Re: [PATCH] fbdev: workaround for broken X servers

On Wednesday 03 November 2004 11:26, Ville Syrjälä wrote:

On Wed, Nov 03, 2004 at 01:13:39PM +1100, Benjamin Herrenschmidt wrote:

quoted

Hi !

+	/* Workaround for broken X servers */
+	if (blank > VESA_POWERDOWN)
+		blank = VESA_POWERDOWN;
+
 	if (info->fbops->fb_blank && !info->fbops->fb_blank(blank, info))
 		return 0;

This goes against documented behaviour (see fb.h). Also drivers/char/vt.c
seems to agree with fb.h, as do at least atyfb and matroxfb. I also used
the vesa level+1 convention in DirectFB. So AFAICS this patch would
confuse console power management, XFree86/X.Org, DirectFB and some fb
drivers.

True enough. The convention is if the display is active, then suspend. If
it is suspended, then powerdown.  And if already powered down, then do
nothing.  It does so by by sending a blank flag of VESA_POWERDOWN + 1.

This is the convention used by the vt layer, I don't what is used by user apps.
The above patch won't break console power management as the console calls
fbcon_blank(), not fb_blank().

Tony




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