Re: parallel I/O ports & opend darin pins on MPC8xx

In message [off-list ref] you wrote:

quoted

Solution? What is so difficult about latching your output value in  a
variable?

What he's saying is that OTHER drivers read the input and then write
that value to the output.

I did understand this.

In his driver, he can latch the output through a variable, but that
won't affect what other

Obviously all drivers that may modify bits in this I/O port will have
to share the variable used to latch the value.

Yes, this may include modifying existing code in the UART or Ethernet
or other drivers.

Unless there is kernel support to alias the data in a memory variable
(and it doesn't sound like
there is), then this is going to continue to be a problem.  Might I

Don't make it unnecessary complicated. You don't need "kernel support
to alias the data in a  memory  variable".  This  is  really  not  so
difficult to implement yourself when you need it.


Best regards,

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
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