Unable to toggle GPIO using SYS filesystem

Srinivas,

Check to make sure the pins are muxed correctly I had the same issue yesterday using the 3.8 kernel, and it turned out the default pinmux settings did not bring out the GPIO pins.

-c

Hi Chris,

You are right.

As explained in below link

http://processors.wiki.ti.com/index.php/AM335x_PSP_User’s_Guide#Method_I_-_Modify_Linux_Kernel.2C_rebuilt_and_use

I modified the “arch/arm/mach-omap2/board-am335xevm.c” file as below and compiled the kernel.

213 static struct omap_board_mux board_mux[] __initdata = {
214
215 // New line added by me.
216 AM33XX_MUX(GPMC_AD6, OMAP_MUX_MODE7 | AM33XX_PIN_OUTPUT),
217
218 AM33XX_MUX(I2C0_SDA, OMAP_MUX_MODE0 | AM33XX_SLEWCTRL_SLOW | AM33XX_INPUT_EN | AM33XX_PIN_OUTPUT),
219
220 AM33XX_MUX(I2C0_SCL, OMAP_MUX_MODE0 | AM33XX_SLEWCTRL_SLOW | AM33XX_INPUT_EN | AM33XX_PIN_OUTPUT),
221
222 { .reg_offset = OMAP_MUX_TERMINATOR },
223 };

Now my commands are working fine. Thanks a lot. :slight_smile:

Regards
Srinivas