[RFC PATCH] Re: KMS:RV635:Radeon 3650HD graphics driver broken on a laptop when connected to a docking station and external display

Pasi Kärkkäinen pasik at iki.fi
Mon Jun 21 02:31:22 PDT 2010


On Mon, Jun 21, 2010 at 12:23:10PM +0300, Pasi Kärkkäinen wrote:
> On Sat, Jun 19, 2010 at 10:24:53PM +0300, Pasi Kärkkäinen wrote:
> > On Fri, Jun 18, 2010 at 09:45:22PM +0300, Pasi Kärkkäinen wrote:
> > > > > > >> >
> > > > > > >> > I wonder if that HDMI-0 is the key to the problem.. I don't have anything connected
> > > > > > >> > to the HDMI connector on the laptop. There's no HDMI connector on the dock, it's only in the laptop.
> > > > > > >>
> > > > > > >> Indeed that is the problem.  On your system the HDMI and DVI ports
> > > > > > >> share the same encoder and DDC line so they will both come up as
> > > > > > >> connected since the line is shared.  The driver used to check the edid
> > > > > > >> when the lines where shared and select HDMI or DVI based on the EDID,
> > > > > > >> but perhaps that got broken at some point.
> > > > > > >>
> > > > > > >
> > > > > > > Makes sense. Does some kernel option/parameter affect that?
> > > > > > 
> > > > > > No.  I'll check the code and see if I can figure out what's going on.
> > > > > > 
> > > > > 
> > > > > Ok, thanks!
> > > > > 
> > > > 
> > > > Hello,
> > > > 
> > > > I'll be near the dock tomorrow.. So if you have a chance of looking at this, and want me to test something,
> > > > I could do it on thursday/friday.
> > > > 
> > > 
> > > I just tried the latest Fedora 13 kernel (2.6.33.5-124.fc13.x86_64) and the latest 
> > > Fedora development (rawhide 2.6.34-43.fc14.x86_64) kernel, but the behaviour was the same.
> > > 
> > > Connecting display to the DVI connector makes the HDMI connector also show the same display, 
> > > breaking things..
> > > 
> > 
> > Here's a new log with drm.debug=4.. that's the biggest debug level that still allows me to grab
> > the whole dmesg log before it's overwritten by huge amount of debug messages.
> > 
> > Full dmesg log:
> > http://pasik.reaktio.net/fedora/bz593429/both-internal-and-external-displays-active/dmesg-with-drmdebug4.txt
> > 
> 
> Ok.. I did some debugging, and figured out how to make it work. Patch attached.
> I'm not sure if this is the correct method.. someone familiar with the code should review it.
> 
> 
> Some debugging information for my system (HP EliteBook 8530p):
> 
> > 
> > [drm] Radeon Display Connectors
> > [drm] Connector 0:
> > [drm]   VGA
> > [drm]   DDC: 0x7e40 0x7e40 0x7e44 0x7e44 0x7e48 0x7e48 0x7e4c 0x7e4c
> > [drm]   Encoders:
> > [drm]     CRT1: INTERNAL_KLDSCP_DAC1
> 
> connector->devices for VGA is: 1
> 
> > [drm] Connector 1:
> > [drm]   LVDS
> > [drm]   Encoders:
> > [drm]     LCD1: INTERNAL_KLDSCP_LVTMA
> 
> connector->devices for LVDS is: 2
> 
> > [drm] Connector 2:
> > [drm]   DVI-D
> > [drm]   HPD1
> > [drm]   DDC: 0x7e60 0x7e60 0x7e64 0x7e64 0x7e68 0x7e68 0x7e6c 0x7e6c
> > [drm]   Encoders:
> > [drm]     DFP1: INTERNAL_UNIPHY
> 
> connector->devices for DVI-D is: 8
> 
> > [drm] Connector 3:
> > [drm]   HDMI-A
> > [drm]   HPD2
> > [drm]   DDC: 0x7e60 0x7e60 0x7e64 0x7e64 0x7e68 0x7e68 0x7e6c 0x7e6c
> > [drm]   Encoders:
> > [drm]     DFP2: INTERNAL_UNIPHY
> 
> connector->devices for HDMI-A is: 128
> 
> 
> 
> The code in radeon_connectors.c in radeon_dvi_detect():
> 
> 	/* multiple connectors on the same encoder with the same ddc line
> 	 * This tends to be HDMI and DVI on the same encoder with the
> 	 * same ddc line.  If the edid says HDMI, consider the HDMI port
> 	 * connected and the DVI port disconnected.  If the edid doesn't
> 	 * say HDMI, vice versa.
> 	 */
> 	if (radeon_connector->shared_ddc && (ret == connector_status_connected)) {
> 		struct drm_device *dev = connector->dev;
> 		struct drm_connector *list_connector;
> 		struct radeon_connector *list_radeon_connector;
> 		list_for_each_entry(list_connector, &dev->mode_config.connector_list, head) {
> 			if (connector == list_connector)
> 				continue;
> 			list_radeon_connector = to_radeon_connector(list_connector);
> 			if (radeon_connector->devices == list_radeon_connector->devices) {
> 				if (drm_detect_hdmi_monitor(radeon_connector->edid)) {
> 					if (connector->connector_type == DRM_MODE_CONNECTOR_DVID) {
> 						kfree(radeon_connector->edid);
> 						radeon_connector->edid = NULL;
> 						ret = connector_status_disconnected;
> 					}
> 				} else {
> 					if ((connector->connector_type == DRM_MODE_CONNECTOR_HDMIA) ||
> 					    (connector->connector_type == DRM_MODE_CONNECTOR_HDMIB)) {
> 						kfree(radeon_connector->edid);
> 						radeon_connector->edid = NULL;
> 						ret = connector_status_disconnected;
> 					}
> 				}
> 			}
> 		}
> 	}
> 
> 
> Ok, so at least on my system the "if (connector == list_connector)" will SKIP the connector
> that actually would match in "if (radeon_connector->devices == list_radeon_connector->devices)",
> and thus the drm_detect_hdmi_monitor() is never called.
> 
> My patch removes that "if (connector == list_connector)" check and fixes the problem on my system.
> Is this the correct way to do it? 
> 
> radeon-fix-shared_ddc-dvi-hdmi-edid-detection.patch:
> 	- allow checking against all connectors to be able to properly detect shared_ddc dvi/hdmi displays
> 	- patch applies to 2.6.33.5, 2.6.34 and 2.6.35-rc3. Tested with Fedora 13 2.6.33.5-124.fc13.x86_64.
> 	- Signed-off-by: Pasi Kärkkäinen <pasik at iki.fi>
> 

And actually attached now :)

-- Pasi


> 
> Thanks!
> 
> Btw. I still have some other problems related to lid open/closed detection for the LVDS but I'll open another thread about that :) 
> 
> -- Pasi
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
-------------- next part --------------
A non-text attachment was scrubbed...
Name: radeon-fix-shared_ddc-dvi-hdmi-edid-detection.patch
Type: text/x-diff
Size: 687 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20100621/cffd3801/attachment.patch>


More information about the dri-devel mailing list