wcn36xx: Improve feature caps exchange

* Response format is not in the canonical format.
  wcn36xx_smd_rsp_status_check cannot be used.

* Save the FW caps in wcn36xx struct for later use.
Signed-off-by: Pontus Fuchs <pontus.fuchs@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/wcn36xx/hal.h

@@ -4384,11 +4384,13 @@ enum place_holder_in_cap_bitmap {
 	MAX_FEATURE_SUPPORTED = 128,
 };
 
+#define WCN36XX_HAL_CAPS_SIZE 4
+
 struct wcn36xx_hal_feat_caps_msg {
 
 	struct wcn36xx_hal_msg_header header;
 
-	u32 feat_caps[4];
+	u32 feat_caps[WCN36XX_HAL_CAPS_SIZE];
 } __packed;
 
 /* status codes to help debug rekey failures */

drivers/net/wireless/ath/wcn36xx/smd.c

@@ -1731,8 +1731,8 @@ static inline void clear_feat_caps(u32 *bitmap,
 
 int wcn36xx_smd_feature_caps_exchange(struct wcn36xx *wcn)
 {
-	struct wcn36xx_hal_feat_caps_msg msg_body;
-	int ret = 0;
+	struct wcn36xx_hal_feat_caps_msg msg_body, *rsp;
+	int ret = 0, i;
 
 	mutex_lock(&wcn->hal_mutex);
 	INIT_HAL_MSG(msg_body, WCN36XX_HAL_FEATURE_CAPS_EXCHANGE_REQ);
@@ -1746,12 +1746,15 @@ int wcn36xx_smd_feature_caps_exchange(struct wcn36xx *wcn)
 		wcn36xx_err("Sending hal_feature_caps_exchange failed\n");
 		goto out;
 	}
-	ret = wcn36xx_smd_rsp_status_check(wcn->hal_buf, wcn->hal_rsp_len);
-	if (ret) {
-		wcn36xx_err("hal_feature_caps_exchange response failed err=%d\n",
-			    ret);
+	if (wcn->hal_rsp_len != sizeof(*rsp)) {
+		wcn36xx_err("Invalid hal_feature_caps_exchange response");
 		goto out;
 	}
+
+	rsp = (struct wcn36xx_hal_feat_caps_msg *) wcn->hal_buf;
+
+	for (i = 0; i < WCN36XX_HAL_CAPS_SIZE; i++)
+		wcn->fw_feat_caps[i] = rsp->feat_caps[i];
 out:
 	mutex_unlock(&wcn->hal_mutex);
 	return ret;

drivers/net/wireless/ath/wcn36xx/wcn36xx.h

@@ -175,6 +175,7 @@ struct wcn36xx {
 	u8			fw_version;
 	u8			fw_minor;
 	u8			fw_major;
+	u32			fw_feat_caps[WCN36XX_HAL_CAPS_SIZE];
 
 	/* extra byte for the NULL termination */
 	u8			crm_version[WCN36XX_HAL_VERSION_LENGTH + 1];