On Wed, 2019-02-20 at 19:28 +0200, Mathias Nyman wrote: > On 14.2.2019 20.04, Eric Blau wrote: > > On Thu, Feb 14, 2019 at 9:56 AM Mathias Nyman > > <mathias.nyman@xxxxxxxxxxxxxxx> wrote: > > > > Thanks for looking into this, Mathias. Now that you point this out, on > > > > older kernels where suspend and resume works, I noticed the following > > > > log messages emitted when resuming from suspend: > > > > > > > > Feb 06 18:58:05 eric-macbookpro kernel: usb usb2-port3: Cannot enable. > > > > Maybe the USB cable is bad? > > > > > > Attached a testpatch that should react to ports stuck in polling state, > > > and warm reset them. > > > > > > It doesn't limit the numbers of reset tries, or allow system suspend with ports > > > stuck in polling state, but I'd like to know how the MacBook reacts to it > > > > > > Can you test it with debugging enabled? > > > > Hi Mathias, > > > > Thanks for the patch. I tested it against 4.20.8 and got a couple > > successful suspends but on the third attempt I got the same failure > > again. I noticed after the first suspend/resume, the card reader > > showed as "Link:Compliance" but on later attempts it showed stuck in > > Polling again. > > > > I've attached the logs with debugging enabled. > > > > Thanks, logs show that several resets won't recover the card reader. > > I'm taking a different approach, USB3 ports in polling state should > automatically move to connected/enabled. So instead of preventing > suspend if a port is found in polling I'll let it try to finish link > training for some time, and then just continue with suspend if it fails. > > Patch attached. > > This won't fix the broken card reader, but should allow your MacBook to suspend. > After this we can start looking at fixing the card reader, Ivan Miranov sent some > proposal for this. > > -Mathias Hi Mathias, I applied your patch on top of v5.0-rc8 and tested it on my laptop. It fixes the suspend problem from the kernel side, but there is another one: starting with the second suspend, XHCI controller wakes up the system just after few seconds after suspending. Laptop keeps looping through suspend/resume while lid is closed. Such behaviour is quite stable: I was able to reproduce this three times with reboots in between. Corresponding dmesg and traces are here (from one run only): https://github.com/im-0/investigate-card-reader-suspend-problem-on-mbp11.4/tree/master/test-22 After disabling ACPI wake up on XHC1 (echo XHC1 >/proc/acpi/wakeup), everything works as expected: suspend/resume works fine multiple times, card reader remains missing after the first suspend/resume.
