linux-imx

/*

 * Linux I2C core slave support code

 *

 * Copyright (C) 2014 by Wolfram Sang <wsa@sang-engineering.com>

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License as published by the Free

 * Software Foundation; either version 2 of the License, or (at your option)

 * any later version.

 */

​

#include <dt-bindings/i2c/i2c.h>

#include <linux/acpi.h>

#include <linux/device.h>

#include <linux/err.h>

#include <linux/i2c.h>

#include <linux/of.h>

​

#include "i2c-core.h"

​

int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb)

{

    int ret;

​

    if (!client || !slave_cb) {

        WARN(1, "insufficient data\n");

        return -EINVAL;

    }

​

    if (!(client->flags & I2C_CLIENT_SLAVE))

        dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n",

             __func__);

​

    if (!(client->flags & I2C_CLIENT_TEN)) {

        /* Enforce stricter address checking */

        ret = i2c_check_7bit_addr_validity_strict(client->addr);

        if (ret) {

            dev_err(&client->dev, "%s: invalid address\n", __func__);

            return ret;

        }

    }

​

    if (!client->adapter->algo->reg_slave) {

        dev_err(&client->dev, "%s: not supported by adapter\n", __func__);

        return -EOPNOTSUPP;

    }

​

    client->slave_cb = slave_cb;

​

    i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);

    ret = client->adapter->algo->reg_slave(client);

    i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);

​

    if (ret) {

        client->slave_cb = NULL;

        dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret);

    }

​

    return ret;

}

EXPORT_SYMBOL_GPL(i2c_slave_register);

​

int i2c_slave_unregister(struct i2c_client *client)