blob: 10336919adb556ba15290e268aad5c6187d5ffa4 [file] [log] [blame]
Tom Rini83d290c2018-05-06 17:58:06 -04001// SPDX-License-Identifier: GPL-2.0+
Simon Glass3d1957f2015-08-03 08:19:21 -06002/*
3 * Copyright (c) 2015 Google, Inc
4 * Written by Simon Glass <sjg@chromium.org>
Simon Glass3d1957f2015-08-03 08:19:21 -06005 */
6
7#include <common.h>
8#include <dm.h>
9#include <errno.h>
10#include <i2c.h>
11#include <dm/lists.h>
12#include <dm/root.h>
13
14DECLARE_GLOBAL_DATA_PTR;
15
16/**
17 * struct i2c_mux: Information the uclass stores about an I2C mux
18 *
19 * @selected: Currently selected mux, or -1 for none
20 * @i2c_bus: I2C bus to use for communcation
21 */
22struct i2c_mux {
23 int selected;
24 struct udevice *i2c_bus;
25};
26
27/**
28 * struct i2c_mux_bus: Information about each bus the mux controls
29 *
30 * @channel: Channel number used to select this bus
31 */
32struct i2c_mux_bus {
33 uint channel;
34};
35
36/* Find out the mux channel number */
37static int i2c_mux_child_post_bind(struct udevice *dev)
38{
39 struct i2c_mux_bus *plat = dev_get_parent_platdata(dev);
40 int channel;
41
Simon Glasse160f7d2017-01-17 16:52:55 -070042 channel = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), "reg", -1);
Simon Glass3d1957f2015-08-03 08:19:21 -060043 if (channel < 0)
44 return -EINVAL;
45 plat->channel = channel;
46
47 return 0;
48}
49
50/* Find the I2C buses selected by this mux */
51static int i2c_mux_post_bind(struct udevice *mux)
52{
Simon Glass45a26862017-05-18 20:09:07 -060053 ofnode node;
Simon Glass3d1957f2015-08-03 08:19:21 -060054 int ret;
Simon Glass3d1957f2015-08-03 08:19:21 -060055
56 debug("%s: %s\n", __func__, mux->name);
57 /*
58 * There is no compatible string in the sub-nodes, so we must manually
59 * bind these
60 */
Simon Glass45a26862017-05-18 20:09:07 -060061 dev_for_each_subnode(node, mux) {
Simon Glass3d1957f2015-08-03 08:19:21 -060062 struct udevice *dev;
63 const char *name;
64
Simon Glass45a26862017-05-18 20:09:07 -060065 name = ofnode_get_name(node);
Simon Glass3d1957f2015-08-03 08:19:21 -060066 ret = device_bind_driver_to_node(mux, "i2c_mux_bus_drv", name,
Simon Glass45a26862017-05-18 20:09:07 -060067 node, &dev);
Simon Glass3d1957f2015-08-03 08:19:21 -060068 debug(" - bind ret=%d, %s\n", ret, dev ? dev->name : NULL);
69 if (ret)
70 return ret;
71 }
72
73 return 0;
74}
75
76/* Set up the mux ready for use */
77static int i2c_mux_post_probe(struct udevice *mux)
78{
79 struct i2c_mux *priv = dev_get_uclass_priv(mux);
80 int ret;
81
82 debug("%s: %s\n", __func__, mux->name);
83 priv->selected = -1;
84
Moritz Fischer12e8d582017-01-16 09:46:06 -080085 /* if parent is of i2c uclass already, we'll take that, otherwise
86 * look if we find an i2c-parent phandle
87 */
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,
91 priv->i2c_bus->name);
92 return 0;
93 }
94
Simon Glass3d1957f2015-08-03 08:19:21 -060095 ret = uclass_get_device_by_phandle(UCLASS_I2C, mux, "i2c-parent",
96 &priv->i2c_bus);
97 if (ret)
98 return ret;
99 debug("%s: bus=%p/%s\n", __func__, priv->i2c_bus, priv->i2c_bus->name);
100
101 return 0;
102}
103
104int i2c_mux_select(struct udevice *dev)
105{
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);
109
110 if (!ops->select)
111 return -ENOSYS;
112
113 return ops->select(mux, dev, plat->channel);
114}
115
116int i2c_mux_deselect(struct udevice *dev)
117{
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);
121
122 if (!ops->deselect)
123 return -ENOSYS;
124
125 return ops->deselect(mux, dev, plat->channel);
126}
127
128static int i2c_mux_bus_set_bus_speed(struct udevice *dev, unsigned int speed)
129{
130 struct udevice *mux = dev->parent;
131 struct i2c_mux *priv = dev_get_uclass_priv(mux);
132 int ret, ret2;
133
134 ret = i2c_mux_select(dev);
135 if (ret)
136 return ret;
137 ret = dm_i2c_set_bus_speed(priv->i2c_bus, speed);
138 ret2 = i2c_mux_deselect(dev);
139
140 return ret ? ret : ret2;
141}
142
143static int i2c_mux_bus_probe(struct udevice *dev, uint chip_addr,
144 uint chip_flags)
145{
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);
149 int ret, ret2;
150
151 debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
152 if (!ops->probe_chip)
153 return -ENOSYS;
154 ret = i2c_mux_select(dev);
155 if (ret)
156 return ret;
157 ret = ops->probe_chip(priv->i2c_bus, chip_addr, chip_flags);
158 ret2 = i2c_mux_deselect(dev);
159
160 return ret ? ret : ret2;
161}
162
163static int i2c_mux_bus_xfer(struct udevice *dev, struct i2c_msg *msg,
164 int nmsgs)
165{
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);
169 int ret, ret2;
170
171 debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
172 if (!ops->xfer)
173 return -ENOSYS;
174 ret = i2c_mux_select(dev);
175 if (ret)
176 return ret;
177 ret = ops->xfer(priv->i2c_bus, msg, nmsgs);
178 ret2 = i2c_mux_deselect(dev);
179
180 return ret ? ret : ret2;
181}
182
183static 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,
187};
188
189U_BOOT_DRIVER(i2c_mux_bus) = {
190 .name = "i2c_mux_bus_drv",
191 .id = UCLASS_I2C,
Simon Glass3d1957f2015-08-03 08:19:21 -0600192 .ops = &i2c_mux_bus_ops,
193};
194
195UCLASS_DRIVER(i2c_mux) = {
196 .id = UCLASS_I2C_MUX,
197 .name = "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,
203};