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-rw-r--r--Documentation/ABI/stable/sysfs-bus-w12
-rw-r--r--Documentation/ABI/stable/sysfs-driver-w1_ds28e044
-rw-r--r--Documentation/ABI/stable/sysfs-driver-w1_ds28ea002
-rw-r--r--Documentation/ABI/testing/debugfs-hisi-zip50
-rw-r--r--Documentation/ABI/testing/debugfs-moxtet23
-rw-r--r--Documentation/ABI/testing/dev-kmsg15
-rw-r--r--Documentation/ABI/testing/ima_policy6
-rw-r--r--Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm322
-rw-r--r--Documentation/ABI/testing/sysfs-bus-iio-timer-stm3223
-rw-r--r--Documentation/ABI/testing/sysfs-bus-intel_th-devices-msc3
-rw-r--r--Documentation/ABI/testing/sysfs-bus-moxtet-devices17
-rw-r--r--Documentation/ABI/testing/sysfs-class-backlight26
-rw-r--r--Documentation/ABI/testing/sysfs-class-mic (renamed from Documentation/ABI/testing/sysfs-class-mic.txt)0
-rw-r--r--Documentation/ABI/testing/sysfs-class-remoteproc10
-rw-r--r--Documentation/ABI/testing/sysfs-class-wakeup76
-rw-r--r--Documentation/ABI/testing/sysfs-class-watchdog34
-rw-r--r--Documentation/ABI/testing/sysfs-devices-platform-stratix10-rsu128
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power9
-rw-r--r--Documentation/ABI/testing/sysfs-devices-soc7
-rw-r--r--Documentation/ABI/testing/sysfs-devices-system-cpu10
-rw-r--r--Documentation/ABI/testing/sysfs-driver-habanalabs14
-rw-r--r--Documentation/ABI/testing/sysfs-firmware-efi8
-rw-r--r--Documentation/ABI/testing/sysfs-firmware-turris-mox-rwtm37
-rw-r--r--Documentation/ABI/testing/sysfs-fs-f2fs7
-rw-r--r--Documentation/ABI/testing/sysfs-kernel-btf17
-rw-r--r--Documentation/ABI/testing/sysfs-kernel-slab13
-rw-r--r--Documentation/ABI/testing/sysfs-platform-dfl-fme85
-rw-r--r--Documentation/ABI/testing/sysfs-platform-dfl-port85
-rw-r--r--Documentation/ABI/testing/sysfs-power106
29 files changed, 767 insertions, 52 deletions
diff --git a/Documentation/ABI/stable/sysfs-bus-w1 b/Documentation/ABI/stable/sysfs-bus-w1
index 140d85b4ae92..992dfb183ed0 100644
--- a/Documentation/ABI/stable/sysfs-bus-w1
+++ b/Documentation/ABI/stable/sysfs-bus-w1
@@ -6,6 +6,6 @@ Description: Bus scanning interval, microseconds component.
control systems are attached/generate presence for as short as
100 ms - hence the tens-to-hundreds milliseconds scan intervals
are required.
- see Documentation/w1/w1.generic for detailed information.
+ see Documentation/w1/w1-generic.rst for detailed information.
Users: any user space application which wants to know bus scanning
interval
diff --git a/Documentation/ABI/stable/sysfs-driver-w1_ds28e04 b/Documentation/ABI/stable/sysfs-driver-w1_ds28e04
index 26579ee868c9..3e1c1fa8d54d 100644
--- a/Documentation/ABI/stable/sysfs-driver-w1_ds28e04
+++ b/Documentation/ABI/stable/sysfs-driver-w1_ds28e04
@@ -2,7 +2,7 @@ What: /sys/bus/w1/devices/.../pio
Date: May 2012
Contact: Markus Franke <franm@hrz.tu-chemnitz.de>
Description: read/write the contents of the two PIO's of the DS28E04-100
- see Documentation/w1/slaves/w1_ds28e04 for detailed information
+ see Documentation/w1/slaves/w1_ds28e04.rst for detailed information
Users: any user space application which wants to communicate with DS28E04-100
@@ -11,5 +11,5 @@ What: /sys/bus/w1/devices/.../eeprom
Date: May 2012
Contact: Markus Franke <franm@hrz.tu-chemnitz.de>
Description: read/write the contents of the EEPROM memory of the DS28E04-100
- see Documentation/w1/slaves/w1_ds28e04 for detailed information
+ see Documentation/w1/slaves/w1_ds28e04.rst for detailed information
Users: any user space application which wants to communicate with DS28E04-100
diff --git a/Documentation/ABI/stable/sysfs-driver-w1_ds28ea00 b/Documentation/ABI/stable/sysfs-driver-w1_ds28ea00
index e928def14f28..534e63731a49 100644
--- a/Documentation/ABI/stable/sysfs-driver-w1_ds28ea00
+++ b/Documentation/ABI/stable/sysfs-driver-w1_ds28ea00
@@ -2,5 +2,5 @@ What: /sys/bus/w1/devices/.../w1_seq
Date: Apr 2015
Contact: Matt Campbell <mattrcampbell@gmail.com>
Description: Support for the DS28EA00 chain sequence function
- see Documentation/w1/slaves/w1_therm for detailed information
+ see Documentation/w1/slaves/w1_therm.rst for detailed information
Users: any user space application which wants to communicate with DS28EA00
diff --git a/Documentation/ABI/testing/debugfs-hisi-zip b/Documentation/ABI/testing/debugfs-hisi-zip
new file mode 100644
index 000000000000..a7c63e6c4bc3
--- /dev/null
+++ b/Documentation/ABI/testing/debugfs-hisi-zip
@@ -0,0 +1,50 @@
+What: /sys/kernel/debug/hisi_zip/<bdf>/comp_core[01]/regs
+Date: Nov 2018
+Contact: linux-crypto@vger.kernel.org
+Description: Dump of compression cores related debug registers.
