serial: samsung: Reorder the sequence of clock control when call s3c24xx_serial_set_termios()

commit b8995f527aac143e83d3900ff39357651ea4e0f6 upstream.

This patch fixes the broken serial log when changing the clock source
of uart device. Before disabling the original clock source, this patch
enables the new clock source to protect the clock off state for a split second.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
This commit is contained in:
Chanwoo Choi 2016-04-21 18:58:31 +09:00 committed by Greg Kroah-Hartman
parent 430b4aab73
commit df8ad62006

View File

@ -1263,6 +1263,8 @@ static void s3c24xx_serial_set_termios(struct uart_port *port,
/* check to see if we need to change clock source */
if (ourport->baudclk != clk) {
clk_prepare_enable(clk);
s3c24xx_serial_setsource(port, clk_sel);
if (!IS_ERR(ourport->baudclk)) {
@ -1270,8 +1272,6 @@ static void s3c24xx_serial_set_termios(struct uart_port *port,
ourport->baudclk = ERR_PTR(-EINVAL);
}
clk_prepare_enable(clk);
ourport->baudclk = clk;
ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
}