gpioread.c File Reference

#include <xinu.h>

Include dependency graph for gpioread.c:

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Functions
devcall	gpioread (struct dentry *devptr, char *value, int32 pinmask)

Function Documentation

gpioread()

devcall gpioread	(	struct dentry *	devptr,
		char *	value,
		int32	pinmask
	)

Definition at line 9 of file gpioread.c.

References gpio_csreg::datain, dentry::dvcsr, and OK.

{
    struct gpio_csreg *csrptr;  /* Pointer to GPIO CSRs     */

    /* Obtain the address of the CSR from the device switch table   */

    csrptr = (struct gpio_csreg *)(devptr->dvcsr);
    
    /* Access the GPIO pins, use the mask to select a subset, and   */
    /*  store the result in the specified buffer        */

    *((uint32 *)value) = csrptr->datain & pinmask;

    return OK;
}