drivers/w1/masters/ds2490.c

   1 /*
   2  *      ds2490.c  USB to one wire bridge
   3  *
   4  * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
   5  *
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/mod_devicetable.h>
  25 #include <linux/usb.h>
  26 #include <linux/slab.h>
  27
  28 #include <linux/w1.h>
  29
  30 /* USB Standard */
  31 /* USB Control request vendor type */
  32 #define VENDOR                          0x40
  33
  34 /* COMMAND TYPE CODES */
  35 #define CONTROL_CMD                     0x00
  36 #define COMM_CMD                        0x01
  37 #define MODE_CMD                        0x02
  38
  39 /* CONTROL COMMAND CODES */
  40 #define CTL_RESET_DEVICE                0x0000
  41 #define CTL_START_EXE                   0x0001
  42 #define CTL_RESUME_EXE                  0x0002
  43 #define CTL_HALT_EXE_IDLE               0x0003
  44 #define CTL_HALT_EXE_DONE               0x0004
  45 #define CTL_FLUSH_COMM_CMDS             0x0007
  46 #define CTL_FLUSH_RCV_BUFFER            0x0008
  47 #define CTL_FLUSH_XMT_BUFFER            0x0009
  48 #define CTL_GET_COMM_CMDS               0x000A
  49
  50 /* MODE COMMAND CODES */
  51 #define MOD_PULSE_EN                    0x0000
  52 #define MOD_SPEED_CHANGE_EN             0x0001
  53 #define MOD_1WIRE_SPEED                 0x0002
  54 #define MOD_STRONG_PU_DURATION          0x0003
  55 #define MOD_PULLDOWN_SLEWRATE           0x0004
  56 #define MOD_PROG_PULSE_DURATION         0x0005
  57 #define MOD_WRITE1_LOWTIME              0x0006
  58 #define MOD_DSOW0_TREC                  0x0007
  59
  60 /* COMMUNICATION COMMAND CODES */
  61 #define COMM_ERROR_ESCAPE               0x0601
  62 #define COMM_SET_DURATION               0x0012
  63 #define COMM_BIT_IO                     0x0020
  64 #define COMM_PULSE                      0x0030
  65 #define COMM_1_WIRE_RESET               0x0042
  66 #define COMM_BYTE_IO                    0x0052
  67 #define COMM_MATCH_ACCESS               0x0064
  68 #define COMM_BLOCK_IO                   0x0074
  69 #define COMM_READ_STRAIGHT              0x0080
  70 #define COMM_DO_RELEASE                 0x6092
  71 #define COMM_SET_PATH                   0x00A2
  72 #define COMM_WRITE_SRAM_PAGE            0x00B2
  73 #define COMM_WRITE_EPROM                0x00C4
  74 #define COMM_READ_CRC_PROT_PAGE         0x00D4
  75 #define COMM_READ_REDIRECT_PAGE_CRC     0x21E4
  76 #define COMM_SEARCH_ACCESS              0x00F4
  77
  78 /* Communication command bits */
  79 #define COMM_TYPE                       0x0008
  80 #define COMM_SE                         0x0008
  81 #define COMM_D                          0x0008
  82 #define COMM_Z                          0x0008
  83 #define COMM_CH                         0x0008
  84 #define COMM_SM                         0x0008
  85 #define COMM_R                          0x0008
  86 #define COMM_IM                         0x0001
  87
  88 #define COMM_PS                         0x4000
  89 #define COMM_PST                        0x4000
  90 #define COMM_CIB                        0x4000
  91 #define COMM_RTS                        0x4000
  92 #define COMM_DT                         0x2000
  93 #define COMM_SPU                        0x1000
  94 #define COMM_F                          0x0800
  95 #define COMM_NTF                        0x0400
  96 #define COMM_ICP                        0x0200
  97 #define COMM_RST                        0x0100
  98
  99 #define PULSE_PROG                      0x01
 100 #define PULSE_SPUE                      0x02
 101
 102 #define BRANCH_MAIN                     0xCC
 103 #define BRANCH_AUX                      0x33
 104
 105 /* Status flags */
 106 #define ST_SPUA                         0x01  /* Strong Pull-up is active */
 107 #define ST_PRGA                         0x02  /* 12V programming pulse is being generated */
 108 #define ST_12VP                         0x04  /* external 12V programming voltage is present */
 109 #define ST_PMOD                         0x08  /* DS2490 powered from USB and external sources */
 110 #define ST_HALT                         0x10  /* DS2490 is currently halted */
 111 #define ST_IDLE                         0x20  /* DS2490 is currently idle */
 112 #define ST_EPOF                         0x80
 113 /* Status transfer size, 16 bytes status, 16 byte result flags */
 114 #define ST_SIZE                         0x20
 115
 116 /* Result Register flags */
 117 #define RR_DETECT                       0xA5 /* New device detected */
 118 #define RR_NRS                          0x01 /* Reset no presence or ... */
 119 #define RR_SH                           0x02 /* short on reset or set path */
