aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/base/property.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/base/property.c')
-rw-r--r--drivers/base/property.c185
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/base/property.c b/drivers/base/property.c
new file mode 100644
index 000000000000..6a94ef6e83c9
--- /dev/null
+++ b/drivers/base/property.c
@@ -0,0 +1,185 @@
1/*
2 * property.c - Unified device property interface.
3 *
4 * Copyright (C) 2014, Intel Corporation
5 * Authors: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6 * Mika Westerberg <mika.westerberg@linux.intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/property.h>
14#include <linux/export.h>
15#include <linux/acpi.h>
16#include <linux/of.h>
17
18/**
19 * device_property_present - check if a property of a device is present
20 * @dev: Device whose property is being checked
21 * @propname: Name of the property
22 *
23 * Check if property @propname is present in the device firmware description.
24 */
25bool device_property_present(struct device *dev, const char *propname)
26{
27 if (IS_ENABLED(CONFIG_OF) && dev->of_node)
28 return of_property_read_bool(dev->of_node, propname);
29
30 return !acpi_dev_prop_get(ACPI_COMPANION(dev), propname, NULL);
31}
32EXPORT_SYMBOL_GPL(device_property_present);
33
34#define OF_DEV_PROP_READ_ARRAY(node, propname, type, val, nval) \
35 (val) ? of_property_read_##type##_array((node), (propname), (val), (nval)) \
36 : of_property_count_elems_of_size((node), (propname), sizeof(type))
37
38#define DEV_PROP_READ_ARRAY(_dev_, _propname_, _type_, _proptype_, _val_, _nval_) \
39 IS_ENABLED(CONFIG_OF) && _dev_->of_node ? \
40 (OF_DEV_PROP_READ_ARRAY(_dev_->of_node, _propname_, _type_, \
41 _val_, _nval_)) : \
42 acpi_dev_prop_read(ACPI_COMPANION(_dev_), _propname_, \
43 _proptype_, _val_, _nval_)
44
45/**
46 * device_property_read_u8_array - return a u8 array property of a device
47 * @dev: Device to get the property of
48 * @propname: Name of the property
49 * @val: The values are stored here
50 * @nval: Size of the @val array
51 *
52 * Function reads an array of u8 properties with @propname from the device
53 * firmware description and stores them to @val if found.
54 *
55 * Return: %0 if the property was found (success),
56 * %-EINVAL if given arguments are not valid,
57 * %-ENODATA if the property does not have a value,
58 * %-EPROTO if the property is not an array of numbers,
59 * %-EOVERFLOW if the size of the property is not as expected.
60 */
61int device_property_read_u8_array(struct device *dev, const char *propname,
62 u8 *val, size_t nval)
63{
64 return DEV_PROP_READ_ARRAY(dev, propname, u8, DEV_PROP_U8, val, nval);
65}
66EXPORT_SYMBOL_GPL(device_property_read_u8_array);
67
68/**
69 * device_property_read_u16_array - return a u16 array property of a device
70 * @dev: Device to get the property of
71 * @propname: Name of the property
72 * @val: The values are stored here
73 * @nval: Size of the @val array
74 *
75 * Function reads an array of u16 properties with @propname from the device
76 * firmware description and stores them to @val if found.
77 *
78 * Return: %0 if the property was found (success),
79 * %-EINVAL if given arguments are not valid,
80 * %-ENODATA if the property does not have a value,
81 * %-EPROTO if the property is not an array of numbers,
82 * %-EOVERFLOW if the size of the property is not as expected.
83 */
84int device_property_read_u16_array(struct device *dev, const char *propname,
85 u16 *val, size_t nval)
86{
87 return DEV_PROP_READ_ARRAY(dev, propname, u16, DEV_PROP_U16, val, nval);
88}
89EXPORT_SYMBOL_GPL(device_property_read_u16_array);
90
91/**
92 * device_property_read_u32_array - return a u32 array property of a device
93 * @dev: Device to get the property of
94 * @propname: Name of the property
95 * @val: The values are stored here
96 * @nval: Size of the @val array
97 *
98 * Function reads an array of u32 properties with @propname from the device
99 * firmware description and stores them to @val if found.
