diff options
| author | Lino Sanfilippo <l.sanfilippo@kunbus.com> | 2023-01-08 19:17:35 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-19 14:54:58 +0100 |
| commit | 4f39aca2360c82dccd2f5179d77e94aab665bea6 (patch) | |
| tree | b65022ecac134684ec6e764fdef18816b16ff29a | |
| parent | e8914b52e5b024e4af3d810a935fe0805eee8a36 (diff) | |
serial: amba-pl011: fix high priority character transmission in rs486 mode
In RS485 mode the transmission of a high priority character fails since it
is written to the data register before the transmitter is enabled. Fix this
in pl011_tx_chars() by enabling RS485 transmission before writing the
character.
Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support")
Cc: stable@vger.kernel.org
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20230108181735.10937-1-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/amba-pl011.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index d75c39f4622b..d8c2f3455eeb 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1466,6 +1466,10 @@ static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) struct circ_buf *xmit = &uap->port.state->xmit; int count = uap->fifosize >> 1; + if ((uap->port.rs485.flags & SER_RS485_ENABLED) && + !uap->rs485_tx_started) + pl011_rs485_tx_start(uap); + if (uap->port.x_char) { if (!pl011_tx_char(uap, uap->port.x_char, from_irq)) return true; @@ -1477,10 +1481,6 @@ static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) return false; } - if ((uap->port.rs485.flags & SER_RS485_ENABLED) && - !uap->rs485_tx_started) - pl011_rs485_tx_start(uap); - /* If we are using DMA mode, try to send some characters. */ if (pl011_dma_tx_irq(uap)) return true; |