james wrote: > On Thu, Jul 21, 2011 at 12:14:14AM -0400, Martin Langhoff wrote: > > On Wed, Jul 20, 2011 at 6:04 AM, Martin Langhoff <mar...@laptop.org> wrote: > > > On Wed, Jul 20, 2011 at 6:02 AM, Martin Langhoff <mar...@laptop.org> > > > wrote: > > >> ?- Updates olpc-utils to disable X zapping and fix serial port terminal > > > > > > Initial testing seems to indicate serial port needs a bit more > > > attention. I've also tested it with a newer kernel containing Paul's > > > tty config fix, and it doesn't make a difference. > > > > Looking at it again -- there is no apparent problem with using the > > serial port, only an early msg in var/log/messages > > > > Jul 21 04:07:36 localhost init: ttySx main process (33) terminated > > with status 1 > > I looked into this. > > /etc/init/ttyS.conf says "start on startup", but if it is changed to > "start on runlevel [12345]" this strange message goes away. Perhaps it
that would probably be okay. when i changed our conf file to "start on startup" a year or more ago, it was to get the serial port up as soon as possible, because i was tired of not having it while the system booted. (it was being treated as a normal user getty before that, i think.) paul > is caused by some interaction with upstart's init, or perhaps we are not > following best practices in ttyS.conf. > > (We have our own ttyS.conf, but curiously /etc/init/serial.conf might > have been starting a process, but it says it requires ttyS2 to be the > last or primary console in the kernel command line, and for it to be > listed in /etc/securetty. Doing those things doesn't cause serial.conf > to start a process though.) > > > But nothing seems to be broken > > > > - shutdown/reboot works correctly (and the plymouth workaround has > > been removed) > > - switch to gnome / sugar works correctly > > - bash is respawned correctly if you exit > > My gut feel is that we still have something lurking here, but nothing we > ship at the moment tries modem control on /dev/ttyS2. Not even > ModemManager, according to strace. (Pity it doesn't ignore USB serial > adapters as well.) > > I looked briefly at the serial/pxa driver. When a user process > configures for modem control on /dev/ttyS2 via termios, the upshot is > the setting of bit AFE (Auto-flow Control Enable) in the UART MCR (modem > control register). Good. > > During serial_pxa_startup, /dev/ttyS3 is configured for AFE > automatically. But I didn't see any obvious way at mmp2_add_uart time > to tell the driver not to bother setting UART_MCR_AFE for /dev/ttyS2. > > The control lines themselves aren't exposed, which is presumably why > threads that do I/O hang. > > But hey, the same thing happens on XO-1.5, just tested ... so we're good > to go. ;-) > > -- > James Cameron > http://quozl.linux.org.au/ > _______________________________________________ > Techteam mailing list > techt...@lists.laptop.org > http://lists.laptop.org/listinfo/techteam > _______________________________________________ > Engineering mailing list > engineer...@laptop.org > http://lists.laptop.org/listinfo/engineering =--------------------- paul fox, p...@laptop.org _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel