Re: [PATCH v10 09/10] Bluetooth: Handle specific error for SCO connection fallback

Hi Fred,

Synchronous Connection Complete event can return error "Connection
Rejected due to Limited resources (0x10)".
Handling this error is required for SCO connection fallback. This error
happens when the server tried to accept the connection but failed to
negotiate settings.
This error code has been verified experimentally by sending a T2 request
to a T1 only SCO listener.

Client dump follows :

< HCI Command (0x01|0x0028) plen 17 [hci0] 3.696064
       Handle: 12
       Transmit bandwidth: 8000
       Receive bandwidth: 8000
       Max latency: 13
       Setting: 0x0003
       Retransmission effort: Optimize for link quality (0x02)
       Packet type: 0x0380

quoted

HCI Event (0x0f) plen 4 [hci0] 3.697034

     Setup Synchronous Connection (0x01|0x0028) ncmd 1
       Status: Success (0x00)

quoted

HCI Event (0x2c) plen 17 [hci0] 3.736059

       Status: Connection Rejected due to Limited Resources (0x0d)
       Handle: 0
       Address: xx:xx:xx:xx:xx:AB (OUI 70-F3-95)
       Link type: eSCO (0x02)
       Transmission interval: 0x0c
       Retransmission window: 0x06
       RX packet length: 60
       TX packet length: 60
       Air mode: Transparent (0x03)

Server dump follows :

quoted

HCI Event (0x04) plen 10 [hci0] 4.741513

       Address: xx:xx:xx:xx:xx:D9 (OUI 20-68-9D)
       Class: 0x620100
         Major class: Computer (desktop, notebook, PDA, organizers)
         Minor class: Uncategorized, code for device not assigned
         Networking (LAN, Ad hoc)
         Audio (Speaker, Microphone, Headset)
         Telephony (Cordless telephony, Modem, Headset)
       Link type: eSCO (0x02)
< HCI Command (0x01|0x0029) plen 21 [hci0] 4.743269
       Address: xx:xx:xx:xx:xx:D9 (OUI 20-68-9D)
       Transmit bandwidth: 8000
       Receive bandwidth: 8000
       Max latency: 13
       Setting: 0x0003
       Retransmission effort: Optimize for link quality (0x02)
       Packet type: 0x03c1

quoted

HCI Event (0x0f) plen 4 [hci0] 4.745517

     Accept Synchronous Connection (0x01|0x0029) ncmd 1
       Status: Success (0x00)

quoted

HCI Event (0x2c) plen 17 [hci0] 4.749508

       Status: Connection Rejected due to Limited Resources (0x0d)
       Handle: 0
       Address: xx:xx:xx:xx:xx:D9 (OUI 20-68-9D)
       Link type: eSCO (0x02)
       Transmission interval: 0x0c
       Retransmission window: 0x06
       RX packet length: 60
       TX packet length: 60
       Air mode: Transparent (0x03)

Signed-off-by: Frédéric Dalleau <redacted>
---
net/bluetooth/hci_event.c |    1 +
1 file changed, 1 insertion(+)

Acked-by: Marcel Holtmann <marcel@holtmann.org>

Regards

Marcel