Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
[pandora-kernel.git] / drivers / regulator / ab3100.c
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/abx500.h>
20 #include <linux/mfd/core.h>
21
22 /* LDO registers and some handy masking definitions for AB3100 */
23 #define AB3100_LDO_A            0x40
24 #define AB3100_LDO_C            0x41
25 #define AB3100_LDO_D            0x42
26 #define AB3100_LDO_E            0x43
27 #define AB3100_LDO_E_SLEEP      0x44
28 #define AB3100_LDO_F            0x45
29 #define AB3100_LDO_G            0x46
30 #define AB3100_LDO_H            0x47
31 #define AB3100_LDO_H_SLEEP_MODE 0
32 #define AB3100_LDO_H_SLEEP_EN   2
33 #define AB3100_LDO_ON           4
34 #define AB3100_LDO_H_VSEL_AC    5
35 #define AB3100_LDO_K            0x48
36 #define AB3100_LDO_EXT          0x49
37 #define AB3100_BUCK             0x4A
38 #define AB3100_BUCK_SLEEP       0x4B
39 #define AB3100_REG_ON_MASK      0x10
40
41 /**
42  * struct ab3100_regulator
43  * A struct passed around the individual regulator functions
44  * @platform_device: platform device holding this regulator
45  * @dev: handle to the device
46  * @plfdata: AB3100 platform data passed in at probe time
47  * @regreg: regulator register number in the AB3100
48  * @fixed_voltage: a fixed voltage for this regulator, if this
49  *          0 the voltages array is used instead.
50  * @typ_voltages: an array of available typical voltages for
51  *          this regulator
52  * @voltages_len: length of the array of available voltages
53  */
54 struct ab3100_regulator {
55         struct regulator_dev *rdev;
56         struct device *dev;
57         struct ab3100_platform_data *plfdata;
58         u8 regreg;
59         int fixed_voltage;
60         int const *typ_voltages;
61         u8 voltages_len;
62 };
63
64 /* The order in which registers are initialized */
65 static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
66         AB3100_LDO_A,
67         AB3100_LDO_C,
68         AB3100_LDO_E,
69         AB3100_LDO_E_SLEEP,
70         AB3100_LDO_F,
71         AB3100_LDO_G,
72         AB3100_LDO_H,
73         AB3100_LDO_K,
74         AB3100_LDO_EXT,
75         AB3100_BUCK,
76         AB3100_BUCK_SLEEP,
77         AB3100_LDO_D,
78 };
79
80 /* Preset (hardware defined) voltages for these regulators */
81 #define LDO_A_VOLTAGE 2750000
82 #define LDO_C_VOLTAGE 2650000
83 #define LDO_D_VOLTAGE 2650000
84
85 static const int ldo_e_buck_typ_voltages[] = {
86         1800000,
87         1400000,
88         1300000,
89         1200000,
90         1100000,
91         1050000,
92         900000,
93 };
94
95 static const int ldo_f_typ_voltages[] = {
96         1800000,
97         1400000,
98         1300000,
99         1200000,
100         1100000,
101         1050000,
102         2500000,
103         2650000,
104 };
105
106 static const int ldo_g_typ_voltages[] = {
107         2850000,
108         2750000,
109         1800000,
110         1500000,
111 };
112
113 static const int ldo_h_typ_voltages[] = {
114         2750000,
115         1800000,
116         1500000,
117         1200000,
118 };
119
120 static const int ldo_k_typ_voltages[] = {
121         2750000,
122         1800000,
123 };
124
125
126 /* The regulator devices */
127 static struct ab3100_regulator
128 ab3100_regulators[AB3100_NUM_REGULATORS] = {
129         {
130                 .regreg = AB3100_LDO_A,
131                 .fixed_voltage = LDO_A_VOLTAGE,
132         },
133         {
134                 .regreg = AB3100_LDO_C,
135                 .fixed_voltage = LDO_C_VOLTAGE,
136         },
137         {
138                 .regreg = AB3100_LDO_D,
139                 .fixed_voltage = LDO_D_VOLTAGE,
140         },
141         {
142                 .regreg = AB3100_LDO_E,
143                 .typ_voltages = ldo_e_buck_typ_voltages,
144                 .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
145         },
146         {
147                 .regreg = AB3100_LDO_F,
148                 .typ_voltages = ldo_f_typ_voltages,
149                 .voltages_len = ARRAY_SIZE(ldo_f_typ_voltages),
150         },
151         {
152                 .regreg = AB3100_LDO_G,
153                 .typ_voltages = ldo_g_typ_voltages,
154                 .voltages_len = ARRAY_SIZE(ldo_g_typ_voltages),
155         },
156         {
157                 .regreg = AB3100_LDO_H,
158                 .typ_voltages = ldo_h_typ_voltages,
159                 .voltages_len = ARRAY_SIZE(ldo_h_typ_voltages),
160         },
161         {
162                 .regreg = AB3100_LDO_K,
163                 .typ_voltages = ldo_k_typ_voltages,
164                 .voltages_len = ARRAY_SIZE(ldo_k_typ_voltages),
165         },
166         {
167                 .regreg = AB3100_LDO_EXT,
168                 /* No voltages for the external regulator */
169         },
170         {
