01-08-2021, 04:29 AM
(This post was last modified: 01-08-2021, 04:53 AM by dsimic.
Edit Reason: Also replied to the latest responses
)
Thank you for checking it further! I'm sorry that you effectively panicked your laptop in the process.
The remark on even numbers as the interrupt counts is a good one, but, for example, I currently have 33 as the interrupt count, which for some reason hasn't changed in the last few hours. I'll try to keep an eye on that. By the way, I don't use WiFi or Bluetooth, which consequently shouldn't be the root cause.
I've just finished checking the PineBook Pro schematic, the DTS file and the source code of related Linux kernel drivers, and you're right, the disabling and enabling of the internal speakers is performed by the drivers, which use the headphones detection to turn off and on the amplifiers that power the internal speakers.
Speaking of that, I do hear some faint popping/clicking noises coming randomly out of the internal speakers, which might be the result of the amplifiers being turned off and on, as a result of spurios headphones detection interrupts. I'll try to debug that further.
I doubt that any percussion maintenance
would actually help because the source of the headphones detection interrupt comes from the audio codec (which actually isn't documented exactly how), and the Linux kernel driver that handles the RK3399's associated GPIO line has also debouncing enabled on it.
Anyway, I tried tapping the laptop case lightly near the headphones jack, and no new interrupts were generated. I'll also try inserting and removing the headphones jack a few more times, as the cause might be related to a not-so-great auxiliary connection inside the headphones jack, which is used to signal the absence of the headphones to the audio codec.
Edit: I have also replied to the latest responses.
The remark on even numbers as the interrupt counts is a good one, but, for example, I currently have 33 as the interrupt count, which for some reason hasn't changed in the last few hours. I'll try to keep an eye on that. By the way, I don't use WiFi or Bluetooth, which consequently shouldn't be the root cause.
I've just finished checking the PineBook Pro schematic, the DTS file and the source code of related Linux kernel drivers, and you're right, the disabling and enabling of the internal speakers is performed by the drivers, which use the headphones detection to turn off and on the amplifiers that power the internal speakers.
Speaking of that, I do hear some faint popping/clicking noises coming randomly out of the internal speakers, which might be the result of the amplifiers being turned off and on, as a result of spurios headphones detection interrupts. I'll try to debug that further.
I doubt that any percussion maintenance
would actually help because the source of the headphones detection interrupt comes from the audio codec (which actually isn't documented exactly how), and the Linux kernel driver that handles the RK3399's associated GPIO line has also debouncing enabled on it.Anyway, I tried tapping the laptop case lightly near the headphones jack, and no new interrupts were generated. I'll also try inserting and removing the headphones jack a few more times, as the cause might be related to a not-so-great auxiliary connection inside the headphones jack, which is used to signal the absence of the headphones to the audio codec.
Edit: I have also replied to the latest responses.