Merge branch 'i2c-mux-dt-3' of https://github.com/peda-r/i2c-mux into i2c/for-4.9

[karo-tx-linux.git] / drivers / i2c / i2c-mux.c

diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 764f195795e406486799cfc3a640eadd94b7911f..90f59c08875098ab70228314a10a6fca01c186de 100644 (file)
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -255,6 +255,10 @@ struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent,
        muxc->dev = dev;
        if (flags & I2C_MUX_LOCKED)
                muxc->mux_locked = true;
+       if (flags & I2C_MUX_ARBITRATOR)
+               muxc->arbitrator = true;
+       if (flags & I2C_MUX_GATE)
+               muxc->gate = true;
        muxc->select = select;
        muxc->deselect = deselect;
        muxc->max_adapters = max_adapters;
@@ -335,18 +339,42 @@ int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
         * nothing if !CONFIG_OF.
         */
        if (muxc->dev->of_node) {
-               struct device_node *child;
+               struct device_node *dev_node = muxc->dev->of_node;
+               struct device_node *mux_node, *child = NULL;
                u32 reg;
 
-               for_each_child_of_node(muxc->dev->of_node, child) {
-                       ret = of_property_read_u32(child, "reg", &reg);
-                       if (ret)
-                               continue;
-                       if (chan_id == reg) {
-                               priv->adap.dev.of_node = child;
-                               break;
+               if (muxc->arbitrator)
+                       mux_node = of_get_child_by_name(dev_node, "i2c-arb");
+               else if (muxc->gate)
+                       mux_node = of_get_child_by_name(dev_node, "i2c-gate");
+               else
+                       mux_node = of_get_child_by_name(dev_node, "i2c-mux");
+
+               if (mux_node) {
+                       /* A "reg" property indicates an old-style DT entry */
+                       if (!of_property_read_u32(mux_node, "reg", &reg)) {
+                               of_node_put(mux_node);
+                               mux_node = NULL;
+                       }
+               }
+
+               if (!mux_node)
+                       mux_node = of_node_get(dev_node);
+               else if (muxc->arbitrator || muxc->gate)
+                       child = of_node_get(mux_node);
+
+               if (!child) {
+                       for_each_child_of_node(mux_node, child) {
+                               ret = of_property_read_u32(child, "reg", &reg);
+                               if (ret)
+                                       continue;
+                               if (chan_id == reg)
+                                       break;
                        }
                }
+
+               priv->adap.dev.of_node = child;
+               of_node_put(mux_node);
        }
 
        /*