1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * tps62360.c -- TI tps62360
4  *
5  * Driver for processor core supply tps62360, tps62361B, tps62362 and tps62363.
6  *
7  * Copyright (c) 2012, NVIDIA Corporation.
8  *
9  * Author: Laxman Dewangan <ldewangan@nvidia.com>
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/err.h>
16 #include <linux/of.h>
17 #include <linux/of_device.h>
18 #include <linux/regulator/of_regulator.h>
19 #include <linux/platform_device.h>
20 #include <linux/regulator/driver.h>
21 #include <linux/regulator/machine.h>
22 #include <linux/regulator/tps62360.h>
23 #include <linux/gpio/consumer.h>
24 #include <linux/i2c.h>
25 #include <linux/slab.h>
26 #include <linux/regmap.h>
27 
28 /* Register definitions */
29 #define REG_VSET0		0
30 #define REG_VSET1		1
31 #define REG_VSET2		2
32 #define REG_VSET3		3
33 #define REG_CONTROL		4
34 #define REG_TEMP		5
35 #define REG_RAMPCTRL		6
36 #define REG_CHIPID		8
37 
38 #define FORCE_PWM_ENABLE	BIT(7)
39 
40 enum chips {TPS62360, TPS62361, TPS62362, TPS62363};
41 
42 #define TPS62360_BASE_VOLTAGE	770000
43 #define TPS62360_N_VOLTAGES	64
44 
45 #define TPS62361_BASE_VOLTAGE	500000
46 #define TPS62361_N_VOLTAGES	128
47 
48 /* tps 62360 chip information */
49 struct tps62360_chip {
50 	struct device *dev;
51 	struct regulator_desc desc;
52 	struct regulator_dev *rdev;
53 	struct regmap *regmap;
54 	struct gpio_desc *vsel0_gpio;
55 	struct gpio_desc *vsel1_gpio;
56 	u8 voltage_reg_mask;
57 	bool en_internal_pulldn;
58 	bool en_discharge;
59 	bool valid_gpios;
60 	int lru_index[4];
61 	int curr_vset_vsel[4];
62 	int curr_vset_id;
63 };
64 
65 /*
66  * find_voltage_set_register: Find new voltage configuration register
67  * (VSET) id.
68  * The finding of the new VSET register will be based on the LRU mechanism.
69  * Each VSET register will have different voltage configured . This
70  * Function will look if any of the VSET register have requested voltage set
71  * or not.
72  *     - If it is already there then it will make that register as most
73  *       recently used and return as found so that caller need not to set
74  *       the VSET register but need to set the proper gpios to select this
75  *       VSET register.
76  *     - If requested voltage is not found then it will use the least
77  *       recently mechanism to get new VSET register for new configuration
78  *       and will return not_found so that caller need to set new VSET
79  *       register and then gpios (both).
80  */
81 static bool find_voltage_set_register(struct tps62360_chip *tps,
82 		int req_vsel, int *vset_reg_id)
83 {
84 	int i;
85 	bool found = false;
86 	int new_vset_reg = tps->lru_index[3];
87 	int found_index = 3;
88 
89 	for (i = 0; i < 4; ++i) {
90 		if (tps->curr_vset_vsel[tps->lru_index[i]] == req_vsel) {
91 			new_vset_reg = tps->lru_index[i];
92 			found_index = i;
93 			found = true;
94 			goto update_lru_index;
95 		}
96 	}
97 
98 update_lru_index:
99 	for (i = found_index; i > 0; i--)
100 		tps->lru_index[i] = tps->lru_index[i - 1];
101 
102 	tps->lru_index[0] = new_vset_reg;
103 	*vset_reg_id = new_vset_reg;
104 	return found;
105 }
106 
107 static int tps62360_dcdc_get_voltage_sel(struct regulator_dev *dev)
108 {
109 	struct tps62360_chip *tps = rdev_get_drvdata(dev);
110 	int vsel;
111 	unsigned int data;
112 	int ret;
113 
114 	ret = regmap_read(tps->regmap, REG_VSET0 + tps->curr_vset_id, &data);
115 	if (ret < 0) {
116 		dev_err(tps->dev, "%s(): register %d read failed with err %d\n",
117 			__func__, REG_VSET0 + tps->curr_vset_id, ret);
118 		return ret;
119 	}
120 	vsel = (int)data & tps->voltage_reg_mask;
121 	return vsel;
122 }
123 
124 static int tps62360_dcdc_set_voltage_sel(struct regulator_dev *dev,
125 					 unsigned selector)
126 {
127 	struct tps62360_chip *tps = rdev_get_drvdata(dev);
128 	int ret;
129 	bool found = false;
130 	int new_vset_id = tps->curr_vset_id;
131 
132 	/*
133 	 * If gpios are available to select the VSET register then least
134 	 * recently used register for new configuration.
