Currently the only way to specify a hibernate offset for a
swap file is on the kernel command line.

Add a new /sys/power/resume_offset that lets userspace
specify the offset and disk to use when initiating a hibernate
cycle.
Signed-off-by: NMario Limonciello <mario.limonciello@dell.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add a new attribute group called "s2idle" under the sysfs directory
of each cpuidle state that supports the ->enter_s2idle callback
and put two new attributes, "usage" and "time", into that group to
represent the number of times the given state was requested for
suspend-to-idle and the total time spent in suspend-to-idle after
requesting that state, respectively.

That will allow diagnostic information related to suspend-to-idle
to be collected without enabling advanced debug features and
analyzing dmesg output.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Document the core of the debugfs CEC error injection ABI.

The driver specific commands are documented elsewhere and
this file points to that documentation.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

USB role switch is a device that can be used to choose the
data role for USB connector. With dual-role capable USB
controllers, the controller itself will be the switch, but
on some platforms the USB host and device controllers are
separate IPs and there is a mux between them and the
connector. On those platforms the mux driver will need to
register the switch.

With USB Type-C connectors, the host-to-device relationship
is negotiated over the Configuration Channel (CC). That
means the USB Type-C drivers need to be in control of the
role switch. The class provides a simple API for the USB
Type-C drivers for the control.

For other types of USB connectors (mainly microAB) the class
provides user space control via sysfs attribute file that
can be used to request role swapping from the switch.
Reviewed-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

For some userspace applications information on the number of
over-current conditions at specific USB hub ports is relevant.

In our case we have a series of USB hardware (using the cp210x driver)
which communicates using a proprietary protocol. These devices sometimes
trigger an over-current situation on some hubs. In case of such an
over-current situation the USB devices offer an interface for reducing
the max used power. As these conditions are quite rare and imply
performance reductions of the device we don't want to reduce the max
power always.

Therefore give user-space applications the possibility to react
adequately by introducing an over_current_counter in the usb port struct
which is exported via sysfs.
Signed-off-by: NRichard Leitner <richard.leitner@skidata.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

UFS host controllers may support an autonomous power management feature
called the Auto-Hibernate Idle Timer. The timer is set to the number of
microseconds of idle time before the UFS host controller will autonomously
put the link into Hibernate state. That will save power at the expense of
increased latency. Any access to the host controller interface registers
will automatically put the link out of Hibernate state. So once configured,
the feature is transparent to the driver.

Expose the Auto-Hibernate Idle Timer value via SysFS to allow users to
choose between power efficiency or lower latency. Set a default value of
150 ms.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Acked-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Read from these files will return the integer value of the chosen power
management level now. Separate entries were added to show the target UFS
device and UIC link states. The description of the possible power
managements levels was added to the ABI file. The on-write behaviour of
these entries wasn't changed.

[mkp: typo]
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Descriptions have been collected from git commit logs, code commits and
the TrackPoint System Version 4.0 Engineering Specification.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Descriptions have collected from code comments and by reading through
code.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

This is an attempt to document the nfit sysfs interface. The
descriptions have been collected from git commit logs and the ACPI
specification 6.2.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

The existing sysfs interface has been updated to be in the same format
as described in Documentation/ABI/README. This will be useful for
scripting and tracking changes in the ABI. Attributes have been grouped
by functionality and/or the date on which they were added.

There are a couple of more changes:
- The attributes have been annotated with file permissions RO/RW/WO.
- Added description of the bus attribute supported_features
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Introduce a driver for the ACPI Time and Alarm Device (TAD) based on
Section 9.18 of ACPI 6.2.

This driver only supports the system wakeup capabilities of the TAD
which are mandatory.  Support for the RTC capabilities of the TAD
will be added to it in the future.

This driver is entirely sysfs-based.  It provides attributes (under
the TAD platform device) to allow user space to manage the AC and DC
wakeup timers of the TAD: set and read their values, set and check
their expire timer wake policies, check and clear their status and
check the capabilities of the TAD reported by AML.  The DC timer
attributes are only present if the TAD supports a separate DC alarm
timer.

The wakeup events handling and power management of the TAD is
expected to be taken care of by the ACPI PM domain attached to its
platform device.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

Limit the number of queued writes per client.
Writes above this threshold are blocked till place
in the transmit queue is available.
The limit is configurable via sysfs and defaults to 50.
The implementation should provide blocking I/O behavior.
Prior to this change one would end up in the hands of OOM.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This change introduces an 'external mode' for GPIO-based FSI masters,
allowing the clock and data lines to be driven by an external source.
For example, external mode is selected by a user when an external debug
device is attached to the FSI pins.

To do this, we need to set specific states for the trans, mux and enable
GPIOs, and prevent access to clk & data from the FSI core code (by
returning EBUSY).

External mode is controlled by a sysfs attribute, so add the relevant
information to Documentation/ABI/
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Reviewed-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This new security level works so that it creates one PCIe tunnel to the
connected Thunderbolt dock, removing PCIe links downstream of the dock.
This leaves only the internal USB controller visible.

Display Port tunnels are created normally.

While there make sure security sysfs attribute returns "unknown" for any
future security level.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>

Preboot ACL is a mechanism that allows connecting Thunderbolt devices
boot time in more secure way than the legacy Thunderbolt boot support.
As with the legacy boot option, this also needs to be enabled from the
BIOS before booting is allowed. Difference to the legacy mode is that
the userspace software explicitly adds device UUIDs by sending a special
message to the ICM firmware. Only the devices listed in the boot ACL are
connected automatically during the boot. This works in both "user" and
"secure" security levels.

