linux/samples/vfio-mdev/mtty.c
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   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/device.h>
  16#include <linux/kernel.h>
  17#include <linux/fs.h>
  18#include <linux/poll.h>
  19#include <linux/slab.h>
  20#include <linux/cdev.h>
  21#include <linux/sched.h>
  22#include <linux/wait.h>
  23#include <linux/uuid.h>
  24#include <linux/vfio.h>
  25#include <linux/iommu.h>
  26#include <linux/sysfs.h>
  27#include <linux/ctype.h>
  28#include <linux/file.h>
  29#include <linux/mdev.h>
  30#include <linux/pci.h>
  31#include <linux/serial.h>
  32#include <uapi/linux/serial_reg.h>
  33#include <linux/eventfd.h>
  34/*
  35 * #defines
  36 */
  37
  38#define VERSION_STRING  "0.1"
  39#define DRIVER_AUTHOR   "NVIDIA Corporation"
  40
  41#define MTTY_CLASS_NAME "mtty"
  42
  43#define MTTY_NAME       "mtty"
  44
  45#define MTTY_STRING_LEN         16
  46
  47#define MTTY_CONFIG_SPACE_SIZE  0xff
  48#define MTTY_IO_BAR_SIZE        0x8
  49#define MTTY_MMIO_BAR_SIZE      0x100000
  50
  51#define STORE_LE16(addr, val)   (*(u16 *)addr = val)
  52#define STORE_LE32(addr, val)   (*(u32 *)addr = val)
  53
  54#define MAX_FIFO_SIZE   16
  55
  56#define CIRCULAR_BUF_INC_IDX(idx)    (idx = (idx + 1) & (MAX_FIFO_SIZE - 1))
  57
  58#define MTTY_VFIO_PCI_OFFSET_SHIFT   40
  59
  60#define MTTY_VFIO_PCI_OFFSET_TO_INDEX(off)   (off >> MTTY_VFIO_PCI_OFFSET_SHIFT)
  61#define MTTY_VFIO_PCI_INDEX_TO_OFFSET(index) \
  62                                ((u64)(index) << MTTY_VFIO_PCI_OFFSET_SHIFT)
  63#define MTTY_VFIO_PCI_OFFSET_MASK    \
  64                                (((u64)(1) << MTTY_VFIO_PCI_OFFSET_SHIFT) - 1)
  65#define MAX_MTTYS       24
  66
  67/*
  68 * Global Structures
  69 */
  70
  71static struct mtty_dev {
  72        dev_t           vd_devt;
  73        struct class    *vd_class;
  74        struct cdev     vd_cdev;
  75        struct idr      vd_idr;
  76        struct device   dev;
  77} mtty_dev;
  78
  79struct mdev_region_info {
  80        u64 start;
  81        u64 phys_start;
  82        u32 size;
  83        u64 vfio_offset;
  84};
  85
  86#if defined(DEBUG_REGS)
  87static const char *wr_reg[] = {
  88        "TX",
  89        "IER",
  90        "FCR",
  91        "LCR",
  92        "MCR",
  93        "LSR",
  94        "MSR",
  95        "SCR"
  96};
  97
  98static const char *rd_reg[] = {
  99        "RX",
 100        "IER",
 101        "IIR",
 102        "LCR",
 103        "MCR",
 104        "LSR",
 105        "MSR",
 106        "SCR"
 107};
 108#endif
 109
 110/* loop back buffer */
 111struct rxtx {
 112        u8 fifo[MAX_FIFO_SIZE];
 113        u8 head, tail;
 114        u8 count;
 115};
 116
 117struct serial_port {
 118        u8 uart_reg[8];         /* 8 registers */
 119        struct rxtx rxtx;       /* loop back buffer */
 120        bool dlab;
 121        bool overrun;
 122        u16 divisor;
 123        u8 fcr;                 /* FIFO control register */
 124        u8 max_fifo_size;
 125        u8 intr_trigger_level;  /* interrupt trigger level */
 126};
 127
 128/* State of each mdev device */
 129struct mdev_state {
 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
 146static struct mutex mdev_list_lock;
 147static struct list_head mdev_devices_list;
 148
 149static const struct file_operations vd_fops = {
 150        .owner          = THIS_MODULE,
 151};
 152
 153/* function prototypes */
 154
 155static int mtty_trigger_interrupt(struct mdev_state *mdev_state);
 156
 157/* Helper functions */
 158
 159static void dump_buffer(u8 *buf, uint32_t count)
 160{
 161#if defined(DEBUG)
 162        int i;
 163
 164        pr_info("Buffer:\n");
 165        for (i = 0; i < count; i++) {
 166                pr_info("%2x ", *(buf + i));
 167                if ((i + 1) % 16 == 0)
 168                        pr_info("\n");
 169        }
 170#endif
 171}
 172
 173static void mtty_create_config_space(struct mdev_state *mdev_state)
 174{
 175        /* PCI dev ID */
 176        STORE_LE32((u32 *) &mdev_state->vconfig[0x0], 0x32534348);
 177
 178        /* Control: I/O+, Mem-, BusMaster- */
 179        STORE_LE16((u16 *) &mdev_state->vconfig[0x4], 0x0001);
 180
 181        /* Status: capabilities list absent */
 182        STORE_LE16((u16 *) &mdev_state->vconfig[0x6], 0x0200);
 183
 184        /* Rev ID */
 185        mdev_state->vconfig[0x8] =  0x10;
 186
 187        /* programming interface class : 16550-compatible serial controller */
 188        mdev_state->vconfig[0x9] =  0x02;
 189
 190        /* Sub class : 00 */
 191        mdev_state->vconfig[0xa] =  0x00;
 192
 193        /* Base class : Simple Communication controllers */
 194        mdev_state->vconfig[0xb] =  0x07;
 195
 196        /* base address registers */
 197        /* BAR0: IO space */
 198        STORE_LE32((u32 *) &mdev_state->vconfig[0x10], 0x000001);
 199        mdev_state->bar_mask[0] = ~(MTTY_IO_BAR_SIZE) + 1;
 200
 201        if (mdev_state->nr_ports == 2) {
 202                /* BAR1: IO space */
 203                STORE_LE32((u32 *) &mdev_state->vconfig[0x14], 0x000001);
 204                mdev_state->bar_mask[1] = ~(MTTY_IO_BAR_SIZE) + 1;
 205        }
 206
 207        /* Subsystem ID */
 208        STORE_LE32((u32 *) &mdev_state->vconfig[0x2c], 0x32534348);
 209
 210        mdev_state->vconfig[0x34] =  0x00;   /* Cap Ptr */
 211        mdev_state->vconfig[0x3d] =  0x01;   /* interrupt pin (INTA#) */
 212
 213        /* Vendor specific data */
 214        mdev_state->vconfig[0x40] =  0x23;
 215        mdev_state->vconfig[0x43] =  0x80;
 216        mdev_state->vconfig[0x44] =  0x23;
 217        mdev_state->vconfig[0x48] =  0x23;
 218        mdev_state->vconfig[0x4c] =  0x23;
 219
 220        mdev_state->vconfig[0x60] =  0x50;
 221        mdev_state->vconfig[0x61] =  0x43;
 222        mdev_state->vconfig[0x62] =  0x49;
 223        mdev_state->vconfig[0x63] =  0x20;
 224        mdev_state->vconfig[0x64] =  0x53;
 225        mdev_state->vconfig[0x65] =  0x65;
 226        mdev_state->vconfig[0x66] =  0x72;
 227        mdev_state->vconfig[0x67] =  0x69;
 228        mdev_state->vconfig[0x68] =  0x61;
 229        mdev_state->vconfig[0x69] =  0x6c;
 230        mdev_state->vconfig[0x6a] =  0x2f;
 231        mdev_state->vconfig[0x6b] =  0x55;
 232        mdev_state->vconfig[0x6c] =  0x41;
 233        mdev_state->vconfig[0x6d] =  0x52;
 234        mdev_state->vconfig[0x6e] =  0x54;
 235}
 236
 237static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
 238                                 u8 *buf, u32 count)
 239{
