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

Wolfgang Denk
2008-07-07T18:02:17Z

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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