Merge tag 'char-misc-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc updates from Greg KH:
 "Here is the "big" char/misc driver patchset for 4.13-rc1.

  Lots of stuff in here, a large thunderbolt update, w1 driver header
  reorg, the new mux driver subsystem, google firmware driver updates,
  and a raft of other smaller things. Full details in the shortlog.

  All of these have been in linux-next for a while with the only
  reported issue being a merge problem with this tree and the jc-docs
  tree in the w1 documentation area"

* tag 'char-misc-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (147 commits)
  misc: apds990x: Use sysfs_match_string() helper
  mei: drop unreachable code in mei_start
  mei: validate the message header only in first fragment.
  DocBook: w1: Update W1 file locations and names in DocBook
  mux: adg792a: always require I2C support
  nvmem: rockchip-efuse: add support for rk322x-efuse
  nvmem: core: add locking to nvmem_find_cell
  nvmem: core: Call put_device() in nvmem_unregister()
  nvmem: core: fix leaks on registration errors
  nvmem: correct Broadcom OTP controller driver writes
  w1: Add subsystem kernel public interface
  drivers/fsi: Add module license to core driver
  drivers/fsi: Use asynchronous slave mode
  drivers/fsi: Add hub master support
  drivers/fsi: Add SCOM FSI client device driver
  drivers/fsi/gpio: Add tracepoints for GPIO master
  drivers/fsi: Add GPIO based FSI master
  drivers/fsi: Document FSI master sysfs files in ABI
  drivers/fsi: Add error handling for slave
  drivers/fsi: Add tracepoints for low-level operations
  ...

19 files changed, 1137 insertions, 11 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-fsi b/Documentation/ABI/testing/sysfs-bus-fsi
new file mode 100644
index 000000000000..57c806350d6c
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-fsi
@@ -0,0 +1,38 @@
+What:           /sys/bus/platform/devices/fsi-master/rescan
+Date:		May 2017
+KernelVersion:  4.12
+Contact:        cbostic@linux.vnet.ibm.com
+Description:
+                Initiates a FSI master scan for all connected slave devices
+		on its links.
+
+What:           /sys/bus/platform/devices/fsi-master/break
+Date:		May 2017
+KernelVersion:  4.12
+Contact:        cbostic@linux.vnet.ibm.com
+Description:
+		Sends an FSI BREAK command on a master's communication
+		link to any connnected slaves.  A BREAK resets connected
+		device's logic and preps it to receive further commands
+		from the master.
+
+What:           /sys/bus/platform/devices/fsi-master/slave@00:00/term
+Date:		May 2017
+KernelVersion:  4.12
+Contact:        cbostic@linux.vnet.ibm.com
+Description:
+		Sends an FSI terminate command from the master to its
+		connected slave. A terminate resets the slave's state machines
+		that control access to the internally connected engines.  In
+		addition the slave freezes its internal error register for
+		debugging purposes.  This command is also needed to abort any
+		ongoing operation in case of an expired 'Master Time Out'
+		timer.
+
+What:           /sys/bus/platform/devices/fsi-master/slave@00:00/raw
+Date:		May 2017
+KernelVersion:  4.12
+Contact:        cbostic@linux.vnet.ibm.com
+Description:
+		Provides a means of reading/writing a 32 bit value from/to a
+		specified FSI bus address.
diff --git a/Documentation/ABI/testing/sysfs-bus-thunderbolt b/Documentation/ABI/testing/sysfs-bus-thunderbolt
new file mode 100644
index 000000000000..2a98149943ea
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-thunderbolt
@@ -0,0 +1,110 @@
+What: /sys/bus/thunderbolt/devices/.../domainX/security
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	This attribute holds current Thunderbolt security level
+		set by the system BIOS. Possible values are:
+
+		none: All devices are automatically authorized
+		user: Devices are only authorized based on writing
+		      appropriate value to the authorized attribute
+		secure: Require devices that support secure connect at
+			minimum. User needs to authorize each device.
+		dponly: Automatically tunnel Display port (and USB). No
+			PCIe tunnels are created.
+
+What: /sys/bus/thunderbolt/devices/.../authorized
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	This attribute is used to authorize Thunderbolt devices
+		after they have been connected. If the device is not
+		authorized, no devices such as PCIe and Display port are
+		available to the system.
+
+		Contents of this attribute will be 0 when the device is not
+		yet authorized.
+
+		Possible values are supported:
+		1: The device will be authorized and connected
+
+		When key attribute contains 32 byte hex string the possible
+		values are:
+		1: The 32 byte hex string is added to the device NVM and
+		   the device is authorized.
+		2: Send a challenge based on the 32 byte hex string. If the
+		   challenge response from device is valid, the device is
+		   authorized. In case of failure errno will be ENOKEY if
+		   the device did not contain a key at all, and
+		   EKEYREJECTED if the challenge response did not match.
+
+What: /sys/bus/thunderbolt/devices/.../key
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	When a devices supports Thunderbolt secure connect it will
+		have this attribute. Writing 32 byte hex string changes
+		authorization to use the secure connection method instead.
+
+What:		/sys/bus/thunderbolt/devices/.../device
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	This attribute contains id of this device extracted from
+		the device DROM.
+
+What:		/sys/bus/thunderbolt/devices/.../device_name
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	This attribute contains name of this device extracted from
+		the device DROM.
+
+What:		/sys/bus/thunderbolt/devices/.../vendor
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	This attribute contains vendor id of this device extracted
+		from the device DROM.
+
+What:		/sys/bus/thunderbolt/devices/.../vendor_name
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	This attribute contains vendor name of this device extracted
+		from the device DROM.
+
+What:		/sys/bus/thunderbolt/devices/.../unique_id
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	This attribute contains unique_id string of this device.
+		This is either read from hardware registers (UUID on
+		newer hardware) or based on UID from the device DROM.
+		Can be used to uniquely identify particular device.
+
+What:		/sys/bus/thunderbolt/devices/.../nvm_version
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	If the device has upgradeable firmware the version
+		number is available here. Format: %x.%x, major.minor.
+		If the device is in safe mode reading the file returns
+		-ENODATA instead as the NVM version is not available.
+
+What:		/sys/bus/thunderbolt/devices/.../nvm_authenticate
+Date:		Sep 2017
+KernelVersion:	4.13
+Contact:	thunderbolt-software@lists.01.org
+Description:	When new NVM image is written to the non-active NVM
+		area (through non_activeX NVMem device), the
+		authentication procedure is started by writing 1 to
+		this file. If everything goes well, the device is
+		restarted with the new NVM firmware. If the image
+		verification fails an error code is returned instead.
+
+		When read holds status of the last authentication
+		operation if an error occurred during the process. This
+		is directly the status value from the DMA configuration
+		based mailbox before the device is power cycled. Writing
+		0 here clears the status.
diff --git a/Documentation/ABI/testing/sysfs-class-mux b/Documentation/ABI/testing/sysfs-class-mux
new file mode 100644
index 000000000000..8715f9c7bd4f
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-mux
@@ -0,0 +1,16 @@
+What:		/sys/class/mux/
+Date:		April 2017
+KernelVersion:	4.13
+Contact:	Peter Rosin <peda@axentia.se>
+Description:
+		The mux/ class sub-directory belongs to the Generic MUX
+		Framework and provides a sysfs interface for using MUX
+		controllers.
+
+What:		/sys/class/mux/muxchipN/
+Date:		April 2017
+KernelVersion:	4.13
+Contact:	Peter Rosin <peda@axentia.se>
+Description:
+		A /sys/class/mux/muxchipN directory is created for each
+		probed MUX chip where N is a simple enumeration.
diff --git a/Documentation/DocBook/w1.tmpl b/Documentation/DocBook/w1.tmpl
index b0228d4c81bb..c65cb27abef9 100644
--- a/Documentation/DocBook/w1.tmpl
+++ b/Documentation/DocBook/w1.tmpl
@@ -51,9 +51,9 @@
     <sect1 id="w1_internal_api">
       <title>W1 API internal to the kernel</title>
       <sect2 id="w1.h">
-        <title>drivers/w1/w1.h</title>
-        <para>W1 core functions.</para>
-!Idrivers/w1/w1.h
+        <title>include/linux/w1.h</title>
+        <para>W1 kernel API functions.</para>
+!Iinclude/linux/w1.h
       </sect2>
 
