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From: Hector Martin <hector@marcansoft.com>
To: linux-acpi@vger.kernel.org
Subject: Locking out AML code
Date: Tue, 07 Jul 2009 16:08:02 +0200	[thread overview]
Message-ID: <4A5356C2.3090608@marcansoft.com> (raw)

I'm writing a driver to access some EC-related functionality on some
Acer laptops. This uses a separate IO port interface and cannot be done
using the standard ec_read / ec_write ACPI functions. The DSDT also
accesses these IO ports for a few things (most notably display
brightness and some WMI methods). Is there a lock I can hold (from
outside the ACPI subsystem) that will lock out AML method execution
while I poke the hardware?

FWIW, the Windows drivers from Acer also access those IO ports directly
(from userspace, no less, with a dumb kernel driver to provide port I/O
to userspace and in the process introduce a huge security hole of
course). There is no way of talking to this hardware via DSDT methods.

-- 
Hector Martin (hector@marcansoft.com)
Public Key: http://www.marcansoft.com/marcan.asc


             reply	other threads:[~2009-07-07 14:08 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-07 14:08 Hector Martin [this message]
2009-07-07 14:29 ` Locking out AML code Lin Ming

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