When receiving an interface activation notification, if
the RF interface is NCI_RF_INTERFACE_NFCEE_DIRECT, we
need to ignore the following parameters and change the NCI
state machine to NCI_LISTEN_ACTIVE. According to the NCI
specification, the parameters should be 0 and shall be
ignored.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The NFCC sends an NCI_OP_RF_NFCEE_ACTION_NTF notification
to the host (DH) to let it know that for example an RF
transaction with a payment reader is done.
For now the notification handler is empty.
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>
According to the NCI specification, one can use HCI over NCI
to talk with specific NFCEE. The HCI network is viewed as one
logical NFCEE.
This is needed to support secure element running HCI only
firmwares embedded on an NCI capable chipset, like e.g. the
st21nfcb.
There is some duplication between this piece of code and the
HCI core code, but the latter would need to be abstracted even
more to be able to use NCI as a logical transport for HCP packets.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In order to communicate with an NFCEE, we need to open a logical
connection to it, by sending the NCI_OP_CORE_CONN_CREATE_CMD
command to the NFCC. It's left up to the drivers to decide when
to close an already opened logical connection.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
NFCEEs can be enabled or disabled by sending the
NCI_OP_NFCEE_MODE_SET_CMD command to the NFCC. This patch
provides an API for drivers to enable and disable e.g. their
NCI discoveredd secure elements.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
NFCEEs (NFC Execution Environment) have to be explicitly
discovered by sending the NCI_OP_NFCEE_DISCOVER_CMD
command. The NFCC will respond to this command by telling
us how many NFCEEs are connected to it. Then the NFCC sends
a notification command for each and every NFCEE connected.
Here we implement support for sending
NCI_OP_NFCEE_DISCOVER_CMD command, receiving the response
and the potential notifications.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The current NCI core only support the RF static connection.
For other NFC features such as Secure Element communication, we
may need to create logical connections to the NFCEE (Execution
Environment.
In order to track each logical connection ID dynamically, we add a
linked list of connection info pointers to the nci_dev structure.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
With the newly introduced pipes table hci_dev fields,
the nfc_hci_pipe2gate routine is no longer needed.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When a command is received, it is sometime needed to let the CLF driver do
some additional operations. (ex: count remaining pipe notification...)
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
We update the tracked pipes status when receiving HCI commands.
Also we forward HCI errors and we reply to any HCI command, even though
we don't support it.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
As there can be several pipes connected to the same gate, we need
to know which pipe ID to use when sending an HCI response. A gate
ID is not enough.
Instead of changing the nfc_hci_send_response() API to something
not aligned with the rest of the HCI API, we call nfc_hci_hcp_message_tx
directly.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In order to keep host source information on specific hci event (such as
evt_connectivity or evt_transaction) and because 2 pipes can be connected
to the same gate, it is necessary to add a table referencing every pipe
with a {gate, host} tuple.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Several pipes may point to the same CLF gate, so getting the gate ID
as an input is not enough.
For example dual secure element may have 2 pipes (1 for uicc and
1 for eSE) pointing to the connectivity gate.
As resolving gate and host IDs can be done from a pipe, we now pass
the pipe ID to the event received handler.
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>
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.
This makes the very common pattern of
if (genlmsg_end(...) < 0) { ... }
be a whole bunch of dead code. Many places also simply do
return nlmsg_end(...);
and the caller is expected to deal with it.
This also commonly (at least for me) causes errors, because it is very
common to write
if (my_function(...))
/* error condition */
and if my_function() does "return nlmsg_end()" this is of course wrong.
Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.
Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did
- return nlmsg_end(...);
+ nlmsg_end(...);
+ return 0;
I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.
One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
John W. Linville says:
====================
pull request: wireless-next 2014-12-08
Please pull this last batch of pending wireless updates for the 3.19 tree...
For the wireless bits, Johannes says:
"This time I have Felix's no-status rate control work, which will allow
drivers to work better with rate control even if they don't have perfect
status reporting. In addition to this, a small hwsim fix from Patrik,
one of the regulatory patches from Arik, and a number of cleanups and
fixes I did myself.
Of note is a patch where I disable CFG80211_WEXT so that compatibility
is no longer selectable - this is intended as a wake-up call for anyone
who's still using it, and is still easily worked around (it's a one-line
patch) before we fully remove the code as well in the future."