       <sect2 id="w1.c">
@@ -62,18 +62,18 @@
 !Idrivers/w1/w1.c
       </sect2>
 
-      <sect2 id="w1_family.h">
-        <title>drivers/w1/w1_family.h</title>
-        <para>Allows registering device family operations.</para>
-!Idrivers/w1/w1_family.h
-      </sect2>
-
       <sect2 id="w1_family.c">
         <title>drivers/w1/w1_family.c</title>
         <para>Allows registering device family operations.</para>
 !Edrivers/w1/w1_family.c
       </sect2>
 
+      <sect2 id="w1_internal.h">
+        <title>drivers/w1/w1_internal.h</title>
+        <para>W1 internal initialization for master devices.</para>
+!Idrivers/w1/w1_internal.h
+      </sect2>
+
       <sect2 id="w1_int.c">
         <title>drivers/w1/w1_int.c</title>
         <para>W1 internal initialization for master devices.</para>
diff --git a/Documentation/admin-guide/devices.txt b/Documentation/admin-guide/devices.txt
index c9cea2e39c21..6b71852dadc2 100644
--- a/Documentation/admin-guide/devices.txt
+++ b/Documentation/admin-guide/devices.txt
@@ -369,8 +369,10 @@
 		237 = /dev/loop-control Loopback control device
 		238 = /dev/vhost-net	Host kernel accelerator for virtio net
 		239 = /dev/uhid		User-space I/O driver support for HID subsystem
+		240 = /dev/userio	Serio driver testing device
+		241 = /dev/vhost-vsock	Host kernel driver for virtio vsock
 
-		240-254			Reserved for local use
+		242-254			Reserved for local use
 		255			Reserved for MISC_DYNAMIC_MINOR
 
   11 char	Raw keyboard device	(Linux/SPARC only)
diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst
index 8c60a8a32a1a..6d99a7ce6e21 100644
--- a/Documentation/admin-guide/index.rst
+++ b/Documentation/admin-guide/index.rst
@@ -61,6 +61,7 @@ configure specific aspects of kernel behavior to your liking.
    java
    ras
    pm/index
+   thunderbolt
 
 .. only::  subproject and html
 
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index d4c3b6c6ef92..783010e95f51 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -649,6 +649,13 @@
 			/proc/<pid>/coredump_filter.
 			See also Documentation/filesystems/proc.txt.
 
+	coresight_cpu_debug.enable
+			[ARM,ARM64]
+			Format: <bool>
+			Enable/disable the CPU sampling based debugging.
+			0: default value, disable debugging
+			1: enable debugging at boot time
+
 	cpuidle.off=1	[CPU_IDLE]
 			disable the cpuidle sub-system
 
diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst
new file mode 100644
index 000000000000..6a4cd1f159ca
--- /dev/null
+++ b/Documentation/admin-guide/thunderbolt.rst
@@ -0,0 +1,199 @@
+=============
+ Thunderbolt
+=============
+The interface presented here is not meant for end users. Instead there
+should be a userspace tool that handles all the low-level details, keeps
+database of the authorized devices and prompts user for new connections.
+
+More details about the sysfs interface for Thunderbolt devices can be
+found in ``Documentation/ABI/testing/sysfs-bus-thunderbolt``.
+
+Those users who just want to connect any device without any sort of
+manual work, can add following line to
+``/etc/udev/rules.d/99-local.rules``::
+
+  ACTION=="add", SUBSYSTEM=="thunderbolt", ATTR{authorized}=="0", ATTR{authorized}="1"
+
+This will authorize all devices automatically when they appear. However,
+keep in mind that this bypasses the security levels and makes the system
+vulnerable to DMA attacks.
+
+Security levels and how to use them
+-----------------------------------
+Starting from Intel Falcon Ridge Thunderbolt controller there are 4
+security levels available. The reason for these is the fact that the
+connected devices can be DMA masters and thus read contents of the host
+memory without CPU and OS knowing about it. There are ways to prevent
+this by setting up an IOMMU but it is not always available for various
+reasons.
+
+The security levels are as follows:
+
+  none
+    All devices are automatically connected by the firmware. No user
+    approval is needed. In BIOS settings this is typically called
+    *Legacy mode*.
+
+  user
+    User is asked whether the device is allowed to be connected.
+    Based on the device identification information available through
+    ``/sys/bus/thunderbolt/devices``. user then can do the decision.
+    In BIOS settings this is typically called *Unique ID*.
+
+  secure
+    User is asked whether the device is allowed to be connected. In
+    addition to UUID the device (if it supports secure connect) is sent
+    a challenge that should match the expected one based on a random key
+    written to ``key`` sysfs attribute. In BIOS settings this is
+    typically called *One time saved key*.
+
+  dponly
+    The firmware automatically creates tunnels for Display Port and
+    USB. No PCIe tunneling is done. In BIOS settings this is
+    typically called *Display Port Only*.
+
+The current security level can be read from
+``/sys/bus/thunderbolt/devices/domainX/security`` where ``domainX`` is
+the Thunderbolt domain the host controller manages. There is typically
+one domain per Thunderbolt host controller.
+
+If the security level reads as ``user`` or ``secure`` the connected
+device must be authorized by the user before PCIe tunnels are created
+(e.g the PCIe device appears).
+
+Each Thunderbolt device plugged in will appear in sysfs under
+``/sys/bus/thunderbolt/devices``. The device directory carries
+information that can be used to identify the particular device,
+including its name and UUID.
+
+Authorizing devices when security level is ``user`` or ``secure``
+-----------------------------------------------------------------
+When a device is plugged in it will appear in sysfs as follows::
+
+  /sys/bus/thunderbolt/devices/0-1/authorized	- 0
+  /sys/bus/thunderbolt/devices/0-1/device	- 0x8004
+  /sys/bus/thunderbolt/devices/0-1/device_name	- Thunderbolt to FireWire Adapter
+  /sys/bus/thunderbolt/devices/0-1/vendor	- 0x1
+  /sys/bus/thunderbolt/devices/0-1/vendor_name	- Apple, Inc.
+  /sys/bus/thunderbolt/devices/0-1/unique_id	- e0376f00-0300-0100-ffff-ffffffffffff
+
+The ``authorized`` attribute reads 0 which means no PCIe tunnels are
+created yet. The user can authorize the device by simply::
+
+  # echo 1 > /sys/bus/thunderbolt/devices/0-1/authorized
+
+This will create the PCIe tunnels and the device is now connected.
+
+If the device supports secure connect, and the domain security level is
+set to ``secure``, it has an additional attribute ``key`` which can hold
+a random 32 byte value used for authorization and challenging the device in
+future connects::
+
+  /sys/bus/thunderbolt/devices/0-3/authorized	- 0
+  /sys/bus/thunderbolt/devices/0-3/device	- 0x305
+  /sys/bus/thunderbolt/devices/0-3/device_name	- AKiTiO Thunder3 PCIe Box
+  /sys/bus/thunderbolt/devices/0-3/key		-
+  /sys/bus/thunderbolt/devices/0-3/vendor	- 0x41
+  /sys/bus/thunderbolt/devices/0-3/vendor_name	- inXtron
+  /sys/bus/thunderbolt/devices/0-3/unique_id	- dc010000-0000-8508-a22d-32ca6421cb16
+
+Notice the key is empty by default.
+
+If the user does not want to use secure connect it can just ``echo 1``
+to the ``authorized`` attribute and the PCIe tunnels will be created in
+the same way than in ``user`` security level.
+
+If the user wants to use secure connect, the first time the device is
+plugged a key needs to be created and send to the device::
+
+  # key=$(openssl rand -hex 32)
+  # echo $key > /sys/bus/thunderbolt/devices/0-3/key
+  # echo 1 > /sys/bus/thunderbolt/devices/0-3/authorized
+
+Now the device is connected (PCIe tunnels are created) and in addition
+the key is stored on the device NVM.
+
+Next time the device is plugged in the user can verify (challenge) the
+device using the same key::
+
+  # echo $key > /sys/bus/thunderbolt/devices/0-3/key
+  # echo 2 > /sys/bus/thunderbolt/devices/0-3/authorized
+
+If the challenge the device returns back matches the one we expect based
+on the key, the device is connected and the PCIe tunnels are created.
+However, if the challenge failed no tunnels are created and error is
+returned to the user.
+
+If the user still wants to connect the device it can either approve
+the device without a key or write new key and write 1 to the
+``authorized`` file to get the new key stored on the device NVM.
