linux-toradex.git/drivers/char/tty_port.c, branch v2.6.35.8 Linux kernel for Apalis and Colibri modules tty_port,usb-console: Fix usb serial console open/close regression 2010-03-19T14:17:57+00:00 Jason Wessel jason.wessel@windriver.com 2010-03-09T03:50:11+00:00 336cee42dd52824e360ab419eab4e8888eb054ec Commit e1108a63e10d344284011cccc06328b2cd3e5da3 ("usb_serial: Use the shutdown() operation") breaks the ability to use a usb console starting in 2.6.33. This was observed when using console=ttyUSB0,115200 as a boot argument with an FTDI device. The error is: ftdi_sio ttyUSB0: ftdi_submit_read_urb - failed submitting read urb, error -22 The handling of the ASYNCB_INITIALIZED changed in 2.6.32 such that in tty_port_shutdown() it always clears the flag if it is set. The fix is to add a variable to the tty_port struct to indicate when the tty port is a console. CC: Alan Cox <alan@linux.intel.com> CC: Alan Stern <stern@rowland.harvard.edu> CC: Oliver Neukum <oliver@neukum.org> CC: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
Commit e1108a63e10d344284011cccc06328b2cd3e5da3 ("usb_serial: Use the
shutdown() operation") breaks the ability to use a usb console
starting in 2.6.33.  This was observed when using
console=ttyUSB0,115200 as a boot argument with an FTDI device.  The
error is:

ftdi_sio ttyUSB0: ftdi_submit_read_urb - failed submitting read urb, error -22

The handling of the ASYNCB_INITIALIZED changed in 2.6.32 such that in
tty_port_shutdown() it always clears the flag if it is set.  The fix
is to add a variable to the tty_port struct to indicate when the tty
port is a console.

CC: Alan Cox <alan@linux.intel.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Oliver Neukum <oliver@neukum.org>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty: tty_port: Add a kref object to the tty port 2009-12-11T23:18:07+00:00 Alan Cox alan@linux.intel.com 2009-11-30T13:17:14+00:00 568aafc627e2978509e8a80c640ba534d1e843cc Users of tty port need a way to refcount ports when hotplugging is involved. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
Users of tty port need a way to refcount ports when hotplugging is
involved.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty: tty_port: Move the IO_ERROR clear 2009-12-11T23:18:06+00:00 Alan Cox alan@linux.intel.com 2009-11-30T13:16:57+00:00 a9a37ec33a1b3e66b260ac1c29bff0aec8b89ae4 Some devices want to set IO_ERROR in their activate methods so that you can be handed a 'dead' port for operations like setserial. Thus we need to clear the flag before activate so that activate can choose to set the flag and still return 0. This is fine as the file handle/tty are not accessible to the user yet. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
Some devices want to set IO_ERROR in their activate methods so that you can
be handed a 'dead' port for operations like setserial. Thus we need to
clear the flag before activate so that activate can choose to set the flag
and still return 0.

This is fine as the file handle/tty are not accessible to the user yet.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty: tty_port: Add IO_ERROR bit handling 2009-12-11T23:18:06+00:00 Alan Cox alan@linux.intel.com 2009-11-30T13:16:52+00:00 d74e8286885ac9f3ccc5e2dc2301f21bbec90f7b To propogate tty_port_open/close to a few other devices we need to start handling the IO_ERROR flag on the tty. We can do this pretty trivially. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
To propogate tty_port_open/close to a few other devices we need to start
handling the IO_ERROR flag on the tty. We can do this pretty trivially.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty: tty_port: Change the buffer allocator locking 2009-12-11T23:18:06+00:00 Alan Cox alan@linux.intel.com 2009-11-30T13:16:41+00:00 44e4909e453eaa09c7de409fc9ee4ebefd986c1c We want to be able to do this without regard for the activate/own open method being used which causes a problem using port->mutex. Add another mutex for now. Once everything uses port_open to do buffer allocs we can kill it back off Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
We want to be able to do this without regard for the activate/own open
method being used which causes a problem using port->mutex. Add another
mutex for now. Once everything uses port_open to do buffer allocs we can
kill it back off

