1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * g762 - Driver for the Global Mixed-mode Technology Inc. fan speed 4 * PWM controller chips from G762 family, i.e. G762 and G763 5 * 6 * Copyright (C) 2013, Arnaud EBALARD <arno@natisbad.org> 7 * 8 * This work is based on a basic version for 2.6.31 kernel developed 9 * by Olivier Mouchet for LaCie. Updates and correction have been 10 * performed to run on recent kernels. Additional features, like the 11 * ability to configure various characteristics via .dts file or 12 * board init file have been added. Detailed datasheet on which this 13 * development is based is available here: 14 * 15 * http://natisbad.org/NAS/refs/GMT_EDS-762_763-080710-0.2.pdf 16 * 17 * Headers from previous developments have been kept below: 18 * 19 * Copyright (c) 2009 LaCie 20 * 21 * Author: Olivier Mouchet <olivier.mouchet@gmail.com> 22 * 23 * based on g760a code written by Herbert Valerio Riedel <hvr@gnu.org> 24 * Copyright (C) 2007 Herbert Valerio Riedel <hvr@gnu.org> 25 * 26 * g762: minimal datasheet available at: 27 * http://www.gmt.com.tw/product/datasheet/EDS-762_3.pdf 28 */ 29 30#include <linux/device.h> 31#include <linux/module.h> 32#include <linux/init.h> 33#include <linux/jiffies.h> 34#include <linux/i2c.h> 35#include <linux/hwmon.h> 36#include <linux/hwmon-sysfs.h> 37#include <linux/err.h> 38#include <linux/mutex.h> 39#include <linux/kernel.h> 40#include <linux/clk.h> 41#include <linux/of.h> 42#include <linux/platform_data/g762.h> 43 44#define DRVNAME "g762" 45 46static const struct i2c_device_id g762_id[] = { 47 { "g762", 0 }, 48 { "g763", 0 }, 49 { } 50}; 51MODULE_DEVICE_TABLE(i2c, g762_id); 52 53enum g762_regs { 54 G762_REG_SET_CNT = 0x00, 55 G762_REG_ACT_CNT = 0x01, 56 G762_REG_FAN_STA = 0x02, 57 G762_REG_SET_OUT = 0x03, 58 G762_REG_FAN_CMD1 = 0x04, 59 G762_REG_FAN_CMD2 = 0x05, 60}; 61 62/* Config register bits */ 63#define G762_REG_FAN_CMD1_DET_FAN_FAIL 0x80 /* enable fan_fail signal */ 64#define G762_REG_FAN_CMD1_DET_FAN_OOC 0x40 /* enable fan_out_of_control */ 65#define G762_REG_FAN_CMD1_OUT_MODE 0x20 /* out mode: PWM or DC */ 66#define G762_REG_FAN_CMD1_FAN_MODE 0x10 /* fan mode: closed/open-loop */ 67#define G762_REG_FAN_CMD1_CLK_DIV_ID1 0x08 /* clock divisor value */ 68#define G762_REG_FAN_CMD1_CLK_DIV_ID0 0x04 69#define G762_REG_FAN_CMD1_PWM_POLARITY 0x02 /* PWM polarity */ 70#define G762_REG_FAN_CMD1_PULSE_PER_REV 0x01 /* pulse per fan revolution */ 71 72#define G762_REG_FAN_CMD2_GEAR_MODE_1 0x08 /* fan gear mode */ 73#define G762_REG_FAN_CMD2_GEAR_MODE_0 0x04 74#define G762_REG_FAN_CMD2_FAN_STARTV_1 0x02 /* fan startup voltage */ 75#define G762_REG_FAN_CMD2_FAN_STARTV_0 0x01 76 77#define G762_REG_FAN_STA_FAIL 0x02 /* fan fail */ 78#define G762_REG_FAN_STA_OOC 0x01 /* fan out of control */ 79 80/* Config register values */ 81#define G762_OUT_MODE_PWM 1 82#define G762_OUT_MODE_DC 0 83 84#define G762_FAN_MODE_CLOSED_LOOP 2 85#define G762_FAN_MODE_OPEN_LOOP 1 86 87#define G762_PWM_POLARITY_NEGATIVE 1 88#define G762_PWM_POLARITY_POSITIVE 0 89 90/* Register data is read (and cached) at most once per second. */ 91#define G762_UPDATE_INTERVAL HZ 92 93/* 94 * Extract pulse count per fan revolution value (2 or 4) from given 95 * FAN_CMD1 register value. 96 */ 97#define G762_PULSE_FROM_REG(reg) \ 98 ((((reg) & G762_REG_FAN_CMD1_PULSE_PER_REV) + 1) << 1) 99 100/* 101 * Extract fan clock divisor (1, 2, 4 or 8) from given FAN_CMD1 102 * register value. 103 */ 104#define G762_CLKDIV_FROM_REG(reg) \ 105 (1 << (((reg) & (G762_REG_FAN_CMD1_CLK_DIV_ID0 | \ 106 G762_REG_FAN_CMD1_CLK_DIV_ID1)) >> 2)) 107 108/* 109 * Extract fan gear mode multiplier value (0, 2 or 4) from given 110 * FAN_CMD2 register value. 