+
+Upgrading NVM on Thunderbolt device or host
+-------------------------------------------
+Since most of the functionality is handled in a firmware running on a
+host controller or a device, it is important that the firmware can be
+upgraded to the latest where possible bugs in it have been fixed.
+Typically OEMs provide this firmware from their support site.
+
+There is also a central site which has links where to download firmwares
+for some machines:
+
+  `Thunderbolt Updates <https://thunderbolttechnology.net/updates>`_
+
+Before you upgrade firmware on a device or host, please make sure it is
+the suitable. Failing to do that may render the device (or host) in a
+state where it cannot be used properly anymore without special tools!
+
+Host NVM upgrade on Apple Macs is not supported.
+
+Once the NVM image has been downloaded, you need to plug in a
+Thunderbolt device so that the host controller appears. It does not
+matter which device is connected (unless you are upgrading NVM on a
+device - then you need to connect that particular device).
+
+Note OEM-specific method to power the controller up ("force power") may
+be available for your system in which case there is no need to plug in a
+Thunderbolt device.
+
+After that we can write the firmware to the non-active parts of the NVM
+of the host or device. As an example here is how Intel NUC6i7KYK (Skull
+Canyon) Thunderbolt controller NVM is upgraded::
+
+  # dd if=KYK_TBT_FW_0018.bin of=/sys/bus/thunderbolt/devices/0-0/nvm_non_active0/nvmem
+
+Once the operation completes we can trigger NVM authentication and
+upgrade process as follows::
+
+  # echo 1 > /sys/bus/thunderbolt/devices/0-0/nvm_authenticate
+
+If no errors are returned, the host controller shortly disappears. Once
+it comes back the driver notices it and initiates a full power cycle.
+After a while the host controller appears again and this time it should
+be fully functional.
+
+We can verify that the new NVM firmware is active by running following
+commands::
+
+  # cat /sys/bus/thunderbolt/devices/0-0/nvm_authenticate
+  0x0
+  # cat /sys/bus/thunderbolt/devices/0-0/nvm_version
+  18.0
+
+If ``nvm_authenticate`` contains anything else than 0x0 it is the error
+code from the last authentication cycle, which means the authentication
+of the NVM image failed.
+
+Note names of the NVMem devices ``nvm_activeN`` and ``nvm_non_activeN``
+depends on the order they are registered in the NVMem subsystem. N in
+the name is the identifier added by the NVMem subsystem.
+
+Upgrading NVM when host controller is in safe mode
+--------------------------------------------------
+If the existing NVM is not properly authenticated (or is missing) the
+host controller goes into safe mode which means that only available
+functionality is flashing new NVM image. When in this mode the reading
+``nvm_version`` fails with ``ENODATA`` and the device identification
+information is missing.
+
+To recover from this mode, one needs to flash a valid NVM image to the
+host host controller in the same way it is done in the previous chapter.
diff --git a/Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt b/Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt
new file mode 100644
index 000000000000..298291211ea4
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt
@@ -0,0 +1,49 @@
+* CoreSight CPU Debug Component:
+
+CoreSight CPU debug component are compliant with the ARMv8 architecture
+reference manual (ARM DDI 0487A.k) Chapter 'Part H: External debug'. The
+external debug module is mainly used for two modes: self-hosted debug and
+external debug, and it can be accessed from mmio region from Coresight
+and eventually the debug module connects with CPU for debugging. And the
+debug module provides sample-based profiling extension, which can be used
+to sample CPU program counter, secure state and exception level, etc;
+usually every CPU has one dedicated debug module to be connected.
+
+Required properties:
+
+- compatible : should be "arm,coresight-cpu-debug"; supplemented with
+               "arm,primecell" since this driver is using the AMBA bus
+	       interface.
+
+- reg : physical base address and length of the register set.
+
+- clocks : the clock associated to this component.
+
+- clock-names : the name of the clock referenced by the code. Since we are
+                using the AMBA framework, the name of the clock providing
+		the interconnect should be "apb_pclk" and the clock is
+		mandatory. The interface between the debug logic and the
+		processor core is clocked by the internal CPU clock, so it
+		is enabled with CPU clock by default.
+
+- cpu : the CPU phandle the debug module is affined to. When omitted
+	the module is considered to belong to CPU0.
+
+Optional properties:
+
+- power-domains: a phandle to the debug power domain. We use "power-domains"
+                 binding to turn on the debug logic if it has own dedicated
+		 power domain and if necessary to use "cpuidle.off=1" or
+		 "nohlt" in the kernel command line or sysfs node to
+		 constrain idle states to ensure registers in the CPU power
+		 domain are accessible.
+
+Example:
+
+	debug@f6590000 {
+		compatible = "arm,coresight-cpu-debug","arm,primecell";
+		reg = <0 0xf6590000 0 0x1000>;
+		clocks = <&sys_ctrl HI6220_DAPB_CLK>;
+		clock-names = "apb_pclk";
+		cpu = <&cpu0>;
+	};
diff --git a/Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt b/Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt
new file mode 100644
index 000000000000..a767259dedad
--- /dev/null
+++ b/Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt
@@ -0,0 +1,24 @@
+Device-tree bindings for gpio-based FSI master driver
+-----------------------------------------------------
+
+Required properties:
+ - compatible = "fsi-master-gpio";
+ - clock-gpios = <gpio-descriptor>;	: GPIO for FSI clock
