samples/vfio-mdev/mtty.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Mediated virtual PCI serial host device driver
   4  *
   5  * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
   6  *     Author: Neo Jia <cjia@nvidia.com>
   7  *             Kirti Wankhede <kwankhede@nvidia.com>
   8  *
   9  * Sample driver that creates mdev device that simulates serial port over PCI
  10  * card.
  11  */
  12
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15 #include <linux/kernel.h>
  16 #include <linux/fs.h>
  17 #include <linux/poll.h>
  18 #include <linux/slab.h>
  19 #include <linux/cdev.h>
  20 #include <linux/sched.h>
  21 #include <linux/wait.h>
  22 #include <linux/vfio.h>
  23 #include <linux/iommu.h>
  24 #include <linux/sysfs.h>
  25 #include <linux/ctype.h>
  26 #include <linux/file.h>
  27 #include <linux/mdev.h>
  28 #include <linux/pci.h>
  29 #include <linux/serial.h>
  30 #include <uapi/linux/serial_reg.h>
  31 #include <linux/eventfd.h>
  32 /*
  33  * #defines
  34  */
  35
  36 #define VERSION_STRING  "0.1"
  37 #define DRIVER_AUTHOR   "NVIDIA Corporation"
  38
  39 #define MTTY_CLASS_NAME "mtty"
  40
  41 #define MTTY_NAME       "mtty"
  42
  43 #define MTTY_STRING_LEN         16
  44
  45 #define MTTY_CONFIG_SPACE_SIZE  0xff
  46 #define MTTY_IO_BAR_SIZE        0x8
  47 #define MTTY_MMIO_BAR_SIZE      0x100000
  48
  49 #define STORE_LE16(addr, val)   (*(u16 *)addr = val)
  50 #define STORE_LE32(addr, val)   (*(u32 *)addr = val)
  51
  52 #define MAX_FIFO_SIZE   16
  53
  54 #define CIRCULAR_BUF_INC_IDX(idx)    (idx = (idx + 1) & (MAX_FIFO_SIZE - 1))
  55
  56 #define MTTY_VFIO_PCI_OFFSET_SHIFT   40
  57
  58 #define MTTY_VFIO_PCI_OFFSET_TO_INDEX(off)   (off >> MTTY_VFIO_PCI_OFFSET_SHIFT)
  59 #define MTTY_VFIO_PCI_INDEX_TO_OFFSET(index) \
  60                                 ((u64)(index) << MTTY_VFIO_PCI_OFFSET_SHIFT)
  61 #define MTTY_VFIO_PCI_OFFSET_MASK    \
  62                                 (((u64)(1) << MTTY_VFIO_PCI_OFFSET_SHIFT) - 1)
  63 #define MAX_MTTYS       24
  64
  65 /*
  66  * Global Structures
  67  */
  68
  69 static struct mtty_dev {
  70         dev_t           vd_devt;
  71         struct class    *vd_class;
  72         struct cdev     vd_cdev;
  73         struct idr      vd_idr;
  74         struct device   dev;
  75         struct mdev_parent parent;
  76 } mtty_dev;
  77
  78 struct mdev_region_info {
  79         u64 start;
  80         u64 phys_start;
  81         u32 size;
  82         u64 vfio_offset;
  83 };
  84
  85 #if defined(DEBUG_REGS)
  86 static const char *wr_reg[] = {
  87         "TX",
  88         "IER",
  89         "FCR",
  90         "LCR",
  91         "MCR",
  92         "LSR",
  93         "MSR",
  94         "SCR"
  95 };
  96
  97 static const char *rd_reg[] = {
  98         "RX",
  99         "IER",
 100         "IIR",
 101         "LCR",
 102         "MCR",
 103         "LSR",
 104         "MSR",
 105         "SCR"
 106 };
 107 #endif
 108
 109 /* loop back buffer */
 110 struct rxtx {
 111         u8 fifo[MAX_FIFO_SIZE];
 112         u8 head, tail;
 113         u8 count;
 114 };
 115
 116 struct serial_port {
 117         u8 uart_reg[8];         /* 8 registers */
 118         struct rxtx rxtx;       /* loop back buffer */
 119         bool dlab;
 120         bool overrun;
 121         u16 divisor;
 122         u8 fcr;                 /* FIFO control register */
 123         u8 max_fifo_size;
 124         u8 intr_trigger_level;  /* interrupt trigger level */
 125 };
 126
 127 /* State of each mdev device */
 128 struct mdev_state {
 129         struct vfio_device vdev;
 130         int irq_fd;
 131         struct eventfd_ctx *intx_evtfd;
 132         struct eventfd_ctx *msi_evtfd;
 133         int irq_index;
 134         u8 *vconfig;
 135         struct mutex ops_lock;
 136         struct mdev_device *mdev;
 137         struct mdev_region_info region_info[VFIO_PCI_NUM_REGIONS];
 138         u32 bar_mask[VFIO_PCI_NUM_REGIONS];
 139         struct list_head next;
 140         struct serial_port s[2];
 141         struct mutex rxtx_lock;
 142         struct vfio_device_info dev_info;
 143         int nr_ports;
 144 };
 145
 146 static struct mtty_type {
 147         struct mdev_type type;
 148         int nr_ports;
 149 } mtty_types[2] = {
 150         { .nr_ports = 1, .type.sysfs_name = "1",
 151           .type.pretty_name = "Single port serial" },
 152         { .nr_ports = 2, .type.sysfs_name = "2",
 153           .type.pretty_name = "Dual port serial" },
 154 };
 155
 156 static struct mdev_type *mtty_mdev_types[] = {
 157         &mtty_types[0].type,
 158         &mtty_types[1].type,
 159 };
 160
 161 static atomic_t mdev_avail_ports = ATOMIC_INIT(MAX_MTTYS);
 162
 163 static const struct file_operations vd_fops = {
 164         .owner          = THIS_MODULE,
 165 };
 166
 167 static const struct vfio_device_ops mtty_dev_ops;
 168
 169 /* function prototypes */
 170
 171 static int mtty_trigger_interrupt(struct mdev_state *mdev_state);
 172
 173 /* Helper functions */
 174
 175 static void dump_buffer(u8 *buf, uint32_t count)
 176 {
 177 #if defined(DEBUG)
 178         int i;
 179
 180         pr_info("Buffer:\n");
 181         for (i = 0; i < count; i++) {
 182                 pr_info("%2x ", *(buf + i));
 183                 if ((i + 1) % 16 == 0)
 184                         pr_info("\n");
 185         }
 186 #endif
 187 }
 188
 189 static void mtty_create_config_space(struct mdev_state *mdev_state)
 190 {
 191         /* PCI dev ID */
 192         STORE_LE32((u32 *) &mdev_state->vconfig[0x0], 0x32534348);
 193
 194         /* Control: I/O+, Mem-, BusMaster- */
 195         STORE_LE16((u16 *) &mdev_state->vconfig[0x4], 0x0001);
 196
 197         /* Status: capabilities list absent */
 198         STORE_LE16((u16 *) &mdev_state->vconfig[0x6], 0x0200);
 199
 200         /* Rev ID */
 201         mdev_state->vconfig[0x8] =  0x10;
 202
 203         /* programming interface class : 16550-compatible serial controller */
 204         mdev_state->vconfig[0x9] =  0x02;
 205
 206         /* Sub class : 00 */
 207         mdev_state->vconfig[0xa] =  0x00;
 208
 209         /* Base class : Simple Communication controllers */
 210         mdev_state->vconfig[0xb] =  0x07;
 211
 212         /* base address registers */
 213         /* BAR0: IO space */
 214         STORE_LE32((u32 *) &mdev_state->vconfig[0x10], 0x000001);
 215         mdev_state->bar_mask[0] = ~(MTTY_IO_BAR_SIZE) + 1;
 216
 217         if (mdev_state->nr_ports == 2) {
