1 files changed, 45 insertions, 4 deletions

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 846552bff67d..4e959c43f680 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -47,6 +47,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/err.h>
 #include <linux/irq.h>
+#include <linux/suspend.h>
 
 #include <asm/io.h>
 #include <asm/ioctls.h>
@@ -173,6 +174,12 @@ struct atmel_uart_port {
         bool                    ms_irq_enabled;
         bool                    is_usart;       /* usart or uart */
         struct timer_list       uart_timer;     /* uart timer */
+
+        bool                    suspended;
+        unsigned int            pending;
+        unsigned int            pending_status;
+        spinlock_t              lock_suspended;
+
         int (*prepare_rx)(struct uart_port *port);
         int (*prepare_tx)(struct uart_port *port);
         void (*schedule_rx)(struct uart_port *port);
@@ -1179,12 +1186,15 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
 {
         struct uart_port *port = dev_id;
         struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
-        unsigned int status, pending, pass_counter = 0;
+        unsigned int status, pending, mask, pass_counter = 0;
         bool gpio_handled = false;
 
+        spin_lock(&atmel_port->lock_suspended);
+
         do {
                 status = atmel_get_lines_status(port);
-                pending = status & UART_GET_IMR(port);
+                mask = UART_GET_IMR(port);
+                pending = status & mask;
                 if (!gpio_handled) {
                         /*
                          * Dealing with GPIO interrupt
@@ -1206,11 +1216,21 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
                 if (!pending)
                         break;
 
+                if (atmel_port->suspended) {
+                        atmel_port->pending |= pending;
+                        atmel_port->pending_status = status;
+                        UART_PUT_IDR(port, mask);
+                        pm_system_wakeup();
+                        break;
+                }
+
                 atmel_handle_receive(port, pending);
                 atmel_handle_status(port, pending, status);
                 atmel_handle_transmit(port, pending);
         } while (pass_counter++ < ATMEL_ISR_PASS_LIMIT);
 
+        spin_unlock(&atmel_port->lock_suspended);
+
         return pass_counter ? IRQ_HANDLED : IRQ_NONE;
 }
 
@@ -1742,7 +1762,8 @@ static int atmel_startup(struct uart_port *port)
         /*
          * Allocate the IRQ
          */
-        retval = request_irq(port->irq, atmel_interrupt, IRQF_SHARED,
+        retval = request_irq(port->irq, atmel_interrupt,
+                        IRQF_SHARED | IRQF_COND_SUSPEND,
                         tty ? tty->name : "atmel_serial", port);
         if (retval) {
                 dev_err(port->dev, "atmel_startup - Can't get irq\n");
@@ -2513,8 +2534,14 @@ static int atmel_serial_suspend(struct platform_device *pdev,
 
         /* we can not wake up if we're running on slow clock */
         atmel_port->may_wakeup = device_may_wakeup(&pdev->dev);
-        if (atmel_serial_clk_will_stop())
+        if (atmel_serial_clk_will_stop()) {
+                unsigned long flags;
+
+                spin_lock_irqsave(&atmel_port->lock_suspended, flags);
+                atmel_port->suspended = true;
+                spin_unlock_irqrestore(&atmel_port->lock_suspended, flags);
                 device_set_wakeup_enable(&pdev->dev, 0);
+        }
 
         uart_suspend_port(&atmel_uart, port);
 
@@ -2525,6 +2552,18 @@ static int atmel_serial_resume(struct platform_device *pdev)
 {
         struct uart_port *port = platform_get_drvdata(pdev);
         struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+        unsigned long flags;
+
+        spin_lock_irqsave(&atmel_port->lock_suspended, flags);
+        if (atmel_port->pending) {
+                atmel_handle_receive(port, atmel_port->pending);
+                atmel_handle_status(port, atmel_port->pending,
+                                    atmel_port->pending_status);
+                atmel_handle_transmit(port, atmel_port->pending);
+                atmel_port->pending = 0;
+        }
+        atmel_port->suspended = false;
+        spin_unlock_irqrestore(&atmel_port->lock_suspended, flags);
 
         uart_resume_port(&atmel_uart, port);
         device_set_wakeup_enable(&pdev->dev, atmel_port->may_wakeup);
@@ -2593,6 +2632,8 @@ static int atmel_serial_probe(struct platform_device *pdev)
         port->backup_imr = 0;
         port->uart.line = ret;
 
+        spin_lock_init(&port->lock_suspended);
+
         ret = atmel_init_gpios(port, &pdev->dev);
         if (ret < 0)
                 dev_err(&pdev->dev, "%s",