xref: /linux/drivers/power/supply/mm8013.c (revision a06c3fad49a50d5d5eb078f93e70f4d3eca5d5a5)
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_FULL,
75 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
76 	POWER_SUPPLY_PROP_CHARGE_NOW,
77 	POWER_SUPPLY_PROP_CURRENT_MAX,
78 	POWER_SUPPLY_PROP_CURRENT_NOW,
79 	POWER_SUPPLY_PROP_CYCLE_COUNT,
80 	POWER_SUPPLY_PROP_HEALTH,
81 	POWER_SUPPLY_PROP_PRESENT,
82 	POWER_SUPPLY_PROP_STATUS,
83 	POWER_SUPPLY_PROP_TEMP,
84 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
85 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
86 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
87 };
88 
89 static int mm8013_get_property(struct power_supply *psy,
90 			       enum power_supply_property psp,
91 			       union power_supply_propval *val)
92 {
93 	struct mm8013_chip *chip = psy->drv_data;
94 	int ret = 0;
95 	u32 regval;
96 
97 	switch (psp) {
98 	case POWER_SUPPLY_PROP_CAPACITY:
99 		ret = regmap_read(chip->regmap, REG_STATE_OF_CHARGE, &regval);
100 		if (ret < 0)
101 			return ret;
102 
103 		val->intval = regval;
104 		break;
105 	case POWER_SUPPLY_PROP_CHARGE_FULL:
106 		ret = regmap_read(chip->regmap, REG_FULL_CHARGE_CAPACITY, &regval);
107 		if (ret < 0)
108 			return ret;
109 
110 		val->intval = 1000 * regval;
111 		break;
112 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
113 		ret = regmap_read(chip->regmap, REG_DESIGN_CAPACITY, &regval);
114 		if (ret < 0)
115 			return ret;
116 
117 		val->intval = 1000 * regval;
118 		break;
119 	case POWER_SUPPLY_PROP_CHARGE_NOW:
120 		ret = regmap_read(chip->regmap, REG_NOMINAL_CHARGE_CAPACITY, &regval);
121 		if (ret < 0)
122 			return ret;
123 
124 		val->intval = 1000 * regval;
125 		break;
126 	case POWER_SUPPLY_PROP_CURRENT_MAX:
127 		ret = regmap_read(chip->regmap, REG_MAX_LOAD_CURRENT, &regval);
128 		if (ret < 0)
129 			return ret;
130 
131 		val->intval = -1000 * (s16)regval;
132 		break;
133 	case POWER_SUPPLY_PROP_CURRENT_NOW:
134 		ret = regmap_read(chip->regmap, REG_AVERAGE_CURRENT, &regval);
135 		if (ret < 0)
136 			return ret;
137 
138 		val->intval = -1000 * (s16)regval;
139 		break;
140 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
141 		ret = regmap_read(chip->regmap, REG_CYCLE_COUNT, &regval);
142 		if (ret < 0)
143 			return ret;
144 
145 		val->intval = regval;
146 		break;
147 	case POWER_SUPPLY_PROP_HEALTH:
148 		ret = regmap_read(chip->regmap, REG_FLAGS, &regval);
149 		if (ret < 0)
150 			return ret;
151 
152 		if (regval & MM8013_FLAG_UT)
153 			val->intval = POWER_SUPPLY_HEALTH_COLD;
154 		else if (regval & (MM8013_FLAG_ODC | MM8013_FLAG_OCC))
155 			val->intval = POWER_SUPPLY_HEALTH_OVERCURRENT;
156 		else if (regval & (MM8013_FLAG_BATLOW))
157 			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
158 		else if (regval & MM8013_FLAG_BATHI)
159 			val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
160 		else if (regval & (MM8013_FLAG_OT | MM8013_FLAG_OTD | MM8013_FLAG_OTC))
161 			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
162 		else
163 			val->intval = POWER_SUPPLY_HEALTH_GOOD;
164 		break;
165 	case POWER_SUPPLY_PROP_PRESENT:
166 		ret = regmap_read(chip->regmap, REG_TEMPERATURE, &regval);
167 		if (ret < 0)
168 			return ret;
169 
170 		val->intval = ((s16)regval > 0);
171 		break;
172 	case POWER_SUPPLY_PROP_STATUS:
173 		ret = regmap_read(chip->regmap, REG_FLAGS, &regval);
174 		if (ret < 0)
175 			return ret;
176 
177 		if (regval & MM8013_FLAG_DSG)
178 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
179 		else if (regval & MM8013_FLAG_CHG_INH)
180 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
181 		else if (regval & MM8013_FLAG_CHG)
182 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
183 		else if (regval & MM8013_FLAG_FC)
184 			val->intval = POWER_SUPPLY_STATUS_FULL;
185 		else
186 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
187 		break;
188 	case POWER_SUPPLY_PROP_TEMP:
189 		ret = regmap_read(chip->regmap, REG_TEMPERATURE, &regval);
190 		if (ret < 0)
191 			return ret;
192 
193 		val->intval = DECIKELVIN_TO_DECIDEGC(regval);
194 		break;
195 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
196 		ret = regmap_read(chip->regmap, REG_AVERAGE_TIME_TO_EMPTY, &regval);
197 		if (ret < 0)
198 			return ret;
199 
200 		/* The estimation is not yet ready */
201 		if (regval == U16_MAX)
202 			return -ENODATA;
203 
204 		val->intval = regval;
205 		break;
206 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
207 		ret = regmap_read(chip->regmap, REG_AVERAGE_TIME_TO_FULL, &regval);
208 		if (ret < 0)
209 			return ret;
210 
211 		/* The estimation is not yet ready */
212 		if (regval == U16_MAX)
213 			return -ENODATA;
214 
215 		val->intval = regval;
216 		break;
217 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
218 		ret = regmap_read(chip->regmap, REG_VOLTAGE, &regval);
219 		if (ret < 0)
220 			return ret;
221 
222 		val->intval = 1000 * regval;
223 		break;
224 	default:
225 		return -EINVAL;
226 	}
227 
228 	return 0;
229 }
230 
231 static const struct power_supply_desc mm8013_desc = {
232 	.name			= "mm8013",
233 	.type			= POWER_SUPPLY_TYPE_BATTERY,
234 	.properties		= mm8013_battery_props,
235 	.num_properties		= ARRAY_SIZE(mm8013_battery_props),
236 	.get_property		= mm8013_get_property,
237 };
238 
239 static const struct regmap_config mm8013_regmap_config = {
240 	.reg_bits = 8,
241 	.val_bits = 16,
242 	.max_register = 0x68,
243 	.use_single_read = true,
244 	.use_single_write = true,
245 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
246 };
247 
248 static int mm8013_probe(struct i2c_client *client)
249 {
250 	struct power_supply_config psy_cfg = {};
251 	struct device *dev = &client->dev;
252 	struct power_supply *psy;
253 	struct mm8013_chip *chip;
254 	int ret = 0;
255 
256 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
257 		return dev_err_probe(dev, -EIO,
258 				     "I2C_FUNC_SMBUS_WORD_DATA not supported\n");
259 
260 	chip = devm_kzalloc(dev, sizeof(struct mm8013_chip), GFP_KERNEL);
261 	if (!chip)
262 		return -ENOMEM;
263 
264 	chip->client = client;
265 
266 	chip->regmap = devm_regmap_init_i2c(client, &mm8013_regmap_config);
267 	if (IS_ERR(chip->regmap)) {
268 		ret = PTR_ERR(chip->regmap);
269 		return dev_err_probe(dev, ret, "Couldn't initialize regmap\n");
270 	}
271 
272 	ret = mm8013_checkdevice(chip);
273 	if (ret)
274 		return dev_err_probe(dev, ret, "MM8013 not found\n");
275 
276 	psy_cfg.drv_data = chip;
277 	psy_cfg.of_node = dev->of_node;
278 
279 	psy = devm_power_supply_register(dev, &mm8013_desc, &psy_cfg);
280 	if (IS_ERR(psy))
281 		return PTR_ERR(psy);
282 
283 	return 0;
284 }
285 
286 static const struct i2c_device_id mm8013_id_table[] = {
287 	{ "mm8013" },
288 	{}
289 };
290 MODULE_DEVICE_TABLE(i2c, mm8013_id_table);
291 
292 static const struct of_device_id mm8013_match_table[] = {
293 	{ .compatible = "mitsumi,mm8013" },
294 	{}
295 };
296 
297 static struct i2c_driver mm8013_i2c_driver = {
298 	.probe = mm8013_probe,
299 	.id_table = mm8013_id_table,
300 	.driver = {
301 		.name = "mm8013",
302 		.of_match_table = mm8013_match_table,
303 	},
304 };
305 module_i2c_driver(mm8013_i2c_driver);
306 
307 MODULE_DESCRIPTION("MM8013 fuel gauge driver");
308 MODULE_LICENSE("GPL");
309