Граф коммитов

33275 Коммитов

Автор SHA1 Сообщение Дата
Marcel Holtmann 89bc22d23f Bluetooth: Add quirk for invalid controller address setting
When a Bluetooth controller does not have a valid public Bluetooth
address, then allow the driver to indicate this. If the quirk is
set, the Bluetooth core will switch to unconfigured state first
and will allow userspace to configure the address before starting
the full initialization of the controller.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-04 18:09:32 +03:00
Johan Hedberg d1dbf12e3b Bluetooth: Use list_del when freeing the list entry
It's wasteful to use list_del_init (which re-initializes the list_head)
if we're just about to free the element and never use it again.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 15:54:29 +02:00
Johan Hedberg 99a6768e0e Bluetooth: Don't take actions on blocked devices when scanning
If a found device is marked as blocked while doing passive LE scanning,
neither report it nor try to connect to it.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 15:54:29 +02:00
Johan Hedberg a7545f2afc Bluetooth: Use hci_pend_le_action_lookup to look up report entries
Instead of looking through the entire list of entries we can more
efficiently use the new hci_pend_le_action_lookup() function to look up
entries specifically in the pend_le_reports list. Since the search is
now limited to the right list we can also remove an unnecessary check
for list_empty() before the lookup.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:10 +02:00
Johan Hedberg 501f882741 Bluetooth: Make hci_pend_le_conn_lookup more general purposed
In some circumstances we need to look up entries in pend_le_conns and in
other in pend_le_reports. This patch converts the existing lookup
function for pend_le_conns to something that can be used for both lists.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:10 +02:00
Johan Hedberg d9b3ad7df1 Bluetooth: Remove unused hci_pend_le_conn_add function
Since there are no more users of this function we can simply go ahead
and remove it.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:09 +02:00
Johan Hedberg 418025d1c3 Bluetooth: Remove unnecessary usage of hci_pend_le_conn_add
This is the last place using hci_pend_le_conn_add() and we can more
just as simply manipulate the list directly here.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:09 +02:00
Johan Hedberg d7347f3cc2 Bluetooth: Fix clearing and restarting all LE actions on power cycle
When powering off (hci_dev_do_close) we should clear both the
pend_le_reports and pend_le_conns types of entries. When powering on
respectively we should populate both lists. This patch converts the
hci_pend_le_conns_clear() function into hci_pend_le_actions_clear()
(which can now be static) and converts the restart_le_auto_conns()
function into restart_le_actions().

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:09 +02:00
Johan Hedberg ae44e5d19e Bluetooth: Remove unused hci_pend_le_conn_del() function
Now that there are no-longer any users of the hci_pend_le_conn_del()
function we can simply go ahead and remove it.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:09 +02:00
Johan Hedberg 95305baa77 Bluetooth: Simplify hci_conn_params->action list usage
Since params->action is used for both the pend_le_conns and
pend_le_reports lists we can simplify the adding and deleting of the
lists considerably. For example, when deleting entries in most
situations we no-longer need to check the auto_connect value but can
directly proceed with calling list_del_init on param->action (which is
safe even if the entry is not part of any list).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:09 +02:00
Johan Hedberg 42ce26de67 Bluetooth: Don't bother doing anything if auto_connect doesn't change
When hci_conn_params_set() is called if the new auto_connect value is
the same as the old one we don't need to take any action. Simply return
success from the function in this case.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:09 +02:00
Johan Hedberg a2f41a8f37 Bluetooth: Simplify use of hci_pend_le_conns_clear()
Now that pend_le_connections is a list of hci_conn_params entries we can
simply remove items from that list as we iterate through the global list
of le_conn_params. This also moves the responsibility of calling
hci_update_background_scan() to the functions that were previously
calling hci_pend_le_conns_clear(). The only user that's left for
hci_pend_le_conns_clear() is hci_dev_do_close() which anyway does not
need to call hci_update_background_scan().

