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 "../w1_int.h"
  29 #include "../w1.h"
  30
  31 /* USB Standard */
  32 /* USB Control request vendor type */
  33 #define VENDOR                          0x40
  34
  35 /* COMMAND TYPE CODES */
  36 #define CONTROL_CMD                     0x00
  37 #define COMM_CMD                        0x01
  38 #define MODE_CMD                        0x02
  39
  40 /* CONTROL COMMAND CODES */
  41 #define CTL_RESET_DEVICE                0x0000
  42 #define CTL_START_EXE                   0x0001
  43 #define CTL_RESUME_EXE                  0x0002
  44 #define CTL_HALT_EXE_IDLE               0x0003
  45 #define CTL_HALT_EXE_DONE               0x0004
  46 #define CTL_FLUSH_COMM_CMDS             0x0007
  47 #define CTL_FLUSH_RCV_BUFFER            0x0008
  48 #define CTL_FLUSH_XMT_BUFFER            0x0009
  49 #define CTL_GET_COMM_CMDS               0x000A
  50
  51 /* MODE COMMAND CODES */
  52 #define MOD_PULSE_EN                    0x0000
  53 #define MOD_SPEED_CHANGE_EN             0x0001
  54 #define MOD_1WIRE_SPEED                 0x0002
  55 #define MOD_STRONG_PU_DURATION          0x0003
  56 #define MOD_PULLDOWN_SLEWRATE           0x0004
  57 #define MOD_PROG_PULSE_DURATION         0x0005
  58 #define MOD_WRITE1_LOWTIME              0x0006
  59 #define MOD_DSOW0_TREC                  0x0007
  60
  61 /* COMMUNICATION COMMAND CODES */
  62 #define COMM_ERROR_ESCAPE               0x0601
  63 #define COMM_SET_DURATION               0x0012
  64 #define COMM_BIT_IO                     0x0020
  65 #define COMM_PULSE                      0x0030
  66 #define COMM_1_WIRE_RESET               0x0042
  67 #define COMM_BYTE_IO                    0x0052
  68 #define COMM_MATCH_ACCESS               0x0064
  69 #define COMM_BLOCK_IO                   0x0074
  70 #define COMM_READ_STRAIGHT              0x0080
  71 #define COMM_DO_RELEASE                 0x6092
  72 #define COMM_SET_PATH                   0x00A2
  73 #define COMM_WRITE_SRAM_PAGE            0x00B2
  74 #define COMM_WRITE_EPROM                0x00C4
  75 #define COMM_READ_CRC_PROT_PAGE         0x00D4
  76 #define COMM_READ_REDIRECT_PAGE_CRC     0x21E4
  77 #define COMM_SEARCH_ACCESS              0x00F4
  78
  79 /* Communication command bits */
  80 #define COMM_TYPE                       0x0008
  81 #define COMM_SE                         0x0008
  82 #define COMM_D                          0x0008
  83 #define COMM_Z                          0x0008
  84 #define COMM_CH                         0x0008
  85 #define COMM_SM                         0x0008
  86 #define COMM_R                          0x0008
  87 #define COMM_IM                         0x0001
  88
  89 #define COMM_PS                         0x4000
  90 #define COMM_PST                        0x4000
  91 #define COMM_CIB                        0x4000
  92 #define COMM_RTS                        0x4000
  93 #define COMM_DT                         0x2000
  94 #define COMM_SPU                        0x1000
  95 #define COMM_F                          0x0800
  96 #define COMM_NTF                        0x0400
  97 #define COMM_ICP                        0x0200
  98 #define COMM_RST                        0x0100
  99
 100 #define PULSE_PROG                      0x01
 101 #define PULSE_SPUE                      0x02
 102
 103 #define BRANCH_MAIN                     0xCC
 104 #define BRANCH_AUX                      0x33
 105
 106 /* Status flags */
 107 #define ST_SPUA                         0x01  /* Strong Pull-up is active */
 108 #define ST_PRGA                         0x02  /* 12V programming pulse is being generated */
 109 #define ST_12VP                         0x04  /* external 12V programming voltage is present */
 110 #define ST_PMOD                         0x08  /* DS2490 powered from USB and external sources */
 111 #define ST_HALT                         0x10  /* DS2490 is currently halted */
 112 #define ST_IDLE                         0x20  /* DS2490 is currently idle */
 113 #define ST_EPOF                         0x80
 114 /* Status transfer size, 16 bytes status, 16 byte result flags */
 115 #define ST_SIZE                         0x20
 116
 117 /* Result Register flags */
 118 #define RR_DETECT                       0xA5 /* New device detected */
 119 #define RR_NRS                          0x01 /* Reset no presence or ... */
 120 #define RR_SH                           0x02 /* short on reset or set path */
