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From: Daniel Braniss <danny@cs.huji.ac.il>
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Subject: help with coding a loadable kernel module
Date: Fri, 17 Apr 2015 11:04:04 +0300
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Hi,
I know I=E2=80=99m embarking on a dangerous trip, but I want to use a =
Raspberry Pi
and or a BeagleBone to read (and write) RFID cards.
Since a driver is needed to use the spibus, I have 2 options while
developing:
1- write a conventional driver module
    means cross compiling, generating a new kernel, making a new image,
    writing a SD card, etc, etc
2- make it a loadable module
    cross compile,via NFS load/unload=20

2 seems the logical path, but I=E2=80=99m getting entangled trying to =
use
   the spibus, while with 1 there are several drivers I can use to
   learn from.

So before I give up on option 2, is there some examples/help?

I should point out that I have no experience (yet) with arm/spi/fdt
and so option 2 will make the trial and error faster :-)

thanks

	danny