1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Battery charger driver for RT5033
4  *
5  * Copyright (C) 2014 Samsung Electronics, Co., Ltd.
6  * Author: Beomho Seo <beomho.seo@samsung.com>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/of_device.h>
11 #include <linux/platform_device.h>
12 #include <linux/power_supply.h>
13 #include <linux/regmap.h>
14 #include <linux/mfd/rt5033-private.h>
15 
16 struct rt5033_charger_data {
17 	unsigned int pre_uamp;
18 	unsigned int pre_uvolt;
19 	unsigned int const_uvolt;
20 	unsigned int eoc_uamp;
21 	unsigned int fast_uamp;
22 };
23 
24 struct rt5033_charger {
25 	struct device			*dev;
26 	struct regmap			*regmap;
27 	struct power_supply		*psy;
28 	struct rt5033_charger_data	*chg;
29 };
30 
31 static int rt5033_get_charger_state(struct rt5033_charger *charger)
32 {
33 	struct regmap *regmap = charger->regmap;
34 	unsigned int reg_data;
35 	int state;
36 
37 	if (!regmap)
38 		return POWER_SUPPLY_STATUS_UNKNOWN;
39 
40 	regmap_read(regmap, RT5033_REG_CHG_STAT, &reg_data);
41 
42 	switch (reg_data & RT5033_CHG_STAT_MASK) {
43 	case RT5033_CHG_STAT_DISCHARGING:
44 		state = POWER_SUPPLY_STATUS_DISCHARGING;
45 		break;
46 	case RT5033_CHG_STAT_CHARGING:
47 		state = POWER_SUPPLY_STATUS_CHARGING;
48 		break;
49 	case RT5033_CHG_STAT_FULL:
50 		state = POWER_SUPPLY_STATUS_FULL;
51 		break;
52 	case RT5033_CHG_STAT_NOT_CHARGING:
53 		state = POWER_SUPPLY_STATUS_NOT_CHARGING;
54 		break;
55 	default:
56 		state = POWER_SUPPLY_STATUS_UNKNOWN;
57 	}
58 
59 	return state;
60 }
61 
62 static int rt5033_get_charger_type(struct rt5033_charger *charger)
63 {
64 	struct regmap *regmap = charger->regmap;
65 	unsigned int reg_data;
66 	int state;
67 
68 	regmap_read(regmap, RT5033_REG_CHG_STAT, &reg_data);
69 
70 	switch (reg_data & RT5033_CHG_STAT_TYPE_MASK) {
71 	case RT5033_CHG_STAT_TYPE_FAST:
72 		state = POWER_SUPPLY_CHARGE_TYPE_FAST;
73 		break;
74 	case RT5033_CHG_STAT_TYPE_PRE:
75 		state = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
76 		break;
77 	default:
78 		state = POWER_SUPPLY_CHARGE_TYPE_NONE;
79 	}
80 
81 	return state;
82 }
83 
84 static int rt5033_get_charger_current_limit(struct rt5033_charger *charger)
85 {
86 	struct regmap *regmap = charger->regmap;
87 	unsigned int state, reg_data, data;
88 
89 	regmap_read(regmap, RT5033_REG_CHG_CTRL5, &reg_data);
90 
91 	state = (reg_data & RT5033_CHGCTRL5_ICHG_MASK)
92 		 >> RT5033_CHGCTRL5_ICHG_SHIFT;
93 
94 	data = RT5033_CHARGER_FAST_CURRENT_MIN +
95 		RT5033_CHARGER_FAST_CURRENT_STEP_NUM * state;
96 
97 	return data;
98 }
99 
100 static int rt5033_get_charger_const_voltage(struct rt5033_charger *charger)
101 {
102 	struct regmap *regmap = charger->regmap;
103 	unsigned int state, reg_data, data;
104 
105 	regmap_read(regmap, RT5033_REG_CHG_CTRL2, &reg_data);
106 
