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Interrupt routine accessing i2c bus
I am trying to write a serial driver for the philips
16is7xx i2c/rs232 bridge. These devices are basically
a 16550 serial port with an i2c bus rather than a
conventional address/data bus.
Here is my problem:
The i2c driver routines use up(&xxx) / down(&xxx)
semaphores so they cannot be accessed in interrupt
context. Both ISR's and tasklets both run in
interrupt context so the i2c drivers need to accessed
some other way.
I was thinking of creating a task with
wait_for_completion(&xxx) and having the ISR do a
complete(&xxx) to wake the task. However I believe
(please correct me if I'm wrong.... I'm not to sure
about this) that the delay between the complete(&xxx)
and the waiting task could be tens of milliseconds.
Even with a 64 byte FIFO it is going miss receive
characters at anything faster than 9600b.
Does anyone have any suggestions on how I should do
the bottom half of the ISR so I don't miss characters?
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