diff options
| -rw-r--r-- | arch/arm/include/asm/gpio.h | 1 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib.c | 10 | ||||
| -rw-r--r-- | include/asm-generic/gpio.h | 55 |
3 files changed, 26 insertions, 40 deletions
diff --git a/arch/arm/include/asm/gpio.h b/arch/arm/include/asm/gpio.h index f3bb8a2bf788..4ebbb58f06ea 100644 --- a/arch/arm/include/asm/gpio.h +++ b/arch/arm/include/asm/gpio.h @@ -2,7 +2,6 @@ #ifndef _ARCH_ARM_GPIO_H #define _ARCH_ARM_GPIO_H -/* Note: this may rely upon the value of ARCH_NR_GPIOS set in mach/gpio.h */ #include <asm-generic/gpio.h> /* The trivial gpiolib dispatchers */ diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 5c64d1a412c7..e8faedca6b14 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -183,14 +183,14 @@ EXPORT_SYMBOL_GPL(gpiod_to_chip); static int gpiochip_find_base(int ngpio) { struct gpio_device *gdev; - int base = ARCH_NR_GPIOS - ngpio; + int base = GPIO_DYNAMIC_BASE; - list_for_each_entry_reverse(gdev, &gpio_devices, list) { + list_for_each_entry(gdev, &gpio_devices, list) { /* found a free space? */ - if (gdev->base + gdev->ngpio <= base) + if (gdev->base >= base + ngpio) break; - /* nope, check the space right before the chip */ - base = gdev->base - ngpio; + /* nope, check the space right after the chip */ + base = gdev->base + gdev->ngpio; } if (gpio_is_valid(base)) { diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index aea9aee1f3e9..a7752cf152ce 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -11,40 +11,18 @@ #include <linux/gpio/driver.h> #include <linux/gpio/consumer.h> -/* Platforms may implement their GPIO interface with library code, +/* + * Platforms may implement their GPIO interface with library code, * at a small performance cost for non-inlined operations and some * extra memory (for code and for per-GPIO table entries). - * - * 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 -#if defined(CONFIG_ARCH_NR_GPIO) && CONFIG_ARCH_NR_GPIO > 0 -#define ARCH_NR_GPIOS CONFIG_ARCH_NR_GPIO -#else -#define ARCH_NR_GPIOS 512 -#endif -#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. + * At the end we want all GPIOs to be dynamically allocated from 0. + * However, some legacy drivers still perform fixed allocation. + * Until they are all fixed, leave 0-512 space for them. */ - -static inline bool gpio_is_valid(int number) -{ - return number >= 0 && number < ARCH_NR_GPIOS; -} +#define GPIO_DYNAMIC_BASE 512 struct device; struct gpio; @@ -140,12 +118,6 @@ static inline void gpio_unexport(unsigned gpio) #include <linux/kernel.h> -static inline bool gpio_is_valid(int number) -{ - /* only non-negative numbers are valid */ - return number >= 0; -} - /* platforms that don't directly support access to GPIOs through I2C, SPI, * or other blocking infrastructure can use these wrappers. */ @@ -169,4 +141,19 @@ static inline void gpio_set_value_cansleep(unsigned gpio, int value) #endif /* !CONFIG_GPIOLIB */ +/* + * "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 bool gpio_is_valid(int number) +{ + /* only non-negative numbers are valid */ + return number >= 0; +} + #endif /* _ASM_GENERIC_GPIO_H */ |