Shared GPIO pin

Hi,

     Can you tell me where exactly you are trying to modify the pin mux settings. Uboot, kernel or application. It do have different pin mux settings in each level. 

Regards

Faizel

Hi,

we try to change in application. The pin simply must drive a LED.

I have also tested to toggel this pin in Uboot, but we only got 1,6V at output.

The setting seems not to be correct.

Hi,

     Try using sysfs method from linux. Please don't load the dsp firmwares as those firmware changes the pin mux settings. 

http://processors.wiki.ti.com/index.php/TI81XX_PSP_GPIO_Driver_User_Guide

For pin muxing from the kernel edit the following file

arch/arm/mach-omap2/devices.c Change omap mux init call specific to that pin.

Regards

Faizel

Thanks for Your replay.

First I did try to set in /uboot/ /board/ti/ti8168_dvr/dvr.c  MUX_VAL(SPI_SCS3, 0x12) In this case I can set the LED in uboot but  uboot hangs if MUX_VAL(SPI_SCS3 ) is set.

Currently will try to setup the GPIO mux in linux kernel but I not sure where to do this in devices.c

Hi,

     If  you want to do the pinmux settings from uboot then you can use the mw utility from u-boot (if you know the registers to modify)

In devices.c file please follow any call, for example

omap_mux_init_signal("mmc_dat1_sdirq", OMAP_PULL_UP);

Change first and second argument specific to your requirement. You need to find out the pin/pad in the code where you want to modify the pin mux settings.

Regards

Faizel

Hello,

The below wiki page might be also in help:

http://processors.wiki.ti.com/index.php/TI81XX_PSP_User_Guide#TI816X_3

Regards,
Pavel

Hi Faizel and Pavel,

thanks for Your reply.

Lastbutnot least I found a solution with  "omap_mux_init_signal("gp1_io22", OMAP_PIN_OUTPUT)"  in devices.c.

This works for us.

But for me it is not clear why we can not set this pin mux in uboot, any idea ?

Best regrads Holger

Thanks for the advice, it works.

Best regards Holger