111 */ 112#define G762_GEARMULT_FROM_REG(reg) \ 113 (1 << (((reg) & (G762_REG_FAN_CMD2_GEAR_MODE_0 | \ 114 G762_REG_FAN_CMD2_GEAR_MODE_1)) >> 2)) 115 116struct g762_data { 117 struct i2c_client *client; 118 struct clk *clk; 119 120 /* update mutex */ 121 struct mutex update_lock; 122 123 /* board specific parameters. */ 124 u32 clk_freq; 125 126 /* g762 register cache */ 127 bool valid; 128 unsigned long last_updated; /* in jiffies */ 129 130 u8 set_cnt; /* controls fan rotation speed in closed-loop mode */ 131 u8 act_cnt; /* provides access to current fan RPM value */ 132 u8 fan_sta; /* bit 0: set when actual fan speed is more than 133 * 25% outside requested fan speed 134 * bit 1: set when no transition occurs on fan 135 * pin for 0.7s 136 */ 137 u8 set_out; /* controls fan rotation speed in open-loop mode */ 138 u8 fan_cmd1; /* 0: FG_PLS_ID0 FG pulses count per revolution 139 * 0: 2 counts per revolution 140 * 1: 4 counts per revolution 141 * 1: PWM_POLARITY 1: negative_duty 142 * 0: positive_duty 143 * 2,3: [FG_CLOCK_ID0, FG_CLK_ID1] 144 * 00: Divide fan clock by 1 145 * 01: Divide fan clock by 2 146 * 10: Divide fan clock by 4 147 * 11: Divide fan clock by 8 148 * 4: FAN_MODE 1:closed-loop, 0:open-loop 149 * 5: OUT_MODE 1:PWM, 0:DC 150 * 6: DET_FAN_OOC enable "fan ooc" status 151 * 7: DET_FAN_FAIL enable "fan fail" status 152 */ 153 u8 fan_cmd2; /* 0,1: FAN_STARTV 0,1,2,3 -> 0,32,64,96 dac_code 154 * 2,3: FG_GEAR_MODE 155 * 00: multiplier = 1 156 * 01: multiplier = 2 157 * 10: multiplier = 4 158 * 4: Mask ALERT# (g763 only) 159 */ 160}; 161 162/* 163 * Convert count value from fan controller register (FAN_SET_CNT) into fan 164 * speed RPM value. Note that the datasheet documents a basic formula; 165 * influence of additional parameters (fan clock divisor, fan gear mode) 166 * have been infered from examples in the datasheet and tests. 167 */ 168static inline unsigned int rpm_from_cnt(u8 cnt, u32 clk_freq, u16 p, 169 u8 clk_div, u8 gear_mult) 170{ 171 if (cnt == 0xff) /* setting cnt to 255 stops the fan */ 172 return 0; 173 174 return (clk_freq * 30 * gear_mult) / ((cnt ? cnt : 1) * p * clk_div); 175} 176 177/* 178 * Convert fan RPM value from sysfs into count value for fan controller 179 * register (FAN_SET_CNT). 180 */ 181static inline unsigned char cnt_from_rpm(unsigned long rpm, u32 clk_freq, u16 p, 182 u8 clk_div, u8 gear_mult) 183{ 184 unsigned long f1 = clk_freq * 30 * gear_mult; 185 unsigned long f2 = p * clk_div; 186 187 if (!rpm) /* to stop the fan, set cnt to 255 */ 188 return 0xff; 189 190 rpm = clamp_val(rpm, f1 / (255 * f2), ULONG_MAX / f2); 191 return DIV_ROUND_CLOSEST(f1, rpm * f2); 192} 193 194/* helper to grab and cache data, at most one time per second */ 195static struct g762_data *g762_update_client(struct device *dev) 196{ 197 struct g762_data *data = dev_get_drvdata(dev); 198 struct i2c_client *client = data->client; 199 int ret = 0; 200 201 mutex_lock(&data->update_lock); 202 if (time_before(jiffies, data->last_updated + G762_UPDATE_INTERVAL) && 203 likely(data->valid)) 204 goto out; 205 206 ret = i2c_smbus_read_byte_data(client, G762_REG_SET_CNT); 207 if (ret < 0) 208 goto out; 209 data->set_cnt = ret; 210 211 ret = i2c_smbus_read_byte_data(client, G762_REG_ACT_CNT); 212 if (ret < 0) 213 goto out; 214 data->act_cnt = ret; 215 216 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_STA); 217 if (ret < 0) 218 goto out; 219 data->fan_sta = ret; 220 221 ret = i2c_smbus_read_byte_data(client, G762_REG_SET_OUT); 222 if (ret < 0) 223 goto out; 224 data->set_out = ret; 225 226 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD1); 227 if (ret < 0) 228 goto out; 229 data->fan_cmd1 = ret; 230 231 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD2); 232 if (ret < 0) 233 goto out; 234 data->fan_cmd2 = ret; 235 236 data->last_updated = jiffies; 237 data->valid = true; 238 out: 239 mutex_unlock(&data->update_lock); 240 241 if (ret < 0) /* upon error, encode it in return value */ 242 data = ERR_PTR(ret); 243 244 return data; 245} 246 247/* helpers for writing hardware parameters */ 248 249/* 250 * Set input clock frequency received on CLK pin of the chip. Accepted values 251 * are between 0 and 0xffffff. If zero is given, then default frequency 252 * (32,768Hz) is used. Note that clock frequency is a characteristic of the 253 * system but an internal parameter, i.e. value is not passed to the device. 