rt-thread-official/bsp/imx6ul/platform/include/gpt.h

225 lines
8.6 KiB
C

/*
* Copyright (c) 2011-2012, Freescale Semiconductor, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* o Redistributions of source code must retain the above copyright notice, this list
* of conditions and the following disclaimer.
*
* o Redistributions in binary form must reproduce the above copyright notice, this
* list of conditions and the following disclaimer in the documentation and/or
* other materials provided with the distribution.
*
* o Neither the name of Freescale Semiconductor, Inc. nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
//! @addtogroup diag_gpt
//! @{
/*!
* @file gpt.h
* @brief GPT driver public interface.
*/
#ifndef __GPT_H__
#define __GPT_H__
#include "imx_timer.h"
#include "sdk.h"
////////////////////////////////////////////////////////////////////////////////
// Definitions
////////////////////////////////////////////////////////////////////////////////
//! @brief Possible events for the GPT.
//!
//! These constants are intended to be combined together to form a bitmask. Several
//! of the GPT driver APIs use such a bitmask. For instance, gpt_counter_enable()
//! accepts a bitmask that selects the events for which interrupts should be enabled.
//!
//! Note that the values of these enums happen to be the bitmasks for the respective
//! fields in the HW_GPT_SR and HW_GPT_IR registers, so a mask constructed from them
//! can be used directly with register values.
enum _gpt_events
{
kGPTNoEvent = 0, //!< No events enabled.
kGPTRollover = 1 << 5, //!< Rollover event.
kGPTInputCapture1 = 1 << 3, //!< Input capture 1 event.
kGPTInputCapture2 = 1 << 4, //!< Input capture 2 event.
kGPTOutputCompare1 = 1 << 0, //!< Output compare 1 event.
kGPTOutputCompare2 = 1 << 1, //!< Output compare 2 event.
kGPTOutputCompare3 = 1 << 2, //!< Output compare 3 event.
//! Combined mask of all GPT events.
kGPTAllEvents = kGPTRollover | kGPTInputCapture1 | kGPTInputCapture2
| kGPTOutputCompare1 | kGPTOutputCompare2 | kGPTOutputCompare3
};
//! @brief GPT counter modes.
enum _gpt_counter_mode
{
RESTART_MODE = 0,
FREE_RUN_MODE = 1
};
//! @brief Supported input capture modes.
enum _gpt_capture_modes
{
INPUT_CAP_DISABLE = 0, //!< input capture event disabled
INPUT_CAP_RISING_EDGE = 1, //!< input capture event on a rising edge
INPUT_CAP_FALLING_EDGE = 2, //!< input capture event on a falling edge
INPUT_CAP_BOTH_EDGE = 3 //!< input capture event on a both edge
};
//! @brief Supported output modes.
enum _gpt_compare_modes
{
OUTPUT_CMP_DISABLE = 0, //!< output disconnected from pad
OUTPUT_CMP_TOGGLE = 1, //!< output toggle mode
OUTPUT_CMP_CLEAR = 2, //!< output set low mode
OUTPUT_CMP_SET = 3, //!< output set high mode
OUTPUT_CMP_LOWPULSE = 4 //!< output set high mode
};
////////////////////////////////////////////////////////////////////////////////
// API
////////////////////////////////////////////////////////////////////////////////
#if defined(__cplusplus)
extern "C" {
#endif
/*!
* @brief Initialize the GPT timer.
*
* @param clock_src Source clock of the counter: CLKSRC_OFF, CLKSRC_IPG_CLK,
* CLKSRC_PER_CLK, CLKSRC_CKIL, CLKSRC_CLKIN.
* @param prescaler Prescaler of the source clock from 1 to 4096.
* @param counter_mode Counter mode: FREE_RUN_MODE or RESTART_MODE.
* @param low_power_mode Low power during which the timer is enabled:
* WAIT_MODE_EN and/or STOP_MODE_EN.
*/
void gpt_init(uint32_t clock_src, uint32_t prescaler, uint32_t counter_mode, uint32_t low_power_mode);
/*!
