xref: /linux/drivers/power/supply/mm8013.c (revision 73aea586d6c58f55799f6130e19321ff7b574c3d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2016-2019 The Linux Foundation. All rights reserved.
4  * Copyright (c) 2023, Linaro Limited
5  */
6 #include <linux/delay.h>
7 #include <linux/i2c.h>
8 #include <linux/power_supply.h>
9 #include <linux/regmap.h>
10 
11 #define REG_BATID			0x00 /* This one is very unclear */
12  #define BATID_101			0x0101 /* 107kOhm */
13  #define BATID_102			0x0102 /* 10kOhm */
14 #define REG_TEMPERATURE			0x06
15 #define REG_VOLTAGE			0x08
16 #define REG_FLAGS			0x0a
17  #define MM8013_FLAG_OTC		BIT(15)
18  #define MM8013_FLAG_OTD		BIT(14)
19  #define MM8013_FLAG_BATHI		BIT(13)
20  #define MM8013_FLAG_BATLOW		BIT(12)
21  #define MM8013_FLAG_CHG_INH		BIT(11)
22  #define MM8013_FLAG_FC			BIT(9)
23  #define MM8013_FLAG_CHG		BIT(8)
24  #define MM8013_FLAG_OCC		BIT(6)
25  #define MM8013_FLAG_ODC		BIT(5)
26  #define MM8013_FLAG_OT			BIT(4)
27  #define MM8013_FLAG_UT			BIT(3)
28  #define MM8013_FLAG_DSG		BIT(0)
29 #define REG_FULL_CHARGE_CAPACITY	0x0e
30 #define REG_NOMINAL_CHARGE_CAPACITY	0x0c
31 #define REG_AVERAGE_CURRENT		0x14
32 #define REG_AVERAGE_TIME_TO_EMPTY	0x16
33 #define REG_AVERAGE_TIME_TO_FULL	0x18
34 #define REG_MAX_LOAD_CURRENT		0x1e
35 #define REG_CYCLE_COUNT			0x2a
36 #define REG_STATE_OF_CHARGE		0x2c
37 #define REG_DESIGN_CAPACITY		0x3c
38 /* TODO: 0x62-0x68 seem to contain 'MM8013C' in a length-prefixed, non-terminated string */
39 
40 #define DECIKELVIN_TO_DECIDEGC(t)	(t - 2731)
41 
42 struct mm8013_chip {
43 	struct i2c_client *client;
44 	struct regmap *regmap;
45 };
46 
47 static int mm8013_checkdevice(struct mm8013_chip *chip)
48 {
49 	int battery_id, ret;
50 	u32 val;
51 
52 	ret = regmap_write(chip->regmap, REG_BATID, 0x0008);
53 	if (ret < 0)
54 		return ret;
55 
56 	ret = regmap_read(chip->regmap, REG_BATID, &val);
57 	if (ret < 0)
58 		return ret;
59 
60 	if (val == BATID_102)
61 		battery_id = 2;
62 	else if (val == BATID_101)
63 		battery_id = 1;
64 	else
65 		return -EINVAL;
66 
67 	dev_dbg(&chip->client->dev, "battery_id: %d\n", battery_id);
68 
69 	return 0;
70 }
71 
72 static enum power_supply_property mm8013_battery_props[] = {
73 	POWER_SUPPLY_PROP_CAPACITY,
74 	POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR,
75 	POWER_SUPPLY_PROP_CHARGE_FULL,
76 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
77 	POWER_SUPPLY_PROP_CHARGE_NOW,
78 	POWER_SUPPLY_PROP_CURRENT_MAX,
79 	POWER_SUPPLY_PROP_CURRENT_NOW,
80 	POWER_SUPPLY_PROP_CYCLE_COUNT,
81 	POWER_SUPPLY_PROP_HEALTH,
82 	POWER_SUPPLY_PROP_PRESENT,
83 	POWER_SUPPLY_PROP_STATUS,
84 	POWER_SUPPLY_PROP_TEMP,
85 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
86 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
87 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
88 };
89 
90 static int mm8013_get_property(struct power_supply *psy,
91 			       enum power_supply_property psp,
92 			       union power_supply_propval *val)
93 {
94 	struct mm8013_chip *chip = psy->drv_data;
95 	int ret = 0;
96 	u32 regval;
97 
98 	switch (psp) {
99 	case POWER_SUPPLY_PROP_CAPACITY:
100 		ret = regmap_read(chip->regmap, REG_STATE_OF_CHARGE, &regval);
101 		if (ret < 0)
102 			return ret;
103 
