processor ID
  28  * to remote processor ID) and a string identifier.
  29  *
  30  * Each processor is responsible for creating the outgoing SMEM items and each
  31  * item is writable by the local processor and readable by the remote
  32  * processor.  By using two separate SMEM items that are single-reader and
  33  * single-writer, SMP2P does not require any remote locking mechanisms.
  34  *
  35  * The driver uses the Linux GPIO and interrupt framework to expose a virtual
  36  * GPIO for each outbound entry and a virtual interrupt controller for each
  37  * inbound entry.
  38  */
  39
  40 #define SMP2P_MAX_ENTRY 16
  41 #define SMP2P_MAX_ENTRY_NAME 16
  42
  43 #define SMP2P_FEATURE_SSR_ACK 0x1
  44 #define SMP2P_FLAGS_RESTART_DONE_BIT 0
  45 #define SMP2P_FLAGS_RESTART_ACK_BIT 1
  46
  47 #define SMP2P_MAGIC 0x504d5324
  48 #define SMP2P_ALL_FEATURES      SMP2P_FEATURE_SSR_ACK
  49
  50 /**
  51  * struct smp2p_smem_item - in memory communication structure
  52  * @magic:              magic number
  53  * @version:            version - must be 1
  54  * @features:           features flag - currently unused
  55  * @local_pid:          processor id of sending end
  56  * @remote_pid:         processor id of receiving end
  57  * @total_entries:      number of entries - always SMP2P_MAX_ENTRY
  58  * @valid_entries:      number of allocated entries
  59  * @flags:
  60  * @entries:            individual communication entries
  61  *     @name:           name of the entry
  62  *     @value:          content of the entry
  63  */
  64 struct smp2p_smem_item {
  65         u32 magic;
  66         u8 version;
  67         unsigned features:24;
  68         u16 local_pid;
  69         u16 remote_pid;
  70         u16 total_entries;
  71         u16 valid_entries;
  72         u32 flags;
  73
  74         struct {
  75                 u8 name[SMP2P_MAX_ENTRY_NAME];
  76                 u32 value;
  77         } entries[SMP2P_MAX_ENTRY];
  78 } __packed;
  79
  80 /**
  81  * struct smp2p_entry - driver context matching one entry
  82  * @node:       list entry to keep track of allocated entries
  83  * @smp2p:      reference to the device driver context
  84  * @name:       name of the entry, to match against smp2p_smem_item
  85  * @value:      pointer to smp2p_smem_item entry value
  86  * @last_value: last handled value
  87  * @domain:     irq_domain for inbound entries
  88  * @irq_enabled:bitmap to track enabled irq bits
  89  * @irq_rising: bitmap to mark irq bits for rising detection
  90  * @irq_falling:bitmap to mark irq bits for falling detection
  91  * @state:      smem state handle
  92  * @lock:       spinlock to protect read-modify-write of the value
  93  */
  94 struct smp2p_entry {
  95         struct list_head node;
  96         struct qcom_smp2p *smp2p;
  97
  98         const char *name;
  99         u32 *value;
 100         u32 last_value;
 101
 102         struct irq_domain *domain;
 103         DECLARE_BITMAP(irq_enabled, 32);
 104         DECLARE_BITMAP(irq_rising, 32);
 105         DECLARE_BITMAP(irq_falling, 32);
 106
 107         struct qcom_smem_state *state;
 108
 109         spinlock_t lock;
 110 };
 111
 112 #define SMP2P_INBOUND   0
 113 #define SMP2P_OUTBOUND  1
 114
 115 /**
 116  * struct qcom_smp2p - device driver context
 117  * @dev:        device driver handle
 118  * @in:         pointer to the inbound smem item
 119  * @out:        pointer to the outbound smem item
 120  * @smem_items: ids of the two smem items
 121  * @valid_entries: already scanned inbound entries
 122  * @local_pid:  processor id of the inbound edge
 123  * @remote_pid: processor id of the outbound edge
 124  * @ipc_regmap: regmap for the outbound ipc
 125  * @ipc_offset: offset within the regmap
 126  * @ipc_bit:    bit in regmap@offset to kick to signal remote processor
 127  * @mbox_client: mailbox client handle
 128  * @mbox_chan:  apcs ipc mailbox channel handle
 129  * @inbound:    list of inbound entries
 130  * @outbound:   list of outbound entries
 131  */
 132 struct qcom_smp2p {
 133         struct device *dev;
 134
 135         struct smp2p_smem_item *in;
 136         struct smp2p_smem_item *out;
 137
 138         unsigned smem_items[SMP2P_OUTBOUND + 1];
 139
 140         unsigned valid_entries;
 141
 142         bool ssr_ack_enabled;
 143         bool ssr_ack;
 144         bool negotiation_done;
 145
 146         unsigned local_pid;
