[PATCH 6.0 0976/1073] Bluetooth: Add quirk to disable extended scanning

Greg Kroah-Hartman
2022-12-28T16:49:58Z

From: Sven Peter <sven@svenpeter.dev>

[ Upstream commit 392fca352c7a95e2828d49e7500e26d0c87ca265 ]

Broadcom 4377 controllers found in Apple x86 Macs with the T2 chip
claim to support extended scanning when querying supported states,

< HCI Command: LE Read Supported St.. (0x08|0x001c) plen 0
> HCI Event: Command Complete (0x0e) plen 12
LE Read Supported States (0x08|0x001c) ncmd 1
Status: Success (0x00)
States: 0x000003ffffffffff
[...]
LE Set Extended Scan Parameters (Octet 37 - Bit 5)
LE Set Extended Scan Enable (Octet 37 - Bit 6)
[...]

, but then fail to actually implement the extended scanning:

< HCI Command: LE Set Extended Sca.. (0x08|0x0041) plen 8
Own address type: Random (0x01)
Filter policy: Accept all advertisement (0x00)
PHYs: 0x01
Entry 0: LE 1M
Type: Active (0x01)
Interval: 11.250 msec (0x0012)
Window: 11.250 msec (0x0012)
> HCI Event: Command Complete (0x0e) plen 4
LE Set Extended Scan Parameters (0x08|0x0041) ncmd 1
Status: Unknown HCI Command (0x01)

Signed-off-by: Sven Peter <sven@svenpeter.dev>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/bluetooth/hci.h | 10 ++++++++++
include/net/bluetooth/hci_core.h | 4 +++-
2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 4518c63e9d17..78c55b69919d 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -274,6 +274,16 @@ enum {
* during the hdev->setup vendor callback.
*/
HCI_QUIRK_BROKEN_ENHANCED_SETUP_SYNC_CONN,
+
+ /*
+ * When this quirk is set, the HCI_OP_LE_SET_EXT_SCAN_ENABLE command is
+ * disabled. This is required for some Broadcom controllers which
+ * erroneously claim to support extended scanning.
+ *
+ * This quirk can be set before hci_register_dev is called or
+ * during the hdev->setup vendor callback.
+ */
+ HCI_QUIRK_BROKEN_EXT_SCAN,
};

/* HCI device flags */
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index e7862903187d..29d1254f9856 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1681,7 +1681,9 @@ void hci_conn_del_sysfs(struct hci_conn *conn);

/* Use ext scanning if set ext scan param and ext scan enable is supported */
#define use_ext_scan(dev) (((dev)->commands[37] & 0x20) && \
- ((dev)->commands[37] & 0x40))
+ ((dev)->commands[37] & 0x40) && \
+ !test_bit(HCI_QUIRK_BROKEN_EXT_SCAN, &(dev)->quirks))
+
/* Use ext create connection if command is supported */
#define use_ext_conn(dev) ((dev)->commands[37] & 0x80)

--
2.35.1