commit c45e3e4c5b134b081e8af362109905427967eb19 upstream.

A recent change fixing NFC device allocation itself introduced an
error-handling bug by returning an error pointer in case device-id
allocation failed. This is clearly broken as the callers still expected
NULL to be returned on errors as detected by Dan's static checker.

Fix this up by returning NULL in the event that we've run out of memory
when allocating a new device id.

Note that the offending commit is marked for stable (3.8) so this fix
needs to be backported along with it.

Fixes: 20777bc57c34 ("NFC: fix broken device allocation")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 20777bc57c346b6994f465e0d8261a7fbf213a09 upstream.

Commit 7eda8b8e9677 ("NFC: Use IDR library to assing NFC devices IDs")
moved device-id allocation and struct-device initialisation from
nfc_allocate_device() to nfc_register_device().

This broke just about every nfc-device-registration error path, which
continue to call nfc_free_device() that tries to put the device
reference of the now uninitialised (but zeroed) struct device:

kobject: '(null)' (ce316420): is not initialized, yet kobject_put() is being called.

The late struct-device initialisation also meant that various work
queues whose names are derived from the nfc device name were also
misnamed:

  421 root         0 SW<  [(null)_nci_cmd_]
  422 root         0 SW<  [(null)_nci_rx_w]
  423 root         0 SW<  [(null)_nci_tx_w]

Move the id-allocation and struct-device initialisation back to
nfc_allocate_device() and fix up the single call site which did not use
nfc_free_device() in its error path.

Fixes: 7eda8b8e9677 ("NFC: Use IDR library to assing NFC devices IDs")
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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>

NFC_EVT_TRANSACTION is sent through netlink in order for a
specific application running on a secure element to notify
userspace of an event. Typically the secure element application
counterpart on the host could interpret that event and act
upon it.

Forwarded information contains:
- SE host generating the event
- Application IDentifier doing the operation
- Applications parameters

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

Remove one useless blank line at beginning of nfc_disable_se function.

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

Remove one useless blank line at beginning of nfc_enable_se function.

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

This checking is common for all caller, so move the checking to one place.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

Without this test, it returns NULL if dev->n_targets is 0 anyway.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

nfc_find_se() does not modify any list entry while iterating the list.
So use list_for_each_entry instead of list_for_each_entry_safe.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>