Hi The series adds support for changing the order of the displays defined by DT display aliases. The motivation to do such a thing is that for example the fb emulation is treating the first display/crtc as the 'main' display and will create the fb emulation based on the first display's properties. There are many custom applications using DRM directly and they assume that the first connector is the 'main' display. Afaik weston provides no means either to change the 'main/preferred' display. It should be the work of user space application (except the fb emulation) to somehow deal with the 'main' display selection for their needs, but unfortunately they are not capable of diong so for some reason. We have boards with LCD panel and HDMI for example and in DT the LCD is set as display0, but in certain useage scenarios it is desired to have the HDMI as the 'main' display instead of the LCD. With the kernel cmd line parameter it is possible to change the pre defined order without recompiling the kernel/DT. If the board have two active displays: 0 - LCD 1 - HDMI then: omapdrm.displays=0,1 - represents the original order (LCD, HDMI) omapdrm.displays=1,0 - represents reverse order (HDMI, LCD) omapdrm.displays=0 - only the LCD is enabled omapdrm.displays=1 - only the HDMI is enabled omapdrm.displays=-1 - disable all displays The first 6 patch of the series is doing some generic clean up and prepares the code so the display ordering is going to be easy to add. Regards, Peter --- Peter Ujfalusi (7): drm/omap: Use devm_kzalloc() to allocate omap_drm_private drm/omap: Allocate drm_device earlier and unref it as last step drm/omap: Manage the usable omap_dss_device list within omap_drm_private drm/omap: Separate the dssdevs array setup from the connect function drm/omap: Do dss_device (display) ordering in omap_drv.c drm/omap: dss: Remove display ordering from dss/display.c drm/omap: Add kernel parameter to specify the desired display order drivers/gpu/drm/omapdrm/dss/display.c | 15 +-- drivers/gpu/drm/omapdrm/dss/omapdss.h | 3 - drivers/gpu/drm/omapdrm/omap_drv.c | 244 ++++++++++++++++++++++++---------- drivers/gpu/drm/omapdrm/omap_drv.h | 3 + 4 files changed, 183 insertions(+), 82 deletions(-) -- 2.14.1 Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel