dmaengine: fsl-edma: Fix clock handling error paths

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>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
index be2e62b879481f592aa965d4fe165b4ae8771896..7208fc906ac1e9bf77abe147fcb323efbe268249 100644 (file)
--- 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;
 }