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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Analog Devices LTC4282 I2C High Current Hot Swap Controller over I2C
4 *
5 * Copyright 2023 Analog Devices Inc.
6 */
7#include <linux/bitfield.h>
8#include <linux/cleanup.h>
9#include <linux/clk.h>
10#include <linux/clk-provider.h>
11#include <linux/debugfs.h>
12#include <linux/delay.h>
13#include <linux/device.h>
14#include <linux/hwmon.h>
15#include <linux/hwmon-sysfs.h>
16#include <linux/i2c.h>
17#include <linux/math.h>
18#include <linux/minmax.h>
19#include <linux/module.h>
20#include <linux/mod_devicetable.h>
21#include <linux/mutex.h>
22#include <linux/regmap.h>
23#include <linux/property.h>
24#include <linux/string.h>
25#include <linux/units.h>
26#include <linux/util_macros.h>
27
28#define LTC4282_CTRL_LSB 0x00
29 #define LTC4282_CTRL_OV_RETRY_MASK BIT(0)
30 #define LTC4282_CTRL_UV_RETRY_MASK BIT(1)
31 #define LTC4282_CTRL_OC_RETRY_MASK BIT(2)
32 #define LTC4282_CTRL_ON_ACTIVE_LOW_MASK BIT(5)
33 #define LTC4282_CTRL_ON_DELAY_MASK BIT(6)
34#define LTC4282_CTRL_MSB 0x01
35 #define LTC4282_CTRL_VIN_MODE_MASK GENMASK(1, 0)
36 #define LTC4282_CTRL_OV_MODE_MASK GENMASK(3, 2)
37 #define LTC4282_CTRL_UV_MODE_MASK GENMASK(5, 4)
38#define LTC4282_FAULT_LOG 0x04
39 #define LTC4282_OV_FAULT_MASK BIT(0)
40 #define LTC4282_UV_FAULT_MASK BIT(1)
41 #define LTC4282_VDD_FAULT_MASK \
42 (LTC4282_OV_FAULT_MASK | LTC4282_UV_FAULT_MASK)
43 #define LTC4282_OC_FAULT_MASK BIT(2)
44 #define LTC4282_POWER_BAD_FAULT_MASK BIT(3)
45 #define LTC4282_FET_SHORT_FAULT_MASK BIT(5)
46 #define LTC4282_FET_BAD_FAULT_MASK BIT(6)
47 #define LTC4282_FET_FAILURE_FAULT_MASK \
48 (LTC4282_FET_SHORT_FAULT_MASK | LTC4282_FET_BAD_FAULT_MASK)
49#define LTC4282_ADC_ALERT_LOG 0x05
50 #define LTC4282_GPIO_ALARM_L_MASK BIT(0)
51 #define LTC4282_GPIO_ALARM_H_MASK BIT(1)
52 #define LTC4282_VSOURCE_ALARM_L_MASK BIT(2)
53 #define LTC4282_VSOURCE_ALARM_H_MASK BIT(3)
54 #define LTC4282_VSENSE_ALARM_L_MASK BIT(4)
55 #define LTC4282_VSENSE_ALARM_H_MASK BIT(5)
56 #define LTC4282_POWER_ALARM_L_MASK BIT(6)
57 #define LTC4282_POWER_ALARM_H_MASK BIT(7)
58#define LTC4282_FET_BAD_FAULT_TIMEOUT 0x06
59 #define LTC4282_FET_BAD_MAX_TIMEOUT 255
60#define LTC4282_GPIO_CONFIG 0x07
61 #define LTC4282_GPIO_2_FET_STRESS_MASK BIT(1)
62 #define LTC4282_GPIO_1_CONFIG_MASK GENMASK(5, 4)
63#define LTC4282_VGPIO_MIN 0x08
64#define LTC4282_VGPIO_MAX 0x09
65#define LTC4282_VSOURCE_MIN 0x0a
66#define LTC4282_VSOURCE_MAX 0x0b
67#define LTC4282_VSENSE_MIN 0x0c
68#define LTC4282_VSENSE_MAX 0x0d
69#define LTC4282_POWER_MIN 0x0e
70#define LTC4282_POWER_MAX 0x0f
71#define LTC4282_CLK_DIV 0x10
72 #define LTC4282_CLK_DIV_MASK GENMASK(4, 0)
73 #define LTC4282_CLKOUT_MASK GENMASK(6, 5)
74#define LTC4282_ILIM_ADJUST 0x11
75 #define LTC4282_GPIO_MODE_MASK BIT(1)
76 #define LTC4282_VDD_MONITOR_MASK BIT(2)
77 #define LTC4282_FOLDBACK_MODE_MASK GENMASK(4, 3)
78 #define LTC4282_ILIM_ADJUST_MASK GENMASK(7, 5)
79#define LTC4282_ENERGY 0x12
80#define LTC4282_TIME_COUNTER 0x18
81#define LTC4282_ALERT_CTRL 0x1c
82 #define LTC4282_ALERT_OUT_MASK BIT(6)
83#define LTC4282_ADC_CTRL 0x1d
84 #define LTC4282_FAULT_LOG_EN_MASK BIT(2)
85 #define LTC4282_METER_HALT_MASK BIT(5)
86 #define LTC4282_METER_RESET_MASK BIT(6)
87 #define LTC4282_RESET_MASK BIT(7)
88#define LTC4282_STATUS_LSB 0x1e
89 #define LTC4282_OV_STATUS_MASK BIT(0)
90 #define LTC4282_UV_STATUS_MASK BIT(1)
91 #define LTC4282_VDD_STATUS_MASK \
92 (LTC4282_OV_STATUS_MASK | LTC4282_UV_STATUS_MASK)
93 #define LTC4282_OC_STATUS_MASK BIT(2)
94 #define LTC4282_POWER_GOOD_MASK BIT(3)
95 #define LTC4282_FET_FAILURE_MASK GENMASK(6, 5)
96#define LTC4282_STATUS_MSB 0x1f
97#define LTC4282_RESERVED_1 0x32
98#define LTC4282_RESERVED_2 0x33
99#define LTC4282_VGPIO 0x34
100#define LTC4282_VGPIO_LOWEST 0x36
101#define LTC4282_VGPIO_HIGHEST 0x38
102#define LTC4282_VSOURCE 0x3a
103#define LTC4282_VSOURCE_LOWEST 0x3c
104#define LTC4282_VSOURCE_HIGHEST 0x3e
105#define LTC4282_VSENSE 0x40
106#define LTC4282_VSENSE_LOWEST 0x42
107#define LTC4282_VSENSE_HIGHEST 0x44
108#define LTC4282_POWER 0x46
109#define LTC4282_POWER_LOWEST 0x48
110#define LTC4282_POWER_HIGHEST 0x4a
111#define LTC4282_RESERVED_3 0x50
112
113#define LTC4282_CLKIN_MIN (250 * KILO)
114#define LTC4282_CLKIN_MAX (15500 * KILO)
115#define LTC4282_CLKIN_RANGE (LTC4282_CLKIN_MAX - LTC4282_CLKIN_MIN + 1)
116#define LTC4282_CLKOUT_SYSTEM (250 * KILO)
117#define LTC4282_CLKOUT_CNV 15
118
119enum {
120 LTC4282_CHAN_VSOURCE,
121 LTC4282_CHAN_VDD,
122 LTC4282_CHAN_VGPIO,
123};
124
125struct ltc4282_cache {
126 u32 in_max_raw;
127 u32 in_min_raw;
128 long in_highest;
129 long in_lowest;
130 bool en;
131};
132
133struct ltc4282_state {
134 struct regmap *map;
135 /* Protect against multiple accesses to the device registers */
136 struct mutex lock;
137 struct clk_hw clk_hw;
138 /*
139 * Used to cache values for VDD/VSOURCE depending which will be used
140 * when hwmon is not enabled for that channel. Needed because they share
141 * the same registers.
142 */
143 struct ltc4282_cache in0_1_cache[LTC4282_CHAN_VGPIO];
144 u32 vsense_max;
145 long power_max;
146 u32 rsense;
147 u16 vdd;
148 u16 vfs_out;
149 bool energy_en;
150};
151
152enum {
153 LTC4282_CLKOUT_NONE,
154 LTC4282_CLKOUT_INT,
155 LTC4282_CLKOUT_TICK,
156};
157
158static int ltc4282_set_rate(struct clk_hw *hw,
159 unsigned long rate, unsigned long parent_rate)
160{
161 struct ltc4282_state *st = container_of(hw, struct ltc4282_state,
162 clk_hw);
163 u32 val = LTC4282_CLKOUT_INT;
164
165 if (rate == LTC4282_CLKOUT_CNV)
166 val = LTC4282_CLKOUT_TICK;
167
168 return regmap_update_bits(st->map, LTC4282_CLK_DIV, LTC4282_CLKOUT_MASK,
169 FIELD_PREP(LTC4282_CLKOUT_MASK, val));
170}
171
172/*
173 * Note the 15HZ conversion rate assumes 12bit ADC which is what we are
174 * supporting for now.
175 */
176static const unsigned int ltc4282_out_rates[] = {
177 LTC4282_CLKOUT_CNV, LTC4282_CLKOUT_SYSTEM
178};
179
180static long ltc4282_round_rate(struct clk_hw *hw, unsigned long rate,
181 unsigned long *parent_rate)
182{
183 int idx = find_closest(rate, ltc4282_out_rates,
184 ARRAY_SIZE(ltc4282_out_rates));
185
186 return ltc4282_out_rates[idx];
187}
188
189static unsigned long ltc4282_recalc_rate(struct clk_hw *hw,
190 unsigned long parent)
191{
192 struct ltc4282_state *st = container_of(hw, struct ltc4282_state,
193 clk_hw);
194 u32 clkdiv;
195 int ret;
196
197 ret = regmap_read(st->map, LTC4282_CLK_DIV, &clkdiv);
198 if (ret)
199 return 0;
200
201 clkdiv = FIELD_GET(LTC4282_CLKOUT_MASK, clkdiv);
202 if (!clkdiv)
203 return 0;
204 if (clkdiv == LTC4282_CLKOUT_INT)
205 return LTC4282_CLKOUT_SYSTEM;
206
207 return LTC4282_CLKOUT_CNV;
208}
209
210static void ltc4282_disable(struct clk_hw *clk_hw)
211{
212 struct ltc4282_state *st = container_of(clk_hw, struct ltc4282_state,
213 clk_hw);
214
215 regmap_clear_bits(st->map, LTC4282_CLK_DIV, LTC4282_CLKOUT_MASK);
216}
217
218static int ltc4282_read_voltage_word(const struct ltc4282_state *st, u32 reg,
219 u32 fs, long *val)
220{
221 __be16 in;
222 int ret;
223
224 ret = regmap_bulk_read(st->map, reg, &in, sizeof(in));
225 if (ret)
226 return ret;
227
228 /*
229 * This is also used to calculate current in which case fs comes in
230 * 10 * uV. Hence the ULL usage.
231 */
232 *val = DIV_ROUND_CLOSEST_ULL(be16_to_cpu(in) * (u64)fs, U16_MAX);
233 return 0;
234}
235
236static int ltc4282_read_voltage_byte_cached(const struct ltc4282_state *st,
237 u32 reg, u32 fs, long *val,
238 u32 *cached_raw)
239{
240 int ret;
241 u32 in;
242
243 if (cached_raw) {
244 in = *cached_raw;
245 } else {
246 ret = regmap_read(st->map, reg, &in);
247 if (ret)
248 return ret;
249 }
250
251 *val = DIV_ROUND_CLOSEST(in * fs, U8_MAX);
252 return 0;
253}
254
255static int ltc4282_read_voltage_byte(const struct ltc4282_state *st, u32 reg,
256 u32 fs, long *val)
257{
258 return ltc4282_read_voltage_byte_cached(st, reg, fs, val, NULL);
259}
260
261static int __ltc4282_read_alarm(struct ltc4282_state *st, u32 reg, u32 mask,
262 long *val)
263{
264 u32 alarm;
265 int ret;
266
267 ret = regmap_read(st->map, reg, &alarm);
268 if (ret)
269 return ret;
270
271 *val = !!(alarm & mask);
272
273 /* if not status/fault logs, clear the alarm after reading it */
274 if (reg != LTC4282_STATUS_LSB && reg != LTC4282_FAULT_LOG)
275 return regmap_clear_bits(st->map, reg, mask);
276
277 return 0;
278}
279
280static int ltc4282_read_alarm(struct ltc4282_state *st, u32 reg, u32 mask,
281 long *val)
282{
283 guard(mutex)(&st->lock);
284 return __ltc4282_read_alarm(st, reg, mask, val);
285}
286
287static int ltc4282_vdd_source_read_in(struct ltc4282_state *st, u32 channel,
288 long *val)
289{
290 guard(mutex)(&st->lock);
291 if (!st->in0_1_cache[channel].en)
292 return -ENODATA;
293
294 return ltc4282_read_voltage_word(st, LTC4282_VSOURCE, st->vfs_out, val);
295}
296
297static int ltc4282_vdd_source_read_hist(struct ltc4282_state *st, u32 reg,
298 u32 channel, long *cached, long *val)
299{
300 int ret;
301
302 guard(mutex)(&st->lock);
303 if (!st->in0_1_cache[channel].en) {
304 *val = *cached;
305 return 0;
306 }
307
308 ret = ltc4282_read_voltage_word(st, reg, st->vfs_out, val);
309 if (ret)
310 return ret;
311
312 *cached = *val;
313 return 0;
314}
315
316static int ltc4282_vdd_source_read_lim(struct ltc4282_state *st, u32 reg,
317 u32 channel, u32 *cached, long *val)
318{
319 guard(mutex)(&st->lock);
320 if (!st->in0_1_cache[channel].en)
321 return ltc4282_read_voltage_byte_cached(st, reg, st->vfs_out,
322 val, cached);
323
324 return ltc4282_read_voltage_byte(st, reg, st->vfs_out, val);
325}
326
327static int ltc4282_vdd_source_read_alm(struct ltc4282_state *st, u32 mask,
328 u32 channel, long *val)
329{
330 guard(mutex)(&st->lock);
331 if (!st->in0_1_cache[channel].en) {
332 /*
333 * Do this otherwise alarms can get confused because we clear
334 * them after reading them. So, if someone mistakenly reads
335 * VSOURCE right before VDD (or the other way around), we might
336 * get no alarm just because it was cleared when reading VSOURCE
337 * and had no time for a new conversion and thus having the
338 * alarm again.
339 */
340 *val = 0;
341 return 0;
342 }
343
344 return __ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG, mask, val);
345}
346
347static int ltc4282_read_in(struct ltc4282_state *st, u32 attr, long *val,
348 u32 channel)
349{
350 switch (attr) {
351 case hwmon_in_input:
352 if (channel == LTC4282_CHAN_VGPIO)
353 return ltc4282_read_voltage_word(st, LTC4282_VGPIO,
354 1280, val);
355
356 return ltc4282_vdd_source_read_in(st, channel, val);
357 case hwmon_in_highest:
358 if (channel == LTC4282_CHAN_VGPIO)
359 return ltc4282_read_voltage_word(st,
360 LTC4282_VGPIO_HIGHEST,
361 1280, val);
362
363 return ltc4282_vdd_source_read_hist(st, LTC4282_VSOURCE_HIGHEST,
364 channel,
365 &st->in0_1_cache[channel].in_highest, val);
366 case hwmon_in_lowest:
367 if (channel == LTC4282_CHAN_VGPIO)
368 return ltc4282_read_voltage_word(st, LTC4282_VGPIO_LOWEST,
369 1280, val);
370
371 return ltc4282_vdd_source_read_hist(st, LTC4282_VSOURCE_LOWEST,
372 channel,
373 &st->in0_1_cache[channel].in_lowest, val);
374 case hwmon_in_max_alarm:
375 if (channel == LTC4282_CHAN_VGPIO)
376 return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
377 LTC4282_GPIO_ALARM_H_MASK,
378 val);
379
380 return ltc4282_vdd_source_read_alm(st,
381 LTC4282_VSOURCE_ALARM_H_MASK,
382 channel, val);
383 case hwmon_in_min_alarm:
384 if (channel == LTC4282_CHAN_VGPIO)
385 ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
386 LTC4282_GPIO_ALARM_L_MASK, val);
387
388 return ltc4282_vdd_source_read_alm(st,
389 LTC4282_VSOURCE_ALARM_L_MASK,
390 channel, val);
391 case hwmon_in_crit_alarm:
392 return ltc4282_read_alarm(st, LTC4282_STATUS_LSB,
393 LTC4282_OV_STATUS_MASK, val);
394 case hwmon_in_lcrit_alarm:
395 return ltc4282_read_alarm(st, LTC4282_STATUS_LSB,
396 LTC4282_UV_STATUS_MASK, val);
397 case hwmon_in_max:
398 if (channel == LTC4282_CHAN_VGPIO)
399 return ltc4282_read_voltage_byte(st, LTC4282_VGPIO_MAX,
400 1280, val);
401
402 return ltc4282_vdd_source_read_lim(st, LTC4282_VSOURCE_MAX,
403 channel,
404 &st->in0_1_cache[channel].in_max_raw, val);
405 case hwmon_in_min:
406 if (channel == LTC4282_CHAN_VGPIO)
407 return ltc4282_read_voltage_byte(st, LTC4282_VGPIO_MIN,
408 1280, val);
409
410 return ltc4282_vdd_source_read_lim(st, LTC4282_VSOURCE_MIN,
411 channel,
412 &st->in0_1_cache[channel].in_min_raw, val);
413 case hwmon_in_enable:
414 scoped_guard(mutex, &st->lock) {
415 *val = st->in0_1_cache[channel].en;
416 }
417 return 0;
418 case hwmon_in_fault:
419 /*
420 * We report failure if we detect either a fer_bad or a
421 * fet_short in the status register.
422 */
423 return ltc4282_read_alarm(st, LTC4282_STATUS_LSB,
424 LTC4282_FET_FAILURE_MASK, val);
425 default:
426 return -EOPNOTSUPP;
427 }
428}
429
430static int ltc4282_read_current_word(const struct ltc4282_state *st, u32 reg,
431 long *val)
432{
433 long in;
434 int ret;
435
436 /*
437 * We pass in full scale in 10 * micro (note that 40 is already
438 * millivolt) so we have better approximations to calculate current.
439 */
440 ret = ltc4282_read_voltage_word(st, reg, DECA * 40 * MILLI, &in);
441 if (ret)
442 return ret;
443
444 *val = DIV_ROUND_CLOSEST(in * MILLI, st->rsense);
445
446 return 0;
447}
448
449static int ltc4282_read_current_byte(const struct ltc4282_state *st, u32 reg,
450 long *val)
451{
452 long in;
453 int ret;
454
455 ret = ltc4282_read_voltage_byte(st, reg, DECA * 40 * MILLI, &in);
456 if (ret)
457 return ret;
458
459 *val = DIV_ROUND_CLOSEST(in * MILLI, st->rsense);
460
461 return 0;
462}
463
464static int ltc4282_read_curr(struct ltc4282_state *st, const u32 attr,
465 long *val)
466{
467 switch (attr) {
468 case hwmon_curr_input:
469 return ltc4282_read_current_word(st, LTC4282_VSENSE, val);
470 case hwmon_curr_highest:
471 return ltc4282_read_current_word(st, LTC4282_VSENSE_HIGHEST,
472 val);
473 case hwmon_curr_lowest:
474 return ltc4282_read_current_word(st, LTC4282_VSENSE_LOWEST,
475 val);
476 case hwmon_curr_max:
477 return ltc4282_read_current_byte(st, LTC4282_VSENSE_MAX, val);
478 case hwmon_curr_min:
479 return ltc4282_read_current_byte(st, LTC4282_VSENSE_MIN, val);
480 case hwmon_curr_max_alarm:
481 return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
482 LTC4282_VSENSE_ALARM_H_MASK, val);
483 case hwmon_curr_min_alarm:
484 return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
485 LTC4282_VSENSE_ALARM_L_MASK, val);
486 case hwmon_curr_crit_alarm:
487 return ltc4282_read_alarm(st, LTC4282_STATUS_LSB,
488 LTC4282_OC_STATUS_MASK, val);
489 default:
490 return -EOPNOTSUPP;
491 }
492}
493
494static int ltc4282_read_power_word(const struct ltc4282_state *st, u32 reg,
495 long *val)
496{
497 u64 temp = DECA * 40ULL * st->vfs_out * BIT(16), temp_2;
498 __be16 raw;
499 u16 power;
500 int ret;
501
502 ret = regmap_bulk_read(st->map, reg, &raw, sizeof(raw));
503 if (ret)
504 return ret;
505
506 power = be16_to_cpu(raw);
507 /*
508 * Power is given by:
509 * P = CODE(16b) * 0.040 * Vfs(out) * 2^16 / ((2^16 - 1)^2 * Rsense)
510 */
511 if (check_mul_overflow(power * temp, MICRO, &temp_2)) {
512 temp = DIV_ROUND_CLOSEST_ULL(power * temp, U16_MAX);
513 *val = DIV64_U64_ROUND_CLOSEST(temp * MICRO,
514 U16_MAX * (u64)st->rsense);
515 return 0;
516 }
517
518 *val = DIV64_U64_ROUND_CLOSEST(temp_2,
519 st->rsense * int_pow(U16_MAX, 2));
520
521 return 0;
522}
523
524static int ltc4282_read_power_byte(const struct ltc4282_state *st, u32 reg,
525 long *val)
526{
527 u32 power;
528 u64 temp;
529 int ret;
530
531 ret = regmap_read(st->map, reg, &power);
532 if (ret)
533 return ret;
534
535 temp = power * 40 * DECA * st->vfs_out * BIT_ULL(8);
536 *val = DIV64_U64_ROUND_CLOSEST(temp * MICRO,
537 int_pow(U8_MAX, 2) * st->rsense);
538
539 return 0;
540}
541
542static int ltc4282_read_energy(const struct ltc4282_state *st, u64 *val)
543{
544 u64 temp, energy;
545 __be64 raw;
546 int ret;
547
548 ret = regmap_bulk_read(st->map, LTC4282_ENERGY, &raw, 6);
549 if (ret)
550 return ret;
551
552 energy = be64_to_cpu(raw) >> 16;
553 /*
554 * The formula for energy is given by:
555 * E = CODE(48b) * 0.040 * Vfs(out) * Tconv * 256 /
556 * ((2^16 - 1)^2 * Rsense)
557 *
558 * Since we only support 12bit ADC, Tconv = 0.065535s. Passing Vfs(out)
559 * and 0.040 to mV and Tconv to us, we can simplify the formula to:
560 * E = CODE(48b) * 40 * Vfs(out) * 256 / (U16_MAX * Rsense)
561 *
562 * As Rsense can have tenths of micro-ohm resolution, we need to
563 * multiply by DECA to get microujoule.
564 */
565 if (check_mul_overflow(DECA * st->vfs_out * 40 * BIT(8), energy, &temp)) {
566 temp = DIV_ROUND_CLOSEST(DECA * st->vfs_out * 40 * BIT(8), U16_MAX);
567 *val = DIV_ROUND_CLOSEST_ULL(temp * energy, st->rsense);
568 return 0;
569 }
570
571 *val = DIV64_U64_ROUND_CLOSEST(temp, U16_MAX * (u64)st->rsense);
572
573 return 0;
574}
575
576static int ltc4282_read_power(struct ltc4282_state *st, const u32 attr,
577 long *val)
578{
579 switch (attr) {
580 case hwmon_power_input:
581 return ltc4282_read_power_word(st, LTC4282_POWER, val);
582 case hwmon_power_input_highest:
583 return ltc4282_read_power_word(st, LTC4282_POWER_HIGHEST, val);
584 case hwmon_power_input_lowest:
585 return ltc4282_read_power_word(st, LTC4282_POWER_LOWEST, val);
586 case hwmon_power_max_alarm:
587 return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
588 LTC4282_POWER_ALARM_H_MASK, val);
589 case hwmon_power_min_alarm:
590 return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
591 LTC4282_POWER_ALARM_L_MASK, val);
592 case hwmon_power_max:
593 return ltc4282_read_power_byte(st, LTC4282_POWER_MAX, val);
594 case hwmon_power_min:
595 return ltc4282_read_power_byte(st, LTC4282_POWER_MIN, val);
596 default:
597 return -EOPNOTSUPP;
598 }
599}
600
601static int ltc4282_read(struct device *dev, enum hwmon_sensor_types type,
602 u32 attr, int channel, long *val)
603{
604 struct ltc4282_state *st = dev_get_drvdata(dev);
605
606 switch (type) {
607 case hwmon_in:
608 return ltc4282_read_in(st, attr, val, channel);
609 case hwmon_curr:
610 return ltc4282_read_curr(st, attr, val);
611 case hwmon_power:
612 return ltc4282_read_power(st, attr, val);
613 case hwmon_energy:
614 scoped_guard(mutex, &st->lock) {
615 *val = st->energy_en;
616 }
617 return 0;
618 default:
619 return -EOPNOTSUPP;
620 }
621}
622
623static int ltc4282_write_power_byte(const struct ltc4282_state *st, u32 reg,
624 long val)
625{
626 u32 power;
627 u64 temp;
628
629 if (val > st->power_max)
630 val = st->power_max;
631
632 temp = val * int_pow(U8_MAX, 2) * st->rsense;
633 power = DIV64_U64_ROUND_CLOSEST(temp,
634 MICRO * DECA * 256ULL * st->vfs_out * 40);
635
636 return regmap_write(st->map, reg, power);
637}
638
639static int ltc4282_write_power_word(const struct ltc4282_state *st, u32 reg,
640 long val)
641{
642 u64 temp = int_pow(U16_MAX, 2) * st->rsense, temp_2;
643 __be16 __raw;
644 u16 code;
645
646 if (check_mul_overflow(temp, val, &temp_2)) {
647 temp = DIV_ROUND_CLOSEST_ULL(temp, DECA * MICRO);
648 code = DIV64_U64_ROUND_CLOSEST(temp * val,
649 40ULL * BIT(16) * st->vfs_out);
650 } else {
651 temp = DECA * MICRO * 40ULL * BIT(16) * st->vfs_out;
