[PATCH v2 2/2] Bluetooth: Support the vendor specific debug events

[PATCH v2 2/2] Bluetooth: Support the vendor specific debug events

[Joseph Hwang]

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 Tumkur Narayan <chethan.tumkur.narayan@intel.corp-partner.google.com>
Reviewed-by: Kiran Krishnappa <kiran.k@intel.corp-partner.google.com>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Signed-off-by: Joseph Hwang <josephsih@chromium.org>
---

(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@holtmann.org>");
 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

Re: [PATCH v2 2/2] Bluetooth: Support the vendor specific debug events

[Marcel Holtmann]

Hi Joseph,

> 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 Tumkur Narayan <chethan.tumkur.narayan@intel.corp-partner.google.com>
> Reviewed-by: Kiran Krishnappa <kiran.k@intel.corp-partner.google.com>
> Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
> Signed-off-by: Joseph Hwang <josephsih@chromium.org>
> ---
> 
> (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(-)

maybe I forgot to mention this, we don’t intermix core changes with driver changes to support it.

You first need to introduce the core feature and then patch the driver to support it.

Regards

Marcel