1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ds2490.c USB to one wire bridge 4 * 5 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kernel.h> 10 #include <linux/mod_devicetable.h> 11 #include <linux/usb.h> 12 #include <linux/slab.h> 13 14 #include <linux/w1.h> 15 16 /* USB Standard */ 17 /* USB Control request vendor type */ 18 #define VENDOR 0x40 19 20 /* COMMAND TYPE CODES */ 21 #define CONTROL_CMD 0x00 22 #define COMM_CMD 0x01 23 #define MODE_CMD 0x02 24 25 /* CONTROL COMMAND CODES */ 26 #define CTL_RESET_DEVICE 0x0000 27 #define CTL_START_EXE 0x0001 28 #define CTL_RESUME_EXE 0x0002 29 #define CTL_HALT_EXE_IDLE 0x0003 30 #define CTL_HALT_EXE_DONE 0x0004 31 #define CTL_FLUSH_COMM_CMDS 0x0007 32 #define CTL_FLUSH_RCV_BUFFER 0x0008 33 #define CTL_FLUSH_XMT_BUFFER 0x0009 34 #define CTL_GET_COMM_CMDS 0x000A 35 36 /* MODE COMMAND CODES */ 37 #define MOD_PULSE_EN 0x0000 38 #define MOD_SPEED_CHANGE_EN 0x0001 39 #define MOD_1WIRE_SPEED 0x0002 40 #define MOD_STRONG_PU_DURATION 0x0003 41 #define MOD_PULLDOWN_SLEWRATE 0x0004 42 #define MOD_PROG_PULSE_DURATION 0x0005 43 #define MOD_WRITE1_LOWTIME 0x0006 44 #define MOD_DSOW0_TREC 0x0007 45 46 /* COMMUNICATION COMMAND CODES */ 47 #define COMM_ERROR_ESCAPE 0x0601 48 #define COMM_SET_DURATION 0x0012 49 #define COMM_BIT_IO 0x0020 50 #define COMM_PULSE 0x0030 51 #define COMM_1_WIRE_RESET 0x0042 52 #define COMM_BYTE_IO 0x0052 53 #define COMM_MATCH_ACCESS 0x0064 54 #define COMM_BLOCK_IO 0x0074 55 #define COMM_READ_STRAIGHT 0x0080 56 #define COMM_DO_RELEASE 0x6092 57 #define COMM_SET_PATH 0x00A2 58 #define COMM_WRITE_SRAM_PAGE 0x00B2 59 #define COMM_WRITE_EPROM 0x00C4 60 #define COMM_READ_CRC_PROT_PAGE 0x00D4 61 #define COMM_READ_REDIRECT_PAGE_CRC 0x21E4 62 #define COMM_SEARCH_ACCESS 0x00F4 63 64 /* Communication command bits */ 65 #define COMM_TYPE 0x0008 66 #define COMM_SE 0x0008 67 #define COMM_D 0x0008 68 #define COMM_Z 0x0008 69 #define COMM_CH 0x0008 70 #define COMM_SM 0x0008 71 #define COMM_R 0x0008 72 #define COMM_IM 0x0001 73 74 #define COMM_PS 0x4000 75 #define COMM_PST 0x4000 76 #define COMM_CIB 0x4000 77 #define COMM_RTS 0x4000 78 #define COMM_DT 0x2000 79 #define COMM_SPU 0x1000 80 #define COMM_F 0x0800 81 #define COMM_NTF 0x0400 82 #define COMM_ICP 0x0200 83 #define COMM_RST 0x0100 84 85 #define PULSE_PROG 0x01 86 #define PULSE_SPUE 0x02 87 88 #define BRANCH_MAIN 0xCC 89 #define BRANCH_AUX 0x33 90 91 /* Status flags */ 92 #define ST_SPUA 0x01 /* Strong Pull-up is active */ 93 #define ST_PRGA 0x02 /* 12V programming pulse is being generated */ 94 #define ST_12VP 0x04 /* external 12V programming voltage is present */ 95 #define ST_PMOD 0x08 /* DS2490 powered from USB and external sources */ 96 #define ST_HALT 0x10 /* DS2490 is currently halted */ 97 #define ST_IDLE 0x20 /* DS2490 is currently idle */ 98 #define ST_EPOF 0x80 99 /* Status transfer size, 16 bytes status, 16 byte result flags */ 100 #define ST_SIZE 0x20 101 102 /* Result Register flags */ 103 #define RR_DETECT 0xA5 /* New device detected */ 104 #define RR_NRS 0x01 /* Reset no presence or ... */ 105 #define RR_SH 0x02 /* short on reset or set path */ 106 #define RR_APP 0x04 /* alarming presence on reset */ 107 #define RR_VPP 0x08 /* 12V expected not seen */ 108 #define RR_CMP 0x10 /* compare error */ 109 #define RR_CRC 0x20 /* CRC error detected */ 110 #define RR_RDP 0x40 /* redirected page */ 111 #define RR_EOS 0x80 /* end of search error */ 112 113 #define SPEED_NORMAL 0x00 114 #define SPEED_FLEXIBLE 0x01 115 #define SPEED_OVERDRIVE 0x02 116 117 #define NUM_EP 4 118 #define EP_CONTROL 0 119 #define EP_STATUS 1 120 #define EP_DATA_OUT 2 121 #define EP_DATA_IN 3 122 123 struct ds_device { 124 struct list_head ds_entry; 125 126 struct usb_device *udev; 127 struct usb_interface *intf; 128 129 int ep[NUM_EP]; 130 131 /* Strong PullUp 132 * 0: pullup not active, else duration in milliseconds 133 */ 134 int spu_sleep; 135 /* spu_bit contains COMM_SPU or 0 depending on if the strong pullup 136 * should be active or not for writes. 