linux-kernel - [PATCH 4/4] tty: serial: do unlock on a common path in altera_jtaguart_console

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Date:   Tue, 27 Sep 2022 13:18:19 +0200
From:   Jiri Slaby <jslaby@...e.cz>
To:     gregkh@...uxfoundation.org
Cc:     linux-serial@...r.kernel.org, linux-kernel@...r.kernel.org,
        Jiri Slaby <jslaby@...e.cz>,
        Tobias Klauser <tklauser@...tanz.ch>
Subject: [PATCH 4/4] tty: serial: do unlock on a common path in altera_jtaguart_console_putc()

port->lock is unlocked in each branch in altera_jtaguart_console_putc(),
so do it before the "if". "status" needs not be under the lock, as the
register was already read.

Cc: Tobias Klauser <tklauser@...tanz.ch>
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
 drivers/tty/serial/altera_jtaguart.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c
index ac8ce418de36..c2d154d78e54 100644
--- a/drivers/tty/serial/altera_jtaguart.c
+++ b/drivers/tty/serial/altera_jtaguart.c
@@ -310,11 +310,12 @@ static void altera_jtaguart_console_putc(struct uart_port *port, unsigned char c
 
 	spin_lock_irqsave(&port->lock, flags);
 	while (!altera_jtaguart_tx_space(port, &status)) {
+		spin_unlock_irqrestore(&port->lock, flags);
+
 		if ((status & ALTERA_JTAGUART_CONTROL_AC_MSK) == 0) {
-			spin_unlock_irqrestore(&port->lock, flags);
 			return;	/* no connection activity */
 		}
-		spin_unlock_irqrestore(&port->lock, flags);
+
 		cpu_relax();
 		spin_lock_irqsave(&port->lock, flags);
 	}
-- 
2.37.3