Gpio read module

wiegand-gpio.c

/* wiegand-gpio.c.
 *.
 * Wiegand test driver using GPIO an interrupts..
 *
 */

/* Standard headers for LKMs */
#include <linux/module.h><----->/* Needed by all modules */
#include <linux/kernel.h><----->/* Needed for KERN_INFO */
#include <linux/kobject.h>
#include <linux/string.h>
#include <linux/sysfs.h>
#include <linux/timer.h>

#include <linux/tty.h>      /* console_print() interface */
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/interrupt.h>

#include <asm/irq.h>
#include <mach/gpio.h>

const int Readers[][4] ={
{0,1,2,3},
{1,4,5,6}
};
int irq_gpio01,irq_gpio02;
static struct wiegand
{
  int startParity;
  int readNum;
  char buffer[MAX_WIEGAND_BYTES];
  int currentBit;
  unsigned int lastFacilityCode;
  unsigned int lastCardNumber;
}
wiegand;

static struct timer_list timer;


irqreturn_t wiegand_data_isr(int irq, void *dev_id);


void wiegand_clear(struct wiegand *w)
{
  w->currentBit = 0;
}

void wiegand_init(struct wiegand *w)
{
  wiegand_clear(w);
}

void wiegand_timer(unsigned long data)
{
  struct wiegand *w = (struct wiegand *) data;
  printk("wiegand read %d bit complete\n",w->currentBit);
  w->currentBit=0;
}

int init_module()
{
  int retval;
  int err;.
  printk("Pcduino wiegand intialising\n");

  wiegand_init(&wiegand);

  err = gpio_request(Readers[0][3],"Beep 0 ON");
  if (err)
  {
    printk(KERN_DEBUG"Could not request pin %d for GPIO.\n", Readers[0][3]);
    return -EIO;
  }
  err = gpio_request(Readers[1][3],"Beep 1  ON");
  if (err)
  {
    printk(KERN_DEBUG"Could not request pin %d for GPIO.\n", Readers[1][3]);
    return -EIO;
  }
  err = gpio_request(Readers[0][1],"data0");
 if (err)
  {
    printk(KERN_DEBUG"Could not request pin %d for GPIO.\n", Readers[0][1]);
    return -EIO;
  }
  
  
  err = gpio_request(Readers[0][2],"data1");
  if (err)
  {
    printk(KERN_DEBUG"Could not request pin %d for GPIO.\n", Readers[0][2]);
    return -EIO;
  }


  if(gpio_direction_output(Readers[0][3],1))
  {
    printk(KERN_DEBUG"Could not set pin %i for GPIO output.\n", Readers[0][3]);
    return -EIO;
  }
 if(gpio_direction_output(Readers[1][3],1))
  {
    printk(KERN_DEBUG"Could not set pin %i for GPIO output.\n", Readers[1][3]);
    return -EIO;
  }


  /** Set pin as GPIO input, with internal pull up */
  if(gpio_direction_input(Readers[0][1]))
  {
    printk(KERN_DEBUG"Could not set pin %i for GPIO input.\n", Readers[0][1]);
    return -EIO;
  }

  /** Set pin as GPIO input, with internal pull up */
  if(gpio_direction_input(Readers[0][2]))
  {
    printk(KERN_DEBUG"Could not set pin %i for GPIO input.\n", Readers[0][2]);
    return -EIO;
}

    irq_gpio01 = gpio_to_irq(Readers[0][1]);
    if (irq_gpio01<0) {
     printk(KERN_DEBUG"Unable to get irq number, %d\n",irq_gpio01);

    }
     printk(KERN_DEBUG"register IRQ %d\n",irq_gpio01);
  /** Request IRQ for pin */
  if(request_irq(irq_gpio01, wiegand_data_isr,IRQF_TRIGGER_FALLING, "wiegand_data", &wiegand))

  {
    printk(KERN_DEBUG"Can't register IRQ %d\n", irq_gpio01);
    return -EIO;
  }


  irq_gpio02 = gpio_to_irq(Readers[0][2]);
    if (irq_gpio02<0) {
     printk(KERN_DEBUG"Unable to get irq number, %d\n",irq_gpio02);


    }
     printk(KERN_DEBUG"register IRQ %d\n",irq_gpio02);

 if(request_irq(irq_gpio02, wiegand_data_isr,IRQF_TRIGGER_FALLING, "wiegand_data", &wiegand))
  {
    printk(KERN_DEBUG"Can't register IRQ %d\n", irq_gpio02);
    return -EIO;
  }

  //setup the timer
  init_timer(&timer);
  timer.function = wiegand_timer;
  timer.data = (unsigned long) &wiegand;

  //turn off leds.
  gpio_set_value(Readers[0][3], 1);
 gpio_set_value(Readers[1][3], 1);

  printk("wiegand ready\n");
  return retval;
}

irqreturn_t wiegand_data_isr(int irq, void *dev_id)
 {
  struct wiegand *w = (struct wiegand *)dev_id;
// int data0 = gpio_get_value(Readers[0][1]);
// int data1 = gpio_get_value(Readers[0][2]);
  w->currentBit++;
  printk("[%li] %d  IRQ = %d\n",jiffies,w->currentBit,irq);
  return IRQ_HANDLED;
}

void cleanup_module()
{
  free_irq(irq_gpio01, &wiegand);
  free_irq(irq_gpio02, &wiegand);
  gpio_set_value(Readers[0][3], 1);
  gpio_set_value(Readers[1][3], 1);

  printk("wiegand removed\n");
}


MODULE_DESCRIPTION("Wiegand test GPIO driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("test");