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(u32 rpm, u32 clk_freq, u16 p, 197 u8 clk_div, u8 gear_mult) 198 { 199 if (!rpm) /* to stop the fan, set cnt to 255 */ 200 return 0xff; 201 202 return clamp_val(((clk_freq * 30 * gear_mult) / (rpm * p * clk_div)), 203 0, 255); 204 } 205 206 /* helper to grab and cache data, at most one time per second */ 207 static struct g762_data *g762_update_client(struct device *dev) 208 { 209 struct g762_data *data = dev_get_drvdata(dev); 210 struct i2c_client *client = data->client; 211 int ret = 0; 212 213 mutex_lock(&data->update_lock); 214 if (time_before(jiffies, data->last_updated + G762_UPDATE_INTERVAL) && 215 likely(data->valid)) 216 goto out; 217 218 ret = i2c_smbus_read_byte_data(client, G762_REG_SET_CNT); 219 if (ret < 0) 220 goto out; 221 data->set_cnt = ret; 222 223 ret = i2c_smbus_read_byte_data(client, G762_REG_ACT_CNT); 224 if (ret < 0) 225 goto out; 226 data->act_cnt = ret; 227 228 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_STA); 229 if (ret < 0) 230 goto out; 231 data->fan_sta = ret; 232 233 ret = i2c_smbus_read_byte_data(client, G762_REG_SET_OUT); 234 if (ret < 0) 235 goto out; 236 data->set_out = ret; 237 238 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD1); 239 if (ret < 0) 240 goto out; 241 data->fan_cmd1 = ret; 242 243 ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD2); 244 if (ret < 0) 245 goto out; 246 data->fan_cmd2 = ret; 247 248 data->last_updated = jiffies; 249 data->valid = true; 250 out: 251 mutex_unlock(&data->update_lock); 252 253 if (ret < 0) /* upon error, encode it in return value */ 254 data = ERR_PTR(ret); 255 256 return data; 257 } 258 259 /* helpers for writing hardware parameters */ 260 261 /* 262 * Set input clock frequency received on CLK pin of the chip. Accepted values 263 * are between 0 and 0xffffff. If zero is given, then default frequency 264 * (32,768Hz) is used. Note that clock frequency is a characteristic of the 265 * system but an internal parameter, i.e. value is not passed to the device. 266 */ 267 static int do_set_clk_freq(struct device *dev, unsigned long val) 268 { 269 struct g762_data *data = dev_get_drvdata(dev); 270 271 if (val > 0xffffff) 272 return -EINVAL; 273 if (!val) 274 val = 32768; 275 276 data->clk_freq = val; 277 278 return 0; 279 } 280 281 /* Set pwm mode. Accepts either 0 (PWM mode) or 1 (DC mode) */ 282 static int do_set_pwm_mode(struct device *dev, unsigned long val) 283 { 284 struct g762_data *data = g762_update_client(dev); 285 int ret; 286 287 if (IS_ERR(data)) 288 return PTR_ERR(data); 289 290 mutex_lock(&data->update_lock); 291 switch (val) { 292 case G762_OUT_MODE_PWM: 293 data->fan_cmd1 |= G762_REG_FAN_CMD1_OUT_MODE; 294 break; 295 case G762_OUT_MODE_DC: 296 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_OUT_MODE; 297 break; 298 default: 299 ret = -EINVAL; 300 goto out; 301 } 302 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 303 data->fan_cmd1); 304 data->valid = false; 305 out: 306 mutex_unlock(&data->update_lock); 307 308 return ret; 309 } 310 311 /* Set fan clock divisor. Accepts either 1, 2, 4 or 8. */ 312 static int do_set_fan_div(struct device *dev, unsigned long val) 313 { 314 struct g762_data *data = g762_update_client(dev); 315 int ret; 316 317 if (IS_ERR(data)) 318 return PTR_ERR(data); 319 320 mutex_lock(&data->update_lock); 321 switch (val) { 322 case 1: 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 case 2: 327 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; 328 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1; 