 218                 /* BAR1: IO space */
 219                 STORE_LE32((u32 *) &mdev_state->vconfig[0x14], 0x000001);
 220                 mdev_state->bar_mask[1] = ~(MTTY_IO_BAR_SIZE) + 1;
 221         }
 222
 223         /* Subsystem ID */
 224         STORE_LE32((u32 *) &mdev_state->vconfig[0x2c], 0x32534348);
 225
 226         mdev_state->vconfig[0x34] =  0x00;   /* Cap Ptr */
 227         mdev_state->vconfig[0x3d] =  0x01;   /* interrupt pin (INTA#) */
 228
 229         /* Vendor specific data */
 230         mdev_state->vconfig[0x40] =  0x23;
 231         mdev_state->vconfig[0x43] =  0x80;
 232         mdev_state->vconfig[0x44] =  0x23;
 233         mdev_state->vconfig[0x48] =  0x23;
 234         mdev_state->vconfig[0x4c] =  0x23;
 235
 236         mdev_state->vconfig[0x60] =  0x50;
 237         mdev_state->vconfig[0x61] =  0x43;
 238         mdev_state->vconfig[0x62] =  0x49;
 239         mdev_state->vconfig[0x63] =  0x20;
 240         mdev_state->vconfig[0x64] =  0x53;
 241         mdev_state->vconfig[0x65] =  0x65;
 242         mdev_state->vconfig[0x66] =  0x72;
 243         mdev_state->vconfig[0x67] =  0x69;
 244         mdev_state->vconfig[0x68] =  0x61;
 245         mdev_state->vconfig[0x69] =  0x6c;
 246         mdev_state->vconfig[0x6a] =  0x2f;
 247         mdev_state->vconfig[0x6b] =  0x55;
 248         mdev_state->vconfig[0x6c] =  0x41;
 249         mdev_state->vconfig[0x6d] =  0x52;
 250         mdev_state->vconfig[0x6e] =  0x54;
 251 }
 252
 253 static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
 254                                  u8 *buf, u32 count)
 255 {
 256         u32 cfg_addr, bar_mask, bar_index = 0;
 257
 258         switch (offset) {
 259         case 0x04: /* device control */
 260         case 0x06: /* device status */
 261                 /* do nothing */
 262                 break;
 263         case 0x3c:  /* interrupt line */
 264                 mdev_state->vconfig[0x3c] = buf[0];
 265                 break;
 266         case 0x3d:
 267                 /*
 268                  * Interrupt Pin is hardwired to INTA.
 269                  * This field is write protected by hardware
 270                  */
 271                 break;
 272         case 0x10:  /* BAR0 */
 273         case 0x14:  /* BAR1 */
 274                 if (offset == 0x10)
 275                         bar_index = 0;
 276                 else if (offset == 0x14)
 277                         bar_index = 1;
 278
 279                 if ((mdev_state->nr_ports == 1) && (bar_index == 1)) {
 280                         STORE_LE32(&mdev_state->vconfig[offset], 0);
 281                         break;
 282                 }
 283
 284                 cfg_addr = *(u32 *)buf;
 285                 pr_info("BAR%d addr 0x%x\n", bar_index, cfg_addr);
 286
 287                 if (cfg_addr == 0xffffffff) {
 288                         bar_mask = mdev_state->bar_mask[bar_index];
 289                         cfg_addr = (cfg_addr & bar_mask);
 290                 }
 291
 292                 cfg_addr |= (mdev_state->vconfig[offset] & 0x3ul);
 293                 STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
 294                 break;
 295         case 0x18:  /* BAR2 */
 296         case 0x1c:  /* BAR3 */
 297         case 0x20:  /* BAR4 */
 298                 STORE_LE32(&mdev_state->vconfig[offset], 0);
 299                 break;
 300         default:
 301                 pr_info("PCI config write @0x%x of %d bytes not handled\n",
 302                         offset, count);
 303                 break;
 304         }
 305 }
 306
 307 static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
 308                                 u16 offset, u8 *buf, u32 count)
 309 {
 310         u8 data = *buf;
 311
 312         /* Handle data written by guest */
 313         switch (offset) {
 314         case UART_TX:
 315                 /* if DLAB set, data is LSB of divisor */
 316                 if (mdev_state->s[index].dlab) {
 317                         mdev_state->s[index].divisor |= data;
 318                         break;
 319                 }
 320
 321                 mutex_lock(&mdev_state->rxtx_lock);
 322
 323                 /* save in TX buffer */
 324                 if (mdev_state->s[index].rxtx.count <
 325                                 mdev_state->s[index].max_fifo_size) {
 326                         mdev_state->s[index].rxtx.fifo[
 327                                         mdev_state->s[index].rxtx.head] = data;
 328                         mdev_state->s[index].rxtx.count++;
 329                         CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.head);
 330                         mdev_state->s[index].overrun = false;
 331
 332                         /*
 333                          * Trigger interrupt if receive data interrupt is
 334                          * enabled and fifo reached trigger level
 335                          */
 336                         if ((mdev_state->s[index].uart_reg[UART_IER] &
 337                                                 UART_IER_RDI) &&
 338                            (mdev_state->s[index].rxtx.count ==
 339                                     mdev_state->s[index].intr_trigger_level)) {
 340                                 /* trigger interrupt */
 341 #if defined(DEBUG_INTR)
 342                                 pr_err("Serial port %d: Fifo level trigger\n",
 343                                         index);
 344 #endif
 345                                 mtty_trigger_interrupt(mdev_state);
 346                         }
 347                 } else {
 348 #if defined(DEBUG_INTR)
 349                         pr_err("Serial port %d: Buffer Overflow\n", index);
 350 #endif
 351                         mdev_state->s[index].overrun = true;
 352
 353                         /*
 354                          * Trigger interrupt if receiver line status interrupt
 355                          * is enabled
 356                          */
 357                         if (mdev_state->s[index].uart_reg[UART_IER] &
 358                                                                 UART_IER_RLSI)
 359                                 mtty_trigger_interrupt(mdev_state);
 360                 }
 361                 mutex_unlock(&mdev_state->rxtx_lock);
 362                 break;
 363
 364         case UART_IER:
 365                 /* if DLAB set, data is MSB of divisor */
 366                 if (mdev_state->s[index].dlab)
