diff options
Diffstat (limited to 'arch/arm/mach-davinci/include')
| -rw-r--r-- | arch/arm/mach-davinci/include/mach/gpio.h | 73 |
1 files changed, 34 insertions, 39 deletions
diff --git a/arch/arm/mach-davinci/include/mach/gpio.h b/arch/arm/mach-davinci/include/mach/gpio.h index ec151ccf1e8..b3a2961f0f4 100644 --- a/arch/arm/mach-davinci/include/mach/gpio.h +++ b/arch/arm/mach-davinci/include/mach/gpio.h @@ -14,6 +14,7 @@ #define __DAVINCI_GPIO_H #include <linux/io.h> +#include <asm-generic/gpio.h> #include <mach/hardware.h> /* @@ -27,13 +28,16 @@ * need to pay attention to PINMUX0 and PINMUX1 to be sure those pins are * used as gpios, not with other peripherals. * - * GPIOs are numbered 0..(DAVINCI_N_GPIO-1). For documentation, and maybe - * for later updates, code should write GPIO(N) or: + * On-chip GPIOs are numbered 0..(DAVINCI_N_GPIO-1). For documentation, + * and maybe for later updates, code should write GPIO(N) or: * - GPIOV18(N) for 1.8V pins, N in 0..53; same as GPIO(0)..GPIO(53) * - GPIOV33(N) for 3.3V pins, N in 0..17; same as GPIO(54)..GPIO(70) * * For GPIO IRQs use gpio_to_irq(GPIO(N)) or gpio_to_irq(GPIOV33(N)) etc * for now, that's != GPIO(N) + * + * GPIOs can also be on external chips, numbered after the ones built-in + * to the DaVinci chip. For now, they won't be usable as IRQ sources. */ #define GPIO(X) (X) /* 0 <= X <= 70 */ #define GPIOV18(X) (X) /* 1.8V i/o; 0 <= X <= 53 */ @@ -67,11 +71,11 @@ __gpio_to_controller(unsigned gpio) void *__iomem ptr; if (gpio < 32) - ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x10); + ptr = IO_ADDRESS(DAVINCI_GPIO_BASE + 0x10); else if (gpio < 64) - ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x38); + ptr = IO_ADDRESS(DAVINCI_GPIO_BASE + 0x38); else if (gpio < DAVINCI_N_GPIO) - ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x60); + ptr = IO_ADDRESS(DAVINCI_GPIO_BASE + 0x60); else ptr = NULL; return ptr; @@ -83,25 +87,17 @@ static inline u32 __gpio_mask(unsigned gpio) } /* The get/set/clear functions will inline when called with constant - * parameters, for low-overhead bitbanging. Illegal constant parameters - * cause link-time errors. + * parameters referencing built-in GPIOs, for low-overhead bitbanging. * - * Otherwise, calls with variable parameters use outlined functions. + * Otherwise, calls with variable parameters or referencing external + * GPIOs (e.g. on GPIO expander chips) use outlined functions. */ -extern int __error_inval_gpio(void); - -extern void __gpio_set(unsigned gpio, int value); -extern int __gpio_get(unsigned gpio); - static inline void gpio_set_value(unsigned gpio, int value) { - if (__builtin_constant_p(value)) { + if (__builtin_constant_p(value) && gpio < DAVINCI_N_GPIO) { struct gpio_controller *__iomem g; u32 mask; - if (gpio >= DAVINCI_N_GPIO) - __error_inval_gpio(); - g = __gpio_to_controller(gpio); mask = __gpio_mask(gpio); if (value) @@ -111,48 +107,47 @@ static inline void gpio_set_value(unsigned gpio, int value) return; } - __gpio_set(gpio, value); + __gpio_set_value(gpio, value); } /* Returns zero or nonzero; works for gpios configured as inputs OR - * as outputs. + * as outputs, at least for built-in GPIOs. * - * NOTE: changes in reported values are synchronized to the GPIO clock. - * This is most easily seen after calling gpio_set_value() and then immediatly - * gpio_get_value(), where the gpio_get_value() would return the old value - * until the GPIO clock ticks and the new value gets latched. + * NOTE: for built-in GPIOs, changes in reported values are synchronized + * to the GPIO clock. This is easily seen after calling gpio_set_value() + * and then immediately gpio_get_value(), where the gpio_get_value() will + * return the old value until the GPIO clock ticks and the new value gets + * latched. */ - static inline int gpio_get_value(unsigned gpio) { - struct gpio_controller *__iomem g; - - if (!__builtin_constant_p(gpio)) - return __gpio_get(gpio); + struct gpio_controller *__iomem g; - if (gpio >= DAVINCI_N_GPIO) - return __error_inval_gpio(); + if (!__builtin_constant_p(gpio) || gpio >= DAVINCI_N_GPIO) + return __gpio_get_value(gpio); g = __gpio_to_controller(gpio); - return !!(__gpio_mask(gpio) & __raw_readl(&g->in_data)); + return __gpio_mask(gpio) & __raw_readl(&g->in_data); } -/* powerup default direction is IN */ -extern int gpio_direction_input(unsigned gpio); -extern int gpio_direction_output(unsigned gpio, int value); - -#include <asm-generic/gpio.h> /* cansleep wrappers */ - -extern int gpio_request(unsigned gpio, const char *tag); -extern void gpio_free(unsigned gpio); +static inline int gpio_cansleep(unsigned gpio) +{ + if (__builtin_constant_p(gpio) && gpio < DAVINCI_N_GPIO) + return 0; + else + return __gpio_cansleep(gpio); +} static inline int gpio_to_irq(unsigned gpio) { + if (gpio >= DAVINCI_N_GPIO) + return -EINVAL; return DAVINCI_N_AINTC_IRQ + gpio; } static inline int irq_to_gpio(unsigned irq) { + /* caller guarantees gpio_to_irq() succeeded */ return irq - DAVINCI_N_AINTC_IRQ; } |