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/seq_file.h>
  20 #include <linux/soc/qcom/smem.h>
  21 #include <linux/soc/qcom/smem_state.h>
  22 #include <linux/spinlock.h>
  23
  24 /*
  25  * The Shared Memory Point to Point (SMP2P) protocol facilitates communication
  26  * of a single 32-bit value between two processors.  Each value has a single
  27  * writer (the local side) and a single reader (the remote side). Values are
  28  * uniquely identified in the system by the directed edge (local processor ID
  29  * to remote processor ID) and a string identifier.
  30  *
  31  * Each processor is responsible for creating the outgoing SMEM items and each
  32  * item is writable by the local processor and readable by the remote
  33  * processor.  By using two separate SMEM items that are single-reader and
  34  * single-writer, SMP2P does not require any remote locking mechanisms.
  35  *
  36  * The driver uses the Linux GPIO and interrupt framework to expose a virtual
  37  * GPIO for each outbound entry and a virtual interrupt controller for each
  38  * inbound entry.
  39  */
  40
  41 #define SMP2P_MAX_ENTRY 16
  42 #define SMP2P_MAX_ENTRY_NAME 16
  43
  44 #define SMP2P_FEATURE_SSR_ACK 0x1
  45 #define SMP2P_FLAGS_RESTART_DONE_BIT 0
  46 #define SMP2P_FLAGS_RESTART_ACK_BIT 1
  47
  48 #define SMP2P_MAGIC 0x504d5324
  49 #define SMP2P_ALL_FEATURES      SMP2P_FEATURE_SSR_ACK
  50
  51 /**
  52  * struct smp2p_smem_item - in memory communication structure
  53  * @magic:              magic number
  54  * @version:            version - must be 1
  55  * @features:           features flag - currently unused
  56  * @local_pid:          processor id of sending end
  57  * @remote_pid:         processor id of receiving end
  58  * @total_entries:      number of entries - always SMP2P_MAX_ENTRY
  59  * @valid_entries:      number of allocated entries
  60  * @flags:
  61  * @entries:            individual communication entries
  62  * @entries.name:       name of the entry
  63  * @entries.value:      content of the entry
  64  */
  65 struct smp2p_smem_item {
  66         u32 magic;
  67         u8 version;
  68         unsigned features:24;
  69         u16 local_pid;
  70         u16 remote_pid;
  71         u16 total_entries;
  72         u16 valid_entries;
  73         u32 flags;
  74
  75         struct {
  76                 u8 name[SMP2P_MAX_ENTRY_NAME];
  77                 u32 value;
  78         } entries[SMP2P_MAX_ENTRY];
  79 } __packed;
  80
  81 /**
  82  * struct smp2p_entry - driver context matching one entry
  83  * @node:       list entry to keep track of allocated entries
  84  * @smp2p:      reference to the device driver context
  85  * @name:       name of the entry, to match against smp2p_smem_item
  86  * @value:      pointer to smp2p_smem_item entry value
  87  * @last_value: last handled value
  88  * @domain:     irq_domain for inbound entries
  89  * @irq_enabled:bitmap to track enabled irq bits
  90  * @irq_rising: bitmap to mark irq bits for rising detection
  91  * @irq_falling:bitmap to mark irq bits for falling detection
  92  * @state:      smem state handle
  93  * @lock:       spinlock to protect read-modify-write of the value
  94  */
  95 struct smp2p_entry {
  96         struct list_head node;
  97         struct qcom_smp2p *smp2p;
  98
  99         const char *name;
 100         u32 *value;
 101         u32 last_value;
 102
 103         struct irq_domain *domain;
 104         DECLARE_BITMAP(irq_enabled, 32);
 105         DECLARE_BITMAP(irq_rising, 32);
 106         DECLARE_BITMAP(irq_falling, 32);
 107
 108         struct qcom_smem_state *state;
 109
 110         spinlock_t lock;
 111 };
 112
 113 #define SMP2P_INBOUND   0
 114 #define SMP2P_OUTBOUND  1
 115
 116 /**
 117  * struct qcom_smp2p - device driver context
 118  * @dev:        device driver handle
 119  * @in:         pointer to the inbound smem item
 120  * @out:        pointer to the outbound smem item
 121  * @smem_items: ids of the two smem items
 122  * @valid_entries: already scanned inbound entries
 123  * @ssr_ack_enabled: SMP2P_FEATURE_SSR_ACK feature is supported and was enabled