 367                         mdev_state->s[index].divisor |= (u16)data << 8;
 368                 else {
 369                         mdev_state->s[index].uart_reg[offset] = data;
 370                         mutex_lock(&mdev_state->rxtx_lock);
 371                         if ((data & UART_IER_THRI) &&
 372                             (mdev_state->s[index].rxtx.head ==
 373                                         mdev_state->s[index].rxtx.tail)) {
 374 #if defined(DEBUG_INTR)
 375                                 pr_err("Serial port %d: IER_THRI write\n",
 376                                         index);
 377 #endif
 378                                 mtty_trigger_interrupt(mdev_state);
 379                         }
 380
 381                         mutex_unlock(&mdev_state->rxtx_lock);
 382                 }
 383
 384                 break;
 385
 386         case UART_FCR:
 387                 mdev_state->s[index].fcr = data;
 388
 389                 mutex_lock(&mdev_state->rxtx_lock);
 390                 if (data & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT)) {
 391                         /* clear loop back FIFO */
 392                         mdev_state->s[index].rxtx.count = 0;
 393                         mdev_state->s[index].rxtx.head = 0;
 394                         mdev_state->s[index].rxtx.tail = 0;
 395                 }
 396                 mutex_unlock(&mdev_state->rxtx_lock);
 397
 398                 switch (data & UART_FCR_TRIGGER_MASK) {
 399                 case UART_FCR_TRIGGER_1:
 400                         mdev_state->s[index].intr_trigger_level = 1;
 401                         break;
 402
 403                 case UART_FCR_TRIGGER_4:
 404                         mdev_state->s[index].intr_trigger_level = 4;
 405                         break;
 406
 407                 case UART_FCR_TRIGGER_8:
 408                         mdev_state->s[index].intr_trigger_level = 8;
 409                         break;
 410
 411                 case UART_FCR_TRIGGER_14:
 412                         mdev_state->s[index].intr_trigger_level = 14;
 413                         break;
 414                 }
 415
 416                 /*
 417                  * Set trigger level to 1 otherwise or  implement timer with
 418                  * timeout of 4 characters and on expiring that timer set
 419                  * Recevice data timeout in IIR register
 420                  */
 421                 mdev_state->s[index].intr_trigger_level = 1;
 422                 if (data & UART_FCR_ENABLE_FIFO)
 423                         mdev_state->s[index].max_fifo_size = MAX_FIFO_SIZE;
 424                 else {
 425                         mdev_state->s[index].max_fifo_size = 1;
 426                         mdev_state->s[index].intr_trigger_level = 1;
 427                 }
 428
 429                 break;
 430
 431         case UART_LCR:
 432                 if (data & UART_LCR_DLAB) {
 433                         mdev_state->s[index].dlab = true;
 434                         mdev_state->s[index].divisor = 0;
 435                 } else
 436                         mdev_state->s[index].dlab = false;
 437
 438                 mdev_state->s[index].uart_reg[offset] = data;
 439                 break;
 440
 441         case UART_MCR:
 442                 mdev_state->s[index].uart_reg[offset] = data;
 443
 444                 if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
 445                                 (data & UART_MCR_OUT2)) {
 446 #if defined(DEBUG_INTR)
 447                         pr_err("Serial port %d: MCR_OUT2 write\n", index);
 448 #endif
 449                         mtty_trigger_interrupt(mdev_state);
 450                 }
 451
 452                 if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
 453                                 (data & (UART_MCR_RTS | UART_MCR_DTR))) {
 454 #if defined(DEBUG_INTR)
 455                         pr_err("Serial port %d: MCR RTS/DTR write\n", index);
 456 #endif
 457                         mtty_trigger_interrupt(mdev_state);
 458                 }
 459                 break;
 460
 461         case UART_LSR:
 462         case UART_MSR:
 463                 /* do nothing */
 464                 break;
 465
 466         case UART_SCR:
 467                 mdev_state->s[index].uart_reg[offset] = data;
 468                 break;
 469
 470         default:
 471                 break;
 472         }
 473 }
 474
 475 static void handle_bar_read(unsigned int index, struct mdev_state *mdev_state,
 476                             u16 offset, u8 *buf, u32 count)
 477 {
 478         /* Handle read requests by guest */
 479         switch (offset) {
 480         case UART_RX:
 481                 /* if DLAB set, data is LSB of divisor */
 482                 if (mdev_state->s[index].dlab) {
 483                         *buf  = (u8)mdev_state->s[index].divisor;
 484                         break;
 485                 }
 486
 487                 mutex_lock(&mdev_state->rxtx_lock);
 488                 /* return data in tx buffer */
 489                 if (mdev_state->s[index].rxtx.head !=
 490                                  mdev_state->s[index].rxtx.tail) {
 491                         *buf = mdev_state->s[index].rxtx.fifo[
 492                                                 mdev_state->s[index].rxtx.tail];
 493                         mdev_state->s[index].rxtx.count--;
 494                         CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.tail);
 495                 }
 496
 497                 if (mdev_state->s[index].rxtx.head ==
 498                                 mdev_state->s[index].rxtx.tail) {
 499                 /*
 500                  *  Trigger interrupt if tx buffer empty interrupt is
 501                  *  enabled and fifo is empty
 502                  */
 503 #if defined(DEBUG_INTR)
 504                         pr_err("Serial port %d: Buffer Empty\n", index);
 505 #endif
 506                         if (mdev_state->s[index].uart_reg[UART_IER] &
 507                                                          UART_IER_THRI)
 508                                 mtty_trigger_interrupt(mdev_state);
 509                 }
 510                 mutex_unlock(&mdev_state->rxtx_lock);
 511
 512                 break;
 513
 514         case UART_IER:
 515                 if (mdev_state->s[index].dlab) {
 516                         *buf = (u8)(mdev_state->s[index].divisor >> 8);
 517                         break;
