One final thing:

On Tue, Jul 13, 2021 at 07:45:21PM -0700, longli@linuxonhyperv.com wrote:

+#define az_blob_dbg(fmt, args...) dev_dbg(&az_blob_dev.device->device, fmt, ##args)
+#define az_blob_info(fmt, args...) dev_info(&az_blob_dev.device->device, fmt, ##args)
+#define az_blob_warn(fmt, args...) dev_warn(&az_blob_dev.device->device, fmt, ##args)
+#define az_blob_err(fmt, args...) dev_err(&az_blob_dev.device->device, fmt, ##args)

This tiny driver does not deserve a different loging scheme from all of
the rest of the kernel.  Just use the dev_* calls directly please, no
need to try to roll your own.  Especially for a 600 line file.

And remove your calls to az_blob_info() that are just debugging stuff,
when the driver is working properly, it is quiet.

thanks,

greg k-h