[i2c] [PATCH] Add a new-style driver for most I2C EEPROMs

Wolfram Sang w.sang at pengutronix.de
Mon Apr 21 11:17:46 CEST 2008


Trent Piepho wrote:

> Oh, of course.  I had ignored the retries because it seemed like a bad
> idea.  If the timeout is based on time, why does it matter how many tries
> there were?
Because then you have a guaranteed number of tries, even if the timeout 
value was reached due to some reason.

> Still, if you want to wait at least 25 ms, on a HZ=1000 system you might
> wait only 3 ms.  
I'm sorry, I fail to see this. If there are more than three retries, 
then there is still the time_before-condition which keeps the loop 
running until the timeout is reached, no?

> And on a HZ=100 system, you'll wait at least 60 ms when
> the timeout only needed to be 25 ms.
Yes, because there is this policy to retry at least three times. Maybe 
it is an idea to introduce a module parameter which lets the user select 
a suitable retry parameter?

    Wolfram

-- 
   Dipl.-Ing. Wolfram Sang | http://www.pengutronix.de
  Pengutronix - Linux Solutions for Science and Industry




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