Loading...
Note: File does not exist in v3.1.
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 i2c_client *client;
132 struct device *hwmon_dev;
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(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 */
207static struct g762_data *g762_update_client(struct device *dev)
208{
209 struct i2c_client *client = to_i2c_client(dev);
210 struct g762_data *data = i2c_get_clientdata(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 */
267static int do_set_clk_freq(struct device *dev, unsigned long val)
268{
269 struct i2c_client *client = to_i2c_client(dev);
270 struct g762_data *data = i2c_get_clientdata(client);
271
272 if (val > 0xffffff)
273 return -EINVAL;
274 if (!val)
275 val = 32768;
276
277 data->clk_freq = val;
278
279 return 0;
280}
281
282/* Set pwm mode. Accepts either 0 (PWM mode) or 1 (DC mode) */
283static int do_set_pwm_mode(struct device *dev, unsigned long val)
284{
285 struct i2c_client *client = to_i2c_client(dev);
286 struct g762_data *data = g762_update_client(dev);
287 int ret;
288
289 if (IS_ERR(data))
290 return PTR_ERR(data);
291
292 mutex_lock(&data->update_lock);
293 switch (val) {
294 case G762_OUT_MODE_PWM:
295 data->fan_cmd1 |= G762_REG_FAN_CMD1_OUT_MODE;
296 break;
297 case G762_OUT_MODE_DC:
298 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_OUT_MODE;
299 break;
300 default:
301 ret = -EINVAL;
302 goto out;
303 }
304 ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1,
305 data->fan_cmd1);
306 data->valid = false;
307 out:
308 mutex_unlock(&data->update_lock);
309
310 return ret;
311}
312
313/* Set fan clock divisor. Accepts either 1, 2, 4 or 8. */
314static int do_set_fan_div(struct device *dev, unsigned long val)
315{
316 struct i2c_client *client = to_i2c_client(dev);
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(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 i2c_client *client = to_i2c_client(dev);
358 struct g762_data *data = g762_update_client(dev);
359 int ret;
360
361 if (IS_ERR(data))
362 return PTR_ERR(data);
363
364 mutex_lock(&data->update_lock);
365 switch (val) {
366 case 0:
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 1:
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 case 2:
375 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0;
376 data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_1;
377 break;
378 default:
379 ret = -EINVAL;
380 goto out;
381 }
382 ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD2,
383 data->fan_cmd2);
384 data->valid = false;
385 out:
386 mutex_unlock(&data->update_lock);
387
388 return ret;
389}
390
391/* Set number of fan pulses per revolution. Accepts either 2 or 4. */
392static int do_set_fan_pulses(struct device *dev, unsigned long val)
393{
394 struct i2c_client *client = to_i2c_client(dev);
395 struct g762_data *data = g762_update_client(dev);
396 int ret;
397
398 if (IS_ERR(data))
399 return PTR_ERR(data);
400
401 mutex_lock(&data->update_lock);
402 switch (val) {
403 case 2:
404 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PULSE_PER_REV;
405 break;
406 case 4:
407 data->fan_cmd1 |= G762_REG_FAN_CMD1_PULSE_PER_REV;
408 break;
409 default:
410 ret = -EINVAL;
411 goto out;
412 }
413 ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1,
414 data->fan_cmd1);
415 data->valid = false;
416 out:
417 mutex_unlock(&data->update_lock);
418
419 return ret;
420}
421
422/* Set fan mode. Accepts either 1 (open-loop) or 2 (closed-loop). */
423static int do_set_pwm_enable(struct device *dev, unsigned long val)
424{
425 struct i2c_client *client = to_i2c_client(dev);
426 struct g762_data *data = g762_update_client(dev);
427 int ret;
428
429 if (IS_ERR(data))
430 return PTR_ERR(data);
431
432 mutex_lock(&data->update_lock);
433 switch (val) {
434 case G762_FAN_MODE_CLOSED_LOOP:
435 data->fan_cmd1 |= G762_REG_FAN_CMD1_FAN_MODE;
436 break;
437 case G762_FAN_MODE_OPEN_LOOP:
438 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_FAN_MODE;
439 /*
440 * BUG FIX: if SET_CNT register value is 255 then, for some
441 * unknown reason, fan will not rotate as expected, no matter
442 * the value of SET_OUT (to be specific, this seems to happen
443 * only in PWM mode). To workaround this bug, we give SET_CNT
444 * value of 254 if it is 255 when switching to open-loop.