 240        u32 cfg_addr, bar_mask, bar_index = 0;
 241
 242        switch (offset) {
 243        case 0x04: /* device control */
 244        case 0x06: /* device status */
 245                /* do nothing */
 246                break;
 247        case 0x3c:  /* interrupt line */
 248                mdev_state->vconfig[0x3c] = buf[0];
 249                break;
 250        case 0x3d:
 251                /*
 252                 * Interrupt Pin is hardwired to INTA.
 253                 * This field is write protected by hardware
 254                 */
 255                break;
 256        case 0x10:  /* BAR0 */
 257        case 0x14:  /* BAR1 */
 258                if (offset == 0x10)
 259                        bar_index = 0;
 260                else if (offset == 0x14)
 261                        bar_index = 1;
 262
 263                if ((mdev_state->nr_ports == 1) && (bar_index == 1)) {
 264                        STORE_LE32(&mdev_state->vconfig[offset], 0);
 265                        break;
 266                }
 267
 268                cfg_addr = *(u32 *)buf;
 269                pr_info("BAR%d addr 0x%x\n", bar_index, cfg_addr);
 270
 271                if (cfg_addr == 0xffffffff) {
 272                        bar_mask = mdev_state->bar_mask[bar_index];
 273                        cfg_addr = (cfg_addr & bar_mask);
 274                }
 275
 276                cfg_addr |= (mdev_state->vconfig[offset] & 0x3ul);
 277                STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
 278                break;
 279        case 0x18:  /* BAR2 */
 280        case 0x1c:  /* BAR3 */
 281        case 0x20:  /* BAR4 */
 282                STORE_LE32(&mdev_state->vconfig[offset], 0);
 283                break;
 284        default:
 285                pr_info("PCI config write @0x%x of %d bytes not handled\n",
 286                        offset, count);
 287                break;
 288        }
 289}
 290
 291static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
 292                                u16 offset, u8 *buf, u32 count)
 293{
 294        u8 data = *buf;
 295
 296        /* Handle data written by guest */
 297        switch (offset) {
 298        case UART_TX:
 299                /* if DLAB set, data is LSB of divisor */
 300                if (mdev_state->s[index].dlab) {
 301                        mdev_state->s[index].divisor |= data;
 302                        break;
 303                }
 304
 305                mutex_lock(&mdev_state->rxtx_lock);
 306
 307                /* save in TX buffer */
 308                if (mdev_state->s[index].rxtx.count <
 309                                mdev_state->s[index].max_fifo_size) {
 310                        mdev_state->s[index].rxtx.fifo[
 311                                        mdev_state->s[index].rxtx.head] = data;
 312                        mdev_state->s[index].rxtx.count++;
 313                        CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.head);
 314                        mdev_state->s[index].overrun = false;
 315
 316                        /*
 317                         * Trigger interrupt if receive data interrupt is
 318                         * enabled and fifo reached trigger level
 319                         */
 320                        if ((mdev_state->s[index].uart_reg[UART_IER] &
 321                                                UART_IER_RDI) &&
 322                           (mdev_state->s[index].rxtx.count ==
 323                                    mdev_state->s[index].intr_trigger_level)) {
 324                                /* trigger interrupt */
 325#if defined(DEBUG_INTR)
 326                                pr_err("Serial port %d: Fifo level trigger\n",
 327                                        index);
 328#endif
 329                                mtty_trigger_interrupt(mdev_state);
 330                        }
 331                } else {
 332#if defined(DEBUG_INTR)
 333                        pr_err("Serial port %d: Buffer Overflow\n", index);
 334#endif
 335                        mdev_state->s[index].overrun = true;
 336
 337                        /*
 338                         * Trigger interrupt if receiver line status interrupt
 339                         * is enabled
 340                         */
 341                        if (mdev_state->s[index].uart_reg[UART_IER] &
 342                                                                UART_IER_RLSI)
 343                                mtty_trigger_interrupt(mdev_state);
 344                }
 345                mutex_unlock(&mdev_state->rxtx_lock);
 346                break;
 347
 348        case UART_IER:
 349                /* if DLAB set, data is MSB of divisor */
 350                if (mdev_state->s[index].dlab)
 351                        mdev_state->s[index].divisor |= (u16)data << 8;
 352                else {
 353                        mdev_state->s[index].uart_reg[offset] = data;
 354                        mutex_lock(&mdev_state->rxtx_lock);
 355                        if ((data & UART_IER_THRI) &&
 356                            (mdev_state->s[index].rxtx.head ==
 357                                        mdev_state->s[index].rxtx.tail)) {
 358#if defined(DEBUG_INTR)
 359                                pr_err("Serial port %d: IER_THRI write\n",
 360                                        index);
 361#endif
 362                                mtty_trigger_interrupt(mdev_state);
 363                        }
 364
 365                        mutex_unlock(&mdev_state->rxtx_lock);
 366                }
 367
 368                break;
 369
 370        case UART_FCR:
 371                mdev_state->s[index].fcr = data;
 372
 373                mutex_lock(&mdev_state->rxtx_lock);
 374                if (data & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT)) {
 375                        /* clear loop back FIFO */
 376                        mdev_state->s[index].rxtx.count = 0;
 377                        mdev_state->s[index].rxtx.head = 0;
 378                        mdev_state->s[index].rxtx.tail = 0;
 379                }
 380                mutex_unlock(&mdev_state->rxtx_lock);
 381
 382                switch (data & UART_FCR_TRIGGER_MASK) {
 383                case UART_FCR_TRIGGER_1:
 384                        mdev_state->s[index].intr_trigger_level = 1;
 385                        break;
 386
 387                case UART_FCR_TRIGGER_4:
 388                        mdev_state->s[index].intr_trigger_level = 4;
 389                        break;
 390
 391                case UART_FCR_TRIGGER_8:
