1 files changed, 18 insertions, 28 deletions

diff --git a/drivers/serial/mrst_max3110.c b/drivers/serial/mrst_max3110.c
index 0341853e0c28..f6ad1ecbff79 100644
--- a/drivers/serial/mrst_max3110.c
+++ b/drivers/serial/mrst_max3110.c
@@ -48,6 +48,10 @@
 
 #define PR_FMT  "mrst_max3110: "
 
+#define UART_TX_NEEDED 1
+#define CON_TX_NEEDED  2
+#define BIT_IRQ_PENDING    3
+
 struct uart_max3110 {
         struct uart_port port;
         struct spi_device *spi;
@@ -63,15 +67,13 @@ struct uart_max3110 {
         u8 clock;
         u8 parity, word_7bits;
 
-        atomic_t uart_tx_need;
+        unsigned long uart_flags;
 
         /* console related */
         struct circ_buf con_xmit;
-        atomic_t con_tx_need;
 
         /* irq related */
         u16 irq;
-        atomic_t irq_pending;
 };
 
 /* global data structure, may need be removed */
@@ -176,10 +178,9 @@ static void serial_m3110_con_putchar(struct uart_port *port, int ch)
                 xmit->head = (xmit->head + 1) & (PAGE_SIZE - 1);
         }
 
-        if (!atomic_read(&max->con_tx_need)) {
-                atomic_set(&max->con_tx_need, 1);
+
+        if (!test_and_set_bit(CON_TX_NEEDED, &max->uart_flags))
                 wake_up_process(max->main_thread);
-        }
 }
 
 /*
@@ -318,10 +319,8 @@ static void serial_m3110_start_tx(struct uart_port *port)
         struct uart_max3110 *max =
                 container_of(port, struct uart_max3110, port);
 
-        if (!atomic_read(&max->uart_tx_need)) {
-                atomic_set(&max->uart_tx_need, 1);
+        if (!test_and_set_bit(UART_TX_NEEDED, &max->uart_flags))
                 wake_up_process(max->main_thread);
-        }
 }
 
 static void receive_chars(struct uart_max3110 *max, unsigned char *str, int len)
@@ -392,32 +391,23 @@ static int max3110_main_thread(void *_max)
         pr_info(PR_FMT "start main thread\n");
 
         do {
-                wait_event_interruptible(*wq, (atomic_read(&max->irq_pending) ||
-                                               atomic_read(&max->con_tx_need) ||
-                                             atomic_read(&max->uart_tx_need)) ||
-                                             kthread_should_stop());
+                wait_event_interruptible(*wq, max->uart_flags || kthread_should_stop());
 
                 mutex_lock(&max->thread_mutex);
 
-#ifdef CONFIG_MRST_MAX3110_IRQ
-                if (atomic_read(&max->irq_pending)) {
+                if (test_and_clear_bit(BIT_IRQ_PENDING, &max->uart_flags))
                         max3110_console_receive(max);
-                        atomic_set(&max->irq_pending, 0);
-                }
-#endif
 
                 /* first handle console output */
-                if (atomic_read(&max->con_tx_need)) {
+                if (test_and_clear_bit(CON_TX_NEEDED, &max->uart_flags))
                         send_circ_buf(max, xmit);
-                        atomic_set(&max->con_tx_need, 0);
-                }
 
                 /* handle uart output */
-                if (atomic_read(&max->uart_tx_need)) {
+                if (test_and_clear_bit(UART_TX_NEEDED, &max->uart_flags))
                         transmit_char(max);
-                        atomic_set(&max->uart_tx_need, 0);
-                }
+
                 mutex_unlock(&max->thread_mutex);
+
         } while (!kthread_should_stop());
 
         return ret;
@@ -430,10 +420,9 @@ static irqreturn_t serial_m3110_irq(int irq, void *dev_id)
 
         /* max3110's irq is a falling edge, not level triggered,
          * so no need to disable the irq */
-        if (!atomic_read(&max->irq_pending)) {
-                atomic_inc(&max->irq_pending);
+        if (!test_and_set_bit(BIT_IRQ_PENDING, &max->uart_flags))
                 wake_up_process(max->main_thread);
-        }
+
         return IRQ_HANDLED;
 }
 #else
@@ -753,7 +742,8 @@ static int serial_m3110_probe(struct spi_device *spi)
         max->baud = 0;
 
         max->cur_conf = 0;
-        atomic_set(&max->irq_pending, 0);
+        max->uart_flags = 0;
+
         /* Check if reading configuration register returns something sane */
 
         res = RC_TAG;