summaryrefslogtreecommitdiff
path: root/Documentation/ABI/testing/sysfs-devices-sun
diff options
context:
space:
mode:
authorYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>2012-11-16 05:56:59 +0400
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2012-11-16 05:56:59 +0400
commitbb74ac23b10820d8722c3e1f4add9ef59e703f63 (patch)
tree14b9d4af4c2bfcad532d40b936392e444d100462 /Documentation/ABI/testing/sysfs-devices-sun
parent61d8eff14417fb6d6c5d57e4f0f7925e9e99fce3 (diff)
downloadlinux-bb74ac23b10820d8722c3e1f4add9ef59e703f63.tar.xz
ACPI: create _SUN sysfs file
_SUN method provides the slot unique-ID in the ACPI namespace. And The value is written in Advanced Configuration and Power Interface Specification as follows: "The _SUN value is required to be unique among the slots ofthe same type. It is also recommended that this number match the slot number printed on the physical slot whenever possible." So if we can know the value, we can identify the physical position of the slot in the system. The patch creates "sun" file in sysfs for identifying physical position of the slot. Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Reviewed-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/ABI/testing/sysfs-devices-sun')
-rw-r--r--Documentation/ABI/testing/sysfs-devices-sun14
1 files changed, 14 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-sun b/Documentation/ABI/testing/sysfs-devices-sun
new file mode 100644
index 000000000000..86be9848a77e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-sun
@@ -0,0 +1,14 @@
+Whatt: /sys/devices/.../sun
+Date: October 2012
+Contact: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
+Description:
+ The file contains a Slot-unique ID which provided by the _SUN
+ method in the ACPI namespace. The value is written in Advanced
+ Configuration and Power Interface Specification as follows:
+
+ "The _SUN value is required to be unique among the slots of
+ the same type. It is also recommended that this number match
+ the slot number printed on the physical slot whenever possible."
+
+ So reading the sysfs file, we can identify a physical position
+ of the slot in the system.