254 */ 255static int do_set_clk_freq(struct device *dev, unsigned long val) 256{ 257 struct g762_data *data = dev_get_drvdata(dev); 258 259 if (val > 0xffffff) 260 return -EINVAL; 261 if (!val) 262 val = 32768; 263 264 data->clk_freq = val; 265 266 return 0; 267} 268 269/* Set pwm mode. Accepts either 0 (PWM mode) or 1 (DC mode) */ 270static int do_set_pwm_mode(struct device *dev, unsigned long val) 271{ 272 struct g762_data *data = g762_update_client(dev); 273 int ret; 274 275 if (IS_ERR(data)) 276 return PTR_ERR(data); 277 278 mutex_lock(&data->update_lock); 279 switch (val) { 280 case G762_OUT_MODE_PWM: 281 data->fan_cmd1 |= G762_REG_FAN_CMD1_OUT_MODE; 282 break; 283 case G762_OUT_MODE_DC: 284 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_OUT_MODE; 285 break; 286 default: 287 ret = -EINVAL; 288 goto out; 289 } 290 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 291 data->fan_cmd1); 292 data->valid = false; 293 out: 294 mutex_unlock(&data->update_lock); 295 296 return ret; 297} 298 299/* Set fan clock divisor. Accepts either 1, 2, 4 or 8. */ 300static int do_set_fan_div(struct device *dev, unsigned long val) 301{ 302 struct g762_data *data = g762_update_client(dev); 303 int ret; 304 305 if (IS_ERR(data)) 306 return PTR_ERR(data); 307 308 mutex_lock(&data->update_lock); 309 switch (val) { 310 case 1: 311 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0; 312 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1; 313 break; 314 case 2: 315 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; 316 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1; 317 break; 318 case 4: 319 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0; 320 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; 321 break; 322 case 8: 323 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; 324 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; 325 break; 326 default: 327 ret = -EINVAL; 328 goto out; 329 } 330 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 331 data->fan_cmd1); 332 data->valid = false; 333 out: 334 mutex_unlock(&data->update_lock); 335 336 return ret; 337} 338 339/* Set fan gear mode. Accepts either 0, 1 or 2. */ 340static int do_set_fan_gear_mode(struct device *dev, unsigned long val) 341{ 342 struct g762_data *data = g762_update_client(dev); 343 int ret; 344 345 if (IS_ERR(data)) 346 return PTR_ERR(data); 347 348 mutex_lock(&data->update_lock); 349 switch (val) { 350 case 0: 351 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; 352 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; 353 break; 354 case 1: 355 data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_0; 356 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; 357 break; 358 case 2: 359 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; 360 data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_1; 361 break; 362 default: 363 ret = -EINVAL; 364 goto out; 365 } 366 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2, 367 data->fan_cmd2); 368 data->valid = false; 369 out: 370 mutex_unlock(&data->update_lock); 371 372 return ret; 373} 374 375/* Set number of fan pulses per revolution. Accepts either 2 or 4. */ 376static int do_set_fan_pulses(struct device *dev, unsigned long val) 