 121 #define RR_APP                          0x04 /* alarming presence on reset */
 122 #define RR_VPP                          0x08 /* 12V expected not seen */
 123 #define RR_CMP                          0x10 /* compare error */
 124 #define RR_CRC                          0x20 /* CRC error detected */
 125 #define RR_RDP                          0x40 /* redirected page */
 126 #define RR_EOS                          0x80 /* end of search error */
 127
 128 #define SPEED_NORMAL                    0x00
 129 #define SPEED_FLEXIBLE                  0x01
 130 #define SPEED_OVERDRIVE                 0x02
 131
 132 #define NUM_EP                          4
 133 #define EP_CONTROL                      0
 134 #define EP_STATUS                       1
 135 #define EP_DATA_OUT                     2
 136 #define EP_DATA_IN                      3
 137
 138 struct ds_device
 139 {
 140         struct list_head        ds_entry;
 141
 142         struct usb_device       *udev;
 143         struct usb_interface    *intf;
 144
 145         int                     ep[NUM_EP];
 146
 147         /* Strong PullUp
 148          * 0: pullup not active, else duration in milliseconds
 149          */
 150         int                     spu_sleep;
 151         /* spu_bit contains COMM_SPU or 0 depending on if the strong pullup
 152          * should be active or not for writes.
 153          */
 154         u16                     spu_bit;
 155
 156         struct w1_bus_master    master;
 157 };
 158
 159 struct ds_status
 160 {
 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
 180 static struct usb_device_id ds_id_table [] = {
 181         { USB_DEVICE(0x04fa, 0x2490) },
 182         { },
 183 };
 184 MODULE_DEVICE_TABLE(usb, ds_id_table);
 185
 186 static int ds_probe(struct usb_interface *, const struct usb_device_id *);
 187 static void ds_disconnect(struct usb_interface *);
 188
 189 static int ds_send_control(struct ds_device *, u16, u16);
 190 static int ds_send_control_cmd(struct ds_device *, u16, u16);
 191
 192 static LIST_HEAD(ds_devices);
 193 static DEFINE_MUTEX(ds_mutex);
 194
 195 static struct usb_driver ds_driver = {
 196         .name =         "DS9490R",
 197         .probe =        ds_probe,
 198         .disconnect =   ds_disconnect,
 199         .id_table =     ds_id_table,
 200 };
 201
 202 static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index)
 203 {
 204         int err;
 205
 206         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 207                         CONTROL_CMD, VENDOR, value, index, NULL, 0, 1000);
 208         if (err < 0) {
 209                 pr_err("Failed to send command control message %x.%x: err=%d.\n",
 210                                 value, index, err);
 211                 return err;
 212         }
 213
 214         return err;
 215 }
 216
 217 static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index)
 218 {
 219         int err;
 220
 221         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 222                         MODE_CMD, VENDOR, value, index, NULL, 0, 1000);
 223         if (err < 0) {
 224                 pr_err("Failed to send mode control message %x.%x: err=%d.\n",
 225                                 value, index, err);
 226                 return err;
 227         }
 228
 229         return err;
 230 }
 231
 232 static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
 233 {
 234         int err;
 235
 236         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 237                         COMM_CMD, VENDOR, value, index, NULL, 0, 1000);
 238         if (err < 0) {
 239                 pr_err("Failed to send control message %x.%x: err=%d.\n",
 240                                 value, index, err);
 241                 return err;
 242         }
 243
 244         return err;
 245 }
 246
 247 static int ds_recv_status_nodump(struct ds_device *dev, struct ds_status *st,
 248                                  unsigned char *buf, int size)
 249 {
 250         int count, err;
 251
 252         memset(st, 0, sizeof(*st));
 253
 254         count = 0;
 255         err = usb_interrupt_msg(dev->udev, usb_rcvintpipe(dev->udev,
 256                 dev->ep[EP_STATUS]), buf, size, &count, 1000);
 257         if (err < 0) {
 258                 pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n",
 259                        dev->ep[EP_STATUS], err);
 260                 return err;
 261         }
 262
 263         if (count >= sizeof(*st))
