On Tue, 8 Nov 2016, Kai-Heng Feng wrote: > Hi, > > On Mon, Nov 7, 2016 at 7:02 PM, Oliver Neukum <oneukum@xxxxxxxx> wrote: > > On Fri, 2016-11-04 at 17:57 +0800, Kai-Heng Feng wrote: > >> Sometimes cdc_mbim failed to probe if runtime pm is enabled: > >> [ 9.305626] cdc_mbim: probe of 2-2:1.12 failed with error -22 > >> > >> This can be solved by increase its pm usage counter. > >> > >> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> > > > > For the record: > > > > NAK. This fixes a symptom. If this patch helps something is broken in > > device core. We need to find that. > > > > Please check attached dmesg with usbcore.dyndbg="+p". The log shows that the device went into suspend _before_ the cdc_mbim driver was probed, not during the probe. Then just before the probe was started, the USB core tried to resume the device and the resume failed. The log shows a bunch of other problems with this device: [ 3.862253] usb 2-2: config 1 has an invalid interface number: 12 but max is 1 [ 3.862254] usb 2-2: config 1 has an invalid interface number: 13 but max is 1 [ 3.862254] usb 2-2: config 1 has an invalid interface number: 13 but max is 1 [ 3.862255] usb 2-2: config 1 has no interface number 0 [ 3.862256] usb 2-2: config 1 has no interface number 1 ... [ 8.295180] usb 2-2: Disable of device-initiated U1 failed. [ 8.295322] usb 2-2: Disable of device-initiated U2 failed. I get the impression that the device won't work properly with runtime PM at all. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
