X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=drivers%2Fstaging%2Fcomedi%2Fcomedi_fops.c;h=a023f522408d486efb163412632e8ff6ac68a0fd;hp=13e79a1110fa5d1c8671bbc29d21e7f58838a886;hb=1ff13c78ca3975a94460a6a0b49acf9a787ed350;hpb=35ad1797ad99b8e73758c805803021cbda799dcb;ds=sidebyside

diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index 13e79a1110fa..a023f522408d 100644
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -1574,7 +1574,7 @@ static unsigned int comedi_poll(struct file *file, poll_table * wait)
 
 	mask = 0;
 	read_subdev = comedi_get_read_subdevice(dev_file_info);
-	if (read_subdev) {
+	if (read_subdev && read_subdev->async) {
 		poll_wait(file, &read_subdev->async->wait_head, wait);
 		if (!read_subdev->busy
 		    || comedi_buf_read_n_available(read_subdev->async) > 0
@@ -1584,7 +1584,7 @@ static unsigned int comedi_poll(struct file *file, poll_table * wait)
 		}
 	}
 	write_subdev = comedi_get_write_subdevice(dev_file_info);
-	if (write_subdev) {
+	if (write_subdev && write_subdev->async) {
 		poll_wait(file, &write_subdev->async->wait_head, wait);
 		comedi_buf_write_alloc(write_subdev->async,
 				       write_subdev->async->prealloc_bufsz);
@@ -1626,7 +1626,7 @@ static ssize_t comedi_write(struct file *file, const char __user *buf,
 	}
 
 	s = comedi_get_write_subdevice(dev_file_info);
-	if (s == NULL) {
+	if (s == NULL || s->async == NULL) {
 		retval = -EIO;
 		goto done;
 	}
@@ -1737,7 +1737,7 @@ static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes,
 	}
 
 	s = comedi_get_read_subdevice(dev_file_info);
-	if (s == NULL) {
+	if (s == NULL || s->async == NULL) {
 		retval = -EIO;
 		goto done;
 	}