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-rw-r--r--Documentation/ABI/obsolete/sysfs-driver-hid-roccat-koneplus10
-rw-r--r--Documentation/ABI/removed/o2cb (renamed from Documentation/ABI/obsolete/o2cb)9
-rw-r--r--Documentation/ABI/testing/sysfs-block64
-rw-r--r--Documentation/ABI/testing/sysfs-bus-bcma31
-rw-r--r--Documentation/ABI/testing/sysfs-bus-pci9
-rw-r--r--Documentation/ABI/testing/sysfs-class-backlight-driver-adp887056
-rw-r--r--Documentation/ABI/testing/sysfs-devices-system-cpu34
-rw-r--r--Documentation/ABI/testing/sysfs-driver-hid-roccat-koneplus19
-rw-r--r--Documentation/ABI/testing/sysfs-firmware-dmi18
-rw-r--r--Documentation/ABI/testing/sysfs-firmware-gsmi58
-rw-r--r--Documentation/ABI/testing/sysfs-firmware-log7
-rw-r--r--Documentation/ABI/testing/sysfs-kernel-fscaps8
-rw-r--r--Documentation/ABI/testing/sysfs-kernel-mm-cleancache11
-rw-r--r--Documentation/ABI/testing/sysfs-power14
-rw-r--r--Documentation/ABI/testing/sysfs-ptp98
15 files changed, 402 insertions, 44 deletions
diff --git a/Documentation/ABI/obsolete/sysfs-driver-hid-roccat-koneplus b/Documentation/ABI/obsolete/sysfs-driver-hid-roccat-koneplus
new file mode 100644
index 000000000000..c2a270b45b03
--- /dev/null
+++ b/Documentation/ABI/obsolete/sysfs-driver-hid-roccat-koneplus
@@ -0,0 +1,10 @@
+What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/koneplus/roccatkoneplus<minor>/startup_profile
+Date: October 2010
+Contact: Stefan Achatz <erazor_de@users.sourceforge.net>
+Description: The integer value of this attribute ranges from 0-4.
+ When read, this attribute returns the number of the actual
+ profile. This value is persistent, so its equivalent to the
+ profile that's active when the mouse is powered on next time.
+ When written, this file sets the number of the startup profile
+ and the mouse activates this profile immediately.
+ Please use actual_profile, it does the same thing.
diff --git a/Documentation/ABI/obsolete/o2cb b/Documentation/ABI/removed/o2cb
index 9c49d8e6c0cc..7f5daa465093 100644
--- a/Documentation/ABI/obsolete/o2cb
+++ b/Documentation/ABI/removed/o2cb
@@ -1,11 +1,10 @@
What: /sys/o2cb symlink
-Date: Dec 2005
-KernelVersion: 2.6.16
+Date: May 2011
+KernelVersion: 2.6.40
Contact: ocfs2-devel@oss.oracle.com
-Description: This is a symlink: /sys/o2cb to /sys/fs/o2cb. The symlink will
- be removed when new versions of ocfs2-tools which know to look
+Description: This is a symlink: /sys/o2cb to /sys/fs/o2cb. The symlink is
+ removed when new versions of ocfs2-tools which know to look
in /sys/fs/o2cb are sufficiently prevalent. Don't code new
software to look here, it should try /sys/fs/o2cb instead.
- See Documentation/ABI/stable/o2cb for more information on usage.
Users: ocfs2-tools. It's sufficient to mail proposed changes to
ocfs2-devel@oss.oracle.com.
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index 4873c759d535..c1eb41cb9876 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -142,3 +142,67 @@ Description:
with the previous I/O request are enabled. When set to 2,
all merge tries are disabled. The default value is 0 -
which enables all types of merge tries.
+
+What: /sys/block/<disk>/discard_alignment
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may
+ internally allocate space in units that are bigger than
+ the exported logical block size. The discard_alignment
+ parameter indicates how many bytes the beginning of the
+ device is offset from the internal allocation unit's
+ natural alignment.
