firmware: xilinx: always check API version for IOCTL/QUERY

Currently, we are not checking feature check version for PM APIs as
the support may or may not there in the firmware. To check the whether
the feature check API is supported or not in the firmware, allow
checking for its own version.

Signed-off-by: Ronak Jain <ronak.jain@xilinx.com>
Link: https://lore.kernel.org/r/1649242526-17493-4-git-send-email-ronak.jain@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/firmware/xilinx/zynqmp.c

@@ -175,7 +175,7 @@ static noinline int do_fw_call_hvc(u64 arg0, u64 arg1, u64 arg2,
 	return zynqmp_pm_ret_code((enum pm_ret_status)res.a0);
 }
 
-static int do_feature_check_call(const u32 api_id, u32 *ret_payload)
+static int __do_feature_check_call(const u32 api_id, u32 *ret_payload)
 {
 	int ret;
 	u64 smc_arg[2];
@@ -192,22 +192,12 @@ static int do_feature_check_call(const u32 api_id, u32 *ret_payload)
 	return ret;
 }
 
-/**
- * zynqmp_pm_feature() - Check whether given feature is supported or not and
- *			 store supported IOCTL/QUERY ID mask
- * @api_id:		API ID to check
- *
- * Return: Returns status, either success or error+reason
- */
-int zynqmp_pm_feature(const u32 api_id)
+static int do_feature_check_call(const u32 api_id)
 {
 	int ret;
 	u32 ret_payload[PAYLOAD_ARG_CNT];
 	struct pm_api_feature_data *feature_data;
 
-	if (!feature_check_enabled)
-		return 0;
-
 	/* Check for existing entry in hash table for given api */
 	hash_for_each_possible(pm_api_features_map, feature_data, hentry,
 			       api_id) {
@@ -221,7 +211,7 @@ int zynqmp_pm_feature(const u32 api_id)
 		return -ENOMEM;
 
 	feature_data->pm_api_id = api_id;
-	ret = do_feature_check_call(api_id, ret_payload);
+	ret = __do_feature_check_call(api_id, ret_payload);
 
 	feature_data->feature_status = ret;
 	hash_add(pm_api_features_map, &feature_data->hentry, api_id);
@@ -237,6 +227,25 @@ int zynqmp_pm_feature(const u32 api_id)
 }
 EXPORT_SYMBOL_GPL(zynqmp_pm_feature);
 
+/**
+ * zynqmp_pm_feature() - Check whether given feature is supported or not and
+ *			 store supported IOCTL/QUERY ID mask
+ * @api_id:		API ID to check
+ *
+ * Return: Returns status, either success or error+reason
+ */
+int zynqmp_pm_feature(const u32 api_id)
+{
+	int ret;
+
+	if (!feature_check_enabled)
+		return 0;
+
+	ret = do_feature_check_call(api_id);
+
+	return ret;
+}
+
 /**
  * zynqmp_pm_is_function_supported() - Check whether given IOCTL/QUERY function
  *				       is supported or not
@@ -255,7 +264,7 @@ int zynqmp_pm_is_function_supported(const u32 api_id, const u32 id)
 		return -EINVAL;
 
 	/* Check feature check API version */
-	ret = zynqmp_pm_feature(PM_FEATURE_CHECK);
+	ret = do_feature_check_call(PM_FEATURE_CHECK);
 	if (ret < 0)
 		return ret;
 
@@ -265,7 +274,7 @@ int zynqmp_pm_is_function_supported(const u32 api_id, const u32 id)
 		 * Call feature check for IOCTL/QUERY API to get IOCTL ID or
 		 * QUERY ID feature status.
 		 */
-		ret = zynqmp_pm_feature(api_id);
+		ret = do_feature_check_call(api_id);
 		if (ret < 0)
 			return ret;