lkml.org 
[lkml]   [2019]   [Apr]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 47/57] docs: console.txt: convert to ReST format
Date
Convert this small file to ReST in preparation for adding it to
the driver-api book.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
---
Documentation/console/console.txt | 61 +++++++++++++++++--------------
1 file changed, 33 insertions(+), 28 deletions(-)

diff --git a/Documentation/console/console.txt b/Documentation/console/console.txt
index d73c2ab4beda..8b0205d27a71 100644
--- a/Documentation/console/console.txt
+++ b/Documentation/console/console.txt
@@ -1,3 +1,4 @@
+===============
Console Drivers
===============

@@ -17,25 +18,26 @@ of driver occupying the consoles.) They can only take over the console that is
occupied by the system driver. In the same token, if the modular driver is
released by the console, the system driver will take over.

-Modular drivers, from the programmer's point of view, have to call:
+Modular drivers, from the programmer's point of view, have to call::

do_take_over_console() - load and bind driver to console layer
give_up_console() - unload driver; it will only work if driver
is fully unbound

-In newer kernels, the following are also available:
+In newer kernels, the following are also available::

do_register_con_driver()
do_unregister_con_driver()

If sysfs is enabled, the contents of /sys/class/vtconsole can be
examined. This shows the console backends currently registered by the
-system which are named vtcon<n> where <n> is an integer from 0 to 15. Thus:
+system which are named vtcon<n> where <n> is an integer from 0 to 15.
+Thus::

ls /sys/class/vtconsole
. .. vtcon0 vtcon1

-Each directory in /sys/class/vtconsole has 3 files:
+Each directory in /sys/class/vtconsole has 3 files::

ls /sys/class/vtconsole/vtcon0
. .. bind name uevent
@@ -46,27 +48,29 @@ What do these files signify?
read, or acts to bind or unbind the driver to the virtual consoles
when written to. The possible values are:

- 0 - means the driver is not bound and if echo'ed, commands the driver
+ 0
+ - means the driver is not bound and if echo'ed, commands the driver
to unbind

- 1 - means the driver is bound and if echo'ed, commands the driver to
+ 1
+ - means the driver is bound and if echo'ed, commands the driver to
bind

- 2. name - read-only file. Shows the name of the driver in this format:
+ 2. name - read-only file. Shows the name of the driver in this format::

- cat /sys/class/vtconsole/vtcon0/name
- (S) VGA+
+ cat /sys/class/vtconsole/vtcon0/name
+ (S) VGA+

- '(S)' stands for a (S)ystem driver, i.e., it cannot be directly
- commanded to bind or unbind
+ '(S)' stands for a (S)ystem driver, i.e., it cannot be directly
+ commanded to bind or unbind

- 'VGA+' is the name of the driver
+ 'VGA+' is the name of the driver

- cat /sys/class/vtconsole/vtcon1/name
- (M) frame buffer device
+ cat /sys/class/vtconsole/vtcon1/name
+ (M) frame buffer device

- In this case, '(M)' stands for a (M)odular driver, one that can be
- directly commanded to bind or unbind.
+ In this case, '(M)' stands for a (M)odular driver, one that can be
+ directly commanded to bind or unbind.

3. uevent - ignore this file

@@ -75,14 +79,17 @@ driver takes over the consoles vacated by the driver. Binding, on the other
hand, will bind the driver to the consoles that are currently occupied by a
system driver.

-NOTE1: Binding and unbinding must be selected in Kconfig. It's under:
+NOTE1:
+ Binding and unbinding must be selected in Kconfig. It's under::

-Device Drivers -> Character devices -> Support for binding and unbinding
-console drivers
+ Device Drivers ->
+ Character devices ->
+ Support for binding and unbinding console drivers

-NOTE2: If any of the virtual consoles are in KD_GRAPHICS mode, then binding or
-unbinding will not succeed. An example of an application that sets the console
-to KD_GRAPHICS is X.
+NOTE2:
+ If any of the virtual consoles are in KD_GRAPHICS mode, then binding or
+ unbinding will not succeed. An example of an application that sets the
+ console to KD_GRAPHICS is X.

How useful is this feature? This is very useful for console driver
developers. By unbinding the driver from the console layer, one can unload the
@@ -92,10 +99,10 @@ framebuffer console to VGA console and vice versa, this feature also makes
this possible. (NOTE NOTE NOTE: Please read fbcon.txt under Documentation/fb
for more details.)

-Notes for developers:
-=====================
+Notes for developers
+====================

-do_take_over_console() is now broken up into:
+do_take_over_console() is now broken up into::

do_register_con_driver()
do_bind_con_driver() - private function
@@ -104,7 +111,7 @@ give_up_console() is a wrapper to do_unregister_con_driver(), and a driver must
be fully unbound for this call to succeed. con_is_bound() will check if the
driver is bound or not.

-Guidelines for console driver writers:
+Guidelines for console driver writers
=====================================

In order for binding to and unbinding from the console to properly work,
@@ -140,6 +147,4 @@ The current crop of console drivers should still work correctly, but binding
and unbinding them may cause problems. With minimal fixes, these drivers can
be made to work correctly.

-==========================
Antonino Daplas <adaplas@pol.net>
-
--
2.20.1
\
 
 \ /
  Last update: 2019-04-16 04:57    [W:0.181 / U:7.048 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site