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>
---
The order with devm_spi_release_controller() (which undoes
devm_spi_alloc_master()) is reversed, but I don't think it is an issue.
---
drivers/spi/spi-mt7621.c | 14 +-------------
1 file changed, 1 insertion(+), 13 deletions(-)
diff --git a/drivers/spi/spi-mt7621.c b/drivers/spi/spi-mt7621.c
index 351b0ef52bbc..2580b28042be 100644
--- 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;
}
--
2.34.1
Il 27/08/22 13:42, Christophe JAILLET ha scritto: > 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> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
On 27/08/2022 13:42, Christophe JAILLET wrote: > 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> > --- > The order with devm_spi_release_controller() (which undoes > devm_spi_alloc_master()) is reversed, but I don't think it is an issue. > --- > drivers/spi/spi-mt7621.c | 14 +------------- > 1 file changed, 1 insertion(+), 13 deletions(-) > > diff --git a/drivers/spi/spi-mt7621.c b/drivers/spi/spi-mt7621.c > index 351b0ef52bbc..2580b28042be 100644 > --- 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; > }
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