Hardware buttons in android custom device

Thanks Mr.Arun Joseph.

I have add the this code in board-am335xevm.c ( using BEAGLEBONE REV A5)

static struct gpio_keys_button BB_gpio_buttons[] = {
        {
                .code                  = KEY_HOME,
                .gpio                   = GPIO_TO_PIN(1,16),
                .active_low        = true,
                .desc                  = "Home",
                .type                    = EV_KEY,
                .wakeup             = 1,
        },

       {         .code                  = KEY_BACK,
                .gpio                   = GPIO_TO_PIN(1,17),
                .active_low         = true,
                .desc                   = "Back",
                .type                     = EV_KEY,
                .wakeup              = 1,
        },
};

static struct gpio_keys_platform_data BB_gpio_key_info = {
        .buttons        =BB_gpio_buttons'

        .nbuttons       = ARRAY_SIZE(BB_gpio_buttons),

};

I'm using beaglebone. GPIO1_16, GPIO1_17 is available in header, so i am plan to use this. Its complied successfully and i have converted as image. then i have create the KEY layout file as 

key 49 BACK WAKE_DROPPED

key 48 HOME WAKE

Then i  have booted the beaglebone and execute the " getevent " but my gpio-keys in not there.

root@android:/ # getevent
add device 1: /dev/input/event1
name: "lm75-temp"
add device 2: /dev/input/event0
name: "lm75-temp"
could not get driver version for /dev/input/mice, Not a typewriter

I dono where i did the mistake, and can anyone explain how to configure the PINMUX for this GPIO and how to initiate the GPIO configuration..

Thnks Mr.Umakanta 

I tried the steps what you have mentioned here, but till i cant get the GPIO driver node. I have write the details below.

1--> configured the GPIO driver  cd AOSP/kernel$ make menuconfig  in this i've select device drivers-->Inputdrivers-->keypad-->Gpio Buttons and GPIO driven matrix    keypad its selected as default 

2--> my coding is 

static struct gpio_keys_button BB_gpio_buttons[] = {
{
.code = KEY_HOME,
.gpio = GPIO_TO_PIN(1, 16),
.active_low = true,
.desc = "volume-up",
.type = EV_KEY,
.wakeup = 1,
},
{
.code = KEY_BACK,
.gpio = GPIO_TO_PIN(1, 17),
.active_low = true,
.desc = "volume-down",
.type = EV_KEY,
.wakeup = 1,
},
};

static struct gpio_keys_platform_data BB_gpio_key_info = {
.buttons = BB_gpio_buttons,
.nbuttons = ARRAY_SIZE(BB_gpio_buttons),
};

static struct platform_device BB_user_keys = {
.name = "gpio-keys",
.id = -1,
.dev = {
.platform_data = &BB_gpio_key_info,
},
};

Its my coding written in board-am335xevm.c. i didn't implement PINMUX here. then i build the ANDROID source

3--> Then i have registered the keypad device in init.rc as platform_device_register(&BB_user_keys);

            After complete these steps i have boot my device( Beaglebone REV A5) then execute the getevent its displays.

root@android:/ #getevent 

add device 1 : /dev/input/event1

    name: "lm75-temp"

add device 2 : /dev/input/event0

    name: "lm75-temp"

could not get drivers version for /dev/input/misc, Not a typewriter

     Here i didnt get my "gpio-keys" 

Here i've enclosed my Gpio button implementaion just only one button conected with GPIO1_16 (p9-15)  

Its my switch setup in Beaglebone.

Can you guess where i did mistake, or i've to change anyother files or lines..?

where i have to register my keypad device in inti.rc is there any specific section ?

Guide me to fix this..

Thanks in advance..!!

Thanks lot Mr.Umakanta Patro, you made my day.

Your reply make me understand about boardconfig and gpio config. As per my knowledge the gpio keys were already written in board-am335xevm.c its written and called under lcd_cape function. Regarding the flow board-am335xevm.c check the EEPROM in lcd_cape when its pluged and call the lcd_cape_keys_init function so its activated as default when the lcd_cape plug with the beaglebone.

By this knowledge i done the following things.

 copied the lcd_cape_keys_init(DEV_ON_DGHTR_BRD, PROFILE_NONE); from the board-am335xevm.c and i have paste under the dvi_init( DEV_ON_DGHTR_BRD, PROFILE_NONE); function. Hence when the Beaglebone activate the DVI_cape the LCD_cape_keys also configured as default.

else{
/* Setup DVI display if daughter card detected is not LCD cape. */
         dvi_init( DEV_ON_DGHTR_BRD, PROFILE_NONE);
         lcd_cape_keys_init(DEV_ON_DGHTR_BRD, PROFILE_NONE);
         return;
}

Then i booted my device and execute the " getevent" and its shows as

add device 1: /dev/input/event1

   name:  "lm75-temp"

add device 2: /dev/input/event0

   name:  "lm75-temp"

could not get driver version for /dev/input/mice, Not a typewriter

add device 3: /dev/input/event2

   name:  "gpio-keys"

So my gpio driver node is enabled.

But when i press the button i cant get the event like this

    /dev/input/event0: 0004 0004 00000002
    /dev/input/event0: 0001 009e 00000001
    /dev/input/event0: 0000 0000 00000000
    /dev/input/event0: 0004 0004 00000002

At where i did the mistake,Its confusing me lot.   

My circuit for gpio is mentioned in previous reply. 

i have checked by root@android:/# cat /dev/input/event2 in this also no response 

Can you guess my mistake.?

I hope i'm very near to complete this. so can you help me.?

Thanks in advance

Regards

Sangilikumar M

Thanks Mr.Umakanta Patro

     I have completed this task. I'm very happy to say this. you made my day. Its working fine. some prob in hardware i fixed it by testing with multi meter.

Really i'm thankful to you. 

Regards

Sangilikumar M

You are Wel Come... :-)

Hello Mr.Umakanta Patro

Have you handled USER LED in android via GPIO, or do you have idea about it.?

I have explained my problem here, kindly see that and give me a idea if you aware of it.

http://e2e.ti.com/support/embedded/android/f/509/p/212782/751724.aspx#751724

Regards

Sangilikumar M 

Hi ,

Is there any way to handle the same from linux, where getevent is not found.

I am trying to do the same and poll the value using cat but i have not observed any changes.

Regards

chandu

Hi chandu

         Are your sure dev node got created for our keypad ?

        If its created try to trace from dev node. i meant  cat /dev/<path to input node> you can observe something against your keypad status. 

Regards

Sangilikumar M

Hi Sangilikumar,

Yes dev node got created for you keypad under /dev/input/by-path/ .

I am trying to cat the event to capture the response (directly connecting a 3.3 v wire to pin and releasing instead of button), but i could not get the response.

Now i have connected a button and tested the same we are getting proper output.

So we have taken a evtest source to test this gpio keys, and it is working as expected.

Thanks

Chandu