gpio: stp-xway: improve module clock error handling

Three module clock error handling improvements:
- use devm_clk_get() so the clock instance can be freed if
  devm_gpiochip_add_data() fails later on
- switch to clk_prepare_enable() so the driver is ready whenever the
  lantiq target switches to the common clock framework
- disable the clock again (using clk_disable_unprepare()) if
  devm_gpiochip_add_data()

All of these are virtually no-ops with the current lantiq target.
However, these will be relevant if we switch to the common clock
framework.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20190702223248.31934-3-martin.blumenstingl@googlemail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-stp-xway.c b/drivers/gpio/gpio-stp-xway.c
index 3606af9..cbdeba9 100644 (file)
--- a/drivers/gpio/gpio-stp-xway.c
+++ b/drivers/gpio/gpio-stp-xway.c
@@ -259,18 +259,23 @@ static int xway_stp_probe(struct platform_device *pdev)
        if (!of_find_property(pdev->dev.of_node, "lantiq,rising", NULL))
                chip->edge = XWAY_STP_FALLING;
 
-       clk = clk_get(&pdev->dev, NULL);
+       clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(clk)) {
                dev_err(&pdev->dev, "Failed to get clock\n");
                return PTR_ERR(clk);
        }
-       clk_enable(clk);
+
+       ret = clk_prepare_enable(clk);
+       if (ret)
+               return ret;
 
        xway_stp_hw_init(chip);
 
        ret = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
-       if (ret)
+       if (ret) {
+               clk_disable_unprepare(clk);
                return ret;
+       }
 
        dev_info(&pdev->dev, "Init done\n");