gpioinit.c

Go to the documentation of this file.

/* gpioinit.c - gpioinit */

#include <xinu.h>

struct  gpiocblk    gpiotab[NGPIO];

/*------------------------------------------------------------------------
 *  gpioinit  -  Initialize settings for a gpio device
 *------------------------------------------------------------------------
 */
devcall gpioinit(
      struct dentry *devptr     /* Entry in device switch table */
    )
{
    struct gpio_csreg *csrptr;  /* Pointer ot GPIO CSRs     */
    struct gpiocblk *gpioptr;   /* Pointer ot GPIO Control block*/
    uint32 *fclkreg;        /* FCLK Register for debounce   */

    csrptr = (struct gpio_csreg *)(devptr->dvcsr);
    gpioptr = &gpiotab[devptr->dvminor];

    /* Get the FCLK Register for the corresponding GPIO module */

    if(csrptr == GPIO1_BASE)    {
        fclkreg = PRCM_FCLK_GPIO1;
    } else if(csrptr == GPIO2_BASE) {
        fclkreg = PRCM_FCLK_GPIO2;
    } else if(csrptr == GPIO3_BASE) {
        fclkreg = PRCM_FCLK_GPIO3;
    } else {
        /* GPIO0 FCLK is ON by default */
        fclkreg = NULL;
    }

    /* Initialize register values */

    csrptr->sysconfig = 0x0;
    
    /* Disable output for all pins */

    csrptr->oe = 0xFFFFFFFF;

    /* Clear all pending interrupts */

    csrptr->irqstatus0 = 0xFFFFFFFF;
    csrptr->irqstatus1 = 0xFFFFFFFF;

    /* Disable all interrupts */

    csrptr->irqclear0 = 0xFFFFFFFF;
    csrptr->irqclear1 = 0xFFFFFFFF;
    
    /* Clear all pins */

    csrptr->clear_data = 0xFFFFFFFF;
    
    /* Clear wakeup settings */

    csrptr->irqwaken0 = 0x0;
    csrptr->irqwaken1 = 0x0;

    /* Clear all interrupt trigger settings */

    csrptr->rising  = 0x0;
    csrptr->falling = 0x0;
    csrptr->level0  = 0x0;
    csrptr->level1  = 0x0;

    /* Disable debouncing */

    csrptr->deb_ena = 0x0;

    /* Setup debouncing clock */

    if(fclkreg != NULL) {
        *fclkreg |= PRCM_FCLK_BIT;
    }

    /* Interrupt A */

    set_evec( devptr->dvirq, (uint32)devptr->dvintr );

    /* Interrupt B is the next interrupt line */

    set_evec( (devptr->dvirq)+1, (uint32)devptr->dvintr );

    gpioptr->gphookfn = NULL;

    return OK;
}