 120 #define RR_APP                          0x04 /* alarming presence on reset */
 121 #define RR_VPP                          0x08 /* 12V expected not seen */
 122 #define RR_CMP                          0x10 /* compare error */
 123 #define RR_CRC                          0x20 /* CRC error detected */
 124 #define RR_RDP                          0x40 /* redirected page */
 125 #define RR_EOS                          0x80 /* end of search error */
 126
 127 #define SPEED_NORMAL                    0x00
 128 #define SPEED_FLEXIBLE                  0x01
 129 #define SPEED_OVERDRIVE                 0x02
 130
 131 #define NUM_EP                          4
 132 #define EP_CONTROL                      0
 133 #define EP_STATUS                       1
 134 #define EP_DATA_OUT                     2
 135 #define EP_DATA_IN                      3
 136
 137 struct ds_device
 138 {
 139         struct list_head        ds_entry;
 140
 141         struct usb_device       *udev;
 142         struct usb_interface    *intf;
 143
 144         int                     ep[NUM_EP];
 145
 146         /* Strong PullUp
 147          * 0: pullup not active, else duration in milliseconds
 148          */
 149         int                     spu_sleep;
 150         /* spu_bit contains COMM_SPU or 0 depending on if the strong pullup
 151          * should be active or not for writes.
 152          */
 153         u16                     spu_bit;
 154
 155         u8                      st_buf[ST_SIZE];
 156         u8                      byte_buf;
 157
 158         struct w1_bus_master    master;
 159 };
 160
 161 struct ds_status
 162 {
 163         u8                      enable;
 164         u8                      speed;
 165         u8                      pullup_dur;
 166         u8                      ppuls_dur;
 167         u8                      pulldown_slew;
 168         u8                      write1_time;
 169         u8                      write0_time;
 170         u8                      reserved0;
 171         u8                      status;
 172         u8                      command0;
 173         u8                      command1;
 174         u8                      command_buffer_status;
 175         u8                      data_out_buffer_status;
 176         u8                      data_in_buffer_status;
 177         u8                      reserved1;
 178         u8                      reserved2;
 179 };
 180
 181 static LIST_HEAD(ds_devices);
 182 static DEFINE_MUTEX(ds_mutex);
 183
 184 static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index)
 185 {
 186         int err;
 187
 188         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 189                         CONTROL_CMD, VENDOR, value, index, NULL, 0, 1000);
 190         if (err < 0) {
 191                 pr_err("Failed to send command control message %x.%x: err=%d.\n",
 192                                 value, index, err);
 193                 return err;
 194         }
 195
 196         return err;
 197 }
 198
 199 static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index)
 200 {
 201         int err;
 202
 203         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 204                         MODE_CMD, VENDOR, value, index, NULL, 0, 1000);
 205         if (err < 0) {
 206                 pr_err("Failed to send mode control message %x.%x: err=%d.\n",
 207                                 value, index, err);
 208                 return err;
 209         }
 210
 211         return err;
 212 }
 213
 214 static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
 215 {
 216         int err;
 217
 218         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 219                         COMM_CMD, VENDOR, value, index, NULL, 0, 1000);
 220         if (err < 0) {
 221                 pr_err("Failed to send control message %x.%x: err=%d.\n",
 222                                 value, index, err);
 223                 return err;
 224         }
 225
 226         return err;
 227 }
 228
 229 static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off)
 230 {
 231         pr_info("%45s: %8x\n", str, buf[off]);
 232 }
 233
 234 static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count)
 235 {
 236         int i;
 237
 238         pr_info("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
 239         for (i=0; i<count; ++i)
 240                 pr_info("%02x ", buf[i]);
 241         pr_info("\n");
 242
 243         if (count >= 16) {
 244                 ds_print_msg(buf, "enable flag", 0);
 245                 ds_print_msg(buf, "1-wire speed", 1);
 246                 ds_print_msg(buf, "strong pullup duration", 2);
 247                 ds_print_msg(buf, "programming pulse duration", 3);
 248                 ds_print_msg(buf, "pulldown slew rate control", 4);
 249                 ds_print_msg(buf, "write-1 low time", 5);
 250                 ds_print_msg(buf, "data sample offset/write-0 recovery time",
 251                         6);
 252                 ds_print_msg(buf, "reserved (test register)", 7);
 253                 ds_print_msg(buf, "device status flags", 8);
 254                 ds_print_msg(buf, "communication command byte 1", 9);
 255                 ds_print_msg(buf, "communication command byte 2", 10);
 256                 ds_print_msg(buf, "communication command buffer status", 11);
 257                 ds_print_msg(buf, "1-wire data output buffer status", 12);
 258                 ds_print_msg(buf, "1-wire data input buffer status", 13);
 259                 ds_print_msg(buf, "reserved", 14);
 260                 ds_print_msg(buf, "reserved", 15);
 261         }
 262         for (i = 16; i < count; ++i) {
 263                 if (buf[i] == RR_DETECT) {
 264                         ds_print_msg(buf, "new device detect", i);
 265                         continue;
 266                 }
 267                 ds_print_msg(buf, "Result Register Value: ", i);
 268                 if (buf[i] & RR_NRS)
 269                         pr_info("NRS: Reset no presence or ...\n");
 270                 if (buf[i] & RR_SH)
 271                         pr_info("SH: short on reset or set path\n");
 272                 if (buf[i] & RR_APP)
 273                         pr_info("APP: alarming presence on reset\n");
 274                 if (buf[i] & RR_VPP)
 275                         pr_info("VPP: 12V expected not seen\n");
 276                 if (buf[i] & RR_CMP)
 277                         pr_info("CMP: compare error\n");
 278                 if (buf[i] & RR_CRC)
 279                         pr_info("CRC: CRC error detected\n");
 280                 if (buf[i] & RR_RDP)
 281                         pr_info("RDP: redirected page\n");
 282                 if (buf[i] & RR_EOS)
 283                         pr_info("EOS: end of search error\n");
 284         }
 285 }
 286
 287 static int ds_recv_status(struct ds_device *dev, struct ds_status *st,
 288                           bool dump)
 289 {
 290         int count, err;
 291
 292         if (st)
 293                 memset(st, 0, sizeof(*st));
 294
 295         count = 0;
 296         err = usb_interrupt_msg(dev->udev,
 297                                 usb_rcvintpipe(dev->udev,
 298                                                dev->ep[EP_STATUS]),
 299                                 dev->st_buf, sizeof(dev->st_buf),
 300                                 &count, 1000);
 301         if (err < 0) {
 302                 pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n",
 303                        dev->ep[EP_STATUS], err);
 304                 return err;
 305         }
 306
 307         if (dump)
 308                 ds_dump_status(dev, dev->st_buf, count);
 309
 310         if (st && count >= sizeof(*st))
 311                 memcpy(st, dev->st_buf, sizeof(*st));
 312
 313         return count;
 314 }
 315
 316 static void ds_reset_device(struct ds_device *dev)
 317 {
 318         ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
 319         /* Always allow strong pullup which allow individual writes to use
 320          * the strong pullup.
 321          */
 322         if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE))
 323                 pr_err("ds_reset_device: Error allowing strong pullup\n");
 324         /* Chip strong pullup time was cleared. */
 325         if (dev->spu_sleep) {
 326                 /* lower 4 bits are 0, see ds_set_pullup */
 327                 u8 del = dev->spu_sleep>>4;
 328                 if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del))
 329                         pr_err("ds_reset_device: Error setting duration\n");
 330         }
 331 }
 332
 333 static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
 334 {
 335         int count, err;
 336
 337         /* Careful on size.  If size is less than what is available in
 338          * the input buffer, the device fails the bulk transfer and
 339          * clears the input buffer.  It could read the maximum size of
 340          * the data buffer, but then do you return the first, last, or
 341          * some set of the middle size bytes?  As long as the rest of
 342          * the code is correct there will be size bytes waiting.  A
 343          * call to ds_wait_status will wait until the device is idle
 344          * and any data to be received would have been available.
