Hi Marcel,
On 2018-11-14 13:18, Marcel Holtmann wrote:
Hi Balakrishna,
During hci down we are sending reset command to chip, which
is not required for wcn3990, as hdev->shutdown() will turn off
the
regulators.
Signed-off-by: Balakrishna Godavarthi <bgoda...@codeaurora.org>
---
drivers/bluetooth/hci_qca.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/bluetooth/hci_qca.c
b/drivers/bluetooth/hci_qca.c
index 8301663f0004..97b57e0f4725 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -1190,6 +1190,7 @@ static int qca_setup(struct hci_uart *hu)
*/
set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
set_bit(HCI_QUIRK_USE_BDADDR_PROPERTY, &hdev->quirks);
+ clear_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
hu->hdev->shutdown = qca_power_off;
ret = qca_wcn3990_init(hu);
if (ret)
I am pretty certain that you didn’t want this quirk:
/* When this quirk is set, the HCI Reset command is send
when
* closing the transport instead of when opening it.
This quirk is for Bluetooth 1.0b devices where the HCI_Reset
behavior
was not clear or for devices that actually misbehave with the
initial
HCI_Reset.
In addition, you commit message is totally misleading. That is not
what is happening with this quirk.
Regards
Marcel
My intention was reset command is not required when we do an hci
down.
this is because of hdev->shutdown will turn off the regulators.
It is like turning off the chip. sending reset command after
turning off the chip is not required.
I understand the usage of the quirk, will update the commit text.
you are papering over the issue. Actually
hci_serdev.c:hci_uart_register_device() is the culprit with the
legacy
code copied over from hci_ldisc.c:hci_uart_register_dev(). I think
there is no point doing all this legacy line discipline quirk
handling
until it is really needed. The serdev drivers are all for recent
hardware.
That said, having moved over to a btuart.c approach and killed the
whole hci_serdev.c thing would have been a lot better here. You will
keep running in weird situations where 18 year old code keeps
surprising you.
[Bala]: even i feel the same. they are lot such kind of HACK's we
need
to do with current arch.
when can we expect btuart.c merged to bt-next. i think having
btuart will helps us to have the control of
vendor porto's call's like in btusb.c
Regards
Marcel
I need some clarification, do you expect some thing like this
https://github.com/torvalds/linux/blob/master/drivers/bluetooth/btmtkuart.c
for Qualcomm BT chip too.
it looks it is completely avoided hci_serdev.c interface.
you tell me actually. Are you using the H:4 transport or do you have
an extra protocol layer / framing below it. If you do, then use your
own driver, but if the transport is H:4 with vendor packets and vendor
setup, then btuart.c (which is not yet upstream) should be your
target.
For the MTK hardware it was obvious that it was better served as a
separate driver. For QCA serial it really depends on how much extra
protocol you have to run. So this might be an exercise in trying QCA
serial as a separate driver and then go from there.
It is clear that the baggage from hci_ldisc.c etc is in the way for
serdev based systems.
Regards
Marcel
[Bala]:
From my experience of serdev and ldisc, I prefer to go as MTK, here
are the reasons
1.If btuart maintains same generic way as hci_serdev, hardware
vendors will not have control on of
port opening and close. Because qca want to close port when we do
hci down where as hci_serdev it is not possible to do.
This is an important feature for power saving of the device.
2. I think btuart will have common recv_handle to handle all the
received data irrespective to the vendors.
but in our case, we will receive debug logs as ACL packet which
is not possible to bypass as diagnostic packet.
The same with the susb system restart events too. So, I feel that
having an different driver as same as MTK will help us.
--
Regards
Balakrishna.
