#define DMA_RX_XCOUNT          512
 #define DMA_RX_YCOUNT          (PAGE_SIZE / DMA_RX_XCOUNT)
 
-#define DMA_RX_FLUSH_JIFFIES   5
+#define DMA_RX_FLUSH_JIFFIES   (HZ / 50)
 
 #ifdef CONFIG_SERIAL_BFIN_DMA
 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
 {
        struct circ_buf *xmit = &uart->port.info->xmit;
        unsigned short ier;
-       int flags = 0;
 
        uart->tx_done = 0;
 
 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
 {
        int x_pos, pos;
-       int flags = 0;
 
-       spin_lock_irqsave(&uart->port.lock, flags);
        uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
        x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
        uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
                bfin_serial_dma_rx_chars(uart);
                uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
        }
-       spin_unlock_irqrestore(&uart->port.lock, flags);
+
        uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
        add_timer(&(uart->rx_dma_timer));
 }
 {
        struct bfin_serial_port *uart = dev_id;
        unsigned short irqstat;
-       int pos;
-
-       uart->rx_dma_nrows = DMA_RX_YCOUNT -
-               get_dma_curr_ycount(uart->rx_dma_channel);
-       pos = DMA_RX_XCOUNT * uart->rx_dma_nrows;
-       if (pos != uart->rx_dma_buf.tail) {
-               uart->rx_dma_buf.head = pos;
-               bfin_serial_dma_rx_chars(uart);
-               uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
-       }
 
        spin_lock(&uart->port.lock);
        irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
        clear_dma_irqstat(uart->rx_dma_channel);
-
        spin_unlock(&uart->port.lock);
+
+       del_timer(&(uart->rx_dma_timer));
+       uart->rx_dma_timer.expires = jiffies;
+       add_timer(&(uart->rx_dma_timer));
+
        return IRQ_HANDLED;
 }
 #endif