Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
[linux-2.6-microblaze.git] / drivers / regulator / ltc3589.c
1 /*
2  * Linear Technology LTC3589,LTC3589-1 regulator support
3  *
4  * Copyright (c) 2014 Philipp Zabel <p.zabel@pengutronix.de>, Pengutronix
5  *
6  * See file CREDITS for list of people who contributed to this
7  * project.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2
11  * as published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  */
19 #include <linux/i2c.h>
20 #include <linux/init.h>
21 #include <linux/interrupt.h>
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/regmap.h>
27 #include <linux/regulator/driver.h>
28 #include <linux/regulator/of_regulator.h>
29
30 #define DRIVER_NAME             "ltc3589"
31
32 #define LTC3589_IRQSTAT         0x02
33 #define LTC3589_SCR1            0x07
34 #define LTC3589_OVEN            0x10
35 #define LTC3589_SCR2            0x12
36 #define LTC3589_PGSTAT          0x13
37 #define LTC3589_VCCR            0x20
38 #define LTC3589_CLIRQ           0x21
39 #define LTC3589_B1DTV1          0x23
40 #define LTC3589_B1DTV2          0x24
41 #define LTC3589_VRRCR           0x25
42 #define LTC3589_B2DTV1          0x26
43 #define LTC3589_B2DTV2          0x27
44 #define LTC3589_B3DTV1          0x29
45 #define LTC3589_B3DTV2          0x2a
46 #define LTC3589_L2DTV1          0x32
47 #define LTC3589_L2DTV2          0x33
48
49 #define LTC3589_IRQSTAT_PGOOD_TIMEOUT   BIT(3)
50 #define LTC3589_IRQSTAT_UNDERVOLT_WARN  BIT(4)
51 #define LTC3589_IRQSTAT_UNDERVOLT_FAULT BIT(5)
52 #define LTC3589_IRQSTAT_THERMAL_WARN    BIT(6)
53 #define LTC3589_IRQSTAT_THERMAL_FAULT   BIT(7)
54
55 #define LTC3589_OVEN_SW1                BIT(0)
56 #define LTC3589_OVEN_SW2                BIT(1)
57 #define LTC3589_OVEN_SW3                BIT(2)
58 #define LTC3589_OVEN_BB_OUT             BIT(3)
59 #define LTC3589_OVEN_LDO2               BIT(4)
60 #define LTC3589_OVEN_LDO3               BIT(5)
61 #define LTC3589_OVEN_LDO4               BIT(6)
62 #define LTC3589_OVEN_SW_CTRL            BIT(7)
63
64 #define LTC3589_VCCR_SW1_GO             BIT(0)
65 #define LTC3589_VCCR_SW2_GO             BIT(2)
66 #define LTC3589_VCCR_SW3_GO             BIT(4)
67 #define LTC3589_VCCR_LDO2_GO            BIT(6)
68
69 enum ltc3589_variant {
70         LTC3589,
71         LTC3589_1,
72         LTC3589_2,
73 };
74
75 enum ltc3589_reg {
76         LTC3589_SW1,
77         LTC3589_SW2,
78         LTC3589_SW3,
79         LTC3589_BB_OUT,
80         LTC3589_LDO1,
81         LTC3589_LDO2,
82         LTC3589_LDO3,
83         LTC3589_LDO4,
84         LTC3589_NUM_REGULATORS,
85 };
86
87 struct ltc3589_regulator {
88         struct regulator_desc desc;
89
90         /* External feedback voltage divider */
91         unsigned int r1;
92         unsigned int r2;
93 };
94
95 struct ltc3589 {
96         struct regmap *regmap;
97         struct device *dev;
98         enum ltc3589_variant variant;
99         struct ltc3589_regulator regulator_descs[LTC3589_NUM_REGULATORS];
100         struct regulator_dev *regulators[LTC3589_NUM_REGULATORS];
101 };
102
103 static const int ltc3589_ldo4[] = {
104         2800000, 2500000, 1800000, 3300000,
105 };
106
107 static const int ltc3589_12_ldo4[] = {
108         1200000, 1800000, 2500000, 3200000,
109 };
110
111 static int ltc3589_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
112 {
113         struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
114         int sel, shift;
115
116         if (unlikely(ramp_delay <= 0))
117                 return -EINVAL;
118
119         /* VRRCR slew rate offsets are the same as VCCR go bit offsets */
120         shift = ffs(rdev->desc->apply_bit) - 1;
121
122         /* The slew rate can be set to 0.88, 1.75, 3.5, or 7 mV/uS */
123         for (sel = 0; sel < 4; sel++) {
124                 if ((880 << sel) >= ramp_delay) {
125                         return regmap_update_bits(ltc3589->regmap,
126                                                   LTC3589_VRRCR,
127                                                   0x3 << shift, sel << shift);
128                 }
129         }
130         return -EINVAL;
131 }
132
133 static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV)
134 {
