1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Mediated virtual PCI display host device driver 4 * 5 * See mdpy-defs.h for device specs 6 * 7 * (c) Gerd Hoffmann <kraxel@redhat.com> 8 * 9 * based on mtty driver which is: 10 * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. 11 * Author: Neo Jia <cjia@nvidia.com> 12 * Kirti Wankhede <kwankhede@nvidia.com> 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License version 2 as 16 * published by the Free Software Foundation. 17 */ 18 #include <linux/init.h> 19 #include <linux/module.h> 20 #include <linux/kernel.h> 21 #include <linux/slab.h> 22 #include <linux/vmalloc.h> 23 #include <linux/cdev.h> 24 #include <linux/vfio.h> 25 #include <linux/iommu.h> 26 #include <linux/sysfs.h> 27 #include <linux/mdev.h> 28 #include <linux/pci.h> 29 #include <drm/drm_fourcc.h> 30 #include "mdpy-defs.h" 31 32 #define MDPY_NAME "mdpy" 33 #define MDPY_CLASS_NAME "mdpy" 34 35 #define MDPY_CONFIG_SPACE_SIZE 0xff 36 #define MDPY_MEMORY_BAR_OFFSET PAGE_SIZE 37 #define MDPY_DISPLAY_REGION 16 38 39 #define STORE_LE16(addr, val) (*(u16 *)addr = val) 40 #define STORE_LE32(addr, val) (*(u32 *)addr = val) 41 42 43 MODULE_DESCRIPTION("Mediated virtual PCI display host device driver"); 44 MODULE_LICENSE("GPL v2"); 45 46 #define MDPY_TYPE_1 "vga" 47 #define MDPY_TYPE_2 "xga" 48 #define MDPY_TYPE_3 "hd" 49 50 static struct mdpy_type { 51 struct mdev_type type; 52 u32 format; 53 u32 bytepp; 54 u32 width; 55 u32 height; 56 } mdpy_types[] = { 57 { 58 .type.sysfs_name = MDPY_TYPE_1, 59 .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_1, 60 .format = DRM_FORMAT_XRGB8888, 61 .bytepp = 4, 62 .width = 640, 63 .height = 480, 64 }, { 65 .type.sysfs_name = MDPY_TYPE_2, 66 .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_2, 67 .format = DRM_FORMAT_XRGB8888, 68 .bytepp = 4, 69 .width = 1024, 70 .height = 768, 71 }, { 72 .type.sysfs_name = MDPY_TYPE_3, 73 .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_3, 74 .format = DRM_FORMAT_XRGB8888, 75 .bytepp = 4, 76 .width = 1920, 77 .height = 1080, 78 }, 79 }; 80 81 static struct mdev_type *mdpy_mdev_types[] = { 82 &mdpy_types[0].type, 83 &mdpy_types[1].type, 84 &mdpy_types[2].type, 85 }; 86 87 static dev_t mdpy_devt; 88 static const struct class mdpy_class = { 89 .name = MDPY_CLASS_NAME, 90 }; 91 static struct cdev mdpy_cdev; 92 static struct device mdpy_dev; 93 static struct mdev_parent mdpy_parent; 94 static const struct vfio_device_ops mdpy_dev_ops; 95 96 /* State of each mdev device */ 97 struct mdev_state { 98 struct vfio_device vdev; 99 u8 *vconfig; 100 u32 bar_mask; 101 struct mutex ops_lock; 102 struct mdev_device *mdev; 103 struct vfio_device_info dev_info; 104 105 const struct mdpy_type *type; 106 u32 memsize; 107 void *memblk; 108 }; 109 110 static void mdpy_create_config_space(struct mdev_state *mdev_state) 111 { 112 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID], 113 MDPY_PCI_VENDOR_ID); 114 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID], 115 MDPY_PCI_DEVICE_ID); 116 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID], 117 MDPY_PCI_SUBVENDOR_ID); 118 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID], 119 MDPY_PCI_SUBDEVICE_ID); 120 121 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND], 122 PCI_COMMAND_IO | PCI_COMMAND_MEMORY); 123 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_STATUS], 124 PCI_STATUS_CAP_LIST); 125 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE], 126 PCI_CLASS_DISPLAY_OTHER); 127 mdev_state->vconfig[PCI_CLASS_REVISION] = 0x01; 128 129 STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0], 130 PCI_BASE_ADDRESS_SPACE_MEMORY | 131 PCI_BASE_ADDRESS_MEM_TYPE_32 | 132 PCI_BASE_ADDRESS_MEM_PREFETCH); 133 mdev_state->bar_mask = ~(mdev_state->memsize) + 1; 134 135 /* vendor specific capability for the config registers */ 136 mdev_state->vconfig[PCI_CAPABILITY_LIST] = MDPY_VENDORCAP_OFFSET; 137 mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 0] = 0x09; /* vendor cap */ 138 mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 1] = 0x00; /* next ptr */ 139 mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 2] = MDPY_VENDORCAP_SIZE; 140 STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_FORMAT_OFFSET], 141 mdev_state->type->format); 142 STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_WIDTH_OFFSET], 143 mdev_state->type->width); 144 STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_HEIGHT_OFFSET], 145 mdev_state->type->height); 146 } 147 148 static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset, 149 char *buf, u32 count) 150 { 151 struct device *dev = mdev_dev(mdev_state->mdev); 152 u32 cfg_addr; 153 154 switch (offset) { 155 case PCI_BASE_ADDRESS_0: 156 cfg_addr = *(u32 *)buf; 157 158 if (cfg_addr == 0xffffffff) { 159 cfg_addr = (cfg_addr & mdev_state->bar_mask); 160 } else { 161 cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK; 162 if (cfg_addr) 163 dev_info(dev, "BAR0 @ 0x%x\n", cfg_addr); 164 } 165 166 cfg_addr |= (mdev_state->vconfig[offset] & 167 ~PCI_BASE_ADDRESS_MEM_MASK); 168 STORE_LE32(&mdev_state->vconfig[offset], cfg_addr); 169 break; 170 } 171 } 172 173 static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf, 174 size_t count, loff_t pos, bool is_write) 175 { 176 int ret = 0; 177 178 mutex_lock(&mdev_state->ops_lock); 179 180 if (pos < MDPY_CONFIG_SPACE_SIZE) { 181 if (is_write) 182 handle_pci_cfg_write(mdev_state, pos, buf, count); 183 else 184 memcpy(buf, (mdev_state->vconfig + pos), count); 185 186 } else if ((pos >= MDPY_MEMORY_BAR_OFFSET) && 187 (pos + count <= 188 MDPY_MEMORY_BAR_OFFSET + mdev_state->memsize)) { 189 pos -= MDPY_MEMORY_BAR_OFFSET; 190 if (is_write) 191 memcpy(mdev_state->memblk, buf, count); 192 else 193 memcpy(buf, mdev_state->memblk, count); 194 195 } else { 196 dev_info(mdev_state->vdev.dev, 197 "%s: %s @0x%llx (unhandled)\n", __func__, 198 is_write ? "WR" : "RD", pos); 199 ret = -1; 200 goto accessfailed; 201 } 202 203 ret = count; 204 205 206 accessfailed: 207 mutex_unlock(&mdev_state->ops_lock); 208 209 return ret; 210 } 211 212 static int mdpy_reset(struct mdev_state *mdev_state) 213 { 214 u32 stride, i; 215 216 /* initialize with gray gradient */ 217 stride = mdev_state->type->width * mdev_state->type->bytepp; 218 for (i = 0; i < mdev_state->type->height; i++) 219 memset(mdev_state->memblk + i * stride, 220 i * 255 / mdev_state->type->height, 221 stride); 222 return 0; 223 } 224 225 static int mdpy_init_dev(struct vfio_device *vdev) 226 { 227 struct mdev_state *mdev_state = 228 container_of(vdev, struct mdev_state, vdev); 