Beagleboard RevC Expansion Header

Hi,

beagleboard has expansion header and from bbsrm_6 it says there are
mux control register to select different option for this header. it
says option a, b, c. Is this mux control option exposed in linux
kernel? I want to make all pin on expansion header become gpio except
for fixed function pin like nReset, regen, etc. Is this possible?

Thank you,
Yemek

Hi,

beagleboard has expansion header and from bbsrm_6 it says there are
mux control register to select different option for this header. it
says option a, b, c. Is this mux control option exposed in linux
kernel? I want to make all pin on expansion header become gpio except
for fixed function pin like nReset, regen, etc. Is this possible?

Short answer is -
Yes, the mux control setup is exposed in Linux. You will likely have to add
some defines/enums and add a macro call. You can certainly configure them to
be all GPIO if it is not fixed function. To be safe, you probally want to do
this in Linux to avoid any surprises with the different U-boot's. Note that
RevC will require a slightly different code to select the functionality.

Long answer -
I have a write up about this:
http://www.hy-research.com/omap3_pinmux.html