Re: [PATCH v4 3/4] Bluetooth: hci_bcm: Support pcm params in dts

From: Abhishek Pandit-Subedi
Date: Wed Nov 13 2019 - 16:22:45 EST


Hi Marcel,



On Tue, Nov 12, 2019 at 4:18 PM Marcel Holtmann <marcel@xxxxxxxxxxxx> wrote:
>
> Hi Abhishek,
>
> > BCM chips may require configuration of PCM to operate correctly and
> > there is a vendor specific HCI command to do this. Add support in the
> > hci_bcm driver to parse this from devicetree and configure the chip.
> >
> > Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
> > ---
> >
> > Changes in v4: None
> > Changes in v3: None
> > Changes in v2: None
> >
> > drivers/bluetooth/hci_bcm.c | 32 ++++++++++++++++++++++++++++++++
> > 1 file changed, 32 insertions(+)
> >
> > diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
> > index 6134bff58748..4ee0b45be7e2 100644
> > --- a/drivers/bluetooth/hci_bcm.c
> > +++ b/drivers/bluetooth/hci_bcm.c
> > @@ -88,6 +88,8 @@ struct bcm_device_data {
> > * used to disable flow control during runtime suspend and system sleep
> > * @is_suspended: whether flow control is currently disabled
> > * @disallow_set_baudrate: don't allow set_baudrate
> > + * @has_pcm_params: whether PCM parameters need to be configured
> > + * @pcm_params: PCM and routing parameters
> > */
> > struct bcm_device {
> > /* Must be the first member, hci_serdev.c expects this. */
> > @@ -122,6 +124,9 @@ struct bcm_device {
> > bool is_suspended;
> > #endif
> > bool disallow_set_baudrate;
> > +
> > + bool has_pcm_params;
> > + struct bcm_set_pcm_int_params pcm_params;
> > };
> >
> > /* generic bcm uart resources */
> > @@ -596,6 +601,16 @@ static int bcm_setup(struct hci_uart *hu)
> > host_set_baudrate(hu, speed);
> > }
> >
> > + /* PCM parameters if any*/
> > + if (bcm->dev && bcm->dev->has_pcm_params) {
> > + err = btbcm_set_pcm_int_params(hu->hdev, &bcm->dev->pcm_params);
> > +
> > + if (err) {
> > + bt_dev_info(hu->hdev, "BCM: Set pcm params failed (%d)",
> > + err);
> > + }
> > + }
> > +
> > finalize:
> > release_firmware(fw);
> >
> > @@ -1132,7 +1147,24 @@ static int bcm_acpi_probe(struct bcm_device *dev)
> >
> > static int bcm_of_probe(struct bcm_device *bdev)
> > {
> > + int err;
> > +
> > device_property_read_u32(bdev->dev, "max-speed", &bdev->oper_speed);
> > +
> > + err = device_property_read_u8(bdev->dev, "brcm,bt-sco-routing",
> > + &bdev->pcm_params.routing);
> > + if (!err)
> > + bdev->has_pcm_params = true;
>
> I think in case of HCI as routing path, these should be using the default or zero values as defined by Broadcom.

I'm not sure what these default values should be. Wouldn't it be
reasonable to expect the user/developer to set the various brcm
parameters in device tree?
If unset, it's just 0.

>
> > +
> > + device_property_read_u8(bdev->dev, "brcm,pcm-interface-rate",
> > + &bdev->pcm_params.rate);
> > + device_property_read_u8(bdev->dev, "brcm,pcm-frame-type",
> > + &bdev->pcm_params.frame_sync);
> > + device_property_read_u8(bdev->dev, "brcm,pcm-sync-mode",
> > + &bdev->pcm_params.sync_mode);
> > + device_property_read_u8(bdev->dev, "brcm,pcm-clock-mode",
> > + &bdev->pcm_params.clock_mode);
> > +
>
> I would add some sanity checks here.
>
> Regards
>
> Marcel
>