For the Bluetooth bits, Johan says:
"Here's one more bluetooth-next pull request for 3.19:
- Minor cleanups for ieee802154 & mac802154
- Fix for the kernel warning with !TASK_RUNNING reported by Kirill A.
Shutemov
- Support for another ath3k device
- Fix for tracking link key based security level
- Device tree bindings for btmrvl + a state update fix
- Fix for wrong ACL flags on LE links"
And...
"In addition to the previous one this contains two more cleanups to
mac802154 as well as support for some new HCI features from the
Bluetooth 4.2 specification.
From the original request:
'Here's what should be the last bluetooth-next pull request for 3.19.
It's rather large but the majority of it is the Low Energy Secure
Connections feature that's part of the Bluetooth 4.2 specification. The
specification went public only this week so we couldn't publish the
corresponding code before that. The code itself can nevertheless be
considered fairly mature as it's been in development for over 6 months
and gone through several interoperability test events.
Besides LE SC the pull request contains an important fix for command
complete events for mgmt sockets which also fixes some leaks of hci_conn
objects when powering off or unplugging Bluetooth adapters.
A smaller feature that's part of the pull request is service discovery
support. This is like normal device discovery except that devices not
matching specific UUIDs or strong enough RSSI are filtered out.
Other changes that the pull request contains are firmware dump support
to the btmrvl driver, firmware download support for Broadcom BCM20702A0
variants, as well as some coding style cleanups in 6lowpan &
ieee802154/mac802154 code.'"
For the NFC bits, Samuel says:
"With this one we get:
- NFC digital improvements for DEP support: Chaining, NACK and ATN
support added.
- NCI improvements: Support for p2p target, SE IO operand addition,
SE operands extensions to support proprietary implementations, and
a few fixes.
- NFC HCI improvements: OPEN_PIPE and NOTIFY_ALL_CLEARED support,
and SE IO operand addition.
- A bunch of minor improvements and fixes for STMicro st21nfcb and
st21nfca"
For the iwlwifi bits, Emmanuel says:
"Major works are CSA and TDLS. On top of that I have a new
firmware API for scan and a few rate control improvements.
Johannes find a few tricks to improve our CPU utilization
and adds support for a new spin of 7265 called 7265D.
Along with this a few random things that don't stand out."
And...
"I deprecate here -8.ucode since -9 has been published long ago.
Along with that I have a new activity, we have now better
a infrastructure for firmware debugging. This will allow to
have configurable probes insides the firmware.
Luca continues his work on NetDetect, this feature is now
complete. All the rest is minor fixes here and there."
For the Atheros bits, Kalle says:
"Only ath10k changes this time and no major changes. Most visible are:
o new debugfs interface for runtime firmware debugging (Yanbo)
o fix shared WEP (Sujith)
o don't rebuild whenever kernel version changes (Johannes)
o lots of refactoring to make it easier to add new hw support (Michal)
There's also smaller fixes and improvements with no point of listing
here."
In addition, there are a few last minute updates to ath5k,
ath9k, brcmfmac, brcmsmac, mwifiex, rt2x00, rtlwifi, and wil6210.
Also included is a pull of the wireless tree to pick-up the fixes
originally included in "pull request: wireless 2014-12-03"...
Please let me know if there are problems!
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The maximum size of ATR_REQ and ATR_RES is 64 bytes.
The maximum number of General Bytes is calculated by
the maximum number of data bytes in the ATR_REQ/ATR_RES,
substracted by the number of mandatory data bytes.
ATR_REQ: 16 mandatory data bytes, giving a maximum of
48 General Bytes.
ATR_RES: 17 mandatory data bytes, giving a maximum of
47 General Bytes.
Regression introduced in commit a99903ec.
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Fixing: net/nfc/nci/ntf.c:106:31: warning: cast to restricted __le16
message when building with make C=1 CF=-D__CHECK_ENDIAN__
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Fix warnings:
net/nfc/llcp_commands.c:421:14: warning: incorrect type in assignment (different base types)
net/nfc/llcp_commands.c:421:14: expected unsigned short [unsigned] [usertype] miux
net/nfc/llcp_commands.c:421:14: got restricted __be16
net/nfc/llcp_commands.c:477:14: warning: incorrect type in assignment (different base types)
net/nfc/llcp_commands.c:477:14: expected unsigned short [unsigned] [usertype] miux
net/nfc/llcp_commands.c:477:14: got restricted __be16
Procedure to reproduce:
make ARCH=x86_64 allmodconfig
make C=1 CF=-D__CHECK_ENDIAN__
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Some pipe are only created by other host (different than the
Terminal Host).
