Re: [PATCH v1] Bluetooth: hci_qca: Add qca_power_on() API to support both wcn399x and Rome power up

[Matthias Kaehlcke <mka@chromium.org>]

Hi Rocky,

On Tue, Jan 07, 2020 at 01:26:01PM +0800, Rocky Liao wrote:
> This patch adds a unified API qca_power_on() to support both wcn399x and
> Rome power on. For wcn399x it calls the qca_wcn3990_init() to init the
> regulators, and for Rome it pulls up the bt_en GPIO to power up the btsoc.
> 
> Signed-off-by: Rocky Liao <rjliao@codeaurora.org>
> ---
>  drivers/bluetooth/hci_qca.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
> index 9392cc7f9908..f6555bd1adbc 100644
> --- a/drivers/bluetooth/hci_qca.c
> +++ b/drivers/bluetooth/hci_qca.c
> @@ -1532,6 +1532,27 @@ static int qca_wcn3990_init(struct hci_uart *hu)
>  	return 0;
>  }
>  
> +static int qca_power_on(struct hci_dev *hdev)
> +{
> +	struct hci_uart *hu = hci_get_drvdata(hdev);
> +	enum qca_btsoc_type soc_type = qca_soc_type(hu);
> +	struct qca_serdev *qcadev;
> +	int ret = 0;

another option would be to return directly from the if/else branches,
but either way is fine.

> +
> +	if (qca_is_wcn399x(soc_type)) {
> +		ret = qca_wcn3990_init(hu);
> +	} else {
> +		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);
> +		}
> +	}
> +
> +	return ret;
> +}
> +

I expected qca_power_on() would be called from qca_open(), but as is
this would only work for ROME, and not WCN399x, which only enables
the regulators in qca_open(), qca_wcn3990_init() is called from
qca_setup(). Is there a particular reason for this assymmetry between
the ROME and WCN399x initialization (i.e. one is fully powered up after
open(), the other not)?