652 code = DIV64_U64_ROUND_CLOSEST(temp_2, temp);
653 }
654
655 __raw = cpu_to_be16(code);
656 return regmap_bulk_write(st->map, reg, &__raw, sizeof(__raw));
657}
658
659static int __ltc4282_in_write_history(const struct ltc4282_state *st, u32 reg,
660 long lowest, long highest, u32 fs)
661{
662 __be16 __raw;
663 u16 tmp;
664 int ret;
665
666 tmp = DIV_ROUND_CLOSEST(U16_MAX * lowest, fs);
667
668 __raw = cpu_to_be16(tmp);
669
670 ret = regmap_bulk_write(st->map, reg, &__raw, 2);
671 if (ret)
672 return ret;
673
674 tmp = DIV_ROUND_CLOSEST(U16_MAX * highest, fs);
675
676 __raw = cpu_to_be16(tmp);
677
678 return regmap_bulk_write(st->map, reg + 2, &__raw, 2);
679}
680
681static int ltc4282_in_write_history(struct ltc4282_state *st, u32 reg,
682 long lowest, long highest, u32 fs)
683{
684 guard(mutex)(&st->lock);
685 return __ltc4282_in_write_history(st, reg, lowest, highest, fs);
686}
687
688static int ltc4282_power_reset_hist(struct ltc4282_state *st)
689{
690 int ret;
691
692 guard(mutex)(&st->lock);
693
694 ret = ltc4282_write_power_word(st, LTC4282_POWER_LOWEST,
695 st->power_max);
696 if (ret)
697 return ret;
698
699 ret = ltc4282_write_power_word(st, LTC4282_POWER_HIGHEST, 0);
700 if (ret)
701 return ret;
702
703 /* now, let's also clear possible power_bad fault logs */
704 return regmap_clear_bits(st->map, LTC4282_FAULT_LOG,
705 LTC4282_POWER_BAD_FAULT_MASK);
706}
707
708static int ltc4282_write_power(struct ltc4282_state *st, u32 attr,
709 long val)
710{
711 switch (attr) {
712 case hwmon_power_max:
713 return ltc4282_write_power_byte(st, LTC4282_POWER_MAX, val);
714 case hwmon_power_min:
715 return ltc4282_write_power_byte(st, LTC4282_POWER_MIN, val);
716 case hwmon_power_reset_history:
717 return ltc4282_power_reset_hist(st);
718 default:
719 return -EOPNOTSUPP;
720 }
721}
722
723static int ltc4282_write_voltage_byte_cached(const struct ltc4282_state *st,
724 u32 reg, u32 fs, long val,
725 u32 *cache_raw)
726{
727 u32 in;
728
729 val = clamp_val(val, 0, fs);
730 in = DIV_ROUND_CLOSEST(val * U8_MAX, fs);
731
732 if (cache_raw) {
733 *cache_raw = in;
734 return 0;
735 }
736
737 return regmap_write(st->map, reg, in);
738}
739
740static int ltc4282_write_voltage_byte(const struct ltc4282_state *st, u32 reg,
741 u32 fs, long val)
742{
743 return ltc4282_write_voltage_byte_cached(st, reg, fs, val, NULL);
744}
745
746static int ltc4282_cache_history(struct ltc4282_state *st, u32 channel)
747{
748 long val;
749 int ret;
750
751 ret = ltc4282_read_voltage_word(st, LTC4282_VSOURCE_LOWEST, st->vfs_out,
752 &val);
753 if (ret)
754 return ret;
755
756 st->in0_1_cache[channel].in_lowest = val;
757
758 ret = ltc4282_read_voltage_word(st, LTC4282_VSOURCE_HIGHEST,
759 st->vfs_out, &val);
760 if (ret)
761 return ret;
762
763 st->in0_1_cache[channel].in_highest = val;
764
765 ret = regmap_read(st->map, LTC4282_VSOURCE_MIN,
766 &st->in0_1_cache[channel].in_min_raw);
767 if (ret)
768 return ret;
769
770 return regmap_read(st->map, LTC4282_VSOURCE_MAX,
771 &st->in0_1_cache[channel].in_max_raw);
772}
773
774static int ltc4282_cache_sync(struct ltc4282_state *st, u32 channel)
775{
776 int ret;
777
778 ret = __ltc4282_in_write_history(st, LTC4282_VSOURCE_LOWEST,
779 st->in0_1_cache[channel].in_lowest,
780 st->in0_1_cache[channel].in_highest,
781 st->vfs_out);
782 if (ret)
783 return ret;
784
785 ret = regmap_write(st->map, LTC4282_VSOURCE_MIN,
786 st->in0_1_cache[channel].in_min_raw);
787 if (ret)
788 return ret;
789
790 return regmap_write(st->map, LTC4282_VSOURCE_MAX,
791 st->in0_1_cache[channel].in_max_raw);
792}
793
794static int ltc4282_vdd_source_write_lim(struct ltc4282_state *st, u32 reg,
795 int channel, u32 *cache, long val)
796{
797 int ret;
798
799 guard(mutex)(&st->lock);
800 if (st->in0_1_cache[channel].en)
801 ret = ltc4282_write_voltage_byte(st, reg, st->vfs_out, val);
802 else
803 ret = ltc4282_write_voltage_byte_cached(st, reg, st->vfs_out,
804 val, cache);
805
806 return ret;
807}
808
809static int ltc4282_vdd_source_reset_hist(struct ltc4282_state *st, int channel)
810{
811 long lowest = st->vfs_out;
812 int ret;
813
814 if (channel == LTC4282_CHAN_VDD)
815 lowest = st->vdd;
816
817 guard(mutex)(&st->lock);
818 if (st->in0_1_cache[channel].en) {
819 ret = __ltc4282_in_write_history(st, LTC4282_VSOURCE_LOWEST,
820 lowest, 0, st->vfs_out);
821 if (ret)
822 return ret;
823 }
824
825 st->in0_1_cache[channel].in_lowest = lowest;
826 st->in0_1_cache[channel].in_highest = 0;
827
828 /*
829 * We are also clearing possible fault logs in reset_history. Clearing
830 * the logs might be important when the auto retry bits are not enabled
831 * as the chip only enables the output again after having these logs
832 * cleared. As some of these logs are related to limits, it makes sense
833 * to clear them in here. For VDD, we need to clear under/over voltage
834 * events. For VSOURCE, fet_short and fet_bad...
835 */
836 if (channel == LTC4282_CHAN_VSOURCE)
837 return regmap_clear_bits(st->map, LTC4282_FAULT_LOG,
838 LTC4282_FET_FAILURE_FAULT_MASK);
839
840 return regmap_clear_bits(st->map, LTC4282_FAULT_LOG,
841 LTC4282_VDD_FAULT_MASK);
842}
843
844/*
845 * We need to mux between VSOURCE and VDD which means they are mutually
846 * exclusive. Moreover, we can't really disable both VDD and VSOURCE as the ADC
847 * is continuously running (we cannot independently halt it without also
848 * stopping VGPIO). Hence, the logic is that disabling or enabling VDD will
849 * automatically have the reverse effect on VSOURCE and vice-versa.
850 */
851static int ltc4282_vdd_source_enable(struct ltc4282_state *st, int channel,
852 long val)
853{
854 int ret, other_chan = ~channel & 0x1;
855 u8 __val = val;
856
857 guard(mutex)(&st->lock);
858 if (st->in0_1_cache[channel].en == !!val)
859 return 0;
860
861 /* clearing the bit makes the ADC to monitor VDD */
862 if (channel == LTC4282_CHAN_VDD)
863 __val = !__val;
864
865 ret = regmap_update_bits(st->map, LTC4282_ILIM_ADJUST,
866 LTC4282_VDD_MONITOR_MASK,
867 FIELD_PREP(LTC4282_VDD_MONITOR_MASK, !!__val));
868 if (ret)
869 return ret;
870
871 st->in0_1_cache[channel].en = !!val;
872 st->in0_1_cache[other_chan].en = !val;
873
874 if (st->in0_1_cache[channel].en) {
875 /*
876 * Then, we are disabling @other_chan. Let's save it's current
877 * history.
878 */
879 ret = ltc4282_cache_history(st, other_chan);
880 if (ret)
881 return ret;
882
883 return ltc4282_cache_sync(st, channel);
884 }
885 /*
886 * Then, we are enabling @other_chan. We need to do the opposite from
887 * above.