+ Only available for PF.
+
+What: /sys/kernel/debug/hisi_zip/<bdf>/decomp_core[0-5]/regs
+Date: Nov 2018
+Contact: linux-crypto@vger.kernel.org
+Description: Dump of decompression cores related debug registers.
+ Only available for PF.
+
+What: /sys/kernel/debug/hisi_zip/<bdf>/clear_enable
+Date: Nov 2018
+Contact: linux-crypto@vger.kernel.org
+Description: Compression/decompression core debug registers read clear
+ control. 1 means enable register read clear, otherwise 0.
+ Writing to this file has no functional effect, only enable or
+ disable counters clear after reading of these registers.
+ Only available for PF.
+
+What: /sys/kernel/debug/hisi_zip/<bdf>/current_qm
+Date: Nov 2018
+Contact: linux-crypto@vger.kernel.org
+Description: One ZIP controller has one PF and multiple VFs, each function
+ has a QM. Select the QM which below qm refers to.
+ Only available for PF.
+
+What: /sys/kernel/debug/hisi_zip/<bdf>/qm/qm_regs
+Date: Nov 2018
+Contact: linux-crypto@vger.kernel.org
+Description: Dump of QM related debug registers.
+ Available for PF and VF in host. VF in guest currently only
+ has one debug register.
+
+What: /sys/kernel/debug/hisi_zip/<bdf>/qm/current_q
+Date: Nov 2018
+Contact: linux-crypto@vger.kernel.org
+Description: One QM may contain multiple queues. Select specific queue to
+ show its debug registers in above qm_regs.
+ Only available for PF.
+
+What: /sys/kernel/debug/hisi_zip/<bdf>/qm/clear_enable
+Date: Nov 2018
+Contact: linux-crypto@vger.kernel.org
+Description: QM debug registers(qm_regs) read clear control. 1 means enable
+ register read clear, otherwise 0.
+ Writing to this file has no functional effect, only enable or
+ disable counters clear after reading of these registers.
+ Only available for PF.
diff --git a/Documentation/ABI/testing/debugfs-moxtet b/Documentation/ABI/testing/debugfs-moxtet
new file mode 100644
index 000000000000..67b1717794d8
--- /dev/null
+++ b/Documentation/ABI/testing/debugfs-moxtet
@@ -0,0 +1,23 @@
+What: /sys/kernel/debug/moxtet/input
+Date: March 2019
+KernelVersion: 5.3
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) Read input from the shift registers, in hexadecimal.
+ Returns N+1 bytes, where N is the number of Moxtet connected
+ modules. The first byte is from the CPU board itself.
+ Example: 101214
+ 10: CPU board with SD card
+ 12: 2 = PCIe module, 1 = IRQ not active
+ 14: 4 = Peridot module, 1 = IRQ not active
+
+What: /sys/kernel/debug/moxtet/output
+Date: March 2019
+KernelVersion: 5.3
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (RW) Read last written value to the shift registers, in
+ hexadecimal, or write values to the shift registers, also
+ in hexadecimal.
+ Example: 0102
+ 01: 01 was last written, or is to be written, to the
+ first module's shift register
+ 02: the same for second module
diff --git a/Documentation/ABI/testing/dev-kmsg b/Documentation/ABI/testing/dev-kmsg
index fff817efa508..f307506eb54c 100644
--- a/Documentation/ABI/testing/dev-kmsg
+++ b/Documentation/ABI/testing/dev-kmsg
@@ -12,7 +12,7 @@ Description: The /dev/kmsg character device node provides userspace access
The logged line can be prefixed with a <N> syslog prefix, which
carries the syslog priority and facility. The single decimal
prefix number is composed of the 3 lowest bits being the syslog
- priority and the higher bits the syslog facility number.
+ priority and the next 8 bits the syslog facility number.
If no prefix is given, the priority number is the default kernel
log priority and the facility number is set to LOG_USER (1). It
@@ -90,13 +90,12 @@ Description: The /dev/kmsg character device node provides userspace access
+sound:card0 - subsystem:devname
The flags field carries '-' by default. A 'c' indicates a
- fragment of a line. All following fragments are flagged with
- '+'. Note, that these hints about continuation lines are not
- necessarily correct, and the stream could be interleaved with
- unrelated messages, but merging the lines in the output
- usually produces better human readable results. A similar
- logic is used internally when messages are printed to the
- console, /proc/kmsg or the syslog() syscall.
