From d9c128117da41cf4cb0e80ae565b5d3ac79dffac Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Tue, 20 Sep 2022 07:20:42 +0200
Subject: [PATCH] tty: serial: clean up stop-tx part in altera_uart_tx_chars()
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Git-commit: d9c128117da41cf4cb0e80ae565b5d3ac79dffac
Patch-mainline: v6.1-rc1
References: git-fixes

The "stop TX" path in altera_uart_tx_chars() is open-coded, so:
* use uart_circ_empty() to check if the buffer is empty, and
* when true, call altera_uart_stop_tx().

Cc: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220920052049.20507-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/tty/serial/altera_uart.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index a38db2cb8dc1..4170e66601ec 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -272,10 +272,8 @@ static void altera_uart_tx_chars(struct altera_uart *pp)
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
 
-	if (xmit->head == xmit->tail) {
-		pp->imr &= ~ALTERA_UART_CONTROL_TRDY_MSK;
-		altera_uart_update_ctrl_reg(pp);
-	}
+	if (uart_circ_empty(xmit))
+		altera_uart_stop_tx(port);
 }
 
 static irqreturn_t altera_uart_interrupt(int irq, void *data)
-- 
2.35.3