Re: hdparm for lib_pata

[Jeff Garzik]

Alan wrote:
> > Userspace PIO mode changes are NOT a good idea,
>
> I would disagree there, but they are not high priority. We do need to
> allow set_features/xfer but we need to snoop it and mode set properly
> around it. There are cases you want to control this, more so admittedly
> for DMA speeds.

*Bingo*

That's the entire reason why libata does not support hdparm changing 
modes, etc.:  there is a lot involved in allowing random SET FEATURES - 
XFER MODE commands from userspace.  In some cases you have to stop all 
traffic on ports B,C,D,... in order to change the speed on port A.

	Jeff



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