drivers/vfio/platform/vfio_platform_common.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2013 - Virtual Open Systems
   4  * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
   5  */
   6
   7 #define dev_fmt(fmt)    "VFIO: " fmt
   8
   9 #include <linux/device.h>
  10 #include <linux/acpi.h>
  11 #include <linux/iommu.h>
  12 #include <linux/module.h>
  13 #include <linux/mutex.h>
  14 #include <linux/pm_runtime.h>
  15 #include <linux/slab.h>
  16 #include <linux/types.h>
  17 #include <linux/uaccess.h>
  18 #include <linux/vfio.h>
  19
  20 #include "vfio_platform_private.h"
  21
  22 #define DRIVER_VERSION  "0.10"
  23 #define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
  24 #define DRIVER_DESC     "VFIO platform base module"
  25
  26 #define VFIO_PLATFORM_IS_ACPI(vdev) ((vdev)->acpihid != NULL)
  27
  28 static LIST_HEAD(reset_list);
  29 static DEFINE_MUTEX(driver_lock);
  30
  31 static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
  32                                         struct module **module)
  33 {
  34         struct vfio_platform_reset_node *iter;
  35         vfio_platform_reset_fn_t reset_fn = NULL;
  36
  37         mutex_lock(&driver_lock);
  38         list_for_each_entry(iter, &reset_list, link) {
  39                 if (!strcmp(iter->compat, compat) &&
  40                         try_module_get(iter->owner)) {
  41                         *module = iter->owner;
  42                         reset_fn = iter->of_reset;
  43                         break;
  44                 }
  45         }
  46         mutex_unlock(&driver_lock);
  47         return reset_fn;
  48 }
  49
  50 static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
  51                                     struct device *dev)
  52 {
  53         struct acpi_device *adev;
  54
  55         if (acpi_disabled)
  56                 return -ENOENT;
  57
  58         adev = ACPI_COMPANION(dev);
  59         if (!adev) {
  60                 dev_err(dev, "ACPI companion device not found for %s\n",
  61                         vdev->name);
  62                 return -ENODEV;
  63         }
  64
  65 #ifdef CONFIG_ACPI
  66         vdev->acpihid = acpi_device_hid(adev);
  67 #endif
  68         return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
  69 }
  70
  71 static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
  72                                   const char **extra_dbg)
  73 {
  74 #ifdef CONFIG_ACPI
  75         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  76         struct device *dev = vdev->device;
  77         acpi_handle handle = ACPI_HANDLE(dev);
  78         acpi_status acpi_ret;
  79
  80         acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, &buffer);
  81         if (ACPI_FAILURE(acpi_ret)) {
  82                 if (extra_dbg)
  83                         *extra_dbg = acpi_format_exception(acpi_ret);
  84                 return -EINVAL;
  85         }
  86
  87         return 0;
  88 #else
  89         return -ENOENT;
  90 #endif
  91 }
  92
  93 static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
  94 {
  95 #ifdef CONFIG_ACPI
  96         struct device *dev = vdev->device;
  97         acpi_handle handle = ACPI_HANDLE(dev);
  98
  99         return acpi_has_method(handle, "_RST");
 100 #else
 101         return false;
 102 #endif
 103 }
 104
 105 static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
 106 {
 107         if (VFIO_PLATFORM_IS_ACPI(vdev))
 108                 return vfio_platform_acpi_has_reset(vdev);
 109
 110         return vdev->of_reset ? true : false;
 111 }
 112
 113 static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
 114 {
 115         if (VFIO_PLATFORM_IS_ACPI(vdev))
 116                 return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
 117
 118         vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
 119                                                     &vdev->reset_module);
 120         if (!vdev->of_reset) {
 121                 request_module("vfio-reset:%s", vdev->compat);
 122                 vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
 123                                                         &vdev->reset_module);
 124         }
 125
 126         return vdev->of_reset ? 0 : -ENOENT;
 127 }
 128
 129 static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
 130 {
 131         if (VFIO_PLATFORM_IS_ACPI(vdev))
 132                 return;
 133
 134         if (vdev->of_reset)
 135                 module_put(vdev->reset_module);
 136 }
 137
 138 static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
 139 {
 140         int cnt = 0, i;
 141
 142         while (vdev->get_resource(vdev, cnt))
 143                 cnt++;
 144
 145         vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
 146                                 GFP_KERNEL);
 147         if (!vdev->regions)
 148                 return -ENOMEM;
 149
 150         for (i = 0; i < cnt;  i++) {
 151                 struct resource *res =
 152                         vdev->get_resource(vdev, i);
 153
 154                 if (!res)
 155                         goto err;
 156
 157                 vdev->regions[i].addr = res->start;
 158                 vdev->regions[i].size = resource_size(res);
 159                 vdev->regions[i].flags = 0;
 160
 161                 switch (resource_type(res)) {
 162                 case IORESOURCE_MEM:
 163                         vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
 164                         vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
 165                         if (!(res->flags & IORESOURCE_READONLY))
 166                                 vdev->regions[i].flags |=
 167                                         VFIO_REGION_INFO_FLAG_WRITE;
 168
 169                         /*
 170                          * Only regions addressed with PAGE granularity may be
 171                          * MMAPed securely.