 392                        mdev_state->s[index].intr_trigger_level = 8;
 393                        break;
 394
 395                case UART_FCR_TRIGGER_14:
 396                        mdev_state->s[index].intr_trigger_level = 14;
 397                        break;
 398                }
 399
 400                /*
 401                 * Set trigger level to 1 otherwise or  implement timer with
 402                 * timeout of 4 characters and on expiring that timer set
 403                 * Recevice data timeout in IIR register
 404                 */
 405                mdev_state->s[index].intr_trigger_level = 1;
 406                if (data & UART_FCR_ENABLE_FIFO)
 407                        mdev_state->s[index].max_fifo_size = MAX_FIFO_SIZE;
 408                else {
 409                        mdev_state->s[index].max_fifo_size = 1;
 410                        mdev_state->s[index].intr_trigger_level = 1;
 411                }
 412
 413                break;
 414
 415        case UART_LCR:
 416                if (data & UART_LCR_DLAB) {
 417                        mdev_state->s[index].dlab = true;
 418                        mdev_state->s[index].divisor = 0;
 419                } else
 420                        mdev_state->s[index].dlab = false;
 421
 422                mdev_state->s[index].uart_reg[offset] = data;
 423                break;
 424
 425        case UART_MCR:
 426                mdev_state->s[index].uart_reg[offset] = data;
 427
 428                if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
 429                                (data & UART_MCR_OUT2)) {
 430#if defined(DEBUG_INTR)
 431                        pr_err("Serial port %d: MCR_OUT2 write\n", index);
 432#endif
 433                        mtty_trigger_interrupt(mdev_state);
 434                }
 435
 436                if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
 437                                (data & (UART_MCR_RTS | UART_MCR_DTR))) {
 438#if defined(DEBUG_INTR)
 439                        pr_err("Serial port %d: MCR RTS/DTR write\n", index);
 440#endif
 441                        mtty_trigger_interrupt(mdev_state);
 442                }
 443                break;
 444
 445        case UART_LSR:
 446        case UART_MSR:
 447                /* do nothing */
 448                break;
 449
 450        case UART_SCR:
 451                mdev_state->s[index].uart_reg[offset] = data;
 452                break;
 453
 454        default:
 455                break;
 456        }
 457}
 458
 459static void handle_bar_read(unsigned int index, struct mdev_state *mdev_state,
 460                            u16 offset, u8 *buf, u32 count)
 461{
 462        /* Handle read requests by guest */
 463        switch (offset) {
 464        case UART_RX:
 465                /* if DLAB set, data is LSB of divisor */
 466                if (mdev_state->s[index].dlab) {
 467                        *buf  = (u8)mdev_state->s[index].divisor;
 468                        break;
 469                }
 470
 471                mutex_lock(&mdev_state->rxtx_lock);
 472                /* return data in tx buffer */
 473                if (mdev_state->s[index].rxtx.head !=
 474                                 mdev_state->s[index].rxtx.tail) {
 475                        *buf = mdev_state->s[index].rxtx.fifo[
 476                                                mdev_state->s[index].rxtx.tail];
 477                        mdev_state->s[index].rxtx.count--;
 478                        CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.tail);
 479                }
 480
 481                if (mdev_state->s[index].rxtx.head ==
 482                                mdev_state->s[index].rxtx.tail) {
 483                /*
 484                 *  Trigger interrupt if tx buffer empty interrupt is
 485                 *  enabled and fifo is empty
 486                 */
 487#if defined(DEBUG_INTR)
 488                        pr_err("Serial port %d: Buffer Empty\n", index);
 489#endif
 490                        if (mdev_state->s[index].uart_reg[UART_IER] &
 491                                                         UART_IER_THRI)
 492                                mtty_trigger_interrupt(mdev_state);
 493                }
 494                mutex_unlock(&mdev_state->rxtx_lock);
 495
 496                break;
 497
 498        case UART_IER:
 499                if (mdev_state->s[index].dlab) {
 500                        *buf = (u8)(mdev_state->s[index].divisor >> 8);
 501                        break;
 502                }
 503                *buf = mdev_state->s[index].uart_reg[offset] & 0x0f;
 504                break;
 505
 506        case UART_IIR:
 507        {
 508                u8 ier = mdev_state->s[index].uart_reg[UART_IER];
 509                *buf = 0;
 510
 511                mutex_lock(&mdev_state->rxtx_lock);
 512                /* Interrupt priority 1: Parity, overrun, framing or break */
 513                if ((ier & UART_IER_RLSI) && mdev_state->s[index].overrun)
 514                        *buf |= UART_IIR_RLSI;
 515
 516                /* Interrupt priority 2: Fifo trigger level reached */
 517                if ((ier & UART_IER_RDI) &&
 518                    (mdev_state->s[index].rxtx.count >=
 519                      mdev_state->s[index].intr_trigger_level))
 520                        *buf |= UART_IIR_RDI;
 521
 522                /* Interrupt priotiry 3: transmitter holding register empty */
 523                if ((ier & UART_IER_THRI) &&
 524                    (mdev_state->s[index].rxtx.head ==
 525                                mdev_state->s[index].rxtx.tail))
 526                        *buf |= UART_IIR_THRI;
 527
 528                /* Interrupt priotiry 4: Modem status: CTS, DSR, RI or DCD  */
 529                if ((ier & UART_IER_MSI) &&
 530                    (mdev_state->s[index].uart_reg[UART_MCR] &
 531                                 (UART_MCR_RTS | UART_MCR_DTR)))
 532                        *buf |= UART_IIR_MSI;
 533
 534                /* bit0: 0=> interrupt pending, 1=> no interrupt is pending */
 535                if (*buf == 0)
 536                        *buf = UART_IIR_NO_INT;
 537
 538                /* set bit 6 & 7 to be 16550 compatible */
 539                *buf |= 0xC0;
 540                mutex_unlock(&mdev_state->rxtx_lock);
 541        }
 542        break;
 543
 544        case UART_LCR:
 545        case UART_MCR:
 546                *buf = mdev_state->s[index].uart_reg[offset];
 547                break;
 548
 549        case UART_LSR:
 550        {
 551                u8 lsr = 0;
 552
 553                mutex_lock(&mdev_state->rxtx_lock);
 554                /* atleast one char in FIFO */
 555                if (mdev_state->s[index].rxtx.head !=
 556                                 mdev_state->s[index].rxtx.tail)
 557                        lsr |= UART_LSR_DR;
 558
 559                /* if FIFO overrun */
 560                if (mdev_state->s[index].overrun)
 561                        lsr |= UART_LSR_OE;
 562
 563                /* transmit FIFO empty and tramsitter empty */
 564                if (mdev_state->s[index].rxtx.head ==
 565                                 mdev_state->s[index].rxtx.tail)
 566                        lsr |= UART_LSR_TEMT | UART_LSR_THRE;
 567
 568                mutex_unlock(&mdev_state->rxtx_lock);
 569                *buf = lsr;
 570                break;
 571        }
 572        case UART_MSR:
 573                *buf = UART_MSR_DSR | UART_MSR_DDSR | UART_MSR_DCD;
 574
 575                mutex_lock(&mdev_state->rxtx_lock);
 576                /* if AFE is 1 and FIFO have space, set CTS bit */
 577                if (mdev_state->s[index].uart_reg[UART_MCR] &
 578                                                 UART_MCR_AFE) {
 579                        if (mdev_state->s[index].rxtx.count <
 580                                        mdev_state->s[index].max_fifo_size)
 581                                *buf |= UART_MSR_CTS | UART_MSR_DCTS;
 582                } else
 583                        *buf |= UART_MSR_CTS | UART_MSR_DCTS;
 584                mutex_unlock(&mdev_state->rxtx_lock);
 585
 586                break;
 587
 588        case UART_SCR:
 589                *buf = mdev_state->s[index].uart_reg[offset];
 590                break;
 591
 592        default:
 593                break;
 594        }
 595}
 596
 597static void mdev_read_base(struct mdev_state *mdev_state)
 598{
 599        int index, pos;
 600        u32 start_lo, start_hi;
 601        u32 mem_type;
 602
 603        pos = PCI_BASE_ADDRESS_0;
 604
 605        for (index = 0; index <= VFIO_PCI_BAR5_REGION_INDEX; index++) {
 606
 607                if (!mdev_state->region_info[index].size)
 608                        continue;
 609
 610                start_lo = (*(u32 *)(mdev_state->vconfig + pos)) &
 611                        PCI_BASE_ADDRESS_MEM_MASK;
 612                mem_type = (*(u32 *)(mdev_state->vconfig + pos)) &
 613                        PCI_BASE_ADDRESS_MEM_TYPE_MASK;
 614
 615                switch (mem_type) {
 616                case PCI_BASE_ADDRESS_MEM_TYPE_64:
 617                        start_hi = (*(u32 *)(mdev_state->vconfig + pos + 4));
 618                        pos += 4;
 619                        break;
 620                case PCI_BASE_ADDRESS_MEM_TYPE_32:
 621                case PCI_BASE_ADDRESS_MEM_TYPE_1M:
 622                        /* 1M mem BAR treated as 32-bit BAR */
 623                default:
 624                        /* mem unknown type treated as 32-bit BAR */
 625                        start_hi = 0;
 626                        break;
 627                }
 628                pos += 4;
 629                mdev_state->region_info[index].start = ((u64)start_hi << 32) |
 630                                                        start_lo;
 631        }
 632}
 633
 634static ssize_t mdev_access(struct mdev_device *mdev, u8 *buf, size_t count,
 635                           loff_t pos, bool is_write)
 636{
 637        struct mdev_state *mdev_state;
 638        unsigned int index;
 639        loff_t offset;
 640        int ret = 0;
 641
 642        if (!mdev || !buf)
 643                return -EINVAL;
 644
 645        mdev_state = mdev_get_drvdata(mdev);
 646        if (!mdev_state) {
 647                pr_err("%s mdev_state not found\n", __func__);
 648                return -EINVAL;
 649        }
 650
 651        mutex_lock(&mdev_state->ops_lock);
 652
 653        index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(pos);
 654        offset = pos & MTTY_VFIO_PCI_OFFSET_MASK;
 655        switch (index) {
 656        case VFIO_PCI_CONFIG_REGION_INDEX:
 657
 658#if defined(DEBUG)
 659                pr_info("%s: PCI config space %s at offset 0x%llx\n",
 660                         __func__, is_write ? "write" : "read", offset);
 661#endif
 662                if (is_write) {
 663                        dump_buffer(buf, count);
 664                        handle_pci_cfg_write(mdev_state, offset, buf, count);
 665                } else {
 666                        memcpy(buf, (mdev_state->vconfig + offset), count);
 667                        dump_buffer(buf, count);
 668                }
 669
 670                break;
 671
 672        case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
 673                if (!mdev_state->region_info[index].start)
 674                        mdev_read_base(mdev_state);
 675
 676                if (is_write) {
 677                        dump_buffer(buf, count);
 678
 679#if defined(DEBUG_REGS)
 680                        pr_info("%s: BAR%d  WR @0x%llx %s val:0x%02x dlab:%d\n",
 681                                __func__, index, offset, wr_reg[offset],
 682                                *buf, mdev_state->s[index].dlab);
 683#endif
 684                        handle_bar_write(index, mdev_state, offset, buf, count);
 685                } else {
 686                        handle_bar_read(index, mdev_state, offset, buf, count);
 687                        dump_buffer(buf, count);
 688
 689#if defined(DEBUG_REGS)
 690                        pr_info("%s: BAR%d  RD @0x%llx %s val:0x%02x dlab:%d\n",
 691                                __func__, index, offset, rd_reg[offset],
 692                                *buf, mdev_state->s[index].dlab);
 693#endif
 694                }
 695                break;
 696
 697        default:
 698                ret = -1;
 699                goto accessfailed;
 700        }
 701
 702        ret = count;
 703
 704
 705accessfailed:
 706        mutex_unlock(&mdev_state->ops_lock);
 707
 708        return ret;
 709}
 710
 711static int mtty_create(struct kobject *kobj, struct mdev_device *mdev)
 712{
 713        struct mdev_state *mdev_state;
 714        char name[MTTY_STRING_LEN];
 715        int nr_ports = 0, i;
 716
 717        if (!mdev)
 718                return -EINVAL;
 719
 720        for (i = 0; i < 2; i++) {
 721                snprintf(name, MTTY_STRING_LEN, "%s-%d",
 722                        dev_driver_string(mdev_parent_dev(mdev)), i + 1);
 723                if (!strcmp(kobj->name, name)) {