329 break; 330 case 4: 331 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0; 332 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; 333 break; 334 case 8: 335 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; 336 data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; 337 break; 338 default: 339 ret = -EINVAL; 340 goto out; 341 } 342 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 343 data->fan_cmd1); 344 data->valid = false; 345 out: 346 mutex_unlock(&data->update_lock); 347 348 return ret; 349 } 350 351 /* Set fan gear mode. Accepts either 0, 1 or 2. */ 352 static int do_set_fan_gear_mode(struct device *dev, unsigned long val) 353 { 354 struct g762_data *data = g762_update_client(dev); 355 int ret; 356 357 if (IS_ERR(data)) 358 return PTR_ERR(data); 359 360 mutex_lock(&data->update_lock); 361 switch (val) { 362 case 0: 363 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; 364 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; 365 break; 366 case 1: 367 data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_0; 368 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; 369 break; 370 case 2: 371 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; 372 data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_1; 373 break; 374 default: 375 ret = -EINVAL; 376 goto out; 377 } 378 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2, 379 data->fan_cmd2); 380 data->valid = false; 381 out: 382 mutex_unlock(&data->update_lock); 383 384 return ret; 385 } 386 387 /* Set number of fan pulses per revolution. Accepts either 2 or 4. */ 388 static int do_set_fan_pulses(struct device *dev, unsigned long val) 389 { 390 struct g762_data *data = g762_update_client(dev); 391 int ret; 392 393 if (IS_ERR(data)) 394 return PTR_ERR(data); 395 396 mutex_lock(&data->update_lock); 397 switch (val) { 398 case 2: 399 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PULSE_PER_REV; 400 break; 401 case 4: 402 data->fan_cmd1 |= G762_REG_FAN_CMD1_PULSE_PER_REV; 403 break; 404 default: 405 ret = -EINVAL; 406 goto out; 407 } 408 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 409 data->fan_cmd1); 410 data->valid = false; 411 out: 412 mutex_unlock(&data->update_lock); 413 414 return ret; 415 } 416 417 /* Set fan mode. Accepts either 1 (open-loop) or 2 (closed-loop). */ 418 static int do_set_pwm_enable(struct device *dev, unsigned long val) 419 { 420 struct g762_data *data = g762_update_client(dev); 421 int ret; 422 423 if (IS_ERR(data)) 424 return PTR_ERR(data); 425 426 mutex_lock(&data->update_lock); 427 switch (val) { 428 case G762_FAN_MODE_CLOSED_LOOP: 429 data->fan_cmd1 |= G762_REG_FAN_CMD1_FAN_MODE; 430 break; 431 case G762_FAN_MODE_OPEN_LOOP: 432 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_FAN_MODE; 433 /* 434 * BUG FIX: if SET_CNT register value is 255 then, for some 435 * unknown reason, fan will not rotate as expected, no matter 436 * the value of SET_OUT (to be specific, this seems to happen 437 * only in PWM mode). To workaround this bug, we give SET_CNT 438 * value of 254 if it is 255 when switching to open-loop. 439 */ 440 if (data->set_cnt == 0xff) 441 i2c_smbus_write_byte_data(data->client, 442 G762_REG_SET_CNT, 254); 443 break; 444 default: 445 ret = -EINVAL; 446 goto out; 447 } 448 449 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 450 data->fan_cmd1); 451 data->valid = false; 452 out: 453 mutex_unlock(&data->update_lock); 454 455 return ret; 456 } 457 458 /* Set PWM polarity. Accepts either 0 (positive duty) or 1 (negative duty) */ 459 static int