 147         unsigned remote_pid;
 148
 149         struct regmap *ipc_regmap;
 150         int ipc_offset;
 151         int ipc_bit;
 152
 153         struct mbox_client mbox_client;
 154         struct mbox_chan *mbox_chan;
 155
 156         struct list_head inbound;
 157         struct list_head outbound;
 158 };
 159
 160 static void qcom_smp2p_kick(struct qcom_smp2p *smp2p)
 161 {
 162         /* Make sure any updated data is written before the kick */
 163         wmb();
 164
 165         if (smp2p->mbox_chan) {
 166                 mbox_send_message(smp2p->mbox_chan, NULL);
 167                 mbox_client_txdone(smp2p->mbox_chan, 0);
 168         } else {
 169                 regmap_write(smp2p->ipc_regmap, smp2p->ipc_offset, BIT(smp2p->ipc_bit));
 170         }
 171 }
 172
 173 static bool qcom_smp2p_check_ssr(struct qcom_smp2p *smp2p)
 174 {
 175         struct smp2p_smem_item *in = smp2p->in;
 176         bool restart;
 177
 178         if (!smp2p->ssr_ack_enabled)
 179                 return false;
 180
 181         restart = in->flags & BIT(SMP2P_FLAGS_RESTART_DONE_BIT);
 182
 183         return restart != smp2p->ssr_ack;
 184 }
 185
 186 static void qcom_smp2p_do_ssr_ack(struct qcom_smp2p *smp2p)
 187 {
 188         struct smp2p_smem_item *out = smp2p->out;
 189         u32 val;
 190
 191         smp2p->ssr_ack = !smp2p->ssr_ack;
 192
 193         val = out->flags & ~BIT(SMP2P_FLAGS_RESTART_ACK_BIT);
 194         if (smp2p->ssr_ack)
 195                 val |= BIT(SMP2P_FLAGS_RESTART_ACK_BIT);
 196         out->flags = val;
 197
 198         qcom_smp2p_kick(smp2p);
 199 }
 200
 201 static void qcom_smp2p_negotiate(struct qcom_smp2p *smp2p)
 202 {
 203         struct smp2p_smem_item *out = smp2p->out;
 204         struct smp2p_smem_item *in = smp2p->in;
 205
 206         if (in->version == out->version) {
 207                 out->features &= in->features;
 208
 209                 if (out->features & SMP2P_FEATURE_SSR_ACK)
 210                         smp2p->ssr_ack_enabled = true;
 211
 212                 smp2p->negotiation_done = true;
 213         }
 214 }
 215
 216 static void qcom_smp2p_notify_in(struct qcom_smp2p *smp2p)
 217 {
 218         struct smp2p_smem_item *in;
 219         struct smp2p_entry *entry;
 220         int irq_pin;
 221         u32 status;
 222         char buf[SMP2P_MAX_ENTRY_NAME];
 223         u32 val;
 224         int i;
 225
 226         in = smp2p->in;
 227
 228         /* Match newly created entries */
 229         for (i = smp2p->valid_entries; i < in->valid_entries; i++) {
 230                 list_for_each_entry(entry, &smp2p->inbound, node) {
 231                         memcpy(buf, in->entries[i].name, sizeof(buf));
 232                         if (!strcmp(buf, entry->name)) {
 233                                 entry->value = &in->entries[i].value;
 234                                 break;
 235                         }
 236                 }
 237         }
 238         smp2p->valid_entries = i;
 239
 240         /* Fire interrupts based on any value changes */
 241         list_for_each_entry(entry, &smp2p->inbound, node) {
 242                 /* Ignore entries not yet allocated by the remote side */
 243                 if (!entry->value)
 244                         continue;
 245
 246                 val = readl(entry->value);
 247
 248                 status = val ^ entry->last_value;
 249                 entry->last_value = val;
 250
 251                 /* No changes of this entry? */
 252                 if (!status)
 253                         continue;
 254
 255                 for_each_set_bit(i, entry->irq_enabled, 32) {
 256                         if (!(status & BIT(i)))
 257                                 continue;
 258
 259                         if ((val & BIT(i) && test_bit(i, entry->irq_rising)) ||
 260                             (!(val & BIT(i)) && test_bit(i, entry->irq_falling))) {
 261                                 irq_pin = irq_find_mapping(entry->domain, i);
 262                                 handle_nested_irq(irq_pin);
 263                         }
 264                 }
 265         }
 266 }
 267
 268 /**
 269  * qcom_smp2p_intr() - interrupt handler for incoming notifications
 270  * @irq:        unused
 271  * @data:       smp2p driver context
 272  *
 273  * Handle notifications from the remote side to handle newly allocated entries
 274  * or any changes to the state bits of existing entries.
