tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Fuel gauge driver for Maxim 17042 / 8966 / 8997
3 * Note that Maxim 8966 and 8997 are mfd and this is its subdevice.
4 *
5 * Copyright (C) 2011 Samsung Electronics
6 * MyungJoo Ham <myungjoo.ham@samsung.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 * This driver is based on max17040_battery.c
23 */
24
25#include <linux/init.h>
26#include <linux/slab.h>
27#include <linux/i2c.h>
28#include <linux/mod_devicetable.h>
29#include <linux/power_supply.h>
30#include <linux/power/max17042_battery.h>
31
32enum max17042_register {
33 MAX17042_STATUS = 0x00,
34 MAX17042_VALRT_Th = 0x01,
35 MAX17042_TALRT_Th = 0x02,
36 MAX17042_SALRT_Th = 0x03,
37 MAX17042_AtRate = 0x04,
38 MAX17042_RepCap = 0x05,
39 MAX17042_RepSOC = 0x06,
40 MAX17042_Age = 0x07,
41 MAX17042_TEMP = 0x08,
42 MAX17042_VCELL = 0x09,
43 MAX17042_Current = 0x0A,
44 MAX17042_AvgCurrent = 0x0B,
45 MAX17042_Qresidual = 0x0C,
46 MAX17042_SOC = 0x0D,
47 MAX17042_AvSOC = 0x0E,
48 MAX17042_RemCap = 0x0F,
49 MAX17402_FullCAP = 0x10,
50 MAX17042_TTE = 0x11,
51 MAX17042_V_empty = 0x12,
52
53 MAX17042_RSLOW = 0x14,
54
55 MAX17042_AvgTA = 0x16,
56 MAX17042_Cycles = 0x17,
57 MAX17042_DesignCap = 0x18,
58 MAX17042_AvgVCELL = 0x19,
59 MAX17042_MinMaxTemp = 0x1A,
60 MAX17042_MinMaxVolt = 0x1B,
61 MAX17042_MinMaxCurr = 0x1C,
62 MAX17042_CONFIG = 0x1D,
63 MAX17042_ICHGTerm = 0x1E,
64 MAX17042_AvCap = 0x1F,
65 MAX17042_ManName = 0x20,
66 MAX17042_DevName = 0x21,
67 MAX17042_DevChem = 0x22,
68
69 MAX17042_TempNom = 0x24,
70 MAX17042_TempCold = 0x25,
71 MAX17042_TempHot = 0x26,
72 MAX17042_AIN = 0x27,
73 MAX17042_LearnCFG = 0x28,
74 MAX17042_SHFTCFG = 0x29,
75 MAX17042_RelaxCFG = 0x2A,
76 MAX17042_MiscCFG = 0x2B,
77 MAX17042_TGAIN = 0x2C,
78 MAx17042_TOFF = 0x2D,
79 MAX17042_CGAIN = 0x2E,
80 MAX17042_COFF = 0x2F,
81
82 MAX17042_Q_empty = 0x33,
83 MAX17042_T_empty = 0x34,
84
85 MAX17042_RCOMP0 = 0x38,
86 MAX17042_TempCo = 0x39,
87 MAX17042_Rx = 0x3A,
88 MAX17042_T_empty0 = 0x3B,
89 MAX17042_TaskPeriod = 0x3C,
90 MAX17042_FSTAT = 0x3D,
91
92 MAX17042_SHDNTIMER = 0x3F,
93
94 MAX17042_VFRemCap = 0x4A,
95
96 MAX17042_QH = 0x4D,
97 MAX17042_QL = 0x4E,
98};
99
100struct max17042_chip {
101 struct i2c_client *client;
102 struct power_supply battery;
103 struct max17042_platform_data *pdata;
104};
105
106static int max17042_write_reg(struct i2c_client *client, u8 reg, u16 value)
107{
108 int ret = i2c_smbus_write_word_data(client, reg, value);
109
110 if (ret < 0)
111 dev_err(&client->dev, "%s: err %d\n", __func__, ret);
112
113 return ret;
114}
115
116static int max17042_read_reg(struct i2c_client *client, u8 reg)
117{
118 int ret = i2c_smbus_read_word_data(client, reg);
119
120 if (ret < 0)
121 dev_err(&client->dev, "%s: err %d\n", __func__, ret);
122
123 return ret;
124}
125
126static enum power_supply_property max17042_battery_props[] = {
127 POWER_SUPPLY_PROP_VOLTAGE_NOW,
128 POWER_SUPPLY_PROP_VOLTAGE_AVG,
129 POWER_SUPPLY_PROP_CAPACITY,
130};
131