do_set_pwm_polarity(struct device *dev, unsigned long val) 460 { 461 struct g762_data *data = g762_update_client(dev); 462 int ret; 463 464 if (IS_ERR(data)) 465 return PTR_ERR(data); 466 467 mutex_lock(&data->update_lock); 468 switch (val) { 469 case G762_PWM_POLARITY_POSITIVE: 470 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PWM_POLARITY; 471 break; 472 case G762_PWM_POLARITY_NEGATIVE: 473 data->fan_cmd1 |= G762_REG_FAN_CMD1_PWM_POLARITY; 474 break; 475 default: 476 ret = -EINVAL; 477 goto out; 478 } 479 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 480 data->fan_cmd1); 481 data->valid = false; 482 out: 483 mutex_unlock(&data->update_lock); 484 485 return ret; 486 } 487 488 /* 489 * Set pwm value. Accepts values between 0 (stops the fan) and 490 * 255 (full speed). This only makes sense in open-loop mode. 491 */ 492 static int do_set_pwm(struct device *dev, unsigned long val) 493 { 494 struct g762_data *data = dev_get_drvdata(dev); 495 struct i2c_client *client = data->client; 496 int ret; 497 498 if (val > 255) 499 return -EINVAL; 500 501 mutex_lock(&data->update_lock); 502 ret = i2c_smbus_write_byte_data(client, G762_REG_SET_OUT, val); 503 data->valid = false; 504 mutex_unlock(&data->update_lock); 505 506 return ret; 507 } 508 509 /* 510 * Set fan RPM value. Can be called both in closed and open-loop mode 511 * but effect will only be seen after closed-loop mode is configured. 512 */ 513 static int do_set_fan_target(struct device *dev, unsigned long val) 514 { 515 struct g762_data *data = g762_update_client(dev); 516 int ret; 517 518 if (IS_ERR(data)) 519 return PTR_ERR(data); 520 521 mutex_lock(&data->update_lock); 522 data->set_cnt = cnt_from_rpm(val, data->clk_freq, 523 G762_PULSE_FROM_REG(data->fan_cmd1), 524 G762_CLKDIV_FROM_REG(data->fan_cmd1), 525 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 526 ret = i2c_smbus_write_byte_data(data->client, G762_REG_SET_CNT, 527 data->set_cnt); 528 data->valid = false; 529 mutex_unlock(&data->update_lock); 530 531 return ret; 532 } 533 534 /* Set fan startup voltage. Accepted values are either 0, 1, 2 or 3. */ 535 static int do_set_fan_startv(struct device *dev, unsigned long val) 536 { 537 struct g762_data *data = g762_update_client(dev); 538 int ret; 539 540 if (IS_ERR(data)) 541 return PTR_ERR(data); 542 543 mutex_lock(&data->update_lock); 544 switch (val) { 545 case 0: 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 case 1: 550 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; 551 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1; 552 break; 553 case 2: 554 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0; 555 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; 556 break; 557 case 3: 558 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; 559 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; 560 break; 561 default: 562 ret = -EINVAL; 563 goto out; 564 } 565 ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2, 566 data->fan_cmd2); 567 data->valid = false; 568 out: 569 mutex_unlock(&data->update_lock); 570 571 return ret; 572 } 573 574 /* 575 * Helper to import hardware characteristics from .dts file and push 576 * those to the chip. 577 */ 578 579 #ifdef CONFIG_OF 580 static const struct of_device_id g762_dt_match[] = { 581 { .compatible = "gmt,g762" }, 582 { .compatible = "gmt,g763" }, 583 { }, 584 }; 585 586 /* 587 * Grab clock (a required property), enable it, get (fixed) clock frequency 588 * and store it. Note: upon success, clock has been prepared and enabled; it 589 * must later be unprepared and disabled (e.g. during module unloading) by a 590 * call to g762_of_clock_disable(). Note that a reference to clock is kept 591 * in our private data structure to be used in this function. 