+ fragment of a line. Note, that these hints about continuation
+ lines are not necessarily correct, and the stream could be
+ interleaved with unrelated messages, but merging the lines in
+ the output usually produces better human readable results. A
+ similar logic is used internally when messages are printed to
+ the console, /proc/kmsg or the syslog() syscall.
By default, kernel tries to avoid fragments by concatenating
when it can and fragments are rare; however, when extended
diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy
index fc376a323908..29ebe9afdac4 100644
--- a/Documentation/ABI/testing/ima_policy
+++ b/Documentation/ABI/testing/ima_policy
@@ -37,7 +37,7 @@ Description:
euid:= decimal value
fowner:= decimal value
lsm: are LSM specific
- option: appraise_type:= [imasig]
+ option: appraise_type:= [imasig] [imasig|modsig]
template:= name of a defined IMA template type
(eg, ima-ng). Only valid when action is "measure".
pcr:= decimal value
@@ -105,3 +105,7 @@ Description:
measure func=KEXEC_KERNEL_CHECK pcr=4
measure func=KEXEC_INITRAMFS_CHECK pcr=5
+
+ Example of appraise rule allowing modsig appended signatures:
+
+ appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32
index da9822309f07..0e66ae9b0071 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32
+++ b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32
@@ -13,4 +13,4 @@ Description:
error on writing
If DFSDM input is SPI Slave:
Reading returns value previously set.
- Writing value before starting conversions. \ No newline at end of file
+ Writing value before starting conversions.
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
index 161c147d3c40..b7259234ad70 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
+++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
@@ -91,29 +91,6 @@ Description:
When counting down the counter start from preset value
and fire event when reach 0.
-What: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
-KernelVersion: 4.12
-Contact: benjamin.gaignard@st.com
-Description:
- Reading returns the list possible quadrature modes.
-
-What: /sys/bus/iio/devices/iio:deviceX/in_count0_quadrature_mode
-KernelVersion: 4.12
-Contact: benjamin.gaignard@st.com
-Description:
- Configure the device counter quadrature modes:
- channel_A:
- Encoder A input servers as the count input and B as
- the UP/DOWN direction control input.
-
- channel_B:
- Encoder B input serves as the count input and A as
- the UP/DOWN direction control input.
-
- quadrature:
- Encoder A and B inputs are mixed to get direction
- and count with a scale of 0.25.
-
What: /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available
KernelVersion: 4.12
Contact: benjamin.gaignard@st.com
diff --git a/Documentation/ABI/testing/sysfs-bus-intel_th-devices-msc b/Documentation/ABI/testing/sysfs-bus-intel_th-devices-msc
index f54ae244f3f1..456cb62b384c 100644
--- a/Documentation/ABI/testing/sysfs-bus-intel_th-devices-msc
+++ b/Documentation/ABI/testing/sysfs-bus-intel_th-devices-msc
@@ -12,7 +12,8 @@ Description: (RW) Configure MSC operating mode:
- "single", for contiguous buffer mode (high-order alloc);
- "multi", for multiblock mode;
- "ExI", for DCI handler mode;
- - "debug", for debug mode.
+ - "debug", for debug mode;
+ - any of the currently loaded buffer sinks.
If operating mode changes, existing buffer is deallocated,
provided there are no active users and tracing is not enabled,
otherwise the write will fail.
diff --git a/Documentation/ABI/testing/sysfs-bus-moxtet-devices b/Documentation/ABI/testing/sysfs-bus-moxtet-devices
new file mode 100644
index 000000000000..355958527fa3
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-moxtet-devices
@@ -0,0 +1,17 @@
+What: /sys/bus/moxtet/devices/moxtet-<name>.<addr>/module_description
+Date: March 2019
+KernelVersion: 5.3
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) Moxtet module description. Format: string
+
+What: /sys/bus/moxtet/devices/moxtet-<name>.<addr>/module_id
+Date: March 2019
+KernelVersion: 5.3
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) Moxtet module ID. Format: %x
+
+What: /sys/bus/moxtet/devices/moxtet-<name>.<addr>/module_name
+Date: March 2019
+KernelVersion: 5.3
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) Moxtet module name. Format: string
diff --git a/Documentation/ABI/testing/sysfs-class-backlight b/Documentation/ABI/testing/sysfs-class-backlight
new file mode 100644
index 000000000000..3ab175a3f5cb
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-backlight
@@ -0,0 +1,26 @@
+What: /sys/class/backlight/<backlight>/scale
+Date: July 2019
+KernelVersion: 5.4
+Contact: Daniel Thompson <daniel.thompson@linaro.org>
+Description:
+ Description of the scale of the brightness curve.
+
+ The human eye senses brightness approximately logarithmically,
+ hence linear changes in brightness are perceived as being
+ non-linear. To achieve a linear perception of brightness changes
+ controls like sliders need to apply a logarithmic mapping for
+ backlights with a linear brightness curve.
+
+ Possible values of the attribute are:
+
+ unknown
+ The scale of the brightness curve is unknown.
