Bluetooth: Rename hci_request to hci_req_sync

We'll be introducing an async version of hci_request. To make things
clear it makes sense to rename the existing API to have a _sync suffix.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Fix __hci_request() handling of empty requests

If a request callback doesn't send any commands __hci_req_sync() should
fail imediately instead of waiting for the inevitable timeout to occur.
This is particularly important once we start creating requests with
conditional command sending which can potentially result in no commands
being sent at all.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Split HCI init sequence into three stages

Having conditional command sending during a request has always been
problematic and caused hacks like the hdev->init_last_cmd variable. This
patch removes these conditionals and instead splits the init sequence
into three stages, each with its own __hci_req_sync() call.

This also paves the way to the upcoming asynchronous request support
swhich will also benefit by having a simpler implementation if it
doesn't need to cater for requests that change on the fly.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Add initial skeleton for asynchronous HCI requests

This patch adds the initial definitions and functions for asynchronous
HCI requests. Asynchronous requests are essentially a group of HCI
commands together with an optional completion callback. The request is
tracked through the already existing command queue by having the
necessary context information as part of the control buffer of each skb.

The only information needed in the skb control buffer is a flag for
indicating that the skb is the start of a request as well as the
optional complete callback that should be used when the request is
complete (this will be found in the last skb of the request).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Refactor HCI command skb creation

This patch moves out the skb creation from hci_send_cmd() into its own
prepare_cmd() function. This is essential so the same prepare_cmd()
function can be easily reused for skb creation for asynchronous HCI
requests.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Introduce new hci_req_add function

This function is analogous to hci_send_cmd() but instead of directly
queuing the command to hdev->cmd_q it adds it to the local queue of the
asynchronous HCI request being build (inside struct hci_request).

This is the main function used for building asynchronous requests and
there should be one or more calls to it between calls to hci_req_init
and hci_req_run.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Fix stand-alone HCI command handling

To have a consistent content for hdev->cmd_q all entries need to follow
the semantics of asynchronous HCI requests. This means that even single
commands need to be dressed as requests by having a request start
indicator. This patch adds these indicators to the two places needing
it (hci_send_cmd and hci_sock_sendmsg).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Add request cmd_complete and cmd_status functions

This patch introduces functions to process the HCI request state when
receiving HCI Command Status or Command Complete events. Some HCI
commands, like Inquiry do not result in a Command complete event so
special handling is needed for them. Inquiry is a particularly important
one since it is the only forseeable "non-cmd_complete" command that will
make good use of the request functionality, and its completion is either
indicated by an Inquiry Complete event of a successful Command Complete
for HCI_Inquiry_Cancel.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Use async requests internally in hci_req_sync

This patch converts the hci_req_sync() procedure to internaly use the
asynchronous HCI requests.

The hci_req_sync mechanism relies on hci_req_complete() calls from
hci_event.c into hci_core.c whenever a HCI command completes. This is
very similar to what asynchronous requests do and makes the conversion
fairly straight forward by converting hci_req_complete into a request
complete callback. By this change hci_req_complete (renamed to
hci_req_sync_complete) becomes private to hci_core.c and all calls to it
can be removed from hci_event.c.

The commands in each hci_req_sync procedure are collected into their own
request by passing the hci_request pointer to the request callback
(instead of the hci_dev pointer). The one slight exception is the HCI
init request which has the special handling of HCI driver specific
initialization commands. These commands are run in their own request
prior to the "main" init request.

One other extra change that this patch must contain is the handling of
spontaneous HCI reset complete events that some controllers exhibit.
These were previously handled in the hci_req_complete function but the
right place for them now becomes the hci_req_cmd_complete function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Remove unused hdev->init_last_cmd

This variable is no longer needed (due to async HCI request support and
the conversion of hci_req_sync to use it), so it can be safely removed.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Remove empty HCI event handlers

With the removal of hci_req_complete() several HCI event handlers have
essentially become empty and can be removed. The only potential benefit
of these could have been logging, but the hci_event, hci_cmd_complete
and hci_cmd_status already provide a log for events which they do not
have an explicit handler for.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Bluetooth: Add hci_req_deinit

This patch adds the hci_req_deinit function. This function basically
frees all HCI commands queued on a given request.

This function must be call in case something goes wrong during HCI
request creation. Otherwise, HCI commands queued on HCI request
command queue will lead us to memory leaks.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Make hci_le_scan use HCI request

This patch changes hci_le_scan helper so it uses the HCI request
framework to enable LE scanning. The LE scanning disable timeout
was removed from the helper and it is now handled by mgmt start_
discovery code.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Merge LE-only and interleaved cases

This patch merges the LE-only and interleaved discovery type cases.
Since hci_le_scan helper uses the hci request framework, those cases
are pretty much the same now.

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

This patch removes the LE scan work and all code related to it. We
now use the HCI request framework to enable LE scanning. The LE scan
work is no longer needed.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Remove timeout handling from hci_cancel_le_scan

Since LE scanning timeout is not handled by LE scanning helpers
anymore, we should handle it in stop_discovery instead of
hci_cancel_le_scan.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Change LE scanning timeout macros

Define LE scanning timeout macros in jiffies just like others timeout
macros do.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Add LE scan type macros

This patch adds macros for active and passive LE scan type values. It
also removes the LE_SCAN_TYPE macro since it is not used anymore.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Handle start discovery failure in le_scan_complete

This patch moves start discovery failure handling to le_scan_
complete callback. It also removes the LE Set Scan Parameter
HCI event handler since it becomes empty.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Bluetooth: Make hci_le_create_connection return error

This patch changes hci_le_create_connection helper so it return error
if hci_send_cmd fails. It also does the proper error handling in
hci_connect_le.

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