ath10k: deduplicate bitrate to rate idx conversion

It's possible to derive rate index from bitrate
without any additional mapping structures/logic.

This should have little to none impact on
performance since this is only done for management
frames and the previous approach wasn't
particularly optimized.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/mac.c

@@ -104,6 +104,18 @@ u8 ath10k_mac_hw_rate_to_idx(const struct ieee80211_supported_band *sband,
 	return 0;
 }
 
+u8 ath10k_mac_bitrate_to_idx(const struct ieee80211_supported_band *sband,
+			     u32 bitrate)
+{
+	int i;
+
+	for (i = 0; i < sband->n_bitrates; i++)
+		if (sband->bitrates[i].bitrate == bitrate)
+			return i;
+
+	return 0;
+}
+
 /**********/
 /* Crypto */
 /**********/

drivers/net/wireless/ath/ath10k/mac.h

@@ -55,8 +55,11 @@ bool ath10k_mac_is_peer_wep_key_set(struct ath10k *ar, const u8 *addr,
 				    u8 keyidx);
 void ath10k_mac_handle_beacon(struct ath10k *ar, struct sk_buff *skb);
 void ath10k_mac_handle_beacon_miss(struct ath10k *ar, u32 vdev_id);
+
 u8 ath10k_mac_hw_rate_to_idx(const struct ieee80211_supported_band *sband,
 			     u8 hw_rate);
+u8 ath10k_mac_bitrate_to_idx(const struct ieee80211_supported_band *sband,
+			     u32 bitrate);
 
 static inline struct ath10k_vif *ath10k_vif_to_arvif(struct ieee80211_vif *vif)
 {

drivers/net/wireless/ath/ath10k/wmi.c

@@ -1352,63 +1352,6 @@ static inline enum ieee80211_band phy_mode_to_band(u32 phy_mode)
 	return band;
 }
 
-static inline u8 get_rate_idx(u32 rate, enum ieee80211_band band)
-{
-	u8 rate_idx = 0;
-
-	/* rate in Kbps */
-	switch (rate) {
-	case 1000:
-		rate_idx = 0;
-		break;
-	case 2000:
-		rate_idx = 1;
-		break;
-	case 5500:
-		rate_idx = 2;
-		break;
-	case 11000:
-		rate_idx = 3;
-		break;
-	case 6000:
-		rate_idx = 4;
-		break;
-	case 9000:
-		rate_idx = 5;
-		break;
-	case 12000:
-		rate_idx = 6;
-		break;
-	case 18000:
-		rate_idx = 7;
-		break;
-	case 24000:
-		rate_idx = 8;
-		break;
-	case 36000:
-		rate_idx = 9;
-		break;
-	case 48000:
-		rate_idx = 10;
-		break;
-	case 54000:
-		rate_idx = 11;
-		break;
-	default:
-		break;
-	}
-
-	if (band == IEEE80211_BAND_5GHZ) {
-		if (rate_idx > 3)
-			/* Omit CCK rates */
-			rate_idx -= 4;
-		else
-			rate_idx = 0;
-	}
-
-	return rate_idx;
-}
-
 /* If keys are configured, HW decrypts all frames
  * with protected bit set. Mark such frames as decrypted.
  */
@@ -1490,6 +1433,7 @@ int ath10k_wmi_event_mgmt_rx(struct ath10k *ar, struct sk_buff *skb)
 	struct wmi_mgmt_rx_ev_arg arg = {};
 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 	struct ieee80211_hdr *hdr;
+	struct ieee80211_supported_band *sband;
 	u32 rx_status;
 	u32 channel;
 	u32 phy_mode;
@@ -1560,9 +1504,11 @@ int ath10k_wmi_event_mgmt_rx(struct ath10k *ar, struct sk_buff *skb)
 	if (phy_mode == MODE_11B && status->band == IEEE80211_BAND_5GHZ)
 		ath10k_dbg(ar, ATH10K_DBG_MGMT, "wmi mgmt rx 11b (CCK) on 5GHz\n");
 
+	sband = &ar->mac.sbands[status->band];
+
 	status->freq = ieee80211_channel_to_frequency(channel, status->band);
 	status->signal = snr + ATH10K_DEFAULT_NOISE_FLOOR;
-	status->rate_idx = get_rate_idx(rate, status->band);
+	status->rate_idx = ath10k_mac_bitrate_to_idx(sband, rate / 100);
 
 	hdr = (struct ieee80211_hdr *)skb->data;
 	fc = le16_to_cpu(hdr->frame_control);