static analysis with smatch picked up the following error:

get_platform_data() error: potential null dereference 'dt_pdata'.
  (kzalloc returns null)

Instead, the code should return NULL to avoid the following null
pointer deference.  Also, remove the error message as it is
redundant, the caller emits an error message to alert of a
failure anyhow.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

MIC card driver specific changes to enable SCIF. This patch implements
the SCIF hardware bus operations and registers a SCIF device on the
SCIF hardware bus.
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Signed-off-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

MIC host driver specific changes to enable SCIF. This patch implements
the SCIF hardware bus operations and registers a SCIF device on the
SCIF hardware bus.
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SCIF messaging APIs which allow sending messages between the SCIF
endpoints via a byte stream based ring buffer which has been
optimized to avoid reads across PCIe. The SCIF messaging APIs
are typically used for short < 1024 byte messages for best
performance while the RDMA APIs which will be submitted in a future
patch series is recommended for larger transfers. The node
enumeration API enables a user to query for the number of nodes
online in the SCIF network and their node ids.
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NNikhil Rao <nikhil.rao@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SCIF connection APIs which establish a SCIF connection between
a pair of SCIF endpoints. A SCIF connection consists of a
dedicated queue-pair between the endpoints. Client messages are
sent over the queue-pair whereas the signaling associated with the
message is multiplexed over the node queue-pair. Similarly other
control messages such as exposing registered memory are also sent
over the node queue-pair. The SCIF endpoints must be in connected
state to exchange messages, register memory, map remote memory and
trigger DMA transfers. SCIF connections can be set up
asynchronously or synchronously.

Thanks to Johnnie S Peters for authoring parts of this patch during
early bring up of the SCIF driver.
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NNikhil Rao <nikhil.rao@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SCIF character device file operations and kernel APIs for opening and
closing a user and kernel mode SCIF endpoint. This patch also enables
binding to a SCIF port and listening for incoming SCIF connections.
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SCIF node queue pair setup creates the SCIF driver kernel
mode private node queue pairs between all the nodes to enable
internal control message communication once SCIF gets probed
by the SCIF hardware bus. Peer to peer communication between
MIC Coprocessor nodes is supported.
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SCIF module initialization, DMA mapping, ioremap wrapper APIs
and debugfs hooks. SCIF gets probed by the SCIF hardware bus
if SCIF devices were registered by base drivers. A MISC device
is registered to provide the SCIF character device interface.
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Update mic_bootparam and define the maximum number of DMA channels
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The SCIF peer bus is used to register and unregister SCIF peer devices
internally by the SCIF driver to signify the addition and removal of
peer nodes respectively from the SCIF network. This simplifies remote node
handling within SCIF and will also be used to support device probe/remove
for SCIF client drivers (e.g. netdev over SCIF)
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The SCIF hardware bus abstracts the low level hardware driver details
like interrupts and mapping remote memory so that the same SCIF driver
can work without any changes with the MIC host or card driver as long
as the hardware bus operations are implemented. The SCIF hardware
device is registered by the host and card drivers on the SCIF hardware
bus resulting in probing the SCIF driver.
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SCIF ring buffer is a single producer, single consumer byte stream
ring buffer optimized for avoiding reads across the PCIe bus while
adding the required barriers and hardware workarounds for the MIC
Coprocessor. The ring buffer is used to implement a receive queue for
SCIF driver messaging between two nodes and for byte stream messaging
between SCIF endpoints. The existing in-kernel ring buffer was not
reused since it has not been designed for our use across the PCIe bus
where each node runs an independent OS. Each SCIF node has a receive
queue for every other SCIF node, and each connected endpoint has a
receive queue for messages from its peer. This pair of receive
queues is referred to as a SCIF queue pair.
Reviewed-by: NNikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The CARMA project has ended, and the hardware has all been moved into
storage. It is unlikely to ever be used again.

Remove the drivers so that there is no more maintenance burden from
ongoing upstream kernel changes.
Signed-off-by: NIra W. Snyder <ira.snyder@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

since we move all nfc hanling to the mei_phy module
we can kill mei_cl_ops

Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

move nfc logic to mei_phy module, we prefer as much as
possible not to deal with a particualr client protocol
in the mei generic infrasutcutre

Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Export name and uuid via sysfs and uevent

Cc: linux-api@vger.kernel.org
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In order to automate modules matching add device uuid
which is reported in client enumeration, keep also
the name that is needed in for nfc distinguishing radio vendor

Report mei:name:uuid

Cc: linux-api@vger.kernel.org
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The io callback is clear from write_waitling_list after
we receive interrupt from the hw to ack the write completion.
We need to wait for this interrupt deliver before we try
to enter low power state
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On longer non-blocking write might not complete at the end of
autosuspend expiration, therefore we request autosuspend
again on the write completion.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Consume the write flow control on the first chunk of the write instead
of on the buffer completion.
We can safely assume that the consequent chunks have the flow control
granted.

