V4L/DVB (11230): hdpvr: return immediately from hdpvr_poll if data is available

simplifies check for available data with hdpvr_get_next_buffer

Signed-off-by: Janne Grunau <j@jannau.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 8 insertions, 12 deletions

diff --git a/drivers/media/video/hdpvr/hdpvr-video.c b/drivers/media/video/hdpvr/hdpvr-video.c
index 9560e19d7cf0..e9078cdedb28 100644
--- a/drivers/media/video/hdpvr/hdpvr-video.c
+++ b/drivers/media/video/hdpvr/hdpvr-video.c
@@ -479,6 +479,7 @@ err:
 
 static unsigned int hdpvr_poll(struct file *filp, poll_table *wait)
 {
+        struct hdpvr_buffer *buf = NULL;
         struct hdpvr_fh *fh = (struct hdpvr_fh *)filp->private_data;
         struct hdpvr_device *dev = fh->dev;
         unsigned int mask = 0;
@@ -499,19 +500,14 @@ static unsigned int hdpvr_poll(struct file *filp, poll_table *wait)
         }
         mutex_unlock(&dev->io_mutex);
 
-        poll_wait(filp, &dev->wait_data, wait);
-
-        mutex_lock(&dev->io_mutex);
-        if (!list_empty(&dev->rec_buff_list)) {
-
-                struct hdpvr_buffer *buf = list_entry(dev->rec_buff_list.next,
-                                                      struct hdpvr_buffer,
-                                                      buff_list);
-
-                if (buf->status == BUFSTAT_READY)
-                        mask |= POLLIN | POLLRDNORM;
+        buf = hdpvr_get_next_buffer(dev);
+        /* only wait if no data is available */
+        if (!buf || buf->status != BUFSTAT_READY) {
+                poll_wait(filp, &dev->wait_data, wait);
+                buf = hdpvr_get_next_buffer(dev);
         }
-        mutex_unlock(&dev->io_mutex);
+        if (buf && buf->status == BUFSTAT_READY)
+                mask |= POLLIN | POLLRDNORM;
 
         return mask;
 }