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authorGuenter Roeck <linux@roeck-us.net>2016-12-28 02:28:19 +0300
committerGuenter Roeck <linux@roeck-us.net>2018-12-17 02:13:22 +0300
commita5c47c0d388b939dd578fd466aa804b7f2445390 (patch)
treea599b1995485e5907df5ebf9562c3591b6773c08 /Documentation/hwmon
parent2e9a41bbc1079776dabe42ed8113b086b99ae56c (diff)
downloadlinux-a5c47c0d388b939dd578fd466aa804b7f2445390.tar.xz
hwmon: Introduce SENSOR_DEVICE_ATTR_{RO, RW, WO} and variants
Introduce SENSOR_DEVICE_ATTR_{RO,RW,WO} and SENSOR_DEVICE_ATTR_2_{RO,RW,WO} as simplified variants of SENSOR_DEVICE_ATTR and SENSOR_DEVICE_ATTR_2 to simplify the source code, improve readbility, and reduce the chance of inconsistencies. Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'Documentation/hwmon')
-rw-r--r--Documentation/hwmon/hwmon-kernel-api.txt24
1 files changed, 16 insertions, 8 deletions
diff --git a/Documentation/hwmon/hwmon-kernel-api.txt b/Documentation/hwmon/hwmon-kernel-api.txt
index eb7a78aebb38..8bdefb41be30 100644
--- a/Documentation/hwmon/hwmon-kernel-api.txt
+++ b/Documentation/hwmon/hwmon-kernel-api.txt
@@ -299,17 +299,25 @@ functions is used.
The header file linux/hwmon-sysfs.h provides a number of useful macros to
declare and use hardware monitoring sysfs attributes.
-In many cases, you can use the exsting define DEVICE_ATTR to declare such
-attributes. This is feasible if an attribute has no additional context. However,
-in many cases there will be additional information such as a sensor index which
-will need to be passed to the sysfs attribute handling function.
+In many cases, you can use the exsting define DEVICE_ATTR or its variants
+DEVICE_ATTR_{RW,RO,WO} to declare such attributes. This is feasible if an
+attribute has no additional context. However, in many cases there will be
+additional information such as a sensor index which will need to be passed
+to the sysfs attribute handling function.
SENSOR_DEVICE_ATTR and SENSOR_DEVICE_ATTR_2 can be used to define attributes
which need such additional context information. SENSOR_DEVICE_ATTR requires
one additional argument, SENSOR_DEVICE_ATTR_2 requires two.
-SENSOR_DEVICE_ATTR defines a struct sensor_device_attribute variable.
-This structure has the following fields.
+Simplified variants of SENSOR_DEVICE_ATTR and SENSOR_DEVICE_ATTR_2 are available
+and should be used if standard attribute permissions and function names are
+feasible. Standard permissions are 0644 for SENSOR_DEVICE_ATTR[_2]_RW,
+0444 for SENSOR_DEVICE_ATTR[_2]_RO, and 0200 for SENSOR_DEVICE_ATTR[_2]_WO.
+Standard functions, similar to DEVICE_ATTR_{RW,RO,WO}, have _show and _store
+appended to the provided function name.
+
+SENSOR_DEVICE_ATTR and its variants define a struct sensor_device_attribute
+variable. This structure has the following fields.
struct sensor_device_attribute {
struct device_attribute dev_attr;
@@ -320,8 +328,8 @@ You can use to_sensor_dev_attr to get the pointer to this structure from the
attribute read or write function. Its parameter is the device to which the
attribute is attached.
-SENSOR_DEVICE_ATTR_2 defines a struct sensor_device_attribute_2 variable,
-which is defined as follows.
+SENSOR_DEVICE_ATTR_2 and its variants define a struct sensor_device_attribute_2
+variable, which is defined as follows.
struct sensor_device_attribute_2 {
struct device_attribute dev_attr;