 345          */
 346         count = 0;
 347         err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
 348                                 buf, size, &count, 1000);
 349         if (err < 0) {
 350                 pr_info("Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
 351                 usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
 352                 ds_recv_status(dev, NULL, true);
 353                 return err;
 354         }
 355
 356 #if 0
 357         {
 358                 int i;
 359
 360                 printk("%s: count=%d: ", __func__, count);
 361                 for (i=0; i<count; ++i)
 362                         printk("%02x ", buf[i]);
 363                 printk("\n");
 364         }
 365 #endif
 366         return count;
 367 }
 368
 369 static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len)
 370 {
 371         int count, err;
 372
 373         count = 0;
 374         err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000);
 375         if (err < 0) {
 376                 pr_err("Failed to write 1-wire data to ep0x%x: "
 377                         "err=%d.\n", dev->ep[EP_DATA_OUT], err);
 378                 return err;
 379         }
 380
 381         return err;
 382 }
 383
 384 #if 0
 385
 386 int ds_stop_pulse(struct ds_device *dev, int limit)
 387 {
 388         struct ds_status st;
 389         int count = 0, err = 0;
 390
 391         do {
 392                 err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
 393                 if (err)
 394                         break;
 395                 err = ds_send_control(dev, CTL_RESUME_EXE, 0);
 396                 if (err)
 397                         break;
 398                 err = ds_recv_status(dev, &st, false);
 399                 if (err)
 400                         break;
 401
 402                 if ((st.status & ST_SPUA) == 0) {
 403                         err = ds_send_control_mode(dev, MOD_PULSE_EN, 0);
 404                         if (err)
 405                                 break;
 406                 }
 407         } while(++count < limit);
 408
 409         return err;
 410 }
 411
 412 int ds_detect(struct ds_device *dev, struct ds_status *st)
 413 {
 414         int err;
 415
 416         err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
 417         if (err)
 418                 return err;
 419
 420         err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0);
 421         if (err)
 422                 return err;
 423
 424         err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40);
 425         if (err)
 426                 return err;
 427
 428         err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG);
 429         if (err)
 430                 return err;
 431
 432         err = ds_dump_status(dev, st);
 433
 434         return err;
 435 }
 436
 437 #endif  /*  0  */
 438
 439 static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
 440 {
 441         int err, count = 0;
 442
 443         do {
 444                 st->status = 0;
 445                 err = ds_recv_status(dev, st, false);
 446 #if 0
 447                 if (err >= 0) {
 448                         int i;
 449                         printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
 450                         for (i=0; i<err; ++i)
 451                                 printk("%02x ", dev->st_buf[i]);
 452                         printk("\n");
 453                 }
 454 #endif
 455         } while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100);
 456
 457         if (err >= 16 && st->status & ST_EPOF) {
 458                 pr_info("Resetting device after ST_EPOF.\n");
 459                 ds_reset_device(dev);
 460                 /* Always dump the device status. */
 461                 count = 101;
 462         }
 463
 464         /* Dump the status for errors or if there is extended return data.
 465          * The extended status includes new device detection (maybe someone
 466          * can do something with it).
 467          */
 468         if (err > 16 || count >= 100 || err < 0)
 469                 ds_dump_status(dev, dev->st_buf, err);
 470
 471         /* Extended data isn't an error.  Well, a short is, but the dump
 472          * would have already told the user that and we can't do anything
 473          * about it in software anyway.
 474          */
 475         if (count >= 100 || err < 0)
 476                 return -1;
 477         else
 478                 return 0;
 479 }
 480
 481 static int ds_reset(struct ds_device *dev)
 482 {
 483         int err;
 484
 485         /* Other potentionally interesting flags for reset.
 486          *
 487          * COMM_NTF: Return result register feedback.  This could be used to
 488          * detect some conditions such as short, alarming presence, or
 489          * detect if a new device was detected.
 490          *
 491          * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE:
 492          * Select the data transfer rate.
 493          */
 494         err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL);
 495         if (err)
 496                 return err;
 497
 498         return 0;
 499 }
 500
 501 #if 0
 502 static int ds_set_speed(struct ds_device *dev, int speed)
 503 {
 504         int err;
 505
 506         if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE)
 507                 return -EINVAL;
 508
 509         if (speed != SPEED_OVERDRIVE)
 510                 speed = SPEED_FLEXIBLE;
 511
 512         speed &= 0xff;
 513
 514         err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed);
 515         if (err)
 516                 return err;
 517
 518         return err;
 519 }
 520 #endif  /*  0  */
 521
 522 static int ds_set_pullup(struct ds_device *dev, int delay)
 523 {
 524         int err = 0;
 525         u8 del = 1 + (u8)(delay >> 4);
 526         /* Just storing delay would not get the trunication and roundup. */
 527         int ms = del<<4;
 528
 529         /* Enable spu_bit if a delay is set. */
 530         dev->spu_bit = delay ? COMM_SPU : 0;
 531         /* If delay is zero, it has already been disabled, if the time is
 532          * the same as the hardware was last programmed to, there is also
 533          * nothing more to do.  Compare with the recalculated value ms
 534          * rather than del or delay which can have a different value.
 535          */
 536         if (delay == 0 || ms == dev->spu_sleep)
 537                 return err;
 538
 539         err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del);
 540         if (err)
 541                 return err;
 542
 543         dev->spu_sleep = ms;
 544
 545         return err;
 546 }
 547
 548 static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
 549 {
 550         int err;
 551         struct ds_status st;
 552
 553         err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0),
 554                 0);
 555         if (err)
 556                 return err;
 557
 558         ds_wait_status(dev, &st);
 559
 560         err = ds_recv_data(dev, tbit, sizeof(*tbit));
 561         if (err < 0)
 562                 return err;
 563
 564         return 0;
 565 }
 566
 567 #if 0
 568 static int ds_write_bit(struct ds_device *dev, u8 bit)
 569 {
 570         int err;
 571         struct ds_status st;
 572
 573         /* Set COMM_ICP to write without a readback.  Note, this will
 574          * produce one time slot, a down followed by an up with COMM_D
 575          * only determing the timing.
 576          */
 577         err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP |
 578                 (bit ? COMM_D : 0), 0);
 579         if (err)
 580                 return err;
 581
 582         ds_wait_status(dev, &st);
 583
 584         return 0;
 585 }
 586 #endif
 587
 588 static int ds_write_byte(struct ds_device *dev, u8 byte)
 589 {
 590         int err;
 591         struct ds_status st;
 592
 593         err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, byte);
 594         if (err)
 595                 return err;
 596
 597         if (dev->spu_bit)
 598                 msleep(dev->spu_sleep);
 599
 600         err = ds_wait_status(dev, &st);
 601         if (err)
 602                 return err;
 603
 604         err = ds_recv_data(dev, &dev->byte_buf, 1);
 605         if (err < 0)
 606                 return err;
 607
 608         return !(byte == dev->byte_buf);
 609 }
 610
 611 static int ds_read_byte(struct ds_device *dev, u8 *byte)
 612 {
 613         int err;
 614         struct ds_status st;
 615
 616         err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM , 0xff);
 617         if (err)
 618                 return err;
 619
 620         ds_wait_status(dev, &st);
 621
 622         err = ds_recv_data(dev, byte, sizeof(*byte));
 623         if (err < 0)
 624                 return err;
 625
 626         return 0;
 627 }
 628
 629 static int ds_read_block(struct ds_device *dev, u8 *buf, int len)
 630 {
 631         struct ds_status st;
 632         int err;
 633
 634         if (len > 64*1024)
 635                 return -E2BIG;
 636
 637         memset(buf, 0xFF, len);
 638
 639         err = ds_send_data(dev, buf, len);
 640         if (err < 0)
 641                 return err;
 642
 643         err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, len);
 644         if (err)
 645                 return err;
 646
 647         ds_wait_status(dev, &st);
 648
 649         memset(buf, 0x00, len);
 650         err = ds_recv_data(dev, buf, len);
 651
 652         return err;
 653 }
 654
 655 static int ds_write_block(struct ds_device *dev, u8 *buf, int len)
 656 {
 657         int err;
 658         struct ds_status st;
 659
 660         err = ds_send_data(dev, buf, len);
 661         if (err < 0)
 662                 return err;
 663
 664         err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, len);
 665         if (err)
 666                 return err;
 667
 668         if (dev->spu_bit)
 669                 msleep(dev->spu_sleep);
 670
 671         ds_wait_status(dev, &st);
 672
 673         err = ds_recv_data(dev, buf, len);
 674         if (err < 0)
 675                 return err;
 676
 677         return !(err == len);
 678 }
 679
 680 static void ds9490r_search(void *data, struct w1_master *master,
 681         u8 search_type, w1_slave_found_callback callback)
 682 {
 683         /* When starting with an existing id, the first id returned will
 684          * be that device (if it is still on the bus most likely).
 685          *
 686          * If the number of devices found is less than or equal to the
 687          * search_limit, that number of IDs will be returned.  If there are
 688          * more, search_limit IDs will be returned followed by a non-zero
 689          * discrepency value.
 690          */
 691         struct ds_device *dev = data;
 692         int err;
 693         u16 value, index;
 694         struct ds_status st;
 695         int search_limit;
 696         int found = 0;
 697         int i;
 698
 699         /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for
 700          * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time.
 701          */
 702         const unsigned long jtime = msecs_to_jiffies(1000*8/75);
 703         /* FIFO 128 bytes, bulk packet size 64, read a multiple of the
 704          * packet size.
 705          */
 706         const size_t bufsize = 2 * 64;
 707         u64 *buf;
 708
 709         buf = kmalloc(bufsize, GFP_KERNEL);
 710         if (!buf)
 711                 return;
 712
 713         mutex_lock(&master->bus_mutex);
 714
 715         /* address to start searching at */
 716         if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
 717                 goto search_out;
 718         master->search_id = 0;
 719
 720         value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
 721                 COMM_RTS;
 722         search_limit = master->max_slave_count;
 723         if (search_limit > 255)
 724                 search_limit = 0;
 725         index = search_type | (search_limit << 8);
 726         if (ds_send_control(dev, value, index) < 0)
 727                 goto search_out;
 728
 729         do {
 730                 schedule_timeout(jtime);
 731
 732                 err = ds_recv_status(dev, &st, false);
 733                 if (err < 0 || err < sizeof(st))
 734                         break;
 735
 736                 if (st.data_in_buffer_status) {
 737                         /* Bulk in can receive partial ids, but when it does
 738                          * they fail crc and will be discarded anyway.
 739                          * That has only been seen when status in buffer
 740                          * is 0 and bulk is read anyway, so don't read
 741                          * bulk without first checking if status says there
 742                          * is data to read.
 743                          */
 744                         err = ds_recv_data(dev, (u8 *)buf, bufsize);
 745                         if (err < 0)
 746                                 break;
 747                         for (i = 0; i < err/8; ++i) {
 748                                 ++found;
 749                                 if (found <= search_limit)
 750                                         callback(master, buf[i]);
 751                                 /* can't know if there will be a discrepancy
 752                                  * value after until the next id */
 753                                 if (found == search_limit)
 754                                         master->search_id = buf[i];
 755                         }
 756                 }
 757
 758                 if (test_bit(W1_ABORT_SEARCH, &master->flags))
 759                         break;
 760         } while (!(st.status & (ST_IDLE | ST_HALT)));
 761
 762         /* only continue the search if some weren't found */
 763         if (found <= search_limit) {
 764                 master->search_id = 0;
 765         } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) {
 766                 /* Only max_slave_count will be scanned in a search,
 767                  * but it will start where it left off next search
 768                  * until all ids are identified and then it will start
 769                  * over.  A continued search will report the previous
 770                  * last id as the first id (provided it is still on the
 771                  * bus).
 772                  */
 773                 dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, "
 774                         "will continue next search.\n", __func__,
 775                         master->max_slave_count);
 776                 set_bit(W1_WARN_MAX_COUNT, &master->flags);
 777         }
 778 search_out:
 779         mutex_unlock(&master->bus_mutex);
 780         kfree(buf);
 781 }
 782
 783 #if 0
 784 /*
 785  * FIXME: if this disabled code is ever used in the future all ds_send_data()
 786  * calls must be changed to use a DMAable buffer.
