1 /* 2 * g762 - Driver for the Global Mixed-mode Technology Inc. fan speed 3 * PWM controller chips from G762 family, i.e. G762 and G763 4 * 5 * Copyright (C) 2013, Arnaud EBALARD <arno@natisbad.org> 6 * 7 * This work is based on a basic version for 2.6.31 kernel developed 8 * by Olivier Mouchet for LaCie. Updates and correction have been 9 * performed to run on recent kernels. Additional features, like the 10 * ability to configure various characteristics via .dts file or 11 * board init file have been added. Detailed datasheet on which this 12 * development is based is available here: 13 * 14 * http://natisbad.org/NAS/refs/GMT_EDS-762_763-080710-0.2.pdf 15 * 16 * Headers from previous developments have been kept below: 17 * 18 * Copyright (c) 2009 LaCie 19 * 20 * Author: Olivier Mouchet <olivier.mouchet@gmail.com> 21 * 22 * based on g760a code written by Herbert Valerio Riedel <hvr@gnu.org> 23 * Copyright (C) 2007 Herbert Valerio Riedel <hvr@gnu.org> 24 * 25 * g762: minimal datasheet available at: 26 * http://www.gmt.com.tw/product/datasheet/EDS-762_3.pdf 27 * 28 * This program is free software; you can redistribute it and/or modify 29 * it under the terms of the GNU General Public License as published by 30 * the Free Software Foundation; either version 2 of the License, or 31 * (at your option) any later version. 32 * 33 * This program is distributed in the hope that it will be useful, 34 * but WITHOUT ANY WARRANTY; without even the implied warranty of 35 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 36 * GNU General Public License for more details. 37 * 38 * You should have received a copy of the GNU General Public License 39 * along with this program; if not, write to the Free Software 40 * Foundation. 41 */ 42 43 #include <linux/device.h> 44 #include <linux/module.h> 45 #include <linux/init.h> 46 #include <linux/jiffies.h> 47 #include <linux/i2c.h> 48 #include <linux/hwmon.h> 49 #include <linux/hwmon-sysfs.h> 50 #include <linux/err.h> 51 #include <linux/mutex.h> 52 #include <linux/kernel.h> 53 #include <linux/clk.h> 54 #include <linux/of.h> 55 #include <linux/of_device.h> 56 #include <linux/platform_data/g762.h> 57 58 #define DRVNAME "g762" 59 60 static const struct i2c_device_id g762_id[] = { 61 { "g762", 0 }, 62 { "g763", 0 }, 63 { } 64 }; 65 MODULE_DEVICE_TABLE(i2c, g762_id); 66 67 enum g762_regs { 68 G762_REG_SET_CNT = 0x00, 69 G762_REG_ACT_CNT = 0x01, 70 G762_REG_FAN_STA = 0x02, 71 G762_REG_SET_OUT = 0x03, 72 G762_REG_FAN_CMD1 = 0x04, 73 G762_REG_FAN_CMD2 = 0x05, 74 }; 75 76 /* Config register bits */ 77 #define G762_REG_FAN_CMD1_DET_FAN_FAIL 0x80 /* enable fan_fail signal */ 78 #define G762_REG_FAN_CMD1_DET_FAN_OOC 0x40 /* enable fan_out_of_control */ 79 #define G762_REG_FAN_CMD1_OUT_MODE 0x20 /* out mode: PWM or DC */ 80 #define G762_REG_FAN_CMD1_FAN_MODE 0x10 /* fan mode: closed/open-loop */ 81 #define G762_REG_FAN_CMD1_CLK_DIV_ID1 0x08 /* clock divisor value */ 82 #define G762_REG_FAN_CMD1_CLK_DIV_ID0 0x04 83 #define G762_REG_FAN_CMD1_PWM_POLARITY 0x02 /* PWM polarity */ 84 #define G762_REG_FAN_CMD1_PULSE_PER_REV 0x01 /* pulse per fan revolution */ 85 86 #define G762_REG_FAN_CMD2_GEAR_MODE_1 0x08 /* fan gear mode */ 87 #define G762_REG_FAN_CMD2_GEAR_MODE_0 0x04 88 #define G762_REG_FAN_CMD2_FAN_STARTV_1 0x02 /* fan startup voltage */ 89 #define G762_REG_FAN_CMD2_FAN_STARTV_0 0x01 90 91 #define G762_REG_FAN_STA_FAIL 0x02 /* fan fail */ 92 #define G762_REG_FAN_STA_OOC 0x01 /* fan out of control */ 93 94 /* Config register values */ 95 #define G762_OUT_MODE_PWM 1 96 #define G762_OUT_MODE_DC 0 97 98 #define G762_FAN_MODE_CLOSED_LOOP 2 99 #define G762_FAN_MODE_OPEN_LOOP 1 100 101 #define G762_PWM_POLARITY_NEGATIVE 1 102 #define G762_PWM_POLARITY_POSITIVE 0 103 104 /* Register data is read (and cached) at most once per second. */ 105 #define G762_UPDATE_INTERVAL HZ 106 107 /* 108 * Extract pulse count per fan revolution value (2 or 4) from given 109 * FAN_CMD1 register value. 