 724                        nr_ports = i + 1;
 725                        break;
 726                }
 727        }
 728
 729        if (!nr_ports)
 730                return -EINVAL;
 731
 732        mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
 733        if (mdev_state == NULL)
 734                return -ENOMEM;
 735
 736        mdev_state->nr_ports = nr_ports;
 737        mdev_state->irq_index = -1;
 738        mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
 739        mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
 740        mutex_init(&mdev_state->rxtx_lock);
 741        mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
 742
 743        if (mdev_state->vconfig == NULL) {
 744                kfree(mdev_state);
 745                return -ENOMEM;
 746        }
 747
 748        mutex_init(&mdev_state->ops_lock);
 749        mdev_state->mdev = mdev;
 750        mdev_set_drvdata(mdev, mdev_state);
 751
 752        mtty_create_config_space(mdev_state);
 753
 754        mutex_lock(&mdev_list_lock);
 755        list_add(&mdev_state->next, &mdev_devices_list);
 756        mutex_unlock(&mdev_list_lock);
 757
 758        return 0;
 759}
 760
 761static int mtty_remove(struct mdev_device *mdev)
 762{
 763        struct mdev_state *mds, *tmp_mds;
 764        struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
 765        int ret = -EINVAL;
 766
 767        mutex_lock(&mdev_list_lock);
 768        list_for_each_entry_safe(mds, tmp_mds, &mdev_devices_list, next) {
 769                if (mdev_state == mds) {
 770                        list_del(&mdev_state->next);
 771                        mdev_set_drvdata(mdev, NULL);
 772                        kfree(mdev_state->vconfig);
 773                        kfree(mdev_state);
 774                        ret = 0;
 775                        break;
 776                }
 777        }
 778        mutex_unlock(&mdev_list_lock);
 779
 780        return ret;
 781}
 782
 783static int mtty_reset(struct mdev_device *mdev)
 784{
 785        struct mdev_state *mdev_state;
 786
 787        if (!mdev)
 788                return -EINVAL;
 789
 790        mdev_state = mdev_get_drvdata(mdev);
 791        if (!mdev_state)
 792                return -EINVAL;
 793
 794        pr_info("%s: called\n", __func__);
 795
 796        return 0;
 797}
 798
 799static ssize_t mtty_read(struct mdev_device *mdev, char __user *buf,
 800                         size_t count, loff_t *ppos)
 801{
 802        unsigned int done = 0;
 803        int ret;
 804
 805        while (count) {
 806                size_t filled;
 807
 808                if (count >= 4 && !(*ppos % 4)) {
 809                        u32 val;
 810
 811                        ret =  mdev_access(mdev, (u8 *)&val, sizeof(val),
 812                                           *ppos, false);
 813                        if (ret <= 0)
 814                                goto read_err;
 815
 816                        if (copy_to_user(buf, &val, sizeof(val)))
 817                                goto read_err;
 818
 819                        filled = 4;
 820                } else if (count >= 2 && !(*ppos % 2)) {
 821                        u16 val;
 822
 823                        ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
 824                                          *ppos, false);
 825                        if (ret <= 0)
 826                                goto read_err;
 827
 828                        if (copy_to_user(buf, &val, sizeof(val)))
 829                                goto read_err;
 830
 831                        filled = 2;
 832                } else {
 833                        u8 val;
 834
 835                        ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
 836                                          *ppos, false);
 837                        if (ret <= 0)
 838                                goto read_err;
 839
 840                        if (copy_to_user(buf, &val, sizeof(val)))
 841                                goto read_err;
 842
 843                        filled = 1;
 844                }
 845
 846                count -= filled;
 847                done += filled;
 848                *ppos += filled;
 849                buf += filled;
 850        }
 851
 852        return done;
 853
 854read_err:
 855        return -EFAULT;
 856}
 857
 858static ssize_t mtty_write(struct mdev_device *mdev, const char __user *buf,
 859                   size_t count, loff_t *ppos)
 860{
 861        unsigned int done = 0;
 862        int ret;
 863
 864        while (count) {
 865                size_t filled;
 866
 867                if (count >= 4 && !(*ppos % 4)) {
 868                        u32 val;
 869
 870                        if (copy_from_user(&val, buf, sizeof(val)))
 871                                goto write_err;
 872
 873                        ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
 874                                          *ppos, true);
 875                        if (ret <= 0)
 876                                goto write_err;
 877
 878                        filled = 4;
 879                } else if (count >= 2 && !(*ppos % 2)) {
 880                        u16 val;
 881
 882                        if (copy_from_user(&val, buf, sizeof(val)))
 883                                goto write_err;
 884
 885                        ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
 886                                          *ppos, true);
 887                        if (ret <= 0)
 888                                goto write_err;
 889
 890                        filled = 2;
 891                } else {
 892                        u8 val;
 893
 894                        if (copy_from_user(&val, buf, sizeof(val)))
 895                                goto write_err;
 896
 897                        ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
 898                                          *ppos, true);
 899                        if (ret <= 0)
 900                                goto write_err;
 901
 902                        filled = 1;
 903                }
 904                count -= filled;
 905                done += filled;
 906                *ppos += filled;
 907                buf += filled;
 908        }
 909
 910        return done;
 911write_err:
 912        return -EFAULT;
 913}
 914
 915static int mtty_set_irqs(struct mdev_device *mdev, uint32_t flags,
 916                         unsigned int index, unsigned int start,
 917                         unsigned int count, void *data)
 918{
