usb: dwc3: dwc3-omap: return -EPROBE_DEFER if probe has not yet executed

return -EPROBE_DEFER from dwc3_omap_mailbox in dwc3-omap.c, if the probe of
dwc3-omap has not yet been executed or failed.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
index 546f1fd84920..2fe9723ff1df 100644
--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -138,11 +138,14 @@ static inline void dwc3_omap_writel(void __iomem *base, u32 offset, u32 value)
         writel(value, base + offset);
 }
 
-void dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
+int dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
 {
         u32                     val;
         struct dwc3_omap        *omap = _omap;
 
+        if (!omap)
+                return -EPROBE_DEFER;
+
         switch (status) {
         case OMAP_DWC3_ID_GROUND:
                 dev_dbg(omap->dev, "ID GND\n");
@@ -185,7 +188,7 @@ void dwc3_omap_mailbox(enum omap_dwc3_vbus_id_status status)
                 dev_dbg(omap->dev, "ID float\n");
         }
 
-        return;
+        return 0;
 }
 EXPORT_SYMBOL_GPL(dwc3_omap_mailbox);