dmaengine: imx-dma: Check for clk_prepare_enable() error

clk_prepare_enable() may fail, so we should better check its return value
and propagate it in the case of error.

While at it, change the label 'err' to a more descriptive naming.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/imx-dma.c

@@ -1083,8 +1083,12 @@ static int __init imxdma_probe(struct platform_device *pdev)
 	if (IS_ERR(imxdma->dma_ahb))
 		return PTR_ERR(imxdma->dma_ahb);
 
-	clk_prepare_enable(imxdma->dma_ipg);
-	clk_prepare_enable(imxdma->dma_ahb);
+	ret = clk_prepare_enable(imxdma->dma_ipg);
+	if (ret)
+		return ret;
+	ret = clk_prepare_enable(imxdma->dma_ahb);
+	if (ret)
+		goto disable_dma_ipg_clk;
 
 	/* reset DMA module */
 	imx_dmav1_writel(imxdma, DCR_DRST, DMA_DCR);
@@ -1094,20 +1098,20 @@ static int __init imxdma_probe(struct platform_device *pdev)
 				       dma_irq_handler, 0, "DMA", imxdma);
 		if (ret) {
 			dev_warn(imxdma->dev, "Can't register IRQ for DMA\n");
-			goto err;
+			goto disable_dma_ahb_clk;
 		}
 
 		irq_err = platform_get_irq(pdev, 1);
 		if (irq_err < 0) {
 			ret = irq_err;
-			goto err;
+			goto disable_dma_ahb_clk;
 		}
 
 		ret = devm_request_irq(&pdev->dev, irq_err,
 				       imxdma_err_handler, 0, "DMA", imxdma);
 		if (ret) {
 			dev_warn(imxdma->dev, "Can't register ERRIRQ for DMA\n");
-			goto err;
+			goto disable_dma_ahb_clk;
 		}
 	}
 
@@ -1144,7 +1148,7 @@ static int __init imxdma_probe(struct platform_device *pdev)
 				dev_warn(imxdma->dev, "Can't register IRQ %d "
 					 "for DMA channel %d\n",
 					 irq + i, i);
-				goto err;
+				goto disable_dma_ahb_clk;
 			}
 			init_timer(&imxdmac->watchdog);
 			imxdmac->watchdog.function = &imxdma_watchdog;
@@ -1190,7 +1194,7 @@ static int __init imxdma_probe(struct platform_device *pdev)
 	ret = dma_async_device_register(&imxdma->dma_device);
 	if (ret) {
 		dev_err(&pdev->dev, "unable to register\n");
-		goto err;
+		goto disable_dma_ahb_clk;
 	}
 
 	if (pdev->dev.of_node) {
@@ -1206,9 +1210,10 @@ static int __init imxdma_probe(struct platform_device *pdev)
 
 err_of_dma_controller:
 	dma_async_device_unregister(&imxdma->dma_device);
-err:
-	clk_disable_unprepare(imxdma->dma_ipg);
+disable_dma_ahb_clk:
 	clk_disable_unprepare(imxdma->dma_ahb);
+disable_dma_ipg_clk:
+	clk_disable_unprepare(imxdma->dma_ipg);
 	return ret;
 }