888 */
889 ret = ltc4282_cache_history(st, channel);
890 if (ret)
891 return ret;
892
893 return ltc4282_cache_sync(st, other_chan);
894}
895
896static int ltc4282_write_in(struct ltc4282_state *st, u32 attr, long val,
897 int channel)
898{
899 switch (attr) {
900 case hwmon_in_max:
901 if (channel == LTC4282_CHAN_VGPIO)
902 return ltc4282_write_voltage_byte(st, LTC4282_VGPIO_MAX,
903 1280, val);
904
905 return ltc4282_vdd_source_write_lim(st, LTC4282_VSOURCE_MAX,
906 channel,
907 &st->in0_1_cache[channel].in_max_raw, val);
908 case hwmon_in_min:
909 if (channel == LTC4282_CHAN_VGPIO)
910 return ltc4282_write_voltage_byte(st, LTC4282_VGPIO_MIN,
911 1280, val);
912
913 return ltc4282_vdd_source_write_lim(st, LTC4282_VSOURCE_MIN,
914 channel,
915 &st->in0_1_cache[channel].in_min_raw, val);
916 case hwmon_in_reset_history:
917 if (channel == LTC4282_CHAN_VGPIO)
918 return ltc4282_in_write_history(st,
919 LTC4282_VGPIO_LOWEST,
920 1280, 0, 1280);
921
922 return ltc4282_vdd_source_reset_hist(st, channel);
923 case hwmon_in_enable:
924 return ltc4282_vdd_source_enable(st, channel, val);
925 default:
926 return -EOPNOTSUPP;
927 }
928}
929
930static int ltc4282_curr_reset_hist(struct ltc4282_state *st)
931{
932 int ret;
933
934 guard(mutex)(&st->lock);
935
936 ret = __ltc4282_in_write_history(st, LTC4282_VSENSE_LOWEST,
937 st->vsense_max, 0, 40 * MILLI);
938 if (ret)
939 return ret;
940
941 /* now, let's also clear possible overcurrent fault logs */
942 return regmap_clear_bits(st->map, LTC4282_FAULT_LOG,
943 LTC4282_OC_FAULT_MASK);
944}
945
946static int ltc4282_write_curr(struct ltc4282_state *st, u32 attr,
947 long val)
948{
949 /* need to pass it in millivolt */
950 u32 in = DIV_ROUND_CLOSEST_ULL((u64)val * st->rsense, DECA * MICRO);
951
952 switch (attr) {
953 case hwmon_curr_max:
954 return ltc4282_write_voltage_byte(st, LTC4282_VSENSE_MAX, 40,
955 in);
956 case hwmon_curr_min:
957 return ltc4282_write_voltage_byte(st, LTC4282_VSENSE_MIN, 40,
958 in);
959 case hwmon_curr_reset_history:
960 return ltc4282_curr_reset_hist(st);
961 default:
962 return -EOPNOTSUPP;
963 }
964}
965
966static int ltc4282_energy_enable_set(struct ltc4282_state *st, long val)
967{
968 int ret;
969
970 guard(mutex)(&st->lock);
971 /* setting the bit halts the meter */
972 ret = regmap_update_bits(st->map, LTC4282_ADC_CTRL,
973 LTC4282_METER_HALT_MASK,
974 FIELD_PREP(LTC4282_METER_HALT_MASK, !val));
975 if (ret)
976 return ret;
977
978 st->energy_en = !!val;
979
980 return 0;
981}
982
983static int ltc4282_write(struct device *dev,
984 enum hwmon_sensor_types type,
985 u32 attr, int channel, long val)
986{
987 struct ltc4282_state *st = dev_get_drvdata(dev);
988
989 switch (type) {
990 case hwmon_power:
991 return ltc4282_write_power(st, attr, val);
992 case hwmon_in:
993 return ltc4282_write_in(st, attr, val, channel);
994 case hwmon_curr:
995 return ltc4282_write_curr(st, attr, val);
996 case hwmon_energy:
997 return ltc4282_energy_enable_set(st, val);
998 default:
999 return -EOPNOTSUPP;
1000 }
1001}
1002
1003static umode_t ltc4282_in_is_visible(const struct ltc4282_state *st, u32 attr)
1004{
1005 switch (attr) {
1006 case hwmon_in_input:
1007 case hwmon_in_highest:
1008 case hwmon_in_lowest:
1009 case hwmon_in_max_alarm:
1010 case hwmon_in_min_alarm:
1011 case hwmon_in_label:
1012 case hwmon_in_lcrit_alarm:
1013 case hwmon_in_crit_alarm:
1014 case hwmon_in_fault:
1015 return 0444;
1016 case hwmon_in_max:
1017 case hwmon_in_min:
1018 case hwmon_in_enable:
1019 case hwmon_in_reset_history:
1020 return 0644;
1021 default:
1022 return 0;
1023 }
1024}
1025
1026static umode_t ltc4282_curr_is_visible(u32 attr)
1027{
1028 switch (attr) {
1029 case hwmon_curr_input:
1030 case hwmon_curr_highest:
1031 case hwmon_curr_lowest:
1032 case hwmon_curr_max_alarm:
1033 case hwmon_curr_min_alarm:
1034 case hwmon_curr_crit_alarm:
1035 case hwmon_curr_label:
1036 return 0444;
1037 case hwmon_curr_max:
1038 case hwmon_curr_min:
1039 case hwmon_curr_reset_history:
1040 return 0644;
1041 default:
1042 return 0;
1043 }
1044}
1045
1046static umode_t ltc4282_power_is_visible(u32 attr)
1047{
1048 switch (attr) {
1049 case hwmon_power_input:
1050 case hwmon_power_input_highest:
1051 case hwmon_power_input_lowest:
1052 case hwmon_power_label:
1053 case hwmon_power_max_alarm:
1054 case hwmon_power_min_alarm:
1055 return 0444;
1056 case hwmon_power_max:
1057 case hwmon_power_min:
1058 case hwmon_power_reset_history:
1059 return 0644;
1060 default:
1061 return 0;
1062 }
1063}
1064
1065static umode_t ltc4282_is_visible(const void *data,
1066 enum hwmon_sensor_types type,
1067 u32 attr, int channel)
1068{
1069 switch (type) {
1070 case hwmon_in:
1071 return ltc4282_in_is_visible(data, attr);
1072 case hwmon_curr:
1073 return ltc4282_curr_is_visible(attr);
1074 case hwmon_power:
1075 return ltc4282_power_is_visible(attr);
1076 case hwmon_energy:
1077 /* hwmon_energy_enable */
1078 return 0644;
1079 default:
1080 return 0;
1081 }
1082}
1083
1084static const char * const ltc4282_in_strs[] = {
1085 "VSOURCE", "VDD", "VGPIO"
1086};
1087
1088static int ltc4282_read_labels(struct device *dev,
1089 enum hwmon_sensor_types type,
1090 u32 attr, int channel, const char **str)
1091{
1092 switch (type) {
1093 case hwmon_in:
1094 *str = ltc4282_in_strs[channel];
1095 return 0;
1096 case hwmon_curr:
1097 *str = "ISENSE";
1098 return 0;
1099 case hwmon_power:
1100 *str = "Power";
1101 return 0;
1102 default:
1103 return -EOPNOTSUPP;
1104 }
1105}
1106
1107static ssize_t ltc4282_energy_show(struct device *dev,
1108 struct device_attribute *da, char *buf)
1109{
1110 struct ltc4282_state *st = dev_get_drvdata(dev);
1111 u64 energy;
1112 int ret;
1113
1114 guard(mutex)(&st->lock);
1115 if (!st->energy_en)
1116 return -ENODATA;
1117
1118 ret = ltc4282_read_energy(st, &energy);
1119 if (ret < 0)
1120 return ret;
1121
1122 return sysfs_emit(buf, "%llu\n", energy);
1123}
1124
1125static const struct clk_ops ltc4282_ops = {
1126 .recalc_rate = ltc4282_recalc_rate,
1127 .round_rate = ltc4282_round_rate,
1128 .set_rate = ltc4282_set_rate,
1129 .disable = ltc4282_disable,
1130};
1131
1132static int ltc428_clk_provider_setup(struct ltc4282_state *st,
1133 struct device *dev)
1134{
1135 struct clk_init_data init;
1136 int ret;
1137
1138 if (!IS_ENABLED(CONFIG_COMMON_CLK))
1139 return 0;
1140
1141 init.name = devm_kasprintf(dev, GFP_KERNEL, "%s-clk",
1142 fwnode_get_name(dev_fwnode(dev)));
1143 if (!init.name)
1144 return -ENOMEM;
1145
1146 init.ops = <c4282_ops;
1147 init.flags = CLK_GET_RATE_NOCACHE;
1148 st->clk_hw.init = &init;
1149
1150 ret = devm_clk_hw_register(dev, &st->clk_hw);
1151 if (ret)
1152 return ret;
1153
1154 return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
1155 &st->clk_hw);
1156}
1157
1158static int ltc428_clks_setup(struct ltc4282_state *st, struct device *dev)
1159{
1160 unsigned long rate;
1161 struct clk *clkin;
1162 u32 val;
1163 int ret;
1164
1165 ret = ltc428_clk_provider_setup(st, dev);
1166 if (ret)
1167 return ret;
1168
1169 clkin = devm_clk_get_optional_enabled(dev, NULL);
1170 if (IS_ERR(clkin))
1171 return dev_err_probe(dev, PTR_ERR(clkin),
1172 "Failed to get clkin");
1173 if (!clkin)
1174 return 0;
1175
1176 rate = clk_get_rate(clkin);
1177 if (!in_range(rate, LTC4282_CLKIN_MIN, LTC4282_CLKIN_RANGE))
1178 return dev_err_probe(dev, -EINVAL,
1179 "Invalid clkin range(%lu) [%lu %lu]\n",
1180 rate, LTC4282_CLKIN_MIN,
1181 LTC4282_CLKIN_MAX);
1182
1183 /*
1184 * Clocks faster than 250KHZ should be reduced to 250KHZ. The clock
1185 * frequency is divided by twice the value in the register.
1186 */
1187 val = rate / (2 * LTC4282_CLKIN_MIN);
1188
1189 return regmap_update_bits(st->map, LTC4282_CLK_DIV,
1190 LTC4282_CLK_DIV_MASK,
1191 FIELD_PREP(LTC4282_CLK_DIV_MASK, val));
1192}
1193
1194static const int ltc4282_curr_lim_uv[] = {
1195 12500, 15625, 18750, 21875, 25000, 28125, 31250, 34375
1196};
1197
1198static int ltc4282_get_defaults(struct ltc4282_state *st, u32 *vin_mode)
1199{
1200 u32 reg_val, ilm_adjust;
1201 int ret;
1202
1203 ret = regmap_read(st->map, LTC4282_ADC_CTRL, ®_val);
1204 if (ret)
1205 return ret;
1206
1207 st->energy_en = !FIELD_GET(LTC4282_METER_HALT_MASK, reg_val);
1208
1209 ret = regmap_read(st->map, LTC4282_CTRL_MSB, ®_val);
1210 if (ret)
1211 return ret;
1212
1213 *vin_mode = FIELD_GET(LTC4282_CTRL_VIN_MODE_MASK, reg_val);
1214
1215 ret = regmap_read(st->map, LTC4282_ILIM_ADJUST, ®_val);
1216 if (ret)
1217 return ret;
1218
1219 ilm_adjust = FIELD_GET(LTC4282_ILIM_ADJUST_MASK, reg_val);
1220 st->vsense_max = ltc4282_curr_lim_uv[ilm_adjust];
1221
1222 st->in0_1_cache[LTC4282_CHAN_VSOURCE].en = FIELD_GET(LTC4282_VDD_MONITOR_MASK,
1223 ilm_adjust);
1224 if (!st->in0_1_cache[LTC4282_CHAN_VSOURCE].en) {
1225 st->in0_1_cache[LTC4282_CHAN_VDD].en = true;
1226 return regmap_read(st->map, LTC4282_VSOURCE_MAX,
1227 &st->in0_1_cache[LTC4282_CHAN_VSOURCE].in_max_raw);
1228 }
1229
1230 return regmap_read(st->map, LTC4282_VSOURCE_MAX,
1231 &st->in0_1_cache[LTC4282_CHAN_VDD].in_max_raw);
1232}
1233
1234/*
1235 * Set max limits for ISENSE and Power as that depends on the max voltage on
1236 * rsense that is defined in ILIM_ADJUST. This is specially important for power
1237 * because for some rsense and vfsout values, if we allow the default raw 255
1238 * value, that would overflow long in 32bit archs when reading back the max
1239 * power limit.
1240 *
1241 * Also set meaningful historic values for VDD and VSOURCE
1242 * (0 would not mean much).
1243 */
1244static int ltc4282_set_max_limits(struct ltc4282_state *st)
1245{
1246 int ret;
1247
1248 ret = ltc4282_write_voltage_byte(st, LTC4282_VSENSE_MAX, 40 * MILLI,
1249 st->vsense_max);
1250 if (ret)
1251 return ret;
1252
1253 /* Power is given by ISENSE * Vout. */
1254 st->power_max = DIV_ROUND_CLOSEST(st->vsense_max * DECA * MILLI, st->rsense) * st->vfs_out;
1255 ret = ltc4282_write_power_byte(st, LTC4282_POWER_MAX, st->power_max);
1256 if (ret)
1257 return ret;
1258
1259 if (st->in0_1_cache[LTC4282_CHAN_VDD].en) {
1260 st->in0_1_cache[LTC4282_CHAN_VSOURCE].in_lowest = st->vfs_out;
1261 return __ltc4282_in_write_history(st, LTC4282_VSOURCE_LOWEST,
1262 st->vdd, 0, st->vfs_out);
1263 }
1264
1265 st->in0_1_cache[LTC4282_CHAN_VDD].in_lowest = st->vdd;
1266 return __ltc4282_in_write_history(st, LTC4282_VSOURCE_LOWEST,
1267 st->vfs_out, 0, st->vfs_out);
1268}
1269
1270static const char * const ltc4282_gpio1_modes[] = {
1271 "power_bad", "power_good"
1272};
1273
1274static const char * const ltc4282_gpio2_modes[] = {
1275 "adc_input", "stress_fet"
1276};
1277
1278static int ltc4282_gpio_setup(struct ltc4282_state *st, struct device *dev)
1279{
1280 const char *func = NULL;
1281 int ret;
1282
1283 ret = device_property_read_string(dev, "adi,gpio1-mode", &func);
1284 if (!ret) {
1285 ret = match_string(ltc4282_gpio1_modes,
1286 ARRAY_SIZE(ltc4282_gpio1_modes), func);
1287 if (ret < 0)
1288 return dev_err_probe(dev, ret,
1289 "Invalid func(%s) for gpio1\n",
1290 func);
1291
1292 ret = regmap_update_bits(st->map, LTC4282_GPIO_CONFIG,
1293 LTC4282_GPIO_1_CONFIG_MASK,
1294 FIELD_PREP(LTC4282_GPIO_1_CONFIG_MASK, ret));
1295 if (ret)
1296 return ret;
1297 }
1298
1299 ret = device_property_read_string(dev, "adi,gpio2-mode", &func);
1300 if (!ret) {
1301 ret = match_string(ltc4282_gpio2_modes,
1302 ARRAY_SIZE(ltc4282_gpio2_modes), func);
1303 if (ret < 0)
1304 return dev_err_probe(dev, ret,
1305 "Invalid func(%s) for gpio2\n",
1306 func);
1307 if (!ret) {
1308 /* setting the bit to 1 so the ADC to monitors GPIO2 */
1309 ret = regmap_set_bits(st->map, LTC4282_ILIM_ADJUST,
1310 LTC4282_GPIO_MODE_MASK);
1311 } else {
1312 ret = regmap_update_bits(st->map, LTC4282_GPIO_CONFIG,
1313 LTC4282_GPIO_2_FET_STRESS_MASK,
1314 FIELD_PREP(LTC4282_GPIO_2_FET_STRESS_MASK, 1));
1315 }
1316
1317 if (ret)
1318 return ret;
1319 }
1320
1321 if (!device_property_read_bool(dev, "adi,gpio3-monitor-enable"))
1322 return 0;
1323
1324 if (func && !strcmp(func, "adc_input"))
1325 return dev_err_probe(dev, -EINVAL,
1326 "Cannot have both gpio2 and gpio3 muxed into the ADC");
1327
1328 return regmap_clear_bits(st->map, LTC4282_ILIM_ADJUST,
1329 LTC4282_GPIO_MODE_MASK);
1330}
1331
1332static const char * const ltc4282_dividers[] = {
1333 "external", "vdd_5_percent", "vdd_10_percent", "vdd_15_percent"
1334};
1335
1336/* This maps the Vout full scale for the given Vin mode */
1337static const u16 ltc4282_vfs_milli[] = { 5540, 8320, 16640, 33280 };
1338
1339static const u16 ltc4282_vdd_milli[] = { 3300, 5000, 12000, 24000 };
1340
1341enum {
1342 LTC4282_VIN_3_3V,
1343 LTC4282_VIN_5V,
1344 LTC4282_VIN_12V,
1345 LTC4282_VIN_24V,
1346};
1347
1348static int ltc4282_setup(struct ltc4282_state *st, struct device *dev)
1349{
1350 const char *divider;
1351 u32 val, vin_mode;
1352 int ret;
1353
1354 /* The part has an eeprom so let's get the needed defaults from it */
1355 ret = ltc4282_get_defaults(st, &vin_mode);
1356 if (ret)
1357 return ret;
1358
1359 ret = device_property_read_u32(dev, "adi,rsense-nano-ohms",
1360 &st->rsense);
1361 if (ret)
1362 return dev_err_probe(dev, ret,
1363 "Failed to read adi,rsense-nano-ohms\n");
1364 if (st->rsense < CENTI)
1365 return dev_err_probe(dev, -EINVAL,
1366 "adi,rsense-nano-ohms too small (< %lu)\n",
1367 CENTI);
1368
1369 /*
1370 * The resolution for rsense is tenths of micro (eg: 62.5 uOhm) which
1371 * means we need nano in the bindings. However, to make things easier to
1372 * handle (with respect to overflows) we divide it by 100 as we don't
1373 * really need the last two digits.
