[PATCH] radeon: Release DDC i2c lines after probe

Benjamin Herrenschmidt benh at kernel.crashing.org
Sun Apr 3 17:54:53 PDT 2005

(Hui: any comment on this one ?)

This patch fixes support of recent Apple Cinema Display monitors.
Previously, we used to keep the SDA and SDL lines of the i2c "asserted"
after probing. This causes those monitor to shut down after a second or
so. This patch makes us "release" the line back to hi-z state (and thus
pulled high) after we are done probing a connector and fixes the problem
with Apple displays. (This should probably be applied to the stable
branch as well).

Index: xc/programs/Xserver/hw/xfree86/drivers/ati/radeon_driver.c
--- xc.orig/programs/Xserver/hw/xfree86/drivers/ati/radeon_driver.c	2005-04-04 10:18:39.000000000 +1000
+++ xc/programs/Xserver/hw/xfree86/drivers/ati/radeon_driver.c	2005-04-04 10:35:07.000000000 +1000
@@ -1006,6 +1006,9 @@
 	MonType = MT_NONE;
+    OUTREG(info->DDCReg, INREG(info->DDCReg) &
     if (*MonInfo) {
 	if ((*MonInfo)->rawData[0x14] & 0x80) {
 	    /* Note some laptops have a DVI output that uses internal TMDS,

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