 124  * @ssr_ack: current cached state of the local ack bit
 125  * @negotiation_done: whether negotiating finished
 126  * @local_pid:  processor id of the inbound edge
 127  * @remote_pid: processor id of the outbound edge
 128  * @ipc_regmap: regmap for the outbound ipc
 129  * @ipc_offset: offset within the regmap
 130  * @ipc_bit:    bit in regmap@offset to kick to signal remote processor
 131  * @mbox_client: mailbox client handle
 132  * @mbox_chan:  apcs ipc mailbox channel handle
 133  * @inbound:    list of inbound entries
 134  * @outbound:   list of outbound entries
 135  */
 136 struct qcom_smp2p {
 137         struct device *dev;
 138
 139         struct smp2p_smem_item *in;
 140         struct smp2p_smem_item *out;
 141
 142         unsigned smem_items[SMP2P_OUTBOUND + 1];
 143
 144         unsigned valid_entries;
 145
 146         bool ssr_ack_enabled;
 147         bool ssr_ack;
 148         bool negotiation_done;
 149
 150         unsigned local_pid;
 151         unsigned remote_pid;
 152
 153         struct regmap *ipc_regmap;
 154         int ipc_offset;
 155         int ipc_bit;
 156
 157         struct mbox_client mbox_client;
 158         struct mbox_chan *mbox_chan;
 159
 160         struct list_head inbound;
 161         struct list_head outbound;
 162 };
 163
 164 static void qcom_smp2p_kick(struct qcom_smp2p *smp2p)
 165 {
 166         /* Make sure any updated data is written before the kick */
 167         wmb();
 168
 169         if (smp2p->mbox_chan) {
 170                 mbox_send_message(smp2p->mbox_chan, NULL);
 171                 mbox_client_txdone(smp2p->mbox_chan, 0);
 172         } else {
 173                 regmap_write(smp2p->ipc_regmap, smp2p->ipc_offset, BIT(smp2p->ipc_bit));
 174         }
 175 }
 176
 177 static bool qcom_smp2p_check_ssr(struct qcom_smp2p *smp2p)
 178 {
 179         struct smp2p_smem_item *in = smp2p->in;
 180         bool restart;
 181
 182         if (!smp2p->ssr_ack_enabled)
 183                 return false;
 184
 185         restart = in->flags & BIT(SMP2P_FLAGS_RESTART_DONE_BIT);
 186
 187         return restart != smp2p->ssr_ack;
 188 }
 189
 190 static void qcom_smp2p_do_ssr_ack(struct qcom_smp2p *smp2p)
 191 {
 192         struct smp2p_smem_item *out = smp2p->out;
 193         u32 val;
 194
 195         smp2p->ssr_ack = !smp2p->ssr_ack;
 196
 197         val = out->flags & ~BIT(SMP2P_FLAGS_RESTART_ACK_BIT);
 198         if (smp2p->ssr_ack)
 199                 val |= BIT(SMP2P_FLAGS_RESTART_ACK_BIT);
 200         out->flags = val;
 201
 202         qcom_smp2p_kick(smp2p);
 203 }
 204
 205 static void qcom_smp2p_negotiate(struct qcom_smp2p *smp2p)
 206 {
 207         struct smp2p_smem_item *out = smp2p->out;
 208         struct smp2p_smem_item *in = smp2p->in;
 209
 210         if (in->version == out->version) {
 211                 out->features &= in->features;
 212
 213                 if (out->features & SMP2P_FEATURE_SSR_ACK)
 214                         smp2p->ssr_ack_enabled = true;
 215
 216                 smp2p->negotiation_done = true;
 217         }
 218 }
 219
 220 static void qcom_smp2p_notify_in(struct qcom_smp2p *smp2p)
 221 {
 222         struct smp2p_smem_item *in;
 223         struct smp2p_entry *entry;
 224         int irq_pin;
 225         u32 status;
 226         char buf[SMP2P_MAX_ENTRY_NAME];
 227         u32 val;
 228         int i;
 229
 230         in = smp2p->in;
 231
 232         /* Match newly created entries */
 233         for (i = smp2p->valid_entries; i < in->valid_entries; i++) {
 234                 list_for_each_entry(entry, &smp2p->inbound, node) {
 235                         memcpy(buf, in->entries[i].name, sizeof(buf));
 236                         if (!strcmp(buf, entry->name)) {
 237                                 entry->value = &in->entries[i].value;
 238                                 break;
 239                         }
 240                 }
 241         }
 242         smp2p->valid_entries = i;
 243
 244         /* Fire interrupts based on any value changes */
 245         list_for_each_entry(entry, &smp2p->inbound, node) {
 246                 /* Ignore entries not yet allocated by the remote side */
 247                 if (!entry->value)
