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