10 #include <linux/mdio-mux.h>
16 #define DRV_DESCRIPTION "MDIO bus multiplexer driver"
33 	struct mdio_mux_parent_bus *parent;  member
39  * The parent bus' lock is used to order access to the switch_fn.
41 static int mdio_mux_read(struct mii_bus *bus, int phy_id, int regnum)  in mdio_mux_read()  argument
43 	struct mdio_mux_child_bus *cb = bus->priv;  in mdio_mux_read()
44 	struct mdio_mux_parent_bus *pb = cb->parent;  in mdio_mux_read()
47 	mutex_lock_nested(&pb->mii_bus->mdio_lock, MDIO_MUTEX_MUX);  in mdio_mux_read()
48 	r = pb->switch_fn(pb->current_child, cb->bus_number, pb->switch_data);  in mdio_mux_read()
52 	pb->current_child = cb->bus_number;  in mdio_mux_read()
54 	r = pb->mii_bus->read(pb->mii_bus, phy_id, regnum);  in mdio_mux_read()
56 	mutex_unlock(&pb->mii_bus->mdio_lock);  in mdio_mux_read()
62  * The parent bus' lock is used to order access to the switch_fn.
64 static int mdio_mux_write(struct mii_bus *bus, int phy_id,  in mdio_mux_write()  argument
67 	struct mdio_mux_child_bus *cb = bus->priv;  in mdio_mux_write()
68 	struct mdio_mux_parent_bus *pb = cb->parent;  in mdio_mux_write()
72 	mutex_lock_nested(&pb->mii_bus->mdio_lock, MDIO_MUTEX_MUX);  in mdio_mux_write()
73 	r = pb->switch_fn(pb->current_child, cb->bus_number, pb->switch_data);  in mdio_mux_write()
77 	pb->current_child = cb->bus_number;  in mdio_mux_write()
79 	r = pb->mii_bus->write(pb->mii_bus, phy_id, regnum, val);  in mdio_mux_write()
81 	mutex_unlock(&pb->mii_bus->mdio_lock);  in mdio_mux_write()
103 		return -ENODEV;  in mdio_mux_init()
107 						   "mdio-parent-bus", 0);  in mdio_mux_init()
110 			return -ENODEV;  in mdio_mux_init()
114 			ret_val = -EPROBE_DEFER;  in mdio_mux_init()
120 		get_device(&parent_bus->dev);  in mdio_mux_init()
125 		ret_val = -ENOMEM;  in mdio_mux_init()
129 	pb->switch_data = data;  in mdio_mux_init()
130 	pb->switch_fn = switch_fn;  in mdio_mux_init()
131 	pb->current_child = -1;  in mdio_mux_init()
132 	pb->parent_id = parent_count++;  in mdio_mux_init()
133 	pb->mii_bus = parent_bus;  in mdio_mux_init()
135 	ret_val = -ENODEV;  in mdio_mux_init()
149 			ret_val = -ENOMEM;  in mdio_mux_init()
152 		cb->bus_number = v;  in mdio_mux_init()
153 		cb->parent = pb;  in mdio_mux_init()
155 		cb->mii_bus = mdiobus_alloc();  in mdio_mux_init()
156 		if (!cb->mii_bus) {  in mdio_mux_init()
157 			ret_val = -ENOMEM;  in mdio_mux_init()
161 		cb->mii_bus->priv = cb;  in mdio_mux_init()
163 		cb->mii_bus->name = "mdio_mux";  in mdio_mux_init()
164 		snprintf(cb->mii_bus->id, MII_BUS_ID_SIZE, "%x.%x",  in mdio_mux_init()
165 			 pb->parent_id, v);  in mdio_mux_init()
166 		cb->mii_bus->parent = dev;  in mdio_mux_init()
167 		cb->mii_bus->read = mdio_mux_read;  in mdio_mux_init()
168 		cb->mii_bus->write = mdio_mux_write;  in mdio_mux_init()
169 		r = of_mdiobus_register(cb->mii_bus, child_bus_node);  in mdio_mux_init()
172 				"Error: Failed to register MDIO bus for child %pOF\n",  in mdio_mux_init()
174 			mdiobus_free(cb->mii_bus);  in mdio_mux_init()
177 			cb->next = pb->children;  in mdio_mux_init()
178 			pb->children = cb;  in mdio_mux_init()
181 	if (pb->children) {  in mdio_mux_init()
189 	put_device(&parent_bus->dev);  in mdio_mux_init()
199 	struct mdio_mux_child_bus *cb = pb->children;  in mdio_mux_uninit()
202 		mdiobus_unregister(cb->mii_bus);  in mdio_mux_uninit()
203 		mdiobus_free(cb->mii_bus);  in mdio_mux_uninit()
204 		cb = cb->next;  in mdio_mux_uninit()
207 	put_device(&pb->mii_bus->dev);  in mdio_mux_uninit()