110 */ 111 #define G762_PULSE_FROM_REG(reg) \ 112 ((((reg) & G762_REG_FAN_CMD1_PULSE_PER_REV) + 1) << 1) 113 114 /* 115 * Extract fan clock divisor (1, 2, 4 or 8) from given FAN_CMD1 116 * register value. 117 */ 118 #define G762_CLKDIV_FROM_REG(reg) \ 119 (1 << (((reg) & (G762_REG_FAN_CMD1_CLK_DIV_ID0 | \ 120 G762_REG_FAN_CMD1_CLK_DIV_ID1)) >> 2)) 121 122 /* 123 * Extract fan gear mode multiplier value (0, 2 or 4) from given 124 * FAN_CMD2 register value. 125 */ 126 #define G762_GEARMULT_FROM_REG(reg) \ 127 (1 << (((reg) & (G762_REG_FAN_CMD2_GEAR_MODE_0 | \ 128 G762_REG_FAN_CMD2_GEAR_MODE_1)) >> 2)) 129 130 struct g762_data { 131 struct device *hwmon_dev; 132 struct i2c_client *client; 133 struct clk *clk; 134 135 /* update mutex */ 136 struct mutex update_lock; 137 138 /* board specific parameters. */ 139 u32 clk_freq; 140 141 /* g762 register cache */ 142 bool valid; 143 unsigned long last_updated; /* in jiffies */ 144 145 u8 set_cnt; /* controls fan rotation speed in closed-loop mode */ 146 u8 act_cnt; /* provides access to current fan RPM value */ 147 u8 fan_sta; /* bit 0: set when actual fan speed is more than 148 * 25% outside requested fan speed 149 * bit 1: set when no transition occurs on fan 150 * pin for 0.7s 151 */ 152 u8 set_out; /* controls fan rotation speed in open-loop mode */ 153 u8 fan_cmd1; /* 0: FG_PLS_ID0 FG pulses count per revolution 154 * 0: 2 counts per revolution 155 * 1: 4 counts per revolution 156 * 1: PWM_POLARITY 1: negative_duty 157 * 0: positive_duty 158 * 2,3: [FG_CLOCK_ID0, FG_CLK_ID1] 159 * 00: Divide fan clock by 1 160 * 01: Divide fan clock by 2 161 * 10: Divide fan clock by 4 162 * 11: Divide fan clock by 8 163 * 4: FAN_MODE 1:closed-loop, 0:open-loop 164 * 5: OUT_MODE 1:PWM, 0:DC 165 * 6: DET_FAN_OOC enable "fan ooc" status 166 * 7: DET_FAN_FAIL enable "fan fail" status 167 */ 168 u8 fan_cmd2; /* 0,1: FAN_STARTV 0,1,2,3 -> 0,32,64,96 dac_code 169 * 2,3: FG_GEAR_MODE 170 * 00: multiplier = 1 171 * 01: multiplier = 2 172 * 10: multiplier = 4 173 * 4: Mask ALERT# (g763 only) 174 */ 175 }; 176 177 /* 178 * Convert count value from fan controller register (FAN_SET_CNT) into fan 179 * speed RPM value. Note that the datasheet documents a basic formula; 180 * influence of additional parameters (fan clock divisor, fan gear mode) 181 * have been infered from examples in the datasheet and tests. 182 */ 183 static inline unsigned int rpm_from_cnt(u8 cnt, u32 clk_freq, u16 p, 184 u8 clk_div, u8 gear_mult) 185 { 186 if (cnt == 0xff) /* setting cnt to 255 stops the fan */ 187 return 0; 188 189 return (clk_freq * 30 * gear_mult) / ((cnt ? cnt : 1) * p * clk_div); 190 } 191 192 /* 193 * Convert fan RPM value from sysfs into count value for fan controller 194 * register (FAN_SET_CNT). 195 */ 196 static inline unsigned char cnt_from_rpm(unsigned long rpm, u32 clk_freq, u16 p, 197 u8 clk_div, u8 gear_mult) 198 { 199 unsigned long f1 = clk_freq * 30 * gear_mult; 200 unsigned long f2 = p * clk_div; 201 202 if (!rpm) /* to stop the fan, set cnt to 255 */ 203 return 0xff; 204 205 rpm = clamp_val(rpm, f1 / (255 * f2), ULONG_MAX / f2); 206 return DIV_ROUND_CLOSEST(f1, rpm * f2); 207 } 208 209 /* helper to grab and cache data, at most one time per second */ 210 static struct g762_data *g762_update_client(struct device *dev) 211 { 212 struct g762_data *data = dev_get_drvdata(dev); 213 struct i2c_client *client = data->client; 214 int ret = 0; 215 216 mutex_lock(&data->update_lock); 217 if (time_before(jiffies, data->last_updated + G762_UPDATE_INTERVAL) && 218 likely(data->valid)) 219 goto out; 220 221 ret = i2c_smbus_read_byte_data(client, G762_REG_SET_CNT); 222 if (ret < 0) 223 goto out; 224 data->set_cnt = ret; 225 226 ret = i2c_smbus_read_byte_data(client, G762_REG_ACT_CNT); 227 if (ret < 0) 228 goto out; 229 data->act_cnt = ret; 230 231 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_STA); 232 if (ret < 0) 233 goto out; 234 data->fan_sta = ret; 