 518                 }
 519                 *buf = mdev_state->s[index].uart_reg[offset] & 0x0f;
 520                 break;
 521
 522         case UART_IIR:
 523         {
 524                 u8 ier = mdev_state->s[index].uart_reg[UART_IER];
 525                 *buf = 0;
 526
 527                 mutex_lock(&mdev_state->rxtx_lock);
 528                 /* Interrupt priority 1: Parity, overrun, framing or break */
 529                 if ((ier & UART_IER_RLSI) && mdev_state->s[index].overrun)
 530                         *buf |= UART_IIR_RLSI;
 531
 532                 /* Interrupt priority 2: Fifo trigger level reached */
 533                 if ((ier & UART_IER_RDI) &&
 534                     (mdev_state->s[index].rxtx.count >=
 535                       mdev_state->s[index].intr_trigger_level))
 536                         *buf |= UART_IIR_RDI;
 537
 538                 /* Interrupt priotiry 3: transmitter holding register empty */
 539                 if ((ier & UART_IER_THRI) &&
 540                     (mdev_state->s[index].rxtx.head ==
 541                                 mdev_state->s[index].rxtx.tail))
 542                         *buf |= UART_IIR_THRI;
 543
 544                 /* Interrupt priotiry 4: Modem status: CTS, DSR, RI or DCD  */
 545                 if ((ier & UART_IER_MSI) &&
 546                     (mdev_state->s[index].uart_reg[UART_MCR] &
 547                                  (UART_MCR_RTS | UART_MCR_DTR)))
 548                         *buf |= UART_IIR_MSI;
 549
 550                 /* bit0: 0=> interrupt pending, 1=> no interrupt is pending */
 551                 if (*buf == 0)
 552                         *buf = UART_IIR_NO_INT;
 553
 554                 /* set bit 6 & 7 to be 16550 compatible */
 555                 *buf |= 0xC0;
 556                 mutex_unlock(&mdev_state->rxtx_lock);
 557         }
 558         break;
 559
 560         case UART_LCR:
 561         case UART_MCR:
 562                 *buf = mdev_state->s[index].uart_reg[offset];
 563                 break;
 564
 565         case UART_LSR:
 566         {
 567                 u8 lsr = 0;
 568
 569                 mutex_lock(&mdev_state->rxtx_lock);
 570                 /* atleast one char in FIFO */
 571                 if (mdev_state->s[index].rxtx.head !=
 572                                  mdev_state->s[index].rxtx.tail)
 573                         lsr |= UART_LSR_DR;
 574
 575                 /* if FIFO overrun */
 576                 if (mdev_state->s[index].overrun)
 577                         lsr |= UART_LSR_OE;
 578
 579                 /* transmit FIFO empty and tramsitter empty */
 580                 if (mdev_state->s[index].rxtx.head ==
 581                                  mdev_state->s[index].rxtx.tail)
 582                         lsr |= UART_LSR_TEMT | UART_LSR_THRE;
 583
 584                 mutex_unlock(&mdev_state->rxtx_lock);
 585                 *buf = lsr;
 586                 break;
 587         }
 588         case UART_MSR:
 589                 *buf = UART_MSR_DSR | UART_MSR_DDSR | UART_MSR_DCD;
 590
 591                 mutex_lock(&mdev_state->rxtx_lock);
 592                 /* if AFE is 1 and FIFO have space, set CTS bit */
 593                 if (mdev_state->s[index].uart_reg[UART_MCR] &
 594                                                  UART_MCR_AFE) {
 595                         if (mdev_state->s[index].rxtx.count <
 596                                         mdev_state->s[index].max_fifo_size)
 597                                 *buf |= UART_MSR_CTS | UART_MSR_DCTS;
 598                 } else
 599                         *buf |= UART_MSR_CTS | UART_MSR_DCTS;
 600                 mutex_unlock(&mdev_state->rxtx_lock);
 601
 602                 break;
 603
 604         case UART_SCR:
 605                 *buf = mdev_state->s[index].uart_reg[offset];
 606                 break;
 607
 608         default:
 609                 break;
 610         }
 611 }
 612
 613 static void mdev_read_base(struct mdev_state *mdev_state)
 614 {
 615         int index, pos;
 616         u32 start_lo, start_hi;
 617         u32 mem_type;
 618
 619         pos = PCI_BASE_ADDRESS_0;
 620
 621         for (index = 0; index <= VFIO_PCI_BAR5_REGION_INDEX; index++) {
 622
 623                 if (!mdev_state->region_info[index].size)
 624                         continue;
 625
 626                 start_lo = (*(u32 *)(mdev_state->vconfig + pos)) &
 627                         PCI_BASE_ADDRESS_MEM_MASK;
 628                 mem_type = (*(u32 *)(mdev_state->vconfig + pos)) &
 629                         PCI_BASE_ADDRESS_MEM_TYPE_MASK;
 630
 631                 switch (mem_type) {
 632                 case PCI_BASE_ADDRESS_MEM_TYPE_64:
 633                         start_hi = (*(u32 *)(mdev_state->vconfig + pos + 4));
 634                         pos += 4;
 635                         break;
 636                 case PCI_BASE_ADDRESS_MEM_TYPE_32:
 637                 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
 638                         /* 1M mem BAR treated as 32-bit BAR */
 639                 default:
 640                         /* mem unknown type treated as 32-bit BAR */
 641                         start_hi = 0;
 642                         break;
 643                 }
 644                 pos += 4;
 645                 mdev_state->region_info[index].start = ((u64)start_hi << 32) |
 646                                                         start_lo;
 647         }
 648 }
 649
 650 static ssize_t mdev_access(struct mdev_state *mdev_state, u8 *buf, size_t count,
 651                            loff_t pos, bool is_write)
 652 {
 653         unsigned int index;
 654         loff_t offset;
 655         int ret = 0;
 656
 657         if (!buf)
 658                 return -EINVAL;
 659
 660         mutex_lock(&mdev_state->ops_lock);
 661
 662         index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(pos);
 663         offset = pos & MTTY_VFIO_PCI_OFFSET_MASK;
 664         switch (index) {
 665         case VFIO_PCI_CONFIG_REGION_INDEX:
 666
 667 #if defined(DEBUG)
 668                 pr_info("%s: PCI config space %s at offset 0x%llx\n",
 669                          __func__, is_write ? "write" : "read", offset);
 670 #endif
 671                 if (is_write) {
 672                         dump_buffer(buf, count);
 673                         handle_pci_cfg_write(mdev_state, offset, buf, count);
 674                 } else {
 675                         memcpy(buf, (mdev_state->vconfig + offset), count);