+
+ linear
+ The brightness changes linearly with each step. Brightness
+ controls should apply a logarithmic mapping for a linear
+ perception.
+
+ non-linear
+ The brightness changes non-linearly with each step. Brightness
+ controls should use a linear mapping for a linear perception.
diff --git a/Documentation/ABI/testing/sysfs-class-mic.txt b/Documentation/ABI/testing/sysfs-class-mic
index 6ef682603179..6ef682603179 100644
--- a/Documentation/ABI/testing/sysfs-class-mic.txt
+++ b/Documentation/ABI/testing/sysfs-class-mic
diff --git a/Documentation/ABI/testing/sysfs-class-remoteproc b/Documentation/ABI/testing/sysfs-class-remoteproc
index c3afe9fab646..36094fbeb974 100644
--- a/Documentation/ABI/testing/sysfs-class-remoteproc
+++ b/Documentation/ABI/testing/sysfs-class-remoteproc
@@ -48,3 +48,13 @@ Description: Remote processor state
Writing "stop" will attempt to halt the remote processor and
return it to the "offline" state.
+
+What: /sys/class/remoteproc/.../name
+Date: August 2019
+KernelVersion: 5.4
+Contact: Suman Anna <s-anna@ti.com>
+Description: Remote processor name
+
+ Reports the name of the remote processor. This can be used by
+ userspace in exactly identifying a remote processor and ease
+ up the usage in modifying the 'firmware' or 'state' files.
diff --git a/Documentation/ABI/testing/sysfs-class-wakeup b/Documentation/ABI/testing/sysfs-class-wakeup
new file mode 100644
index 000000000000..754aab8b6dcd
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-wakeup
@@ -0,0 +1,76 @@
+What: /sys/class/wakeup/
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ The /sys/class/wakeup/ directory contains pointers to all
+ wakeup sources in the kernel at that moment in time.
+
+What: /sys/class/wakeup/.../name
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the name of the wakeup source.
+
+What: /sys/class/wakeup/.../active_count
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the number of times the wakeup source was
+ activated.
+
+What: /sys/class/wakeup/.../event_count
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the number of signaled wakeup events
+ associated with the wakeup source.
+
+What: /sys/class/wakeup/.../wakeup_count
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the number of times the wakeup source might
+ abort suspend.
+
+What: /sys/class/wakeup/.../expire_count
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the number of times the wakeup source's
+ timeout has expired.
+
+What: /sys/class/wakeup/.../active_time_ms
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the amount of time the wakeup source has
+ been continuously active, in milliseconds. If the wakeup
+ source is not active, this file contains '0'.
+
+What: /sys/class/wakeup/.../total_time_ms
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the total amount of time this wakeup source
+ has been active, in milliseconds.
+
+What: /sys/class/wakeup/.../max_time_ms
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the maximum amount of time this wakeup
+ source has been continuously active, in milliseconds.
+
+What: /sys/class/wakeup/.../last_change_ms
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ This file contains the monotonic clock time when the wakeup
+ source was touched last time, in milliseconds.
+
+What: /sys/class/wakeup/.../prevent_suspend_time_ms
+Date: June 2019
+Contact: Tri Vo <trong@android.com>
+Description:
+ The file contains the total amount of time this wakeup source
+ has been preventing autosleep, in milliseconds.
diff --git a/Documentation/ABI/testing/sysfs-class-watchdog b/Documentation/ABI/testing/sysfs-class-watchdog
index 6317ade5ad19..675f9b537661 100644
--- a/Documentation/ABI/testing/sysfs-class-watchdog
+++ b/Documentation/ABI/testing/sysfs-class-watchdog
@@ -72,3 +72,37 @@ Description:
It is a read/write file. When read, the currently assigned
pretimeout governor is returned. When written, it sets
the pretimeout governor.
+
+What: /sys/class/watchdog/watchdog1/access_cs0
+Date: August 2019
+Contact: Ivan Mikhaylov <i.mikhaylov@yadro.com>,
+ Alexander Amelkin <a.amelkin@yadro.com>
+Description:
+ It is a read/write file. This attribute exists only if the
+ system has booted from the alternate flash chip due to
+ expiration of a watchdog timer of AST2400/AST2500 when
+ alternate boot function was enabled with 'aspeed,alt-boot'
+ devicetree option for that watchdog or with an appropriate
+ h/w strapping (for WDT2 only).
+
+ At alternate flash the 'access_cs0' sysfs node provides:
+ ast2400: a way to get access to the primary SPI flash
+ chip at CS0 after booting from the alternate
+ chip at CS1.
+ ast2500: a way to restore the normal address mapping
+ from (CS0->CS1, CS1->CS0) to (CS0->CS0,
+ CS1->CS1).
+
+ Clearing the boot code selection and timeout counter also
+ resets to the initial state the chip select line mapping. When
+ the SoC is in normal mapping state (i.e. booted from CS0),
+ clearing those bits does nothing for both versions of the SoC.
+ For alternate boot mode (booted from CS1 due to wdt2
+ expiration) the behavior differs as described above.
