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