1 /*
2  * Regulators driver for Maxim max8925
3  *
4  * Copyright (C) 2009 Marvell International Ltd.
5  *      Haojian Zhuang <haojian.zhuang@marvell.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/err.h>
15 #include <linux/i2c.h>
16 #include <linux/platform_device.h>
17 #include <linux/regulator/driver.h>
18 #include <linux/regulator/machine.h>
19 #include <linux/mfd/max8925.h>
20 #include <linux/of.h>
21 #include <linux/regulator/of_regulator.h>
22 
23 #define SD1_DVM_VMIN		850000
24 #define SD1_DVM_VMAX		1000000
25 #define SD1_DVM_STEP		50000
26 #define SD1_DVM_SHIFT		5		/* SDCTL1 bit5 */
27 #define SD1_DVM_EN		6		/* SDV1 bit 6 */
28 
29 /* bit definitions in LDO control registers */
30 #define LDO_SEQ_I2C		0x7		/* Power U/D by i2c */
31 #define LDO_SEQ_MASK		0x7		/* Power U/D sequence mask */
32 #define LDO_SEQ_SHIFT		2		/* Power U/D sequence offset */
33 #define LDO_I2C_EN		0x1		/* Enable by i2c */
34 #define LDO_I2C_EN_MASK		0x1		/* Enable mask by i2c */
35 #define LDO_I2C_EN_SHIFT	0		/* Enable offset by i2c */
36 
37 struct max8925_regulator_info {
38 	struct regulator_desc	desc;
39 	struct regulator_dev	*regulator;
40 	struct i2c_client	*i2c;
41 	struct max8925_chip	*chip;
42 
43 	int	vol_reg;
44 	int	enable_reg;
45 };
46 
47 static int max8925_set_voltage_sel(struct regulator_dev *rdev,
48 				   unsigned int selector)
49 {
50 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
51 	unsigned char mask = rdev->desc->n_voltages - 1;
52 
53 	return max8925_set_bits(info->i2c, info->vol_reg, mask, selector);
54 }
55 
56 static int max8925_get_voltage_sel(struct regulator_dev *rdev)
57 {
58 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
59 	unsigned char data, mask;
60 	int ret;
61 
62 	ret = max8925_reg_read(info->i2c, info->vol_reg);
63 	if (ret < 0)
64 		return ret;
65 	mask = rdev->desc->n_voltages - 1;
66 	data = ret & mask;
67 
68 	return data;
69 }
70 
71 static int max8925_enable(struct regulator_dev *rdev)
72 {
73 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
74 
75 	return max8925_set_bits(info->i2c, info->enable_reg,
76 				LDO_SEQ_MASK << LDO_SEQ_SHIFT |
77 				LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT,
78 				LDO_SEQ_I2C << LDO_SEQ_SHIFT |
79 				LDO_I2C_EN << LDO_I2C_EN_SHIFT);
80 }
81 
82 static int max8925_disable(struct regulator_dev *rdev)
83 {
84 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
85 
86 	return max8925_set_bits(info->i2c, info->enable_reg,
87 				LDO_SEQ_MASK << LDO_SEQ_SHIFT |
88 				LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT,
89 				LDO_SEQ_I2C << LDO_SEQ_SHIFT);
90 }
91 
92 static int max8925_is_enabled(struct regulator_dev *rdev)
93 {
94 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
95 	int ldo_seq, ret;
96 
97 	ret = max8925_reg_read(info->i2c, info->enable_reg);
98 	if (ret < 0)
99 		return ret;
100 	ldo_seq = (ret >> LDO_SEQ_SHIFT) & LDO_SEQ_MASK;
101 	if (ldo_seq != LDO_SEQ_I2C)
102 		return 1;
103 	else
104 		return ret & (LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT);
105 }
106 
107 static int max8925_set_dvm_voltage(struct regulator_dev *rdev, int uV)
108 {
109 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
110 	unsigned char data, mask;
111 
112 	if (uV < SD1_DVM_VMIN || uV > SD1_DVM_VMAX)
113 		return -EINVAL;
114 
115 	data = DIV_ROUND_UP(uV - SD1_DVM_VMIN, SD1_DVM_STEP);
116 	data <<= SD1_DVM_SHIFT;
117 	mask = 3 << SD1_DVM_SHIFT;
118 
119 	return max8925_set_bits(info->i2c, info->enable_reg, mask, data);
120 }
121 
122 static int max8925_set_dvm_enable(struct regulator_dev *rdev)
123 {
