1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * w1_therm.c 4 * 5 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> 6 */ 7 8 #include <asm/types.h> 9 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/moduleparam.h> 13 #include <linux/sched.h> 14 #include <linux/device.h> 15 #include <linux/types.h> 16 #include <linux/slab.h> 17 #include <linux/delay.h> 18 #include <linux/hwmon.h> 19 #include <linux/string.h> 20 #include <linux/jiffies.h> 21 22 #include <linux/w1.h> 23 24 #define W1_THERM_DS18S20 0x10 25 #define W1_THERM_DS1822 0x22 26 #define W1_THERM_DS18B20 0x28 27 #define W1_THERM_DS1825 0x3B 28 #define W1_THERM_DS28EA00 0x42 29 30 /* 31 * Allow the strong pullup to be disabled, but default to enabled. 32 * If it was disabled a parasite powered device might not get the require 33 * current to do a temperature conversion. If it is enabled parasite powered 34 * devices have a better chance of getting the current required. 35 * In case the parasite power-detection is not working (seems to be the case 36 * for some DS18S20) the strong pullup can also be forced, regardless of the 37 * power state of the devices. 38 * 39 * Summary of options: 40 * - strong_pullup = 0 Disable strong pullup completely 41 * - strong_pullup = 1 Enable automatic strong pullup detection 42 * - strong_pullup = 2 Force strong pullup 43 */ 44 static int w1_strong_pullup = 1; 45 module_param_named(strong_pullup, w1_strong_pullup, int, 0); 46 47 /* Counter for devices supporting bulk reading */ 48 static u16 bulk_read_device_counter; /* =0 as per C standard */ 49 50 /* This command should be in public header w1.h but is not */ 51 #define W1_RECALL_EEPROM 0xB8 52 53 /* Nb of try for an operation */ 54 #define W1_THERM_MAX_TRY 5 55 56 /* ms delay to retry bus mutex */ 57 #define W1_THERM_RETRY_DELAY 20 58 59 /* delay in ms to write in EEPROM */ 60 #define W1_THERM_EEPROM_WRITE_DELAY 10 61 62 #define EEPROM_CMD_WRITE "save" /* cmd for write eeprom sysfs */ 63 #define EEPROM_CMD_READ "restore" /* cmd for read eeprom sysfs */ 64 #define BULK_TRIGGER_CMD "trigger" /* cmd to trigger a bulk read */ 65 66 #define MIN_TEMP -55 /* min temperature that can be measured */ 67 #define MAX_TEMP 125 /* max temperature that can be measured */ 68 69 /* Allowed values for sysfs conv_time attribute */ 70 #define CONV_TIME_DEFAULT 0 71 #define CONV_TIME_MEASURE 1 72 73 /* Bits in sysfs "features" value */ 74 #define W1_THERM_CHECK_RESULT 1 /* Enable conversion success check */ 75 #define W1_THERM_POLL_COMPLETION 2 /* Poll for conversion completion */ 76 #define W1_THERM_FEATURES_MASK 3 /* All values mask */ 77 78 /* Poll period in milliseconds. Should be less then a shortest operation on the device */ 79 #define W1_POLL_PERIOD 32 80 #define W1_POLL_CONVERT_TEMP 2000 /* Timeout for W1_CONVERT_TEMP, ms */ 81 #define W1_POLL_RECALL_EEPROM 500 /* Timeout for W1_RECALL_EEPROM, ms*/ 82 83 /* Masks for resolution functions, work with all devices */ 84 /* Bit mask for config register for all devices, bits 7,6,5 */ 85 #define W1_THERM_RESOLUTION_MASK 0xE0 86 /* Bit offset of resolution in config register for all devices */ 87 #define W1_THERM_RESOLUTION_SHIFT 5 88 /* Bit offset of resolution in config register for all devices */ 89 #define W1_THERM_RESOLUTION_SHIFT 5 90 /* Add this to bit value to get resolution */ 91 #define W1_THERM_RESOLUTION_MIN 9 92 /* Maximum allowed value */ 93 #define W1_THERM_RESOLUTION_MAX 14 94 95 /* Helpers Macros */ 96 97 /* 98 * return a pointer on the slave w1_therm_family_converter struct: 99 * always test family data existence before using this macro 100 */ 101 #define SLAVE_SPECIFIC_FUNC(sl) \ 102 (((struct w1_therm_family_data *)(sl->family_data))->specific_functions) 103 104 /* 105 * return the power mode of the sl slave : 1-ext, 0-parasite, <0 unknown 106 * always test family data existence before using this macro 107 */ 108 #define SLAVE_POWERMODE(sl) \ 109 (((struct w1_therm_family_data *)(sl->family_data))->external_powered) 110 111 /* 112 * return the resolution in bit of the sl slave : <0 unknown 113 * always test family data existence before using this macro 114 */ 115 #define SLAVE_RESOLUTION(sl) \ 116 (((struct w1_therm_family_data *)(sl->family_data))->resolution) 117 118 /* 119 * return the conv_time_override of the sl slave 120 * always test family data existence before using this macro 121 */ 122 #define SLAVE_CONV_TIME_OVERRIDE(sl) \ 123 (((struct w1_therm_family_data *)(sl->family_data))->conv_time_override) 124 125 /* 126 * return the features of the sl slave 127 * always test family data existence before using this macro 128 */ 129 #define SLAVE_FEATURES(sl) \ 130 (((struct w1_therm_family_data *)(sl->family_data))->features) 131 132 /* 133 * return whether or not a converT command has been issued to the slave 134 * * 0: no bulk read is pending 135 * * -1: conversion is in progress 136 * * 1: conversion done, result to be read 137 */ 138 #define SLAVE_CONVERT_TRIGGERED(sl) \ 139 (((struct w1_therm_family_data *)(sl->family_data))->convert_triggered) 140 141 /* return the address of the refcnt in the family data */ 142 #define THERM_REFCNT(family_data) \ 143 (&((struct w1_therm_family_data *)family_data)->refcnt) 144 145 /* Structs definition */ 146 147 /** 148 * struct w1_therm_family_converter - bind device specific functions 149 * @broken: flag for non-registred families 150 * @reserved: not used here 151 * @f: pointer to the device binding structure 152 * @convert: pointer to the device conversion function 153 * @get_conversion_time: pointer to the device conversion time function 154 * @set_resolution: pointer to the device set_resolution function 155 * @get_resolution: pointer to the device get_resolution function 156 * @write_data: pointer to the device writing function (2 or 3 bytes) 157 * @bulk_read: true if device family support bulk read, false otherwise 158 */ 159 struct w1_therm_family_converter { 160 u8 broken; 161 u16 reserved; 162 struct w1_family *f; 163 int (*convert)(u8 rom[9]); 164 int (*get_conversion_time)(struct w1_slave *sl); 165 int (*set_resolution)(struct w1_slave *sl, int val); 166 int (*get_resolution)(struct w1_slave *sl); 167 int (*write_data)(struct w1_slave *sl, const u8 *data); 168 bool bulk_read; 169 }; 170 171 /** 172 * struct w1_therm_family_data - device data 173 * @rom: ROM device id (64bit Lasered ROM code + 1 CRC byte) 174 * @refcnt: ref count 175 * @external_powered: 1 device powered externally, 176 * 0 device parasite powered, 177 * -x error or undefined 178 * @resolution: current device resolution 179 * @convert_triggered: conversion state of the device 180 * @conv_time_override: user selected conversion time or CONV_TIME_DEFAULT 181 * @features: bit mask - enable temperature validity check, poll for completion 182 * @specific_functions: pointer to struct of device specific function 183 */ 184 struct w1_therm_family_data { 185 uint8_t rom[9]; 186 atomic_t refcnt; 187 int external_powered; 188 int resolution; 189 int convert_triggered; 190 int conv_time_override; 191 unsigned int features; 192 struct w1_therm_family_converter *specific_functions; 193 }; 194 195 /** 196 * struct therm_info - store temperature reading 197 * @rom: read device data (8 data bytes + 1 CRC byte) 198 * @crc: computed crc from rom 199 * @verdict: 1 crc checked, 0 crc not matching 200 */ 201 struct therm_info { 202 u8 rom[9]; 203 u8 crc; 204 u8 verdict; 205 }; 206 207 /* Hardware Functions declaration */ 208 209 /** 210 * reset_select_slave() - reset and select a slave 211 * @sl: the slave to select 212 * 213 * Resets the bus and select the slave by sending a ROM MATCH cmd 214 * w1_reset_select_slave() from w1_io.c could not be used here because 215 * it sent a SKIP ROM command if only one device is on the line. 216 * At the beginning of the such process, sl->master->slave_count is 1 even if 217 * more devices are on the line, causing collision on the line. 218 * 219 * Context: The w1 master lock must be held. 220 * 221 * Return: 0 if success, negative kernel error code otherwise. 