regulator: Initialise wm831x structure pointor for ISINK driver
[daniel-s-linux-stuff:linux-kernel.git] / drivers / regulator / wm831x-isink.c
1 /*
2  * wm831x-isink.c  --  Current sink driver for the WM831x series
3  *
4  * Copyright 2009 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  */
13
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/init.h>
17 #include <linux/bitops.h>
18 #include <linux/err.h>
19 #include <linux/i2c.h>
20 #include <linux/platform_device.h>
21 #include <linux/regulator/driver.h>
22
23 #include <linux/mfd/wm831x/core.h>
24 #include <linux/mfd/wm831x/regulator.h>
25 #include <linux/mfd/wm831x/pdata.h>
26
27 #define WM831X_ISINK_MAX_NAME 7
28
29 struct wm831x_isink {
30         char name[WM831X_ISINK_MAX_NAME];
31         struct regulator_desc desc;
32         int reg;
33         struct wm831x *wm831x;
34         struct regulator_dev *regulator;
35 };
36
37 static int wm831x_isink_enable(struct regulator_dev *rdev)
38 {
39         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
40         struct wm831x *wm831x = isink->wm831x;
41         int ret;
42
43         /* We have a two stage enable: first start the ISINK... */
44         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA,
45                               WM831X_CS1_ENA);
46         if (ret != 0)
47                 return ret;
48
49         /* ...then enable drive */
50         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE,
51                               WM831X_CS1_DRIVE);
52         if (ret != 0)
53                 wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
54
55         return ret;
56
57 }
58
59 static int wm831x_isink_disable(struct regulator_dev *rdev)
60 {
61         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
62         struct wm831x *wm831x = isink->wm831x;
63         int ret;
64
65         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE, 0);
66         if (ret < 0)
67                 return ret;
68
69         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
70         if (ret < 0)
71                 return ret;
72
73         return ret;
74
75 }
76
77 static int wm831x_isink_is_enabled(struct regulator_dev *rdev)
78 {
79         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
80         struct wm831x *wm831x = isink->wm831x;
81         int ret;
82
83         ret = wm831x_reg_read(wm831x, isink->reg);
84         if (ret < 0)
85                 return ret;
86
87         if ((ret & (WM831X_CS1_ENA | WM831X_CS1_DRIVE)) ==
88             (WM831X_CS1_ENA | WM831X_CS1_DRIVE))
89                 return 1;
90         else
91                 return 0;
92 }
93
94 static int wm831x_isink_set_current(struct regulator_dev *rdev,
95                                     int min_uA, int max_uA)
96 {
97         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
98         struct wm831x *wm831x = isink->wm831x;
99         int ret, i;
100
101         for (i = 0; i < ARRAY_SIZE(wm831x_isinkv_values); i++) {
102                 int val = wm831x_isinkv_values[i];
103                 if (min_uA >= val && val <= max_uA) {
104                         ret = wm831x_set_bits(wm831x, isink->reg,
105                                               WM831X_CS1_ISEL_MASK, i);
106                         return ret;
107                 }
108         }
109
110         return -EINVAL;
111 }
112
113 static int wm831x_isink_get_current(struct regulator_dev *rdev)
114 {
115         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
116         struct wm831x *wm831x = isink->wm831x;
117         int ret;
118
119         ret = wm831x_reg_read(wm831x, isink->reg);
120         if (ret < 0)
121                 return ret;
122
123         ret &= WM831X_CS1_ISEL_MASK;
124         if (ret > WM831X_ISINK_MAX_ISEL)
125                 ret = WM831X_ISINK_MAX_ISEL;
126
127         return wm831x_isinkv_values[ret];
128 }
129
130 static struct regulator_ops wm831x_isink_ops = {
131         .is_enabled = wm831x_isink_is_enabled,
132         .enable = wm831x_isink_enable,
133         .disable = wm831x_isink_disable,
134         .set_current_limit = wm831x_isink_set_current,
135         .get_current_limit = wm831x_isink_get_current,
136 };
137
138 static irqreturn_t wm831x_isink_irq(int irq, void *data)
139 {
140         struct wm831x_isink *isink = data;
141
142         regulator_notifier_call_chain(isink->regulator,
143                                       REGULATOR_EVENT_OVER_CURRENT,
144                                       NULL);
145
146         return IRQ_HANDLED;
147 }
148
149
150 static __devinit int wm831x_isink_probe(struct platform_device *pdev)
151 {
152         struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
153         struct wm831x_pdata *pdata = wm831x->dev->platform_data;
154         struct wm831x_isink *isink;
155         int id = pdev->id % ARRAY_SIZE(pdata->isink);
156         struct resource *res;
157         int ret, irq;
158
159         dev_dbg(&pdev->dev, "Probing ISINK%d\n", id + 1);
160
161         if (pdata == NULL || pdata->isink[id] == NULL)
162                 return -ENODEV;
163
164         isink = kzalloc(sizeof(struct wm831x_isink), GFP_KERNEL);
165         if (isink == NULL) {
166                 dev_err(&pdev->dev, "Unable to allocate private data\n");
167                 return -ENOMEM;
168         }
169
170         isink->wm831x = wm831x;
171
172         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
173         if (res == NULL) {
174                 dev_err(&pdev->dev, "No I/O resource\n");
175                 ret = -EINVAL;
176                 goto err;
177         }
178         isink->reg = res->start;
179
180         /* For current parts this is correct; probably need to revisit
181          * in future.
182          */
183         snprintf(isink->name, sizeof(isink->name), "ISINK%d", id + 1);
184         isink->desc.name = isink->name;
185         isink->desc.id = id;
186         isink->desc.ops = &wm831x_isink_ops;
187         isink->desc.type = REGULATOR_CURRENT;
188         isink->desc.owner = THIS_MODULE;
189
190         isink->regulator = regulator_register(&isink->desc, &pdev->dev,
191                                              pdata->isink[id], isink);
192         if (IS_ERR(isink->regulator)) {
193                 ret = PTR_ERR(isink->regulator);
194                 dev_err(wm831x->dev, "Failed to register ISINK%d: %d\n",
195                         id + 1, ret);
196                 goto err;
197         }
198
199         irq = platform_get_irq(pdev, 0);
200         ret = wm831x_request_irq(wm831x, irq, wm831x_isink_irq,
201                                  IRQF_TRIGGER_RISING, isink->name,
202                                  isink);
203         if (ret != 0) {
204                 dev_err(&pdev->dev, "Failed to request ISINK IRQ %d: %d\n",
205                         irq, ret);
206                 goto err_regulator;
207         }
208
209         platform_set_drvdata(pdev, isink);
210
211         return 0;
212
213 err_regulator:
214         regulator_unregister(isink->regulator);
215 err:
216         kfree(isink);
217         return ret;
218 }
219
220 static __devexit int wm831x_isink_remove(struct platform_device *pdev)
221 {
222         struct wm831x_isink *isink = platform_get_drvdata(pdev);
223         struct wm831x *wm831x = isink->wm831x;
224
225         wm831x_free_irq(wm831x, platform_get_irq(pdev, 0), isink);
226
227         regulator_unregister(isink->regulator);
228         kfree(isink);
229
230         return 0;
231 }
232
233 static struct platform_driver wm831x_isink_driver = {
234         .probe = wm831x_isink_probe,
235         .remove = __devexit_p(wm831x_isink_remove),
236         .driver         = {
237                 .name   = "wm831x-isink",
238         },
239 };
240
241 static int __init wm831x_isink_init(void)
242 {
243         int ret;
244         ret = platform_driver_register(&wm831x_isink_driver);
245         if (ret != 0)
246                 pr_err("Failed to register WM831x ISINK driver: %d\n", ret);
247
248         return ret;
249 }
250 subsys_initcall(wm831x_isink_init);
251
252 static void __exit wm831x_isink_exit(void)
253 {
254         platform_driver_unregister(&wm831x_isink_driver);
255 }
256 module_exit(wm831x_isink_exit);
257
258 /* Module information */
259 MODULE_AUTHOR("Mark Brown");
260 MODULE_DESCRIPTION("WM831x current sink driver");
261 MODULE_LICENSE("GPL");
262 MODULE_ALIAS("platform:wm831x-isink");