tty/serial: at91: maxburst was missing for dma transfers

commit a8d4e01637902311c5643b69a5c80e2805f04054 upstream.

Maxburst was not set when doing the dma slave configuration. This value
is checked by the recently introduced xdmac. It causes an error when
doing the slave configuration and so prevents from using dma.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 60d05fc2c1c43ab51aefa24d9b752bb7392337f1..0d39ae4ff533201e4050bbedde0e657b14900d33 100644 (file)
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -860,6 +860,7 @@ static int atmel_prepare_tx_dma(struct uart_port *port)
        config.direction = DMA_MEM_TO_DEV;
        config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
        config.dst_addr = port->mapbase + ATMEL_US_THR;
+       config.dst_maxburst = 1;
 
        ret = dmaengine_device_control(atmel_port->chan_tx,
                                        DMA_SLAVE_CONFIG,
@@ -1024,6 +1025,7 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
        config.direction = DMA_DEV_TO_MEM;
        config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
        config.src_addr = port->mapbase + ATMEL_US_RHR;
+       config.src_maxburst = 1;
 
        ret = dmaengine_device_control(atmel_port->chan_rx,
                                        DMA_SLAVE_CONFIG,