1 files changed, 36 insertions, 10 deletions

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index fbc5bc022a39..adb0bbcecd24 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -256,6 +256,14 @@ static const char *meson_uart_type(struct uart_port *port)
 	return (port->type == PORT_MESON) ? "meson_uart" : NULL;
 }
 
+/*
+ * This function is called only from probe() using a temporary io mapping
+ * in order to perform a reset before setting up the device. Since the
+ * temporarily mapped region was successfully requested, there can be no
+ * console on this port at this time. Hence it is not necessary for this
+ * function to acquire the port->lock. (Since there is no console on this
+ * port at this time, the port->lock is not initialized yet.)
+ */
 static void meson_uart_reset(struct uart_port *port)
 {
 	u32 val;
@@ -270,9 +278,12 @@ static void meson_uart_reset(struct uart_port *port)
 
 static int meson_uart_startup(struct uart_port *port)
 {
+	unsigned long flags;
 	u32 val;
 	int ret = 0;
 
+	spin_lock_irqsave(&port->lock, flags);
+
 	val = readl(port->membase + AML_UART_CONTROL);
 	val |= AML_UART_CLEAR_ERR;
 	writel(val, port->membase + AML_UART_CONTROL);
@@ -288,6 +299,8 @@ static int meson_uart_startup(struct uart_port *port)
 	val = (AML_UART_RECV_IRQ(1) | AML_UART_XMIT_IRQ(port->fifosize / 2));
 	writel(val, port->membase + AML_UART_MISC);
 
+	spin_unlock_irqrestore(&port->lock, flags);
+
 	ret = request_irq(port->irq, meson_uart_interrupt, 0,
 			  port->name, port);
 
@@ -358,10 +371,14 @@ static void meson_uart_set_termios(struct uart_port *port,
 	else
 		val |= AML_UART_STOP_BIT_1SB;
 
-	if (cflags & CRTSCTS)
-		val &= ~AML_UART_TWO_WIRE_EN;
-	else
+	if (cflags & CRTSCTS) {
+		if (port->flags & UPF_HARD_FLOW)
+			val &= ~AML_UART_TWO_WIRE_EN;
+		else
+			termios->c_cflag &= ~CRTSCTS;
+	} else {
 		val |= AML_UART_TWO_WIRE_EN;
+	}
 
 	writel(val, port->membase + AML_UART_CONTROL);
 
@@ -652,15 +669,19 @@ static int meson_uart_probe_clocks(struct platform_device *pdev,
 
 static int meson_uart_probe(struct platform_device *pdev)
 {
-	struct resource *res_mem, *res_irq;
+	struct resource *res_mem;
 	struct uart_port *port;
+	u32 fifosize = 64; /* Default is 64, 128 for EE UART_0 */
 	int ret = 0;
-	int id = -1;
+	int irq;
+	bool has_rtscts;
 
 	if (pdev->dev.of_node)
 		pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");
 
 	if (pdev->id < 0) {
+		int id;
+
 		for (id = AML_UART_PORT_OFFSET; id < AML_UART_PORT_NUM; id++) {
 			if (!meson_ports[id]) {
 				pdev->id = id;
@@ -676,9 +697,12 @@ static int meson_uart_probe(struct platform_device *pdev)
 	if (!res_mem)
 		return -ENODEV;
 
-	res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!res_irq)
-		return -ENODEV;
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	of_property_read_u32(pdev->dev.of_node, "fifo-size", &fifosize);
+	has_rtscts = of_property_read_bool(pdev->dev.of_node, "uart-has-rtscts");
 
 	if (meson_ports[pdev->id]) {
 		dev_err(&pdev->dev, "port %d already allocated\n", pdev->id);
@@ -701,14 +725,16 @@ static int meson_uart_probe(struct platform_device *pdev)
 	port->iotype = UPIO_MEM;
 	port->mapbase = res_mem->start;
 	port->mapsize = resource_size(res_mem);
-	port->irq = res_irq->start;
+	port->irq = irq;
 	port->flags = UPF_BOOT_AUTOCONF | UPF_LOW_LATENCY;
+	if (has_rtscts)
+		port->flags |= UPF_HARD_FLOW;
 	port->dev = &pdev->dev;
 	port->line = pdev->id;
 	port->type = PORT_MESON;
 	port->x_char = 0;
 	port->ops = &meson_uart_ops;
-	port->fifosize = 64;
+	port->fifosize = fifosize;
 
 	meson_ports[pdev->id] = port;
 	platform_set_drvdata(pdev, port);