/*
   * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
   *
   * (C) Copyright 2012
   * Heiko Schocher, DENX Software Engineering, hs@denx.de.
   *
   * Multibus/multiadapter I2C core functions (wrappers)
   *

   * SPDX-License-Identifier:	GPL-2.0+

   */
  #include <common.h>
  #include <i2c.h>
  
  struct i2c_adapter *i2c_get_adapter(int index)
  {
  	struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter,
  						i2c);
  	int max = ll_entry_count(struct i2c_adapter, i2c);
  	int i;
  
  	if (index >= max) {
  		printf("Error, wrong i2c adapter %d max %d possible
  ",
  		       index, max);
  		return i2c_adap_p;
  	}
  	if (index == 0)
  		return i2c_adap_p;
  
  	for (i = 0; i < index; i++)
  		i2c_adap_p++;
  
  	return i2c_adap_p;
  }
  
  #if !defined(CONFIG_SYS_I2C_DIRECT_BUS)
  struct i2c_bus_hose i2c_bus[CONFIG_SYS_NUM_I2C_BUSES] =
  			CONFIG_SYS_I2C_BUSES;
  #endif
  
  DECLARE_GLOBAL_DATA_PTR;

  #ifndef CONFIG_SYS_I2C_DIRECT_BUS
  /*
   * i2c_mux_set()
   * -------------
   *
   * This turns on the given channel on I2C multiplexer chip connected to
   * a given I2C adapter directly or via other multiplexers. In the latter
   * case the entire multiplexer chain must be initialized first starting
   * with the one connected directly to the adapter. When disabling a chain
   * muxes must be programmed in reverse order, starting with the one
   * farthest from the adapter.
   *
   * mux_id is the multiplexer chip type from defined in i2c.h. So far only
   * NXP (Philips) PCA954x multiplexers are supported. Switches are NOT
   * supported (anybody uses them?)
   */
  
  static int i2c_mux_set(struct i2c_adapter *adap, int mux_id, int chip,
  			int channel)
  {
  	uint8_t	buf;
  	int ret;
  
  	/* channel < 0 - turn off the mux */
  	if (channel < 0) {
  		buf = 0;
  		ret = adap->write(adap, chip, 0, 0, &buf, 1);
  		if (ret)
  			printf("%s: Could not turn off the mux.
  ", __func__);
  		return ret;
  	}
  
  	switch (mux_id) {
  	case I2C_MUX_PCA9540_ID:
  	case I2C_MUX_PCA9542_ID:
  		if (channel > 1)
  			return -1;
  		buf = (uint8_t)((channel & 0x01) | (1 << 2));
  		break;
  	case I2C_MUX_PCA9544_ID:
  		if (channel > 3)
  			return -1;
  		buf = (uint8_t)((channel & 0x03) | (1 << 2));
  		break;

         	case I2C_MUX_PCA9546_ID:
                 	if (channel > 4)
                         	return -1;
                 	buf = (uint8_t)((channel & 0x04) | (1 << 3));
                 	break;

  	case I2C_MUX_PCA9547_ID:
  		if (channel > 7)
  			return -1;
  		buf = (uint8_t)((channel & 0x07) | (1 << 3));
  		break;

  	case I2C_MUX_PCA9548_ID:
  		if (channel > 7)
  			return -1;
  		buf = (uint8_t)(0x01 << channel);
  		break;

  	default:
  		printf("%s: wrong mux id: %d
  ", __func__, mux_id);
  		return -1;
  	}
  
  	ret = adap->write(adap, chip, 0, 0, &buf, 1);
  	if (ret)
  		printf("%s: could not set mux: id: %d chip: %x channel: %d
  ",
  		       __func__, mux_id, chip, channel);
  	return ret;
  }
  
  static int i2c_mux_set_all(void)
  {
  	struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS];
  	int i;
  
  	/* Connect requested bus if behind muxes */
  	if (i2c_bus_tmp->next_hop[0].chip != 0) {
  		/* Set all muxes along the path to that bus */
  		for (i = 0; i < CONFIG_SYS_I2C_MAX_HOPS; i++) {
  			int	ret;
  
  			if (i2c_bus_tmp->next_hop[i].chip == 0)
  				break;
  
  			ret = i2c_mux_set(I2C_ADAP,
  					i2c_bus_tmp->next_hop[i].mux.id,
  					i2c_bus_tmp->next_hop[i].chip,
  					i2c_bus_tmp->next_hop[i].channel);
  			if (ret != 0)
  				return ret;
  		}
  	}
  	return 0;
  }

  static int i2c_mux_disconnect_all(void)

  {
  	struct	i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS];
  	int	i;

  	uint8_t	buf = 0;

  
  	if (I2C_ADAP->init_done == 0)
  		return 0;
  
  	/* Disconnect current bus (turn off muxes if any) */
  	if ((i2c_bus_tmp->next_hop[0].chip != 0) &&
  	    (I2C_ADAP->init_done != 0)) {
  		i = CONFIG_SYS_I2C_MAX_HOPS;
  		do {
  			uint8_t	chip;
  			int ret;
  
  			chip = i2c_bus_tmp->next_hop[--i].chip;
  			if (chip == 0)
  				continue;
  
  			ret = I2C_ADAP->write(I2C_ADAP, chip, 0, 0, &buf, 1);
  			if (ret != 0) {

  				printf("i2c: mux disconnect error
  ");

  				return ret;
  			}
  		} while (i > 0);
  	}
  
  	return 0;
  }
  #endif
  
  /*
   * i2c_init_bus():
   * ---------------
   *
   * Initializes one bus. Will initialize the parent adapter. No current bus
   * changes, no mux (if any) setup.
   */
  static void i2c_init_bus(unsigned int bus_no, int speed, int slaveaddr)
  {
  	if (bus_no >= CONFIG_SYS_NUM_I2C_BUSES)
  		return;
  
