Seems due to incorrect rebase in commit 07270e52ba
("Bluetooth: controller: Coding style and refactoring"),
commit 95d55a2bfc ("Bluetooth: controller: Do not skip
one-shot tickers with slot"), and
commit 4ba2bb0d1c ("Bluetooth: controller: Be fair when
pre-empting a ticker"), a pointless expression was
introduced, fixed it.
Coverity-CID: 171563
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fixes an assert during connection establishment when the
initiator overflows the initiator window in time while
sending the CONNECT_IND PDU. The actual window is one low
frequency tick less, hence corrected the check that permits
the transmission of CONNECT_IND PDU inside the initiator
window.
Symptom was, stopping of the scanner's ticker succeeds on
connection establishment, but next interval prepare was
already run when continuous scanning was used, breaking the
design, hence there was an assert.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Implement the Zephyr Read Key Hierarchy Roots command, returning the IR
and ER present in nRF5x ICs when compiling for those.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Implement the first Vendor-Specific Command of the Zephyr specification
other than the 3 mandatory ones already present in the codebase, along
with a Kconfig option to enable and disable the presence of the VS
commands.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
This is necessary in order for k_queue_get to work properly since that
is used with buffer pools which might be used by multiple threads asking
for buffers.
Jira: ZEP-2553
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Refactor the Connection Parameter Request Procedure to be
separate from and not overlap the variables of the
Connection Update Procedure.
Also, added missing implementations to pass all Connection
Parameter Request Procedure related Conformance Tests.
Jira: ZEP-1918
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Implement the LE Read Channel Map HCI command, along with making the
reading of the multi-byte channel map value from the connection pointer
thread-safe in case the ISR triggers while we are reading the value.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Although the current BLE controller only supports a single TX power (0
dBm), the qualification tests require the 2 Read TX Power to be
present and supported in the controller, so implement them while
returning always 0 dBm.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
When the CONFIG_BT_CTLR_CONN_RSSI option is set, the connection RSSI is
available in the controller, and can be reported to the Host via the
Read RSSI command. Implement the command, which is required for
qualification.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
There are 2 possible interpretations regarding the address to return in
response to the Read Peer RPA HCI Command:
1) The RPA that the local controller generates to be used in certain
packets it sends
2) The RPA generated and used by the peer device in its packets
We used to return 1) but our interpretation turned out to be incorrect
when reading the HCI test specification, so this commit switches to
returning 2).
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
In the ll_rl_pdu_adv_update() function, the check to verify if we are
dealing with an item from the resolving list or else with a simple
standard non-privacy enabled device was left over from the previous
iteration, which used negative values. Replace that check with the
proper current one, using the size of the rl array as an indicator of
whether the index is valid.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Due to varying remainder value, first interval will need to
consider the remainder value used in microsecond timing from
the start of the initiator window.
Also the tx chain delay and ready delay must be substract
after the window offset is calculated.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
The Read Remote Version Information command is supported on the BLE
controller, enable the bit in Read Local Supported Commands to reflect
this.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Fix controller assert due to a bug introduced in commit
07270e52ba ("Bluetooth: controller: Coding style and
refactoring").
This reverts implementation to original way it was and the
calculation of the ticker expiry will now not overflow the
range of the RTC peripheral, which is a 24 bit counter.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
The RSSI value is an 8-bit signed integer. Since the Link Layer works
only with positive unsigned integers, translate into a negative number
at the HCI layer.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Since Extended Scanner Filter Policies is an independent feature from
Controller-based Privacy, split it out so it can be built independently
and included without it.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Whenever privacy is enabled, we support the Extended Scan Filter
Policies functionality, and therefore we must show it in the bitfield of
LE supported features for the controller.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Rename the BT_CONTROLLER prefix used in all of the Kconfig variables
related to the Bluetooth controller to BT_CTLR.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Implement the 4.2 event LE Directed Advertising Report, used for
scanners in a privacy-enabled controller to report directed advertising
events whose TargetA cannot be resolved by the local controller.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Add implementation to support PHY update procedure with
packet transmit time restrictions.
This fixes:
TP/CON/SLA/BV-49-C [Initiating PHY Update Procedure Packet
Time Restrictions]
TP/CON/SLA/BV-50-C [Responding to PHY Update Procedure
Packet Time Restrictions]
TP/CON/SLA/BV-52-C [Initiating PHY Update Procedure Packet
Time Restrictions, No Change]
TP/CON/SLA/BV-53-C [Responding to PHY Update Procedure
Packet Time Restrictions, No Change]
TP/CON/MAS/BV-49-C [Initiating PHY Update Procedure Packet
Time Restrictions]
TP/CON/MAS/BV-50-C [Responding to PHY Update Procedure
Packet Time Restrictions]
conformance tests in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
The API name space for Bluetooth is bt_* and BT_* so it makes sense to
align the Kconfig name space with this. The additional benefit is that
this also makes the names shorter. It is also in line with what Linux
uses for Bluetooth Kconfig entries.
