1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/misc/ti-st/st_core.c b/drivers/misc/ti-st/st_core.c
index f7bb96f3a424..dd2c879faff6 100644
--- a/drivers/misc/ti-st/st_core.c
+++ b/drivers/misc/ti-st/st_core.c
@@ -52,6 +52,24 @@ static void remove_channel_from_table(struct st_data_s *st_gdata,
         st_gdata->list[proto->chnl_id] = NULL;
 }
 
+/*
+ * called from KIM during firmware download.
+ *
+ * This is a wrapper function to tty->ops->write_room.
+ * It returns number of free space available in
+ * uart tx buffer.
+ */
+int st_get_uart_wr_room(struct st_data_s *st_gdata)
+{
+        struct tty_struct *tty;
+        if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) {
+                pr_err("tty unavailable to perform write");
+                return -1;
+        }
+        tty = st_gdata->tty;
+        return tty->ops->write_room(tty);
+}
+
 /* can be called in from
  * -- KIM (during fw download)
  * -- ST Core (during st_write)