: Fix radeon blanking return value.
PATCH 1/1 : Fix radeon blanking return value.
If you'll recall, over a year ago, I pointed out that the current Radeon driver erroneously returns -EINVAL for valid blanking codes, here is a link to that thread:
http://lkml.org/lkml/2006/1/28/6
No other driver does this, and it confuses the X server into thinking that the device does not support blanking properly.
As a result I have to switch to a console VC and back to the X server to unblank the screen, which is rediculious.
I've had to do this for more than 3 years and I'm really tired of this problem still being around :-)
I looked again and there is simply no reason for the Radeon driver to return -EINVAL for FB_BLANK_NORMAL. It claims it wants to do this in order to convince fbcon to blank in software, right here:
if (fb_blank(info, blank)) fbcon_generic_blank(vc, info, blank);
to software blank the screen. But it only causes that to happen in the FB_BLANK_NORMAL case.
That makes no sense because the Radeon code does this:
val |= CRTC_DISPLAY_DIS;
in the FB_BLANK_NORMAL case so should be blanking the hardware, and there is therefore no reason to SW blank by returning -EINVAL.
Therefore I propose we finally apply the following patch. No other fbdev driver does this madness, and as I've shown above there is no justification for the behavior at all :-)
drivers/video/aty/radeon_base.c +1 -2
@@ -1032,8 +1032,7 @@ int radeon_screen_blank(struct radeonfb_info *rinfo, int blank, int mode_switch)break ; } -/* let fbcon do a soft blank for us */ -return (blank ==FB_BLANK_NORMAL ) ? -EINVAL :0 ; +return 0 ; }static int radeonfb_blank (int blank,struct fb_info *info)
Quoted 27 lines · David Miller
If you'll recall, over a year ago, I pointed out that the current Radeon driver erroneously returns
-EINVALfor valid blanking codes, here is a link to that thread:http://lkml.org/lkml/2006/1/28/6No other driver does this, and it confuses the X server into thinking that the device does not support blanking properly.
As a result I have to switch to a console VC and back to the X server to unblank the screen, which is rediculious.
I've had to do this for more than 3 years and I'm really tired of this problem still being around :-)
I looked again and there is simply no reason for the Radeon driver to return
-EINVALforFB_BLANK_NORMAL. It claims it wants to do this in order to convince fbcon to blank in software, right here:if (fb_blank(info, blank)) fbcon_generic_blank(vc, info, blank);to software blank the screen. But it only causes that to happen in the
FB_BLANK_NORMALcase.That makes no sense because the Radeon code does this:
Quoted 8 lines
val |= CRTC_DISPLAY_DIS;in the
FB_BLANK_NORMALcase so should be blanking the hardware, and there is therefore no reason to SW blank by returning-EINVAL.Therefore I propose we finally apply the following patch. No other fbdev driver does this madness, and as I've shown above there is no justification for the behavior at all :-)
This was before radeonfb did not fully differentiate each blanking levels. Currently, it is fixed, so I agree with this patch.
Quoted 2 lines
Signed-off-by David S. Miller <[email protected]>
Tony