spi/s3c64xx: Check for errors in dmaengine prepare_transfer()

Don't silently ignore errors, report them.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 25 insertions, 1 deletions

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 6d6537d09d4f..5000586cb98d 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -421,6 +421,7 @@ static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
         dma_filter_fn filter = sdd->cntrlr_info->filter;
         struct device *dev = &sdd->pdev->dev;
         dma_cap_mask_t mask;
+        int ret;
 
         dma_cap_zero(mask);
         dma_cap_set(DMA_SLAVE, mask);
@@ -428,11 +429,34 @@ static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
         /* Acquire DMA channels */
         sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
                                 (void*)sdd->rx_dma.dmach, dev, "rx");
+        if (!sdd->rx_dma.ch) {
+                dev_err(dev, "Failed to get RX DMA channel\n");
+                ret = -EBUSY;
+                goto out;
+        }
+
         sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
                                 (void*)sdd->tx_dma.dmach, dev, "tx");
-        pm_runtime_get_sync(&sdd->pdev->dev);
+        if (!sdd->tx_dma.ch) {
+                dev_err(dev, "Failed to get TX DMA channel\n");
+                ret = -EBUSY;
+                goto out_rx;
+        }
+
+        ret = pm_runtime_get_sync(&sdd->pdev->dev);
+        if (ret != 0) {
+                dev_err(dev, "Failed to enable device: %d\n", ret);
+                goto out_tx;
+        }
 
         return 0;
+
+out_tx:
+        dma_release_channel(sdd->tx_dma.ch);
+out_rx:
+        dma_release_channel(sdd->rx_dma.ch);
+out:
+        return ret;
 }
 
 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)