Hi Sergey,
> The MediaTek Bluetooth platform (MT6630 etc.) has a peculiar implementation
> for the eSCO/SCO connection via BT/EDR: the host controller returns error
> code 0x20 (LMP feature not supported) for HCI_Setup_Synchronous_Connection
> (0x0028) command without actually trying to setup connection with a remote
> device in case such device (like Digma BT-14 headset) didn't advertise its
> supported features. Even though this doesn't break compatibility with the
> Bluetooth standard it breaks the compatibility with the Hands-Free Profile
> (HFP).
>
> This patch returns the compatibility with the HFP profile and actually
> tries to check all available connection parameters despite of the specific
> MediaTek implementation. Without it one was unable to establish eSCO/SCO
> connection with some headsets.
please include the parts of btmon output that show this issue.
> Based on the patch by Ildar Kamaletdinov <i.kamaletdinov@xxxxxxxxxxxx>.
>
> Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxxxxxxxx>
>
> ---
> This patch is against the 'bluetooth-next.git' repo.
>
> net/bluetooth/hci_event.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> Index: bluetooth-next/net/bluetooth/hci_event.c
> ===================================================================
> --- bluetooth-next.orig/net/bluetooth/hci_event.c
> +++ bluetooth-next/net/bluetooth/hci_event.c
> @@ -2187,6 +2187,13 @@ static void hci_cs_setup_sync_conn(struc
> if (acl) {
> sco = acl->link;
> if (sco) {
> + if (status == 0x20 && /* Unsupported LMP Parameter value */
> + sco->out) {
> + sco->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
> + (hdev->esco_type & EDR_ESCO_MASK);
> + if (hci_setup_sync(sco, sco->link->handle))
> + goto unlock;
> + }
> sco->state = BT_CLOSED;
since this is the command status event, I doubt that sco->out check is needed. And I would start with a switch statement right away.
I also think that we need to re-structure this hci_cs_setup_sync_conn function a little to avoid the deep indentation. Make it look more like hci_sync_conn_complete_evt also use a switch statement even if right now we only have one entry.
Regards
Marcel