 264                 memcpy(st, buf, sizeof(*st));
 265
 266         return count;
 267 }
 268
 269 static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off)
 270 {
 271         pr_info("%45s: %8x\n", str, buf[off]);
 272 }
 273
 274 static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count)
 275 {
 276         int i;
 277
 278         pr_info("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
 279         for (i=0; i<count; ++i)
 280                 pr_info("%02x ", buf[i]);
 281         pr_info("\n");
 282
 283         if (count >= 16) {
 284                 ds_print_msg(buf, "enable flag", 0);
 285                 ds_print_msg(buf, "1-wire speed", 1);
 286                 ds_print_msg(buf, "strong pullup duration", 2);
 287                 ds_print_msg(buf, "programming pulse duration", 3);
 288                 ds_print_msg(buf, "pulldown slew rate control", 4);
 289                 ds_print_msg(buf, "write-1 low time", 5);
 290                 ds_print_msg(buf, "data sample offset/write-0 recovery time",
 291                         6);
 292                 ds_print_msg(buf, "reserved (test register)", 7);
 293                 ds_print_msg(buf, "device status flags", 8);
 294                 ds_print_msg(buf, "communication command byte 1", 9);
 295                 ds_print_msg(buf, "communication command byte 2", 10);
 296                 ds_print_msg(buf, "communication command buffer status", 11);
 297                 ds_print_msg(buf, "1-wire data output buffer status", 12);
 298                 ds_print_msg(buf, "1-wire data input buffer status", 13);
 299                 ds_print_msg(buf, "reserved", 14);
 300                 ds_print_msg(buf, "reserved", 15);
 301         }
 302         for (i = 16; i < count; ++i) {
 303                 if (buf[i] == RR_DETECT) {
 304                         ds_print_msg(buf, "new device detect", i);
 305                         continue;
 306                 }
 307                 ds_print_msg(buf, "Result Register Value: ", i);
 308                 if (buf[i] & RR_NRS)
 309                         pr_info("NRS: Reset no presence or ...\n");
 310                 if (buf[i] & RR_SH)
 311                         pr_info("SH: short on reset or set path\n");
 312                 if (buf[i] & RR_APP)
 313                         pr_info("APP: alarming presence on reset\n");
 314                 if (buf[i] & RR_VPP)
 315                         pr_info("VPP: 12V expected not seen\n");
 316                 if (buf[i] & RR_CMP)
 317                         pr_info("CMP: compare error\n");
 318                 if (buf[i] & RR_CRC)
 319                         pr_info("CRC: CRC error detected\n");
 320                 if (buf[i] & RR_RDP)
 321                         pr_info("RDP: redirected page\n");
 322                 if (buf[i] & RR_EOS)
 323                         pr_info("EOS: end of search error\n");
 324         }
 325 }
 326
 327 static void ds_reset_device(struct ds_device *dev)
 328 {
 329         ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
 330         /* Always allow strong pullup which allow individual writes to use
 331          * the strong pullup.
 332          */
 333         if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE))
 334                 pr_err("ds_reset_device: Error allowing strong pullup\n");
 335         /* Chip strong pullup time was cleared. */
 336         if (dev->spu_sleep) {
 337                 /* lower 4 bits are 0, see ds_set_pullup */
 338                 u8 del = dev->spu_sleep>>4;
 339                 if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del))
 340                         pr_err("ds_reset_device: Error setting duration\n");
 341         }
 342 }
 343
 344 static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
 345 {
 346         int count, err;
 347         struct ds_status st;
 348
 349         /* Careful on size.  If size is less than what is available in
 350          * the input buffer, the device fails the bulk transfer and
 351          * clears the input buffer.  It could read the maximum size of
 352          * the data buffer, but then do you return the first, last, or
 353          * some set of the middle size bytes?  As long as the rest of
 354          * the code is correct there will be size bytes waiting.  A
 355          * call to ds_wait_status will wait until the device is idle
 356          * and any data to be received would have been available.