+ - data-gpios = <gpio-descriptor>;	: GPIO for FSI data signal
+
+Optional properties:
+ - enable-gpios = <gpio-descriptor>;	: GPIO for enable signal
+ - trans-gpios = <gpio-descriptor>;	: GPIO for voltage translator enable
+ - mux-gpios = <gpio-descriptor>;	: GPIO for pin multiplexing with other
+                                          functions (eg, external FSI masters)
+
+Examples:
+
+    fsi-master {
+        compatible = "fsi-master-gpio", "fsi-master";
+        clock-gpios = <&gpio 0>;
+        data-gpios = <&gpio 1>;
+        enable-gpios = <&gpio 2>;
+        trans-gpios = <&gpio 3>;
+        mux-gpios = <&gpio 4>;
+    }
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
new file mode 100644
index 000000000000..2907dab56298
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
@@ -0,0 +1,99 @@
+General Purpose I2C Bus Mux
+
+This binding describes an I2C bus multiplexer that uses a mux controller
+from the mux subsystem to route the I2C signals.
+
+                                  .-----.  .-----.
+                                  | dev |  | dev |
+    .------------.                '-----'  '-----'
+    | SoC        |                   |        |
+    |            |          .--------+--------'
+    |   .------. |  .------+    child bus A, on MUX value set to 0
+    |   | I2C  |-|--| Mux  |
+    |   '------' |  '--+---+    child bus B, on MUX value set to 1
+    |   .------. |     |    '----------+--------+--------.
+    |   | MUX- | |     |               |        |        |
+    |   | Ctrl |-|-----+            .-----.  .-----.  .-----.
+    |   '------' |                  | dev |  | dev |  | dev |
+    '------------'                  '-----'  '-----'  '-----'
+
+Required properties:
+- compatible: i2c-mux
+- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
+  port is connected to.
+- mux-controls: The phandle of the mux controller to use for operating the
+  mux.
+* Standard I2C mux properties. See i2c-mux.txt in this directory.
+* I2C child bus nodes. See i2c-mux.txt in this directory. The sub-bus number
+  is also the mux-controller state described in ../mux/mux-controller.txt
+
+Optional properties:
+- mux-locked: If present, explicitly allow unrelated I2C transactions on the
+  parent I2C adapter at these times:
+   + during setup of the multiplexer
+   + between setup of the multiplexer and the child bus I2C transaction
+   + between the child bus I2C transaction and releasing of the multiplexer
+   + during releasing of the multiplexer
+  However, I2C transactions to devices behind all I2C multiplexers connected
+  to the same parent adapter that this multiplexer is connected to are blocked
+  for the full duration of the complete multiplexed I2C transaction (i.e.
+  including the times covered by the above list).
+  If mux-locked is not present, the multiplexer is assumed to be parent-locked.
+  This means that no unrelated I2C transactions are allowed on the parent I2C
+  adapter for the complete multiplexed I2C transaction.
+  The properties of mux-locked and parent-locked multiplexers are discussed
+  in more detail in Documentation/i2c/i2c-topology.
+
+For each i2c child node, an I2C child bus will be created. They will
+be numbered based on their order in the device tree.
+
+Whenever an access is made to a device on a child bus, the value set
+in the relevant node's reg property will be set as the state in the
+mux controller.
+
+Example:
+	mux: mux-controller {
+		compatible = "gpio-mux";
+		#mux-control-cells = <0>;
+
+		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+			    <&pioA 1 GPIO_ACTIVE_HIGH>;
+	};
+
+	i2c-mux {
+		compatible = "i2c-mux";
+		mux-locked;
+		i2c-parent = <&i2c1>;
+
+		mux-controls = <&mux>;
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		i2c@1 {
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			ssd1307: oled@3c {
+				compatible = "solomon,ssd1307fb-i2c";
+				reg = <0x3c>;
+				pwms = <&pwm 4 3000>;
+				reset-gpios = <&gpio2 7 1>;
+				reset-active-low;
+			};
+		};
+
+		i2c@3 {
+			reg = <3>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			pca9555: pca9555@20 {
+				compatible = "nxp,pca9555";
+				gpio-controller;
+				#gpio-cells = <2>;
+				reg = <0x20>;
+			};
+		};
+	};
diff --git a/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt b/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
new file mode 100644
index 000000000000..c82794002595
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
@@ -0,0 +1,39 @@
+I/O channel multiplexer bindings
+
+If a multiplexer is used to select which hardware signal is fed to
+e.g. an ADC channel, these bindings describe that situation.
+
+Required properties:
+- compatible : "io-channel-mux"
+- io-channels : Channel node of the parent channel that has multiplexed
+		input.
+- io-channel-names : Should be "parent".
+- #address-cells = <1>;
+- #size-cells = <0>;
+- mux-controls : Mux controller node to use for operating the mux
+- channels : List of strings, labeling the mux controller states.
+
+For each non-empty string in the channels property, an io-channel will
+be created. The number of this io-channel is the same as the index into
+the list of strings in the channels property, and also matches the mux
+controller state. The mux controller state is described in
+../mux/mux-controller.txt
+
+Example:
+	mux: mux-controller {
+		compatible = "mux-gpio";
+		#mux-control-cells = <0>;
+
+		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+			    <&pioA 1 GPIO_ACTIVE_HIGH>;
+	};
+
+	adc-mux {
+		compatible = "io-channel-mux";
+		io-channels = <&adc 0>;
+		io-channel-names = "parent";
+
+		mux-controls = <&mux>;
+
+		channels = "sync", "in", "system-regulator";
+	};
diff --git a/Documentation/devicetree/bindings/mux/adi,adg792a.txt b/Documentation/devicetree/bindings/mux/adi,adg792a.txt
new file mode 100644
index 000000000000..96b787a69f50