222 */ 223 static int reset_select_slave(struct w1_slave *sl); 224 225 /** 226 * convert_t() - Query the device for temperature conversion and read 227 * @sl: pointer to the slave to read 228 * @info: pointer to a structure to store the read results 229 * 230 * Return: 0 if success, -kernel error code otherwise 231 */ 232 static int convert_t(struct w1_slave *sl, struct therm_info *info); 233 234 /** 235 * read_scratchpad() - read the data in device RAM 236 * @sl: pointer to the slave to read 237 * @info: pointer to a structure to store the read results 238 * 239 * Return: 0 if success, -kernel error code otherwise 240 */ 241 static int read_scratchpad(struct w1_slave *sl, struct therm_info *info); 242 243 /** 244 * write_scratchpad() - write nb_bytes in the device RAM 245 * @sl: pointer to the slave to write in 246 * @data: pointer to an array of 3 bytes, as 3 bytes MUST be written 247 * @nb_bytes: number of bytes to be written (2 for DS18S20, 3 otherwise) 248 * 249 * Return: 0 if success, -kernel error code otherwise 250 */ 251 static int write_scratchpad(struct w1_slave *sl, const u8 *data, u8 nb_bytes); 252 253 /** 254 * copy_scratchpad() - Copy the content of scratchpad in device EEPROM 255 * @sl: slave involved 256 * 257 * Return: 0 if success, -kernel error code otherwise 258 */ 259 static int copy_scratchpad(struct w1_slave *sl); 260 261 /** 262 * recall_eeprom() - Restore EEPROM data to device RAM 263 * @sl: slave involved 264 * 265 * Return: 0 if success, -kernel error code otherwise 266 */ 267 static int recall_eeprom(struct w1_slave *sl); 268 269 /** 270 * read_powermode() - Query the power mode of the slave 271 * @sl: slave to retrieve the power mode 272 * 273 * Ask the device to get its power mode (external or parasite) 274 * and store the power status in the &struct w1_therm_family_data. 275 * 276 * Return: 277 * * 0 parasite powered device 278 * * 1 externally powered device 279 * * <0 kernel error code 280 */ 281 static int read_powermode(struct w1_slave *sl); 282 283 /** 284 * trigger_bulk_read() - function to trigger a bulk read on the bus 285 * @dev_master: the device master of the bus 286 * 287 * Send a SKIP ROM follow by a CONVERT T commmand on the bus. 288 * It also set the status flag in each slave &struct w1_therm_family_data 289 * to signal that a conversion is in progress. 290 * 291 * Return: 0 if success, -kernel error code otherwise 292 */ 293 static int trigger_bulk_read(struct w1_master *dev_master); 294 295 /* Sysfs interface declaration */ 296 297 static ssize_t w1_slave_show(struct device *device, 298 struct device_attribute *attr, char *buf); 299 300 static ssize_t w1_slave_store(struct device *device, 301 struct device_attribute *attr, const char *buf, size_t size); 302 303 static ssize_t w1_seq_show(struct device *device, 304 struct device_attribute *attr, char *buf); 305 306 static ssize_t temperature_show(struct device *device, 307 struct device_attribute *attr, char *buf); 308 309 static ssize_t ext_power_show(struct device *device, 310 struct device_attribute *attr, char *buf); 311 312 static ssize_t resolution_show(struct device *device, 313 struct device_attribute *attr, char *buf); 314 315 static ssize_t resolution_store(struct device *device, 316 struct device_attribute *attr, const char *buf, size_t size); 317 318 static ssize_t eeprom_cmd_store(struct device *device, 319 struct device_attribute *attr, const char *buf, size_t size); 320 321 static ssize_t alarms_store(struct device *device, 322 struct device_attribute *attr, const char *buf, size_t size); 323 324 static ssize_t alarms_show(struct device *device, 325 struct device_attribute *attr, char *buf); 326 327 static ssize_t therm_bulk_read_store(struct device *device, 328 struct device_attribute *attr, const char *buf, size_t size); 329 330 static ssize_t therm_bulk_read_show(struct device *device, 331 struct device_attribute *attr, char *buf); 332 333 static ssize_t conv_time_show(struct device *device, 334 struct device_attribute *attr, char *buf); 335 336 static ssize_t conv_time_store(struct device *device, 337 struct device_attribute *attr, const char *buf, 338 size_t size); 339 340 static ssize_t features_show(struct device *device, 341 struct device_attribute *attr, char *buf); 342 343 static ssize_t features_store(struct device *device, 344 struct device_attribute *attr, const char *buf, 345 size_t size); 346 /* Attributes declarations */ 347 348 static DEVICE_ATTR_RW(w1_slave); 349 static DEVICE_ATTR_RO(w1_seq); 350 static DEVICE_ATTR_RO(temperature); 351 static DEVICE_ATTR_RO(ext_power); 352 static DEVICE_ATTR_RW(resolution); 353 static DEVICE_ATTR_WO(eeprom_cmd); 354 static DEVICE_ATTR_RW(alarms); 355 static DEVICE_ATTR_RW(conv_time); 356 static DEVICE_ATTR_RW(features); 357 358 static DEVICE_ATTR_RW(therm_bulk_read); /* attribut at master level */ 359 360 /* Interface Functions declaration */ 361 362 /** 363 * w1_therm_add_slave() - Called when a new slave is discovered 364 * @sl: slave just discovered by the master. 365 * 366 * Called by the master when the slave is discovered on the bus. Used to 367 * initialize slave state before the beginning of any communication. 368 * 369 * Return: 0 - If success, negative kernel code otherwise 370 */ 371 static int w1_therm_add_slave(struct w1_slave *sl); 372 373 /** 374 * w1_therm_remove_slave() - Called when a slave is removed 375 * @sl: slave to be removed. 376 * 377 * Called by the master when the slave is considered not to be on the bus 378 * anymore. Used to free memory. 379 */ 380 static void w1_therm_remove_slave(struct w1_slave *sl); 381 382 /* Family attributes */ 383 384 static struct attribute *w1_therm_attrs[] = { 385 &dev_attr_w1_slave.attr, 386 &dev_attr_temperature.attr, 387 &dev_attr_ext_power.attr, 388 &dev_attr_resolution.attr, 389 &dev_attr_eeprom_cmd.attr, 390 &dev_attr_alarms.attr, 391 &dev_attr_conv_time.attr, 392 &dev_attr_features.attr, 393 NULL, 394 }; 395 396 static struct attribute *w1_ds18s20_attrs[] = { 397 &dev_attr_w1_slave.attr, 398 &dev_attr_temperature.attr, 399 &dev_attr_ext_power.attr, 400 &dev_attr_eeprom_cmd.attr, 401 &dev_attr_alarms.attr, 402 &dev_attr_conv_time.attr, 403 &dev_attr_features.attr, 404 NULL, 405 }; 406 407 static struct attribute *w1_ds28ea00_attrs[] = { 408 &dev_attr_w1_slave.attr, 409 &dev_attr_w1_seq.attr, 410 &dev_attr_temperature.attr, 411 &dev_attr_ext_power.attr, 412 &dev_attr_resolution.attr, 413 &dev_attr_eeprom_cmd.attr, 414 &dev_attr_alarms.attr, 415 &dev_attr_conv_time.attr, 416 &dev_attr_features.attr, 417 NULL, 418 }; 419 420 /* Attribute groups */ 421 422 ATTRIBUTE_GROUPS(w1_therm); 423 ATTRIBUTE_GROUPS(w1_ds18s20); 424 ATTRIBUTE_GROUPS(w1_ds28ea00); 425 426 #if IS_REACHABLE(CONFIG_HWMON) 427 static int w1_read_temp(struct device *dev, u32 attr, int channel, 428 long *val); 429 430 static umode_t w1_is_visible(const void *_data, enum hwmon_sensor_types type, 431 u32 attr, int channel) 432 { 433 return attr == hwmon_temp_input ? 0444 : 0; 434 } 435 436 static int w1_read(struct device *dev, enum hwmon_sensor_types type, 437 u32 attr, int channel, long *val) 438 { 439 switch (type) { 440 case hwmon_temp: 441 return w1_read_temp(dev, attr, channel, val); 442 default: 443 return -EOPNOTSUPP; 444 } 445 } 446 447 static const u32 w1_temp_config[] = { 448 HWMON_T_INPUT, 449 0 450 }; 451 452 static const struct hwmon_channel_info w1_temp = { 453 .type = hwmon_temp, 454 .config = w1_temp_config, 455 }; 456 457 static const struct hwmon_channel_info *w1_info[] = { 458 &w1_temp, 459 NULL 460 }; 461 462 static const struct hwmon_ops w1_hwmon_ops = { 463 .is_visible = w1_is_visible, 464 .read = w1_read, 465 }; 466 467 static const struct hwmon_chip_info w1_chip_info = { 468 .ops = &w1_hwmon_ops, 469 .info = w1_info, 470 }; 471 #define W1_CHIPINFO (&w1_chip_info) 472 #else 473 #define W1_CHIPINFO NULL 474 #endif 475 476 /* Family operations */ 477 478 static const struct w1_family_ops w1_therm_fops = { 479 .add_slave = w1_therm_add_slave, 480 .remove_slave = w1_therm_remove_slave, 481 .groups = w1_therm_groups, 482 .chip_info = W1_CHIPINFO, 483 }; 484 485 static const struct w1_family_ops w1_ds18s20_fops = { 486 .add_slave = w1_therm_add_slave, 487 .remove_slave = w1_therm_remove_slave, 488 .groups = w1_ds18s20_groups, 489 .chip_info = W1_CHIPINFO, 