[PATCH] serial: vt8500: Use devm_clk_get_enabled()

[Wentao Liang]

vt8500_serial_probe() gets the clock with of_clk_get() and enables it
with clk_prepare_enable(), so the reference has to be dropped by hand on
the error path, and the clock is never disabled or released afterwards,
even though the rest of the probe is devm-managed.

Use devm_clk_get_enabled() instead, which gets and enables the clock in
one call and registers the teardown with devm. The manual error handling
and the clk_put() can then go, and probe returns the actual error code
from the clock lookup rather than a hard-coded -EINVAL.

The clock still stays enabled as long as the port is in use, so the
success path is unchanged.
---
 drivers/tty/serial/vt8500_serial.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c
index fc6fdc751b16..73922523dff6 100644
--- a/drivers/tty/serial/vt8500_serial.c
+++ b/drivers/tty/serial/vt8500_serial.c
@@ -603,7 +603,6 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 	struct resource *mmres;
 	struct device_node *np = pdev->dev.of_node;
 	const unsigned int *flags;
-	int ret;
 	int port;
 	int irq;
 
@@ -647,17 +646,10 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 	if (IS_ERR(vt8500_port->uart.membase))
 		return PTR_ERR(vt8500_port->uart.membase);
 
-	vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0);
+	vt8500_port->clk = devm_clk_get_enabled(&pdev->dev, NULL);
 	if (IS_ERR(vt8500_port->clk)) {
 		dev_err(&pdev->dev, "failed to get clock\n");
-		return  -EINVAL;
-	}
-
-	ret = clk_prepare_enable(vt8500_port->clk);
-	if (ret) {
-		dev_err(&pdev->dev, "failed to enable clock\n");
-		clk_put(vt8500_port->clk);
-		return ret;
+		return PTR_ERR(vt8500_port->clk);
 	}
 
 	vt8500_port->vt8500_uart_flags = *flags;
-- 
2.34.1