592 */ 593 static int g762_of_clock_enable(struct i2c_client *client) 594 { 595 struct g762_data *data; 596 unsigned long clk_freq; 597 struct clk *clk; 598 int ret; 599 600 if (!client->dev.of_node) 601 return 0; 602 603 clk = of_clk_get(client->dev.of_node, 0); 604 if (IS_ERR(clk)) { 605 dev_err(&client->dev, "failed to get clock\n"); 606 return PTR_ERR(clk); 607 } 608 609 ret = clk_prepare_enable(clk); 610 if (ret) { 611 dev_err(&client->dev, "failed to enable clock\n"); 612 goto clk_put; 613 } 614 615 clk_freq = clk_get_rate(clk); 616 ret = do_set_clk_freq(&client->dev, clk_freq); 617 if (ret) { 618 dev_err(&client->dev, "invalid clock freq %lu\n", clk_freq); 619 goto clk_unprep; 620 } 621 622 data = i2c_get_clientdata(client); 623 data->clk = clk; 624 625 return 0; 626 627 clk_unprep: 628 clk_disable_unprepare(clk); 629 630 clk_put: 631 clk_put(clk); 632 633 return ret; 634 } 635 636 static void g762_of_clock_disable(struct i2c_client *client) 637 { 638 struct g762_data *data = i2c_get_clientdata(client); 639 640 if (!data->clk) 641 return; 642 643 clk_disable_unprepare(data->clk); 644 clk_put(data->clk); 645 } 646 647 static int g762_of_prop_import_one(struct i2c_client *client, 648 const char *pname, 649 int (*psetter)(struct device *dev, 650 unsigned long val)) 651 { 652 int ret; 653 u32 pval; 654 655 if (of_property_read_u32(client->dev.of_node, pname, &pval)) 656 return 0; 657 658 dev_dbg(&client->dev, "found %s (%d)\n", pname, pval); 659 ret = (*psetter)(&client->dev, pval); 660 if (ret) 661 dev_err(&client->dev, "unable to set %s (%d)\n", pname, pval); 662 663 return ret; 664 } 665 666 static int g762_of_prop_import(struct i2c_client *client) 667 { 668 int ret; 669 670 if (!client->dev.of_node) 671 return 0; 672 673 ret = g762_of_prop_import_one(client, "fan_gear_mode", 674 do_set_fan_gear_mode); 675 if (ret) 676 return ret; 677 678 ret = g762_of_prop_import_one(client, "pwm_polarity", 679 do_set_pwm_polarity); 680 if (ret) 681 return ret; 682 683 return g762_of_prop_import_one(client, "fan_startv", 684 do_set_fan_startv); 685 } 686 687 #else 688 static int g762_of_prop_import(struct i2c_client *client) 689 { 690 return 0; 691 } 692 693 static int g762_of_clock_enable(struct i2c_client *client) 694 { 695 return 0; 696 } 697 698 static void g762_of_clock_disable(struct i2c_client *client) { } 699 #endif 700 701 /* 702 * Helper to import hardware characteristics from .dts file and push 703 * those to the chip. 704 */ 705 706 static int g762_pdata_prop_import(struct i2c_client *client) 707 { 708 struct g762_platform_data *pdata = dev_get_platdata(&client->dev); 709 int ret; 710 711 if (!pdata) 712 return 0; 713 714 ret = do_set_fan_gear_mode(&client->dev, pdata->fan_gear_mode); 715 if (ret) 716 return ret; 717 718 ret = do_set_pwm_polarity(&client->dev, pdata->pwm_polarity); 719 if (ret) 720 return ret; 721 722 ret = do_set_fan_startv(&client->dev, pdata->fan_startv); 723 if (ret) 724 return ret; 725 726 return do_set_clk_freq(&client->dev, pdata->clk_freq); 727 } 728 729 /* 730 * sysfs attributes 731 */ 732 733 /* 734 * Read function for fan1_input sysfs file. Return current fan RPM value, or 735 * 0 if fan is out of control. 