 919        int ret = 0;
 920        struct mdev_state *mdev_state;
 921
 922        if (!mdev)
 923                return -EINVAL;
 924
 925        mdev_state = mdev_get_drvdata(mdev);
 926        if (!mdev_state)
 927                return -EINVAL;
 928
 929        mutex_lock(&mdev_state->ops_lock);
 930        switch (index) {
 931        case VFIO_PCI_INTX_IRQ_INDEX:
 932                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 933                case VFIO_IRQ_SET_ACTION_MASK:
 934                case VFIO_IRQ_SET_ACTION_UNMASK:
 935                        break;
 936                case VFIO_IRQ_SET_ACTION_TRIGGER:
 937                {
 938                        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 939                                pr_info("%s: disable INTx\n", __func__);
 940                                if (mdev_state->intx_evtfd)
 941                                        eventfd_ctx_put(mdev_state->intx_evtfd);
 942                                break;
 943                        }
 944
 945                        if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 946                                int fd = *(int *)data;
 947
 948                                if (fd > 0) {
 949                                        struct eventfd_ctx *evt;
 950
 951                                        evt = eventfd_ctx_fdget(fd);
 952                                        if (IS_ERR(evt)) {
 953                                                ret = PTR_ERR(evt);
 954                                                break;
 955                                        }
 956                                        mdev_state->intx_evtfd = evt;
 957                                        mdev_state->irq_fd = fd;
 958                                        mdev_state->irq_index = index;
 959                                        break;
 960                                }
 961                        }
 962                        break;
 963                }
 964                }
 965                break;
 966        case VFIO_PCI_MSI_IRQ_INDEX:
 967                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 968                case VFIO_IRQ_SET_ACTION_MASK:
 969                case VFIO_IRQ_SET_ACTION_UNMASK:
 970                        break;
 971                case VFIO_IRQ_SET_ACTION_TRIGGER:
 972                        if (flags & VFIO_IRQ_SET_DATA_NONE) {
 973                                if (mdev_state->msi_evtfd)
 974                                        eventfd_ctx_put(mdev_state->msi_evtfd);
 975                                pr_info("%s: disable MSI\n", __func__);
 976                                mdev_state->irq_index = VFIO_PCI_INTX_IRQ_INDEX;
 977                                break;
 978                        }
 979                        if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 980                                int fd = *(int *)data;
 981                                struct eventfd_ctx *evt;
 982
 983                                if (fd <= 0)
 984                                        break;
 985
 986                                if (mdev_state->msi_evtfd)
 987                                        break;
 988
 989                                evt = eventfd_ctx_fdget(fd);
 990                                if (IS_ERR(evt)) {
 991                                        ret = PTR_ERR(evt);
 992                                        break;
 993                                }
 994                                mdev_state->msi_evtfd = evt;
 995                                mdev_state->irq_fd = fd;
 996                                mdev_state->irq_index = index;
 997                        }
 998                        break;
 999        }
1000        break;
1001        case VFIO_PCI_MSIX_IRQ_INDEX:
1002                pr_info("%s: MSIX_IRQ\n", __func__);
1003                break;
1004        case VFIO_PCI_ERR_IRQ_INDEX:
1005                pr_info("%s: ERR_IRQ\n", __func__);
1006                break;
1007        case VFIO_PCI_REQ_IRQ_INDEX:
1008                pr_info("%s: REQ_IRQ\n", __func__);
1009                break;
1010        }
1011
1012        mutex_unlock(&mdev_state->ops_lock);
1013        return ret;
1014}
1015
1016static int mtty_trigger_interrupt(struct mdev_state *mdev_state)
1017{
1018        int ret = -1;
1019
1020        if ((mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX) &&
1021            (!mdev_state->msi_evtfd))
1022                return -EINVAL;
1023        else if ((mdev_state->irq_index == VFIO_PCI_INTX_IRQ_INDEX) &&
1024                 (!mdev_state->intx_evtfd)) {
1025                pr_info("%s: Intr eventfd not found\n", __func__);
1026                return -EINVAL;
1027        }
1028
1029        if (mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX)
1030                ret = eventfd_signal(mdev_state->msi_evtfd, 1);
1031        else
1032                ret = eventfd_signal(mdev_state->intx_evtfd, 1);
1033
1034#if defined(DEBUG_INTR)
1035        pr_info("Intx triggered\n");
1036#endif
1037        if (ret != 1)
1038                pr_err("%s: eventfd signal failed (%d)\n", __func__, ret);
1039
1040        return ret;
1041}
1042
1043static int mtty_get_region_info(struct mdev_device *mdev,
1044                         struct vfio_region_info *region_info,
1045                         u16 *cap_type_id, void **cap_type)
1046{
1047        unsigned int size = 0;
1048        struct mdev_state *mdev_state;
1049        u32 bar_index;
1050
1051        if (!mdev)
1052                return -EINVAL;
1053
1054        mdev_state = mdev_get_drvdata(mdev);
1055        if (!mdev_state)
1056                return -EINVAL;
1057
1058        bar_index = region_info->index;
1059        if (bar_index >= VFIO_PCI_NUM_REGIONS)
1060                return -EINVAL;
1061
1062        mutex_lock(&mdev_state->ops_lock);
1063
1064        switch (bar_index) {
1065        case VFIO_PCI_CONFIG_REGION_INDEX:
1066                size = MTTY_CONFIG_SPACE_SIZE;
1067                break;
1068        case VFIO_PCI_BAR0_REGION_INDEX:
1069                size = MTTY_IO_BAR_SIZE;
1070                break;
1071        case VFIO_PCI_BAR1_REGION_INDEX:
1072                if (mdev_state->nr_ports == 2)
1073                        size = MTTY_IO_BAR_SIZE;
1074                break;
1075        default:
1076                size = 0;
1077                break;
1078        }
1079
1080        mdev_state->region_info[bar_index].size = size;
1081        mdev_state->region_info[bar_index].vfio_offset =
