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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
60static const struct i2c_device_id g762_id[] = {
61 { "g762", 0 },
62 { "g763", 0 },
63 { }
64};
65MODULE_DEVICE_TABLE(i2c, g762_id);
66
67enum 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
130struct 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 */
183static 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 */
196static 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 */
210static 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 */
270static 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) */
285static 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. */
315static 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. */
355static 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. */
391static 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). */
421static 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) */
462static 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 */
495static 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 */
516static 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. */
538static 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
583static const struct of_device_id g762_dt_match[] = {
584 { .compatible = "gmt,g762" },
585 { .compatible = "gmt,g763" },
586 { },
587};
588MODULE_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 */
597static 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
640static 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
651static 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
670static 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
692static int g762_of_prop_import(struct i2c_client *client)
693{
694 return 0;
695}
696
697static int g762_of_clock_enable(struct i2c_client *client)
698{
699 return 0;
700}
701
702static 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
710static 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 */
741static ssize_t get_fan_rpm(struct device *dev, struct device_attribute *da,
742 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 */
767static ssize_t get_pwm_mode(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
779static ssize_t set_pwm_mode(struct device *dev, struct device_attribute *da,
780 const char *buf, size_t count)
781{
782 unsigned long val;
783 int ret;
784
785 if (kstrtoul(buf, 10, &val))
786 return -EINVAL;
787
788 ret = do_set_pwm_mode(dev, val);
789 if (ret < 0)
790 return ret;
791
792 return count;
793}
794
795/*
796 * Read and write functions for fan1_div sysfs file. Get and set fan
797 * controller prescaler value
798 */
799static ssize_t get_fan_div(struct device *dev,
800 struct device_attribute *da, char *buf)
801{
802 struct g762_data *data = g762_update_client(dev);
803
804 if (IS_ERR(data))
805 return PTR_ERR(data);
806
807 return sprintf(buf, "%d\n", G762_CLKDIV_FROM_REG(data->fan_cmd1));
808}
809
810static ssize_t set_fan_div(struct device *dev,
811 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 */
831static ssize_t get_fan_pulses(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
842static ssize_t set_fan_pulses(struct device *dev,
843 struct device_attribute *da,
844 const char *buf, 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 followings:
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 */
873static ssize_t get_pwm_enable(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
885static ssize_t set_pwm_enable(struct device *dev,
886 struct device_attribute *da,
887 const char *buf, 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 */
907static ssize_t get_pwm(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
918static ssize_t set_pwm(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 */
945static ssize_t get_fan_target(struct device *dev, struct device_attribute *da,
946 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
964static ssize_t set_fan_target(struct device *dev, struct device_attribute *da,
965 const char *buf, size_t count)
966{
967 unsigned long val;
968 int ret;
969
970 if (kstrtoul(buf, 10, &val))
971 return -EINVAL;
972
973 ret = do_set_fan_target(dev, val);
974 if (ret < 0)
975 return ret;
976
977 return count;
978}
979
980/* read function for fan1_fault sysfs file. */
981static ssize_t get_fan_failure(struct device *dev, struct device_attribute *da,
982 char *buf)
983{
984 struct g762_data *data = g762_update_client(dev);
985
986 if (IS_ERR(data))
987 return PTR_ERR(data);
988
989 return sprintf(buf, "%u\n", !!(data->fan_sta & G762_REG_FAN_STA_FAIL));
990}
991
992/*
993 * read function for fan1_alarm sysfs file. Note that OOC condition is
994 * enabled low
995 */
996static ssize_t get_fan_ooc(struct device *dev, struct device_attribute *da,
997 char *buf)
998{
999 struct g762_data *data = g762_update_client(dev);
1000
1001 if (IS_ERR(data))
1002 return PTR_ERR(data);
1003
1004 return sprintf(buf, "%u\n", !(data->fan_sta & G762_REG_FAN_STA_OOC));
1005}
1006
1007static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
1008static DEVICE_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, get_pwm_mode, set_pwm_mode);
1009static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO,
1010 get_pwm_enable, set_pwm_enable);
1011static DEVICE_ATTR(fan1_input, S_IRUGO, get_fan_rpm, NULL);
1012static DEVICE_ATTR(fan1_alarm, S_IRUGO, get_fan_ooc, NULL);
1013static DEVICE_ATTR(fan1_fault, S_IRUGO, get_fan_failure, NULL);
1014static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO,
1015 get_fan_target, set_fan_target);
1016static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_fan_div, set_fan_div);
1017static DEVICE_ATTR(fan1_pulses, S_IWUSR | S_IRUGO,
1018 get_fan_pulses, set_fan_pulses);
1019
1020/* Driver data */
1021static struct attribute *g762_attrs[] = {
1022 &dev_attr_fan1_input.attr,
1023 &dev_attr_fan1_alarm.attr,
1024 &dev_attr_fan1_fault.attr,
1025 &dev_attr_fan1_target.attr,
1026 &dev_attr_fan1_div.attr,
1027 &dev_attr_fan1_pulses.attr,
1028 &dev_attr_pwm1.attr,
1029 &dev_attr_pwm1_mode.attr,
1030 &dev_attr_pwm1_enable.attr,
1031 NULL
1032};
1033
1034ATTRIBUTE_GROUPS(g762);
1035
1036/*
1037 * Enable both fan failure detection and fan out of control protection. The
1038 * function does not protect change/access to data structure; it must thus
1039 * only be called during initialization.
1040 */
1041static inline int g762_fan_init(struct device *dev)
1042{
1043 struct g762_data *data = g762_update_client(dev);
1044
1045 if (IS_ERR(data))
1046 return PTR_ERR(data);
1047
1048 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL;
1049 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC;
1050 data->valid = false;
1051
1052 return i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
1053 data->fan_cmd1);
1054}
1055
1056static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id)
1057{
1058 struct device *dev = &client->dev;
1059 struct g762_data *data;
1060 int ret;
1061
1062 if (!i2c_check_functionality(client->adapter,
1063 I2C_FUNC_SMBUS_BYTE_DATA))
1064 return -ENODEV;
1065
1066 data = devm_kzalloc(dev, sizeof(struct g762_data), GFP_KERNEL);
1067 if (!data)
1068 return -ENOMEM;
1069
1070 i2c_set_clientdata(client, data);
1071 data->client = client;
1072 mutex_init(&data->update_lock);
1073
1074 /* Enable fan failure detection and fan out of control protection */
1075 ret = g762_fan_init(dev);
1076 if (ret)
1077 return ret;
1078
1079 /* Get configuration via DT ... */
1080 ret = g762_of_clock_enable(client);
1081 if (ret)
1082 return ret;
1083 ret = g762_of_prop_import(client);
1084 if (ret)
1085 goto clock_dis;
1086 /* ... or platform_data */
1087 ret = g762_pdata_prop_import(client);
1088 if (ret)
1089 goto clock_dis;
1090
1091 data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
1092 data, g762_groups);
1093 if (IS_ERR(data->hwmon_dev)) {
1094 ret = PTR_ERR(data->hwmon_dev);
1095 goto clock_dis;
1096 }
1097
1098 return 0;
1099
1100 clock_dis:
1101 g762_of_clock_disable(client);
1102
1103 return ret;
1104}
1105
1106static int g762_remove(struct i2c_client *client)
1107{
1108 struct g762_data *data = i2c_get_clientdata(client);
1109
1110 hwmon_device_unregister(data->hwmon_dev);
1111 g762_of_clock_disable(client);
1112
1113 return 0;
1114}
1115
1116static struct i2c_driver g762_driver = {
1117 .driver = {
1118 .name = DRVNAME,
1119 .of_match_table = of_match_ptr(g762_dt_match),
1120 },
1121 .probe = g762_probe,
1122 .remove = g762_remove,
1123 .id_table = g762_id,
1124};
1125
1126module_i2c_driver(g762_driver);
1127
1128MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>");
1129MODULE_DESCRIPTION("GMT G762/G763 driver");
1130MODULE_LICENSE("GPL");
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
47static const struct i2c_device_id g762_id[] = {
48 { "g762", 0 },
49 { "g763", 0 },
50 { }
51};
52MODULE_DEVICE_TABLE(i2c, g762_id);
53
54enum 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
117struct 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 */
169static 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 */
182static 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 */
196static 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 */
256static 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) */
271static 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. */
301static 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. */
341static 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. */
377static 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). */
407static 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) */
448static 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 */
481static 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 */
502static 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. */
524static 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
569static const struct of_device_id g762_dt_match[] = {
570 { .compatible = "gmt,g762" },
571 { .compatible = "gmt,g763" },
572 { },
573};
574MODULE_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 */
583static 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
591static 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
635static 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
654static 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
676static int g762_of_prop_import(struct i2c_client *client)
677{
678 return 0;
679}
680
681static 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
692static 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 */
723static 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 */
749static 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
761static 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 */
782static 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
793static 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 */
813static 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
824static 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 */
855static 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
867static 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 */
889static 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
900static 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 */
927static 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
946static 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. */
964static 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 */
979static 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
990static DEVICE_ATTR_RW(pwm1);
991static DEVICE_ATTR_RW(pwm1_mode);
992static DEVICE_ATTR_RW(pwm1_enable);
993static DEVICE_ATTR_RO(fan1_input);
994static DEVICE_ATTR_RO(fan1_alarm);
995static DEVICE_ATTR_RO(fan1_fault);
996static DEVICE_ATTR_RW(fan1_target);
997static DEVICE_ATTR_RW(fan1_div);
998static DEVICE_ATTR_RW(fan1_pulses);
999
1000/* Driver data */
1001static 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
1014ATTRIBUTE_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 */
1021static 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
1036static int g762_probe(struct i2c_client *client)
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
1077static struct i2c_driver g762_driver = {
1078 .driver = {
1079 .name = DRVNAME,
1080 .of_match_table = of_match_ptr(g762_dt_match),
1081 },
1082 .probe_new = g762_probe,
1083 .id_table = g762_id,
1084};
1085
1086module_i2c_driver(g762_driver);
1087
1088MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>");
1089MODULE_DESCRIPTION("GMT G762/G763 driver");
1090MODULE_LICENSE("GPL");