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty_port: Move hupcl handling 2009-12-11T23:18:05+00:00 Alan Cox alan@linux.intel.com 2009-11-05T13:27:57+00:00 e707c35cbbe83a016cf0122a29e3a47b5a9e35c4 Move the HUCPL handling from the end of close_port_start to the beginning of close_port_end. What this actually does is change the ordering from port shutdown port->dtr_rts to port->dtr_rts port shutdown Some hardware drops the physical connection on shutdown so we must perform the port operations before the shutdown. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
Move the HUCPL handling from the end of close_port_start to the beginning
of close_port_end. What this actually does is change the ordering from

	port shutdown
	port->dtr_rts

to

	port->dtr_rts
	port shutdown

Some hardware drops the physical connection on shutdown so we must perform
the port operations before the shutdown.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty_port: coding style cleaning pass 2009-12-11T23:18:04+00:00 Alan Cox alan@linux.intel.com 2009-10-06T15:06:21+00:00 d774a56d2353933cf21cc92a9d0012c7b69d09bf Mind the hoover wire... Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Oliver Neukum <oliver@neukum.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
Mind the hoover wire...

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty_port: add "tty_port_open" helper 2009-12-11T23:18:04+00:00 Alan Cox alan@linux.intel.com 2009-10-06T15:06:11+00:00 64bc397914265a9ead8d73b63bb31ab3bdd25f67 For the moment this just moves the USB logic over and fixes the 'what if we open and hangup at the same time' race noticed by Oliver Neukum. Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Oliver Neukum <oliver@neukum.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
For the moment this just moves the USB logic over and fixes the 'what if
we open and hangup at the same time' race noticed by Oliver Neukum.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty_port: handle the nonblocking open of a dead port corner case 2009-12-01T00:38:25+00:00 Alan Cox alan@linux.intel.com 2009-11-18T14:12:58+00:00 8627b96dd80dca440d91fbb1ec733be25912d0dd Some drivers allow O_NDELAY of a dead port (eg for setserial to work). In that situation we must not try to raise the carrier. Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
Some drivers allow O_NDELAY of a dead port (eg for setserial to work). In that
situation we must not try to raise the carrier.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
tty_port: If we are opened non blocking we still need to raise the carrier 2009-11-18T00:42:28+00:00 Alan Cox alan@linux.intel.com 2009-10-28T20:12:32+00:00 4175f3e31cc7157669aa66d46dc79de6ae0126ce Original discussion: http://thread.gmane.org/gmane.linux.usb.general/23217/focus=23248 or http://marc.info/?l=linux-usb&m=125553790714133&w=2 The tty_port code inherited a bug common to various drivers it was based upon. If the tty is opened O_NONBLOCK we do not wait for the carrier to be raised but we must still raise our modem lines if appropriate. (There is a second question here about whether we should do so if CLOCAL is set but that can wait) Signed-off-by: Alan Cox <alan@linux.intel.com> Reported-by: Karl Hiramoto <karl@hiramoto.org> Tested-by: Karl Hiramoto <karl@hiramoto.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
Original discussion:
http://thread.gmane.org/gmane.linux.usb.general/23217/focus=23248
or
http://marc.info/?l=linux-usb&m=125553790714133&w=2

The tty_port code inherited a bug common to various drivers it was based
upon. If the tty is opened O_NONBLOCK we do not wait for the carrier to be
raised but we must still raise our modem lines if appropriate.

(There is a second question here about whether we should do so if CLOCAL is
 set but that can wait)

Signed-off-by: Alan Cox <alan@linux.intel.com>
Reported-by: Karl Hiramoto <karl@hiramoto.org>
Tested-by:  Karl Hiramoto <karl@hiramoto.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>