linux-toradex.git/include/linux/console.h, branch Colibri_T30_LinuxImageV2.1Beta2_20140206

console: rename acquire/release_console_sem() to console_lock/unlock()

2011-01-26T00:50:06+00:00

The -rt patches change the console_semaphore to console_mutex.  As a
result, a quite large chunk of the patches changes all
acquire/release_console_sem() to acquire/release_console_mutex()

This commit makes things use more neutral function names which dont make
implications about the underlying lock.

The only real change is the return value of console_trylock which is
inverted from try_acquire_console_sem()

This patch also paves the way to switching console_sem from a semaphore to
a mutex.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make console_trylock return 1 on success, per Geert]
Signed-off-by: Torben Hohn 
Cc: Thomas Gleixner 
Cc: Greg KH 
Cc: Ingo Molnar 
Cc: Geert Uytterhoeven 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

tty: add 'active' sysfs attribute to tty0 and console device

2010-12-17T00:15:34+00:00

tty: add 'active' sysfs attribute to tty0 and console device

Userspace can query the actual virtual console, and the configured
console devices behind /dev/tt0 and /dev/console.

The last entry in the list of devices is the active device, analog
to the console= kernel command line option.

The attribute supports poll(), which is raised when the virtual
console is changed or /dev/console is reconfigured.

Signed-off-by: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman 

index 0000000..b138b66

console: move for_each_console to linux/console.h

2010-11-16T20:50:17+00:00

Move it out of printk.c so that we can use it all over the code. There
are some potential users which will be converted to that macro in next
patches.

Signed-off-by: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman

console: Fix compilation regression

2010-08-06T20:36:47+00:00

A regression of building without CONFIG_HW_CONSOLE was introduced with
commit b45cfba4e9005d64d419718e7ff7f7cab44c1994 (vt,console,kdb:
implement atomic console enter/leave functions).

ERROR: "con_debug_enter" [drivers/serial/kgdboc.ko] undefined!
ERROR: "vc_cons" [drivers/serial/kgdboc.ko] undefined!
ERROR: "fg_console" [drivers/serial/kgdboc.ko] undefined!
ERROR: "con_debug_leave" [drivers/serial/kgdboc.ko] undefined!

When there is no HW console the con_debug_enter and con_debug_leave
functions should have no code.

Signed-off-by: Jason Wessel 
CC: Jesse Barnes 
Reported-by: Randy Dunlap

vt,console,kdb: implement atomic console enter/leave functions

2010-08-05T14:22:30+00:00

These functions allow the kernel debugger to save and restore the
state of the system console.

Signed-off-by: Jesse Barnes 
Signed-off-by: Jason Wessel 
CC: David Airlie 
CC: Andrew Morton

vcs: hook sysfs devices into object lifetime instead of "binding"

2009-03-24T23:38:26+00:00

During bootup performance tracing I noticed many occurrences of
vca* device creation and removal, leading to the usual userspace
uevent processing, which are, in this case, rather pointless.

A simple test showing the kernel timing (not including all the
work userspace has to do), gives us these numbers:
  $ time for i in `seq 1000`; do echo a > /dev/tty2; done
  real    0m1.142s
  user    0m0.015s
  sys     0m0.540s

If we move the hook for the vcs* driver core devices from the
tty "binding" to the vc allocation/deallocation, which is what
the vcs* devices represent, we get the following numbers:
  $ time for i in `seq 1000`; do echo a > /dev/tty2; done
  real    0m0.152s
  user    0m0.030s
  sys     0m0.072s

Cc: Alan Cox 
Signed-off-by: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman

DRM: add mode setting support

2008-12-29T07:47:23+00:00

Add mode setting support to the DRM layer.

This is a fairly big chunk of work that allows DRM drivers to provide
full output control and configuration capabilities to userspace.  It was
motivated by several factors:
  - the fb layer's APIs aren't suited for anything but simple
    configurations
  - coordination between the fb layer, DRM layer, and various userspace
    drivers is poor to non-existent (radeonfb excepted)
  - user level mode setting drivers makes displaying panic & oops
    messages more difficult
  - suspend/resume of graphics state is possible in many more
    configurations with kernel level support

This commit just adds the core DRM part of the mode setting APIs.
Driver specific commits using these new structure and APIs will follow.

Co-authors: Jesse Barnes , Jakob Bornecrantz 
Contributors: Alan Hourihane , Maarten Maathuis 

Signed-off-by: Jesse Barnes 
Signed-off-by: Eric Anholt 
Signed-off-by: Dave Airlie

xen: Enable console tty by default in domU if it's not a dummy

2008-05-27T08:11:36+00:00

Without console= arguments on the kernel command line, the first
console to register becomes enabled and the preferred console (the one
behind /dev/console).  This is normally tty (assuming
CONFIG_VT_CONSOLE is enabled, which it commonly is).

This is okay as long tty is a useful console.  But unless we have the
PV framebuffer, and it is enabled for this domain, tty0 in domU is
merely a dummy.  In that case, we want the preferred console to be the
Xen console hvc0, and we want it without having to fiddle with the
kernel command line.  Commit b8c2d3dfbc117dff26058fbac316b8acfc2cb5f7
did that for us.

Since we now have the PV framebuffer, we want to enable and prefer tty
again, but only when PVFB is enabled.  But even then we still want to
enable the Xen console as well.

Problem: when tty registers, we can't yet know whether the PVFB is
enabled.  By the time we can know (xenstore is up), the console setup
game is over.

Solution: enable console tty by default, but keep hvc as the preferred
console.  Change the preferred console to tty when PVFB probes
successfully, unless we've been given console kernel parameters.

Signed-off-by: Markus Armbruster 
Signed-off-by: Jeremy Fitzhardinge 
Signed-off-by: Thomas Gleixner

Basic braille screen reader support

2008-04-30T15:29:52+00:00

This adds a minimalistic braille screen reader support.  This is meant to
be used by blind people e.g.  on boot failures or when / cannot be mounted
etc and thus the userland screen readers can not work.

[akpm@linux-foundation.org: fix exports]
Signed-off-by: Samuel Thibault 
Cc: Jiri Kosina 
Cc: Dmitry Torokhov 
Acked-by: Alan Cox 
Cc: Randy Dunlap 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

serial: turn serial console suspend a boot rather than compile time option

2007-10-18T21:37:19+00:00

Currently, there's a CONFIG_DISABLE_CONSOLE_SUSPEND that allows one to stop
the serial console from being suspended when the rest of the machine goes
to sleep.  This is incredibly useful for debugging power management-related
things; however, having it as a compile-time option has proved to be
incredibly inconvenient for us (OLPC).  There are plenty of times that we
want serial console to not suspend, but for the most part we'd like serial
console to be suspended.

This drops CONFIG_DISABLE_CONSOLE_SUSPEND, and replaces it with a kernel
boot parameter (no_console_suspend).  By default, the serial console will
be suspended along with the rest of the system; by passing
'no_console_suspend' to the kernel during boot, serial console will remain
alive during suspend.

For now, this is pretty serial console specific; further fixes could be
applied to make this work for things like netconsole.

Signed-off-by: Andres Salomon 
Acked-by: "Rafael J. Wysocki" 
Acked-by: Pavel Machek 
Cc: Nigel Cunningham 
Cc: Russell King 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds