Merge branch 'mullins' of git://people.freedesktop.org/~deathsimple/linux into drm...

[cascardo/linux.git] / drivers / tty / serial / mrst_max3110.c

diff --git a/drivers/tty/serial/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c
index a67e708..db0448a 100644 (file)
--- a/drivers/tty/serial/mrst_max3110.c
+++ b/drivers/tty/serial/mrst_max3110.c
@@ -43,6 +43,7 @@
 
 #include <linux/kthread.h>
 #include <linux/spi/spi.h>
+#include <linux/pm.h>
 
 #include "mrst_max3110.h"
 
@@ -61,6 +62,7 @@ struct uart_max3110 {
        struct task_struct *main_thread;
        struct task_struct *read_thread;
        struct mutex thread_mutex;
+       struct mutex io_mutex;
 
        u32 baud;
        u16 cur_conf;
@@ -90,6 +92,7 @@ static int max3110_write_then_read(struct uart_max3110 *max,
        struct spi_transfer     x;
        int ret;
 
+       mutex_lock(&max->io_mutex);
        spi_message_init(&message);
        memset(&x, 0, sizeof x);
        x.len = len;
@@ -104,6 +107,7 @@ static int max3110_write_then_read(struct uart_max3110 *max,
 
        /* Do the i/o */
        ret = spi_sync(spi, &message);
+       mutex_unlock(&max->io_mutex);
        return ret;
 }
 
@@ -491,19 +495,9 @@ static int serial_m3110_startup(struct uart_port *port)
        port->state->port.low_latency = 1;
 
        if (max->irq) {
-               max->read_thread = NULL;
-               ret = request_irq(max->irq, serial_m3110_irq,
-                               IRQ_TYPE_EDGE_FALLING, "max3110", max);
-               if (ret) {
-                       max->irq = 0;
-                       pr_err(PR_FMT "unable to allocate IRQ, polling\n");
-               }  else {
-                       /* Enable RX IRQ only */
-                       config |= WC_RXA_IRQ_ENABLE;
-               }
-       }
-
-       if (max->irq == 0) {
+               /* Enable RX IRQ only */
+               config |= WC_RXA_IRQ_ENABLE;
+       } else {
                /* If IRQ is disabled, start a read thread for input data */
                max->read_thread =
                        kthread_run(max3110_read_thread, max, "max3110_read");
@@ -517,8 +511,6 @@ static int serial_m3110_startup(struct uart_port *port)
 
        ret = max3110_out(max, config);
        if (ret) {
-               if (max->irq)
-                       free_irq(max->irq, max);
                if (max->read_thread)
                        kthread_stop(max->read_thread);
                max->read_thread = NULL;
@@ -540,9 +532,6 @@ static void serial_m3110_shutdown(struct uart_port *port)
                max->read_thread = NULL;
        }
 
-       if (max->irq)
-               free_irq(max->irq, max);
-
        /* Disable interrupts from this port */
        config = WC_TAG | WC_SW_SHDI;
        max3110_out(max, config);
@@ -749,7 +738,8 @@ static int serial_m3110_suspend(struct device *dev)
        struct spi_device *spi = to_spi_device(dev);
        struct uart_max3110 *max = spi_get_drvdata(spi);
 
-       disable_irq(max->irq);
+       if (max->irq > 0)
+               disable_irq(max->irq);
        uart_suspend_port(&serial_m3110_reg, &max->port);
        max3110_out(max, max->cur_conf | WC_SW_SHDI);
        return 0;
@@ -762,7 +752,8 @@ static int serial_m3110_resume(struct device *dev)
 
        max3110_out(max, max->cur_conf);
        uart_resume_port(&serial_m3110_reg, &max->port);
-       enable_irq(max->irq);
+       if (max->irq > 0)
+               enable_irq(max->irq);
        return 0;
 }
 
@@ -803,6 +794,7 @@ static int serial_m3110_probe(struct spi_device *spi)
        max->irq = (u16)spi->irq;
 
        mutex_init(&max->thread_mutex);
+       mutex_init(&max->io_mutex);
 
        max->word_7bits = 0;
        max->parity = 0;
@@ -840,6 +832,16 @@ static int serial_m3110_probe(struct spi_device *spi)
                goto err_kthread;
        }
 
+       if (max->irq) {
+               ret = request_irq(max->irq, serial_m3110_irq,
+                               IRQ_TYPE_EDGE_FALLING, "max3110", max);
+               if (ret) {
+                       max->irq = 0;
+                       dev_warn(&spi->dev,
+                       "unable to allocate IRQ, will use polling method\n");
+               }
+       }
+
        spi_set_drvdata(spi, max);
        pmax = max;
 
@@ -867,6 +869,9 @@ static int serial_m3110_remove(struct spi_device *dev)
 
        free_page((unsigned long)max->con_xmit.buf);
 
+       if (max->irq)
+               free_irq(max->irq, max);
+
        if (max->main_thread)
                kthread_stop(max->main_thread);