Driver: hci_nxp_setup: Support HCI baudrate update

Change running baudrate from `115200` from `3000000`.

Implement the function `bt_h4_vnd_setup` to update the HCI bandrate.

Add Kconfig `BT_H4_NXP_CTLR_WAIT_TIME_AFTER_BAUDRATE_UPDATE` to set
the waiting time after the controller bandrate HCI vendor specific
command sent. It is used to ensure the controller is ready to update
HCI bandrate.

Select `BT_HCI_SETUP` if `BT_H4_NXP_CTLR` is enabled.

Signed-off-by: Lyle Zhu <[email protected]>

Author: lylezhu2012

boards/nxp/mimxrt1170_evk/mimxrt1170_evk_mimxrt1176_cm7_B.overlay

@@ -89,7 +89,7 @@ m2_hci_uart: &lpuart2 {
 			compatible = "nxp,bt-hci-uart";
 			sdio-reset-gpios = <&gpio9 15 GPIO_ACTIVE_HIGH>;
 			w-disable-gpios = <&gpio9 30 GPIO_ACTIVE_HIGH>;
-			hci-operation-speed = <115200>;
+			hci-operation-speed = <3000000>;
 			hw-flow-control;
 			fw-download-primary-speed = <115200>;
 			fw-download-secondary-speed = <3000000>;

drivers/bluetooth/hci/Kconfig

@@ -304,6 +304,7 @@ config BT_H4_NXP_CTLR
 	select GPIO
 	depends on BT_H4
 	select CRC
+	select BT_HCI_SETUP
 	default y
 	depends on DT_HAS_NXP_BT_HCI_UART_ENABLED
 	help
@@ -327,4 +328,11 @@ config BT_H4_NXP_CTLR_WAIT_TIME_AFTER_UPLOAD
 	help
 	  Waiting time after firmware is uploaded. Unit is millisecond.
 
+config BT_H4_NXP_CTLR_WAIT_TIME_AFTER_BAUDRATE_UPDATE
+	int "Waiting time after controller baudrate is updated"
+	range 500 5000
+	default 500
+	help
+	  Waiting time after controller baudrate is updated. Unit is millisecond.
+
 endif #BT_H4_NXP_CTLR

drivers/bluetooth/hci/hci_nxp_setup.c

@@ -6,6 +6,7 @@
 
 #include <errno.h>
 #include <stddef.h>
+#include <string.h>
 
 #include <zephyr/kernel.h>
 #include <zephyr/arch/cpu.h>
@@ -16,7 +17,9 @@
 #include <zephyr/sys/util.h>
 #include <zephyr/sys/byteorder.h>
 #include <zephyr/sys/crc.h>
-#include <string.h>
+
+#include <zephyr/bluetooth/bluetooth.h>
+#include <zephyr/bluetooth/hci.h>
 
 #define LOG_LEVEL CONFIG_BT_HCI_DRIVER_LOG_LEVEL
 #include <zephyr/logging/log.h>
@@ -1056,7 +1059,6 @@ static int bt_nxp_ctlr_init(void)
 	}
 
 	speed = DT_PROP(DT_INST_GPARENT(0), current_speed);
-	speed = DT_PROP_OR(DT_DRV_INST(0), hci_operation_speed, speed);
 	uart_dev_data.primary_speed = DT_PROP_OR(DT_DRV_INST(0), fw_download_primary_speed, speed);
 	uart_dev_data.secondary_speed =
 		DT_PROP_OR(DT_DRV_INST(0), fw_download_secondary_speed, speed);
@@ -1175,3 +1177,70 @@ int bt_hci_transport_setup(const struct device *dev)
 
 	return bt_nxp_ctlr_init();
 }
+
+#define BT_HCI_VSC_BAUDRATE_UPDATE_LENGTH 4
+#define BT_HCI_VSC_BAUDRATE_UPDATE_OPCODE BT_OP(BT_OGF_VS, 0x09)
+
+static int bt_hci_baudrate_update(const struct device *dev, uint32_t baudrate)
+{
+	int err;
+	struct net_buf *buf;
+
+	buf = bt_hci_cmd_create(BT_HCI_VSC_BAUDRATE_UPDATE_OPCODE,
+				BT_HCI_VSC_BAUDRATE_UPDATE_LENGTH);
+	if (!buf) {
+		LOG_ERR("Fail to allocate buffer");
+		return -ENOBUFS;
+	}
+
+	/* Add new baudrate to the buffer */
+	net_buf_add_le32(buf, baudrate);
+
+	err = bt_hci_cmd_send_sync(BT_HCI_VSC_BAUDRATE_UPDATE_OPCODE, buf, NULL);
+	if (err) {
+		LOG_ERR("Fail to send baudrate update cmd");
+		return err;
+	}
+
+	return 0;
+}
+
+int bt_h4_vnd_setup(const struct device *dev)
+{
+	int err;
+	uint32_t default_speed;
+	uint32_t operation_speed;
+	bool flowcontrol_of_hci;
+
+	if (dev != uart_dev) {
+		return -EINVAL;
+	}
+
+	if (!device_is_ready(uart_dev)) {
+		return -ENODEV;
+	}
+
+	default_speed = DT_PROP(DT_INST_GPARENT(0), current_speed);
+	operation_speed = DT_PROP_OR(DT_DRV_INST(0), hci_operation_speed, default_speed);
+	flowcontrol_of_hci = (bool)DT_PROP_OR(DT_DRV_INST(0), hw_flow_control, false);
+
+	if (operation_speed == default_speed) {
+		return 0;
+	}
+
+	err = bt_hci_baudrate_update(dev, operation_speed);
+	if (err) {
+		return err;
+	}
+
+	/* BT waiting time after controller bandrate updated */
+	(void)k_msleep(CONFIG_BT_H4_NXP_CTLR_WAIT_TIME_AFTER_BAUDRATE_UPDATE);
+
+	err = fw_upload_uart_reconfig(operation_speed, flowcontrol_of_hci);
+	if (err) {
+		LOG_ERR("Fail to update uart bandrate");
+		return err;
+	}
+
+	return 0;
+}