137 */ 138 u16 spu_bit; 139 140 u8 st_buf[ST_SIZE]; 141 u8 byte_buf; 142 143 struct w1_bus_master master; 144 }; 145 146 struct ds_status { 147 u8 enable; 148 u8 speed; 149 u8 pullup_dur; 150 u8 ppuls_dur; 151 u8 pulldown_slew; 152 u8 write1_time; 153 u8 write0_time; 154 u8 reserved0; 155 u8 status; 156 u8 command0; 157 u8 command1; 158 u8 command_buffer_status; 159 u8 data_out_buffer_status; 160 u8 data_in_buffer_status; 161 u8 reserved1; 162 u8 reserved2; 163 }; 164 165 static LIST_HEAD(ds_devices); 166 static DEFINE_MUTEX(ds_mutex); 167 168 static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index) 169 { 170 int err; 171 172 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), 173 CONTROL_CMD, VENDOR, value, index, NULL, 0, 1000); 174 if (err < 0) { 175 pr_err("Failed to send command control message %x.%x: err=%d.\n", 176 value, index, err); 177 return err; 178 } 179 180 return err; 181 } 182 183 static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index) 184 { 185 int err; 186 187 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), 188 MODE_CMD, VENDOR, value, index, NULL, 0, 1000); 189 if (err < 0) { 190 pr_err("Failed to send mode control message %x.%x: err=%d.\n", 191 value, index, err); 192 return err; 193 } 194 195 return err; 196 } 197 198 static int ds_send_control(struct ds_device *dev, u16 value, u16 index) 199 { 200 int err; 201 202 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), 203 COMM_CMD, VENDOR, value, index, NULL, 0, 1000); 204 if (err < 0) { 205 pr_err("Failed to send control message %x.%x: err=%d.\n", 206 value, index, err); 207 return err; 208 } 209 210 return err; 211 } 212 213 static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off) 214 { 215 pr_info("%45s: %8x\n", str, buf[off]); 216 } 217 218 static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count) 219 { 220 int i; 221 222 pr_info("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count); 223 for (i = 0; i < count; ++i) 224 pr_info("%02x ", buf[i]); 225 pr_info("\n"); 226 227 if (count >= 16) { 228 ds_print_msg(buf, "enable flag", 0); 229 ds_print_msg(buf, "1-wire speed", 1); 230 ds_print_msg(buf, "strong pullup duration", 2); 231 ds_print_msg(buf, "programming pulse duration", 3); 232 ds_print_msg(buf, "pulldown slew rate control", 4); 233 ds_print_msg(buf, "write-1 low time", 5); 234 ds_print_msg(buf, "data sample offset/write-0 recovery time", 235 6); 236 ds_print_msg(buf, "reserved (test register)", 7); 237 ds_print_msg(buf, "device status flags", 8); 238 ds_print_msg(buf, "communication command byte 1", 9); 239 ds_print_msg(buf, "communication command byte 2", 10); 240 ds_print_msg(buf, "communication command buffer status", 11); 241 ds_print_msg(buf, "1-wire data output buffer status", 12); 242 ds_print_msg(buf, "1-wire data input buffer status", 13); 243 ds_print_msg(buf, "reserved", 14); 244 ds_print_msg(buf, "reserved", 15); 245 } 246 for (i = 16; i < count; ++i) { 247 if (buf[i] == RR_DETECT) { 248 ds_print_msg(buf, "new device detect", i); 249 continue; 250 } 251 ds_print_msg(buf, "Result Register Value: ", i); 252 if (buf[i] & RR_NRS) 253 pr_info("NRS: Reset no presence or ...