[U-Boot] Odd value for I2C_TIMEOUT in fsl_i2c.c

Wolfgang Denk wd at denx.de
Fri Sep 4 17:29:48 CEST 2009


Dear Timur Tabi,

In message <4AA12E52.2080403 at freescale.com> you wrote:
>
> > Wrong Question. I don't know enough about the I2C protocol. Why is
> > i2c_wait4bus necessary?
> 
> Ok, why is it necessary?

Maybe we should remove it, when nobody knows why it's needed.


> >> Kumar, any thoughts?  Is there something sneaky going on here, or did
> >> you just misinterpret the value of I2C_TIMEOUT?
> > 
> > I guess I2C_TIMEOUT might always have been misinterpeted.
> 
> I think the original code was correct, because it was counting clock ticks.

It cannot have been correct. get_timer() takes an argument of
milliseconds, i. e. a time. "(CONFIG_SYS_HZ / 4)" is a frequency,
i. e. not a time, but the inverse of it.

It is plain wront to write "250 per second" when you mean "250 milliseconds"

Best regards,

Wolfgang Denk

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