How to check diskgroup usage

Query:

Only for External Redundancy: 

set lines 200 pages 200
SELECT
   GROUP_NUMBER Group_Num
  ,name                                     group_name
  , state                                    state
  , type                                     type
  , total_mb                                 total_mb
  , (total_mb - free_mb)                     used_mb
  , free_mb
  , ROUND((1- (free_mb / total_mb))*100, 2)  pct_used FROM
    v$asm_diskgroup
where total_mb > 0
ORDER BY GROUP_NUMBER;

For External, Normal and High Redundancy:

select
GROUP_NUMBER Group_Num,
name,
round (total_mb/1024,2) TOTAL_GB,
 round (USABLE_FILE_MB/1024,2) FREE_GB,
round(USABLE_FILE_MB/total_mb*100,2) PER_FREE
from v$asm_diskgroup
ORDER BY GROUP_NUMBER;