From 60e93575476f90a72146b51283f514da655410a7 Mon Sep 17 00:00:00 2001
From: Chander Kashyap <chander.kashyap@linaro.org>
Date: Tue, 28 May 2013 18:32:07 +0530
Subject: [PATCH] serial: samsung: enable clock before clearing pending
interrupts during init
Ensure that the uart controller clock is enabled prior to writing to the
interrupt mask and pending registers in the s3c24xx_serial_init_port
function.
Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/serial/samsung.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 89429410a245..0c8a9fa2be6c 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -1166,6 +1166,18 @@ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
ourport->tx_irq = ret;
ourport->clk = clk_get(&platdev->dev, "uart");
+ if (IS_ERR(ourport->clk)) {
+ pr_err("%s: Controller clock not found\n",
+ dev_name(&platdev->dev));
+ return PTR_ERR(ourport->clk);
+ }
+
+ ret = clk_prepare_enable(ourport->clk);
+ if (ret) {
+ pr_err("uart: clock failed to prepare+enable: %d\n", ret);
+ clk_put(ourport->clk);
+ return ret;
+ }
/* Keep all interrupts masked and cleared */
if (s3c24xx_serial_has_interrupt_mask(port)) {
@@ -1180,6 +1192,7 @@ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
/* reset the fifos (and setup the uart) */
s3c24xx_serial_resetport(port, cfg);
+ clk_disable_unprepare(ourport->clk);
return 0;
}
--
2.20.1