V4L/DVB (8506): empress: fix control handling oops

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 28 insertions, 12 deletions

diff --git a/drivers/media/video/saa7134/saa7134-video.c b/drivers/media/video/saa7134/saa7134-video.c
index 5e9cfc891be8..eb824897416b 100644
--- a/drivers/media/video/saa7134/saa7134-video.c
+++ b/drivers/media/video/saa7134/saa7134-video.c
@@ -1112,10 +1112,8 @@ static struct videobuf_queue_ops video_qops = {
 
 /* ------------------------------------------------------------------ */
 
-int saa7134_g_ctrl(struct file *file, void *priv, struct v4l2_control *c)
+int saa7134_g_ctrl_internal(struct saa7134_dev *dev, struct saa7134_fh *fh, struct v4l2_control *c)
 {
-        struct saa7134_fh *fh = priv;
-        struct saa7134_dev *dev = fh->dev;
         const struct v4l2_queryctrl* ctrl;
 
         ctrl = ctrl_by_id(c->id);
@@ -1160,20 +1158,31 @@ int saa7134_g_ctrl(struct file *file, void *priv, struct v4l2_control *c)
         }
         return 0;
 }
-EXPORT_SYMBOL_GPL(saa7134_g_ctrl);
+EXPORT_SYMBOL_GPL(saa7134_g_ctrl_internal);
+
+static int saa7134_g_ctrl(struct file *file, void *priv, struct v4l2_control *c)
+{
+        struct saa7134_fh *fh = priv;
+
+        return saa7134_g_ctrl_internal(fh->dev, fh, c);
+}
 
-int saa7134_s_ctrl(struct file *file, void *f, struct v4l2_control *c)
+int saa7134_s_ctrl_internal(struct saa7134_dev *dev,  struct saa7134_fh *fh, struct v4l2_control *c)
 {
         const struct v4l2_queryctrl* ctrl;
-        struct saa7134_fh *fh = f;
-        struct saa7134_dev *dev = fh->dev;
         unsigned long flags;
         int restart_overlay = 0;
-        int err = -EINVAL;
+        int err;
 
-        err = v4l2_prio_check(&dev->prio, &fh->prio);
-        if (0 != err)
-                return err;
+        /* When called from the empress code fh == NULL.
+           That needs to be fixed somehow, but for now this is
+           good enough. */
+        if (fh) {
+                err = v4l2_prio_check(&dev->prio, &fh->prio);
+                if (0 != err)
+                        return err;
+        }
+        err = -EINVAL;
 
         mutex_lock(&dev->lock);
 
@@ -1274,7 +1283,14 @@ error:
         mutex_unlock(&dev->lock);
         return err;
 }
-EXPORT_SYMBOL_GPL(saa7134_s_ctrl);
+EXPORT_SYMBOL_GPL(saa7134_s_ctrl_internal);
+
+static int saa7134_s_ctrl(struct file *file, void *f, struct v4l2_control *c)
+{
+        struct saa7134_fh *fh = f;
+
+        return saa7134_s_ctrl_internal(fh->dev, fh, c);
+}
 
 /* ------------------------------------------------------------------ */