dmaengine: qcom: bam_dma: make bam clk optional

When BAM is remotely controlled it does not sound correct to control
its clk on Linux side. Make it optional, so that its not mandatory
for remote controlled BAM instances.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/qcom/bam_dma.c

@@ -1233,8 +1233,12 @@ static int bam_dma_probe(struct platform_device *pdev)
 						"qcom,controlled-remotely");
 
 	bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
-	if (IS_ERR(bdev->bamclk))
-		return PTR_ERR(bdev->bamclk);
+	if (IS_ERR(bdev->bamclk)) {
+		if (!bdev->controlled_remotely)
+			return PTR_ERR(bdev->bamclk);
+
+		bdev->bamclk = NULL;
+	}
 
 	ret = clk_prepare_enable(bdev->bamclk);
 	if (ret) {