Re: [PATCH v6 08/11] Bluetooth: hci_qca: Support QCA2066 on M.2 connector via pwrseq

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Early return in `qca_power_off()` skips GPIO de-assertion for default branch devices with a power sequencer.
--

commit 6c86f185e6dc88f0462c04e46b64a4f809caeae3
Author: Loic Poulain <loic.poulain@oss.qualcomm.com>

Bluetooth: hci_qca: Support QCA2066 on M.2 connector via pwrseq
    
For QCA2066 (and other QCA chips) on M.2 connectors, the UART enable is
controlled by the W_DISABLE2# signal managed by the pcie-m2 power sequencer
rather than a dedicated BT enable GPIO.
    
When the serdev controller has an OF graph (indicating it is connected to
an M.2 connector), acquire the uart pwrseq target from the connector's
power sequencer and use it to control BT power instead of the bt-enable
GPIO. This is factored out into qca_serdev_get_m2_pwrseq().

> diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
> index 30586120c4a73..db0a968dfb00f 100644
> --- a/drivers/bluetooth/hci_qca.c
> +++ b/drivers/bluetooth/hci_qca.c
> @@ -1875,6 +1875,9 @@ static int qca_power_on(struct hci_dev *hdev)
>  			/* Controller needs time to bootup. */
>  			msleep(150);
>  		}
> +
> +		if (qcadev->bt_power.pwrseq)
> +			pwrseq_power_on(qcadev->bt_power.pwrseq);
>  	}
>  
>  	clear_bit(QCA_BT_OFF, &qca->flags);

[Severity: Medium]
For devices in the default switch case, if the device tree contains both an
enable GPIO and an M.2 power sequencer, qca_serdev_probe() will acquire both.
This block asserts the enable GPIO and then turns on the power sequencer.

However, in qca_power_off(), the presence of a power sequencer causes an early
return:

drivers/bluetooth/hci_qca.c:qca_power_off() {
    ...
	if (power->pwrseq) {
		pwrseq_disable(power->pwrseq);
		set_bit(QCA_BT_OFF, &qca->flags);
		return;
	}

	switch (soc_type) {
    ...
	default:
		gpiod_set_value_cansleep(qcadev->bt_en, 0);
	}
    ...
}

Will this early return cause the enable GPIO to be left asserted indefinitely
upon power off for these devices?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260904-monza-wireless-v6-0-d8c5042b3efd@oss.qualcomm.com?part=8