1. "udevadm monitor -s drm" --> ``` monitor will print the received events for: UDEV - the event which udev sends out after rule processing KERNEL - the kernel uevent ```
2. "cat /sys/class/drm/card0-*/status" --> ``` disconnected connected disconnected ```
3. "cat /sys/kernel/debug/dri/0/i915_display_info" --> ``` CRTC info --------- [CRTC:91:pipe A]: uapi: enable=no, active=no, mode="": 0 0 0 0 0 0 0 0 0 0 0x0 0x0 [PLANE:31:plane 1A]: type=PRI uapi: fb=0,n/a,0x0, src=1920.000000x1080.000000+0.000000+682.000000, dst=1920x1080+0+0, rotation=0 (0x00000001) [PLANE:39:plane 2A]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:47:plane 3A]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:55:plane 4A]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:63:plane 5A]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:71:plane 6A]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:79:plane 7A]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:87:cursor A]: type=CUR uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) underrun reporting: cpu=yes pch=yes [CRTC:152:pipe B]: uapi: enable=yes, active=yes, mode="": 0 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x0 0x9 hw: active=yes, adjusted_mode="1920x1080": 60 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x48 0x9 pipe src size=1920x1080, dither=yes, bpp=18 num_scalers=2, scaler_users=0 scaler_id=-1, scalers[0]: use=no, mode=0, scalers[1]: use=no, mode=0 [ENCODER:275:DDI A]: connectors: [CONNECTOR:276:eDP-1] [PLANE:92:plane 1B]: type=PRI uapi: fb=277,XR24 little-endian (0x34325258),1920x1080, src=1920.000000x1080.000000+0.000000+0.000000, dst=1920x1080+0+0, rotation=0 (0x00000001) hw: fb=277,XR24 little-endian (0x34325258),1920x1080, visible=yes, src=1920.000000x1080.000000+0.000000+0.000000, dst=1920x1080+0+0, rotation=0 (0x00000001) [PLANE:100:plane 2B]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:108:plane 3B]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:116:plane 4B]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:124:plane 5B]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:132:plane 6B]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:140:plane 7B]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:148:cursor B]: type=CUR uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) underrun reporting: cpu=yes pch=yes [CRTC:213:pipe C]: uapi: enable=no, active=no, mode="": 0 0 0 0 0 0 0 0 0 0 0x0 0x0 [PLANE:153:plane 1C]: type=PRI uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:161:plane 2C]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:169:plane 3C]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:177:plane 4C]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:185:plane 5C]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:193:plane 6C]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:201:plane 7C]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:209:cursor C]: type=CUR uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) underrun reporting: cpu=yes pch=yes [CRTC:274:pipe D]: uapi: enable=no, active=no, mode="": 0 0 0 0 0 0 0 0 0 0 0x0 0x0 [PLANE:214:plane 1D]: type=PRI uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:222:plane 2D]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:230:plane 3D]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:238:plane 4D]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:246:plane 5D]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:254:plane 6D]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:262:plane 7D]: type=OVL uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) [PLANE:270:cursor D]: type=CUR uapi: fb=0,n/a,0x0, src=0.000000x0.000000+0.000000+0.000000, dst=0x0+0+0, rotation=0 (0x00000001) underrun reporting: cpu=yes pch=yes
Connector info -------------- [CONNECTOR:276:eDP-1]: status: connected physical dimensions: 310x170mm subpixel order: Unknown CEA rev: 0 DPCD rev: 11 audio support: no fixed mode: "1920x1080": 60 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x48 0x9 DP branch device present: no modes: "1920x1080": 60 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x48 0x9 "1920x1080": 48 113100 1920 1968 2000 2142 1080 1083 1089 1100 0x40 0x9 [CONNECTOR:284:HDMI-A-1]: status: disconnected [CONNECTOR:293:DP-1]: status: disconnected ```
1. "udevadm monitor -s drm" -->
```
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent
```
2. "cat /sys/class/ drm/card0- */status" -->
```
disconnected
connected
disconnected
```
3. "cat /sys/kernel/ debug/dri/ 0/i915_ display_ info" --> 000000x1080. 000000+ 0.000000+ 682.000000, dst=1920x1080+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) mode="1920x1080 ": 60 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x48 0x9 276:eDP- 1] ,1920x1080, src=1920. 000000x1080. 000000+ 0.000000+ 0.000000, dst=1920x1080+0+0, rotation=0 (0x00000001) ,1920x1080, visible=yes, src=1920. 000000x1080. 000000+ 0.000000+ 0.000000, dst=1920x1080+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001) 000000+ 0.000000+ 0.000000, dst=0x0+0+0, rotation=0 (0x00000001)
```
CRTC info
---------
[CRTC:91:pipe A]:
uapi: enable=no, active=no, mode="": 0 0 0 0 0 0 0 0 0 0 0x0 0x0
[PLANE:31:plane 1A]: type=PRI
uapi: fb=0,n/a,0x0, src=1920.
