Hi Orlando, On Fri, Oct 1, 2021 at 1:56 AM Orlando Chamberlain <redecorating@xxxxxxxxxxxxxx> wrote: > > The LE Read Transmit Power command is Advertised on some Broadcom > controlers, but not supported. Using this command breaks Bluetooth > on the MacBookPro16,1 and iMac20,1. Added a quirk disabling LE Read > Transmit Power for these devices, based off their common chip id 150. > > Link: https://lore.kernel.org/r/4970a940-211b-25d6-edab-21a815313954@xxxxxxxxxxxxxx > Signed-off-by: Orlando Chamberlain <redecorating@xxxxxxxxxxxxxx> > --- > v1->v2: Clarified quirk description > > drivers/bluetooth/btbcm.c | 4 ++++ > include/net/bluetooth/hci.h | 11 +++++++++++ > net/bluetooth/hci_core.c | 3 ++- > 3 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/drivers/bluetooth/btbcm.c b/drivers/bluetooth/btbcm.c > index e4182acee488..4ecc50d93107 100644 > --- a/drivers/bluetooth/btbcm.c > +++ b/drivers/bluetooth/btbcm.c > @@ -353,6 +353,10 @@ static int btbcm_read_info(struct hci_dev *hdev) > return PTR_ERR(skb); > > bt_dev_info(hdev, "BCM: chip id %u", skb->data[1]); > + > + if (skb->data[1] == 150) > + set_bit(HCI_QUIRK_BROKEN_READ_TRANSMIT_POWER, &hdev->quirks); > + > kfree_skb(skb); > > /* Read Controller Features */ > diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h > index b80415011dcd..6da9bd6b7259 100644 > --- a/include/net/bluetooth/hci.h > +++ b/include/net/bluetooth/hci.h > @@ -246,6 +246,17 @@ enum { > * HCI after resume. > */ > HCI_QUIRK_NO_SUSPEND_NOTIFIER, > + > + /* When this quirk is set, LE Read Transmit Power is disabled. > + * This is mainly due to the fact that the HCI LE Read Transmit > + * Power command is advertised, but not supported; these > + * controllers often reply with unknown command and need a hard > + * reset. > + * > + * 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 8a47a3017d61..9a23fe7c8d67 100644 > --- a/net/bluetooth/hci_core.c > +++ b/net/bluetooth/hci_core.c > @@ -742,7 +742,8 @@ 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)) { > /* Read LE Min/Max Tx Power*/ > hci_req_add(req, HCI_OP_LE_READ_TRANSMIT_POWER, > 0, NULL); > -- > 2.33.0 Nowadays it is possible to treat errors such like this on a per command basis (assuming it is not essential for the init sequence): diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index 979da5179ff4..f244f42cc609 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -551,6 +551,7 @@ enum { #define HCI_LK_AUTH_COMBINATION_P256 0x08 /* ---- HCI Error Codes ---- */ +#define HCI_ERROR_UNKNOWN_CMD 0x01 #define HCI_ERROR_UNKNOWN_CONN_ID 0x02 #define HCI_ERROR_AUTH_FAILURE 0x05 #define HCI_ERROR_PIN_OR_KEY_MISSING 0x06 diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index bb88d31d2212..9c697e058974 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -3325,11 +3325,18 @@ static int hci_le_read_adv_tx_power_sync(struct hci_dev *hdev) /* Read LE Min/Max Tx Power*/ static int hci_le_read_tx_power_sync(struct hci_dev *hdev) { + int status; + if (!(hdev->commands[38] & 0x80)) return 0; - return __hci_cmd_sync_status(hdev, HCI_OP_LE_READ_TRANSMIT_POWER, - 0, NULL, HCI_CMD_TIMEOUT); + status = __hci_cmd_sync_status(hdev, HCI_OP_LE_READ_TRANSMIT_POWER, + 0, NULL, HCI_CMD_TIMEOUT); + /* Ignore if command is not really supported */ + if (status == HCI_ERROR_UNKNOWN_CMD) + return 0; + + return status; } /* Read LE Accept List Size */ Anyway, it would probably be worth pointing out to the vendor they have a broken firmware if they do mark the command as supported but return such error. -- Luiz Augusto von Dentz
