From: Erwan Le Ray <erwan.leray@xxxxxx> [ Upstream commit b83b957c91f68e53f0dc596e129e8305761f2a32 ] Disables the tx irq when the transmission is ended and updates stop_tx conditions for code cleanup. Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Signed-off-by: Erwan Le Ray <erwan.leray@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/tty/serial/stm32-usart.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 0a7953e5ce47..2e7757d5e5d8 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -420,13 +420,8 @@ static void stm32_transmit_chars(struct uart_port *port) return; } - if (uart_tx_stopped(port)) { - stm32_stop_tx(port); - return; - } - - if (uart_circ_empty(xmit)) { - stm32_stop_tx(port); + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + stm32_clr_bits(port, ofs->cr1, USART_CR1_TXEIE); return; } @@ -439,7 +434,7 @@ static void stm32_transmit_chars(struct uart_port *port) uart_write_wakeup(port); if (uart_circ_empty(xmit)) - stm32_stop_tx(port); + stm32_clr_bits(port, ofs->cr1, USART_CR1_TXEIE); } static irqreturn_t stm32_interrupt(int irq, void *ptr) -- 2.20.1