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/adi,adg792a.txt
@@ -0,0 +1,75 @@
+Bindings for Analog Devices ADG792A/G Triple 4:1 Multiplexers
+
+Required properties:
+- compatible : "adi,adg792a" or "adi,adg792g"
+- #mux-control-cells : <0> if parallel (the three muxes are bound together
+  with a single mux controller controlling all three muxes), or <1> if
+  not (one mux controller for each mux).
+* Standard mux-controller bindings as described in mux-controller.txt
+
+Optional properties for ADG792G:
+- gpio-controller : if present, #gpio-cells below is required.
+- #gpio-cells : should be <2>
+			  - First cell is the GPO line number, i.e. 0 or 1
+			  - Second cell is used to specify active high (0)
+			    or active low (1)
+
+Optional properties:
+- idle-state : if present, array of states that the mux controllers will have
+  when idle. The special state MUX_IDLE_AS_IS is the default and
+  MUX_IDLE_DISCONNECT is also supported.
+
+States 0 through 3 correspond to signals A through D in the datasheet.
+
+Example:
+
+	/*
+	 * Three independent mux controllers (of which one is used).
+	 * Mux 0 is disconnected when idle, mux 1 idles in the previously
+	 * selected state and mux 2 idles with signal B.
+	 */
+	&i2c0 {
+		mux: mux-controller@50 {
+			compatible = "adi,adg792a";
+			reg = <0x50>;
+			#mux-control-cells = <1>;
+
+			idle-state = <MUX_IDLE_DISCONNECT MUX_IDLE_AS_IS 1>;
+		};
+	};
+
+	adc-mux {
+		compatible = "io-channel-mux";
+		io-channels = <&adc 0>;
+		io-channel-names = "parent";
+
+		mux-controls = <&mux 2>;
+
+		channels = "sync-1", "", "out";
+	};
+
+
+	/*
+	 * Three parallel muxes with one mux controller, useful e.g. if
+	 * the adc is differential, thus needing two signals to be muxed
+	 * simultaneously for correct operation.
+	 */
+	&i2c0 {
+		pmux: mux-controller@50 {
+			compatible = "adi,adg792a";
+			reg = <0x50>;
+			#mux-control-cells = <0>;
+
+			idle-state = <1>;
+		};
+	};
+
+	diff-adc-mux {
+		compatible = "io-channel-mux";
+		io-channels = <&adc 0>;
+		io-channel-names = "parent";
+
+		mux-controls = <&pmux>;
+
+		channels = "sync-1", "", "out";
+	};
diff --git a/Documentation/devicetree/bindings/mux/gpio-mux.txt b/Documentation/devicetree/bindings/mux/gpio-mux.txt
new file mode 100644
index 000000000000..b8f746344d80
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/gpio-mux.txt
@@ -0,0 +1,69 @@
+GPIO-based multiplexer controller bindings
+
+Define what GPIO pins are used to control a multiplexer. Or several
+multiplexers, if the same pins control more than one multiplexer.
+
+Required properties:
+- compatible : "gpio-mux"
+- mux-gpios : list of gpios used to control the multiplexer, least
+	      significant bit first.
+- #mux-control-cells : <0>
+* Standard mux-controller bindings as decribed in mux-controller.txt
+
+Optional properties:
+- idle-state : if present, the state the mux will have when idle. The
+	       special state MUX_IDLE_AS_IS is the default.
+
+The multiplexer state is defined as the number represented by the
+multiplexer GPIO pins, where the first pin is the least significant
+bit. An active pin is a binary 1, an inactive pin is a binary 0.
+
+Example:
+
+	mux: mux-controller {
+		compatible = "gpio-mux";
+		#mux-control-cells = <0>;
+
+		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+			    <&pioA 1 GPIO_ACTIVE_HIGH>;
+	};
+
+	adc-mux {
+		compatible = "io-channel-mux";
+		io-channels = <&adc 0>;
+		io-channel-names = "parent";
+
+		mux-controls = <&mux>;
+
+		channels = "sync-1", "in", "out", "sync-2";
+	};
+
+	i2c-mux {
+		compatible = "i2c-mux";
+		i2c-parent = <&i2c1>;
+
+		mux-controls = <&mux>;
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		i2c@0 {
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			ssd1307: oled@3c {
+				/* ... */
+			};
+		};
+
+		i2c@3 {
+			reg = <3>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			pca9555: pca9555@20 {
+				/* ... */
+			};
+		};
+	};
diff --git a/Documentation/devicetree/bindings/mux/mmio-mux.txt b/Documentation/devicetree/bindings/mux/mmio-mux.txt
new file mode 100644
index 000000000000..a9bfb4d8b6ac
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mmio-mux.txt
@@ -0,0 +1,60 @@
+MMIO register bitfield-based multiplexer controller bindings
+
+Define register bitfields to be used to control multiplexers. The parent
+device tree node must be a syscon node to provide register access.
+
+Required properties:
+- compatible : "mmio-mux"
+- #mux-control-cells : <1>
+- mux-reg-masks : an array of register offset and pre-shifted bitfield mask
+                  pairs, each describing a single mux control.
+* Standard mux-controller bindings as decribed in mux-controller.txt
+
+Optional properties:
+- idle-states : if present, the state the muxes will have when idle. The
+		special state MUX_IDLE_AS_IS is the default.
+
+The multiplexer state of each multiplexer is defined as the value of the
+bitfield described by the corresponding register offset and bitfield mask pair
+in the mux-reg-masks array, accessed through the parent syscon.
+
+Example:
+
+	syscon {
+		compatible = "syscon";
+
+		mux: mux-controller {
+			compatible = "mmio-mux";
+			#mux-control-cells = <1>;
+
+			mux-reg-masks = <0x3 0x30>, /* 0: reg 0x3, bits 5:4 */
+					<0x3 0x40>, /* 1: reg 0x3, bit 6 */
+			idle-states = <MUX_IDLE_AS_IS>, <0>;
+		};
+	};
+
+	video-mux {
+		compatible = "video-mux";
+		mux-controls = <&mux 0>;
+
+		ports {
+			/* inputs 0..3 */
+			port@0 {
+				reg = <0>;
+			};
+			port@1 {
+				reg = <1>;
+			};
+			port@2 {
+				reg = <2>;
+			};
+			port@3 {
+				reg = <3>;
+			};
+
+			/* output */
+			port@4 {
+				reg = <4>;
+			};
+		};
+	};
diff --git a/Documentation/devicetree/bindings/mux/mux-controller.txt b/Documentation/devicetree/bindings/mux/mux-controller.txt
new file mode 100644
index 000000000000..4f47e4bd2fa0
