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-rw-r--r--drivers/regulator/ab3100.c694
1 files changed, 694 insertions, 0 deletions
diff --git a/drivers/regulator/ab3100.c b/drivers/regulator/ab3100.c
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1/*
2 * drivers/regulator/ab3100.c
3 *
4 * Copyright (C) 2008-2009 ST-Ericsson AB
5 * License terms: GNU General Public License (GPL) version 2
6 * Low-level control of the AB3100 IC Low Dropout (LDO)
7 * regulators, external regulator and buck converter
8 * Author: Mattias Wallin <mattias.wallin@stericsson.com>
9 * Author: Linus Walleij <linus.walleij@stericsson.com>
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/err.h>
16#include <linux/delay.h>
17#include <linux/platform_device.h>
18#include <linux/regulator/driver.h>
19#include <linux/mfd/ab3100.h>
20
21/* LDO registers and some handy masking definitions for AB3100 */
22#define AB3100_LDO_A 0x40
23#define AB3100_LDO_C 0x41
24#define AB3100_LDO_D 0x42
25#define AB3100_LDO_E 0x43
26#define AB3100_LDO_E_SLEEP 0x44
27#define AB3100_LDO_F 0x45
28#define AB3100_LDO_G 0x46
29#define AB3100_LDO_H 0x47
30#define AB3100_LDO_H_SLEEP_MODE 0
31#define AB3100_LDO_H_SLEEP_EN 2
32#define AB3100_LDO_ON 4
33#define AB3100_LDO_H_VSEL_AC 5
34#define AB3100_LDO_K 0x48
35#define AB3100_LDO_EXT 0x49
36#define AB3100_BUCK 0x4A
37#define AB3100_BUCK_SLEEP 0x4B
38#define AB3100_REG_ON_MASK 0x10
39
40/**
41 * struct ab3100_regulator
42 * A struct passed around the individual regulator functions
43 * @platform_device: platform device holding this regulator
44 * @ab3100: handle to the AB3100 parent chip
45 * @plfdata: AB3100 platform data passed in at probe time
46 * @regreg: regulator register number in the AB3100
47 * @fixed_voltage: a fixed voltage for this regulator, if this
48 * 0 the voltages array is used instead.
49 * @typ_voltages: an array of available typical voltages for
50 * this regulator
51 * @voltages_len: length of the array of available voltages
52 */
53struct ab3100_regulator {
54 struct regulator_dev *rdev;
55 struct ab3100 *ab3100;
56 struct ab3100_platform_data *plfdata;
57 u8 regreg;
58 int fixed_voltage;
59 int const *typ_voltages;
60 u8 voltages_len;
61};
62
63/* The order in which registers are initialized */
64static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
65 AB3100_LDO_A,
66 AB3100_LDO_C,
67 AB3100_LDO_E,
68 AB3100_LDO_E_SLEEP,
69 AB3100_LDO_F,
70 AB3100_LDO_G,
71 AB3100_LDO_H,
72 AB3100_LDO_K,
73 AB3100_LDO_EXT,
74 AB3100_BUCK,
75 AB3100_BUCK_SLEEP,
76 AB3100_LDO_D,
77};
78
79/* Preset (hardware defined) voltages for these regulators */
80#define LDO_A_VOLTAGE 2750000
81#define LDO_C_VOLTAGE 2650000
82#define LDO_D_VOLTAGE 2650000
83
84static const int const ldo_e_buck_typ_voltages[] = {
85 1800000,
86 1400000,
87 1300000,
88 1200000,
89 1100000,
90 1050000,
91 900000,
92};
93
94static const int const ldo_f_typ_voltages[] = {
95 1800000,
96 1400000,
97 1300000,
98 1200000,
99 1100000,
100 1050000,
101 2500000,
102 2650000,
103};
104
105static const int const ldo_g_typ_voltages[] = {
106 2850000,
107 2750000,
108 1800000,
109 1500000,
110};
111
112static const int const ldo_h_typ_voltages[] = {
113 2750000,
114 1800000,
115 1500000,
116 1200000,
117};
118
119static const int const ldo_k_typ_voltages[] = {
120 2750000,
121 1800000,
122};
123
124
125/* The regulator devices */
126static struct ab3100_regulator
127ab3100_regulators[AB3100_NUM_REGULATORS] = {
128 {
129 .regreg = AB3100_LDO_A,
130 .fixed_voltage = LDO_A_VOLTAGE,
131 },
132 {
133 .regreg = AB3100_LDO_C,
134 .fixed_voltage = LDO_C_VOLTAGE,
135 },
136 {
137 .regreg = AB3100_LDO_D,
138 .fixed_voltage = LDO_D_VOLTAGE,
139 },
140 {
141 .regreg = AB3100_LDO_E,
142 .typ_voltages = ldo_e_buck_typ_voltages,
143 .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
144 },
145 {
146 .regreg = AB3100_LDO_F,
147 .typ_voltages = ldo_f_typ_voltages,
148 .voltages_len = ARRAY_SIZE(ldo_f_typ_voltages),
149 },
150 {
151 .regreg = AB3100_LDO_G,
152 .typ_voltages = ldo_g_typ_voltages,
153 .voltages_len = ARRAY_SIZE(ldo_g_typ_voltages),
154 },
155 {
156 .regreg = AB3100_LDO_H,
157 .typ_voltages = ldo_h_typ_voltages,
158 .voltages_len = ARRAY_SIZE(ldo_h_typ_voltages),
159 },
160 {
161 .regreg = AB3100_LDO_K,
162 .typ_voltages = ldo_k_typ_voltages,
163 .voltages_len = ARRAY_SIZE(ldo_k_typ_voltages),
164 },
165 {
166 .regreg = AB3100_LDO_EXT,
167 /* No voltages for the external regulator */
168 },
169 {
170 .regreg = AB3100_BUCK,
171 .typ_voltages = ldo_e_buck_typ_voltages,
172 .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
173 },
174};
175
176/*
177 * General functions for enable, disable and is_enabled used for
178 * LDO: A,C,E,F,G,H,K,EXT and BUCK
179 */
180static int ab3100_enable_regulator(struct regulator_dev *reg)
181{
182 struct ab3100_regulator *abreg = reg->reg_data;
183 int err;
184 u8 regval;
185
186 err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
187 &regval);
188 if (err) {
189 dev_warn(&reg->dev, "failed to get regid %d value\n",
190 abreg->regreg);
191 return err;
192 }
193
194 /* The regulator is already on, no reason to go further */
195 if (regval & AB3100_REG_ON_MASK)
196 return 0;
197
198 regval |= AB3100_REG_ON_MASK;
199
200 err = ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
201 regval);
202 if (err) {
203 dev_warn(&reg->dev, "failed to set regid %d value\n",
204 abreg->regreg);
205 return err;
206 }
207
208 /* Per-regulator power on delay from spec */
209 switch (abreg->regreg) {
210 case AB3100_LDO_A: /* Fallthrough */
211 case AB3100_LDO_C: /* Fallthrough */
212 case AB3100_LDO_D: /* Fallthrough */
213 case AB3100_LDO_E: /* Fallthrough */
214 case AB3100_LDO_H: /* Fallthrough */
215 case AB3100_LDO_K:
216 udelay(200);
217 break;
218 case AB3100_LDO_F:
219 udelay(600);
220 break;
221 case AB3100_LDO_G:
222 udelay(400);
223 break;
224 case AB3100_BUCK:
225 mdelay(1);
226 break;
227 default:
228 break;
229 }
230
231 return 0;
232}
233
234static int ab3100_disable_regulator(struct regulator_dev *reg)
235{
236 struct ab3100_regulator *abreg = reg->reg_data;
237 int err;
238 u8 regval;
239
240 /*
241 * LDO D is a special regulator. When it is disabled, the entire
242 * system is shut down. So this is handled specially.
243 */
244 if (abreg->regreg == AB3100_LDO_D) {
245 int i;
246
247 dev_info(&reg->dev, "disabling LDO D - shut down system\n");
248 /*
249 * Set regulators to default values, ignore any errors,
250 * we're going DOWN
251 */
252 for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
253 (void) ab3100_set_register_interruptible(abreg->ab3100,
254 ab3100_reg_init_order[i],
255 abreg->plfdata->reg_initvals[i]);
256 }
257
258 /* Setting LDO D to 0x00 cuts the power to the SoC */
259 return ab3100_set_register_interruptible(abreg->ab3100,
260 AB3100_LDO_D, 0x00U);
261
262 }
263
264 /*
265 * All other regulators are handled here
266 */
267 err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
268 &regval);
269 if (err) {
270 dev_err(&reg->dev, "unable to get register 0x%x\n",
271 abreg->regreg);
272 return err;
273 }
274 regval &= ~AB3100_REG_ON_MASK;
275 return ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
276 regval);
277}
278
279static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
280{
281 struct ab3100_regulator *abreg = reg->reg_data;
282 u8 regval;
283 int err;
284
285 err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
286 &regval);
287 if (err) {
288 dev_err(&reg->dev, "unable to get register 0x%x\n",
289 abreg->regreg);
290 return err;
291 }
292
293 return regval & AB3100_REG_ON_MASK;
294}
295
296static int ab3100_list_voltage_regulator(struct regulator_dev *reg,
297 unsigned selector)
298{
299 struct ab3100_regulator *abreg = reg->reg_data;
300
301 if (selector > abreg->voltages_len)
302 return -EINVAL;
303 return abreg->typ_voltages[selector];
304}
305
306static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
307{
308 struct ab3100_regulator *abreg = reg->reg_data;
309 u8 regval;
310 int err;
311
312 /* Return the voltage for fixed regulators immediately */
313 if (abreg->fixed_voltage)
314 return abreg->fixed_voltage;
315
316 /*
317 * For variable types, read out setting and index into
318 * supplied voltage list.
319 */
320 err = ab3100_get_register_interruptible(abreg->ab3100,
321 abreg->regreg, &regval);
322 if (err) {
323 dev_warn(&reg->dev,
324 "failed to get regulator value in register %02x\n",
325 abreg->regreg);
326 return err;
327 }
328
329 /* The 3 highest bits index voltages */
330 regval &= 0xE0;
331 regval >>= 5;
332
333 if (regval > abreg->voltages_len) {
334 dev_err(&reg->dev,
335 "regulator register %02x contains an illegal voltage setting\n",
336 abreg->regreg);
337 return -EINVAL;
338 }
339
340 return abreg->typ_voltages[regval];
341}
342
343static int ab3100_get_best_voltage_index(struct regulator_dev *reg,
344 int min_uV, int max_uV)
345{
346 struct ab3100_regulator *abreg = reg->reg_data;
347 int i;
348 int bestmatch;
349 int bestindex;
350
351 /*
352 * Locate the minimum voltage fitting the criteria on
353 * this regulator. The switchable voltages are not
354 * in strict falling order so we need to check them
355 * all for the best match.
356 */
357 bestmatch = INT_MAX;
358 bestindex = -1;
359 for (i = 0; i < abreg->voltages_len; i++) {
360 if (abreg->typ_voltages[i] <= max_uV &&
361 abreg->typ_voltages[i] >= min_uV &&
362 abreg->typ_voltages[i] < bestmatch) {
363 bestmatch = abreg->typ_voltages[i];
364 bestindex = i;
365 }
366 }
367
368 if (bestindex < 0) {
369 dev_warn(&reg->dev, "requested %d<=x<=%d uV, out of range!\n",
370 min_uV, max_uV);
371 return -EINVAL;
372 }
373 return bestindex;
374}
375
376static int ab3100_set_voltage_regulator(struct regulator_dev *reg,
377 int min_uV, int max_uV)
378{
379 struct ab3100_regulator *abreg = reg->reg_data;
380 u8 regval;
381 int err;
382 int bestindex;
383
384 bestindex = ab3100_get_best_voltage_index(reg, min_uV, max_uV);
385 if (bestindex < 0)
386 return bestindex;
387
388 err = ab3100_get_register_interruptible(abreg->ab3100,
389 abreg->regreg, &regval);
390 if (err) {
391 dev_warn(&reg->dev,
392 "failed to get regulator register %02x\n",
393 abreg->regreg);
394 return err;
395 }
396
397 /* The highest three bits control the variable regulators */
398 regval &= ~0xE0;
399 regval |= (bestindex << 5);
400
401 err = ab3100_set_register_interruptible(abreg->ab3100,
402 abreg->regreg, regval);
403 if (err)
404 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
405 abreg->regreg);
406
407 return err;
408}
409
410static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
411 int uV)
412{
413 struct ab3100_regulator *abreg = reg->reg_data;
414 u8 regval;
415 int err;
416 int bestindex;
417 u8 targetreg;
418
419 if (abreg->regreg == AB3100_LDO_E)
420 targetreg = AB3100_LDO_E_SLEEP;
421 else if (abreg->regreg == AB3100_BUCK)
422 targetreg = AB3100_BUCK_SLEEP;
423 else
424 return -EINVAL;
425
426 /* LDO E and BUCK have special suspend voltages you can set */
427 bestindex = ab3100_get_best_voltage_index(reg, uV, uV);
428
429 err = ab3100_get_register_interruptible(abreg->ab3100,
430 targetreg, &regval);
431 if (err) {
432 dev_warn(&reg->dev,
433 "failed to get regulator register %02x\n",
434 targetreg);
435 return err;
436 }
437
438 /* The highest three bits control the variable regulators */
439 regval &= ~0xE0;
440 regval |= (bestindex << 5);
441
442 err = ab3100_set_register_interruptible(abreg->ab3100,
443 targetreg, regval);
444 if (err)
445 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
446 abreg->regreg);
447
448 return err;
449}
450
451/*
452 * The external regulator can just define a fixed voltage.
