This patch allows to simulate the lost of frames exchanged between the 2
nfcsim devices through a control entry in the debugfs and is used as
follow:
echo n > /sys/kernel/debug/nfcsim/nfcX/dropframe
Where n specifies the number of frames to be dropped between 0 and 255
and nfcX is either nfc0 or nfc1, one of the two nfcsim devices.
In the following example, the next frame that should be sent by the nfc0
device will be dropped and thus not received by the nfc1 device:
echo 1 > /sys/kernel/debug/nfcsim/nfc0/dropframe
The value of 0 can be used to reset the dropframe counter.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The idea is to have a way to control and/or modify the behavior of the
nfcsim virtual devices.
This patch creates a folder tree in the debug filesystem. The debugfs is
usually mounted into /sys/kernel/debug and the nfcsim entries are
located in DEBUGFS/nfcsim/nfcX/ where X is either 0 or 1 depending on
the device you want to address.
These folders are empty for now and control entries will be added by
upcoming commits.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When the target needs more time to process the received PDU, it sends
Response Timeout Extension (RTOX) PDU.
When the initiator receives a RTOX PDU, it must reply with a RTOX PDU
and extends the current rwt value with the formula:
rwt_int = rwt * rtox
This patch takes care of the rtox value passed by the target in the RTOX
PDU and extends the timeout for the next response accordingly.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When sending an ATR_REQ, the initiator must wait for the ATR_RES at
least 'RWT(nfcdep,activation) + dRWT(nfcdep)' and no more than
'RWT(nfcdep,activation) + dRWT(nfcdep) + dT(nfcdep,initiator)'. This
gives a timeout value between 1237 ms and 1337 ms. This patch defines
DIGITAL_ATR_RES_RWT to 1337 used for the timeout value of ATR_REQ
command.
For other DEP PDUs, the initiator must wait between 'RWT + dRWT(nfcdep)'
and 'RWT + dRWT(nfcdep) + dT(nfcdep,initiator)' where RWT is given by
the following formula: '(256 * 16 / f(c)) * 2^wt' where wt is the value
of the TO field in the ATR_RES response and is in the range between 0
and 14. This patch declares a mapping table for wt values and gives RWT
max values between 100 ms and 5049 ms.
This patch also defines DIGITAL_ATR_RES_TO_WT, the maximum wt value in
target mode, to 8.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This patch frees the RTOX resp sk_buff in initiator mode. It also makes
use of the free_resp exit point for ATN supervisor PDUs in both
initiator and target mode.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
With this patch, ACK PDU sk_buffs are now freed and code has been
refactored for better errors handling.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When the target receives a NACK PDU, it re-sends the last sent PDU.
ACK PDUs are received by the target as a reply from the initiator to
chained I-PDUs. There are 3 cases to handle:
- If the target has previously received 1 or more ATN PDUs and the PNI
in the ACK PDU is equal to the target PNI - 1, then it means that the
initiator did not received the last issued PDU from the target. In
this case it re-sends this PDU.
- If the target has received 1 or more ATN PDUs but the ACK PNI is not
the target PNI - 1, then this means that this ACK is the reply of the
previous chained I-PDU sent by the target. The target did not received
it on the first attempt and it is being re-sent by the initiator. The
process continues as usual.
- No ATN PDU received before this ACK PDU. This is the reply of a
chained I-PDU. The target keeps on processing its chained I-PDU.
The code has been refactored to avoid too many indentation levels.
Also, ACK and NACK PDUs were not freed. This is now fixed.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When the initiator sends a DEP_REQ I-PDU, the target device may not
reply in a timely manner. In this case the initiator device must send an
attention PDU (ATN) and if the recipient replies with an ATN PDU in
return, then the last I-PDU must be sent again by the initiator.
This patch fixes how the target handles I-PDU received after an ATN PDU
has been received.
There are 2 possible cases:
- The target has received the initial DEP_REQ and sends back the DEP_RES
but the initiator did not receive it. In this case, after the
initiator has sent an ATN PDU and the target replied it (with an ATN
as well), the initiator sends the saved skb of the initial DEP_REQ
again and the target replies with the saved skb of the initial
DEP_RES.
- Or the target did not even received the initial DEP_REQ. In this case,
after the ATN PDUs exchange, the initiator sends the saved skb and the
target simply passes it up, just as usual.
This behavior is controlled using the atn_count and the PNI field of the
digital device structure.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When allocating chained I-PDUs, there is no need to call skb_reserve()
since it's already done by digital_alloc_skb() and contains enough room
for the driver head and tail data.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This patch fixes the way an I-PDU is saved in case it needs to be sent
again. It is now copied using pskb_copy() and not simply referenced
using skb_get() since it could be modified by the driver.
digital_in_send_saved_skb() and digital_tg_send_saved_skb() still get a
reference on the saved skb which is re-sent but release it if the send
operation fails. That way the caller doesn't have to take care about skb
ref in case of error.
RTOX supervisor PDU must not be saved as this can override a previously
saved I-PDU that should be re-sent later on.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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>
The Digital Protocol stack used to send a NACK frame whatever the error
type it receives in digital_in_recv_dep_res(). It actually should only
send a NACK frame on CRC or parity check errors or on any transmission
error if a NACK frame was previously sent. Existing drivers used to send
EIO error for this kind of issues so this patch limits sending of NACK
frames on EIO errors. All other errors will be reported to the upper
layers.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When configured as a target listening for a SENSF_REQ poll command, a
nfcid2 array was allocated for no reason leading to a memory leak. The
nfcid2 is sent by the target in the SENSF_RES reply.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The nfcsim driver now depends on the Digital layer. This patch adds the
missing dependency on NFC_DIGITAL for NFC_SIM config.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
If a command is still being processed by the device, the switch RF off
command will be rejected. With this patch, the port100 driver calls
port100_abort_cmd() before sending the switch RF off command.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This patch makes the abort_cmd function synchronous. This allows the
caller to immediately send a new command after abort_cmd() returns.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The USB out_urb used to send commands to the device can be submitted
through the standard command processing queue coming from the Digital
Protocol layer but it can also be submitted from port100_abort_cmd().
To not submit the URB while already active, a mutex is now used to
protect it and a cmd_cancel flag is used to not send command while
canceling the previous one.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This patch ensures that a command is not still in process before sending
a new one to the device. This can happen when neard is in constant
polling mode: the configure_hw command can be sent when neard restarts
polling after a LLCP SYMM timeout but before the device has returned in
timeout from the last DEP frame sent.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Once copied into the sk_buff data area using llcp_add_tlv(), the
allocated TLVs must be freed.
With this patch nfc_llcp_send_connect() and nfc_llcp_send_cc() don't
return immediately on success and now free the allocated TLVs.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In functions using llcp_add_tlv(), a skb pointer could be set to NULL
and then reuse afterward.
With this patch, the skb pointer returned by llcp_add_tlv() is ignored
since it can only be the passed skb pointer or NULL when the passed TLV
is NULL. There is also no need to check for the TLV pointer as this is
done by llcp_add_tlv().
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
With this complete rewrite, the loopback nfcsim driver now relies on the
Digital layer of the nfc stack. As with the previous version, 2 nfc
devices are declared when the driver is initialized. The driver supports
the NFC_DEP protocol in NFC-A and NFC-F technologies.
The 2 devices are using a pair of virtual links for sk_buff exchange.
The out-link of one device is the in-link of the other and conversely.
To receive data, a device calls nfcsim_link_recv_skb() on its in-link
and waits for incoming data on a wait queue. To send data, a device
calls nfcsim_link_send_skb() on its out-link which stores the passed skb
and signals its wait queue. If the peer device was in the
nfcsim_link_recv_skb() call, it will be signaled and will be able to
pass the received sk_buff up to the Digital layer.
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
LLCP skb tx and rx functions now use print_hex_dump_debug() making
these verbose traces controllable using dynamic debug.
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>
Thierry Escande