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>

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 6d6537d09d4f098e05d6f6231d50aeca8003e069..5000586cb98da2331b0cbe1c31ec26b0f6f40eb4 100644 (file)
--- 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)