445 */
446 if (data->set_cnt == 0xff)
447 i2c_smbus_write_byte_data(client, G762_REG_SET_CNT,
448 254);
449 break;
450 default:
451 ret = -EINVAL;
452 goto out;
453 }
454
455 ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1,
456 data->fan_cmd1);
457 data->valid = false;
458 out:
459 mutex_unlock(&data->update_lock);
460
461 return ret;
462}
463
464/* Set PWM polarity. Accepts either 0 (positive duty) or 1 (negative duty) */
465static int do_set_pwm_polarity(struct device *dev, unsigned long val)
466{
467 struct i2c_client *client = to_i2c_client(dev);
468 struct g762_data *data = g762_update_client(dev);
469 int ret;
470
471 if (IS_ERR(data))
472 return PTR_ERR(data);
473
474 mutex_lock(&data->update_lock);
475 switch (val) {
476 case G762_PWM_POLARITY_POSITIVE:
477 data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PWM_POLARITY;
478 break;
479 case G762_PWM_POLARITY_NEGATIVE:
480 data->fan_cmd1 |= G762_REG_FAN_CMD1_PWM_POLARITY;
481 break;
482 default:
483 ret = -EINVAL;
484 goto out;
485 }
486 ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1,
487 data->fan_cmd1);
488 data->valid = false;
489 out:
490 mutex_unlock(&data->update_lock);
491
492 return ret;
493}
494
495/*
496 * Set pwm value. Accepts values between 0 (stops the fan) and
497 * 255 (full speed). This only makes sense in open-loop mode.
498 */
499static int do_set_pwm(struct device *dev, unsigned long val)
500{
501 struct i2c_client *client = to_i2c_client(dev);
502 struct g762_data *data = i2c_get_clientdata(client);
503 int ret;
504
505 if (val > 255)
506 return -EINVAL;
507
508 mutex_lock(&data->update_lock);
509 ret = i2c_smbus_write_byte_data(client, G762_REG_SET_OUT, val);
510 data->valid = false;
511 mutex_unlock(&data->update_lock);
512
513 return ret;
514}
515
516/*
517 * Set fan RPM value. Can be called both in closed and open-loop mode
518 * but effect will only be seen after closed-loop mode is configured.
519 */
520static int do_set_fan_target(struct device *dev, unsigned long val)
521{
522 struct i2c_client *client = to_i2c_client(dev);
523 struct g762_data *data = g762_update_client(dev);
524 int ret;
525
526 if (IS_ERR(data))
527 return PTR_ERR(data);
528
529 mutex_lock(&data->update_lock);
530 data->set_cnt = cnt_from_rpm(val, data->clk_freq,
531 G762_PULSE_FROM_REG(data->fan_cmd1),
532 G762_CLKDIV_FROM_REG(data->fan_cmd1),
533 G762_GEARMULT_FROM_REG(data->fan_cmd2));
534 ret = i2c_smbus_write_byte_data(client, G762_REG_SET_CNT,
535 data->set_cnt);
536 data->valid = false;
537 mutex_unlock(&data->update_lock);
538
539 return ret;
540}
541
542/* Set fan startup voltage. Accepted values are either 0, 1, 2 or 3. */
543static int do_set_fan_startv(struct device *dev, unsigned long val)
544{
545 struct i2c_client *client = to_i2c_client(dev);
546 struct g762_data *data = g762_update_client(dev);
547 int ret;
548
549 if (IS_ERR(data))
550 return PTR_ERR(data);
551
552 mutex_lock(&data->update_lock);
553 switch (val) {
554 case 0:
555 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0;
556 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1;
557 break;
558 case 1:
559 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0;
560 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1;
561 break;
562 case 2:
563 data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0;
564 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1;
565 break;
566 case 3:
567 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0;
568 data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1;
569 break;
570 default:
571 ret = -EINVAL;
572 goto out;
573 }
574 ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD2,
575 data->fan_cmd2);
576 data->valid = false;
577 out:
578 mutex_unlock(&data->update_lock);
579
580 return ret;
581}
582
583/*
584 * Helper to import hardware characteristics from .dts file and push
585 * those to the chip.
586 */
587
588#ifdef CONFIG_OF
589static struct of_device_id g762_dt_match[] = {
590 { .compatible = "gmt,g762" },
591 { .compatible = "gmt,g763" },
592 { },
593};
594
595/*
596 * Grab clock (a required property), enable it, get (fixed) clock frequency
597 * and store it. Note: upon success, clock has been prepared and enabled; it
598 * must later be unprepared and disabled (e.g. during module unloading) by a
599 * call to g762_of_clock_disable(). Note that a reference to clock is kept
600 * in our private data structure to be used in this function.
601 */
602static int g762_of_clock_enable(struct i2c_client *client)
603{
604 struct g762_data *data;
605 unsigned long clk_freq;
606 struct clk *clk;
607 int ret;
608
609 if (!client->dev.of_node)
610 return 0;
611
612 clk = of_clk_get(client->dev.of_node, 0);
613 if (IS_ERR(clk)) {
614 dev_err(&client->dev, "failed to get clock\n");
615 return PTR_ERR(clk);
616 }
617
618 ret = clk_prepare_enable(clk);
619 if (ret) {
620 dev_err(&client->dev, "failed to enable clock\n");
621 goto clk_put;
622 }
623
624 clk_freq = clk_get_rate(clk);
625 ret = do_set_clk_freq(&client->dev, clk_freq);
626 if (ret) {
627 dev_err(&client->dev, "invalid clock freq %lu\n", clk_freq);
628 goto clk_unprep;
629 }
630
631 data = i2c_get_clientdata(client);
632 data->clk = clk;
633
634 return 0;
635
636 clk_unprep:
637 clk_disable_unprepare(clk);
638
639 clk_put:
640 clk_put(clk);
641
642 return ret;
643}
644
645static void g762_of_clock_disable(struct i2c_client *client)
646{
647 struct g762_data *data = i2c_get_clientdata(client);
648
649 if (!data->clk)
650 return;
651
652 clk_disable_unprepare(data->clk);
653 clk_put(data->clk);
654}
655
656static int g762_of_prop_import_one(struct i2c_client *client,
657 const char *pname,
658 int (*psetter)(struct device *dev,
659 unsigned long val))
660{
661 const __be32 *prop;
662 int len, ret;
663 u32 pval;
664
665 prop = of_get_property(client->dev.of_node, pname, &len);
666 if (!prop || len != sizeof(u32))
667 return 0;
668
669 pval = be32_to_cpu(prop[0]);
670 dev_dbg(&client->dev, "found %s (%d)\n", pname, pval);
671 ret = (*psetter)(&client->dev, pval);
672 if (ret)
673 dev_err(&client->dev, "unable to set %s (%d)\n", pname, pval);
674
675 return ret;
676}
677
678static int g762_of_prop_import(struct i2c_client *client)
679{
680 int ret;
681
682 if (!client->dev.of_node)
683 return 0;
684
685 ret = g762_of_prop_import_one(client, "fan_gear_mode",
686 do_set_fan_gear_mode);
687 if (ret)
688 return ret;
689
690 ret = g762_of_prop_import_one(client, "pwm_polarity",
691 do_set_pwm_polarity);
692 if (ret)
693 return ret;
694
695 return g762_of_prop_import_one(client, "fan_startv",
696 do_set_fan_startv);
697}
698
699#else
700static int g762_of_prop_import(struct i2c_client *client)
701{
702 return 0;
703}
704
705static int g762_of_clock_enable(struct i2c_client *client)
706{
707 return 0;
708}
709
710static void g762_of_clock_disable(struct i2c_client *client) { }
711#endif
712
713/*
714 * Helper to import hardware characteristics from .dts file and push
715 * those to the chip.
716 */
717
718static int g762_pdata_prop_import(struct i2c_client *client)
719{
720 struct g762_platform_data *pdata = dev_get_platdata(&client->dev);
721 int ret;
722
723 if (!pdata)
724 return 0;
725
726 ret = do_set_fan_gear_mode(&client->dev, pdata->fan_gear_mode);
727 if (ret)
728 return ret;
729
730 ret = do_set_pwm_polarity(&client->dev, pdata->pwm_polarity);
731 if (ret)
732 return ret;
733
734 ret = do_set_fan_startv(&client->dev, pdata->fan_startv);
735 if (ret)
736 return ret;
737
738 return do_set_clk_freq(&client->dev, pdata->clk_freq);
739}
740
741/*
742 * sysfs attributes
743 */
744
745/*
746 * Read function for fan1_input sysfs file. Return current fan RPM value, or
747 * 0 if fan is out of control.
748 */
749static ssize_t get_fan_rpm(struct device *dev, struct device_attribute *da,
750 char *buf)
751{
752 struct g762_data *data = g762_update_client(dev);
753 unsigned int rpm = 0;
754
755 if (IS_ERR(data))
756 return PTR_ERR(data);
757
758 mutex_lock(&data->update_lock);
759 /* reverse logic: fan out of control reporting is enabled low */
760 if (data->fan_sta & G762_REG_FAN_STA_OOC) {
761 rpm = rpm_from_cnt(data->act_cnt, data->clk_freq,
762 G762_PULSE_FROM_REG(data->fan_cmd1),
763 G762_CLKDIV_FROM_REG(data->fan_cmd1),
764 G762_GEARMULT_FROM_REG(data->fan_cmd2));
765 }
766 mutex_unlock(&data->update_lock);
767
768 return sprintf(buf, "%u\n", rpm);
769}
770
771/*
772 * Read and write functions for pwm1_mode sysfs file. Get and set fan speed
773 * control mode i.e. PWM (1) or DC (0).
774 */
775static ssize_t get_pwm_mode(struct device *dev, struct device_attribute *da,
776 char *buf)
777{
778 struct g762_data *data = g762_update_client(dev);
779
780 if (IS_ERR(data))
781 return PTR_ERR(data);
782
783 return sprintf(buf, "%d\n",
784 !!(data->fan_cmd1 & G762_REG_FAN_CMD1_OUT_MODE));
785}
786
787static ssize_t set_pwm_mode(struct device *dev, struct device_attribute *da,
788 const char *buf, size_t count)
789{
790 unsigned long val;
791 int ret;
792
793 if (kstrtoul(buf, 10, &val))
794 return -EINVAL;
795
796 ret = do_set_pwm_mode(dev, val);
797 if (ret < 0)
798 return ret;
799
800 return count;
801}
802
803/*
804 * Read and write functions for fan1_div sysfs file. Get and set fan
805 * controller prescaler value
806 */
807static ssize_t get_fan_div(struct device *dev,
808 struct device_attribute *da, char *buf)
809{
810 struct g762_data *data = g762_update_client(dev);
811
812 if (IS_ERR(data))
813 return PTR_ERR(data);
814
815 return sprintf(buf, "%d\n", G762_CLKDIV_FROM_REG(data->fan_cmd1));
816}
817
818static ssize_t set_fan_div(struct device *dev,
819 struct device_attribute *da,
820 const char *buf, size_t count)
821{
822 unsigned long val;
823 int ret;
824
825 if (kstrtoul(buf, 10, &val))
826 return -EINVAL;
827
828 ret = do_set_fan_div(dev, val);
829 if (ret < 0)
830 return ret;
831
832 return count;
833}
834
835/*
836 * Read and write functions for fan1_pulses sysfs file. Get and set number
837 * of tachometer pulses per fan revolution.
838 */
839static ssize_t get_fan_pulses(struct device *dev,
840 struct device_attribute *da, char *buf)
841{
842 struct g762_data *data = g762_update_client(dev);
843
844 if (IS_ERR(data))
845 return PTR_ERR(data);
846
847 return sprintf(buf, "%d\n", G762_PULSE_FROM_REG(data->fan_cmd1));
848}
849
850static ssize_t set_fan_pulses(struct device *dev,
851 struct device_attribute *da,
852 const char *buf, size_t count)
853{
854 unsigned long val;
855 int ret;
856
857 if (kstrtoul(buf, 10, &val))
858 return -EINVAL;
859
860 ret = do_set_fan_pulses(dev, val);
861 if (ret < 0)
862 return ret;
863
864 return count;
865}
866
867/*
868 * Read and write functions for pwm1_enable. Get and set fan speed control mode
869 * (i.e. closed or open-loop).
870 *
871 * Following documentation about hwmon's sysfs interface, a pwm1_enable node
872 * should accept followings:
873 *
874 * 0 : no fan speed control (i.e. fan at full speed)
875 * 1 : manual fan speed control enabled (use pwm[1-*]) (open-loop)
876 * 2+: automatic fan speed control enabled (use fan[1-*]_target) (closed-loop)
877 *
878 * but we do not accept 0 as this mode is not natively supported by the chip
879 * and it is not emulated by g762 driver. -EINVAL is returned in this case.
880 */
881static ssize_t get_pwm_enable(struct device *dev,
882 struct device_attribute *da, char *buf)
883{
884 struct g762_data *data = g762_update_client(dev);
885
886 if (IS_ERR(data))
887 return PTR_ERR(data);
888
889 return sprintf(buf, "%d\n",
890 (!!(data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE)) + 1);
891}
892
893static ssize_t set_pwm_enable(struct device *dev,
894 struct device_attribute *da,
895 const char *buf, size_t count)
896{
897 unsigned long val;
898 int ret;
899
900 if (kstrtoul(buf, 10, &val))
901 return -EINVAL;
902
903 ret = do_set_pwm_enable(dev, val);
904 if (ret < 0)
905 return ret;
906
907 return count;
908}
909
910/*
911 * Read and write functions for pwm1 sysfs file. Get and set pwm value
912 * (which affects fan speed) in open-loop mode. 0 stops the fan and 255
913 * makes it run at full speed.
914 */
915static ssize_t get_pwm(struct device *dev, struct device_attribute *da,
916 char *buf)
917{
918 struct g762_data *data = g762_update_client(dev);
919
920 if (IS_ERR(data))
921 return PTR_ERR(data);
922
923 return sprintf(buf, "%d\n", data->set_out);
924}
925
926static ssize_t set_pwm(struct device *dev, struct device_attribute *da,
927 const char *buf, size_t count)
928{
929 unsigned long val;
930 int ret;
931
932 if (kstrtoul(buf, 10, &val))
933 return -EINVAL;
934
935 ret = do_set_pwm(dev, val);
936 if (ret < 0)
937 return ret;
938
939 return count;
940}
941
942/*
943 * Read and write function for fan1_target sysfs file. Get/set the fan speed in
944 * closed-loop mode. Speed is given as a RPM value; then the chip will regulate
945 * the fan speed using pulses from fan tachometer.
946 *
947 * Refer to rpm_from_cnt() implementation above to get info about count number
948 * calculation.
949 *
950 * Also note that due to rounding errors it is possible that you don't read
951 * back exactly the value you have set.
952 */
953static ssize_t get_fan_target(struct device *dev, struct device_attribute *da,
954 char *buf)
955{
956 struct g762_data *data = g762_update_client(dev);
957 unsigned int rpm;
958
959 if (IS_ERR(data))
960 return PTR_ERR(data);
961
962 mutex_lock(&data->update_lock);
963 rpm = rpm_from_cnt(data->set_cnt, data->clk_freq,
964 G762_PULSE_FROM_REG(data->fan_cmd1),
965 G762_CLKDIV_FROM_REG(data->fan_cmd1),
966 G762_GEARMULT_FROM_REG(data->fan_cmd2));
967 mutex_unlock(&data->update_lock);
968
969 return sprintf(buf, "%u\n", rpm);
970}
971
972static ssize_t set_fan_target(struct device *dev, struct device_attribute *da,
973 const char *buf, size_t count)
974{
975 unsigned long val;
976 int ret;
977
978 if (kstrtoul(buf, 10, &val))
979 return -EINVAL;
980
981 ret = do_set_fan_target(dev, val);
982 if (ret < 0)
983 return ret;
984
985 return count;
986}
987
988/* read function for fan1_fault sysfs file. */
989static ssize_t get_fan_failure(struct device *dev, struct device_attribute *da,
990 char *buf)
991{
992 struct g762_data *data = g762_update_client(dev);
993
994 if (IS_ERR(data))
995 return PTR_ERR(data);
996
997 return sprintf(buf, "%u\n", !!(data->fan_sta & G762_REG_FAN_STA_FAIL));
998}
999
1000/*
1001 * read function for fan1_alarm sysfs file. Note that OOC condition is
1002 * enabled low
1003 */
1004static ssize_t get_fan_ooc(struct device *dev, struct device_attribute *da,
1005 char *buf)
1006{
1007 struct g762_data *data = g762_update_client(dev);
1008
1009 if (IS_ERR(data))
1010 return PTR_ERR(data);
1011
1012 return sprintf(buf, "%u\n", !(data->fan_sta & G762_REG_FAN_STA_OOC));
1013}
1014
1015static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
1016static DEVICE_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, get_pwm_mode, set_pwm_mode);
1017static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO,
1018 get_pwm_enable, set_pwm_enable);
1019static DEVICE_ATTR(fan1_input, S_IRUGO, get_fan_rpm, NULL);
1020static DEVICE_ATTR(fan1_alarm, S_IRUGO, get_fan_ooc, NULL);
1021static DEVICE_ATTR(fan1_fault, S_IRUGO, get_fan_failure, NULL);
1022static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO,
1023 get_fan_target, set_fan_target);
1024static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_fan_div, set_fan_div);
1025static DEVICE_ATTR(fan1_pulses, S_IWUSR | S_IRUGO,
1026 get_fan_pulses, set_fan_pulses);
1027
1028/* Driver data */
1029static struct attribute *g762_attributes[] = {
1030 &dev_attr_fan1_input.attr,
1031 &dev_attr_fan1_alarm.attr,
1032 &dev_attr_fan1_fault.attr,
1033 &dev_attr_fan1_target.attr,
1034 &dev_attr_fan1_div.attr,
1035 &dev_attr_fan1_pulses.attr,
1036 &dev_attr_pwm1.attr,
1037 &dev_attr_pwm1_mode.attr,
1038 &dev_attr_pwm1_enable.attr,
1039 NULL
1040};
1041
1042static const struct attribute_group g762_group = {
1043 .attrs = g762_attributes,
1044};
1045
1046/*
1047 * Enable both fan failure detection and fan out of control protection. The
1048 * function does not protect change/access to data structure; it must thus
1049 * only be called during initialization.
