xref: /linux/drivers/regulator/wm8994-regulator.c (revision 5148fa52a12fa1b97c730b2fe321f2aad7ea041c)
1 /*
2  * wm8994-regulator.c  --  Regulator driver for the WM8994
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/platform_device.h>
20 #include <linux/regulator/driver.h>
21 #include <linux/gpio.h>
22 #include <linux/slab.h>
23 
24 #include <linux/mfd/wm8994/core.h>
25 #include <linux/mfd/wm8994/registers.h>
26 #include <linux/mfd/wm8994/pdata.h>
27 
28 struct wm8994_ldo {
29 	int enable;
30 	bool is_enabled;
31 	struct regulator_dev *regulator;
32 	struct wm8994 *wm8994;
33 };
34 
35 #define WM8994_LDO1_MAX_SELECTOR 0x7
36 #define WM8994_LDO2_MAX_SELECTOR 0x3
37 
38 static int wm8994_ldo_enable(struct regulator_dev *rdev)
39 {
40 	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
41 
42 	/* If we have no soft control assume that the LDO is always enabled. */
43 	if (!ldo->enable)
44 		return 0;
45 
46 	gpio_set_value_cansleep(ldo->enable, 1);
47 	ldo->is_enabled = true;
48 
49 	return 0;
50 }
51 
52 static int wm8994_ldo_disable(struct regulator_dev *rdev)
53 {
54 	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
55 
56 	/* If we have no soft control assume that the LDO is always enabled. */
57 	if (!ldo->enable)
58 		return -EINVAL;
59 
60 	gpio_set_value_cansleep(ldo->enable, 0);
61 	ldo->is_enabled = false;
62 
63 	return 0;
64 }
65 
66 static int wm8994_ldo_is_enabled(struct regulator_dev *rdev)
67 {
68 	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
69 
70 	return ldo->is_enabled;
71 }
72 
73 static int wm8994_ldo_enable_time(struct regulator_dev *rdev)
74 {
75 	/* 3ms is fairly conservative but this shouldn't be too performance
76 	 * critical; can be tweaked per-system if required. */
77 	return 3000;
78 }
79 
80 static int wm8994_ldo1_list_voltage(struct regulator_dev *rdev,
81 				    unsigned int selector)
82 {
83 	if (selector > WM8994_LDO1_MAX_SELECTOR)
84 		return -EINVAL;
85 
86 	return (selector * 100000) + 2400000;
87 }
88 
89 static struct regulator_ops wm8994_ldo1_ops = {
90 	.enable = wm8994_ldo_enable,
91 	.disable = wm8994_ldo_disable,
92 	.is_enabled = wm8994_ldo_is_enabled,
93 	.enable_time = wm8994_ldo_enable_time,
94 
95 	.list_voltage = wm8994_ldo1_list_voltage,
96 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
97 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
98 };
99 
100 static int wm8994_ldo2_list_voltage(struct regulator_dev *rdev,
101 				    unsigned int selector)
102 {
103 	struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
104 
105 	if (selector > WM8994_LDO2_MAX_SELECTOR)
106 		return -EINVAL;
107 
108 	switch (ldo->wm8994->type) {
109 	case WM8994:
110 		return (selector * 100000) + 900000;
111 	case WM8958:
112 		return (selector * 100000) + 1000000;
113 	case WM1811:
114 		switch (selector) {
115 		case 0:
116 			return -EINVAL;
117 		default:
118 			return (selector * 100000) + 950000;
119 		}
120 		break;
121 	default:
122 		return -EINVAL;
123 	}
124 }
125 
126 static struct regulator_ops wm8994_ldo2_ops = {
127 	.enable = wm8994_ldo_enable,
128 	.disable = wm8994_ldo_disable,
129 	.is_enabled = wm8994_ldo_is_enabled,
130 	.enable_time = wm8994_ldo_enable_time,
131 
132 	.list_voltage = wm8994_ldo2_list_voltage,
133 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
134 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
135 };
136 
