Re: [PATCH v1] Bluetooth: hci_qca: disable power control for WCN7850 when bt_en is not defined

[Dmitry Baryshkov]

On Thu, Mar 19, 2026 at 02:06:49PM +0800, Shuai Zhang wrote:
> 
> On 3/19/2026 1:42 PM, Dmitry Baryshkov wrote:
> > On Thu, Mar 19, 2026 at 01:21:58PM +0800, Shuai Zhang wrote:
> > > Hi  Dmitry
> > > 
> > > On 3/19/2026 11:51 AM, Dmitry Baryshkov wrote:
> > > > On Thu, Mar 19, 2026 at 11:10:40AM +0800, Shuai Zhang wrote:
> > > > > For platforms where the bt_en GPIO is not defined, software-based power
> > > > > control should be disabled when power is managed by hardware.
> > > > What does it mean for this chip, managing the power in hardware?
> > > bt_en is pulled high by hardware,
> > In which cases is it applicable?
> 
> 
> On platforms using an M.2 slot with both UART and USB support, bt_en is
> pulled high
> 
> by hardware. The current platforms are Lemans‑EVK and Monaco‑EVK.

This needs to be a part of the commit message.

> 
> 
> > 
> > > or described in the device tree as a
> > > regular always-on GPIO.
> > Why?
> 
> 
> This is equivalent to bt_en being pulled high by hardware,
> 
> and it applies to the same scenarios and platforms mentioned above.

No, DT would not describe the GPIO as always-on in this case.

> 
> 
> > 
> > > 
> > > > > Add QCA_WCN7850 to the existing condition so that power_ctrl_enabled is
> > > > > cleared when bt_en is absent, aligning its behavior with WCN6750 and
> > > > > WCN6855.
> > > > > 
> > > > > Signed-off-by: Shuai Zhang <shuai.zhang@xxxxxxxxxxxxxxxx>
> > > > > ---
> > > > >    drivers/bluetooth/hci_qca.c | 3 ++-
> > > > >    1 file changed, 2 insertions(+), 1 deletion(-)
> > > > > 
> > > > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
> > > > > index c17a462aef55..4512ff7cd0c0 100644
> > > > > --- a/drivers/bluetooth/hci_qca.c
> > > > > +++ b/drivers/bluetooth/hci_qca.c
> > > > > @@ -2484,7 +2484,8 @@ static int qca_serdev_probe(struct serdev_device *serdev)
> > > > >    		if (!qcadev->bt_en &&
> > > > >    		    (data->soc_type == QCA_WCN6750 ||
> > > > > -		     data->soc_type == QCA_WCN6855))
> > > > > +		     data->soc_type == QCA_WCN6855 ||
> > > > > +		     data->soc_type == QCA_WCN7850))
> > > > >    			power_ctrl_enabled = false;
> > > > >    		qcadev->sw_ctrl = devm_gpiod_get_optional(&serdev->dev, "swctrl",
> > > > > -- 
> > > > > 2.34.1
> > > > > 

-- 
With best wishes
Dmitry