[PATCH v3 2/2] Bluetooth: Support the vendor specific debug events

From: Joseph Hwang
Date: Tue Apr 13 2021 - 06:18:27 EST


This patch allows a user space process to enable/disable the vendor
specific (vs) debug events dynamically through the set experimental
feature mgmt interface if CONFIG_BT_FEATURE_VS_DBG_EVT is enabled.

Since the debug event feature needs to invoke the callback function
provided by the driver, i.e., hdev->set_vs_dbg_evt, a valid controller
index is required.

For generic Linux machines, the vendor specific debug events are
disabled by default.

Reviewed-by: Chethan T N <chethan.tumkur.narayan@xxxxxxxxx>
Reviewed-by: Kiran Krishnappa <kiran.k@xxxxxxxxx>
Reviewed-by: Miao-chen Chou <mcchou@xxxxxxxxxxxx>
Signed-off-by: Joseph Hwang <josephsih@xxxxxxxxxxxx>
---

(no changes since v1)

drivers/bluetooth/btintel.c | 73 ++++++++++++++++++++-
drivers/bluetooth/btintel.h | 13 ++++
drivers/bluetooth/btusb.c | 16 +++++
include/net/bluetooth/hci.h | 4 ++
include/net/bluetooth/hci_core.h | 10 +++
net/bluetooth/Kconfig | 10 +++
net/bluetooth/mgmt.c | 108 ++++++++++++++++++++++++++++++-
7 files changed, 232 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/btintel.c b/drivers/bluetooth/btintel.c
index de1dbdc01e5a..c0f81d29aa5f 100644
--- a/drivers/bluetooth/btintel.c
+++ b/drivers/bluetooth/btintel.c
@@ -1213,6 +1213,7 @@ void btintel_reset_to_bootloader(struct hci_dev *hdev)
}
EXPORT_SYMBOL_GPL(btintel_reset_to_bootloader);

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
int btintel_read_debug_features(struct hci_dev *hdev,
struct intel_debug_features *features)
{
@@ -1254,14 +1255,18 @@ int btintel_set_debug_features(struct hci_dev *hdev,
u8 trace_enable = 0x02;
struct sk_buff *skb;

- if (!features)
+ if (!features) {
+ bt_dev_warn(hdev, "Debug features not read");
return -EINVAL;
+ }

if (!(features->page1[0] & 0x3f)) {
bt_dev_info(hdev, "Telemetry exception format not supported");
return 0;
}

+ bt_dev_info(hdev, "trace_enable %d mask %d", trace_enable, mask[3]);
+
skb = __hci_cmd_sync(hdev, 0xfc8b, 11, mask, HCI_INIT_TIMEOUT);
if (IS_ERR(skb)) {
bt_dev_err(hdev, "Setting Intel telemetry ddc write event mask failed (%ld)",
@@ -1290,6 +1295,72 @@ int btintel_set_debug_features(struct hci_dev *hdev,
}
EXPORT_SYMBOL_GPL(btintel_set_debug_features);