453 */
454static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
455{
456 struct ab3100_regulator *abreg = reg->reg_data;
457
458 return abreg->plfdata->external_voltage;
459}
460
461static struct regulator_ops regulator_ops_fixed = {
462 .enable = ab3100_enable_regulator,
463 .disable = ab3100_disable_regulator,
464 .is_enabled = ab3100_is_enabled_regulator,
465 .get_voltage = ab3100_get_voltage_regulator,
466};
467
468static struct regulator_ops regulator_ops_variable = {
469 .enable = ab3100_enable_regulator,
470 .disable = ab3100_disable_regulator,
471 .is_enabled = ab3100_is_enabled_regulator,
472 .get_voltage = ab3100_get_voltage_regulator,
473 .set_voltage = ab3100_set_voltage_regulator,
474 .list_voltage = ab3100_list_voltage_regulator,
475};
476
477static struct regulator_ops regulator_ops_variable_sleepable = {
478 .enable = ab3100_enable_regulator,
479 .disable = ab3100_disable_regulator,
480 .is_enabled = ab3100_is_enabled_regulator,
481 .get_voltage = ab3100_get_voltage_regulator,
482 .set_voltage = ab3100_set_voltage_regulator,
483 .set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
484 .list_voltage = ab3100_list_voltage_regulator,
485};
486
487/*
488 * LDO EXT is an external regulator so it is really
489 * not possible to set any voltage locally here, AB3100
490 * is an on/off switch plain an simple. The external
491 * voltage is defined in the board set-up if any.
492 */
493static struct regulator_ops regulator_ops_external = {
494 .enable = ab3100_enable_regulator,
495 .disable = ab3100_disable_regulator,
496 .is_enabled = ab3100_is_enabled_regulator,
497 .get_voltage = ab3100_get_voltage_regulator_external,
498};
499
500static struct regulator_desc
501ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
502 {
503 .name = "LDO_A",
504 .id = AB3100_LDO_A,
505 .ops = &regulator_ops_fixed,
506 .type = REGULATOR_VOLTAGE,
507 },
508 {
509 .name = "LDO_C",
510 .id = AB3100_LDO_C,
511 .ops = &regulator_ops_fixed,
512 .type = REGULATOR_VOLTAGE,
513 },
514 {
515 .name = "LDO_D",
516 .id = AB3100_LDO_D,
517 .ops = &regulator_ops_fixed,
518 .type = REGULATOR_VOLTAGE,
519 },
520 {
521 .name = "LDO_E",
522 .id = AB3100_LDO_E,
523 .ops = &regulator_ops_variable_sleepable,
524 .type = REGULATOR_VOLTAGE,
525 },
526 {
527 .name = "LDO_F",
528 .id = AB3100_LDO_F,
529 .ops = &regulator_ops_variable,
530 .type = REGULATOR_VOLTAGE,
531 },
532 {
533 .name = "LDO_G",
534 .id = AB3100_LDO_G,
535 .ops = &regulator_ops_variable,
536 .type = REGULATOR_VOLTAGE,
537 },
538 {
539 .name = "LDO_H",
540 .id = AB3100_LDO_H,
541 .ops = &regulator_ops_variable,
542 .type = REGULATOR_VOLTAGE,
543 },
544 {
545 .name = "LDO_K",
546 .id = AB3100_LDO_K,
547 .ops = &regulator_ops_variable,
548 .type = REGULATOR_VOLTAGE,
549 },
550 {
551 .name = "LDO_EXT",
552 .id = AB3100_LDO_EXT,
553 .ops = &regulator_ops_external,
554 .type = REGULATOR_VOLTAGE,
555 },
556 {
557 .name = "BUCK",
558 .id = AB3100_BUCK,
559 .ops = &regulator_ops_variable_sleepable,
560 .type = REGULATOR_VOLTAGE,
561 },
562};
563
564/*
565 * NOTE: the following functions are regulators pluralis - it is the
566 * binding to the AB3100 core driver and the parent platform device
567 * for all the different regulators.
