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>
22 #include <linux/gpio/consumer.h>
27 * This is Linux-specific flags. By default controllers' and Linux' mapping
28 * match, but GPIO controllers are free to translate their own flags to
29 * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
32 OF_GPIO_ACTIVE_LOW
= 0x1,
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 struct gpio_desc
*of_get_named_gpiod_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
);
57 extern void of_gpiochip_add(struct gpio_chip
*gc
);
58 extern void of_gpiochip_remove(struct gpio_chip
*gc
);
59 extern int of_gpio_simple_xlate(struct gpio_chip
*gc
,
60 const struct of_phandle_args
*gpiospec
,
63 #else /* CONFIG_OF_GPIO */
65 /* Drivers may not strictly depend on the GPIO support, so let them link. */
66 static inline struct gpio_desc
*of_get_named_gpiod_flags(struct device_node
*np
,
67 const char *list_name
, int index
, enum of_gpio_flags
*flags
)
69 return ERR_PTR(-ENOSYS
);
72 static inline int of_gpio_simple_xlate(struct gpio_chip
*gc
,
73 const struct of_phandle_args
*gpiospec
,
79 static inline void of_gpiochip_add(struct gpio_chip
*gc
) { }
80 static inline void of_gpiochip_remove(struct gpio_chip
*gc
) { }
82 #endif /* CONFIG_OF_GPIO */
84 static inline int of_get_named_gpio_flags(struct device_node
*np
,
85 const char *list_name
, int index
, enum of_gpio_flags
*flags
)
87 struct gpio_desc
*desc
;
88 desc
= of_get_named_gpiod_flags(np
, list_name
, index
, flags
);
93 return desc_to_gpio(desc
);
97 * of_gpio_named_count() - Count GPIOs for a device
98 * @np: device node to count GPIOs for
99 * @propname: property name containing gpio specifier(s)
101 * The function returns the count of GPIOs specified for a node.
102 * Note that the empty GPIO specifiers count too. Returns either
103 * Number of gpios defined in property,
104 * -EINVAL for an incorrectly formed gpios property, or
105 * -ENOENT for a missing gpios property
113 * The above example defines four GPIOs, two of which are not specified.
114 * This function will return '4'
116 static inline int of_gpio_named_count(struct device_node
*np
, const char* propname
)
118 return of_count_phandle_with_args(np
, propname
, "#gpio-cells");
122 * of_gpio_count() - Count GPIOs for a device
123 * @np: device node to count GPIOs for
125 * Same as of_gpio_named_count, but hard coded to use the 'gpios' property
127 static inline int of_gpio_count(struct device_node
*np
)
129 return of_gpio_named_count(np
, "gpios");
133 * of_get_gpiod_flags() - Get a GPIO descriptor and flags to use with GPIO API
134 * @np: device node to get GPIO from
135 * @index: index of the GPIO
136 * @flags: a flags pointer to fill in
138 * Returns GPIO descriptor to use with Linux generic GPIO API, or a errno
139 * value on the error condition. If @flags is not NULL the function also fills
140 * in flags for the GPIO.
142 static inline struct gpio_desc
*of_get_gpiod_flags(struct device_node
*np
,
143 int index
, enum of_gpio_flags
*flags
)
145 return of_get_named_gpiod_flags(np
, "gpios", index
, flags
);
148 static inline int of_get_gpio_flags(struct device_node
*np
, int index
,
149 enum of_gpio_flags
*flags
)
151 return of_get_named_gpio_flags(np
, "gpios", index
, flags
);
155 * of_get_named_gpio() - Get a GPIO number to use with GPIO API
156 * @np: device node to get GPIO from
157 * @propname: Name of property containing gpio specifier(s)
158 * @index: index of the GPIO
160 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
161 * value on the error condition.
163 static inline int of_get_named_gpio(struct device_node
*np
,
164 const char *propname
, int index
)
166 return of_get_named_gpio_flags(np
, propname
, index
, NULL
);
170 * of_get_gpio() - Get a GPIO number to use with GPIO API
171 * @np: device node to get GPIO from
172 * @index: index of the GPIO
174 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
175 * value on the error condition.
177 static inline int of_get_gpio(struct device_node
*np
, int index
)
179 return of_get_gpio_flags(np
, index
, NULL
);
182 #endif /* __LINUX_OF_GPIO_H */
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