Re: [PATCH v3 2/4] Bluetooth: hci_qca: Retry btsoc initialize when it fails

[rjliao]

å 2020-01-03 02:41ïMatthias Kaehlcke åéï

> Hi Rocky,
>
> On Fri, Dec 27, 2019 at 03:21:28PM +0800, Rocky Liao wrote:
>
> > This patch adds the retry of btsoc initialization when it fails. There 
> > are
> > reports that the btsoc initialization may fail on some platforms but 
> > the
> > repro ratio is very low. The failure may be caused by UART, platform 
> > HW or
> > the btsoc itself but it's very difficlut to root cause, given the 
> > repro
> > ratio is very low. Add a retry for the btsoc initialization will 
> > resolve
> > most of the failures and make Bluetooth finally works.
>
> Is this problem specific to a certain chipset?
>
> What are the symptoms?

It's reported on Rome so far but I think the patch is potentially 
helpful for
wcn399x as well.

The symptoms is the firmware downloading failed due to the UART write 
timed out.

> > Signed-off-by: Rocky Liao <rjliao@xxxxxxxxxxxxxx>
> > ---
> >
> > Changes in v2: None
> > Changes in v3: None
> >
> > drivers/bluetooth/hci_qca.c | 26 ++++++++++++++++++++++++++
> > 1 file changed, 26 insertions(+)
> >
> > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
> > index 43fd84028786..45042aa27fa4 100644
> > --- a/drivers/bluetooth/hci_qca.c
> > +++ b/drivers/bluetooth/hci_qca.c
> > @@ -53,6 +53,9 @@
> > /* Controller debug log header */
> > #define QCA_DEBUG_HANDLE    0x2EDC
> >
> > +/* max retry count when init fails */
> > +#define QCA_MAX_INIT_RETRY_COUNT 3
>
> nit: MAX_RETRIES or MAX_INIT_RETRIES?
>
> The QCA prefix just adds noise here IMO, there's no need to 
> disambiguate
> the constant from other retries since it is defined in hci_qca.c.
>
> > +
> > enum qca_flags {
> > QCA_IBS_ENABLED,
> > QCA_DROP_VENDOR_EVENT,
> > @@ -1257,7 +1260,9 @@ static int qca_setup(struct hci_uart *hu)
> > {
> > struct hci_dev *hdev = hu->hdev;
> > struct qca_data *qca = hu->priv;
> > +    struct qca_serdev *qcadev;
> > unsigned int speed, qca_baudrate = QCA_BAUDRATE_115200;
> > +    unsigned int init_retry_count = 0;
>
> nit: the name is a bit clunky, how about 'retries'?
>
> > enum qca_btsoc_type soc_type = qca_soc_type(hu);
> > const char *firmware_name = qca_get_firmware_name(hu);
> > int ret;
> > @@ -1275,6 +1280,7 @@ static int qca_setup(struct hci_uart *hu)
> > */
> > set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
> >
> > +retry:
> > if (qca_is_wcn399x(soc_type)) {
> > bt_dev_info(hdev, "setting up wcn3990");
> >
> > @@ -1293,6 +1299,12 @@ static int qca_setup(struct hci_uart *hu)
> > return ret;
> > } else {
> > bt_dev_info(hdev, "ROME setup");
> > +        if (hu->serdev) {
> > +            qcadev = serdev_device_get_drvdata(hu->serdev);
> > +            gpiod_set_value_cansleep(qcadev->bt_en, 1);
> > +            /* Controller needs time to bootup. */
> > +            msleep(150);
>
> Shouldn't this be in qca_power_on(), analogous to the power off code 
> from
> "[1/4]Bluetooth: hci_qca: Add QCA Rome power off support to the
> qca_power_off()"?
>
> qca_power_on() should then also be called for ROME. If you opt for this 
> it
> should be done in a separate patch, or possibly merged into the one
> mentioned above.

There is no qca_power_on() func and wcn399x is calling 
qca_wcn3990_init() to
do power on, I prefer to not do this change this time. If it's needed it 
should
be a new patch to add qca_power_on() which supports both Rome and 
wcn399x.

> > +        }
> > qca_set_speed(hu, QCA_INIT_SPEED);
> > }
> >
> > @@ -1329,6 +1341,20 @@ static int qca_setup(struct hci_uart *hu)
> > * patch/nvm-config is found, so run with original fw/config.
> > */
> > ret = 0;
> > +    } else {
> > +        if (init_retry_count < QCA_MAX_INIT_RETRY_COUNT) {
> > +            qca_power_off(hdev);
> > +            if (hu->serdev) {
> > +                serdev_device_close(hu->serdev);
> > +                ret = serdev_device_open(hu->serdev);
> > +                if (ret) {
> > +                    bt_dev_err(hu->hdev, "open port fail");
>
> nit: "failed to open port"