+
+What: /sys/block/<disk>/<partition>/discard_alignment
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may
+ internally allocate space in units that are bigger than
+ the exported logical block size. The discard_alignment
+ parameter indicates how many bytes the beginning of the
+ partition is offset from the internal allocation unit's
+ natural alignment.
+
+What: /sys/block/<disk>/queue/discard_granularity
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may
+ internally allocate space using units that are bigger
+ than the logical block size. The discard_granularity
+ parameter indicates the size of the internal allocation
+ unit in bytes if reported by the device. Otherwise the
+ discard_granularity will be set to match the device's
+ physical block size. A discard_granularity of 0 means
+ that the device does not support discard functionality.
+
+What: /sys/block/<disk>/queue/discard_max_bytes
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may have
+ internal limits on the number of bytes that can be
+ trimmed or unmapped in a single operation. Some storage
+ protocols also have inherent limits on the number of
+ blocks that can be described in a single command. The
+ discard_max_bytes parameter is set by the device driver
+ to the maximum number of bytes that can be discarded in
+ a single operation. Discard requests issued to the
+ device must not exceed this limit. A discard_max_bytes
+ value of 0 means that the device does not support
+ discard functionality.
+
+What: /sys/block/<disk>/queue/discard_zeroes_data
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may return
+ stale or random data when a previously discarded block
+ is read back. This can cause problems if the filesystem
+ expects discarded blocks to be explicitly cleared. If a
+ device reports that it deterministically returns zeroes
+ when a discarded area is read the discard_zeroes_data
+ parameter will be set to one. Otherwise it will be 0 and
+ the result of reading a discarded area is undefined.
diff --git a/Documentation/ABI/testing/sysfs-bus-bcma b/Documentation/ABI/testing/sysfs-bus-bcma
new file mode 100644
index 000000000000..06b62badddd1
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-bcma
@@ -0,0 +1,31 @@
+What: /sys/bus/bcma/devices/.../manuf
+Date: May 2011
+KernelVersion: 2.6.40
+Contact: Rafał Miłecki <zajec5@gmail.com>
+Description:
+ Each BCMA core has it's manufacturer id. See
+ include/linux/bcma/bcma.h for possible values.
+
+What: /sys/bus/bcma/devices/.../id
+Date: May 2011
+KernelVersion: 2.6.40
+Contact: Rafał Miłecki <zajec5@gmail.com>
+Description:
+ There are a few types of BCMA cores, they can be identified by
+ id field.
+
+What: /sys/bus/bcma/devices/.../rev
+Date: May 2011
+KernelVersion: 2.6.40
+Contact: Rafał Miłecki <zajec5@gmail.com>
+Description:
+ BCMA cores of the same type can still slightly differ depending
+ on their revision. Use it for detailed programming.
+
+What: /sys/bus/bcma/devices/.../class
+Date: May 2011
+KernelVersion: 2.6.40
+Contact: Rafał Miłecki <zajec5@gmail.com>
+Description:
+ Each BCMA core is identified by few fields, including class it
+ belongs to. See include/linux/bcma/bcma.h for possible values.
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 36bf454ba855..349ecf26ce10 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -74,6 +74,15 @@ Description:
hot-remove the PCI device and any of its children.
Depends on CONFIG_HOTPLUG.
+What: /sys/bus/pci/devices/.../pci_bus/.../rescan
+Date: May 2011
+Contact: Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+ Writing a non-zero value to this attribute will
+ force a rescan of the bus and all child buses,
+ and re-discover devices removed earlier from this
+ part of the device tree. Depends on CONFIG_HOTPLUG.
+
What: /sys/bus/pci/devices/.../rescan
Date: January 2009
Contact: Linux PCI developers <linux-pci@vger.kernel.org>
diff --git a/Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870 b/Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870
new file mode 100644
index 000000000000..aa11dbdd794b
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870
@@ -0,0 +1,56 @@
+What: /sys/class/backlight/<backlight>/<ambient light zone>_max
+What: /sys/class/backlight/<backlight>/l1_daylight_max
+What: /sys/class/backlight/<backlight>/l2_bright_max
+What: /sys/class/backlight/<backlight>/l3_office_max
+What: /sys/class/backlight/<backlight>/l4_indoor_max
+What: /sys/class/backlight/<backlight>/l5_dark_max
+Date: Mai 2011
+KernelVersion: 2.6.40
+Contact: device-drivers-devel@blackfin.uclinux.org
+Description:
+ Control the maximum brightness for <ambient light zone>
+ on this <backlight>. Values are between 0 and 127. This file
+ will also show the brightness level stored for this
+ <ambient light zone>.
+
+What: /sys/class/backlight/<backlight>/<ambient light zone>_dim
+What: /sys/class/backlight/<backlight>/l2_bright_dim
+What: /sys/class/backlight/<backlight>/l3_office_dim
+What: /sys/class/backlight/<backlight>/l4_indoor_dim
+What: /sys/class/backlight/<backlight>/l5_dark_dim
+Date: Mai 2011
+KernelVersion: 2.6.40
+Contact: device-drivers-devel@blackfin.uclinux.org
+Description:
+ Control the dim brightness for <ambient light zone>
+ on this <backlight>. Values are between 0 and 127, typically
+ set to 0. Full off when the backlight is disabled.
+ This file will also show the dim brightness level stored for
+ this <ambient light zone>.
+
+What: /sys/class/backlight/<backlight>/ambient_light_level
+Date: Mai 2011
+KernelVersion: 2.6.40
+Contact: device-drivers-devel@blackfin.uclinux.org
+Description:
+ Get conversion value of the light sensor.
+ This value is updated every 80 ms (when the light sensor
+ is enabled). Returns integer between 0 (dark) and
+ 8000 (max ambient brightness)
+
+What: /sys/class/backlight/<backlight>/ambient_light_zone
+Date: Mai 2011
+KernelVersion: 2.6.40
+Contact: device-drivers-devel@blackfin.uclinux.org
+Description:
+ Get/Set current ambient light zone. Reading returns
+ integer between 1..5 (1 = daylight, 2 = bright, ..., 5 = dark).
+ Writing a value between 1..5 forces the backlight controller
+ to enter the corresponding ambient light zone.
+ Writing 0 returns to normal/automatic ambient light level
+ operation. The ambient light sensing feature on these devices
+ is an extension to the API documented in
+ Documentation/ABI/stable/sysfs-class-backlight.
+ It can be enabled by writing the value stored in
+ /sys/class/backlight/<backlight>/max_brightness to
+ /sys/class/backlight/<backlight>/brightness. \ No newline at end of file
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 7564e88bfa43..e7be75b96e4b 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -183,21 +183,21 @@ Description: Discover and change clock speed of CPUs
to learn how to control the knobs.
-What: /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
-Date: August 2008
+What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1}
+Date: August 2008
KernelVersion: 2.6.27
-Contact: mark.langsdorf@amd.com
-Description: These files exist in every cpu's cache index directories.
- There are currently 2 cache_disable_# files in each
- directory. Reading from these files on a supported
- processor will return that cache disable index value
- for that processor and node. Writing to one of these
- files will cause the specificed cache index to be disabled.
-
- Currently, only AMD Family 10h Processors support cache index
- disable, and only for their L3 caches. See the BIOS and
- Kernel Developer's Guide at
- http://support.amd.com/us/Embedded_TechDocs/31116-Public-GH-BKDG_3-28_5-28-09.pdf
- for formatting information and other details on the
- cache index disable.