135         struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
136         int sel;
137
138         sel = regulator_map_voltage_linear(rdev, uV, uV);
139         if (sel < 0)
140                 return sel;
141
142         /* DTV2 register follows right after the corresponding DTV1 register */
143         return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1,
144                                   rdev->desc->vsel_mask, sel);
145 }
146
147 static int ltc3589_set_suspend_mode(struct regulator_dev *rdev,
148                                     unsigned int mode)
149 {
150         struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
151         int mask, bit = 0;
152
153         /* VCCR reference selects are right next to the VCCR go bits */
154         mask = rdev->desc->apply_bit << 1;
155
156         if (mode == REGULATOR_MODE_STANDBY)
157                 bit = mask;     /* Select DTV2 */
158
159         mask |= rdev->desc->apply_bit;
160         bit |= rdev->desc->apply_bit;
161         return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit);
162 }
163
164 /* SW1, SW2, SW3, LDO2 */
165 static const struct regulator_ops ltc3589_linear_regulator_ops = {
166         .enable = regulator_enable_regmap,
167         .disable = regulator_disable_regmap,
168         .is_enabled = regulator_is_enabled_regmap,
169         .list_voltage = regulator_list_voltage_linear,
170         .set_voltage_sel = regulator_set_voltage_sel_regmap,
171         .get_voltage_sel = regulator_get_voltage_sel_regmap,
172         .set_ramp_delay = ltc3589_set_ramp_delay,
173         .set_voltage_time_sel = regulator_set_voltage_time_sel,
174         .set_suspend_voltage = ltc3589_set_suspend_voltage,
175         .set_suspend_mode = ltc3589_set_suspend_mode,
176 };
177
178 /* BB_OUT, LDO3 */
179 static const struct regulator_ops ltc3589_fixed_regulator_ops = {
180         .enable = regulator_enable_regmap,
181         .disable = regulator_disable_regmap,
182         .is_enabled = regulator_is_enabled_regmap,
183 };
184
185 /* LDO1 */
186 static const struct regulator_ops ltc3589_fixed_standby_regulator_ops = {
187 };
188
189 /* LDO4 */
190 static const struct regulator_ops ltc3589_table_regulator_ops = {
191         .enable = regulator_enable_regmap,
192         .disable = regulator_disable_regmap,
193         .is_enabled = regulator_is_enabled_regmap,
194         .list_voltage = regulator_list_voltage_table,
195         .set_voltage_sel = regulator_set_voltage_sel_regmap,
196         .get_voltage_sel = regulator_get_voltage_sel_regmap,
197 };
198
199
200 #define LTC3589_REG(_name, _ops, en_bit, dtv1_reg, dtv_mask, go_bit)    \
201         [LTC3589_ ## _name] = {                                         \
202                 .desc = {                                               \
203                         .name = #_name,                                 \
204                         .n_voltages = (dtv_mask) + 1,                   \
205                         .min_uV = (go_bit) ? 362500 : 0,                \
206                         .uV_step = (go_bit) ? 12500 : 0,                \
207                         .ramp_delay = (go_bit) ? 1750 : 0,              \
208                         .fixed_uV = (dtv_mask) ? 0 : 800000,            \
209                         .ops = &ltc3589_ ## _ops ## _regulator_ops,     \
210                         .type = REGULATOR_VOLTAGE,                      \
211                         .id = LTC3589_ ## _name,                        \
212                         .owner = THIS_MODULE,                           \
213                         .vsel_reg = (dtv1_reg),                 \
214                         .vsel_mask = (dtv_mask),                        \
215                         .apply_reg = (go_bit) ? LTC3589_VCCR : 0,       \
216                         .apply_bit = (go_bit),                          \
217                         .enable_reg = (en_bit) ? LTC3589_OVEN : 0,      \
218                         .enable_mask = (en_bit),                        \
219                 },                                                      \
220         }
221
222 #define LTC3589_LINEAR_REG(_name, _dtv1)                                \
223         LTC3589_REG(_name, linear, LTC3589_OVEN_ ## _name,              \
