[PATCH v2 2/2] Bluetooth: btintel: surface Intel telemetry events through mgmt

From: Joseph Hwang
Date: Thu Jan 27 2022 - 05:18:18 EST


When receiving a HCI vendor event, the kernel checks if it is an
Intel telemetry event. If yes, the event is sent to bluez user
space through the mgmt socket.

Signed-off-by: Joseph Hwang <josephsih@xxxxxxxxxxxx>
Reviewed-by: Archie Pusaka <apusaka@xxxxxxxxxxxx>
---

Changes in v2:
- Drop the pull_quality_report_data function from hci_dev.
Do not bother hci_dev with it. Do not bleed the details
into the core.

drivers/bluetooth/btintel.c | 27 ++++++++++++++++++++++++++-
drivers/bluetooth/btintel.h | 7 +++++++
include/net/bluetooth/hci_core.h | 1 +
net/bluetooth/hci_event.c | 12 ++++++++++++
4 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/btintel.c b/drivers/bluetooth/btintel.c
index 1a4f8b227eac..9e1fdb68b669 100644
--- a/drivers/bluetooth/btintel.c
+++ b/drivers/bluetooth/btintel.c
@@ -2401,8 +2401,9 @@ static int btintel_setup_combined(struct hci_dev *hdev)
set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks);

- /* Set up the quality report callback for Intel devices */
+ /* Set up the quality report callbacks for Intel devices */
hdev->set_quality_report = btintel_set_quality_report;
+ hdev->is_quality_report_evt = btintel_is_quality_report_evt;

/* For Legacy device, check the HW platform value and size */
if (skb->len == sizeof(ver) && skb->data[1] == 0x37) {
@@ -2645,6 +2646,30 @@ void btintel_secure_send_result(struct hci_dev *hdev,
}
EXPORT_SYMBOL_GPL(btintel_secure_send_result);

+#define INTEL_PREFIX 0x8087
+#define TELEMETRY_CODE 0x03
+
+struct intel_prefix_evt_data {
+ __le16 vendor_prefix;
+ __u8 code;
+ __u8 data[]; /* a number of struct intel_tlv subevents */
+} __packed;
+
+bool btintel_is_quality_report_evt(struct sk_buff *skb)
+{
+ struct intel_prefix_evt_data *ev;
+ u16 vendor_prefix;
+
+ if (skb->len < sizeof(struct intel_prefix_evt_data))
+ return false;
+
+ ev = (struct intel_prefix_evt_data *)skb->data;
+ vendor_prefix = __le16_to_cpu(ev->vendor_prefix);
+
+ return vendor_prefix == INTEL_PREFIX && ev->code == TELEMETRY_CODE;
+}
+EXPORT_SYMBOL_GPL(btintel_is_quality_report_evt);
+
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 c9b24e9299e2..6dd4695b8b86 100644
--- a/drivers/bluetooth/btintel.h
+++ b/drivers/bluetooth/btintel.h
@@ -210,6 +210,7 @@ void btintel_bootup(struct hci_dev *hdev, const void *ptr, unsigned int len);
void btintel_secure_send_result(struct hci_dev *hdev,
const void *ptr, unsigned int len);
int btintel_set_quality_report(struct hci_dev *hdev, bool enable);
+bool btintel_is_quality_report_evt(struct sk_buff *skb);
#else

static inline int btintel_check_bdaddr(struct hci_dev *hdev)
@@ -305,4 +306,10 @@ static inline int btintel_set_quality_report(struct hci_dev *hdev, bool enable)
{
return -ENODEV;
}
+
+static inline bool btintel_is_quality_report_evt(struct sk_buff *skb)
+{
+ return false;
+}
+
#endif
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index b726fd595895..9d855ac1cb29 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -632,6 +632,7 @@ struct hci_dev {
void (*cmd_timeout)(struct hci_dev *hdev);
bool (*wakeup)(struct hci_dev *hdev);
int (*set_quality_report)(struct hci_dev *hdev, bool enable);
+ bool (*is_quality_report_evt)(struct sk_buff *skb);
int (*get_data_path_id)(struct hci_dev *hdev, __u8 *data_path);
int (*get_codec_config_data)(struct hci_dev *hdev, __u8 type,
struct bt_codec *codec, __u8 *vnd_len,
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 1b69d3efd415..892a48d2f6be 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4238,6 +4238,16 @@ static void aosp_quality_report_evt(struct hci_dev *hdev, void *data,
QUALITY_SPEC_AOSP_BQR);
}

+static void intel_vendor_evt(struct hci_dev *hdev, void *data,
+ struct sk_buff *skb)
+{
+ /* Only interested in the telemetry event for now. */
+ if (hdev->set_quality_report &&
+ hdev->is_quality_report_evt && hdev->is_quality_report_evt(skb))
+ mgmt_quality_report(hdev, skb->data, skb->len,
+ QUALITY_SPEC_INTEL_TELEMETRY);
+}
+
/* Define the fixed vendor event prefixes below.
* Note: AOSP HCI Requirements use 0x54 and up as sub-event codes without
* actually defining a vendor prefix. Refer to
@@ -4246,6 +4256,7 @@ static void aosp_quality_report_evt(struct hci_dev *hdev, void *data,
* space to avoid collision.
*/
static unsigned char AOSP_BQR_PREFIX[] = { 0x58 };
+static unsigned char INTEL_PREFIX[] = { 0x87, 0x80 };

/* Some vendor prefixes are fixed values and lengths. */
#define FIXED_EVT_PREFIX(_prefix, _vendor_func) \
@@ -4283,6 +4294,7 @@ struct vendor_event_prefix {
__u8 (*get_prefix_len)(struct hci_dev *hdev);
} evt_prefixes[] = {
FIXED_EVT_PREFIX(AOSP_BQR_PREFIX, aosp_quality_report_evt),
+ FIXED_EVT_PREFIX(INTEL_PREFIX, intel_vendor_evt),
DYNAMIC_EVT_PREFIX(get_msft_evt_prefix, get_msft_evt_prefix_len,
msft_vendor_evt),

--
2.35.0.rc0.227.g00780c9af4-goog