1374 */
1375 st->rsense /= CENTI;
1376
1377 val = vin_mode;
1378 ret = device_property_read_u32(dev, "adi,vin-mode-microvolt", &val);
1379 if (!ret) {
1380 switch (val) {
1381 case 3300000:
1382 val = LTC4282_VIN_3_3V;
1383 break;
1384 case 5000000:
1385 val = LTC4282_VIN_5V;
1386 break;
1387 case 12000000:
1388 val = LTC4282_VIN_12V;
1389 break;
1390 case 24000000:
1391 val = LTC4282_VIN_24V;
1392 break;
1393 default:
1394 return dev_err_probe(dev, -EINVAL,
1395 "Invalid val(%u) for vin-mode-microvolt\n",
1396 val);
1397 }
1398
1399 ret = regmap_update_bits(st->map, LTC4282_CTRL_MSB,
1400 LTC4282_CTRL_VIN_MODE_MASK,
1401 FIELD_PREP(LTC4282_CTRL_VIN_MODE_MASK, val));
1402 if (ret)
1403 return ret;
1404
1405 /* Foldback mode should also be set to the input voltage */
1406 ret = regmap_update_bits(st->map, LTC4282_ILIM_ADJUST,
1407 LTC4282_FOLDBACK_MODE_MASK,
1408 FIELD_PREP(LTC4282_FOLDBACK_MODE_MASK, val));
1409 if (ret)
1410 return ret;
1411 }
1412
1413 st->vfs_out = ltc4282_vfs_milli[val];
1414 st->vdd = ltc4282_vdd_milli[val];
1415
1416 ret = device_property_read_u32(dev, "adi,current-limit-sense-microvolt",
1417 &st->vsense_max);
1418 if (!ret) {
1419 int reg_val;
1420
1421 switch (val) {
1422 case 12500:
1423 reg_val = 0;
1424 break;
1425 case 15625:
1426 reg_val = 1;
1427 break;
1428 case 18750:
1429 reg_val = 2;
1430 break;
1431 case 21875:
1432 reg_val = 3;
1433 break;
1434 case 25000:
1435 reg_val = 4;
1436 break;
1437 case 28125:
1438 reg_val = 5;
1439 break;
1440 case 31250:
1441 reg_val = 6;
1442 break;
1443 case 34375:
1444 reg_val = 7;
1445 break;
1446 default:
1447 return dev_err_probe(dev, -EINVAL,
1448 "Invalid val(%u) for adi,current-limit-microvolt\n",
1449 st->vsense_max);
1450 }
1451
1452 ret = regmap_update_bits(st->map, LTC4282_ILIM_ADJUST,
1453 LTC4282_ILIM_ADJUST_MASK,
1454 FIELD_PREP(LTC4282_ILIM_ADJUST_MASK, reg_val));
1455 if (ret)
1456 return ret;
1457 }
1458
1459 ret = ltc4282_set_max_limits(st);
1460 if (ret)
1461 return ret;
1462
1463 ret = device_property_read_string(dev, "adi,overvoltage-dividers",
1464 ÷r);
1465 if (!ret) {
1466 int div = match_string(ltc4282_dividers,
1467 ARRAY_SIZE(ltc4282_dividers), divider);
1468 if (div < 0)
1469 return dev_err_probe(dev, -EINVAL,
1470 "Invalid val(%s) for adi,overvoltage-divider\n",
1471 divider);
1472
1473 ret = regmap_update_bits(st->map, LTC4282_CTRL_MSB,
1474 LTC4282_CTRL_OV_MODE_MASK,
1475 FIELD_PREP(LTC4282_CTRL_OV_MODE_MASK, div));
1476 }
1477
1478 ret = device_property_read_string(dev, "adi,undervoltage-dividers",
1479 ÷r);
1480 if (!ret) {
1481 int div = match_string(ltc4282_dividers,
1482 ARRAY_SIZE(ltc4282_dividers), divider);
1483 if (div < 0)
1484 return dev_err_probe(dev, -EINVAL,
1485 "Invalid val(%s) for adi,undervoltage-divider\n",
1486 divider);
1487
1488 ret = regmap_update_bits(st->map, LTC4282_CTRL_MSB,
1489 LTC4282_CTRL_UV_MODE_MASK,
1490 FIELD_PREP(LTC4282_CTRL_UV_MODE_MASK, div));
1491 }
1492
1493 if (device_property_read_bool(dev, "adi,overcurrent-retry")) {
1494 ret = regmap_set_bits(st->map, LTC4282_CTRL_LSB,
1495 LTC4282_CTRL_OC_RETRY_MASK);
1496 if (ret)
1497 return ret;
1498 }
1499
1500 if (device_property_read_bool(dev, "adi,overvoltage-retry-disable")) {
1501 ret = regmap_clear_bits(st->map, LTC4282_CTRL_LSB,
1502 LTC4282_CTRL_OV_RETRY_MASK);
1503 if (ret)
1504 return ret;
1505 }
1506
1507 if (device_property_read_bool(dev, "adi,undervoltage-retry-disable")) {
1508 ret = regmap_clear_bits(st->map, LTC4282_CTRL_LSB,
1509 LTC4282_CTRL_UV_RETRY_MASK);
1510 if (ret)
1511 return ret;
1512 }
1513
1514 if (device_property_read_bool(dev, "adi,fault-log-enable")) {
1515 ret = regmap_set_bits(st->map, LTC4282_ADC_CTRL,
1516 LTC4282_FAULT_LOG_EN_MASK);
1517 if (ret)
1518 return ret;
1519 }
1520
1521 if (device_property_read_bool(dev, "adi,fault-log-enable")) {
1522 ret = regmap_set_bits(st->map, LTC4282_ADC_CTRL, LTC4282_FAULT_LOG_EN_MASK);
1523 if (ret)
1524 return ret;
1525 }
1526
1527 ret = device_property_read_u32(dev, "adi,fet-bad-timeout-ms", &val);
1528 if (!ret) {
1529 if (val > LTC4282_FET_BAD_MAX_TIMEOUT)
1530 return dev_err_probe(dev, -EINVAL,
1531 "Invalid value(%u) for adi,fet-bad-timeout-ms",
1532 val);
1533
1534 ret = regmap_write(st->map, LTC4282_FET_BAD_FAULT_TIMEOUT, val);
1535 if (ret)
1536 return ret;
1537 }
1538
1539 return ltc4282_gpio_setup(st, dev);
1540}
1541
1542static bool ltc4282_readable_reg(struct device *dev, unsigned int reg)
1543{
1544 if (reg == LTC4282_RESERVED_1 || reg == LTC4282_RESERVED_2)
1545 return false;
1546
1547 return true;
1548}
1549
1550static bool ltc4282_writable_reg(struct device *dev, unsigned int reg)
1551{
1552 if (reg == LTC4282_STATUS_LSB || reg == LTC4282_STATUS_MSB)
1553 return false;
1554 if (reg == LTC4282_RESERVED_1 || reg == LTC4282_RESERVED_2)
1555 return false;
1556
1557 return true;
1558}
1559
1560static const struct regmap_config ltc4282_regmap_config = {
1561 .reg_bits = 8,
1562 .val_bits = 8,
1563 .max_register = LTC4282_RESERVED_3,
1564 .readable_reg = ltc4282_readable_reg,
1565 .writeable_reg = ltc4282_writable_reg,
1566};
1567
1568static const struct hwmon_channel_info * const ltc4282_info[] = {
1569 HWMON_CHANNEL_INFO(in,
1570 HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
1571 HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
1572 HWMON_I_MAX_ALARM | HWMON_I_ENABLE |
1573 HWMON_I_RESET_HISTORY | HWMON_I_FAULT |
1574 HWMON_I_LABEL,
1575 HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
1576 HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
1577 HWMON_I_MAX_ALARM | HWMON_I_LCRIT_ALARM |
1578 HWMON_I_CRIT_ALARM | HWMON_I_ENABLE |
1579 HWMON_I_RESET_HISTORY | HWMON_I_LABEL,
1580 HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
1581 HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
1582 HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
1583 HWMON_I_LABEL),
1584 HWMON_CHANNEL_INFO(curr,
1585 HWMON_C_INPUT | HWMON_C_LOWEST | HWMON_C_HIGHEST |
1586 HWMON_C_MAX | HWMON_C_MIN | HWMON_C_MIN_ALARM |
1587 HWMON_C_MAX_ALARM | HWMON_C_CRIT_ALARM |