377{ 378 struct g762_data *data = g762_update_client(dev); 379 int ret; 380 381 if (IS_ERR(data)) 382 return PTR_ERR(data); 383 384 mutex_lock(&data->update_lock); 385 switch (val) { 386 case 2: 387 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PULSE_PER_REV; 388 break; 389 case 4: 390 data->fan_cmd1 |= G762_REG_FAN_CMD1_PULSE_PER_REV; 391 break; 392 default: 393 ret = -EINVAL; 394 goto out; 395 } 396 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 397 data->fan_cmd1); 398 data->valid = false; 399 out: 400 mutex_unlock(&data->update_lock); 401 402 return ret; 403} 404 405/* Set fan mode. Accepts either 1 (open-loop) or 2 (closed-loop). */ 406static int do_set_pwm_enable(struct device *dev, unsigned long val) 407{ 408 struct g762_data *data = g762_update_client(dev); 409 int ret; 410 411 if (IS_ERR(data)) 412 return PTR_ERR(data); 413 414 mutex_lock(&data->update_lock); 415 switch (val) { 416 case G762_FAN_MODE_CLOSED_LOOP: 417 data->fan_cmd1 |= G762_REG_FAN_CMD1_FAN_MODE; 418 break; 419 case G762_FAN_MODE_OPEN_LOOP: 420 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_FAN_MODE; 421 /* 422 * BUG FIX: if SET_CNT register value is 255 then, for some 423 * unknown reason, fan will not rotate as expected, no matter 424 * the value of SET_OUT (to be specific, this seems to happen 425 * only in PWM mode). To workaround this bug, we give SET_CNT 426 * value of 254 if it is 255 when switching to open-loop. 427 */ 428 if (data->set_cnt == 0xff) 429 i2c_smbus_write_byte_data(data->client, 430 G762_REG_SET_CNT, 254); 431 break; 432 default: 433 ret = -EINVAL; 434 goto out; 435 } 436 437 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 438 data->fan_cmd1); 439 data->valid = false; 440 out: 441 mutex_unlock(&data->update_lock); 442 443 return ret; 444} 445 446/* Set PWM polarity. Accepts either 0 (positive duty) or 1 (negative duty) */ 447static int do_set_pwm_polarity(struct device *dev, unsigned long val) 448{ 449 struct g762_data *data = g762_update_client(dev); 450 int ret; 451 452 if (IS_ERR(data)) 453 return PTR_ERR(data); 454 455 mutex_lock(&data->update_lock); 456 switch (val) { 457 case G762_PWM_POLARITY_POSITIVE: 458 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PWM_POLARITY; 459 break; 460 case G762_PWM_POLARITY_NEGATIVE: 461 data->fan_cmd1 |= G762_REG_FAN_CMD1_PWM_POLARITY; 462 break; 463 default: 464 ret = -EINVAL; 465 goto out; 466 } 467 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 468 data->fan_cmd1); 469 data->valid = false; 470 out: 471 mutex_unlock(&data->update_lock); 472 473 return ret; 474} 475 476/* 477 * Set pwm value. Accepts values between 0 (stops the fan) and 478 * 255 (full speed). This only makes sense in open-loop mode. 479 */ 480static int do_set_pwm(struct device *dev, unsigned long val) 481{ 482 struct g762_data *data = dev_get_drvdata(dev); 483 struct i2c_client *client = data->client; 484 int ret; 485 486 if (val > 255) 487 return -EINVAL; 488 489 mutex_lock(&data->update_lock); 490 ret = i2c_smbus_write_byte_data(client, G762_REG_SET_OUT, val); 491 data->valid = false; 492 mutex_unlock(&data->update_lock); 493 494 return ret; 495} 496 497/* 498 * Set fan RPM value. Can be called both in closed and open-loop mode 499 * but effect will only be seen after closed-loop mode is configured. 