\n"); 254 if (buf[i] & RR_SH) 255 pr_info("SH: short on reset or set path\n"); 256 if (buf[i] & RR_APP) 257 pr_info("APP: alarming presence on reset\n"); 258 if (buf[i] & RR_VPP) 259 pr_info("VPP: 12V expected not seen\n"); 260 if (buf[i] & RR_CMP) 261 pr_info("CMP: compare error\n"); 262 if (buf[i] & RR_CRC) 263 pr_info("CRC: CRC error detected\n"); 264 if (buf[i] & RR_RDP) 265 pr_info("RDP: redirected page\n"); 266 if (buf[i] & RR_EOS) 267 pr_info("EOS: end of search error\n"); 268 } 269 } 270 271 static int ds_recv_status(struct ds_device *dev, struct ds_status *st, 272 bool dump) 273 { 274 int count, err; 275 276 if (st) 277 memset(st, 0, sizeof(*st)); 278 279 count = 0; 280 err = usb_interrupt_msg(dev->udev, 281 usb_rcvintpipe(dev->udev, 282 dev->ep[EP_STATUS]), 283 dev->st_buf, sizeof(dev->st_buf), 284 &count, 1000); 285 if (err < 0) { 286 pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n", 287 dev->ep[EP_STATUS], err); 288 return err; 289 } 290 291 if (dump) 292 ds_dump_status(dev, dev->st_buf, count); 293 294 if (st && count >= sizeof(*st)) 295 memcpy(st, dev->st_buf, sizeof(*st)); 296 297 return count; 298 } 299 300 static void ds_reset_device(struct ds_device *dev) 301 { 302 ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0); 303 /* Always allow strong pullup which allow individual writes to use 304 * the strong pullup. 305 */ 306 if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE)) 307 pr_err("ds_reset_device: Error allowing strong pullup\n"); 308 /* Chip strong pullup time was cleared. */ 309 if (dev->spu_sleep) { 310 /* lower 4 bits are 0, see ds_set_pullup */ 311 u8 del = dev->spu_sleep>>4; 312 if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del)) 313 pr_err("ds_reset_device: Error setting duration\n"); 314 } 315 } 316 317 static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size) 318 { 319 int count, err; 320 321 /* Careful on size. If size is less than what is available in 322 * the input buffer, the device fails the bulk transfer and 323 * clears the input buffer. It could read the maximum size of 324 * the data buffer, but then do you return the first, last, or 325 * some set of the middle size bytes? As long as the rest of 326 * the code is correct there will be size bytes waiting. A 327 * call to ds_wait_status will wait until the device is idle 328 * and any data to be received would have been available. 329 */ 330 count = 0; 331 err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]), 332 buf, size, &count, 1000); 333 if (err < 0) { 334 pr_info("Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]); 335 usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN])); 336 ds_recv_status(dev, NULL, true); 337 return err; 338 } 339 340 #if 0 341 { 342 int i; 343 344 printk("%s: count=%d: ", __func__, count); 345 for (i = 0; i < count; ++i) 346 printk("%02x ", buf[i]); 347 printk("\n"); 348 } 349 #endif 350 return count; 351 } 352 353 static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len) 354 { 355 int count, err; 356 357 count = 0; 358 err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000); 359 if (err < 0) { 360 pr_err("Failed to write 1-wire data to ep0x%x: " 361 "err=%d.