1 files changed, 30 insertions, 22 deletions

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 41b8c6b27136..3f33014022f0 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -157,7 +157,11 @@ static u32 uart_read(struct uart_8250_port *up, u32 reg)
 	return readl(up->port.membase + (reg << up->port.regshift));
 }
 
-static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
+/*
+ * Called on runtime PM resume path from omap8250_restore_regs(), and
+ * omap8250_set_mctrl().
+ */
+static void __omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
 	struct uart_8250_port *up = up_to_u8250p(port);
 	struct omap8250_priv *priv = up->port.private_data;
@@ -181,6 +185,20 @@ static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	}
 }
 
+static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	int err;
+
+	err = pm_runtime_resume_and_get(port->dev);
+	if (err)
+		return;
+
+	__omap8250_set_mctrl(port, mctrl);
+
+	pm_runtime_mark_last_busy(port->dev);
+	pm_runtime_put_autosuspend(port->dev);
+}
+
 /*
  * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
  * The access to uart register after MDR1 Access
@@ -193,27 +211,10 @@ static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
 static void omap_8250_mdr1_errataset(struct uart_8250_port *up,
 				     struct omap8250_priv *priv)
 {
-	u8 timeout = 255;
-
 	serial_out(up, UART_OMAP_MDR1, priv->mdr1);
 	udelay(2);
 	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
 			UART_FCR_CLEAR_RCVR);
-	/*
-	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
-	 * TX_FIFO_E bit is 1.
-	 */
-	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
-				(UART_LSR_THRE | UART_LSR_DR))) {
-		timeout--;
-		if (!timeout) {
-			/* Should *never* happen. we warn and carry on */
-			dev_crit(up->port.dev, "Errata i202: timedout %x\n",
-				 serial_in(up, UART_LSR));
-			break;
-		}
-		udelay(1);
-	}
 }
 
 static void omap_8250_get_divisor(struct uart_port *port, unsigned int baud,
@@ -292,6 +293,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
 {
 	struct omap8250_priv *priv = up->port.private_data;
 	struct uart_8250_dma	*dma = up->dma;
+	u8 mcr = serial8250_in_MCR(up);
 
 	if (dma && dma->tx_running) {
 		/*
@@ -308,7 +310,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
 	serial_out(up, UART_EFR, UART_EFR_ECB);
 
 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
-	serial8250_out_MCR(up, UART_MCR_TCRTLR);
+	serial8250_out_MCR(up, mcr | UART_MCR_TCRTLR);
 	serial_out(up, UART_FCR, up->fcr);
 
 	omap8250_update_scr(up, priv);
@@ -324,7 +326,8 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
 	serial_out(up, UART_LCR, 0);
 
 	/* drop TCR + TLR access, we setup XON/XOFF later */
-	serial8250_out_MCR(up, up->mcr);
+	serial8250_out_MCR(up, mcr);
+
 	serial_out(up, UART_IER, up->ier);
 
 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
@@ -341,7 +344,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
 
 	omap8250_update_mdr1(up, priv);
 
-	up->port.ops->set_mctrl(&up->port, up->port.mctrl);
+	__omap8250_set_mctrl(&up->port, up->port.mctrl);
 
 	if (up->port.rs485.flags & SER_RS485_ENABLED)
 		serial8250_em485_stop_tx(up);
@@ -669,7 +672,6 @@ static int omap_8250_startup(struct uart_port *port)
 
 	pm_runtime_get_sync(port->dev);
 
-	up->mcr = 0;
 	serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
 
 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
@@ -1458,9 +1460,15 @@ err:
 static int omap8250_remove(struct platform_device *pdev)
 {
 	struct omap8250_priv *priv = platform_get_drvdata(pdev);
+	int err;
+
+	err = pm_runtime_resume_and_get(&pdev->dev);
+	if (err)
+		return err;
 
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_put_sync(&pdev->dev);
+	flush_work(&priv->qos_work);
 	pm_runtime_disable(&pdev->dev);
 	serial8250_unregister_port(priv->line);
 	cpu_latency_qos_remove_request(&priv->pm_qos_request);