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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2015 - 2016 Xilinx, Inc.
* Copyright (C) 2017 National Instruments Corp
* Written by Michal Simek
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <i2c.h>
#include <asm-generic/gpio.h>
DECLARE_GLOBAL_DATA_PTR;
enum pca_type {
PCA9544,
PCA9547,
PCA9548
};
struct chip_desc {
u8 enable;
enum muxtype {
pca954x_ismux = 0,
pca954x_isswi,
} muxtype;
u32 width;
};
struct pca954x_priv {
u32 addr; /* I2C mux address */
u32 width; /* I2C mux width - number of busses */
struct gpio_desc gpio_mux_reset;
};
static const struct chip_desc chips[] = {
[PCA9544] = {
.enable = 0x4,
.muxtype = pca954x_ismux,
.width = 4,
},
[PCA9547] = {
.enable = 0x8,
.muxtype = pca954x_ismux,
.width = 8,
},
[PCA9548] = {
.enable = 0x8,
.muxtype = pca954x_isswi,
.width = 8,
},
};
static int pca954x_deselect(struct udevice *mux, struct udevice *bus,
uint channel)
{
struct pca954x_priv *priv = dev_get_priv(mux);
uchar byte = 0;
return dm_i2c_write(mux, priv->addr, &byte, 1);
}
static int pca954x_select(struct udevice *mux, struct udevice *bus,
uint channel)
{
struct pca954x_priv *priv = dev_get_priv(mux);
const struct chip_desc *chip = &chips[dev_get_driver_data(mux)];
uchar byte;
if (chip->muxtype == pca954x_ismux)
byte = channel | chip->enable;
else
byte = 1 << channel;
return dm_i2c_write(mux, priv->addr, &byte, 1);
}
static const struct i2c_mux_ops pca954x_ops = {
.select = pca954x_select,
.deselect = pca954x_deselect,
};
static const struct udevice_id pca954x_ids[] = {
{ .compatible = "nxp,pca9544", .data = PCA9544 },
{ .compatible = "nxp,pca9547", .data = PCA9547 },
{ .compatible = "nxp,pca9548", .data = PCA9548 },
{ }
};
static int pca954x_ofdata_to_platdata(struct udevice *dev)
{
struct pca954x_priv *priv = dev_get_priv(dev);
const struct chip_desc *chip = &chips[dev_get_driver_data(dev)];
priv->addr = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), "reg", 0);
if (!priv->addr) {
debug("MUX not found\n");
return -ENODEV;
}
priv->width = chip->width;
if (!priv->width) {
debug("No I2C MUX width specified\n");
return -EINVAL;
}
debug("Device %s at 0x%x with width %d\n",
dev->name, priv->addr, priv->width);
return 0;
}
static int pca954x_probe(struct udevice *dev)
{
if (IS_ENABLED(CONFIG_DM_GPIO)) {
struct pca954x_priv *priv = dev_get_priv(dev);
int err;
err = gpio_request_by_name(dev, "reset-gpios", 0,
&priv->gpio_mux_reset, GPIOD_IS_OUT);
/* it's optional so only bail if we get a real error */
if (err && (err != -ENOENT))
return err;
/* dm will take care of polarity */
if (dm_gpio_is_valid(&priv->gpio_mux_reset))
dm_gpio_set_value(&priv->gpio_mux_reset, 0);
}
return 0;
}
static int pca954x_remove(struct udevice *dev)
{
if (IS_ENABLED(CONFIG_DM_GPIO)) {
struct pca954x_priv *priv = dev_get_priv(dev);
if (dm_gpio_is_valid(&priv->gpio_mux_reset))
dm_gpio_free(dev, &priv->gpio_mux_reset);
}
return 0;
}
U_BOOT_DRIVER(pca954x) = {
.name = "pca954x",
.id = UCLASS_I2C_MUX,
.of_match = pca954x_ids,
.probe = pca954x_probe,
.remove = pca954x_remove,
.ops = &pca954x_ops,
.ofdata_to_platdata = pca954x_ofdata_to_platdata,
.priv_auto_alloc_size = sizeof(struct pca954x_priv),
};
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