500 */ 501static int do_set_fan_target(struct device *dev, unsigned long val) 502{ 503 struct g762_data *data = g762_update_client(dev); 504 int ret; 505 506 if (IS_ERR(data)) 507 return PTR_ERR(data); 508 509 mutex_lock(&data->update_lock); 510 data->set_cnt = cnt_from_rpm(val, data->clk_freq, 511 G762_PULSE_FROM_REG(data->fan_cmd1), 512 G762_CLKDIV_FROM_REG(data->fan_cmd1), 513 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 514 ret = i2c_smbus_write_byte_data(data->client, G762_REG_SET_CNT, 515 data->set_cnt); 516 data->valid = false; 517 mutex_unlock(&data->update_lock); 518 519 return ret; 520} 521 522/* Set fan startup voltage. Accepted values are either 0, 1, 2 or 3. */ 523static int do_set_fan_startv(struct device *dev, unsigned long val) 524{ 525 struct g762_data *data = g762_update_client(dev); 526 int ret; 527 528 if (IS_ERR(data)) 529 return PTR_ERR(data); 530 531 mutex_lock(&data->update_lock); 532 switch (val) { 533 case 0: 534 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0; 535 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1; 536 break; 537 case 1: 538 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; 539 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1; 540 break; 541 case 2: 542 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0; 543 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; 544 break; 545 case 3: 546 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; 547 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; 548 break; 549 default: 550 ret = -EINVAL; 551 goto out; 552 } 553 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2, 554 data->fan_cmd2); 555 data->valid = false; 556 out: 557 mutex_unlock(&data->update_lock); 558 559 return ret; 560} 561 562/* 563 * Helper to import hardware characteristics from .dts file and push 564 * those to the chip. 565 */ 566 567#ifdef CONFIG_OF 568static const struct of_device_id g762_dt_match[] = { 569 { .compatible = "gmt,g762" }, 570 { .compatible = "gmt,g763" }, 571 { }, 572}; 573MODULE_DEVICE_TABLE(of, g762_dt_match); 574 575/* 576 * Grab clock (a required property), enable it, get (fixed) clock frequency 577 * and store it. Note: upon success, clock has been prepared and enabled; it 578 * must later be unprepared and disabled (e.g. during module unloading) by a 579 * call to g762_of_clock_disable(). Note that a reference to clock is kept 580 * in our private data structure to be used in this function. 581 */ 582static void g762_of_clock_disable(void *data) 583{ 584 struct g762_data *g762 = data; 585 586 clk_disable_unprepare(g762->clk); 587 clk_put(g762->clk); 588} 589 590static int g762_of_clock_enable(struct i2c_client *client) 591{ 592 struct g762_data *data; 593 unsigned long clk_freq; 594 struct clk *clk; 595 int ret; 596 597 if (!client->dev.of_node) 598 return 0; 599 600 clk = of_clk_get(client->dev.of_node, 0); 601 if (IS_ERR(clk)) { 602 dev_err(&client->dev, "failed to get clock\n"); 603 return PTR_ERR(clk); 604 } 605 606 ret = clk_prepare_enable(clk); 607 if (ret) { 608 dev_err(&client->dev, "failed to enable clock\n"); 609 goto clk_put; 610 } 611 612 clk_freq = clk_get_rate(clk); 613 ret = do_set_clk_freq(&client->dev, clk_freq); 614 if (ret) { 615 dev_err(&client->dev, "invalid clock freq %lu\n", clk_freq); 616 goto clk_unprep; 617 } 618 619 data = i2c_get_clientdata(client); 620 data->clk = clk; 621 622 ret = devm_add_action(&client->dev, g762_of_clock_disable, data); 623 if (ret) { 624 dev_err(&client->dev, "failed to add disable clock action\n"); 625 goto clk_unprep; 626 } 627 628 return 0; 629 630 clk_unprep: 631 clk_disable_unprepare(clk); 632 633 clk_put: 634 clk_put(clk); 635 636 return ret; 637} 638 639static int g762_of_prop_import_one(struct i2c_client *client, 640 const char *pname, 641 int (*psetter)(struct device *dev, 642 unsigned long val)) 643{ 644 int ret; 645 u32 pval; 646 647 if (of_property_read_u32(client->dev.of_node, pname, &pval)) 648 return 0; 649 650 dev_dbg(&client->dev, "found %s (%d)\n", pname, pval); 651 ret = (*psetter)(&client->dev, pval); 652 if (ret) 653 dev_err(&client->dev, "unable to set %s (%d)\n", pname, pval); 654 655 return ret; 656} 657 658static int g762_of_prop_import(struct i2c_client *client) 659{ 660 int ret; 661 662 if (!client->dev.of_node) 663 return 0; 664 665 ret = g762_of_prop_import_one(client, "fan_gear_mode", 666 do_set_fan_gear_mode); 667 if (ret) 668 return ret; 669 670 ret = g762_of_prop_import_one(client, "pwm_polarity", 671 do_set_pwm_polarity); 672 if (ret) 673 return ret; 674 675 return g762_of_prop_import_one(client, "fan_startv", 676 do_set_fan_startv); 677} 678 679#else 680static int g762_of_prop_import(struct i2c_client *client) 681{ 682 return 0; 683} 684 685static int g762_of_clock_enable(struct i2c_client *client) 686{ 687 return 0; 688} 689#endif 690 691/* 692 * Helper to import hardware characteristics from .dts file and push 693 * those to the chip. 694 */ 695 696static int g762_pdata_prop_import(struct i2c_client *client) 697{ 698 struct g762_platform_data *pdata = dev_get_platdata(&client->dev); 699 int ret; 700 701 if (!pdata) 702 return 0; 703 704 ret = do_set_fan_gear_mode(&client->dev, pdata->fan_gear_mode); 705 if (ret) 706 return ret; 707 708 ret = do_set_pwm_polarity(&client->dev, pdata->pwm_polarity); 709 if (ret) 710 return ret; 711 712 ret = do_set_fan_startv(&client->dev, pdata->fan_startv); 713 if (ret) 714 return ret; 715 716 return do_set_clk_freq(&client->dev, pdata->clk_freq); 717} 718 719/* 720 * sysfs attributes 721 */ 722 723/* 724 * Read function for fan1_input sysfs file. Return current fan RPM value, or 725 * 0 if fan is out of control. 726 */ 727static ssize_t fan1_input_show(struct device *dev, 728 struct device_attribute *da, char *buf) 729{ 730 struct g762_data *data = g762_update_client(dev); 731 unsigned int rpm = 0; 732 733 if (IS_ERR(data)) 734 return PTR_ERR(data); 735 736 mutex_lock(&data->update_lock); 737 /* reverse logic: fan out of control reporting is enabled low */ 738 if (data->fan_sta & G762_REG_FAN_STA_OOC) { 739 rpm = rpm_from_cnt(data->act_cnt, data->clk_freq, 740 G762_PULSE_FROM_REG(data->fan_cmd1), 741 G762_CLKDIV_FROM_REG(data->fan_cmd1), 742 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 743 } 744 mutex_unlock(&data->update_lock); 745 746 return sprintf(buf, "%u\n", rpm); 747} 748 749/* 750 * Read and write functions for pwm1_mode sysfs file. Get and set fan speed 751 * control mode i.e. PWM (1) or DC (0). 752 */ 753static ssize_t pwm1_mode_show(struct device *dev, struct device_attribute *da, 754 char *buf) 755{ 756 struct g762_data *data = g762_update_client(dev); 757 758 if (IS_ERR(data)) 759 return PTR_ERR(data); 760 761 return sprintf(buf, "%d\n", 762 !!(data->fan_cmd1 & G762_REG_FAN_CMD1_OUT_MODE)); 763} 764 765static ssize_t pwm1_mode_store(struct device *dev, 766 struct device_attribute *da, const char *buf, 767 size_t count) 768{ 769 unsigned long val; 770 int ret; 771 772 if (kstrtoul(buf, 10, &val)) 773 return -EINVAL; 774 775 ret = do_set_pwm_mode(dev, val); 776 if (ret < 0) 777 return ret; 778 779 return count; 780} 781 782/* 783 * Read and write functions for fan1_div sysfs file. Get and set fan 784 * controller prescaler value 785 */ 786static ssize_t fan1_div_show(struct device *dev, struct device_attribute *da, 787 char *buf) 788{ 789 struct g762_data *data = g762_update_client(dev); 790 791 if (IS_ERR(data)) 792 return PTR_ERR(data); 793 794 return sprintf(buf, "%d\n", G762_CLKDIV_FROM_REG(data->fan_cmd1)); 795} 796 797static ssize_t fan1_div_store(struct device *dev, struct device_attribute *da, 798 const char *buf, size_t count) 799{ 800 unsigned long val; 801 int ret; 802 803 if (kstrtoul(buf, 10, &val)) 804 return -EINVAL; 805 806 ret = do_set_fan_div(dev, val); 807 if (ret < 0) 808 return ret; 809 810 return count; 811} 812 813/* 814 * Read and write functions for fan1_pulses sysfs file. Get and set number 815 * of tachometer pulses per fan revolution. 