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From:   Gabriel Somlo <gsomlo@gmail.com>
To:     linux-kernel@vger.kernel.org
Cc:     linux-serial@vger.kernel.org, gregkh@linuxfoundation.org,
        jirislaby@kernel.org, kgugala@antmicro.com, mholenko@antmicro.com,
        joel@jms.id.au, david.abdurachmanov@gmail.com,
        florent@enjoy-digital.fr, geert@linux-m68k.org,
        ilpo.jarvinen@linux.intel.com
Subject: [PATCH v5 07/14] serial: liteuart: rx loop should only ack rx events
Date:   Fri, 18 Nov 2022 09:55:05 -0500
Message-Id: <20221118145512.509950-8-gsomlo@gmail.com>
In-Reply-To: <20221118145512.509950-1-gsomlo@gmail.com>
References: <20221118145512.509950-1-gsomlo@gmail.com>
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While receiving characters, it is necessary to acknowledge each one
by writing to the EV_PENDING register's EV_RX bit. Ensure we do not
also gratuitously set the EV_TX bit in the process.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
---
 drivers/tty/serial/liteuart.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c
index 81a86c5eb393..c90ab65fbdcf 100644
--- a/drivers/tty/serial/liteuart.c
+++ b/drivers/tty/serial/liteuart.c
@@ -82,7 +82,7 @@ static void liteuart_timer(struct timer_list *t)
 		port->icount.rx++;
 
 		/* necessary for RXEMPTY to refresh its value */
-		litex_write8(membase + OFF_EV_PENDING, EV_TX | EV_RX);
+		litex_write8(membase + OFF_EV_PENDING, EV_RX);
 
 		/* no overflow bits in status */
 		if (!(uart_handle_sysrq_char(port, ch)))
-- 
2.38.1