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Date: Tue, 8 Jan 2008 10:42:14 -0600
From: Scott Wood <scottwood@freescale.com>
To: Misbah khan <misbah_khan@engineer.com>
Subject: Re: How to write a device driver in such a fashion .????
Message-ID: <20080108164214.GB4949@loki.buserror.net>
References: <14660018.post@talk.nabble.com> <14682271.post@talk.nabble.com>
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On Mon, Jan 07, 2008 at 08:31:10PM -0800, Misbah khan wrote:
> 
> using mmap() in application to access the h/w is only possible if  the device
> memory is mapped in the kernel virtual memory how come we directly map to
> the physical memory to virtual from user space ??? 

No, /dev/mem takes physical addresses, not kernel virtual.

-Scott