L4Re GPIO

Erry Pradana Darajati pradana.erry at gmail.com
Tue Dec 30 03:11:12 CET 2014


>Hi
>This piece of code is missing the mapping of the GPIO4's MMIO region. For
your >client program to successfully access the GPIO chip you need to
create a virtual >device in IO's lua configuration file. Then you attach
this device to a virtual bus. In the >startup script you hand IO's
capability to that virtual bus to the 'vbus' cap of your >client. Then you
client can query its vbus to discover connected devices and their
>resources (see documentation of libvbus for reference). Then your client
can map the >GPIO's chip MMIO region.
>
>Best,
>Matthias.

Thank you for the explanation. I am reading through the libvbus doc right
now. I'm still not fully understand but if i conclude the method to access
the gpio of omap4460 in Pandaboard is : Define the res.mmio(address) in lua
.dev script. Make vbus capabilities in .cfg. Make a program that can access
GPIO via vbus with a client-server concept?
I'm sorry i'm not fully understand about this, but what is the server of
this client i am making.

Also, before i your email, i already 'porting' a omap4460-chip driver in io
module. and editing the .devs file so it matches with the memory of
omap4460 (The two file is attached). Is my step right, and after that what
should i do to be able to access it via my main program.
When i try to compile the omap44x2.c it give me error like attached below.
Is it because i'm not insert all of the virtual function in my program ?
because actually i am not really in my goal in the mean time.

I really appreciate and say biggest thanks with any of your suggestion and
answer

P.S : I am attaching my current main program just in case. And i still
access it directly. without

main2.c : http://pastebin.com/eZKqy1LE
omap44x2.c : http://pastebin.com/0hupnnyR
arm-omap4.devs : http://pastebin.com/pK6k7F5y
error output : http://pastebin.com/s2skR3wu
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