 172                          */
 173                         if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
 174                                         !(vdev->regions[i].size & ~PAGE_MASK))
 175                                 vdev->regions[i].flags |=
 176                                         VFIO_REGION_INFO_FLAG_MMAP;
 177
 178                         break;
 179                 case IORESOURCE_IO:
 180                         vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
 181                         break;
 182                 default:
 183                         goto err;
 184                 }
 185         }
 186
 187         vdev->num_regions = cnt;
 188
 189         return 0;
 190 err:
 191         kfree(vdev->regions);
 192         return -EINVAL;
 193 }
 194
 195 static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
 196 {
 197         int i;
 198
 199         for (i = 0; i < vdev->num_regions; i++)
 200                 iounmap(vdev->regions[i].ioaddr);
 201
 202         vdev->num_regions = 0;
 203         kfree(vdev->regions);
 204 }
 205
 206 static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
 207                                     const char **extra_dbg)
 208 {
 209         if (VFIO_PLATFORM_IS_ACPI(vdev)) {
 210                 dev_info(vdev->device, "reset\n");
 211                 return vfio_platform_acpi_call_reset(vdev, extra_dbg);
 212         } else if (vdev->of_reset) {
 213                 dev_info(vdev->device, "reset\n");
 214                 return vdev->of_reset(vdev);
 215         }
 216
 217         dev_warn(vdev->device, "no reset function found!\n");
 218         return -EINVAL;
 219 }
 220
 221 static void vfio_platform_release(struct vfio_device *core_vdev)
 222 {
 223         struct vfio_platform_device *vdev =
 224                 container_of(core_vdev, struct vfio_platform_device, vdev);
 225
 226         mutex_lock(&driver_lock);
 227
 228         if (!(--vdev->refcnt)) {
 229                 const char *extra_dbg = NULL;
 230                 int ret;
 231
 232                 ret = vfio_platform_call_reset(vdev, &extra_dbg);
 233                 if (ret && vdev->reset_required) {
 234                         dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
 235                                  ret, extra_dbg ? extra_dbg : "");
 236                         WARN_ON(1);
 237                 }
 238                 pm_runtime_put(vdev->device);
 239                 vfio_platform_regions_cleanup(vdev);
 240                 vfio_platform_irq_cleanup(vdev);
 241         }
 242
 243         mutex_unlock(&driver_lock);
 244
 245         module_put(vdev->parent_module);
 246 }
 247
 248 static int vfio_platform_open(struct vfio_device *core_vdev)
 249 {
 250         struct vfio_platform_device *vdev =
 251                 container_of(core_vdev, struct vfio_platform_device, vdev);
 252         int ret;
 253
 254         if (!try_module_get(vdev->parent_module))
 255                 return -ENODEV;
 256
 257         mutex_lock(&driver_lock);
 258
 259         if (!vdev->refcnt) {
 260                 const char *extra_dbg = NULL;
 261
 262                 ret = vfio_platform_regions_init(vdev);
 263                 if (ret)
 264                         goto err_reg;
 265
 266                 ret = vfio_platform_irq_init(vdev);
 267                 if (ret)
 268                         goto err_irq;
 269
 270                 ret = pm_runtime_get_sync(vdev->device);
 271                 if (ret < 0)
 272                         goto err_rst;
 273
 274                 ret = vfio_platform_call_reset(vdev, &extra_dbg);
 275                 if (ret && vdev->reset_required) {
 276                         dev_warn(vdev->device, "reset driver is required and reset call failed in open (%d) %s\n",
 277                                  ret, extra_dbg ? extra_dbg : "");
 278                         goto err_rst;
 279                 }
 280         }
 281
 282         vdev->refcnt++;
 283
 284         mutex_unlock(&driver_lock);
 285         return 0;
 286
 287 err_rst:
 288         pm_runtime_put(vdev->device);
 289         vfio_platform_irq_cleanup(vdev);
 290 err_irq:
 291         vfio_platform_regions_cleanup(vdev);
 292 err_reg:
 293         mutex_unlock(&driver_lock);
 294         module_put(vdev->parent_module);
 295         return ret;
 296 }
 297
 298 static long vfio_platform_ioctl(struct vfio_device *core_vdev,
 299                                 unsigned int cmd, unsigned long arg)
 300 {
 301         struct vfio_platform_device *vdev =
 302                 container_of(core_vdev, struct vfio_platform_device, vdev);
 303
 304         unsigned long minsz;
 305
 306         if (cmd == VFIO_DEVICE_GET_INFO) {
 307                 struct vfio_device_info info;
 308
 309                 minsz = offsetofend(struct vfio_device_info, num_irqs);
 310
 311                 if (copy_from_user(&info, (void __user *)arg, minsz))
 312                         return -EFAULT;
 313
 314                 if (info.argsz < minsz)
 315                         return -EINVAL;
 316
 317                 if (vfio_platform_has_reset(vdev))
 318                         vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
 319                 info.flags = vdev->flags;
 320                 info.num_regions = vdev->num_regions;
 321                 info.num_irqs = vdev->num_irqs;
 322
 323                 return copy_to_user((void __user *)arg, &info, minsz) ?
