Hi Marcel,
On Thu, Apr 5, 2012 at 9:44 PM, Marcel Holtmann <marcel@xxxxxxxxxxxx> wrote:
> Hi Hemant,
>
>> > This patch uses the corect packet type for ESCO Link.
>> > Without this patch esco packet types were anded with ~EDR_ESCO_MASK
>> > resulting in setting bits that are not supported by controller
>> > to 0 which means that corresponding EDR ESCO packet type is
>> > supported(EDR Packet types are inverted as per BT Spec) which might
>> > not be the case.
>> >
>> Any comments on this patch ?
>
> as I said before, I like to see a hcidump in the commit messages that
> shows the failure.
>
I am not sure the hcidump would indicate the exact problem, because the problem
is of selecting wrong eSCO edr pkt type of local device and moreover
my code base is bit different from upstream code.
For eg:
Local Controller supports only 3-EV5, 2-EV5 and 3-EV3 of the EDR eSCO packet
types and does not support 2-EV3 packet type.
This would mean that while creating the esco_type in function
hci_cc_read_local_features()
the ESCO_2EV3 bit would not be set and all other EDR eSCO bits would be set.
Resulting hdev->esco_type = 0x0380
Now in hci_conn_add() when the pkt_type is being calculated for eSCO
Link, wrong calculation
would take place as below:
conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
= 0x0380 & ~0x03C0 = 0x0380 & 0xFC3F = 0x0000
Since the EDR eSCO bits are invertedThis indicates that ultimately all
EDR eSCO packet types are supported, which is not correct as local
controller is not supporting the 2-EV3 packet type.
As per calculations of the patch
conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
= 0x0380 ^ 0x03C0 = 0x0040
which correctly indicates that packet type used excludes the 2-EV3
packet type not supported by local controller.
Please let me know your views on this.
> Regards
>
> Marcel
>
>
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--
Best Regards
Hemant Gupta
ST-Ericsson India
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