1082                MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
1083
1084        region_info->size = size;
1085        region_info->offset = MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
1086        region_info->flags = VFIO_REGION_INFO_FLAG_READ |
1087                VFIO_REGION_INFO_FLAG_WRITE;
1088        mutex_unlock(&mdev_state->ops_lock);
1089        return 0;
1090}
1091
1092static int mtty_get_irq_info(struct mdev_device *mdev,
1093                             struct vfio_irq_info *irq_info)
1094{
1095        switch (irq_info->index) {
1096        case VFIO_PCI_INTX_IRQ_INDEX:
1097        case VFIO_PCI_MSI_IRQ_INDEX:
1098        case VFIO_PCI_REQ_IRQ_INDEX:
1099                break;
1100
1101        default:
1102                return -EINVAL;
1103        }
1104
1105        irq_info->flags = VFIO_IRQ_INFO_EVENTFD;
1106        irq_info->count = 1;
1107
1108        if (irq_info->index == VFIO_PCI_INTX_IRQ_INDEX)
1109                irq_info->flags |= (VFIO_IRQ_INFO_MASKABLE |
1110                                VFIO_IRQ_INFO_AUTOMASKED);
1111        else
1112                irq_info->flags |= VFIO_IRQ_INFO_NORESIZE;
1113
1114        return 0;
1115}
1116
1117static int mtty_get_device_info(struct mdev_device *mdev,
1118                         struct vfio_device_info *dev_info)
1119{
1120        dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
1121        dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
1122        dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
1123
1124        return 0;
1125}
1126
1127static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
1128                        unsigned long arg)
1129{
1130        int ret = 0;
1131        unsigned long minsz;
1132        struct mdev_state *mdev_state;
1133
1134        if (!mdev)
1135                return -EINVAL;
1136
1137        mdev_state = mdev_get_drvdata(mdev);
1138        if (!mdev_state)
1139                return -ENODEV;
1140
1141        switch (cmd) {
1142        case VFIO_DEVICE_GET_INFO:
1143        {
1144                struct vfio_device_info info;
1145
1146                minsz = offsetofend(struct vfio_device_info, num_irqs);
1147
1148                if (copy_from_user(&info, (void __user *)arg, minsz))
1149                        return -EFAULT;
1150
1151                if (info.argsz < minsz)
1152                        return -EINVAL;
1153
1154                ret = mtty_get_device_info(mdev, &info);
1155                if (ret)
1156                        return ret;
1157
1158                memcpy(&mdev_state->dev_info, &info, sizeof(info));
1159
1160                if (copy_to_user((void __user *)arg, &info, minsz))
1161                        return -EFAULT;
1162
1163                return 0;
1164        }
1165        case VFIO_DEVICE_GET_REGION_INFO:
1166        {
1167                struct vfio_region_info info;
1168                u16 cap_type_id = 0;
1169                void *cap_type = NULL;
1170
1171                minsz = offsetofend(struct vfio_region_info, offset);
1172
1173                if (copy_from_user(&info, (void __user *)arg, minsz))
1174                        return -EFAULT;
1175
1176                if (info.argsz < minsz)
1177                        return -EINVAL;
1178
1179                ret = mtty_get_region_info(mdev, &info, &cap_type_id,
1180                                           &cap_type);
1181                if (ret)
1182                        return ret;
1183
1184                if (copy_to_user((void __user *)arg, &info, minsz))
1185                        return -EFAULT;
1186
1187                return 0;
1188        }
1189
1190        case VFIO_DEVICE_GET_IRQ_INFO:
1191        {
1192                struct vfio_irq_info info;
1193
1194                minsz = offsetofend(struct vfio_irq_info, count);
1195
1196                if (copy_from_user(&info, (void __user *)arg, minsz))
1197                        return -EFAULT;
1198
1199                if ((info.argsz < minsz) ||
1200                    (info.index >= mdev_state->dev_info.num_irqs))
1201                        return -EINVAL;
1202
1203                ret = mtty_get_irq_info(mdev, &info);
1204                if (ret)
1205                        return ret;
1206
1207                if (copy_to_user((void __user *)arg, &info, minsz))
1208                        return -EFAULT;
1209
1210                return 0;
1211        }
1212        case VFIO_DEVICE_SET_IRQS:
1213        {
1214                struct vfio_irq_set hdr;
1215                u8 *data = NULL, *ptr = NULL;
1216                size_t data_size = 0;
1217
1218                minsz = offsetofend(struct vfio_irq_set, count);
1219
1220                if (copy_from_user(&hdr, (void __user *)arg, minsz))
1221                        return -EFAULT;
1222
1223                ret = vfio_set_irqs_validate_and_prepare(&hdr,
1224                                                mdev_state->dev_info.num_irqs,
1225                                                VFIO_PCI_NUM_IRQS,
1226                                                &data_size);
1227                if (ret)
1228                        return ret;
1229
1230                if (data_size) {
1231                        ptr = data = memdup_user((void __user *)(arg + minsz),
1232                                                 data_size);
1233                        if (IS_ERR(data))
1234                                return PTR_ERR(data);
1235                }
1236
1237                ret = mtty_set_irqs(mdev, hdr.flags, hdr.index, hdr.start,
1238                                    hdr.count, data);
1239
1240                kfree(ptr);
1241                return ret;
1242        }
1243        case VFIO_DEVICE_RESET:
1244                return mtty_reset(mdev);
1245        }
1246        return -ENOTTY;
1247}
1248
1249static int mtty_open(struct mdev_device *mdev)
1250{
1251        pr_info("%s\n", __func__);
1252        return 0;
1253}
1254
1255static void mtty_close(struct mdev_device *mdev)
1256{
1257        pr_info("%s\n", __func__);
1258}
1259
1260static ssize_t
1261sample_mtty_dev_show(struct device *dev, struct device_attribute *attr,
1262                     char *buf)
1263{
1264        return sprintf(buf, "This is phy device\n");
1265}
1266
1267static DEVICE_ATTR_RO(sample_mtty_dev);
1268
1269static struct attribute *mtty_dev_attrs[] = {
1270        &dev_attr_sample_mtty_dev.attr,
1271        NULL,
1272};
1273
1274static const struct attribute_group mtty_dev_group = {
1275        .name  = "mtty_dev",
1276        .attrs = mtty_dev_attrs,
1277};
1278
