Re: [PATCH v3 1/2] Bluetooth: add quirk disabling LE Read Transmit Power

From: Marcel Holtmann
Date: Mon Nov 29 2021 - 06:04:35 EST


Hi Aditya,

> Some devices have a bug causing them to not work if they query
> LE tx power on startup. Thus we add a quirk in order to not query it
> and default min/max tx power values to HCI_TX_POWER_INVALID.
>
> Signed-off-by: Aditya Garg <gargaditya08@xxxxxxxx>
> ---
> include/net/bluetooth/hci.h | 9 +++++++++
> net/bluetooth/hci_core.c | 3 ++-
> 2 files changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index 63065bc01b766c..383342efcdc464 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -246,6 +246,15 @@ enum {
> * HCI after resume.
> */
> HCI_QUIRK_NO_SUSPEND_NOTIFIER,
> +
> + /*
> + * When this quirk is set, LE tx power is not queried on startup
> + * and the min/max tx power values default to HCI_TX_POWER_INVALID.
> + *
> + * This quirk can be set before hci_register_dev is called or
> + * during the hdev->setup vendor callback.
> + */
> + HCI_QUIRK_BROKEN_READ_TRANSMIT_POWER,
> };
>
> /* HCI device flags */
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 8d33aa64846b1c..434c6878fe9640 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -619,7 +619,8 @@ static int hci_init3_req(struct hci_request *req, unsigned long opt)
> hci_req_add(req, HCI_OP_LE_READ_ADV_TX_POWER, 0, NULL);
> }
>
> - if (hdev->commands[38] & 0x80) {
> + if (hdev->commands[38] & 0x80 &&
> + !test_bit(HCI_QUIRK_BROKEN_READ_TRANSMIT_POWER, &hdev->quirks)) {

if ((hdev->commands[38] && 0x80) &&
!test_bit(HCI_QUIRK_.., &hdev->quirks)) {

> /* Read LE Min/Max Tx Power*/
> hci_req_add(req, HCI_OP_LE_READ_TRANSMIT_POWER,
> 0, NULL);
>

Regards

Marcel