regulator: wm831x: Set the new rather than old value for DVS VSEL
[linux-2.6.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 #include <linux/slab.h>
23
24 #include <linux/mfd/wm831x/core.h>
25 #include <linux/mfd/wm831x/regulator.h>
26 #include <linux/mfd/wm831x/pdata.h>
27
28 #define WM831X_ISINK_MAX_NAME 7
29
30 struct wm831x_isink {
31         char name[WM831X_ISINK_MAX_NAME];
32         struct regulator_desc desc;
33         int reg;
34         struct wm831x *wm831x;
35         struct regulator_dev *regulator;
36 };
37
38 static int wm831x_isink_enable(struct regulator_dev *rdev)
39 {
40         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
41         struct wm831x *wm831x = isink->wm831x;
42         int ret;
43
44         /* We have a two stage enable: first start the ISINK... */
45         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA,
46                               WM831X_CS1_ENA);
47         if (ret != 0)
48                 return ret;
49
50         /* ...then enable drive */
51         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE,
52                               WM831X_CS1_DRIVE);
53         if (ret != 0)
54                 wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
55
56         return ret;
57
58 }
59
60 static int wm831x_isink_disable(struct regulator_dev *rdev)
61 {
62         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
63         struct wm831x *wm831x = isink->wm831x;
64         int ret;
65
66         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE, 0);
67         if (ret < 0)
68                 return ret;
69
70         ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
71         if (ret < 0)
72                 return ret;
73
74         return ret;
75
76 }
77
78 static int wm831x_isink_is_enabled(struct regulator_dev *rdev)
79 {
80         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
81         struct wm831x *wm831x = isink->wm831x;
82         int ret;
83
84         ret = wm831x_reg_read(wm831x, isink->reg);
85         if (ret < 0)
86                 return ret;
87
88         if ((ret & (WM831X_CS1_ENA | WM831X_CS1_DRIVE)) ==
89             (WM831X_CS1_ENA | WM831X_CS1_DRIVE))
90                 return 1;
91         else
92                 return 0;
93 }
94
95 static int wm831x_isink_set_current(struct regulator_dev *rdev,
96                                     int min_uA, int max_uA)
97 {
98         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
99         struct wm831x *wm831x = isink->wm831x;
100         int ret, i;
101
102         for (i = 0; i < ARRAY_SIZE(wm831x_isinkv_values); i++) {
103                 int val = wm831x_isinkv_values[i];
104                 if (min_uA <= val && val <= max_uA) {
105                         ret = wm831x_set_bits(wm831x, isink->reg,
106                                               WM831X_CS1_ISEL_MASK, i);
107                         return ret;
108                 }
109         }
110
111         return -EINVAL;
112 }
113
114 static int wm831x_isink_get_current(struct regulator_dev *rdev)
115 {
116         struct wm831x_isink *isink = rdev_get_drvdata(rdev);
117         struct wm831x *wm831x = isink->wm831x;
118         int ret;
119
120         ret = wm831x_reg_read(wm831x, isink->reg);
121         if (ret < 0)
122                 return ret;
123
124         ret &= WM831X_CS1_ISEL_MASK;
125         if (ret > WM831X_ISINK_MAX_ISEL)
126                 ret = WM831X_ISINK_MAX_ISEL;
127
128         return wm831x_isinkv_values[ret];
129 }
130
131 static struct regulator_ops wm831x_isink_ops = {
132         .is_enabled = wm831x_isink_is_enabled,
133         .enable = wm831x_isink_enable,
134         .disable = wm831x_isink_disable,
135         .set_current_limit = wm831x_isink_set_current,
136         .get_current_limit = wm831x_isink_get_current,
137 };
138
139 static irqreturn_t wm831x_isink_irq(int irq, void *data)
140 {
141         struct wm831x_isink *isink = data;
142
143         regulator_notifier_call_chain(isink->regulator,
144                                       REGULATOR_EVENT_OVER_CURRENT,
145                                       NULL);
146
147         return IRQ_HANDLED;
148 }
149
150
151 static __devinit int wm831x_isink_probe(struct platform_device *pdev)
152 {
153         struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
154         struct wm831x_pdata *pdata = wm831x->dev->platform_data;
155         struct wm831x_isink *isink;
156         int id = pdev->id % ARRAY_SIZE(pdata->isink);
157         struct resource *res;
158         int ret, irq;
159
160         dev_dbg(&pdev->dev, "Probing ISINK%d\n", id + 1);
161
162         if (pdata == NULL || pdata->isink[id] == NULL)
163                 return -ENODEV;
164
165         isink = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_isink),
166                              GFP_KERNEL);
167         if (isink == NULL) {
168                 dev_err(&pdev->dev, "Unable to allocate private data\n");
169                 return -ENOMEM;
170         }
171
172         isink->wm831x = wm831x;
173
174         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
175         if (res == NULL) {
176                 dev_err(&pdev->dev, "No I/O resource\n");
177                 ret = -EINVAL;
178                 goto err;
179         }
180         isink->reg = res->start;
181
182         /* For current parts this is correct; probably need to revisit
183          * in future.
184          */
185         snprintf(isink->name, sizeof(isink->name), "ISINK%d", id + 1);
186         isink->desc.name = isink->name;
187         isink->desc.id = id;
188         isink->desc.ops = &wm831x_isink_ops;
189         isink->desc.type = REGULATOR_CURRENT;
190         isink->desc.owner = THIS_MODULE;
191
192         isink->regulator = regulator_register(&isink->desc, &pdev->dev,
193                                              pdata->isink[id], isink, NULL);
194         if (IS_ERR(isink->regulator)) {
195                 ret = PTR_ERR(isink->regulator);
196                 dev_err(wm831x->dev, "Failed to register ISINK%d: %d\n",
197                         id + 1, ret);
198                 goto err;
199         }
200
201         irq = platform_get_irq(pdev, 0);
202         ret = request_threaded_irq(irq, NULL, wm831x_isink_irq,
203                                    IRQF_TRIGGER_RISING, isink->name, isink);
204         if (ret != 0) {
205                 dev_err(&pdev->dev, "Failed to request ISINK IRQ %d: %d\n",
206                         irq, ret);
207                 goto err_regulator;
208         }
209
210         platform_set_drvdata(pdev, isink);
211
212         return 0;
213
214 err_regulator:
215         regulator_unregister(isink->regulator);
216 err:
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
224         platform_set_drvdata(pdev, NULL);
225
226         free_irq(platform_get_irq(pdev, 0), isink);
227
228         regulator_unregister(isink->regulator);
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                 .owner  = THIS_MODULE,
239         },
240 };
241
242 static int __init wm831x_isink_init(void)
243 {
244         int ret;
245         ret = platform_driver_register(&wm831x_isink_driver);
246         if (ret != 0)
247                 pr_err("Failed to register WM831x ISINK driver: %d\n", ret);
248
249         return ret;
250 }
251 subsys_initcall(wm831x_isink_init);
252
253 static void __exit wm831x_isink_exit(void)
254 {
255         platform_driver_unregister(&wm831x_isink_driver);
256 }
257 module_exit(wm831x_isink_exit);
258
259 /* Module information */
260 MODULE_AUTHOR("Mark Brown");
261 MODULE_DESCRIPTION("WM831x current sink driver");
262 MODULE_LICENSE("GPL");
263 MODULE_ALIAS("platform:wm831x-isink");