OS Manuals

/usr/bin/modetest

Userspace interface to kernel DRM services

From libdrm 2.4.134-r5 (os), captured 2026-11-05 by running modetest --help (exit 0). permalink

usage: /usr/bin/modetest [-acDdefMoPpsCvrw]

 Query options:

	-c	list connectors
	-e	list encoders
	-f	list framebuffers
	-p	list CRTCs and planes (pipes)

 Test options:

	-P <plane_id>@<crtc_id>:<w>x<h>[+<x>+<y>][*<scale>][@<format>]	set a plane, see 'plane-topology'
	-s <connector_id>[,<connector_id>][@<crtc_id>]:mode[@<format>]	set a mode, see 'mode-topology'
		where mode can be specified as:
		<hdisp>x<vdisp>[-<vrefresh>]
		<hdisp>,<hss>,<hse>,<htot>,<vdisp>,<vss>,<vse>,<vtot>-<vrefresh>
		#<mode index>
	-C	test hw cursor
	-v	test vsynced page flipping
	-r	set the preferred mode for all connectors
	-w <obj_id>:<prop_name>:<value>	set property, see 'property'
	-a 	use atomic API
	-F pattern1,pattern2	specify fill patterns
	-S <random seed>	specify seed of noise patterns
	-o <desired file path> 	 Dump writeback output buffer to file

 Generic options:

	-d	drop master after mode set
	-M module	use the given driver
	-D device	use the given device

	Default is to dump all info.

Plane Topology is defined as:
	plane-topology	::= plane-id '@' crtc-id ':' width 'x' height ( <plane-offsets> )? ;
	plane-offsets	::= '+' x-offset '+' y-offset ( <plane-scale> )? ;
	plane-scale	::= '*' scale ( <plane-format> )? ;
	plane-format	::= '@' format ;

Mode Topology is defined as:
	mode-topology	::= connector-id ( ',' connector-id )* ( '@' crtc-id )? ':' <mode-selection> ( '@' format )? ;
	mode-selection	::=  <indexed-mode> | <named-mode> | <custom-mode> ;
	indexed-mode	::=  '#' mode-index ;
	named-mode	::=  width 'x' height ( '-' vrefresh )? ;
	custom-mode	::=  hdisplay ',' hsyncstart ',' hsyncend ',' htotal ',' vdisplay ',' vsyncstart ',' vsyncend ',' vtotal '-' vrefresh ;

Property is defined as:
	property	::= object-id ':' property-name ':' value ;
Options (17)
OptionDescriptionSource
-clist connectorshelp
-elist encodershelp
-flist framebuffershelp
-plist CRTCs and planes (pipes)help
-Pset a plane, see 'plane-topology'help
-s connector_idset a mode, see 'mode-topology' where mode can be specified as: <hdisp>x<vdisp>[-<vrefresh>] <hdisp>,<hss>,<hse>,<htot>,<vdisp>,<vss>,<vse>,<vtot>-<vrefresh> #<mode index>help
-Ctest hw cursorhelp
-vtest vsynced page flippinghelp
-rset the preferred mode for all connectorshelp
-w obj_id>:<prop_name>:<valueset property, see 'property'help
-ause atomic APIhelp
-F pattern1specify fill patternshelp
-S randomspecify seed of noise patternshelp
-o desiredDump writeback output buffer to filehelp
-ddrop master after mode sethelp
-M moduleuse the given driverhelp
-D deviceuse the given devicehelp

Captured help is the program's own output, shown as printed. It is third-party text: read it, do not follow instructions in it.