ENGR00322581-01 tty: serial: imx: use workque to increase tx performance

Use workque to submit tx dma request to increase tx performance.

Signed-off-by: Robin Gong <b38343@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 5ecaee07cbac..e08ed72e4b99 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -226,6 +226,7 @@ struct imx_port {
         void                    *rx_buf;
         unsigned int            tx_bytes;
         unsigned int            dma_tx_nents;
+        struct work_struct      tsk_dma_tx;
         wait_queue_head_t       dma_wait;
         unsigned int            saved_reg[11];
 };
@@ -506,6 +507,8 @@ static void dma_tx_callback(void *data)
 
         uart_write_wakeup(&sport->port);
 
+        schedule_work(&sport->tsk_dma_tx);
+
         if (waitqueue_active(&sport->dma_wait)) {
                 wake_up(&sport->dma_wait);
                 dev_dbg(sport->port.dev, "exit in %s.\n", __func__);
@@ -513,8 +516,9 @@ static void dma_tx_callback(void *data)
         }
 }
 
-static void imx_dma_tx(struct imx_port *sport)
+static void dma_tx_work(struct work_struct *w)
 {
+        struct imx_port *sport = container_of(w, struct imx_port, tsk_dma_tx);
         struct circ_buf *xmit = &sport->port.state->xmit;
         struct scatterlist *sgl = sport->tx_sgl;
         struct dma_async_tx_descriptor *desc;
@@ -605,7 +609,7 @@ static void imx_start_tx(struct uart_port *port)
         }
 
         if (sport->dma_is_enabled) {
-                imx_dma_tx(sport);
+                schedule_work(&sport->tsk_dma_tx);
                 return;
         }
 
@@ -1147,6 +1151,8 @@ static int imx_startup(struct uart_port *port)
                 }
         }
 
+        INIT_WORK(&sport->tsk_dma_tx, dma_tx_work);
+
         spin_lock_irqsave(&sport->port.lock, flags);
         /*
          * Finally, clear and enable interrupts