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authorLinus Torvalds <torvalds@linux-foundation.org>2019-12-02 11:51:02 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-12-02 11:51:02 -0800
commit937d6eefc716a9071f0e3bada19200de1bb9d048 (patch)
tree7b2b8e94d157ddbacc2b0712fd5d20a8b4d79c27 /Documentation/driver-api
parent2c97b5ae83dca56718774e7b4bf9640f05d11867 (diff)
parent36bb9778fd11173f2dd1484e4f6797365e18c1d8 (diff)
Merge tag 'docs-5.5a' of git://git.lwn.net/linux
Pull Documentation updates from Jonathan Corbet: "Here are the main documentation changes for 5.5: - Various kerneldoc script enhancements. - More RST conversions; those are slowing down as we run out of things to convert, but we're a ways from done still. - Dan's "maintainer profile entry" work landed at last. Now we just need to get maintainers to fill in the profiles... - A reworking of the parallel build setup to work better with a variety of systems (and to not take over huge systems entirely in particular). - The MAINTAINERS file is now converted to RST during the build. Hopefully nobody ever tries to print this thing, or they will need to load a lot of paper. - A script and documentation making it easy for maintainers to add Link: tags at commit time. Also included is the removal of a bunch of spurious CR characters" * tag 'docs-5.5a' of git://git.lwn.net/linux: (91 commits) docs: remove a bunch of stray CRs docs: fix up the maintainer profile document libnvdimm, MAINTAINERS: Maintainer Entry Profile Maintainer Handbook: Maintainer Entry Profile MAINTAINERS: Reclaim the P: tag for Maintainer Entry Profile docs, parallelism: Rearrange how jobserver reservations are made docs, parallelism: Do not leak blocking mode to other readers docs, parallelism: Fix failure path and add comment Documentation: Remove bootmem_debug from kernel-parameters.txt Documentation: security: core.rst: fix warnings Documentation/process/howto/kokr: Update for 4.x -> 5.x versioning Documentation/translation: Use Korean for Korean translation title docs/memory-barriers.txt: Remove remaining references to mmiowb() docs/memory-barriers.txt/kokr: Update I/O section to be clearer about CPU vs thread docs/memory-barriers.txt/kokr: Fix style, spacing and grammar in I/O section Documentation/kokr: Kill all references to mmiowb() docs/memory-barriers.txt/kokr: Rewrite "KERNEL I/O BARRIER EFFECTS" section docs: Add initial documentation for devfreq Documentation: Document how to get links with git am docs: Add request_irq() documentation ...
Diffstat (limited to 'Documentation/driver-api')
-rw-r--r--Documentation/driver-api/dell_rbu.rst128
-rw-r--r--Documentation/driver-api/devfreq.rst30
-rw-r--r--Documentation/driver-api/gpio/driver.rst2
-rw-r--r--Documentation/driver-api/index.rst3
-rw-r--r--Documentation/driver-api/infrastructure.rst3
-rw-r--r--Documentation/driver-api/interconnect.rst2
-rw-r--r--Documentation/driver-api/pti_intel_mid.rst4
7 files changed, 36 insertions, 136 deletions
diff --git a/Documentation/driver-api/dell_rbu.rst b/Documentation/driver-api/dell_rbu.rst
deleted file mode 100644
index 5d1ce7bcd04d..000000000000
--- a/Documentation/driver-api/dell_rbu.rst
+++ /dev/null
@@ -1,128 +0,0 @@
-=============================================================
-Usage of the new open sourced rbu (Remote BIOS Update) driver
-=============================================================
-
-Purpose
-=======
-
-Document demonstrating the use of the Dell Remote BIOS Update driver.
-for updating BIOS images on Dell servers and desktops.
-
-Scope
-=====
-
-This document discusses the functionality of the rbu driver only.
-It does not cover the support needed from applications to enable the BIOS to
-update itself with the image downloaded in to the memory.
-
-Overview
-========
-
-This driver works with Dell OpenManage or Dell Update Packages for updating
-the BIOS on Dell servers (starting from servers sold since 1999), desktops
-and notebooks (starting from those sold in 2005).
-
-Please go to http://support.dell.com register and you can find info on
-OpenManage and Dell Update packages (DUP).
