1DRMMODEGETRESOURCES(3) Direct Rendering Manager DRMMODEGETRESOURCES(3)
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6 drmModeGetResources - retrieve current display configuration informa‐
7 tion
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10 #include <xf86drm.h>
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12 #include <xf86drmMode.h>
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14 drmModeResPtr drmModeGetResources(int fd);
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17 drmModeGetResources allocates, populates, and returns a drmModeRes
18 structure containing information about the current display configura‐
19 tion. The structure contains the following fields:
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21 typedef struct _drmModeRes {
22 int count_fbs;
23 uint32_t *fbs;
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25 int count_crtcs;
26 uint32_t *crtcs;
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28 int count_connectors;
29 uint32_t *connectors;
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31 int count_encoders;
32 uint32_t *encoders;
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34 uint32_t min_width, max_width;
35 uint32_t min_height, max_height;
36 } drmModeRes, *drmModeResPtr;
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38 The count_fbs and fbs fields indicate the number of currently allocated
39 framebuffer objects (i.e., objects that can be attached to a given CRTC
40 or sprite for display).
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42 The count_crtcs and crtcs fields list the available CRTCs in the con‐
43 figuration. A CRTC is simply an object that can scan out a framebuffer
44 to a display sink, and contains mode timing and relative position in‐
45 formation. CRTCs drive encoders, which are responsible for converting
46 the pixel stream into a specific display protocol (e.g., MIPI or HDMI).
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48 The count_connectors and connectors fields list the available physical
49 connectors on the system. Note that some of these may not be exposed
50 from the chassis (e.g., LVDS or eDP). Connectors are attached to en‐
51 coders and contain information about the attached display sink (e.g.,
52 width and height in mm, subpixel ordering, and various other proper‐
53 ties).
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55 The count_encoders and encoders fields list the available encoders on
56 the device. Each encoder may be associated with a CRTC, and may be used
57 to drive a particular encoder.
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59 The min_* and max_* fields indicate the maximum size of a framebuffer
60 for this device (i.e., the scanout size limit).
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63 drmModeGetResources returns a drmModeRes structure pointer on success,
64 NULL on failure. The returned structure must be freed with drmMode‐
65 FreeResources(3).
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68 Bugs in this function should be reported to
69 https://gitlab.freedesktop.org/mesa/drm/-/issues
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72 drm(7), drm-kms(7), drmModeGetFB(3), drmModeAddFB(3), drmModeAddFB2(3),
73 drmModeRmFB(3), drmModeDirtyFB(3), drmModeGetCrtc(3), drmModeSetCrtc
74 (3), drmModeGetEncoder (3), drmModeGetConnector(3)
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79 September 2012 DRMMODEGETRESOURCES(3)