Some Bluetooth-related Networking Kconfig defines are renamed as well
in order to be consistent, such as NET_L2_BLUETOOTH.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Fix incorrect return data type, which causes controller to
hang generating random numbers.
Fixes bug introduced in commit d90095b556 ("Bluetooth:
controller: Use random numbers in adv and enc setup")
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
The specification requires the scanner to verify that the AdvA present
in a scan response matches the AdvA that was sent in the original scan
request.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Added implementation to get random numbers in ISR. And fixed
implementation to use random numbers in advertisement random
delay and encryption setup procedure.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
The existing check for the TargetA address in directed advertising
events was incorrect. In fact the specification states:
"An initiator that has been instructed by the Host to use
Resolvable Private Addresses shall not respond to directed connectable
advertising events that contain Public or Static addresses for the
target’s address (TargetA field)."
Hence, reject TargetA values that have not been successfully resolved
when the controller is generating its own RPAs.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
To be able to get a hit on the AAR whenever a Scan Response is received,
enable it in the state transition.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Add missing checks for the logic that discriminates between whitelisting
and non-whitelisting filtering, so that we do not fall into an
unsuspected false positive.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Rework the ctrl_lrpa_get() function so that it doesn't require an
assignment to be present inside the if statement, yielding smaller and
safer code.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Advertising reports generated by a scanner require the controller to
look up the resolving list to supply the host with an ID address instead
of the RPA that has been sent over the air.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Use the actual scanner address to copy the generated RPA into, instead
of mistakenly copying it into the advertiser's address.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Whenever trying to generate a local RPA to send a scan request or a conn
ind, verify that it can be generated (i.e. no NULL IRK provided by the
Host) and fall back to using the public/random address if required.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Since the hardware expects big-endian IRKs but the common generation
function expects it in little-endian, copy and reverse the peer IRK
before generating RPAs.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Implement the LE Enhanced Connection Complete HCI event, but include it
only when controller-based privacy is enabled, since it is only relevant
with it.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Since a connection attempt can fail and will still generate an LE
Connection Complete event, check the status from the LL control module
before incrementing the HCI connection count used for flow control.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The nRF5 AAR requires the packet pointer to be placed exactly 3 bytes
before the beginning of the address. Since we don't use the S1 extra
length byte, substract one from the address of the radio packet pointer.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The currently supported hardware in the LL requires big-endian IRK
values to properly function. Reverse the order of the IRK bytes coming
from HCI to address this issue.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The nRF5's AAR was being improperly configured, leading to a NULL
scratch pointer which made it not function at all.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
In order to make sure that the ISR never gets an incomplete or partial
local RPA, use pointers to share the local RPA between thread mode and
ISRs. Pointer updates are guaranteed to be atomic at least on ARM
Cortex-M.
Additionally add support for using local RPAs when initiating a
connection or sending a scan request.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Since the hardware is only able to resolve the first address in the
packet, use the existing functionality to resolve a potential TargetA
RPA in software to verify if it matches the local device.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
This commit introduces controller-based privacy for both the scanner and
the initiator roles. All the features in the specification are
implemented except:
* RPA resolution for directed advertising (TargetA address)
* RPA generation for scan requests and conn ind packets
Follow-up patches will cover the 2 items of functionality still missing
from the basic implementation. Hosts not using controller-based privacy
should not be affected by this change.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Control and Data packet Tx queue management updated to be
optimal and defer control packet responses when Tx is paused
during encryption setup.
This fixes:
TP/SEC/MAS/BV-12 [Master Start Encryption: Overlapping
Procedure]
TP/SEC/MAS/BV-13 [Master Start Encryption: Overlapping
Procedure with LL_SLAVE_FEATURES_REQ]
conformance tests in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix handling of different procedure collision when receiving
a PHY update request and handling of reject extended
indication.
This fixes:
TP/CON/MAS/BV-47-C [Handling Protocol Collision – Different
Procedure – Channel Map],
TP/CON/SLA/BV-46-C [Handling Protocol Collision – Different
Procedure – Channel Map] and
TP/CON/SLA/BV-48-C [Handling Protocol Collision – Different
Procedure – Connection Update]
conformance test in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix missing PHY update event generation on same procedure
collision,
This fixes TP/CON/SLA/BV-44-C [Handling Protocol Collision –
Same Procedure] conformance test in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix PHY update procedure intiation to use correct No Change
value in MtoS and StoM when there is no change to respective
PHYs. Also, added missing HCI event generation under this
case.