135 	 */
136 	if (tps->valid_gpios)
137 		found = find_voltage_set_register(tps, selector, &new_vset_id);
138 
139 	if (!found) {
140 		ret = regmap_update_bits(tps->regmap, REG_VSET0 + new_vset_id,
141 				tps->voltage_reg_mask, selector);
142 		if (ret < 0) {
143 			dev_err(tps->dev,
144 				"%s(): register %d update failed with err %d\n",
145 				 __func__, REG_VSET0 + new_vset_id, ret);
146 			return ret;
147 		}
148 		tps->curr_vset_id = new_vset_id;
149 		tps->curr_vset_vsel[new_vset_id] = selector;
150 	}
151 
152 	/* Select proper VSET register vio gpios */
153 	if (tps->valid_gpios) {
154 		gpiod_set_value_cansleep(tps->vsel0_gpio, new_vset_id & 0x1);
155 		gpiod_set_value_cansleep(tps->vsel1_gpio,
156 					(new_vset_id >> 1) & 0x1);
157 	}
158 	return 0;
159 }
160 
161 static int tps62360_set_mode(struct regulator_dev *rdev, unsigned int mode)
162 {
163 	struct tps62360_chip *tps = rdev_get_drvdata(rdev);
164 	int i;
165 	int val;
166 	int ret;
167 
168 	/* Enable force PWM mode in FAST mode only. */
169 	switch (mode) {
170 	case REGULATOR_MODE_FAST:
171 		val = FORCE_PWM_ENABLE;
172 		break;
173 
174 	case REGULATOR_MODE_NORMAL:
175 		val = 0;
176 		break;
177 
178 	default:
179 		return -EINVAL;
180 	}
181 
182 	if (!tps->valid_gpios) {
183 		ret = regmap_update_bits(tps->regmap,
184 			REG_VSET0 + tps->curr_vset_id, FORCE_PWM_ENABLE, val);
185 		if (ret < 0)
186 			dev_err(tps->dev,
187 				"%s(): register %d update failed with err %d\n",
188 				__func__, REG_VSET0 + tps->curr_vset_id, ret);
189 		return ret;
190 	}
191 
192 	/* If gpios are valid then all register set need to be control */
193 	for (i = 0; i < 4; ++i) {
194 		ret = regmap_update_bits(tps->regmap,
195 					REG_VSET0 + i, FORCE_PWM_ENABLE, val);
196 		if (ret < 0) {
197 			dev_err(tps->dev,
198 				"%s(): register %d update failed with err %d\n",
199 				__func__, REG_VSET0 + i, ret);
200 			return ret;
201 		}
202 	}
203 	return ret;
204 }
205 
206 static unsigned int tps62360_get_mode(struct regulator_dev *rdev)
207 {
208 	struct tps62360_chip *tps = rdev_get_drvdata(rdev);
209 	unsigned int data;
210 	int ret;
211 
212 	ret = regmap_read(tps->regmap, REG_VSET0 + tps->curr_vset_id, &data);
213 	if (ret < 0) {
214 		dev_err(tps->dev, "%s(): register %d read failed with err %d\n",
215 			__func__, REG_VSET0 + tps->curr_vset_id, ret);
216 		return ret;
217 	}
218 	return (data & FORCE_PWM_ENABLE) ?
219 				REGULATOR_MODE_FAST : REGULATOR_MODE_NORMAL;
220 }
221 
222 static const struct regulator_ops tps62360_dcdc_ops = {
223 	.get_voltage_sel	= tps62360_dcdc_get_voltage_sel,
224 	.set_voltage_sel	= tps62360_dcdc_set_voltage_sel,
225 	.list_voltage		= regulator_list_voltage_linear,
226 	.map_voltage		= regulator_map_voltage_linear,
227 	.set_voltage_time_sel	= regulator_set_voltage_time_sel,
228 	.set_mode		= tps62360_set_mode,
229 	.get_mode		= tps62360_get_mode,
230 };
231 
232 static int tps62360_init_dcdc(struct tps62360_chip *tps,
233 		struct tps62360_regulator_platform_data *pdata)
234 {
235 	int ret;
236 	unsigned int ramp_ctrl;
237 
238 	/* Initialize internal pull up/down control */
239 	if (tps->en_internal_pulldn)
240 		ret = regmap_write(tps->regmap, REG_CONTROL, 0xE0);
241 	else
242 		ret = regmap_write(tps->regmap, REG_CONTROL, 0x0);
243 	if (ret < 0) {
244 		dev_err(tps->dev,
245 			"%s(): register %d write failed with err %d\n",
246 			__func__, REG_CONTROL, ret);
247 		return ret;
248 	}
249 
250 	/* Reset output discharge path to reduce power consumption */
251 	ret = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), 0);
252 	if (ret < 0) {
253 		dev_err(tps->dev,
254 			"%s(): register %d update failed with err %d\n",
255 			__func__, REG_RAMPCTRL, ret);
256 		return ret;
257 	}
258 
259 	/* Get ramp value from ramp control register */
260 	ret = regmap_read(tps->regmap, REG_RAMPCTRL, &ramp_ctrl);
261 	if (ret < 0) {
262 		dev_err(tps->dev,
263 			"%s(): register %d read failed with err %d\n",
264 			__func__, REG_RAMPCTRL, ret);
265 		return ret;
266 	}
267 	ramp_ctrl = (ramp_ctrl >> 5) & 0x7;
268 
269 	/* ramp mV/us = 32/(2^ramp_ctrl) */
270 	tps->desc.ramp_delay = DIV_ROUND_UP(32000, BIT(ramp_ctrl));
271 	return ret;
272 }
273 
274 static const struct regmap_config tps62360_regmap_config = {
275 	.reg_bits		= 8,
276 	.val_bits		= 8,
277 	.max_register		= REG_CHIPID,
278 	.cache_type		= REGCACHE_RBTREE,
279 };
280 
281 static struct tps62360_regulator_platform_data *
282 	of_get_tps62360_platform_data(struct device *dev,
283 				      const struct regulator_desc *desc)
284 {
285 	struct tps62360_regulator_platform_data *pdata;
286 	struct device_node *np = dev->of_node;
287 
288 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
289 	if (!pdata)
290 		return NULL;
291 
292 	pdata->reg_init_data = of_get_regulator_init_data(dev, dev->of_node,
293 							  desc);
294 	if (!pdata->reg_init_data) {
295 		dev_err(dev, "Not able to get OF regulator init data\n");
296 		return NULL;
297 	}
298 
299 	pdata->vsel0_def_state = of_property_read_bool(np, "ti,vsel0-state-high");
300 	pdata->vsel1_def_state = of_property_read_bool(np, "ti,vsel1-state-high");
301 	pdata->en_internal_pulldn = of_property_read_bool(np, "ti,enable-pull-down");
302 	pdata->en_discharge = of_property_read_bool(np, "ti,enable-vout-discharge");
303 
304 	return pdata;
305 }
306 
307 #if defined(CONFIG_OF)
