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