816 */ 817static ssize_t fan1_pulses_show(struct device *dev, 818 struct device_attribute *da, char *buf) 819{ 820 struct g762_data *data = g762_update_client(dev); 821 822 if (IS_ERR(data)) 823 return PTR_ERR(data); 824 825 return sprintf(buf, "%d\n", G762_PULSE_FROM_REG(data->fan_cmd1)); 826} 827 828static ssize_t fan1_pulses_store(struct device *dev, 829 struct device_attribute *da, const char *buf, 830 size_t count) 831{ 832 unsigned long val; 833 int ret; 834 835 if (kstrtoul(buf, 10, &val)) 836 return -EINVAL; 837 838 ret = do_set_fan_pulses(dev, val); 839 if (ret < 0) 840 return ret; 841 842 return count; 843} 844 845/* 846 * Read and write functions for pwm1_enable. Get and set fan speed control mode 847 * (i.e. closed or open-loop). 848 * 849 * Following documentation about hwmon's sysfs interface, a pwm1_enable node 850 * should accept the following: 851 * 852 * 0 : no fan speed control (i.e. fan at full speed) 853 * 1 : manual fan speed control enabled (use pwm[1-*]) (open-loop) 854 * 2+: automatic fan speed control enabled (use fan[1-*]_target) (closed-loop) 855 * 856 * but we do not accept 0 as this mode is not natively supported by the chip 857 * and it is not emulated by g762 driver. -EINVAL is returned in this case. 858 */ 859static ssize_t pwm1_enable_show(struct device *dev, 860 struct device_attribute *da, char *buf) 861{ 862 struct g762_data *data = g762_update_client(dev); 863 864 if (IS_ERR(data)) 865 return PTR_ERR(data); 866 867 return sprintf(buf, "%d\n", 868 (!!(data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE)) + 1); 869} 870 871static ssize_t pwm1_enable_store(struct device *dev, 872 struct device_attribute *da, const char *buf, 873 size_t count) 874{ 875 unsigned long val; 876 int ret; 877 878 if (kstrtoul(buf, 10, &val)) 879 return -EINVAL; 880 881 ret = do_set_pwm_enable(dev, val); 882 if (ret < 0) 883 return ret; 884 885 return count; 886} 887 888/* 889 * Read and write functions for pwm1 sysfs file. Get and set pwm value 890 * (which affects fan speed) in open-loop mode. 0 stops the fan and 255 891 * makes it run at full speed. 892 */ 893static ssize_t pwm1_show(struct device *dev, struct device_attribute *da, 894 char *buf) 895{ 896 struct g762_data *data = g762_update_client(dev); 897 898 if (IS_ERR(data)) 899 return PTR_ERR(data); 900 901 return sprintf(buf, "%d\n", data->set_out); 902} 903 904static ssize_t pwm1_store(struct device *dev, struct device_attribute *da, 905 const char *buf, size_t count) 906{ 907 unsigned long val; 908 int ret; 909 910 if (kstrtoul(buf, 10, &val)) 911 return -EINVAL; 912 913 ret = do_set_pwm(dev, val); 914 if (ret < 0) 915 return ret; 916 917 return count; 918} 919 920/* 921 * Read and write function for fan1_target sysfs file. Get/set the fan speed in 922 * closed-loop mode. Speed is given as a RPM value; then the chip will regulate 923 * the fan speed using pulses from fan tachometer. 924 * 925 * Refer to rpm_from_cnt() implementation above to get info about count number 926 * calculation. 927 * 928 * Also note that due to rounding errors it is possible that you don't read 929 * back exactly the value you have set. 930 */ 931static ssize_t fan1_target_show(struct device *dev, 932 struct device_attribute *da, char *buf) 933{ 934 struct g762_data *data = g762_update_client(dev); 935 unsigned int rpm; 936 937 if (IS_ERR(data)) 938 return PTR_ERR(data); 939 940 mutex_lock(&data->update_lock); 941 rpm = rpm_from_cnt(data->set_cnt, data->clk_freq, 942 G762_PULSE_FROM_REG(data->fan_cmd1), 943 G762_CLKDIV_FROM_REG(data->fan_cmd1), 944 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 945 mutex_unlock(&data->update_lock); 946 947 return sprintf(buf, "%u\n", rpm); 948} 949 950static ssize_t fan1_target_store(struct device *dev, 951 struct device_attribute *da, const char *buf, 952 size_t count) 953{ 954 unsigned long val; 955 int ret; 956 957 if (kstrtoul(buf, 10, &val)) 958 return -EINVAL; 959 960 ret = do_set_fan_target(dev, val); 961 if (ret < 0) 962 return ret; 963 964 return count; 965} 966 967/* read function for fan1_fault sysfs file. */ 968static ssize_t fan1_fault_show(struct device *dev, struct device_attribute *da, 969 char *buf) 970{ 971 struct g762_data *data = g762_update_client(dev); 972 973 if (IS_ERR(data)) 974 return PTR_ERR(data); 975 976 return sprintf(buf, "%u\n", !!