[PATCH v3] serial: samsung: honor fifosize from dts at first

[Tamseel Shams <m.shams@xxxxxxxxxxx>]

Currently for platforms which passes UART fifosize from DT gets
override by local driver structure "s3c24xx_serial_drv_data",
which is not intended. Change the code to honor fifosize from
device tree at first.

Signed-off-by: Tamseel Shams <m.shams@xxxxxxxxxxx>
---
Change Log:
v1 -> v2:
Acknowledged Krzysztof's comments
Initialized "ret" variable

v2 -> v3:
intoduced new variable "fifosize_prop" to handle
return value from call of "of_property_read_u32"

 drivers/tty/serial/samsung_tty.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index 71d17d804fda..745702ec8eda 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -1952,7 +1952,7 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
 	struct device_node *np = pdev->dev.of_node;
 	struct s3c24xx_uart_port *ourport;
 	int index = probe_index;
-	int ret, prop = 0;
+	int ret, prop = 0, fifosize_prop = 1;
 
 	if (np) {
 		ret = of_alias_get_id(np, "serial");
@@ -1990,8 +1990,8 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
 	}
 
 	if (np) {
-		of_property_read_u32(np,
-			"samsung,uart-fifosize", &ourport->port.fifosize);
+		fifosize_prop = of_property_read_u32(np, "samsung,uart-fifosize",
+				&ourport->port.fifosize);
 
 		if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
 			switch (prop) {
@@ -2009,10 +2009,13 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
 		}
 	}
 
-	if (ourport->drv_data->fifosize[index])
-		ourport->port.fifosize = ourport->drv_data->fifosize[index];
-	else if (ourport->info->fifosize)
-		ourport->port.fifosize = ourport->info->fifosize;
+	if (fifosize_prop) {
+		if (ourport->drv_data->fifosize[index])
+			ourport->port.fifosize = ourport->drv_data->fifosize[index];
+		else if (ourport->info->fifosize)
+			ourport->port.fifosize = ourport->info->fifosize;
+	}
+
 	ourport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SAMSUNG_CONSOLE);
 
 	/*
-- 
2.17.1