Re: [PATCH v1] Bluetooth: hci_qca: Enable the ldisc for ROME for x86 platforms.

[rjliao]

å 2019-03-12 23:52ïMatthias Kaehlcke åéï
> Hi Rocky,
>
> On Tue, Mar 12, 2019 at 05:01:59PM +0800, rjliao@xxxxxxxxxxxxxx wrote:
> > å 2019-03-09 02:52ïMatthias Kaehlcke åéï
> > > On Fri, Mar 08, 2019 at 10:43:14AM +0530, Balakrishna Godavarthi wrote:
> > > > Hi Matthias,
> > > >
> > > > On 2019-03-08 02:12, Matthias Kaehlcke wrote:
> > > > > Hi Balakrishna,
> > > > >
> > > > > On Thu, Mar 07, 2019 at 03:47:22PM +0530, Balakrishna Godavarthi wrote:
> > > > > > When using btattach to setup Rome over ldisc we observed a crash
> > > > > > in qca_setup as it will try to access the serdev which is not
> > > > > > available in the ldisc proto. This patch will fix the crash by
> > > > > > support both the ldisc and serdev way in the qca hci_uart driver.
> > > > > >
> > > > > > Signed-off-by: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx>
> > > > >
> > > > > Oh, I wasn't aware of the instantiation through ldisc and was actually
> > > > > considering to *remove* some of the seemingly unnecessary serdev
> > > > > checks.
> > > > >
> > > > > > ---
> > > > > >  drivers/bluetooth/hci_qca.c | 47
> > > > > > ++++++++++++++++++++++---------------
> > > > > >  1 file changed, 28 insertions(+), 19 deletions(-)
> > > > > >
> > > > > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
> > > > > > index 237aea34b69f..0a5c98d46864 100644
> > > > > > --- a/drivers/bluetooth/hci_qca.c
> > > > > > +++ b/drivers/bluetooth/hci_qca.c
> > > > > > @@ -963,7 +963,7 @@ static int qca_set_baudrate(struct hci_dev
> > > > > > *hdev, uint8_t baudrate)
> > > > > >  {
> > > > > >  	struct hci_uart *hu = hci_get_drvdata(hdev);
> > > > > >  	struct qca_data *qca = hu->priv;
> > > > > > -	struct qca_serdev *qcadev;
> > > > > > +	struct qca_serdev *qcadev = NULL;
> > > > >
> > > > > In many cases the only field that is accessed is qcadev->btsoc_type. I
> > > > > think something like 'qca_get_soc_type(struct hci_dev *hdev / struct
> > > > > hci_uart *hu)' would make things more readable.
> > > > >
> > > > [Bala]: sure will update this in other patch once this change is
> > > > landed as
> > > > this has to
> > > >         go in priority as we have crash coming.
> > >
> > > That's not how things should work, especially for fairly trivial
> > > changes. It requires reviewers to first spent time to review the patch
> > > that adds clutter and later spend more time to review the one that
> > > removes it. It's also easier to get a clean patch merged in the first
> > > place, rather than a noisy one.
> > >
> > > Anyway, here is my take at it:
> > > https://lore.kernel.org/patchwork/patch/1049014/
> > >
> > > Please help with testing for ROME, unless you disagree with the
> > > approach.
> > >
> > > Thanks
> > >
> > > Matthias
> >
> > Hi Matthias,
> >
> > I will test your patch and update to you, and you are correct that 
> > AR3002 is
> > not part of Rome family, you should use QCA_ROME as the default return 
> > of
> > qca_soc_type.
>
> Thanks for the confirmation!
>
> > Could you also loop me in
> > https://lore.kernel.org/patchwork/patch/1049014/?
>
> This patch has been superseded by a newer version:
>
> https://lore.kernel.org/patchwork/patch/1049696/
>
> It already landed in bluetooth-next.
>
> Testing with Rome and ldisc would still be appreciated, since I don't
> have such a configuration.
>
> Thanks
>
> Matthias

Hi Matthias,

I verified your change and found there is another deference to serdev in 
the qca_set_baudrate() function while running the ldisc proto, it will 
cause a crash and need to add a check as below. Could you help to add 
this change?

<       serdev_device_wait_until_sent(hu->serdev,
<                       msecs_to_jiffies(CMD_TRANS_TIMEOUT_MS));
---
>       if (hu->serdev)
>               serdev_device_wait_until_sent(hu->serdev,
>                               msecs_to_jiffies(CMD_TRANS_TIMEOUT_MS));