diff options
Diffstat (limited to 'include/asm-generic/gpio.h')
| -rw-r--r-- | include/asm-generic/gpio.h | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index 4f3d75e1ad39..8ca18e26d7e3 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -16,21 +16,34 @@ * While the GPIO programming interface defines valid GPIO numbers * to be in the range 0..MAX_INT, this library restricts them to the * smaller range 0..ARCH_NR_GPIOS-1. + * + * ARCH_NR_GPIOS is somewhat arbitrary; it usually reflects the sum of + * builtin/SoC GPIOs plus a number of GPIOs on expanders; the latter is + * actually an estimate of a board-specific value. */ #ifndef ARCH_NR_GPIOS #define ARCH_NR_GPIOS 256 #endif +/* + * "valid" GPIO numbers are nonnegative and may be passed to + * setup routines like gpio_request(). only some valid numbers + * can successfully be requested and used. + * + * Invalid GPIO numbers are useful for indicating no-such-GPIO in + * platform data and other tables. + */ + static inline int gpio_is_valid(int number) { - /* only some non-negative numbers are valid */ return ((unsigned)number) < ARCH_NR_GPIOS; } struct device; struct seq_file; struct module; +struct device_node; /** * struct gpio_chip - abstract a GPIO controller @@ -106,6 +119,17 @@ struct gpio_chip { const char *const *names; unsigned can_sleep:1; unsigned exported:1; + +#if defined(CONFIG_OF_GPIO) + /* + * If CONFIG_OF is enabled, then all GPIO controllers described in the + * device tree automatically may have an OF translation + */ + struct device_node *of_node; + int of_gpio_n_cells; + int (*of_xlate)(struct gpio_chip *gc, struct device_node *np, + const void *gpio_spec, u32 *flags); +#endif }; extern const char *gpiochip_is_requested(struct gpio_chip *chip, @@ -115,6 +139,9 @@ extern int __must_check gpiochip_reserve(int start, int ngpio); /* add/remove chips */ extern int gpiochip_add(struct gpio_chip *chip); extern int __must_check gpiochip_remove(struct gpio_chip *chip); +extern struct gpio_chip *gpiochip_find(void *data, + int (*match)(struct gpio_chip *chip, + void *data)); /* Always use the library code for GPIO management calls, |
