Re: eSCO or SCO link?

Hi All,

2009/3/31 Nick Pelly [off-list ref]:

2009/3/30 卞磊 [off-list ref]:

quoted

Hi All,
 I made a mistake when writing the email, I have not complete my question.

2009/3/31 卞磊 [off-list ref]:

quoted

Hi All,
 I have a stlc2500c which is a Bluetooth 1.2 chip. When debuging
function 'hci_connect', i found the hci link type of the arguments was
SCO_LINK, because i enabled 'lmp_esco_capable' in my kernel, it call
'hci_setup_sync' to setup eSCO link.

But when i check connection by 'hcitool con', the hcitool show it was
a SCO link. So, is it a SCO link or eSCO link? Thanks.

hcitool con will report eSCO if it is eSCO, so you have a SCO link.

hci_setup_sync can be used for both SCO and eSCO, and the chipset
and/or the host stack will fall back to SCO if eSCO parameters can not
be negotiated. An LMP log will show why.

Maybe the function 'hci_sync_conn_complete_evt' matches what you said.

static inline void hci_sync_conn_complete_evt(struct hci_dev *hdev,
struct sk_buff *skb)
{
       ...
	printk("hci_sync_conn_complete_evt, ev->link_type=%d\n",
ev->link_type); ------> ev->link_type=0
	
	conn = hci_conn_hash_lookup_ba(hdev, ev->link_type, &ev->bdaddr);

	printk("hci_sync_conn_complete_evt, conn=%p\n",
conn);-------------------------------> conn=00000000
	
	if (!conn) {
		if (ev->link_type == ESCO_LINK)
			goto unlock;

		conn = hci_conn_hash_lookup_ba(hdev, ESCO_LINK, &ev->bdaddr);
		if (!conn)
			goto unlock;

		conn->type = SCO_LINK;----------------------------------------------------------------------->
fall back to SCO?
	}
        ...
}

Nick

LeiBian
BR