+int btintel_reset_debug_features(struct hci_dev *hdev,
+ const struct intel_debug_features *features)
+{
+ u8 mask[11] = { 0x0a, 0x92, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00 };
+ u8 trace_enable = 0x00;
+ struct sk_buff *skb;
+
+ if (!features) {
+ bt_dev_warn(hdev, "Debug features not read");
+ return -EINVAL;
+ }
+
+ if (!(features->page1[0] & 0x3f)) {
+ bt_dev_info(hdev, "Telemetry exception format not supported");
+ return 0;
+ }
+
+ bt_dev_info(hdev, "trace_enable %d mask %d", trace_enable, mask[3]);
+
+ /* Should stop the trace before writing ddc event mask. */
+ skb = __hci_cmd_sync(hdev, 0xfca1, 1, &trace_enable, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb)) {
+ bt_dev_err(hdev, "Stop tracing of link statistics events failed (%ld)",
+ PTR_ERR(skb));
+ return PTR_ERR(skb);
+ }
+ kfree_skb(skb);
+
+ skb = __hci_cmd_sync(hdev, 0xfc8b, 11, mask, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb)) {
+ bt_dev_err(hdev, "Setting Intel telemetry ddc write event mask failed (%ld)",
+ PTR_ERR(skb));
+ return PTR_ERR(skb);
+ }
+ kfree_skb(skb);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(btintel_reset_debug_features);
+
+int btintel_set_vs_dbg_evt(struct hci_dev *hdev, bool enable)
+{
+ struct intel_debug_features features;
+ int err;
+
+ bt_dev_dbg(hdev, "enable %d", enable);
+
+ /* Read the Intel supported features and if new exception formats
+ * supported, need to load the additional DDC config to enable.
+ */
+ err = btintel_read_debug_features(hdev, &features);
+ if (err)
+ return err;
+
+ /* Set or reset the debug features. */
+ if (enable)
+ err = btintel_set_debug_features(hdev, &features);
+ else
+ err = btintel_reset_debug_features(hdev, &features);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(btintel_set_vs_dbg_evt);
+#endif
+
MODULE_AUTHOR("Marcel Holtmann <marcel@xxxxxxxxxxxx>");
MODULE_DESCRIPTION("Bluetooth support for Intel devices ver " VERSION);
MODULE_VERSION(VERSION);
diff --git a/drivers/bluetooth/btintel.h b/drivers/bluetooth/btintel.h
index d184064a5e7c..0b35b0248b91 100644
--- a/drivers/bluetooth/btintel.h
+++ b/drivers/bluetooth/btintel.h
@@ -171,10 +171,15 @@ int btintel_download_firmware_newgen(struct hci_dev *hdev,
u32 *boot_param, u8 hw_variant,
u8 sbe_type);
void btintel_reset_to_bootloader(struct hci_dev *hdev);
+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
int btintel_read_debug_features(struct hci_dev *hdev,
struct intel_debug_features *features);
int btintel_set_debug_features(struct hci_dev *hdev,
const struct intel_debug_features *features);
+int btintel_reset_debug_features(struct hci_dev *hdev,
+ const struct intel_debug_features *features);
+int btintel_set_vs_dbg_evt(struct hci_dev *hdev, bool enable);
+#endif
#else

static inline int btintel_check_bdaddr(struct hci_dev *hdev)
@@ -301,10 +306,18 @@ static inline int btintel_read_debug_features(struct hci_dev *hdev,
return -EOPNOTSUPP;
}

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
static inline int btintel_set_debug_features(struct hci_dev *hdev,
const struct intel_debug_features *features)
{
return -EOPNOTSUPP;
}

+static inline int btintel_reset_debug_features(struct hci_dev *hdev,
+ const struct intel_debug_features *features)
+{
+ return -EOPNOTSUPP;
+}
+#endif
+
#endif
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index f29946f15f59..55e73d4f419f 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2864,6 +2864,11 @@ static int btusb_setup_intel_new(struct hci_dev *hdev)
btintel_load_ddc_config(hdev, ddcname);
}

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ hci_dev_clear_flag(hdev, HCI_VS_DBG_EVT);
+ bt_dev_dbg(hdev, "HCI_VS_DBG_EVT cleared");
+#endif
+
/* Read the Intel version information after loading the FW */
err = btintel_read_version(hdev, &ver);
if (err)
@@ -2951,6 +2956,11 @@ static int btusb_setup_intel_newgen(struct hci_dev *hdev)
*/
btintel_load_ddc_config(hdev, ddcname);

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ hci_dev_clear_flag(hdev, HCI_VS_DBG_EVT);
+ bt_dev_dbg(hdev, "HCI_VS_DBG_EVT cleared");
+#endif
+
/* Read the Intel version information after loading the FW */
err = btintel_read_version_tlv(hdev, &version);
if (err)
@@ -4587,6 +4597,9 @@ static int btusb_probe(struct usb_interface *intf,
hdev->set_diag = btintel_set_diag;
hdev->set_bdaddr = btintel_set_bdaddr;
hdev->cmd_timeout = btusb_intel_cmd_timeout;
+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ hdev->set_vs_dbg_evt = btintel_set_vs_dbg_evt;
+#endif
set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks);
@@ -4601,6 +4614,9 @@ static int btusb_probe(struct usb_interface *intf,
hdev->set_diag = btintel_set_diag;
hdev->set_bdaddr = btintel_set_bdaddr;
hdev->cmd_timeout = btusb_intel_cmd_timeout;
+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ hdev->set_vs_dbg_evt = btintel_set_vs_dbg_evt;
+#endif
set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks);
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index ea4ae551c426..0c1eba73844a 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -331,6 +331,10 @@ enum {
HCI_CMD_PENDING,
HCI_FORCE_NO_MITM,

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ HCI_VS_DBG_EVT,
+#endif
+
__HCI_NUM_FLAGS,
};

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index c73ac52af186..d68e06be51c7 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -604,6 +604,9 @@ struct hci_dev {
int (*set_bdaddr)(struct hci_dev *hdev, const bdaddr_t *bdaddr);
void (*cmd_timeout)(struct hci_dev *hdev);
bool (*prevent_wake)(struct hci_dev *hdev);
+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ int (*set_vs_dbg_evt)(struct hci_dev *hdev, bool enable);
+#endif
};

#define HCI_PHY_HANDLE(handle) (handle & 0xff)
@@ -751,12 +754,19 @@ extern struct mutex hci_cb_list_lock;
#define hci_dev_test_and_clear_flag(hdev, nr) test_and_clear_bit((nr), (hdev)->dev_flags)
#define hci_dev_test_and_change_flag(hdev, nr) test_and_change_bit((nr), (hdev)->dev_flags)

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+#define hci_dev_clear_flag_vs_dbg_evt(x) { hci_dev_clear_flag(hdev, x); }
+#else
+#define hci_dev_clear_flag_vs_dbg_evt(x) {}
+#endif
+
#define hci_dev_clear_volatile_flags(hdev) \
do { \
hci_dev_clear_flag(hdev, HCI_LE_SCAN); \
hci_dev_clear_flag(hdev, HCI_LE_ADV); \
hci_dev_clear_flag(hdev, HCI_LL_RPA_RESOLUTION);\
hci_dev_clear_flag(hdev, HCI_PERIODIC_INQ); \
+ hci_dev_clear_flag_vs_dbg_evt(HCI_VS_DBG_EVT) \
} while (0)

/* ----- HCI interface to upper protocols ----- */
diff --git a/net/bluetooth/Kconfig b/net/bluetooth/Kconfig
index e0ab4cd7afc3..4930ec495f60 100644
--- a/net/bluetooth/Kconfig
+++ b/net/bluetooth/Kconfig
@@ -148,4 +148,14 @@ config BT_FEATURE_DEBUG
This provides an option to enable/disable debugging statements
at runtime via the experimental features interface.

+config BT_FEATURE_VS_DBG_EVT
+ bool "Enable runtime option for logging vendor specific debug events"
+ depends on BT && !DYNAMIC_DEBUG
+ default n
+ help
+ This provides an option to enable/disable vendor specific debug
+ events logging at runtime via the experimental features interface.
+ The debug events may include the categories of system exceptions,
+ connections/disconnection, the link quality statistics, etc.
+
source "drivers/bluetooth/Kconfig"
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index f9be7f9084d6..a4344b78a6a0 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -3788,6 +3788,14 @@ static const u8 debug_uuid[16] = {
};
#endif

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+/* 330859bc-7506-492d-9370-9a6f0614037f */
+static const u8 vs_dbg_evt_uuid[16] = {
+ 0x7f, 0x03, 0x14, 0x06, 0x6f, 0x9a, 0x70, 0x93,
+ 0x2d, 0x49, 0x06, 0x75, 0xbc, 0x59, 0x08, 0x33,
+};
+#endif
+
/* 671b10b5-42c0-4696-9227-eb28d1b049d6 */
static const u8 simult_central_periph_uuid[16] = {
0xd6, 0x49, 0xb0, 0xd1, 0x28, 0xeb, 0x27, 0x92,
@@ -3803,7 +3811,7 @@ static const u8 rpa_resolution_uuid[16] = {
static int read_exp_features_info(struct sock *sk, struct hci_dev *hdev,
void *data, u16 data_len)
{
- char buf[62]; /* Enough space for 3 features */
+ char buf[82]; /* Enough space for 4 features: 2 + 20 * 4 */
struct mgmt_rp_read_exp_features_info *rp = (void *)buf;
u16 idx = 0;
u32 flags;
@@ -3847,6 +3855,15 @@ static int read_exp_features_info(struct sock *sk, struct hci_dev *hdev,
idx++;
}

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ if (hdev) {
+ flags = hci_dev_test_flag(hdev, HCI_VS_DBG_EVT) ? BIT(0) : 0;
+ memcpy(rp->features[idx].uuid, vs_dbg_evt_uuid, 16);
+ rp->features[idx].flags = cpu_to_le32(flags);
+ idx++;
+ }
+#endif
+
rp->feature_count = cpu_to_le16(idx);

/* After reading the experimental features information, enable
@@ -3889,6 +3906,23 @@ static int exp_debug_feature_changed(bool enabled, struct sock *skip)
}
#endif

