/* SPDX-License-Identifier: GPL-2.0-or-later */

  /*
   *
   * i2c-mux.h - functions for the i2c-bus mux support
   *
   * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
   * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
   * Michael Lawnick <michael.lawnick.ext@nsn.com>

   */
  
  #ifndef _LINUX_I2C_MUX_H
  #define _LINUX_I2C_MUX_H
  
  #ifdef __KERNEL__

  #include <linux/bitops.h>

  struct i2c_mux_core {
  	struct i2c_adapter *parent;
  	struct device *dev;

  	unsigned int mux_locked:1;
  	unsigned int arbitrator:1;
  	unsigned int gate:1;

  
  	void *priv;
  
  	int (*select)(struct i2c_mux_core *, u32 chan_id);
  	int (*deselect)(struct i2c_mux_core *, u32 chan_id);
  
  	int num_adapters;
  	int max_adapters;

  	struct i2c_adapter *adapter[];

  };
  
  struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent,
  				   struct device *dev, int max_adapters,
  				   int sizeof_priv, u32 flags,
  				   int (*select)(struct i2c_mux_core *, u32),
  				   int (*deselect)(struct i2c_mux_core *, u32));

  /* flags for i2c_mux_alloc */

  #define I2C_MUX_LOCKED     BIT(0)
  #define I2C_MUX_ARBITRATOR BIT(1)
  #define I2C_MUX_GATE       BIT(2)

  static inline void *i2c_mux_priv(struct i2c_mux_core *muxc)
  {
  	return muxc->priv;
  }

  struct i2c_adapter *i2c_root_adapter(struct device *dev);

  /*

   * Called to create an i2c bus on a multiplexed bus segment.
   * The chan_id parameter is passed to the select and deselect
   * callback functions to perform hardware-specific mux control.
   */
  int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
  			u32 force_nr, u32 chan_id,
  			unsigned int class);

  void i2c_mux_del_adapters(struct i2c_mux_core *muxc);

  
  #endif /* __KERNEL__ */
  
  #endif /* _LINUX_I2C_MUX_H */