diff options
author | Cheick Traore <cheick.traore@foss.st.com> | 2025-03-20 16:25:40 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-03-20 08:30:44 -0700 |
commit | 2790ce23951f0c497810c44ad60a126a59c8d84c (patch) | |
tree | 8676e82d75eca47425581fe65ca640f8f5d65f28 | |
parent | 3d5390f4dbe633472b2a4824e66ca5c4eac6fb19 (diff) |
serial: stm32: do not deassert RS485 RTS GPIO prematurely
If stm32_usart_start_tx is called with an empty xmit buffer, RTS GPIO
could be deasserted prematurely, as bytes in TX FIFO are still
transmitting.
So this patch remove rts disable when xmit buffer is empty.
Fixes: d7c76716169d ("serial: stm32: Use TC interrupt to deassert GPIO RTS in RS485 mode")
Cc: stable <stable@kernel.org>
Signed-off-by: Cheick Traore <cheick.traore@foss.st.com>
Link: https://lore.kernel.org/r/20250320152540.709091-1-cheick.traore@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/tty/serial/stm32-usart.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 4c97965ec43b..ad06b760cfca 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -965,10 +965,8 @@ static void stm32_usart_start_tx(struct uart_port *port) { struct tty_port *tport = &port->state->port; - if (kfifo_is_empty(&tport->xmit_fifo) && !port->x_char) { - stm32_usart_rs485_rts_disable(port); + if (kfifo_is_empty(&tport->xmit_fifo) && !port->x_char) return; - } stm32_usart_rs485_rts_enable(port); |