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+static int exp_vs_dbg_evt_feature_changed(bool enabled, struct sock *skip)
+{
+ struct mgmt_ev_exp_feature_changed ev;
+
+ BT_INFO("enabled %d", enabled);
+
+ memset(&ev, 0, sizeof(ev));
+ memcpy(ev.uuid, vs_dbg_evt_uuid, 16);
+ ev.flags = cpu_to_le32(enabled ? BIT(0) : 0);
+
+ return mgmt_limited_event(MGMT_EV_EXP_FEATURE_CHANGED, NULL,
+ &ev, sizeof(ev),
+ HCI_MGMT_EXP_FEATURE_EVENTS, skip);
+}
+#endif
+
static int set_exp_feature(struct sock *sk, struct hci_dev *hdev,
void *data, u16 data_len)
{
@@ -4035,6 +4069,78 @@ static int set_exp_feature(struct sock *sk, struct hci_dev *hdev,
return err;
}

+#ifdef CONFIG_BT_FEATURE_VS_DBG_EVT
+ if (!memcmp(cp->uuid, vs_dbg_evt_uuid, 16)) {
+ bool val, changed;
+ int err;
+ u16 mgmt_index = hdev ? hdev->id : MGMT_INDEX_NONE;
+
+ /* Command requires to use a valid controller index */
+ if (!hdev)
+ return mgmt_cmd_status(sk, hdev->id,
+ MGMT_OP_SET_EXP_FEATURE,
+ MGMT_STATUS_INVALID_INDEX);
+
+ /* Parameters are limited to a single octet */
+ if (data_len != MGMT_SET_EXP_FEATURE_SIZE + 1)
+ return mgmt_cmd_status(sk, mgmt_index,
+ MGMT_OP_SET_EXP_FEATURE,
+ MGMT_STATUS_INVALID_PARAMS);
+
+ /* Only boolean on/off is supported */
+ if (cp->param[0] != 0x00 && cp->param[0] != 0x01)
+ return mgmt_cmd_status(sk, mgmt_index,
+ MGMT_OP_SET_EXP_FEATURE,
+ MGMT_STATUS_INVALID_PARAMS);
+
+ hci_req_sync_lock(hdev);
+
+ val = !!cp->param[0];
+ changed = (val != hci_dev_test_flag(hdev, HCI_VS_DBG_EVT));
+
+ if (!hdev->set_vs_dbg_evt) {
+ BT_INFO("vendor specific debug event not supported");
+ err = mgmt_cmd_status(sk, mgmt_index,
+ MGMT_OP_SET_EXP_FEATURE,
+ MGMT_STATUS_NOT_SUPPORTED);
+ goto unlock_vs_dbg_evt;
+ }
+
+ if (changed) {
+ err = hdev->set_vs_dbg_evt(hdev, val);
+ if (err) {
+ BT_ERR("set_vs_dbg_evt value %d err %d",
+ val, err);
+ err = mgmt_cmd_status(sk, mgmt_index,
+ MGMT_OP_SET_EXP_FEATURE,
+ MGMT_STATUS_FAILED);
+ goto unlock_vs_dbg_evt;
+ }
+ if (val)
+ hci_dev_set_flag(hdev, HCI_VS_DBG_EVT);
+ else
+ hci_dev_clear_flag(hdev, HCI_VS_DBG_EVT);
+ }
+
+ BT_INFO("vendor specific debug event %d changed %d",
+ val, changed);
+
+ memcpy(rp.uuid, vs_dbg_evt_uuid, 16);
+ rp.flags = cpu_to_le32(val ? BIT(0) : 0);
+ hci_sock_set_flag(sk, HCI_MGMT_EXP_FEATURE_EVENTS);
+ err = mgmt_cmd_complete(sk, mgmt_index,
+ MGMT_OP_SET_EXP_FEATURE, 0,
+ &rp, sizeof(rp));
+
+ if (changed)
+ exp_vs_dbg_evt_feature_changed(val, sk);
+
+unlock_vs_dbg_evt:
+ hci_req_sync_unlock(hdev);
+ return err;
+ }
+#endif
+
return mgmt_cmd_status(sk, hdev ? hdev->id : MGMT_INDEX_NONE,
MGMT_OP_SET_EXP_FEATURE,
MGMT_STATUS_NOT_SUPPORTED);
--
2.31.1.295.g9ea45b61b8-goog