 676                         dump_buffer(buf, count);
 677                 }
 678
 679                 break;
 680
 681         case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
 682                 if (!mdev_state->region_info[index].start)
 683                         mdev_read_base(mdev_state);
 684
 685                 if (is_write) {
 686                         dump_buffer(buf, count);
 687
 688 #if defined(DEBUG_REGS)
 689                         pr_info("%s: BAR%d  WR @0x%llx %s val:0x%02x dlab:%d\n",
 690                                 __func__, index, offset, wr_reg[offset],
 691                                 *buf, mdev_state->s[index].dlab);
 692 #endif
 693                         handle_bar_write(index, mdev_state, offset, buf, count);
 694                 } else {
 695                         handle_bar_read(index, mdev_state, offset, buf, count);
 696                         dump_buffer(buf, count);
 697
 698 #if defined(DEBUG_REGS)
 699                         pr_info("%s: BAR%d  RD @0x%llx %s val:0x%02x dlab:%d\n",
 700                                 __func__, index, offset, rd_reg[offset],
 701                                 *buf, mdev_state->s[index].dlab);
 702 #endif
 703                 }
 704                 break;
 705
 706         default:
 707                 ret = -1;
 708                 goto accessfailed;
 709         }
 710
 711         ret = count;
 712
 713
 714 accessfailed:
 715         mutex_unlock(&mdev_state->ops_lock);
 716
 717         return ret;
 718 }
 719
 720 static int mtty_init_dev(struct vfio_device *vdev)
 721 {
 722         struct mdev_state *mdev_state =
 723                 container_of(vdev, struct mdev_state, vdev);
 724         struct mdev_device *mdev = to_mdev_device(vdev->dev);
 725         struct mtty_type *type =
 726                 container_of(mdev->type, struct mtty_type, type);
 727         int avail_ports = atomic_read(&mdev_avail_ports);
 728         int ret;
 729
 730         do {
 731                 if (avail_ports < type->nr_ports)
 732                         return -ENOSPC;
 733         } while (!atomic_try_cmpxchg(&mdev_avail_ports,
 734                                      &avail_ports,
 735                                      avail_ports - type->nr_ports));
 736
 737         mdev_state->nr_ports = type->nr_ports;
 738         mdev_state->irq_index = -1;
 739         mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
 740         mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
 741         mutex_init(&mdev_state->rxtx_lock);
 742
 743         mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
 744         if (!mdev_state->vconfig) {
 745                 ret = -ENOMEM;
 746                 goto err_nr_ports;
 747         }
 748
 749         mutex_init(&mdev_state->ops_lock);
 750         mdev_state->mdev = mdev;
 751         mtty_create_config_space(mdev_state);
 752         return 0;
 753
 754 err_nr_ports:
 755         atomic_add(type->nr_ports, &mdev_avail_ports);
 756         return ret;
 757 }
 758
 759 static int mtty_probe(struct mdev_device *mdev)
 760 {
 761         struct mdev_state *mdev_state;
 762         int ret;
 763
 764         mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev,
 765                                        &mtty_dev_ops);
 766         if (IS_ERR(mdev_state))
 767                 return PTR_ERR(mdev_state);
 768
 769         ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
 770         if (ret)
 771                 goto err_put_vdev;
 772         dev_set_drvdata(&mdev->dev, mdev_state);
 773         return 0;
 774
 775 err_put_vdev:
 776         vfio_put_device(&mdev_state->vdev);
 777         return ret;
 778 }
 779
 780 static void mtty_release_dev(struct vfio_device *vdev)
 781 {
 782         struct mdev_state *mdev_state =
 783                 container_of(vdev, struct mdev_state, vdev);
 784
 785         atomic_add(mdev_state->nr_ports, &mdev_avail_ports);
 786         kfree(mdev_state->vconfig);
 787 }
 788
 789 static void mtty_remove(struct mdev_device *mdev)
 790 {
 791         struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
 792
 793         vfio_unregister_group_dev(&mdev_state->vdev);
 794         vfio_put_device(&mdev_state->vdev);
 795 }
 796
 797 static int mtty_reset(struct mdev_state *mdev_state)
 798 {
 799         pr_info("%s: called\n", __func__);
 800
 801         return 0;
 802 }
 803
 804 static ssize_t mtty_read(struct vfio_device *vdev, char __user *buf,
 805                          size_t count, loff_t *ppos)
 806 {
 807         struct mdev_state *mdev_state =
 808                 container_of(vdev, struct mdev_state, vdev);
 809         unsigned int done = 0;
 810         int ret;
 811
 812         while (count) {
 813                 size_t filled;
 814
 815                 if (count >= 4 && !(*ppos % 4)) {
 816                         u32 val;
 817
 818                         ret =  mdev_access(mdev_state, (u8 *)&val, sizeof(val),
 819                                            *ppos, false);
 820                         if (ret <= 0)
 821                                 goto read_err;
 822
 823                         if (copy_to_user(buf, &val, sizeof(val)))
 824                                 goto read_err;
 825
 826                         filled = 4;
 827                 } else if (count >= 2 && !(*ppos % 2)) {
 828                         u16 val;
 829
 830                         ret = mdev_access(mdev_state, (u8 *)&val, sizeof(val),
 831                                           *ppos, false);
 832                         if (ret <= 0)
 833                                 goto read_err;
 834
 835                         if (copy_to_user(buf, &val, sizeof(val)))
 836                                 goto read_err;
 837
 838                         filled = 2;
 839                 } else {
 840                         u8 val;
 841
 842                         ret = mdev_access(mdev_state, (u8 *)&val, sizeof(val),
 843                                           *ppos, false);
 844                         if (ret <= 0)
 845                                 goto read_err;
 846
 847                         if (copy_to_user(buf, &val, sizeof(val)))
 848                                 goto read_err;
 849
 850                         filled = 1;
 851                 }
 852
 853                 count -= filled;
 854                 done += filled;
 855                 *ppos += filled;
 856                 buf += filled;
 857         }
 858
 859         return done;
 860
 861 read_err:
 862         return -EFAULT;
 863 }
 864
 865 static ssize_t mtty_write(struct vfio_device *vdev, const char __user *buf,
 866                    size_t count, loff_t *ppos)
 867 {
 868         struct mdev_state *mdev_state =
 869                 container_of(vdev, struct mdev_state, vdev);
 870         unsigned int done = 0;
 871         int ret;
 872
 873         while (count) {
 874                 size_t filled;
 875
 876                 if (count >= 4 && !(*ppos % 4)) {
 877                         u32 val;
 878
 879                         if (copy_from_user(&val, buf, sizeof(val)))
 880                                 goto write_err;
 881
 882                         ret = mdev_access(mdev_state, (u8 *)&val, sizeof(val),
 883                                           *ppos, true);
 884                         if (ret <= 0)
 885                                 goto write_err;
 886
 887                         filled = 4;
 888                 } else if (count >= 2 && !(*ppos % 2)) {
 889                         u16 val;
 890
 891                         if (copy_from_user(&val, buf, sizeof(val)))
 892                                 goto write_err;
 893
 894                         ret = mdev_access(mdev_state, (u8 *)&val, sizeof(val),
 895                                           *ppos, true);
 896                         if (ret <= 0)
 897                                 goto write_err;
 898
 899                         filled = 2;
 900                 } else {
 901                         u8 val;
 902
 903                         if (copy_from_user(&val, buf, sizeof(val)))
 904                                 goto write_err;
 905
 906                         ret = mdev_access(mdev_state, (u8 *)&val, sizeof(val),
 907                                           *ppos, true);
 908                         if (ret <= 0)
 909                                 goto write_err;
 910
 911                         filled = 1;
 912                 }
 913                 count -= filled;
 914                 done += filled;
 915                 *ppos += filled;
 916                 buf += filled;
 917         }
 918
 919         return done;
 920 write_err:
 921         return -EFAULT;
 922 }
 923
 924 static int mtty_set_irqs(struct mdev_state *mdev_state, uint32_t flags,
 925                          unsigned int index, unsigned int start,
 926                          unsigned int count, void *data)
 927 {
 928         int ret = 0;
 929
 930         mutex_lock(&mdev_state->ops_lock);
 931         switch (index) {
 932         case VFIO_PCI_INTX_IRQ_INDEX:
 933                 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 934                 case VFIO_IRQ_SET_ACTION_MASK:
 935                 case VFIO_IRQ_SET_ACTION_UNMASK:
 936                         break;
 937                 case VFIO_IRQ_SET_ACTION_TRIGGER:
 938                 {
 939                         if (flags & VFIO_IRQ_SET_DATA_NONE) {
 940                                 pr_info("%s: disable INTx\n", __func__);
 941                                 if (mdev_state->intx_evtfd)
 942                                         eventfd_ctx_put(mdev_state->intx_evtfd);
 943                                 break;
 944                         }
 945
 946                         if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 947                                 int fd = *(int *)data;
 948
 949                                 if (fd > 0) {
 950                                         struct eventfd_ctx *evt;
 951
 952                                         evt = eventfd_ctx_fdget(fd);
 953                                         if (IS_ERR(evt)) {
 954                                                 ret = PTR_ERR(evt);
 955                                                 break;
 956                                         }
 957                                         mdev_state->intx_evtfd = evt;
 958                                         mdev_state->irq_fd = fd;
 959                                         mdev_state->irq_index = index;
 960                                         break;
 961                                 }
 962                         }
 963                         break;
 964                 }
 965                 }
 966                 break;
 967         case VFIO_PCI_MSI_IRQ_INDEX:
 968                 switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 969                 case VFIO_IRQ_SET_ACTION_MASK:
 970                 case VFIO_IRQ_SET_ACTION_UNMASK:
 971                         break;
 972                 case VFIO_IRQ_SET_ACTION_TRIGGER:
 973                         if (flags & VFIO_IRQ_SET_DATA_NONE) {
 974                                 if (mdev_state->msi_evtfd)
 975                                         eventfd_ctx_put(mdev_state->msi_evtfd);
 976                                 pr_info("%s: disable MSI\n", __func__);
 977                                 mdev_state->irq_index = VFIO_PCI_INTX_IRQ_INDEX;
 978                                 break;
 979                         }
 980                         if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 981                                 int fd = *(int *)data;
 982                                 struct eventfd_ctx *evt;
 983
 984                                 if (fd <= 0)
 985                                         break;
 986
 987                                 if (mdev_state->msi_evtfd)
 988                                         break;
 989
 990                                 evt = eventfd_ctx_fdget(fd);
 991                                 if (IS_ERR(evt)) {
 992                                         ret = PTR_ERR(evt);
 993                                         break;
 994                                 }
 995                                 mdev_state->msi_evtfd = evt;
 996                                 mdev_state->irq_fd = fd;
 997                                 mdev_state->irq_index = index;
 998                         }
 999                         break;
1000         }
1001         break;
1002         case VFIO_PCI_MSIX_IRQ_INDEX:
1003                 pr_info("%s: MSIX_IRQ\n", __func__);
1004                 break;
1005         case VFIO_PCI_ERR_IRQ_INDEX:
1006                 pr_info("%s: ERR_IRQ\n", __func__);
1007                 break;
1008         case VFIO_PCI_REQ_IRQ_INDEX:
1009                 pr_info("%s: REQ_IRQ\n", __func__);
1010                 break;
1011         }
1012
1013         mutex_unlock(&mdev_state->ops_lock);
1014         return ret;
1015 }
1016
1017 static int mtty_trigger_interrupt(struct mdev_state *mdev_state)
1018 {
1019         int ret = -1;
1020
1021         if ((mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX) &&
1022             (!mdev_state->msi_evtfd))
1023                 return -EINVAL;
1024         else if ((mdev_state->irq_index == VFIO_PCI_INTX_IRQ_INDEX) &&
1025                  (!mdev_state->intx_evtfd)) {
1026                 pr_info("%s: Intr eventfd not found\n", __func__);
1027                 return -EINVAL;
1028         }
1029
1030         if (mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX)
1031                 ret = eventfd_signal(mdev_state->msi_evtfd, 1);
1032         else
1033                 ret = eventfd_signal(mdev_state->intx_evtfd, 1);
1034
1035 #if defined(DEBUG_INTR)
1036         pr_info("Intx triggered\n");
1037 #endif
1038         if (ret != 1)
1039                 pr_err("%s: eventfd signal failed (%d)\n", __func__, ret);
1040
1041         return ret;
1042 }
1043
1044 static int mtty_get_region_info(struct mdev_state *mdev_state,
1045                          struct vfio_region_info *region_info,
1046                          u16 *cap_type_id, void **cap_type)
1047 {
1048         unsigned int size = 0;
1049         u32 bar_index;
1050
1051         bar_index = region_info->index;
1052         if (bar_index >= VFIO_PCI_NUM_REGIONS)
1053                 return -EINVAL;
1054
1055         mutex_lock(&mdev_state->ops_lock);
1056
1057         switch (bar_index) {
1058         case VFIO_PCI_CONFIG_REGION_INDEX:
1059                 size = MTTY_CONFIG_SPACE_SIZE;
1060                 break;
1061         case VFIO_PCI_BAR0_REGION_INDEX:
1062                 size = MTTY_IO_BAR_SIZE;
1063                 break;
1064         case VFIO_PCI_BAR1_REGION_INDEX:
1065                 if (mdev_state->nr_ports == 2)
1066                         size = MTTY_IO_BAR_SIZE;
1067                 break;
1068         default:
1069                 size = 0;
1070                 break;
1071         }
1072
1073         mdev_state->region_info[bar_index].size = size;
1074         mdev_state->region_info[bar_index].vfio_offset =
1075                 MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
1076
1077         region_info->size = size;
1078         region_info->offset = MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
1079         region_info->flags = VFIO_REGION_INFO_FLAG_READ |
1080                 VFIO_REGION_INFO_FLAG_WRITE;
1081         mutex_unlock(&mdev_state->ops_lock);
1082         return 0;
1083 }
1084
1085 static int mtty_get_irq_info(struct vfio_irq_info *irq_info)
1086 {
1087         switch (irq_info->index) {
1088         case VFIO_PCI_INTX_IRQ_INDEX:
1089         case VFIO_PCI_MSI_IRQ_INDEX:
1090         case VFIO_PCI_REQ_IRQ_INDEX:
1091                 break;
1092
1093         default:
1094                 return -EINVAL;
1095         }
1096
1097         irq_info->flags = VFIO_IRQ_INFO_EVENTFD;
1098         irq_info->count = 1;
1099
1100         if (irq_info->index == VFIO_PCI_INTX_IRQ_INDEX)
1101                 irq_info->flags |= (VFIO_IRQ_INFO_MASKABLE |
1102                                 VFIO_IRQ_INFO_AUTOMASKED);
1103         else
1104                 irq_info->flags |= VFIO_IRQ_INFO_NORESIZE;
1105
1106         return 0;
1107 }
1108
1109 static int mtty_get_device_info(struct vfio_device_info *dev_info)
1110 {
1111         dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
1112         dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
1113         dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
1114
1115         return 0;
1116 }
1117
1118 static long mtty_ioctl(struct vfio_device *vdev, unsigned int cmd,
1119                         unsigned long arg)
1120 {
1121         struct mdev_state *mdev_state =
1122                 container_of(vdev, struct mdev_state, vdev);
1123         int ret = 0;
1124         unsigned long minsz;
1125
1126         switch (cmd) {
1127         case VFIO_DEVICE_GET_INFO:
1128         {
1129                 struct vfio_device_info info;
1130
1131                 minsz = offsetofend(struct vfio_device_info, num_irqs);
1132
1133                 if (copy_from_user(&info, (void __user *)arg, minsz))
1134                         return -EFAULT;
1135
1136                 if (info.argsz < minsz)
1137                         return -EINVAL;
1138
1139                 ret = mtty_get_device_info(&info);
1140                 if (ret)
1141                         return ret;
1142
1143                 memcpy(&mdev_state->dev_info, &info, sizeof(info));
1144
1145                 if (copy_to_user((void __user *)arg, &info, minsz))
1146                         return -EFAULT;
1147
1148                 return 0;
1149         }
1150         case VFIO_DEVICE_GET_REGION_INFO:
1151         {
1152                 struct vfio_region_info info;
1153                 u16 cap_type_id = 0;
1154                 void *cap_type = NULL;
1155
1156                 minsz = offsetofend(struct vfio_region_info, offset);
1157
1158                 if (copy_from_user(&info, (void __user *)arg, minsz))
1159                         return -EFAULT;
1160
1161                 if (info.argsz < minsz)
1162                         return -EINVAL;
1163
1164                 ret = mtty_get_region_info(mdev_state, &info, &cap_type_id,
1165                                            &cap_type);
1166                 if (ret)
1167                         return ret;
1168
1169                 if (copy_to_user((void __user *)arg, &info, minsz))
1170                         return -EFAULT;
1171
1172                 return 0;
1173         }
1174
1175         case VFIO_DEVICE_GET_IRQ_INFO:
1176         {
1177                 struct vfio_irq_info info;
1178
1179                 minsz = offsetofend(struct vfio_irq_info, count);
1180
1181                 if (copy_from_user(&info, (void __user *)arg, minsz))
1182                         return -EFAULT;
1183
1184                 if ((info.argsz < minsz) ||
1185                     (info.index >= mdev_state->dev_info.num_irqs))
1186                         return -EINVAL;
1187
1188                 ret = mtty_get_irq_info(&info);
1189                 if (ret)
1190                         return ret;
1191
1192                 if (copy_to_user((void __user *)arg, &info, minsz))