 248                         continue;
 249
 250                 val = readl(entry->value);
 251
 252                 status = val ^ entry->last_value;
 253                 entry->last_value = val;
 254
 255                 /* No changes of this entry? */
 256                 if (!status)
 257                         continue;
 258
 259                 for_each_set_bit(i, entry->irq_enabled, 32) {
 260                         if (!(status & BIT(i)))
 261                                 continue;
 262
 263                         if ((val & BIT(i) && test_bit(i, entry->irq_rising)) ||
 264                             (!(val & BIT(i)) && test_bit(i, entry->irq_falling))) {
 265                                 irq_pin = irq_find_mapping(entry->domain, i);
 266                                 handle_nested_irq(irq_pin);
 267                         }
 268                 }
 269         }
 270 }
 271
 272 /**
 273  * qcom_smp2p_intr() - interrupt handler for incoming notifications
 274  * @irq:        unused
 275  * @data:       smp2p driver context
 276  *
 277  * Handle notifications from the remote side to handle newly allocated entries
 278  * or any changes to the state bits of existing entries.
 279  *
 280  * Return: %IRQ_HANDLED
 281  */
 282 static irqreturn_t qcom_smp2p_intr(int irq, void *data)
 283 {
 284         struct smp2p_smem_item *in;
 285         struct qcom_smp2p *smp2p = data;
 286         unsigned int smem_id = smp2p->smem_items[SMP2P_INBOUND];
 287         unsigned int pid = smp2p->remote_pid;
 288         bool ack_restart;
 289         size_t size;
 290
 291         in = smp2p->in;
 292
 293         /* Acquire smem item, if not already found */
 294         if (!in) {
 295                 in = qcom_smem_get(pid, smem_id, &size);
 296                 if (IS_ERR(in)) {
 297                         dev_err(smp2p->dev,
 298                                 "Unable to acquire remote smp2p item\n");
 299                         goto out;
 300                 }
 301
 302                 smp2p->in = in;
 303         }
 304
 305         if (!smp2p->negotiation_done)
 306                 qcom_smp2p_negotiate(smp2p);
 307
 308         if (smp2p->negotiation_done) {
 309                 ack_restart = qcom_smp2p_check_ssr(smp2p);
 310                 qcom_smp2p_notify_in(smp2p);
 311
 312                 if (ack_restart)
 313                         qcom_smp2p_do_ssr_ack(smp2p);
 314         }
 315
 316 out:
 317         return IRQ_HANDLED;
 318 }
 319
 320 static void smp2p_mask_irq(struct irq_data *irqd)
 321 {
 322         struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
 323         irq_hw_number_t irq = irqd_to_hwirq(irqd);
 324
 325         clear_bit(irq, entry->irq_enabled);
 326 }
 327
 328 static void smp2p_unmask_irq(struct irq_data *irqd)
 329 {
 330         struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
 331         irq_hw_number_t irq = irqd_to_hwirq(irqd);
 332
 333         set_bit(irq, entry->irq_enabled);
 334 }
 335
 336 static int smp2p_set_irq_type(struct irq_data *irqd, unsigned int type)
 337 {
 338         struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
 339         irq_hw_number_t irq = irqd_to_hwirq(irqd);
 340
 341         if (!(type & IRQ_TYPE_EDGE_BOTH))
 342                 return -EINVAL;
 343
 344         if (type & IRQ_TYPE_EDGE_RISING)
 345                 set_bit(irq, entry->irq_rising);
 346         else
 347                 clear_bit(irq, entry->irq_rising);
 348
 349         if (type & IRQ_TYPE_EDGE_FALLING)
 350                 set_bit(irq, entry->irq_falling);
 351         else
 352                 clear_bit(irq, entry->irq_falling);
 353
 354         return 0;
 355 }
 356
 357 static void smp2p_irq_print_chip(struct irq_data *irqd, struct seq_file *p)
 358 {
 359         struct smp2p_entry *entry = irq_data_get_irq_chip_data(irqd);
 360
 361         seq_printf(p, " %8s", dev_name(entry->smp2p->dev));
 362 }
 363
 364 static struct irq_chip smp2p_irq_chip = {
 365         .name           = "smp2p",
 366         .irq_mask       = smp2p_mask_irq,
 367         .irq_unmask     = smp2p_unmask_irq,
 368         .irq_set_type   = smp2p_set_irq_type,
 369         .irq_print_chip = smp2p_irq_print_chip,
 370 };
 371
 372 static int smp2p_irq_map(struct irq_domain *d,
 373                          unsigned int irq,
 374                          irq_hw_number_t hw)
 375 {
 376         struct smp2p_entry *entry = d->host_data;
 377
 378         irq_set_chip_and_handler(irq, &smp2p_irq_chip, handle_level_irq);
 379         irq_set_chip_data(irq, entry);
 380         irq_set_nested_thread(irq, 1);
 381         irq_set_noprobe(irq);
 382
 383         return 0;
 384 }
 385
 386 static const struct irq_domain_ops smp2p_irq_ops = {
 387         .map = smp2p_irq_map,
 388         .xlate = irq_domain_xlate_twocell,
 389 };
 390
 391 static int qcom_smp2p_inbound_entry(struct qcom_smp2p *smp2p,
 392                                     struct smp2p_entry *entry,
 393                                     struct device_node *node)
 394 {
 395         entry->domain = irq_domain_add_linear(node, 32, &smp2p_irq_ops, entry);
 396         if (!entry->domain) {
 397                 dev_err(smp2p->dev, "failed to add irq_domain\n");
 398                 return -ENOMEM;
 399         }
 400
 401         return 0;
 402 }
 403
 404 static int smp2p_update_bits(void *data, u32 mask, u32 value)
 405 {
 406         struct smp2p_entry *entry = data;
 407         unsigned long flags;
 408         u32 orig;
 409         u32 val;
 410
 411         spin_lock_irqsave(&entry->lock, flags);
 412         val = orig = readl(entry->value);
 413         val &= ~mask;
 414         val |= value;
 415         writel(val, entry->value);
 416         spin_unlock_irqrestore(&entry->lock, flags);
 417
 418         if (val != orig)
 419                 qcom_smp2p_kick(entry->smp2p);
 420
 421         return 0;
 422 }
 423
 424 static const struct qcom_smem_state_ops smp2p_state_ops = {
 425         .update_bits = smp2p_update_bits,
 426 };
 427
 428 static int qcom_smp2p_outbound_entry(struct qcom_smp2p *smp2p,
 429                                      struct smp2p_entry *entry,
 430                                      struct device_node *node)
 431 {
 432         struct smp2p_smem_item *out = smp2p->out;
 433         char buf[SMP2P_MAX_ENTRY_NAME] = {};
 434
 435         /* Allocate an entry from the smem item */
 436         strscpy(buf, entry->name, SMP2P_MAX_ENTRY_NAME);
 437         memcpy(out->entries[out->valid_entries].name, buf, SMP2P_MAX_ENTRY_NAME);
 438
 439         /* Make the logical entry reference the physical value */
 440         entry->value = &out->entries[out->valid_entries].value;
 441
 442         out->valid_entries++;
 443
 444         entry->state = qcom_smem_state_register(node, &smp2p_state_ops, entry);
 445         if (IS_ERR(entry->state)) {
 446                 dev_err(smp2p->dev, "failed to register qcom_smem_state\n");
 447                 return PTR_ERR(entry->state);
 448         }
 449
 450         return 0;
 451 }
 452
 453 static int qcom_smp2p_alloc_outbound_item(struct qcom_smp2p *smp2p)
 454 {
 455         struct smp2p_smem_item *out;
 456         unsigned smem_id = smp2p->smem_items[SMP2P_OUTBOUND];
 457         unsigned pid = smp2p->remote_pid;
 458         int ret;
 459
 460         ret = qcom_smem_alloc(pid, smem_id, sizeof(*out));
 461         if (ret < 0 && ret != -EEXIST) {
 462                 if (ret != -EPROBE_DEFER)
 463                         dev_err(smp2p->dev,
 464                                 "unable to allocate local smp2p item\n");
 465                 return ret;
 466         }
 467
 468         out = qcom_smem_get(pid, smem_id, NULL);
 469         if (IS_ERR(out)) {
 470                 dev_err(smp2p->dev, "Unable to acquire local smp2p item\n");
 471                 return PTR_ERR(out);
 472         }
 473
 474         memset(out, 0, sizeof(*out));
 475         out->magic = SMP2P_MAGIC;
 476         out->local_pid = smp2p->local_pid;
 477         out->remote_pid = smp2p->remote_pid;
 478         out->total_entries = SMP2P_MAX_ENTRY;
 479         out->valid_entries = 0;
 480         out->features = SMP2P_ALL_FEATURES;
 481
 482         /*
 483          * Make sure the rest of the header is written before we validate the
 484          * item by writing a valid version number.