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mux-controller.txt
@@ -0,0 +1,157 @@
+Common multiplexer controller bindings
+======================================
+
+A multiplexer (or mux) controller will have one, or several, consumer devices
+that uses the mux controller. Thus, a mux controller can possibly control
+several parallel multiplexers. Presumably there will be at least one
+multiplexer needed by each consumer, but a single mux controller can of course
+control several multiplexers for a single consumer.
+
+A mux controller provides a number of states to its consumers, and the state
+space is a simple zero-based enumeration. I.e. 0-1 for a 2-way multiplexer,
+0-7 for an 8-way multiplexer, etc.
+
+
+Consumers
+---------
+
+Mux controller consumers should specify a list of mux controllers that they
+want to use with a property containing a 'mux-ctrl-list':
+
+	mux-ctrl-list ::= <single-mux-ctrl> [mux-ctrl-list]
+	single-mux-ctrl ::= <mux-ctrl-phandle> [mux-ctrl-specifier]
+	mux-ctrl-phandle : phandle to mux controller node
+	mux-ctrl-specifier : array of #mux-control-cells specifying the
+			     given mux controller (controller specific)
+
+Mux controller properties should be named "mux-controls". The exact meaning of
+each mux controller property must be documented in the device tree binding for
+each consumer. An optional property "mux-control-names" may contain a list of
+strings to label each of the mux controllers listed in the "mux-controls"
+property.
+
+Drivers for devices that use more than a single mux controller can use the
+"mux-control-names" property to map the name of the requested mux controller
+to an index into the list given by the "mux-controls" property.
+
+mux-ctrl-specifier typically encodes the chip-relative mux controller number.
+If the mux controller chip only provides a single mux controller, the
+mux-ctrl-specifier can typically be left out.
+
+Example:
+
+	/* One consumer of a 2-way mux controller (one GPIO-line) */
+	mux: mux-controller {
+		compatible = "gpio-mux";
+		#mux-control-cells = <0>;
+
+		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>;
+	};
+
+	adc-mux {
+		compatible = "io-channel-mux";
+		io-channels = <&adc 0>;
+		io-channel-names = "parent";
+
+		mux-controls = <&mux>;
+		mux-control-names = "adc";
+
+		channels = "sync", "in";
+	};
+
+Note that in the example above, specifying the "mux-control-names" is redundant
+because there is only one mux controller in the list. However, if the driver
+for the consumer node in fact asks for a named mux controller, that name is of
+course still required.
+
+	/*
+	 * Two consumers (one for an ADC line and one for an i2c bus) of
+	 * parallel 4-way multiplexers controlled by the same two GPIO-lines.
+	 */
+	mux: mux-controller {
+		compatible = "gpio-mux";
+		#mux-control-cells = <0>;
+
+		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+			    <&pioA 1 GPIO_ACTIVE_HIGH>;
+	};
+
+	adc-mux {
+		compatible = "io-channel-mux";
+		io-channels = <&adc 0>;
+		io-channel-names = "parent";
+
+		mux-controls = <&mux>;
+
+		channels = "sync-1", "in", "out", "sync-2";
+	};
+
+	i2c-mux {
+		compatible = "i2c-mux";
+		i2c-parent = <&i2c1>;
+
+		mux-controls = <&mux>;
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		i2c@0 {
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			ssd1307: oled@3c {
+				/* ... */
+			};
+		};
+
+		i2c@3 {
+			reg = <3>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			pca9555: pca9555@20 {
+				/* ... */
+			};
+		};
+	};
+
+
+Mux controller nodes
+--------------------
+
+Mux controller nodes must specify the number of cells used for the
+specifier using the '#mux-control-cells' property.
+
+Optionally, mux controller nodes can also specify the state the mux should
+have when it is idle. The idle-state property is used for this. If the
+idle-state is not present, the mux controller is typically left as is when
+it is idle. For multiplexer chips that expose several mux controllers, the
+idle-state property is an array with one idle state for each mux controller.
+
+The special value (-1) may be used to indicate that the mux should be left
+as is when it is idle. This is the default, but can still be useful for
+mux controller chips with more than one mux controller, particularly when
+there is a need to "step past" a mux controller and set some other idle
+state for a mux controller with a higher index.
+
+Some mux controllers have the ability to disconnect the input/output of the
+multiplexer. Using this disconnected high-impedance state as the idle state
+is indicated with idle state (-2).
+
+These constants are available in
+
+      #include <dt-bindings/mux/mux.h>
+
+as MUX_IDLE_AS_IS (-1) and MUX_IDLE_DISCONNECT (-2).
+
+An example mux controller node look like this (the adg972a chip is a triple
+4-way multiplexer):
+
+	mux: mux-controller@50 {
+		compatible = "adi,adg792a";
+		reg = <0x50>;
+		#mux-control-cells = <1>;
+
+		idle-state = <MUX_IDLE_DISCONNECT MUX_IDLE_AS_IS 2>;
+	};
diff --git a/Documentation/devicetree/bindings/nvmem/rockchip-efuse.txt b/Documentation/devicetree/bindings/nvmem/rockchip-efuse.txt
index 94aeeeabadd5..194926f77194 100644
--- a/Documentation/devicetree/bindings/nvmem/rockchip-efuse.txt
+++ b/Documentation/devicetree/bindings/nvmem/rockchip-efuse.txt
@@ -4,6 +4,7 @@ Required properties:
 - compatible: Should be one of the following.
   - "rockchip,rk3066a-efuse" - for RK3066a SoCs.
   - "rockchip,rk3188-efuse" - for RK3188 SoCs.
+  - "rockchip,rk322x-efuse" - for RK322x SoCs.
   - "rockchip,rk3288-efuse" - for RK3288 SoCs.
   - "rockchip,rk3399-efuse" - for RK3399 SoCs.
 - reg: Should contain the registers location and exact eFuse size
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index 6a6618f34440..2d132fcea0f8 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -337,7 +337,12 @@ MEM
   devm_kzalloc()
 
