Re: [PATCH] ACPI / LPSS: Don't skip late system PM ops for hibernate on BYT/CHT

From: Robert R. Howell
Date: Thu Apr 25 2019 - 12:38:40 EST

On 4/24/19 1:20 AM, Rafael J. Wysocki wrote:

> On Tue, Apr 23, 2019 at 10:03 PM Robert R. Howell <RHowell@xxxxxxxx> wrote:
>> On 4/23/19 2:07 AM, Rafael J. Wysocki wrote:
>>> On Sat, Apr 20, 2019 at 12:44 AM Robert R. Howell <RHowell@xxxxxxxx> wrote:
>>>> On 4/18/19 5:42 AM, Hans de Goede wrote:
>>>>>> On 4/8/19 2:16 AM, Hans de Goede wrote:>
>>>>>>> Hmm, interesting so you have hibernation working on a T100TA
>>>>>>> (with 5.0 + 02e45646d53b reverted), right ?
>>>> I've managed to find a way around the i2c_designware timeout issues
>>>> on the T100TA's. The key is to NOT set DPM_FLAG_SMART_SUSPEND,
>>>> which was added in the 02e45646d53b commit.
>>>> To test that I've started with a 5.1-rc5 kernel, applied your recent patch
>>>> to acpi_lpss.c, then apply the following patch of mine, removing
>>>> DPM_FLAG_SMART_SUSPEND. (For the T100 hardware I need to apply some
>>>> other patches as well but those are not related to the i2c-designware or
>>>> acpi issues addressed here.)
>>>> On a resume from hibernation I still see one error:
>>>> "i2c_designware 80860F41:00: Error i2c_dw_xfer called while suspended"
>>>> but I no longer get the i2c_designware timeouts, and audio does now work
>>>> after the resume.
>>>> Removing DPM_FLAG_SMART_SUSPEND may not be what you want for other
>>>> hardware, but perhaps this will give you a clue as to what is going
>>>> wrong with hibernate/resume on the T100TA's.
>>> What if you drop DPM_FLAG_LEAVE_SUSPENDED alone instead?
>> I did try dropping just DPM_FLAG_LEAVE_SUSPENDED, dropping just
>> DPM_FLAG_SMART_SUSPEND, and dropping both flags. When I just drop
>> DPM_FLAG_LEAVE_SUSPENDED I still get the i2c_designware timeouts
>> after the resume. If I drop just DPM_FLAG_SMART_SUSPEND or drop both,
>> then the timeouts go away.
> OK, thanks!
> Is non-hibernation system suspend affected too?

I just ran some tests on a T100TA, using the 5.1-rc5 code with Hans' patch applied
but without any changes to i2c-designware-platdrv.c, so the
are all set.

Suspend does work OK, and after resume I do NOT get any of the crippling
i2c_designware timeout errors which cause sound to fail after hibernate. I DO see one
"i2c_designware 80860F41:00: Error i2c_dw_xfer call while suspended"
error on resume, just as I do on hibernate. I've attached a portion of dmesg below.
The "asus_wmi: Unknown key 79 pressed" error is a glitch which occurs
intermittently on these machines, but doesn't seem related to the other issues.
I had one test run when it was absent but the rest of the messages were the
same -- but then kept getting that unknown key error on all my later tries.

I did notice the "2sidle" in the following rather than "shallow" or "deep". A
cat of /sys/power/state shows "freeze mem disk" but a
cat of /sys/power/mem_sleep" shows only "[s2idle] so it looks like shallow and deep
are not enabled for this system. I did check the input power (or really current)
as it went into suspend and the micro-usb power input drops from about
0.5 amps to 0.05 amps. But clearly a lot of devices are still active, as movement
of a bluetooth mouse (the MX Anywhere 2) will wake it from suspend. That presumably is
why suspend doesn't trigger the same i2c_designware problems as hibernate.

Let me know if I can do any other tests.

Bob Howell

----DMESG OUTPUT ON SUSPEND------------------
[ 71.791495] NET: Registered protocol family 38
[ 73.150736] input: MX Anywhere 2 Keyboard as /devices/virtual/misc/uhid/0005:046D:B013.0005/input/input24
[ 73.156612] input: MX Anywhere 2 Mouse as /devices/virtual/misc/uhid/0005:046D:B013.0005/input/input25
[ 73.159504] hid-generic 0005:046D:B013.0005: input,hidraw4: BLUETOOTH HID v0.07 Keyboard [MX Anywhere 2] on 74:D0:2B:DF:77:E9
[ 102.719170] asus_wmi: Unknown key 79 pressed
[ 102.897214] asus_wmi: Unknown key 79 pressed
[ 104.298409] PM: suspend entry (s2idle)
[ 104.298414] PM: Syncing filesystems ... done.
[ 105.410883] Freezing user space processes ... (elapsed 0.002 seconds) done.
[ 105.413556] OOM killer disabled.
[ 105.413558] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 123.353720] i2c_designware 80860F41:00: Error i2c_dw_xfer call while suspended
[ 123.635028] ACPI: button: The lid device is not compliant to SW_LID.
[ 124.086421] OOM killer enabled.
[ 124.086491] Restarting tasks ... done.
[ 124.120647] PM: suspend exit
[ 124.939566] asus_wmi: Unknown key 79 pressed