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
  ...
This commit is contained in:
Linus Torvalds
2017-07-03 20:55:59 -07:00
167 changed files with 12820 additions and 1631 deletions
+38
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@@ -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.
@@ -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.
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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.
+9 -9
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@@ -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>
+3 -1
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@@ -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)
+1
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@@ -61,6 +61,7 @@ configure specific aspects of kernel behavior to your liking.
java
ras
pm/index
thunderbolt
.. only:: subproject and html
@@ -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
+199
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@@ -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.
@@ -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>;
};
@@ -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>;
}
@@ -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>;
};
};
};
@@ -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";
};
@@ -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";
};
@@ -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 {
/* ... */
};
};
};
@@ -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>;
};
};
};
@@ -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>;
};
@@ -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
+6 -1
View File
@@ -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()
+175
View File
@@ -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)
+22
View File
@@ -1207,7 +1207,9 @@ L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
S: Maintained
F: drivers/hwtracing/coresight/*
F: Documentation/trace/coresight.txt
F: Documentation/trace/coresight-cpu-debug.txt
F: Documentation/devicetree/bindings/arm/coresight.txt
F: Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt
F: Documentation/ABI/testing/sysfs-bus-coresight-devices-*
F: tools/perf/arch/arm/util/pmu.c
F: tools/perf/arch/arm/util/auxtrace.c
@@ -6489,6 +6491,13 @@ F: Documentation/ABI/testing/sysfs-bus-iio-adc-envelope-detector
F: Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
F: drivers/iio/adc/envelope-detector.c
IIO MULTIPLEXER
M: Peter Rosin <peda@axentia.se>
L: linux-iio@vger.kernel.org
S: Maintained
F: Documentation/devicetree/bindings/iio/multiplexer/iio-mux.txt
F: drivers/iio/multiplexer/iio-mux.c
IIO SUBSYSTEM AND DRIVERS
M: Jonathan Cameron <jic23@kernel.org>
R: Hartmut Knaack <knaack.h@gmx.de>
@@ -8724,6 +8733,15 @@ S: Orphan
F: drivers/mmc/host/mmc_spi.c
F: include/linux/spi/mmc_spi.h
MULTIPLEXER SUBSYSTEM
M: Peter Rosin <peda@axentia.se>
S: Maintained
F: Documentation/ABI/testing/mux/sysfs-class-mux*
F: Documentation/devicetree/bindings/mux/
F: include/linux/dt-bindings/mux/
F: include/linux/mux/
F: drivers/mux/
MULTISOUND SOUND DRIVER
M: Andrew Veliath <andrewtv@usa.net>
S: Maintained
@@ -11336,6 +11354,9 @@ F: Documentation/tee.txt
THUNDERBOLT DRIVER
M: Andreas Noever <andreas.noever@gmail.com>
M: Michael Jamet <michael.jamet@intel.com>
M: Mika Westerberg <mika.westerberg@linux.intel.com>
M: Yehezkel Bernat <yehezkel.bernat@intel.com>
S: Maintained
F: drivers/thunderbolt/
@@ -13789,6 +13810,7 @@ M: Evgeniy Polyakov <zbr@ioremap.net>
S: Maintained
F: Documentation/w1/
F: drivers/w1/
F: include/linux/w1.h
W83791D HARDWARE MONITORING DRIVER
M: Marc Hulsman <m.hulsman@tudelft.nl>

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