skb is already freed in st21nfca_tx_work and was freed also in
st21nfca_im_send_psl_req.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

"skb" can be NULL here but it can't be an ERR_PTR:
- IS_ERR(NULL) return false and skb migth be NULL.
- skb cannot be a ERR_PTR as nfc_hci_send_cmd_async it never using such cast.

!skb is more appropriate at those places.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

In case we are not able to read out the NDLC/NCI header, we do not
consider this as an issue and we will give a later chance.
The NDLC layer will handle errors thanks to its internal timers.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Add support for ISO/IEC 15693 RF technology and Type 5 tags.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

In NFC Forum NCI specification, some RF Protocol values are
reserved for proprietary use (from 0x80 to 0xfe).
Some CLF vendor may need to use one value within this range
for specific technology.
Furthermore, some CLF may not becompliant with NFC Froum NCI
specification 2.0 and therefore will not support RF Protocol
value 0x06 for PROTOCOL_T5T as mention in a draft specification
and in a recent push.

Adding get_rf_protocol handle to the nci_ops structure will
help to set the correct technology to target.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

T2 was never started when sending a command.
Start it when sending a command for the first attempt
and stop it once we receive the answer.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

On st21nfcb the irq line might be kept to active state because of other
interfaces activity. This may generate i2c read tentative resulting in
i2c NACK.

This fix will currently let NDLC upper layer to decide when it is relevent
to signal to the physical layer when the chip as muted.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

St21nfcb has a reverse polarity compare to st21nfca.
In st21nfcb case, the irq pin is active high.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This patch fix a previous patch introduce by commit	0a91e8ac

It is actually fixing a double free mistake in all st21nfca_tm_* function.
We decide to return directly in case of successful execution because skb
got already freed. In st21nfca_tm_recv_dep_req it got freed by nfc_tm_data_received.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

After a unsuccessful call to nfc_hci_send_event the skb was not
freed and might lead to memory leak.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Fix few conding style issue such as useless line return or tab.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The recently added _trf7970a_tg_listen() routine
has some return paths that don't unlock the mutex
that is locked when the routine is entered.  Fix
this by always unlocking the mutex before returning.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Recent changes to trf7970a_irq() added a couple return
paths that don't unlock the mutex that is locked when
the routine is entered.  Fix this by ensuring the mutex
is always unlocked before returning.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

There is no need to initialize the 'ret' variable
in trf7970a_resume().
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The trf7970a_suspend() routine always returns
zero so don't use a local return variable to
hold the return value.  This fixes up a smatch
warning.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Remove some headers as they are:
- not relevent for st21nfcb.
- called multiple times for no reason: example st21nfcb.h already include
ndlc.h.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

scripts/checkpatch.pl -f drivers/nfc/st21nfca.c is throwing the following:
WARNING: else is not generally useful after a break or return
#866: FILE: drivers/nfc/st21nfca/st21nfca.c:866:
+			return 0;
+		} else {
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Align every macros on the same column.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Clean up st21nfca.h macros and move the one only used in st21nfca.c.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

When retrying to read the NCI header, the CLF might not be
available the first time. However it may not be successful
the second time and this may cause an error in the function.
Enforce the retrieve data length is as expected.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

gb_len in st21nfca_tm_send_atr_res can be negative. Not checking for
that could lead to a potential kernel oops.
We now make sure that atr_req->length > sizeof(struct st21nfca_atr_req)
to avoid such situation.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

skb is already verified to be not null from the below hci layer.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

On top of st21nfca_im_recv_atr_res_cb and st21nfca_im_recv_dep_res_cb a
condition if (err != 0) is present. Because err is never modified in the
code err will always be 0 at the end.

The condition can be removed.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

nfcid3 is based on sensf_res value. target->sensf is never NULL
as it is a table.
Check the sensf_res_len instead to make sure sensf_res is set or not.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Remove a useless new line in nfc_err call.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

If dev_num >= ST21NFCA_NUM_DEVICES, the driver was returning an incorrect
success return code.

Once dev_num is set, it was not stated as busy.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

In case of an error during driver probe, info pointer was freed with kfree.
No need to free anything when using devm_kzalloc.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Remove a uselss new line in nfc_err call.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The .owner member of struct device_driver is assigned THIS_MODULE twice.

Introduced by:

commit 35630df6
NFC: st21nfcb: Add driver for STMicroelectronics ST21NFCB NFC chip
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Simplify the code a bit as mention by Axel Lin in a previous patch for
st21nfca.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Fixing scripts/checkpatch.pl error "code indent should use tabs where possible" in:
- i2c.c in st21nfcb_nci_irq_thread_fn function.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Fixing scripts/checkpatch.pl warning "Missing a blank line after declarations" in:
- st21nfca.c:
	- check_presence after fwi variable declaration.
	- get_frame_size after len variable declaration.
	- st21nfca_hci_i2c_repack after "i, j, r, size" variable declaration.

- st21nfca_dep.c st21nfca_tx_work after skb pointer declaration.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Fixing "sparse: cast to restricted __be32" message when building with
make C=1 CF=-D__CHECK_ENDIAN__
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This simplifies the code a bit.
Acked-by: NChristophe RICARD <christophe-h.ricard@st.com>
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The .owner member of struct device_driver is assigned THIS_MODULE twice.

Introduced by:

commit c44cb2ed
("NFC: dts: st21nfca: Add device-tree (Open Firmware) support to st21nfca")
Acked-by: NChristophe RICARD <christophe-h.ricard@st.com>
Signed-off-by: NEmil Goode <emilgoode@gmail.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Add the ability to detect the mode (i.e., RF technology)
used by the initiator.  The RF technology that was
detected can be retrieved by calling the 'tg_get_rf_tech'
driver hook.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Add target mode support to the trf7970a
NFC driver.  This effectively enables full
Peer-to-Peer support.

To handle changing framing between sending
a response frame and receiving the subsequent
request frame, most of the framing changes
take effect in the interrupt handler and not
in trf7970a_tg_config_framing().
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The digital layer can try to send a command with a
timeout value of zero (e.g., digital_tg_send_psl_res().
The zero value is used as a flag to indicate that
the driver should not expect a response.  To handle
this, the driver sets an internal timer because it
should still get an interrupt with the TX bit set
in the IRQ Status Register.  When it gets that
interrupt, it returns a return value of '0'.
If it doesn't get the interrupt before timing out,
it returns ETIMEDOUT as usual.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Some paths leave a timer still running when
trf7970a_send_err_upstream() is called.  This
can cause a timeout to occur in a subsequent
transaction making it fail.  Fix this by ensuring
there is no timer running before sending an error
upstream.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Currently, the trf7970a driver blindly turns on its
RF field when configuring its framing.  This isn't
a good idea if there is already a device generating
an RF field.  Instead, check if there is already an
RF field present before turning on this device's RF
field and, if there is, return EBUSY.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>