736 */ 737 static ssize_t get_fan_rpm(struct device *dev, struct device_attribute *da, 738 char *buf) 739 { 740 struct g762_data *data = g762_update_client(dev); 741 unsigned int rpm = 0; 742 743 if (IS_ERR(data)) 744 return PTR_ERR(data); 745 746 mutex_lock(&data->update_lock); 747 /* reverse logic: fan out of control reporting is enabled low */ 748 if (data->fan_sta & G762_REG_FAN_STA_OOC) { 749 rpm = rpm_from_cnt(data->act_cnt, data->clk_freq, 750 G762_PULSE_FROM_REG(data->fan_cmd1), 751 G762_CLKDIV_FROM_REG(data->fan_cmd1), 752 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 753 } 754 mutex_unlock(&data->update_lock); 755 756 return sprintf(buf, "%u\n", rpm); 757 } 758 759 /* 760 * Read and write functions for pwm1_mode sysfs file. Get and set fan speed 761 * control mode i.e. PWM (1) or DC (0). 762 */ 763 static ssize_t get_pwm_mode(struct device *dev, struct device_attribute *da, 764 char *buf) 765 { 766 struct g762_data *data = g762_update_client(dev); 767 768 if (IS_ERR(data)) 769 return PTR_ERR(data); 770 771 return sprintf(buf, "%d\n", 772 !!(data->fan_cmd1 & G762_REG_FAN_CMD1_OUT_MODE)); 773 } 774 775 static ssize_t set_pwm_mode(struct device *dev, struct device_attribute *da, 776 const char *buf, size_t count) 777 { 778 unsigned long val; 779 int ret; 780 781 if (kstrtoul(buf, 10, &val)) 782 return -EINVAL; 783 784 ret = do_set_pwm_mode(dev, val); 785 if (ret < 0) 786 return ret; 787 788 return count; 789 } 790 791 /* 792 * Read and write functions for fan1_div sysfs file. Get and set fan 793 * controller prescaler value 794 */ 795 static ssize_t get_fan_div(struct device *dev, 796 struct device_attribute *da, char *buf) 797 { 798 struct g762_data *data = g762_update_client(dev); 799 800 if (IS_ERR(data)) 801 return PTR_ERR(data); 802 803 return sprintf(buf, "%d\n", G762_CLKDIV_FROM_REG(data->fan_cmd1)); 804 } 805 806 static ssize_t set_fan_div(struct device *dev, 807 struct device_attribute *da, 808 const char *buf, size_t count) 809 { 810 unsigned long val; 811 int ret; 812 813 if (kstrtoul(buf, 10, &val)) 814 return -EINVAL; 815 816 ret = do_set_fan_div(dev, val); 817 if (ret < 0) 818 return ret; 819 820 return count; 821 } 822 823 /* 824 * Read and write functions for fan1_pulses sysfs file. Get and set number 825 * of tachometer pulses per fan revolution. 826 */ 827 static ssize_t get_fan_pulses(struct device *dev, 828 struct device_attribute *da, char *buf) 829 { 830 struct g762_data *data = g762_update_client(dev); 831 832 if (IS_ERR(data)) 833 return PTR_ERR(data); 834 835 return sprintf(buf, "%d\n", G762_PULSE_FROM_REG(data->fan_cmd1)); 836 } 837 838 static ssize_t set_fan_pulses(struct device *dev, 839 struct device_attribute *da, 840 const char *buf, size_t count) 841 { 842 unsigned long val; 843 int ret; 844 845 if (kstrtoul(buf, 10, &val)) 846 return -EINVAL; 847 848 ret = do_set_fan_pulses(dev, val); 849 if (ret < 0) 850 return ret; 851 852 return count; 853 } 854 855 /* 856 * Read and write functions for pwm1_enable. Get and set fan speed control mode 857 * (i.e. closed or open-loop). 858 * 859 * Following documentation about hwmon's sysfs interface, a pwm1_enable node 860 * should accept followings: 861 * 862 * 0 : no fan speed control (i.e. fan at full speed) 863 * 1 : manual fan speed control enabled (use pwm[1-*]) (open-loop) 864 * 2+: automatic fan speed control enabled (use fan[1-*]_target) (closed-loop) 865 * 866 * but we do not accept 0 as this mode is not natively supported by the chip 867 * and it is not emulated by g762 driver. -EINVAL is returned in this case. 868 */ 869 static ssize_t get_pwm_enable(struct device *dev, 870 struct device_attribute *da, char *buf) 871 { 872 struct g762_data *data = g762_update_client(dev); 873 874 if (IS_ERR(data)) 875 return PTR_ERR(data); 876 877 return sprintf(buf, "%d\n", 878 (!!(data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE)) + 1); 879 } 880 881 static ssize_t set_pwm_enable(struct device *dev, 882 struct device_attribute *da, 883 const char *buf, size_t count) 884 { 885 unsigned long val; 886 int ret; 887 888 if (kstrtoul(buf, 10, &val)) 889 return -EINVAL; 890 891 ret = do_set_pwm_enable(dev, val); 892 if (ret < 0) 893 return ret; 894 895 return count; 896 } 897 898 /* 899 * Read and write functions for pwm1 sysfs file. Get and set pwm value 900 * (which affects fan speed) in open-loop mode. 0 stops the fan and 255 901 * makes it run at full speed. 902 */ 903 static ssize_t get_pwm(struct device *dev, struct device_attribute *da, 904 char *buf) 905 { 906 struct g762_data *data = g762_update_client(dev); 907 908 if (IS_ERR(data)) 909 return PTR_ERR(data); 910 911 return sprintf(buf, "%d\n", data->set_out); 912 } 913 914 static ssize_t set_pwm(struct device *dev, struct device_attribute *da, 915 const char *buf, size_t count) 916 { 917 unsigned long val; 918 int ret; 919 920 if (kstrtoul(buf, 10, &val)) 921 return -EINVAL; 922 923 ret = do_set_pwm(dev, val); 924 if (ret < 0) 925 return ret; 926 927 return count; 928 } 929 930 /* 931 * Read and write function for fan1_target sysfs file. Get/set the fan speed in 932 * closed-loop mode. Speed is given as a RPM value; then the chip will regulate 933 * the fan speed using pulses from fan tachometer. 934 * 935 * Refer to rpm_from_cnt() implementation above to get info about count number 936 * calculation. 937 * 938 * Also note that due to rounding errors it is possible that you don't read 939 * back exactly the value you have set. 940 */ 941 static ssize_t get_fan_target(struct device *dev, struct device_attribute *da, 942 char *buf) 943 { 944 struct g762_data *data = g762_update_client(dev); 945 unsigned int rpm; 946 947 if (IS_ERR(data)) 948 return PTR_ERR(data); 949 950 mutex_lock(&data->update_lock); 951 rpm = rpm_from_cnt(data->set_cnt, data->clk_freq, 952 G762_PULSE_FROM_REG(data->fan_cmd1), 953 G762_CLKDIV_FROM_REG(data->fan_cmd1), 954 G762_GEARMULT_FROM_REG(data->fan_cmd2)); 955 mutex_unlock(&data->update_lock); 956 957 return sprintf(buf, "%u\n", rpm); 958 } 959 960 static ssize_t set_fan_target(struct device *dev, struct device_attribute *da, 961 const char *buf, size_t count) 962 { 963 unsigned long val; 964 int ret; 965 966 if (kstrtoul(buf, 10, &val)) 967 return -EINVAL; 968 969 ret = do_set_fan_target(dev, val); 970 if (ret < 0) 971 return ret; 972 973 return count; 974 } 975 976 /* read function for fan1_fault sysfs file. */ 977 static ssize_t get_fan_failure(struct device *dev, struct device_attribute *da, 978 char *buf) 979 { 980 struct g762_data *data = g762_update_client(dev); 981 982 if (IS_ERR(data)) 983 return PTR_ERR(data); 984 985 return sprintf(buf, "%u\n", !!(data->fan_sta & G762_REG_FAN_STA_FAIL)); 986 } 987 988 /* 989 * read function for fan1_alarm sysfs file. Note that OOC condition is 990 * enabled low 991 */ 992 static ssize_t get_fan_ooc(struct device *dev, struct device_attribute *da, 993 char *buf) 994 { 995 struct g762_data *data = g762_update_client(dev); 996 997 if (IS_ERR(data)) 998 return PTR_ERR(data); 999 1000 return sprintf(buf, "%u\n", !