summaryrefslogtreecommitdiffstats
path: root/drivers/regulator/wm8994-regulator.c
blob: 35b2958d51064a84950deef280a14603b1e4e0da (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
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
/*
 * wm8994-regulator.c  --  Regulator driver for the WM8994
 *
 * 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/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/gpio.h>
#include <linux/slab.h>

#include <linux/mfd/wm8994/core.h>
#include <linux/mfd/wm8994/registers.h>
#include <linux/mfd/wm8994/pdata.h>

struct wm8994_ldo {
	int enable;
	bool is_enabled;
	struct regulator_dev *regulator;
	struct wm8994 *wm8994;
};

#define WM8994_LDO1_MAX_SELECTOR 0x7
#define WM8994_LDO2_MAX_SELECTOR 0x3

static int wm8994_ldo_enable(struct regulator_dev *rdev)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);

	/* If we have no soft control assume that the LDO is always enabled. */
	if (!ldo->enable)
		return 0;

	gpio_set_value(ldo->enable, 1);
	ldo->is_enabled = true;

	return 0;
}

static int wm8994_ldo_disable(struct regulator_dev *rdev)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);

	/* If we have no soft control assume that the LDO is always enabled. */
	if (!ldo->enable)
		return -EINVAL;

	gpio_set_value(ldo->enable, 0);
	ldo->is_enabled = false;

	return 0;
}

static int wm8994_ldo_is_enabled(struct regulator_dev *rdev)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);

	return ldo->is_enabled;
}

static int wm8994_ldo_enable_time(struct regulator_dev *rdev)
{
	/* 3ms is fairly conservative but this shouldn't be too performance
	 * critical; can be tweaked per-system if required. */
	return 3000;
}

static int wm8994_ldo1_list_voltage(struct regulator_dev *rdev,
				    unsigned int selector)
{
	if (selector > WM8994_LDO1_MAX_SELECTOR)
		return -EINVAL;

	return (selector * 100000) + 2400000;
}

static int wm8994_ldo1_get_voltage_sel(struct regulator_dev *rdev)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
	int val;

	val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_1);
	if (val < 0)
		return val;

	return (val & WM8994_LDO1_VSEL_MASK) >> WM8994_LDO1_VSEL_SHIFT;
}

static int wm8994_ldo1_set_voltage(struct regulator_dev *rdev,
				   int min_uV, int max_uV, unsigned *s)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
	int selector, v;

	selector = (min_uV - 2400000) / 100000;
	v = wm8994_ldo1_list_voltage(rdev, selector);
	if (v < 0 || v > max_uV)
		return -EINVAL;

	*s = selector;
	selector <<= WM8994_LDO1_VSEL_SHIFT;

	return wm8994_set_bits(ldo->wm8994, WM8994_LDO_1,
			       WM8994_LDO1_VSEL_MASK, selector);
}

static struct regulator_ops wm8994_ldo1_ops = {
	.enable = wm8994_ldo_enable,
	.disable = wm8994_ldo_disable,
	.is_enabled = wm8994_ldo_is_enabled,
	.enable_time = wm8994_ldo_enable_time,

	.list_voltage = wm8994_ldo1_list_voltage,
	.get_voltage_sel = wm8994_ldo1_get_voltage_sel,
	.set_voltage = wm8994_ldo1_set_voltage,
};

static int wm8994_ldo2_list_voltage(struct regulator_dev *rdev,
				    unsigned int selector)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);

	if (selector > WM8994_LDO2_MAX_SELECTOR)
		return -EINVAL;

	switch (ldo->wm8994->type) {
	case WM8994:
		return (selector * 100000) + 900000;
	case WM8958:
		return (selector * 100000) + 1000000;
	default:
		return -EINVAL;
	}
}

static int wm8994_ldo2_get_voltage_sel(struct regulator_dev *rdev)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
	int val;

	val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_2);
	if (val < 0)
		return val;

	return (val & WM8994_LDO2_VSEL_MASK) >> WM8994_LDO2_VSEL_SHIFT;
}

static int wm8994_ldo2_set_voltage(struct regulator_dev *rdev,
				   int min_uV, int max_uV, unsigned *s)
{
	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
	int selector, v;

	switch (ldo->wm8994->type) {
	case WM8994:
		selector = (min_uV - 900000) / 100000;
		break;
	case WM8958:
		selector = (min_uV - 1000000) / 100000;
		break;
	default:
		return -EINVAL;
	}

	v = wm8994_ldo2_list_voltage(rdev, selector);
	if (v < 0 || v > max_uV)
		return -EINVAL;

