diff options
| -rw-r--r-- | drivers/tty/serial/imx.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index dbee7ff2f8fd..cfda31a7edd6 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -975,6 +975,8 @@ static int start_rx_dma(struct imx_port *sport) #define TXTL_DEFAULT 2 /* reset default */ #define RXTL_DEFAULT 1 /* reset default */ +#define TXTL_DMA 8 /* DMA burst setting */ +#define RXTL_DMA 9 /* DMA burst setting */ static void imx_setup_ufcr(struct imx_port *sport, unsigned char txwl, unsigned char rxwl) @@ -1022,7 +1024,8 @@ static int imx_uart_dma_init(struct imx_port *sport) slave_config.direction = DMA_DEV_TO_MEM; slave_config.src_addr = sport->port.mapbase + URXD0; slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; - slave_config.src_maxburst = RXTL_DEFAULT; + /* one byte less than the watermark level to enable the aging timer */ + slave_config.src_maxburst = RXTL_DMA - 1; ret = dmaengine_slave_config(sport->dma_chan_rx, &slave_config); if (ret) { dev_err(dev, "error in RX dma configuration.\n"); @@ -1046,7 +1049,7 @@ static int imx_uart_dma_init(struct imx_port *sport) slave_config.direction = DMA_MEM_TO_DEV; slave_config.dst_addr = sport->port.mapbase + URTX0; slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; - slave_config.dst_maxburst = TXTL_DEFAULT; + slave_config.dst_maxburst = TXTL_DMA; ret = dmaengine_slave_config(sport->dma_chan_tx, &slave_config); if (ret) { dev_err(dev, "error in TX dma configuration."); @@ -1083,6 +1086,8 @@ static void imx_enable_dma(struct imx_port *sport) temp |= UCR4_IDDMAEN; writel(temp, sport->port.membase + UCR4); + imx_setup_ufcr(sport, TXTL_DMA, RXTL_DMA); + sport->dma_is_enabled = 1; } @@ -1105,6 +1110,8 @@ static void imx_disable_dma(struct imx_port *sport) temp &= ~UCR4_IDDMAEN; writel(temp, sport->port.membase + UCR4); + imx_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT); + sport->dma_is_enabled = 0; } |
