1 files changed, 30 insertions, 23 deletions

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index c2816f494807..4fdec6a6b758 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -39,6 +39,7 @@ enum {
         PCH_UART_HANDLED_RX_ERR_INT_SHIFT,
         PCH_UART_HANDLED_RX_TRG_INT_SHIFT,
         PCH_UART_HANDLED_MS_INT_SHIFT,
+        PCH_UART_HANDLED_LS_INT_SHIFT,
 };
 
 enum {
@@ -63,6 +64,8 @@ enum {
                                         PCH_UART_HANDLED_RX_TRG_INT_SHIFT)<<1))
 #define PCH_UART_HANDLED_MS_INT (1<<((PCH_UART_HANDLED_MS_INT_SHIFT)<<1))
 
+#define PCH_UART_HANDLED_LS_INT (1<<((PCH_UART_HANDLED_LS_INT_SHIFT)<<1))
+
 #define PCH_UART_RBR            0x00
 #define PCH_UART_THR            0x00
 
@@ -229,7 +232,6 @@ struct eg20t_port {
         int start_tx;
         int start_rx;
         int tx_empty;
-        int int_dis_flag;
         int trigger;
         int trigger_level;
         struct pch_uart_buffer rxbuf;
@@ -237,7 +239,6 @@ struct eg20t_port {
         unsigned int fcr;
         unsigned int mcr;
         unsigned int use_dma;
-        unsigned int use_dma_flag;
         struct dma_async_tx_descriptor  *desc_tx;
         struct dma_async_tx_descriptor  *desc_rx;
         struct pch_dma_slave            param_tx;
@@ -560,14 +561,10 @@ static int pch_uart_hal_read(struct eg20t_port *priv, unsigned char *buf,
         return i;
 }
 
-static unsigned int pch_uart_hal_get_iid(struct eg20t_port *priv)
+static unsigned char pch_uart_hal_get_iid(struct eg20t_port *priv)
 {
-        unsigned int iir;
-        int ret;
-
-        iir = ioread8(priv->membase + UART_IIR);
-        ret = (iir & (PCH_UART_IIR_IID | PCH_UART_IIR_TOI | PCH_UART_IIR_IP));
-        return ret;
+        return ioread8(priv->membase + UART_IIR) &\
+                      (PCH_UART_IIR_IID | PCH_UART_IIR_TOI | PCH_UART_IIR_IP);
 }
 
 static u8 pch_uart_hal_get_line_status(struct eg20t_port *priv)
@@ -666,10 +663,13 @@ static void pch_free_dma(struct uart_port *port)
                 dma_release_channel(priv->chan_rx);
                 priv->chan_rx = NULL;
         }
-        if (sg_dma_address(&priv->sg_rx))
-                dma_free_coherent(port->dev, port->fifosize,
-                                  sg_virt(&priv->sg_rx),
-                                  sg_dma_address(&priv->sg_rx));
+
+        if (priv->rx_buf_dma) {
+                dma_free_coherent(port->dev, port->fifosize, priv->rx_buf_virt,
+                                  priv->rx_buf_dma);
+                priv->rx_buf_virt = NULL;
+                priv->rx_buf_dma = 0;
+        }
 
         return;
 }
@@ -1053,12 +1053,17 @@ static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
         unsigned int handled;
         u8 lsr;
         int ret = 0;
-        unsigned int iid;
+        unsigned char iid;
         unsigned long flags;
+        int next = 1;
+        u8 msr;
 
         spin_lock_irqsave(&priv->port.lock, flags);
         handled = 0;
-        while ((iid = pch_uart_hal_get_iid(priv)) > 1) {
+        while (next) {
+                iid = pch_uart_hal_get_iid(priv);
+                if (iid & PCH_UART_IIR_IP) /* No Interrupt */
+                        break;
                 switch (iid) {
                 case PCH_UART_IID_RLS:  /* Receiver Line Status */
                         lsr = pch_uart_hal_get_line_status(priv);
@@ -1066,6 +1071,8 @@ static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
                                                 UART_LSR_PE | UART_LSR_OE)) {
                                 pch_uart_err_ir(priv, lsr);
                                 ret = PCH_UART_HANDLED_RX_ERR_INT;
+                        } else {
+                                ret = PCH_UART_HANDLED_LS_INT;
                         }
                         break;
                 case PCH_UART_IID_RDR:  /* Received Data Ready */
@@ -1092,20 +1099,22 @@ static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
                                 ret = handle_tx(priv);
                         break;
                 case PCH_UART_IID_MS:   /* Modem Status */
-                        ret = PCH_UART_HANDLED_MS_INT;
+                        msr = pch_uart_hal_get_modem(priv);
+                        next = 0; /* MS ir prioirty is the lowest. So, MS ir
+                                     means final interrupt */
+                        if ((msr & UART_MSR_ANY_DELTA) == 0)
+                                break;
+                        ret |= PCH_UART_HANDLED_MS_INT;
                         break;
                 default:        /* Never junp to this label */
-                        dev_err(priv->port.dev, "%s:iid=%d (%lu)\n", __func__,
+                        dev_err(priv->port.dev, "%s:iid=%02x (%lu)\n", __func__,
                                 iid, jiffies);
                         ret = -1;
+                        next = 0;
                         break;
                 }
                 handled |= (unsigned int)ret;
         }
-        if (handled == 0 && iid <= 1) {
-                if (priv->int_dis_flag)
-                        priv->int_dis_flag = 0;
-        }
 
         spin_unlock_irqrestore(&priv->port.lock, flags);
         return IRQ_RETVAL(handled);
@@ -1200,7 +1209,6 @@ static void pch_uart_stop_rx(struct uart_port *port)
         priv = container_of(port, struct eg20t_port, port);
         priv->start_rx = 0;
         pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT);
-        priv->int_dis_flag = 1;
 }
 
 /* Enable the modem status interrupts. */
@@ -1447,7 +1455,6 @@ static int pch_uart_verify_port(struct uart_port *port,
                         __func__);
                 return -EOPNOTSUPP;
 #endif
-                priv->use_dma_flag = 1;
                 dev_info(priv->port.dev, "PCH UART : Use DMA Mode\n");
                 if (!priv->use_dma)
                         pch_request_dma(port);