235 236 ret = i2c_smbus_read_byte_data(client, G762_REG_SET_OUT); 237 if (ret < 0) 238 goto out; 239 data->set_out = ret; 240 241 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD1); 242 if (ret < 0) 243 goto out; 244 data->fan_cmd1 = ret; 245 246 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD2); 247 if (ret < 0) 248 goto out; 249 data->fan_cmd2 = ret; 250 251 data->last_updated = jiffies; 252 data->valid = true; 253 out: 254 mutex_unlock(&data->update_lock); 255 256 if (ret < 0) /* upon error, encode it in return value */ 257 data = ERR_PTR(ret); 258 259 return data; 260 } 261 262 /* helpers for writing hardware parameters */ 263 264 /* 265 * Set input clock frequency received on CLK pin of the chip. Accepted values 266 * are between 0 and 0xffffff. If zero is given, then default frequency 267 * (32,768Hz) is used. Note that clock frequency is a characteristic of the 268 * system but an internal parameter, i.e. value is not passed to the device. 269 */ 270 static int do_set_clk_freq(struct device *dev, unsigned long val) 271 { 272 struct g762_data *data = dev_get_drvdata(dev); 273 274 if (val > 0xffffff) 275 return -EINVAL; 276 if (!val) 277 val = 32768; 278 279 data->clk_freq = val; 280 281 return 0; 282 } 283 284 /* Set pwm mode. Accepts either 0 (PWM mode) or 1 (DC mode) */ 285 static int do_set_pwm_mode(struct device *dev, unsigned long val) 286 { 287 struct g762_data *data = g762_update_client(dev); 288 int ret; 289 290 if (IS_ERR(data)) 291 return PTR_ERR(data); 292 293 mutex_lock(&data->update_lock); 294 switch (val) { 295 case G762_OUT_MODE_PWM: 296 data->fan_cmd1 |= G762_REG_FAN_CMD1_OUT_MODE; 297 break; 298 case G762_OUT_MODE_DC: 299 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_OUT_MODE; 300 break; 301 default: 302 ret = -EINVAL; 303 goto out; 304 } 305 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 306 data->fan_cmd1); 307 data->valid = false; 308 out: 309 mutex_unlock(&data->update_lock); 310 311 return ret; 312 } 313 314 /* Set fan clock divisor. Accepts either 1, 2, 4 or 8. */ 315 static int do_set_fan_div(struct device *dev, unsigned long val) 316 { 317 struct g762_data *data = g762_update_client(dev); 318 int ret; 319 320 if (IS_ERR(data)) 321 return PTR_ERR(data); 322 323 mutex_lock(&data->update_lock); 324 switch (val) { 325 case 1: 326 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0; 327 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1; 328 break; 329 case 2: 330 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; 331 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1; 332 break; 333 case 4: 334 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0; 335 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; 336 break; 337 case 8: 338 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; 339 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; 340 break; 341 default: 342 ret = -EINVAL; 343 goto out; 344 } 345 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 346 data->fan_cmd1); 347 data->valid = false; 348 out: 349 mutex_unlock(&data->update_lock); 350 351 return ret; 352 } 353 354 /* Set fan gear mode. Accepts either 0, 1 or 2. */ 355 static int do_set_fan_gear_mode(struct device *dev, unsigned long val) 356 { 357 struct g762_data *data = g762_update_client(dev); 358 int ret; 359 360 if (IS_ERR(data)) 361 return PTR_ERR(data); 362 363 mutex_lock(&data->update_lock); 364 switch (val) { 365 case 0: 366 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; 367 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; 368 break; 369 case 1: 370 data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_0; 371 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; 372 break; 373 case 2: 374 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; 375 data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_1; 376 break; 377 default: 378 ret = -EINVAL; 379 goto out; 380 } 381 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2, 382 data->fan_cmd2); 383 data->valid = false; 384 out: 385 mutex_unlock(&data->update_lock); 386 387 return ret; 388 } 389 390 /* Set number of fan pulses per revolution. Accepts either 2 or 4. */ 391 static int do_set_fan_pulses(struct device *dev, unsigned long val) 392 { 393 struct g762_data *data = g762_update_client(dev); 394 int ret; 395 396 if (IS_ERR(data)) 397 return PTR_ERR(data); 398 399 mutex_lock(&data->update_lock); 400 switch (val) { 401 case 2: 402 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PULSE_PER_REV; 403 break; 404 case 4: 405 data->fan_cmd1 |= G762_REG_FAN_CMD1_PULSE_PER_REV; 406 break; 407 default: 408 ret = -EINVAL; 409 goto out; 410 } 411 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 412 data->fan_cmd1); 413 data->valid = false; 414 out: 415 mutex_unlock(&data->update_lock); 416 417 return ret; 418 } 419 420 /* Set fan mode. Accepts either 1 (open-loop) or 2 (closed-loop). */ 421 static int do_set_pwm_enable(struct device *dev, unsigned long val) 422 { 423 struct g762_data *data = g762_update_client(dev); 424 int ret; 425 426 if (IS_ERR(data)) 427 return PTR_ERR(data); 428 429 mutex_lock(&data->update_lock); 430 switch (val) { 431 case G762_FAN_MODE_CLOSED_LOOP: 432 data->fan_cmd1 |= G762_REG_FAN_CMD1_FAN_MODE; 433 break; 434 case G762_FAN_MODE_OPEN_LOOP: 435 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_FAN_MODE; 436 /* 437 * BUG FIX: if SET_CNT register value is 255 then, for some 438 * unknown reason, fan will not rotate as expected, no matter 439 * the value of SET_OUT (to be specific, this seems to happen 440 * only in PWM mode). To workaround this bug, we give SET_CNT 441 * value of 254 if it is 255 when switching to open-loop. 442 */ 443 if (data->set_cnt == 0xff) 444 i2c_smbus_write_byte_data(data->client, 445 G762_REG_SET_CNT, 254); 446 break; 447 default: 448 ret = -EINVAL; 449 goto out; 450 } 451 452 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 453 data->fan_cmd1); 454 data->valid = false; 455 out: 456 mutex_unlock(&data->update_lock); 457 458 return ret; 459 } 460 461 /* Set PWM polarity. Accepts either 0 (positive duty) or 1 (negative duty) */ 462 static int do_set_pwm_polarity(struct device *dev, unsigned long val) 463 { 464 struct g762_data *data = g762_update_client(dev); 465 int ret; 466 467 if (IS_ERR(data)) 468 return PTR_ERR(data); 469 470 mutex_lock(&data->update_lock); 471 switch (val) { 472 case G762_PWM_POLARITY_POSITIVE: 473 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PWM_POLARITY; 474 break; 475 case G762_PWM_POLARITY_NEGATIVE: 476 data->fan_cmd1 |= G762_REG_FAN_CMD1_PWM_POLARITY; 477 break; 478 default: 479 ret = -EINVAL; 480 goto out; 481 } 482 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 483 data->fan_cmd1); 484 data->valid = false; 485 out: 486 mutex_unlock(&data->update_lock); 487 488 return ret; 489 } 490 491 /* 492 * Set pwm value. Accepts values between 0 (stops the fan) and 493 * 255 (full speed). This only makes sense in open-loop mode. 494 */ 495 static int do_set_pwm(struct device *dev, unsigned long val) 496 { 497 struct g762_data *data = dev_get_drvdata(dev); 498 struct i2c_client *client = data->client; 499 int ret; 500 501 if (val > 255) 502 return -EINVAL; 503 504 mutex_lock(&data->update_lock); 505 ret = i2c_smbus_write_byte_data(client, G762_REG_SET_OUT, val); 506 data->valid = false; 507 mutex_unlock(&data->update_lock); 508 509 return ret; 510 } 511 512 /* 513 * Set fan RPM value. Can be called both in closed and open-loop mode 514 * but effect will only be seen after closed-loop mode is configured. 