 357          */
 358         count = 0;
 359         err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
 360                                 buf, size, &count, 1000);
 361         if (err < 0) {
 362                 u8 buf[ST_SIZE];
 363                 int count;
 364
 365                 pr_info("Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
 366                 usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
 367
 368                 count = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
 369                 ds_dump_status(dev, buf, count);
 370                 return err;
 371         }
 372
 373 #if 0
 374         {
 375                 int i;
 376
 377                 printk("%s: count=%d: ", __func__, count);
 378                 for (i=0; i<count; ++i)
 379                         printk("%02x ", buf[i]);
 380                 printk("\n");
 381         }
 382 #endif
 383         return count;
 384 }
 385
 386 static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len)
 387 {
 388         int count, err;
 389
 390         count = 0;
 391         err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000);
 392         if (err < 0) {
 393                 pr_err("Failed to write 1-wire data to ep0x%x: "
 394                         "err=%d.\n", dev->ep[EP_DATA_OUT], err);
 395                 return err;
 396         }
 397
 398         return err;
 399 }
 400
 401 #if 0
 402
 403 int ds_stop_pulse(struct ds_device *dev, int limit)
 404 {
 405         struct ds_status st;
 406         int count = 0, err = 0;
 407         u8 buf[ST_SIZE];
 408
 409         do {
 410                 err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
 411                 if (err)
 412                         break;
 413                 err = ds_send_control(dev, CTL_RESUME_EXE, 0);
 414                 if (err)
 415                         break;
 416                 err = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
 417                 if (err)
 418                         break;
 419
 420                 if ((st.status & ST_SPUA) == 0) {
 421                         err = ds_send_control_mode(dev, MOD_PULSE_EN, 0);
 422                         if (err)
 423                                 break;
 424                 }
 425         } while(++count < limit);
 426
 427         return err;
 428 }
 429
 430 int ds_detect(struct ds_device *dev, struct ds_status *st)
 431 {
 432         int err;
 433
 434         err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
 435         if (err)
 436                 return err;
 437
 438         err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0);
 439         if (err)
 440                 return err;
 441
 442         err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40);
 443         if (err)
 444                 return err;
 445
 446         err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG);
 447         if (err)
 448                 return err;
 449
 450         err = ds_dump_status(dev, st);
 451
 452         return err;
 453 }
 454
 455 #endif  /*  0  */
 456
 457 static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
 458 {
 459         u8 buf[ST_SIZE];
 460         int err, count = 0;
 461
 462         do {
 463                 st->status = 0;
 464                 err = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
 465 #if 0
 466                 if (err >= 0) {
 467                         int i;
 468                         printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
 469                         for (i=0; i<err; ++i)
 470                                 printk("%02x ", buf[i]);
 471                         printk("\n");
 472                 }
 473 #endif
 474         } while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100);
 475
 476         if (err >= 16 && st->status & ST_EPOF) {
 477                 pr_info("Resetting device after ST_EPOF.\n");
 478                 ds_reset_device(dev);
 479                 /* Always dump the device status. */
 480                 count = 101;
 481         }
 482
 483         /* Dump the status for errors or if there is extended return data.
 484          * The extended status includes new device detection (maybe someone
 485          * can do something with it).
 486          */
 487         if (err > 16 || count >= 100 || err < 0)
 488                 ds_dump_status(dev, buf, err);
 489
 490         /* Extended data isn't an error.  Well, a short is, but the dump
 491          * would have already told the user that and we can't do anything
 492          * about it in software anyway.
 493          */
 494         if (count >= 100 || err < 0)
 495                 return -1;
 496         else
 497                 return 0;
 498 }
 499
 500 static int ds_reset(struct ds_device *dev)
 501 {
 502         int err;
 503
 504         /* Other potentionally interesting flags for reset.
 505          *
 506          * COMM_NTF: Return result register feedback.  This could be used to
 507          * detect some conditions such as short, alarming presence, or
 508          * detect if a new device was detected.
 509          *
 510          * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE:
 511          * Select the data transfer rate.