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:09 +02:00
Johan Hedberg 66f8455aea Bluetooth: Convert pend_le_reports into a list
To simplify manipulation and lookup of hci_conn_params entries of the
type HCI_AUTO_CONN_REPORT it makes sense to store them in their own
list. The new action list_head in hci_conn_params is used for this
purpose.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:08 +02:00
Johan Hedberg 93450c7544 Bluetooth: Convert pend_le_conn list to a generic action list
In preparation to store also HCI_AUTO_CONN_REPORT entries in a list it
makes sense to convert the existing pend_le_conn list head of
hci_conn_params into a more generically named "action". This makes sense
because a parameter entry will never participate in more than one action
list.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:08 +02:00
Johan Hedberg 97bf2e9993 Bluetooth: Fix missing return statement in process_adv_report
If we're doing passive scanning we shouldn't proceed with any of the
code that deals with active scanning (pending reports, etc.). This patch
fixes a missing return statement for the passive scanning section in the
process_adv_report() function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-04 11:58:08 +02:00
Marcel Holtmann 9fc3bfb681 Bluetooth: Add support for controller configuration info command
The Read Controller Configuration Information command allows retrieving
details about possible configurations option. The supported options are
returned and also the missing options (if any).

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-04 08:50:19 +03:00
Johan Hedberg 738f61859d Bluetooth: Add identity address check in param lookup functions
Since we only store entries with identity addresses in the
le_conn_params and pend_le_conns lists we can avoid unnecessary lookups
by checking for an identity address before diving into the lists
themselves.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 18:45:09 +02:00
Johan Hedberg bb5ce4d018 Bluetooth: Remove unnecessary checks for auto-connected devices
If a device is in the pend_le_conns list it cannot at the same time also
have the need to be notified through mgmt_device_found. By making
check_pending_le_conn return whether it found an entry or not we can
avoid unnecessary checks in process_adv_report().

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 18:45:08 +02:00
Johan Hedberg 912b42ef05 Bluetooth: Use hci_conn_params in pend_le_conns
Since the connection parameters are always a basis for adding entries to
hdev->pend_le_conns (so far of type bdaddr_list) it's simpler and more
efficient to have the parameters themselves be the entries in the
pend_le_conns list. We do this by adding another list_head to the
hci_conn_params struct.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 18:45:08 +02:00
Johan Hedberg 435a13d839 Bluetooth: Remove redundant IRK lookup
When processing passive scanning results we need the resolved identity
address both in check_pending_le_conn() as well as later in
process_adv_report(). Since process_adv_report() calls
check_pending_le_conn() we can simply resolve the IRK earlier in the
function and thereby eliminate a second lookup.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 18:45:08 +02:00
Johan Hedberg 617ca1bf11 Bluetooth: Fix missing update of pend_le_reports
When calling Remove Device for an entry using HCI_AUTO_CONN_REPORT we
need to decrement the pend_le_reports value correspondingly. This patch
fixes one such missing action in the Remove Device command handler.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 18:45:08 +02:00
Johan Hedberg ba1d6936f6 Bluetooth: Fix buffer overflow with variable length commands
The handler for variable length commands were trying to calculate the
expected length of the command based on the given parameter count, and
then comparing that with the received data. However, the expected count
was stored in a u16 which can easily overflow. With a carefully crafted
command this can then be made to match the given data even though the
parameter count is actually way too big, resulting in a buffer overflow
when parsing the parameters.

This patch fixes the issue by calculating a per-command maximum
parameter count and returns INVALID_PARAMS if it is exceeded.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:59 +02:00
Johan Hedberg 079446c8a2 Bluetooth: Support scanning for devices using RPA
When we're scanning for specific devices that use an RPA we need to
convert the RPA to the identity address before looking up the entry in
the connection parameters. This patch adds the necessary code to do this
in the process_adv_report() function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:59 +02:00
Johan Hedberg 0d2bf13462 Bluetooth: Add support for background LE scanning
If we have one or more devices with HCI_AUTO_CONN_REPORT we should do
background scanning and emit mgmt_device_found events. This patch
modifies the hci_update_background_scan() function to extend the
conditions needed to trigger scanning, and adds the necessary code to
process_adv_report() to emit mgmt_device_found events.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:59 +02:00
Johan Hedberg 75ce208cc4 Bluetooth: Allow mgmt_device_found events for kernel-side scanning
When the kernel is doing LE scanning because of one or more devices
added with action 0x00 through the Add Device command we do want to let
mgmt_device_found() to proceed with sending an event. This kind of
devices are tracked with hdev->pend_le_reports, so check this value
before bailing out from the function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:59 +02:00
Johan Hedberg 851efca838 Bluetooth: Track number of added devices with HCI_AUTO_CONN_REPORT
To be able to make the right choice of whether to start passive scanning
or to send out a mgmt_device_found event we need to know if there are
any devices in the le_conn_params list with the auto_connect value set
to HCI_AUTO_CONN_REPORT. This patch adds a counter for this kind of
devices.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:58 +02:00
Marcel Holtmann 73d1df2a7a Bluetooth: Add support for Read Unconfigured Index List command
This command allows to get the list of currently known controller that
are in unconfigured state.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-03 17:42:58 +02:00
Marcel Holtmann edd3896bc4 Bluetooth: Add support for Unconfigured Index Removed events
When a controller in an unconfigured state gets removed, then send
Unconfigured Index Removed events.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-03 17:42:58 +02:00
Marcel Holtmann 0602a8adc3 Bluetooth: Add support for Unconfigured Index Added events
When a controller is in unconfigured state it is currently hidden
from the management interface. This change now announces the new
controller with an Unconfigured Index Added event and allows clients
to easily detect the controller.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-03 17:42:58 +02:00
Marcel Holtmann 4a964404c0 Bluetooth: Introduce unconfigured controller state
With the new unconfigured controller state it is possible to provide a
fully functional HCI transport, but disable the higher level operations
that would normally happen. This way userspace can try to configure the
controller before releases the unconfigured state.

