[Letux-kernel] Letux 4.12-rc3 coming

H. Nikolaus Schaller hns at goldelico.com
Mon May 29 11:13:46 CEST 2017

I am just upgrading to 4.12-rc3. There have again been changes to serdev (and its integration into tty).
Bluetooth did kernel panic on GTA04A5 but worked on Pyra with just a lock dependency warning (both are using the same WL1837MOD).
Otherwise things seem to work better. The double-probe() problem of serdev+tty drivers has disappeared.

Next I am thinking about the Bluetooth support. I didn't know so far that there is sort of kernel-built-in-hciattach.
I.e. we just have to register the w2cbw as a hci device and there is no need for a user-space daemon any more.

Looks good - except one thing. We might need to be able to access the serial interface for baudrate probing.
Well, we don't... Because all GTA04 boards with working w2cbw have already been reconfigured to 3Mbit/s.
And it is very unlikely that one of the broken boards get repaired.

In that rare case it is still possible to boot without the serdev driver module (we will then have a /dev/ttyO0)
and turn on WLAN to power on the BT side.

Or I add a CONFIG option so that the w2cbw driver can either expose a /dev/ttyBT0 or a hci0 interface.


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