 485          */
 486         wmb();
 487         out->version = 1;
 488
 489         qcom_smp2p_kick(smp2p);
 490
 491         smp2p->out = out;
 492
 493         return 0;
 494 }
 495
 496 static int smp2p_parse_ipc(struct qcom_smp2p *smp2p)
 497 {
 498         struct device_node *syscon;
 499         struct device *dev = smp2p->dev;
 500         const char *key;
 501         int ret;
 502
 503         syscon = of_parse_phandle(dev->of_node, "qcom,ipc", 0);
 504         if (!syscon) {
 505                 dev_err(dev, "no qcom,ipc node\n");
 506                 return -ENODEV;
 507         }
 508
 509         smp2p->ipc_regmap = syscon_node_to_regmap(syscon);
 510         of_node_put(syscon);
 511         if (IS_ERR(smp2p->ipc_regmap))
 512                 return PTR_ERR(smp2p->ipc_regmap);
 513
 514         key = "qcom,ipc";
 515         ret = of_property_read_u32_index(dev->of_node, key, 1, &smp2p->ipc_offset);
 516         if (ret < 0) {
 517                 dev_err(dev, "no offset in %s\n", key);
 518                 return -EINVAL;
 519         }
 520
 521         ret = of_property_read_u32_index(dev->of_node, key, 2, &smp2p->ipc_bit);
 522         if (ret < 0) {
 523                 dev_err(dev, "no bit in %s\n", key);
 524                 return -EINVAL;
 525         }
 526
 527         return 0;
 528 }
 529
 530 static int qcom_smp2p_probe(struct platform_device *pdev)
 531 {
 532         struct smp2p_entry *entry;
 533         struct device_node *node;
 534         struct qcom_smp2p *smp2p;
 535         const char *key;
 536         int irq;
 537         int ret;
 538
 539         smp2p = devm_kzalloc(&pdev->dev, sizeof(*smp2p), GFP_KERNEL);
 540         if (!smp2p)
 541                 return -ENOMEM;
 542
 543         smp2p->dev = &pdev->dev;
 544         INIT_LIST_HEAD(&smp2p->inbound);
 545         INIT_LIST_HEAD(&smp2p->outbound);
 546
 547         platform_set_drvdata(pdev, smp2p);
 548
 549         key = "qcom,smem";
 550         ret = of_property_read_u32_array(pdev->dev.of_node, key,
 551                                          smp2p->smem_items, 2);
 552         if (ret)
 553                 return ret;
 554
 555         key = "qcom,local-pid";
 556         ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->local_pid);
 557         if (ret)
 558                 goto report_read_failure;
 559
 560         key = "qcom,remote-pid";
 561         ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->remote_pid);
 562         if (ret)
 563                 goto report_read_failure;
 564
 565         irq = platform_get_irq(pdev, 0);
 566         if (irq < 0)
 567                 return irq;
 568
 569         smp2p->mbox_client.dev = &pdev->dev;
 570         smp2p->mbox_client.knows_txdone = true;
 571         smp2p->mbox_chan = mbox_request_channel(&smp2p->mbox_client, 0);
 572         if (IS_ERR(smp2p->mbox_chan)) {
 573                 if (PTR_ERR(smp2p->mbox_chan) != -ENODEV)
 574                         return PTR_ERR(smp2p->mbox_chan);
 575
 576                 smp2p->mbox_chan = NULL;
 577
 578                 ret = smp2p_parse_ipc(smp2p);
 579                 if (ret)
 580                         return ret;
 581         }
 582
 583         ret = qcom_smp2p_alloc_outbound_item(smp2p);
 584         if (ret < 0)
 585                 goto release_mbox;
 586
 587         for_each_available_child_of_node(pdev->dev.of_node, node) {
 588                 entry = devm_kzalloc(&pdev->dev, sizeof(*entry), GFP_KERNEL);
 589                 if (!entry) {
 590                         ret = -ENOMEM;
 591                         of_node_put(node);
 592                         goto unwind_interfaces;
 593                 }
 594
 595                 entry->smp2p = smp2p;
 596                 spin_lock_init(&entry->lock);
 597
 598                 ret = of_property_read_string(node, "qcom,entry-name", &entry->name);
 599                 if (ret < 0) {
 600                         of_node_put(node);
 601                         goto unwind_interfaces;
 602                 }
 603