\n", dev->ep[EP_DATA_OUT], err); 362 return err; 363 } 364 365 return err; 366 } 367 368 #if 0 369 370 int ds_stop_pulse(struct ds_device *dev, int limit) 371 { 372 struct ds_status st; 373 int count = 0, err = 0; 374 375 do { 376 err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0); 377 if (err) 378 break; 379 err = ds_send_control(dev, CTL_RESUME_EXE, 0); 380 if (err) 381 break; 382 err = ds_recv_status(dev, &st, false); 383 if (err) 384 break; 385 386 if ((st.status & ST_SPUA) == 0) { 387 err = ds_send_control_mode(dev, MOD_PULSE_EN, 0); 388 if (err) 389 break; 390 } 391 } while (++count < limit); 392 393 return err; 394 } 395 396 int ds_detect(struct ds_device *dev, struct ds_status *st) 397 { 398 int err; 399 400 err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0); 401 if (err) 402 return err; 403 404 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0); 405 if (err) 406 return err; 407 408 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40); 409 if (err) 410 return err; 411 412 err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG); 413 if (err) 414 return err; 415 416 err = ds_dump_status(dev, st); 417 418 return err; 419 } 420 421 #endif /* 0 */ 422 423 static int ds_wait_status(struct ds_device *dev, struct ds_status *st) 424 { 425 int err, count = 0; 426 427 do { 428 st->status = 0; 429 err = ds_recv_status(dev, st, false); 430 #if 0 431 if (err >= 0) { 432 int i; 433 printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err); 434 for (i = 0; i < err; ++i) 435 printk("%02x ", dev->st_buf[i]); 436 printk("\n"); 437 } 438 #endif 439 } while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100); 440 441 if (err >= 16 && st->status & ST_EPOF) { 442 pr_info("Resetting device after ST_EPOF.\n"); 443 ds_reset_device(dev); 444 /* Always dump the device status. */ 445 count = 101; 446 } 447 448 /* Dump the status for errors or if there is extended return data. 449 * The extended status includes new device detection (maybe someone 450 * can do something with it). 451 */ 452 if (err > 16 || count >= 100 || err < 0) 453 ds_dump_status(dev, dev->st_buf, err); 454 455 /* Extended data isn't an error. Well, a short is, but the dump 456 * would have already told the user that and we can't do anything 457 * about it in software anyway. 458 */ 459 if (count >= 100 || err < 0) 460 return -1; 461 else 462 return 0; 463 } 464 465 static int ds_reset(struct ds_device *dev) 466 { 467 int err; 468 469 /* Other potentionally interesting flags for reset. 470 * 471 * COMM_NTF: Return result register feedback. This could be used to 472 * detect some conditions such as short, alarming presence, or 473 * detect if a new device was detected. 474 * 475 * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE: 476 * Select the data transfer rate. 477 */ 478 err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL); 479 if (err) 480 return err; 481 482 return 0; 483 } 484 485 #if 0 486 static int ds_set_speed(struct ds_device *dev, int speed) 487 { 488 int err; 489 490 if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE) 491 return -EINVAL; 492 493 if (speed != SPEED_OVERDRIVE) 494 speed = SPEED_FLEXIBLE; 495 496 speed &= 0xff; 497 498 err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed); 499 if (err) 500 return err; 501 502 return err; 503 } 504 #endif /* 0 */ 505 506 static int ds_set_pullup(struct ds_device *dev, int delay) 507 { 508 int err = 0; 509 u8 del = 1 + (u8)(delay >> 4); 510 /* Just storing delay would not get the trunication and roundup. */ 511 int ms = del<<4; 512 513 /* Enable spu_bit if a delay is set. */ 514 dev->spu_bit = delay ? COMM_SPU : 0; 515 /* If delay is zero, it has already been disabled, if the time is 516 * the same as the hardware was last programmed to, there is also 517 * nothing more to do. Compare with the recalculated value ms 518 * rather than del or delay which can have a different value. 519 */ 520 if (delay == 0 || ms == dev->spu_sleep) 521 return err; 522 523 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del); 524 if (err) 525 return err; 526 527 dev->spu_sleep = ms; 528 529 return err; 530 } 531 532 static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit) 533 { 534 int err; 535 struct ds_status st; 536 537 err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0), 538 0); 539 if (err) 540 return err; 541 542 ds_wait_status(dev, &st); 543 544 err = ds_recv_data(dev, tbit, sizeof(*tbit)); 545 if (err < 0) 546 return err; 547 548 return 0; 549 } 550 551 #if 0 552 static int ds_write_bit(struct ds_device *dev, u8 bit) 553 { 554 int err; 555 struct ds_status st; 556 557 /* Set COMM_ICP to write without a readback. Note, this will 558 * produce one time slot, a down followed by an up with COMM_D 559 * only determing the timing. 560 */ 561 err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP | 562 (bit ? COMM_D : 0), 0); 563 if (err) 564 return err; 565 566 ds_wait_status(dev, &st); 567 568 return 0; 569 } 570 #endif 571 572 static int ds_write_byte(struct ds_device *dev, u8 byte) 573 { 574 int err; 575 struct ds_status st; 576 577 err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, byte); 578 if (err) 579 return err; 580 581 if (dev->spu_bit) 582 msleep(dev->spu_sleep); 583 584 err = ds_wait_status(dev, &st); 585 if (err) 586 return err; 587 588 err = ds_recv_data(dev, &dev->byte_buf, 1); 589 if (err < 0) 590 return err; 591 592 return !(byte == dev->byte_buf); 593 } 594 595 static int ds_read_byte(struct ds_device *dev, u8 *byte) 596 { 597 int err; 598 struct ds_status st; 599 600 err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM, 0xff); 601 if (err) 602 return err; 603 604 ds_wait_status(dev, &st); 605 606 err = ds_recv_data(dev, byte, sizeof(*byte)); 607 if (err < 0) 608 return err; 609 610 return 0; 611 } 612 613 static int ds_read_block(struct ds_device *dev, u8 *buf, int len) 614 { 615 struct ds_status st; 616 int err; 617 618 if (len > 64*1024) 619 return -E2BIG; 620 621 memset(buf, 0xFF, len); 622 623 err = ds_send_data(dev, buf, len); 624 if (err < 0) 625 return err; 626 627 err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, len); 628 if (err) 629 return err; 630 631 ds_wait_status(dev, &st); 632 633 memset(buf, 0x00, len); 634 err = ds_recv_data(dev, buf, len); 635 636 return err; 637 } 638 639 static int ds_write_block(struct ds_device *dev, u8 *buf, int len) 640 { 641 int err; 642 struct ds_status st; 643 644 err = ds_send_data(dev, buf, len); 645 if (err < 0) 646 return err; 647 648 err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, len); 649 if (err) 650 return err; 651 652 if (dev->spu_bit) 653 msleep(dev->spu_sleep); 654 655 ds_wait_status(dev, &st); 656 657 err = ds_recv_data(dev, buf, len); 658 if (err < 0) 659 return err; 660 661 return !(err == len); 662 } 663 664 static void ds9490r_search(void *data, struct w1_master *master, 665 u8 search_type, w1_slave_found_callback callback) 666 { 667 /* When starting with an existing id, the first id returned will 668 * be that device (if it is still on the bus most likely). 669 * 670 * If the number of devices found is less than or equal to the 671 * search_limit, that number of IDs will be returned. If there are 672 * more, search_limit IDs will be returned followed by a non-zero 673 * discrepency value. 