text: /* Copyright 2014 The Chromium OS Authors. All rights reserved.
   * Use of this source code is governed by a BSD-style license that can be
   * found in the LICENSE file.
   *
   * NXP PCA9534 I/O expander
   */
  
  #include "i2c.h"
  #include "ioexpander_pca9534.h"
  
  static int pca9534_pin_read(const int port, const uint16_t addr_flags,
  			    int reg, int pin, int *val)
  {
  	int ret;
  	ret = i2c_read8(port, addr_flags, reg, val);
  	*val = (*val & BIT(pin)) ? 1 : 0;
  	return ret;
  }
  
  static int pca9534_pin_write(const int port, const uint16_t addr_flags,
  			     int reg, int pin, int val)
  {
  	int ret, v;
  	ret = i2c_read8(port, addr_flags, reg, &v);
  	if (ret != EC_SUCCESS)
  		return ret;
  	v &= ~BIT(pin);
  	if (val)
  		v |= 1 << pin;
  	return i2c_write8(port, addr_flags, reg, v);
  }
  
  int pca9534_get_level(const int port, const uint16_t addr_flags,
  		      int pin, int *level)
  {
  	return pca9534_pin_read(port, addr_flags,
  				PCA9534_REG_INPUT, pin, level);
  }
  
  int pca9534_set_level(const int port, const uint16_t addr_flags,
  		      int pin, int level)
  {
  	return pca9534_pin_write(port, addr_flags,
  				 PCA9534_REG_OUTPUT, pin, level);
  }
  
  int pca9534_config_pin(const int port, const uint16_t addr_flags,
  		       int pin, int is_input)
  {
  	return pca9534_pin_write(port, addr_flags,
  				 PCA9534_REG_CONFIG, pin, is_input);
  }
  