Re: [PATCH v1] Bluetooth: hci_qca: Give enough time to ROME controller to bootup.

[rjliao]

å 2019-03-07 14:49ïBalakrishna Godavarthi åéï
> Hi Stepen,
>
> On 2019-03-07 04:03, Stephen Boyd wrote:
> > Quoting Balakrishna Godavarthi (2019-03-06 08:21:13)
> > > This patch enables enough time to ROME controller to bootup
> > > after we bring the enable ping out of reset.
> > >
> > > Signed-off-by: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx>
> > > ---
> >
> > Any Fixes tag? And maybe some more explanation or background on where
> > 150 ms sleep comes from would be useful. Was it determined
> > experimentally or did it come from a datasheet somewhere? Does the 
> > time
> > differ between boards?
> [Bala]: this was observed in our stress testing and even the CHIP 
> firmware team
>         confirmed that BT chip required at least 150 ms to boot up.
>
> @Rocky to confirm my statement.
>
> > >  drivers/bluetooth/hci_qca.c | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/drivers/bluetooth/hci_qca.c 
> > > b/drivers/bluetooth/hci_qca.c
> > > index 237aea34b69f..1953b13511e7 100644
> > > --- a/drivers/bluetooth/hci_qca.c
> > > +++ b/drivers/bluetooth/hci_qca.c
> > > @@ -508,6 +508,8 @@ static int qca_open(struct hci_uart *hu)
> > >                 qcadev = serdev_device_get_drvdata(hu->serdev);
> > >                 if (qcadev->btsoc_type != QCA_WCN3990) {
> > >                         gpiod_set_value_cansleep(qcadev->bt_en, 1);
> > > +                       /* Controller needs time to bootup. */
> > > +                       msleep(150);
> > >                 } else {
> > >                         hu->init_speed = qcadev->init_speed;
> > >                         hu->oper_speed = qcadev->oper_speed;

Hello,

Any concern to merge this change? Without this change the Rome cannot up 
while running the serdev way, we should mainline this change ASAP.