checkpatch: prefer strscpy to strlcpy
[linux-2.6-microblaze.git] / drivers / regulator / tps65090-regulator.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Regulator driver for tps65090 power management chip.
4  *
5  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
6
7  */
8
9 #include <linux/module.h>
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/of.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/slab.h>
15 #include <linux/err.h>
16 #include <linux/platform_device.h>
17 #include <linux/regulator/driver.h>
18 #include <linux/regulator/machine.h>
19 #include <linux/regulator/of_regulator.h>
20 #include <linux/mfd/tps65090.h>
21
22 #define MAX_CTRL_READ_TRIES     5
23 #define MAX_FET_ENABLE_TRIES    1000
24
25 #define CTRL_EN_BIT             0 /* Regulator enable bit, active high */
26 #define CTRL_WT_BIT             2 /* Regulator wait time 0 bit */
27 #define CTRL_PG_BIT             4 /* Regulator power good bit, 1=good */
28 #define CTRL_TO_BIT             7 /* Regulator timeout bit, 1=wait */
29
30 #define MAX_OVERCURRENT_WAIT    3 /* Overcurrent wait must be <= this */
31
32 /**
33  * struct tps65090_regulator - Per-regulator data for a tps65090 regulator
34  *
35  * @dev: Pointer to our device.
36  * @desc: The struct regulator_desc for the regulator.
37  * @rdev: The struct regulator_dev for the regulator.
38  * @overcurrent_wait_valid: True if overcurrent_wait is valid.
39  * @overcurrent_wait: For FETs, the value to put in the WTFET bitfield.
40  */
41
42 struct tps65090_regulator {
43         struct device           *dev;
44         struct regulator_desc   *desc;
45         struct regulator_dev    *rdev;
46         bool                    overcurrent_wait_valid;
47         int                     overcurrent_wait;
48 };
49
50 static const struct regulator_ops tps65090_ext_control_ops = {
51 };
52
53 /**
54  * tps65090_reg_set_overcurrent_wait - Setup overcurrent wait
55  *
56  * This will set the overcurrent wait time based on what's in the regulator
57  * info.
58  *
59  * @ri:         Overall regulator data
60  * @rdev:       Regulator device
61  *
62  * Return: 0 if no error, non-zero if there was an error writing the register.
63  */
64 static int tps65090_reg_set_overcurrent_wait(struct tps65090_regulator *ri,
65                                              struct regulator_dev *rdev)
66 {
67         int ret;
68
69         ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
70                                  MAX_OVERCURRENT_WAIT << CTRL_WT_BIT,
71                                  ri->overcurrent_wait << CTRL_WT_BIT);
72         if (ret) {
73                 dev_err(&rdev->dev, "Error updating overcurrent wait %#x\n",
74                         rdev->desc->enable_reg);
75         }
76
77         return ret;
78 }
79
80 /**
81  * tps65090_try_enable_fet - Try to enable a FET
82  *
83  * @rdev:       Regulator device
84  *
85  * Return: 0 if ok, -ENOTRECOVERABLE if the FET power good bit did not get
86  * set, or some other -ve value if another error occurred (e.g. i2c error)
87  */
88 static int tps65090_try_enable_fet(struct regulator_dev *rdev)
89 {
90         unsigned int control;
91         int ret, i;
92
93         ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
94                                  rdev->desc->enable_mask,
95                                  rdev->desc->enable_mask);
96         if (ret < 0) {
97                 dev_err(&rdev->dev, "Error in updating reg %#x\n",
98                         rdev->desc->enable_reg);
99                 return ret;
100         }
101
102         for (i = 0; i < MAX_CTRL_READ_TRIES; i++) {
103                 ret = regmap_read(rdev->regmap, rdev->desc->enable_reg,
104                                   &control);
105                 if (ret < 0)
106                         return ret;
107
108                 if (!(control & BIT(CTRL_TO_BIT)))
109                         break;
110
111                 usleep_range(1000, 1500);
112         }
113         if (!(control & BIT(CTRL_PG_BIT)))
114                 return -ENOTRECOVERABLE;
115
116         return 0;
117 }
118
119 /**
120  * tps65090_fet_enable - Enable a FET, trying a few times if it fails
121  *
122  * Some versions of the tps65090 have issues when turning on the FETs.