This addresses two issues:

1. Blocks other callbacks from the same client riding on the client's
flow control and prevents interleaving of messages as FW cannot distinguish
between two messages from the same client.

2. Fixes single buffer flow control arbitration in a clean way, without
connection/disconnection book keeping
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add client info to debug prints in the read function to
ease on debugging efforts.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove spurious blank
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We can receive mtu with one call now, no need to store it.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This should be used for debug only.
The feaure is gated by "allow_fixed_address" control exposed in debugfs.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fixed address is simplified FW client that doesn't require
connection and doesn't support flow control.
So it can be only one host client per fixed FW client.
Fixed client access is available only for drivers on mei bus,
connection from user-space is blocked.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

For ME clients that use single receiving buffer
the driver tracks credentials on mei_me_clients structure
for all connections. The driver needs to book keep the shared
resource correctly and track the connections, particularly
the credit has to be cleaned when there is no active connection
to a particular me client. This solves issue when subsequent
connection will not get an ill impression that it can write.

We add active connection counter the particular ME client and
when the counter reach zero, we clear the credits.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Keep a pointer to associated me client in the host client object to
eliminate me client searches. Check if the me client is active in the
firmware by checking if its is linked on the me clients list
Add accessors for the me client properties from host client.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Simplify connect state machine by changing the logic around
Connection request in progress - only check if we have a callback in
relevant queue.
Extract common code into mei_cl_send_connect() function
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Split disconnected state into two parts first reception disconnect
response from the firmware and second actually setting of disconnected
state.  Book keeping data are needed for processing and after firmware
disconnected the client and are cleaned when setting the disconnected
state in mei_cl_set_disconneted() function.
Add mei_cl_send_disconnect to reduce code duplication.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

HW has to be in known state before the initialisation
sequence is started. The polling step for settling aliveness
was set to 200ms while in practise this can be done in up to 30msecs.

Cc: <stable@vger.kernel.org> #3.18+
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NBarak Yoresh <barak.yoresh@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

fix warning:
include/trace/ftrace.h:28:0: note: this is the location of the previous definition
 ^
In file included from include/trace/define_trace.h:90:0,
                 from drivers/misc/mei/mei-trace.h:76,
                 from drivers/misc/mei/mei-trace.c:21:
include/trace/ftrace.h:28:0: warning: "TRACE_SYSTEM_STRING" redefined

Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds support for the the wakeup threshold and
support for the second wakeup unit to the DT based
setup.
Signed-off-by: NSebastian Reichel <sre@kernel.org>
Reviewed-by: NÉric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

st,axis-{x,y,z} can be negative to imply inverted
axis.

Apart from that the minimal and maximal threshold
may be negative.
Signed-off-by: NSebastian Reichel <sre@kernel.org>
Reviewed-by: NÉric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The function mei_cl_is_transitioning is just opposite
of mei_cl_is_connected. What we actually wanted to
check is if we lost connection so we can discard
the check for transition and check for 'not connected'
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Replace open coded check for cl->state !=/== MEI_FILE_CONNECTED
with mei_cl_is_connected function.

Note that cl->state != MEI_FILE_CONNECTED is not the same
as cl->state == MEI_FILE_DISCONNECTED
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

mei_poll returned with POLLIN w/o checking whether the operation
has really completed.
remove redundant check and locking in amthif specific handler
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

pci core now disables msi on probe automatically,
drop this from device-specific code.

Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We have peculiar problems with multi-path and enclosures: physically, we know
each bay can only be occupied by a single disk device.  However in multi-path,
it appears we have many (because each path to the device appears in Linux as a
different kernel device).  We try to fix this by only having the last seen
device show up in the bay.

Sysfs gets very annoyed if we try to manipulate links when the kobject sysfs
directory (kobj.sd) doesn't exist and drops a huge WARN_ON which most users
panic and report an oops for.  This happens on a few path removal situations
and IBM reports seeing it when one of their multi-path adapters is removed.

Add a check to enclosure device removal for the existence the sysfs directory
containing both the forward and back links so that the remnants (if any) get
removed in either direction but no scary warnings are dumped.
Reported-by: NWen Xiong <wenxiong@linux.vnet.ibm.com>
Tested-by: NWen Xiong <wenxiong@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>