can: mcp251x: Use devm_clk_get_optional() to get the input clock

Simplify the code which fetches the input clock by using
devm_clk_get_optional(). This comes with a small functional change: previously
all errors were ignored when platform data is present. Now all errors are
treated as errors. If no input clock is present devm_clk_get_optional() will
return NULL instead of an error which matches the behavior of the old code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

1 files changed, 12 insertions, 18 deletions

diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c
index 6e5831308c70..b5d70826a186 100644
--- a/drivers/net/can/spi/mcp251x.c
+++ b/drivers/net/can/spi/mcp251x.c
@@ -994,15 +994,13 @@ static int mcp251x_can_probe(struct spi_device *spi)
         struct clk *clk;
         int freq, ret;
 
-        clk = devm_clk_get(&spi->dev, NULL);
-        if (IS_ERR(clk)) {
-                if (pdata)
-                        freq = pdata->oscillator_frequency;
-                else
-                        return PTR_ERR(clk);
-        } else {
-                freq = clk_get_rate(clk);
-        }
+        clk = devm_clk_get_optional(&spi->dev, NULL);
+        if (IS_ERR(clk))
+                return PTR_ERR(clk);
+
+        freq = clk_get_rate(clk);
+        if (freq == 0 && pdata)
+                freq = pdata->oscillator_frequency;
 
         /* Sanity check */
         if (freq < 1000000 || freq > 25000000)
@@ -1013,11 +1011,9 @@ static int mcp251x_can_probe(struct spi_device *spi)
         if (!net)
                 return -ENOMEM;
 
-        if (!IS_ERR(clk)) {
-                ret = clk_prepare_enable(clk);
-                if (ret)
-                        goto out_free;
-        }
+        ret = clk_prepare_enable(clk);
+        if (ret)
+                goto out_free;
 
         net->netdev_ops = &mcp251x_netdev_ops;
         net->flags |= IFF_ECHO;
@@ -1102,8 +1098,7 @@ error_probe:
         mcp251x_power_enable(priv->power, 0);
 
 out_clk:
-        if (!IS_ERR(clk))
-                clk_disable_unprepare(clk);
+        clk_disable_unprepare(clk);
 
 out_free:
         free_candev(net);
@@ -1121,8 +1116,7 @@ static int mcp251x_can_remove(struct spi_device *spi)
 
         mcp251x_power_enable(priv->power, 0);
 
-        if (!IS_ERR(priv->clk))
-                clk_disable_unprepare(priv->clk);
+        clk_disable_unprepare(priv->clk);
 
         free_candev(net);