171                 .regreg = AB3100_BUCK,
172                 .typ_voltages = ldo_e_buck_typ_voltages,
173                 .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
174         },
175 };
176
177 /*
178  * General functions for enable, disable and is_enabled used for
179  * LDO: A,C,E,F,G,H,K,EXT and BUCK
180  */
181 static int ab3100_enable_regulator(struct regulator_dev *reg)
182 {
183         struct ab3100_regulator *abreg = reg->reg_data;
184         int err;
185         u8 regval;
186
187         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
188                                                 &regval);
189         if (err) {
190                 dev_warn(&reg->dev, "failed to get regid %d value\n",
191                          abreg->regreg);
192                 return err;
193         }
194
195         /* The regulator is already on, no reason to go further */
196         if (regval & AB3100_REG_ON_MASK)
197                 return 0;
198
199         regval |= AB3100_REG_ON_MASK;
200
201         err = abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
202                                                 regval);
203         if (err) {
204                 dev_warn(&reg->dev, "failed to set regid %d value\n",
205                          abreg->regreg);
206                 return err;
207         }
208
209         /* Per-regulator power on delay from spec */
210         switch (abreg->regreg) {
211         case AB3100_LDO_A: /* Fallthrough */
212         case AB3100_LDO_C: /* Fallthrough */
213         case AB3100_LDO_D: /* Fallthrough */
214         case AB3100_LDO_E: /* Fallthrough */
215         case AB3100_LDO_H: /* Fallthrough */
216         case AB3100_LDO_K:
217                 udelay(200);
218                 break;
219         case AB3100_LDO_F:
220                 udelay(600);
221                 break;
222         case AB3100_LDO_G:
223                 udelay(400);
224                 break;
225         case AB3100_BUCK:
226                 mdelay(1);
227                 break;
228         default:
229                 break;
230         }
231
232         return 0;
233 }
234
235 static int ab3100_disable_regulator(struct regulator_dev *reg)
236 {
237         struct ab3100_regulator *abreg = reg->reg_data;
238         int err;
239         u8 regval;
240
241         /*
242          * LDO D is a special regulator. When it is disabled, the entire
243          * system is shut down. So this is handled specially.
244          */
245         pr_info("Called ab3100_disable_regulator\n");
246         if (abreg->regreg == AB3100_LDO_D) {
247                 dev_info(&reg->dev, "disabling LDO D - shut down system\n");
248                 /* Setting LDO D to 0x00 cuts the power to the SoC */
249                 return abx500_set_register_interruptible(abreg->dev, 0,
250                                                          AB3100_LDO_D, 0x00U);
251         }
252
253         /*
254          * All other regulators are handled here
255          */
256         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
257                                                 &regval);
258         if (err) {
259                 dev_err(&reg->dev, "unable to get register 0x%x\n",
260                         abreg->regreg);
261                 return err;
262         }
263         regval &= ~AB3100_REG_ON_MASK;
264         return abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
265                                                  regval);
266 }
267
268 static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
269 {
270         struct ab3100_regulator *abreg = reg->reg_data;
271         u8 regval;
272         int err;
273
274         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
275                                                 &regval);
276         if (err) {
277                 dev_err(&reg->dev, "unable to get register 0x%x\n",
278                         abreg->regreg);
279                 return err;
280         }
281
282         return regval & AB3100_REG_ON_MASK;
283 }
284
285 static int ab3100_list_voltage_regulator(struct regulator_dev *reg,
286                                          unsigned selector)
287 {
288         struct ab3100_regulator *abreg = reg->reg_data;
289
290         if (selector >= abreg->voltages_len)
291                 return -EINVAL;
292         return abreg->typ_voltages[selector];
293 }
294
295 static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
296 {
297         struct ab3100_regulator *abreg = reg->reg_data;
298         u8 regval;
299         int err;
300
301         /* Return the voltage for fixed regulators immediately */
302         if (abreg->fixed_voltage)
303                 return abreg->fixed_voltage;
304
305         /*
306          * For variable types, read out setting and index into
307          * supplied voltage list.
