1 /*
2  * Regulator support for WM8400
3  *
4  * Copyright 2008 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
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of the
11  * License, or (at your option) any later version.
12  *
13  */
14 
15 #include <linux/bug.h>
16 #include <linux/err.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/regulator/driver.h>
20 #include <linux/mfd/wm8400-private.h>
21 
22 static int wm8400_ldo_list_voltage(struct regulator_dev *dev,
23 				   unsigned selector)
24 {
25 	if (selector > WM8400_LDO1_VSEL_MASK)
26 		return -EINVAL;
27 
28 	if (selector < 15)
29 		return 900000 + (selector * 50000);
30 	else
31 		return 1700000 + ((selector - 15) * 100000);
32 }
33 
34 static int wm8400_ldo_map_voltage(struct regulator_dev *dev,
35 				  int min_uV, int max_uV)
36 {
37 	u16 val;
38 	int volt;
39 
40 	if (min_uV < 900000 || min_uV > 3300000)
41 		return -EINVAL;
42 
43 	if (min_uV < 1700000) /* Steps of 50mV from 900mV;  */
44 		val = DIV_ROUND_UP(min_uV - 900000, 50000);
45 	else /* Steps of 100mV from 1700mV */
46 		val = DIV_ROUND_UP(min_uV - 1700000, 100000) + 15;
47 
48 	volt = wm8400_ldo_list_voltage(dev, val);
49 	if (volt < min_uV || volt > max_uV)
50 		return -EINVAL;
51 
52 	return val;
53 }
54 
55 static struct regulator_ops wm8400_ldo_ops = {
56 	.is_enabled = regulator_is_enabled_regmap,
57 	.enable = regulator_enable_regmap,
58 	.disable = regulator_disable_regmap,
59 	.list_voltage = wm8400_ldo_list_voltage,
60 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
61 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
62 	.map_voltage = wm8400_ldo_map_voltage,
63 };
64 
65 static unsigned int wm8400_dcdc_get_mode(struct regulator_dev *dev)
66 {
67 	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
68 	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
69 	u16 data[2];
70 	int ret;
71 
72 	ret = wm8400_block_read(wm8400, WM8400_DCDC1_CONTROL_1 + offset, 2,
73 				data);
74 	if (ret != 0)
75 		return 0;
76 
77 	/* Datasheet: hibernate */
78 	if (data[0] & WM8400_DC1_SLEEP)
79 		return REGULATOR_MODE_STANDBY;
80 
81 	/* Datasheet: standby */
82 	if (!(data[0] & WM8400_DC1_ACTIVE))
83 		return REGULATOR_MODE_IDLE;
84 
85 	/* Datasheet: active with or without force PWM */
86 	if (data[1] & WM8400_DC1_FRC_PWM)
87 		return REGULATOR_MODE_FAST;
88 	else
89 		return REGULATOR_MODE_NORMAL;
90 }
91 
92 static int wm8400_dcdc_set_mode(struct regulator_dev *dev, unsigned int mode)
93 {
94 	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
95 	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
96 	int ret;
97 
98 	switch (mode) {
99 	case REGULATOR_MODE_FAST:
100 		/* Datasheet: active with force PWM */
101 		ret = wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_2 + offset,
102 				      WM8400_DC1_FRC_PWM, WM8400_DC1_FRC_PWM);
103 		if (ret != 0)
104 			return ret;
105 
106 		return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
107 				       WM8400_DC1_ACTIVE | WM8400_DC1_SLEEP,
108 				       WM8400_DC1_ACTIVE);
109 
110 	case REGULATOR_MODE_NORMAL:
111 		/* Datasheet: active */
112 		ret = wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_2 + offset,
113 				      WM8400_DC1_FRC_PWM, 0);
114 		if (ret != 0)
115 			return ret;
116 
117 		return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
118 				       WM8400_DC1_ACTIVE | WM8400_DC1_SLEEP,
119 				       WM8400_DC1_ACTIVE);
120 
121 	case REGULATOR_MODE_IDLE:
122 		/* Datasheet: standby */
123 		return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
124 				       WM8400_DC1_ACTIVE | WM8400_DC1_SLEEP, 0);
125 	default:
126 		return -EINVAL;
127 	}
128 }
129 
130 static unsigned int wm8400_dcdc_get_optimum_mode(struct regulator_dev *dev,
131 						 int input_uV, int output_uV,
132 						 int load_uA)
133 {
134 	return REGULATOR_MODE_NORMAL;
135 }
136 
137 static struct regulator_ops wm8400_dcdc_ops = {
138 	.is_enabled = regulator_is_enabled_regmap,
139 	.enable = regulator_enable_regmap,
140 	.disable = regulator_disable_regmap,
141 	.list_voltage = regulator_list_voltage_linear,
142 	.map_voltage = regulator_map_voltage_linear,
143 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
144 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
145 	.get_mode = wm8400_dcdc_get_mode,
146 	.set_mode = wm8400_dcdc_set_mode,
147 	.get_optimum_mode = wm8400_dcdc_get_optimum_mode,
148 };
149 
150 static struct regulator_desc regulators[] = {
151 	{
152 		.name = "LDO1",
153 		.id = WM8400_LDO1,
154 		.ops = &wm8400_ldo_ops,
155 		.enable_reg = WM8400_LDO1_CONTROL,
156 		.enable_mask = WM8400_LDO1_ENA,
157 		.n_voltages = WM8400_LDO1_VSEL_MASK + 1,
158 		.vsel_reg = WM8400_LDO1_CONTROL,
159 		.vsel_mask = WM8400_LDO1_VSEL_MASK,
160 		.type = REGULATOR_VOLTAGE,
161 		.owner = THIS_MODULE,
162 	},
163 	{
164 		.name = "LDO2",
165 		.id = WM8400_LDO2,
166 		.ops = &wm8400_ldo_ops,
167 		.enable_reg = WM8400_LDO2_CONTROL,
168 		.enable_mask = WM8400_LDO2_ENA,
169 		.n_voltages = WM8400_LDO2_VSEL_MASK + 1,
170 		.type = REGULATOR_VOLTAGE,
171 		.vsel_reg = WM8400_LDO2_CONTROL,
172 		.vsel_mask = WM8400_LDO2_VSEL_MASK,
173 		.owner = THIS_MODULE,
174 	},
175 	{
176 		.name = "LDO3",
177 		.id = WM8400_LDO3,
178 		.ops = &wm8400_ldo_ops,
179 		.enable_reg = WM8400_LDO3_CONTROL,
180 		.enable_mask = WM8400_LDO3_ENA,
181 		.n_voltages = WM8400_LDO3_VSEL_MASK + 1,
182 		.vsel_reg = WM8400_LDO3_CONTROL,
183 		.vsel_mask = WM8400_LDO3_VSEL_MASK,
184 		.type = REGULATOR_VOLTAGE,
185 		.owner = THIS_MODULE,
186 	},
187 	{
188 		.name = "LDO4",
189 		.id = WM8400_LDO4,
190 		.ops = &wm8400_ldo_ops,
191 		.enable_reg = WM8400_LDO4_CONTROL,
192 		.enable_mask = WM8400_LDO4_ENA,
193 		.n_voltages = WM8400_LDO4_VSEL_MASK + 1,
194 		.vsel_reg = WM8400_LDO4_CONTROL,
195 		.vsel_mask = WM8400_LDO4_VSEL_MASK,
196 		.type = REGULATOR_VOLTAGE,
197 		.owner = THIS_MODULE,
198 	},
199 	{
200 		.name = "DCDC1",
201 		.id = WM8400_DCDC1,
202 		.ops = &wm8400_dcdc_ops,
203 		.enable_reg = WM8400_DCDC1_CONTROL_1,
204 		.enable_mask = WM8400_DC1_ENA_MASK,
205 		.n_voltages = WM8400_DC1_VSEL_MASK + 1,
206 		.vsel_reg = WM8400_DCDC1_CONTROL_1,
207 		.vsel_mask = WM8400_DC1_VSEL_MASK,
208 		.min_uV = 850000,
209 		.uV_step = 25000,
