mei: prevent queuing new flow control credit.

The MEI FW can receive only one flow control for read.
Currently the driver only checks if a flow control credit was already
sent and r

mei: prevent queuing new flow control credit.

The MEI FW can receive only one flow control for read.
Currently the driver only checks if a flow control credit was already
sent and read is pending in the rd_pending queue, but it also has to
check if flow control credit already queued in the write control queue
to prevent sending more than one flow control credits.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: remove check on pm_runtime_active in __mei_cl_disconnect

Remove bogus check on pm_runtime_active that prevented
disconnection from a client in case the device was resuming
from

mei: remove check on pm_runtime_active in __mei_cl_disconnect

Remove bogus check on pm_runtime_active that prevented
disconnection from a client in case the device was resuming
from power gating but not yet active.

Fix regression introduced by
18901357e70ae29e3fd1c58712a6847c2ae52eae
mei: disconnect on connection request timeout

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: bus: add and call callback on notify event

Enable drivers on mei client bus to subscribe
to asynchronous event notifications.
Introduce events_mask to the existing callback infr

mei: bus: add and call callback on notify event

Enable drivers on mei client bus to subscribe
to asynchronous event notifications.
Introduce events_mask to the existing callback infrastructure
so it is possible to handle both RX and event notification.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: implement fasync for event notification

A process can be informed about client notification also via
SIGIO with POLL_PRI event.

Signed-off-by: Tomas Winkler <tomas.winkler@

mei: implement fasync for event notification

A process can be informed about client notification also via
SIGIO with POLL_PRI event.

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

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mei: add a handler that waits for notification on event

mei_cl_notify_get is to be called by a host client
to wait, receive, and ack the event notification.

Signed-off-by: Tomas

mei: add a handler that waits for notification on event

mei_cl_notify_get is to be called by a host client
to wait, receive, and ack the event notification.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: add mei_cl_notify_request command

Add per client notification request infrastructure
that allows client to enable or disable async
event notification.

Signed-off-by: To

mei: add mei_cl_notify_request command

Add per client notification request infrastructure
that allows client to enable or disable async
event notification.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: disconnect on connection request timeout

For the FW with HBM version >= 2.0 we don't need to reset the whole
device in case of a particular client failing to connect, it is enough

mei: disconnect on connection request timeout

For the FW with HBM version >= 2.0 we don't need to reset the whole
device in case of a particular client failing to connect, it is enough
to send disconnect a request to bring the device to the stable state.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: bus: link client devices instead of host clients

MEI bus was designed around nfc and was hard to extend.
Instead of the hard coded way of adding the devices on the mei bus
we sc

mei: bus: link client devices instead of host clients

MEI bus was designed around nfc and was hard to extend.
Instead of the hard coded way of adding the devices on the mei bus
we scan the whole me client list and create a device for each
eligible me client (mei_cl_bus_rescan); currently we support
only clients with single connection and fixed address clients.
NFC radio name detection is run as a fixup routine

The patch replaces handling the device list based on struct me_cl
to device list based on me_cl_devices. The creating a connection
is pushed from the device creation time to device enablement.

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

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mei: do not access freed cb in blocking write

The mei_cl_write function is giving up on a write cb ownership after it
was sent or queued. The write cb is then freed in the completion

mei: do not access freed cb in blocking write

The mei_cl_write function is giving up on a write cb ownership after it
was sent or queued. The write cb is then freed in the completion
handler. Especially during blocking write mei_cl_write function waits
for the completion handler and then access the freed memory to fetch the
written size. The quick fix is to store the buffer size prior to
sending, the size is not altered during the flow.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: me: wait for power gating exit confirmation

Fix the hbm power gating state machine so it will wait till it receives
confirmation interrupt for the PG_ISOLATION_EXIT message.

mei: me: wait for power gating exit confirmation

Fix the hbm power gating state machine so it will wait till it receives
confirmation interrupt for the PG_ISOLATION_EXIT message.