+
+ This option can be used with wdt2 (watchdog1) only.
+
+ When read, the current status of the boot code selection is
+ shown. When written with any non-zero value, it clears
+ the boot code selection and the timeout counter, which results
+ in chipselect reset for AST2400/AST2500.
diff --git a/Documentation/ABI/testing/sysfs-devices-platform-stratix10-rsu b/Documentation/ABI/testing/sysfs-devices-platform-stratix10-rsu
new file mode 100644
index 000000000000..ae9af984471a
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-platform-stratix10-rsu
@@ -0,0 +1,128 @@
+ Intel Stratix10 Remote System Update (RSU) device attributes
+
+What: /sys/devices/platform/stratix10-rsu.0/current_image
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (RO) the address in flash of currently running image.
+
+What: /sys/devices/platform/stratix10-rsu.0/fail_image
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (RO) the address in flash of failed image.
+
+What: /sys/devices/platform/stratix10-rsu.0/state
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (RO) the state of RSU system.
+ The state field has two parts: major error code in
+ upper 16 bits and minor error code in lower 16 bits.
+
+ b[15:0]
+ Currently used only when major error is 0xF006
+ (CPU watchdog timeout), in which case the minor
+ error code is the value reported by CPU to
+ firmware through the RSU notify command before
+ the watchdog timeout occurs.
+
+ b[31:16]
+ 0xF001 bitstream error
+ 0xF002 hardware access failure
+ 0xF003 bitstream corruption
+ 0xF004 internal error
+ 0xF005 device error
+ 0xF006 CPU watchdog timeout
+ 0xF007 internal unknown error
+
+What: /sys/devices/platform/stratix10-rsu.0/version
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (RO) the version number of RSU firmware. 19.3 or late
+ version includes information about the firmware which
+ reported the error.
+
+ pre 19.3:
+ b[31:0]
+ 0x0 version number
+
+ 19.3 or late:
+ b[15:0]
+ 0x1 version number
+ b[31:16]
+ 0x0 no error
+ 0x0DCF Decision CMF error
+ 0x0ACF Application CMF error
+
+What: /sys/devices/platform/stratix10-rsu.0/error_location
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (RO) the error offset inside the image that failed.
+
+What: /sys/devices/platform/stratix10-rsu.0/error_details
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (RO) error code.
+
+What: /sys/devices/platform/stratix10-rsu.0/retry_counter
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (RO) the current image's retry counter, which is used by
+ user to know how many times the images is still allowed
+ to reload itself before giving up and starting RSU
+ fail-over flow.
+
+What: /sys/devices/platform/stratix10-rsu.0/reboot_image
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (WO) the address in flash of image to be loaded on next
+ reboot command.
+
+What: /sys/devices/platform/stratix10-rsu.0/notify
+Date: August 2019
+KernelVersion: 5.4
+Contact: Richard Gong <richard.gong@linux.intel.com>
+Description:
+ (WO) client to notify firmware with different actions.
+
+ b[15:0]
+ inform firmware the current software execution
+ stage.
+ 0 the first stage bootloader didn't run or
+ didn't reach the point of launching second
+ stage bootloader.
+ 1 failed in second bootloader or didn't get
+ to the point of launching the operating
+ system.
+ 2 both first and second stage bootloader ran
+ and the operating system launch was
+ attempted.
+
+ b[16]
+ 1 firmware to reset current image retry
+ counter.
+ 0 no action.
+
+ b[17]
+ 1 firmware to clear RSU log
+ 0 no action.
+
+ b[18]
+ this is negative logic
+ 1 no action
+ 0 firmware record the notify code defined
+ in b[15:0].
diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power
index 80a00f7b6667..1763e64dd152 100644
--- a/Documentation/ABI/testing/sysfs-devices-power
+++ b/Documentation/ABI/testing/sysfs-devices-power
@@ -260,3 +260,12 @@ Description:
This attribute has no effect on system-wide suspend/resume and
hibernation.
+
+What: /sys/devices/.../power/runtime_status
+Date: April 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power/runtime_status attribute contains
+ the current runtime PM status of the device, which may be
+ "suspended", "suspending", "resuming", "active", "error" (fatal
+ error), or "unsupported" (runtime PM is disabled).
diff --git a/Documentation/ABI/testing/sysfs-devices-soc b/Documentation/ABI/testing/sysfs-devices-soc
index 6d9cc253f2b2..ba3a3fac0ee1 100644
--- a/Documentation/ABI/testing/sysfs-devices-soc
+++ b/Documentation/ABI/testing/sysfs-devices-soc
@@ -26,6 +26,13 @@ Description:
Read-only attribute common to all SoCs. Contains SoC family name
(e.g. DB8500).
+What: /sys/devices/socX/serial_number
+Date: January 2019
+contact: Bjorn Andersson <bjorn.andersson@linaro.org>
+Description:
+ Read-only attribute supported by most SoCs. Contains the SoC's
+ serial number, if available.
