Messages in this thread | | | Date | Wed, 04 Jan 2012 21:54:29 +0100 | From | Jiri Slaby <> | Subject | Re: serial ports now asserting DTR and RTS during boot; breaks connected hardware |
| |
On 01/03/2012 05:06 PM, Alan Cox wrote: > On Tue, 3 Jan 2012 10:37:07 -0500 > Dave Jones <davej@redhat.com> wrote: > >> Jiri, >> We got this report from a user who notes a change in behaviour for >> his serial hardware over the last few kernel versions. >> >> https://bugzilla.redhat.com/show_bug.cgi?id=771010 >> >> This sounds like it might be related to your DTR/RTS changes back in March 2011 maybe ? > > Looks like your userspace to me at first glance. > > ftdi_sio sets up the modem lines in set_termios. Set_termios is called > from ftdi_open. ftdi_open is triggered by userspace. > >> > The following code in the ftdi_sio driver is one suspect but this behavior >> > happens on 8250 UARTs also so it is systemic now, > > Likewise 8250 sets up the lines in serial8250_startup. This is called via > uart_startup which is called via open.
Ok, let's apply the cut&paste rule. Does uninstalling ModemManager fix the issue?
-- js suse labs
| |