308 static const struct of_device_id tps62360_of_match[] = {
309 	 { .compatible = "ti,tps62360", .data = (void *)TPS62360},
310 	 { .compatible = "ti,tps62361", .data = (void *)TPS62361},
311 	 { .compatible = "ti,tps62362", .data = (void *)TPS62362},
312 	 { .compatible = "ti,tps62363", .data = (void *)TPS62363},
313 	{},
314 };
315 MODULE_DEVICE_TABLE(of, tps62360_of_match);
316 #endif
317 
318 static int tps62360_probe(struct i2c_client *client)
319 {
320 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
321 	struct regulator_config config = { };
322 	struct tps62360_regulator_platform_data *pdata;
323 	struct regulator_dev *rdev;
324 	struct tps62360_chip *tps;
325 	int ret;
326 	int i;
327 	int chip_id;
328 	int gpio_flags;
329 
330 	pdata = dev_get_platdata(&client->dev);
331 
332 	tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
333 	if (!tps)
334 		return -ENOMEM;
335 
336 	tps->desc.name = client->name;
337 	tps->desc.id = 0;
338 	tps->desc.ops = &tps62360_dcdc_ops;
339 	tps->desc.type = REGULATOR_VOLTAGE;
340 	tps->desc.owner = THIS_MODULE;
341 	tps->desc.uV_step = 10000;
342 
343 	if (client->dev.of_node) {
344 		const struct of_device_id *match;
345 		match = of_match_device(of_match_ptr(tps62360_of_match),
346 				&client->dev);
347 		if (!match) {
348 			dev_err(&client->dev, "Error: No device match found\n");
349 			return -ENODEV;
350 		}
351 		chip_id = (int)(long)match->data;
352 		if (!pdata)
353 			pdata = of_get_tps62360_platform_data(&client->dev,
354 							      &tps->desc);
355 	} else if (id) {
356 		chip_id = id->driver_data;
357 	} else {
358 		dev_err(&client->dev, "No device tree match or id table match found\n");
359 		return -ENODEV;
360 	}
361 
362 	if (!pdata) {
363 		dev_err(&client->dev, "%s(): Platform data not found\n",
364 						__func__);
365 		return -EIO;
366 	}
367 
368 	tps->en_discharge = pdata->en_discharge;
369 	tps->en_internal_pulldn = pdata->en_internal_pulldn;
370 	tps->dev = &client->dev;
371 
372 	switch (chip_id) {
373 	case TPS62360:
374 	case TPS62362:
375 		tps->desc.min_uV = TPS62360_BASE_VOLTAGE;
376 		tps->voltage_reg_mask = 0x3F;
377 		tps->desc.n_voltages = TPS62360_N_VOLTAGES;
378 		break;
379 	case TPS62361:
380 	case TPS62363:
381 		tps->desc.min_uV = TPS62361_BASE_VOLTAGE;
382 		tps->voltage_reg_mask = 0x7F;
383 		tps->desc.n_voltages = TPS62361_N_VOLTAGES;
384 		break;
385 	default:
386 		return -ENODEV;
387 	}
388 
389 	tps->regmap = devm_regmap_init_i2c(client, &tps62360_regmap_config);
390 	if (IS_ERR(tps->regmap)) {
391 		ret = PTR_ERR(tps->regmap);
392 		dev_err(&client->dev,
393 			"%s(): regmap allocation failed with err %d\n",
394 			__func__, ret);
395 		return ret;
396 	}
397 	i2c_set_clientdata(client, tps);
398 
399 	tps->curr_vset_id = (pdata->vsel1_def_state & 1) * 2 +
400 				(pdata->vsel0_def_state & 1);
401 	tps->lru_index[0] = tps->curr_vset_id;
402 	tps->valid_gpios = false;
403 
404 	gpio_flags = (pdata->vsel0_def_state) ?