 275  */
 276 static irqreturn_t qcom_smp2p_intr(int irq, void *data)
 277 {
 278         struct smp2p_smem_item *in;
 279         struct qcom_smp2p *smp2p = data;
 280         unsigned int smem_id = smp2p->smem_items[SMP2P_INBOUND];
 281         unsigned int pid = smp2p->remote_pid;
 282         bool ack_restart;
 283         size_t size;
 284
 285         in = smp2p->in;
 286
 287         /* Acquire smem item, if not already found */
 288         if (!in) {
 289                 in = qcom_smem_get(pid, smem_id, &size);
 290                 if (IS_ERR(in)) {
 291                         dev_err(smp2p->dev,
 292                                 "Unable to acquire remote smp2p item\n");
 293                         goto out;
 294                 }
 295
 296                 smp2p->in = in;
 297         }
 298
 299         if (!smp2p->negotiation_done)
 300                 qcom_smp2p_negotiate(smp2p);
 301
 302         if (smp2p->negotiation_done) {
 303                 ack_restart = qcom_smp2p_check_ssr(smp2p);
 304                 qcom_smp2p_notify_in(smp2p);
 305
 306                 if (ack_restart)
 307                         qcom_smp2p_do_ssr_ack(smp2p);
 308         }
 309
 310 out:
 311         return IRQ_HANDLED;
 312 }
 313
 314 static void smp2p_mask_irq(struct irq_data *irqd)
 315 {
 316         struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
 317         irq_hw_number_t irq = irqd_to_hwirq(irqd);
 318
 319         clear_bit(irq, entry->irq_enabled);
 320 }
 321
 322 static void smp2p_unmask_irq(struct irq_data *irqd)
 323 {
 324         struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
 325         irq_hw_number_t irq = irqd_to_hwirq(irqd);
 326
 327         set_bit(irq, entry->irq_enabled);
 328 }
 329
 330 static int smp2p_set_irq_type(struct irq_data *irqd, unsigned int type)
 331 {
 332         struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
 333         irq_hw_number_t irq = irqd_to_hwirq(irqd);
 334
 335         if (!(type & IRQ_TYPE_EDGE_BOTH))
 336                 return -EINVAL;
 337
 338         if (type & IRQ_TYPE_EDGE_RISING)
 339                 set_bit(irq, entry->irq_rising);
 340         else
 341                 clear_bit(irq, entry->irq_rising);
 342
 343         if (type & IRQ_TYPE_EDGE_FALLING)
 344                 set_bit(irq, entry->irq_falling);
 345         else
 346                 clear_bit(irq, entry->irq_falling);
 347
 348         return 0;
 349 }
 350
 351 static struct irq_chip smp2p_irq_chip = {
 352         .name           = "smp2p",
 353         .irq_mask       = smp2p_mask_irq,
 354         .irq_unmask     = smp2p_unmask_irq,
 355         .irq_set_type   = smp2p_set_irq_type,
 356 };
 357
 358 static int smp2p_irq_map(struct irq_domain *d,
 359                          unsigned int irq,
 360                          irq_hw_number_t hw)
 361 {
 362         struct smp2p_entry *entry = d->host_data;
 363
 364         irq_set_chip_and_handler(irq, &smp2p_irq_chip, handle_level_irq);
 365         irq_set_chip_data(irq, entry);
 366         irq_set_nested_thread(irq, 1);
 367         irq_set_noprobe(irq);
 368
 369         return 0;
 370 }
 371
 372 static const struct irq_domain_ops smp2p_irq_ops = {
 373         .map = smp2p_irq_map,
 374         .xlate = irq_domain_xlate_twocell,
 375 };
 376
 377 static int qcom_smp2p_inbound_entry(struct qcom_smp2p *smp2p,
 378                                     struct smp2p_entry *entry,