 512          */
 513         err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL);
 514         if (err)
 515                 return err;
 516
 517         return 0;
 518 }
 519
 520 #if 0
 521 static int ds_set_speed(struct ds_device *dev, int speed)
 522 {
 523         int err;
 524
 525         if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE)
 526                 return -EINVAL;
 527
 528         if (speed != SPEED_OVERDRIVE)
 529                 speed = SPEED_FLEXIBLE;
 530
 531         speed &= 0xff;
 532
 533         err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed);
 534         if (err)
 535                 return err;
 536
 537         return err;
 538 }
 539 #endif  /*  0  */
 540
 541 static int ds_set_pullup(struct ds_device *dev, int delay)
 542 {
 543         int err = 0;
 544         u8 del = 1 + (u8)(delay >> 4);
 545         /* Just storing delay would not get the trunication and roundup. */
 546         int ms = del<<4;
 547
 548         /* Enable spu_bit if a delay is set. */
 549         dev->spu_bit = delay ? COMM_SPU : 0;
 550         /* If delay is zero, it has already been disabled, if the time is
 551          * the same as the hardware was last programmed to, there is also
 552          * nothing more to do.  Compare with the recalculated value ms
 553          * rather than del or delay which can have a different value.
 554          */
 555         if (delay == 0 || ms == dev->spu_sleep)
 556                 return err;
 557
 558         err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del);
 559         if (err)
 560                 return err;
 561
 562         dev->spu_sleep = ms;
 563
 564         return err;
 565 }
 566
 567 static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
 568 {
 569         int err;
 570         struct ds_status st;
 571
 572         err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0),
 573                 0);
 574         if (err)
 575                 return err;
 576
 577         ds_wait_status(dev, &st);
 578
 579         err = ds_recv_data(dev, tbit, sizeof(*tbit));
 580         if (err < 0)
 581                 return err;
 582
 583         return 0;
 584 }
 585
 586 #if 0
 587 static int ds_write_bit(struct ds_device *dev, u8 bit)
 588 {
 589         int err;
 590         struct ds_status st;
 591
 592         /* Set COMM_ICP to write without a readback.  Note, this will
 593          * produce one time slot, a down followed by an up with COMM_D
 594          * only determing the timing.
 595          */
 596         err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP |
 597                 (bit ? COMM_D : 0), 0);
 598         if (err)
 599                 return err;
 600
 601         ds_wait_status(dev, &st);
 602
 603         return 0;
 604 }
 605 #endif
 606
 607 static int ds_write_byte(struct ds_device *dev, u8 byte)
 608 {
 609         int err;
 610         struct ds_status st;
 611         u8 rbyte;
 612
 613         err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, byte);
 614         if (err)
 615                 return err;
 616
 617         if (dev->spu_bit)
 618                 msleep(dev->spu_sleep);
 619
 620         err = ds_wait_status(dev, &st);
 621         if (err)
 622                 return err;
 623
 624         err = ds_recv_data(dev, &rbyte, sizeof(rbyte));
 625         if (err < 0)
 626                 return err;
 627
 628         return !(byte == rbyte);
 629 }
 630
 631 static int ds_read_byte(struct ds_device *dev, u8 *byte)
 632 {
 633         int err;
 634         struct ds_status st;
 635
 636         err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM , 0xff);
 637         if (err)
 638                 return err;
 639
 640         ds_wait_status(dev, &st);
 641
 642         err = ds_recv_data(dev, byte, sizeof(*byte));
 643         if (err < 0)
 644                 return err;
 645
 646         return 0;
 647 }
 648
 649 static int ds_read_block(struct ds_device *dev, u8 *buf, int len)
 650 {
 651         struct ds_status st;
 652         int err;
 653
 654         if (len > 64*1024)
 655                 return -E2BIG;
 656
 657         memset(buf, 0xFF, len);
 658
 659         err = ds_send_data(dev, buf, len);
 660         if (err < 0)
 661                 return err;
 662
 663         err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, len);
 664         if (err)
 665                 return err;
 666
 667         ds_wait_status(dev, &st);
 668
 669         memset(buf, 0x00, len);
 670         err = ds_recv_data(dev, buf, len);
 671
 672         return err;
 673 }
 674
 675 static int ds_write_block(struct ds_device *dev, u8 *buf, int len)
 676 {
 677         int err;
 678         struct ds_status st;
 679
 680         err = ds_send_data(dev, buf, len);
 681         if (err < 0)
 682                 return err;
 683
 684         err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, len);
 685         if (err)
 686                 return err;
 687
 688         if (dev->spu_bit)
 689                 msleep(dev->spu_sleep);
 690
 691         ds_wait_status(dev, &st);
 692
 693         err = ds_recv_data(dev, buf, len);
 694         if (err < 0)
 695                 return err;
 696
 697         return !(err == len);
 698 }
 699
 700 static void ds9490r_search(void *data, struct w1_master *master,
 701         u8 search_type, w1_slave_found_callback callback)
 702 {
 703         /* When starting with an existing id, the first id returned will
 704          * be that device (if it is still on the bus most likely).
