#ifndef RPI_H_
#define RPI_H_

/* gpio modes. */
#define PI_INPUT  0
#define PI_OUTPUT 1
#define PI_ALT0   4
#define PI_ALT1   5
#define PI_ALT2   6
#define PI_ALT3   7
#define PI_ALT4   3
#define PI_ALT5   2

void gpioSetMode(unsigned gpio, unsigned mode);
int gpioGetMode(unsigned gpio);

/* Values for pull-ups/downs off, pull-down and pull-up. */
#define PI_PUD_OFF  0
#define PI_PUD_DOWN 1
#define PI_PUD_UP   2
void gpioSetPullUpDown(unsigned gpio, unsigned pud);

int gpioRead(unsigned gpio);
void gpioWrite(unsigned gpio, unsigned level);
void gpioTrigger(unsigned gpio, unsigned pulseLen, unsigned level);

/* Bit (1<<x) will be set if gpio x is high. */
uint32_t gpioReadBank1(void);
uint32_t gpioReadBank2(void);

/* To clear gpio x bit or in (1<<x). */
void gpioClearBank1(uint32_t bits);
void gpioClearBank2(uint32_t bits);

/* To set gpio x bit or in (1<<x). */
void gpioSetBank1(uint32_t bits);
void gpioSetBank2(uint32_t bits);

unsigned gpioHardwareRevision(void);

/* Returns the number of microseconds after system boot. Wraps around
   after 1 hour 11 minutes 35 seconds.
*/
uint32_t gpioTick(void);

int gpioInitialise(void);

#endif /* RPI_H_ */