Re: [U-Boot-Users] [PATCH 1/1] Fix I2C for m547x/548x and m5445x processors.

7 Jul 2008


      In message 1215447465.12657.15.camel@localhost you wrote:
...
I just extended the fsl_i2c.c driver that already uses a precomputed
Yes, I know. I never understood what such a  complicated  driver  for
sich  a  simple  protocol  was  good  for,  especially as we don't do
multimegabytepersecond transfers over such a bus.
...
table to setup the fsl i2c. I haven't invented these values but just
copied from the 547x and 5445x manuals. Furthermore, the h/w i2c is more
accurate that the simple bitbanging.
Accurate? There is no requirement to be "accurate"  anywhere  in  the
I2C  protocol.  It  is  a simple, brain-dead protokol where timing is
highly uncritical. And given that we need it to read a few bytes from
EEPROM or RTC or similar I really see no  benefit  in  using  such  a
complicated driver.
Best regards,
Wolfgang Denk
-- 
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