V4L/DVB (13344): soc-camera: properly initialise the device object when reusing

Commit ef373189f62413803b7b816c972fc154c488cdc0 "fix use-after-free Oops,
resulting from a driver-core API change" fixed the Oops, but didn't correct
missing device object initialisation. This patch makes unloading and reloading
of soc-camera host- and client-drivers possible again.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 12 insertions, 5 deletions

diff --git a/drivers/media/video/soc_camera.c b/drivers/media/video/soc_camera.c
index 36e617bd13c7..95fdeb23c2c1 100644
--- a/drivers/media/video/soc_camera.c
+++ b/drivers/media/video/soc_camera.c
@@ -1097,6 +1097,13 @@ static int default_s_crop(struct soc_camera_device *icd, struct v4l2_crop *a)
         return v4l2_subdev_call(sd, video, s_crop, a);
 }
 
+static void soc_camera_device_init(struct device *dev, void *pdata)
+{
+        dev->platform_data      = pdata;
+        dev->bus                = &soc_camera_bus_type;
+        dev->release            = dummy_release;
+}
+
 int soc_camera_host_register(struct soc_camera_host *ici)
 {
         struct soc_camera_host *ix;
@@ -1158,6 +1165,7 @@ void soc_camera_host_unregister(struct soc_camera_host *ici)
 
         list_for_each_entry(icd, &devices, list) {
                 if (icd->iface == ici->nr) {
+                        void *pdata = icd->dev.platform_data;
                         /* The bus->remove will be called */
                         device_unregister(&icd->dev);
                         /*
@@ -1169,6 +1177,7 @@ void soc_camera_host_unregister(struct soc_camera_host *ici)
                          * device private data.
                          */
                         memset(&icd->dev, 0, sizeof(icd->dev));
+                        soc_camera_device_init(&icd->dev, pdata);
                 }
         }
 
@@ -1200,10 +1209,7 @@ static int soc_camera_device_register(struct soc_camera_device *icd)
                  * man, stay reasonable... */
                 return -ENOMEM;
 
-        icd->devnum = num;
-        icd->dev.bus = &soc_camera_bus_type;
-
-        icd->dev.release        = dummy_release;
+        icd->devnum             = num;
         icd->use_count          = 0;
         icd->host_priv          = NULL;
         mutex_init(&icd->video_lock);
@@ -1311,12 +1317,13 @@ static int __devinit soc_camera_pdrv_probe(struct platform_device *pdev)
         icd->iface = icl->bus_id;
         icd->pdev = &pdev->dev;
         platform_set_drvdata(pdev, icd);
-        icd->dev.platform_data = icl;
 
         ret = soc_camera_device_register(icd);
         if (ret < 0)
                 goto escdevreg;
 
+        soc_camera_device_init(&icd->dev, icl);
+
         icd->user_width         = DEFAULT_WIDTH;
         icd->user_height        = DEFAULT_HEIGHT;