405 			GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
406 	tps->vsel0_gpio = devm_gpiod_get_optional(&client->dev, "vsel0", gpio_flags);
407 	if (IS_ERR(tps->vsel0_gpio)) {
408 		dev_err(&client->dev,
409 			"%s(): Could not obtain vsel0 GPIO: %ld\n",
410 			__func__, PTR_ERR(tps->vsel0_gpio));
411 		return PTR_ERR(tps->vsel0_gpio);
412 	}
413 
414 	gpio_flags = (pdata->vsel1_def_state) ?
415 			GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
416 	tps->vsel1_gpio = devm_gpiod_get_optional(&client->dev, "vsel1", gpio_flags);
417 	if (IS_ERR(tps->vsel1_gpio)) {
418 		dev_err(&client->dev,
419 			"%s(): Could not obtain vsel1 GPIO: %ld\n",
420 			__func__, PTR_ERR(tps->vsel1_gpio));
421 		return PTR_ERR(tps->vsel1_gpio);
422 	}
423 
424 	if (tps->vsel0_gpio != NULL && tps->vsel1_gpio != NULL) {
425 		tps->valid_gpios = true;
426 
427 		/*
428 		 * Initialize the lru index with vset_reg id
429 		 * The index 0 will be most recently used and
430 		 * set with the tps->curr_vset_id */
431 		for (i = 0; i < 4; ++i)
432 			tps->lru_index[i] = i;
433 		tps->lru_index[0] = tps->curr_vset_id;
434 		tps->lru_index[tps->curr_vset_id] = 0;
435 	}
436 
437 	ret = tps62360_init_dcdc(tps, pdata);
438 	if (ret < 0) {
439 		dev_err(tps->dev, "%s(): Init failed with err = %d\n",
440 				__func__, ret);
441 		return ret;
442 	}
443 
444 	config.dev = &client->dev;
445 	config.init_data = pdata->reg_init_data;
446 	config.driver_data = tps;
447 	config.of_node = client->dev.of_node;
448 
449 	/* Register the regulators */
450 	rdev = devm_regulator_register(&client->dev, &tps->desc, &config);
451 	if (IS_ERR(rdev)) {
452 		dev_err(tps->dev,
453 			"%s(): regulator register failed with err %s\n",
454 			__func__, id->name);
455 		return PTR_ERR(rdev);
456 	}
457 
458 	tps->rdev = rdev;
459 	return 0;
460 }
461 
462 static void tps62360_shutdown(struct i2c_client *client)
463 {
464 	struct tps62360_chip *tps = i2c_get_clientdata(client);
465 	int st;
466 
467 	if (!tps->en_discharge)
468 		return;
469 
470 	/* Configure the output discharge path */
471 	st = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), BIT(2));
472 	if (st < 0)
473 		dev_err(tps->dev,
474 			"%s(): register %d update failed with err %d\n",
475 			__func__, REG_RAMPCTRL, st);
476 }
477 
478 static const struct i2c_device_id tps62360_id[] = {
479 	{.name = "tps62360", .driver_data = TPS62360},
480 	{.name = "tps62361", .driver_data = TPS62361},
481 	{.name = "tps62362", .driver_data = TPS62362},
482 	{.name = "tps62363", .driver_data = TPS62363},
483 	{},
484 };
485 
486 MODULE_DEVICE_TABLE(i2c, tps62360_id);
487 
488 static struct i2c_driver tps62360_i2c_driver = {
489 	.driver = {
490 		.name = "tps62360",
491 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
492 		.of_match_table = of_match_ptr(tps62360_of_match),
493 	},
494 	.probe_new = tps62360_probe,
495 	.shutdown = tps62360_shutdown,
496 	.id_table = tps62360_id,
497 };
498 
499 static int __init tps62360_init(void)
500 {
501 	return i2c_add_driver(&tps62360_i2c_driver);
502 }
503 subsys_initcall(tps62360_init);
504 
505 static void __exit tps62360_cleanup(void)
506 {
507 	i2c_del_driver(&tps62360_i2c_driver);
508 }
509 module_exit(tps62360_cleanup);
510 
511 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
512 MODULE_DESCRIPTION("TPS6236x voltage regulator driver");
513 MODULE_LICENSE("GPL v2");
514