Merge tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull TTY updates from Greg Kroah-Hartman:
 "Here's the big TTY/serial driver pull request for the 3.5-rc1 merge
  window.

  Nothing major in here, just lots of incremental changes from Alan and
  Jiri reworking some tty core things to behave better and to get a more
  solid grasp on some of the nasty tty locking issues.

  There are a few tty and serial driver updates in here as well.

  All of this has been in the linux-next releases for a while with no
  problems.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (115 commits)
  serial: bfin_uart: Make MMR access compatible with 32 bits bf609 style controller.
  serial: bfin_uart: RTS and CTS MMRs can be either 16-bit width or 32-bit width.
  serial: bfin_uart: narrow the reboot condition in DMA tx interrupt
  serial: bfin_uart: Adapt bf5xx serial driver to bf60x serial4 controller.
  Revert "serial_core: Update buffer overrun statistics."
  tty: hvc_xen: NULL dereference on allocation failure
  tty: Fix LED error return
  tty: Allow uart_register/unregister/register
  tty: move global ldisc idle waitqueue to the individual ldisc
  serial8250-em: Add DT support
  serial8250-em: clk_get() IS_ERR() error handling fix
  serial_core: Update buffer overrun statistics.
  tty: drop the pty lock during hangup
  cris: fix missing tty arg in wait_event_interruptible_tty call
  tty/amiserial: Add missing argument for tty_unlock()
  tty_lock: Localise the lock
  pty: Lock the devpts bits privately
  tty_lock: undo the old tty_lock use on the ctty
  serial8250-em: Emma Mobile UART driver V2
  Add missing call to uart_update_timeout()
  ...

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);