 379                                     struct device_node *node)
 380 {
 381         entry->domain = irq_domain_add_linear(node, 32, &smp2p_irq_ops, entry);
 382         if (!entry->domain) {
 383                 dev_err(smp2p->dev, "failed to add irq_domain\n");
 384                 return -ENOMEM;
 385         }
 386
 387         return 0;
 388 }
 389
 390 static int smp2p_update_bits(void *data, u32 mask, u32 value)
 391 {
 392         struct smp2p_entry *entry = data;
 393         unsigned long flags;
 394         u32 orig;
 395         u32 val;
 396
 397         spin_lock_irqsave(&entry->lock, flags);
 398         val = orig = readl(entry->value);
 399         val &= ~mask;
 400         val |= value;
 401         writel(val, entry->value);
 402         spin_unlock_irqrestore(&entry->lock, flags);
 403
 404         if (val != orig)
 405                 qcom_smp2p_kick(entry->smp2p);
 406
 407         return 0;
 408 }
 409
 410 static const struct qcom_smem_state_ops smp2p_state_ops = {
 411         .update_bits = smp2p_update_bits,
 412 };
 413
 414 static int qcom_smp2p_outbound_entry(struct qcom_smp2p *smp2p,
 415                                      struct smp2p_entry *entry,
 416                                      struct device_node *node)
 417 {
 418         struct smp2p_smem_item *out = smp2p->out;
 419         char buf[SMP2P_MAX_ENTRY_NAME] = {};
 420
 421         /* Allocate an entry from the smem item */
 422         strlcpy(buf, entry->name, SMP2P_MAX_ENTRY_NAME);
 423         memcpy(out->entries[out->valid_entries].name, buf, SMP2P_MAX_ENTRY_NAME);
 424
 425         /* Make the logical entry reference the physical value */
 426         entry->value = &out->entries[out->valid_entries].value;
 427
 428         out->valid_entries++;
 429
 430         entry->state = qcom_smem_state_register(node, &smp2p_state_ops, entry);
 431         if (IS_ERR(entry->state)) {
 432                 dev_err(smp2p->dev, "failed to register qcom_smem_state\n");
 433                 return PTR_ERR(entry->state);
 434         }
 435
 436         return 0;
 437 }
 438
 439 static int qcom_smp2p_alloc_outbound_item(struct qcom_smp2p *smp2p)
 440 {
 441         struct smp2p_smem_item *out;
 442         unsigned smem_id = smp2p->smem_items[SMP2P_OUTBOUND];
 443         unsigned pid = smp2p->remote_pid;
 444         int ret;
 445
 446         ret = qcom_smem_alloc(pid, smem_id, sizeof(*out));
 447         if (ret < 0 && ret != -EEXIST) {
 448                 if (ret != -EPROBE_DEFER)
 449                         dev_err(smp2p->dev,
 450                                 "unable to allocate local smp2p item\n");
 451                 return ret;
 452         }
 453
 454         out = qcom_smem_get(pid, smem_id, NULL);
 455         if (IS_ERR(out)) {
 456                 dev_err(smp2p->dev, "Unable to acquire local smp2p item\n");
 457                 return PTR_ERR(out);
 458         }
 459
 460         memset(out, 0, sizeof(*out));
 461         out->magic = SMP2P_MAGIC;
 462         out->local_pid = smp2p->local_pid;
 463         out->remote_pid = smp2p->remote_pid;
 464         out->total_entries = SMP2P_MAX_ENTRY;
 465         out->valid_entries = 0;
 466         out->features = SMP2P_ALL_FEATURES;
 467
 468         /*
 469          * Make sure the rest of the header is written before we validate the
 470          * item by writing a valid version number.