515 */ 516 static int do_set_fan_target(struct device *dev, unsigned long val) 517 { 518 struct g762_data *data = g762_update_client(dev); 519 int ret; 520 521 if (IS_ERR(data)) 522 return PTR_ERR(data); 523 524 mutex_lock(&data->update_lock); 525 data->set_cnt = cnt_from_rpm(val, data->clk_freq, 526 G762_PULSE_FROM_REG(data->fan_cmd1), 527 G762_CLKDIV_FROM_REG(data->fan_cmd1), 528 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 529 ret = i2c_smbus_write_byte_data(data->client, G762_REG_SET_CNT, 530 data->set_cnt); 531 data->valid = false; 532 mutex_unlock(&data->update_lock); 533 534 return ret; 535 } 536 537 /* Set fan startup voltage. Accepted values are either 0, 1, 2 or 3. */ 538 static int do_set_fan_startv(struct device *dev, unsigned long val) 539 { 540 struct g762_data *data = g762_update_client(dev); 541 int ret; 542 543 if (IS_ERR(data)) 544 return PTR_ERR(data); 545 546 mutex_lock(&data->update_lock); 547 switch (val) { 548 case 0: 549 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0; 550 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1; 551 break; 552 case 1: 553 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; 554 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1; 555 break; 556 case 2: 557 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0; 558 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; 559 break; 560 case 3: 561 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; 562 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; 563 break; 564 default: 565 ret = -EINVAL; 566 goto out; 567 } 568 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2, 569 data->fan_cmd2); 570 data->valid = false; 571 out: 572 mutex_unlock(&data->update_lock); 573 574 return ret; 575 } 576 577 /* 578 * Helper to import hardware characteristics from .dts file and push 579 * those to the chip. 580 */ 581 582 #ifdef CONFIG_OF 583 static const struct of_device_id g762_dt_match[] = { 584 { .compatible = "gmt,g762" }, 585 { .compatible = "gmt,g763" }, 586 { }, 587 }; 588 MODULE_DEVICE_TABLE(of, g762_dt_match); 589 590 /* 591 * Grab clock (a required property), enable it, get (fixed) clock frequency 592 * and store it. Note: upon success, clock has been prepared and enabled; it 593 * must later be unprepared and disabled (e.g. during module unloading) by a 594 * call to g762_of_clock_disable(). Note that a reference to clock is kept 595 * in our private data structure to be used in this function. 596 */ 597 static int g762_of_clock_enable(struct i2c_client *client) 598 { 599 struct g762_data *data; 600 unsigned long clk_freq; 601 struct clk *clk; 602 int ret; 603 604 if (!client->dev.of_node) 605 return 0; 606 607 clk = of_clk_get(client->dev.of_node, 0); 608 if (IS_ERR(clk)) { 609 dev_err(&client->dev, "failed to get clock\n"); 610 return PTR_ERR(clk); 611 } 612 613 ret = clk_prepare_enable(clk); 614 if (ret) { 615 dev_err(&client->dev, "failed to enable clock\n"); 616 goto clk_put; 617 } 618 619 clk_freq = clk_get_rate(clk); 620 ret = do_set_clk_freq(&client->dev, clk_freq); 621 if (ret) { 622 dev_err(&client->dev, "invalid clock freq %lu\n", clk_freq); 623 goto clk_unprep; 624 } 625 626 data = i2c_get_clientdata(client); 627 data->clk = clk; 628 629 return 0; 630 631 clk_unprep: 632 clk_disable_unprepare(clk); 633 634 clk_put: 635 clk_put(clk); 636 637 return ret; 638 } 639 640 static void g762_of_clock_disable(struct i2c_client *client) 641 { 642 struct g762_data *data = i2c_get_clientdata(client); 643 644 if (!data->clk) 645 return; 646 647 clk_disable_unprepare(data->clk); 648 clk_put(data->clk); 649 } 650 651 static int g762_of_prop_import_one(struct i2c_client *client, 652 const char *pname, 653 int (*psetter)(struct device *dev, 654 unsigned long val)) 655 { 656 int ret; 657 u32 pval; 658 659 if (of_property_read_u32(client->dev.of_node, pname, &pval)) 660 return 0; 661 662 dev_dbg(&client->dev, "found %s (%d)\n", pname, pval); 663 ret = (*psetter)(&client->dev, pval); 664 if (ret) 665 dev_err(&client->dev, "unable to set %s (%d)\n", pname, pval); 666 667 return ret; 668 } 669 670 static int g762_of_prop_import(struct i2c_client *client) 671 { 672 int ret; 673 674 if (!client->dev.of_node) 675 return 0; 676 677 ret = g762_of_prop_import_one(client, "fan_gear_mode", 678 do_set_fan_gear_mode); 