<gordan>
Having a really odd problem with mainline kernels.
<gordan>
Power monitoring.
<gordan>
Battery specifically.
<gordan>
It updates when the machine reboots.
<gordan>
But then ceases updating.
<gordan>
So you don't know how much battery there is left unless you reboot.
<Wizzup>
what device?
<Wizzup>
with 4.2 I have no such problem
<Wizzup>
on peach pi and snow
<javier__>
gordan: mm, that used to work as well. If doesn't work for you with 4.3 then is another regression...
<gordan>
I am on 4.3
<gordan>
It updates on a reboot.
<gordan>
But the upower says last updated X seconds ago which is besically the same as uptime.
<gordan>
Where is it read from?
<gordan>
Is there anything that can be poked to make it refresh?
<javier__>
gordan: afaik from /sys/class/power_supply/*
* gordan
looks
<javier__>
then you have the battery and AC
<javier__>
*there
<Wizzup>
find sys | grep time_util_full or so
<javier__>
gordan: I've a v4.3-rc6 in my peach pi now and /sys/class/power_supply/sbs-20-000b/capacity is updated
<javier__>
gordan: can you check that upower is running correnctly? maybe the problem is in user-space?
<gordan>
Yeah, just looking. It looks like a userspace issue of some sort.
<gordan>
I see the charge_now changing, and time_to_{empty,full} also changing...
steev_ has quit [Read error: Connection reset by peer]
gordan_ has joined #linux-exynos
gordan has quit [Ping timeout: 260 seconds]
masta has quit [Read error: Connection reset by peer]
masta has joined #linux-exynos
afaerber_ has quit [Quit: Ex-Chat]
afaerber has joined #linux-exynos
EmilMedve has quit [Quit: Leaving.]
armnold has joined #linux-exynos
armnold has quit [Client Quit]
liquidAcid has joined #linux-exynos
<gordan_>
Weird. The power monitoring issue seems to be to do with upowerd.
<gordan_>
If I do systemctl restart upowerd, it refreshes the stats visible to upower -d
gordan_ is now known as gordan
<javier__>
gordan: so upowerd does not crash but just gets borked?
<javier__>
anything in the logs?
<gordan>
Pretty much yes.
<gordan>
upowerd seems to take no meaningful options, it's just the dbus endpoint listening for requests.
<gordan>
I'm not sure what it it supposed to do underneath.
<gordan>
upower -d does show the relevant /sys paths that I can go investigate, but those do seem to contain data that does change with the batter charge state.
<gordan>
Where would upowerd logs be normally?
<javier__>
gordan: I've no idea tbh
<javier__>
gordan: you can run with strace and see what files opens
<gordan>
The only thing that contains anything related seems to be syslog
<gordan>
And the only message upowerd emits is that it cannot open /sys/class/leds
<gordan>
Because it doesn't exist.
<gordan>
Also, powerdevil seems to not be able to set the backlight brightness for some reason.
<gordan>
Hmm, also, upowerd is complaining it cannot open /proc/timer_stats.
<gordan>
Which also doesn't exist.
<gordan>
Is there a kernel option I need to enable to make /proc/timer_stats appear? Could this be why it's not refreshing properly?
<javier__>
gordan: a quick grep shows me that the option you are are looking for is CONFIG_TIMER_STATS
<javier__>
but I don't think that is a requirement for upowerd
<javier__>
most likely there is a bug in the version you are using
<gordan>
Joy.
<gordan>
FWIW the user-space bit seems to work on Snow with it's ChromiumOS 3.4 franken-kernel.
<javier__>
mmm
<Wizzup>
I use wmii and wrote a script to read the sys entry and print the time
<gordan>
But running the ChromiumOS franken-kernel isn't an option for me on Peach because it won't boot from mainline u-boot (I'm going to hazard a guess it's something to do with expectation/provision of simplefb, which appears to have long since been done away with in mainline, both u-boot and kernel.
<gordan>
Yeah, I know I can do that manually, but that's not quite the point here, I'd rather avoid Linux-from-scratch approaches here. ;)
<Wizzup>
batti also works well :)
<javier__>
gordan: I'm not familiar with upowerd sorry, so the only suggestion I can give you is to debug
<Wizzup>
although, nevermind
<gordan>
On a totally unrelated note, what driver is used for the built in webcam? I find power management on it is not enabled by default, powertop shows it burning at 100% even when it's not enabled, until I ask it to "do someting" (which it doesn't tell me what it is), at which point it goes down to 0%.
<gordan>
OK, thanks.
<javier__>
gordan: the webcam uses the UVC driver
<javier__>
gordan: is a normal USB camera that is hardwired
<gordan>
What is the driver config sumbol in .config for it?
<gordan>
I've been through the menuconfig 3 times and for the life of me I cannot find it.
<javier__>
gordan: the config symbol is CONFIG_USB_VIDEO_CLASS and the driver is drivers/media/usb/uvc/
<gordan>
Hmm... I get nothing for grepping .config for USB_VIDEO....
<gordan>
Device Drivers sub-meny has "Multimedia" option completely disabled.
<gordan>
Yet there it is in powertop...
<javier__>
gordan: right, it is not enabled for Exynos by default in v4.3 but will be in v4.4
<javier__>
commit in -next: fa4d0b79209e ARM: exynos_defconfig: Enable USB Video Class support
<gordan>
I see.
<gordan>
So without a driver for it loaded, it's defaulting to being active rather than inactive?
<gordan>
Surrely the default should be inactive for any devices without a driver loaded.
<javier__>
dunno, how powertop gets its statistics
<gordan>
I'm more interested in what it does, the interface got dumbed down recently. It used to state what it would do.
<gordan>
Lo and behold, addint the driver for the webcam to the kernel (I built it as a module) results in the device activity to indeed to down to 0% when it's not being used.
zombah_ has joined #linux-exynos
afaerber has quit [Quit: Ex-Chat]
gordan has left #linux-exynos ["Konversation terminated!"]