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Date: Sun, 11 Mar 2012 18:24:57 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: santosh prasad nayak <santoshprasadnayak@gmail.com>,
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Subject: Re: [PATCH] Video : Amba: Use in_interrupt() in clcdfb_sleep().
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> As I've said, if we aren't going to use this, then the only solution is
> to completely omit the msleep() there and just say "sod you to running
> anything else for 20ms while this driver busy-spins."  That's
> ultimately the safe thing to do, and at the moment I see no other
> alternative there.

Anyone having this argument is also right now peeing into the wind. Quite
a few console drivers do this including some the big name x86 ones. We
don't seem to be getting any resulting problem reports.

Architecturally we really need a way to help console drivers separate the
civilised acceleration friendly, lock friendly output paths from printk.
That's the real fix, but a whole different matter to solve cleanly.

Alan