308          */
309         err = abx500_get_register_interruptible(abreg->dev, 0,
310                                                 abreg->regreg, &regval);
311         if (err) {
312                 dev_warn(&reg->dev,
313                          "failed to get regulator value in register %02x\n",
314                          abreg->regreg);
315                 return err;
316         }
317
318         /* The 3 highest bits index voltages */
319         regval &= 0xE0;
320         regval >>= 5;
321
322         if (regval >= abreg->voltages_len) {
323                 dev_err(&reg->dev,
324                         "regulator register %02x contains an illegal voltage setting\n",
325                         abreg->regreg);
326                 return -EINVAL;
327         }
328
329         return abreg->typ_voltages[regval];
330 }
331
332 static int ab3100_get_best_voltage_index(struct regulator_dev *reg,
333                                    int min_uV, int max_uV)
334 {
335         struct ab3100_regulator *abreg = reg->reg_data;
336         int i;
337         int bestmatch;
338         int bestindex;
339
340         /*
341          * Locate the minimum voltage fitting the criteria on
342          * this regulator. The switchable voltages are not
343          * in strict falling order so we need to check them
344          * all for the best match.
345          */
346         bestmatch = INT_MAX;
347         bestindex = -1;
348         for (i = 0; i < abreg->voltages_len; i++) {
349                 if (abreg->typ_voltages[i] <= max_uV &&
350                     abreg->typ_voltages[i] >= min_uV &&
351                     abreg->typ_voltages[i] < bestmatch) {
352                         bestmatch = abreg->typ_voltages[i];
353                         bestindex = i;
354                 }
355         }
356
357         if (bestindex < 0) {
358                 dev_warn(&reg->dev, "requested %d<=x<=%d uV, out of range!\n",
359                          min_uV, max_uV);
360                 return -EINVAL;
361         }
362         return bestindex;
363 }
364
365 static int ab3100_set_voltage_regulator(struct regulator_dev *reg,
366                                         int min_uV, int max_uV,
367                                         unsigned *selector)
368 {
369         struct ab3100_regulator *abreg = reg->reg_data;
370         u8 regval;
371         int err;
372         int bestindex;
373
374         bestindex = ab3100_get_best_voltage_index(reg, min_uV, max_uV);
375         if (bestindex < 0)
376                 return bestindex;
377
378         *selector = bestindex;
379
380         err = abx500_get_register_interruptible(abreg->dev, 0,
381                                                 abreg->regreg, &regval);
382         if (err) {
383                 dev_warn(&reg->dev,
384                          "failed to get regulator register %02x\n",
385                          abreg->regreg);
386                 return err;
387         }
388
389         /* The highest three bits control the variable regulators */
390         regval &= ~0xE0;
391         regval |= (bestindex << 5);
392
393         err = abx500_set_register_interruptible(abreg->dev, 0,
394                                                 abreg->regreg, regval);
395         if (err)
396                 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
397                         abreg->regreg);
398
399         return err;
400 }
401
402 static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
403                                                 int uV)
404 {
405         struct ab3100_regulator *abreg = reg->reg_data;
406         u8 regval;
407         int err;
408         int bestindex;
409         u8 targetreg;
410
411         if (abreg->regreg == AB3100_LDO_E)
412                 targetreg = AB3100_LDO_E_SLEEP;
413         else if (abreg->regreg == AB3100_BUCK)
414                 targetreg = AB3100_BUCK_SLEEP;
415         else
416                 return -EINVAL;
417
418         /* LDO E and BUCK have special suspend voltages you can set */
419         bestindex = ab3100_get_best_voltage_index(reg, uV, uV);
420
421         err = abx500_get_register_interruptible(abreg->dev, 0,
422                                                 targetreg, &regval);
423         if (err) {
424                 dev_warn(&reg->dev,
425                          "failed to get regulator register %02x\n",
426                          targetreg);
427                 return err;
428         }
429
430         /* The highest three bits control the variable regulators */
431         regval &= ~0xE0;
432         regval |= (bestindex << 5);
433
434         err = abx500_set_register_interruptible(abreg->dev, 0,
435                                                 targetreg, regval);
436         if (err)
437                 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
438                         abreg->regreg);
439
440         return err;
441 }
442
443 /*
444  * The external regulator can just define a fixed voltage.
445  */
446 static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
447 {
448         struct ab3100_regulator *abreg = reg->reg_data;
449
450         return abreg->plfdata->external_voltage;
451 }
452
453 static struct regulator_ops regulator_ops_fixed = {
454         .enable      = ab3100_enable_regulator,
455         .disable     = ab3100_disable_regulator,
456         .is_enabled  = ab3100_is_enabled_regulator,
457         .get_voltage = ab3100_get_voltage_regulator,
458 };
459
460 static struct regulator_ops regulator_ops_variable = {
461         .enable      = ab3100_enable_regulator,
462         .disable     = ab3100_disable_regulator,
463         .is_enabled  = ab3100_is_enabled_regulator,
464         .get_voltage = ab3100_get_voltage_regulator,
465         .set_voltage = ab3100_set_voltage_regulator,
466         .list_voltage = ab3100_list_voltage_regulator,
467 };
468
469 static struct regulator_ops regulator_ops_variable_sleepable = {
470         .enable      = ab3100_enable_regulator,
471         .disable     = ab3100_disable_regulator,
472         .is_enabled  = ab3100_is_enabled_regulator,
473         .get_voltage = ab3100_get_voltage_regulator,
474         .set_voltage = ab3100_set_voltage_regulator,
475         .set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
476         .list_voltage = ab3100_list_voltage_regulator,
477 };
478
479 /*
480  * LDO EXT is an external regulator so it is really
481  * not possible to set any voltage locally here, AB3100
482  * is an on/off switch plain an simple. The external
483  * voltage is defined in the board set-up if any.
484  */
485 static struct regulator_ops regulator_ops_external = {
486         .enable      = ab3100_enable_regulator,
487         .disable     = ab3100_disable_regulator,
488         .is_enabled  = ab3100_is_enabled_regulator,
489         .get_voltage = ab3100_get_voltage_regulator_external,
490 };
491
492 static struct regulator_desc
493 ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
494         {
495                 .name = "LDO_A",
496                 .id   = AB3100_LDO_A,
497                 .ops  = &regulator_ops_fixed,
498                 .type = REGULATOR_VOLTAGE,
499                 .owner = THIS_MODULE,
500         },
501         {
502                 .name = "LDO_C",
503                 .id   = AB3100_LDO_C,
504                 .ops  = &regulator_ops_fixed,
505                 .type = REGULATOR_VOLTAGE,
506                 .owner = THIS_MODULE,
507         },
508         {
509                 .name = "LDO_D",
510                 .id   = AB3100_LDO_D,
511                 .ops  = &regulator_ops_fixed,
512                 .type = REGULATOR_VOLTAGE,
513                 .owner = THIS_MODULE,
514         },
515         {
516                 .name = "LDO_E",
517                 .id   = AB3100_LDO_E,
518                 .ops  = &regulator_ops_variable_sleepable,
519                 .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
520                 .type = REGULATOR_VOLTAGE,
521                 .owner = THIS_MODULE,
522         },
523         {
524                 .name = "LDO_F",
525                 .id   = AB3100_LDO_F,
526                 .ops  = &regulator_ops_variable,
527                 .n_voltages = ARRAY_SIZE(ldo_f_typ_voltages),
528                 .type = REGULATOR_VOLTAGE,
529                 .owner = THIS_MODULE,
530         },
531         {
532                 .name = "LDO_G",
533                 .id   = AB3100_LDO_G,
534                 .ops  = &regulator_ops_variable,
535                 .n_voltages = ARRAY_SIZE(ldo_g_typ_voltages),
536                 .type = REGULATOR_VOLTAGE,
537                 .owner = THIS_MODULE,
538         },
539         {
540                 .name = "LDO_H",
541                 .id   = AB3100_LDO_H,
542                 .ops  = &regulator_ops_variable,
543                 .n_voltages = ARRAY_SIZE(ldo_h_typ_voltages),
544                 .type = REGULATOR_VOLTAGE,
545                 .owner = THIS_MODULE,
546         },
547         {
548                 .name = "LDO_K",
549                 .id   = AB3100_LDO_K,
