2016-03-23 08:58:09

by Yegor Yefremov

Subject: [PATCH] Fixes: e490c9144cfa ("tty: Add software emulated RS485 support for 8250")

From: Yegor Yefremov <[email protected]>

When in half-duplex mode RX will be disabled before TX, but not
enabled after deactivating transmitter. This patch enables
UART_IER_RLSI and UART_IER_RDI interrupts after TX is over.

Cc: Matwey V. Kornilov <[email protected]>
Signed-off-by: Yegor Yefremov <[email protected]>
---
drivers/tty/serial/8250/8250_port.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index e213da0..00ad263 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -1403,9 +1403,18 @@ static void __do_stop_tx_rs485(struct uart_8250_port *p)
/*
* Empty the RX FIFO, we are not interested in anything
* received during the half-duplex transmission.
+ * Enable previously disabled RX interrupts.
*/
- if (!(p->port.rs485.flags & SER_RS485_RX_DURING_TX))
+ if (!(p->port.rs485.flags & SER_RS485_RX_DURING_TX)) {
serial8250_clear_fifos(p);
+
+ serial8250_rpm_get(p);
+
+ p->ier |= UART_IER_RLSI | UART_IER_RDI;
+ serial_port_out(&p->port, UART_IER, p->ier);
+
+ serial8250_rpm_put(p);
+ }
}

static void serial8250_em485_handle_stop_tx(unsigned long arg)
--
2.1.4

2016-03-24 07:22:24

by Uwe Kleine-König

Subject: Re: [PATCH] Fixes: e490c9144cfa ("tty: Add software emulated RS485 support for 8250")

Hello,

the subject doesn't look suitable. The Fixes:-line belongs into the
S-o-b paragraph, not the title.

Best regards
Uwe

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