 324                         -EFAULT : 0;
 325
 326         } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
 327                 struct vfio_region_info info;
 328
 329                 minsz = offsetofend(struct vfio_region_info, offset);
 330
 331                 if (copy_from_user(&info, (void __user *)arg, minsz))
 332                         return -EFAULT;
 333
 334                 if (info.argsz < minsz)
 335                         return -EINVAL;
 336
 337                 if (info.index >= vdev->num_regions)
 338                         return -EINVAL;
 339
 340                 /* map offset to the physical address  */
 341                 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
 342                 info.size = vdev->regions[info.index].size;
 343                 info.flags = vdev->regions[info.index].flags;
 344
 345                 return copy_to_user((void __user *)arg, &info, minsz) ?
 346                         -EFAULT : 0;
 347
 348         } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
 349                 struct vfio_irq_info info;
 350
 351                 minsz = offsetofend(struct vfio_irq_info, count);
 352
 353                 if (copy_from_user(&info, (void __user *)arg, minsz))
 354                         return -EFAULT;
 355
 356                 if (info.argsz < minsz)
 357                         return -EINVAL;
 358
 359                 if (info.index >= vdev->num_irqs)
 360                         return -EINVAL;
 361
 362                 info.flags = vdev->irqs[info.index].flags;
 363                 info.count = vdev->irqs[info.index].count;
 364
 365                 return copy_to_user((void __user *)arg, &info, minsz) ?
 366                         -EFAULT : 0;
 367
 368         } else if (cmd == VFIO_DEVICE_SET_IRQS) {
 369                 struct vfio_irq_set hdr;
 370                 u8 *data = NULL;
 371                 int ret = 0;
 372                 size_t data_size = 0;
 373
 374                 minsz = offsetofend(struct vfio_irq_set, count);
 375
 376                 if (copy_from_user(&hdr, (void __user *)arg, minsz))
 377                         return -EFAULT;
 378
 379                 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
 380                                                  vdev->num_irqs, &data_size);
 381                 if (ret)
 382                         return ret;
 383
 384                 if (data_size) {
 385                         data = memdup_user((void __user *)(arg + minsz),
 386                                             data_size);
 387                         if (IS_ERR(data))
 388                                 return PTR_ERR(data);
 389                 }
 390
 391                 mutex_lock(&vdev->igate);
 392
 393                 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
 394                                                    hdr.start, hdr.count, data);
 395                 mutex_unlock(&vdev->igate);
 396                 kfree(data);
 397
 398                 return ret;
 399
 400         } else if (cmd == VFIO_DEVICE_RESET) {
 401                 return vfio_platform_call_reset(vdev, NULL);
 402         }
 403
 404         return -ENOTTY;
 405 }
 406
 407 static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
 408                                        char __user *buf, size_t count,
 409                                        loff_t off)
 410 {
 411         unsigned int done = 0;
 412
 413         if (!reg->ioaddr) {
 414                 reg->ioaddr =
 415                         ioremap(reg->addr, reg->size);
 416
 417                 if (!reg->ioaddr)
 418                         return -ENOMEM;
 419         }
 420
 421         while (count) {
 422                 size_t filled;
 423
 424                 if (count >= 4 && !(off % 4)) {
 425                         u32 val;
 426
 427                         val = ioread32(reg->ioaddr + off);
 428                         if (copy_to_user(buf, &val, 4))
 429                                 goto err;
 430
 431                         filled = 4;
 432                 } else if (count >= 2 && !(off % 2)) {
 433                         u16 val;
 434
 435                         val = ioread16(reg->ioaddr + off);
 436                         if (copy_to_user(buf, &val, 2))
 437                                 goto err;
 438
 439                         filled = 2;
 440                 } else {
 441                         u8 val;
 442
 443                         val = ioread8(reg->ioaddr + off);
 444                         if (copy_to_user(buf, &val, 1))
 445                                 goto err;
 446
 447                         filled = 1;
 448                 }
 449
 450
 451                 count -= filled;
 452                 done += filled;
 453                 off += filled;
 454                 buf += filled;
 455         }
 456
 457         return done;
 458 err:
 459         return -EFAULT;
 460 }
 461
 462 static ssize_t vfio_platform_read(struct vfio_device *core_vdev,
 463                                   char __user *buf, size_t count, loff_t *ppos)
 464 {
 465         struct vfio_platform_device *vdev =