 705          *
 706          * If the number of devices found is less than or equal to the
 707          * search_limit, that number of IDs will be returned.  If there are
 708          * more, search_limit IDs will be returned followed by a non-zero
 709          * discrepency value.
 710          */
 711         struct ds_device *dev = data;
 712         int err;
 713         u16 value, index;
 714         struct ds_status st;
 715         u8 st_buf[ST_SIZE];
 716         int search_limit;
 717         int found = 0;
 718         int i;
 719
 720         /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for
 721          * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time.
 722          */
 723         const unsigned long jtime = msecs_to_jiffies(1000*8/75);
 724         /* FIFO 128 bytes, bulk packet size 64, read a multiple of the
 725          * packet size.
 726          */
 727         u64 buf[2*64/8];
 728
 729         mutex_lock(&master->bus_mutex);
 730
 731         /* address to start searching at */
 732         if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
 733                 goto search_out;
 734         master->search_id = 0;
 735
 736         value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
 737                 COMM_RTS;
 738         search_limit = master->max_slave_count;
 739         if (search_limit > 255)
 740                 search_limit = 0;
 741         index = search_type | (search_limit << 8);
 742         if (ds_send_control(dev, value, index) < 0)
 743                 goto search_out;
 744
 745         do {
 746                 schedule_timeout(jtime);
 747
 748                 if (ds_recv_status_nodump(dev, &st, st_buf, sizeof(st_buf)) <
 749                         sizeof(st)) {
 750                         break;
 751                 }
 752
 753                 if (st.data_in_buffer_status) {
 754                         /* Bulk in can receive partial ids, but when it does
 755                          * they fail crc and will be discarded anyway.
 756                          * That has only been seen when status in buffer
 757                          * is 0 and bulk is read anyway, so don't read
 758                          * bulk without first checking if status says there
 759                          * is data to read.
 760                          */
 761                         err = ds_recv_data(dev, (u8 *)buf, sizeof(buf));
 762                         if (err < 0)
 763                                 break;
 764                         for (i = 0; i < err/8; ++i) {
 765                                 ++found;
 766                                 if (found <= search_limit)
 767                                         callback(master, buf[i]);
 768                                 /* can't know if there will be a discrepancy
 769                                  * value after until the next id */
 770                                 if (found == search_limit)
 771                                         master->search_id = buf[i];
 772                         }
 773                 }
 774
 775                 if (test_bit(W1_ABORT_SEARCH, &master->flags))
 776                         break;
 777         } while (!(st.status & (ST_IDLE | ST_HALT)));
 778
 779         /* only continue the search if some weren't found */
 780         if (found <= search_limit) {
 781                 master->search_id = 0;
 782         } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) {
 783                 /* Only max_slave_count will be scanned in a search,
 784                  * but it will start where it left off next search
 785                  * until all ids are identified and then it will start
 786                  * over.  A continued search will report the previous
 787                  * last id as the first id (provided it is still on the
 788                  * bus).
