2 * OF helpers for the GPIO API
4 * Copyright (c) 2007-2008 MontaVista Software, Inc.
6 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
14 #ifndef __LINUX_OF_GPIO_H
15 #define __LINUX_OF_GPIO_H
17 #include <linux/compiler.h>
18 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/gpio.h>
26 * This is Linux-specific flags. By default controllers' and Linux' mapping
27 * match, but GPIO controllers are free to translate their own flags to
28 * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
31 OF_GPIO_ACTIVE_LOW
= 0x1,
32 OF_GPIO_SINGLE_ENDED
= 0x2,
38 * OF GPIO chip for memory mapped banks
40 struct of_mm_gpio_chip
{
42 void (*save_regs
)(struct of_mm_gpio_chip
*mm_gc
);
46 static inline struct of_mm_gpio_chip
*to_of_mm_gpio_chip(struct gpio_chip
*gc
)
48 return container_of(gc
, struct of_mm_gpio_chip
, gc
);
51 extern int of_get_named_gpio_flags(struct device_node
*np
,
52 const char *list_name
, int index
, enum of_gpio_flags
*flags
);
54 extern int of_mm_gpiochip_add(struct device_node
*np
,
55 struct of_mm_gpio_chip
*mm_gc
);
56 extern void of_mm_gpiochip_remove(struct of_mm_gpio_chip
*mm_gc
);
58 extern int of_gpiochip_add(struct gpio_chip
*gc
);
59 extern void of_gpiochip_remove(struct gpio_chip
*gc
);
60 extern int of_gpio_simple_xlate(struct gpio_chip
*gc
,
61 const struct of_phandle_args
*gpiospec
,
64 #else /* CONFIG_OF_GPIO */
66 /* Drivers may not strictly depend on the GPIO support, so let them link. */
67 static inline int of_get_named_gpio_flags(struct device_node
*np
,
68 const char *list_name
, int index
, enum of_gpio_flags
*flags
)
73 static inline int of_gpio_simple_xlate(struct gpio_chip
*gc
,
74 const struct of_phandle_args
*gpiospec
,
80 static inline int of_gpiochip_add(struct gpio_chip
*gc
) { return 0; }
81 static inline void of_gpiochip_remove(struct gpio_chip
*gc
) { }
83 #endif /* CONFIG_OF_GPIO */
86 * of_gpio_named_count() - Count GPIOs for a device
87 * @np: device node to count GPIOs for
88 * @propname: property name containing gpio specifier(s)
90 * The function returns the count of GPIOs specified for a node.
91 * Note that the empty GPIO specifiers count too. Returns either
92 * Number of gpios defined in property,
93 * -EINVAL for an incorrectly formed gpios property, or
94 * -ENOENT for a missing gpios property
102 * The above example defines four GPIOs, two of which are not specified.
103 * This function will return '4'
105 static inline int of_gpio_named_count(struct device_node
*np
, const char* propname
)
107 return of_count_phandle_with_args(np
, propname
, "#gpio-cells");
111 * of_gpio_count() - Count GPIOs for a device
112 * @np: device node to count GPIOs for
114 * Same as of_gpio_named_count, but hard coded to use the 'gpios' property
116 static inline int of_gpio_count(struct device_node
*np
)
118 return of_gpio_named_count(np
, "gpios");
121 static inline int of_get_gpio_flags(struct device_node
*np
, int index
,
122 enum of_gpio_flags
*flags
)
124 return of_get_named_gpio_flags(np
, "gpios", index
, flags
);
128 * of_get_named_gpio() - Get a GPIO number to use with GPIO API
129 * @np: device node to get GPIO from
130 * @propname: Name of property containing gpio specifier(s)
131 * @index: index of the GPIO
133 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
134 * value on the error condition.
136 static inline int of_get_named_gpio(struct device_node
*np
,
137 const char *propname
, int index
)
139 return of_get_named_gpio_flags(np
, propname
, index
, NULL
);
143 * of_get_gpio() - Get a GPIO number to use with GPIO API
144 * @np: device node to get GPIO from
145 * @index: index of the GPIO
147 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
148 * value on the error condition.
150 static inline int of_get_gpio(struct device_node
*np
, int index
)
152 return of_get_gpio_flags(np
, index
, NULL
);
155 #endif /* __LINUX_OF_GPIO_H */
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