210 		.type = REGULATOR_VOLTAGE,
211 		.owner = THIS_MODULE,
212 	},
213 	{
214 		.name = "DCDC2",
215 		.id = WM8400_DCDC2,
216 		.ops = &wm8400_dcdc_ops,
217 		.enable_reg = WM8400_DCDC2_CONTROL_1,
218 		.enable_mask = WM8400_DC1_ENA_MASK,
219 		.n_voltages = WM8400_DC2_VSEL_MASK + 1,
220 		.vsel_reg = WM8400_DCDC2_CONTROL_1,
221 		.vsel_mask = WM8400_DC2_VSEL_MASK,
222 		.min_uV = 850000,
223 		.uV_step = 25000,
224 		.type = REGULATOR_VOLTAGE,
225 		.owner = THIS_MODULE,
226 	},
227 };
228 
229 static int wm8400_regulator_probe(struct platform_device *pdev)
230 {
231 	struct wm8400 *wm8400 = container_of(pdev, struct wm8400, regulators[pdev->id]);
232 	struct regulator_config config = { };
233 	struct regulator_dev *rdev;
234 
235 	config.dev = &pdev->dev;
236 	config.init_data = pdev->dev.platform_data;
237 	config.driver_data = wm8400;
238 	config.regmap = wm8400->regmap;
239 
240 	rdev = regulator_register(&regulators[pdev->id], &config);
241 	if (IS_ERR(rdev))
242 		return PTR_ERR(rdev);
243 
244 	platform_set_drvdata(pdev, rdev);
245 
246 	return 0;
247 }
248 
249 static int wm8400_regulator_remove(struct platform_device *pdev)
250 {
251 	struct regulator_dev *rdev = platform_get_drvdata(pdev);
252 
253 	regulator_unregister(rdev);
254 
255 	return 0;
256 }
257 
258 static struct platform_driver wm8400_regulator_driver = {
259 	.driver = {
260 		.name = "wm8400-regulator",
261 	},
262 	.probe = wm8400_regulator_probe,
263 	.remove = wm8400_regulator_remove,
264 };
265 
266 /**
267  * wm8400_register_regulator - enable software control of a WM8400 regulator
268  *
269  * This function enables software control of a WM8400 regulator via
270  * the regulator API.  It is intended to be called from the
271  * platform_init() callback of the WM8400 MFD driver.
272  *
273  * @param dev      The WM8400 device to operate on.
274  * @param reg      The regulator to control.
275  * @param initdata Regulator initdata for the regulator.
276  */
277 int wm8400_register_regulator(struct device *dev, int reg,
278 			      struct regulator_init_data *initdata)
279 {
280 	struct wm8400 *wm8400 = dev_get_drvdata(dev);
281 
282 	if (wm8400->regulators[reg].name)
283 		return -EBUSY;
284 
285 	initdata->driver_data = wm8400;
286 
287 	wm8400->regulators[reg].name = "wm8400-regulator";
288 	wm8400->regulators[reg].id = reg;
289 	wm8400->regulators[reg].dev.parent = dev;
290 	wm8400->regulators[reg].dev.platform_data = initdata;
291 
292 	return platform_device_register(&wm8400->regulators[reg]);
293 }
294 EXPORT_SYMBOL_GPL(wm8400_register_regulator);
295 
296 static int __init wm8400_regulator_init(void)
297 {
298 	return platform_driver_register(&wm8400_regulator_driver);
299 }
300 subsys_initcall(wm8400_regulator_init);
301 
302 static void __exit wm8400_regulator_exit(void)
303 {
304 	platform_driver_unregister(&wm8400_regulator_driver);
305 }
306 module_exit(wm8400_regulator_exit);
307 
308 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
309 MODULE_DESCRIPTION("WM8400 regulator driver");
310 MODULE_LICENSE("GPL");
311 MODULE_ALIAS("platform:wm8400-regulator");
312