568 */
569
570static int __init ab3100_regulators_probe(struct platform_device *pdev)
571{
572 struct ab3100_platform_data *plfdata = pdev->dev.platform_data;
573 struct ab3100 *ab3100 = platform_get_drvdata(pdev);
574 int err = 0;
575 u8 data;
576 int i;
577
578 /* Check chip state */
579 err = ab3100_get_register_interruptible(ab3100,
580 AB3100_LDO_D, &data);
581 if (err) {
582 dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
583 return err;
584 }
585 if (data & 0x10)
586 dev_notice(&pdev->dev,
587 "chip is already in active mode (Warm start)\n");
588 else
589 dev_notice(&pdev->dev,
590 "chip is in inactive mode (Cold start)\n");
591
592 /* Set up regulators */
593 for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
594 err = ab3100_set_register_interruptible(ab3100,
595 ab3100_reg_init_order[i],
596 plfdata->reg_initvals[i]);
597 if (err) {
598 dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
599 err);
600 return err;
601 }
602 }
603
604 if (err) {
605 dev_err(&pdev->dev,
606 "LDO D regulator initialization failed with error %d\n",
607 err);
608 return err;
609 }
610
611 /* Register the regulators */
612 for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
613 struct ab3100_regulator *reg = &ab3100_regulators[i];
614 struct regulator_dev *rdev;
615
616 /*
617 * Initialize per-regulator struct.
618 * Inherit platform data, this comes down from the
619 * i2c boarddata, from the machine. So if you want to
620 * see what it looks like for a certain machine, go
621 * into the machine I2C setup.
622 */
623 reg->ab3100 = ab3100;
624 reg->plfdata = plfdata;
625
626 /*
627 * Register the regulator, pass around
628 * the ab3100_regulator struct
629 */
630 rdev = regulator_register(&ab3100_regulator_desc[i],
631 &pdev->dev,
632 &plfdata->reg_constraints[i],
633 reg);
634
635 if (IS_ERR(rdev)) {
636 err = PTR_ERR(rdev);
637 dev_err(&pdev->dev,
638 "%s: failed to register regulator %s err %d\n",
639 __func__, ab3100_regulator_desc[i].name,
640 err);
641 i--;
642 /* remove the already registered regulators */
643 while (i > 0) {
644 regulator_unregister(ab3100_regulators[i].rdev);
645 i--;
646 }
647 return err;
648 }
649
650 /* Then set a pointer back to the registered regulator */
651 reg->rdev = rdev;
652 }
653
654 return 0;
655}
656
657static int __exit ab3100_regulators_remove(struct platform_device *pdev)
658{
659 int i;
660
661 for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
662 struct ab3100_regulator *reg = &ab3100_regulators[i];
663
664 regulator_unregister(reg->rdev);
665 }
666 return 0;
667}
668
669static struct platform_driver ab3100_regulators_driver = {
670 .driver = {
671 .name = "ab3100-regulators",
672 .owner = THIS_MODULE,
673 },
674 .probe = ab3100_regulators_probe,
675 .remove = __exit_p(ab3100_regulators_remove),
676};
677
678static __init int ab3100_regulators_init(void)
679{
680 return platform_driver_register(&ab3100_regulators_driver);
681}
682
683static __exit void ab3100_regulators_exit(void)
684{
685 platform_driver_register(&ab3100_regulators_driver);
686}
687
688subsys_initcall(ab3100_regulators_init);
689module_exit(ab3100_regulators_exit);
690
691MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
692MODULE_DESCRIPTION("AB3100 Regulator driver");
693MODULE_LICENSE("GPL");
694MODULE_ALIAS("platform:ab3100-regulators");