Created attachment 24366 [details]
Xorg.0.log showing defect

The Composite output (CVBS) type is not recognized on SDVO TV ports. 
See line (WW) intel(0): SDVOB: Unknown SDVO output type (0x0400) in xorg.0.log
This results in plain old TV set not working through SDVO.


System environment:
-- chipset: 945GC
-- system architecture: i686 32 bits
-- xf86-video-intel: git commit #:375b2e40fcb17e94538a75392950e2533c1bb031
-- xserver: xorg-server-1.6.0
-- mesa: git commit #: 2002e03a5232c54988161cb629966bdce19d35de
-- libdrm: git commit #: c9cfeaa5542e08381a8144d0a5bd96036a19082f
-- kernel: 2.6.28.8
-- Linux distribution: Zenwalk 6.0.0
-- Machine or mobo model: Asus P5GC-MX
-- Display connector: VGA(DB-15) + Composite BNC Connector

Reproducing steps:

Boot the machine with attached xorg.conf, a regular VGA monitor on the DB-15 and a NTSV TV set on the the Composite BNC connector.
Nothing plugged into the DVI connector.
Would expect the VGA and the TV to side by side in a desktop spanning the two monitors.
Only the VGA monitor is being used in the desktop and the TV does not get any signal.
xrandr reports TV connector as "Unknown-1" instead of TV-1 (see attached log)

Additional info:

Using an Advantech Add2 card with Chrontel CH7021 on SDVO-B (Composite) and Chrontel CH7307 on SDVO-C (DVI)

This issue seems to be related to the fact the case where flag = SDVO_OUTPUT_CVBS0 in i830_sdvo_output_setup is not supported.
In fact, adding the following code after the "else if (flag & SDVO_OUTPUT_SVID0)" block makes the thing works just fine.


    else if (flag & SDVO_OUTPUT_CVBS0)
    {
	dev_priv->controlled_output = SDVO_OUTPUT_CVBS0;
	output->subpixel_order = SubPixelHorizontalRGB; /* XXX */
	name_prefix="TV";
	dev_priv->is_tv = TRUE;
	intel_output->needs_tv_clock = TRUE;
    }