674 */ 675 struct ds_device *dev = data; 676 int err; 677 u16 value, index; 678 struct ds_status st; 679 int search_limit; 680 int found = 0; 681 int i; 682 683 /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for 684 * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time. 685 */ 686 const unsigned long jtime = msecs_to_jiffies(1000*8/75); 687 /* FIFO 128 bytes, bulk packet size 64, read a multiple of the 688 * packet size. 689 */ 690 const size_t bufsize = 2 * 64; 691 u64 *buf, *found_ids; 692 693 buf = kmalloc(bufsize, GFP_KERNEL); 694 if (!buf) 695 return; 696 697 /* 698 * We are holding the bus mutex during the scan, but adding devices via the 699 * callback needs the bus to be unlocked. So we queue up found ids here. 700 */ 701 found_ids = kmalloc_array(master->max_slave_count, sizeof(u64), GFP_KERNEL); 702 if (!found_ids) { 703 kfree(buf); 704 return; 705 } 706 707 mutex_lock(&master->bus_mutex); 708 709 /* address to start searching at */ 710 if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0) 711 goto search_out; 712 master->search_id = 0; 713 714 value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F | 715 COMM_RTS; 716 search_limit = master->max_slave_count; 717 if (search_limit > 255) 718 search_limit = 0; 719 index = search_type | (search_limit << 8); 720 if (ds_send_control(dev, value, index) < 0) 721 goto search_out; 722 723 do { 724 schedule_timeout(jtime); 725 726 err = ds_recv_status(dev, &st, false); 727 if (err < 0 || err < sizeof(st)) 728 break; 729 730 if (st.data_in_buffer_status) { 731 /* Bulk in can receive partial ids, but when it does 732 * they fail crc and will be discarded anyway. 733 * That has only been seen when status in buffer 734 * is 0 and bulk is read anyway, so don't read 735 * bulk without first checking if status says there 736 * is data to read. 737 */ 738 err = ds_recv_data(dev, (u8 *)buf, bufsize); 739 if (err < 0) 740 break; 741 for (i = 0; i < err/8; ++i) { 742 found_ids[found++] = buf[i]; 743 /* can't know if there will be a discrepancy 744 * value after until the next id */ 745 if (found == search_limit) { 746 master->search_id = buf[i]; 747 break; 748 } 749 } 750 } 751 752 if (test_bit(W1_ABORT_SEARCH, &master->flags)) 753 break; 754 } while (!(st.status & (ST_IDLE | ST_HALT))); 755 756 /* only continue the search if some weren't found */ 757 if (found <= search_limit) { 758 master->search_id = 0; 759 } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) { 760 /* Only max_slave_count will be scanned in a search, 761 * but it will start where it left off next search 762 * until all ids are identified and then it will start 763 * over. A continued search will report the previous 764 * last id as the first id (provided it is still on the 765 * bus). 766 */ 767 dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, " 768 "will continue next search.\n", __func__, 769 master->max_slave_count); 770 set_bit(W1_WARN_MAX_COUNT, &master->flags); 771 } 772 773 search_out: 774 mutex_unlock(&master->bus_mutex); 775 kfree(buf); 776 777 for (i = 0; i < found; i++) /* run callback for all queued up IDs */ 778 callback(master, found_ids[i]); 779 kfree(found_ids); 780 } 781 782 #if 0 783 /* 784 * FIXME: if this disabled code is ever used in the future all ds_send_data() 785 * calls must be changed to use a DMAable buffer. 786 */ 787 static int ds_match_access(struct ds_device *dev, u64 init) 788 { 789 int err; 790 struct ds_status st; 791 792 err = ds_send_data(dev, (unsigned char *)&init, sizeof(init)); 793 if (err) 794 return err; 795 796 ds_wait_status(dev, &st); 797 798 err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055); 799 if (err) 800 return err; 801 802 ds_wait_status(dev, &st); 803 804 return 0; 805 } 806 807 static int ds_set_path(struct ds_device *dev, u64 init) 808 { 809 int err; 810 struct ds_status st; 811 u8 buf[9]; 812 813 memcpy(buf, &init, 8); 814 buf[8] = BRANCH_MAIN; 815 816 err = ds_send_data(dev, buf, sizeof(buf)); 817 if (err) 818 return err; 819 820 ds_wait_status(dev, &st); 