From: Changbin Du <changbin.du@gmail.com>
To: Jonathan Corbet <corbet@lwn.net>
Cc: rjw@rjwysocki.net, lenb@kernel.org, linux-acpi@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
Changbin Du <changbin.du@gmail.com>
Subject: [PATCH 23/23] acpi doc: convert acpi/video_extension.txt to rst format
Date: Fri, 29 Mar 2019 00:27:21 +0800 [thread overview]
Message-ID: <20190328162721.26138-24-changbin.du@gmail.com> (raw)
In-Reply-To: <20190328162721.26138-1-changbin.du@gmail.com>
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
---
Documentation/acpi/index.rst | 1 +
...ideo_extension.txt => video_extension.rst} | 61 ++++++++++---------
2 files changed, 34 insertions(+), 28 deletions(-)
rename Documentation/acpi/{video_extension.txt => video_extension.rst} (80%)
diff --git a/Documentation/acpi/index.rst b/Documentation/acpi/index.rst
index 7909199e16ff..1b96562d5c5b 100644
--- a/Documentation/acpi/index.rst
+++ b/Documentation/acpi/index.rst
@@ -27,3 +27,4 @@ Linux ACPI (Advanced Configuration and Power Interface)
cppc_sysfs
lpit
ssdt-overlays
+ video_extension
diff --git a/Documentation/acpi/video_extension.txt b/Documentation/acpi/video_extension.rst
similarity index 80%
rename from Documentation/acpi/video_extension.txt
rename to Documentation/acpi/video_extension.rst
index 79bf6a4921be..842c72aad2ae 100644
--- a/Documentation/acpi/video_extension.txt
+++ b/Documentation/acpi/video_extension.rst
@@ -1,5 +1,6 @@
+=====================
ACPI video extensions
-~~~~~~~~~~~~~~~~~~~~~
+=====================
This driver implement the ACPI Extensions For Display Adapters for
integrated graphics devices on motherboard, as specified in ACPI 2.0
@@ -8,9 +9,10 @@ defining the video POST device, retrieving EDID information or to
setup a video output, etc. Note that this is an ref. implementation
only. It may or may not work for your integrated video device.
-The ACPI video driver does 3 things regarding backlight control:
+The ACPI video driver does 3 things regarding backlight control.
-1 Export a sysfs interface for user space to control backlight level
+1. Export a sysfs interface for user space to control backlight level
+=====================================================================
If the ACPI table has a video device, and acpi_backlight=vendor kernel
command line is not present, the driver will register a backlight device
@@ -32,26 +34,26 @@ type: firmware
Note that ACPI video backlight driver will always use index for
brightness, actual_brightness and max_brightness. So if we have
-the following _BCL package:
+the following _BCL package::
-Method (_BCL, 0, NotSerialized)
-{
- Return (Package (0x0C)
+ Method (_BCL, 0, NotSerialized)
{
- 0x64,
- 0x32,
- 0x0A,
- 0x14,
- 0x1E,
- 0x28,
- 0x32,
- 0x3C,
- 0x46,
- 0x50,
- 0x5A,
- 0x64
- })
-}
+ Return (Package (0x0C)
+ {
+ 0x64,
+ 0x32,
+ 0x0A,
+ 0x14,
+ 0x1E,
+ 0x28,
+ 0x32,
+ 0x3C,
+ 0x46,
+ 0x50,
+ 0x5A,
+ 0x64
+ })
+ }
The first two levels are for when laptop are on AC or on battery and are
not used by Linux currently. The remaining 10 levels are supported levels
@@ -62,13 +64,15 @@ as a "brightness level" indicator. Thus from the user space perspective
the range of available brightness levels is from 0 to 9 (max_brightness)
inclusive.
-2 Notify user space about hotkey event
+2. Notify user space about hotkey event
+=======================================
There are generally two cases for hotkey event reporting:
+
i) For some laptops, when user presses the hotkey, a scancode will be
generated and sent to user space through the input device created by
the keyboard driver as a key type input event, with proper remap, the
- following key code will appear to user space:
+ following key code will appear to user space::
EV_KEY, KEY_BRIGHTNESSUP
EV_KEY, KEY_BRIGHTNESSDOWN
@@ -82,7 +86,7 @@ ii) For some laptops, the press of the hotkey will not generate the
about the event. The event value is defined in the ACPI spec. ACPI
video driver will generate an key type input event according to the
notify value it received and send the event to user space through the
- input device it created:
+ input device it created::
event keycode
0x86 KEY_BRIGHTNESSUP
@@ -94,13 +98,14 @@ so this would lead to the same effect as case i) now.
Once user space tool receives this event, it can modify the backlight
level through the sysfs interface.
-3 Change backlight level in the kernel
+3. Change backlight level in the kernel
+=======================================
This works for machines covered by case ii) in Section 2. Once the driver
received a notification, it will set the backlight level accordingly. This does
not affect the sending of event to user space, they are always sent to user
space regardless of whether or not the video module controls the backlight level
directly. This behaviour can be controlled through the brightness_switch_enabled
-module parameter as documented in admin-guide/kernel-parameters.rst. It is recommended to
-disable this behaviour once a GUI environment starts up and wants to have full
-control of the backlight level.
+module parameter as documented in admin-guide/kernel-parameters.rst. It is
+recommended to disable this behaviour once a GUI environment starts up and
+wants to have full control of the backlight level.
--
2.20.1
next prev parent reply other threads:[~2019-03-28 16:30 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-28 16:26 [PATCH 00/23] Include linux ACPI docs into Sphinx TOC tree Changbin Du
2019-03-28 16:26 ` [PATCH 01/23] Documentation: add Linux ACPI to " Changbin Du
2019-03-28 16:27 ` [PATCH 02/23] acpi doc: convert acpi/namespace.txt to rst format Changbin Du
2019-03-28 16:27 ` [PATCH 03/23] acpi doc: convert acpi/enumeration.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 04/23] acpi doc: convert acpi/osi.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 05/23] acpi doc: convert acpi/linuxized-acpica.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 06/23] acpi doc: convert acpi/scan_handlers.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 07/23] acpi doc: convert acpi/DSD-properties-rules.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 08/23] acpi doc: convert acpi/gpio-properties.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 09/23] acpi doc: convert acpi/method-customizing.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 10/23] acpi doc: convert acpi/initrd_table_override.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 11/23] acpi doc: convert acpi/dsdt-override.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 12/23] acpi doc: convert acpi/i2c-muxes.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 13/23] acpi doc: convert acpi/acpi-lid.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 14/23] acpi doc: convert acpi/dsd/graph.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 15/23] acpi doc: convert acpi/debug.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 16/23] acpi doc: convert acpi/method-tracing.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 17/23] acpi doc: convert acpi/aml-debugger.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 18/23] acpi doc: convert acpi/apei/output_format.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 19/23] acpi doc: convert acpi/apei/einj.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 20/23] acpi doc: convert acpi/cppc_sysfs.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 21/23] acpi doc: convert acpi/lpit.txt " Changbin Du
2019-03-28 16:27 ` [PATCH 22/23] acpi doc: convert acpi/ssdt-overlays.txt " Changbin Du
2019-03-28 16:27 ` Changbin Du [this message]
2019-03-28 16:34 ` [PATCH 00/23] Include linux ACPI docs into Sphinx TOC tree Joe Perches
2019-03-29 0:08 ` Changbin Du
2019-03-28 16:39 ` Jonathan Corbet
2019-03-29 0:10 ` Changbin Du
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190328162721.26138-24-changbin.du@gmail.com \
--to=changbin.du@gmail.com \
--cc=corbet@lwn.net \
--cc=lenb@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rjw@rjwysocki.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).