1050 */
1051static inline int g762_fan_init(struct device *dev)
1052{
1053 struct i2c_client *client = to_i2c_client(dev);
1054 struct g762_data *data = g762_update_client(dev);
1055
1056 if (IS_ERR(data))
1057 return PTR_ERR(data);
1058
1059 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL;
1060 data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC;
1061 data->valid = false;
1062
1063 return i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1,
1064 data->fan_cmd1);
1065}
1066
1067static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id)
1068{
1069 struct g762_data *data;
1070 int ret;
1071
1072 if (!i2c_check_functionality(client->adapter,
1073 I2C_FUNC_SMBUS_BYTE_DATA))
1074 return -ENODEV;
1075
1076 data = devm_kzalloc(&client->dev, sizeof(struct g762_data), GFP_KERNEL);
1077 if (!data)
1078 return -ENOMEM;
1079
1080 i2c_set_clientdata(client, data);
1081 data->client = client;
1082 mutex_init(&data->update_lock);
1083
1084 /* Enable fan failure detection and fan out of control protection */
1085 ret = g762_fan_init(&client->dev);
1086 if (ret)
1087 return ret;
1088
1089 /* Get configuration via DT ... */
1090 ret = g762_of_clock_enable(client);
1091 if (ret)
1092 return ret;
1093 ret = g762_of_prop_import(client);
1094 if (ret)
1095 goto clock_dis;
1096 /* ... or platform_data */
1097 ret = g762_pdata_prop_import(client);
1098 if (ret)
1099 goto clock_dis;
1100
1101 /* Register sysfs hooks */
1102 ret = sysfs_create_group(&client->dev.kobj, &g762_group);
1103 if (ret)
1104 goto clock_dis;
1105
1106 data->hwmon_dev = hwmon_device_register(&client->dev);
1107 if (IS_ERR(data->hwmon_dev)) {
1108 ret = PTR_ERR(data->hwmon_dev);
1109 goto sysfs_rem;
1110 }
1111
1112 return 0;
1113
1114 sysfs_rem:
1115 sysfs_remove_group(&client->dev.kobj, &g762_group);
1116
1117 clock_dis:
1118 g762_of_clock_disable(client);
1119
1120 return ret;
1121}
1122
1123static int g762_remove(struct i2c_client *client)
1124{
1125 struct g762_data *data = i2c_get_clientdata(client);
1126
1127 hwmon_device_unregister(data->hwmon_dev);
1128 sysfs_remove_group(&client->dev.kobj, &g762_group);
1129 g762_of_clock_disable(client);
1130
1131 return 0;
1132}
1133
1134static struct i2c_driver g762_driver = {
1135 .driver = {
1136 .name = DRVNAME,
1137 .owner = THIS_MODULE,
1138 .of_match_table = of_match_ptr(g762_dt_match),
1139 },
1140 .probe = g762_probe,
1141 .remove = g762_remove,
1142 .id_table = g762_id,
1143};
1144
1145module_i2c_driver(g762_driver);
1146
1147MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>");
1148MODULE_DESCRIPTION("GMT G762/G763 driver");
1149MODULE_LICENSE("GPL");