patch "serial: samsung: wait for transfer completion before clock disable" added to tty-next

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This is a note to let you know that I've just added the patch titled

    serial: samsung: wait for transfer completion before clock disable

to my tty git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git
in the tty-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


>From 1ff383a4c3eda8893ec61b02831826e1b1f46b41 Mon Sep 17 00:00:00 2001
From: Robert Baldyga <r.baldyga@xxxxxxxxxxx>
Date: Mon, 24 Nov 2014 07:56:21 +0100
Subject: serial: samsung: wait for transfer completion before clock disable

This patch adds waiting until transmit buffer and shifter will be empty
before clock disabling.

Without this fix it's possible to have clock disabled while data was
not transmited yet, which causes unproper state of TX line and problems
in following data transfers.

Cc: <stable@xxxxxxxxxxxxxxx> # v2.6.26+
Signed-off-by: Robert Baldyga <r.baldyga@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/tty/serial/samsung.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 796c04c77dc1..d36b2bd39e30 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -559,11 +559,15 @@ static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
 			      unsigned int old)
 {
 	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	int timeout = 10000;
 
 	ourport->pm_level = level;
 
 	switch (level) {
 	case 3:
+		while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
+			udelay(100);
+
 		if (!IS_ERR(ourport->baudclk))
 			clk_disable_unprepare(ourport->baudclk);
 
-- 
2.1.3


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