SUMMARY Changing the backlight brightness using PowerDevil doesn't allow it to go to it absolute potential. Upon setting the brightness to 100%, we can see that in `/sys/class/backlight/amdgpu_bl1/brightness` reads 100, however in `max_brighntess` we get 255 and writing that into the brightness file yields a way brighter output. STEPS TO REPRODUCE 1. Set the brightness to 100% using PowerDevil OBSERVED RESULT Display's brightness set to only 100/255. EXPECTED RESULT Display's brightness to be set to 255. (`/sys/class/backlight/amdgpu_bl1/max_brightness`) SOFTWARE/OS VERSIONS Operating System: Arch Linux KDE Plasma Version: 6.2.1 KDE Frameworks Version: 6.7.0 Qt Version: 6.8.0 Kernel Version: 6.9.10-arch1-1 (64-bit) Graphics Platform: X11 Processors: 16 × AMD Ryzen 7 6800HS with Radeon Graphics Memory: 14.9 GiB of RAM Graphics Processor: AMD Radeon 680M ADDITIONAL INFORMATION Additional files in the `/sys/class/backlight/amdgpu_bl1` sysfs (while KDE thinks the backlight is at "100%"): ``` /sys/class/backlight/amdgpu_bl1/actual_brightness : 100 /sys/class/backlight/amdgpu_bl1/bl_power : 0 /sys/class/backlight/amdgpu_bl1/brightness : 100 /sys/class/backlight/amdgpu_bl1/type : raw /sys/class/backlight/amdgpu_bl1/scale : unknown /sys/class/backlight/amdgpu_bl1/max_brightness : 255 ```
I believe I am having the same issue. I have a triple monitor setup (not a laptop), two via DisplayPort, one via HDMI. One monitor (the primary monitor - which is connected via DisplayPort), has this exact issue wherein the brightness after wake is limited by powerdevil to 30% on the monitor but powerdevil reports it set to 100%. I can override this with the monitor's hardware controls and increase it to 100% on the monitor, but if I touch powerdevil controls or restart it, it pushes it back down to 30% on the monitor. This issue didn't seem to happen before last week, but it may be just now apparent since the update to the powerdevil widget which now reliably persists throughout my session. Here is the output of `kscreen-doctor-o`: ``` Output: 1 DP-1 enabled connected priority 2 DisplayPort Modes: 1:2560x1440@60! 2:2560x1440@75* 3:1920x1200@60 4:1920x1080@120 5:1920x1080@120 6:1920x1080@120 7:1920x1080@100 8:1920x1080@60 9:1920x1080@60 10:1920x1080@60 11:1920x1080@50 12:1600x1200@60 13:1280x1440@60 14:1680x1050@60 15:1280x1024@75 16:1280x1024@60 17:1440x900@60 18:1280x800@60 19:1280x720@60 20:1280x720@60 21:1280x720@50 22:1024x768@120 23:1024x768@100 24:1024x768@75 25:1024x768@70 26:1024x768@60 27:832x624@75 28:800x600@120 29:800x600@100 30:800x600@75 31:800x600@72 32:800x600@60 33:800x600@56 34:720x576@50 35:720x576@50 36:720x480@60 37:720x480@60 38:720x480@60 39:720x480@60 40:640x480@120 41:640x480@100 42:640x480@75 43:640x480@73 44:640x480@67 45:640x480@60 46:640x480@60 47:640x480@60 48:720x400@70 49:1600x1200@60 50:1280x1024@60 51:1024x768@60 52:1920x1200@60 53:1280x800@60 54:2560x1440@60 55:1920x1080@60 56:1600x900@60 57:1368x768@60 58:1280x720@60 Geometry: 0,0 2560x1440 Scale: 1 Rotation: 1 Overscan: 0 Vrr: Never RgbRange: unknown HDR: incapable Wide Color Gamut: incapable ICC profile: none Color profile source: sRGB Color power preference: prefer efficiency and performance Brightness control: unsupported Output: 2 DP-2 enabled connected priority 1 DisplayPort Modes: 59:2560x1440@60! 60:2560x1440@144* 61:2560x1440@120 62:2560x1440@100 63:1920x1200@60 64:1920x1080@120 65:1920x1080@120 66:1920x1080@60 67:1920x1080@60 68:1920x1080@60 69:1920x1080@50 70:1600x1200@60 71:1280x1440@60 72:1680x1050@60 73:1280x1024@75 74:1280x1024@60 75:1440x900@60 76:1280x800@60 77:1280x720@60 78:1280x720@60 79:1280x720@50 80:1024x768@120 81:1024x768@100 82:1024x768@75 83:1024x768@70 84:1024x768@60 85:832x624@75 86:800x600@120 87:800x600@100 88:800x600@75 89:800x600@72 90:800x600@60 91:800x600@56 92:720x576@50 93:720x576@50 94:720x480@60 95:720x480@60 96:720x480@60 97:720x480@60 98:640x480@120 99:640x480@100 100:640x480@75 101:640x480@73 102:640x480@67 103:640x480@60 104:640x480@60 105:640x480@60 106:720x400@70 107:1600x1200@60 108:1280x1024@60 109:1024x768@60 110:1920x1200@60 111:1280x800@60 112:2560x1440@60 113:1920x1080@60 114:1600x900@60 115:1368x768@60 116:1280x720@60 Geometry: 2560,0 2560x1440 Scale: 1 Rotation: 1 Overscan: 0 Vrr: Never RgbRange: unknown HDR: incapable Wide Color Gamut: incapable ICC profile: none Color profile source: sRGB Color power preference: prefer efficiency and performance Brightness control: supported, set to 100% and dimming to 100% Output: 3 HDMI-A-1 enabled connected priority 3 HDMI Modes: 117:2560x1440@60! 118:2560x1440@75* 119:1920x1200@60 120:1920x1080@120 121:1920x1080@120 122:1920x1080@120 123:1920x1080@100 124:1920x1080@60 125:1920x1080@60 126:1920x1080@60 127:1920x1080@50 128:1600x1200@60 129:1280x1440@60 130:1680x1050@60 131:1280x1024@75 132:1280x1024@60 133:1440x900@60 134:1280x800@60 135:1280x720@60 136:1280x720@60 137:1280x720@50 138:1024x768@120 139:1024x768@100 140:1024x768@75 141:1024x768@70 142:1024x768@60 143:832x624@75 144:800x600@120 145:800x600@100 146:800x600@75 147:800x600@72 148:800x600@60 149:800x600@56 150:720x576@50 151:720x576@50 152:720x480@60 153:720x480@60 154:720x480@60 155:720x480@60 156:640x480@120 157:640x480@100 158:640x480@75 159:640x480@73 160:640x480@67 161:640x480@60 162:640x480@60 163:640x480@60 164:720x400@70 165:1600x1200@60 166:1280x1024@60 167:1024x768@60 168:1920x1200@60 169:1280x800@60 170:2560x1440@60 171:1920x1080@60 172:1600x900@60 173:1368x768@60 174:1280x720@60 Geometry: 5120,0 2560x1440 Scale: 1 Rotation: 1 Overscan: 0 Vrr: Never RgbRange: unknown HDR: incapable Wide Color Gamut: incapable ICC profile: none Color profile source: sRGB Color power preference: prefer efficiency and performance Brightness control: unsupported ```