224                     LTC3589_ ## _dtv1, 0x1f,                            \
225                     LTC3589_VCCR_ ## _name ## _GO)
226
227 #define LTC3589_FIXED_REG(_name) \
228         LTC3589_REG(_name, fixed, LTC3589_OVEN_ ## _name, 0, 0, 0)
229
230 static struct ltc3589_regulator ltc3589_regulators[LTC3589_NUM_REGULATORS] = {
231         LTC3589_LINEAR_REG(SW1, B1DTV1),
232         LTC3589_LINEAR_REG(SW2, B2DTV1),
233         LTC3589_LINEAR_REG(SW3, B3DTV1),
234         LTC3589_FIXED_REG(BB_OUT),
235         LTC3589_REG(LDO1, fixed_standby, 0, 0, 0, 0),
236         LTC3589_LINEAR_REG(LDO2, L2DTV1),
237         LTC3589_FIXED_REG(LDO3),
238         LTC3589_REG(LDO4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60, 0),
239 };
240
241 #ifdef CONFIG_OF
242 static struct of_regulator_match ltc3589_matches[LTC3589_NUM_REGULATORS] = {
243         { .name = "sw1",    },
244         { .name = "sw2",    },
245         { .name = "sw3",    },
246         { .name = "bb-out", },
247         { .name = "ldo1",   }, /* standby */
248         { .name = "ldo2",   },
249         { .name = "ldo3",   },
250         { .name = "ldo4",   },
251 };
252
253 static int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589)
254 {
255         struct device *dev = ltc3589->dev;
256         struct device_node *node;
257         int i, ret;
258
259         node = of_get_child_by_name(dev->of_node, "regulators");
260         if (!node) {
261                 dev_err(dev, "regulators node not found\n");
262                 return -EINVAL;
263         }
264
265         ret = of_regulator_match(dev, node, ltc3589_matches,
266                                  ARRAY_SIZE(ltc3589_matches));
267         of_node_put(node);
268         if (ret < 0) {
269                 dev_err(dev, "Error parsing regulator init data: %d\n", ret);
270                 return ret;
271         }
272         if (ret != LTC3589_NUM_REGULATORS) {
273                 dev_err(dev, "Only %d regulators described in device tree\n",
274                         ret);
275                 return -EINVAL;
276         }
277
278         /* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */
279         for (i = 0; i < LTC3589_LDO3; i++) {
280                 struct ltc3589_regulator *desc = &ltc3589->regulator_descs[i];
281                 struct device_node *np = ltc3589_matches[i].of_node;
282                 u32 vdiv[2];
283
284                 ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider",
285                                                  vdiv, 2);
286                 if (ret) {
287                         dev_err(dev, "Failed to parse voltage divider: %d\n",
288                                 ret);
289                         return ret;
290                 }
291
292                 desc->r1 = vdiv[0];
293                 desc->r2 = vdiv[1];
294         }
295
296         return 0;
297 }
298
299 static inline struct regulator_init_data *match_init_data(int index)
300 {
301         return ltc3589_matches[index].init_data;
302 }
303
304 static inline struct device_node *match_of_node(int index)
305 {
306         return ltc3589_matches[index].of_node;
307 }
308 #else
309 static inline int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589)
310 {
311         return 0;
312 }
313
314 static inline struct regulator_init_data *match_init_data(int index)
315 {
316         return NULL;
317 }
318
319 static inline struct device_node *match_of_node(int index)
320 {
321         return NULL;
322 }
323 #endif
324
325 static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg)
326 {
327         switch (reg) {
328         case LTC3589_IRQSTAT:
329         case LTC3589_SCR1:
330         case LTC3589_OVEN:
331         case LTC3589_SCR2:
332         case LTC3589_VCCR:
333         case LTC3589_CLIRQ:
334         case LTC3589_B1DTV1:
335         case LTC3589_B1DTV2:
336         case LTC3589_VRRCR:
337         case LTC3589_B2DTV1:
338         case LTC3589_B2DTV2:
339         case LTC3589_B3DTV1:
340         case LTC3589_B3DTV2:
341         case LTC3589_L2DTV1:
342         case LTC3589_L2DTV2:
343                 return true;
344         }
345         return false;
346 }
347
348 static bool ltc3589_readable_reg(struct device *dev, unsigned int reg)
