[PATCH 1/8] dmaengine: fsl-edma: Fix clock handling error paths

Peter Griffin
2016-06-07T17:38:34Z

Currently fsl-edma doesn't clk_disable_unprepare()
its clocks on error conditions. This patch adds a
fsl_disable_clocks helper for this, and also only
disables clocks which were enabled if encountering
an error whilst enabling clocks.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
---
drivers/dma/fsl-edma.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
index be2e62b..7208fc9 100644
--- a/drivers/dma/fsl-edma.c
+++ b/drivers/dma/fsl-edma.c
@@ -852,6 +852,14 @@ fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma
return 0;
}

+static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma)
+{
+ int i;
+
+ for (i = 0; i < DMAMUX_NR; i++)
+ clk_disable_unprepare(fsl_edma->muxclk[i]);
+}
+
static int fsl_edma_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
@@ -897,6 +905,10 @@ static int fsl_edma_probe(struct platform_device *pdev)

ret = clk_prepare_enable(fsl_edma->muxclk[i]);
if (ret) {
+ /* disable only clks which were enabled on error */
+ for (; i >= 0; i--)
+ clk_disable_unprepare(fsl_edma->muxclk[i]);
+
dev_err(&pdev->dev, "DMAMUX clk block failed.\n");
return ret;
}
@@ -952,6 +964,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
ret = dma_async_device_register(&fsl_edma->dma_dev);
if (ret) {
dev_err(&pdev->dev, "Can't register Freescale eDMA engine.\n");
+ fsl_disable_clocks(fsl_edma);
return ret;
}

@@ -959,6 +972,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
if (ret) {
dev_err(&pdev->dev, "Can't register Freescale eDMA of_dma.\n");
dma_async_device_unregister(&fsl_edma->dma_dev);
+ fsl_disable_clocks(fsl_edma);
return ret;
}

@@ -972,13 +986,10 @@ static int fsl_edma_remove(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
- int i;

of_dma_controller_free(np);
dma_async_device_unregister(&fsl_edma->dma_dev);
-
- for (i = 0; i < DMAMUX_NR; i++)
- clk_disable_unprepare(fsl_edma->muxclk[i]);
+ fsl_disable_clocks(fsl_edma);

return 0;
}
--
1.9.1