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");
534