usb: dwc3: core: support optional PHYs

Since PHYs for dwc3 is optional (not all SoCs having PHYs for DWC3
should be programmed), do not return from probe if the USB PHY library
returns -ENODEV as that indicates the platform does not have a
programmable PHY.

While this can be considered as a temporary fix, a long term solution
would be to add 'nop' PHY for platforms that does not have programmable
PHY.

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

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 8c627c9a51305c7ec80ccb315483449cb1e52360..c89570cc0689e563a103eb6c7aaa3779c12b34f4 100644 (file)
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -534,32 +534,26 @@ static int dwc3_probe(struct platform_device *pdev)
 
        if (IS_ERR(dwc->usb2_phy)) {
                ret = PTR_ERR(dwc->usb2_phy);
-
-               /*
-                * if -ENXIO is returned, it means PHY layer wasn't
-                * enabled, so it makes no sense to return -EPROBE_DEFER
-                * in that case, since no PHY driver will ever probe.
-                */
-               if (ret == -ENXIO)
+               if (ret == -ENXIO || ret == -ENODEV) {
+                       dwc->usb2_phy = NULL;
+               } else if (ret == -EPROBE_DEFER) {
                        return ret;
-
-               dev_err(dev, "no usb2 phy configured\n");
-               return -EPROBE_DEFER;
+               } else {
+                       dev_err(dev, "no usb2 phy configured\n");
+                       return ret;
+               }
        }
 
        if (IS_ERR(dwc->usb3_phy)) {
                ret = PTR_ERR(dwc->usb3_phy);
-
-               /*
-                * if -ENXIO is returned, it means PHY layer wasn't
-                * enabled, so it makes no sense to return -EPROBE_DEFER
-                * in that case, since no PHY driver will ever probe.
-                */
-               if (ret == -ENXIO)
+               if (ret == -ENXIO || ret == -ENODEV) {
+                       dwc->usb3_phy = NULL;
+               } else if (ret == -EPROBE_DEFER) {
                        return ret;
-
-               dev_err(dev, "no usb3 phy configured\n");
-               return -EPROBE_DEFER;
+               } else {
+                       dev_err(dev, "no usb3 phy configured\n");
+                       return ret;
+               }
        }
 
        dwc->xhci_resources[0].start = res->start;