1 files changed, 38 insertions, 0 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 4d7b83fbc32f..be75a3a0424e 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1006,3 +1006,41 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
 
         return -EBUSY;
 }
+
+int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
+                           const u8 *rates, unsigned int n_rates,
+                           u32 *mask)
+{
+        int i, j;
+
+        if (!sband)
+                return -EINVAL;
+
+        if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
+                return -EINVAL;
+
+        *mask = 0;
+
+        for (i = 0; i < n_rates; i++) {
+                int rate = (rates[i] & 0x7f) * 5;
+                bool found = false;
+
+                for (j = 0; j < sband->n_bitrates; j++) {
+                        if (sband->bitrates[j].bitrate == rate) {
+                                found = true;
+                                *mask |= BIT(j);
+                                break;
+                        }
+                }
+                if (!found)
+                        return -EINVAL;
+        }
+
+        /*
+         * mask must have at least one bit set here since we
+         * didn't accept a 0-length rates array nor allowed
+         * entries in the array that didn't exist
+         */
+
+        return 0;
+}