-Users: joachim.deguara@amd.com
+Contact: discuss@x86-64.org
+Description: Disable L3 cache indices
+
+ These files exist in every CPU's cache/index3 directory. Each
+ cache_disable_{0,1} file corresponds to one disable slot which
+ can be used to disable a cache index. Reading from these files
+ on a processor with this functionality will return the currently
+ disabled index for that node. There is one L3 structure per
+ node, or per internal node on MCM machines. Writing a valid
+ index to one of these files will cause the specificed cache
+ index to be disabled.
+
+ All AMD processors with L3 caches provide this functionality.
+ For details, see BKDGs at
+ http://developer.amd.com/documentation/guides/Pages/default.aspx
diff --git a/Documentation/ABI/testing/sysfs-driver-hid-roccat-koneplus b/Documentation/ABI/testing/sysfs-driver-hid-roccat-koneplus
index 326e05452da7..c1b53b8bc2ae 100644
--- a/Documentation/ABI/testing/sysfs-driver-hid-roccat-koneplus
+++ b/Documentation/ABI/testing/sysfs-driver-hid-roccat-koneplus
@@ -1,9 +1,12 @@
What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/koneplus/roccatkoneplus<minor>/actual_profile
Date: October 2010
Contact: Stefan Achatz <erazor_de@users.sourceforge.net>
-Description: When read, this file returns the number of the actual profile in
- range 0-4.
- This file is readonly.
+Description: The integer value of this attribute ranges from 0-4.
+ When read, this attribute returns the number of the actual
+ profile. This value is persistent, so its equivalent to the
+ profile that's active when the mouse is powered on next time.
+ When written, this file sets the number of the startup profile
+ and the mouse activates this profile immediately.
Users: http://roccat.sourceforge.net
What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/koneplus/roccatkoneplus<minor>/firmware_version
@@ -89,16 +92,6 @@ Description: The mouse has a tracking- and a distance-control-unit. These
This file is writeonly.
Users: http://roccat.sourceforge.net
-What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/koneplus/roccatkoneplus<minor>/startup_profile
-Date: October 2010
-Contact: Stefan Achatz <erazor_de@users.sourceforge.net>
-Description: The integer value of this attribute ranges from 0-4.
- When read, this attribute returns the number of the profile
- that's active when the mouse is powered on.
- When written, this file sets the number of the startup profile
- and the mouse activates this profile immediately.
-Users: http://roccat.sourceforge.net
-
What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/koneplus/roccatkoneplus<minor>/tcu
Date: October 2010
Contact: Stefan Achatz <erazor_de@users.sourceforge.net>
diff --git a/Documentation/ABI/testing/sysfs-firmware-dmi b/Documentation/ABI/testing/sysfs-firmware-dmi
index ba9da9503c23..c78f9ab01e56 100644
--- a/Documentation/ABI/testing/sysfs-firmware-dmi
+++ b/Documentation/ABI/testing/sysfs-firmware-dmi
@@ -14,14 +14,15 @@ Description:
DMI is structured as a large table of entries, where
each entry has a common header indicating the type and
- length of the entry, as well as 'handle' that is
- supposed to be unique amongst all entries.
+ length of the entry, as well as a firmware-provided
+ 'handle' that is supposed to be unique amongst all
+ entries.
Some entries are required by the specification, but many
others are optional. In general though, users should
never expect to find a specific entry type on their
system unless they know for certain what their firmware
- is doing. Machine to machine will vary.
+ is doing. Machine to machine experiences will vary.
Multiple entries of the same type are allowed. In order
to handle these duplicate entry types, each entry is
@@ -67,25 +68,24 @@ Description:
and the two terminating nul characters.
type : The type of the entry. This value is the same
as found in the directory name. It indicates
- how the rest of the entry should be
- interpreted.
+ how the rest of the entry should be interpreted.
instance: The instance ordinal of the entry for the
given type. This value is the same as found
in the parent directory name.
- position: The position of the entry within the entirety
- of the entirety.
+ position: The ordinal position (zero-based) of the entry
+ within the entirety of the DMI entry table.