This fixes TP/CON/MAS/BV-41-C [Initiating PHY Update
Procedure] conformance test in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
As ticker can only drift in 32kHz units, the slave Rx
window should consider a +/- one 32kHz unit in addition to
+/- 16us jitter of the master. Hence, for the current
implementation the slave Rx window jitter is +/- 48us.
Future improvement can be done by using remainder of 32kHz
unit drift to reduce this jitter to +/- 16us.
With this fix 20ppm clock accuracy passes conformance TIM
tests (else 251-500ppm had to be used).
Problem was not seen in real life as master do not have a
+/- 16us jitter.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix terminate procedure timeout when supervision timeout
equals connection interval. In this case, avoid timing out
in the first event of procedure initiation.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix slave implementation to initiate reject_ext_ind if peer
supports reject_ext_ind.
This fixes:
TP/SEC/SLA/BV-11-C [Slave Sending Reject_Ind_Ext]
conformance test in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix handling invalid control PDUs by generating
LL_UNKNOWN_RSP PDU.
This fixes:
TP/PAC/SLA/BV-01-C [Unknown Packet from Master]
TP/PAC/MAS/BV-01-C [Unknown Packet from Slave]
conformance tests in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix access address generation to correctly have two
transitions in the six MS bits and add other missing checks.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Minor cleanup of Encryption Restart Procedure; No need to
pause rx for slave role on reception of PAUSE_ENC_RSP PDU as
its already paused.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix assert in the controller on master connection creation
due to the CONNECT_IND PDU being transmitted beyond the
calculated scan window.
This is related to commit 80a796b493 ("Bluetooth:
controller: Fix scanner to use correct slot ticks")
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix an assert in next role event preparation when a
connection terminated during the connection event being
aborted/pre-empted out by the next role event.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
When populating the hardware filter, add only slots that are marked as
taken to avoid the hardware being confused by all-0 addresses. This
solves an EBQ issue with whitelist filtering.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
To avoid warnings (seen on some machines) that a function reaches its
end without returning a value, conditionally compile the function in a
way that this cannot happen.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Fix master terminate procedure so that if slave responded to
the ack from master for the LL_TERMINATE_IND then the master
correctly disconnected.
This fixes TP/CON/MAS/BV-09-C [Master Accepting Termination]
in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Tested-by: Ulrich Myhre <ulmy@nordicsemi.no>
Fix implementation to maintain a connection in the slave
role not taking slave latency into use before receiving an
acknowledgement from the master.
This fixes TP/CON/ADV/BV-03-C [Master Missing Slave Packets]
in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Tested-by: Ulrich Myhre <ulmy@nordicsemi.no>
When the controller is configured to have its worker and job
be run at different interrupt priority, check for mayfly
priority being equal was incorrect.
Fixed by conditionally compiling the correct check of mayfly
priority level.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fixed a defect wherein anchor for first scanner event was in
the past (when looking for a free timeslice to avoid
overlapping with master role events) when actually there
were no master roles active. This defect caused the scanner
role to assert, when started with other roles active (eg.
advertiser), when trying to catch-up to current tick.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
This reverts commit 3c23c6f53d ("Bluetooth: controller:
Fix assert due to stale tick count") as this leads to
connection events to be skipped, failing conformance tests.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
This reverts commit b5235207d3 ("Bluetooth: controller:
Fix for scanner Rx window hang") as this leads to
connection events to be skipped, failing conformance tests.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Fix calculation of T_Terminate and other procedure timers by
using ceil on calculated connection interval units.
This fixes TP/CON/MAS/BI-02-C [Master T_Terminate Timer] and
TP/CON/SLA/BI-02-C [Slave T_Terminate Timer] in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Signed-off-by: Ulrich Solli Myhre <ulmy@nordicsemi.no>
Fix implementation so that both slave and master behave same
during connection setup and generate disconnection complete
with reason 0x3e (connection failed to be established).
This fixes TP/CON/ADV/BV-02-C [Accepting Connections
Timeout] in LL.TS.5.0.0.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Signed-off-by: Ulrich Solli Myhre <ulmy@nordicsemi.no>
Whenever not using the whitelist the resolving list is traversed to
verify that the device is allowed depending on its current privacy mode.