107 	state = (reg_data & RT5033_CHGCTRL2_CV_MASK)
108 		 >> RT5033_CHGCTRL2_CV_SHIFT;
109 
110 	data = RT5033_CHARGER_CONST_VOLTAGE_LIMIT_MIN +
111 		RT5033_CHARGER_CONST_VOLTAGE_STEP_NUM * state;
112 
113 	return data;
114 }
115 
116 static inline int rt5033_init_const_charge(struct rt5033_charger *charger)
117 {
118 	struct rt5033_charger_data *chg = charger->chg;
119 	int ret;
120 	unsigned int val;
121 	u8 reg_data;
122 
123 	/* Set constant voltage mode */
124 	if (chg->const_uvolt < RT5033_CHARGER_CONST_VOLTAGE_LIMIT_MIN ||
125 	    chg->const_uvolt > RT5033_CHARGER_CONST_VOLTAGE_LIMIT_MAX) {
126 		dev_err(charger->dev,
127 			"Value 'constant-charge-voltage-max-microvolt' out of range\n");
128 		return -EINVAL;
129 	}
130 
131 	if (chg->const_uvolt == RT5033_CHARGER_CONST_VOLTAGE_LIMIT_MIN)
132 		reg_data = 0x00;
133 	else if (chg->const_uvolt == RT5033_CHARGER_CONST_VOLTAGE_LIMIT_MAX)
134 		reg_data = RT5033_CV_MAX_VOLTAGE;
135 	else {
136 		val = chg->const_uvolt;
137 		val -= RT5033_CHARGER_CONST_VOLTAGE_LIMIT_MIN;
138 		val /= RT5033_CHARGER_CONST_VOLTAGE_STEP_NUM;
139 		reg_data = val;
140 	}
141 
142 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL2,
143 			RT5033_CHGCTRL2_CV_MASK,
144 			reg_data << RT5033_CHGCTRL2_CV_SHIFT);
145 	if (ret) {
146 		dev_err(charger->dev, "Failed regmap update\n");
147 		return -EINVAL;
148 	}
149 
150 	/* Set end of charge current */
151 	if (chg->eoc_uamp < RT5033_CHARGER_EOC_MIN ||
152 	    chg->eoc_uamp > RT5033_CHARGER_EOC_MAX) {
153 		dev_err(charger->dev,
154 			"Value 'charge-term-current-microamp' out of range\n");
155 		return -EINVAL;
156 	}
157 
158 	if (chg->eoc_uamp == RT5033_CHARGER_EOC_MIN)
159 		reg_data = 0x01;
160 	else if (chg->eoc_uamp == RT5033_CHARGER_EOC_MAX)
161 		reg_data = 0x07;
162 	else {
163 		val = chg->eoc_uamp;
164 		if (val < RT5033_CHARGER_EOC_REF) {
165 			val -= RT5033_CHARGER_EOC_MIN;
166 			val /= RT5033_CHARGER_EOC_STEP_NUM1;
167 			reg_data = 0x01 + val;
168 		} else if (val > RT5033_CHARGER_EOC_REF) {
169 			val -= RT5033_CHARGER_EOC_REF;
170 			val /= RT5033_CHARGER_EOC_STEP_NUM2;
171 			reg_data = 0x04 + val;
172 		} else {
173 			reg_data = 0x04;
174 		}
175 	}
176 
177 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL4,
178 			RT5033_CHGCTRL4_EOC_MASK, reg_data);
179 	if (ret) {
180 		dev_err(charger->dev, "Failed regmap update\n");
181 		return -EINVAL;
182 	}
183 
184 	return 0;
185 }
186 
187 static inline int rt5033_init_fast_charge(struct rt5033_charger *charger)
188 {
189 	struct rt5033_charger_data *chg = charger->chg;
190 	int ret;
191 	unsigned int val;
192 	u8 reg_data;
193 
194 	/* Set limit input current */
195 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL1,
196 			RT5033_CHGCTRL1_IAICR_MASK, RT5033_AICR_2000_MODE);
197 	if (ret) {
198 		dev_err(charger->dev, "Failed regmap update\n");