[PLANE:39:plane 2A]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:47:plane 3A]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:55:plane 4A]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:63:plane 5A]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:71:plane 6A]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:79:plane 7A]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:87:cursor A]: type=CUR
uapi: fb=0,n/a,0x0, src=0.000000x0.
underrun reporting: cpu=yes pch=yes
[CRTC:152:pipe B]:
uapi: enable=yes, active=yes, mode="": 0 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x0 0x9
hw: active=yes, adjusted_
pipe src size=1920x1080, dither=yes, bpp=18
num_scalers=2, scaler_users=0 scaler_id=-1, scalers[0]: use=no, mode=0, scalers[1]: use=no, mode=0
[ENCODER:275:DDI A]: connectors:
[CONNECTOR:
[PLANE:92:plane 1B]: type=PRI
uapi: fb=277,XR24 little-endian (0x34325258)
hw: fb=277,XR24 little-endian (0x34325258)
[PLANE:100:plane 2B]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:108:plane 3B]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:116:plane 4B]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:124:plane 5B]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:132:plane 6B]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:140:plane 7B]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:148:cursor B]: type=CUR
uapi: fb=0,n/a,0x0, src=0.000000x0.
underrun reporting: cpu=yes pch=yes
[CRTC:213:pipe C]:
uapi: enable=no, active=no, mode="": 0 0 0 0 0 0 0 0 0 0 0x0 0x0
[PLANE:153:plane 1C]: type=PRI
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:161:plane 2C]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:169:plane 3C]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:177:plane 4C]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:185:plane 5C]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:193:plane 6C]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:201:plane 7C]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:209:cursor C]: type=CUR
uapi: fb=0,n/a,0x0, src=0.000000x0.
underrun reporting: cpu=yes pch=yes
[CRTC:274:pipe D]:
uapi: enable=no, active=no, mode="": 0 0 0 0 0 0 0 0 0 0 0x0 0x0
[PLANE:214:plane 1D]: type=PRI
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:222:plane 2D]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:230:plane 3D]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:238:plane 4D]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:246:plane 5D]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:254:plane 6D]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:262:plane 7D]: type=OVL
uapi: fb=0,n/a,0x0, src=0.000000x0.
[PLANE:270:cursor D]: type=CUR
uapi: fb=0,n/a,0x0, src=0.000000x0.
underrun reporting: cpu=yes pch=yes
Connector info 276:eDP- 1]: status: connected 284:HDMI- A-1]: status: disconnected 293:DP- 1]: status: disconnected
--------------
[CONNECTOR:
physical dimensions: 310x170mm
subpixel order: Unknown
CEA rev: 0
DPCD rev: 11
audio support: no
fixed mode: "1920x1080": 60 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x48 0x9
DP branch device present: no
modes:
"1920x1080": 60 141380 1920 1968 2000 2142 1080 1083 1089 1100 0x48 0x9
"1920x1080": 48 113100 1920 1968 2000 2142 1080 1083 1089 1100 0x40 0x9
[CONNECTOR:
[CONNECTOR:
```