xref: /linux/drivers/regulator/of_regulator.c (revision 068df0f34e81bc06c5eb5012ec2eda25624e87aa)
1 /*
2  * OF helpers for regulator framework
3  *
4  * Copyright (C) 2011 Texas Instruments, Inc.
5  * Rajendra Nayak <rnayak@ti.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 as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/of.h>
16 #include <linux/regulator/machine.h>
17 
18 static void of_get_regulation_constraints(struct device_node *np,
19 					struct regulator_init_data **init_data)
20 {
21 	const __be32 *min_uV, *max_uV, *uV_offset;
22 	const __be32 *min_uA, *max_uA;
23 	struct regulation_constraints *constraints = &(*init_data)->constraints;
24 
25 	constraints->name = of_get_property(np, "regulator-name", NULL);
26 
27 	min_uV = of_get_property(np, "regulator-min-microvolt", NULL);
28 	if (min_uV)
29 		constraints->min_uV = be32_to_cpu(*min_uV);
30 	max_uV = of_get_property(np, "regulator-max-microvolt", NULL);
31 	if (max_uV)
32 		constraints->max_uV = be32_to_cpu(*max_uV);
33 
34 	/* Voltage change possible? */
35 	if (constraints->min_uV != constraints->max_uV)
36 		constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
37 
38 	uV_offset = of_get_property(np, "regulator-microvolt-offset", NULL);
39 	if (uV_offset)
40 		constraints->uV_offset = be32_to_cpu(*uV_offset);
41 	min_uA = of_get_property(np, "regulator-min-microamp", NULL);
42 	if (min_uA)
43 		constraints->min_uA = be32_to_cpu(*min_uA);
44 	max_uA = of_get_property(np, "regulator-max-microamp", NULL);
45 	if (max_uA)
46 		constraints->max_uA = be32_to_cpu(*max_uA);
47 
48 	/* Current change possible? */
49 	if (constraints->min_uA != constraints->max_uA)
50 		constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
51 
52 	if (of_find_property(np, "regulator-boot-on", NULL))
53 		constraints->boot_on = true;
54 
55 	if (of_find_property(np, "regulator-always-on", NULL))
56 		constraints->always_on = true;
57 	else /* status change should be possible if not always on. */
58 		constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
59 }
60 
61 /**
62  * of_get_regulator_init_data - extract regulator_init_data structure info
63  * @dev: device requesting for regulator_init_data
64  *
65  * Populates regulator_init_data structure by extracting data from device
66  * tree node, returns a pointer to the populated struture or NULL if memory
67  * alloc fails.
68  */
69 struct regulator_init_data *of_get_regulator_init_data(struct device *dev)
70 {
71 	struct regulator_init_data *init_data;
72 
73 	if (!dev->of_node)
74 		return NULL;
75 
76 	init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
77 	if (!init_data)
78 		return NULL; /* Out of memory? */
79 
80 	of_get_regulation_constraints(dev->of_node, &init_data);
81 	return init_data;
82 }
83 EXPORT_SYMBOL_GPL(of_get_regulator_init_data);
84