821 822 err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0); 823 if (err) 824 return err; 825 826 ds_wait_status(dev, &st); 827 828 return 0; 829 } 830 831 #endif /* 0 */ 832 833 static u8 ds9490r_touch_bit(void *data, u8 bit) 834 { 835 struct ds_device *dev = data; 836 837 if (ds_touch_bit(dev, bit, &dev->byte_buf)) 838 return 0; 839 840 return dev->byte_buf; 841 } 842 843 #if 0 844 static void ds9490r_write_bit(void *data, u8 bit) 845 { 846 struct ds_device *dev = data; 847 848 ds_write_bit(dev, bit); 849 } 850 851 static u8 ds9490r_read_bit(void *data) 852 { 853 struct ds_device *dev = data; 854 int err; 855 856 err = ds_touch_bit(dev, 1, &dev->byte_buf); 857 if (err) 858 return 0; 859 860 return dev->byte_buf & 1; 861 } 862 #endif 863 864 static void ds9490r_write_byte(void *data, u8 byte) 865 { 866 struct ds_device *dev = data; 867 868 ds_write_byte(dev, byte); 869 } 870 871 static u8 ds9490r_read_byte(void *data) 872 { 873 struct ds_device *dev = data; 874 int err; 875 876 err = ds_read_byte(dev, &dev->byte_buf); 877 if (err) 878 return 0; 879 880 return dev->byte_buf; 881 } 882 883 static void ds9490r_write_block(void *data, const u8 *buf, int len) 884 { 885 struct ds_device *dev = data; 886 u8 *tbuf; 887 888 if (len <= 0) 889 return; 890 891 tbuf = kmemdup(buf, len, GFP_KERNEL); 892 if (!tbuf) 893 return; 894 895 ds_write_block(dev, tbuf, len); 896 897 kfree(tbuf); 898 } 899 900 static u8 ds9490r_read_block(void *data, u8 *buf, int len) 901 { 902 struct ds_device *dev = data; 903 int err; 904 u8 *tbuf; 905 906 if (len <= 0) 907 return 0; 908 909 tbuf = kmalloc(len, GFP_KERNEL); 910 if (!tbuf) 911 return 0; 912 913 err = ds_read_block(dev, tbuf, len); 914 if (err >= 0) 915 memcpy(buf, tbuf, len); 916 917 kfree(tbuf); 918 919 return err >= 0 ? len : 0; 920 } 921 922 static u8 ds9490r_reset(void *data) 923 { 924 struct ds_device *dev = data; 925 int err; 926 927 err = ds_reset(dev); 928 if (err) 929 return 1; 930 931 return 0; 932 } 933 934 static u8 ds9490r_set_pullup(void *data, int delay) 935 { 936 struct ds_device *dev = data; 937 938 if (ds_set_pullup(dev, delay)) 939 return 1; 940 941 return 0; 942 } 943 944 static int ds_w1_init(struct ds_device *dev) 945 { 946 memset(&dev->master, 0, sizeof(struct w1_bus_master)); 947 948 /* Reset the device as it can be in a bad state. 949 * This is necessary because a block write will wait for data 950 * to be placed in the output buffer and block any later 951 * commands which will keep accumulating and the device will 952 * not be idle. Another case is removing the ds2490 module 953 * while a bus search is in progress, somehow a few commands 954 * get through, but the input transfers fail leaving data in 955 * the input buffer. This will cause the next read to fail 956 * see the note in ds_recv_data. 957 */ 958 ds_reset_device(dev); 959 960 dev->master.data = dev; 961 dev->master.touch_bit = &ds9490r_touch_bit; 962 /* read_bit and write_bit in w1_bus_master are expected to set and 963 * sample the line level. For write_bit that means it is expected to 964 * set it to that value and leave it there. ds2490 only supports an 965 * individual time slot at the lowest level. The requirement from 966 * pulling the bus state down to reading the state is 15us, something 967 * that isn't realistic on the USB bus anyway. 968 dev->master.read_bit = &ds9490r_read_bit; 969 dev->master.write_bit = &ds9490r_write_bit; 970 */ 971 dev->master.read_byte = &ds9490r_read_byte; 972 dev->master.write_byte = &ds9490r_write_byte; 973 dev->master.read_block = &ds9490r_read_block; 974 dev->master.write_block = &ds9490r_write_block; 975 dev->master.reset_bus = &ds9490r_reset; 976 dev->master.set_pullup = &ds9490r_set_pullup; 977 dev->master.search = &ds9490r_search; 978 979 return w1_add_master_device(&dev->master); 980 } 981 982 static void ds_w1_fini(struct ds_device *dev) 983 { 984 w1_remove_master_device(&dev->master); 985 } 986 987 static int ds_probe(struct usb_interface *intf, 988 const struct usb_device_id *udev_id) 989 { 990 struct usb_device *udev = interface_to_usbdev(intf); 991 struct usb_endpoint_descriptor *endpoint; 992 struct usb_host_interface *iface_desc; 993 struct ds_device *dev; 994 int i, err, alt; 995 996 dev = kzalloc(sizeof(struct ds_device), GFP_KERNEL); 997 if (!dev) { 998 pr_info("Failed to allocate new DS9490R structure.\n"); 999 return -ENOMEM; 1000 } 1001 dev->udev = usb_get_dev(udev); 1002 if (!dev->udev) { 1003 err = -ENOMEM; 1004 goto err_out_free; 1005 } 1006 memset(dev->ep, 0, sizeof(dev->ep)); 1007 1008 usb_set_intfdata(intf, dev); 1009 1010 err = usb_reset_configuration(dev->udev); 1011 if (err) { 1012 dev_err(&dev->udev->dev, 1013 "Failed to reset configuration: err=%d.\n", err); 1014 goto err_out_clear; 1015 } 1016 1017 /* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */ 1018 alt = 3; 1019 err = usb_set_interface(dev->udev, 1020 intf->cur_altsetting->desc.bInterfaceNumber, alt); 1021 if (err) { 1022 dev_err(&dev->udev->dev, "Failed to set alternative setting %d " 1023 "for %d interface: err=%d.\n", alt, 1024 intf->cur_altsetting->desc.bInterfaceNumber, err); 1025 goto err_out_clear; 1026 } 1027 1028 iface_desc = intf->cur_altsetting; 1029 if (iface_desc->desc.bNumEndpoints != NUM_EP-1) { 1030 pr_info("Num endpoints=%d. It is not DS9490R.\n", 1031 iface_desc->desc.bNumEndpoints); 1032 err = -EINVAL; 1033 goto err_out_clear; 1034 } 1035 1036 /* 1037 * This loop doesn'd show control 0 endpoint, 1038 * so we will fill only 1-3 endpoints entry. 1039 */ 1040 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { 1041 endpoint = &iface_desc->endpoint[i].desc; 1042 1043 dev->ep[i+1] = endpoint->bEndpointAddress; 1044 #if 0 1045 printk("%d: addr=%x, size=%d, dir=%s, type=%x\n", 1046 i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize), 1047 (endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT", 1048 endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK); 1049 #endif 1050 } 1051 1052 err = ds_w1_init(dev); 1053 if (err) 1054 goto err_out_clear; 1055 1056 mutex_lock(&ds_mutex); 1057 list_add_tail(&dev->ds_entry, &ds_devices); 1058 mutex_unlock(&ds_mutex); 1059 1060 return 0; 1061 1062 err_out_clear: 1063 usb_set_intfdata(intf, NULL); 1064 usb_put_dev(dev->udev); 1065 err_out_free: 1066 kfree(dev); 1067 return err; 1068 } 1069 1070 static void ds_disconnect(struct usb_interface *intf) 1071 { 1072 struct ds_device *dev; 1073 1074 dev = usb_get_intfdata(intf); 1075 if (!dev) 1076 return; 1077 1078 mutex_lock(&ds_mutex); 1079 list_del(&dev->ds_entry); 1080 mutex_unlock(&ds_mutex); 1081 1082 ds_w1_fini(dev); 1083 1084 usb_set_intfdata(intf, NULL); 1085 1086 usb_put_dev(dev->udev); 1087 kfree(dev); 1088 } 1089 1090 static const struct usb_device_id ds_id_table[] = { 1091 { USB_DEVICE(0x04fa, 0x2490) }, 1092 { }, 1093 }; 1094 MODULE_DEVICE_TABLE(usb, ds_id_table); 1095 1096 static struct usb_driver ds_driver = { 1097 .name = "DS9490R", 1098 .probe = ds_probe, 1099 .disconnect = ds_disconnect, 1100 .id_table = ds_id_table, 1101 }; 1102 module_usb_driver(ds_driver); 1103 1104 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); 1105 MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)"); 1106 MODULE_LICENSE("GPL"); 1107