using of a I/O

I want to use an input of the dm365 not used by the board, just by adding a switch.

How I can use it in the soft?

I'm working on LeopardBoard 365, I saw in the Hardware Guide the Expansion port pin assignment. So I think that I can use the GPIO 22 to 25 and 62 to 64 (I just need a GPIO). How to configurate the GPIO as an input and how to have the intput value (0 or 1)?

Thanks in advance

I'm working on LeopardBoard 365, I saw in the Hardware Guide the Expansion port pin assignment. So I think that I can use the GPIO 22 to 25 and 62 to 64 (I just need a GPIO). How to configurate the GPIO as an input and how to have the intput value (0 or 1)?

Thanks in advance

I don't succeed in include gpio library in my soft, it doesn't find it

I want to use the file asm/arch/gpio.h, but I can't include it in my own application just by written #include <asm/arch/gpio.h>

How use the GPIO function??

asm/arch/gpio.h is only usable by code running in kernel.

You can use the /sys file system to access GPIO (enable via make config -> kernel -> device drivers -> gpio -> /sys/class/gpio).  Then you can just read and write files in the /sys/class/gpio directory to control GPIOs from a Linux application.

CFLAGS  += -I$(DEVDIR)/kernel/$(KERNEL)/include

Todd

To answer your question, if you want to be able to include Linux kernel header files (useful when Linux applications make ioctl() calls), then in the Makefile add,

I can't find gpio->/sys/class/gpio in the devices drivers menu

And il the /sys/class/gpio there are 2 files that I can't open. It's in this directory that I have to create file?

In this link designsomething.org/.../134.aspx  it is written that we can read and write registers. How know the registers address like a GPIO output register?

I found registers addresses in dm365-registers.c. I want to see the output of the GPIO23, is it really at the address 0x01C67020 (GPIO_BANK01_IN)?

Busybox contains the devmem utility, that allows you to read and write hardware registers.

cd $DEVDIR

make config # -> file system, applications, busybox -> misc -> devmem

Here is an example when I was looking into an RGB888 output for the LI-DVI1 board

>From sprufg9b/pg 48:  Table 12. Interface Signals For Parallel RGB Digital Displays

PINMUX4[13:12].GIO33 = 3

PINMUX4[11:10].GIO32 = 3

PINMUX4[7:6].GIO30 = 3

PINMUX4[5:4].GIO29 = 3

PINMUX4[3:2].GIO28 = 3

PINMUX4[1:0].GIO27 = 3

ARM user's guide sprufg5a/pg 127 Pin Mux 4 (PINMUX4) Register 0x01C40010

/ # devmem 0x01C40010 w

0x51735455

0101 0100 0101 0101 <- was

0111 1100 1111 1111 <-for RGB888

This appears to be wrong (SPI1/SPI2 is enabled instead of RBG888).  I think the value needed for RBG888 should be

0x51733CFF

/ # devmem 0x01C40010 w 0x51733CFF

and verifying I properly wrote the register

/ # devmem 0x01C40010 w

0x51733CFF

Thanks.

I have connected a push button in the expansion port (GPIO22, GND and 3.3V), but I don't understand, whereas I don't configure GPIO22,  it seems to be a reset!!

I wanted just use this input in my soft, but I can't: when I put in on, it resets!

Is someone has an idea? Problem of hardware Leopard?

sorry: a error of button connection!

I've added in board-dm365-evm.c the following lines in order to initialize the GPIO22:

davinci_cfg_reg(DM365_GPIO22,PINMUX_RESV);
gpio_request(GPIO22,"gpio_button");
gpio_direction_input(22);

and in  mux.c I've added:

/*GPIO22, button*/

DM365_GPIO22,

in the mux_cfg file I don't know what add, I've tried with:

MUX_CFG("DM365_GPIO22",         3,   22,    3,    0,    0)

but when I boot, it stops at "Starting Kernel...."

Please help me to configure this GPIO as an input.

Thanks

rectification of the post :

davinci_cfg_reg(DM365_GPIO22,PINMUX_RESV);

gpio_request(22,"gpio_button");

gpio_direction_input(22);

please: it's very important