=== Entry Specialization ===
Some entry types may have other information available in
- sysfs.
+ sysfs. Not all types are specialized.
--- Type 15 - System Event Log ---
This entry allows the firmware to export a log of
events the system has taken. This information is
typically backed by nvram, but the implementation
- details are abstracted by this table. This entries data
+ details are abstracted by this table. This entry's data
is exported in the directory:
/sys/firmware/dmi/entries/15-0/system_event_log
diff --git a/Documentation/ABI/testing/sysfs-firmware-gsmi b/Documentation/ABI/testing/sysfs-firmware-gsmi
new file mode 100644
index 000000000000..0faa0aaf4b6a
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-gsmi
@@ -0,0 +1,58 @@
+What: /sys/firmware/gsmi
+Date: March 2011
+Contact: Mike Waychison <mikew@google.com>
+Description:
+ Some servers used internally at Google have firmware
+ that provides callback functionality via explicit SMI
+ triggers. Some of the callbacks are similar to those
+ provided by the EFI runtime services page, but due to
+ historical reasons this different entry-point has been
+ used.
+
+ The gsmi driver implements the kernel's abstraction for
+ these firmware callbacks. Currently, this functionality
+ is limited to handling the system event log and getting
+ access to EFI-style variables stored in nvram.
+
+ Layout:
+
+ /sys/firmware/gsmi/vars:
+
+ This directory has the same layout (and
+ underlying implementation as /sys/firmware/efi/vars.
+ See Documentation/ABI/*/sysfs-firmware-efi-vars
+ for more information on how to interact with
+ this structure.
+
+ /sys/firmware/gsmi/append_to_eventlog - write-only:
+
+ This file takes a binary blob and passes it onto
+ the firmware to be timestamped and appended to
+ the system eventlog. The binary format is
+ interpreted by the firmware and may change from
+ platform to platform. The only kernel-enforced
+ requirement is that the blob be prefixed with a
+ 32bit host-endian type used as part of the
+ firmware call.
+
+ /sys/firmware/gsmi/clear_config - write-only:
+
+ Writing any value to this file will cause the
+ entire firmware configuration to be reset to
+ "factory defaults". Callers should assume that
+ a reboot is required for the configuration to be
+ cleared.
+
+ /sys/firmware/gsmi/clear_eventlog - write-only:
+
+ This file is used to clear out a portion/the
+ whole of the system event log. Values written
+ should be values between 1 and 100 inclusive (in
+ ASCII) representing the fraction of the log to
+ clear. Not all platforms support fractional
+ clearing though, and this writes to this file
+ will error out if the firmware doesn't like your
+ submitted fraction.
+
+ Callers should assume that a reboot is needed
+ for this operation to complete.
diff --git a/Documentation/ABI/testing/sysfs-firmware-log b/Documentation/ABI/testing/sysfs-firmware-log
new file mode 100644
index 000000000000..9b58e7c5365f
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-log
@@ -0,0 +1,7 @@
+What: /sys/firmware/log
+Date: February 2011
+Contact: Mike Waychison <mikew@google.com>
+Description:
+ The /sys/firmware/log is a binary file that represents a
+ read-only copy of the firmware's log if one is
+ available.
diff --git a/Documentation/ABI/testing/sysfs-kernel-fscaps b/Documentation/ABI/testing/sysfs-kernel-fscaps
new file mode 100644
index 000000000000..50a3033b5e15
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-fscaps
@@ -0,0 +1,8 @@
+What: /sys/kernel/fscaps
+Date: February 2011
+KernelVersion: 2.6.38
+Contact: Ludwig Nussel <ludwig.nussel@suse.de>
+Description
+ Shows whether file system capabilities are honored
+ when executing a binary
+
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-cleancache b/Documentation/ABI/testing/sysfs-kernel-mm-cleancache
new file mode 100644
index 000000000000..662ae646ea12
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-cleancache
@@ -0,0 +1,11 @@
+What: /sys/kernel/mm/cleancache/
+Date: April 2011
+Contact: Dan Magenheimer <dan.magenheimer@oracle.com>
+Description:
+ /sys/kernel/mm/cleancache/ contains a number of files which
+ record a count of various cleancache operations
+ (sum across all filesystems):
+ succ_gets
+ failed_gets
+ puts
+ flushes
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power
index 194ca446ac28..b464d12761ba 100644
--- a/Documentation/ABI/testing/sysfs-power
+++ b/Documentation/ABI/testing/sysfs-power
@@ -158,3 +158,17 @@ Description:
successful, will make the kernel abort a subsequent transition
to a sleep state if any wakeup events are reported after the
write has returned.
