Re: [PATCHv2 1/1] bluetooth: Check for SCO type before setting retransmission effort
From: Marcel Holtmann <marcel@holtmann.org>
Date: 2014-09-18 15:47:55
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Hi Bernhard,
quoted hunk ↗ jump to hunk
SCO connection cannot be setup to devices that do not support retransmission. Patch based on http://permalink.gmane.org/gmane.linux.bluez.kernel/7779 and adapted for this kernel version. Code changed to check SCO/eSCO type before setting retransmission effort and max. latency. The purpose of the patch is to support older devices not capable of eSCO. Tested on Blackberry 655+ headset which does not support retransmission. Credits go to Alexander Sommerhuber. Signed-off-by: Bernhard Thaler <redacted> --- net/bluetooth/hci_conn.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index faff624..f6e3183 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c@@ -194,10 +194,18 @@ bool hci_setup_sync(struct hci_conn *conn, __u16 handle)param = &sco_param_wideband[conn->attempt - 1]; break; case SCO_AIRMODE_CVSD: - if (conn->attempt > ARRAY_SIZE(sco_param_cvsd)) - return false; - cp.retrans_effort = 0x01; - param = &sco_param_cvsd[conn->attempt - 1]; + if (!lmp_esco_capable(conn->link)) { + /* sco_param_cvsd contains SCO in last two elements */ + if ((conn->attempt + 3) > ARRAY_SIZE(sco_param_cvsd)) + return false; + cp.retrans_effort = 0xff; + param = &sco_param_cvsd[(conn->attempt + 2)];
so if anybody creates a new mode and forgets to update this code, we are hitting a nice crash and/or wrong behavior. I would prefer that we create separate parameter arrays here. It might means that we have to rename the current ones to esco_param_* and the introduce sco_param_cvsd.
+ } else {
+ if (conn->attempt > ARRAY_SIZE(sco_param_cvsd))
+ return false;
+ cp.retrans_effort = 0x01;
+ param = &sco_param_cvsd[conn->attempt - 1];
+ }
break;
default:
return false;Regards Marcel