dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.
The dma_request_chan() is the standard API to request slave channel,
clients should be moved away from the legacy API to allow us to retire
them.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
        if (st->dma_st.dma_chan)
                return;
 
-       st->dma_st.dma_chan = dma_request_slave_channel(&pdev->dev, "rx");
-
-       if (!st->dma_st.dma_chan)  {
+       st->dma_st.dma_chan = dma_request_chan(&pdev->dev, "rx");
+       if (IS_ERR(st->dma_st.dma_chan))  {
                dev_info(&pdev->dev, "can't get DMA channel\n");
+               st->dma_st.dma_chan = NULL;
                goto dma_exit;
        }