 789                  */
 790                 dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, "
 791                         "will continue next search.\n", __func__,
 792                         master->max_slave_count);
 793                 set_bit(W1_WARN_MAX_COUNT, &master->flags);
 794         }
 795 search_out:
 796         mutex_unlock(&master->bus_mutex);
 797 }
 798
 799 #if 0
 800 static int ds_match_access(struct ds_device *dev, u64 init)
 801 {
 802         int err;
 803         struct ds_status st;
 804
 805         err = ds_send_data(dev, (unsigned char *)&init, sizeof(init));
 806         if (err)
 807                 return err;
 808
 809         ds_wait_status(dev, &st);
 810
 811         err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055);
 812         if (err)
 813                 return err;
 814
 815         ds_wait_status(dev, &st);
 816
 817         return 0;
 818 }
 819
 820 static int ds_set_path(struct ds_device *dev, u64 init)
 821 {
 822         int err;
 823         struct ds_status st;
 824         u8 buf[9];
 825
 826         memcpy(buf, &init, 8);
 827         buf[8] = BRANCH_MAIN;
 828
 829         err = ds_send_data(dev, buf, sizeof(buf));
 830         if (err)
 831                 return err;
 832
 833         ds_wait_status(dev, &st);
 834
 835         err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0);
 836         if (err)
 837                 return err;
 838
 839         ds_wait_status(dev, &st);
 840
 841         return 0;
 842 }
 843
 844 #endif  /*  0  */
 845
 846 static u8 ds9490r_touch_bit(void *data, u8 bit)
 847 {
 848         u8 ret;
 849         struct ds_device *dev = data;
 850
 851         if (ds_touch_bit(dev, bit, &ret))
 852                 return 0;
 853
 854         return ret;
 855 }
 856
 857 #if 0
 858 static void ds9490r_write_bit(void *data, u8 bit)
 859 {
 860         struct ds_device *dev = data;
 861
 862         ds_write_bit(dev, bit);
 863 }
 864
 865 static u8 ds9490r_read_bit(void *data)
 866 {
 867         struct ds_device *dev = data;
 868         int err;
 869         u8 bit = 0;
 870
 871         err = ds_touch_bit(dev, 1, &bit);
 872         if (err)
 873                 return 0;
 874
 875         return bit & 1;
 876 }
 877 #endif
 878
 879 static void ds9490r_write_byte(void *data, u8 byte)
 880 {
 881         struct ds_device *dev = data;
 882
 883         ds_write_byte(dev, byte);
 884 }
 885
 886 static u8 ds9490r_read_byte(void *data)
 887 {
 888         struct ds_device *dev = data;
 889         int err;
 890         u8 byte = 0;
 891
 892         err = ds_read_byte(dev, &byte);
 893         if (err)
 894                 return 0;
 895
 896         return byte;
 897 }
 898
 899 static void ds9490r_write_block(void *data, const u8 *buf, int len)
 900 {
 901         struct ds_device *dev = data;
 902
 903         ds_write_block(dev, (u8 *)buf, len);
 904 }
 905
 906 static u8 ds9490r_read_block(void *data, u8 *buf, int len)
 907 {
 908         struct ds_device *dev = data;
 909         int err;
 910
 911         err = ds_read_block(dev, buf, len);
 912         if (err < 0)
 913                 return 0;
 914
 915         return len;
 916 }
 917
 918 static u8 ds9490r_reset(void *data)
 919 {
 920         struct ds_device *dev = data;
 921         int err;
 922
 923         err = ds_reset(dev);
 924         if (err)
 925                 return 1;
 926
 927         return 0;
 928 }
 929
 930 static u8 ds9490r_set_pullup(void *data, int delay)
 931 {
 932         struct ds_device *dev = data;
 933
 934         if (ds_set_pullup(dev, delay))
 935                 return 1;
 936
 937         return 0;
 938 }
 939
 940 static int ds_w1_init(struct ds_device *dev)
 941 {
 942         memset(&dev->master, 0, sizeof(struct w1_bus_master));
 943
 944         /* Reset the device as it can be in a bad state.
 945          * This is necessary because a block write will wait for data
 946          * to be placed in the output buffer and block any later
 947          * commands which will keep accumulating and the device will
 948          * not be idle.  Another case is removing the ds2490 module
 949          * while a bus search is in progress, somehow a few commands
 950          * get through, but the input transfers fail leaving data in
 951          * the input buffer.  This will cause the next read to fail
 952          * see the note in ds_recv_data.
 953          */
 954         ds_reset_device(dev);
 955
 956         dev->master.data        = dev;
 957         dev->master.touch_bit   = &ds9490r_touch_bit;
 958         /* read_bit and write_bit in w1_bus_master are expected to set and
 959          * sample the line level.  For write_bit that means it is expected to
 960          * set it to that value and leave it there.  ds2490 only supports an
 961          * individual time slot at the lowest level.  The requirement from
 962          * pulling the bus state down to reading the state is 15us, something
 963          * that isn't realistic on the USB bus anyway.
 964         dev->master.read_bit    = &ds9490r_read_bit;
 965         dev->master.write_bit   = &ds9490r_write_bit;
 966         */
 967         dev->master.read_byte   = &ds9490r_read_byte;
 968         dev->master.write_byte  = &ds9490r_write_byte;
 969         dev->master.read_block  = &ds9490r_read_block;
 970         dev->master.write_block = &ds9490r_write_block;
 971         dev->master.reset_bus   = &ds9490r_reset;
 972         dev->master.set_pullup  = &ds9490r_set_pullup;
 973         dev->master.search      = &ds9490r_search;
 974
 975         return w1_add_master_device(&dev->master);
 976 }
 977
 978 static void ds_w1_fini(struct ds_device *dev)
 979 {
 980         w1_remove_master_device(&dev->master);
 981 }
 982
 983 static int ds_probe(struct usb_interface *intf,
 984                     const struct usb_device_id *udev_id)
 985 {
 986         struct usb_device *udev = interface_to_usbdev(intf);
 987         struct usb_endpoint_descriptor *endpoint;
 988         struct usb_host_interface *iface_desc;
 989         struct ds_device *dev;
 990         int i, err, alt;
 991
 992         dev = kzalloc(sizeof(struct ds_device), GFP_KERNEL);
 993         if (!dev) {
 994                 pr_info("Failed to allocate new DS9490R structure.\n");
 995                 return -ENOMEM;
 996         }
 997         dev->udev = usb_get_dev(udev);
 998         if (!dev->udev) {
 999                 err = -ENOMEM;
1000                 goto err_out_free;
1001         }
1002         memset(dev->ep, 0, sizeof(dev->ep));
1003
1004         usb_set_intfdata(intf, dev);
1005
1006         err = usb_reset_configuration(dev->udev);
1007         if (err) {
1008                 dev_err(&dev->udev->dev,
1009                         "Failed to reset configuration: err=%d.\n", err);
1010                 goto err_out_clear;
1011         }
1012
1013         /* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */
1014         alt = 3;
1015         err = usb_set_interface(dev->udev,
1016                 intf->altsetting[alt].desc.bInterfaceNumber, alt);
1017         if (err) {
1018                 dev_err(&dev->udev->dev, "Failed to set alternative setting %d "
1019                         "for %d interface: err=%d.\n", alt,
1020                         intf->altsetting[alt].desc.bInterfaceNumber, err);
1021                 goto err_out_clear;
1022         }
1023
1024         iface_desc = &intf->altsetting[alt];
1025         if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
1026                 pr_info("Num endpoints=%d. It is not DS9490R.\n",
1027                         iface_desc->desc.bNumEndpoints);
1028                 err = -EINVAL;
1029                 goto err_out_clear;
1030         }
1031
1032         /*
1033          * This loop doesn'd show control 0 endpoint,
1034          * so we will fill only 1-3 endpoints entry.
1035          */
1036         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
1037                 endpoint = &iface_desc->endpoint[i].desc;
1038
1039                 dev->ep[i+1] = endpoint->bEndpointAddress;
1040 #if 0
1041                 printk("%d: addr=%x, size=%d, dir=%s, type=%x\n",
1042                         i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
1043                         (endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
1044                         endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
1045 #endif
1046         }
1047
1048         err = ds_w1_init(dev);
1049         if (err)
1050                 goto err_out_clear;
1051
1052         mutex_lock(&ds_mutex);
1053         list_add_tail(&dev->ds_entry, &ds_devices);
1054         mutex_unlock(&ds_mutex);
1055
1056         return 0;
1057
1058 err_out_clear:
1059         usb_set_intfdata(intf, NULL);
1060         usb_put_dev(dev->udev);
1061 err_out_free:
1062         kfree(dev);
1063         return err;
1064 }
1065
1066 static void ds_disconnect(struct usb_interface *intf)
1067 {
1068         struct ds_device *dev;
1069
1070         dev = usb_get_intfdata(intf);
1071         if (!dev)
1072                 return;
1073
1074         mutex_lock(&ds_mutex);
1075         list_del(&dev->ds_entry);
1076         mutex_unlock(&ds_mutex);
1077
1078         ds_w1_fini(dev);
1079
1080         usb_set_intfdata(intf, NULL);
1081
1082         usb_put_dev(dev->udev);
1083         kfree(dev);
1084 }
1085
1086 module_usb_driver(ds_driver);
1087
1088 MODULE_LICENSE("GPL");
1089 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
1090 MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)");