The internal state is represented by HCI_UNCONFIGURED. This replaces the
HCI_QUIRK_RAW_DEVICE quirk as internal state representation. This is now
a real state and drivers can use the quirk to actually trigger this
state. In the future this will allow a more fine grained switching from
unconfigured state to configured state for controller inititialization.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-03 17:42:58 +02:00
Johan Hedberg c103aea6f7 Bluetooth: Don't send connection parameters without identity address
If we don't have an identity address for connection parameters it
doesn't really make sense to send them to user space. Instead just
ignore them for now. Later we can add support for sending them when we
eventually get the identity through pairing.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:58 +02:00
Johan Hedberg c46245b3ef Bluetooth: Make is_identity_address a global function
There are more places that can take advantage of is_identity_address()
besides hci_core.c. This patch moves the function to hci_core.h and
gives it the appropriate hci_ prefix.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:57 +02:00
Johan Hedberg f4869e2adb Bluetooth: Pass store hint to mgmt_new_conn_param
The calling functions of mgmt_new_conn_param have more information about
the parameters, such as whether the kernel is tracking them or not. It
makes therefore sense to have them pass an initial store_hint value to
the mgmt_new_conn_param function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:57 +02:00
Johan Hedberg 7d6ca6939c Bluetooth: Make hci_le_conn_update return the store hint
The caller of hci_le_conn_update is directly interested in knowing what
the best value is for the store_hint parameter of the corresponding
mgmt event. Since hci_le_conn_update knows whether there were stored
parameters that were updated or not we can have it return an initial
store_hint value to the caller.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:57 +02:00
Johan Hedberg 348d50b8e9 Bluetooth: Fix missing update of conn params
We should update any stored connection parameters when we receive the LE
Remote Connection Parameter Request HCI event. This patch adds the
necessary code to the function that handles the event.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:57 +02:00
Johan Hedberg a26f3dcff2 Bluetooth: Add Load Connection Parameters command
This patch implements the new Load Connection Parameters mgmt command
that's intended to load the desired connection parameters for LE
devices.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:57 +02:00
Johan Hedberg c71593dd34 Bluetooth: Remove only enabled entries with Remove Device command
The Remove Device mgmt command is supposed to undo what the Add Device
command does. An entry added by Add Device cannot have the
HCI_AUTO_CONN_DISABLED auto_connect value, so we should treat this as an
invalid entry to remove. This patch adds the necessary pieces to the
Remove Device command handler so that it only removes entries which were
added by Add Device.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:57 +02:00
Johan Hedberg a3451d279f Bluetooth: Add new auto_conn value matching mgmt action 0x00
The 0x00 action value of mgmt means "scan and report" but do not
connect. This is different from HCI_AUTO_CONN_DISABLED so we need a new
value for it.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:57 +02:00
Johan Hedberg 55af49a8fe Bluetooth: Add specific connection parameter clear functions
In some circumstances we'll need to either clear only the enabled
parameters or only the disabled ones. This patch adds convenience
functions for this purpose.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:56 +02:00
Johan Hedberg 373110c5d3 Bluetooth: Rename hci_conn_params_clear to hci_conn_params_clear_all
We'll soon have specific clear functions for clearing enabled or
disabled entries, so rename the function that removes everything to
clear_all().

