From 90574a5b5a048af7c8c1de8977da498f1e2bdce9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Date: Tue, 7 Jun 2022 11:41:54 +0300 Subject: [PATCH] serial: 8250: handle __start_tx() call in start_tx() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As either start_tx_rs485() or start_tx() calls __start_tx() as the last line of their logic, it makes sense to just move that call into start_tx(). When start_tx_rs485() wants to defer tx using timer, return false so start_tx() can return based on it. Reorganize em485 code in serial8250_start_tx() so that the return can be shared for the cases where tx start is deferred. Signed-off-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20220607084154.8172-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_port.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 448cfbb05f63..a3ffbdfe8fae 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1610,7 +1610,8 @@ void serial8250_em485_start_tx(struct uart_8250_port *up) } EXPORT_SYMBOL_GPL(serial8250_em485_start_tx); -static inline void start_tx_rs485(struct uart_port *port) +/* Returns false, if start_tx_timer was setup to defer TX start */ +static bool start_tx_rs485(struct uart_port *port) { struct uart_8250_port *up = up_to_u8250p(port); struct uart_8250_em485 *em485 = up->em485; @@ -1638,11 +1639,11 @@ static inline void start_tx_rs485(struct uart_port *port) em485->active_timer = &em485->start_tx_timer; start_hrtimer_ms(&em485->start_tx_timer, up->port.rs485.delay_rts_before_send); - return; + return false; } } - __start_tx(port); + return true; } static enum hrtimer_restart serial8250_em485_handle_start_tx(struct hrtimer *t) @@ -1672,14 +1673,12 @@ static void serial8250_start_tx(struct uart_port *port) serial8250_rpm_get_tx(up); - if (em485 && - em485->active_timer == &em485->start_tx_timer) - return; - - if (em485) - start_tx_rs485(port); - else - __start_tx(port); + if (em485) { + if ((em485->active_timer == &em485->start_tx_timer) || + !start_tx_rs485(port)) + return; + } + __start_tx(port); } static void serial8250_throttle(struct uart_port *port)