349 {
350         switch (reg) {
351         case LTC3589_IRQSTAT:
352         case LTC3589_SCR1:
353         case LTC3589_OVEN:
354         case LTC3589_SCR2:
355         case LTC3589_PGSTAT:
356         case LTC3589_VCCR:
357         case LTC3589_B1DTV1:
358         case LTC3589_B1DTV2:
359         case LTC3589_VRRCR:
360         case LTC3589_B2DTV1:
361         case LTC3589_B2DTV2:
362         case LTC3589_B3DTV1:
363         case LTC3589_B3DTV2:
364         case LTC3589_L2DTV1:
365         case LTC3589_L2DTV2:
366                 return true;
367         }
368         return false;
369 }
370
371 static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg)
372 {
373         switch (reg) {
374         case LTC3589_IRQSTAT:
375         case LTC3589_PGSTAT:
376         case LTC3589_VCCR:
377                 return true;
378         }
379         return false;
380 }
381
382 static const struct reg_default ltc3589_reg_defaults[] = {
383         { LTC3589_SCR1,   0x00 },
384         { LTC3589_OVEN,   0x00 },
385         { LTC3589_SCR2,   0x00 },
386         { LTC3589_VCCR,   0x00 },
387         { LTC3589_B1DTV1, 0x19 },
388         { LTC3589_B1DTV2, 0x19 },
389         { LTC3589_VRRCR,  0xff },
390         { LTC3589_B2DTV1, 0x19 },
391         { LTC3589_B2DTV2, 0x19 },
392         { LTC3589_B3DTV1, 0x19 },
393         { LTC3589_B3DTV2, 0x19 },
394         { LTC3589_L2DTV1, 0x19 },
395         { LTC3589_L2DTV2, 0x19 },
396 };
397
398 static const struct regmap_config ltc3589_regmap_config = {
399         .reg_bits = 8,
400         .val_bits = 8,
401         .writeable_reg = ltc3589_writeable_reg,
402         .readable_reg = ltc3589_readable_reg,
403         .volatile_reg = ltc3589_volatile_reg,
404         .max_register = LTC3589_L2DTV2,
405         .reg_defaults = ltc3589_reg_defaults,
406         .num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults),
407         .use_single_rw = true,
408         .cache_type = REGCACHE_RBTREE,
409 };
410
411
412 static irqreturn_t ltc3589_isr(int irq, void *dev_id)
413 {
414         struct ltc3589 *ltc3589 = dev_id;
415         unsigned int i, irqstat, event;
416
417         regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat);
418
419         if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) {
420                 event = REGULATOR_EVENT_OVER_TEMP;
421                 for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
422                         regulator_notifier_call_chain(ltc3589->regulators[i],
423                                                       event, NULL);
424         }
425
426         if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) {
427                 event = REGULATOR_EVENT_UNDER_VOLTAGE;
428                 for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
429                         regulator_notifier_call_chain(ltc3589->regulators[i],
430                                                       event, NULL);
431         }
432
433         /* Clear warning condition */
434         regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0);
435
436         return IRQ_HANDLED;
437 }
438
439 static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2)
440 {
441         uint64_t tmp;
442         if (uV == 0)
443                 return 0;
444         tmp = (uint64_t)uV * r1;
445         do_div(tmp, r2);
446         return uV + (unsigned int)tmp;
447 }
448
449 static void ltc3589_apply_fb_voltage_divider(struct ltc3589_regulator *rdesc)
450 {
451         struct regulator_desc *desc = &rdesc->desc;
452
453         if (!rdesc->r1 || !rdesc->r2)
454                 return;
455
456         desc->min_uV = ltc3589_scale(desc->min_uV, rdesc->r1, rdesc->r2);
457         desc->uV_step = ltc3589_scale(desc->uV_step, rdesc->r1, rdesc->r2);
458         desc->fixed_uV = ltc3589_scale(desc->fixed_uV, rdesc->r1, rdesc->r2);
459 }
460
461 static int ltc3589_probe(struct i2c_client *client,
462                          const struct i2c_device_id *id)
463 {
464         struct device *dev = &client->dev;
465         struct ltc3589_regulator *descs;
466         struct ltc3589 *ltc3589;
467         int i, ret;
468
469         ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL);
470         if (!ltc3589)
471                 return -ENOMEM;
