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>

1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/media/video/v4l2-common.c b/drivers/media/video/v4l2-common.c
index ddfd80c5618b..3506cb667111 100644
--- a/drivers/media/video/v4l2-common.c
+++ b/drivers/media/video/v4l2-common.c
@@ -51,6 +51,7 @@
 #include <linux/mm.h>
 #include <linux/string.h>
 #include <linux/errno.h>
+#include <linux/i2c.h>
 #include <asm/uaccess.h>
 #include <asm/system.h>
 #include <asm/pgtable.h>
@@ -947,6 +948,32 @@ u32 v4l2_ctrl_next(const u32 * const * ctrl_classes, u32 id)
         return **ctrl_classes;
 }
 
+int v4l2_chip_match_i2c_client(struct i2c_client *c, u32 match_type, u32 match_chip)
+{
+        switch (match_type) {
+        case V4L2_CHIP_MATCH_ALWAYS:
+                return 1;
+        case V4L2_CHIP_MATCH_I2C_DRIVER:
+                return (c != NULL && c->driver != NULL && c->driver->id == match_chip);
+        case V4L2_CHIP_MATCH_I2C_ADDR:
+                return (c != NULL && c->addr == match_chip);
+        default:
+                return 0;
+        }
+}
+
+int v4l2_chip_match_host(u32 match_type, u32 match_chip)
+{
+        switch (match_type) {
+        case V4L2_CHIP_MATCH_ALWAYS:
+                return 1;
+        case V4L2_CHIP_MATCH_HOST:
+                return match_chip == 0;
+        default:
+                return 0;
+        }
+}
+
 /* ----------------------------------------------------------------- */
 
 EXPORT_SYMBOL(v4l2_norm_to_name);
@@ -970,6 +997,9 @@ EXPORT_SYMBOL(v4l2_ctrl_query_menu);
 EXPORT_SYMBOL(v4l2_ctrl_query_fill);
 EXPORT_SYMBOL(v4l2_ctrl_query_fill_std);
 
+EXPORT_SYMBOL(v4l2_chip_match_i2c_client);
+EXPORT_SYMBOL(v4l2_chip_match_host);
+
 /*
  * Local variables:
  * c-basic-offset: 8