490 }; 491 492 static const struct w1_family_ops w1_ds28ea00_fops = { 493 .add_slave = w1_therm_add_slave, 494 .remove_slave = w1_therm_remove_slave, 495 .groups = w1_ds28ea00_groups, 496 .chip_info = W1_CHIPINFO, 497 }; 498 499 /* Family binding operations struct */ 500 501 static struct w1_family w1_therm_family_DS18S20 = { 502 .fid = W1_THERM_DS18S20, 503 .fops = &w1_ds18s20_fops, 504 }; 505 506 static struct w1_family w1_therm_family_DS18B20 = { 507 .fid = W1_THERM_DS18B20, 508 .fops = &w1_therm_fops, 509 }; 510 511 static struct w1_family w1_therm_family_DS1822 = { 512 .fid = W1_THERM_DS1822, 513 .fops = &w1_therm_fops, 514 }; 515 516 static struct w1_family w1_therm_family_DS28EA00 = { 517 .fid = W1_THERM_DS28EA00, 518 .fops = &w1_ds28ea00_fops, 519 }; 520 521 static struct w1_family w1_therm_family_DS1825 = { 522 .fid = W1_THERM_DS1825, 523 .fops = &w1_therm_fops, 524 }; 525 526 /* Device dependent func */ 527 528 static inline int w1_DS18B20_convert_time(struct w1_slave *sl) 529 { 530 int ret; 531 532 if (!sl->family_data) 533 return -ENODEV; /* device unknown */ 534 535 if (SLAVE_CONV_TIME_OVERRIDE(sl) != CONV_TIME_DEFAULT) 536 return SLAVE_CONV_TIME_OVERRIDE(sl); 537 538 /* Return the conversion time, depending on resolution, 539 * select maximum conversion time among all compatible devices 540 */ 541 switch (SLAVE_RESOLUTION(sl)) { 542 case 9: 543 ret = 95; 544 break; 545 case 10: 546 ret = 190; 547 break; 548 case 11: 549 ret = 375; 550 break; 551 case 12: 552 ret = 750; 553 break; 554 case 13: 555 ret = 850; /* GX20MH01 only. Datasheet says 500ms, but that's not enough. */ 556 break; 557 case 14: 558 ret = 1600; /* GX20MH01 only. Datasheet says 1000ms - not enough */ 559 break; 560 default: 561 ret = 750; 562 } 563 return ret; 564 } 565 566 static inline int w1_DS18S20_convert_time(struct w1_slave *sl) 567 { 568 if (!sl->family_data) 569 return -ENODEV; /* device unknown */ 570 571 if (SLAVE_CONV_TIME_OVERRIDE(sl) == CONV_TIME_DEFAULT) 572 return 750; /* default for DS18S20 */ 573 else 574 return SLAVE_CONV_TIME_OVERRIDE(sl); 575 } 576 577 static inline int w1_DS1825_convert_time(struct w1_slave *sl) 578 { 579 int ret; 580 581 if (!sl->family_data) 582 return -ENODEV; /* device unknown */ 583 584 if (SLAVE_CONV_TIME_OVERRIDE(sl) != CONV_TIME_DEFAULT) 585 return SLAVE_CONV_TIME_OVERRIDE(sl); 586 587 /* Return the conversion time, depending on resolution, 588 * select maximum conversion time among all compatible devices 589 */ 590 switch (SLAVE_RESOLUTION(sl)) { 591 case 9: 592 ret = 95; 593 break; 594 case 10: 595 ret = 190; 596 break; 597 case 11: 598 ret = 375; 599 break; 600 case 12: 601 ret = 750; 602 break; 603 case 14: 604 ret = 100; /* MAX31850 only. Datasheet says 100ms */ 605 break; 606 default: 607 ret = 750; 608 } 609 return ret; 610 } 611 612 static inline int w1_DS18B20_write_data(struct w1_slave *sl, 613 const u8 *data) 614 { 615 return write_scratchpad(sl, data, 3); 616 } 617 618 static inline int w1_DS18S20_write_data(struct w1_slave *sl, 619 const u8 *data) 620 { 621 /* No config register */ 622 return write_scratchpad(sl, data, 2); 623 } 624 625 static inline int w1_DS18B20_set_resolution(struct w1_slave *sl, int val) 626 { 627 int ret; 628 struct therm_info info, info2; 629 630 /* DS18B20 resolution is 9 to 12 bits */ 631 /* GX20MH01 resolution is 9 to 14 bits */ 632 /* MAX31850 resolution is fixed 14 bits */ 633 if (val < W1_THERM_RESOLUTION_MIN || val > W1_THERM_RESOLUTION_MAX) 634 return -EINVAL; 635 636 /* Calc bit value from resolution */ 637 val = (val - W1_THERM_RESOLUTION_MIN) << W1_THERM_RESOLUTION_SHIFT; 638 639 /* 640 * Read the scratchpad to change only the required bits 641 * (bit5 & bit 6 from byte 4) 642 */ 643 ret = read_scratchpad(sl, &info); 644 645 if (ret) 646 return ret; 647 648 649 info.rom[4] &= ~W1_THERM_RESOLUTION_MASK; 650 info.rom[4] |= val; 651 652 /* Write data in the device RAM */ 653 ret = w1_DS18B20_write_data(sl, info.rom + 2); 654 if (ret) 655 return ret; 656 657 /* Have to read back the resolution to verify an actual value 658 * GX20MH01 and DS18B20 are indistinguishable by family number, but resolutions differ 659 * Some DS18B20 clones don't support resolution change 660 */ 661 ret = read_scratchpad(sl, &info2); 662 if (ret) 663 /* Scratchpad read fail */ 664 return ret; 665 666 if ((info2.rom[4] & W1_THERM_RESOLUTION_MASK) == (info.rom[4] & W1_THERM_RESOLUTION_MASK)) 667 return 0; 668 669 /* Resolution verify error */ 670 return -EIO; 671 } 672 673 static inline int w1_DS18B20_get_resolution(struct w1_slave *sl) 674 { 675 int ret; 676 int resolution; 677 struct therm_info info; 678 679 ret = read_scratchpad(sl, &info); 680 681 if (ret) 682 return ret; 683 684 resolution = ((info.rom[4] & W1_THERM_RESOLUTION_MASK) >> W1_THERM_RESOLUTION_SHIFT) 685 + W1_THERM_RESOLUTION_MIN; 686 /* GX20MH01 has one special case: 687 * >=14 means 14 bits when getting resolution from bit value. 688 * MAX31850 delivers fixed 15 and has 14 bits. 689 * Other devices have no more then 12 bits. 690 */ 691 if (resolution > W1_THERM_RESOLUTION_MAX) 692 resolution = W1_THERM_RESOLUTION_MAX; 693 694 return resolution; 695 } 696 697 /** 698 * w1_DS18B20_convert_temp() - temperature computation for DS18B20 699 * @rom: data read from device RAM (8 data bytes + 1 CRC byte) 700 * 701 * Can be called for any DS18B20 compliant device. 702 * 703 * Return: value in millidegrees Celsius. 704 */ 705 static inline int w1_DS18B20_convert_temp(u8 rom[9]) 706 { 707 u16 bv; 708 s16 t; 709 710 /* Signed 16-bit value to unsigned, cpu order */ 711 bv = le16_to_cpup((__le16 *)rom); 712 713 /* Config register bit R2 = 1 - GX20MH01 in 13 or 14 bit resolution mode */ 714 if (rom[4] & 0x80) { 715 /* Insert two temperature bits from config register */ 716 /* Avoid arithmetic shift of signed value */ 717 bv = (bv << 2) | (rom[4] & 3); 718 t = (s16) bv; /* Degrees, lowest bit is 2^-6 */ 719 return (int)t * 1000 / 64; /* Sign-extend to int; millidegrees */ 720 } 721 t = (s16)bv; /* Degrees, lowest bit is 2^-4 */ 722 return (int)t * 1000 / 16; /* Sign-extend to int; millidegrees */ 723 } 724 725 /** 726 * w1_DS18S20_convert_temp() - temperature computation for DS18S20 727 * @rom: data read from device RAM (8 data bytes + 1 CRC byte) 728 * 729 * Can be called for any DS18S20 compliant device. 730 * 731 * Return: value in millidegrees Celsius. 732 */ 733 static inline int w1_DS18S20_convert_temp(u8 rom[9]) 734 { 735 int t, h; 736 737 if (!rom[7]) { 738 pr_debug("%s: Invalid argument for conversion\n", __func__); 739 return 0; 740 } 741 742 if (rom[1] == 0) 743 t = ((s32)rom[0] >> 1)*1000; 744 else 745 t = 1000*(-1*(s32)(0x100-rom[0]) >> 1); 746 747 t -= 250; 748 h = 1000*((s32)rom[7] - (s32)rom[6]); 749 h /= (s32)rom[7]; 750 t += h; 751 752 return t; 753 } 754 755 /** 756 * w1_DS1825_convert_temp() - temperature computation for DS1825 757 * @rom: data read from device RAM (8 data bytes + 1 CRC byte) 758 * 759 * Can be called for any DS1825 compliant device. 760 * Is used by MAX31850, too 761 * 762 * Return: value in millidegrees Celsius. 