Daniele Palmas <dnlplm@xxxxxxxxx> writes: > as a side note in latest kernels I had troubles with qmi devices > (e.g. I/O error when using qmicli). > > I found your suggestion in libqmi mailing list to revert commit > > 833415a3e781a26fe480a34d45086bdb4fe1e4c0 > cdc-wdm: fix "out-of-sync" due to missing notifications I guess a revert of that commit should be done then.. I have been stalling because I have been hoping to replace it with a better fix instead of a plain revert. I believe there are several issues playing badly together here. That commit was _expected_ to cause spurious EPIPE errors, which would be translated to EIO if they were propagated. But they should be filtered out rightaway, in theory. This works for me. I can see the EPIPEs with debugging, but I have never seen any EIO from read. And there is the problem: I am unable to reproduce this problem. I have previously tested this back and forth with several MDM9200 and MDM9235 generation modems in QMI mode, as well as in MBIM mode. And also with a number of other MBIM modems. Aleksander reported that he could reproduce the issue using an MDM9x15 generation modem in QMI mode, but not with any MDM9x00 or MDM9x35 modem. So I have now tried any way I can imagine to reproduce the issue with a Sierra Wireless EM7305, which is the only MDM9x15 modem I have. The firmware is SWI9X15C_05.05.58.00. But unfortunately the testing is still without "success". It plain works for me, every time, using ModemManager, qmicli with or without proxy, or uqmi. Would you mind describing in detail how you trigger the EIOs? What software and command sequence are you using? Does it reliably reproduce the issue, or do you have to try several times? What modem chipset and firmware is used? Bjørn -- 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
