As a part of system suspend uart_port_suspend is called from the Serial driver, which calls set_mctrl passing mctrl as 0. This makes RFR high(NOT_READY) during suspend. Due to this BT SoC is not able to send wakeup bytes to UART during suspend. Include if check for non-suspend case to keep RFR low during suspend. Signed-off-by: satya priya <skakit@xxxxxxxxxxxxxx> Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> --- Changes in V2: - This patch fixes the UART flow control issue during suspend. Newly added in V2. Changes in V3: - As per Matthias's comment removed the extra parentheses. Changes in V4: - No change. Changes in V5: - As per Matthias comment, fixed nit-pick in commit text. Changes in V6: - No change. drivers/tty/serial/qcom_geni_serial.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 3aa29d2..bc63c54 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -242,7 +242,7 @@ static void qcom_geni_serial_set_mctrl(struct uart_port *uport, if (mctrl & TIOCM_LOOP) port->loopback = RX_TX_CTS_RTS_SORTED; - if (!(mctrl & TIOCM_RTS)) + if (!(mctrl & TIOCM_RTS) && !uport->suspended) uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY; writel(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR); } -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation