serial: 8250_dma: Fix RX handling

Overrun, parity and framing errors should be handled in
8250_core. This also adds check for the dma_status and exits
if the channel is not idle.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 16 insertions, 7 deletions

diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c
index ce2518d5dfd1..66430614510a 100644
--- a/drivers/tty/serial/8250/8250_dma.c
+++ b/drivers/tty/serial/8250/8250_dma.c
@@ -101,20 +101,29 @@ int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
         struct dma_tx_state             state;
         int                             dma_status;
 
-        /*
-         * If RCVR FIFO trigger level was not reached, complete the transfer and
-         * let 8250.c copy the remaining data.
-         */
-        if ((iir & 0x3f) == UART_IIR_RX_TIMEOUT) {
-                dma_status = dmaengine_tx_status(dma->rxchan, dma->rx_cookie,
-                                                &state);
+        dma_status = dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state);
+
+        switch (iir & 0x3f) {
+        case UART_IIR_RLSI:
+                /* 8250_core handles errors and break interrupts */
+                return -EIO;
+        case UART_IIR_RX_TIMEOUT:
+                /*
+                 * If RCVR FIFO trigger level was not reached, complete the
+                 * transfer and let 8250_core copy the remaining data.
+                 */
                 if (dma_status == DMA_IN_PROGRESS) {
                         dmaengine_pause(dma->rxchan);
                         __dma_rx_complete(p);
                 }
                 return -ETIMEDOUT;
+        default:
+                break;
         }
 
+        if (dma_status)
+                return 0;
+
         desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr,
                                            dma->rx_size, DMA_DEV_TO_MEM,
                                            DMA_PREP_INTERRUPT | DMA_CTRL_ACK);