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:56 +02:00
Marcel Holtmann 96c2103a57 Bluetooth: Default to internal use manufacturer identifier
When allocating a new controller structure, then default to the internal
use value 0xffff first. Default to 0x0000 is a bad idea since that is
the manufacturer identifier of Ericsson Technology Licensing.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-03 17:42:56 +02:00
Johan Hedberg 837d502efc Bluetooth: Drop LE connections for blocked devices
Unlike BR/EDR we cannot reject LE connections of blocked devices but
have to do it as soon as we get a LE Connection Complete event. The
patch adds a blacklist check to the hci_le_conn_complete_evt function
and drops all connections for blocked devices.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:55 +02:00
Johan Hedberg e493150e36 Bluetooth: Centralize looking up blocked devices to l2cap_recv_frame
The ATT channel isn't the only one that we should ensure doesn't receive
data from blocked devices. SMP is another, and in general we don't want
data packets going to any of the various handlers. Therefore, add a
single check to the l2cap_recv_frame function.

The patch fixes at the same time the use of a correct address type. The
blacklist stores the values with the user space facing triple type
wheras hci_conn->dst_type uses the HCI address type (0x00 or 0x01).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:55 +02:00
Marcel Holtmann 24c457e270 Bluetooth: Add support for hdev->set_bdaddr callback handling
Some embedded controllers allow the programming of a public address
and this adds vendor support for supporting OEM confguration of such
addresses.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-03 17:42:55 +02:00
Andre Guedes ffb5a827d5 Bluetooth: Introduce "New Connection Parameter" Event
This patch introduces a new Mgmt event called "New Connection Parameter".
This event indicates to userspace the connection parameters values the
remote device requested.

The user may store these values and load them into kernel. This way, next
time a connection is established to that device, the kernel will use those
parameters values instead of the default ones.

This event is sent when the remote device requests new connection
parameters through connection parameter update procedure. This event is
not sent for slave connections.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:55 +02:00
Andre Guedes 662bc2e63d Bluetooth: Enable new LE meta event
The Bluetooth 4.1 introduces a new LE meta event called "LE Remote
Connection Parameter Request" event. In order to the controller
sends this event to host, we should enable it during controller
initialization.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:55 +02:00
Andre Guedes 9193c6e884 Bluetooth: Move LE event mask setting into init3 phase
During init2 phase, the LE local features have not be read yet so
we aren't able to rely on hdev->le_features to determine if the
controller supports the Connection Parameters Request Procedure.

For that reason, this patch moves LE event mask setting from init2
into init3 initialization phase.

The hdev->le_features mask will be checked by the next patch in order
to know if "LE Remote Connection Parameter Request Event" should be
enabled.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:55 +02:00
Andre Guedes 8e75b46a4f Bluetooth: Connection Parameter Update Procedure
This patch adds support for LE Connection Parameters Request Link
Layer control procedure introduced in Core spec 4.1. This procedure
allows a Peripheral or Central to update the Link Layer connection
parameters of an established connection.

Regarding the acceptance of connection parameters, the LL procedure
follows the same approach of L2CAP procedure (see l2cap_conn_param_
update_req function). We accept any connection parameters values as
long as they are within the valid range.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:54 +02:00
Johan Hedberg 2a8357f239 Bluetooth: Fix redundant device (un)blocked events
For the Block/Unblock Device mgmt commands we should only emit the
Blocked/Unblocked events on any socket except for the one which received
the command. The code was previously incorrectly trying to look up a
non-existent pending command and thereby ending up not skipping the
command socket for the event.

We can simplify the code a lot by simply sending the event directly from
the command handler functions. We have the reference to the command
socket available there which makes it easy to pass to the mgmt_event
function for skipping.

The only notable side-effect of this is that the old blacklisting
ioctl's no-longer cause mgmt events to be emitted, however as user space
versions using these ioctl's are not mgmt-aware this is acceptable.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-03 17:42:54 +02:00
Marcel Holtmann c83ed19d23 Bluetooth: Ensure that background scanning gets enabled on power on
The background scanning normally gets enabled during power on by
adding devices to the pending connection list. However devices
might be already on that list and the list of devices is empty,
then it is better to trigger the background manually.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-07-03 17:42:54 +02:00