	*s = selector;
	selector <<= WM8994_LDO2_VSEL_SHIFT;

	return wm8994_set_bits(ldo->wm8994, WM8994_LDO_2,
			       WM8994_LDO2_VSEL_MASK, selector);
}

static struct regulator_ops wm8994_ldo2_ops = {
	.enable = wm8994_ldo_enable,
	.disable = wm8994_ldo_disable,
	.is_enabled = wm8994_ldo_is_enabled,
	.enable_time = wm8994_ldo_enable_time,

	.list_voltage = wm8994_ldo2_list_voltage,
	.get_voltage_sel = wm8994_ldo2_get_voltage_sel,
	.set_voltage = wm8994_ldo2_set_voltage,
};

static struct regulator_desc wm8994_ldo_desc[] = {
	{
		.name = "LDO1",
		.id = 1,
		.type = REGULATOR_VOLTAGE,
		.n_voltages = WM8994_LDO1_MAX_SELECTOR + 1,
		.ops = &wm8994_ldo1_ops,
		.owner = THIS_MODULE,
	},
	{
		.name = "LDO2",
		.id = 2,
		.type = REGULATOR_VOLTAGE,
		.n_voltages = WM8994_LDO2_MAX_SELECTOR + 1,
		.ops = &wm8994_ldo2_ops,
		.owner = THIS_MODULE,
	},
};

static __devinit int wm8994_ldo_probe(struct platform_device *pdev)
{
	struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
	int id = pdev->id % ARRAY_SIZE(pdata->ldo);
	struct wm8994_ldo *ldo;
	int ret;

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

	if (!pdata)
		return -ENODEV;

	ldo = kzalloc(sizeof(struct wm8994_ldo), GFP_KERNEL);
	if (ldo == NULL) {
		dev_err(&pdev->dev, "Unable to allocate private data\n");
		return -ENOMEM;
	}

	ldo->wm8994 = wm8994;

	if (pdata->ldo[id].enable && gpio_is_valid(pdata->ldo[id].enable)) {
		ldo->enable = pdata->ldo[id].enable;

		ret = gpio_request(ldo->enable, "WM8994 LDO enable");
		if (ret < 0) {
			dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n",
				ret);
			goto err;
		}

		ret = gpio_direction_output(ldo->enable, ldo->is_enabled);
		if (ret < 0) {
			dev_err(&pdev->dev, "Failed to set GPIO up: %d\n",
				ret);
			goto err_gpio;
		}
	} else
		ldo->is_enabled = true;

	ldo->regulator = regulator_register(&wm8994_ldo_desc[id], &pdev->dev,
					     pdata->ldo[id].init_data, ldo);
	if (IS_ERR(ldo->regulator)) {
		ret = PTR_ERR(ldo->regulator);
		dev_err(wm8994->dev, "Failed to register LDO%d: %d\n",
			id + 1, ret);
		goto err_gpio;
	}

	platform_set_drvdata(pdev, ldo);

	return 0;

err_gpio:
	if (gpio_is_valid(ldo->enable))
		gpio_free(ldo->enable);
err:
	kfree(ldo);
	return ret;
}

static __devexit int wm8994_ldo_remove(struct platform_device *pdev)
{
	struct wm8994_ldo *ldo = platform_get_drvdata(pdev);

	platform_set_drvdata(pdev, NULL);

	regulator_unregister(ldo->regulator);
	if (gpio_is_valid(ldo->enable))
		gpio_free(ldo->enable);
	kfree(ldo);

	return 0;
}

static struct platform_driver wm8994_ldo_driver = {
	.probe = wm8994_ldo_probe,
	.remove = __devexit_p(wm8994_ldo_remove),
	.driver		= {
		.name	= "wm8994-ldo",
		.owner	= THIS_MODULE,
	},
};

static int __init wm8994_ldo_init(void)
{
	int ret;

	ret = platform_driver_register(&wm8994_ldo_driver);
	if (ret != 0)
		pr_err("Failed to register Wm8994 GP LDO driver: %d\n", ret);

	return ret;
}
subsys_initcall(wm8994_ldo_init);

static void __exit wm8994_ldo_exit(void)
{
	platform_driver_unregister(&wm8994_ldo_driver);
}
module_exit(wm8994_ldo_exit);

/* Module information */
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("WM8994 LDO driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm8994-ldo");