1193                         return -EFAULT;
1194
1195                 return 0;
1196         }
1197         case VFIO_DEVICE_SET_IRQS:
1198         {
1199                 struct vfio_irq_set hdr;
1200                 u8 *data = NULL, *ptr = NULL;
1201                 size_t data_size = 0;
1202
1203                 minsz = offsetofend(struct vfio_irq_set, count);
1204
1205                 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1206                         return -EFAULT;
1207
1208                 ret = vfio_set_irqs_validate_and_prepare(&hdr,
1209                                                 mdev_state->dev_info.num_irqs,
1210                                                 VFIO_PCI_NUM_IRQS,
1211                                                 &data_size);
1212                 if (ret)
1213                         return ret;
1214
1215                 if (data_size) {
1216                         ptr = data = memdup_user((void __user *)(arg + minsz),
1217                                                  data_size);
1218                         if (IS_ERR(data))
1219                                 return PTR_ERR(data);
1220                 }
1221
1222                 ret = mtty_set_irqs(mdev_state, hdr.flags, hdr.index, hdr.start,
1223                                     hdr.count, data);
1224
1225                 kfree(ptr);
1226                 return ret;
1227         }
1228         case VFIO_DEVICE_RESET:
1229                 return mtty_reset(mdev_state);
1230         }
1231         return -ENOTTY;
1232 }
1233
1234 static ssize_t
1235 sample_mdev_dev_show(struct device *dev, struct device_attribute *attr,
1236                      char *buf)
1237 {
1238         return sprintf(buf, "This is MDEV %s\n", dev_name(dev));
1239 }
1240
1241 static DEVICE_ATTR_RO(sample_mdev_dev);
1242
1243 static struct attribute *mdev_dev_attrs[] = {
1244         &dev_attr_sample_mdev_dev.attr,
1245         NULL,
1246 };
1247
1248 static const struct attribute_group mdev_dev_group = {
1249         .name  = "vendor",
1250         .attrs = mdev_dev_attrs,
1251 };
1252
1253 static const struct attribute_group *mdev_dev_groups[] = {
1254         &mdev_dev_group,
1255         NULL,
1256 };
1257
1258 static unsigned int mtty_get_available(struct mdev_type *mtype)
1259 {
1260         struct mtty_type *type = container_of(mtype, struct mtty_type, type);
1261
1262         return atomic_read(&mdev_avail_ports) / type->nr_ports;
1263 }
1264
1265 static const struct vfio_device_ops mtty_dev_ops = {
1266         .name = "vfio-mtty",
1267         .init = mtty_init_dev,
1268         .release = mtty_release_dev,
1269         .read = mtty_read,
1270         .write = mtty_write,
1271         .ioctl = mtty_ioctl,
1272         .bind_iommufd   = vfio_iommufd_emulated_bind,
1273         .unbind_iommufd = vfio_iommufd_emulated_unbind,
1274         .attach_ioas    = vfio_iommufd_emulated_attach_ioas,
1275         .detach_ioas    = vfio_iommufd_emulated_detach_ioas,
1276 };
1277
1278 static struct mdev_driver mtty_driver = {
1279         .device_api = VFIO_DEVICE_API_PCI_STRING,
1280         .driver = {
1281                 .name = "mtty",
1282                 .owner = THIS_MODULE,
1283                 .mod_name = KBUILD_MODNAME,
1284                 .dev_groups = mdev_dev_groups,
1285         },
1286         .probe = mtty_probe,
1287         .remove = mtty_remove,
1288         .get_available = mtty_get_available,
1289 };
1290
1291 static void mtty_device_release(struct device *dev)
1292 {
1293         dev_dbg(dev, "mtty: released\n");
1294 }
1295
1296 static int __init mtty_dev_init(void)
1297 {
1298         int ret = 0;
1299
1300         pr_info("mtty_dev: %s\n", __func__);
1301
1302         memset(&mtty_dev, 0, sizeof(mtty_dev));
1303
1304         idr_init(&mtty_dev.vd_idr);
1305
1306         ret = alloc_chrdev_region(&mtty_dev.vd_devt, 0, MINORMASK + 1,
1307                                   MTTY_NAME);
1308
1309         if (ret < 0) {
1310                 pr_err("Error: failed to register mtty_dev, err:%d\n", ret);
1311                 return ret;
1312         }
1313
1314         cdev_init(&mtty_dev.vd_cdev, &vd_fops);
1315         cdev_add(&mtty_dev.vd_cdev, mtty_dev.vd_devt, MINORMASK + 1);
1316
1317         pr_info("major_number:%d\n", MAJOR(mtty_dev.vd_devt));
1318
1319         ret = mdev_register_driver(&mtty_driver);
1320         if (ret)
1321                 goto err_cdev;
1322
1323         mtty_dev.vd_class = class_create(MTTY_CLASS_NAME);
1324
1325         if (IS_ERR(mtty_dev.vd_class)) {
1326                 pr_err("Error: failed to register mtty_dev class\n");
1327                 ret = PTR_ERR(mtty_dev.vd_class);
1328                 goto err_driver;
1329         }
1330
1331         mtty_dev.dev.class = mtty_dev.vd_class;
1332         mtty_dev.dev.release = mtty_device_release;
1333         dev_set_name(&mtty_dev.dev, "%s", MTTY_NAME);
1334
1335         ret = device_register(&mtty_dev.dev);
1336         if (ret)
1337                 goto err_put;
1338
1339         ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
1340                                    &mtty_driver, mtty_mdev_types,
1341                                    ARRAY_SIZE(mtty_mdev_types));
1342         if (ret)
1343                 goto err_device;
1344         return 0;
1345
1346 err_device:
1347         device_del(&mtty_dev.dev);
1348 err_put:
1349         put_device(&mtty_dev.dev);
1350         class_destroy(mtty_dev.vd_class);
1351 err_driver:
1352         mdev_unregister_driver(&mtty_driver);
1353 err_cdev:
1354         cdev_del(&mtty_dev.vd_cdev);
1355         unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK + 1);
1356         return ret;
1357 }
1358
1359 static void __exit mtty_dev_exit(void)
1360 {
1361         mtty_dev.dev.bus = NULL;
1362         mdev_unregister_parent(&mtty_dev.parent);
1363
1364         device_unregister(&mtty_dev.dev);
1365         idr_destroy(&mtty_dev.vd_idr);
1366         mdev_unregister_driver(&mtty_driver);
1367         cdev_del(&mtty_dev.vd_cdev);
1368         unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK + 1);
1369         class_destroy(mtty_dev.vd_class);
1370         mtty_dev.vd_class = NULL;
1371         pr_info("mtty_dev: Unloaded!\n");
1372 }
1373
1374 module_init(mtty_dev_init)
1375 module_exit(mtty_dev_exit)
1376
1377 MODULE_LICENSE("GPL v2");
1378 MODULE_INFO(supported, "Test driver that simulate serial port over PCI");
1379 MODULE_VERSION(VERSION_STRING);
1380 MODULE_AUTHOR(DRIVER_AUTHOR);