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, 15 insertions, 13 deletions

diff --git a/linux/include/linux/videodev2.h b/linux/include/linux/videodev2.h
index f02067f7f..29a1c889e 100644
--- a/linux/include/linux/videodev2.h
+++ b/linux/include/linux/videodev2.h
@@ -1337,6 +1337,17 @@ struct v4l2_streamparm
 };
 
 /*
+ *	A D V A N C E D   D E B U G G I N G
+ */
+
+/* VIDIOC_DBG_G_REGISTER and VIDIOC_DBG_S_REGISTER */
+struct v4l2_register {
+	__u32 i2c_id; /* I2C driver ID of the I2C chip, or 0 for the host */
+	__u32 reg;
+	__u32 val;
+};
+
+/*
  *	I O C T L   C O D E S   F O R   V I D E O   D E V I C E S
  *
  */
@@ -1405,6 +1416,9 @@ struct v4l2_streamparm
 #define VIDIOC_ENUM_FRAMESIZES	_IOWR ('V', 74, struct v4l2_frmsizeenum)
 #define VIDIOC_ENUM_FRAMEINTERVALS	_IOWR ('V', 75, struct v4l2_frmivalenum)
 #endif
+/* only implemented if CONFIG_VIDEO_ADV_DEBUG is defined */
+#define	VIDIOC_DBG_S_REGISTER 	_IOW ('d', 100, struct v4l2_register)
+#define	VIDIOC_DBG_G_REGISTER 	_IOWR('d', 101, struct v4l2_register)
 
 #ifdef __OLD_VIDIOC_
 /* for compatibility, will go away some day */
diff --git a/linux/include/media/v4l2-common.h b/linux/include/media/v4l2-common.h
index 6e7500f1d..4d5c3ef64 100644
--- a/linux/include/media/v4l2-common.h
+++ b/linux/include/media/v4l2-common.h
@@ -105,13 +105,6 @@ u32 v4l2_ctrl_next(const u32 * const *ctrl_classes, u32 id);
 
 /* Internal ioctls */
 
-/* VIDIOC_INT_G_REGISTER and VIDIOC_INT_S_REGISTER */
-struct v4l2_register {
-	u32 i2c_id; 		/* I2C driver ID of the I2C chip. 0 for the I2C adapter. */
-	unsigned long reg;
-	u32 val;
-};
-
 /* VIDIOC_INT_DECODE_VBI_LINE */
 struct v4l2_decode_vbi_line {
 	u32 is_second_field;	/* Set to 0 for the first (odd) field,
@@ -181,9 +174,7 @@ enum v4l2_chip_ident {
    Replacement of TUNER_SET_STANDBY. */
 #define VIDIOC_INT_S_STANDBY 	     _IOW('d', 94, u32)
 
-/* only implemented if CONFIG_VIDEO_ADV_DEBUG is defined */
-#define	VIDIOC_INT_S_REGISTER 		_IOW ('d', 100, struct v4l2_register)
-#define	VIDIOC_INT_G_REGISTER 		_IOWR('d', 101, struct v4l2_register)
+/* 100, 101 used by  VIDIOC_DBG_[SG]_REGISTER */
 
 /* Generic reset command. The argument selects which subsystems to reset.
    Passing 0 will always reset the whole chip. */
diff --git a/linux/include/media/v4l2-dev.h b/linux/include/media/v4l2-dev.h
index f42ac241b..1734898b4 100644
--- a/linux/include/media/v4l2-dev.h
+++ b/linux/include/media/v4l2-dev.h
@@ -81,9 +81,6 @@ int v4l_compat_translate_ioctl(struct inode *inode, struct file *file,
 extern long v4l_compat_ioctl32(struct file *file, unsigned int cmd,
 				unsigned long arg);
 
-/* Forward definition of v4l2-common.h defined structure */
-struct v4l2_register;
-
 /*
  * Newer version of video_device, handled by videodev2.c
  * 	This version moves redundant code from video device code to