USB: Fix of_usb_get_dr_mode_by_phy with a shared phy block

Some SoCs have a single phy-hw-block with multiple phys, this is
modelled by a single phy dts node, so we end up with multiple
controller nodes with a phys property pointing to the phy-node
of the otg-phy.

Only one of these controllers typically is an otg controller, yet we
were checking the first controller who uses a phy from the block and
then end up looking for a dr_mode property in e.g. the ehci controller.

This commit fixes this by adding an arg0 parameter to
of_usb_get_dr_mode_by_phy and make of_usb_get_dr_mode_by_phy
check that this matches the phandle args[0] value when looking for
the otg controller.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

1 files changed, 20 insertions, 6 deletions

diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
index e3d01619d6b3..5ef8da6e67c3 100644
--- a/drivers/usb/common/common.c
+++ b/drivers/usb/common/common.c
@@ -131,15 +131,17 @@ EXPORT_SYMBOL_GPL(usb_get_dr_mode);
  * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
  * which is associated with the given phy device_node
  * @np: Pointer to the given phy device_node
+ * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
+ *        phys which do not have phy-cells
  *
  * In dts a usb controller associates with phy devices.  The function gets
  * the string from property 'dr_mode' of the controller associated with the
  * given phy device node, and returns the correspondig enum usb_dr_mode.
  */
-enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *phy_np)
+enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
 {
         struct device_node *controller = NULL;
-        struct device_node *phy;
+        struct of_phandle_args args;
         const char *dr_mode;
         int index;
         int err;
@@ -148,12 +150,24 @@ enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *phy_np)
                 controller = of_find_node_with_property(controller, "phys");
                 index = 0;
                 do {
-                        phy = of_parse_phandle(controller, "phys", index);
-                        of_node_put(phy);
-                        if (phy == phy_np)
+                        if (arg0 == -1) {
+                                args.np = of_parse_phandle(controller, "phys",
+                                                        index);
+                                args.args_count = 0;
+                        } else {
+                                err = of_parse_phandle_with_args(controller,
+                                                        "phys", "#phy-cells",
+                                                        index, &args);
+                                if (err)
+                                        break;
+                        }
+
+                        of_node_put(args.np);
+                        if (args.np == np && (args.args_count == 0 ||
+                                              args.args[0] == arg0))
                                 goto finish;
                         index++;
-                } while (phy);
+                } while (args.np);
         } while (controller);
 
 finish: