From 78e8fa2972e5583bdda8103925217f5e1215b767 Mon Sep 17 00:00:00 2001 From: Balakrishna Godavarthi Date: Mon, 4 Feb 2019 20:36:42 +0530 Subject: Bluetooth: hci_qca: Deassert RTS while baudrate change command This patch will help to stop frame reassembly errors while changing the baudrate. This is because host send a change baudrate request command to the chip with 115200 bps, Whereas chip will change their UART clocks to the enable for new baudrate and sends the response for the change request command with newer baudrate, On host side we are still operating in 115200 bps which results of reading garbage data. Here we are pulling RTS line, so that chip we will wait to send data to host until host change its baudrate. Signed-off-by: Balakrishna Godavarthi Tested-by: Matthias Kaehlcke Reviewed-by: Matthias Kaehlcke Signed-off-by: Marcel Holtmann --- drivers/bluetooth/hci_qca.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index 9a1c0a71b460..e3cf0dbfc89d 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -964,7 +964,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) struct hci_uart *hu = hci_get_drvdata(hdev); struct qca_data *qca = hu->priv; struct sk_buff *skb; - struct qca_serdev *qcadev; u8 cmd[] = { 0x01, 0x48, 0xFC, 0x01, 0x00 }; if (baudrate > QCA_BAUDRATE_3200000) @@ -978,13 +977,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) return -ENOMEM; } - /* Disabling hardware flow control is mandatory while - * sending change baudrate request to wcn3990 SoC. - */ - qcadev = serdev_device_get_drvdata(hu->serdev); - if (qcadev->btsoc_type == QCA_WCN3990) - hci_uart_set_flow_control(hu, true); - /* Assign commands to change baudrate and packet type. */ skb_put_data(skb, cmd, sizeof(cmd)); hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; @@ -1000,9 +992,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS)); set_current_state(TASK_RUNNING); - if (qcadev->btsoc_type == QCA_WCN3990) - hci_uart_set_flow_control(hu, false); - return 0; } @@ -1089,7 +1078,8 @@ static int qca_check_speeds(struct hci_uart *hu) static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type) { unsigned int speed, qca_baudrate; - int ret; + struct qca_serdev *qcadev; + int ret = 0; if (speed_type == QCA_INIT_SPEED) { speed = qca_get_speed(hu, QCA_INIT_SPEED); @@ -1100,16 +1090,27 @@ static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type) if (!speed) return 0; + /* Disable flow control for wcn3990 to deassert RTS while + * changing the baudrate of chip and host. + */ + qcadev = serdev_device_get_drvdata(hu->serdev); + if (qcadev->btsoc_type == QCA_WCN3990) + hci_uart_set_flow_control(hu, true); + qca_baudrate = qca_get_baudrate_value(speed); bt_dev_dbg(hu->hdev, "Set UART speed to %d", speed); ret = qca_set_baudrate(hu->hdev, qca_baudrate); if (ret) - return ret; + goto error; host_set_baudrate(hu, speed); + +error: + if (qcadev->btsoc_type == QCA_WCN3990) + hci_uart_set_flow_control(hu, false); } - return 0; + return ret; } static int qca_wcn3990_init(struct hci_uart *hu) -- cgit v1.2.3