Make vfio MSI interrupt be non-threaded.
[kvmfornfv.git] / kernel / drivers / power / twl4030_madc_battery.c
1 /*
2  * Dumb driver for LiIon batteries using TWL4030 madc.
3  *
4  * Copyright 2013 Golden Delicious Computers
5  * Lukas Märdian <lukas@goldelico.com>
6  *
7  * Based on dumb driver for gta01 battery
8  * Copyright 2009 Openmoko, Inc
9  * Balaji Rao <balajirrao@openmoko.org>
10  */
11
12 #include <linux/module.h>
13 #include <linux/param.h>
14 #include <linux/delay.h>
15 #include <linux/workqueue.h>
16 #include <linux/platform_device.h>
17 #include <linux/power_supply.h>
18 #include <linux/slab.h>
19 #include <linux/sort.h>
20 #include <linux/i2c/twl4030-madc.h>
21 #include <linux/power/twl4030_madc_battery.h>
22 #include <linux/iio/consumer.h>
23
24 struct twl4030_madc_battery {
25         struct power_supply *psy;
26         struct twl4030_madc_bat_platform_data *pdata;
27         struct iio_channel *channel_temp;
28         struct iio_channel *channel_ichg;
29         struct iio_channel *channel_vbat;
30 };
31
32 static enum power_supply_property twl4030_madc_bat_props[] = {
33         POWER_SUPPLY_PROP_PRESENT,
34         POWER_SUPPLY_PROP_STATUS,
35         POWER_SUPPLY_PROP_TECHNOLOGY,
36         POWER_SUPPLY_PROP_VOLTAGE_NOW,
37         POWER_SUPPLY_PROP_CURRENT_NOW,
38         POWER_SUPPLY_PROP_CAPACITY,
39         POWER_SUPPLY_PROP_CHARGE_FULL,
40         POWER_SUPPLY_PROP_CHARGE_NOW,
41         POWER_SUPPLY_PROP_TEMP,
42         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
43 };
44
45 static int madc_read(struct iio_channel *channel)
46 {
47         int val, err;
48         err = iio_read_channel_processed(channel, &val);
49         if (err < 0)
50                 return err;
51
52         return val;
53 }
54
55 static int twl4030_madc_bat_get_charging_status(struct twl4030_madc_battery *bt)
56 {
57         return (madc_read(bt->channel_ichg) > 0) ? 1 : 0;
58 }
59
60 static int twl4030_madc_bat_get_voltage(struct twl4030_madc_battery *bt)
61 {
62         return madc_read(bt->channel_vbat);
63 }
64
65 static int twl4030_madc_bat_get_current(struct twl4030_madc_battery *bt)
66 {
67         return madc_read(bt->channel_ichg) * 1000;
68 }
69
70 static int twl4030_madc_bat_get_temp(struct twl4030_madc_battery *bt)
71 {
72         return madc_read(bt->channel_temp) * 10;
73 }
74
75 static int twl4030_madc_bat_voltscale(struct twl4030_madc_battery *bat,
76                                         int volt)
77 {
78         struct twl4030_madc_bat_calibration *calibration;
79         int i, res = 0;
80
81         /* choose charging curve */
82         if (twl4030_madc_bat_get_charging_status(bat))
83                 calibration = bat->pdata->charging;
84         else
85                 calibration = bat->pdata->discharging;
86
87         if (volt > calibration[0].voltage) {
88                 res = calibration[0].level;
89         } else {
90                 for (i = 0; calibration[i+1].voltage >= 0; i++) {
91                         if (volt <= calibration[i].voltage &&
92                                         volt >= calibration[i+1].voltage) {
93                                 /* interval found - interpolate within range */
94                                 res = calibration[i].level -
95                                         ((calibration[i].voltage - volt) *
96                                         (calibration[i].level -
97                                         calibration[i+1].level)) /
98                                         (calibration[i].voltage -
99                                         calibration[i+1].voltage);
100                                 break;
101                         }
102                 }
103         }
104         return res;
105 }
106
107 static int twl4030_madc_bat_get_property(struct power_supply *psy,
108                                         enum power_supply_property psp,
109                                         union power_supply_propval *val)
110 {
111         struct twl4030_madc_battery *bat = power_supply_get_drvdata(psy);
112
113         switch (psp) {
114         case POWER_SUPPLY_PROP_STATUS:
115                 if (twl4030_madc_bat_voltscale(bat,
116                                 twl4030_madc_bat_get_voltage(bat)) > 95)
117                         val->intval = POWER_SUPPLY_STATUS_FULL;
118                 else {
119                         if (twl4030_madc_bat_get_charging_status(bat))
120                                 val->intval = POWER_SUPPLY_STATUS_CHARGING;
121                         else
122                                 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
123                 }
124                 break;
125         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
126                 val->intval = twl4030_madc_bat_get_voltage(bat) * 1000;
127                 break;
128         case POWER_SUPPLY_PROP_TECHNOLOGY:
129                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
130                 break;
131         case POWER_SUPPLY_PROP_CURRENT_NOW:
132                 val->intval = twl4030_madc_bat_get_current(bat);
133                 break;
134         case POWER_SUPPLY_PROP_PRESENT:
135                 /* assume battery is always present */
136                 val->intval = 1;
137                 break;
138         case POWER_SUPPLY_PROP_CHARGE_NOW: {
139                         int percent = twl4030_madc_bat_voltscale(bat,
140                                         twl4030_madc_bat_get_voltage(bat));
