summaryrefslogtreecommitdiffstats
path: root/drivers/regulator/wm831x-isink.c
blob: 6c446cd6ad546839aa455d2302fff558921ea3c3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
/*
 * wm831x-isink.c  --  Current sink driver for the WM831x series
 *
 * Copyright 2009 Wolfson Microelectronics PLC.
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/slab.h>

#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/regulator.h>
#include <linux/mfd/wm831x/pdata.h>

#define WM831X_ISINK_MAX_NAME 7

struct wm831x_isink {
	char name[WM831X_ISINK_MAX_NAME];
	struct regulator_desc desc;
	int reg;
	struct wm831x *wm831x;
	struct regulator_dev *regulator;
};

static int wm831x_isink_enable(struct regulator_dev *rdev)
{
	struct wm831x_isink *isink = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = isink->wm831x;
	int ret;

	/* We have a two stage enable: first start the ISINK... */
	ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA,
			      WM831X_CS1_ENA);
	if (ret != 0)
		return ret;

	/* ...then enable drive */
	ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE,
			      WM831X_CS1_DRIVE);
	if (ret != 0)
		wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);

	return ret;

}

static int wm831x_isink_disable(struct regulator_dev *rdev)
{
	struct wm831x_isink *isink = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = isink->wm831x;
	int ret;

	ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_DRIVE, 0);
	if (ret < 0)
		return ret;

	ret = wm831x_set_bits(wm831x, isink->reg, WM831X_CS1_ENA, 0);
	if (ret < 0)
		return ret;

	return ret;

}

static int wm831x_isink_is_enabled(struct regulator_dev *rdev)
{
	struct wm831x_isink *isink = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = isink->wm831x;
	int ret;

	ret = wm831x_reg_read(wm831x, isink->reg);
	if (ret < 0)
		return ret;

	if ((ret & (WM831X_CS1_ENA | WM831X_CS1_DRIVE)) ==
	    (WM831X_CS1_ENA | WM831X_CS1_DRIVE))
		return 1;
	else
		return 0;
}

static int wm831x_isink_set_current(struct regulator_dev *rdev,
				    int min_uA, int max_uA)
{
	struct wm831x_isink *isink = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = isink->wm831x;
	int ret, i;

	for (i = 0; i < ARRAY_SIZE(wm831x_isinkv_values); i++) {
		int val = wm831x_isinkv_values[i];
		if (min_uA >= val && val <= max_uA) {
			ret = wm831x_set_bits(wm831x, isink->reg,
					      WM831X_CS1_ISEL_MASK, i);
			return ret;
		}
	}

	return -EINVAL;
}

static int wm831x_isink_get_current(struct regulator_dev *rdev)
{
	struct wm831x_isink *isink = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = isink->wm831x;
	int ret;

	ret = wm831x_reg_read(wm831x, isink->reg);
	if (ret < 0)
		return ret;

	ret &= WM831X_CS1_ISEL_MASK;
	if (ret > WM831X_ISINK_MAX_ISEL)
		ret = WM831X_ISINK_MAX_ISEL;

	return wm831x_isinkv_values[ret];
}

static struct regulator_ops wm831x_isink_ops = {
	.is_enabled = wm831x_isink_is_enabled,
	.enable = wm831x_isink_enable,
	.disable = wm831x_isink_disable,
	.set_current_limit = wm831x_isink_set_current,
	.get_current_limit = wm831x_isink_get_current,
};

static irqreturn_t wm831x_isink_irq(int irq, void *data)
{
	struct wm831x_isink *isink = data;

	regulator_notifier_call_chain(isink->regulator,
				      REGULATOR_EVENT_OVER_CURRENT,
				      NULL);

	return IRQ_HANDLED;
}


static __devinit int wm831x_isink_probe(struct platform_device *pdev)
{
	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
	struct wm831x_pdata *pdata = wm831x->dev->platform_data;
	struct wm831x_isink *isink;
	int id = pdev->id % ARRAY_SIZE(pdata->isink);
	struct resource *res;
	int ret, irq;

	dev_dbg(&pdev->dev, "Probing ISINK%d\n", id + 1);

	if (pdata == NULL || pdata->isink[id] == NULL)
		return -ENODEV;

	isink = kzalloc(sizeof(struct wm831x_isink), GFP_KERNEL);
	if (isink == NULL) {
		dev_err(&pdev->dev, "Unable to allocate private data\n");
		return -ENOMEM;
	}

	isink->wm831x = wm831x;

	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
	if (res == NULL) {
		dev_err(&pdev->dev, "No I/O resource\n");
		ret = -EINVAL;
		goto err;
	}
	isink->reg = res->start;

	/* For current parts this is correct; probably need to revisit
	 * in future.
	 */
	snprintf(isink->name, sizeof(isink->name), "ISINK%d", id + 1);
	isink->desc.name = isink->name;
	isink->desc.id = id;
	isink->desc.ops = &wm831x_isink_ops;
	isink->desc.type = REGULATOR_CURRENT;
	isink->desc.owner = THIS_MODULE;

	isink->regulator = regulator_register(&isink->desc, &pdev->dev,
					     pdata->isink[id], isink);
	if (IS_ERR(isink->regulator)) {
		ret = PTR_ERR(isink->regulator);
		dev_err(wm831x->dev, "Failed to register ISINK%d: %d\n",
			id + 1, ret);
		goto err;
	}

	irq = platform_get_irq(pdev, 0);
	ret = wm831x_request_irq(wm831x, irq, wm831x_isink_irq,
				 IRQF_TRIGGER_RISING, isink->name,
				 isink);
	if (ret != 0) {
		dev_err(&pdev->dev, "Failed to request ISINK IRQ %d: %d\n",
			irq, ret);
		goto err_regulator;
	}

	platform_set_drvdata(pdev, isink);

	return 0;

err_regulator:
	regulator_unregister(isink->regulator);
err:
	kfree(isink);
	return ret;
}

static __devexit int wm831x_isink_remove(struct platform_device *pdev)
{
	struct wm831x_isink *isink = platform_get_drvdata(pdev);
	struct wm831x *wm831x = isink->wm831x;

	platform_set_drvdata(pdev, NULL);

	wm831x_free_irq(wm831x, platform_get_irq(pdev, 0), isink);

	regulator_unregister(isink->regulator);
	kfree(isink);

	return 0;
}

static struct platform_driver wm831x_isink_driver = {
	.probe = wm831x_isink_probe,
	.remove = __devexit_p(wm831x_isink_remove),
	.driver		= {
		.name	= "wm831x-isink",
		.owner	= THIS_MODULE,
	},
};

static int __init wm831x_isink_init(void)
{
	int ret;
	ret = platform_driver_register(&wm831x_isink_driver);
	if (ret != 0)
		pr_err("Failed to register WM831x ISINK driver: %d\n", ret);

	return ret;
}
subsys_initcall(wm831x_isink_init);

static void __exit wm831x_isink_exit(void)
{
	platform_driver_unregister(&wm831x_isink_driver);
}
module_exit(wm831x_isink_exit);

/* Module information */
MODULE_AUTHOR("Mark Brown");
MODULE_DESCRIPTION("WM831x current sink driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-isink");