On 7/20/05, Sergey Vlasov <[EMAIL PROTECTED]> wrote: > On Tue, 19 Jul 2005 23:40:18 -0400 Stephen Evanchik wrote: > > > I have been receiving a lot of complaints that TrackPoints on > > Synaptics pass-thru ports stopped working with 2.6.12. I retested > > 2.6.9 and 2.6.11-rc3 successfully, I believe 2.6.11.7 may also work > > but that is unconfirmed at this point. > > > > The behavior is always the same .. after sending the read secondary ID > > command, the TrackPoint seems to be disabled from that point forward. > > > > Any ideas? > > Looks like this problem was introduced by the change from PSMOUSE_PS2 to > PSMOUSE_TRACKPOINT in the TrackPoint support patch. The Synaptics > driver needs to know whether the device on the pass-thru port is using > 3-byte or 4-byte packets; however, instead of checking child->pktsize, > it checks child->type >= PSMOUSE_GENPS - and this check is now giving a > wrong result. Therefore the Synaptics driver configures the pass-thru > port for 4-byte packets, and all 3-byte packets from TrackPoint seem to > be thrown away.
Oh, yes, that would do it. > The patch below is reported to fix the problem - now the 4-byte mode is > used only if child->pktsize == 4. That is the correct fix. > Another option is to change the > PSMOUSE_TRACKPOINT value so that it is less than PSMOUSE_GENPS, No, protocol numbers should not be changed as userspace drivers/setups check them and rely on them being stable. That's why psmouse->pktsize was introduced to begin with. Unfortunately synaptics pass-through piece was missed and not adjusted. I will add the patch to my tree, thanks! > In theory, someone could attach a device which uses 6-byte packets to > the Synaptics pass-thru port; I'm not sure what would happen in this > case, but with Synaptics confugured for 3-byte packets (as the patch > below will do) this configuration even has a chance of working. I don't think it can support more than 4 byte packets. bytes 0 and 3 are protocol markers and can't be readily used for transmitting other protocols data. -- Dmitry - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