124 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
125 
126 	return max8925_set_bits(info->i2c, info->vol_reg, 1 << SD1_DVM_EN,
127 				1 << SD1_DVM_EN);
128 }
129 
130 static int max8925_set_dvm_disable(struct regulator_dev *rdev)
131 {
132 	struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
133 
134 	return max8925_set_bits(info->i2c, info->vol_reg, 1 << SD1_DVM_EN, 0);
135 }
136 
137 static struct regulator_ops max8925_regulator_sdv_ops = {
138 	.map_voltage		= regulator_map_voltage_linear,
139 	.list_voltage		= regulator_list_voltage_linear,
140 	.set_voltage_sel	= max8925_set_voltage_sel,
141 	.get_voltage_sel	= max8925_get_voltage_sel,
142 	.enable			= max8925_enable,
143 	.disable		= max8925_disable,
144 	.is_enabled		= max8925_is_enabled,
145 	.set_suspend_voltage	= max8925_set_dvm_voltage,
146 	.set_suspend_enable	= max8925_set_dvm_enable,
147 	.set_suspend_disable	= max8925_set_dvm_disable,
148 };
149 
150 static struct regulator_ops max8925_regulator_ldo_ops = {
151 	.map_voltage		= regulator_map_voltage_linear,
152 	.list_voltage		= regulator_list_voltage_linear,
153 	.set_voltage_sel	= max8925_set_voltage_sel,
154 	.get_voltage_sel	= max8925_get_voltage_sel,
155 	.enable			= max8925_enable,
156 	.disable		= max8925_disable,
157 	.is_enabled		= max8925_is_enabled,
158 };
159 
160 #define MAX8925_SDV(_id, min, max, step)			\
161 {								\
162 	.desc	= {						\
163 		.name	= "SDV" #_id,				\
164 		.ops	= &max8925_regulator_sdv_ops,		\
165 		.type	= REGULATOR_VOLTAGE,			\
166 		.id	= MAX8925_ID_SD##_id,			\
167 		.owner	= THIS_MODULE,				\
168 		.n_voltages = 64,				\
169 		.min_uV = min * 1000,				\
170 		.uV_step = step * 1000,				\
171 	},							\
172 	.vol_reg	= MAX8925_SDV##_id,			\
173 	.enable_reg	= MAX8925_SDCTL##_id,			\
174 }
175 
176 #define MAX8925_LDO(_id, min, max, step)			\
177 {								\
178 	.desc	= {						\
179 		.name	= "LDO" #_id,				\
180 		.ops	= &max8925_regulator_ldo_ops,		\
181 		.type	= REGULATOR_VOLTAGE,			\
182 		.id	= MAX8925_ID_LDO##_id,			\
183 		.owner	= THIS_MODULE,				\
184 		.n_voltages = 64,				\
185 		.min_uV = min * 1000,				\
186 		.uV_step = step * 1000,				\
187 	},							\
188 	.vol_reg	= MAX8925_LDOVOUT##_id,			\
189 	.enable_reg	= MAX8925_LDOCTL##_id,			\
190 }
191 
192 #ifdef CONFIG_OF
193 static struct of_regulator_match max8925_regulator_matches[] = {
194 	{ .name	= "SDV1",},
195 	{ .name = "SDV2",},
196 	{ .name = "SDV3",},
197 	{ .name = "LDO1",},
198 	{ .name = "LDO2",},
199 	{ .name = "LDO3",},
200 	{ .name = "LDO4",},
201 	{ .name = "LDO5",},
202 	{ .name = "LDO6",},
203 	{ .name = "LDO7",},
204 	{ .name = "LDO8",},
205 	{ .name = "LDO9",},
206 	{ .name = "LDO10",},
207 	{ .name = "LDO11",},
208 	{ .name = "LDO12",},
209 	{ .name = "LDO13",},
210 	{ .name = "LDO14",},
211 	{ .name = "LDO15",},
212 	{ .name = "LDO16",},
213 	{ .name = "LDO17",},
214 	{ .name = "LDO18",},
215 	{ .name = "LDO19",},
216 	{ .name = "LDO20",},
217 };
218 #endif
219 
220 static struct max8925_regulator_info max8925_regulator_info[] = {
221 	MAX8925_SDV(1, 637.5, 1425, 12.5),
222 	MAX8925_SDV(2,   650, 2225,   25),
223 	MAX8925_SDV(3,   750, 3900,   50),
224 
225 	MAX8925_LDO(1,  750, 3900, 50),
226 	MAX8925_LDO(2,  650, 2250, 25),
227 	MAX8925_LDO(3,  650, 2250, 25),
228 	MAX8925_LDO(4,  750, 3900, 50),
229 	MAX8925_LDO(5,  750, 3900, 50),
230 	MAX8925_LDO(6,  750, 3900, 50),
231 	MAX8925_LDO(7,  750, 3900, 50),
232 	MAX8925_LDO(8,  750, 3900, 50),
233 	MAX8925_LDO(9,  750, 3900, 50),
234 	MAX8925_LDO(10, 750, 3900, 50),
235 	MAX8925_LDO(11, 750, 3900, 50),
236 	MAX8925_LDO(12, 750, 3900, 50),