  	I2C_ADAP->init(I2C_ADAP, speed, slaveaddr);
  
  	if (gd->flags & GD_FLG_RELOC) {
  		I2C_ADAP->init_done = 1;
  		I2C_ADAP->speed = speed;
  		I2C_ADAP->slaveaddr = slaveaddr;
  	}
  }
  
  /* implement possible board specific board init */

  __weak void i2c_init_board(void)

  {
  }

  /* implement possible for i2c specific early i2c init */
  __weak void i2c_early_init_f(void)
  {
  }

  /*
   * i2c_init_all():
   *
   * not longer needed, will deleted. Actual init the SPD_BUS
   * for compatibility.
   * i2c_adap[] must be initialized beforehead with function pointers and
   * data, including speed and slaveaddr.
   */
  void i2c_init_all(void)
  {
  	i2c_init_board();
  	i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
  	return;
  }
  
  /*
   * i2c_get_bus_num():
   * ------------------
   *
   *  Returns index of currently active I2C bus.  Zero-based.
   */
  unsigned int i2c_get_bus_num(void)
  {
  	return gd->cur_i2c_bus;
  }
  
  /*
   * i2c_set_bus_num():
   * ------------------
   *
   *  Change the active I2C bus. Subsequent read/write calls will
   *  go to this one. Sets all of the muxes in a proper condition
   *  if that bus is behind muxes.
   *  If previously selected bus is behind the muxes turns off all the
   *  muxes along the path to that bus.
   *
   *	bus - bus index, zero based
   *
   *	Returns: 0 on success, not 0 on failure
   */
  int i2c_set_bus_num(unsigned int bus)
  {

  	int max;
  
  	if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0))
  		return 0;

  #ifndef CONFIG_SYS_I2C_DIRECT_BUS
  	if (bus >= CONFIG_SYS_NUM_I2C_BUSES)
  		return -1;
  #endif

  	max = ll_entry_count(struct i2c_adapter, i2c);
  	if (I2C_ADAPTER(bus) >= max) {
  		printf("Error, wrong i2c adapter %d max %d possible
  ",
  		       I2C_ADAPTER(bus), max);
  		return -2;
  	}

  
  #ifndef CONFIG_SYS_I2C_DIRECT_BUS

  	i2c_mux_disconnect_all();

  #endif
  
  	gd->cur_i2c_bus = bus;
  	if (I2C_ADAP->init_done == 0)
  		i2c_init_bus(bus, I2C_ADAP->speed, I2C_ADAP->slaveaddr);
  
  #ifndef CONFIG_SYS_I2C_DIRECT_BUS
  	i2c_mux_set_all();
  #endif
  	return 0;
  }
  
  /*
   * Probe the given I2C chip address.  Returns 0 if a chip responded,
   * not 0 on failure.
   */
  int i2c_probe(uint8_t chip)
  {
  	return I2C_ADAP->probe(I2C_ADAP, chip);
  }
  
  /*
   * Read/Write interface:
   *   chip:    I2C chip address, range 0..127
   *   addr:    Memory (register) address within the chip
   *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
   *              memories, 0 for register type devices with only one
   *              register)
   *   buffer:  Where to read/write the data
   *   len:     How many bytes to read/write
   *
   *   Returns: 0 on success, not 0 on failure
   */
  int i2c_read(uint8_t chip, unsigned int addr, int alen,
  				uint8_t *buffer, int len)
  {
  	return I2C_ADAP->read(I2C_ADAP, chip, addr, alen, buffer, len);
  }
  
  int i2c_write(uint8_t chip, unsigned int addr, int alen,
  				uint8_t *buffer, int len)
  {
  	return I2C_ADAP->write(I2C_ADAP, chip, addr, alen, buffer, len);
  }
  
  unsigned int i2c_set_bus_speed(unsigned int speed)
  {
  	unsigned int ret;
  
  	if (I2C_ADAP->set_bus_speed == NULL)
  		return 0;
  	ret = I2C_ADAP->set_bus_speed(I2C_ADAP, speed);
  	if (gd->flags & GD_FLG_RELOC)

  		I2C_ADAP->speed = (ret == 0) ? speed : 0;

  
  	return ret;
  }
  
  unsigned int i2c_get_bus_speed(void)
  {
  	struct i2c_adapter *cur = I2C_ADAP;
  	return cur->speed;
  }
  
  uint8_t i2c_reg_read(uint8_t addr, uint8_t reg)
  {
  	uint8_t buf;

  	i2c_read(addr, reg, 1, &buf, 1);
  
  #ifdef DEBUG
  	printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x
  ",
  	       __func__, i2c_get_bus_num(), addr, reg, buf);
  #endif
  
  	return buf;
  }
  
  void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val)
  {

  #ifdef DEBUG
  	printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x
  ",
  	       __func__, i2c_get_bus_num(), addr, reg, val);
  #endif
  
  	i2c_write(addr, reg, 1, &val, 1);
  }

  __weak void i2c_init(int speed, int slaveaddr)

  {
  	i2c_init_bus(i2c_get_bus_num(), speed, slaveaddr);
  }