 466                 container_of(core_vdev, struct vfio_platform_device, vdev);
 467         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 468         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 469
 470         if (index >= vdev->num_regions)
 471                 return -EINVAL;
 472
 473         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
 474                 return -EINVAL;
 475
 476         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 477                 return vfio_platform_read_mmio(&vdev->regions[index],
 478                                                         buf, count, off);
 479         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 480                 return -EINVAL; /* not implemented */
 481
 482         return -EINVAL;
 483 }
 484
 485 static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
 486                                         const char __user *buf, size_t count,
 487                                         loff_t off)
 488 {
 489         unsigned int done = 0;
 490
 491         if (!reg->ioaddr) {
 492                 reg->ioaddr =
 493                         ioremap(reg->addr, reg->size);
 494
 495                 if (!reg->ioaddr)
 496                         return -ENOMEM;
 497         }
 498
 499         while (count) {
 500                 size_t filled;
 501
 502                 if (count >= 4 && !(off % 4)) {
 503                         u32 val;
 504
 505                         if (copy_from_user(&val, buf, 4))
 506                                 goto err;
 507                         iowrite32(val, reg->ioaddr + off);
 508
 509                         filled = 4;
 510                 } else if (count >= 2 && !(off % 2)) {
 511                         u16 val;
 512
 513                         if (copy_from_user(&val, buf, 2))
 514                                 goto err;
 515                         iowrite16(val, reg->ioaddr + off);
 516
 517                         filled = 2;
 518                 } else {
 519                         u8 val;
 520
 521                         if (copy_from_user(&val, buf, 1))
 522                                 goto err;
 523                         iowrite8(val, reg->ioaddr + off);
 524
 525                         filled = 1;
 526                 }
 527
 528                 count -= filled;
 529                 done += filled;
 530                 off += filled;
 531                 buf += filled;
 532         }
 533
 534         return done;
 535 err:
 536         return -EFAULT;
 537 }
 538
 539 static ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
 540                                    size_t count, loff_t *ppos)
 541 {
 542         struct vfio_platform_device *vdev =
 543                 container_of(core_vdev, struct vfio_platform_device, vdev);
 544         unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 545         loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 546
 547         if (index >= vdev->num_regions)
 548                 return -EINVAL;
 549
 550         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
 551                 return -EINVAL;
 552
 553         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 554                 return vfio_platform_write_mmio(&vdev->regions[index],
 555                                                         buf, count, off);
 556         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 557                 return -EINVAL; /* not implemented */
 558
 559         return -EINVAL;
 560 }
 561
 562 static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
 563                                    struct vm_area_struct *vma)
 564 {
 565         u64 req_len, pgoff, req_start;
 566
 567         req_len = vma->vm_end - vma->vm_start;
 568         pgoff = vma->vm_pgoff &
 569                 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
 570         req_start = pgoff << PAGE_SHIFT;
 571
 572         if (region.size < PAGE_SIZE || req_start + req_len > region.size)
 573                 return -EINVAL;
 574
 575         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 576         vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
 577
 578         return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 579                                req_len, vma->vm_page_prot);
 580 }
 581
 582 static int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
 583 {
 584         struct vfio_platform_device *vdev =
 585                 container_of(core_vdev, struct vfio_platform_device, vdev);
 586         unsigned int index;
 587
 588         index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
 589
 590         if (vma->vm_end < vma->vm_start)
 591                 return -EINVAL;
 592         if (!(vma->vm_flags & VM_SHARED))
 593                 return -EINVAL;
 594         if (index >= vdev->num_regions)
 595                 return -EINVAL;
 596         if (vma->vm_start & ~PAGE_MASK)
 597                 return -EINVAL;
 598         if (vma->vm_end & ~PAGE_MASK)
 599                 return -EINVAL;
 600
 601         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
 602                 return -EINVAL;
