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