123  * This function goes through several steps to ensure the best chance of the
124  * FET going on.  Specifically:
125  * - We'll make sure that we bump the "overcurrent wait" to the maximum, which
126  *   increases the chances that we'll turn on properly.
127  * - We'll retry turning the FET on multiple times (turning off in between).
128  *
129  * @rdev:       Regulator device
130  *
131  * Return: 0 if ok, non-zero if it fails.
132  */
133 static int tps65090_fet_enable(struct regulator_dev *rdev)
134 {
135         int ret, tries;
136
137         /*
138          * Try enabling multiple times until we succeed since sometimes the
139          * first try times out.
140          */
141         tries = 0;
142         while (true) {
143                 ret = tps65090_try_enable_fet(rdev);
144                 if (!ret)
145                         break;
146                 if (ret != -ENOTRECOVERABLE || tries == MAX_FET_ENABLE_TRIES)
147                         goto err;
148
149                 /* Try turning the FET off (and then on again) */
150                 ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
151                                          rdev->desc->enable_mask, 0);
152                 if (ret)
153                         goto err;
154
155                 tries++;
156         }
157
158         if (tries)
159                 dev_warn(&rdev->dev, "reg %#x enable ok after %d tries\n",
160                          rdev->desc->enable_reg, tries);
161
162         return 0;
163 err:
164         dev_warn(&rdev->dev, "reg %#x enable failed\n", rdev->desc->enable_reg);
165         WARN_ON(1);
166
167         return ret;
168 }
169
170 static const struct regulator_ops tps65090_reg_control_ops = {
171         .enable         = regulator_enable_regmap,
172         .disable        = regulator_disable_regmap,
173         .is_enabled     = regulator_is_enabled_regmap,
174 };
175
176 static const struct regulator_ops tps65090_fet_control_ops = {
177         .enable         = tps65090_fet_enable,
178         .disable        = regulator_disable_regmap,
179         .is_enabled     = regulator_is_enabled_regmap,
180 };
181
182 static const struct regulator_ops tps65090_ldo_ops = {
183 };
184
185 #define tps65090_REG_DESC(_id, _sname, _en_reg, _en_bits, _nvolt, _volt, _ops) \
186 {                                                       \
187         .name = "TPS65090_RAILS"#_id,                   \
188         .supply_name = _sname,                          \
189         .id = TPS65090_REGULATOR_##_id,                 \
190         .n_voltages = _nvolt,                           \
191         .ops = &_ops,                                   \
192         .fixed_uV = _volt,                              \
193         .enable_reg = _en_reg,                          \
194         .enable_val = _en_bits,                         \
195         .enable_mask = _en_bits,                        \
196         .type = REGULATOR_VOLTAGE,                      \
197         .owner = THIS_MODULE,                           \
198 }
199
200 #define tps65090_REG_FIXEDV(_id, _sname, en_reg, _en_bits, _volt, _ops) \
201         tps65090_REG_DESC(_id, _sname, en_reg, _en_bits, 1, _volt, _ops)
202
203 #define tps65090_REG_SWITCH(_id, _sname, en_reg, _en_bits, _ops) \
204         tps65090_REG_DESC(_id, _sname, en_reg, _en_bits, 0, 0, _ops)
205
206 static struct regulator_desc tps65090_regulator_desc[] = {
207         tps65090_REG_FIXEDV(DCDC1, "vsys1",   0x0C, BIT(CTRL_EN_BIT), 5000000,
208                             tps65090_reg_control_ops),
209         tps65090_REG_FIXEDV(DCDC2, "vsys2",   0x0D, BIT(CTRL_EN_BIT), 3300000,
210                             tps65090_reg_control_ops),
211         tps65090_REG_SWITCH(DCDC3, "vsys3",   0x0E, BIT(CTRL_EN_BIT),
212                             tps65090_reg_control_ops),
213
214         tps65090_REG_SWITCH(FET1,  "infet1",  0x0F,
215                             BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
216                             tps65090_fet_control_ops),
217         tps65090_REG_SWITCH(FET2,  "infet2",  0x10,
218                             BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
219                             tps65090_fet_control_ops),
220         tps65090_REG_SWITCH(FET3,  "infet3",  0x11,
221                             BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
222                             tps65090_fet_control_ops),
223         tps65090_REG_SWITCH(FET4,  "infet4",  0x12,
224                             BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
225                             tps65090_fet_control_ops),
226         tps65090_REG_SWITCH(FET5,  "infet5",  0x13,
