parallel I/O ports & opend darin pins on MPC8xx

[Wolfgang Denk]

In message <3F0C6C0C.8040306 at earthlink.net> you wrote:
>
> >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

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