472
473         i2c_set_clientdata(client, ltc3589);
474         if (client->dev.of_node)
475                 ltc3589->variant = (enum ltc3589_variant)
476                         of_device_get_match_data(&client->dev);
477         else
478                 ltc3589->variant = id->driver_data;
479         ltc3589->dev = dev;
480
481         descs = ltc3589->regulator_descs;
482         memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators));
483         if (ltc3589->variant == LTC3589) {
484                 descs[LTC3589_LDO3].desc.fixed_uV = 1800000;
485                 descs[LTC3589_LDO4].desc.volt_table = ltc3589_ldo4;
486         } else {
487                 descs[LTC3589_LDO3].desc.fixed_uV = 2800000;
488                 descs[LTC3589_LDO4].desc.volt_table = ltc3589_12_ldo4;
489         }
490
491         ltc3589->regmap = devm_regmap_init_i2c(client, &ltc3589_regmap_config);
492         if (IS_ERR(ltc3589->regmap)) {
493                 ret = PTR_ERR(ltc3589->regmap);
494                 dev_err(dev, "failed to initialize regmap: %d\n", ret);
495                 return ret;
496         }
497
498         ret = ltc3589_parse_regulators_dt(ltc3589);
499         if (ret)
500                 return ret;
501
502         for (i = 0; i < LTC3589_NUM_REGULATORS; i++) {
503                 struct ltc3589_regulator *rdesc = &ltc3589->regulator_descs[i];
504                 struct regulator_desc *desc = &rdesc->desc;
505                 struct regulator_init_data *init_data;
506                 struct regulator_config config = { };
507
508                 init_data = match_init_data(i);
509
510                 if (i < LTC3589_LDO3)
511                         ltc3589_apply_fb_voltage_divider(rdesc);
512
513                 config.dev = dev;
514                 config.init_data = init_data;
515                 config.driver_data = ltc3589;
516                 config.of_node = match_of_node(i);
517
518                 ltc3589->regulators[i] = devm_regulator_register(dev, desc,
519                                                                  &config);
520                 if (IS_ERR(ltc3589->regulators[i])) {
521                         ret = PTR_ERR(ltc3589->regulators[i]);
522                         dev_err(dev, "failed to register regulator %s: %d\n",
523                                 desc->name, ret);
524                         return ret;
525                 }
526         }
527
528         if (client->irq) {
529                 ret = devm_request_threaded_irq(dev, client->irq, NULL,
530                                                 ltc3589_isr,
531                                                 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
532                                                 client->name, ltc3589);
533                 if (ret) {
534                         dev_err(dev, "Failed to request IRQ: %d\n", ret);
535                         return ret;
536                 }
537         }
538
539         return 0;
540 }
541
542 static const struct i2c_device_id ltc3589_i2c_id[] = {
543         { "ltc3589",   LTC3589   },
544         { "ltc3589-1", LTC3589_1 },
545         { "ltc3589-2", LTC3589_2 },
546         { }
547 };
548 MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id);
549
550 static const struct of_device_id ltc3589_of_match[] = {
551         {
552                 .compatible = "lltc,ltc3589",
553                 .data = (void *)LTC3589,
554         },
555         {
556                 .compatible = "lltc,ltc3589-1",
557                 .data = (void *)LTC3589_1,
558         },
559         {
560                 .compatible = "lltc,ltc3589-2",
561                 .data = (void *)LTC3589_2,
562         },
563         { },
564 };
565 MODULE_DEVICE_TABLE(of, ltc3589_of_match);
566
567 static struct i2c_driver ltc3589_driver = {
568         .driver = {
569                 .name = DRIVER_NAME,
570                 .of_match_table = of_match_ptr(ltc3589_of_match),
571         },
572         .probe = ltc3589_probe,
573         .id_table = ltc3589_i2c_id,
574 };
575 module_i2c_driver(ltc3589_driver);
576
577 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
578 MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)");
579 MODULE_LICENSE("GPL v2");