(data->fan_sta & G762_REG_FAN_STA_FAIL)); 977} 978 979/* 980 * read function for fan1_alarm sysfs file. Note that OOC condition is 981 * enabled low 982 */ 983static ssize_t fan1_alarm_show(struct device *dev, 984 struct device_attribute *da, char *buf) 985{ 986 struct g762_data *data = g762_update_client(dev); 987 988 if (IS_ERR(data)) 989 return PTR_ERR(data); 990 991 return sprintf(buf, "%u\n", !(data->fan_sta & G762_REG_FAN_STA_OOC)); 992} 993 994static DEVICE_ATTR_RW(pwm1); 995static DEVICE_ATTR_RW(pwm1_mode); 996static DEVICE_ATTR_RW(pwm1_enable); 997static DEVICE_ATTR_RO(fan1_input); 998static DEVICE_ATTR_RO(fan1_alarm); 999static DEVICE_ATTR_RO(fan1_fault); 1000static DEVICE_ATTR_RW(fan1_target); 1001static DEVICE_ATTR_RW(fan1_div); 1002static DEVICE_ATTR_RW(fan1_pulses); 1003 1004/* Driver data */ 1005static struct attribute *g762_attrs[] = { 1006 &dev_attr_fan1_input.attr, 1007 &dev_attr_fan1_alarm.attr, 1008 &dev_attr_fan1_fault.attr, 1009 &dev_attr_fan1_target.attr, 1010 &dev_attr_fan1_div.attr, 1011 &dev_attr_fan1_pulses.attr, 1012 &dev_attr_pwm1.attr, 1013 &dev_attr_pwm1_mode.attr, 1014 &dev_attr_pwm1_enable.attr, 1015 NULL 1016}; 1017 1018ATTRIBUTE_GROUPS(g762); 1019 1020/* 1021 * Enable both fan failure detection and fan out of control protection. The 1022 * function does not protect change/access to data structure; it must thus 1023 * only be called during initialization. 1024 */ 1025static inline int g762_fan_init(struct device *dev) 1026{ 1027 struct g762_data *data = g762_update_client(dev); 1028 1029 if (IS_ERR(data)) 1030 return PTR_ERR(data); 1031 1032 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL; 1033 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC; 1034 data->valid = false; 1035 1036 return i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 1037 data->fan_cmd1); 1038} 1039 1040static int g762_probe(struct i2c_client *client) 1041{ 1042 struct device *dev = &client->dev; 1043 struct device *hwmon_dev; 1044 struct g762_data *data; 1045 int ret; 1046 1047 if (!i2c_check_functionality(client->adapter, 1048 I2C_FUNC_SMBUS_BYTE_DATA)) 1049 return -ENODEV; 1050 1051 data = devm_kzalloc(dev, sizeof(struct g762_data), GFP_KERNEL); 1052 if (!data) 1053 return -ENOMEM; 1054 1055 i2c_set_clientdata(client, data); 1056 data->client = client; 1057 mutex_init(&data->update_lock); 1058 1059 /* Enable fan failure detection and fan out of control protection */ 1060 ret = g762_fan_init(dev); 1061 if (ret) 1062 return ret; 1063 1064 /* Get configuration via DT ... */ 1065 ret = g762_of_clock_enable(client); 1066 if (ret) 1067 return ret; 1068 ret = g762_of_prop_import(client); 1069 if (ret) 1070 return ret; 1071 /* ... or platform_data */ 1072 ret = g762_pdata_prop_import(client); 1073 if (ret) 1074 return ret; 1075 1076 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, 1077 data, g762_groups); 1078 return PTR_ERR_OR_ZERO(hwmon_dev); 1079} 1080 1081static struct i2c_driver g762_driver = { 1082 .driver = { 1083 .name = DRVNAME, 1084 .of_match_table = of_match_ptr(g762_dt_match), 1085 }, 1086 .probe = g762_probe, 1087 .id_table = g762_id, 1088}; 1089 1090module_i2c_driver(g762_driver); 1091 1092MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>"); 1093MODULE_DESCRIPTION("GMT G762/G763 driver"); 1094MODULE_LICENSE("GPL"); 1095