132static int max17042_get_property(struct power_supply *psy,
133 enum power_supply_property psp,
134 union power_supply_propval *val)
135{
136 struct max17042_chip *chip = container_of(psy,
137 struct max17042_chip, battery);
138
139 switch (psp) {
140 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
141 val->intval = max17042_read_reg(chip->client,
142 MAX17042_VCELL) * 83; /* 1000 / 12 = 83 */
143 break;
144 case POWER_SUPPLY_PROP_VOLTAGE_AVG:
145 val->intval = max17042_read_reg(chip->client,
146 MAX17042_AvgVCELL) * 83;
147 break;
148 case POWER_SUPPLY_PROP_CAPACITY:
149 val->intval = max17042_read_reg(chip->client,
150 MAX17042_SOC) / 256;
151 break;
152 default:
153 return -EINVAL;
154 }
155 return 0;
156}
157
158static int __devinit max17042_probe(struct i2c_client *client,
159 const struct i2c_device_id *id)
160{
161 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
162 struct max17042_chip *chip;
163 int ret;
164
165 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
166 return -EIO;
167
168 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
169 if (!chip)
170 return -ENOMEM;
171
172 chip->client = client;
173 chip->pdata = client->dev.platform_data;
174
175 i2c_set_clientdata(client, chip);
176
177 chip->battery.name = "max17042_battery";
178 chip->battery.type = POWER_SUPPLY_TYPE_BATTERY;
179 chip->battery.get_property = max17042_get_property;
180 chip->battery.properties = max17042_battery_props;
181 chip->battery.num_properties = ARRAY_SIZE(max17042_battery_props);
182
183 ret = power_supply_register(&client->dev, &chip->battery);
184 if (ret) {
185 dev_err(&client->dev, "failed: power supply register\n");
186 i2c_set_clientdata(client, NULL);
187 kfree(chip);
188 return ret;
189 }
190
191 if (!chip->pdata->enable_current_sense) {
192 max17042_write_reg(client, MAX17042_CGAIN, 0x0000);
193 max17042_write_reg(client, MAX17042_MiscCFG, 0x0003);
194 max17042_write_reg(client, MAX17042_LearnCFG, 0x0007);
195 }
196
197 return 0;
198}
199
200static int __devexit max17042_remove(struct i2c_client *client)
201{
202 struct max17042_chip *chip = i2c_get_clientdata(client);
203
204 power_supply_unregister(&chip->battery);
205 i2c_set_clientdata(client, NULL);
206 kfree(chip);
207 return 0;
208}
209
210static const struct i2c_device_id max17042_id[] = {
211 { "max17042", 0 },
212 { }
213};
214MODULE_DEVICE_TABLE(i2c, max17042_id);
215
216static struct i2c_driver max17042_i2c_driver = {
217 .driver = {
218 .name = "max17042",
219 },
220 .probe = max17042_probe,
221 .remove = __devexit_p(max17042_remove),
222 .id_table = max17042_id,
223};
224
225static int __init max17042_init(void)
226{
227 return i2c_add_driver(&max17042_i2c_driver);
228}
229module_init(max17042_init);
230
231static void __exit max17042_exit(void)
232{
233 i2c_del_driver(&max17042_i2c_driver);
234}
235module_exit(max17042_exit);
236
237MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
238MODULE_DESCRIPTION("MAX17042 Fuel Gauge");
239MODULE_LICENSE("GPL");