ipack/devices/ipoctal: Fix race condition during Tx
authorAlberto Garcia <agarcia@igalia.com>
Mon, 10 Dec 2012 10:49:57 +0000 (11:49 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 16 Jan 2013 02:24:37 +0000 (18:24 -0800)
In order to transmit data, the driver enables Tx and sleeps until
*board_write is set to 1 by the interrupt handler.

It can happen, though, that the data is sent even before the process
is asleep. In this case *board_write must be set to 1 anyway,
otherwise we will be waiting for a condition that will never be true.

Signed-off-by: Alberto Garcia <agarcia@igalia.com>
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/ipack/devices/ipoctal.c

index 576d53d..e66135d 100644 (file)
@@ -195,13 +195,10 @@ static void ipoctal_irq_tx(struct ipoctal_channel *channel)
        *pointer_write = *pointer_write % PAGE_SIZE;
        channel->nb_bytes--;
 
-       if ((channel->nb_bytes == 0) &&
-           (waitqueue_active(&channel->queue))) {
-
-               if (channel->board_id != IPACK1_DEVICE_ID_SBS_OCTAL_485) {
-                       *channel->board_write = 1;
-                       wake_up_interruptible(&channel->queue);
-               }
+       if (channel->nb_bytes == 0 &&
+           channel->board_id != IPACK1_DEVICE_ID_SBS_OCTAL_485) {
+               *channel->board_write = 1;
+               wake_up_interruptible(&channel->queue);
        }
 }