237 	MAX8925_LDO(13, 750, 3900, 50),
238 	MAX8925_LDO(14, 750, 3900, 50),
239 	MAX8925_LDO(15, 750, 3900, 50),
240 	MAX8925_LDO(16, 750, 3900, 50),
241 	MAX8925_LDO(17, 650, 2250, 25),
242 	MAX8925_LDO(18, 650, 2250, 25),
243 	MAX8925_LDO(19, 750, 3900, 50),
244 	MAX8925_LDO(20, 750, 3900, 50),
245 };
246 
247 #ifdef CONFIG_OF
248 static int max8925_regulator_dt_init(struct platform_device *pdev,
249 				    struct regulator_config *config,
250 				    int ridx)
251 {
252 	struct device_node *nproot, *np;
253 	int rcount;
254 	nproot = of_node_get(pdev->dev.parent->of_node);
255 	if (!nproot)
256 		return -ENODEV;
257 	np = of_find_node_by_name(nproot, "regulators");
258 	if (!np) {
259 		dev_err(&pdev->dev, "failed to find regulators node\n");
260 		return -ENODEV;
261 	}
262 
263 	rcount = of_regulator_match(&pdev->dev, np,
264 				&max8925_regulator_matches[ridx], 1);
265 	of_node_put(np);
266 	if (rcount < 0)
267 		return -ENODEV;
268 	config->init_data =	max8925_regulator_matches[ridx].init_data;
269 	config->of_node = max8925_regulator_matches[ridx].of_node;
270 
271 	return 0;
272 }
273 #else
274 #define max8925_regulator_dt_init(x, y, z)	(-1)
275 #endif
276 
277 static int max8925_regulator_probe(struct platform_device *pdev)
278 {
279 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
280 	struct regulator_init_data *pdata = dev_get_platdata(&pdev->dev);
281 	struct regulator_config config = { };
282 	struct max8925_regulator_info *ri;
283 	struct resource *res;
284 	struct regulator_dev *rdev;
285 	int i, regulator_idx;
286 
287 	res = platform_get_resource(pdev, IORESOURCE_REG, 0);
288 	if (!res) {
289 		dev_err(&pdev->dev, "No REG resource!\n");
290 		return -EINVAL;
291 	}
292 	for (i = 0; i < ARRAY_SIZE(max8925_regulator_info); i++) {
293 		ri = &max8925_regulator_info[i];
294 		if (ri->vol_reg == res->start) {
295 			regulator_idx = i;
296 			break;
297 		}
298 	}
299 
300 	if (i == ARRAY_SIZE(max8925_regulator_info)) {
301 		dev_err(&pdev->dev, "Failed to find regulator %llu\n",
302 			(unsigned long long)res->start);
303 		return -EINVAL;
304 	}
305 	ri->i2c = chip->i2c;
306 	ri->chip = chip;
307 
308 	config.dev = &pdev->dev;
309 	config.driver_data = ri;
310 
311 	if (max8925_regulator_dt_init(pdev, &config, regulator_idx))
312 		if (pdata)
313 			config.init_data = pdata;
314 
315 	rdev = regulator_register(&ri->desc, &config);
316 	if (IS_ERR(rdev)) {
317 		dev_err(&pdev->dev, "failed to register regulator %s\n",
318 				ri->desc.name);
319 		return PTR_ERR(rdev);
320 	}
321 
322 	platform_set_drvdata(pdev, rdev);
323 	return 0;
324 }
325 
326 static int max8925_regulator_remove(struct platform_device *pdev)
327 {
328 	struct regulator_dev *rdev = platform_get_drvdata(pdev);
329 
330 	regulator_unregister(rdev);
331 
332 	return 0;
333 }
334 
335 static struct platform_driver max8925_regulator_driver = {
336 	.driver		= {
337 		.name	= "max8925-regulator",
338 		.owner	= THIS_MODULE,
339 	},
340 	.probe		= max8925_regulator_probe,
341 	.remove		= max8925_regulator_remove,
342 };
343 
344 static int __init max8925_regulator_init(void)
345 {
346 	return platform_driver_register(&max8925_regulator_driver);
347 }
348 subsys_initcall(max8925_regulator_init);
349 
350 static void __exit max8925_regulator_exit(void)
351 {
352 	platform_driver_unregister(&max8925_regulator_driver);
353 }
354 module_exit(max8925_regulator_exit);
355 
356 MODULE_LICENSE("GPL");
357 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
358 MODULE_DESCRIPTION("Regulator Driver for Maxim 8925 PMIC");
359 MODULE_ALIAS("platform:max8925-regulator");
360