227                             BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
228                             tps65090_fet_control_ops),
229         tps65090_REG_SWITCH(FET6,  "infet6",  0x14,
230                             BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
231                             tps65090_fet_control_ops),
232         tps65090_REG_SWITCH(FET7,  "infet7",  0x15,
233                             BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
234                             tps65090_fet_control_ops),
235
236         tps65090_REG_FIXEDV(LDO1,  "vsys-l1", 0, 0, 5000000,
237                             tps65090_ldo_ops),
238         tps65090_REG_FIXEDV(LDO2,  "vsys-l2", 0, 0, 3300000,
239                             tps65090_ldo_ops),
240 };
241
242 static inline bool is_dcdc(int id)
243 {
244         switch (id) {
245         case TPS65090_REGULATOR_DCDC1:
246         case TPS65090_REGULATOR_DCDC2:
247         case TPS65090_REGULATOR_DCDC3:
248                 return true;
249         default:
250                 return false;
251         }
252 }
253
254 static int tps65090_config_ext_control(
255         struct tps65090_regulator *ri, bool enable)
256 {
257         int ret;
258         struct device *parent = ri->dev->parent;
259         unsigned int reg_en_reg = ri->desc->enable_reg;
260
261         if (enable)
262                 ret = tps65090_set_bits(parent, reg_en_reg, 1);
263         else
264                 ret =  tps65090_clr_bits(parent, reg_en_reg, 1);
265         if (ret < 0)
266                 dev_err(ri->dev, "Error in updating reg 0x%x\n", reg_en_reg);
267         return ret;
268 }
269
270 static int tps65090_regulator_disable_ext_control(
271                 struct tps65090_regulator *ri,
272                 struct tps65090_regulator_plat_data *tps_pdata)
273 {
274         int ret = 0;
275         struct device *parent = ri->dev->parent;
276         unsigned int reg_en_reg = ri->desc->enable_reg;
277
278         /*
279          * First enable output for internal control if require.
280          * And then disable external control.
281          */
282         if (tps_pdata->reg_init_data->constraints.always_on ||
283                         tps_pdata->reg_init_data->constraints.boot_on) {
284                 ret =  tps65090_set_bits(parent, reg_en_reg, 0);
285                 if (ret < 0) {
286                         dev_err(ri->dev, "Error in set reg 0x%x\n", reg_en_reg);
287                         return ret;
288                 }
289         }
290         return tps65090_config_ext_control(ri, false);
291 }
292
293 #ifdef CONFIG_OF
294 static struct of_regulator_match tps65090_matches[] = {
295         { .name = "dcdc1", },
296         { .name = "dcdc2", },
297         { .name = "dcdc3", },
298         { .name = "fet1",  },
299         { .name = "fet2",  },
300         { .name = "fet3",  },
301         { .name = "fet4",  },
302         { .name = "fet5",  },
303         { .name = "fet6",  },
304         { .name = "fet7",  },
305         { .name = "ldo1",  },
306         { .name = "ldo2",  },
307 };
308
309 static struct tps65090_platform_data *tps65090_parse_dt_reg_data(
310                 struct platform_device *pdev,
311                 struct of_regulator_match **tps65090_reg_matches)
312 {
313         struct tps65090_platform_data *tps65090_pdata;
314         struct device_node *np = pdev->dev.parent->of_node;
315         struct device_node *regulators;
316         int idx = 0, ret;
317         struct tps65090_regulator_plat_data *reg_pdata;
318
319         tps65090_pdata = devm_kzalloc(&pdev->dev, sizeof(*tps65090_pdata),
320                                 GFP_KERNEL);
321         if (!tps65090_pdata)
322                 return ERR_PTR(-ENOMEM);
323
324         reg_pdata = devm_kcalloc(&pdev->dev,
325                                  TPS65090_REGULATOR_MAX, sizeof(*reg_pdata),
326                                  GFP_KERNEL);
327         if (!reg_pdata)
328                 return ERR_PTR(-ENOMEM);
329
330         regulators = of_get_child_by_name(np, "regulators");
331         if (!regulators) {
332                 dev_err(&pdev->dev, "regulator node not found\n");
333                 return ERR_PTR(-ENODEV);
334         }
335
336         ret = of_regulator_match(&pdev->dev, regulators, tps65090_matches,
337                         ARRAY_SIZE(tps65090_matches));
338         of_node_put(regulators);
339         if (ret < 0) {
340                 dev_err(&pdev->dev,
341                         "Error parsing regulator init data: %d\n", ret);
342                 return ERR_PTR(ret);
343         }
344
345         *tps65090_reg_matches = tps65090_matches;
