new am335x drivers

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

Hello,
I've ported/written 2 new drivers for the TI AM335x SoC as found on
the beadlebone:
- a driver for the Control module. Other drivers needs to call into it
  to configure I/O pin multiplexor (e.g. is it a GPIO or used by a
  I2C module), among others. if_cpsw.c already have a hack to read
  Control module registers to get the ethernet address; I patched
  it to use the new driver to get the value. This is from FreeBSD
- a driver for the I2C module; tested with the onboard serial eeprom:
  # dd if=/dev/seeprom0  bs=1 count=24 | od -xc  
  0000000     55aa    ee33    3341    3533    4f42    454e    3030    3641
  252   U   3 356   A   3   3   5   B   O   N   E   0   0   A   6
  0000020     3734    3231    4242    3030                                
    4   7   1   2   B   B   0   0                                
  (this uses the Control module driver to make sure the appropriate
   pads are configured for I2C0).
  This needs some more work, e.g. to use interrupts.

This is available in ftp://ftp-asim.lip6.fr/outgoing/bouyer/beaglebone/,
there is a tgz with the new files and a patch for existing files that need
to be changed.

As I'm not familiar with ARM hardware, I'm not sure the names I've chosen
make sense. I assumed that TI AM335x is omap2, but I'm not sure about that.
I called the Control module driver omap2scm. It should be useable at last
for some omap4 devices too (from the freebsd sources) but we also have a
omap3_scm driver, which seems to be for something completely different.

I called the i2c module driver omap2iic. There is another omap i2c driver
(omapiic) for omap3. The modules looks different enough (different register
map, and I suspect different features) to have 2 different drivers.

Does it make sense, or would some other names be better ?

After this is commited, I'll look at adding interrupt support to the iic
driver, and will start working on support of the TPS65217 power controller
(which requires a working i2c).

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--