100 *
101 * Return: %0 if the property was found (success),
102 * %-EINVAL if given arguments are not valid,
103 * %-ENODATA if the property does not have a value,
104 * %-EPROTO if the property is not an array of numbers,
105 * %-EOVERFLOW if the size of the property is not as expected.
106 */
107int device_property_read_u32_array(struct device *dev, const char *propname,
108 u32 *val, size_t nval)
109{
110 return DEV_PROP_READ_ARRAY(dev, propname, u32, DEV_PROP_U32, val, nval);
111}
112EXPORT_SYMBOL_GPL(device_property_read_u32_array);
113
114/**
115 * device_property_read_u64_array - return a u64 array property of a device
116 * @dev: Device to get the property of
117 * @propname: Name of the property
118 * @val: The values are stored here
119 * @nval: Size of the @val array
120 *
121 * Function reads an array of u64 properties with @propname from the device
122 * firmware description and stores them to @val if found.
123 *
124 * Return: %0 if the property was found (success),
125 * %-EINVAL if given arguments are not valid,
126 * %-ENODATA if the property does not have a value,
127 * %-EPROTO if the property is not an array of numbers,
128 * %-EOVERFLOW if the size of the property is not as expected.
129 */
130int device_property_read_u64_array(struct device *dev, const char *propname,
131 u64 *val, size_t nval)
132{
133 return DEV_PROP_READ_ARRAY(dev, propname, u64, DEV_PROP_U64, val, nval);
134}
135EXPORT_SYMBOL_GPL(device_property_read_u64_array);
136
137/**
138 * device_property_read_string_array - return a string array property of device
139 * @dev: Device to get the property of
140 * @propname: Name of the property
141 * @val: The values are stored here
142 * @nval: Size of the @val array
143 *
144 * Function reads an array of string properties with @propname from the device
145 * firmware description and stores them to @val if found.
146 *
147 * Return: %0 if the property was found (success),
148 * %-EINVAL if given arguments are not valid,
149 * %-ENODATA if the property does not have a value,
150 * %-EPROTO or %-EILSEQ if the property is not an array of strings,
151 * %-EOVERFLOW if the size of the property is not as expected.
152 */
153int device_property_read_string_array(struct device *dev, const char *propname,
154 const char **val, size_t nval)
155{
156 return IS_ENABLED(CONFIG_OF) && dev->of_node ?
157 of_property_read_string_array(dev->of_node, propname, val, nval) :
158 acpi_dev_prop_read(ACPI_COMPANION(dev), propname,
159 DEV_PROP_STRING, val, nval);
160}
161EXPORT_SYMBOL_GPL(device_property_read_string_array);
162
163/**
164 * device_property_read_string - return a string property of a device
165 * @dev: Device to get the property of
166 * @propname: Name of the property
167 * @val: The value is stored here
168 *
169 * Function reads property @propname from the device firmware description and
170 * stores the value into @val if found. The value is checked to be a string.
171 *
172 * Return: %0 if the property was found (success),
173 * %-EINVAL if given arguments are not valid,
174 * %-ENODATA if the property does not have a value,
175 * %-EPROTO or %-EILSEQ if the property type is not a string.
176 */
177int device_property_read_string(struct device *dev, const char *propname,
178 const char **val)
179{
180 return IS_ENABLED(CONFIG_OF) && dev->of_node ?
181 of_property_read_string(dev->of_node, propname, val) :
182 acpi_dev_prop_read(ACPI_COMPANION(dev), propname,
183 DEV_PROP_STRING, val, 1);
184}
185EXPORT_SYMBOL_GPL(device_property_read_string);
generated by cgit v1.2.2 (git 2.25.0) at 2025-09-19 14:41:23 -0400