141                         val->intval = (percent * bat->pdata->capacity) / 100;
142                         break;
143                 }
144         case POWER_SUPPLY_PROP_CAPACITY:
145                 val->intval = twl4030_madc_bat_voltscale(bat,
146                                         twl4030_madc_bat_get_voltage(bat));
147                 break;
148         case POWER_SUPPLY_PROP_CHARGE_FULL:
149                 val->intval = bat->pdata->capacity;
150                 break;
151         case POWER_SUPPLY_PROP_TEMP:
152                 val->intval = twl4030_madc_bat_get_temp(bat);
153                 break;
154         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: {
155                         int percent = twl4030_madc_bat_voltscale(bat,
156                                         twl4030_madc_bat_get_voltage(bat));
157                         /* in mAh */
158                         int chg = (percent * (bat->pdata->capacity/1000))/100;
159
160                         /* assume discharge with 400 mA (ca. 1.5W) */
161                         val->intval = (3600l * chg) / 400;
162                         break;
163                 }
164         default:
165                 return -EINVAL;
166         }
167
168         return 0;
169 }
170
171 static void twl4030_madc_bat_ext_changed(struct power_supply *psy)
172 {
173         power_supply_changed(psy);
174 }
175
176 static const struct power_supply_desc twl4030_madc_bat_desc = {
177         .name                   = "twl4030_battery",
178         .type                   = POWER_SUPPLY_TYPE_BATTERY,
179         .properties             = twl4030_madc_bat_props,
180         .num_properties         = ARRAY_SIZE(twl4030_madc_bat_props),
181         .get_property           = twl4030_madc_bat_get_property,
182         .external_power_changed = twl4030_madc_bat_ext_changed,
183
184 };
185
186 static int twl4030_cmp(const void *a, const void *b)
187 {
188         return ((struct twl4030_madc_bat_calibration *)b)->voltage -
189                 ((struct twl4030_madc_bat_calibration *)a)->voltage;
190 }
191
192 static int twl4030_madc_battery_probe(struct platform_device *pdev)
193 {
194         struct twl4030_madc_battery *twl4030_madc_bat;
195         struct twl4030_madc_bat_platform_data *pdata = pdev->dev.platform_data;
196         struct power_supply_config psy_cfg = {};
197         int ret = 0;
198
199         twl4030_madc_bat = devm_kzalloc(&pdev->dev, sizeof(*twl4030_madc_bat),
200                                 GFP_KERNEL);
201         if (!twl4030_madc_bat)
202                 return -ENOMEM;
203
204         twl4030_madc_bat->channel_temp = iio_channel_get(&pdev->dev, "temp");
205         if (IS_ERR(twl4030_madc_bat->channel_temp)) {
206                 ret = PTR_ERR(twl4030_madc_bat->channel_temp);
207                 goto err;
208         }
209
210         twl4030_madc_bat->channel_ichg = iio_channel_get(&pdev->dev, "ichg");
211         if (IS_ERR(twl4030_madc_bat->channel_ichg)) {
212                 ret = PTR_ERR(twl4030_madc_bat->channel_ichg);
213                 goto err_temp;
214         }
215
216         twl4030_madc_bat->channel_vbat = iio_channel_get(&pdev->dev, "vbat");
217         if (IS_ERR(twl4030_madc_bat->channel_vbat)) {
218                 ret = PTR_ERR(twl4030_madc_bat->channel_vbat);
219                 goto err_ichg;
220         }
221
222         /* sort charging and discharging calibration data */
223         sort(pdata->charging, pdata->charging_size,
224                 sizeof(struct twl4030_madc_bat_calibration),
225                 twl4030_cmp, NULL);
226         sort(pdata->discharging, pdata->discharging_size,
227                 sizeof(struct twl4030_madc_bat_calibration),
228                 twl4030_cmp, NULL);
229
230         twl4030_madc_bat->pdata = pdata;
231         platform_set_drvdata(pdev, twl4030_madc_bat);
232         psy_cfg.drv_data = twl4030_madc_bat;
233         twl4030_madc_bat->psy = power_supply_register(&pdev->dev,
234                                                       &twl4030_madc_bat_desc,
235                                                       &psy_cfg);
236         if (IS_ERR(twl4030_madc_bat->psy)) {
237                 ret = PTR_ERR(twl4030_madc_bat->psy);
238                 goto err_vbat;
239         }
240
241         return 0;
242
243 err_vbat:
244         iio_channel_release(twl4030_madc_bat->channel_vbat);
245 err_ichg:
246         iio_channel_release(twl4030_madc_bat->channel_ichg);
247 err_temp:
248         iio_channel_release(twl4030_madc_bat->channel_temp);
249 err:
250         return ret;
251 }
252
253 static int twl4030_madc_battery_remove(struct platform_device *pdev)
254 {
255         struct twl4030_madc_battery *bat = platform_get_drvdata(pdev);
256
257         power_supply_unregister(bat->psy);
258
259         iio_channel_release(bat->channel_vbat);
260         iio_channel_release(bat->channel_ichg);
261         iio_channel_release(bat->channel_temp);
262
263         return 0;
264 }
265
266 static struct platform_driver twl4030_madc_battery_driver = {
267         .driver = {
268                 .name = "twl4030_madc_battery",
269         },
270         .probe  = twl4030_madc_battery_probe,
271         .remove = twl4030_madc_battery_remove,
272 };
273 module_platform_driver(twl4030_madc_battery_driver);
274
275 MODULE_LICENSE("GPL");
276 MODULE_AUTHOR("Lukas Märdian <lukas@goldelico.com>");
277 MODULE_DESCRIPTION("twl4030_madc battery driver");
278 MODULE_ALIAS("platform:twl4030_madc_battery");