diff options
Diffstat (limited to 'include/linux/of_gpio.h')
| -rw-r--r-- | include/linux/of_gpio.h | 126 |
1 files changed, 105 insertions, 21 deletions
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h index 67db101d0eb..38fc0503601 100644 --- a/include/linux/of_gpio.h +++ b/include/linux/of_gpio.h @@ -14,56 +14,140 @@ #ifndef __LINUX_OF_GPIO_H #define __LINUX_OF_GPIO_H +#include <linux/compiler.h> +#include <linux/kernel.h> #include <linux/errno.h> #include <linux/gpio.h> +#include <linux/of.h> -#ifdef CONFIG_OF_GPIO +struct device_node; /* - * Generic OF GPIO chip + * This is Linux-specific flags. By default controllers' and Linux' mapping + * match, but GPIO controllers are free to translate their own flags to + * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended. */ -struct of_gpio_chip { - struct gpio_chip gc; - int gpio_cells; - int (*xlate)(struct of_gpio_chip *of_gc, struct device_node *np, - const void *gpio_spec); +enum of_gpio_flags { + OF_GPIO_ACTIVE_LOW = 0x1, }; -static inline struct of_gpio_chip *to_of_gpio_chip(struct gpio_chip *gc) -{ - return container_of(gc, struct of_gpio_chip, gc); -} +#ifdef CONFIG_OF_GPIO /* * OF GPIO chip for memory mapped banks */ struct of_mm_gpio_chip { - struct of_gpio_chip of_gc; + struct gpio_chip gc; void (*save_regs)(struct of_mm_gpio_chip *mm_gc); void __iomem *regs; }; static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc) { - struct of_gpio_chip *of_gc = to_of_gpio_chip(gc); - - return container_of(of_gc, struct of_mm_gpio_chip, of_gc); + return container_of(gc, struct of_mm_gpio_chip, gc); } -extern int of_get_gpio(struct device_node *np, int index); +extern int of_get_named_gpio_flags(struct device_node *np, + const char *list_name, int index, enum of_gpio_flags *flags); + extern int of_mm_gpiochip_add(struct device_node *np, struct of_mm_gpio_chip *mm_gc); -extern int of_gpio_simple_xlate(struct of_gpio_chip *of_gc, - struct device_node *np, - const void *gpio_spec); -#else + +extern void of_gpiochip_add(struct gpio_chip *gc); +extern void of_gpiochip_remove(struct gpio_chip *gc); +extern int of_gpio_simple_xlate(struct gpio_chip *gc, + const struct of_phandle_args *gpiospec, + u32 *flags); + +#else /* CONFIG_OF_GPIO */ /* Drivers may not strictly depend on the GPIO support, so let them link. */ -static inline int of_get_gpio(struct device_node *np, int index) +static inline int of_get_named_gpio_flags(struct device_node *np, + const char *list_name, int index, enum of_gpio_flags *flags) { return -ENOSYS; } +static inline int of_gpio_simple_xlate(struct gpio_chip *gc, + const struct of_phandle_args *gpiospec, + u32 *flags) +{ + return -ENOSYS; +} + +static inline void of_gpiochip_add(struct gpio_chip *gc) { } +static inline void of_gpiochip_remove(struct gpio_chip *gc) { } + #endif /* CONFIG_OF_GPIO */ +/** + * of_gpio_named_count() - Count GPIOs for a device + * @np: device node to count GPIOs for + * @propname: property name containing gpio specifier(s) + * + * The function returns the count of GPIOs specified for a node. + * Note that the empty GPIO specifiers count too. Returns either + * Number of gpios defined in property, + * -EINVAL for an incorrectly formed gpios property, or + * -ENOENT for a missing gpios property + * + * Example: + * gpios = <0 + * &gpio1 1 2 + * 0 + * &gpio2 3 4>; + * + * The above example defines four GPIOs, two of which are not specified. + * This function will return '4' + */ +static inline int of_gpio_named_count(struct device_node *np, const char* propname) +{ + return of_count_phandle_with_args(np, propname, "#gpio-cells"); +} + +/** + * of_gpio_count() - Count GPIOs for a device + * @np: device node to count GPIOs for + * + * Same as of_gpio_named_count, but hard coded to use the 'gpios' property + */ +static inline int of_gpio_count(struct device_node *np) +{ + return of_gpio_named_count(np, "gpios"); +} + +static inline int of_get_gpio_flags(struct device_node *np, int index, + enum of_gpio_flags *flags) +{ + return of_get_named_gpio_flags(np, "gpios", index, flags); +} + +/** + * of_get_named_gpio() - Get a GPIO number to use with GPIO API + * @np: device node to get GPIO from + * @propname: Name of property containing gpio specifier(s) + * @index: index of the GPIO + * + * Returns GPIO number to use with Linux generic GPIO API, or one of the errno + * value on the error condition. + */ +static inline int of_get_named_gpio(struct device_node *np, + const char *propname, int index) +{ + return of_get_named_gpio_flags(np, propname, index, NULL); +} + +/** + * of_get_gpio() - Get a GPIO number to use with GPIO API + * @np: device node to get GPIO from + * @index: index of the GPIO + * + * Returns GPIO number to use with Linux generic GPIO API, or one of the errno + * value on the error condition. + */ +static inline int of_get_gpio(struct device_node *np, int index) +{ + return of_get_gpio_flags(np, index, NULL); +} + #endif /* __LINUX_OF_GPIO_H */ |