(data->fan_sta & G762_REG_FAN_STA_OOC)); 1001 } 1002 1003 static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm); 1004 static DEVICE_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, get_pwm_mode, set_pwm_mode); 1005 static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, 1006 get_pwm_enable, set_pwm_enable); 1007 static DEVICE_ATTR(fan1_input, S_IRUGO, get_fan_rpm, NULL); 1008 static DEVICE_ATTR(fan1_alarm, S_IRUGO, get_fan_ooc, NULL); 1009 static DEVICE_ATTR(fan1_fault, S_IRUGO, get_fan_failure, NULL); 1010 static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO, 1011 get_fan_target, set_fan_target); 1012 static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_fan_div, set_fan_div); 1013 static DEVICE_ATTR(fan1_pulses, S_IWUSR | S_IRUGO, 1014 get_fan_pulses, set_fan_pulses); 1015 1016 /* Driver data */ 1017 static struct attribute *g762_attrs[] = { 1018 &dev_attr_fan1_input.attr, 1019 &dev_attr_fan1_alarm.attr, 1020 &dev_attr_fan1_fault.attr, 1021 &dev_attr_fan1_target.attr, 1022 &dev_attr_fan1_div.attr, 1023 &dev_attr_fan1_pulses.attr, 1024 &dev_attr_pwm1.attr, 1025 &dev_attr_pwm1_mode.attr, 1026 &dev_attr_pwm1_enable.attr, 1027 NULL 1028 }; 1029 1030 ATTRIBUTE_GROUPS(g762); 1031 1032 /* 1033 * Enable both fan failure detection and fan out of control protection. The 1034 * function does not protect change/access to data structure; it must thus 1035 * only be called during initialization. 1036 */ 1037 static inline int g762_fan_init(struct device *dev) 1038 { 1039 struct g762_data *data = g762_update_client(dev); 1040 1041 if (IS_ERR(data)) 1042 return PTR_ERR(data); 1043 1044 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL; 1045 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC; 1046 data->valid = false; 1047 1048 return i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1, 1049 data->fan_cmd1); 1050 } 1051 1052 static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id) 1053 { 1054 struct device *dev = &client->dev; 1055 struct g762_data *data; 1056 int ret; 1057 1058 if (!i2c_check_functionality(client->adapter, 1059 I2C_FUNC_SMBUS_BYTE_DATA)) 1060 return -ENODEV; 1061 1062 data = devm_kzalloc(dev, sizeof(struct g762_data), GFP_KERNEL); 1063 if (!data) 1064 return -ENOMEM; 1065 1066 i2c_set_clientdata(client, data); 1067 data->client = client; 1068 mutex_init(&data->update_lock); 1069 1070 /* Enable fan failure detection and fan out of control protection */ 1071 ret = g762_fan_init(dev); 1072 if (ret) 1073 return ret; 1074 1075 /* Get configuration via DT ... */ 1076 ret = g762_of_clock_enable(client); 1077 if (ret) 1078 return ret; 1079 ret = g762_of_prop_import(client); 1080 if (ret) 1081 goto clock_dis; 1082 /* ... or platform_data */ 1083 ret = g762_pdata_prop_import(client); 1084 if (ret) 1085 goto clock_dis; 1086 1087 data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name, 1088 data, g762_groups); 1089 if (IS_ERR(data->hwmon_dev)) { 1090 ret = PTR_ERR(data->hwmon_dev); 1091 goto clock_dis; 1092 } 1093 1094 return 0; 1095 1096 clock_dis: 1097 g762_of_clock_disable(client); 1098 1099 return ret; 1100 } 1101 1102 static int g762_remove(struct i2c_client *client) 1103 { 1104 struct g762_data *data = i2c_get_clientdata(client); 1105 1106 hwmon_device_unregister(data->hwmon_dev); 1107 g762_of_clock_disable(client); 1108 1109 return 0; 1110 } 1111 1112 static struct i2c_driver g762_driver = { 1113 .driver = { 1114 .name = DRVNAME, 1115 .owner = THIS_MODULE, 1116 .of_match_table = of_match_ptr(g762_dt_match), 1117 }, 1118 .probe = g762_probe, 1119 .remove = g762_remove, 1120 .id_table = g762_id, 1121 }; 1122 1123 module_i2c_driver(g762_driver); 1124 1125 MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>"); 1126 MODULE_DESCRIPTION("GMT G762/G763 driver"); 1127 MODULE_LICENSE("GPL"); 1128