NAME¶
drmModeGetResources - retrieve current display configuration information
SYNOPSIS¶
#include <xf86drmMode.h>
typedef struct _drmModeRes {
int count_fbs;
uint32_t *fbs;
int count_crtcs;
uint32_t *crtcs;
int count_connectors;
uint32_t *connectors;
int count_encoders;
uint32_t *encoders;
uint32_t min_width, max_width;
uint32_t min_height, max_height;
} drmModeRes, *drmModeResPtr;
drmModeResPtr drmModeGetResources(int fd);
DESCRIPTION¶
This function will allocate, populate, and return a drmModeRes structure
containing information about the current display configuration.
The
count_fbs and
fbs fields indicate the number of currently
allocated framebuffer objects (i.e. objects that can be attached to a given
CRTC or sprite for display).
The
count_crtcs and
crtcs fields list the available CRTCs in the
configuration. A CRTC is simply an object that can scan out a framebuffer to a
display sink, and contains mode timing and relative position information.
CRTCs drive encoders, which are responsible for converting the pixel stream
into a specific display protocol (e.g. MIPI or HDMI).
The
count_connectors and
connectors fields list the available
physical connectors on the system. Note that some of these may not be exposed
from the chassis (e.g. LVDS or eDP). Connectors are attached to encoders and
contain information about the attached display sink (e.g. width and height in
mm, subpixel ordering, and various other properties).
The
count_encoders and
encoders fields list the available encoders
on the device. Each encoder may be associated with a CRTC, and may be used to
drive a particular encoder.
The min and max height fields indicate the maximum size of a framebuffer for
this device (i.e. the scanout size limit).
RETURN VALUE¶
Returns a drmModeRes structure pointer on success, 0 on failure.
REPORTING BUGS¶
Bugs in this function should be reported to
http://bugs.freedesktop.org under
the "Mesa" product, with "Other" or "libdrm" as
the component.
SEE ALSO¶
drmModeGetFB(3), drmModeAddFB(3), drmModeAddFB2(3), drmModeRmFB(3),
drmModeDirtyFB(3), drmModeGetCrtc(3), drmModeSetCrtc(3), drmModeGetEncoder(3),
drmModeGetConnector(3)