Hi Alan, On Wed, 4 Jan 2023 11:18:29 -0500 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, Jan 04, 2023 at 04:49:00PM +0100, Petr Tesařík wrote: > > On Wed, 4 Jan 2023 15:13:41 +0100 > > Petr Tesařík <petr@xxxxxxxxxxx> wrote: > > > > > Hi folks, > > > > > > I'm struggling with autosuspend on my Samsung phone in download mode, > > Wait... Autosuspend is carried out by the host, but you appear to be > stating that the Samsung phone is acting as a USB device (i.e., it's > being autosuspended, not that it is autosuspending something else). > Is that right? You're right. There's a typo in this sentence. It's not autosuspend _ON_ my Samsung phone, but autosuspend _OF_ my Samsung phone. So, yes, the phone is in gadget mode, and I'm seeing all these ïssues on the host (a ThinkPad E595, but that's most likely irrelevant). Petr T > > > as it apparently breaks heimdall/libusb on my Tumbleweed system. Here's > > > what I'm seeing: > > > > > > - My device is autosuspended, because it has been idle for long enough. > > > - cd /sys/bus/usb/devices/1-4/ # my device's port > > > - echo -1 > power/autosuspend > > > - The device is reset and gets a new device ID. > > > The current directory is no longer valid (becomes empty). > > > > On a second thought, this looks like the actual bug. I don't think > > we're supposed to see a disconnect+reconnect whenever a suspended USB > > device is resumed. Then again, I'm no expert on USB... > > In general there should not be a disconnect during a resume. But it can > happen, depending on how the device behaves. Perhaps your phone is > disconnecting deliberately. > > The dmesg log ought to contain some useful information, particularly if > you enable USB kernel debugging before starting the experiment: > > echo 'module usbcore =p' >/sys/kernel/debug/dynamic_debug/control > > Alan Stern
