62 lines
1.6 KiB
C
62 lines
1.6 KiB
C
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/* Copyright 2012 The Chromium OS Authors. All rights reserved.
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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/* ADC interface for Chrome EC */
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#ifndef __CROS_EC_ADC_H
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#define __CROS_EC_ADC_H
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#include "common.h"
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#define ADC_READ_ERROR -1 /* Value returned by adc_read_channel() on error */
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/*
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* Boards which use the ADC interface must provide enum adc_channel in the
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* board.h file. See chip/$CHIP/adc_chip.h for additional chip-specific
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* requirements.
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*/
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/**
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* Read an ADC channel.
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*
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* @param ch Channel to read
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*
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* @return The scaled ADC value, or ADC_READ_ERROR if error.
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*/
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int adc_read_channel(enum adc_channel ch);
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/**
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* Enable ADC watchdog. Note that interrupts might come in repeatedly very
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* quickly when ADC output goes out of the accepted range.
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*
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* @param ain_id The AIN to be watched by the watchdog.
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* @param high The high threshold that the watchdog would trigger
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* an interrupt when exceeded.
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* @param low The low threshold.
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*
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* @return EC_SUCCESS, or non-zero if any error.
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*/
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int adc_enable_watchdog(int ain_id, int high, int low);
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/**
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* Disable ADC watchdog.
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*
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* @return EC_SUCCESS, or non-zero if any error.
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*/
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int adc_disable_watchdog(void);
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/**
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* Set the delay between ADC watchdog samples. This can be used as a trade-off
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* of power consumption and performance.
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*
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* @param delay_ms The delay in milliseconds between two ADC watchdog
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* samples.
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*
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* @return EC_SUCCESS, or non-zero if any error or not supported.
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*/
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int adc_set_watchdog_delay(int delay_ms);
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#endif /* __CROS_EC_ADC_H */
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