dmaengine: qcom: bam_dma: check if the runtime pm enabled

Disabling pm runtime at probe is not sufficient to get BAM working
on remotely controller instances. pm_runtime_get_sync() would return
-EACCES in such cases.
So check if runtime pm is enabled before returning error from bam functions.

Fixes: 5b4a6895 ("dmaengine: qcom: bam_dma: disable runtime pm on remote controlled")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/qcom/bam_dma.c

@@ -524,6 +524,14 @@ static int bam_alloc_chan(struct dma_chan *chan)
 	return 0;
 }
 
+static int bam_pm_runtime_get_sync(struct device *dev)
+{
+	if (pm_runtime_enabled(dev))
+		return pm_runtime_get_sync(dev);
+
+	return 0;
+}
+
 /**
  * bam_free_chan - Frees dma resources associated with specific channel
  * @chan: specified channel
@@ -539,7 +547,7 @@ static void bam_free_chan(struct dma_chan *chan)
 	unsigned long flags;
 	int ret;
 
-	ret = pm_runtime_get_sync(bdev->dev);
+	ret = bam_pm_runtime_get_sync(bdev->dev);
 	if (ret < 0)
 		return;
 
@@ -720,7 +728,7 @@ static int bam_pause(struct dma_chan *chan)
 	unsigned long flag;
 	int ret;
 
-	ret = pm_runtime_get_sync(bdev->dev);
+	ret = bam_pm_runtime_get_sync(bdev->dev);
 	if (ret < 0)
 		return ret;
 
@@ -746,7 +754,7 @@ static int bam_resume(struct dma_chan *chan)
 	unsigned long flag;
 	int ret;
 
-	ret = pm_runtime_get_sync(bdev->dev);
+	ret = bam_pm_runtime_get_sync(bdev->dev);
 	if (ret < 0)
 		return ret;
 
@@ -852,7 +860,7 @@ static irqreturn_t bam_dma_irq(int irq, void *data)
 	if (srcs & P_IRQ)
 		tasklet_schedule(&bdev->task);
 
-	ret = pm_runtime_get_sync(bdev->dev);
+	ret = bam_pm_runtime_get_sync(bdev->dev);
 	if (ret < 0)
 		return ret;
 
@@ -969,7 +977,7 @@ static void bam_start_dma(struct bam_chan *bchan)
 	if (!vd)
 		return;
 
-	ret = pm_runtime_get_sync(bdev->dev);
+	ret = bam_pm_runtime_get_sync(bdev->dev);
 	if (ret < 0)
 		return;