763 */ 764 765 static inline int w1_DS1825_convert_temp(u8 rom[9]) 766 { 767 u16 bv; 768 s16 t; 769 770 /* Signed 16-bit value to unsigned, cpu order */ 771 bv = le16_to_cpup((__le16 *)rom); 772 773 /* Config register bit 7 = 1 - MA31850 found, 14 bit resolution */ 774 if (rom[4] & 0x80) { 775 /* Mask out bits 0 (Fault) and 1 (Reserved) */ 776 /* Avoid arithmetic shift of signed value */ 777 bv = (bv & 0xFFFC); /* Degrees, lowest 4 bits are 2^-1, 2^-2 and 2 zero bits */ 778 } 779 t = (s16)bv; /* Degrees, lowest bit is 2^-4 */ 780 return (int)t * 1000 / 16; /* Sign-extend to int; millidegrees */ 781 } 782 783 /* Device capability description */ 784 /* GX20MH01 device shares family number and structure with DS18B20 */ 785 786 static struct w1_therm_family_converter w1_therm_families[] = { 787 { 788 .f = &w1_therm_family_DS18S20, 789 .convert = w1_DS18S20_convert_temp, 790 .get_conversion_time = w1_DS18S20_convert_time, 791 .set_resolution = NULL, /* no config register */ 792 .get_resolution = NULL, /* no config register */ 793 .write_data = w1_DS18S20_write_data, 794 .bulk_read = true 795 }, 796 { 797 .f = &w1_therm_family_DS1822, 798 .convert = w1_DS18B20_convert_temp, 799 .get_conversion_time = w1_DS18B20_convert_time, 800 .set_resolution = w1_DS18B20_set_resolution, 801 .get_resolution = w1_DS18B20_get_resolution, 802 .write_data = w1_DS18B20_write_data, 803 .bulk_read = true 804 }, 805 { 806 /* Also used for GX20MH01 */ 807 .f = &w1_therm_family_DS18B20, 808 .convert = w1_DS18B20_convert_temp, 809 .get_conversion_time = w1_DS18B20_convert_time, 810 .set_resolution = w1_DS18B20_set_resolution, 811 .get_resolution = w1_DS18B20_get_resolution, 812 .write_data = w1_DS18B20_write_data, 813 .bulk_read = true 814 }, 815 { 816 .f = &w1_therm_family_DS28EA00, 817 .convert = w1_DS18B20_convert_temp, 818 .get_conversion_time = w1_DS18B20_convert_time, 819 .set_resolution = w1_DS18B20_set_resolution, 820 .get_resolution = w1_DS18B20_get_resolution, 821 .write_data = w1_DS18B20_write_data, 822 .bulk_read = false 823 }, 824 { 825 /* Also used for MAX31850 */ 826 .f = &w1_therm_family_DS1825, 827 .convert = w1_DS1825_convert_temp, 828 .get_conversion_time = w1_DS1825_convert_time, 829 .set_resolution = w1_DS18B20_set_resolution, 830 .get_resolution = w1_DS18B20_get_resolution, 831 .write_data = w1_DS18B20_write_data, 832 .bulk_read = true 833 } 834 }; 835 836 /* Helpers Functions */ 837 838 /** 839 * device_family() - Retrieve a pointer on &struct w1_therm_family_converter 840 * @sl: slave to retrieve the device specific structure 841 * 842 * Return: pointer to the slaves's family converter, NULL if not known 843 */ 844 static struct w1_therm_family_converter *device_family(struct w1_slave *sl) 845 { 846 struct w1_therm_family_converter *ret = NULL; 847 int i; 848 849 for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) { 850 if (w1_therm_families[i].f->fid == sl->family->fid) { 851 ret = &w1_therm_families[i]; 852 break; 853 } 854 } 855 return ret; 856 } 857 858 /** 859 * bus_mutex_lock() - Acquire the mutex 860 * @lock: w1 bus mutex to acquire 861 * 862 * It try to acquire the mutex W1_THERM_MAX_TRY times and wait 863 * W1_THERM_RETRY_DELAY between 2 attempts. 864 * 865 * Return: true is mutex is acquired and lock, false otherwise 866 */ 867 static inline bool bus_mutex_lock(struct mutex *lock) 868 { 869 int max_trying = W1_THERM_MAX_TRY; 870 871 /* try to acquire the mutex, if not, sleep retry_delay before retry) */ 872 while (mutex_lock_interruptible(lock) != 0 && max_trying > 0) { 873 unsigned long sleep_rem; 874 875 sleep_rem = msleep_interruptible(W1_THERM_RETRY_DELAY); 876 if (!sleep_rem) 877 max_trying--; 878 } 879 880 if (!max_trying) 881 return false; /* Didn't acquire the bus mutex */ 882 883 return true; 884 } 885 886 /** 887 * check_family_data() - Check if family data and specific functions are present 888 * @sl: W1 device data 889 * 890 * Return: 0 - OK, negative value - error 891 */ 892 static int check_family_data(struct w1_slave *sl) 893 { 894 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 895 dev_info(&sl->dev, 896 "%s: Device is not supported by the driver\n", __func__); 897 return -EINVAL; /* No device family */ 898 } 899 return 0; 900 } 901 902 /** 903 * bulk_read_support() - check if slave support bulk read 904 * @sl: device to check the ability 905 * 906 * Return: true if bulk read is supported, false if not or error 907 */ 908 static inline bool bulk_read_support(struct w1_slave *sl) 909 { 910 if (SLAVE_SPECIFIC_FUNC(sl)) 911 return SLAVE_SPECIFIC_FUNC(sl)->bulk_read; 912 913 dev_info(&sl->dev, 914 "%s: Device not supported by the driver\n", __func__); 915 916 return false; /* No device family */ 917 } 918 919 /** 920 * conversion_time() - get the Tconv for the slave 921 * @sl: device to get the conversion time 922 * 923 * On device supporting resolution settings, conversion time depend 924 * on the resolution setting. This helper function get the slave timing, 925 * depending on its current setting. 926 * 927 * Return: conversion time in ms, negative values are kernel error code 928 */ 929 static inline int conversion_time(struct w1_slave *sl) 930 { 931 if (SLAVE_SPECIFIC_FUNC(sl)) 932 return SLAVE_SPECIFIC_FUNC(sl)->get_conversion_time(sl); 933 934 dev_info(&sl->dev, 935 "%s: Device not supported by the driver\n", __func__); 936 937 return -ENODEV; /* No device family */ 938 } 939 940 /** 941 * temperature_from_RAM() - Convert the read info to temperature 942 * @sl: device that sent the RAM data 943 * @rom: read value on the slave device RAM 944 * 945 * Device dependent, the function bind the correct computation method. 946 * 947 * Return: temperature in 1/1000degC, 0 on error. 948 */ 949 static inline int temperature_from_RAM(struct w1_slave *sl, u8 rom[9]) 950 { 951 if (SLAVE_SPECIFIC_FUNC(sl)) 952 return SLAVE_SPECIFIC_FUNC(sl)->convert(rom); 953 954 dev_info(&sl->dev, 955 "%s: Device not supported by the driver\n", __func__); 956 957 return 0; /* No device family */ 958 } 959 960 /** 961 * int_to_short() - Safe casting of int to short 962 * 963 * @i: integer to be converted to short 964 * 965 * Device register use 1 byte to store signed integer. 966 * This helper function convert the int in a signed short, 967 * using the min/max values that device can measure as limits. 968 * min/max values are defined by macro. 969 * 970 * Return: a short in the range of min/max value 971 */ 972 static inline s8 int_to_short(int i) 973 { 974 /* Prepare to cast to short by eliminating out of range values */ 975 i = clamp(i, MIN_TEMP, MAX_TEMP); 976 return (s8) i; 977 } 978 979 /* Interface Functions */ 980 981 static int w1_therm_add_slave(struct w1_slave *sl) 982 { 983 struct w1_therm_family_converter *sl_family_conv; 984 985 /* Allocate memory */ 986 sl->family_data = kzalloc(sizeof(struct w1_therm_family_data), 987 GFP_KERNEL); 988 if (!sl->family_data) 989 return -ENOMEM; 990 991 atomic_set(THERM_REFCNT(sl->family_data), 1); 992 993 /* Get a pointer to the device specific function struct */ 994 sl_family_conv = device_family(sl); 995 if (!sl_family_conv) { 996 kfree(sl->family_data); 997 return -ENODEV; 998 } 999 /* save this pointer to the device structure */ 1000 SLAVE_SPECIFIC_FUNC(sl) = sl_family_conv; 1001 1002 if (bulk_read_support(sl)) { 1003 /* 1004 * add the sys entry to trigger bulk_read 1005 * at master level only the 1st time 1006 */ 1007 if (!bulk_read_device_counter) { 1008 int err = device_create_file(&sl->master->dev, 1009 &dev_attr_therm_bulk_read); 1010 1011 if (err) 1012 dev_warn(&sl->dev, 1013 "%s: Device has been added, but bulk read is unavailable. err=%d\n", 1014 __func__, err); 1015 } 1016 /* Increment the counter */ 1017 bulk_read_device_counter++; 1018 } 1019 1020 /* Getting the power mode of the device {external, parasite} */ 1021 SLAVE_POWERMODE(sl) = read_powermode(sl); 1022 1023 if (SLAVE_POWERMODE(sl) < 0) { 1024 /* no error returned as device has been added */ 1025 dev_warn(&sl->dev, 1026 "%s: Device has been added, but power_mode may be corrupted. err=%d\n", 1027 __func__, SLAVE_POWERMODE(sl)); 1028 } 1029 1030 /* Getting the resolution of the device */ 1031 if (SLAVE_SPECIFIC_FUNC(sl)->get_resolution) { 1032 SLAVE_RESOLUTION(sl) = 1033 SLAVE_SPECIFIC_FUNC(sl)->get_resolution(sl); 1034 if (SLAVE_RESOLUTION(sl) < 0) { 1035 /* no error returned as device has been added */ 1036 dev_warn(&sl->dev, 1037 "%s:Device has been added, but resolution may be corrupted. err=%d\n", 1038 __func__, SLAVE_RESOLUTION(sl)); 1039 } 1040 } 1041 1042 /* Finally initialize convert_triggered flag */ 1043 SLAVE_CONVERT_TRIGGERED(sl) = 0; 1044 1045 return 0; 1046 } 1047 1048 static void w1_therm_remove_slave(struct w1_slave *sl) 1049 { 1050 int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data)); 1051 1052 if (bulk_read_support(sl)) { 1053 bulk_read_device_counter--; 1054 /* Delete the entry if no more device support the feature */ 1055 if (!bulk_read_device_counter) 1056 device_remove_file(&sl->master->dev, 1057 &dev_attr_therm_bulk_read); 1058 } 1059 1060 while (refcnt) { 1061 msleep(1000); 1062 refcnt = atomic_read(THERM_REFCNT(sl->family_data)); 1063 } 1064 kfree(sl->family_data); 1065 sl->family_data = NULL; 1066 } 1067 1068 /* Hardware Functions */ 1069 1070 /* Safe version of