V4L/DVB (10237): pvrusb2: Generate a device-unique identifier

Implement a new internal function to create a string device
identifier.  This ID stays with the specific device, making it useful
to user space to identify specific devices.  We use the serial number
if available; otherwise we give up and just spit out a unit/instance ID.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-hdw-internal.h b/drivers/media/video/pvrusb2/pvrusb2-hdw-internal.h
index de7ee7264be6..d96f0f51076e 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-hdw-internal.h
+++ b/drivers/media/video/pvrusb2/pvrusb2-hdw-internal.h
@@ -195,8 +195,20 @@ struct pvr2_hdw {
         struct mutex big_lock_mutex;
         int big_lock_held;  /* For debugging */
 
+        /* This is a simple string which identifies the instance of this
+           driver.  It is unique within the set of existing devices, but
+           there is no attempt to keep the name consistent with the same
+           physical device each time. */
         char name[32];
 
+        /* This is a simple string which identifies the physical device
+           instance itself - if possible.  (If not possible, then it is
+           based on the specific driver instance, similar to name above.)
+           The idea here is that userspace might hopefully be able to use
+           this recognize specific tuners.  It will encode a serial number,
+           if available. */
+        char identifier[32];
+
         /* I2C stuff */
         struct i2c_adapter i2c_adap;
         struct i2c_algorithm i2c_algo;