550                 .ops  = &regulator_ops_variable,
551                 .n_voltages = ARRAY_SIZE(ldo_k_typ_voltages),
552                 .type = REGULATOR_VOLTAGE,
553                 .owner = THIS_MODULE,
554         },
555         {
556                 .name = "LDO_EXT",
557                 .id   = AB3100_LDO_EXT,
558                 .ops  = &regulator_ops_external,
559                 .type = REGULATOR_VOLTAGE,
560                 .owner = THIS_MODULE,
561         },
562         {
563                 .name = "BUCK",
564                 .id   = AB3100_BUCK,
565                 .ops  = &regulator_ops_variable_sleepable,
566                 .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
567                 .type = REGULATOR_VOLTAGE,
568                 .owner = THIS_MODULE,
569         },
570 };
571
572 /*
573  * NOTE: the following functions are regulators pluralis - it is the
574  * binding to the AB3100 core driver and the parent platform device
575  * for all the different regulators.
576  */
577
578 static int __devinit ab3100_regulators_probe(struct platform_device *pdev)
579 {
580         struct ab3100_platform_data *plfdata = mfd_get_data(pdev);
581         int err = 0;
582         u8 data;
583         int i;
584
585         /* Check chip state */
586         err = abx500_get_register_interruptible(&pdev->dev, 0,
587                                                 AB3100_LDO_D, &data);
588         if (err) {
589                 dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
590                 return err;
591         }
592         if (data & 0x10)
593                 dev_notice(&pdev->dev,
594                            "chip is already in active mode (Warm start)\n");
595         else
596                 dev_notice(&pdev->dev,
597                            "chip is in inactive mode (Cold start)\n");
598
599         /* Set up regulators */
600         for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
601                 err = abx500_set_register_interruptible(&pdev->dev, 0,
602                                         ab3100_reg_init_order[i],
603                                         plfdata->reg_initvals[i]);
604                 if (err) {
605                         dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
606                                 err);
607                         return err;
608                 }
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->dev = &pdev->dev;
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                         /* remove the already registered regulators */
642                         while (--i >= 0)
643                                 regulator_unregister(ab3100_regulators[i].rdev);
644                         return err;
645                 }
646
647                 /* Then set a pointer back to the registered regulator */
648                 reg->rdev = rdev;
649         }
650
651         return 0;
652 }
653
654 static int __devexit ab3100_regulators_remove(struct platform_device *pdev)
655 {
656         int i;
657
658         for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
659                 struct ab3100_regulator *reg = &ab3100_regulators[i];
660
661                 regulator_unregister(reg->rdev);
662         }
663         return 0;
664 }
665
666 static struct platform_driver ab3100_regulators_driver = {
667         .driver = {
668                 .name  = "ab3100-regulators",
669                 .owner = THIS_MODULE,
670         },
671         .probe = ab3100_regulators_probe,
672         .remove = __devexit_p(ab3100_regulators_remove),
673 };
674
675 static __init int ab3100_regulators_init(void)
676 {
677         return platform_driver_register(&ab3100_regulators_driver);
678 }
679
680 static __exit void ab3100_regulators_exit(void)
681 {
682         platform_driver_unregister(&ab3100_regulators_driver);
683 }
684
685 subsys_initcall(ab3100_regulators_init);
686 module_exit(ab3100_regulators_exit);
687
688 MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
689 MODULE_DESCRIPTION("AB3100 Regulator driver");
690 MODULE_LICENSE("GPL");
691 MODULE_ALIAS("platform:ab3100-regulators");