+
What: /sys/devices/socX/soc_id
Date: January 2012
contact: Lee Jones <lee.jones@linaro.org>
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 5f7d7b14fa44..06d0931119cc 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -562,3 +562,13 @@ Description: Umwait control
or C0.2 state. The time is an unsigned 32-bit number.
Note that a value of zero means there is no limit.
Low order two bits must be zero.
+
+What: /sys/devices/system/cpu/svm
+Date: August 2019
+Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
+ Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Description: Secure Virtual Machine
+
+ If 1, it means the system is using the Protected Execution
+ Facility in POWER9 and newer processors. i.e., it is a Secure
+ Virtual Machine.
diff --git a/Documentation/ABI/testing/sysfs-driver-habanalabs b/Documentation/ABI/testing/sysfs-driver-habanalabs
index f433fc6db3c6..782df74042ed 100644
--- a/Documentation/ABI/testing/sysfs-driver-habanalabs
+++ b/Documentation/ABI/testing/sysfs-driver-habanalabs
@@ -57,6 +57,7 @@ KernelVersion: 5.1
Contact: oded.gabbay@gmail.com
Description: Allows the user to set the maximum clock frequency for MME, TPC
and IC when the power management profile is set to "automatic".
+ This property is valid only for the Goya ASIC family
What: /sys/class/habanalabs/hl<n>/ic_clk
Date: Jan 2019
@@ -127,8 +128,8 @@ Description: Power management profile. Values are "auto", "manual". In "auto"
the max clock frequency to a low value when there are no user
processes that are opened on the device's file. In "manual"
mode, the user sets the maximum clock frequency by writing to
- ic_clk, mme_clk and tpc_clk
-
+ ic_clk, mme_clk and tpc_clk. This property is valid only for
+ the Goya ASIC family
What: /sys/class/habanalabs/hl<n>/preboot_btl_ver
Date: Jan 2019
@@ -186,11 +187,4 @@ What: /sys/class/habanalabs/hl<n>/uboot_ver
Date: Jan 2019
KernelVersion: 5.1
Contact: oded.gabbay@gmail.com
-Description: Version of the u-boot running on the device's CPU
-
-What: /sys/class/habanalabs/hl<n>/write_open_cnt
-Date: Jan 2019
-KernelVersion: 5.1
-Contact: oded.gabbay@gmail.com
-Description: Displays the total number of user processes that are currently
- opened on the device's file
+Description: Version of the u-boot running on the device's CPU \ No newline at end of file
diff --git a/Documentation/ABI/testing/sysfs-firmware-efi b/Documentation/ABI/testing/sysfs-firmware-efi
index e794eac32a90..5e4d0b27cdfe 100644
--- a/Documentation/ABI/testing/sysfs-firmware-efi
+++ b/Documentation/ABI/testing/sysfs-firmware-efi
@@ -28,3 +28,11 @@ Description: Displays the physical addresses of all EFI Configuration
versions are always printed first, i.e. ACPI20 comes
before ACPI.
Users: dmidecode
+
+What: /sys/firmware/efi/tables/rci2
+Date: July 2019
+Contact: Narendra K <Narendra.K@dell.com>, linux-bugs@dell.com
+Description: Displays the content of the Runtime Configuration Interface
+ Table version 2 on Dell EMC PowerEdge systems in binary format
+Users: It is used by Dell EMC OpenManage Server Administrator tool to
+ populate BIOS setup page.
diff --git a/Documentation/ABI/testing/sysfs-firmware-turris-mox-rwtm b/Documentation/ABI/testing/sysfs-firmware-turris-mox-rwtm
new file mode 100644
index 000000000000..15595fab88d1
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-turris-mox-rwtm
@@ -0,0 +1,37 @@
+What: /sys/firmware/turris-mox-rwtm/board_version
+Date: August 2019
+KernelVersion: 5.4
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) Board version burned into eFuses of this Turris Mox board.
+ Format: %i
+
+What: /sys/firmware/turris-mox-rwtm/mac_address*
+Date: August 2019
+KernelVersion: 5.4
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) MAC addresses burned into eFuses of this Turris Mox board.
+ Format: %pM
+
+What: /sys/firmware/turris-mox-rwtm/pubkey
+Date: August 2019
+KernelVersion: 5.4
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) ECDSA public key (in pubkey hex compressed form) computed
+ as pair to the ECDSA private key burned into eFuses of this
+ Turris Mox Board.
+ Format: string
+
+What: /sys/firmware/turris-mox-rwtm/ram_size
+Date: August 2019
+KernelVersion: 5.4
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) RAM size in MiB of this Turris Mox board as was detected
+ during manufacturing and burned into eFuses. Can be 512 or 1024.
+ Format: %i
+
+What: /sys/firmware/turris-mox-rwtm/serial_number
+Date: August 2019
+KernelVersion: 5.4
+Contact: Marek Behún <marek.behun@nic.cz>
+Description: (R) Serial number burned into eFuses of this Turris Mox device.
+ Format: %016X
diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index dca326e0ee3e..7ab2b1b5e255 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -251,3 +251,10 @@ Description:
If checkpoint=disable, it displays the number of blocks that are unusable.
If checkpoint=enable it displays the enumber of blocks that would be unusable
if checkpoint=disable were to be set.
