1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // MCP16502 PMIC driver
4 //
5 // Copyright (C) 2018 Microchip Technology Inc. and its subsidiaries
6 //
7 // Author: Andrei Stefanescu <andrei.stefanescu@microchip.com>
8 //
9 // Inspired from tps65086-regulator.c
10
11 #include <linux/i2c.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/regmap.h>
17 #include <linux/regulator/driver.h>
18 #include <linux/suspend.h>
19 #include <linux/gpio/consumer.h>
20
21 #define VDD_LOW_SEL 0x0D
22 #define VDD_HIGH_SEL 0x3F
23
24 #define MCP16502_FLT BIT(7)
25 #define MCP16502_DVSR GENMASK(3, 2)
26 #define MCP16502_ENS BIT(0)
27
28 /*
29 * The PMIC has four sets of registers corresponding to four power modes:
30 * Performance, Active, Low-power, Hibernate.
31 *
32 * Registers:
33 * Each regulator has a register for each power mode. To access a register
34 * for a specific regulator and mode BASE_* and OFFSET_* need to be added.
35 *
36 * Operating modes:
37 * In order for the PMIC to transition to operating modes it has to be
38 * controlled via GPIO lines called LPM and HPM.
39 *
40 * The registers are fully configurable such that you can put all regulators in
41 * a low-power state while the PMIC is in Active mode. They are supposed to be
42 * configured at startup and then simply transition to/from a global low-power
43 * state by setting the GPIO lpm pin high/low.
44 *
45 * This driver keeps the PMIC in Active mode, Low-power state is set for the
46 * regulators by enabling/disabling operating mode (FPWM or Auto PFM).
47 *
48 * The PMIC's Low-power and Hibernate modes are used during standby/suspend.
49 * To enter standby/suspend the PMIC will go to Low-power mode. From there, it
50 * will transition to Hibernate when the PWRHLD line is set to low by the MPU.
51 */
52
53 /*
54 * This function is useful for iterating over all regulators and accessing their
55 * registers in a generic way or accessing a regulator device by its id.
56 */
57 #define MCP16502_REG_BASE(i, r) ((((i) + 1) << 4) + MCP16502_REG_##r)
58 #define MCP16502_STAT_BASE(i) ((i) + 5)
59
60 #define MCP16502_OPMODE_ACTIVE REGULATOR_MODE_NORMAL
61 #define MCP16502_OPMODE_LPM REGULATOR_MODE_IDLE
62 #define MCP16502_OPMODE_HIB REGULATOR_MODE_STANDBY
63
64 #define MCP16502_MODE_AUTO_PFM 0
65 #define MCP16502_MODE_FPWM BIT(6)
66
67 #define MCP16502_VSEL 0x3F
68 #define MCP16502_EN BIT(7)
69 #define MCP16502_MODE BIT(6)
70
71 #define MCP16502_MIN_REG 0x0
72 #define MCP16502_MAX_REG 0x65
73
74 /**
75 * enum mcp16502_reg - MCP16502 regulators's registers
76 * @MCP16502_REG_A: active state register
77 * @MCP16502_REG_LPM: low power mode state register
78 * @MCP16502_REG_HIB: hibernate state register
79 * @MCP16502_REG_HPM: high-performance mode register
80 * @MCP16502_REG_SEQ: startup sequence register
81 * @MCP16502_REG_CFG: configuration register
82 */
83 enum mcp16502_reg {
84 MCP16502_REG_A,
85 MCP16502_REG_LPM,
86 MCP16502_REG_HIB,
87 MCP16502_REG_HPM,
88 MCP16502_REG_SEQ,
89 MCP16502_REG_CFG,
90 };
91
92 /* Ramp delay (uV/us) for buck1, ldo1, ldo2. */
93 static const unsigned int mcp16502_ramp_b1l12[] = {
