asgardius/android_kernel_motorola_sm6225
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iwlwifi: mvm: fix first_antenna

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first_antenna is supposed to return the first antenna as a
0-based bitmap: ANT_A is BIT(0), ANT_B is BIT(1), etc...
Since ffs is 1 based (ffs(BIT(0)) = 1), then we had an
off-by-one bug:
BIT(ffs(ANT_A)) = BIT(ffs(BIT(0))) = BIT(1) = ANT_B.
So what we really want is:
BIT(ffs(ANT_A) - 1) = BIT(ffs(BIT(0)) - 1) = BIT(0) = ANT_A.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Emmanuel Grumbach 2013-04-14 14:41:03 +03:00 committed by Johannes Berg
parent 178bdb5791
commit d7dad550e6
1 changed files with 3 additions and 2 deletions
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5
drivers/net/wireless/iwlwifi/mvm/utils.c
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@ -253,8 +253,9 @@ int iwl_mvm_rx_fw_error(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
u8 first_antenna(u8 mask)
{
BUILD_BUG_ON(ANT_A != BIT(0)); /* using ffs is wrong if not */
WARN_ON_ONCE(!mask); /* ffs will return 0 if mask is zeroed */
return (u8)(BIT(ffs(mask)));
if (WARN_ON_ONCE(!mask)) /* ffs will return 0 if mask is zeroed */
return BIT(0);
return BIT(ffs(mask) - 1);
}
/*