199 		return -EINVAL;
200 	}
201 
202 	/* Set fast-charge mode charging current */
203 	if (chg->fast_uamp < RT5033_CHARGER_FAST_CURRENT_MIN ||
204 	    chg->fast_uamp > RT5033_CHARGER_FAST_CURRENT_MAX) {
205 		dev_err(charger->dev,
206 			"Value 'constant-charge-current-max-microamp' out of range\n");
207 		return -EINVAL;
208 	}
209 
210 	if (chg->fast_uamp == RT5033_CHARGER_FAST_CURRENT_MIN)
211 		reg_data = 0x00;
212 	else if (chg->fast_uamp == RT5033_CHARGER_FAST_CURRENT_MAX)
213 		reg_data = RT5033_CHG_MAX_CURRENT;
214 	else {
215 		val = chg->fast_uamp;
216 		val -= RT5033_CHARGER_FAST_CURRENT_MIN;
217 		val /= RT5033_CHARGER_FAST_CURRENT_STEP_NUM;
218 		reg_data = val;
219 	}
220 
221 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL5,
222 			RT5033_CHGCTRL5_ICHG_MASK,
223 			reg_data << RT5033_CHGCTRL5_ICHG_SHIFT);
224 	if (ret) {
225 		dev_err(charger->dev, "Failed regmap update\n");
226 		return -EINVAL;
227 	}
228 
229 	return 0;
230 }
231 
232 static inline int rt5033_init_pre_charge(struct rt5033_charger *charger)
233 {
234 	struct rt5033_charger_data *chg = charger->chg;
235 	int ret;
236 	unsigned int val;
237 	u8 reg_data;
238 
239 	/* Set pre-charge threshold voltage */
240 	if (chg->pre_uvolt < RT5033_CHARGER_PRE_THRESHOLD_LIMIT_MIN ||
241 	    chg->pre_uvolt > RT5033_CHARGER_PRE_THRESHOLD_LIMIT_MAX) {
242 		dev_err(charger->dev,
243 			"Value 'precharge-upper-limit-microvolt' out of range\n");
244 		return -EINVAL;
245 	}
246 
247 	if (chg->pre_uvolt == RT5033_CHARGER_PRE_THRESHOLD_LIMIT_MIN)
248 		reg_data = 0x00;
249 	else if (chg->pre_uvolt == RT5033_CHARGER_PRE_THRESHOLD_LIMIT_MAX)
250 		reg_data = 0x0f;
251 	else {
252 		val = chg->pre_uvolt;
253 		val -= RT5033_CHARGER_PRE_THRESHOLD_LIMIT_MIN;
254 		val /= RT5033_CHARGER_PRE_THRESHOLD_STEP_NUM;
255 		reg_data = val;
256 	}
257 
258 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL5,
259 			RT5033_CHGCTRL5_VPREC_MASK, reg_data);
260 	if (ret) {
261 		dev_err(charger->dev, "Failed regmap update\n");
262 		return -EINVAL;
263 	}
264 
265 	/* Set pre-charge mode charging current */
266 	if (chg->pre_uamp < RT5033_CHARGER_PRE_CURRENT_LIMIT_MIN ||
267 	    chg->pre_uamp > RT5033_CHARGER_PRE_CURRENT_LIMIT_MAX) {
268 		dev_err(charger->dev,
269 			"Value 'precharge-current-microamp' out of range\n");
270 		return -EINVAL;
271 	}
272 
273 	if (chg->pre_uamp == RT5033_CHARGER_PRE_CURRENT_LIMIT_MIN)
274 		reg_data = 0x00;
275 	else if (chg->pre_uamp == RT5033_CHARGER_PRE_CURRENT_LIMIT_MAX)
276 		reg_data = RT5033_CHG_MAX_PRE_CURRENT;
277 	else {
278 		val = chg->pre_uamp;
279 		val -= RT5033_CHARGER_PRE_CURRENT_LIMIT_MIN;
280 		val /= RT5033_CHARGER_PRE_CURRENT_STEP_NUM;
281 		reg_data = val;
282 	}
283 
284 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL4,
285 			RT5033_CHGCTRL4_IPREC_MASK,