* @brief Setup GPT interrupt.
*
* It enables or disables the related HW module interrupt, and attached the
* related sub-routine into the vector table.
*
* @param irq_subroutine the GPT interrupt interrupt routine.
* @param enableIt Pass true to enable the interrupt.
*/
void gpt_setup_interrupt(void (*irq_subroutine)(void), bool enableIt);
/*!
* @brief Enable the GPT module.
*
* Used typically when the gpt_init is done, and other interrupt related settings are ready.
*
* If a value of #kGPTNoEvent is passed for @a irq_mode, then no interrupts will be enabled.
* This effectively puts the timer into polling mode, where you must call gpt_get_x_event()
* to check for an event having occurred.
*
* @param irq_mode Mask of events to enable interrupts for, such as #kGPTRollover or
* #kGPTOutputCompare1. See the #_gpt_events enum for the complete list. Pass
* #kGPTNoEvent to prevent any interrupts from being enabled, which effectively puts
* the timer into polling mode.
*/
void gpt_counter_enable(uint32_t irq_mode);
/*!
* @brief Disable the counter.
*
* It saves power when not used.
*
*/
void gpt_counter_disable(void);
/*!
* @brief Get rollover event flag and clear it if set.
*
* This function can typically be used for polling method, but
* is also used to clear the status compare flag in IRQ mode.
*
* @return Either 0 of kGPTRollover.
*/
uint32_t gpt_get_rollover_event(void);
/*!
* @brief Get a captured value when an event occured, and clear the flag if set.
*
* Use this function to check for an input capture event having occurred, either in
* the event ISR or to check manually in polling mode. Pass the input channel to check
* in the @a flag parameter. If that channel fired, its captured timer value will be
* read and placed in @a capture_val (if not NULL). The event that fired will be cleared
* and its event mask returned as the return value from the function. If no event
* occurred, the function returns 0.
*
* @param flag Which channel to check, either #kGPTInputCapture1 or #kGPTInputCapture2.
* Only one channel may be specified.
* @param capture_val The capture register value is returned through this parameter if
* the specified event occurred. May be NULL if not required.
* @return Mask of input specified capture event that occurred, or 0 if no event occurred.
*/
uint32_t gpt_get_capture_event(uint8_t flag, uint32_t * capture_val);
/*!
* @brief Set the input capture mode.
*
* @param cap_input The input capture channel to configure, either #kGPTInputCapture1
* or #kGPTInputCapture2.
* @param cap_input_mode Capture input mode: #INPUT_CAP_DISABLE, #INPUT_CAP_BOTH_EDGE,
* #INPUT_CAP_FALLING_EDGE, #INPUT_CAP_RISING_EDGE.
*/
void gpt_set_capture_event(uint8_t cap_input, uint8_t cap_input_mode);
/*!
* @brief Get a compare event flag and clear it if set.
*
* This function can typically be used for polling method, but
* is also used to clear the status compare flag in IRQ mode.
*
* @param flag Checked compare event flag such GPTSR_OF1, GPTSR_OF2, GPTSR_OF3.
* @return The value of the compare event flag.
*/
uint32_t gpt_get_compare_event(uint8_t flag);
/*!
* @brief Set a compare event by programming the compare register and
* compare output mode.
*
* @param cmp_output The channel to configure. Must be one of #kGPTOutputCompare1,
* #kGPTOutputCompare2, or #kGPTOutputCompare3.
* @param cmp_output_mode Compare output mode: #OUTPUT_CMP_DISABLE, #OUTPUT_CMP_TOGGLE,
* #OUTPUT_CMP_CLEAR, #OUTPUT_CMP_SET, #OUTPUT_CMP_LOWPULSE.
* @param cmp_value Compare value for the compare register.
*/
void gpt_set_compare_event(uint8_t cmp_output, uint8_t cmp_output_mode, uint32_t cmp_value);
#if defined(__cplusplus)
}
#endif
//! @}
#endif //__GPT_H__
////////////////////////////////////////////////////////////////////////////////
// EOF
////////////////////////////////////////////////////////////////////////////////