KEYBOARD BASED GPIO PROGRAM

Hi,

I AM WORKING ON OMAP5912 OSK.

I am writing a keyboard based gpio program to write a value '1' to the free gpio pin when a key was pressed.

For that I modified the gpio-switch.c program. I am using the up arrow

key which is mapped to gpio7.

By pressing this key I am unable to write

a value '1' to the gpio pin 7.

At the shell prompt I am able to see a logic '0' value at gpio pin 7 with the following message

Value of pin # 7 = 0

up (GPIO 7) is now disconnected

I am supposed to get the Value of pin # 7 = 1

Here is my gpio-switch code

#define OMAP_GPIO_SW_POLL_DELAY 10

#define LED_GPIO 7

const struct omap_gpio_switch_config omap_left_switch = {

.name = "left",

.type = OMAP_GPIO_SWITCH_TYPE_CONNECTION,

.gpio = 6,

.flags = OMAP_GPIO_SWITCH_FLAG_INVERTED,

.key_code = KEY_LEFT

};

const struct omap_gpio_switch_config omap_enter_switch = {

.name = "enter",

.type = OMAP_GPIO_SWITCH_TYPE_CONNECTION,

.gpio = 12,

.flags = OMAP_GPIO_SWITCH_FLAG_INVERTED,

.key_code = KEY_ENTER

};

const struct omap_gpio_switch_config omap_up_switch = {

.name = "up",

.type = OMAP_GPIO_SWITCH_TYPE_CONNECTION,

.gpio = 7,

.flags = OMAP_GPIO_SWITCH_FLAG_INVERTED,

.key_code = KEY_UP

};

const struct omap_gpio_switch_config omap_down_switch = {

.name = "down",

.type = OMAP_GPIO_SWITCH_TYPE_CONNECTION,

.gpio = 15,

.flags = OMAP_GPIO_SWITCH_FLAG_INVERTED,

.key_code = KEY_DOWN

};

const struct omap_gpio_switch_config *omap_switches[] = {

&omap_left_switch,

&omap_enter_switch,

&omap_up_switch,

&omap_down_switch,

NULL /* Guard */

};

static void gpio_sw_handler(void *data)

{

    struct gpio_switch *sw = data;

    int state = gpio_sw_get_state(sw);

 

    if (sw->state == state)

          return;

 

    if (sw->type == OMAP_GPIO_SWITCH_TYPE_CONNECTION)

          kobject_uevent(&sw->pdev.dev.kobj, KOBJ_CHANGE,

                    &dev_attr_connection_switch.attr);

    else

          kobject_uevent(&sw->pdev.dev.kobj, KOBJ_CHANGE,

                    &dev_attr_cover_switch.attr);

    sw->state = state;

    input_report_key(&omap_sw_kp_dev, sw->key_code, state);

    

    /*** [START]: code for writing some value to GPIO 17 ***/

 

    if(sw->key_code==KEY_UP)

    {

          if(led_glow(sw))

              printk(KERN_ERR "led_glow:failed ");

    }    

    

    /*** [END]: code for writing some value to GPIO 17 ***/          

static int led_glow(struct gpio_switch *ctrlsw)

{

    /* requesting for LED_GPIO */

    if(omap_request_gpio(LED_GPIO)<0)

          return -1;

    

    /* setting LED_GPIO as output pin */

    omap_set_gpio_direction(LED_GPIO,0);

 

    /* writing to LED_GPIO the state of KEY_UP */

    omap_set_gpio_dataout(LED_GPIO,ctrlsw->state);

 

    /* printing the value of led_gpio pin */

    printk("value of pin # %d = %d\n",LED_GPIO,omap_get_gpio_datain(LED_GPIO));

 

    return 0;

}

But if I alone run the following code with out using the switch dependency, I am able to set the GPIO pin to 1 and I can observe the change from logic 0 to Logic 1 in the C.R.O

/* define any of the valid GPIO pins as LED_GPIO */
#define LED_GPIO 7

/* Defines the value written to the pin defined as LED_GPIO */ #define LED_STATUS 1

  MODULE_LICENSE("Dual BSD/GPL");
   
   
   
  int init_module(void)
  {
        /* requesting for LED_GPIO */
        if(omap_request_gpio(LED_GPIO)<0)
        {
        printk("[ERROR]: Failed in allocating the requested GPIO Pin \n");
              return -1;
        }

        /* setting LED_GPIO as output pin */
        omap_set_gpio_direction(LED_GPIO,0);
   
        /* writing to LED_GPIO the value of LED_STATUS */
        omap_set_gpio_dataout(LED_GPIO,1);
   
        /* printing the value of LED_GPIO pin */

printk("value of pin # %d = %d\n",LED_GPIO,omap_get_gpio_datain(LED_GPIO));

        return 0;

}

  Void cleanup_module (void)
  {
        omap_free_gpio(LED_GPIO);     
        printk("[SUCCESS]: LED_GLOW Module unregistered successfull.\n");
  }

Please suggest where I had gone wrong.

With Regards

Azharuddin

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