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

The callback structure is used exclusively for reading or writing
therefore there is no reason to hold both response and request buffers
in the callback structure
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On memory allocation failure mei_cl_irq_read_msg will
return with error that will cause device reset.
Instead we should propagate error to caller and
just clean the read queues.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

To support dynamic addition and removal of
me clients we add reference counter.

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

Mei bus receive and send function may return either number
of transmitted bytes or errno.  It is better to use ssize_t
type for that purpose that mixing size_t with int.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

NFC internal structure cleaning was dropped by commit

commit 48705693
Author: Tomas Winkler <tomas.winkler@intel.com>
Date:   Mon Feb 17 15:13:19 2014 +0200

    mei: Remove all bus devices from the mei_dev list when stopping the MEI

    When stopping the MEI, we should remove and potentially unregister
    all bus devices queued on the mei_dev linked list.

We allocate nfc_dev and free it across the reset
so we do not keep it in dirty state
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>

Remove inclusion of linux/pci.h in mei layer
however we need to include the headers that before
got included implicitly from linux/pci.h.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

For purpose of adding testing HW we would like
to get rid of pci dependency in generic mei code
This patch provides only straight forward changes
FW status and prob quirks need to be handled separately
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

function 'strncpy' will fill whole buffer 'id.name' of fixed size (32)
with string value and will not leave place for NULL-terminator.
Possible buffer boundaries violation in following string operations.
Replace strncpy with strlcpy.

Cc: stable@vger.kernel.org # 3.10+
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>

When handling dynamic clients there might be a race
scenario in which two me clients with the same me
address would be linked in the me clients list,
therefore we need to search by both uuid and me address.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

For support of dynamic addition and removal of me clients
it is more convenient to use a list instead of static array
as is use now.
As the first step of the transition to the new data structure
we change the lookup function so it returns me client address
instead of an index.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Adding power gating introduced new waiting state for client also during
connection attempt, a connection request can be queued for later either due
device is power gated or due to other on going connection.
We setting client connection state before start of full connect procedure so
in both cased the client state will be MEI_FILE_CONNECTING
which create interlock between the two connection attempts, both
detecting that another connection is in progress.

The interlock is resolved by moving client to connecting state
only upon connection request transmission, so the  first
cb in queue can be processed.
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>

Follow-up for bits missed in
commit 7ca96aa2
mei: make return values consistent across the driver
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 includes of me-hw.h and me-hw-regs.h headers from
the mei generic code.
The mei layer should not depend on hw specific headers
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We can use simply list_for_each_entry if there is no
entry removal
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When stopping the MEI, we should remove and potentially unregister
all bus devices queued on the mei_dev linked list.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

no need to change error code value returned by
mei_me_cl_by_id, just propagate it on
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Bus layer omitted check for client state transition while waiting
for read completion
The client state transition may occur for example as result
of firmware initiated reset

Add mei_cl_is_transitioning wrapper to reduce the code
repetition.:

Cc:  <stable@vger.kernel.org> # 3.9+
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead.  This converts the MEI bus code to use
the correct field.
Acked-by: NTomas Winkler <tomas.winkler@intel.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

1. use strncmp for comparsion strncpy was used for copying
which may omit the final %NUL terminator
2. id->name is statically defined so we can use sizeof
Acked-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

After cancelling all reads from the disable hook, we need to reset the
event_cb pointer as well or else we won't be able to set a new one up
when re-enabling the device.
Acked-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

While writting to device is limitted to max_msg_length advertized
in client properites the read can be much longer delivered consequiting chunks.

We use krealloc to enlarge the buffer when needed.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It should be left to the drivers to enable and disable the device on the
MEI bus when e.g getting probed.
For drivers to be able to safely call the enable and disable hooks, the
mei_cl_ops must be set before it's probed and thus this should happen
before registering the device on the MEI bus. Hence the mei_cl_add_device()
prototype change.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

consolidate write code to a specific me client in mei_cl_write function
the function is called from mei device write handler and from
mei_cl bus send function
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

MEI drivers should be able to carry their private data around.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Define a truly synchronous API for the bus Tx path by putting all pending
request to the write list and wait for the interrupt tx handler to wake
us up.
The ___mei_cl_send() out path is also slightly reworked to make it look more
like main.c:mei_write().
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Register the MEI bus type against the kernel core bus APIs and
call the bus Rx handler from interrupt.c
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We keep track of all MEI devices on the bus through a specific linked list.
We also have a mei_device instance in the mei_cl structure.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

mei client bus will present some of the mei clients
as devices for other standard subsystems

Implement the probe, remove, match, device addtion routines, along with
the sysfs and uevent ones. mei_cl_device_id is also added to
mod_devicetable.h
A mei-cleint-bus.txt document describing the rationale and the API usage
is also added while ABI/testing/sysfs-bus-mei describeis the modalias ABI.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>