 471          */
 472         wmb();
 473         out->version = 1;
 474
 475         qcom_smp2p_kick(smp2p);
 476
 477         smp2p->out = out;
 478
 479         return 0;
 480 }
 481
 482 static int smp2p_parse_ipc(struct qcom_smp2p *smp2p)
 483 {
 484         struct device_node *syscon;
 485         struct device *dev = smp2p->dev;
 486         const char *key;
 487         int ret;
 488
 489         syscon = of_parse_phandle(dev->of_node, "qcom,ipc", 0);
 490         if (!syscon) {
 491                 dev_err(dev, "no qcom,ipc node\n");
 492                 return -ENODEV;
 493         }
 494
 495         smp2p->ipc_regmap = syscon_node_to_regmap(syscon);
 496         of_node_put(syscon);
 497         if (IS_ERR(smp2p->ipc_regmap))
 498                 return PTR_ERR(smp2p->ipc_regmap);
 499
 500         key = "qcom,ipc";
 501         ret = of_property_read_u32_index(dev->of_node, key, 1, &smp2p->ipc_offset);
 502         if (ret < 0) {
 503                 dev_err(dev, "no offset in %s\n", key);
 504                 return -EINVAL;
 505         }
 506
 507         ret = of_property_read_u32_index(dev->of_node, key, 2, &smp2p->ipc_bit);
 508         if (ret < 0) {
 509                 dev_err(dev, "no bit in %s\n", key);
 510                 return -EINVAL;
 511         }
 512
 513         return 0;
 514 }
 515
 516 static int qcom_smp2p_probe(struct platform_device *pdev)
 517 {
 518         struct smp2p_entry *entry;
 519         struct device_node *node;
 520         struct qcom_smp2p *smp2p;
 521         const char *key;
 522         int irq;
 523         int ret;
 524
 525         smp2p = devm_kzalloc(&pdev->dev, sizeof(*smp2p), GFP_KERNEL);
 526         if (!smp2p)
 527                 return -ENOMEM;
 528
 529         smp2p->dev = &pdev->dev;
 530         INIT_LIST_HEAD(&smp2p->inbound);
 531         INIT_LIST_HEAD(&smp2p->outbound);
 532
 533         platform_set_drvdata(pdev, smp2p);
 534
 535         key = "qcom,smem";
 536         ret = of_property_read_u32_array(pdev->dev.of_node, key,
 537                                          smp2p->smem_items, 2);
 538         if (ret)
 539                 return ret;
 540
 541         key = "qcom,local-pid";
 542         ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->local_pid);
 543         if (ret)
 544                 goto report_read_failure;
 545
 546         key = "qcom,remote-pid";
 547         ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->remote_pid);
 548         if (ret)
 549                 goto report_read_failure;
 550
 551         irq = platform_get_irq(pdev, 0);
 552         if (irq < 0)
 553                 return irq;
 554
 555         smp2p->mbox_client.dev = &pdev->dev;
 556         smp2p->mbox_client.knows_txdone = true;
 557         smp2p->mbox_chan = mbox_request_channel(&smp2p->mbox_client, 0);
 558         if (IS_ERR(smp2p->mbox_chan)) {
 559                 if (PTR_ERR(smp2p->mbox_chan) != -ENODEV)
 560                         return PTR_ERR(smp2p->mbox_chan);
 561
 562                 smp2p->mbox_chan = NULL;
 563
 564                 ret = smp2p_parse_ipc(smp2p);
 565                 if (ret)
 566                         return ret;
 567         }
 568
 569         ret = qcom_smp2p_alloc_outbound_item(smp2p);
 570         if (ret < 0)
 571                 goto release_mbox;
 572
 573         for_each_available_child_of_node(pdev->dev.of_node, node) {
 574                 entry = devm_kzalloc(&pdev->dev, sizeof(*entry), GFP_KERNEL);
 575                 if (!entry) {
 576                         ret = -ENOMEM;
 577                         of_node_put(node);
 578                         goto unwind_interfaces;
 579                 }
 580
 581                 entry->smp2p = smp2p;
 582                 spin_lock_init(&entry->lock);
 583
 584                 ret = of_property_read_string(node, "qcom,entry-name", &entry->name);
 585                 if (ret < 0) {
 586                         of_node_put(node);
 587                         goto unwind_interfaces;
 588                 }
 589