104 		val->intval = regval;
105 		break;
106 	case POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR:
107 		ret = regmap_read(chip->regmap, REG_FLAGS, &regval);
108 		if (ret < 0)
109 			return ret;
110 
111 		if (regval & MM8013_FLAG_CHG_INH)
112 			val->intval = POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE;
113 		else
114 			val->intval = POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO;
115 		break;
116 	case POWER_SUPPLY_PROP_CHARGE_FULL:
117 		ret = regmap_read(chip->regmap, REG_FULL_CHARGE_CAPACITY, &regval);
118 		if (ret < 0)
119 			return ret;
120 
121 		val->intval = 1000 * regval;
122 		break;
123 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
124 		ret = regmap_read(chip->regmap, REG_DESIGN_CAPACITY, &regval);
125 		if (ret < 0)
126 			return ret;
127 
128 		val->intval = 1000 * regval;
129 		break;
130 	case POWER_SUPPLY_PROP_CHARGE_NOW:
131 		ret = regmap_read(chip->regmap, REG_NOMINAL_CHARGE_CAPACITY, &regval);
132 		if (ret < 0)
133 			return ret;
134 
135 		val->intval = 1000 * regval;
136 		break;
137 	case POWER_SUPPLY_PROP_CURRENT_MAX:
138 		ret = regmap_read(chip->regmap, REG_MAX_LOAD_CURRENT, &regval);
139 		if (ret < 0)
140 			return ret;
141 
142 		val->intval = -1000 * (s16)regval;
143 		break;
144 	case POWER_SUPPLY_PROP_CURRENT_NOW:
145 		ret = regmap_read(chip->regmap, REG_AVERAGE_CURRENT, &regval);
146 		if (ret < 0)
147 			return ret;
148 
149 		val->intval = -1000 * (s16)regval;
150 		break;
151 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
152 		ret = regmap_read(chip->regmap, REG_CYCLE_COUNT, &regval);
153 		if (ret < 0)
154 			return ret;
155 
156 		val->intval = regval;
157 		break;
158 	case POWER_SUPPLY_PROP_HEALTH:
159 		ret = regmap_read(chip->regmap, REG_FLAGS, &regval);
160 		if (ret < 0)
161 			return ret;
162 
163 		if (regval & MM8013_FLAG_UT)
164 			val->intval = POWER_SUPPLY_HEALTH_COLD;
165 		else if (regval & (MM8013_FLAG_ODC | MM8013_FLAG_OCC))
166 			val->intval = POWER_SUPPLY_HEALTH_OVERCURRENT;
167 		else if (regval & (MM8013_FLAG_BATLOW))
168 			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
169 		else if (regval & MM8013_FLAG_BATHI)
170 			val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
171 		else if (regval & (MM8013_FLAG_OT | MM8013_FLAG_OTD | MM8013_FLAG_OTC))
172 			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
173 		else
174 			val->intval = POWER_SUPPLY_HEALTH_GOOD;
175 		break;
176 	case POWER_SUPPLY_PROP_PRESENT:
177 		ret = regmap_read(chip->regmap, REG_TEMPERATURE, &regval);
178 		if (ret < 0)
179 			return ret;
180 
181 		val->intval = ((s16)regval > 0);
182 		break;
183 	case POWER_SUPPLY_PROP_STATUS:
184 		ret = regmap_read(chip->regmap, REG_FLAGS, &regval);
185 		if (ret < 0)
186 			return ret;
187 
188 		if (regval & MM8013_FLAG_DSG)
189 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
190 		else if (regval & MM8013_FLAG_CHG)
191 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
192 		else if (regval & MM8013_FLAG_FC)
193 			val->intval = POWER_SUPPLY_STATUS_FULL;
194 		else
195 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
196 		break;
197 	case POWER_SUPPLY_PROP_TEMP:
198 		ret = regmap_read(chip->regmap, REG_TEMPERATURE, &regval);
199 		if (ret < 0)
