u-boot/drivers/i2c/muxes/i2c-mux-uclass.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

203 lines
4.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <i2c.h>
#include <dm/lists.h>
#include <dm/root.h>
DECLARE_GLOBAL_DATA_PTR;
/**
* struct i2c_mux: Information the uclass stores about an I2C mux
*
* @selected: Currently selected mux, or -1 for none
* @i2c_bus: I2C bus to use for communcation
*/
struct i2c_mux {
int selected;
struct udevice *i2c_bus;
};
/**
* struct i2c_mux_bus: Information about each bus the mux controls
*
* @channel: Channel number used to select this bus
*/
struct i2c_mux_bus {
uint channel;
};
/* Find out the mux channel number */
static int i2c_mux_child_post_bind(struct udevice *dev)
{
struct i2c_mux_bus *plat = dev_get_parent_platdata(dev);
int channel;
channel = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), "reg", -1);
if (channel < 0)
return -EINVAL;
plat->channel = channel;
return 0;
}
/* Find the I2C buses selected by this mux */
static int i2c_mux_post_bind(struct udevice *mux)
{
ofnode node;
int ret;
debug("%s: %s\n", __func__, mux->name);
/*
* There is no compatible string in the sub-nodes, so we must manually
* bind these
*/
dev_for_each_subnode(node, mux) {
struct udevice *dev;
const char *name;
name = ofnode_get_name(node);
ret = device_bind_driver_to_node(mux, "i2c_mux_bus_drv", name,
node, &dev);
debug(" - bind ret=%d, %s\n", ret, dev ? dev->name : NULL);
if (ret)
return ret;
}
return 0;
}
/* Set up the mux ready for use */
static int i2c_mux_post_probe(struct udevice *mux)
{
struct i2c_mux *priv = dev_get_uclass_priv(mux);
int ret;
debug("%s: %s\n", __func__, mux->name);
priv->selected = -1;
/* if parent is of i2c uclass already, we'll take that, otherwise
* look if we find an i2c-parent phandle
*/
if (UCLASS_I2C == device_get_uclass_id(mux->parent)) {
priv->i2c_bus = dev_get_parent(mux);
debug("%s: bus=%p/%s\n", __func__, priv->i2c_bus,
priv->i2c_bus->name);
return 0;
}
ret = uclass_get_device_by_phandle(UCLASS_I2C, mux, "i2c-parent",
&priv->i2c_bus);
if (ret)
return ret;
debug("%s: bus=%p/%s\n", __func__, priv->i2c_bus, priv->i2c_bus->name);
return 0;
}
int i2c_mux_select(struct udevice *dev)
{
struct i2c_mux_bus *plat = dev_get_parent_platdata(dev);
struct udevice *mux = dev->parent;
struct i2c_mux_ops *ops = i2c_mux_get_ops(mux);
if (!ops->select)
return -ENOSYS;
return ops->select(mux, dev, plat->channel);
}
int i2c_mux_deselect(struct udevice *dev)
{
struct i2c_mux_bus *plat = dev_get_parent_platdata(dev);
struct udevice *mux = dev->parent;
struct i2c_mux_ops *ops = i2c_mux_get_ops(mux);
if (!ops->deselect)
return -ENOSYS;
return ops->deselect(mux, dev, plat->channel);
}
static int i2c_mux_bus_set_bus_speed(struct udevice *dev, unsigned int speed)
{
struct udevice *mux = dev->parent;
struct i2c_mux *priv = dev_get_uclass_priv(mux);
int ret, ret2;
ret = i2c_mux_select(dev);
if (ret)
return ret;
ret = dm_i2c_set_bus_speed(priv->i2c_bus, speed);
ret2 = i2c_mux_deselect(dev);
return ret ? ret : ret2;
}
static int i2c_mux_bus_probe(struct udevice *dev, uint chip_addr,
uint chip_flags)
{
struct udevice *mux = dev->parent;
struct i2c_mux *priv = dev_get_uclass_priv(mux);
struct dm_i2c_ops *ops = i2c_get_ops(priv->i2c_bus);
int ret, ret2;
debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
if (!ops->probe_chip)
return -ENOSYS;
ret = i2c_mux_select(dev);
if (ret)
return ret;
ret = ops->probe_chip(priv->i2c_bus, chip_addr, chip_flags);
ret2 = i2c_mux_deselect(dev);
return ret ? ret : ret2;
}
static int i2c_mux_bus_xfer(struct udevice *dev, struct i2c_msg *msg,
int nmsgs)
{
struct udevice *mux = dev->parent;
struct i2c_mux *priv = dev_get_uclass_priv(mux);
struct dm_i2c_ops *ops = i2c_get_ops(priv->i2c_bus);
int ret, ret2;
debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
if (!ops->xfer)
return -ENOSYS;
ret = i2c_mux_select(dev);
if (ret)
return ret;
ret = ops->xfer(priv->i2c_bus, msg, nmsgs);
ret2 = i2c_mux_deselect(dev);
return ret ? ret : ret2;
}
static const struct dm_i2c_ops i2c_mux_bus_ops = {
.xfer = i2c_mux_bus_xfer,
.probe_chip = i2c_mux_bus_probe,
.set_bus_speed = i2c_mux_bus_set_bus_speed,
};
U_BOOT_DRIVER(i2c_mux_bus) = {
.name = "i2c_mux_bus_drv",
.id = UCLASS_I2C,
.ops = &i2c_mux_bus_ops,
};
UCLASS_DRIVER(i2c_mux) = {
.id = UCLASS_I2C_MUX,
.name = "i2c_mux",
.post_bind = i2c_mux_post_bind,
.post_probe = i2c_mux_post_probe,
.per_device_auto_alloc_size = sizeof(struct i2c_mux),
.per_child_platdata_auto_alloc_size = sizeof(struct i2c_mux_bus),
.child_post_bind = i2c_mux_child_post_bind,
};