text: /* Copyright 2016 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.
   */
  
  #include <string.h>
  #include "common.h"
  #include "cts_common.h"
  #include "cts_i2c.h"
  #include "i2c.h"
  #include "registers.h"
  #include "task.h"
  #include "timer.h"
  #include "uart.h"
  #include "watchdog.h"
  
  static uint8_t inbox[I2C_MAX_HOST_PACKET_SIZE + 2];
  static char data_received;
  
  void i2c_data_received(int port, uint8_t *buf, int len)
  {
  	memcpy(inbox, buf, len);
  	data_received = 1;
  }
  
  /* CTS I2C protocol implementation */
  int i2c_set_response(int port, uint8_t *buf, int len)
  {
  	switch (buf[0]) {
  	case READ8_OFF:
  		buf[0] = READ8_DATA;
  		return 1;
  	case READ16_OFF:
  		buf[0] = READ16_DATA & 0xFF;
  		buf[1] = (READ16_DATA >> 8) & 0xFF;
  		return 2;
  	case READ32_OFF:
  		buf[0] = READ32_DATA & 0xFF;
  		buf[1] = (READ32_DATA >> 8) & 0xFF;
  		buf[2] = (READ32_DATA >> 16) & 0xFF;
  		buf[3] = (READ32_DATA >> 24) & 0xFF;
  		return 4;
  	default:
  		return 0;
  	}
  }
  
  static int wait_for_in_flag(uint32_t timeout_ms)
  {
  	uint64_t start_time, end_time;
  
  	start_time = get_time().val;
  	end_time = start_time + timeout_ms * 1000;
  
  	while (get_time().val < end_time) {
  		if (data_received)
  			return 0;
  		msleep(5);
  		watchdog_reload();
  	}
  	return 1;
  }
  
  void clean_state(void)
  {
  	memset(inbox, 0, sizeof(inbox));
  	data_received = 0;
  }
  
  enum cts_rc write8_test(void)
  {
  	int in;
  
  	if (wait_for_in_flag(100))
  		return CTS_RC_TIMEOUT;
  	if (inbox[0] != WRITE8_OFF)
  		return CTS_RC_FAILURE;
  	in = inbox[1];
  	if (in != WRITE8_DATA)
  		return CTS_RC_FAILURE;
  
  	return CTS_RC_SUCCESS;
  }
  
  enum cts_rc write16_test(void)
  {
  	int in;
  
  	if (wait_for_in_flag(100))
  		return CTS_RC_TIMEOUT;
  	if (inbox[0] != WRITE16_OFF)
  		return CTS_RC_FAILURE;
  	in = inbox[2] << 8 | inbox[1] << 0;
  	if (in != WRITE16_DATA)
  		return CTS_RC_FAILURE;
  
  	return CTS_RC_SUCCESS;
  }
  
  enum cts_rc write32_test(void)
  {
  	int in;
  
  	if (wait_for_in_flag(100))
  		return CTS_RC_TIMEOUT;
  	if (inbox[0] != WRITE32_OFF)
  		return CTS_RC_FAILURE;
  	in = inbox[4] << 24 | inbox[3] << 16 | inbox[2] << 8 | inbox[1];
  	if (in != WRITE32_DATA)
  		return CTS_RC_FAILURE;
  
  	return CTS_RC_SUCCESS;
  }
  
  enum cts_rc read8_test(void)
  {
  	if (wait_for_in_flag(100))
  		return CTS_RC_TIMEOUT;
  	if (inbox[0] != READ8_OFF)
  		return CTS_RC_FAILURE;
  
  	return CTS_RC_SUCCESS;
  }
  
  enum cts_rc read16_test(void)
  {
  	if (wait_for_in_flag(100))
  		return CTS_RC_TIMEOUT;
  	if (inbox[0] != READ16_OFF)
  		return CTS_RC_FAILURE;
  
  	return CTS_RC_SUCCESS;
  }
  
  enum cts_rc read32_test(void)
  {
  	if (wait_for_in_flag(100))
  		return CTS_RC_TIMEOUT;
  	if (inbox[0] != READ32_OFF)
  		return CTS_RC_FAILURE;
  
  	return CTS_RC_SUCCESS;
  }
  
  #include "cts_testlist.h"
  
  void cts_task(void)
  {
  	cts_main_loop(tests, "I2C");
  	task_wait_event(-1);
  }
  