spi: mt7621: Use the devm_clk_get_enabled() helper to simplify error handling

The devm_clk_get_enabled() helper:
   - calls devm_clk_get()
   - calls clk_prepare_enable() and registers what is needed in order to
     call clk_disable_unprepare() when needed, as a managed resource.

This helper is well suited for cases where the clock would be kept
prepared or enabled for the whole lifetime of the driver.

This simplifies the error handling a lot.

The order between spi_unregister_controller() (in the remove function) and
the clk_disable_unprepare() (now handle by a  managed resource) is kept
the same.
(see commit 46b5c4fb87ce ("spi: mt7621: Don't leak SPI master in probe
error path") to see why it matters)

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/05a7fd22719008c8a905d6328aa9548ce40f2a7a.1661599671.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-mt7621.c b/drivers/spi/spi-mt7621.c
index 351b0ef..2580b28 100644 (file)
--- a/drivers/spi/spi-mt7621.c
+++ b/drivers/spi/spi-mt7621.c
@@ -327,7 +327,6 @@ static int mt7621_spi_probe(struct platform_device *pdev)
        struct spi_controller *master;
        struct mt7621_spi *rs;
        void __iomem *base;
-       int status = 0;
        struct clk *clk;
        int ret;
 
@@ -339,19 +338,14 @@ static int mt7621_spi_probe(struct platform_device *pdev)
        if (IS_ERR(base))
                return PTR_ERR(base);
 
-       clk = devm_clk_get(&pdev->dev, NULL);
+       clk = devm_clk_get_enabled(&pdev->dev, NULL);
        if (IS_ERR(clk))
                return dev_err_probe(&pdev->dev, PTR_ERR(clk),
                                     "unable to get SYS clock\n");
 
-       status = clk_prepare_enable(clk);
-       if (status)
-               return status;
-
        master = devm_spi_alloc_master(&pdev->dev, sizeof(*rs));
        if (!master) {
                dev_info(&pdev->dev, "master allocation failed\n");
-               clk_disable_unprepare(clk);
                return -ENOMEM;
        }
 
@@ -376,13 +370,10 @@ static int mt7621_spi_probe(struct platform_device *pdev)
        ret = device_reset(&pdev->dev);
        if (ret) {
                dev_err(&pdev->dev, "SPI reset failed!\n");
-               clk_disable_unprepare(clk);
                return ret;
        }
 
        ret = spi_register_controller(master);
-       if (ret)
-               clk_disable_unprepare(clk);
 
        return ret;
 }
@@ -390,13 +381,10 @@ static int mt7621_spi_probe(struct platform_device *pdev)
 static int mt7621_spi_remove(struct platform_device *pdev)
 {
        struct spi_controller *master;
-       struct mt7621_spi *rs;
 
        master = dev_get_drvdata(&pdev->dev);
-       rs = spi_controller_get_devdata(master);
 
        spi_unregister_controller(master);
-       clk_disable_unprepare(rs->clk);
 
        return 0;
 }