The pipe values will for example be notified by
NFC_HCI_ADM_NOTIFY_PIPE_CREATED.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
se_io allows to send apdu over the CLF to the embedded
Secure Element.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Some tag might get deactivated after some read or write tentative.
This may happen for example with Mifare Ultralight C tag when trying
to read the last 4 blocks (starting block 0x2c) configured as write
only.
NFC_CMD_ACTIVATE_TARGET will try to reselect the tag in order to
detect if it got remove from the field or if it is still present.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
nci_rf_deactivate_req only support NCI_DEACTIVATE_TYPE_IDLE_MODE.
In some situation, it might be necessary to be able to support other
NCI_DEACTIVATE_TYPE such as NCI_DEACTIVATE_TYPE_SLEEP_MODE in order for
example to reactivate the selected target.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
A notification for rf deaction can be IDLE_MODE, SLEEP_MODE,
SLEEP_AF_MODE and DISCOVERY. According to each type and the NCI
state machine is different (see figure 10 RF Communication State
Machine in NCI specification)
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The nci status byte was ignored. In case of tag reading for example,
if the tag is removed from the antenna there is no way for the upper
layers (aka: stack) to get inform about such event.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When switching from UICC to another, the CLF may signals to the Terminal
Host that some existing pipe are cleared for future update.
This notification needs to be "acked" by the Terminal Host with a ANY_OK
message.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
If our terminal connect with other host like UICC, it may create
a pipe with us, the host controller will notify us new pipe
created, after that UICC will open that pipe, if we don't handle
that request, UICC may failed to continue initialize which may
lead to card emulation feature failed to work
Signed-off-by: Arron Wang <arron.wang@intel.com>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
se_io allows to send apdu over the CLF to the embedded Secure Element.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Some NFC controller using NCI protocols may need a proprietary commands
flow to disable a secure element
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Some NFC controller using NCI protocols may need a proprietary commands
flow to enable a secure element
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Some NFC controller using NCI protocols may need a proprietary commands
flow to discover all available secure element
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Fix sparse warning introduced by commit: 9e87f9a9c4
It was generating the following warning:
net/nfc/nci/ntf.c:170:7: sparse: symbol 'nci_get_prop_rf_protocol' was not declared. Should it be static?
Procedure to reproduce it:
# apt-get install sparse
git checkout 9e87f9a9c4
make ARCH=x86_64 allmodconfig
make C=1 CF=-D__CHECK_ENDIAN__
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
se_io allows to send apdu over the CLF to the embedded Secure Element.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Before signaling the deactivation, send a deactivation request if in
RFST_DISCOVERY state because neard assumes polling is stopped and will
try to restart it.
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When the deactivation type reported by RF_DEACTIVATE_NTF is Discovery, go in
RFST_DISCOVERY state. The NFCC stays in Poll mode and/or Listen mode.
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
As specified in NCI 1.0 and NCI 1.1, when using the NFC-DEP RF Interface, the
DH and the NFCC shall only use the Static RF Connection for data communication
with a Remote NFC Endpoint.
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The Target responds to the ATR_REQ with the ATR_RES. Configure the General
Bytes in ATR_RES with the first three octets equal to the NFC Forum LLCP
magic number, followed by some LLC Parameters TLVs described in section
4.5 of [LLCP].
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Changes:
* Extract the Listen mode activation parameters from RF_INTF_ACTIVATED_NTF.
* Store the General Bytes of ATR_REQ.
* Signal that Target mode is activated in case of an activation in NFC-DEP.
* Update the NCI state accordingly.
* Use the various constants defined in nfc.h.
* Fix the ATR_REQ and ATR_RES maximum size. As per NCI 1.0 and NCI 1.1, the
Activation Parameters for both Poll and Listen mode contain all the bytes of
ATR_REQ/ATR_RES starting and including Byte 3 as defined in [DIGITAL].
In [DIGITAL], the maximum size of ATR_REQ/ATR_RES is 64 bytes and they are
numbered starting from Byte 1.
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Send LA_SEL_INFO and LF_PROTOCOL_TYPE with NFC-DEP protocol enabled.
Configure 212 Kbit/s and 412 Kbit/s bit rates for Listen F.