+
+What: /sys/fs/f2fs/<disk>/encoding
+Date July 2019
+Contact: "Daniel Rosenberg" <drosen@google.com>
+Description:
+ Displays name and version of the encoding set for the filesystem.
+ If no encoding is set, displays (none)
diff --git a/Documentation/ABI/testing/sysfs-kernel-btf b/Documentation/ABI/testing/sysfs-kernel-btf
new file mode 100644
index 000000000000..2c9744b2cd59
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-btf
@@ -0,0 +1,17 @@
+What: /sys/kernel/btf
+Date: Aug 2019
+KernelVersion: 5.5
+Contact: bpf@vger.kernel.org
+Description:
+ Contains BTF type information and related data for kernel and
+ kernel modules.
+
+What: /sys/kernel/btf/vmlinux
+Date: Aug 2019
+KernelVersion: 5.5
+Contact: bpf@vger.kernel.org
+Description:
+ Read-only binary attribute exposing kernel's own BTF type
+ information with description of all internal kernel types. See
+ Documentation/bpf/btf.rst for detailed description of format
+ itself.
diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab
index 29601d93a1c2..ed35833ad7f0 100644
--- a/Documentation/ABI/testing/sysfs-kernel-slab
+++ b/Documentation/ABI/testing/sysfs-kernel-slab
@@ -429,10 +429,15 @@ KernelVersion: 2.6.22
Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
Christoph Lameter <cl@linux-foundation.org>
Description:
- The shrink file is written when memory should be reclaimed from
- a cache. Empty partial slabs are freed and the partial list is
- sorted so the slabs with the fewest available objects are used
- first.
+ The shrink file is used to reclaim unused slab cache
+ memory from a cache. Empty per-cpu or partial slabs
+ are freed and the partial list is sorted so the slabs
+ with the fewest available objects are used first.
+ It only accepts a value of "1" on write for shrinking
+ the cache. Other input values are considered invalid.
+ Shrinking slab caches might be expensive and can
+ adversely impact other running applications. So it
+ should be used with care.
What: /sys/kernel/slab/cache/slab_size
Date: May 2007
diff --git a/Documentation/ABI/testing/sysfs-platform-dfl-fme b/Documentation/ABI/testing/sysfs-platform-dfl-fme
index 8fa4febfa4b2..72634d3ae4f4 100644
--- a/Documentation/ABI/testing/sysfs-platform-dfl-fme
+++ b/Documentation/ABI/testing/sysfs-platform-dfl-fme
@@ -21,3 +21,88 @@ Contact: Wu Hao <hao.wu@intel.com>
Description: Read-only. It returns Bitstream (static FPGA region) meta
data, which includes the synthesis date, seed and other
information of this static FPGA region.
+
+What: /sys/bus/platform/devices/dfl-fme.0/cache_size
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. It returns cache size of this FPGA device.
+
+What: /sys/bus/platform/devices/dfl-fme.0/fabric_version
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. It returns fabric version of this FPGA device.
+ Userspace applications need this information to select
+ best data channels per different fabric design.
+
+What: /sys/bus/platform/devices/dfl-fme.0/socket_id
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. It returns socket_id to indicate which socket
+ this FPGA belongs to, only valid for integrated solution.
+ User only needs this information, in case standard numa node
+ can't provide correct information.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/pcie0_errors
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-Write. Read this file for errors detected on pcie0 link.
+ Write this file to clear errors logged in pcie0_errors. Write
+ fails with -EINVAL if input parsing fails or input error code
+ doesn't match.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/pcie1_errors
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-Write. Read this file for errors detected on pcie1 link.
+ Write this file to clear errors logged in pcie1_errors. Write
+ fails with -EINVAL if input parsing fails or input error code
+ doesn't match.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/nonfatal_errors
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. It returns non-fatal errors detected.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/catfatal_errors
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. It returns catastrophic and fatal errors detected.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/inject_errors
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-Write. Read this file to check errors injected. Write this
+ file to inject errors for testing purpose. Write fails with
+ -EINVAL if input parsing fails or input inject error code isn't
+ supported.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/fme_errors
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-Write. Read this file to get errors detected on FME.
+ Write this file to clear errors logged in fme_errors. Write
+ fials with -EINVAL if input parsing fails or input error code
+ doesn't match.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/first_error
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. Read this file to get the first error detected by
+ hardware.
+
+What: /sys/bus/platform/devices/dfl-fme.0/errors/next_error
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. Read this file to get the second error detected by
+ hardware.
diff --git a/Documentation/ABI/testing/sysfs-platform-dfl-port b/Documentation/ABI/testing/sysfs-platform-dfl-port
index 6a92dda517b0..65658267fcc0 100644
--- a/Documentation/ABI/testing/sysfs-platform-dfl-port
+++ b/Documentation/ABI/testing/sysfs-platform-dfl-port
@@ -14,3 +14,88 @@ Description: Read-only. User can program different PR bitstreams to FPGA
Accelerator Function Unit (AFU) for different functions. It
returns uuid which could be used to identify which PR bitstream
is programmed in this AFU.
