Messages in this thread | | | Date | Wed, 18 Nov 2009 17:52:02 +0100 | From | Jean Delvare <> | Subject | Re: yield() in i2c non-happy paths hits BUG under -rt patch |
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On Wed, 18 Nov 2009 17:28:53 +0100, Leon Woestenberg wrote: > On Wed, Nov 18, 2009 at 2:05 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote: > > Our timers are very efficient and some day we will need to make jiffies a > > function and stop the timer ticking for best performance. At that point > > timers are probably the most efficient way to do much of this. > > The problem with I2C bitbanged is the stringent timing, we need a way > to have fine-grained sleeping > mixed with real-time tasks in order to make this work.
FWIW, the problem that was initially reported has nothing to do with this. i2c-algo-bit used mdelay() during transactions, not yield(). yield() is used only in once place, _between_ transactions attempts. There are no strict timing constraints there.
-- Jean Delvare
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