2 files changed, 134 insertions, 0 deletions

diff --git a/drivers/bluetooth/btrtl.c b/drivers/bluetooth/btrtl.c
index 0500b598691e..75d6acb3ee82 100644
--- a/drivers/bluetooth/btrtl.c
+++ b/drivers/bluetooth/btrtl.c
@@ -34,6 +34,7 @@
 #define RTL_ROM_LMP_8821A	0x8821
 #define RTL_ROM_LMP_8761A	0x8761
 #define RTL_ROM_LMP_8822B	0x8822
+#define RTL_CONFIG_MAGIC	0x8723ab55
 
 #define IC_MATCH_FL_LMPSUBV	(1 << 0)
 #define IC_MATCH_FL_HCIREV	(1 << 1)
@@ -587,6 +588,114 @@ int btrtl_setup_realtek(struct hci_dev *hdev)
 }
 EXPORT_SYMBOL_GPL(btrtl_setup_realtek);
 
+static unsigned int btrtl_convert_baudrate(u32 device_baudrate)
+{
+	switch (device_baudrate) {
+	case 0x0252a00a:
+		return 230400;
+
+	case 0x05f75004:
+		return 921600;
+
+	case 0x00005004:
+		return 1000000;
+
+	case 0x04928002:
+	case 0x01128002:
+		return 1500000;
+
+	case 0x00005002:
+		return 2000000;
+
+	case 0x0000b001:
+		return 2500000;
+
+	case 0x04928001:
+		return 3000000;
+
+	case 0x052a6001:
+		return 3500000;
+
+	case 0x00005001:
+		return 4000000;
+
+	case 0x0252c014:
+	default:
+		return 115200;
+	}
+}
+
+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)
+{
+	struct rtl_vendor_config *config;
+	struct rtl_vendor_config_entry *entry;
+	int i, total_data_len;
+	bool found = false;
+
+	total_data_len = btrtl_dev->cfg_len - sizeof(*config);
+	if (total_data_len <= 0) {
+		rtl_dev_warn(hdev, "no config loaded\n");
+		return -EINVAL;
+	}
+
+	config = (struct rtl_vendor_config *)btrtl_dev->cfg_data;
+	if (le32_to_cpu(config->signature) != RTL_CONFIG_MAGIC) {
+		rtl_dev_err(hdev, "invalid config magic\n");
+		return -EINVAL;
+	}
+
+	if (total_data_len < le16_to_cpu(config->total_len)) {
+		rtl_dev_err(hdev, "config is too short\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < total_data_len; ) {
+		entry = ((void *)config->entry) + i;
+
+		switch (le16_to_cpu(entry->offset)) {
+		case 0xc:
+			if (entry->len < sizeof(*device_baudrate)) {
+				rtl_dev_err(hdev, "invalid UART config entry\n");
+				return -EINVAL;
+			}
+
+			*device_baudrate = get_unaligned_le32(entry->data);
+			*controller_baudrate = btrtl_convert_baudrate(
+							*device_baudrate);
+
+			if (entry->len >= 13)
+				*flow_control = !!(entry->data[12] & BIT(2));
+			else
+				*flow_control = false;
+
+			found = true;
+			break;
+
+		default:
+			rtl_dev_dbg(hdev, "skipping config entry 0x%x (len %u)\n",
+				   le16_to_cpu(entry->offset), entry->len);
+			break;
+		};
+
+		i += sizeof(*entry) + entry->len;
+	}
+
+	if (!found) {
+		rtl_dev_err(hdev, "no UART config entry found\n");
+		return -ENOENT;
+	}
+
+	rtl_dev_dbg(hdev, "device baudrate = 0x%08x\n", *device_baudrate);
+	rtl_dev_dbg(hdev, "controller baudrate = %u\n", *controller_baudrate);
+	rtl_dev_dbg(hdev, "flow control %d\n", *flow_control);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(btrtl_get_uart_settings);
+
 MODULE_AUTHOR("Daniel Drake <drake@endlessm.com>");
 MODULE_DESCRIPTION("Bluetooth support for Realtek devices ver " VERSION);
 MODULE_VERSION(VERSION);
diff --git a/drivers/bluetooth/btrtl.h b/drivers/bluetooth/btrtl.h
index e41974f8af40..9249ad1e9a1d 100644
--- a/drivers/bluetooth/btrtl.h
+++ b/drivers/bluetooth/btrtl.h
@@ -45,6 +45,18 @@ struct rtl_epatch_header {
 	__le16 num_patches;
 } __packed;
 
+struct rtl_vendor_config_entry {
+	__le16 offset;
+	__u8 len;
+	__u8 data[0];
+} __packed;
+
+struct rtl_vendor_config {
+	__le32 signature;
+	__le16 total_len;
+	struct rtl_vendor_config_entry entry[0];
+} __packed;
+
 #if IS_ENABLED(CONFIG_BT_RTL)
 
 struct btrtl_device_info *btrtl_initialize(struct hci_dev *hdev);
@@ -52,6 +64,10 @@ void btrtl_free(struct btrtl_device_info *btrtl_dev);
 int btrtl_download_firmware(struct hci_dev *hdev,
 			    struct btrtl_device_info *btrtl_dev);
 int btrtl_setup_realtek(struct hci_dev *hdev);
+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);
 
 #else
 
@@ -75,4 +91,13 @@ static inline int btrtl_setup_realtek(struct hci_dev *hdev)
 	return -EOPNOTSUPP;
 }
 
+static inline 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)
+{
+	return -ENOENT;
+}
+
 #endif