679 if (ret) 680 return ret; 681 682 ret = g762_of_prop_import_one(client, "pwm_polarity", 683 do_set_pwm_polarity); 684 if (ret) 685 return ret; 686 687 return g762_of_prop_import_one(client, "fan_startv", 688 do_set_fan_startv); 689 } 690 691 #else 692 static int g762_of_prop_import(struct i2c_client *client) 693 { 694 return 0; 695 } 696 697 static int g762_of_clock_enable(struct i2c_client *client) 698 { 699 return 0; 700 } 701 702 static void g762_of_clock_disable(struct i2c_client *client) { } 703 #endif 704 705 /* 706 * Helper to import hardware characteristics from .dts file and push 707 * those to the chip. 708 */ 709 710 static int g762_pdata_prop_import(struct i2c_client *client) 711 { 712 struct g762_platform_data *pdata = dev_get_platdata(&client->dev); 713 int ret; 714 715 if (!pdata) 716 return 0; 717 718 ret = do_set_fan_gear_mode(&client->dev, pdata->fan_gear_mode); 719 if (ret) 720 return ret; 721 722 ret = do_set_pwm_polarity(&client->dev, pdata->pwm_polarity); 723 if (ret) 724 return ret; 725 726 ret = do_set_fan_startv(&client->dev, pdata->fan_startv); 727 if (ret) 728 return ret; 729 730 return do_set_clk_freq(&client->dev, pdata->clk_freq); 731 } 732 733 /* 734 * sysfs attributes 735 */ 736 737 /* 738 * Read function for fan1_input sysfs file. Return current fan RPM value, or 739 * 0 if fan is out of control. 740 */ 741 static ssize_t fan1_input_show(struct device *dev, 742 struct device_attribute *da, char *buf) 743 { 744 struct g762_data *data = g762_update_client(dev); 745 unsigned int rpm = 0; 746 747 if (IS_ERR(data)) 748 return PTR_ERR(data); 749 750 mutex_lock(&data->update_lock); 751 /* reverse logic: fan out of control reporting is enabled low */ 752 if (data->fan_sta & G762_REG_FAN_STA_OOC) { 753 rpm = rpm_from_cnt(data->act_cnt, data->clk_freq, 754 G762_PULSE_FROM_REG(data->fan_cmd1), 755 G762_CLKDIV_FROM_REG(data->fan_cmd1), 756 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 757 } 758 mutex_unlock(&data->update_lock); 759 760 return sprintf(buf, "%u\n", rpm); 761 } 762 763 /* 764 * Read and write functions for pwm1_mode sysfs file. Get and set fan speed 765 * control mode i.e. PWM (1) or DC (0). 766 */ 767 static ssize_t pwm1_mode_show(struct device *dev, struct device_attribute *da, 768 char *buf) 769 { 770 struct g762_data *data = g762_update_client(dev); 771 772 if (IS_ERR(data)) 773 return PTR_ERR(data); 774 775 return sprintf(buf, "%d\n", 776 !!(data->fan_cmd1 & G762_REG_FAN_CMD1_OUT_MODE)); 777 } 778 779 static ssize_t pwm1_mode_store(struct device *dev, 780 struct device_attribute *da, const char *buf, 781 size_t count) 782 { 783 unsigned long val; 784 int ret; 785 786 if (kstrtoul(buf, 10, &val)) 787 return -EINVAL; 788 789 ret = do_set_pwm_mode(dev, val); 790 if (ret < 0) 791 return ret; 792 793 return count; 794 } 795 796 /* 797 * Read and write functions for fan1_div sysfs file. Get and set fan 798 * controller prescaler value 799 */ 800 static ssize_t fan1_div_show(struct device *dev, struct device_attribute *da, 801 char *buf) 802 { 803 struct g762_data *data = g762_update_client(dev); 804 805 if (IS_ERR(data)) 806 return PTR_ERR(data); 807 808 return sprintf(buf, "%d\n", G762_CLKDIV_FROM_REG(data->fan_cmd1)); 809 } 810 811 static ssize_t fan1_div_store(struct device *dev, struct device_attribute *da, 812 const char *buf, size_t count) 813 { 814 unsigned long val; 815 int ret; 816 817 if (kstrtoul(buf, 10, &val)) 818 return -EINVAL; 819 820 ret = do_set_fan_div(dev, val); 821 if (ret < 0) 822 return ret; 823 824 return count; 825 } 826 827 /* 828 * Read and write functions for fan1_pulses sysfs file. Get and set number 829 * of tachometer pulses per fan revolution. 830 */ 831 static ssize_t fan1_pulses_show(struct device *dev, 832 struct device_attribute *da, char *buf) 833 { 834 struct g762_data *data = g762_update_client(dev); 835 836 if (IS_ERR(data)) 837 return PTR_ERR(data); 838 839 return sprintf(buf, "%d\n", G762_PULSE_FROM_REG(data->fan_cmd1)); 840 } 841 842 static ssize_t fan1_pulses_store(struct device *dev, 843 struct device_attribute *da, const char *buf, 844 size_t count) 845 { 846 unsigned long val; 847 int ret; 848 849 if (kstrtoul(buf, 10, &val)) 850 return -EINVAL; 851 852 ret = do_set_fan_pulses(dev, val); 853 if (ret < 0) 854 return ret; 855 856 return count; 857 } 858 859 /* 860 * Read and write functions for pwm1_enable. Get and set fan speed control mode 861 * (i.e. closed or open-loop). 862 * 863 * Following documentation about hwmon's sysfs interface, a pwm1_enable node 864 * should accept the following: 865 * 866 * 0 : no fan speed control (i.e. fan at full speed) 867 * 1 : manual fan speed control enabled (use pwm[1-*]) (open-loop) 868 * 2+: automatic fan speed control enabled (use fan[1-*]_target) (closed-loop) 869 * 870 * but we do not accept 0 as this mode is not natively supported by the chip 871 * and it is not emulated by g762 driver. -EINVAL is returned in this case. 872 */ 873 static ssize_t pwm1_enable_show(struct device *dev, 874 struct device_attribute *da, char *buf) 875 { 876 struct g762_data *data = g762_update_client(dev); 877 878 if (IS_ERR(data)) 879 return PTR_ERR(data); 880 881 return sprintf(buf, "%d\n", 882 (!!(data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE)) + 1); 883 } 884 885 static ssize_t pwm1_enable_store(struct device *dev, 886 struct device_attribute *da, const char *buf, 887 size_t count) 888 { 889 unsigned long val; 890 int ret; 891 892 if (kstrtoul(buf, 10, &val)) 893 return -EINVAL; 894 895 ret = do_set_pwm_enable(dev, val); 896 if (ret < 0) 897 return ret; 898 899 return count; 900 } 901 902 /* 903 * Read and write functions for pwm1 sysfs file. Get and set pwm value 904 * (which affects fan speed) in open-loop mode. 0 stops the fan and 255 905 * makes it run at full speed. 906 */ 907 static ssize_t pwm1_show(struct device *dev, struct device_attribute *da, 908 char *buf) 909 { 910 struct g762_data *data = g762_update_client(dev); 911 912 if (IS_ERR(data)) 913 return PTR_ERR(data); 914 915 return sprintf(buf, "%d\n", data->set_out); 916 } 917 918 static ssize_t pwm1_store(struct device *dev, struct device_attribute *da, 919 const char *buf, size_t count) 920 { 921 unsigned long val; 922 int ret; 923 924 if (kstrtoul(buf, 10, &val)) 925 return -EINVAL; 926 927 ret = do_set_pwm(dev, val); 928 if (ret < 0) 929 return ret; 930 931 return count; 932 } 933 934 /* 935 * Read and write function for fan1_target sysfs file. Get/set the fan speed in 936 * closed-loop mode. Speed is given as a RPM value; then the chip will regulate 937 * the fan speed using pulses from fan tachometer. 938 * 939 * Refer to rpm_from_cnt() implementation above to get info about count number 940 * calculation. 941 * 942 * Also note that due to rounding errors it is possible that you don't read 943 * back exactly the value you have set. 944 */ 945 static ssize_t fan1_target_show(struct device *dev, 946 struct device_attribute *da, char *buf) 947 { 948 struct g762_data *data = g762_update_client(dev); 949 unsigned int rpm; 950 951 if (IS_ERR(data)) 952 return PTR_ERR(data); 953 954 mutex_lock(&data->update_lock); 955 rpm = rpm_from_cnt(data->set_cnt, data->clk_freq, 956 G762_PULSE_FROM_REG(data->fan_cmd1), 957 G762_CLKDIV_FROM_REG(data->fan_cmd1), 958 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 959 mutex_unlock(&data->update_lock); 960 961 return sprintf(buf, "%u\n", rpm); 962 } 963 964 static ssize_t fan1_target_store(struct device *dev, 965 struct device_attribute *da, const char *buf, 966 size_t count) 967 { 968 unsigned long val; 969 int ret; 970 971 if (kstrtoul(buf, 10, &val)) 972 return -EINVAL; 973 974 ret = do_set_fan_target(dev, val); 975 if (ret < 0) 976 return ret; 977 978 return count; 979 } 980 981 /* read function for fan1_fault sysfs file. */ 982 static ssize_t fan1_fault_show(struct device *dev, struct device_attribute *da, 983 char *buf) 984 { 985 struct g762_data *data = g762_update_client(dev); 986 987 if (IS_ERR(data)) 988 return PTR_ERR(data); 989 990 return sprintf(buf, "%u\n", !!