linux-toradex.git/include/linux/console.h, branch tegra-10.9.9

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

vt/vgacon: Check if screen resize request comes from userspace

2007-10-16T16:43:20+00:00

Various console drivers are able to resize the screen via the con_resize()
hook.  This hook is also visible in userspace via the TIOCWINSZ, VT_RESIZE and
VT_RESIZEX ioctl's.  One particular utility, SVGATextMode, expects that
con_resize() of the VGA console will always return success even if the
resulting screen is not compatible with the hardware.  However, this
particular behavior of the VGA console, as reported in Kernel Bugzilla Bug
7513, can cause undefined behavior if the user starts with a console size
larger than 80x25.

To work around this problem, add an extra parameter to con_resize().  This
parameter is ignored by drivers except for vgacon.  If this parameter is
non-zero, then the resize request came from a VT_RESIZE or VT_RESIZEX ioctl
and vgacon will always return success.  If this parameter is zero, vgacon will
return -EINVAL if the requested size is not compatible with the hardware.  The
latter is the more correct behavior.

With this change, SVGATextMode should still work correctly while in-kernel and
stty resize calls can expect correct behavior from vgacon.

Signed-off-by: Antonino Daplas 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Remove unnecessary includes of spinlock.h under include/linux

2007-07-16T16:05:42+00:00

Remove the obviously unnecessary includes of  under the
include/linux/ directory, and fix the couple errors that are introduced as
a result of that.

Signed-off-by: Robert P. J. Day 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

serial: convert early_uart to earlycon for 8250

2007-07-16T16:05:35+00:00

Beacuse SERIAL_PORT_DFNS is removed from include/asm-i386/serial.h and
include/asm-x86_64/serial.h.  the serial8250_ports need to be probed late in
serial initializing stage.  the console_init=>serial8250_console_init=>
register_console=>serial8250_console_setup will return -ENDEV, and console
ttyS0 can not be enabled at that time.  need to wait till uart_add_one_port in
drivers/serial/serial_core.c to call register_console to get console ttyS0.
that is too late.

Make early_uart to use early_param, so uart console can be used earlier.  Make
it to be bootconsole with CON_BOOT flag, so can use console handover feature.
and it will switch to corresponding normal serial console automatically.

new command line will be:
	console=uart8250,io,0x3f8,9600n8
	console=uart8250,mmio,0xff5e0000,115200n8
or
	earlycon=uart8250,io,0x3f8,9600n8
	earlycon=uart8250,mmio,0xff5e0000,115200n8

it will print in very early stage:
	Early serial console at I/O port 0x3f8 (options '9600n8')
	console [uart0] enabled
later for console it will print:
	console handover: boot [uart0] -> real [ttyS0]

Signed-off-by: 
Cc: Andi Kleen 
Cc: Bjorn Helgaas 
Cc: Russell King 
Cc: Gerd Hoffmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

vt: add color support to the "underline" and "italic" attributes

2007-05-08T18:15:27+00:00

Add color support to the "underline" and "italic" attributes as in
OpenBSD/NetBSD-style (vt220) and xterm.

Signed-off-by: Jan Engelhardt 
Acked-by: "Antonino A. Daplas" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

enlarge console.name

2007-05-08T18:15:04+00:00

console.name[] is eight chars, but so is "earlyvga".  So when we try to print
console->name when using earlyvga it runs off the end of the string.

Make it bigger.

Diagnosed-by: Gerd Hoffmann 

Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds