void hw_fini(void)
{
if(gpio_rs_fd >= 0)
sysfs_gpio_close(gpio_rs_fd, GPIO_RS_PIN);
if(spi_fd >= 0)
close(spi_fd);
gpio_rs_fd = spi_fd = -1;
}
struct mux_spi *
mux_spi_open(){
struct mux_spi *p;
char buf[64];
int i;
p = calloc(1,sizeof(struct mux_spi));
for(i=0;i<NUM_SPI;i++)
p->spi_fd[i]=-1;
for(i=0;i<NUM_GPIO;i++){
p->gpio[i] = sysfs_gpio_open(gpio_num[i]);
if(!p->gpio[i])
goto err;
/* initialize multiplexer bits to 0 */
if(sysfs_gpio_direction(p->gpio[i],1) ||
sysfs_gpio_value(p->gpio[i],0)
)
goto err;
}
for(i=0;i<NUM_SPI;i++){
sprintf(buf,"/dev/spidev0.%d",i);
p->spi_fd[i] = open(buf,O_RDWR);
if(p->spi_fd[i] == -1){
perror(buf);
goto err;
}
if(ioctl(p->spi_fd[i],SPI_IOC_RD_BITS_PER_WORD,&p->spibpw[i])){
perror("ioctl(SPI_IOC_RD_BITS_PER_WORD)");
goto err;
}
if(ioctl(p->spi_fd[i],SPI_IOC_RD_MODE,&p->spimode[i])){
perror("ioctl(SPI_IOC_RD_MODE)");
goto err;
}
if(ioctl(p->spi_fd[i],SPI_IOC_RD_LSB_FIRST,&p->spilsb[i])){
perror("ioctl(SPI_IOC_RD_LSB_FIRST)");
goto err;
}
fprintf(stderr,"Opened %s as fd %d (0x%02x, %d, %d).\n",
buf,p->spi_fd[i],
p->spimode[i],p->spibpw[i],p->spilsb[i]);
}
return p;
err:
for(i=0;i<NUM_SPI;i++){
if(p->spi_fd[i] != -1)
close(p->spi_fd[i]);
}
for(i=0;i<NUM_GPIO;i++){
if(p->gpio[i])
sysfs_gpio_close(p->gpio[i]);
}
return NULL;
}