1588 HWMON_C_RESET_HISTORY | HWMON_C_LABEL),
1589 HWMON_CHANNEL_INFO(power,
1590 HWMON_P_INPUT | HWMON_P_INPUT_LOWEST |
1591 HWMON_P_INPUT_HIGHEST | HWMON_P_MAX | HWMON_P_MIN |
1592 HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
1593 HWMON_P_RESET_HISTORY | HWMON_P_LABEL),
1594 HWMON_CHANNEL_INFO(energy,
1595 HWMON_E_ENABLE),
1596 NULL
1597};
1598
1599static const struct hwmon_ops ltc4282_hwmon_ops = {
1600 .read = ltc4282_read,
1601 .write = ltc4282_write,
1602 .is_visible = ltc4282_is_visible,
1603 .read_string = ltc4282_read_labels,
1604};
1605
1606static const struct hwmon_chip_info ltc2947_chip_info = {
1607 .ops = <c4282_hwmon_ops,
1608 .info = ltc4282_info,
1609};
1610
1611/* energy attributes are 6bytes wide so we need u64 */
1612static SENSOR_DEVICE_ATTR_RO(energy1_input, ltc4282_energy, 0);
1613
1614static struct attribute *ltc4282_attrs[] = {
1615 &sensor_dev_attr_energy1_input.dev_attr.attr,
1616 NULL
1617};
1618ATTRIBUTE_GROUPS(ltc4282);
1619
1620static int ltc4282_show_fault_log(void *arg, u64 *val, u32 mask)
1621{
1622 struct ltc4282_state *st = arg;
1623 long alarm;
1624 int ret;
1625
1626 ret = ltc4282_read_alarm(st, LTC4282_FAULT_LOG, mask, &alarm);
1627 if (ret)
1628 return ret;
1629
1630 *val = alarm;
1631
1632 return 0;
1633}
1634
1635static int ltc4282_show_curr1_crit_fault_log(void *arg, u64 *val)
1636{
1637 return ltc4282_show_fault_log(arg, val, LTC4282_OC_FAULT_MASK);
1638}
1639DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_curr1_crit_fault_log,
1640 ltc4282_show_curr1_crit_fault_log, NULL, "%llu\n");
1641
1642static int ltc4282_show_in1_lcrit_fault_log(void *arg, u64 *val)
1643{
1644 return ltc4282_show_fault_log(arg, val, LTC4282_UV_FAULT_MASK);
1645}
1646DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_in1_lcrit_fault_log,
1647 ltc4282_show_in1_lcrit_fault_log, NULL, "%llu\n");
1648
1649static int ltc4282_show_in1_crit_fault_log(void *arg, u64 *val)
1650{
1651 return ltc4282_show_fault_log(arg, val, LTC4282_OV_FAULT_MASK);
1652}
1653DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_in1_crit_fault_log,
1654 ltc4282_show_in1_crit_fault_log, NULL, "%llu\n");
1655
1656static int ltc4282_show_fet_bad_fault_log(void *arg, u64 *val)
1657{
1658 return ltc4282_show_fault_log(arg, val, LTC4282_FET_BAD_FAULT_MASK);
1659}
1660DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_fet_bad_fault_log,
1661 ltc4282_show_fet_bad_fault_log, NULL, "%llu\n");
1662
1663static int ltc4282_show_fet_short_fault_log(void *arg, u64 *val)
1664{
1665 return ltc4282_show_fault_log(arg, val, LTC4282_FET_SHORT_FAULT_MASK);
1666}
1667DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_fet_short_fault_log,
1668 ltc4282_show_fet_short_fault_log, NULL, "%llu\n");
1669
1670static int ltc4282_show_power1_bad_fault_log(void *arg, u64 *val)
1671{
1672 return ltc4282_show_fault_log(arg, val, LTC4282_POWER_BAD_FAULT_MASK);
1673}
1674DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_power1_bad_fault_log,
1675 ltc4282_show_power1_bad_fault_log, NULL, "%llu\n");
1676
1677static void ltc4282_debugfs_remove(void *dir)
1678{
1679 debugfs_remove_recursive(dir);
1680}
1681
1682static void ltc4282_debugfs_init(struct ltc4282_state *st,
1683 struct i2c_client *i2c,
1684 const struct device *hwmon)
1685{
1686 const char *debugfs_name;
1687 struct dentry *dentry;
1688 int ret;
1689
1690 if (!IS_ENABLED(CONFIG_DEBUG_FS))
1691 return;
1692
1693 debugfs_name = devm_kasprintf(&i2c->dev, GFP_KERNEL, "ltc4282-%s",
1694 dev_name(hwmon));
1695 if (!debugfs_name)
1696 return;
1697
1698 dentry = debugfs_create_dir(debugfs_name, NULL);
1699 if (IS_ERR(dentry))
1700 return;
1701
1702 ret = devm_add_action_or_reset(&i2c->dev, ltc4282_debugfs_remove,
1703 dentry);
1704 if (ret)
1705 return;
1706
1707 debugfs_create_file_unsafe("power1_bad_fault_log", 0400, dentry, st,
1708 <c4282_power1_bad_fault_log);
1709 debugfs_create_file_unsafe("in0_fet_short_fault_log", 0400, dentry, st,
1710 <c4282_fet_short_fault_log);
1711 debugfs_create_file_unsafe("in0_fet_bad_fault_log", 0400, dentry, st,
1712 <c4282_fet_bad_fault_log);
1713 debugfs_create_file_unsafe("in1_crit_fault_log", 0400, dentry, st,
1714 <c4282_in1_crit_fault_log);
1715 debugfs_create_file_unsafe("in1_lcrit_fault_log", 0400, dentry, st,
1716 <c4282_in1_lcrit_fault_log);
1717 debugfs_create_file_unsafe("curr1_crit_fault_log", 0400, dentry, st,
1718 <c4282_curr1_crit_fault_log);
1719}
1720
1721static int ltc4282_probe(struct i2c_client *i2c)
1722{
1723 struct device *dev = &i2c->dev, *hwmon;
1724 struct ltc4282_state *st;
1725 int ret;
1726
1727 st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
1728 if (!st)
1729 return dev_err_probe(dev, -ENOMEM,
1730 "Failed to allocate memory\n");
1731
1732 st->map = devm_regmap_init_i2c(i2c, <c4282_regmap_config);
1733 if (IS_ERR(st->map))
1734 return dev_err_probe(dev, PTR_ERR(st->map),
1735 "failed regmap init\n");
1736
1737 /* Soft reset */
1738 ret = regmap_set_bits(st->map, LTC4282_ADC_CTRL, LTC4282_RESET_MASK);
1739 if (ret)
1740 return ret;
1741
1742 /* Yes, it's big but it is as specified in the datasheet */
1743 msleep(3200);
1744
1745 ret = ltc428_clks_setup(st, dev);
1746 if (ret)
1747 return ret;
1748
1749 ret = ltc4282_setup(st, dev);
1750 if (ret)
1751 return ret;
1752
1753 mutex_init(&st->lock);
1754 hwmon = devm_hwmon_device_register_with_info(dev, "ltc4282", st,
1755 <c2947_chip_info,
1756 ltc4282_groups);
1757 if (IS_ERR(hwmon))
1758 return PTR_ERR(hwmon);
1759
1760 ltc4282_debugfs_init(st, i2c, hwmon);
1761
1762 return 0;
1763}
1764
1765static const struct of_device_id ltc4282_of_match[] = {
1766 { .compatible = "adi,ltc4282" },
1767 {}
1768};
1769MODULE_DEVICE_TABLE(of, ltc4282_of_match);
1770
1771static struct i2c_driver ltc4282_driver = {
1772 .driver = {
1773 .name = "ltc4282",
1774 .of_match_table = ltc4282_of_match,
1775 },
1776 .probe = ltc4282_probe,
1777};
1778module_i2c_driver(ltc4282_driver);
1779
1780MODULE_AUTHOR("Nuno Sa <nuno.sa@analog.com>");
1781MODULE_DESCRIPTION("LTC4282 I2C High Current Hot Swap Controller");
1782MODULE_LICENSE("GPL");