 787  */
 788 static int ds_match_access(struct ds_device *dev, u64 init)
 789 {
 790         int err;
 791         struct ds_status st;
 792
 793         err = ds_send_data(dev, (unsigned char *)&init, sizeof(init));
 794         if (err)
 795                 return err;
 796
 797         ds_wait_status(dev, &st);
 798
 799         err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055);
 800         if (err)
 801                 return err;
 802
 803         ds_wait_status(dev, &st);
 804
 805         return 0;
 806 }
 807
 808 static int ds_set_path(struct ds_device *dev, u64 init)
 809 {
 810         int err;
 811         struct ds_status st;
 812         u8 buf[9];
 813
 814         memcpy(buf, &init, 8);
 815         buf[8] = BRANCH_MAIN;
 816
 817         err = ds_send_data(dev, buf, sizeof(buf));
 818         if (err)
 819                 return err;
 820
 821         ds_wait_status(dev, &st);
 822
 823         err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0);
 824         if (err)
 825                 return err;
 826
 827         ds_wait_status(dev, &st);
 828
 829         return 0;
 830 }
 831
 832 #endif  /*  0  */
 833
 834 static u8 ds9490r_touch_bit(void *data, u8 bit)
 835 {
 836         struct ds_device *dev = data;
 837
 838         if (ds_touch_bit(dev, bit, &dev->byte_buf))
 839                 return 0;
 840
 841         return dev->byte_buf;
 842 }
 843
 844 #if 0
 845 static void ds9490r_write_bit(void *data, u8 bit)
 846 {
 847         struct ds_device *dev = data;
 848
 849         ds_write_bit(dev, bit);
 850 }
 851
 852 static u8 ds9490r_read_bit(void *data)
 853 {
 854         struct ds_device *dev = data;
 855         int err;
 856
 857         err = ds_touch_bit(dev, 1, &dev->byte_buf);
 858         if (err)
 859                 return 0;
 860
 861         return dev->byte_buf & 1;
 862 }
 863 #endif
 864
 865 static void ds9490r_write_byte(void *data, u8 byte)
 866 {
 867         struct ds_device *dev = data;
 868
 869         ds_write_byte(dev, byte);
 870 }
 871
 872 static u8 ds9490r_read_byte(void *data)
 873 {
 874         struct ds_device *dev = data;
 875         int err;
 876
 877         err = ds_read_byte(dev, &dev->byte_buf);
 878         if (err)
 879                 return 0;
 880
 881         return dev->byte_buf;
 882 }
 883
 884 static void ds9490r_write_block(void *data, const u8 *buf, int len)
 885 {
 886         struct ds_device *dev = data;
 887         u8 *tbuf;
 888
 889         if (len <= 0)
 890                 return;
 891
 892         tbuf = kmemdup(buf, len, GFP_KERNEL);
 893         if (!tbuf)
 894                 return;
 895
 896         ds_write_block(dev, tbuf, len);
 897
 898         kfree(tbuf);
 899 }
 900
 901 static u8 ds9490r_read_block(void *data, u8 *buf, int len)
 902 {
 903         struct ds_device *dev = data;
 904         int err;
 905         u8 *tbuf;
 906
 907         if (len <= 0)
 908                 return 0;
 909
 910         tbuf = kmalloc(len, GFP_KERNEL);
 911         if (!tbuf)
 912                 return 0;
 913
 914         err = ds_read_block(dev, tbuf, len);
 915         if (err >= 0)
 916                 memcpy(buf, tbuf, len);
 917
 918         kfree(tbuf);
 919
 920         return err >= 0 ? len : 0;
 921 }
 922
 923 static u8 ds9490r_reset(void *data)
 924 {
 925         struct ds_device *dev = data;
 926         int err;
 927
 928         err = ds_reset(dev);
 929         if (err)
 930                 return 1;
 931
 932         return 0;
 933 }
 934
 935 static u8 ds9490r_set_pullup(void *data, int delay)
 936 {
 937         struct ds_device *dev = data;
 938
 939         if (ds_set_pullup(dev, delay))
 940                 return 1;
 941
 942         return 0;
 943 }
 944
 945 static int ds_w1_init(struct ds_device *dev)
 946 {
 947         memset(&dev->master, 0, sizeof(struct w1_bus_master));
 948
 949         /* Reset the device as it can be in a bad state.
 950          * This is necessary because a block write will wait for data
 951          * to be placed in the output buffer and block any later
 952          * commands which will keep accumulating and the device will
 953          * not be idle.  Another case is removing the ds2490 module
 954          * while a bus search is in progress, somehow a few commands
 955          * get through, but the input transfers fail leaving data in
 956          * the input buffer.  This will cause the next read to fail
 957          * see the note in ds_recv_data.
 958          */
 959         ds_reset_device(dev);
 960
 961         dev->master.data        = dev;
 962         dev->master.touch_bit   = &ds9490r_touch_bit;
 963         /* read_bit and write_bit in w1_bus_master are expected to set and
 964          * sample the line level.  For write_bit that means it is expected to
 965          * set it to that value and leave it there.  ds2490 only supports an
 966          * individual time slot at the lowest level.  The requirement from
 967          * pulling the bus state down to reading the state is 15us, something
 968          * that isn't realistic on the USB bus anyway.
