kb_gpio.c

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/*-------------------------------------------------------------------------------
 * Project: KoreBot Library     
 * $Author: pbureau $
 * $Date: 2005/01/20 08:41:54 $
 * $Revision: 1.1 $
 * 
 * 
 * $Header: /home/cvs/libkorebot/src/kb_gpio.c,v 1.1 2005/01/20 08:41:54 pbureau Exp $
 */

#include <sys/mman.h>
#include "korebot.h"
#include "kb_pxa_register.h"

#define MAP_SIZE 4096UL
#define MAP_MASK (MAP_SIZE - 1)

#define MEMDEV "/dev/mem"
#define MAXIO 84

#define reg_val(reg) *((unsigned long *)reg)

static void* map_base;
static int fd;

static void bit_set(unsigned long addr,unsigned gpio)
{
  void * virt_addr;
  unsigned long mask;

  virt_addr = map_base + ((addr+(gpio/32)*4) & MAP_MASK);
  mask      = 1 << (gpio%32);
  
  reg_val(virt_addr) = reg_val(virt_addr) | mask;
}

static void bit_clear(unsigned long addr,unsigned gpio)
{
  void * virt_addr;
  unsigned long mask;

  virt_addr = map_base + ((addr+(gpio/32)*4) & MAP_MASK);
  mask      = 1 << (gpio%32);
  
  reg_val(virt_addr) = reg_val(virt_addr) & ~mask;
}

static int bit_test(unsigned long addr,unsigned gpio)
{
  void * virt_addr;
  unsigned long mask;

  virt_addr = map_base + ((addr+(gpio/32)*4) & MAP_MASK);
  mask      = 1 << (gpio%32);
  
  if(reg_val(virt_addr) & mask)
    return 1;
  else
    return 0;
}

int kb_gpio_init()
{

  /* Open the memory device */
  if((fd = open(MEMDEV, O_RDWR | O_SYNC)) == -1)
  {
    KB_ERROR("kb_gpio_init",KB_ERROR_FILEOPEN,MEMDEV);
    return -KB_ERROR_FILEOPEN;
  }

  /* map registers to user space */
  map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, GPIO_BASE & ~MAP_MASK);
  if(map_base == (void *) -1) 
  {
    KB_ERROR("kb_gpio_init",KB_ERROR_MMAP,GPIO_BASE & ~MAP_MASK);
    return -KB_ERROR_MMAP;
  }

  return 0;
}

int kb_gpio_cleanup()
{
    if(munmap(map_base, MAP_SIZE) == -1) KB_ERROR("kb_gpio_cleanup",KB_ERROR_MMAP,map_base);
    close(fd);
}

int kb_gpio_mode()
{
}

void kb_gpio_function(unsigned gpio, unsigned function)
{
  if(gpio > MAXIO || function > 3)
    KB_ERROR("kb_gpio_get",KB_ERROR_INVALID);

  if((function & 0x1))
    bit_set(GAFR,2*gpio);
  else
    bit_clear(GAFR,2*gpio);

  if((function & 0x2))
    bit_set(GAFR,(2*gpio)+1);
  else
    bit_clear(GAFR,(2*gpio)+1);
}

void kb_gpio_dir(unsigned gpio, unsigned dir)
{
  if(gpio > MAXIO)
    KB_ERROR("kb_gpio_get",KB_ERROR_INVALID);

  if(dir)
    bit_clear(GPDR,gpio);
  else
    bit_set(GPDR,gpio);
}

void kb_gpio_set(unsigned gpio)
{
  if(gpio > MAXIO)
    KB_ERROR("kb_gpio_get",KB_ERROR_INVALID);

  bit_set(GPSR,gpio);
}

void kb_gpio_clear(unsigned gpio)
{
  if(gpio > MAXIO)
    KB_ERROR("kb_gpio_get",KB_ERROR_INVALID);

  bit_set(GPCR,gpio);
}

int kb_gpio_get(unsigned gpio)
{
  if(gpio > MAXIO)
  {
    KB_ERROR("kb_gpio_get",KB_ERROR_INVALID);
    return -KB_ERROR_INVALID;
  }

  return bit_test(GPLR, gpio);
}

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