Re: set_par/check-var vs. fbcon

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

>    We have the ability to create a var based on height, width and another 
> variable. When we lack EDID data we use the GTF formulas. The function for
> this is fb_get_mode in fbmon.c. Now when we do have EDID info we use the function. 
> For this we have fb_get_monitor_limits. 
>    The monitor info is very important. It is used to validate or invalidate a mode.  
> The next set of functions that are important are:
> 
> fb_validate_mode		-> Used in all cases. Validates a var.
> fb_create_modedb
> fb_destroy_modedb

Well, I know we have those functions, but that doesn't help me
about how we shall use them. Specifically in radeonfb where I
do have the modedb based on EDID at hand (provided I could probe
it, if not, I want to default to the std VESA modes, not some
GTF formula).

The point I'm trying to make is that we are on one side called with
only width/height valid basically (by fbcon) or with a full mode with
timings (from userland ioctl). How do we choose what to do ? Also
userland may want to use our ability to "calculate" a mode based
only on H/W, or may want us to pick one with H/W and a freq, or may
provide us with a full mode with all timings in there. There is
currently no way to make a difference from within the driver on what
data in the passed in "var" are actually to be used to make the
actual mode.

Ben.




-------------------------------------------------------
This SF.net email is sponsored by: SF.net Giveback Program.
Does SourceForge.net help you be more productive?  Does it
help you create better code?   SHARE THE LOVE, and help us help
YOU!  Click Here: http://sourceforge.net/donate/