diff options
Diffstat (limited to 'include/linux/scx200_gpio.h')
-rw-r--r-- | include/linux/scx200_gpio.h | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/include/linux/scx200_gpio.h b/include/linux/scx200_gpio.h new file mode 100644 index 000000000000..30cdd648ba79 --- /dev/null +++ b/include/linux/scx200_gpio.h @@ -0,0 +1,96 @@ +#include <linux/spinlock.h> + +u32 scx200_gpio_configure(int index, u32 set, u32 clear); + +extern unsigned scx200_gpio_base; +extern long scx200_gpio_shadow[2]; + +#define scx200_gpio_present() (scx200_gpio_base!=0) + +/* Definitions to make sure I do the same thing in all functions */ +#define __SCx200_GPIO_BANK unsigned bank = index>>5 +#define __SCx200_GPIO_IOADDR unsigned short ioaddr = scx200_gpio_base+0x10*bank +#define __SCx200_GPIO_SHADOW long *shadow = scx200_gpio_shadow+bank +#define __SCx200_GPIO_INDEX index &= 31 + +#define __SCx200_GPIO_OUT __asm__ __volatile__("outsl":"=mS" (shadow):"d" (ioaddr), "0" (shadow)) + +/* returns the value of the GPIO pin */ + +static inline int scx200_gpio_get(int index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR + 0x04; + __SCx200_GPIO_INDEX; + + return (inl(ioaddr) & (1<<index)) ? 1 : 0; +} + +/* return the value driven on the GPIO signal (the value that will be + driven if the GPIO is configured as an output, it might not be the + state of the GPIO right now if the GPIO is configured as an input) */ + +static inline int scx200_gpio_current(int index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_INDEX; + + return (scx200_gpio_shadow[bank] & (1<<index)) ? 1 : 0; +} + +/* drive the GPIO signal high */ + +static inline void scx200_gpio_set_high(int index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + set_bit(index, shadow); + __SCx200_GPIO_OUT; +} + +/* drive the GPIO signal low */ + +static inline void scx200_gpio_set_low(int index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + clear_bit(index, shadow); + __SCx200_GPIO_OUT; +} + +/* drive the GPIO signal to state */ + +static inline void scx200_gpio_set(int index, int state) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + if (state) + set_bit(index, shadow); + else + clear_bit(index, shadow); + __SCx200_GPIO_OUT; +} + +/* toggle the GPIO signal */ +static inline void scx200_gpio_change(int index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + change_bit(index, shadow); + __SCx200_GPIO_OUT; +} + +#undef __SCx200_GPIO_BANK +#undef __SCx200_GPIO_IOADDR +#undef __SCx200_GPIO_SHADOW +#undef __SCx200_GPIO_INDEX +#undef __SCx200_GPIO_OUT + +/* + Local variables: + compile-command: "make -C ../.. bzImage modules" + c-basic-offset: 8 + End: +*/ |