------- Original Message ------- On Tuesday, January 3rd, 2023 at 2:26 PM, Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> wrote: > On Wed, 28 Dec 2022 14:05:24 +0000 > Wahaj wahajaved@xxxxxxxxxxxxxx wrote: > >> Hi Jonathan >> >> Hope you're doing well. I have been using a laptop that comes with a >> CM32181 Light Sensor and after upgrading to the Linux kernel 6.0+, my >> laptop cannot seem to suspend because of the PM subsystem error. I >> have narrowed the problem down to this module and I believe that the >> commit 68c1b3dd5c48b2323067f8c1f0649ae2f31ab20bis the culprit >> >> The following lines were provided from the journalctl logs: >> >> >>> cm32181 i2c-CPLM3218:00: PM: dpm_run_callback(): >>> acpi_subsys_suspend+0x0/0x60 returns -121 cm32181 i2c-CPLM3218:00: >>> PM: failed to suspend async: error -121 >> >> I would love the chance to be able to work on this given any guidance >> on where to start > > > Hi Wahaj, > > Certainly seems likely that you have identified the right commit. > As a starting point, resend this email to linux-iio@xxxxxxxxxxxxxxx > and Kai-Heng Feng kai.heng.feng@xxxxxxxxxxxxx > > > If you could try reverting the commit to be completely sure it is > the cause that would help avoid any doubt. > Superficially the only thing that I can see causing this problem is > a fail of the i2c bus write. > > Does the device work prior to suspend? Try cat /sys/bus/iio/iio:device0/* > and see if you get any errors (may be device1 etc) > > If the device wasn't working at all the register writes in probe() should > have failed so we shouldn't be trying to suspend it. > It's possible your machine has some unusual power dependencies or > similar that mean the device is getting powered down before we try to > suspend it. > > Anyhow, better to have this discussion on list as there are many other people > who may have more insight than me or be able to replicate and help debug. > > Jonathan > >> Best Regards, >> Wahaj Javed Hi Jonathan and Kai-Heng Feng, I am currently using the 5.15 linux kernel for a while now which works perfectly fine. >From what I gather the suspend functionality does work when using an older Linux version without the PM i2c bus writes. The device does work fine prior to and post attempted suspend with no errors showing in cat /sys/bus/iio/iio:device0/* Let me know if there's anything I should start looking into Best Regards Wahaj Javed