286 			reg_data << RT5033_CHGCTRL4_IPREC_SHIFT);
287 	if (ret) {
288 		dev_err(charger->dev, "Failed regmap update\n");
289 		return -EINVAL;
290 	}
291 
292 	return 0;
293 }
294 
295 static int rt5033_charger_reg_init(struct rt5033_charger *charger)
296 {
297 	int ret = 0;
298 
299 	/* Enable charging termination */
300 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL1,
301 			RT5033_CHGCTRL1_TE_EN_MASK, RT5033_TE_ENABLE);
302 	if (ret) {
303 		dev_err(charger->dev, "Failed to enable charging termination.\n");
304 		return -EINVAL;
305 	}
306 
307 	/*
308 	 * Disable minimum input voltage regulation (MIVR), this improves
309 	 * the charging performance.
310 	 */
311 	ret = regmap_update_bits(charger->regmap, RT5033_REG_CHG_CTRL4,
312 			RT5033_CHGCTRL4_MIVR_MASK, RT5033_CHARGER_MIVR_DISABLE);
313 	if (ret) {
314 		dev_err(charger->dev, "Failed to disable MIVR.\n");
315 		return -EINVAL;
316 	}
317 
318 	ret = rt5033_init_pre_charge(charger);
319 	if (ret)
320 		return ret;
321 
322 	ret = rt5033_init_fast_charge(charger);
323 	if (ret)
324 		return ret;
325 
326 	ret = rt5033_init_const_charge(charger);
327 	if (ret)
328 		return ret;
329 
330 	return 0;
331 }
332 
333 static enum power_supply_property rt5033_charger_props[] = {
334 	POWER_SUPPLY_PROP_STATUS,
335 	POWER_SUPPLY_PROP_CHARGE_TYPE,
336 	POWER_SUPPLY_PROP_CURRENT_MAX,
337 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
338 	POWER_SUPPLY_PROP_MODEL_NAME,
339 	POWER_SUPPLY_PROP_MANUFACTURER,
340 	POWER_SUPPLY_PROP_ONLINE,
341 };
342 
343 static int rt5033_charger_get_property(struct power_supply *psy,
344 			enum power_supply_property psp,
345 			union power_supply_propval *val)
346 {
347 	struct rt5033_charger *charger = power_supply_get_drvdata(psy);
348 
349 	switch (psp) {
350 	case POWER_SUPPLY_PROP_STATUS:
351 		val->intval = rt5033_get_charger_state(charger);
352 		break;
353 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
354 		val->intval = rt5033_get_charger_type(charger);
355 		break;
356 	case POWER_SUPPLY_PROP_CURRENT_MAX:
357 		val->intval = rt5033_get_charger_current_limit(charger);
358 		break;
359 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
360 		val->intval = rt5033_get_charger_const_voltage(charger);
361 		break;
362 	case POWER_SUPPLY_PROP_MODEL_NAME:
363 		val->strval = RT5033_CHARGER_MODEL;
364 		break;
365 	case POWER_SUPPLY_PROP_MANUFACTURER:
366 		val->strval = RT5033_MANUFACTURER;
367 		break;
368 	case POWER_SUPPLY_PROP_ONLINE:
369 		val->intval = (rt5033_get_charger_state(charger) ==
370 				POWER_SUPPLY_STATUS_CHARGING);
371 		break;
372 	default:
373 		return -EINVAL;
374 	}
375 
376 	return 0;
377 }
378 
379 static struct rt5033_charger_data *rt5033_charger_dt_init(
380 						struct rt5033_charger *charger)
381 {
382 	struct rt5033_charger_data *chg;
383 	struct power_supply_battery_info *info;
384 	int ret;
385 
386 	chg = devm_kzalloc(charger->dev, sizeof(*chg), GFP_KERNEL);
387 	if (!chg)
388 		return ERR_PTR(-ENOMEM);
389 
390 	ret = power_supply_get_battery_info(charger->psy, &info);
391 	if (ret)
392 		return ERR_PTR(dev_err_probe(charger->dev, -EINVAL,
393 			       "missing battery info\n"));
394 
395 	/* Assign data. Validity will be checked in the init functions. */
396 	chg->pre_uamp = info->precharge_current_ua;
397 	chg->fast_uamp = info->constant_charge_current_max_ua;
398 	chg->eoc_uamp = info->charge_term_current_ua;
399 	chg->pre_uvolt = info->precharge_voltage_max_uv;
400 	chg->const_uvolt = info->constant_charge_voltage_max_uv;
401 
402 	return chg;
403 }
404 
405 static const struct power_supply_desc rt5033_charger_desc = {
406 	.name = "rt5033-charger",
407 	.type = POWER_SUPPLY_TYPE_USB,
408 	.properties = rt5033_charger_props,
409 	.num_properties = ARRAY_SIZE(rt5033_charger_props),
410 	.get_property = rt5033_charger_get_property,
411 };
412 
413 static int rt5033_charger_probe(struct platform_device *pdev)
414 {
415 	struct rt5033_charger *charger;
416 	struct power_supply_config psy_cfg = {};
417 	int ret;
418 
419 	charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
420 	if (!charger)
421 		return -ENOMEM;
422 
423 	platform_set_drvdata(pdev, charger);
424 	charger->dev = &pdev->dev;
425 	charger->regmap = dev_get_regmap(pdev->dev.parent, NULL);
426 
427 	psy_cfg.of_node = pdev->dev.of_node;
428 	psy_cfg.drv_data = charger;
429 
430 	charger->psy = devm_power_supply_register(&pdev->dev,
431 						  &rt5033_charger_desc,
432 						  &psy_cfg);
433 	if (IS_ERR(charger->psy))
434 		return dev_err_probe(&pdev->dev, PTR_ERR(charger->psy),
435 				     "Failed to register power supply\n");
436 
437 	charger->chg = rt5033_charger_dt_init(charger);
438 	if (IS_ERR_OR_NULL(charger->chg))
439 		return PTR_ERR(charger->chg);
440 
441 	ret = rt5033_charger_reg_init(charger);
442 	if (ret)
443 		return ret;
444 
445 	return 0;
446 }
447 
448 static const struct platform_device_id rt5033_charger_id[] = {
449 	{ "rt5033-charger", },
450 	{ }
451 };
452 MODULE_DEVICE_TABLE(platform, rt5033_charger_id);
453 
454 static const struct of_device_id rt5033_charger_of_match[] = {
455 	{ .compatible = "richtek,rt5033-charger", },
456 	{ }
457 };
458 MODULE_DEVICE_TABLE(of, rt5033_charger_of_match);
459 
460 static struct platform_driver rt5033_charger_driver = {
461 	.driver = {
462 		.name = "rt5033-charger",
463 		.of_match_table = rt5033_charger_of_match,
464 	},
465 	.probe = rt5033_charger_probe,
466 	.id_table = rt5033_charger_id,
467 };
468 module_platform_driver(rt5033_charger_driver);
469 
470 MODULE_DESCRIPTION("Richtek RT5033 charger driver");
471 MODULE_AUTHOR("Beomho Seo <beomho.seo@samsung.com>");
472 MODULE_LICENSE("GPL v2");
473