Bluetooth: Fix race between stop_discovery and le_scan_disable work

If a MGMT Stop Discovery command is sent while the le_scan_disable
work is running, two HCI_OP_LE_SET_SCAN_ENABLE are sent to the
controller. This situation can lead us to undesired behavior such as
MGMT Stop Discovery command fails and the discovery procedure keeps
running.

In order to fix this race condition, we should check if the le_scan_
disable work was properly canceled. If the work was canceled, then we
should send the HCI_OP_LE_SET_SCAN_ENABLE command to disable the
ongoing scanning. However, if the work could not be canceled (it means
it is now running), we should not send another HCI_OP_LE_SET_SCAN_ENABLE
command.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Remove stop discovery handling from hci_event.c

Since all mgmt stop discovery command complete events are now handled
in stop_discovery_complete callback in mgmt.c, we can remove this
handling from hci_event.c.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Refactor hci_cc_le_set_scan_enable

This patch does a trivial refactoring in hci_cc_le_set_scan_enable.
Since start and stop discovery command failures are now handled in
mgmt layer, the status check became empty. So, we can move it to
outside the switch statement.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Remove LE scan helpers

This patch removes the LE scan helpers hci_le_scan and hci_cancel_
le_scan and all code related to it. We now use the HCI request
framework in device discovery functionality and these helpers are
no longer needed.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Remove inquiry helpers

This patch removes hci_do_inquiry and hci_cancel_inquiry helpers. We
now use the HCI request framework in device discovery functionality
and these helpers are no longer needed.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Remove empty event handler

This patch removes the hci_cc_le_set_scan_param event handler. This
handler became empty because failures of this event are now handled
by start_discovery_complete function in mgmt.c.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Mgmt Device Found Event

We only want to send Mgmt Device Found Events if we are running the
Device Discovery procedure (started by the MGMT Start Discovery
Command). Inquiry or LE scanning triggered by HCI raw interface (e.g.
hcitool) or kernel internals should not send Mgmt Device Found Events.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>