Linux 6.7 To Add POWER-Z Driver For Exposing USB Power Measurements

[phoronix]

Phoronix: Linux 6.7 To Add POWER-Z Driver For Exposing USB Power Measurements

For those curious about the power consumption of USB-C devices, there are some nifty devices out there that have a LED display and can report the voltage, Amps, Wattage, and USB power delivery protocol version of connected devices. It's a neat display but with a new POWER-Z driver coming to the Linux kernel it's possible to propagate that information from the system itself with this new driver...

https://www.phoronix.com/news/Linux-POWER-Z-USB-Power-Driver

[Snaipersky]

The name really made me think it was an IBM project.

[dougg]

The KM002C and KM003C are the models supported. Power-Z is a brand name of products made for ChargerLab.com which I believe is Hong Kong based. Naming is hard! The interesting thing about these USB-C power monitors is EPR support (up to 48 Volts at 5 Amps for 240 Watts although ChargerLab claim they can measure up to 8 or 10 Amps (depending on the mode)l). Apart from having male and female USB-C connectors, these power monitors have a third USB-C receptacle for a HID interface which is what this new driver is accessing.

ChargerLab supply firmware updates for these monitors plus a Windows app. The sensors utility in Linux will show the real-time voltage/current/power info that is shown on the dongle (as shown in the picture associated with this article). The Windows app will additionally show the PD messages passing between the PD source and sink (and cable) which is _not_ available from this driver at the moment. That would be a very useful addition to this driver IMO.


[Michael [or forum moderator]: these adverts are just too much! As I type, this input window continually disappears off this laptop screen as another bloody advert pops up and re-formats this page. This makes it very hard to concentrate and add more useful info to a reply like this.]

[dougg]

Apart from chargerlab.com which is a very good site for USB-C PD equipment, I highly recommend the allthingsoneplace YouTube channel in which a faceless engineer puts USB-C PD equipment (mainly chargers) through their paces. He seems to be on a never ending search for the best PD power adapter on the market.

[edwaleni]

100% behind this effort. My Anker power brick gives me more information about its input and output status than any UPS under a $1000.

UPS vendors have gotten really lazy in reporting power telemetry to desktop users. They expect you to have hundreds of UPS'es nationally and use their proprietary client server solution.

[LtdJorge]

[Michael [or forum moderator]: these adverts are just too much! As I type, this input window continually disappears off this laptop screen as another bloody advert pops up and re-formats this page. This makes it very hard to concentrate and add more useful info to a reply like this.]

You can always buy a subscription to the site and have no ads

[dougg]

You can always buy a subscription to the site and have no ads

Thanks for reminding me as my yearly subscription is nearly up. Will renew now, at lwn.net .

[Forge]

You can always buy a subscription to the site and have no ads

I mean, there's a balance to be struck. Getting militant about subscriptions while not addressing major QOL issues just makes the free users either go ad-block or go away, and getting militant against ad-blocking converts almost every non-sub user to a non-user over time.

The original point is valid. If the ads loading are causing the page to reflow to the point where the text entry vanishes off screen, that's worth looking into.

Personally, I think dougg should be lauded for browsing without adblock, since that's painful. Moreso if adblock is disabled specifically for *.phoronix.com.