On Thu, 18 Apr 2024 at 16:06, Zijun Hu <quic_zijuhu@xxxxxxxxxxx> wrote:
>
> This reverts commit 56d074d26c5828773b00b2185dd7e1d08273b8e8.
>
> Commit 56d074d26c58 ("Bluetooth: hci_qca: don't use IS_ERR_OR_NULL()
> with gpiod_get_optional()") will cause serious regression issue for
> several QCA controllers such as QCA_WCN6750,QCA_WCN6855,QCA_ROME,
> QCA_QCA6390 and QCA_QCA2066, the regression issue is that BT can't be
> enabled any more once BT is disabled if BT reset pin is not configured
> by DT or ACPI.
>
> if BT reset pin is not configured, devm_gpiod_get_optional() will return
> NULL, and we should NOT set quirk HCI_QUIRK_NON_PERSISTENT_SETUP, but the
> reverted commit SET the quirk since NULL is not a error case, and cause
> qca_setup() call failure triggered by the 2nd and later BT enable
> operations since there are no available BT reset pin to clear BT firmware
> downloaded by the 1st enable operation, fixed by reverting the commit.
>
> Fixes: 56d074d26c58 ("Bluetooth: hci_qca: don't use IS_ERR_OR_NULL() with gpiod_get_optional()")
> Reported-by: Wren Turkal <wt@xxxxxxxxxxxxxxxx>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=218726
> Link: https://lore.kernel.org/linux-bluetooth/ea20bb9b-6b60-47fc-ae42-5eed918ad7b4@xxxxxxxxxxx/T/#m73d6a71d2f454bb03588c66f3ef7912274d37c6f
> Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
> Tested-by: Wren Turkal <wt@xxxxxxxxxxxxxxxx>
> ---
> drivers/bluetooth/hci_qca.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
> index 92fa20f5ac7d..160175a23a49 100644
> --- a/drivers/bluetooth/hci_qca.c
> +++ b/drivers/bluetooth/hci_qca.c
> @@ -2323,7 +2323,7 @@ static int qca_serdev_probe(struct serdev_device *serdev)
>
> qcadev->bt_en = devm_gpiod_get_optional(&serdev->dev, "enable",
> GPIOD_OUT_LOW);
> - if (IS_ERR(qcadev->bt_en) &&
> + if (IS_ERR_OR_NULL(qcadev->bt_en) &&
> (data->soc_type == QCA_WCN6750 ||
> data->soc_type == QCA_WCN6855)) {
> dev_err(&serdev->dev, "failed to acquire BT_EN gpio\n");
> @@ -2332,7 +2332,7 @@ static int qca_serdev_probe(struct serdev_device *serdev)
>
> qcadev->sw_ctrl = devm_gpiod_get_optional(&serdev->dev, "swctrl",
> GPIOD_IN);
> - if (IS_ERR(qcadev->sw_ctrl) &&
> + if (IS_ERR_OR_NULL(qcadev->sw_ctrl) &&
> (data->soc_type == QCA_WCN6750 ||
> data->soc_type == QCA_WCN6855 ||
> data->soc_type == QCA_WCN7850))
> @@ -2354,7 +2354,7 @@ static int qca_serdev_probe(struct serdev_device *serdev)
> default:
> qcadev->bt_en = devm_gpiod_get_optional(&serdev->dev, "enable",
> GPIOD_OUT_LOW);
> - if (IS_ERR(qcadev->bt_en)) {
> + if (IS_ERR_OR_NULL(qcadev->bt_en)) {
> dev_warn(&serdev->dev, "failed to acquire enable gpio\n");
> power_ctrl_enabled = false;
> }
> --
> 2.7.4
>
I told you under your yesterday's submission that you should instead
consider bailing out from probe() if gpiod_get_optional() returns an
error as right now if it returns EPROBE_DEFER (enable-gpios is there
but the controller is not up yet), you will act like the GPIO was not
even specified.
gpiod_get_optional() returns NULL if the GPIO property is not there or
an error if anything else goes wrong. In the latter case, you should
abort probe.
Bart