 MFD
- devm_mfd_add_devices()
+  devm_mfd_add_devices()
+
+MUX
+  devm_mux_chip_alloc()
+  devm_mux_chip_register()
+  devm_mux_control_get()
 
 PER-CPU MEM
   devm_alloc_percpu()
diff --git a/Documentation/trace/coresight-cpu-debug.txt b/Documentation/trace/coresight-cpu-debug.txt
new file mode 100644
index 000000000000..b3da1f90b861
--- /dev/null
+++ b/Documentation/trace/coresight-cpu-debug.txt
@@ -0,0 +1,175 @@
+		Coresight CPU Debug Module
+		==========================
+
+   Author:   Leo Yan <leo.yan@linaro.org>
+   Date:     April 5th, 2017
+
+Introduction
+------------
+
+Coresight CPU debug module is defined in ARMv8-a architecture reference manual
+(ARM DDI 0487A.k) Chapter 'Part H: External debug', the CPU can integrate
+debug module and it is mainly used for two modes: self-hosted debug and
+external debug. Usually the external debug mode is well known as the external
+debugger connects with SoC from JTAG port; on the other hand the program can
+explore debugging method which rely on self-hosted debug mode, this document
+is to focus on this part.
+
+The debug module provides sample-based profiling extension, which can be used
+to sample CPU program counter, secure state and exception level, etc; usually
+every CPU has one dedicated debug module to be connected. Based on self-hosted
+debug mechanism, Linux kernel can access these related registers from mmio
+region when the kernel panic happens. The callback notifier for kernel panic
+will dump related registers for every CPU; finally this is good for assistant
+analysis for panic.
+
+
+Implementation
+--------------
+
+- During driver registration, it uses EDDEVID and EDDEVID1 - two device ID
+  registers to decide if sample-based profiling is implemented or not. On some
+  platforms this hardware feature is fully or partially implemented; and if
+  this feature is not supported then registration will fail.
+
+- At the time this documentation was written, the debug driver mainly relies on
+  information gathered by the kernel panic callback notifier from three
+  sampling registers: EDPCSR, EDVIDSR and EDCIDSR: from EDPCSR we can get
+  program counter; EDVIDSR has information for secure state, exception level,
+  bit width, etc; EDCIDSR is context ID value which contains the sampled value
+  of CONTEXTIDR_EL1.
+
+- The driver supports a CPU running in either AArch64 or AArch32 mode. The
+  registers naming convention is a bit different between them, AArch64 uses
+  'ED' for register prefix (ARM DDI 0487A.k, chapter H9.1) and AArch32 uses
+  'DBG' as prefix (ARM DDI 0487A.k, chapter G5.1). The driver is unified to
+  use AArch64 naming convention.
+
+- ARMv8-a (ARM DDI 0487A.k) and ARMv7-a (ARM DDI 0406C.b) have different
+  register bits definition. So the driver consolidates two difference:
+
+  If PCSROffset=0b0000, on ARMv8-a the feature of EDPCSR is not implemented;
+  but ARMv7-a defines "PCSR samples are offset by a value that depends on the
+  instruction set state". For ARMv7-a, the driver checks furthermore if CPU
+  runs with ARM or thumb instruction set and calibrate PCSR value, the
+  detailed description for offset is in ARMv7-a ARM (ARM DDI 0406C.b) chapter
+  C11.11.34 "DBGPCSR, Program Counter Sampling Register".
+
+  If PCSROffset=0b0010, ARMv8-a defines "EDPCSR implemented, and samples have
+  no offset applied and do not sample the instruction set state in AArch32
+  state". So on ARMv8 if EDDEVID1.PCSROffset is 0b0010 and the CPU operates
+  in AArch32 state, EDPCSR is not sampled; when the CPU operates in AArch64
+  state EDPCSR is sampled and no offset are applied.
+
+
+Clock and power domain
+----------------------
+
+Before accessing debug registers, we should ensure the clock and power domain
+have been enabled properly. In ARMv8-a ARM (ARM DDI 0487A.k) chapter 'H9.1
+Debug registers', the debug registers are spread into two domains: the debug
+domain and the CPU domain.
+
+                                +---------------+
+                                |               |
+                                |               |
+                     +----------+--+            |
+        dbg_clock -->|          |**|            |<-- cpu_clock
+                     |    Debug |**|   CPU      |
+ dbg_power_domain -->|          |**|            |<-- cpu_power_domain
+                     +----------+--+            |
+                                |               |
+                                |               |
+                                +---------------+
+
+For debug domain, the user uses DT binding "clocks" and "power-domains" to
+specify the corresponding clock source and power supply for the debug logic.
+The driver calls the pm_runtime_{put|get} operations as needed to handle the
+debug power domain.
+
+For CPU domain, the different SoC designs have different power management
+schemes and finally this heavily impacts external debug module. So we can
+divide into below cases:
+
+- On systems with a sane power controller which can behave correctly with
+  respect to CPU power domain, the CPU power domain can be controlled by
+  register EDPRCR in driver. The driver firstly writes bit EDPRCR.COREPURQ
+  to power up the CPU, and then writes bit EDPRCR.CORENPDRQ for emulation
+  of CPU power down. As result, this can ensure the CPU power domain is
+  powered on properly during the period when access debug related registers;
+
+- Some designs will power down an entire cluster if all CPUs on the cluster
+  are powered down - including the parts of the debug registers that should
+  remain powered in the debug power domain. The bits in EDPRCR are not
+  respected in these cases, so these designs do not support debug over
+  power down in the way that the CoreSight / Debug designers anticipated.
+  This means that even checking EDPRSR has the potential to cause a bus hang
+  if the target register is unpowered.
+
+  In this case, accessing to the debug registers while they are not powered
+  is a recipe for disaster; so we need preventing CPU low power states at boot
+  time or when user enable module at the run time. Please see chapter
+  "How to use the module" for detailed usage info for this.
+
+
+Device Tree Bindings
+--------------------
+
+See Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt for details.
+
+
+How to use the module
+---------------------
+
+If you want to enable debugging functionality at boot time, you can add
+"coresight_cpu_debug.enable=1" to the kernel command line parameter.
+
+The driver also can work as module, so can enable the debugging when insmod
+module:
+# insmod coresight_cpu_debug.ko debug=1
+
+When boot time or insmod module you have not enabled the debugging, the driver
+uses the debugfs file system to provide a knob to dynamically enable or disable
+debugging:
+
+To enable it, write a '1' into /sys/kernel/debug/coresight_cpu_debug/enable:
+# echo 1 > /sys/kernel/debug/coresight_cpu_debug/enable
+
+To disable it, write a '0' into /sys/kernel/debug/coresight_cpu_debug/enable:
+# echo 0 > /sys/kernel/debug/coresight_cpu_debug/enable
+
+As explained in chapter "Clock and power domain", if you are working on one
+platform which has idle states to power off debug logic and the power
+controller cannot work well for the request from EDPRCR, then you should
+firstly constraint CPU idle states before enable CPU debugging feature; so can
+ensure the accessing to debug logic.
+
+If you want to limit idle states at boot time, you can use "nohlt" or
+"cpuidle.off=1" in the kernel command line.
+
+At the runtime you can disable idle states with below methods:
+
+Set latency request to /dev/cpu_dma_latency to disable all CPUs specific idle
+states (if latency = 0uS then disable all idle states):
+# echo "what_ever_latency_you_need_in_uS" > /dev/cpu_dma_latency
+
+Disable specific CPU's specific idle state:
+# echo 1 > /sys/devices/system/cpu/cpu$cpu/cpuidle/state$state/disable
+
+
+Output format
+-------------
+
+Here is an example of the debugging output format:
+
+ARM external debug module:
+coresight-cpu-debug 850000.debug: CPU[0]:
+coresight-cpu-debug 850000.debug:  EDPRSR:  00000001 (Power:On DLK:Unlock)
+coresight-cpu-debug 850000.debug:  EDPCSR:  [<ffff00000808e9bc>] handle_IPI+0x174/0x1d8
+coresight-cpu-debug 850000.debug:  EDCIDSR: 00000000
+coresight-cpu-debug 850000.debug:  EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0)
+coresight-cpu-debug 852000.debug: CPU[1]:
+coresight-cpu-debug 852000.debug:  EDPRSR:  00000001 (Power:On DLK:Unlock)
+coresight-cpu-debug 852000.debug:  EDPCSR:  [<ffff0000087fab34>] debug_notifier_call+0x23c/0x358
+coresight-cpu-debug 852000.debug:  EDCIDSR: 00000000
+coresight-cpu-debug 852000.debug:  EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0)