[U-Boot-Users] Please pull u-boot-83xx.git (I2C rework)

Tolunay Orkun listmember at orkun.us
Tue Nov 28 22:09:07 CET 2006

Wolfgang Denk wrote:
> In message <1164737878.31193.38.camel at saruman.qstreams.net> you wrote:
>>> Can you be more specific?  These two macros are defined in a variety of ways in 
>>> U-Boot.  Soft I2C is not used on any Freescale parts (AFAIK).
>> While it's not used on any Freescale evaluation boards, it could
>> certainly be implemented on boards with Freescale CPUs.  I'm not sure
>> why you'd bit-bang I2C if you have nice hardware controllers, but there
> ...because  the  bitbanging  code  is  much  smaller  and  easier  to
> implement and debug than the code that uses the HW controller?
>> may be situations where this makes sense.  On the other hand, I don't
>> know if SOFT_I2C and HARD_I2C can co-exist.
> No, theu=y are exclusive. But it should be possible to select any  of
> these interfaces.

How do we handle the case that there is one hard I2C interface and 
another soft I2C interface (bus) via a pair of GPIO port pins? I have a 
PPC405EP based custom board that has such a case and I was looking 
forward to enabling multiple I2C bus support in U-Boot via both SOFT_I2C 
as well as HARD_I2C defined.


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