On 04.03.2015 08:42, Georg Chini wrote: > On 02.03.2015 23:02, Georg Chini wrote: >> On 02.03.2015 07:41, Georg Chini wrote: >>> On 23.02.2015 09:06, David Henningsson wrote: >>>> >>>> >>>> On 2015-02-21 23:14, Georg Chini wrote: >>>>> Hello, >>>>> >>>>> >>>>> >>>>> With the Plantronics 590, the connect() call in bluez5_sco_acquire_cb >>>>> returns >>>>> "Protocol not supported". The headset itself is functional, I tested >>>>> with my mobile. >>>>> >>>> I've heard of this, but never seen it myself. I suspect it's a >>>> kernel regression, but I'm not sure. Does it work with older >>>> kernels? Like, one, two, three years old kernels or such? >>>> >>> >> Yes, it is a kernel regression introduced in 3.12. There are two >> reasons why it does no longer >> work: >> 1) The driver expects the headset to issue a sync connection finished >> event (0x2c), even >> if the connection attempt fails, so that it can test various packet >> types until it succeeds. >> My old headset does not do so, it just sends a command status event >> (0x0f) with the >> status code 0x1a. So the driver tries its first option and then fails. >> 2) The headset apparently needs a retrans_effort of 0xff (whatever >> that parameter means) >> instead of 0x01. I just noticed that this has already been fixed in 3.18, sorry for the noise.
