V4L/DVB (5304): Improve chip matching in v4l2_register

The chip matching in struct v4l2_register for VIDIOC_DBG_G/S_REGISTER 
was rather primitive. It could not be extended to other busses besides 
i2c and it lacked a way to.

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

2 files changed, 17 insertions, 2 deletions

diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index 65a165f918c9..e3ab047f90ef 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -1306,10 +1306,17 @@ struct v4l2_streamparm
  */
 
 /* VIDIOC_DBG_G_REGISTER and VIDIOC_DBG_S_REGISTER */
+
+#define V4L2_CHIP_MATCH_ALWAYS     0  /* Match always (match_chip is not used) */
+#define V4L2_CHIP_MATCH_HOST       1  /* Match against chip ID on host (0 for the host) */
+#define V4L2_CHIP_MATCH_I2C_DRIVER 2  /* Match against I2C driver ID */
+#define V4L2_CHIP_MATCH_I2C_ADDR   3  /* Match against I2C 7-bit address */
+
 struct v4l2_register {
+        __u32 match_type; /* Match type */
+        __u32 match_chip; /* Match this chip, meaning determined by match_type */
         __u64 reg;
-        __u32 i2c_id; /* I2C driver ID of the I2C chip, or 0 for the host */
-        __u32 val;
+        __u64 val;
 };
 
 /*
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index 244e440edb53..6eaeec98ed89 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -94,6 +94,14 @@ u32 v4l2_ctrl_next(const u32 * const *ctrl_classes, u32 id);
 
 /* ------------------------------------------------------------------------- */
 
+/* Register/chip ident helper function */
+
+struct i2c_client; /* forward reference */
+int v4l2_chip_match_i2c_client(struct i2c_client *c, u32 id_type, u32 chip_id);
+int v4l2_chip_match_host(u32 id_type, u32 chip_id);
+
+/* ------------------------------------------------------------------------- */
+
 /* Internal ioctls */
 
 /* VIDIOC_INT_DECODE_VBI_LINE */