 603
 604         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
 605                         && (vma->vm_flags & VM_READ))
 606                 return -EINVAL;
 607
 608         if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
 609                         && (vma->vm_flags & VM_WRITE))
 610                 return -EINVAL;
 611
 612         vma->vm_private_data = vdev;
 613
 614         if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
 615                 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
 616
 617         else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
 618                 return -EINVAL; /* not implemented */
 619
 620         return -EINVAL;
 621 }
 622
 623 static const struct vfio_device_ops vfio_platform_ops = {
 624         .name           = "vfio-platform",
 625         .open           = vfio_platform_open,
 626         .release        = vfio_platform_release,
 627         .ioctl          = vfio_platform_ioctl,
 628         .read           = vfio_platform_read,
 629         .write          = vfio_platform_write,
 630         .mmap           = vfio_platform_mmap,
 631 };
 632
 633 static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
 634                            struct device *dev)
 635 {
 636         int ret;
 637
 638         ret = device_property_read_string(dev, "compatible",
 639                                           &vdev->compat);
 640         if (ret)
 641                 dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
 642
 643         return ret;
 644 }
 645
 646 /*
 647  * There can be two kernel build combinations. One build where
 648  * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
 649  *
 650  * In the first case, vfio_platform_acpi_probe will return since
 651  * acpi_disabled is 1. DT user will not see any kind of messages from
 652  * ACPI.
 653  *
 654  * In the second case, both DT and ACPI is compiled in but the system is
 655  * booting with any of these combinations.
 656  *
 657  * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
 658  * terminates immediately without any messages.
 659  *
 660  * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
 661  * valid checks. We cannot claim that this system is DT.
 662  */
 663 int vfio_platform_probe_common(struct vfio_platform_device *vdev,
 664                                struct device *dev)
 665 {
 666         struct iommu_group *group;
 667         int ret;
 668
 669         vfio_init_group_dev(&vdev->vdev, dev, &vfio_platform_ops);
 670
 671         ret = vfio_platform_acpi_probe(vdev, dev);
 672         if (ret)
 673                 ret = vfio_platform_of_probe(vdev, dev);
 674
 675         if (ret)
 676                 return ret;
 677
 678         vdev->device = dev;
 679
 680         ret = vfio_platform_get_reset(vdev);
 681         if (ret && vdev->reset_required) {
 682                 dev_err(dev, "No reset function found for device %s\n",
 683                         vdev->name);
 684                 return ret;
 685         }
 686
 687         group = vfio_iommu_group_get(dev);
 688         if (!group) {
 689                 dev_err(dev, "No IOMMU group for device %s\n", vdev->name);
 690                 ret = -EINVAL;
 691                 goto put_reset;
 692         }
 693
 694         ret = vfio_register_group_dev(&vdev->vdev);
 695         if (ret)
 696                 goto put_iommu;
 697
 698         mutex_init(&vdev->igate);
 699
 700         pm_runtime_enable(dev);
 701         return 0;
 702
 703 put_iommu:
 704         vfio_iommu_group_put(group, dev);
 705 put_reset:
 706         vfio_platform_put_reset(vdev);
 707         return ret;
 708 }
 709 EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
 710
 711 void vfio_platform_remove_common(struct vfio_platform_device *vdev)
 712 {
 713         vfio_unregister_group_dev(&vdev->vdev);
 714
 715         pm_runtime_disable(vdev->device);
 716         vfio_platform_put_reset(vdev);
 717         vfio_iommu_group_put(vdev->vdev.dev->iommu_group, vdev->vdev.dev);
 718 }
 719 EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
 720
 721 void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
 722 {
 723         mutex_lock(&driver_lock);
 724         list_add(&node->link, &reset_list);
 725         mutex_unlock(&driver_lock);
 726 }
 727 EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
 728
 729 void vfio_platform_unregister_reset(const char *compat,
 730                                     vfio_platform_reset_fn_t fn)
 731 {
 732         struct vfio_platform_reset_node *iter, *temp;
 733
 734         mutex_lock(&driver_lock);
 735         list_for_each_entry_safe(iter, temp, &reset_list, link) {
 736                 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
 737                         list_del(&iter->link);
 738                         break;
 739                 }
 740         }
 741
 742         mutex_unlock(&driver_lock);
 743
 744 }
 745 EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
 746
 747 MODULE_VERSION(DRIVER_VERSION);
 748 MODULE_LICENSE("GPL v2");
 749 MODULE_AUTHOR(DRIVER_AUTHOR);
 750 MODULE_DESCRIPTION(DRIVER_DESC);