1279static const struct attribute_group *mtty_dev_groups[] = {
1280        &mtty_dev_group,
1281        NULL,
1282};
1283
1284static ssize_t
1285sample_mdev_dev_show(struct device *dev, struct device_attribute *attr,
1286                     char *buf)
1287{
1288        if (mdev_from_dev(dev))
1289                return sprintf(buf, "This is MDEV %s\n", dev_name(dev));
1290
1291        return sprintf(buf, "\n");
1292}
1293
1294static DEVICE_ATTR_RO(sample_mdev_dev);
1295
1296static struct attribute *mdev_dev_attrs[] = {
1297        &dev_attr_sample_mdev_dev.attr,
1298        NULL,
1299};
1300
1301static const struct attribute_group mdev_dev_group = {
1302        .name  = "vendor",
1303        .attrs = mdev_dev_attrs,
1304};
1305
1306static const struct attribute_group *mdev_dev_groups[] = {
1307        &mdev_dev_group,
1308        NULL,
1309};
1310
1311static ssize_t
1312name_show(struct kobject *kobj, struct device *dev, char *buf)
1313{
1314        char name[MTTY_STRING_LEN];
1315        int i;
1316        const char *name_str[2] = {"Single port serial", "Dual port serial"};
1317
1318        for (i = 0; i < 2; i++) {
1319                snprintf(name, MTTY_STRING_LEN, "%s-%d",
1320                         dev_driver_string(dev), i + 1);
1321                if (!strcmp(kobj->name, name))
1322                        return sprintf(buf, "%s\n", name_str[i]);
1323        }
1324
1325        return -EINVAL;
1326}
1327
1328static MDEV_TYPE_ATTR_RO(name);
1329
1330static ssize_t
1331available_instances_show(struct kobject *kobj, struct device *dev, char *buf)
1332{
1333        char name[MTTY_STRING_LEN];
1334        int i;
1335        struct mdev_state *mds;
1336        int ports = 0, used = 0;
1337
1338        for (i = 0; i < 2; i++) {
1339                snprintf(name, MTTY_STRING_LEN, "%s-%d",
1340                         dev_driver_string(dev), i + 1);
1341                if (!strcmp(kobj->name, name)) {
1342                        ports = i + 1;
1343                        break;
1344                }
1345        }
1346
1347        if (!ports)
1348                return -EINVAL;
1349
1350        list_for_each_entry(mds, &mdev_devices_list, next)
1351                used += mds->nr_ports;
1352
1353        return sprintf(buf, "%d\n", (MAX_MTTYS - used)/ports);
1354}
1355
1356static MDEV_TYPE_ATTR_RO(available_instances);
1357
1358
1359static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
1360                               char *buf)
1361{
1362        return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
1363}
1364
1365static MDEV_TYPE_ATTR_RO(device_api);
1366
1367static struct attribute *mdev_types_attrs[] = {
1368        &mdev_type_attr_name.attr,
1369        &mdev_type_attr_device_api.attr,
1370        &mdev_type_attr_available_instances.attr,
1371        NULL,
1372};
1373
1374static struct attribute_group mdev_type_group1 = {
1375        .name  = "1",
1376        .attrs = mdev_types_attrs,
1377};
1378
1379static struct attribute_group mdev_type_group2 = {
1380        .name  = "2",
1381        .attrs = mdev_types_attrs,
1382};
1383
1384static struct attribute_group *mdev_type_groups[] = {
1385        &mdev_type_group1,
1386        &mdev_type_group2,
1387        NULL,
1388};
1389
1390static const struct mdev_parent_ops mdev_fops = {
1391        .owner                  = THIS_MODULE,
1392        .dev_attr_groups        = mtty_dev_groups,
1393        .mdev_attr_groups       = mdev_dev_groups,
1394        .supported_type_groups  = mdev_type_groups,
1395        .create                 = mtty_create,
1396        .remove                 = mtty_remove,
1397        .open                   = mtty_open,
1398        .release                = mtty_close,
1399        .read                   = mtty_read,
1400        .write                  = mtty_write,
1401        .ioctl                  = mtty_ioctl,
1402};
1403
1404static void mtty_device_release(struct device *dev)
1405{
1406        dev_dbg(dev, "mtty: released\n");
1407}
1408
1409static int __init mtty_dev_init(void)
1410{
1411        int ret = 0;
1412
1413        pr_info("mtty_dev: %s\n", __func__);
1414
1415        memset(&mtty_dev, 0, sizeof(mtty_dev));
1416
1417        idr_init(&mtty_dev.vd_idr);
1418
1419        ret = alloc_chrdev_region(&mtty_dev.vd_devt, 0, MINORMASK + 1,
1420                                  MTTY_NAME);
1421
1422        if (ret < 0) {
1423                pr_err("Error: failed to register mtty_dev, err:%d\n", ret);
1424                return ret;
1425        }
1426
1427        cdev_init(&mtty_dev.vd_cdev, &vd_fops);
1428        cdev_add(&mtty_dev.vd_cdev, mtty_dev.vd_devt, MINORMASK + 1);
1429
1430        pr_info("major_number:%d\n", MAJOR(mtty_dev.vd_devt));
1431
1432        mtty_dev.vd_class = class_create(THIS_MODULE, MTTY_CLASS_NAME);
1433
1434        if (IS_ERR(mtty_dev.vd_class)) {
1435                pr_err("Error: failed to register mtty_dev class\n");
1436                ret = PTR_ERR(mtty_dev.vd_class);
1437                goto failed1;
1438        }
1439
1440        mtty_dev.dev.class = mtty_dev.vd_class;
1441        mtty_dev.dev.release = mtty_device_release;
1442        dev_set_name(&mtty_dev.dev, "%s", MTTY_NAME);
1443
1444        ret = device_register(&mtty_dev.dev);
1445        if (ret)
1446                goto failed2;
1447
1448        ret = mdev_register_device(&mtty_dev.dev, &mdev_fops);
1449        if (ret)
1450                goto failed3;
1451
1452        mutex_init(&mdev_list_lock);
1453        INIT_LIST_HEAD(&mdev_devices_list);
1454
1455        goto all_done;
1456
1457failed3:
1458
1459        device_unregister(&mtty_dev.dev);
1460failed2:
1461        class_destroy(mtty_dev.vd_class);
1462
1463failed1:
1464        cdev_del(&mtty_dev.vd_cdev);
1465        unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK + 1);
1466
1467all_done:
1468        return ret;
1469}
1470
1471static void __exit mtty_dev_exit(void)
1472{
1473        mtty_dev.dev.bus = NULL;
1474        mdev_unregister_device(&mtty_dev.dev);
1475
1476        device_unregister(&mtty_dev.dev);
1477        idr_destroy(&mtty_dev.vd_idr);
1478        cdev_del(&mtty_dev.vd_cdev);
1479        unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK + 1);
1480        class_destroy(mtty_dev.vd_class);
1481        mtty_dev.vd_class = NULL;
1482        pr_info("mtty_dev: Unloaded!\n");
1483}
1484
1485module_init(mtty_dev_init)
1486module_exit(mtty_dev_exit)
1487
1488MODULE_LICENSE("GPL v2");
1489MODULE_INFO(supported, "Test driver that simulate serial port over PCI");
1490MODULE_VERSION(VERSION_STRING);
1491MODULE_AUTHOR(DRIVER_AUTHOR);
1492