diff options
author | anish kumar <anish198519851985@gmail.com> | 2012-08-29 15:05:10 -0400 |
---|---|---|
committer | MyungJoo Ham <myungjoo.ham@samsung.com> | 2012-10-21 22:28:10 -0400 |
commit | 28c0ada62d39eaafef03d88a4e6f4c5bcb6e1b6c (patch) | |
tree | 6f4f01eab4ad9c1e59265362a3077a50449cba60 /drivers/extcon/extcon-class.c | |
parent | 0cf6ad8a18f7f7bdbb81975188d9e0656ef277dd (diff) |
extcon: optimising the check_mutually_exclusive function
Rather than re-inventing the wheel we can use the hamming function
to calculate the number of bits set to check for violation of
exclusivity.
Signed-off-by: anish kumar <anish198519851985@gmail.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Diffstat (limited to 'drivers/extcon/extcon-class.c')
-rw-r--r-- | drivers/extcon/extcon-class.c | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/drivers/extcon/extcon-class.c b/drivers/extcon/extcon-class.c index 1e1a3f17a782..1ce76a8d777b 100644 --- a/drivers/extcon/extcon-class.c +++ b/drivers/extcon/extcon-class.c | |||
@@ -89,17 +89,13 @@ static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state) | |||
89 | return 0; | 89 | return 0; |
90 | 90 | ||
91 | for (i = 0; edev->mutually_exclusive[i]; i++) { | 91 | for (i = 0; edev->mutually_exclusive[i]; i++) { |
92 | int count = 0, j; | 92 | int weight; |
93 | u32 correspondants = new_state & edev->mutually_exclusive[i]; | 93 | u32 correspondants = new_state & edev->mutually_exclusive[i]; |
94 | u32 exp = 1; | 94 | |
95 | 95 | /* calculate the total number of bits set */ | |
96 | for (j = 0; j < 32; j++) { | 96 | weight = hweight32(correspondants); |
97 | if (exp & correspondants) | 97 | if (weight > 1) |
98 | count++; | 98 | return i + 1; |
99 | if (count > 1) | ||
100 | return i + 1; | ||
101 | exp <<= 1; | ||
102 | } | ||
103 | } | 99 | } |
104 | 100 | ||
105 | return 0; | 101 | return 0; |