On 4/18/2024 2:59 AM, Bartosz Golaszewski wrote:
> On Wed, 17 Apr 2024 at 13:53, 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.
>>
>
> Then you just go back to bad usage of the GPIO API. Please see my
> suggestion below.
>
we need to treat below tow cases equivalently.
1) BT reset pin is NOT configured, devm_gpiod_get_optional() return NULL.
2) BT reset pin is configured, but failed to be got, devm_gpiod_get_optional() return ERROR.
FOR above two cases, hci_qca driver doesn't get available BT reset pin for H/W reset.
so we use IS_ERR_OR_NULL() instead of IS_ERR().
is it not right ?
>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=218726
>> Fixes: 56d074d26c58 ("Bluetooth: hci_qca: don't use IS_ERR_OR_NULL() with gpiod_get_optional()")
>> Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
>> ---
>> 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;
>
> Can you just move this out of this block? Or just simply check the
> presence of the GPIO descriptor in the if block setting the quirk bit?
> Warning on a missing *optional* GPIO is wrong. It's not an unexpected
> situation, it's normal.
>
your concern is that the prompt message is printed by wrong way or the prompt message is not precise.
is it right ?
> Bartosz
>
>> }
>> --
>> 2.7.4
>>