 969         dev->master.read_bit    = &ds9490r_read_bit;
 970         dev->master.write_bit   = &ds9490r_write_bit;
 971         */
 972         dev->master.read_byte   = &ds9490r_read_byte;
 973         dev->master.write_byte  = &ds9490r_write_byte;
 974         dev->master.read_block  = &ds9490r_read_block;
 975         dev->master.write_block = &ds9490r_write_block;
 976         dev->master.reset_bus   = &ds9490r_reset;
 977         dev->master.set_pullup  = &ds9490r_set_pullup;
 978         dev->master.search      = &ds9490r_search;
 979
 980         return w1_add_master_device(&dev->master);
 981 }
 982
 983 static void ds_w1_fini(struct ds_device *dev)
 984 {
 985         w1_remove_master_device(&dev->master);
 986 }
 987
 988 static int ds_probe(struct usb_interface *intf,
 989                     const struct usb_device_id *udev_id)
 990 {
 991         struct usb_device *udev = interface_to_usbdev(intf);
 992         struct usb_endpoint_descriptor *endpoint;
 993         struct usb_host_interface *iface_desc;
 994         struct ds_device *dev;
 995         int i, err, alt;
 996
 997         dev = kzalloc(sizeof(struct ds_device), GFP_KERNEL);
 998         if (!dev) {
 999                 pr_info("Failed to allocate new DS9490R structure.\n");
1000                 return -ENOMEM;
1001         }
1002         dev->udev = usb_get_dev(udev);
1003         if (!dev->udev) {
1004                 err = -ENOMEM;
1005                 goto err_out_free;
1006         }
1007         memset(dev->ep, 0, sizeof(dev->ep));
1008
1009         usb_set_intfdata(intf, dev);
1010
1011         err = usb_reset_configuration(dev->udev);
1012         if (err) {
1013                 dev_err(&dev->udev->dev,
1014                         "Failed to reset configuration: err=%d.\n", err);
1015                 goto err_out_clear;
1016         }
1017
1018         /* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */
1019         alt = 3;
1020         err = usb_set_interface(dev->udev,
1021                 intf->altsetting[alt].desc.bInterfaceNumber, alt);
1022         if (err) {
1023                 dev_err(&dev->udev->dev, "Failed to set alternative setting %d "
1024                         "for %d interface: err=%d.\n", alt,
1025                         intf->altsetting[alt].desc.bInterfaceNumber, err);
1026                 goto err_out_clear;
1027         }
1028
1029         iface_desc = &intf->altsetting[alt];
1030         if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
1031                 pr_info("Num endpoints=%d. It is not DS9490R.\n",
1032                         iface_desc->desc.bNumEndpoints);
1033                 err = -EINVAL;
1034                 goto err_out_clear;
1035         }
1036
1037         /*
1038          * This loop doesn'd show control 0 endpoint,
1039          * so we will fill only 1-3 endpoints entry.
1040          */
1041         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
1042                 endpoint = &iface_desc->endpoint[i].desc;
1043
1044                 dev->ep[i+1] = endpoint->bEndpointAddress;
1045 #if 0
1046                 printk("%d: addr=%x, size=%d, dir=%s, type=%x\n",
1047                         i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
1048                         (endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
1049                         endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
1050 #endif
1051         }
1052
1053         err = ds_w1_init(dev);
1054         if (err)
1055                 goto err_out_clear;
1056
1057         mutex_lock(&ds_mutex);
1058         list_add_tail(&dev->ds_entry, &ds_devices);
1059         mutex_unlock(&ds_mutex);
1060
1061         return 0;
1062
1063 err_out_clear:
1064         usb_set_intfdata(intf, NULL);
1065         usb_put_dev(dev->udev);
1066 err_out_free:
1067         kfree(dev);
1068         return err;
1069 }
1070
1071 static void ds_disconnect(struct usb_interface *intf)
1072 {
1073         struct ds_device *dev;
1074
1075         dev = usb_get_intfdata(intf);
1076         if (!dev)
1077                 return;
1078
1079         mutex_lock(&ds_mutex);
1080         list_del(&dev->ds_entry);
1081         mutex_unlock(&ds_mutex);
1082
1083         ds_w1_fini(dev);
1084
1085         usb_set_intfdata(intf, NULL);
1086
1087         usb_put_dev(dev->udev);
1088         kfree(dev);
1089 }
1090
1091 static const struct usb_device_id ds_id_table[] = {
1092         { USB_DEVICE(0x04fa, 0x2490) },
1093         { },
1094 };
1095 MODULE_DEVICE_TABLE(usb, ds_id_table);
1096
1097 static struct usb_driver ds_driver = {
1098         .name =         "DS9490R",
1099         .probe =        ds_probe,
1100         .disconnect =   ds_disconnect,
1101         .id_table =     ds_id_table,
1102 };
1103 module_usb_driver(ds_driver);
1104
1105 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
1106 MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)");
1107 MODULE_LICENSE("GPL");