346         for (idx = 0; idx < ARRAY_SIZE(tps65090_matches); idx++) {
347                 struct regulator_init_data *ri_data;
348                 struct tps65090_regulator_plat_data *rpdata;
349                 struct device_node *np;
350
351                 rpdata = &reg_pdata[idx];
352                 ri_data = tps65090_matches[idx].init_data;
353                 if (!ri_data)
354                         continue;
355
356                 np = tps65090_matches[idx].of_node;
357                 if (!np)
358                         continue;
359
360                 rpdata->reg_init_data = ri_data;
361                 rpdata->enable_ext_control = of_property_read_bool(np,
362                                                 "ti,enable-ext-control");
363                 if (rpdata->enable_ext_control) {
364                         enum gpiod_flags gflags;
365
366                         if (ri_data->constraints.always_on ||
367                             ri_data->constraints.boot_on)
368                                 gflags = GPIOD_OUT_HIGH;
369                         else
370                                 gflags = GPIOD_OUT_LOW;
371                         gflags |= GPIOD_FLAGS_BIT_NONEXCLUSIVE;
372
373                         rpdata->gpiod = devm_fwnode_gpiod_get(
374                                                         &pdev->dev,
375                                                         of_fwnode_handle(np),
376                                                         "dcdc-ext-control",
377                                                         gflags,
378                                                         "tps65090");
379                         if (PTR_ERR(rpdata->gpiod) == -ENOENT) {
380                                 dev_err(&pdev->dev,
381                                         "could not find DCDC external control GPIO\n");
382                                 rpdata->gpiod = NULL;
383                         } else if (IS_ERR(rpdata->gpiod))
384                                 return ERR_CAST(rpdata->gpiod);
385                 }
386
387                 if (of_property_read_u32(np, "ti,overcurrent-wait",
388                                          &rpdata->overcurrent_wait) == 0)
389                         rpdata->overcurrent_wait_valid = true;
390
391                 tps65090_pdata->reg_pdata[idx] = rpdata;
392         }
393         return tps65090_pdata;
394 }
395 #else
396 static inline struct tps65090_platform_data *tps65090_parse_dt_reg_data(
397                         struct platform_device *pdev,
398                         struct of_regulator_match **tps65090_reg_matches)
399 {
400         *tps65090_reg_matches = NULL;
401         return NULL;
402 }
403 #endif
404
405 static int tps65090_regulator_probe(struct platform_device *pdev)
406 {
407         struct tps65090 *tps65090_mfd = dev_get_drvdata(pdev->dev.parent);
408         struct tps65090_regulator *ri = NULL;
409         struct regulator_config config = { };
410         struct regulator_dev *rdev;
411         struct tps65090_regulator_plat_data *tps_pdata;
412         struct tps65090_regulator *pmic;
413         struct tps65090_platform_data *tps65090_pdata;
414         struct of_regulator_match *tps65090_reg_matches = NULL;
415         int num;
416         int ret;
417
418         dev_dbg(&pdev->dev, "Probing regulator\n");
419
420         tps65090_pdata = dev_get_platdata(pdev->dev.parent);
421         if (!tps65090_pdata && tps65090_mfd->dev->of_node)
422                 tps65090_pdata = tps65090_parse_dt_reg_data(pdev,
423                                         &tps65090_reg_matches);
424         if (IS_ERR_OR_NULL(tps65090_pdata)) {
425                 dev_err(&pdev->dev, "Platform data missing\n");
426                 return tps65090_pdata ? PTR_ERR(tps65090_pdata) : -EINVAL;
427         }
428
429         pmic = devm_kcalloc(&pdev->dev,
430                             TPS65090_REGULATOR_MAX, sizeof(*pmic),
431                             GFP_KERNEL);
432         if (!pmic)
433                 return -ENOMEM;
434
435         for (num = 0; num < TPS65090_REGULATOR_MAX; num++) {
436                 tps_pdata = tps65090_pdata->reg_pdata[num];
437
438                 ri = &pmic[num];
439                 ri->dev = &pdev->dev;
440                 ri->desc = &tps65090_regulator_desc[num];
441                 if (tps_pdata) {
442                         ri->overcurrent_wait_valid =
443                                 tps_pdata->overcurrent_wait_valid;
444                         ri->overcurrent_wait = tps_pdata->overcurrent_wait;
445                 }
446
447                 /*
448                  * TPS5090 DCDC support the control from external digital input.