In the case where the device is not found by address in the resolving
list, allow the request to go through, since we are then dealing with an
unknown devices and the resolving list restrictions do not apply.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The specification states that the AdvA in a Scan Request packet should
be identical to the one sent in the original advertising packet, so
check this when processing a Scan Request.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
When the initiator is using an RPA and we match it using the filtering,
we should return early and allow the device packet through instead of
going through the whole resolving list.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The specification states that filter policies shall be ignored for
directed advertising, so reflect this behaviour in the code.
Additionally when the local device is using RPAs but the peer uses an
identity address, the resolving list index needs to be updated when
traversing the RL to reflect that there has indeed been a device match
even though the IRK match did not happen.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The AdvA in the CONN_IND packet must match the AdvA in the advertising
packet that triggered it regardless of the advertising type.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Added BUILD_ASSERT check for Tx and Rx thread priorities.
The Tx thread priority shall be higher than Rx thread
priority in order to correctly detect transaction violations
in ATT and SMP protocols. The Number of Completed Packets
for a connection shall be processed before any new data is
received and processed for that connection.
The Controller's priority receive thread priority shall be
higher than the Host's Tx and the Controller's Rx thread
priority.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
For consistency with the Resolving List, rename the whitelist filter to
match its type and the privacy-enabled version to align it with the
short name used in the RL.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
To correctly handle the allocation and deallocation of resolving list
items, the ll_rl_find and wl_pees_find functions have been modified to
return an invalid index instead of a negative value in case of error.
This is to avoid the ambiguity when mixing indices and negative numbers,
which does not play well with the first index 0.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The following error and warning is received when connecting
to certain central devices:
[bt] [ERR] hci_num_completed_packets: packets count mismatch
[bt] [WRN] bt_att_recv: Ignoring unexpected request
This could happen if Tx-ed packet is not added to pending
list before a num of completed packets event and/or new Rx
packet is received.
This is fixed by reducing the Rx thread priorities in the
Host and the Controller.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Due to the missing remainder support in the ticker_start
function for first interval, fix implementation so as to
round the first interval/offset during master connection
setup and connection update to within +/-16us.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
The HCI Read Remote Version Information Complete event structure was
incorrect, leading to qualification test failures. This patch fixes the
structure and also the storing of the data in an endianness-agnostic
manner.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
To avoid manipulation of the irkmatch_ok and irkmatch_id, rely instead
on Resolving List indices for all checks in the advertising ISR.
Although we do incur in a small overhead to look it up initially, the
overall gains are worth the change.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
The Controller reserved more than required time for
advertisement event length. Due to this, directed
advertisements did not meet the required <= 3.75ms
interval. It is now fixed by having event lengths based
on the advertisement PDU types.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Correct the default value (0x0) for the Event Mask Page 2 and add the
command to set it to the list of supported commands.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Correctly filter out the Authenticated Payload Timeout Expired event
based on the bit present on page 2 of the Event Mask.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
In order to be able to filter events present in Page 2 of the Event
Mask, this command allows the Host to set the Page 2 of the bitmask
through the corresponding command.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Reset and initialize filters correctly based on whether privacy is
enabled in the controller. Particularly relevant in the case of the
whitelist, which is handled in a completely different way if privacy is
enabled. Additionally reset the peer IRK list in the resolving list
whenever the list itself is cleared.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
When flashing in synchronous mode with BLE roles active,
ticker function calls will be deferred to avoid radio ISR
latencies. Increase the total operations supported by 1, to
accommodate flash driver's use of ticker operations.
It has been observed, without this increase, either the
flash driver returned -ECANCEL or the BLE Controller
asserted on data transmit as a slave (trying to force data
transmit on earliest connection event interval).
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
Implement privacy-enabled filtering in the advertiser role. This
includes all required checks when running address generation and
resolution so that the advertiser complies with the relevant
specification sections.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
Fix missing re-initialization of ret_cb to
TICKER_STATUS_BUSY before every new call to ticker interface
functions' with operation's callback.
One issue was undirected advertisement disable to return
failure status in the scan_adv sample.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
With the fix in commit 3c23c6f53d ("Bluetooth: controller:
Fix assert due to stale tick count") it is required that a
skipping event shall abort the previous role in order to
enable the ticker_job to resume and reschedule next ticker
expiry.
In the scan_adv sample, with continuous scanning, an
advertiser would pre-empt it, but if the advertiser skipped
its event without aborting the scanner, the scanner is hung
with its rx window without a timeout, and HCI command to
stop the advertiser will wait forever to complete.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>
The scanner was reserving a little less slot ticks which
caused other roles to overlap before scan window could
close.
Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>