reset_select_slave - avoid using the one in w_io.c */ 1071 static int reset_select_slave(struct w1_slave *sl) 1072 { 1073 u8 match[9] = { W1_MATCH_ROM, }; 1074 u64 rn = le64_to_cpu(*((u64 *)&sl->reg_num)); 1075 1076 if (w1_reset_bus(sl->master)) 1077 return -ENODEV; 1078 1079 memcpy(&match[1], &rn, 8); 1080 w1_write_block(sl->master, match, 9); 1081 1082 return 0; 1083 } 1084 1085 /** 1086 * w1_poll_completion - Poll for operation completion, with timeout 1087 * @dev_master: the device master of the bus 1088 * @tout_ms: timeout in milliseconds 1089 * 1090 * The device is answering 0's while an operation is in progress and 1's after it completes 1091 * Timeout may happen if the previous command was not recognised due to a line noise 1092 * 1093 * Return: 0 - OK, negative error - timeout 1094 */ 1095 static int w1_poll_completion(struct w1_master *dev_master, int tout_ms) 1096 { 1097 int i; 1098 1099 for (i = 0; i < tout_ms/W1_POLL_PERIOD; i++) { 1100 /* Delay is before poll, for device to recognize a command */ 1101 msleep(W1_POLL_PERIOD); 1102 1103 /* Compare all 8 bits to mitigate a noise on the bus */ 1104 if (w1_read_8(dev_master) == 0xFF) 1105 break; 1106 } 1107 if (i == tout_ms/W1_POLL_PERIOD) 1108 return -EIO; 1109 1110 return 0; 1111 } 1112 1113 static int convert_t(struct w1_slave *sl, struct therm_info *info) 1114 { 1115 struct w1_master *dev_master = sl->master; 1116 int max_trying = W1_THERM_MAX_TRY; 1117 int t_conv; 1118 int ret = -ENODEV; 1119 bool strong_pullup; 1120 1121 if (!sl->family_data) 1122 goto error; 1123 1124 strong_pullup = (w1_strong_pullup == 2 || 1125 (!SLAVE_POWERMODE(sl) && 1126 w1_strong_pullup)); 1127 1128 if (strong_pullup && SLAVE_FEATURES(sl) & W1_THERM_POLL_COMPLETION) { 1129 dev_warn(&sl->dev, 1130 "%s: Disabling W1_THERM_POLL_COMPLETION in parasite power mode.\n", 1131 __func__); 1132 SLAVE_FEATURES(sl) &= ~W1_THERM_POLL_COMPLETION; 1133 } 1134 1135 /* get conversion duration device and id dependent */ 1136 t_conv = conversion_time(sl); 1137 1138 memset(info->rom, 0, sizeof(info->rom)); 1139 1140 /* prevent the slave from going away in sleep */ 1141 atomic_inc(THERM_REFCNT(sl->family_data)); 1142 1143 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1144 ret = -EAGAIN; /* Didn't acquire the mutex */ 1145 goto dec_refcnt; 1146 } 1147 1148 while (max_trying-- && ret) { /* ret should be 0 */ 1149 1150 info->verdict = 0; 1151 info->crc = 0; 1152 /* safe version to select slave */ 1153 if (!reset_select_slave(sl)) { 1154 unsigned long sleep_rem; 1155 1156 /* 750ms strong pullup (or delay) after the convert */ 1157 if (strong_pullup) 1158 w1_next_pullup(dev_master, t_conv); 1159 1160 w1_write_8(dev_master, W1_CONVERT_TEMP); 1161 1162 if (strong_pullup) { /*some device need pullup */ 1163 sleep_rem = msleep_interruptible(t_conv); 1164 if (sleep_rem != 0) { 1165 ret = -EINTR; 1166 goto mt_unlock; 1167 } 1168 mutex_unlock(&dev_master->bus_mutex); 1169 } else { /*no device need pullup */ 1170 if (SLAVE_FEATURES(sl) & W1_THERM_POLL_COMPLETION) { 1171 ret = w1_poll_completion(dev_master, W1_POLL_CONVERT_TEMP); 1172 if (ret) { 1173 dev_dbg(&sl->dev, "%s: Timeout\n", __func__); 1174 goto mt_unlock; 1175 } 1176 mutex_unlock(&dev_master->bus_mutex); 1177 } else { 1178 /* Fixed delay */ 1179 mutex_unlock(&dev_master->bus_mutex); 1180 sleep_rem = msleep_interruptible(t_conv); 1181 if (sleep_rem != 0) { 1182 ret = -EINTR; 1183 goto dec_refcnt; 1184 } 1185 } 1186 } 1187 ret = read_scratchpad(sl, info); 1188 1189 /* If enabled, check for conversion success */ 1190 if ((SLAVE_FEATURES(sl) & W1_THERM_CHECK_RESULT) && 1191 (info->rom[6] == 0xC) && 1192 ((info->rom[1] == 0x5 && info->rom[0] == 0x50) || 1193 (info->rom[1] == 0x7 && info->rom[0] == 0xFF)) 1194 ) { 1195 /* Invalid reading (scratchpad byte 6 = 0xC) 1196 * due to insufficient conversion time 1197 * or power failure. 1198 */ 1199 ret = -EIO; 1200 } 1201 1202 goto dec_refcnt; 1203 } 1204 1205 } 1206 1207 mt_unlock: 1208 mutex_unlock(&dev_master->bus_mutex); 1209 dec_refcnt: 1210 atomic_dec(THERM_REFCNT(sl->family_data)); 1211 error: 1212 return ret; 1213 } 1214 1215 static int conv_time_measure(struct w1_slave *sl, int *conv_time) 1216 { 1217 struct therm_info inf, 1218 *info = &inf; 1219 struct w1_master *dev_master = sl->master; 1220 int max_trying = W1_THERM_MAX_TRY; 1221 int ret = -ENODEV; 1222 bool strong_pullup; 1223 1224 if (!sl->family_data) 1225 goto error; 1226 1227 strong_pullup = (w1_strong_pullup == 2 || 1228 (!SLAVE_POWERMODE(sl) && 1229 w1_strong_pullup)); 1230 1231 if (strong_pullup) { 1232 pr_info("%s: Measure with strong_pullup is not supported.\n", __func__); 1233 return -EINVAL; 1234 } 1235 1236 memset(info->rom, 0, sizeof(info->rom)); 1237 1238 /* prevent the slave from going away in sleep */ 1239 atomic_inc(THERM_REFCNT(sl->family_data)); 1240 1241 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1242 ret = -EAGAIN; /* Didn't acquire the mutex */ 1243 goto dec_refcnt; 1244 } 1245 1246 while (max_trying-- && ret) { /* ret should be 0 */ 1247 info->verdict = 0; 1248 info->crc = 0; 1249 /* safe version to select slave */ 1250 if (!reset_select_slave(sl)) { 1251 int j_start, j_end; 1252 1253 /*no device need pullup */ 1254 w1_write_8(dev_master, W1_CONVERT_TEMP); 1255 1256 j_start = jiffies; 1257 ret = w1_poll_completion(dev_master, W1_POLL_CONVERT_TEMP); 1258 if (ret) { 1259 dev_dbg(&sl->dev, "%s: Timeout\n", __func__); 1260 goto mt_unlock; 1261 } 1262 j_end = jiffies; 1263 /* 1.2x increase for variation and changes over temperature range */ 1264 *conv_time = jiffies_to_msecs(j_end-j_start)*12/10; 1265 pr_debug("W1 Measure complete, conv_time = %d, HZ=%d.\n", 1266 *conv_time, HZ); 1267 if (*conv_time <= CONV_TIME_MEASURE) { 1268 ret = -EIO; 1269 goto mt_unlock; 1270 } 1271 mutex_unlock(&dev_master->bus_mutex); 1272 ret = read_scratchpad(sl, info); 1273 goto dec_refcnt; 1274 } 1275 1276 } 1277 mt_unlock: 1278 mutex_unlock(&dev_master->bus_mutex); 1279 dec_refcnt: 1280 atomic_dec(THERM_REFCNT(sl->family_data)); 1281 error: 1282 return ret; 1283 } 1284 1285 static int read_scratchpad(struct w1_slave *sl, struct therm_info *info) 1286 { 1287 struct w1_master *dev_master = sl->master; 1288 int max_trying = W1_THERM_MAX_TRY; 1289 int ret = -ENODEV; 1290 1291 info->verdict = 0; 1292 1293 if (!sl->family_data) 1294 goto error; 1295 1296 memset(info->rom, 0, sizeof(info->rom)); 1297 1298 /* prevent the slave from going away in sleep */ 1299 atomic_inc(THERM_REFCNT(sl->family_data)); 1300 1301 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1302 ret = -EAGAIN; /* Didn't acquire the mutex */ 1303 goto dec_refcnt; 1304 } 1305 1306 while (max_trying-- && ret) { /* ret should be 0 */ 1307 /* safe version to select slave */ 1308 if (!reset_select_slave(sl)) { 1309 u8 nb_bytes_read; 1310 1311 w1_write_8(dev_master, W1_READ_SCRATCHPAD); 1312 1313 nb_bytes_read = w1_read_block(dev_master, info->rom, 9); 1314 if (nb_bytes_read != 9) { 1315 dev_warn(&sl->dev, 1316 "w1_read_block(): returned %u instead of 9.