1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (c) 2015 Google, Inc
4 * Written by Simon Glass <sjg@chromium.org>
14 DECLARE_GLOBAL_DATA_PTR;
17 * struct i2c_mux: Information the uclass stores about an I2C mux
19 * @selected: Currently selected mux, or -1 for none
20 * @i2c_bus: I2C bus to use for communcation
24 struct udevice *i2c_bus;
28 * struct i2c_mux_bus: Information about each bus the mux controls
30 * @channel: Channel number used to select this bus
36 /* Find out the mux channel number */
37 static int i2c_mux_child_post_bind(struct udevice *dev)
39 struct i2c_mux_bus *plat = dev_get_parent_platdata(dev);
42 channel = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), "reg", -1);
45 plat->channel = channel;
50 /* Find the I2C buses selected by this mux */
51 static int i2c_mux_post_bind(struct udevice *mux)
56 debug("%s: %s\n", __func__, mux->name);
58 * There is no compatible string in the sub-nodes, so we must manually
61 dev_for_each_subnode(node, mux) {
65 name = ofnode_get_name(node);
66 ret = device_bind_driver_to_node(mux, "i2c_mux_bus_drv", name,
68 debug(" - bind ret=%d, %s\n", ret, dev ? dev->name : NULL);
76 /* Set up the mux ready for use */
77 static int i2c_mux_post_probe(struct udevice *mux)
79 struct i2c_mux *priv = dev_get_uclass_priv(mux);
82 debug("%s: %s\n", __func__, mux->name);
85 /* if parent is of i2c uclass already, we'll take that, otherwise
86 * look if we find an i2c-parent phandle
88 if (UCLASS_I2C == device_get_uclass_id(mux->parent)) {
89 priv->i2c_bus = dev_get_parent(mux);
90 debug("%s: bus=%p/%s\n", __func__, priv->i2c_bus,
95 ret = uclass_get_device_by_phandle(UCLASS_I2C, mux, "i2c-parent",
99 debug("%s: bus=%p/%s\n", __func__, priv->i2c_bus, priv->i2c_bus->name);
104 int i2c_mux_select(struct udevice *dev)
106 struct i2c_mux_bus *plat = dev_get_parent_platdata(dev);
107 struct udevice *mux = dev->parent;
108 struct i2c_mux_ops *ops = i2c_mux_get_ops(mux);
113 return ops->select(mux, dev, plat->channel);
116 int i2c_mux_deselect(struct udevice *dev)
118 struct i2c_mux_bus *plat = dev_get_parent_platdata(dev);
119 struct udevice *mux = dev->parent;
120 struct i2c_mux_ops *ops = i2c_mux_get_ops(mux);
125 return ops->deselect(mux, dev, plat->channel);
128 static int i2c_mux_bus_set_bus_speed(struct udevice *dev, unsigned int speed)
130 struct udevice *mux = dev->parent;
131 struct i2c_mux *priv = dev_get_uclass_priv(mux);
134 ret = i2c_mux_select(dev);
137 ret = dm_i2c_set_bus_speed(priv->i2c_bus, speed);
138 ret2 = i2c_mux_deselect(dev);
140 return ret ? ret : ret2;
143 static int i2c_mux_bus_probe(struct udevice *dev, uint chip_addr,
146 struct udevice *mux = dev->parent;
147 struct i2c_mux *priv = dev_get_uclass_priv(mux);
148 struct dm_i2c_ops *ops = i2c_get_ops(priv->i2c_bus);
151 debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
152 if (!ops->probe_chip)
154 ret = i2c_mux_select(dev);
157 ret = ops->probe_chip(priv->i2c_bus, chip_addr, chip_flags);
158 ret2 = i2c_mux_deselect(dev);
160 return ret ? ret : ret2;
163 static int i2c_mux_bus_xfer(struct udevice *dev, struct i2c_msg *msg,
166 struct udevice *mux = dev->parent;
167 struct i2c_mux *priv = dev_get_uclass_priv(mux);
168 struct dm_i2c_ops *ops = i2c_get_ops(priv->i2c_bus);
171 debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
174 ret = i2c_mux_select(dev);
177 ret = ops->xfer(priv->i2c_bus, msg, nmsgs);
178 ret2 = i2c_mux_deselect(dev);
180 return ret ? ret : ret2;
183 static const struct dm_i2c_ops i2c_mux_bus_ops = {
184 .xfer = i2c_mux_bus_xfer,
185 .probe_chip = i2c_mux_bus_probe,
186 .set_bus_speed = i2c_mux_bus_set_bus_speed,
189 U_BOOT_DRIVER(i2c_mux_bus) = {
190 .name = "i2c_mux_bus_drv",
192 .ops = &i2c_mux_bus_ops,
195 UCLASS_DRIVER(i2c_mux) = {
196 .id = UCLASS_I2C_MUX,
198 .post_bind = i2c_mux_post_bind,
199 .post_probe = i2c_mux_post_probe,
200 .per_device_auto_alloc_size = sizeof(struct i2c_mux),
201 .per_child_platdata_auto_alloc_size = sizeof(struct i2c_mux_bus),
202 .child_post_bind = i2c_mux_child_post_bind,