-
-Libsmbios can also be used to update BIOS on Dell systems go to
-http://linux.dell.com/libsmbios/ for details.
-
-Dell_RBU driver supports BIOS update using the monolithic image and packetized
-image methods. In case of monolithic the driver allocates a contiguous chunk
-of physical pages having the BIOS image. In case of packetized the app
-using the driver breaks the image in to packets of fixed sizes and the driver
-would place each packet in contiguous physical memory. The driver also
-maintains a link list of packets for reading them back.
-
-If the dell_rbu driver is unloaded all the allocated memory is freed.
-
-The rbu driver needs to have an application (as mentioned above)which will
-inform the BIOS to enable the update in the next system reboot.
-
-The user should not unload the rbu driver after downloading the BIOS image
-or updating.
-
-The driver load creates the following directories under the /sys file system::
-
- /sys/class/firmware/dell_rbu/loading
- /sys/class/firmware/dell_rbu/data
- /sys/devices/platform/dell_rbu/image_type
- /sys/devices/platform/dell_rbu/data
- /sys/devices/platform/dell_rbu/packet_size
-
-The driver supports two types of update mechanism; monolithic and packetized.
-These update mechanism depends upon the BIOS currently running on the system.
-Most of the Dell systems support a monolithic update where the BIOS image is
-copied to a single contiguous block of physical memory.
-
-In case of packet mechanism the single memory can be broken in smaller chunks
-of contiguous memory and the BIOS image is scattered in these packets.
-
-By default the driver uses monolithic memory for the update type. This can be
-changed to packets during the driver load time by specifying the load
-parameter image_type=packet. This can also be changed later as below::
-
- echo packet > /sys/devices/platform/dell_rbu/image_type
-
-In packet update mode the packet size has to be given before any packets can
-be downloaded. It is done as below::
-
- echo XXXX > /sys/devices/platform/dell_rbu/packet_size
-
-In the packet update mechanism, the user needs to create a new file having
-packets of data arranged back to back. It can be done as follows
-The user creates packets header, gets the chunk of the BIOS image and
-places it next to the packetheader; now, the packetheader + BIOS image chunk
-added together should match the specified packet_size. This makes one
-packet, the user needs to create more such packets out of the entire BIOS
-image file and then arrange all these packets back to back in to one single
-file.
-
-This file is then copied to /sys/class/firmware/dell_rbu/data.
-Once this file gets to the driver, the driver extracts packet_size data from
-the file and spreads it across the physical memory in contiguous packet_sized
-space.
-
-This method makes sure that all the packets get to the driver in a single operation.
-
-In monolithic update the user simply get the BIOS image (.hdr file) and copies
-to the data file as is without any change to the BIOS image itself.
-
-Do the steps below to download the BIOS image.
-
-1) echo 1 > /sys/class/firmware/dell_rbu/loading
-2) cp bios_image.hdr /sys/class/firmware/dell_rbu/data
-3) echo 0 > /sys/class/firmware/dell_rbu/loading
-
-The /sys/class/firmware/dell_rbu/ entries will remain till the following is
-done.
-
-::
-
- echo -1 > /sys/class/firmware/dell_rbu/loading
-
-Until this step is completed the driver cannot be unloaded.
-
-Also echoing either mono, packet or init in to image_type will free up the
-memory allocated by the driver.
-
-If a user by accident executes steps 1 and 3 above without executing step 2;
-it will make the /sys/class/firmware/dell_rbu/ entries disappear.
-
-The entries can be recreated by doing the following::
-
- echo init > /sys/devices/platform/dell_rbu/image_type
-
-.. note:: echoing init in image_type does not change it original value.
-
-Also the driver provides /sys/devices/platform/dell_rbu/data readonly file to
-read back the image downloaded.
-
-.. note::
-
- After updating the BIOS image a user mode application needs to execute
- code which sends the BIOS update request to the BIOS. So on the next reboot
- the BIOS knows about the new image downloaded and it updates itself.
- Also don't unload the rbu driver if the image has to be updated.
-
diff --git a/Documentation/driver-api/devfreq.rst b/Documentation/driver-api/devfreq.rst
new file mode 100644
index 000000000000..4a0bf87a3b13
--- /dev/null
+++ b/Documentation/driver-api/devfreq.rst
@@ -0,0 +1,30 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+========================
+Device Frequency Scaling
+========================
+
+Introduction
+------------
+
+This framework provides a standard kernel interface for Dynamic Voltage and
+Frequency Switching on arbitrary devices.
+
+It exposes controls for adjusting frequency through sysfs files which are
+similar to the cpufreq subsystem.
+
+Devices for which current usage can be measured can have their frequency
+automatically adjusted by governors.
+
+API
+---
+
+Device drivers need to initialize a :c:type:`devfreq_profile` and call the
+:c:func:`devfreq_add_device` function to create a :c:type:`devfreq` instance.
+
+.. kernel-doc:: include/linux/devfreq.h
+.. kernel-doc:: include/linux/devfreq-event.h
+.. kernel-doc:: drivers/devfreq/devfreq.c
+ :export:
+.. kernel-doc:: drivers/devfreq/devfreq-event.c
+ :export:
diff --git a/Documentation/driver-api/gpio/driver.rst b/Documentation/driver-api/gpio/driver.rst
index 10ef357ef658..2ff743105927 100644
--- a/Documentation/driver-api/gpio/driver.rst
+++ b/Documentation/driver-api/gpio/driver.rst
@@ -500,7 +500,7 @@ available but we try to move away from this:
gpiochip. It will pass the struct gpio_chip* for the chip to all IRQ
callbacks, so the callbacks need to embed the gpio_chip in its state
container and obtain a pointer to the container using container_of().
- (See Documentation/driver-model/design-patterns.txt)
+ (See Documentation/driver-api/driver-model/design-patterns.rst)
- gpiochip_irqchip_add_nested(): adds a nested cascaded irqchip to a gpiochip,
as discussed above regarding different types of cascaded irqchips. The
diff --git a/Documentation/driver-api/index.rst b/Documentation/driver-api/index.rst
index 3bcd9a13fbb3..0ebe205efd0c 100644
--- a/Documentation/driver-api/index.rst
+++ b/Documentation/driver-api/index.rst
@@ -40,6 +40,7 @@ available subsections can be seen below.
ipmb
i3c/index
interconnect
+ devfreq
hsi
edac
scsi
@@ -73,7 +74,6 @@ available subsections can be seen below.
connector
console
dcdbas
- dell_rbu
edid
eisa
ipmb
@@ -93,7 +93,6 @@ available subsections can be seen below.
pwm
rfkill
serial/index
- sgi-ioc4
sm501
smsc_ece1099
switchtec
diff --git a/Documentation/driver-api/infrastructure.rst b/Documentation/driver-api/infrastructure.rst
index 6172f3cc3d0b..06d98c4526df 100644
--- a/Documentation/driver-api/infrastructure.rst
+++ b/Documentation/driver-api/infrastructure.rst
@@ -49,9 +49,6 @@ Device Drivers Base
Device Drivers DMA Management
-----------------------------
-.. kernel-doc:: kernel/dma/coherent.c
- :export:
-
.. kernel-doc:: kernel/dma/mapping.c
:export:
diff --git a/Documentation/driver-api/interconnect.rst b/Documentation/driver-api/interconnect.rst
index c3e004893796..cdeb5825f314 100644
--- a/Documentation/driver-api/interconnect.rst
+++ b/Documentation/driver-api/interconnect.rst
@@ -1,7 +1,7 @@
.. SPDX-License-Identifier: GPL-2.0
=====================================
-GENERIC SYSTEM INTERCONNECT SUBSYSTEM
+Generic System Interconnect Subsystem
=====================================
Introduction
diff --git a/Documentation/driver-api/pti_intel_mid.rst b/Documentation/driver-api/pti_intel_mid.rst
index 20f1cff42d5f..bacc2a4ee89f 100644
--- a/Documentation/driver-api/pti_intel_mid.rst
+++ b/Documentation/driver-api/pti_intel_mid.rst
@@ -49,7 +49,9 @@ but is not just blindly executing as 'root'. Keep in mind
the use of ioctl(,TIOCSETD,) is not specific to the n_tracerouter
and n_tracesink line discpline drivers but is a generic
operation for a program to use a line discpline driver
-on a tty port other than the default n_tty::
+on a tty port other than the default n_tty:
+
+.. code-block:: c
/////////// To hook up n_tracerouter and n_tracesink /////////