+
+What: /sys/power/reserved_size
+Date: May 2011
+Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Description:
+ The /sys/power/reserved_size file allows user space to control
+ the amount of memory reserved for allocations made by device
+ drivers during the "device freeze" stage of hibernation. It can
+ be written a string representing a non-negative integer that
+ will be used as the amount of memory to reserve for allocations
+ made by device drivers' "freeze" callbacks, in bytes.
+
+ Reading from this file will display the current value, which is
+ set to 1 MB by default.
diff --git a/Documentation/ABI/testing/sysfs-ptp b/Documentation/ABI/testing/sysfs-ptp
new file mode 100644
index 000000000000..d40d2b550502
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-ptp
@@ -0,0 +1,98 @@
+What: /sys/class/ptp/
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This directory contains files and directories
+ providing a standardized interface to the ancillary
+ features of PTP hardware clocks.
+
+What: /sys/class/ptp/ptpN/
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This directory contains the attributes of the Nth PTP
+ hardware clock registered into the PTP class driver
+ subsystem.
+
+What: /sys/class/ptp/ptpN/clock_name
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This file contains the name of the PTP hardware clock
+ as a human readable string.
+
+What: /sys/class/ptp/ptpN/max_adjustment
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This file contains the PTP hardware clock's maximum
+ frequency adjustment value (a positive integer) in
+ parts per billion.
+
+What: /sys/class/ptp/ptpN/n_alarms
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This file contains the number of periodic or one shot
+ alarms offer by the PTP hardware clock.
+
+What: /sys/class/ptp/ptpN/n_external_timestamps
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This file contains the number of external timestamp
+ channels offered by the PTP hardware clock.
+
+What: /sys/class/ptp/ptpN/n_periodic_outputs
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This file contains the number of programmable periodic
+ output channels offered by the PTP hardware clock.
+
+What: /sys/class/ptp/ptpN/pps_avaiable
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This file indicates whether the PTP hardware clock
+ supports a Pulse Per Second to the host CPU. Reading
+ "1" means that the PPS is supported, while "0" means
+ not supported.
+
+What: /sys/class/ptp/ptpN/extts_enable
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This write-only file enables or disables external
+ timestamps. To enable external timestamps, write the
+ channel index followed by a "1" into the file.
+ To disable external timestamps, write the channel
+ index followed by a "0" into the file.
+
+What: /sys/class/ptp/ptpN/fifo
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This file provides timestamps on external events, in
+ the form of three integers: channel index, seconds,
+ and nanoseconds.
+
+What: /sys/class/ptp/ptpN/period
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This write-only file enables or disables periodic
+ outputs. To enable a periodic output, write five
+ integers into the file: channel index, start time
+ seconds, start time nanoseconds, period seconds, and
+ period nanoseconds. To disable a periodic output, set
+ all the seconds and nanoseconds values to zero.
+
+What: /sys/class/ptp/ptpN/pps_enable
+Date: September 2010
+Contact: Richard Cochran <richardcochran@gmail.com>
+Description:
+ This write-only file enables or disables delivery of
+ PPS events to the Linux PPS subsystem. To enable PPS
+ events, write a "1" into the file. To disable events,
+ write a "0" into the file.