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
mm8013_checkdevice(struct mm8013_chip * chip)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
mm8013_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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, ®val);
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
mm8013_probe(struct i2c_client * client)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