(data->fan_sta & G762_REG_FAN_STA_FAIL)); 991 } 992 993 /* 994 * read function for fan1_alarm sysfs file. Note that OOC condition is 995 * enabled low 996 */ 997 static ssize_t fan1_alarm_show(struct device *dev, 998 struct device_attribute *da, char *buf) 999 { 1000 struct g762_data *data = g762_update_client(dev); 1001 1002 if (IS_ERR(data)) 1003 return PTR_ERR(data); 1004 1005 return sprintf(buf, "%u\n", !(data->fan_sta & G762_REG_FAN_STA_OOC)); 1006 } 1007 1008 static DEVICE_ATTR_RW(pwm1); 1009 static DEVICE_ATTR_RW(pwm1_mode); 1010 static DEVICE_ATTR_RW(pwm1_enable); 1011 static DEVICE_ATTR_RO(fan1_input); 1012 static DEVICE_ATTR_RO(fan1_alarm); 1013 static DEVICE_ATTR_RO(fan1_fault); 1014 static DEVICE_ATTR_RW(fan1_target); 1015 static DEVICE_ATTR_RW(fan1_div); 1016 static DEVICE_ATTR_RW(fan1_pulses); 1017 1018 /* Driver data */ 1019 static struct attribute *g762_attrs[] = { 1020 &dev_attr_fan1_input.attr, 1021 &dev_attr_fan1_alarm.attr, 1022 &dev_attr_fan1_fault.attr, 1023 &dev_attr_fan1_target.attr, 1024 &dev_attr_fan1_div.attr, 1025 &dev_attr_fan1_pulses.attr, 1026 &dev_attr_pwm1.attr, 1027 &dev_attr_pwm1_mode.attr, 1028 &dev_attr_pwm1_enable.attr, 1029 NULL 1030 }; 1031 1032 ATTRIBUTE_GROUPS(g762); 1033 1034 /* 1035 * Enable both fan failure detection and fan out of control protection. The 1036 * function does not protect change/access to data structure; it must thus 1037 * only be called during initialization. 1038 */ 1039 static inline int g762_fan_init(struct device *dev) 1040 { 1041 struct g762_data *data = g762_update_client(dev); 1042 1043 if (IS_ERR(data)) 1044 return PTR_ERR(data); 1045 1046 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL; 1047 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC; 1048 data->valid = false; 1049 1050 return i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 1051 data->fan_cmd1); 1052 } 1053 1054 static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id) 1055 { 1056 struct device *dev = &client->dev; 1057 struct g762_data *data; 1058 int ret; 1059 1060 if (!i2c_check_functionality(client->adapter, 1061 I2C_FUNC_SMBUS_BYTE_DATA)) 1062 return -ENODEV; 1063 1064 data = devm_kzalloc(dev, sizeof(struct g762_data), GFP_KERNEL); 1065 if (!data) 1066 return -ENOMEM; 1067 1068 i2c_set_clientdata(client, data); 1069 data->client = client; 1070 mutex_init(&data->update_lock); 1071 1072 /* Enable fan failure detection and fan out of control protection */ 1073 ret = g762_fan_init(dev); 1074 if (ret) 1075 return ret; 1076 1077 /* Get configuration via DT ... */ 1078 ret = g762_of_clock_enable(client); 1079 if (ret) 1080 return ret; 1081 ret = g762_of_prop_import(client); 1082 if (ret) 1083 goto clock_dis; 1084 /* ... or platform_data */ 1085 ret = g762_pdata_prop_import(client); 1086 if (ret) 1087 goto clock_dis; 1088 1089 data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name, 1090 data, g762_groups); 1091 if (IS_ERR(data->hwmon_dev)) { 1092 ret = PTR_ERR(data->hwmon_dev); 1093 goto clock_dis; 1094 } 1095 1096 return 0; 1097 1098 clock_dis: 1099 g762_of_clock_disable(client); 1100 1101 return ret; 1102 } 1103 1104 static int g762_remove(struct i2c_client *client) 1105 { 1106 struct g762_data *data = i2c_get_clientdata(client); 1107 1108 hwmon_device_unregister(data->hwmon_dev); 1109 g762_of_clock_disable(client); 1110 1111 return 0; 1112 } 1113 1114 static struct i2c_driver g762_driver = { 1115 .driver = { 1116 .name = DRVNAME, 1117 .of_match_table = of_match_ptr(g762_dt_match), 1118 }, 1119 .probe = g762_probe, 1120 .remove = g762_remove, 1121 .id_table = g762_id, 1122 }; 1123 1124 module_i2c_driver(g762_driver); 1125 1126 MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>"); 1127 MODULE_DESCRIPTION("GMT G762/G763 driver"); 1128 MODULE_LICENSE("GPL"); 1129