From b5a8a71e64c76b8dd42962cbd7984215c6ce4aa8 Mon Sep 17 00:00:00 2001

From: Keith Packard <[email protected]>

Date: Sat, 17 Mar 2007 17:26:11 -0700

Subject: [PATCH] Remove extra (and wrong) I2C ByteTimeout setting in DDC code.

The DDC code sets the I2C timeouts to VESA standards, except that it had an

extra setting of the ByteTimeout value which was wrong (off by a factor of

50). Removing this should help DDC work on many more monitors. Note that the

Intel driver duplicated these settings, along with the error. Yay for cult

and paste coding.

---

 hw/xfree86/ddc/xf86DDC.c |    1 -

 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/hw/xfree86/ddc/xf86DDC.c b/hw/xfree86/ddc/xf86DDC.c

index 4ce585c..0f24c52 100644

--- a/hw/xfree86/ddc/xf86DDC.c

+++ b/hw/xfree86/ddc/xf86DDC.c

@@ -344,7 +344,6 @@ DDCRead_DDC2(int scrnIndex, I2CBusPtr pB

 	dev->ByteTimeout = 2200; /* VESA DDC spec 3 p. 43 (+10 %) */

 	dev->StartTimeout = 550;

 	dev->BitTimeout = 40;

-	dev->ByteTimeout = 40;

 	dev->AcknTimeout = 40;

 	dev->pI2CBus = pBus;

-- 

1.4.1

From 720f302d241e88e6e9f2962207da1aa9a79728b7 Mon Sep 17 00:00:00 2001

From: Keith Packard <[email protected]>

Date: Sat, 17 Mar 2007 20:14:05 -0700

Subject: [PATCH] Slow down DDC I2C bus using a RiseFallTime of 20us for old monitors.

This time value makes the bus run slowly enough for even the least reliable

of monitors. Thanks to Pavel Troller for finding the necessary change.

---

 hw/xfree86/ddc/xf86DDC.c |    6 ++++++

 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/hw/xfree86/ddc/xf86DDC.c b/hw/xfree86/ddc/xf86DDC.c

index 0f24c52..8080c8d 100644

--- a/hw/xfree86/ddc/xf86DDC.c

+++ b/hw/xfree86/ddc/xf86DDC.c

@@ -337,6 +337,12 @@ DDCRead_DDC2(int scrnIndex, I2CBusPtr pB

     unsigned char *R_Buffer;

     int i;

+    /*

+     * Slow down the bus so that older monitors don't 

+     * miss things.

+     */

+    pBus->RiseFallTime = 20;

+    

     if (!(dev = xf86I2CFindDev(pBus, 0x00A0))) {

 	dev = xf86CreateI2CDevRec();

 	dev->DevName = "ddc2";

-- 

1.4.1