Re: Synchronization between ISR and IST - I2C Based device

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and in this case that MUST be a single instance driver for the dual
channel device.

No. That is what I am trying to point. It is possible and not very
difficult to have a driver instance for each device, provided the driver is
prepared to this situation.

It's vastly more complicated to implement a driver such that it uses shared
global data and synchronization mechanisms for a single IST. In this case
there MUST be only one IST as THAT is what MUST make the determination of
which specific channel caused the interrupt as the ISR can't do that. So
trying to create 2 driver instances with a single IST just complicates the
driver implementation. And in the end that approach does not add anything
beyond what a simple IOCTL that sets the channel number for an open context
gives you. So, yes, it is possible to implement it as multiple driver
instances but it would be a complete waste of time and effort to do so and
dramatically increase your development time and costs.



--
Steve Maillet
EmbeddedFusion
www.EmbeddedFusion.com
smaillet at EmbeddedFusion dot com


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