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The Target mode protocols are given to the nci_start_poll() function
but were previously ignored.
To enable P2P Target, when NFC-DEP is requested as a Target mode protocol, add
NFC-A and NFC-F Passive Listen modes in RF_DISCOVER_CMD command.
Signed-off-by: Julien Lefrique <lefrique@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
list_for_each_entry_safe() is necessary if list objects are deleted from
the list while traversing it. Not the case here, so we can use the base
list_for_each_entry variant.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
When an NFC-DEP target receives an ATN PDU, its
supposed to respond with a similar ATN PDU.
When the Target receives an I PDU with the PNI
one less than the current PNI and the last PDU
sent was an ATN PDU, the Target is to resend the
last non-ATN PDU that it has sent. This is
described in section 14.12.3.4 of the NFC Digital
Protocol Spec.
The digital layer's NFC-DEP code doesn't implement
this so add that support.
Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com>
Tested-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>
When an NFC-DEP Initiator times out when waiting for
a DEP_RES from the Target, its supposed to send an
ATN to the Target. The Target should respond to the
ATN with a similar ATN PDU and the Initiator can then
resend the last non-ATN PDU that it sent. No more
than 'N(retry,atn)' are to be send where
2 <= 'N(retry,atn)' <= 5. If the Initiator had just
sent a NACK PDU when the timeout occurred, it is to
continue sending NACKs until 'N(retry,nack)' NACKs
have been send. This is described in section
14.12.5.6 of the NFC-DEP Digital Protocol Spec.
The digital layer's NFC-DEP code doesn't implement
this so add that support.
The value chosen for 'N(retry,atn)' is 2.
Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com>
Tested-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>
When an NFC-DEP Target receives a NACK PDU with
a PNI equal to 1 less than the current PNI, it
is supposed to re-send the last PDU. This is
implied in section 14.12.5.4 of the NFC Digital
Protocol Spec.
The digital layer's NFC-DEP code doesn't implement
Target-side NACK handing so add it. The last PDU
that was sent is saved in the 'nfc_digital_dev'
structure's 'saved_skb' member. The skb will have
an additional reference taken to ensure that the skb
isn't freed when the driver performs a kfree_skb()
on the skb. The length of the skb/PDU is also saved
so the length can be restored when re-sending the PDU
in the skb (the driver will perform an skb_pull() so
an skb_push() needs to be done to restore the skb's
data pointer/length).
Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com>
Tested-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>
When an NFC-DEP Initiator receives a frame with
an incorrect CRC or with a parity error, and the
frame is at least 4 bytes long, its supposed to
send a NACK to the Target. The Initiator can
send up to 'N(retry,nack)' consecutive NACKs
where 2 <= 'N(retry,nack)' <= 5. When the limit
is exceeded, a PROTOCOL EXCEPTION is raised.
Any other type of transmission error is to be
ignored and the Initiator should continue
waiting for a new frame. This is described
in section 14.12.5.4 of the NFC Digital Protocol
Spec.
The digital layer's NFC-DEP code doesn't implement
any of this so add it. This support diverges from
the spec in two significant ways:
a) NACKs will be sent for ANY error reported by the
driver except a timeout. This is done because
there is currently no way for the digital layer
to distinguish a CRC or parity error from any
other type of error reported by the driver.
b) All other errors will cause a PROTOCOL EXCEPTION
even frames with CRC errors that are less than 4
bytes.
The value chosen for 'N(retry,nack)' is 2.
Targets do not send NACK PDUs.
Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com>
Tested-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>
When the peer in an NFC-DEP exchange has a
packet to send that is larger than the local
maximum payload, it sets the 'MI' bit in the
'I' PDU. This indicates that NFC-DEP chaining
is to occur.
When such a PDU is received, the local side
responds with an 'ACK' PDU and this continues
until the peer sends an 'I' PDU with the 'MI'
bit cleared. This indicates that the chaining
sequence is complete and the entire packet has
been transferred.
Receiving chained PDUs is currently not supported
by the digital layer so add that support. When a
chaining sequence is initiated by the peer, the
digital layer will allocate an skb large enough
to hold 8 maximum sized frame payloads. The maximum
payload can range from 64 to 254 bytes so 8 * 254 =
2032 seems like a reasonable compromise between
potentially wasting memory and constantly reallocating
new, larger skbs.
Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com>
Tested-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>