\n", 1317 nb_bytes_read); 1318 ret = -EIO; 1319 } 1320 1321 info->crc = w1_calc_crc8(info->rom, 8); 1322 1323 if (info->rom[8] == info->crc) { 1324 info->verdict = 1; 1325 ret = 0; 1326 } else 1327 ret = -EIO; /* CRC not checked */ 1328 } 1329 1330 } 1331 mutex_unlock(&dev_master->bus_mutex); 1332 1333 dec_refcnt: 1334 atomic_dec(THERM_REFCNT(sl->family_data)); 1335 error: 1336 return ret; 1337 } 1338 1339 static int write_scratchpad(struct w1_slave *sl, const u8 *data, u8 nb_bytes) 1340 { 1341 struct w1_master *dev_master = sl->master; 1342 int max_trying = W1_THERM_MAX_TRY; 1343 int ret = -ENODEV; 1344 1345 if (!sl->family_data) 1346 goto error; 1347 1348 /* prevent the slave from going away in sleep */ 1349 atomic_inc(THERM_REFCNT(sl->family_data)); 1350 1351 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1352 ret = -EAGAIN; /* Didn't acquire the mutex */ 1353 goto dec_refcnt; 1354 } 1355 1356 while (max_trying-- && ret) { /* ret should be 0 */ 1357 /* safe version to select slave */ 1358 if (!reset_select_slave(sl)) { 1359 w1_write_8(dev_master, W1_WRITE_SCRATCHPAD); 1360 w1_write_block(dev_master, data, nb_bytes); 1361 ret = 0; 1362 } 1363 } 1364 mutex_unlock(&dev_master->bus_mutex); 1365 1366 dec_refcnt: 1367 atomic_dec(THERM_REFCNT(sl->family_data)); 1368 error: 1369 return ret; 1370 } 1371 1372 static int copy_scratchpad(struct w1_slave *sl) 1373 { 1374 struct w1_master *dev_master = sl->master; 1375 int max_trying = W1_THERM_MAX_TRY; 1376 int t_write, ret = -ENODEV; 1377 bool strong_pullup; 1378 1379 if (!sl->family_data) 1380 goto error; 1381 1382 t_write = W1_THERM_EEPROM_WRITE_DELAY; 1383 strong_pullup = (w1_strong_pullup == 2 || 1384 (!SLAVE_POWERMODE(sl) && 1385 w1_strong_pullup)); 1386 1387 /* prevent the slave from going away in sleep */ 1388 atomic_inc(THERM_REFCNT(sl->family_data)); 1389 1390 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1391 ret = -EAGAIN; /* Didn't acquire the mutex */ 1392 goto dec_refcnt; 1393 } 1394 1395 while (max_trying-- && ret) { /* ret should be 0 */ 1396 /* safe version to select slave */ 1397 if (!reset_select_slave(sl)) { 1398 unsigned long sleep_rem; 1399 1400 /* 10ms strong pullup (or delay) after the convert */ 1401 if (strong_pullup) 1402 w1_next_pullup(dev_master, t_write); 1403 1404 w1_write_8(dev_master, W1_COPY_SCRATCHPAD); 1405 1406 if (strong_pullup) { 1407 sleep_rem = msleep_interruptible(t_write); 1408 if (sleep_rem != 0) { 1409 ret = -EINTR; 1410 goto mt_unlock; 1411 } 1412 } 1413 ret = 0; 1414 } 1415 1416 } 1417 1418 mt_unlock: 1419 mutex_unlock(&dev_master->bus_mutex); 1420 dec_refcnt: 1421 atomic_dec(THERM_REFCNT(sl->family_data)); 1422 error: 1423 return ret; 1424 } 1425 1426 static int recall_eeprom(struct w1_slave *sl) 1427 { 1428 struct w1_master *dev_master = sl->master; 1429 int max_trying = W1_THERM_MAX_TRY; 1430 int ret = -ENODEV; 1431 1432 if (!sl->family_data) 1433 goto error; 1434 1435 /* prevent the slave from going away in sleep */ 1436 atomic_inc(THERM_REFCNT(sl->family_data)); 1437 1438 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1439 ret = -EAGAIN; /* Didn't acquire the mutex */ 1440 goto dec_refcnt; 1441 } 1442 1443 while (max_trying-- && ret) { /* ret should be 0 */ 1444 /* safe version to select slave */ 1445 if (!reset_select_slave(sl)) { 1446 1447 w1_write_8(dev_master, W1_RECALL_EEPROM); 1448 ret = w1_poll_completion(dev_master, W1_POLL_RECALL_EEPROM); 1449 } 1450 1451 } 1452 1453 mutex_unlock(&dev_master->bus_mutex); 1454 1455 dec_refcnt: 1456 atomic_dec(THERM_REFCNT(sl->family_data)); 1457 error: 1458 return ret; 1459 } 1460 1461 static int read_powermode(struct w1_slave *sl) 1462 { 1463 struct w1_master *dev_master = sl->master; 1464 int max_trying = W1_THERM_MAX_TRY; 1465 int ret = -ENODEV; 1466 1467 if (!sl->family_data) 1468 goto error; 1469 1470 /* prevent the slave from going away in sleep */ 1471 atomic_inc(THERM_REFCNT(sl->family_data)); 1472 1473 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1474 ret = -EAGAIN; /* Didn't acquire the mutex */ 1475 goto dec_refcnt; 1476 } 1477 1478 while ((max_trying--) && (ret < 0)) { 1479 /* safe version to select slave */ 1480 if (!reset_select_slave(sl)) { 1481 w1_write_8(dev_master, W1_READ_PSUPPLY); 1482 /* 1483 * Emit a read time slot and read only one bit, 1484 * 1 is externally powered, 1485 * 0 is parasite powered 1486 */ 1487 ret = w1_touch_bit(dev_master, 1); 1488 /* ret should be either 1 either 0 */ 1489 } 1490 } 1491 mutex_unlock(&dev_master->bus_mutex); 1492 1493 dec_refcnt: 1494 atomic_dec(THERM_REFCNT(sl->family_data)); 1495 error: 1496 return ret; 1497 } 1498 1499 static int trigger_bulk_read(struct w1_master *dev_master) 1500 { 1501 struct w1_slave *sl = NULL; /* used to iterate through slaves */ 1502 int max_trying = W1_THERM_MAX_TRY; 1503 int t_conv = 0; 1504 int ret = -ENODEV; 1505 bool strong_pullup = false; 1506 1507 /* 1508 * Check whether there are parasite powered device on the bus, 1509 * and compute duration of conversion for these devices 1510 * so we can apply a strong pullup if required 1511 */ 1512 list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { 1513 if (!sl->family_data) 1514 goto error; 1515 if (bulk_read_support(sl)) { 1516 int t_cur = conversion_time(sl); 1517 1518 t_conv = t_cur > t_conv ? t_cur : t_conv; 1519 strong_pullup = strong_pullup || 1520 (w1_strong_pullup == 2 || 1521 (!SLAVE_POWERMODE(sl) && 1522 w1_strong_pullup)); 1523 } 1524 } 1525 1526 /* 1527 * t_conv is the max conversion time required on the bus 1528 * If its 0, no device support the bulk read feature 1529 */ 1530 if (!t_conv) 1531 goto error; 1532 1533 if (!bus_mutex_lock(&dev_master->bus_mutex)) { 1534 ret = -EAGAIN; /* Didn't acquire the mutex */ 1535 goto error; 1536 } 1537 1538 while ((max_trying--) && (ret < 0)) { /* ret should be either 0 */ 1539 1540 if (!w1_reset_bus(dev_master)) { /* Just reset the bus */ 1541 unsigned long sleep_rem; 1542 1543 w1_write_8(dev_master, W1_SKIP_ROM); 1544 1545 if (strong_pullup) /* Apply pullup if required */ 1546 w1_next_pullup(dev_master, t_conv); 1547 1548 w1_write_8(dev_master, W1_CONVERT_TEMP); 1549 1550 /* set a flag to instruct that converT pending */ 1551 list_for_each_entry(sl, 1552 &dev_master->slist, w1_slave_entry) { 1553 if (bulk_read_support(sl)) 1554 SLAVE_CONVERT_TRIGGERED(sl) = -1; 1555 } 1556 1557 if (strong_pullup) { /* some device need pullup */ 1558 sleep_rem = msleep_interruptible(t_conv); 1559 if (sleep_rem != 0) { 1560 ret = -EINTR; 1561 goto mt_unlock; 1562 } 1563 mutex_unlock(&dev_master->bus_mutex); 1564 } else { 1565 mutex_unlock(&dev_master->bus_mutex); 1566 sleep_rem = msleep_interruptible(t_conv); 1567 if (sleep_rem != 0) { 1568 ret = -EINTR; 1569 goto set_flag; 1570 } 1571 } 1572 ret = 0; 1573 goto set_flag; 1574 } 1575 } 1576 1577 mt_unlock: 1578 mutex_unlock(&dev_master->bus_mutex); 1579 set_flag: 1580 /* set a flag to register convsersion is done */ 1581 list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { 1582 if (bulk_read_support(sl)) 1583 SLAVE_CONVERT_TRIGGERED(sl) = 1; 1584 } 1585 error: 1586 return ret; 1587 } 1588 1589 /* Sysfs Interface definition */ 1590 1591 static ssize_t w1_slave_show(struct device *device, 1592 struct device_attribute *attr, char *buf) 1593 { 1594 struct w1_slave *sl = dev_to_w1_slave(device); 1595 struct therm_info info; 1596 u8 *family_data = sl->family_data; 1597 int ret, i; 1598 ssize_t c = PAGE_SIZE; 1599 1600 if (bulk_read_support(sl)) { 1601 if (SLAVE_CONVERT_TRIGGERED(sl) < 0) { 1602 dev_dbg(device, 1603 "%s: Conversion in progress, retry later\n", 1604 __func__); 1605 return 0; 1606 } else if (SLAVE_CONVERT_TRIGGERED(sl) > 0) { 1607 /* A bulk read has been issued, read the device RAM */ 1608 ret = read_scratchpad(sl, &info); 1609 SLAVE_CONVERT_TRIGGERED(sl) = 0; 1610 } else 1611 ret = convert_t(sl, &info); 1612 } else 1613 ret = convert_t(sl, &info); 1614 1615 if (ret < 0) { 1616 dev_dbg(device, 1617 "%s: Temperature data may be corrupted. err=%d\n", 1618 __func__, ret); 1619 return 0; 1620 } 1621 1622 for (i = 0; i < 9; ++i) 1623 c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", info.rom[i]); 1624 c -= snprintf(buf + PAGE_SIZE - c, c, ": crc=%02x %s\n", 1625 info.crc, (info.verdict) ? "YES" : "NO"); 1626 1627 if (info.verdict) 1628 memcpy(family_data, info.rom, sizeof(info.rom)); 1629 else 1630 dev_warn(device, "%s:Read failed CRC check\n", __func__); 1631 1632 for (i = 0; i < 9; ++i) 1633 c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", 1634 ((u8 *)family_data)[i]); 1635 1636 c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n", 1637 temperature_from_RAM(sl, info.rom)); 1638 1639 ret = PAGE_SIZE - c; 1640 return ret; 1641 } 1642 1643 static ssize_t w1_slave_store(struct device *device, 1644 struct device_attribute *attr, const char *buf, 1645 size_t size) 1646 { 1647 int val, ret = 0; 1648 struct w1_slave *sl = dev_to_w1_slave(device); 1649 1650 ret = kstrtoint(buf, 10, &val); /* converting user entry to int */ 1651 1652 if (ret) { /* conversion error */ 1653 dev_info(device, 1654 "%s: conversion error. err= %d\n", __func__, ret); 1655 return size; /* return size to avoid call back again */ 1656 } 1657 1658 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 1659 dev_info(device, 1660 "%s: Device not supported by the driver\n", __func__); 1661 return