accel/habanalabs: call to HW/FW err returns 0 when no events exist

This commit modifies the call to retrieve HW or FW error events to
return success when no events are pending, as done in the calls to
other events.
Signed-off-by: Moti Haimovski <mhaimovski@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

drivers/accel/habanalabs/common/habanalabs_ioctl.c

@@ -842,15 +842,15 @@ static int hw_err_info(struct hl_fpriv *hpriv, struct hl_info_args *args)
 	struct hw_err_info *info;
 	int rc;
 
-	if ((!user_buf_size) || (!user_buf))
+	if (!user_buf)
 		return -EINVAL;
 
-	if (user_buf_size < sizeof(struct hl_info_hw_err_event))
-		return -ENOMEM;
-
 	info = &hdev->captured_err_info.hw_err;
 	if (!info->event_info_available)
-		return -ENOENT;
+		return 0;
+
+	if (user_buf_size < sizeof(struct hl_info_hw_err_event))
+		return -ENOMEM;
 
 	rc = copy_to_user(user_buf, &info->event, sizeof(struct hl_info_hw_err_event));
 	return rc ? -EFAULT : 0;
@@ -864,15 +864,15 @@ static int fw_err_info(struct hl_fpriv *hpriv, struct hl_info_args *args)
 	struct fw_err_info *info;
 	int rc;
 
-	if ((!user_buf_size) || (!user_buf))
+	if (!user_buf)
 		return -EINVAL;
 
-	if (user_buf_size < sizeof(struct hl_info_fw_err_event))
-		return -ENOMEM;
-
 	info = &hdev->captured_err_info.fw_err;
 	if (!info->event_info_available)
-		return -ENOENT;
+		return 0;
+
+	if (user_buf_size < sizeof(struct hl_info_fw_err_event))
+		return -ENOMEM;
 
 	rc = copy_to_user(user_buf, &info->event, sizeof(struct hl_info_fw_err_event));
 	return rc ? -EFAULT : 0;