+
+What: /sys/bus/platform/devices/dfl-port.0/power_state
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. It reports the APx (AFU Power) state, different APx
+ means different throttling level. When reading this file, it
+ returns "0" - Normal / "1" - AP1 / "2" - AP2 / "6" - AP6.
+
+What: /sys/bus/platform/devices/dfl-port.0/ap1_event
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-write. Read this file for AP1 (AFU Power State 1) event.
+ It's used to indicate transient AP1 state. Write 1 to this
+ file to clear AP1 event.
+
+What: /sys/bus/platform/devices/dfl-port.0/ap2_event
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-write. Read this file for AP2 (AFU Power State 2) event.
+ It's used to indicate transient AP2 state. Write 1 to this
+ file to clear AP2 event.
+
+What: /sys/bus/platform/devices/dfl-port.0/ltr
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-write. Read or set AFU latency tolerance reporting value.
+ Set ltr to 1 if the AFU can tolerate latency >= 40us or set it
+ to 0 if it is latency sensitive.
+
+What: /sys/bus/platform/devices/dfl-port.0/userclk_freqcmd
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Write-only. User writes command to this interface to set
+ userclock to AFU.
+
+What: /sys/bus/platform/devices/dfl-port.0/userclk_freqsts
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. Read this file to get the status of issued command
+ to userclck_freqcmd.
+
+What: /sys/bus/platform/devices/dfl-port.0/userclk_freqcntrcmd
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Write-only. User writes command to this interface to set
+ userclock counter.
+
+What: /sys/bus/platform/devices/dfl-port.0/userclk_freqcntrsts
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. Read this file to get the status of issued command
+ to userclck_freqcntrcmd.
+
+What: /sys/bus/platform/devices/dfl-port.0/errors/errors
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-Write. Read this file to get errors detected on port and
+ Accelerated Function Unit (AFU). Write error code to this file
+ to clear errors. Write fails with -EINVAL if input parsing
+ fails or input error code doesn't match. Write fails with
+ -EBUSY or -ETIMEDOUT if error can't be cleared as hardware
+ in low power state (-EBUSY) or not respoding (-ETIMEDOUT).
+
+What: /sys/bus/platform/devices/dfl-port.0/errors/first_error
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. Read this file to get the first error detected by
+ hardware.
+
+What: /sys/bus/platform/devices/dfl-port.0/errors/first_malformed_req
+Date: August 2019
+KernelVersion: 5.4
+Contact: Wu Hao <hao.wu@intel.com>
+Description: Read-only. Read this file to get the first malformed request
+ captured by hardware.
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power
index 3c5130355011..6f87b9dd384b 100644
--- a/Documentation/ABI/testing/sysfs-power
+++ b/Documentation/ABI/testing/sysfs-power
@@ -301,3 +301,109 @@ Description:
Using this sysfs file will override any values that were
set using the kernel command line for disk offset.
+
+What: /sys/power/suspend_stats
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats directory contains suspend related
+ statistics.
+
+What: /sys/power/suspend_stats/success
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/success file contains the number
+ of times entering system sleep state succeeded.
+
+What: /sys/power/suspend_stats/fail
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/fail file contains the number
+ of times entering system sleep state failed.
+
+What: /sys/power/suspend_stats/failed_freeze
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_freeze file contains the
+ number of times freezing processes failed.
+
+What: /sys/power/suspend_stats/failed_prepare
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_prepare file contains the
+ number of times preparing all non-sysdev devices for
+ a system PM transition failed.
+
+What: /sys/power/suspend_stats/failed_resume
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_resume file contains the
+ number of times executing "resume" callbacks of
+ non-sysdev devices failed.
+
+What: /sys/power/suspend_stats/failed_resume_early
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_resume_early file contains
+ the number of times executing "early resume" callbacks
+ of devices failed.
+
+What: /sys/power/suspend_stats/failed_resume_noirq
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_resume_noirq file contains
+ the number of times executing "noirq resume" callbacks
+ of devices failed.
+
+What: /sys/power/suspend_stats/failed_suspend
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_suspend file contains
+ the number of times executing "suspend" callbacks
+ of all non-sysdev devices failed.
+
+What: /sys/power/suspend_stats/failed_suspend_late
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_suspend_late file contains
+ the number of times executing "late suspend" callbacks
+ of all devices failed.
+
+What: /sys/power/suspend_stats/failed_suspend_noirq
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/failed_suspend_noirq file contains
+ the number of times executing "noirq suspend" callbacks
+ of all devices failed.
+
+What: /sys/power/suspend_stats/last_failed_dev
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/last_failed_dev file contains
+ the last device for which a suspend/resume callback failed.
+
+What: /sys/power/suspend_stats/last_failed_errno
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/last_failed_errno file contains
+ the errno of the last failed attempt at entering
+ system sleep state.
+
+What: /sys/power/suspend_stats/last_failed_step
+Date: July 2019
+Contact: Kalesh Singh <kaleshsingh96@gmail.com>
+Description:
+ The /sys/power/suspend_stats/last_failed_step file contains
+ the last failed step in the suspend/resume path.