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Subject: Re: [Linux-fbdev-devel] Type confusion in fbcon
From: "David S. Miller" <davem@redhat.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Russell King <rmk@arm.linux.org.uk>,
       James Simmons <jsimmons@infradead.org>,
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       Linux Frame Buffer Device Development 
	<linux-fbdev-devel@lists.sourceforge.net>
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On Mon, 2002-12-23 at 01:18, Geert Uytterhoeven wrote:
> That's because originally there was no fix.line_length field, and the line
> length was derived from var.xres_virtual and var.bits_per_pixel.
> 
> With some hardware, the line length must be a multiple of 32 or 64 bits, and we
> needed a way to specify that, so fix.line_length was introduced. If it was
> zero, user code should fallback to the old behavior.

And with some cards, the line length is constant.  Ie. to get to
"X, Y + 1" for a given "X, Y" you add a constant to your current
frame buffer pointer.

That is what fix.line_length is for right?