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From: tglx@linutronix.de (Thomas Gleixner)
To: "Eisenhut, Daniel (MED)" <Daniel.Eisenhut@med.ge.com>,
	"'linux-mtd@lists.infradead.org'" <linux-mtd@lists.infradead.org>
Date: Wed, 26 May 2004 23:26:29 +0200
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Subject: Re: Accessing an MTD device from kernel space
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On Wednesday 26 May 2004 23:21, Eisenhut, Daniel (MED) wrote:
> To list,
>
> I've successfully setup MTD devices for our NOR flash chips and
> everything is working great from userspace.  But I have a need to access
> the NOR flash from within kernelspace, such as in a /proc entry.
>
> What is the best way to access the flash from within the kernel?  The
> only way I've be able to so far is to just dereference a pointer
> pointing to the flash address.  But this creates two issues (that I know
> about):
>
> 1. A race condition between my proc entry that reads the flash and
> another process using the MTD device.
>
> 2. The MTD device does not always leave the flash chip in read mode.
>
> Is there anything setup in the current MTD code to allow access from
> within the kernel?

Just use the mtd API which is used from fs drivers and anything else which=
=20
accessed the mtd devices from kernel space

mtd->read(....), mtd->erase(...)=20

=2D-=20
Thomas
________________________________________________________________________
Steve Ballmer quotes the statistic that IT pros spend 70 percent of their=20
time managing existing systems. That couldn=E2=80=99t have anything to do w=
ith=20
the fact that 99 percent of these systems run Windows, could it?
________________________________________________________________________
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