+static ssize_t max_number_of_rtt_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+ unsigned int rtt;
+ int ret;
+
+ if (kstrtouint(buf, 0, &rtt))
+ return -EINVAL;
+
+ down(&hba->host_sem);
+ if (!ufshcd_is_user_access_allowed(hba)) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ ufshcd_rpm_get_sync(hba);
+ ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
+ QUERY_ATTR_IDN_MAX_NUM_OF_RTT, 0, 0, &rtt);
+ ufshcd_rpm_put_sync(hba);
+
+out:
+ up(&hba->host_sem);
+ return ret < 0 ? ret : count;
+}