In process of the suspend flow the devices first have to exit from the
power gating state (runtime pm resume).
If we do not handle the confirmation interrupt after sending
PG_ISOLATION_EXIT message, we may receive it already after the suspend
flow has changed the device state and interrupt will be interpreted as a
spurious event, consequently link reset will be invoked which will
prevent the device from completing the suspend flow

kernel: [6603] mei_reset:136: mei_me 0000:00:16.0: powering down: end of reset
kernel: [476] mei_me_irq_thread_handler:643: mei_me 0000:00:16.0: function called after ISR to handle the interrupt processing.
kernel: mei_me 0000:00:16.0: FW not ready: resetting

Cc: <stable@vger.kernel.org> #3.18+
Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=86241
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=770397
Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: reset flow control on the last client disconnection

The FW resets the flow control for single buffer clients when the last
host client disconnects, also the driver has to follow thi

mei: reset flow control on the last client disconnection

The FW resets the flow control for single buffer clients when the last
host client disconnects, also the driver has to follow this policy and
zero the flow control counter in such case.

Cc: <stable@vger.kernel.org> #4.1
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: request autosuspend at the end of write

On longer non-blocking write might not complete at the end of
autosuspend expiration, therefore we request autosuspend
again on the write

mei: request autosuspend at the end of write

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: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: consume flow control on the first chunk of writing

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

mei: consume flow control on the first chunk of writing

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: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: support for fixed address clients

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 f

mei: support for fixed address clients

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: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: fix flow control for single buffer clients

For ME clients that use single receiving buffer
the driver tracks credentials on mei_me_clients structure
for all connections. The dri

mei: fix flow control for single buffer clients

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: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: add a reference from the host client to the me client

Keep a pointer to associated me client in the host client object to
eliminate me client searches. Check if the me client is act

mei: add a reference from the host client to the me client

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: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: revamp client connection

Simplify connect state machine by changing the logic around
Connection request in progress - only check if we have a callback in
relevant queue.
Ext

mei: revamp client connection

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: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: revamp client disconnection flow

Split disconnected state into two parts first reception disconnect
response from the firmware and second actually setting of disconnected
state.

mei: revamp client disconnection flow

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: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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mei: use mei_cl_is_connected consistently

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

Note that cl->state != MEI_FILE_CONN

mei: use mei_cl_is_connected consistently

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

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mei: fix mei_poll operation

mei_poll returned with POLLIN w/o checking whether the operation
has really completed.
remove redundant check and locking in amthif specific handler

mei: fix mei_poll operation

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

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mei: free me client references on host init

Fx fixes leak introduced by:
commit b7d885145538 ("mei: revamp me clients list handling")

Signed-off-by: Tomas Winkler <tomas.winkler

mei: free me client references on host init

Fx fixes leak introduced by:
commit b7d885145538 ("mei: revamp me clients list handling")

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

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mei: allow read concurrency

Replace clunky read state machine with read stack
implemented as per client read list, this is important
mostly for mei drivers with unsolicited reads

mei: allow read concurrency

Replace clunky read state machine with read stack
implemented as per client read list, this is important
mostly for mei drivers with unsolicited reads

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

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mei: simplify io callback disposal

Simplify disposal of io callback by removing the callback
implicitly from its lookup list inside mei_io_cb_free

Signed-off-by: Tomas Winkler <

mei: simplify io callback disposal

Simplify disposal of io callback by removing the callback
implicitly from its lookup list inside mei_io_cb_free

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

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mei: add mei_cl_alloc_linked function

Add convenient wrapper mei_cl_alloc_linked
to simplify error handling

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off

mei: add mei_cl_alloc_linked function

Add convenient wrapper mei_cl_alloc_linked
to simplify error handling

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

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mei: always initialize the callback with the intended operation type

We set the operation type at initialization time as each cb is used only
for a single type of operation

As a

mei: always initialize the callback with the intended operation type

We set the operation type at initialization time as each cb is used only
for a single type of operation

As a byproduct we add a convenient wrapper for allocating cb with
the data buffer.

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

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