 604                 if (of_property_read_bool(node, "interrupt-controller")) {
 605                         ret = qcom_smp2p_inbound_entry(smp2p, entry, node);
 606                         if (ret < 0) {
 607                                 of_node_put(node);
 608                                 goto unwind_interfaces;
 609                         }
 610
 611                         list_add(&entry->node, &smp2p->inbound);
 612                 } else  {
 613                         ret = qcom_smp2p_outbound_entry(smp2p, entry, node);
 614                         if (ret < 0) {
 615                                 of_node_put(node);
 616                                 goto unwind_interfaces;
 617                         }
 618
 619                         list_add(&entry->node, &smp2p->outbound);
 620                 }
 621         }
 622
 623         /* Kick the outgoing edge after allocating entries */
 624         qcom_smp2p_kick(smp2p);
 625
 626         ret = devm_request_threaded_irq(&pdev->dev, irq,
 627                                         NULL, qcom_smp2p_intr,
 628                                         IRQF_ONESHOT,
 629                                         NULL, (void *)smp2p);
 630         if (ret) {
 631                 dev_err(&pdev->dev, "failed to request interrupt\n");
 632                 goto unwind_interfaces;
 633         }
 634
 635         /*
 636          * Treat smp2p interrupt as wakeup source, but keep it disabled
 637          * by default. User space can decide enabling it depending on its
 638          * use cases. For example if remoteproc crashes and device wants
 639          * to handle it immediatedly (e.g. to not miss phone calls) it can
 640          * enable wakeup source from user space, while other devices which
 641          * do not have proper autosleep feature may want to handle it with
 642          * other wakeup events (e.g. Power button) instead waking up immediately.
 643          */
 644         device_set_wakeup_capable(&pdev->dev, true);
 645
 646         ret = dev_pm_set_wake_irq(&pdev->dev, irq);
 647         if (ret)
 648                 goto set_wake_irq_fail;
 649
 650         return 0;
 651
 652 set_wake_irq_fail:
 653         dev_pm_clear_wake_irq(&pdev->dev);
 654
 655 unwind_interfaces:
 656         list_for_each_entry(entry, &smp2p->inbound, node)
 657                 irq_domain_remove(entry->domain);
 658
 659         list_for_each_entry(entry, &smp2p->outbound, node)
 660                 qcom_smem_state_unregister(entry->state);
 661
 662         smp2p->out->valid_entries = 0;
 663
 664 release_mbox:
 665         mbox_free_channel(smp2p->mbox_chan);
 666
 667         return ret;
 668
 669 report_read_failure:
 670         dev_err(&pdev->dev, "failed to read %s\n", key);
 671         return -EINVAL;
 672 }
 673
 674 static void qcom_smp2p_remove(struct platform_device *pdev)
 675 {
 676         struct qcom_smp2p *smp2p = platform_get_drvdata(pdev);
 677         struct smp2p_entry *entry;
 678
 679         dev_pm_clear_wake_irq(&pdev->dev);
 680
 681         list_for_each_entry(entry, &smp2p->inbound, node)
 682                 irq_domain_remove(entry->domain);
 683
 684         list_for_each_entry(entry, &smp2p->outbound, node)
 685                 qcom_smem_state_unregister(entry->state);
 686
 687         mbox_free_channel(smp2p->mbox_chan);
 688
 689         smp2p->out->valid_entries = 0;
 690 }
 691
 692 static const struct of_device_id qcom_smp2p_of_match[] = {
 693         { .compatible = "qcom,smp2p" },
 694         {}
 695 };
 696 MODULE_DEVICE_TABLE(of, qcom_smp2p_of_match);
 697
 698 static struct platform_driver qcom_smp2p_driver = {
 699         .probe = qcom_smp2p_probe,
 700         .remove_new = qcom_smp2p_remove,
 701         .driver  = {
 702                 .name  = "qcom_smp2p",
 703                 .of_match_table = qcom_smp2p_of_match,
 704         },
 705 };
 706 module_platform_driver(qcom_smp2p_driver);
 707
 708 MODULE_DESCRIPTION("Qualcomm Shared Memory Point to Point driver");
 709 MODULE_LICENSE("GPL v2");