size; /* No device family */ 1662 } 1663 1664 if (val == 0) /* val=0 : trigger a EEPROM save */ 1665 ret = copy_scratchpad(sl); 1666 else { 1667 if (SLAVE_SPECIFIC_FUNC(sl)->set_resolution) 1668 ret = SLAVE_SPECIFIC_FUNC(sl)->set_resolution(sl, val); 1669 } 1670 1671 if (ret) { 1672 dev_warn(device, "%s: Set resolution - error %d\n", __func__, ret); 1673 /* Propagate error to userspace */ 1674 return ret; 1675 } 1676 SLAVE_RESOLUTION(sl) = val; 1677 /* Reset the conversion time to default - it depends on resolution */ 1678 SLAVE_CONV_TIME_OVERRIDE(sl) = CONV_TIME_DEFAULT; 1679 1680 return size; /* always return size to avoid infinite calling */ 1681 } 1682 1683 static ssize_t temperature_show(struct device *device, 1684 struct device_attribute *attr, char *buf) 1685 { 1686 struct w1_slave *sl = dev_to_w1_slave(device); 1687 struct therm_info info; 1688 int ret = 0; 1689 1690 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 1691 dev_info(device, 1692 "%s: Device not supported by the driver\n", __func__); 1693 return 0; /* No device family */ 1694 } 1695 1696 if (bulk_read_support(sl)) { 1697 if (SLAVE_CONVERT_TRIGGERED(sl) < 0) { 1698 dev_dbg(device, 1699 "%s: Conversion in progress, retry later\n", 1700 __func__); 1701 return 0; 1702 } else if (SLAVE_CONVERT_TRIGGERED(sl) > 0) { 1703 /* A bulk read has been issued, read the device RAM */ 1704 ret = read_scratchpad(sl, &info); 1705 SLAVE_CONVERT_TRIGGERED(sl) = 0; 1706 } else 1707 ret = convert_t(sl, &info); 1708 } else 1709 ret = convert_t(sl, &info); 1710 1711 if (ret < 0) { 1712 dev_dbg(device, 1713 "%s: Temperature data may be corrupted. err=%d\n", 1714 __func__, ret); 1715 return 0; 1716 } 1717 1718 return sprintf(buf, "%d\n", temperature_from_RAM(sl, info.rom)); 1719 } 1720 1721 static ssize_t ext_power_show(struct device *device, 1722 struct device_attribute *attr, char *buf) 1723 { 1724 struct w1_slave *sl = dev_to_w1_slave(device); 1725 1726 if (!sl->family_data) { 1727 dev_info(device, 1728 "%s: Device not supported by the driver\n", __func__); 1729 return 0; /* No device family */ 1730 } 1731 1732 /* Getting the power mode of the device {external, parasite} */ 1733 SLAVE_POWERMODE(sl) = read_powermode(sl); 1734 1735 if (SLAVE_POWERMODE(sl) < 0) { 1736 dev_dbg(device, 1737 "%s: Power_mode may be corrupted. err=%d\n", 1738 __func__, SLAVE_POWERMODE(sl)); 1739 } 1740 return sprintf(buf, "%d\n", SLAVE_POWERMODE(sl)); 1741 } 1742 1743 static ssize_t resolution_show(struct device *device, 1744 struct device_attribute *attr, char *buf) 1745 { 1746 struct w1_slave *sl = dev_to_w1_slave(device); 1747 1748 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 1749 dev_info(device, 1750 "%s: Device not supported by the driver\n", __func__); 1751 return 0; /* No device family */ 1752 } 1753 1754 /* get the correct function depending on the device */ 1755 SLAVE_RESOLUTION(sl) = SLAVE_SPECIFIC_FUNC(sl)->get_resolution(sl); 1756 if (SLAVE_RESOLUTION(sl) < 0) { 1757 dev_dbg(device, 1758 "%s: Resolution may be corrupted. err=%d\n", 1759 __func__, SLAVE_RESOLUTION(sl)); 1760 } 1761 1762 return sprintf(buf, "%d\n", SLAVE_RESOLUTION(sl)); 1763 } 1764 1765 static ssize_t resolution_store(struct device *device, 1766 struct device_attribute *attr, const char *buf, size_t size) 1767 { 1768 struct w1_slave *sl = dev_to_w1_slave(device); 1769 int val; 1770 int ret = 0; 1771 1772 ret = kstrtoint(buf, 10, &val); /* converting user entry to int */ 1773 1774 if (ret) { /* conversion error */ 1775 dev_info(device, 1776 "%s: conversion error. err= %d\n", __func__, ret); 1777 return size; /* return size to avoid call back again */ 1778 } 1779 1780 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 1781 dev_info(device, 1782 "%s: Device not supported by the driver\n", __func__); 1783 return size; /* No device family */ 1784 } 1785 1786 /* 1787 * Don't deal with the val enterd by user, 1788 * only device knows what is correct or not 1789 */ 1790 1791 /* get the correct function depending on the device */ 1792 ret = SLAVE_SPECIFIC_FUNC(sl)->set_resolution(sl, val); 1793 1794 if (ret) 1795 return ret; 1796 1797 SLAVE_RESOLUTION(sl) = val; 1798 /* Reset the conversion time to default because it depends on resolution */ 1799 SLAVE_CONV_TIME_OVERRIDE(sl) = CONV_TIME_DEFAULT; 1800 1801 return size; 1802 } 1803 1804 static ssize_t eeprom_cmd_store(struct device *device, 1805 struct device_attribute *attr, const char *buf, size_t size) 1806 { 1807 struct w1_slave *sl = dev_to_w1_slave(device); 1808 int ret = -EINVAL; /* Invalid argument */ 1809 1810 if (size == sizeof(EEPROM_CMD_WRITE)) { 1811 if (!strncmp(buf, EEPROM_CMD_WRITE, sizeof(EEPROM_CMD_WRITE)-1)) 1812 ret = copy_scratchpad(sl); 1813 } else if (size == sizeof(EEPROM_CMD_READ)) { 1814 if (!strncmp(buf, EEPROM_CMD_READ, sizeof(EEPROM_CMD_READ)-1)) 1815 ret = recall_eeprom(sl); 1816 } 1817 1818 if (ret) 1819 dev_info(device, "%s: error in process %d\n", __func__, ret); 1820 1821 return size; 1822 } 1823 1824 static ssize_t alarms_show(struct device *device, 1825 struct device_attribute *attr, char *buf) 1826 { 1827 struct w1_slave *sl = dev_to_w1_slave(device); 1828 int ret; 1829 s8 th = 0, tl = 0; 1830 struct therm_info scratchpad; 1831 1832 ret = read_scratchpad(sl, &scratchpad); 1833 1834 if (!ret) { 1835 th = scratchpad.rom[2]; /* TH is byte 2 */ 1836 tl = scratchpad.rom[3]; /* TL is byte 3 */ 1837 } else { 1838 dev_info(device, 1839 "%s: error reading alarms register %d\n", 1840 __func__, ret); 1841 } 1842 1843 return sprintf(buf, "%hd %hd\n", tl, th); 1844 } 1845 1846 static ssize_t alarms_store(struct device *device, 1847 struct device_attribute *attr, const char *buf, size_t size) 1848 { 1849 struct w1_slave *sl = dev_to_w1_slave(device); 1850 struct therm_info info; 1851 u8 new_config_register[3]; /* array of data to be written */ 1852 int temp, ret; 1853 char *token = NULL; 1854 s8 tl, th; /* 1 byte per value + temp ring order */ 1855 char *p_args, *orig; 1856 1857 p_args = orig = kmalloc(size, GFP_KERNEL); 1858 /* Safe string copys as buf is const */ 1859 if (!p_args) { 1860 dev_warn(device, 1861 "%s: error unable to allocate memory %d\n", 1862 __func__, -ENOMEM); 1863 return size; 1864 } 1865 strcpy(p_args, buf); 1866 1867 /* Split string using space char */ 1868 token = strsep(&p_args, " "); 1869 1870 if (!token) { 1871 dev_info(device, 1872 "%s: error parsing args %d\n", __func__, -EINVAL); 1873 goto free_m; 1874 } 1875 1876 /* Convert 1st entry to int */ 1877 ret = kstrtoint (token, 10, &temp); 1878 if (ret) { 1879 dev_info(device, 1880 "%s: error parsing args %d\n", __func__, ret); 1881 goto free_m; 1882 } 1883 1884 tl = int_to_short(temp); 1885 1886 /* Split string using space char */ 1887 token = strsep(&p_args, " "); 1888 if (!token) { 1889 dev_info(device, 1890 "%s: error parsing args %d\n", __func__, -EINVAL); 1891 goto free_m; 1892 } 1893 /* Convert 2nd entry to int */ 1894 ret = kstrtoint (token, 10, &temp); 1895 if (ret) { 1896 dev_info(device, 1897 "%s: error parsing args %d\n", __func__, ret); 1898 goto free_m; 1899 } 1900 1901 /* Prepare to cast to short by eliminating out of range values */ 1902 th = int_to_short(temp); 1903 1904 /* Reorder if required th and tl */ 1905 if (tl > th) 1906 swap(tl, th); 1907 1908 /* 1909 * Read the scratchpad to change only the required bits 1910 * (th : byte 2 - tl: byte 3) 1911 */ 1912 ret = read_scratchpad(sl, &info); 1913 if (!ret) { 1914 new_config_register[0] = th; /* Byte 2 */ 1915 new_config_register[1] = tl; /* Byte 3 */ 1916 new_config_register[2] = info.rom[4];/* Byte 4 */ 1917 } else { 1918 dev_info(device, 1919 "%s: error reading from the slave device %d\n", 1920 __func__, ret); 1921 goto free_m; 1922 } 1923 1924 /* Write data in the device RAM */ 1925 if (!SLAVE_SPECIFIC_FUNC(sl)) { 1926 dev_info(device, 1927 "%s: Device not supported by the driver %d\n", 1928 __func__, -ENODEV); 1929 goto free_m; 1930 } 1931 1932 ret = SLAVE_SPECIFIC_FUNC(sl)->write_data(sl, new_config_register); 1933 if (ret) 1934 dev_info(device, 1935 "%s: error writing to the slave device %d\n", 1936 __func__, ret); 1937 1938 free_m: 1939 /* free allocated memory */ 1940 kfree(orig); 1941 1942 return size; 