229 struct mdev_device *mdev = to_mdev_device(vdev->dev); 230 const struct mdpy_type *type = 231 container_of(mdev->type, struct mdpy_type, type); 232 u32 fbsize; 233 int ret = -ENOMEM; 234 235 mdev_state->vconfig = kzalloc(MDPY_CONFIG_SPACE_SIZE, GFP_KERNEL); 236 if (!mdev_state->vconfig) 237 return ret; 238 239 fbsize = roundup_pow_of_two(type->width * type->height * type->bytepp); 240 241 mdev_state->memblk = vmalloc_user(fbsize); 242 if (!mdev_state->memblk) 243 goto out_vconfig; 244 245 mutex_init(&mdev_state->ops_lock); 246 mdev_state->mdev = mdev; 247 mdev_state->type = type; 248 mdev_state->memsize = fbsize; 249 mdpy_create_config_space(mdev_state); 250 mdpy_reset(mdev_state); 251 252 dev_info(vdev->dev, "%s: %s (%dx%d)\n", __func__, type->type.pretty_name, 253 type->width, type->height); 254 return 0; 255 256 out_vconfig: 257 kfree(mdev_state->vconfig); 258 return ret; 259 } 260 261 static int mdpy_probe(struct mdev_device *mdev) 262 { 263 struct mdev_state *mdev_state; 264 int ret; 265 266 mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev, 267 &mdpy_dev_ops); 268 if (IS_ERR(mdev_state)) 269 return PTR_ERR(mdev_state); 270 271 ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev); 272 if (ret) 273 goto err_put_vdev; 274 dev_set_drvdata(&mdev->dev, mdev_state); 275 return 0; 276 277 err_put_vdev: 278 vfio_put_device(&mdev_state->vdev); 279 return ret; 280 } 281 282 static void mdpy_release_dev(struct vfio_device *vdev) 283 { 284 struct mdev_state *mdev_state = 285 container_of(vdev, struct mdev_state, vdev); 286 287 vfree(mdev_state->memblk); 288 kfree(mdev_state->vconfig); 289 } 290 291 static void mdpy_remove(struct mdev_device *mdev) 292 { 293 struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev); 294 295 dev_info(&mdev->dev, "%s\n", __func__); 296 297 vfio_unregister_group_dev(&mdev_state->vdev); 298 vfio_put_device(&mdev_state->vdev); 299 } 300 301 static ssize_t mdpy_read(struct vfio_device *vdev, char __user *buf, 302 size_t count, loff_t *ppos) 303 { 304 struct mdev_state *mdev_state = 305 container_of(vdev, struct mdev_state, vdev); 306 unsigned int done = 0; 307 int ret; 308 309 while (count) { 310 size_t filled; 311 312 if (count >= 4 && !(*ppos % 4)) { 313 u32 val; 314 315 ret = mdev_access(mdev_state, (char *)&val, sizeof(val), 316 *ppos, false); 317 if (ret <= 0) 318 goto read_err; 319 320 if (copy_to_user(buf, &val, sizeof(val))) 321 goto read_err; 322 323 filled = 4; 324 } else if (count >= 2 && !(*ppos % 2)) { 325 u16 val; 326 327 ret = mdev_access(mdev_state, (char *)&val, sizeof(val), 328 *ppos, false); 329 if (ret <= 0) 330 goto read_err; 331 332 if (copy_to_user(buf, &val, sizeof(val))) 333 goto read_err; 334 335 filled = 2; 336 } else { 337 u8 val; 338 339 ret = mdev_access(mdev_state, (char *)&val, sizeof(val), 340 *ppos, false); 341 if (ret <= 0) 342 goto read_err; 343 344 if (copy_to_user(buf, &val, sizeof(val))) 345 goto read_err; 346 347 filled = 1; 348 } 349 350 count -= filled; 351 done += filled; 352 *ppos += filled; 353 buf += filled; 354 } 355 356 return done; 357 358 read_err: 359 return -EFAULT; 360 } 361 362 static ssize_t mdpy_write(struct vfio_device *vdev, const char __user *buf, 363 size_t count, loff_t *ppos) 364 { 365 struct mdev_state *mdev_state = 366 container_of(vdev, struct mdev_state, vdev); 367 unsigned int done = 0; 368 int ret; 369 370 while (count) { 371 size_t filled; 372 373 if (count >= 4 && !