Re: USB-C adapter like Dell DA300 using > 5 W

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Aug 21, 2024 at 11:32:04PM +0200, Paul Menzel wrote:
> Dear Linux folks,
> 
> 
> On the Intel Kaby Lake laptop Dell XPS 13 9360 with Debian sid/unstable and
> *powertop* 2.15-3, connecting a USB-C adapter like Dell DA300 or LMP USB-C
> mini Dock (P/N 15954) [1] and connecting only an Ethernet cable (module
> r8152 is used), the adapter gets very hot, and according to PowerTOP it uses
> over 5 Watts – almost more as the laptop idling.
> 
>     $ lsusb
>     Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
>     Bus 001 Device 002: ID 0cf3:e300 Qualcomm Atheros Communications QCA61x4
> Bluetooth 4.0
>     Bus 001 Device 003: ID 04f3:2234 Elan Microelectronics Corp. Touchscreen
>     Bus 001 Device 004: ID 0c45:670c Microdia Integrated Webcam HD
>     Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
>     Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
>     Bus 003 Device 002: ID 2109:2820 VIA Labs, Inc. VL820 Hub
>     Bus 003 Device 003: ID 06c4:c412 Bizlink International Corp. DELL DA300
>     Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
>     Bus 004 Device 002: ID 2109:0820 VIA Labs, Inc. VL820 Hub
>     Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153
> Gigabit Ethernet Adapter
> 
> With `LANG= sudo powertop --auto-tune` it stays high.
> 
> PowerTOP:
> 
> ```
> The battery reports a discharge rate of 6.01 W
> The energy consumed was 146 J
> The estimated remaining time is 3 hours, 51 minutes
> 
> Summary: 384.6 wakeups/second,  0.0 GPU ops/seconds, 0.0 VFS ops/sec and
> 8.5% CPU use
> 
> Power est.              Usage       Events/s    Category       Description
>   5.94 W      0.0%                      Device         Display backlight
>   5.23 W    100.0%                      Device         USB device: USB
> Optical Mouse (Logitech)
>   4.62 W     66.1%                      Device         USB device: USB
> 10/100/1000 LAN (Realtek)
>   205 mW    100.0%                      Device         USB device: Fujitsu
> Keyboard (Fujitsu)
>  14.1 mW     13.5 ms/s       0.9        kWork intel_atomic_commit_work
> ```
> 
> At another time:
> 
> ```
> The battery reports a discharge rate of 10.5 W
> The energy consumed was 235 J
> The estimated remaining time is 2 hours, 20 minutes
> 
> Summary: 395.8 wakeups/second,  0.0 GPU ops/seconds, 0.0 VFS ops/sec and
> 23.8% CPU use
> 
> Power est.              Usage       Events/s    Category       Description
>   7.13 W    100.0%                      Device         USB device: USB
> 10/100/1000 LAN (Realtek)
>   3.92 W     15.8%                      Device         Display backlight
>   320 mW      0.0 us/s      0.00        Process        [PID 1349]
> /usr/bin/pipewire
>  63.6 mW     65.4 ms/s       0.5        Process        [PID 4982]
> /usr/lib/thunderbird/thunderbird
>  24.9 mW     25.6 ms/s       6.7        Process        [PID 37753]
> /usr/lib/firefox-nightly/firefox-bin -contentproc -isForBrowser -prefsLen
> 36793 -prefMapSize 265654 -jsInitLe
>  14.7 mW     15.1 ms/s       0.5        kWork intel_atomic_commit_work
> ```
> 
> The heat of the USB-C adapter might suggest, that it draws that much power.
> What is your experience? Can you suggest something?

Buy a different adapter?  That seems like something is really wrong with
it.  Does other devices also suck that much power from that port on the
laptop?

thanks,

greg k-h