Bluetooth: btrtl: Add Realtek devcoredump support

Catch debug exception from controller and driver, and trigger a
devcoredump using hci devcoredump APIs. The debug exception data
will be parsed in userspace.
Signed-off-by: Alex Lu <alex_lu@realsil.com.cn>
Signed-off-by: Hilda Wu <hildawu@realtek.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

drivers/bluetooth/btrtl.h

@@ -109,8 +109,16 @@ enum {
 	__REALTEK_NUM_FLAGS,
 };
 
+struct rtl_dump_info {
+	const char *driver_name;
+	char *controller;
+	u32  fw_version;
+};
+
 struct btrealtek_data {
 	DECLARE_BITMAP(flags, __REALTEK_NUM_FLAGS);
+
+	struct rtl_dump_info rtl_dump;
 };
 
 #define btrealtek_set_flag(hdev, nr)					\
@@ -139,6 +147,7 @@ int btrtl_get_uart_settings(struct hci_dev *hdev,
 			    struct btrtl_device_info *btrtl_dev,
 			    unsigned int *controller_baudrate,
 			    u32 *device_baudrate, bool *flow_control);
+void btrtl_set_driver_name(struct hci_dev *hdev, const char *driver_name);
 
 #else
 
@@ -182,4 +191,8 @@ static inline int btrtl_get_uart_settings(struct hci_dev *hdev,
 	return -ENOENT;
 }
 
+static inline void btrtl_set_driver_name(struct hci_dev *hdev, const char *driver_name)
+{
+}
+
 #endif

drivers/bluetooth/btusb.c

@@ -887,10 +887,49 @@ static void btusb_intel_cmd_timeout(struct hci_dev *hdev)
 	gpiod_set_value_cansleep(reset_gpio, 0);
 }
 
+#define RTK_DEVCOREDUMP_CODE_MEMDUMP		0x01
+#define RTK_DEVCOREDUMP_CODE_HW_ERR		0x02
+#define RTK_DEVCOREDUMP_CODE_CMD_TIMEOUT	0x03
+
+#define RTK_SUB_EVENT_CODE_COREDUMP		0x34
+
+struct rtk_dev_coredump_hdr {
+	u8 type;
+	u8 code;
+	u8 reserved[2];
+} __packed;
+
+static inline void btusb_rtl_alloc_devcoredump(struct hci_dev *hdev,
+		struct rtk_dev_coredump_hdr *hdr, u8 *buf, u32 len)
+{
+	struct sk_buff *skb;
+
+	skb = alloc_skb(len + sizeof(*hdr), GFP_ATOMIC);
+	if (!skb)
+		return;
+
+	skb_put_data(skb, hdr, sizeof(*hdr));
+	if (len)
+		skb_put_data(skb, buf, len);
+
+	if (!hci_devcd_init(hdev, skb->len)) {
+		hci_devcd_append(hdev, skb);
+		hci_devcd_complete(hdev);
+	} else {
+		bt_dev_err(hdev, "RTL: Failed to generate devcoredump");
+		kfree_skb(skb);
+	}
+}
+
 static void btusb_rtl_cmd_timeout(struct hci_dev *hdev)
 {
 	struct btusb_data *data = hci_get_drvdata(hdev);
 	struct gpio_desc *reset_gpio = data->reset_gpio;
+	struct rtk_dev_coredump_hdr hdr = {
+		.type = RTK_DEVCOREDUMP_CODE_CMD_TIMEOUT,
+	};
+
+	btusb_rtl_alloc_devcoredump(hdev, &hdr, NULL, 0);
 
 	if (++data->cmd_timeout_cnt < 5)
 		return;
@@ -917,6 +956,18 @@ static void btusb_rtl_cmd_timeout(struct hci_dev *hdev)
 	gpiod_set_value_cansleep(reset_gpio, 0);
 }
 
+static void btusb_rtl_hw_error(struct hci_dev *hdev, u8 code)
+{
+	struct rtk_dev_coredump_hdr hdr = {
+		.type = RTK_DEVCOREDUMP_CODE_HW_ERR,
+		.code = code,
+	};
+
+	bt_dev_err(hdev, "RTL: hw err, trigger devcoredump (%d)", code);
+
+	btusb_rtl_alloc_devcoredump(hdev, &hdr, NULL, 0);
+}
+
 static void btusb_qca_cmd_timeout(struct hci_dev *hdev)
 {
 	struct btusb_data *data = hci_get_drvdata(hdev);
@@ -2562,6 +2613,25 @@ static int btusb_setup_realtek(struct hci_dev *hdev)
 	return ret;
 }
 
+static int btusb_recv_event_realtek(struct hci_dev *hdev, struct sk_buff *skb)
+{
+	if (skb->data[0] == HCI_VENDOR_PKT && skb->data[2] == RTK_SUB_EVENT_CODE_COREDUMP) {
+		struct rtk_dev_coredump_hdr hdr = {
+			.code = RTK_DEVCOREDUMP_CODE_MEMDUMP,
+		};
+
+		bt_dev_dbg(hdev, "RTL: received coredump vendor evt, len %u",
+			skb->len);
+
+		btusb_rtl_alloc_devcoredump(hdev, &hdr, skb->data, skb->len);
+		kfree_skb(skb);
+
+		return 0;
+	}
+
+	return hci_recv_frame(hdev, skb);
+}
+
 /* UHW CR mapping */
 #define MTK_BT_MISC		0x70002510
 #define MTK_BT_SUBSYS_RST	0x70002610
@@ -4201,6 +4271,8 @@ static int btusb_probe(struct usb_interface *intf,
 	} else if (id->driver_info & BTUSB_REALTEK) {
 		/* Allocate extra space for Realtek device */
 		priv_size += sizeof(struct btrealtek_data);
+
+		data->recv_event = btusb_recv_event_realtek;
 	}
 
 	data->recv_acl = hci_recv_frame;
@@ -4364,9 +4436,11 @@ static int btusb_probe(struct usb_interface *intf,
 
 	if (IS_ENABLED(CONFIG_BT_HCIBTUSB_RTL) &&
 	    (id->driver_info & BTUSB_REALTEK)) {
+		btrtl_set_driver_name(hdev, btusb_driver.name);
 		hdev->setup = btusb_setup_realtek;
 		hdev->shutdown = btrtl_shutdown_realtek;
 		hdev->cmd_timeout = btusb_rtl_cmd_timeout;
+		hdev->hw_error = btusb_rtl_hw_error;
 
 		/* Realtek devices need to set remote wakeup on auto-suspend */
 		set_bit(BTUSB_WAKEUP_AUTOSUSPEND, &data->flags);