Make VIDIOC_INT_[SG]_REGISTER ioctls no longer internal only

From: Trent Piepho <xyzzy@speakeasy.org>

The direct register access ioctls were defined as kernel internal only,
but they are very useful for debugging hardware from userspace and are
used as such.  Officially export them.

VIDIOC_INT_[SG]_REGISTER is renamed to VIDIOC_DBG_[SG]_REGISTER

Definition of ioctl and struct v4l2_register is moved from v4l2-common.h
to videodev2.h.

Types used in struct v4l2_register are changed to the userspace
exportable versions (u32 -> __u32, etc).

Use of VIDIOC_DBG_S_REGISTER requires CAP_SYS_ADMIN permission, so move
the check into the video_ioctl2() dispatcher so it doesn't need to be
duplicated in each driver's call-back function.

CAP_SYS_ADMIN check is added to pvrusb2 (which doesn't use video_ioctl2).

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>

3 files changed, 13 insertions, 9 deletions

diff --git a/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.c b/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.c
index b07bd58ea..3b2d2f6ff 100644
--- a/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.c
+++ b/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.c
@@ -3390,7 +3390,7 @@ static int pvr2_hdw_get_eeprom_addr(struct pvr2_hdw *hdw)
 
 
 int pvr2_hdw_register_access(struct pvr2_hdw *hdw,
-			     u32 chip_id,unsigned long reg_id,
+			     u32 chip_id, u32 reg_id,
 			     int setFl,u32 *val_ptr)
 {
 #ifdef CONFIG_VIDEO_ADV_DEBUG
@@ -3408,8 +3408,8 @@ int pvr2_hdw_register_access(struct pvr2_hdw *hdw,
 			cp = list_entry(item,struct pvr2_i2c_client,list);
 			if (cp->client->driver->id != chip_id) continue;
 			stat = pvr2_i2c_client_cmd(
-				cp,(setFl ? VIDIOC_INT_S_REGISTER :
-				    VIDIOC_INT_G_REGISTER),&req);
+				cp,(setFl ? VIDIOC_DBG_S_REGISTER :
+				    VIDIOC_DBG_G_REGISTER),&req);
 			if (!setFl) *val_ptr = req.val;
 			okFl = !0;
 			break;
diff --git a/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.h b/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.h
index ab99bea88..9785ffcce 100644
--- a/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.h
+++ b/linux/drivers/media/video/pvrusb2/pvrusb2-hdw.h
@@ -231,7 +231,7 @@ void pvr2_hdw_v4l_store_minor_number(struct pvr2_hdw *,
    setFl   - true to set the register, false to read it
    val_ptr - storage location for source / result. */
 int pvr2_hdw_register_access(struct pvr2_hdw *,
-			     u32 chip_id,unsigned long reg_id,
+			     u32 chip_id,u32 reg_id,
 			     int setFl,u32 *val_ptr);
 
 /* The following entry points are all lower level things you normally don't
diff --git a/linux/drivers/media/video/pvrusb2/pvrusb2-v4l2.c b/linux/drivers/media/video/pvrusb2/pvrusb2-v4l2.c
index 621a0dd31..e692ad5f7 100644
--- a/linux/drivers/media/video/pvrusb2/pvrusb2-v4l2.c
+++ b/linux/drivers/media/video/pvrusb2/pvrusb2-v4l2.c
@@ -739,16 +739,20 @@ static int pvr2_v4l2_do_ioctl(struct inode *inode, struct file *file,
 		break;
 	}
 #ifdef CONFIG_VIDEO_ADV_DEBUG
-	case VIDIOC_INT_G_REGISTER:
-	case VIDIOC_INT_S_REGISTER:
+	case VIDIOC_DBG_S_REGISTER:
+		if (!capable(CAP_SYS_ADMIN)) {
+			ret = -EPERM;
+			break;
+		} /* fall through */
+	case VIDIOC_DBG_G_REGISTER:
 	{
 		u32 val;
 		struct v4l2_register *req = (struct v4l2_register *)arg;
-		if (cmd == VIDIOC_INT_S_REGISTER) val = req->val;
+		if (cmd == VIDIOC_DBG_S_REGISTER) val = req->val;
 		ret = pvr2_hdw_register_access(
 			hdw,req->i2c_id,req->reg,
-			cmd == VIDIOC_INT_S_REGISTER,&val);
-		if (cmd == VIDIOC_INT_G_REGISTER) req->val = val;
+			cmd == VIDIOC_DBG_S_REGISTER,&val);
+		if (cmd == VIDIOC_DBG_G_REGISTER) req->val = val;
 		break;
 	}
 #endif