137 static const struct regulator_desc wm8994_ldo_desc[] = {
138 	{
139 		.name = "LDO1",
140 		.id = 1,
141 		.type = REGULATOR_VOLTAGE,
142 		.n_voltages = WM8994_LDO1_MAX_SELECTOR + 1,
143 		.vsel_reg = WM8994_LDO_1,
144 		.vsel_mask = WM8994_LDO1_VSEL_MASK,
145 		.ops = &wm8994_ldo1_ops,
146 		.owner = THIS_MODULE,
147 	},
148 	{
149 		.name = "LDO2",
150 		.id = 2,
151 		.type = REGULATOR_VOLTAGE,
152 		.n_voltages = WM8994_LDO2_MAX_SELECTOR + 1,
153 		.vsel_reg = WM8994_LDO_2,
154 		.vsel_mask = WM8994_LDO2_VSEL_MASK,
155 		.ops = &wm8994_ldo2_ops,
156 		.owner = THIS_MODULE,
157 	},
158 };
159 
160 static __devinit int wm8994_ldo_probe(struct platform_device *pdev)
161 {
162 	struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
163 	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
164 	int id = pdev->id % ARRAY_SIZE(pdata->ldo);
165 	struct regulator_config config = { };
166 	struct wm8994_ldo *ldo;
167 	int ret;
168 
169 	dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);
170 
171 	ldo = devm_kzalloc(&pdev->dev, sizeof(struct wm8994_ldo), GFP_KERNEL);
172 	if (ldo == NULL) {
173 		dev_err(&pdev->dev, "Unable to allocate private data\n");
174 		return -ENOMEM;
175 	}
176 
177 	ldo->wm8994 = wm8994;
178 
179 	if (pdata->ldo[id].enable && gpio_is_valid(pdata->ldo[id].enable)) {
180 		ldo->enable = pdata->ldo[id].enable;
181 
182 		ret = gpio_request_one(ldo->enable, 0, "WM8994 LDO enable");
183 		if (ret < 0) {
184 			dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n",
185 				ret);
186 			goto err;
187 		}
188 	} else
189 		ldo->is_enabled = true;
190 
191 	config.dev = wm8994->dev;
192 	config.driver_data = ldo;
193 	config.regmap = wm8994->regmap;
194 	if (pdata)
195 		config.init_data = pdata->ldo[id].init_data;
196 
197 	ldo->regulator = regulator_register(&wm8994_ldo_desc[id], &config);
198 	if (IS_ERR(ldo->regulator)) {
199 		ret = PTR_ERR(ldo->regulator);
200 		dev_err(wm8994->dev, "Failed to register LDO%d: %d\n",
201 			id + 1, ret);
202 		goto err_gpio;
203 	}
204 
205 	platform_set_drvdata(pdev, ldo);
206 
207 	return 0;
208 
209 err_gpio:
210 	if (gpio_is_valid(ldo->enable))
211 		gpio_free(ldo->enable);
212 err:
213 	return ret;
214 }
215 
216 static __devexit int wm8994_ldo_remove(struct platform_device *pdev)
217 {
218 	struct wm8994_ldo *ldo = platform_get_drvdata(pdev);
219 
220 	platform_set_drvdata(pdev, NULL);
221 
222 	regulator_unregister(ldo->regulator);
223 	if (gpio_is_valid(ldo->enable))
224 		gpio_free(ldo->enable);
225 
226 	return 0;
227 }
228 
229 static struct platform_driver wm8994_ldo_driver = {
230 	.probe = wm8994_ldo_probe,
231 	.remove = __devexit_p(wm8994_ldo_remove),
232 	.driver		= {
233 		.name	= "wm8994-ldo",
234 		.owner	= THIS_MODULE,
235 	},
236 };
237 
238 static int __init wm8994_ldo_init(void)
239 {
240 	int ret;
241 
242 	ret = platform_driver_register(&wm8994_ldo_driver);
243 	if (ret != 0)
244 		pr_err("Failed to register Wm8994 GP LDO driver: %d\n", ret);
245 
246 	return ret;
247 }
248 subsys_initcall(wm8994_ldo_init);
249 
250 static void __exit wm8994_ldo_exit(void)
251 {
252 	platform_driver_unregister(&wm8994_ldo_driver);
253 }
254 module_exit(wm8994_ldo_exit);
255 
256 /* Module information */
257 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
258 MODULE_DESCRIPTION("WM8994 LDO driver");
259 MODULE_LICENSE("GPL");
260 MODULE_ALIAS("platform:wm8994-ldo");
261