With this patch, the Digital Protocol layer abort the last issued
command when the dep link goes down. That way it does not have to wait
for the driver to reply with a timeout error before sending a new
command (i.e. a start poll command if constant polling is on).

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

There is a flag in the command structure indicating that this command is
pending. It was checked before sending the command to not send the same
command twice but it was actually never set. This is now fixed.

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

With this patch, when freeing the command queue in the module unregister
function, the callbacks of the commands still queued are called with a
ENODEV error. This gives a chance to the command issuer to free any
memory it could have allocate.

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

This replaces the polling work struct with a delayed work struct and add
a 10 ms delay between 2 poll cycles. This avoids to flood the device
with 'switch off'/'switch on' commands.

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

The definition of DIGITAL_PROTO_NFCA_RF_TECH is modified to support
ISO14443 Type4A tags. Without this change it is not possible to start
polling for ISO14443 Type4A tags from the initiator side.

Signed-off-by: Shikha Singh <shikha.singh@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

In order to manage in a better way the nci poll mode state machine,
add mode parameter to deactivate_target functions.
This way we can manage different target state.
mode parameter make sense only in nci core.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

The digital layer of the NFC subsystem currently
supports a 'tg_listen_mdaa' driver hook that supports
devices that can do mode detection and automatic
anticollision.  However, there are some devices that
can do mode detection but not automatic anitcollision
so add the 'tg_listen_md' hook to support those devices.

In order for the digital layer to get the RF technology
detected by the device from the driver, add the
'tg_get_rf_tech' hook.  It is only valid to call this
hook immediately after a successful call to 'tg_listen_md'.

CC: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

Currently, digital_target_found() has a race between
the events started by calling nfc_targets_found()
(which ultimately expect ddev->poll_tech_count to be
zero) and setting ddev->poll_tech_count to zero after
the call to nfc_targets_found().  When the race is
"lost" (i.e., ddev->poll_tech_count is found to not
be zero by the events started by nfc_targets_found()),
an error message is printed and the target is not found.
A similar race exists when digital_tg_recv_atr_req()
calls nfc_tm_activated().

Fix this by first saving the current value of
ddev->poll_tech_count and then clearing it before
calling nfc_targets_found()/nfc_tm_activated().
Clearing ddev->poll_tech_count before calling
nfc_targets_found()/nfc_tm_activated() eliminates
the race.  Saving the value is required so it can be
restored when nfc_targets_found()/nfc_tm_activated()
fails and polling needs to continue.

Acked-by: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

This change adds some entropy to polling cycles, choosing the next
polling rf technology randomly. This reflects the change done in the
pn533 driver, avoiding possible infinite loop for devices that export 2
targets on 2 different modulations. If the first target is not
readable, we will stay in an error loop for ever.

Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

Add support for the ISO/IEC 14443-B protocol and Type 4B tags.
It is expected that there will be only one tag within range so the full
anticollision scheme is not implemented. Only the SENSB_REQ/SENSB_RES
and ATTRIB_REQ/ATTRIB_RES are implemented.

CC: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>