Can I change pin mux while application working?

Kim,

The boot pins are latched at reset only and are not used after the boot is complete. you can change the pin Mux to use it as a SPI ENABLE pin in your application code.

Regards,

Rahul

Yes, you can change the pinmux while booting as long as it doesn`t affect the boot media that you are booting from.For example if you are booting from SPI flash, you can change the pinmux as long as you don`t affect the SPI CS, SIMO, SOMI, CLK PINs. On OMAPL137 there are multiple places where you can do this, After the ROM code executes the OMAPL137 runs an DSP user boot loader (UBL) that brings ARM out of reset and then the ARM runs a UBL that initializes UART, boot media and copies uboot. You can introduce the PIn MUX chnage in either of the two UBLs. Also, Uboot allows you to do low level configurations including PINMUX so it can be done there as well.

The kernel source and drivers assume that the device PINMUX is already been done so there is no provision to change PINMUX there but from application space if u mmap the SYSCFG register portion, you can change the pinmus by directly writing to the PINMUX registers from application space but is not recommended.

Regards,

Rahul

Hi,

The pin mux utility is generally used only to figure out availability of the pins. If you do create a header file you can use the #defines in the header file to assign those values to the pin mux registers in the system configuration registers.

If you want to configure it at the time of boot, you can provide them to the AISGen tool or in development you can use the values in the GEL files.

Regards,

Rahul