ApplePanels and backlight values
ApplePanels and backlight values
- Subject: ApplePanels and backlight values
- From: Benjamin Herrenschmidt <email@hidden>
- Date: Mon, 07 Feb 2005 16:33:59 +1100
Hi !
ApplePanelA builds a ramp of panel values based on a list of panels
(min/mid/max values) contained in it's property list.
On most panels, these values go up to 0xff for the max backlight
value.
I've traced the ATI driver and it seems that it will blast the value
passed by the control call directly into the appropriate LVDS control
register (doesn't apply it's own scaling, only eventually inverts).
My question is, is it safe to actually uses values up to 0xff ? It seems
that the ApplePanelA::doIntegerSet() method is passing the value as-is
to the driver (which is writing it as-is to the hw). So we end up using
actual backlight value up to the HW maximum of 0xff... However, when I
played with that back in the OS 9 days, I noticed the system was never
writing the full 0xff to the LVDS modulation in the chip (usually max'ed
it out around 0xd9). Unless I've missed something, the plist for that
same panel (family 8) are all ending up with 0xff for max.
I just want to make sure I won't damage any HW ....
Regards,
Ben.
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Darwin-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden