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authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-05 15:59:24 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-05 15:59:24 -0800
commit5ebe0ee802c52cdf0c0eed8f3eccc9a056e412a3 (patch)
tree0eb28b0315a44593404f58b9758d31e0afc41425 /Documentation/gpio
parent1873499e13648a2dd01a394ed3217c9290921b3d (diff)
parent3ce96239d482a7d2dfdc1f332152c580b219fef1 (diff)
downloadlinux-5ebe0ee802c52cdf0c0eed8f3eccc9a056e412a3.tar.bz2
Merge tag 'docs-for-linus' of git://git.lwn.net/linux
Pull documentation update from Jon Corbet: "There is a nice new document from Neil on how pathname lookups work and some new CAN driver documentation. Beyond that, we have kernel-doc fixes, a bit more work to support reproducible builds, and the usual collection of small fixes" * tag 'docs-for-linus' of git://git.lwn.net/linux: (34 commits) Documentation: add new description of path-name lookup. Documentation/vm/slub.txt: document slabinfo-gnuplot.sh Doc: ABI/stable: Fix typo in ABI/stable doc: Clarify that nmi_watchdog param is for hardlockups Typo correction for description in gpio document. DocBook: Fix kernel-doc to be case-insensitive for private: kernel-docs.txt: update kernelnewbies reference Doc:kvm: Fix typo in Doc/virtual/kvm Documentation/Changes: Add bc in "Current Minimal Requirements" section Documentation/email-clients.txt: remove trailing whitespace DocBook: Use a fixed encoding for output MAINTAINERS: The docs tree has moved Docs/kernel-parameters: Add earlycon devicetree usage SubmittingPatches: make Subject examples match the de facto standard Documentation: gpio: mention that <function>-gpio has been deprecated Documentation: cgroups: just fix a few typos Documentation: Update kselftest.txt Documentation: DMA API: Be more explicit that nents is always the same Documentation: Update the default value of crashkernel low zram: update documentation ...
Diffstat (limited to 'Documentation/gpio')
-rw-r--r--Documentation/gpio/board.txt10
-rw-r--r--Documentation/gpio/sysfs.txt6
2 files changed, 10 insertions, 6 deletions
diff --git a/Documentation/gpio/board.txt b/Documentation/gpio/board.txt
index f59c43b6411b..3092178628c4 100644
--- a/Documentation/gpio/board.txt
+++ b/Documentation/gpio/board.txt
@@ -21,8 +21,8 @@ exact way to do it depends on the GPIO controller providing the GPIOs, see the
device tree bindings for your controller.
GPIOs mappings are defined in the consumer device's node, in a property named
-either <function>-gpios or <function>-gpio, where <function> is the function
-the driver will request through gpiod_get(). For example:
+<function>-gpios, where <function> is the function the driver will request
+through gpiod_get(). For example:
foo_device {
compatible = "acme,foo";
@@ -31,9 +31,13 @@ the driver will request through gpiod_get(). For example:
<&gpio 16 GPIO_ACTIVE_HIGH>, /* green */
<&gpio 17 GPIO_ACTIVE_HIGH>; /* blue */
- power-gpio = <&gpio 1 GPIO_ACTIVE_LOW>;
+ power-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
};
+Properties named <function>-gpio are also considered valid and old bindings use
+it but are only supported for compatibility reasons and should not be used for
+newer bindings since it has been deprecated.
+
This property will make GPIOs 15, 16 and 17 available to the driver under the
"led" function, and GPIO 1 as the "power" GPIO:
diff --git a/Documentation/gpio/sysfs.txt b/Documentation/gpio/sysfs.txt
index 0700b55637f5..aeab01aa4d00 100644
--- a/Documentation/gpio/sysfs.txt
+++ b/Documentation/gpio/sysfs.txt
@@ -20,14 +20,14 @@ userspace GPIO can be used to determine system configuration data that
standard kernels won't know about. And for some tasks, simple userspace
GPIO drivers could be all that the system really needs.
-DO NOT ABUSE SYFS TO CONTROL HARDWARE THAT HAS PROPER KERNEL DRIVERS.
+DO NOT ABUSE SYSFS TO CONTROL HARDWARE THAT HAS PROPER KERNEL DRIVERS.
PLEASE READ THE DOCUMENT NAMED "drivers-on-gpio.txt" IN THIS DOCUMENTATION
DIRECTORY TO AVOID REINVENTING KERNEL WHEELS IN USERSPACE. I MEAN IT.
REALLY.
Paths in Sysfs
--------------
-There are three kinds of entry in /sys/class/gpio:
+There are three kinds of entries in /sys/class/gpio:
- Control interfaces used to get userspace control over GPIOs;
@@ -106,7 +106,7 @@ read-only attributes:
"label" ... provided for diagnostics (not always unique)
- "ngpio" ... how many GPIOs this manges (N to N + ngpio - 1)
+ "ngpio" ... how many GPIOs this manages (N to N + ngpio - 1)
Board documentation should in most cases cover what GPIOs are used for
what purposes. However, those numbers are not always stable; GPIOs on