1943 } 1944 1945 static ssize_t therm_bulk_read_store(struct device *device, 1946 struct device_attribute *attr, const char *buf, size_t size) 1947 { 1948 struct w1_master *dev_master = dev_to_w1_master(device); 1949 int ret = -EINVAL; /* Invalid argument */ 1950 1951 if (size == sizeof(BULK_TRIGGER_CMD)) 1952 if (!strncmp(buf, BULK_TRIGGER_CMD, 1953 sizeof(BULK_TRIGGER_CMD)-1)) 1954 ret = trigger_bulk_read(dev_master); 1955 1956 if (ret) 1957 dev_info(device, 1958 "%s: unable to trigger a bulk read on the bus. err=%d\n", 1959 __func__, ret); 1960 1961 return size; 1962 } 1963 1964 static ssize_t therm_bulk_read_show(struct device *device, 1965 struct device_attribute *attr, char *buf) 1966 { 1967 struct w1_master *dev_master = dev_to_w1_master(device); 1968 struct w1_slave *sl = NULL; 1969 int ret = 0; 1970 1971 list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { 1972 if (sl->family_data) { 1973 if (bulk_read_support(sl)) { 1974 if (SLAVE_CONVERT_TRIGGERED(sl) == -1) { 1975 ret = -1; 1976 goto show_result; 1977 } 1978 if (SLAVE_CONVERT_TRIGGERED(sl) == 1) 1979 /* continue to check other slaves */ 1980 ret = 1; 1981 } 1982 } 1983 } 1984 show_result: 1985 return sprintf(buf, "%d\n", ret); 1986 } 1987 1988 static ssize_t conv_time_show(struct device *device, 1989 struct device_attribute *attr, char *buf) 1990 { 1991 struct w1_slave *sl = dev_to_w1_slave(device); 1992 1993 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 1994 dev_info(device, 1995 "%s: Device is not supported by the driver\n", __func__); 1996 return 0; /* No device family */ 1997 } 1998 return sprintf(buf, "%d\n", conversion_time(sl)); 1999 } 2000 2001 static ssize_t conv_time_store(struct device *device, 2002 struct device_attribute *attr, const char *buf, size_t size) 2003 { 2004 int val, ret = 0; 2005 struct w1_slave *sl = dev_to_w1_slave(device); 2006 2007 if (kstrtoint(buf, 10, &val)) /* converting user entry to int */ 2008 return -EINVAL; 2009 2010 if (check_family_data(sl)) 2011 return -ENODEV; 2012 2013 if (val != CONV_TIME_MEASURE) { 2014 if (val >= CONV_TIME_DEFAULT) 2015 SLAVE_CONV_TIME_OVERRIDE(sl) = val; 2016 else 2017 return -EINVAL; 2018 2019 } else { 2020 int conv_time; 2021 2022 ret = conv_time_measure(sl, &conv_time); 2023 if (ret) 2024 return -EIO; 2025 SLAVE_CONV_TIME_OVERRIDE(sl) = conv_time; 2026 } 2027 return size; 2028 } 2029 2030 static ssize_t features_show(struct device *device, 2031 struct device_attribute *attr, char *buf) 2032 { 2033 struct w1_slave *sl = dev_to_w1_slave(device); 2034 2035 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 2036 dev_info(device, 2037 "%s: Device not supported by the driver\n", __func__); 2038 return 0; /* No device family */ 2039 } 2040 return sprintf(buf, "%u\n", SLAVE_FEATURES(sl)); 2041 } 2042 2043 static ssize_t features_store(struct device *device, 2044 struct device_attribute *attr, const char *buf, size_t size) 2045 { 2046 int val, ret = 0; 2047 bool strong_pullup; 2048 struct w1_slave *sl = dev_to_w1_slave(device); 2049 2050 ret = kstrtouint(buf, 10, &val); /* converting user entry to int */ 2051 if (ret) 2052 return -EINVAL; /* invalid number */ 2053 2054 if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { 2055 dev_info(device, "%s: Device not supported by the driver\n", __func__); 2056 return -ENODEV; 2057 } 2058 2059 if ((val & W1_THERM_FEATURES_MASK) != val) 2060 return -EINVAL; 2061 2062 SLAVE_FEATURES(sl) = val; 2063 2064 strong_pullup = (w1_strong_pullup == 2 || 2065 (!SLAVE_POWERMODE(sl) && 2066 w1_strong_pullup)); 2067 2068 if (strong_pullup && SLAVE_FEATURES(sl) & W1_THERM_POLL_COMPLETION) { 2069 dev_warn(&sl->dev, 2070 "%s: W1_THERM_POLL_COMPLETION disabled in parasite power mode.\n", 2071 __func__); 2072 SLAVE_FEATURES(sl) &= ~W1_THERM_POLL_COMPLETION; 2073 } 2074 2075 return size; 2076 } 2077 2078 #if IS_REACHABLE(CONFIG_HWMON) 2079 static int w1_read_temp(struct device *device, u32 attr, int channel, 2080 long *val) 2081 { 2082 struct w1_slave *sl = dev_get_drvdata(device); 2083 struct therm_info info; 2084 int ret; 2085 2086 switch (attr) { 2087 case hwmon_temp_input: 2088 ret = convert_t(sl, &info); 2089 if (ret) 2090 return ret; 2091 2092 if (!info.verdict) { 2093 ret = -EIO; 2094 return ret; 2095 } 2096 2097 *val = temperature_from_RAM(sl, info.rom); 2098 ret = 0; 2099 break; 2100 default: 2101 ret = -EOPNOTSUPP; 2102 break; 2103 } 2104 2105 return ret; 2106 } 2107 #endif 2108 2109 #define W1_42_CHAIN 0x99 2110 #define W1_42_CHAIN_OFF 0x3C 2111 #define W1_42_CHAIN_OFF_INV 0xC3 2112 #define W1_42_CHAIN_ON 0x5A 2113 #define W1_42_CHAIN_ON_INV 0xA5 2114 #define W1_42_CHAIN_DONE 0x96 2115 #define W1_42_CHAIN_DONE_INV 0x69 2116 #define W1_42_COND_READ 0x0F 2117 #define W1_42_SUCCESS_CONFIRM_BYTE 0xAA 2118 #define W1_42_FINISHED_BYTE 0xFF 2119 static ssize_t w1_seq_show(struct device *device, 2120 struct device_attribute *attr, char *buf) 2121 { 2122 struct w1_slave *sl = dev_to_w1_slave(device); 2123 ssize_t c = PAGE_SIZE; 2124 int i; 2125 u8 ack; 2126 u64 rn; 2127 struct w1_reg_num *reg_num; 2128 int seq = 0; 2129 2130 mutex_lock(&sl->master->bus_mutex); 2131 /* Place all devices in CHAIN state */ 2132 if (w1_reset_bus(sl->master)) 2133 goto error; 2134 w1_write_8(sl->master, W1_SKIP_ROM); 2135 w1_write_8(sl->master, W1_42_CHAIN); 2136 w1_write_8(sl->master, W1_42_CHAIN_ON); 2137 w1_write_8(sl->master, W1_42_CHAIN_ON_INV); 2138 msleep(sl->master->pullup_duration); 2139 2140 /* check for acknowledgment */ 2141 ack = w1_read_8(sl->master); 2142 if (ack != W1_42_SUCCESS_CONFIRM_BYTE) 2143 goto error; 2144 2145 /* In case the bus fails to send 0xFF, limit */ 2146 for (i = 0; i <= 64; i++) { 2147 if (w1_reset_bus(sl->master)) 2148 goto error; 2149 2150 w1_write_8(sl->master, W1_42_COND_READ); 2151 w1_read_block(sl->master, (u8 *)&rn, 8); 2152 reg_num = (struct w1_reg_num *) &rn; 2153 if (reg_num->family == W1_42_FINISHED_BYTE) 2154 break; 2155 if (sl->reg_num.id == reg_num->id) 2156 seq = i; 2157 2158 if (w1_reset_bus(sl->master)) 2159 goto error; 2160 2161 /* Put the device into chain DONE state */ 2162 w1_write_8(sl->master, W1_MATCH_ROM); 2163 w1_write_block(sl->master, (u8 *)&rn, 8); 2164 w1_write_8(sl->master, W1_42_CHAIN); 2165 w1_write_8(sl->master, W1_42_CHAIN_DONE); 2166 w1_write_8(sl->master, W1_42_CHAIN_DONE_INV); 2167 2168 /* check for acknowledgment */ 2169 ack = w1_read_8(sl->master); 2170 if (ack != W1_42_SUCCESS_CONFIRM_BYTE) 2171 goto error; 2172 } 2173 2174 /* Exit from CHAIN state */ 2175 if (w1_reset_bus(sl->master)) 2176 goto error; 2177 w1_write_8(sl->master, W1_SKIP_ROM); 2178 w1_write_8(sl->master, W1_42_CHAIN); 2179 w1_write_8(sl->master, W1_42_CHAIN_OFF); 2180 w1_write_8(sl->master, W1_42_CHAIN_OFF_INV); 2181 2182 /* check for acknowledgment */ 2183 ack = w1_read_8(sl->master); 2184 if (ack != W1_42_SUCCESS_CONFIRM_BYTE) 2185 goto error; 2186 mutex_unlock(&sl->master->bus_mutex); 2187 2188 c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", seq); 2189 return PAGE_SIZE - c; 2190 error: 2191 mutex_unlock(&sl->master->bus_mutex); 2192 return -EIO; 2193 } 2194 2195 static int __init w1_therm_init(void) 2196 { 2197 int err, i; 2198 2199 for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) { 2200 err = w1_register_family(w1_therm_families[i].f); 2201 if (err) 2202 w1_therm_families[i].broken = 1; 2203 } 2204 2205 return 0; 2206 } 2207 2208 static void __exit w1_therm_fini(void) 2209 { 2210 int i; 2211 2212 for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) 2213 if (!w1_therm_families[i].broken) 2214 w1_unregister_family(w1_therm_families[i].f); 2215 } 2216 2217 module_init(w1_therm_init); 2218 module_exit(w1_therm_fini); 2219 2220 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); 2221 MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, temperature family."); 2222 MODULE_LICENSE("GPL"); 2223 MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18S20)); 2224 MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1822)); 2225 MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18B20)); 2226 MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1825)); 2227 MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS28EA00)); 2228