200 			return ret;
201 
202 		val->intval = DECIKELVIN_TO_DECIDEGC(regval);
203 		break;
204 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
205 		ret = regmap_read(chip->regmap, REG_AVERAGE_TIME_TO_EMPTY, &regval);
206 		if (ret < 0)
207 			return ret;
208 
209 		/* The estimation is not yet ready */
210 		if (regval == U16_MAX)
211 			return -ENODATA;
212 
213 		val->intval = regval;
214 		break;
215 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
216 		ret = regmap_read(chip->regmap, REG_AVERAGE_TIME_TO_FULL, &regval);
217 		if (ret < 0)
218 			return ret;
219 
220 		/* The estimation is not yet ready */
221 		if (regval == U16_MAX)
222 			return -ENODATA;
223 
224 		val->intval = regval;
225 		break;
226 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
227 		ret = regmap_read(chip->regmap, REG_VOLTAGE, &regval);
228 		if (ret < 0)
229 			return ret;
230 
231 		val->intval = 1000 * regval;
232 		break;
233 	default:
234 		return -EINVAL;
235 	}
236 
237 	return 0;
238 }
239 
240 static const struct power_supply_desc mm8013_desc = {
241 	.name			= "mm8013",
242 	.type			= POWER_SUPPLY_TYPE_BATTERY,
243 	.properties		= mm8013_battery_props,
244 	.num_properties		= ARRAY_SIZE(mm8013_battery_props),
245 	.get_property		= mm8013_get_property,
246 };
247 
248 static const struct regmap_config mm8013_regmap_config = {
249 	.reg_bits = 8,
250 	.val_bits = 16,
251 	.max_register = 0x68,
252 	.use_single_read = true,
253 	.use_single_write = true,
254 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
255 };
256 
257 static int mm8013_probe(struct i2c_client *client)
258 {
259 	struct power_supply_config psy_cfg = {};
260 	struct device *dev = &client->dev;
261 	struct power_supply *psy;
262 	struct mm8013_chip *chip;
263 	int ret = 0;
264 
265 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
266 		return dev_err_probe(dev, -EIO,
267 				     "I2C_FUNC_SMBUS_WORD_DATA not supported\n");
268 
269 	chip = devm_kzalloc(dev, sizeof(struct mm8013_chip), GFP_KERNEL);
270 	if (!chip)
271 		return -ENOMEM;
272 
273 	chip->client = client;
274 
275 	chip->regmap = devm_regmap_init_i2c(client, &mm8013_regmap_config);
276 	if (IS_ERR(chip->regmap)) {
277 		ret = PTR_ERR(chip->regmap);
278 		return dev_err_probe(dev, ret, "Couldn't initialize regmap\n");
279 	}
280 
281 	ret = mm8013_checkdevice(chip);
282 	if (ret)
283 		return dev_err_probe(dev, ret, "MM8013 not found\n");
284 
285 	psy_cfg.drv_data = chip;
286 	psy_cfg.of_node = dev->of_node;
287 
288 	psy = devm_power_supply_register(dev, &mm8013_desc, &psy_cfg);
289 	if (IS_ERR(psy))
290 		return PTR_ERR(psy);
291 
292 	return 0;
293 }
294 
295 static const struct i2c_device_id mm8013_id_table[] = {
296 	{ "mm8013", 0 },
297 	{}
298 };
299 MODULE_DEVICE_TABLE(i2c, mm8013_id_table);
300 
301 static const struct of_device_id mm8013_match_table[] = {
302 	{ .compatible = "mitsumi,mm8013" },
303 	{}
304 };
305 
306 static struct i2c_driver mm8013_i2c_driver = {
307 	.probe = mm8013_probe,
308 	.id_table = mm8013_id_table,
309 	.driver = {
310 		.name = "mm8013",
311 		.of_match_table = mm8013_match_table,
312 	},
313 };
314 module_i2c_driver(mm8013_i2c_driver);
315 
316 MODULE_DESCRIPTION("MM8013 fuel gauge driver");
317 MODULE_LICENSE("GPL");
318