449                  * Configure it as per platform data.
450                  */
451                 if (tps_pdata && is_dcdc(num) && tps_pdata->reg_init_data) {
452                         if (tps_pdata->enable_ext_control) {
453                                 config.ena_gpiod = tps_pdata->gpiod;
454                                 ri->desc->ops = &tps65090_ext_control_ops;
455                         } else {
456                                 ret = tps65090_regulator_disable_ext_control(
457                                                 ri, tps_pdata);
458                                 if (ret < 0) {
459                                         dev_err(&pdev->dev,
460                                                 "failed disable ext control\n");
461                                         return ret;
462                                 }
463                         }
464                 }
465
466                 config.dev = pdev->dev.parent;
467                 config.driver_data = ri;
468                 config.regmap = tps65090_mfd->rmap;
469                 if (tps_pdata)
470                         config.init_data = tps_pdata->reg_init_data;
471                 else
472                         config.init_data = NULL;
473                 if (tps65090_reg_matches)
474                         config.of_node = tps65090_reg_matches[num].of_node;
475                 else
476                         config.of_node = NULL;
477
478                 /*
479                  * Hand the GPIO descriptor management over to the regulator
480                  * core, remove it from devres management.
481                  */
482                 if (config.ena_gpiod)
483                         devm_gpiod_unhinge(&pdev->dev, config.ena_gpiod);
484                 rdev = devm_regulator_register(&pdev->dev, ri->desc, &config);
485                 if (IS_ERR(rdev)) {
486                         dev_err(&pdev->dev, "failed to register regulator %s\n",
487                                 ri->desc->name);
488                         return PTR_ERR(rdev);
489                 }
490                 ri->rdev = rdev;
491
492                 if (ri->overcurrent_wait_valid) {
493                         ret = tps65090_reg_set_overcurrent_wait(ri, rdev);
494                         if (ret < 0)
495                                 return ret;
496                 }
497
498                 /* Enable external control if it is require */
499                 if (tps_pdata && is_dcdc(num) && tps_pdata->reg_init_data &&
500                                 tps_pdata->enable_ext_control) {
501                         ret = tps65090_config_ext_control(ri, true);
502                         if (ret < 0)
503                                 return ret;
504                 }
505         }
506
507         platform_set_drvdata(pdev, pmic);
508         return 0;
509 }
510
511 static struct platform_driver tps65090_regulator_driver = {
512         .driver = {
513                 .name   = "tps65090-pmic",
514         },
515         .probe          = tps65090_regulator_probe,
516 };
517
518 static int __init tps65090_regulator_init(void)
519 {
520         return platform_driver_register(&tps65090_regulator_driver);
521 }
522 subsys_initcall(tps65090_regulator_init);
523
524 static void __exit tps65090_regulator_exit(void)
525 {
526         platform_driver_unregister(&tps65090_regulator_driver);
527 }
528 module_exit(tps65090_regulator_exit);
529
530 MODULE_DESCRIPTION("tps65090 regulator driver");
531 MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");
532 MODULE_LICENSE("GPL v2");
533 MODULE_ALIAS("platform:tps65090-pmic");