1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 55dc00dd0e5e..d984a97043b3 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -322,7 +322,22 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *
                         .src_maxburst = uap->fifosize >> 2,
                         .device_fc = false,
                 };
+                struct dma_slave_caps caps;
 
+                /*
+                 * Some DMA controllers provide information on their capabilities.
+                 * If the controller does, check for suitable residue processing
+                 * otherwise assime all is well.
+                 */
+                if (0 == dma_get_slave_caps(chan, &caps)) {
+                        if (caps.residue_granularity ==
+                                        DMA_RESIDUE_GRANULARITY_DESCRIPTOR) {
+                                dma_release_channel(chan);
+                                dev_info(uap->port.dev,
+                                        "RX DMA disabled - no residue processing\n");
+                                return;
+                        }
+                }
                 dmaengine_slave_config(chan, &rx_conf);
                 uap->dmarx.chan = chan;