94 6250, 3125, 2083, 1563
95 };
96
97 /* Ramp delay (uV/us) for buck2, buck3, buck4. */
98 static const unsigned int mcp16502_ramp_b234[] = {
99 3125, 1563, 1042, 781
100 };
101
mcp16502_of_map_mode(unsigned int mode)102 static unsigned int mcp16502_of_map_mode(unsigned int mode)
103 {
104 if (mode == REGULATOR_MODE_NORMAL || mode == REGULATOR_MODE_IDLE)
105 return mode;
106
107 return REGULATOR_MODE_INVALID;
108 }
109
110 #define MCP16502_REGULATOR(_name, _id, _ranges, _ops, _ramp_table) \
111 [_id] = { \
112 .name = _name, \
113 .regulators_node = "regulators", \
114 .id = _id, \
115 .ops = &(_ops), \
116 .type = REGULATOR_VOLTAGE, \
117 .owner = THIS_MODULE, \
118 .n_voltages = MCP16502_VSEL + 1, \
119 .linear_ranges = _ranges, \
120 .linear_min_sel = VDD_LOW_SEL, \
121 .n_linear_ranges = ARRAY_SIZE(_ranges), \
122 .of_match = _name, \
123 .of_map_mode = mcp16502_of_map_mode, \
124 .vsel_reg = (((_id) + 1) << 4), \
125 .vsel_mask = MCP16502_VSEL, \
126 .enable_reg = (((_id) + 1) << 4), \
127 .enable_mask = MCP16502_EN, \
128 .ramp_reg = MCP16502_REG_BASE(_id, CFG), \
129 .ramp_mask = MCP16502_DVSR, \
130 .ramp_delay_table = _ramp_table, \
131 .n_ramp_values = ARRAY_SIZE(_ramp_table), \
132 }
133
134 enum {
135 BUCK1 = 0,
136 BUCK2,
137 BUCK3,
138 BUCK4,
139 LDO1,
140 LDO2,
141 NUM_REGULATORS
142 };
143
144 /*
145 * struct mcp16502 - PMIC representation
146 * @lpm: LPM GPIO descriptor
147 */
148 struct mcp16502 {
149 struct gpio_desc *lpm;
150 };
151
152 /*
153 * mcp16502_gpio_set_mode() - set the GPIO corresponding value
154 *
155 * Used to prepare transitioning into hibernate or resuming from it.
156 */
mcp16502_gpio_set_mode(struct mcp16502 * mcp,int mode)157 static void mcp16502_gpio_set_mode(struct mcp16502 *mcp, int mode)
158 {
159 switch (mode) {
160 case MCP16502_OPMODE_ACTIVE:
161 gpiod_set_value(mcp->lpm, 0);
162 break;
163 case MCP16502_OPMODE_LPM:
164 case MCP16502_OPMODE_HIB:
165 gpiod_set_value(mcp->lpm, 1);
166 break;
167 default:
168 pr_err("%s: %d invalid\n", __func__, mode);
169 }
170 }
171
172 /*
173 * mcp16502_get_reg() - get the PMIC's state configuration register for opmode
174 *
175 * @rdev: the regulator whose register we are searching
176 * @opmode: the PMIC's operating mode ACTIVE, Low-power, Hibernate
177 */
mcp16502_get_state_reg(struct regulator_dev * rdev,int opmode)178 static int mcp16502_get_state_reg(struct regulator_dev *rdev, int opmode)
179 {
180 switch (opmode) {
181 case MCP16502_OPMODE_ACTIVE:
182 return MCP16502_REG_BASE(rdev_get_id(rdev), A);
183 case MCP16502_OPMODE_LPM:
184 return MCP16502_REG_BASE(rdev_get_id(rdev), LPM);
185 case MCP16502_OPMODE_HIB:
186 return MCP16502_REG_BASE(rdev_get_id(rdev), HIB);
187 default:
188 return -EINVAL;
189 }
190 }
191
192 /*
193 * mcp16502_get_mode() - return the current operating mode of a regulator
194 *
195 * Note: all functions that are not part of entering/exiting standby/suspend
196 * use the Active mode registers.
197 *
198 * Note: this is different from the PMIC's operatig mode, it is the
199 * MODE bit from the regulator's register.
200 */
mcp16502_get_mode(struct regulator_dev * rdev)201 static unsigned int mcp16502_get_mode(struct regulator_dev *rdev)
202 {
203 unsigned int val;
204 int ret, reg;
205
206 reg = mcp16502_get_state_reg(rdev, MCP16502_OPMODE_ACTIVE);
207 if (reg < 0)
208 return reg;
209
210 ret = regmap_read(rdev->regmap, reg, &val);
211 if (ret)
212 return ret;
213
214 switch (val & MCP16502_MODE) {
215 case MCP16502_MODE_FPWM:
216 return REGULATOR_MODE_NORMAL;
217 case MCP16502_MODE_AUTO_PFM:
218 return REGULATOR_MODE_IDLE;
219 default:
220 return REGULATOR_MODE_INVALID;
221 }
222 }
223
224 /*
225 * _mcp16502_set_mode() - helper for set_mode and set_suspend_mode
226 *
227 * @rdev: the regulator for which we are setting the mode
228 * @mode: the regulator's mode (the one from MODE bit)
229 * @opmode: the PMIC's operating mode: Active/Low-power/Hibernate
230 */
_mcp16502_set_mode(struct regulator_dev * rdev,unsigned int mode,unsigned int op_mode)231 static int _mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode,
232 unsigned int op_mode)
233 {
234 int val;
235 int reg;
236
237 reg = mcp16502_get_state_reg(rdev, op_mode);
238 if (reg < 0)
239 return reg;
240
241 switch (mode) {
242 case REGULATOR_MODE_NORMAL:
243 val = MCP16502_MODE_FPWM;
244 break;
245 case REGULATOR_MODE_IDLE:
246 val = MCP16502_MODE_AUTO_PFM;
247 break;
248 default:
249 return -EINVAL;
250 }
251
252 reg = regmap_update_bits(rdev->regmap, reg, MCP16502_MODE, val);
253 return reg;
254 }
255
256 /*
257 * mcp16502_set_mode() - regulator_ops set_mode
258 */
mcp16502_set_mode(struct regulator_dev * rdev,unsigned int mode)259 static int mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode)
260 {
261 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_ACTIVE);
262 }
263
264 /*
265 * mcp16502_get_status() - regulator_ops get_status
266 */
mcp16502_get_status(struct regulator_dev * rdev)267 static int mcp16502_get_status(struct regulator_dev *rdev)
268 {
269 int ret;
270 unsigned int val;
271
272 ret = regmap_read(rdev->regmap, MCP16502_STAT_BASE(rdev_get_id(rdev)),
273 &val);
274 if (ret)
275 return ret;
276
277 if (val & MCP16502_FLT)
278 return REGULATOR_STATUS_ERROR;
279 else if (val & MCP16502_ENS)
280 return REGULATOR_STATUS_ON;
281 else if (!(val & MCP16502_ENS))
282 return REGULATOR_STATUS_OFF;
283
284 return REGULATOR_STATUS_UNDEFINED;
285 }
286
mcp16502_set_voltage_time_sel(struct regulator_dev * rdev,unsigned int old_sel,unsigned int new_sel)287 static int mcp16502_set_voltage_time_sel(struct regulator_dev *rdev,
288 unsigned int old_sel,
289 unsigned int new_sel)
290 {
291 static const u8 us_ramp[] = { 8, 16, 24, 32 };
292 int id = rdev_get_id(rdev);
293 unsigned int uV_delta, val;
294 int ret;
295
296 ret = regmap_read(rdev->regmap, MCP16502_REG_BASE(id, CFG), &val);
297 if (ret)
298 return ret;
299
300 val = (val & MCP16502_DVSR) >> 2;
301 uV_delta = abs(new_sel * rdev->desc->linear_ranges->step -
302 old_sel * rdev->desc->linear_ranges->step);
303 switch (id) {
304 case BUCK1:
305 case LDO1:
306 case LDO2:
307 ret = DIV_ROUND_CLOSEST(uV_delta * us_ramp[val],
308 mcp16502_ramp_b1l12[val]);
309 break;
310
311 case BUCK2:
312 case BUCK3:
313 case BUCK4:
314 ret = DIV_ROUND_CLOSEST(uV_delta * us_ramp[val],
315 mcp16502_ramp_b234[val]);
316 break;
317
318 default:
319 return -EINVAL;
320 }
321
322 return ret;
323 }
324
325 #ifdef CONFIG_SUSPEND
326 /*
327 * mcp16502_suspend_get_target_reg() - get the reg of the target suspend PMIC
328 * mode
329 */
mcp16502_suspend_get_target_reg(struct regulator_dev * rdev)330 static int mcp16502_suspend_get_target_reg(struct regulator_dev *rdev)
331 {
332 switch (pm_suspend_target_state) {
333 case PM_SUSPEND_STANDBY:
334 return mcp16502_get_state_reg(rdev, MCP16502_OPMODE_LPM);
335 case PM_SUSPEND_ON:
336 case PM_SUSPEND_MEM:
337 return mcp16502_get_state_reg(rdev, MCP16502_OPMODE_HIB);
338 default:
339 dev_err(&rdev->dev, "invalid suspend target: %d\n",
340 pm_suspend_target_state);
341 }
342
343 return -EINVAL;
344 }
345
346 /*
347 * mcp16502_set_suspend_voltage() - regulator_ops set_suspend_voltage
348 */
mcp16502_set_suspend_voltage(struct regulator_dev * rdev,int uV)349 static int mcp16502_set_suspend_voltage(struct regulator_dev *rdev, int uV)
350 {
351 int sel = regulator_map_voltage_linear_range(rdev, uV, uV);
352 int reg = mcp16502_suspend_get_target_reg(rdev);
353
354 if (sel < 0)
355 return sel;
356
357 if (reg < 0)
358 return reg;
359
360 return regmap_update_bits(rdev->regmap, reg, MCP16502_VSEL, sel);
361 }
362
363 /*
364 * mcp16502_set_suspend_mode() - regulator_ops set_suspend_mode
365 */
mcp16502_set_suspend_mode(struct regulator_dev * rdev,unsigned int mode)366 static int mcp16502_set_suspend_mode(struct regulator_dev *rdev,
367 unsigned int mode)
368 {
369 switch (pm_suspend_target_state) {
370 case PM_SUSPEND_STANDBY:
371 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_LPM);
372 case PM_SUSPEND_ON:
373 case PM_SUSPEND_MEM:
374 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_HIB);
375 default:
376 dev_err(&rdev->dev, "invalid suspend target: %d\n",
377 pm_suspend_target_state);
378 }
379
380 return -EINVAL;
381 }
382
383 /*
384 * mcp16502_set_suspend_enable() - regulator_ops set_suspend_enable
385 */
mcp16502_set_suspend_enable(struct regulator_dev * rdev)386 static int mcp16502_set_suspend_enable(struct regulator_dev *rdev)
387 {
388 int reg = mcp16502_suspend_get_target_reg(rdev);
389
390 if (reg < 0)
391 return reg;
392
393 return regmap_update_bits(rdev->regmap, reg, MCP16502_EN, MCP16502_EN);
394 }
395
396 /*
397 * mcp16502_set_suspend_disable() - regulator_ops set_suspend_disable
398 */
mcp16502_set_suspend_disable(struct regulator_dev * rdev)399 static int mcp16502_set_suspend_disable(struct regulator_dev *rdev)
400 {
401 int reg = mcp16502_suspend_get_target_reg(rdev);
402
403 if (reg < 0)
404 return reg;
405
406 return regmap_update_bits(rdev->regmap, reg, MCP16502_EN, 0);
407 }
408 #endif /* CONFIG_SUSPEND */
409
410 static const struct regulator_ops mcp16502_buck_ops = {
411 .list_voltage = regulator_list_voltage_linear_range,
412 .map_voltage = regulator_map_voltage_linear_range,
413 .get_voltage_sel = regulator_get_voltage_sel_regmap,
414 .set_voltage_sel = regulator_set_voltage_sel_regmap,
415 .enable = regulator_enable_regmap,
416 .disable = regulator_disable_regmap,
417 .is_enabled = regulator_is_enabled_regmap,
418 .get_status = mcp16502_get_status,
419 .set_voltage_time_sel = mcp16502_set_voltage_time_sel,
420 .set_ramp_delay = regulator_set_ramp_delay_regmap,
421
422 .set_mode = mcp16502_set_mode,
423 .get_mode = mcp16502_get_mode,
424
425 #ifdef CONFIG_SUSPEND
426 .set_suspend_voltage = mcp16502_set_suspend_voltage,
427 .set_suspend_mode = mcp16502_set_suspend_mode,
428 .set_suspend_enable = mcp16502_set_suspend_enable,
429 .set_suspend_disable = mcp16502_set_suspend_disable,
430 #endif /* CONFIG_SUSPEND */
431 };
432
433 /*
434 * LDOs cannot change operating modes.
435 */
436 static const struct regulator_ops mcp16502_ldo_ops = {
437 .list_voltage = regulator_list_voltage_linear_range,
438 .map_voltage = regulator_map_voltage_linear_range,
439 .get_voltage_sel = regulator_get_voltage_sel_regmap,
440 .set_voltage_sel = regulator_set_voltage_sel_regmap,
441 .enable = regulator_enable_regmap,
442 .disable = regulator_disable_regmap,
443 .is_enabled = regulator_is_enabled_regmap,
444 .get_status = mcp16502_get_status,
445 .set_voltage_time_sel = mcp16502_set_voltage_time_sel,
446 .set_ramp_delay = regulator_set_ramp_delay_regmap,
447
448 #ifdef CONFIG_SUSPEND
449 .set_suspend_voltage = mcp16502_set_suspend_voltage,
450 .set_suspend_enable = mcp16502_set_suspend_enable,
451 .set_suspend_disable = mcp16502_set_suspend_disable,
452 #endif /* CONFIG_SUSPEND */
453 };
454
455 static const struct of_device_id mcp16502_ids[] = {
456 { .compatible = "microchip,mcp16502", },
457 {}
458 };
459 MODULE_DEVICE_TABLE(of, mcp16502_ids);
460
461 static const struct linear_range b1l12_ranges[] = {
462 REGULATOR_LINEAR_RANGE(1200000, VDD_LOW_SEL, VDD_HIGH_SEL, 50000),
463 };
464
465 static const struct linear_range b234_ranges[] = {
466 REGULATOR_LINEAR_RANGE(600000, VDD_LOW_SEL, VDD_HIGH_SEL, 25000),
467 };
468
469 static const struct regulator_desc mcp16502_desc[] = {
470 /* MCP16502_REGULATOR(_name, _id, ranges, regulator_ops, ramp_table) */
471 MCP16502_REGULATOR("VDD_IO", BUCK1, b1l12_ranges, mcp16502_buck_ops,
472 mcp16502_ramp_b1l12),
473 MCP16502_REGULATOR("VDD_DDR", BUCK2, b234_ranges, mcp16502_buck_ops,
474 mcp16502_ramp_b234),
475 MCP16502_REGULATOR("VDD_CORE", BUCK3, b234_ranges, mcp16502_buck_ops,
476 mcp16502_ramp_b234),
477 MCP16502_REGULATOR("VDD_OTHER", BUCK4, b234_ranges, mcp16502_buck_ops,
478 mcp16502_ramp_b234),
479 MCP16502_REGULATOR("LDO1", LDO1, b1l12_ranges, mcp16502_ldo_ops,
480 mcp16502_ramp_b1l12),
481 MCP16502_REGULATOR("LDO2", LDO2, b1l12_ranges, mcp16502_ldo_ops,
482 mcp16502_ramp_b1l12)
483 };
484
485 static const struct regmap_range mcp16502_ranges[] = {
486 regmap_reg_range(MCP16502_MIN_REG, MCP16502_MAX_REG)
487 };
488
489 static const struct regmap_access_table mcp16502_yes_reg_table = {
490 .yes_ranges = mcp16502_ranges,
491 .n_yes_ranges = ARRAY_SIZE(mcp16502_ranges),
492 };
493
494 static const struct regmap_config mcp16502_regmap_config = {
495 .reg_bits = 8,
496 .val_bits = 8,
497 .max_register = MCP16502_MAX_REG,
498 .cache_type = REGCACHE_NONE,
499 .rd_table = &mcp16502_yes_reg_table,
500 .wr_table = &mcp16502_yes_reg_table,
501 };
502
mcp16502_probe(struct i2c_client * client)503 static int mcp16502_probe(struct i2c_client *client)
504 {
505 struct regulator_config config = { };
506 struct regulator_dev *rdev;
507 struct device *dev;
508 struct mcp16502 *mcp;
509 struct regmap *rmap;
510 int i, ret;
511
512 dev = &client->dev;
513 config.dev = dev;
514
515 mcp = devm_kzalloc(dev, sizeof(*mcp), GFP_KERNEL);
516 if (!mcp)
517 return -ENOMEM;
518
519 rmap = devm_regmap_init_i2c(client, &mcp16502_regmap_config);
520 if (IS_ERR(rmap)) {
521 ret = PTR_ERR(rmap);
522 dev_err(dev, "regmap init failed: %d\n", ret);
523 return ret;
524 }
525
526 i2c_set_clientdata(client, mcp);
527 config.regmap = rmap;
528 config.driver_data = mcp;
529
530 mcp->lpm = devm_gpiod_get_optional(dev, "lpm", GPIOD_OUT_LOW);
531 if (IS_ERR(mcp->lpm)) {
532 dev_err(dev, "failed to get lpm pin: %ld\n", PTR_ERR(mcp->lpm));
533 return PTR_ERR(mcp->lpm);
534 }
535
536 for (i = 0; i < NUM_REGULATORS; i++) {
537 rdev = devm_regulator_register(dev, &mcp16502_desc[i], &config);
538 if (IS_ERR(rdev)) {
539 dev_err(dev,
540 "failed to register %s regulator %ld\n",
541 mcp16502_desc[i].name, PTR_ERR(rdev));
542 return PTR_ERR(rdev);
543 }
544 }
545
546 mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
547
548 return 0;
549 }
550
551 #ifdef CONFIG_PM_SLEEP
mcp16502_suspend_noirq(struct device * dev)552 static int mcp16502_suspend_noirq(struct device *dev)
553 {
554 struct i2c_client *client = to_i2c_client(dev);
555 struct mcp16502 *mcp = i2c_get_clientdata(client);
556
557 mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_LPM);
558
559 return 0;
560 }
561
mcp16502_resume_noirq(struct device * dev)562 static int mcp16502_resume_noirq(struct device *dev)
563 {
564 struct i2c_client *client = to_i2c_client(dev);
565 struct mcp16502 *mcp = i2c_get_clientdata(client);
566
567 mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
568
569 return 0;
570 }
571 #endif
572
573 #ifdef CONFIG_PM
574 static const struct dev_pm_ops mcp16502_pm_ops = {
575 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mcp16502_suspend_noirq,
576 mcp16502_resume_noirq)
577 };
578 #endif
579 static const struct i2c_device_id mcp16502_i2c_id[] = {
580 { "mcp16502", 0 },
581 { }
582 };
583 MODULE_DEVICE_TABLE(i2c, mcp16502_i2c_id);
584
585 static struct i2c_driver mcp16502_drv = {
586 .probe = mcp16502_probe,
587 .driver = {
588 .name = "mcp16502-regulator",
589 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
590 .of_match_table = mcp16502_ids,
591 #ifdef CONFIG_PM
592 .pm = &mcp16502_pm_ops,
593 #endif
594 },
595 .id_table = mcp16502_i2c_id,
596 };
597
598 module_i2c_driver(mcp16502_drv);
599
600 MODULE_LICENSE("GPL v2");
601 MODULE_DESCRIPTION("MCP16502 PMIC driver");
602 MODULE_AUTHOR("Andrei Stefanescu andrei.stefanescu@microchip.com");
603
