USB: usb-storage: fix initializations of urb fields
[linux-2.6.git] / drivers / power / wm831x_backup.c
1 /*
2  * Backup battery driver for Wolfson Microelectronics wm831x PMICs
3  *
4  * Copyright 2009 Wolfson Microelectronics PLC.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10
11 #include <linux/module.h>
12 #include <linux/err.h>
13 #include <linux/platform_device.h>
14 #include <linux/power_supply.h>
15 #include <linux/slab.h>
16
17 #include <linux/mfd/wm831x/core.h>
18 #include <linux/mfd/wm831x/auxadc.h>
19 #include <linux/mfd/wm831x/pmu.h>
20 #include <linux/mfd/wm831x/pdata.h>
21
22 struct wm831x_backup {
23         struct wm831x *wm831x;
24         struct power_supply backup;
25 };
26
27 static int wm831x_backup_read_voltage(struct wm831x *wm831x,
28                                      enum wm831x_auxadc src,
29                                      union power_supply_propval *val)
30 {
31         int ret;
32
33         ret = wm831x_auxadc_read_uv(wm831x, src);
34         if (ret >= 0)
35                 val->intval = ret;
36
37         return ret;
38 }
39
40 /*********************************************************************
41  *              Backup supply properties
42  *********************************************************************/
43
44 static void wm831x_config_backup(struct wm831x *wm831x)
45 {
46         struct wm831x_pdata *wm831x_pdata = wm831x->dev->platform_data;
47         struct wm831x_backup_pdata *pdata;
48         int ret, reg;
49
50         if (!wm831x_pdata || !wm831x_pdata->backup) {
51                 dev_warn(wm831x->dev,
52                          "No backup battery charger configuration\n");
53                 return;
54         }
55
56         pdata = wm831x_pdata->backup;
57
58         reg = 0;
59
60         if (pdata->charger_enable)
61                 reg |= WM831X_BKUP_CHG_ENA | WM831X_BKUP_BATT_DET_ENA;
62         if (pdata->no_constant_voltage)
63                 reg |= WM831X_BKUP_CHG_MODE;
64
65         switch (pdata->vlim) {
66         case 2500:
67                 break;
68         case 3100:
69                 reg |= WM831X_BKUP_CHG_VLIM;
70                 break;
71         default:
72                 dev_err(wm831x->dev, "Invalid backup voltage limit %dmV\n",
73                         pdata->vlim);
74         }
75
76         switch (pdata->ilim) {
77         case 100:
78                 break;
79         case 200:
80                 reg |= 1;
81                 break;
82         case 300:
83                 reg |= 2;
84                 break;
85         case 400:
86                 reg |= 3;
87                 break;
88         default:
89                 dev_err(wm831x->dev, "Invalid backup current limit %duA\n",
90                         pdata->ilim);
91         }
92
93         ret = wm831x_reg_unlock(wm831x);
94         if (ret != 0) {
95                 dev_err(wm831x->dev, "Failed to unlock registers: %d\n", ret);
96                 return;
97         }
98
99         ret = wm831x_set_bits(wm831x, WM831X_BACKUP_CHARGER_CONTROL,
100                               WM831X_BKUP_CHG_ENA_MASK |
101                               WM831X_BKUP_CHG_MODE_MASK |
102                               WM831X_BKUP_BATT_DET_ENA_MASK |
103                               WM831X_BKUP_CHG_VLIM_MASK |
104                               WM831X_BKUP_CHG_ILIM_MASK,
105                               reg);
106         if (ret != 0)
107                 dev_err(wm831x->dev,
108                         "Failed to set backup charger config: %d\n", ret);
109
110         wm831x_reg_lock(wm831x);
111 }
112
113 static int wm831x_backup_get_prop(struct power_supply *psy,
114                                   enum power_supply_property psp,
115                                   union power_supply_propval *val)
116 {
117         struct wm831x_backup *devdata = dev_get_drvdata(psy->dev->parent);
118         struct wm831x *wm831x = devdata->wm831x;
119         int ret = 0;
120
121         ret = wm831x_reg_read(wm831x, WM831X_BACKUP_CHARGER_CONTROL);
122         if (ret < 0)
123                 return ret;
124
125         switch (psp) {
126         case POWER_SUPPLY_PROP_STATUS:
127                 if (ret & WM831X_BKUP_CHG_STS)
128                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
129                 else
130                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
131                 break;
132
133         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
134                 ret = wm831x_backup_read_voltage(wm831x, WM831X_AUX_BKUP_BATT,
135                                                 val);
136                 break;
137
138         case POWER_SUPPLY_PROP_PRESENT:
139                 if (ret & WM831X_BKUP_CHG_STS)
140                         val->intval = 1;
141                 else
142                         val->intval = 0;
143                 break;
144
145         default:
146                 ret = -EINVAL;
147                 break;
148         }
149
150         return ret;
151 }
152
153 static enum power_supply_property wm831x_backup_props[] = {
154         POWER_SUPPLY_PROP_STATUS,
155         POWER_SUPPLY_PROP_VOLTAGE_NOW,
156         POWER_SUPPLY_PROP_PRESENT,
157 };
158
159 /*********************************************************************
160  *              Initialisation
161  *********************************************************************/
162
163 static __devinit int wm831x_backup_probe(struct platform_device *pdev)
164 {
165         struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
166         struct wm831x_backup *devdata;
167         struct power_supply *backup;
168         int ret;
169
170         devdata = kzalloc(sizeof(struct wm831x_backup), GFP_KERNEL);
171         if (devdata == NULL)
172                 return -ENOMEM;
173
174         devdata->wm831x = wm831x;
175         platform_set_drvdata(pdev, devdata);
176
177         backup = &devdata->backup;
178
179         /* We ignore configuration failures since we can still read
180          * back the status without enabling the charger (which may
181          * already be enabled anyway).
182          */
183         wm831x_config_backup(wm831x);
184
185         backup->name = "wm831x-backup";
186         backup->type = POWER_SUPPLY_TYPE_BATTERY;
187         backup->properties = wm831x_backup_props;
188         backup->num_properties = ARRAY_SIZE(wm831x_backup_props);
189         backup->get_property = wm831x_backup_get_prop;
190         ret = power_supply_register(&pdev->dev, backup);
191         if (ret)
192                 goto err_kmalloc;
193
194         return ret;
195
196 err_kmalloc:
197         kfree(devdata);
198         return ret;
199 }
200
201 static __devexit int wm831x_backup_remove(struct platform_device *pdev)
202 {
203         struct wm831x_backup *devdata = platform_get_drvdata(pdev);
204
205         power_supply_unregister(&devdata->backup);
206         kfree(devdata);
207
208         return 0;
209 }
210
211 static struct platform_driver wm831x_backup_driver = {
212         .probe = wm831x_backup_probe,
213         .remove = __devexit_p(wm831x_backup_remove),
214         .driver = {
215                 .name = "wm831x-backup",
216         },
217 };
218
219 static int __init wm831x_backup_init(void)
220 {
221         return platform_driver_register(&wm831x_backup_driver);
222 }
223 module_init(wm831x_backup_init);
224
225 static void __exit wm831x_backup_exit(void)
226 {
227         platform_driver_unregister(&wm831x_backup_driver);
228 }
229 module_exit(wm831x_backup_exit);
230
231 MODULE_DESCRIPTION("Backup battery charger driver for WM831x PMICs");
232 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
233 MODULE_LICENSE("GPL");
234 MODULE_ALIAS("platform:wm831x-backup");