Bluetooth: btintel: Add Intel devcoredump support

Intercept debug exception events from the controller and put them into
a devcoredump using hci devcoredump APIs. The debug exception contains
data in a TLV format and it will be parsed in userspace.

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Manish Mandlik <mmandlik@google.com>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Chethan Tumkur Narayan <chethan.tumkur.narayan@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

1 files changed, 47 insertions, 7 deletions

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 498e13102367..2303b0a66323 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2386,16 +2386,47 @@ static int btusb_recv_bulk_intel(struct btusb_data *data, void *buffer,
 	return btusb_recv_bulk(data, buffer, count);
 }
 
+static int btusb_intel_diagnostics(struct hci_dev *hdev, struct sk_buff *skb)
+{
+	struct intel_tlv *tlv = (void *)&skb->data[5];
+
+	/* The first event is always an event type TLV */
+	if (tlv->type != INTEL_TLV_TYPE_ID)
+		goto recv_frame;
+
+	switch (tlv->val[0]) {
+	case INTEL_TLV_SYSTEM_EXCEPTION:
+	case INTEL_TLV_FATAL_EXCEPTION:
+	case INTEL_TLV_DEBUG_EXCEPTION:
+	case INTEL_TLV_TEST_EXCEPTION:
+		/* Generate devcoredump from exception */
+		if (!hci_devcd_init(hdev, skb->len)) {
+			hci_devcd_append(hdev, skb);
+			hci_devcd_complete(hdev);
+		} else {
+			bt_dev_err(hdev, "Failed to generate devcoredump");
+			kfree_skb(skb);
+		}
+		return 0;
+	default:
+		bt_dev_err(hdev, "Invalid exception type %02X", tlv->val[0]);
+	}
+
+recv_frame:
+	return hci_recv_frame(hdev, skb);
+}
+
 static int btusb_recv_event_intel(struct hci_dev *hdev, struct sk_buff *skb)
 {
-	if (btintel_test_flag(hdev, INTEL_BOOTLOADER)) {
-		struct hci_event_hdr *hdr = (void *)skb->data;
+	struct hci_event_hdr *hdr = (void *)skb->data;
+	const char diagnostics_hdr[] = { 0x87, 0x80, 0x03 };
 
-		if (skb->len > HCI_EVENT_HDR_SIZE && hdr->evt == 0xff &&
-		    hdr->plen > 0) {
-			const void *ptr = skb->data + HCI_EVENT_HDR_SIZE + 1;
-			unsigned int len = skb->len - HCI_EVENT_HDR_SIZE - 1;
+	if (skb->len > HCI_EVENT_HDR_SIZE && hdr->evt == 0xff &&
+	    hdr->plen > 0) {
+		const void *ptr = skb->data + HCI_EVENT_HDR_SIZE + 1;
+		unsigned int len = skb->len - HCI_EVENT_HDR_SIZE - 1;
 
+		if (btintel_test_flag(hdev, INTEL_BOOTLOADER)) {
 			switch (skb->data[2]) {
 			case 0x02:
 				/* When switching to the operational firmware
@@ -2414,6 +2445,15 @@ static int btusb_recv_event_intel(struct hci_dev *hdev, struct sk_buff *skb)
 				break;
 			}
 		}
+
+		/* Handle all diagnostics events separately. May still call
+		 * hci_recv_frame.
+		 */
+		if (len >= sizeof(diagnostics_hdr) &&
+		    memcmp(&skb->data[2], diagnostics_hdr,
+			   sizeof(diagnostics_hdr)) == 0) {
+			return btusb_intel_diagnostics(hdev, skb);
+		}
 	}
 
 	return hci_recv_frame(hdev, skb);
@@ -4018,7 +4058,7 @@ static int btusb_probe(struct usb_interface *intf,
 
 	/* Combined Intel Device setup to support multiple setup routine */
 	if (id->driver_info & BTUSB_INTEL_COMBINED) {
-		err = btintel_configure_setup(hdev);
+		err = btintel_configure_setup(hdev, btusb_driver.name);
 		if (err)
 			goto out_free_dev;