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