 590                 if (of_property_read_bool(node, "interrupt-controller")) {
 591                         ret = qcom_smp2p_inbound_entry(smp2p, entry, node);
 592                         if (ret < 0) {
 593                                 of_node_put(node);
 594                                 goto unwind_interfaces;
 595                         }
 596
 597                         list_add(&entry->node, &smp2p->inbound);
 598                 } else  {
 599                         ret = qcom_smp2p_outbound_entry(smp2p, entry, node);
 600                         if (ret < 0) {
 601                                 of_node_put(node);
 602                                 goto unwind_interfaces;
 603                         }
 604
 605                         list_add(&entry->node, &smp2p->outbound);
 606                 }
 607         }
 608
 609         /* Kick the outgoing edge after allocating entries */
 610         qcom_smp2p_kick(smp2p);
 611
 612         ret = devm_request_threaded_irq(&pdev->dev, irq,
 613                                         NULL, qcom_smp2p_intr,
 614                                         IRQF_ONESHOT,
 615                                         "smp2p", (void *)smp2p);
 616         if (ret) {
 617                 dev_err(&pdev->dev, "failed to request interrupt\n");
 618                 goto unwind_interfaces;
 619         }
 620
 621         /*
 622          * Treat smp2p interrupt as wakeup source, but keep it disabled
 623          * by default. User space can decide enabling it depending on its
 624          * use cases. For example if remoteproc crashes and device wants
 625          * to handle it immediatedly (e.g. to not miss phone calls) it can
 626          * enable wakeup source from user space, while other devices which
 627          * do not have proper autosleep feature may want to handle it with
 628          * other wakeup events (e.g. Power button) instead waking up immediately.
 629          */
 630         device_set_wakeup_capable(&pdev->dev, true);
 631
 632         ret = dev_pm_set_wake_irq(&pdev->dev, irq);
 633         if (ret)
 634                 goto set_wake_irq_fail;
 635
 636         return 0;
 637
 638 set_wake_irq_fail:
 639         dev_pm_clear_wake_irq(&pdev->dev);
 640
 641 unwind_interfaces:
 642         list_for_each_entry(entry, &smp2p->inbound, node)
 643                 irq_domain_remove(entry->domain);
 644
 645         list_for_each_entry(entry, &smp2p->outbound, node)
 646                 qcom_smem_state_unregister(entry->state);
 647
 648         smp2p->out->valid_entries = 0;
 649
 650 release_mbox:
 651         mbox_free_channel(smp2p->mbox_chan);
 652
 653         return ret;
 654
 655 report_read_failure:
 656         dev_err(&pdev->dev, "failed to read %s\n", key);
 657         return -EINVAL;
 658 }
 659
 660 static int qcom_smp2p_remove(struct platform_device *pdev)
 661 {
 662         struct qcom_smp2p *smp2p = platform_get_drvdata(pdev);
 663         struct smp2p_entry *entry;
 664
 665         dev_pm_clear_wake_irq(&pdev->dev);
 666
 667         list_for_each_entry(entry, &smp2p->inbound, node)
 668                 irq_domain_remove(entry->domain);
 669
 670         list_for_each_entry(entry, &smp2p->outbound, node)
 671                 qcom_smem_state_unregister(entry->state);
 672
 673         mbox_free_channel(smp2p->mbox_chan);
 674
 675         smp2p->out->valid_entries = 0;
 676
 677         return 0;
 678 }
 679
 680 static const struct of_device_id qcom_smp2p_of_match[] = {
 681         { .compatible = "qcom,smp2p" },
 682         {}
 683 };
 684 MODULE_DEVICE_TABLE(of, qcom_smp2p_of_match);
 685
 686 static struct platform_driver qcom_smp2p_driver = {
 687         .probe = qcom_smp2p_probe,
 688         .remove = qcom_smp2p_remove,
 689         .driver  = {
 690                 .name  = "qcom_smp2p",
 691                 .of_match_table = qcom_smp2p_of_match,
 692         },
 693 };
 694 module_platform_driver(qcom_smp2p_driver);
 695
 696 MODULE_DESCRIPTION("Qualcomm Shared Memory Point to Point driver");
 697 MODULE_LICENSE("GPL v2");