linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * GPIO-controlled multiplexer driver

 *

 * Copyright (C) 2017 Axentia Technologies AB

 *

 * Author: Peter Rosin <peda@axentia.se>

 */

​

#include <linux/err.h>

#include <linux/gpio/consumer.h>

#include <linux/module.h>

#include <linux/mux/driver.h>

#include <linux/of_platform.h>

#include <linux/platform_device.h>

#include <linux/property.h>

​

struct mux_gpio {

    struct gpio_descs *gpios;

};

​

static int mux_gpio_set(struct mux_control *mux, int state)

{

    struct mux_gpio *mux_gpio = mux_chip_priv(mux->chip);

    DECLARE_BITMAP(values, BITS_PER_TYPE(state));

​

    values[0] = state;

​

    gpiod_set_array_value_cansleep(mux_gpio->gpios->ndescs,

                       mux_gpio->gpios->desc,

                       mux_gpio->gpios->info, values);

​

    return 0;

}

​

static const struct mux_control_ops mux_gpio_ops = {

    .set = mux_gpio_set,

};

​

static const struct of_device_id mux_gpio_dt_ids[] = {

    { .compatible = "gpio-mux", },

    { /* sentinel */ }

};

MODULE_DEVICE_TABLE(of, mux_gpio_dt_ids);

​

static int mux_gpio_probe(struct platform_device *pdev)

{

    struct device *dev = &pdev->dev;

    struct mux_chip *mux_chip;

    struct mux_gpio *mux_gpio;

    int pins;

    s32 idle_state;

    int ret;

​

    pins = gpiod_count(dev, "mux");

    if (pins < 0)

        return pins;

​

    mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*mux_gpio));

    if (IS_ERR(mux_chip))

        return PTR_ERR(mux_chip);

​

    mux_gpio = mux_chip_priv(mux_chip);