We implement this in Linux by exposing a new sysfs attribute (boot_acl)
below each Thunderbolt domain. The userspace software can then update
the full list as needed.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>

In various cases, Thunderbolt device can be connected by ICM on boot
without waiting for approval from user. Most cases are related to
OEM-specific BIOS configurations. This information is interesting for
user-space as if the device isn't in SW ACL, it may create a friction in
the user experience where the device is automatically authorized if it's
connected on boot but requires an explicit user action if connected
after OS is up. User-space can use this information to suggest adding
the device to SW ACL for auto-authorization on later connections.
Signed-off-by: NYehezkel Bernat <yehezkel.bernat@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>

Add sysfs documentation for N-Trig touchscreens under Documentation/ABI.
Descriptions have been collected from code comments.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Descriptions have been collected from git commit logs.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Surprisingly there is no simple way to see if the IRQ line in question
is wakeup source or not.

Note that wakeup might be an OOB (out-of-band) source like GPIO line
which makes things slightly more complicated.

Add a sysfs node to cover this case.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NTony Lindgren <tony@atomide.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20180226155043.67937-1-andriy.shevchenko@linux.intel.com

This is an attempt to document the sysfs interface for the IPMI drivers.
Descriptions were collected from v2.0 of the IPMI specification and from
code comments.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NCorey Minyard <cminyard@mvista.com>

Right now, the description of the rapidio sysfs interfaces is in
Documentation/rapidio/sysfs.txt. Since these are a part of the ABI, they
should be in Documentation/ABI along with the rest.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Acked-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Add documentation for sysfs interface of adp8860 series backlight
devices by reading through code and git commits.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Acked-by: NMichael Hennerich <michael.hennerich@analog.com>
Acked-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Add documentation for sysfs interface of adp5520/adp5501 analog devices
backlight driver by reading code and looking through git commit logs.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Acked-by: NMichael Hennerich <michael.hennerich@analog.com>
Acked-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Add documentation for sysfs interfaces of Texas Instruments lm3639
backlight + flash led driver chip by looking through git commits and
reading code.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Acked-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Documentation has been compiled from git logs and by reading through
code.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Add documentation for core and hardware specific infiniband interfaces.
The descriptions have been collected from git commit logs, reading
through code and data sheets. Some drivers have incomplete doc and are
annotated with the comment '[to be documented]'.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Reviewed-by: NHal Rosenstock <hal@mellanox.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Documentation has been compiled from git commit logs and descriptions in
Documentation/aoe/aoe.txt. This should be useful for scripting and
tracking changes in the ABI.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Document sysfs attributes of s6e63m0 lcd panel driver by looking through
git logs and reading code.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Clean up the sysfs documentation such that it is in the same format as
described in Documentation/ABI/README. Mainly, the patch moves the
attribute names to the 'What:' field. This might be useful for scripting
and tracking changes in the ABI.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Add documentation for two attributes, status and hrv, in
Documentation/ABI/testing/sysfs-bus-acpi.

Compiled from git logs and the ACPI specification.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
[ rjw: Minor changes ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Change email contact for ABI documention to author's current employer
on the following files:

* sysfs-bus-iio-chemical-vz89x
* sysfs-bus-iio-proximity-as3935
Signed-off-by: NMatt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>

This patch introduces a sysfs group entry for the UFS attributes. The
group adds "attributes" folder under the UFS driver sysfs entry
(/sys/bus/platform/drivers/ufshcd/*). The attributes are shown
as hexadecimal numbers. The full information about the attributes could
be found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch introduces a sysfs group entry for the UFS flags. The group adds
"flags" folder under the UFS driver sysfs entry
(/sys/bus/platform/drivers/ufshcd/*). The flags are shown as boolean value
("true" or "false"). The full information about the UFS flags could be
found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch introduces a sysfs group entry for the UFS unit descriptor
parameters. The group adds "unit_descriptor" folder under the corresponding
SCSI device sysfs entry (/sys/class/scsi_device/*/device/). The parameters
are shown as hexadecimal numbers. The full information about the parameters
could be found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch introduces a sysfs group entry for the UFS string descriptors.
The group adds "string_descriptors" folder under the UFS driver
sysfs entry (/sys/bus/platform/drivers/ufshcd/*). The folder will contain
5 files that will show string values defined by the UFS spec:
a manufacturer name, a product name, an OEM id, a serial number and a
product revision.  The full information about the string descriptors
could be found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch introduces a sysfs group entry for the UFS power descriptor
parameters. The group adds "power_descriptor" folder under the UFS driver
sysfs entry (/sys/bus/platform/drivers/ufshcd/*). The parameters are shown
as hexadecimal numbers. The full information about the parameters could be
found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch introduces a sysfs group entry for the UFS health descriptor
parameters. The group adds "health_descriptor" folder under the UFS driver
sysfs entry (/sys/bus/platform/drivers/ufshcd/*). The parameters are shown
as hexadecimal numbers. The full information about the parameters could be
found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch introduces a sysfs group entry for the UFS geometry descriptor
parameters. The group adds "geometry_descriptor" folder under the UFS
driver sysfs entry (/sys/bus/platform/drivers/ufshcd/*). The parameters
are shown as hexadecimal numbers. The full information about the parameters
could be found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch introduces a sysfs group entry for the UFS interconnect
descriptor parameters. The group adds "interconnect_descriptor" folder
under the UFS driver sysfs entry (/sys/bus/platform/drivers/ufshcd/*).
The parameters are shown as hexadecimal numbers. The full information
about the parameters could be found at UFS specifications 2.1.
Signed-off-by: NStanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>