Return-Path: Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 7.0 \(1816\)) Subject: Re: [RFC v2 10/15] Bluetooth: Temporarily stop background scanning on discovery From: Marcel Holtmann In-Reply-To: <1383053160-10175-11-git-send-email-andre.guedes@openbossa.org> Date: Wed, 30 Oct 2013 00:19:18 +0100 Cc: "linux-bluetooth@vger.kernel.org development" Message-Id: <8E33B37F-71D9-4516-8883-080DDEC81132@holtmann.org> References: <1383053160-10175-1-git-send-email-andre.guedes@openbossa.org> <1383053160-10175-11-git-send-email-andre.guedes@openbossa.org> To: Andre Guedes Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Andre, > If the user send a mgmt start discovery command while the background > scanning is running, we should temporarily stop it. Once the discovery > finishes, we start the background scanning again. > > Signed-off-by: Andre Guedes > --- > net/bluetooth/hci_core.c | 5 +++++ > net/bluetooth/mgmt.c | 12 ++++++++---- > 2 files changed, 13 insertions(+), 4 deletions(-) > > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c > index 79debc3..44d3f99 100644 > --- a/net/bluetooth/hci_core.c > +++ b/net/bluetooth/hci_core.c > @@ -1496,6 +1496,11 @@ void hci_discovery_set_state(struct hci_dev *hdev, int state) > > switch (state) { > case DISCOVERY_STOPPED: > + /* Check the background scanning since it may have been > + * temporarily stopped by the start discovery command. > + */ > + hci_check_background_scan(hdev); > + I do not know what check here means. For me this is reenable_background_scan or trigger_background_scan or start_background_scan, but not some magic check. > if (hdev->discovery.state != DISCOVERY_STARTING) > mgmt_discovering(hdev, 0); > break; > diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c > index 22cf547..0e329e5 100644 > --- a/net/bluetooth/mgmt.c > +++ b/net/bluetooth/mgmt.c > @@ -3280,11 +3280,15 @@ static int start_discovery(struct sock *sk, struct hci_dev *hdev, > goto failed; > } > > + /* If controller is scanning, it means the background scanning > + * is running. Thus, we should temporarily stop it in order to > + * set the discovery scanning parameters. > + */ > if (test_bit(HCI_LE_SCAN, &hdev->dev_flags)) { > - err = cmd_status(sk, hdev->id, MGMT_OP_START_DISCOVERY, > - MGMT_STATUS_BUSY); > - mgmt_pending_remove(cmd); > - goto failed; > + memset(&enable_cp, 0, sizeof(enable_cp)); > + enable_cp.enable = LE_SCAN_DISABLE; > + hci_req_add(&req, HCI_OP_LE_SET_SCAN_ENABLE, > + sizeof(enable_cp), &enable_cp); > } I think we need a new hdev->dev_flags for HCI_LE_BG_SCAN. Magically assuming that it is a background scan is dangerous. Regards Marcel