(*ppos % 4)) { 374 u32 val; 375 376 if (copy_from_user(&val, buf, sizeof(val))) 377 goto write_err; 378 379 ret = mdev_access(mdev_state, (char *)&val, sizeof(val), 380 *ppos, true); 381 if (ret <= 0) 382 goto write_err; 383 384 filled = 4; 385 } else if (count >= 2 && !(*ppos % 2)) { 386 u16 val; 387 388 if (copy_from_user(&val, buf, sizeof(val))) 389 goto write_err; 390 391 ret = mdev_access(mdev_state, (char *)&val, sizeof(val), 392 *ppos, true); 393 if (ret <= 0) 394 goto write_err; 395 396 filled = 2; 397 } else { 398 u8 val; 399 400 if (copy_from_user(&val, buf, sizeof(val))) 401 goto write_err; 402 403 ret = mdev_access(mdev_state, (char *)&val, sizeof(val), 404 *ppos, true); 405 if (ret <= 0) 406 goto write_err; 407 408 filled = 1; 409 } 410 count -= filled; 411 done += filled; 412 *ppos += filled; 413 buf += filled; 414 } 415 416 return done; 417 write_err: 418 return -EFAULT; 419 } 420 421 static int mdpy_mmap(struct vfio_device *vdev, struct vm_area_struct *vma) 422 { 423 struct mdev_state *mdev_state = 424 container_of(vdev, struct mdev_state, vdev); 425 426 if (vma->vm_pgoff != MDPY_MEMORY_BAR_OFFSET >> PAGE_SHIFT) 427 return -EINVAL; 428 if (vma->vm_end < vma->vm_start) 429 return -EINVAL; 430 if (vma->vm_end - vma->vm_start > mdev_state->memsize) 431 return -EINVAL; 432 if ((vma->vm_flags & VM_SHARED) == 0) 433 return -EINVAL; 434 435 return remap_vmalloc_range(vma, mdev_state->memblk, 0); 436 } 437 438 static int mdpy_get_region_info(struct mdev_state *mdev_state, 439 struct vfio_region_info *region_info, 440 u16 *cap_type_id, void **cap_type) 441 { 442 if (region_info->index >= VFIO_PCI_NUM_REGIONS && 443 region_info->index != MDPY_DISPLAY_REGION) 444 return -EINVAL; 445 446 switch (region_info->index) { 447 case VFIO_PCI_CONFIG_REGION_INDEX: 448 region_info->offset = 0; 449 region_info->size = MDPY_CONFIG_SPACE_SIZE; 450 region_info->flags = (VFIO_REGION_INFO_FLAG_READ | 451 VFIO_REGION_INFO_FLAG_WRITE); 452 break; 453 case VFIO_PCI_BAR0_REGION_INDEX: 454 case MDPY_DISPLAY_REGION: 455 region_info->offset = MDPY_MEMORY_BAR_OFFSET; 456 region_info->size = mdev_state->memsize; 457 region_info->flags = (VFIO_REGION_INFO_FLAG_READ | 458 VFIO_REGION_INFO_FLAG_WRITE | 459 VFIO_REGION_INFO_FLAG_MMAP); 460 break; 461 default: 462 region_info->size = 0; 463 region_info->offset = 0; 464 region_info->flags = 0; 465 } 466 467 return 0; 468 } 469 470 static int mdpy_get_irq_info(struct vfio_irq_info *irq_info) 471 { 472 irq_info->count = 0; 473 return 0; 474 } 475 476 static int mdpy_get_device_info(struct vfio_device_info *dev_info) 477 { 478 dev_info->flags = VFIO_DEVICE_FLAGS_PCI; 479 dev_info->num_regions = VFIO_PCI_NUM_REGIONS; 480 dev_info->num_irqs = VFIO_PCI_NUM_IRQS; 481 return 0; 482 } 483 484 static int mdpy_query_gfx_plane(struct mdev_state *mdev_state, 485 struct vfio_device_gfx_plane_info *plane) 486 { 487 if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) { 488 if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE | 489 VFIO_GFX_PLANE_TYPE_REGION)) 490 return 0; 491 return -EINVAL; 492 } 493 494 if (plane->flags != VFIO_GFX_PLANE_TYPE_REGION) 495 return -EINVAL; 496 497 plane->drm_format = mdev_state->type->format; 498 plane->width = mdev_state->type->width; 499 plane->height = mdev_state->type->height; 500 plane->stride = (mdev_state->type->width * 501 mdev_state->type->bytepp); 502 plane->size = mdev_state->memsize; 503 plane->region_index = MDPY_DISPLAY_REGION; 504 505 /* unused */ 506 plane->drm_format_mod = 0; 507 plane->x_pos = 0; 508 plane->y_pos = 0; 509 plane->x_hot = 0; 510 plane->y_hot = 0; 511 512 return 0; 513 } 514 515 static long mdpy_ioctl(struct vfio_device *vdev, unsigned int cmd, 516 unsigned long arg) 517 { 518 int ret = 0; 519 unsigned long minsz; 520 struct mdev_state *mdev_state = 521 container_of(vdev, struct mdev_state, vdev); 522 523 switch (cmd) { 524 case VFIO_DEVICE_GET_INFO: 525 { 526 struct vfio_device_info info; 527 528 minsz = offsetofend(struct vfio_device_info, num_irqs); 529 530 if (copy_from_user(&info, (void __user *)arg, minsz)) 531 return -EFAULT; 532 533 if (info.argsz < minsz) 534 return -EINVAL; 535 536 ret = mdpy_get_device_info(&info); 537 if (ret) 538 return ret; 539 540 memcpy(&mdev_state->dev_info, &info, sizeof(info)); 541 542 if (copy_to_user((void __user *)arg, &info, minsz)) 543 return -EFAULT; 544 545 return 0; 546 } 547 case VFIO_DEVICE_GET_REGION_INFO: 548 { 549 struct vfio_region_info info; 550 u16 cap_type_id = 0; 551 void *cap_type = NULL; 552 553 minsz = offsetofend(struct vfio_region_info, offset); 554 555 if (copy_from_user(&info, (void __user *)arg, minsz)) 556 return -EFAULT; 557 558 if (info.argsz < minsz) 559 return -EINVAL; 560 561 ret = mdpy_get_region_info(mdev_state, &info, &cap_type_id, 562 &cap_type); 563 if (ret) 564 return ret; 565 566 if (copy_to_user((void __user *)arg, &info, minsz)) 567 return -EFAULT; 568 569 return 0; 570 } 571 572 case VFIO_DEVICE_GET_IRQ_INFO: 573 { 574 struct vfio_irq_info info; 575 576 minsz = offsetofend(struct vfio_irq_info, count); 577 578 if (copy_from_user(&info, (void __user *)arg, minsz)) 579 return -EFAULT; 580 581 if ((info.argsz < minsz) || 582 (info.index >= mdev_state->dev_info.num_irqs)) 583 return -EINVAL; 584 585 ret = mdpy_get_irq_info(&info); 586 if (ret) 587 return ret; 588 589 if (copy_to_user((void __user *)arg, &info, minsz)) 590 return -EFAULT; 591 592 return 0; 593 } 594 595 case VFIO_DEVICE_QUERY_GFX_PLANE: 596 { 597 struct vfio_device_gfx_plane_info plane = {}; 598 599 minsz = offsetofend(struct vfio_device_gfx_plane_info, 600 region_index); 601 602 if (copy_from_user(&plane, (void __user *)arg, minsz)) 603 return -EFAULT; 604 605 if (plane.argsz < minsz) 606 return -EINVAL; 607 608 ret = mdpy_query_gfx_plane(mdev_state, &plane); 609 if (ret) 610 return ret; 611 612 if (copy_to_user((void __user *)arg, &plane, minsz)) 613 return -EFAULT; 614 615 return 0; 616 } 617 618 case VFIO_DEVICE_SET_IRQS: 619 return -EINVAL; 620 621 case VFIO_DEVICE_RESET: 622 return mdpy_reset(mdev_state); 623 } 624 return -ENOTTY; 625 } 626 627 static ssize_t 628 resolution_show(struct device *dev, struct device_attribute *attr, 629 char *buf) 630 { 631 struct mdev_state *mdev_state = dev_get_drvdata(dev); 632 633 return sprintf(buf, "%dx%d\n", 634 mdev_state->type->width, 635 mdev_state->type->height); 636 } 637 static DEVICE_ATTR_RO(resolution); 638 639 static struct attribute *mdev_dev_attrs[] = { 640 &dev_attr_resolution.attr, 641 NULL, 642 }; 643 644 static const struct attribute_group mdev_dev_group = { 645 .name = "vendor", 646 .attrs = mdev_dev_attrs, 647 }; 648 649 static const struct attribute_group *mdev_dev_groups[] = { 650 &mdev_dev_group, 651 NULL, 652 }; 653 654 static ssize_t mdpy_show_description(struct mdev_type *mtype, char *buf) 655 { 656 struct mdpy_type *type = container_of(mtype, struct mdpy_type, type); 657 658 return sprintf(buf, "virtual display, %dx%d framebuffer\n", 659 type->width, type->height); 660 } 661 662 static const struct vfio_device_ops mdpy_dev_ops = { 663 .init = mdpy_init_dev, 664 .release = mdpy_release_dev, 665 .read = mdpy_read, 666 .write = mdpy_write, 667 .ioctl = mdpy_ioctl, 668 .mmap = mdpy_mmap, 669 .bind_iommufd = vfio_iommufd_emulated_bind, 670 .unbind_iommufd = vfio_iommufd_emulated_unbind, 671 .attach_ioas = vfio_iommufd_emulated_attach_ioas, 672 .detach_ioas = vfio_iommufd_emulated_detach_ioas, 673 }; 674 675 static struct mdev_driver mdpy_driver = { 676 .device_api = VFIO_DEVICE_API_PCI_STRING, 677 .max_instances = 4, 678 .driver = { 679 .name = "mdpy", 680 .owner = THIS_MODULE, 681 .mod_name = KBUILD_MODNAME, 682 .dev_groups = mdev_dev_groups, 683 }, 684 .probe = mdpy_probe, 685 .remove = mdpy_remove, 686 .show_description = mdpy_show_description, 687 }; 688 689 static const struct file_operations vd_fops = { 690 .owner = THIS_MODULE, 691 }; 692 693 static void mdpy_device_release(struct device *dev) 694 { 695 /* nothing */ 696 } 697 698 static int __init mdpy_dev_init(void) 699 { 700 int ret = 0; 701 702 ret = alloc_chrdev_region(&mdpy_devt, 0, MINORMASK + 1, MDPY_NAME); 703 if (ret < 0) { 704 pr_err("Error: failed to register mdpy_dev, err: %d\n", ret); 705 return ret; 706 } 707 cdev_init(&mdpy_cdev, &vd_fops); 708 cdev_add(&mdpy_cdev, mdpy_devt, MINORMASK + 1); 709 pr_info("%s: major %d\n", __func__, MAJOR(mdpy_devt)); 710 711 ret = mdev_register_driver(&mdpy_driver); 712 if (ret) 713 goto err_cdev; 714 715 ret = class_register(&mdpy_class); 716 if (ret) 717 goto err_driver; 718 mdpy_dev.class = &mdpy_class; 719 mdpy_dev.release = mdpy_device_release; 720 dev_set_name(&mdpy_dev, "%s", MDPY_NAME); 721 722 ret = device_register(&mdpy_dev); 723 if (ret) 724 goto err_put; 725 726 ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver, 727 mdpy_mdev_types, 728 ARRAY_SIZE(mdpy_mdev_types)); 729 if (ret) 730 goto err_device; 731 732 return 0; 733 734 err_device: 735 device_del(&mdpy_dev); 736 err_put: 737 put_device(&mdpy_dev); 738 class_unregister(&mdpy_class); 739 err_driver: 740 mdev_unregister_driver(&mdpy_driver); 741 err_cdev: 742 cdev_del(&mdpy_cdev); 743 unregister_chrdev_region(mdpy_devt, MINORMASK + 1); 744 return ret; 745 } 746 747 static void __exit mdpy_dev_exit(void) 748 { 749 mdpy_dev.bus = NULL; 750 mdev_unregister_parent(&mdpy_parent); 751 752 device_unregister(&mdpy_dev); 753 mdev_unregister_driver(&mdpy_driver); 754 cdev_del(&mdpy_cdev); 755 unregister_chrdev_region(mdpy_devt, MINORMASK + 1); 756 class_unregister(&mdpy_class); 757 } 758 759 module_param_named(count, mdpy_driver.max_instances, int, 0444); 760 MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices"); 761 762 module_init(mdpy_dev_init) 763 module_exit(mdpy_dev_exit) 764