This is a note to let you know that I've just added the patch titled
tty: serial: clean up stop-tx part in altera_uart_tx_chars()
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tty-serial-clean-up-stop-tx-part-in-altera_uart_tx_c.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 68a86ac83c368467c6497aef658a77f367c58693
Author: Jiri Slaby <jirislaby@xxxxxxxxxx>
Date: Tue Sep 20 07:20:42 2022 +0200
tty: serial: clean up stop-tx part in altera_uart_tx_chars()
[ Upstream commit d9c128117da41cf4cb0e80ae565b5d3ac79dffac ]
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@xxxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Acked-by: Tobias Klauser <tklauser@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
Link: https://lore.kernel.org/r/20220920052049.20507-3-jslaby@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Stable-dep-of: 1307c5d33cce ("serial: altera_uart: fix locking in polling mode")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 0e487ce091ac..508a3c2b7781 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -274,10 +274,8 @@ 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)
