source: rtems/c/src/lib/libbsp/sparc/shared/gpio/gpiolib.c @ b583cc5f

/*  GPIOLIB interface implementation
 *
 *  COPYRIGHT (c) 2009.
 *  Cobham Gaisler AB.
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.com/license/LICENSE.
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include <gpiolib.h>

struct gpiolib_port;

struct gpiolib_port {
        struct gpiolib_port     *next;
        int                     minor;
        struct gpiolib_drv      *drv;
        void                    *handle;

        int                     open;
};

/* Root of GPIO Ports */
struct gpiolib_port *gpiolib_ports;

/* Number of GPIO ports registered */
static int port_nr;

/* 1 if libraray initialized */
static int gpiolib_initied = 0;

/* Insert a port first in ports list */
void gpiolib_list_add(struct gpiolib_port *port)
{
        port->next = gpiolib_ports;
        gpiolib_ports = port;
}

struct gpiolib_port *gpiolib_find(int minor)
{
        struct gpiolib_port *p;

        p = gpiolib_ports;
        while ( p && (p->minor != minor) ) {
                p = p->next;
        }
        return p;
}

struct gpiolib_port *gpiolib_find_by_name(char *name)
{
        struct gpiolib_port *p;
        struct gpiolib_info info;
        int (*get_info)(void *, struct gpiolib_info *);

        p = gpiolib_ports;
        while ( p ) {
                get_info = p->drv->ops->get_info;
                if ( get_info && (get_info(p->handle, &info) == 0) ) {
                        if ( strncmp(name, (char *)&info.devName[0], 64) == 0 ) {
                                break;
                        }
                }
                p = p->next;
        }
        return p;
}

void gpiolib_list_remove(struct gpiolib_port *port)
{
        
}

int gpiolib_drv_register(struct gpiolib_drv *drv, void *handle)
{
        struct gpiolib_port *port;

        if ( !drv || !drv->ops )
                return -1;

        port = malloc(sizeof(*port));
        if ( port == NULL )
                return -1;

        memset(port, 0, sizeof(*port));
        port->handle = handle;
        port->minor = port_nr++;
        port->drv = drv;

        gpiolib_list_add(port);

        return 0;
}

void gpiolib_show(int port, void *handle)
{
        struct gpiolib_port *p;

        if ( port == -1 ) {
                p = gpiolib_ports;
                while (p != NULL) {
                        if ( p->drv->ops->show )
                                p->drv->ops->show(p->handle);
                        p = p->next;
                }
        } else {
                if ( handle ) {
                        p = handle;
                } else {
                        p = gpiolib_find(port);
                }
                if ( p == NULL ) {
                        printf("PORT %d NOT FOUND\n", port);
                        return;
                }
                if ( p->drv->ops->show )
                        p->drv->ops->show(p->handle);
        }
}

void *gpiolib_open_internal(int port, char *devName)
{
        struct gpiolib_port *p;

        if ( gpiolib_initied == 0 )
                return NULL;

        /* Find */
        if ( port >= 0 ) {
                p = gpiolib_find(port);
        } else {
                p = gpiolib_find_by_name(devName);
        }
        if ( p == NULL )
                return NULL;

        if ( p->open )
                return NULL;

        p->open = 1;
        return p;
}

void *gpiolib_open(int port)
{
        return gpiolib_open_internal(port, NULL);
}

void *gpiolib_open_by_name(char *devName)
{
        return gpiolib_open_internal(-1, devName);
}

void gpiolib_close(void *handle)
{
        struct gpiolib_port *p = handle;

        if ( p && p->open ) {
                p->open = 0;
        }
}

int gpiolib_set_config(void *handle, struct gpiolib_config *cfg)
{
        struct gpiolib_port *port = handle;

        if ( !port || !cfg )
                return -1;

        if ( !port->drv->ops->config )
                return -1;

        return port->drv->ops->config(port->handle, cfg);
}

int gpiolib_set(void *handle, int dir, int outval)
{
        struct gpiolib_port *port = handle;

        if ( !port )
                return -1;

        if ( !port->drv->ops->set )
                return -1;

        return port->drv->ops->set(port->handle, dir, outval);  
}

int gpiolib_get(void *handle, int *inval)
{
        struct gpiolib_port *port = handle;

        if ( !port || !inval)
                return -1;

        if ( !port->drv->ops->get )
                return -1;

        return port->drv->ops->get(port->handle, inval);
}

/*** IRQ Functions ***/
int gpiolib_irq_register(void *handle, void *func, void *arg)
{
        struct gpiolib_port *port = handle;

        if ( !port )
                return -1;

        if ( !port->drv->ops->irq_register )
                return -1;

        return port->drv->ops->irq_register(port->handle, func, arg);
}

int gpiolib_irq_opts(void *handle, unsigned int options)
{
        struct gpiolib_port *port = handle;

        if ( !port )
                return -1;

        if ( !port->drv->ops->irq_opts )
                return -1;

        return port->drv->ops->irq_opts(port->handle, options);
}

int gpiolib_irq_clear(void *handle)
{
        return gpiolib_irq_opts(handle, GPIOLIB_IRQ_CLEAR);
}

int gpiolib_irq_force(void *handle)
{
        return gpiolib_irq_opts(handle, GPIOLIB_IRQ_FORCE);
}

int gpiolib_irq_enable(void *handle)
{
        return gpiolib_irq_opts(handle, GPIOLIB_IRQ_ENABLE);
}

int gpiolib_irq_disable(void *handle)
{
        return gpiolib_irq_opts(handle, GPIOLIB_IRQ_DISABLE);
}

int gpiolib_irq_mask(void *handle)
{
        return gpiolib_irq_opts(handle, GPIOLIB_IRQ_MASK);
}

int gpiolib_irq_unmask(void *handle)
{
        return gpiolib_irq_opts(handle, GPIOLIB_IRQ_UNMASK);
}


/*** Initialization ***/
int gpiolib_initialize(void)
{
        if ( gpiolib_initied != 0 )
                return 0;

        /* Initialize Libarary */
        port_nr = 0;
        gpiolib_ports = 0;
        gpiolib_initied = 1;
        return 0;
}