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/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012,2013 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file pwm.c
* @brief PWM Driver code.
*
* @addtogroup PWM
* @{
*/
#include "ch.h"
#include "hal.h"
#if HAL_USE_PWM || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver local definitions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief PWM Driver initialization.
* @note This function is implicitly invoked by @p halInit(), there is
* no need to explicitly initialize the driver.
*
* @init
*/
void pwmInit(void) {
pwm_lld_init();
}
/**
* @brief Initializes the standard part of a @p PWMDriver structure.
*
* @param[out] pwmp pointer to a @p PWMDriver object
*
* @init
*/
void pwmObjectInit(PWMDriver *pwmp) {
pwmp->state = PWM_STOP;
pwmp->config = NULL;
#if defined(PWM_DRIVER_EXT_INIT_HOOK)
PWM_DRIVER_EXT_INIT_HOOK(pwmp);
#endif
}
/**
* @brief Configures and activates the PWM peripheral.
* @note Starting a driver that is already in the @p PWM_READY state
* disables all the active channels.
*
* @param[in] pwmp pointer to a @p PWMDriver object
* @param[in] config pointer to a @p PWMConfig object
*
* @api
*/
void pwmStart(PWMDriver *pwmp, const PWMConfig *config) {
chDbgCheck((pwmp != NULL) && (config != NULL), "pwmStart");
chSysLock();
chDbgAssert((pwmp->state == PWM_STOP) || (pwmp->state == PWM_READY),
"pwmStart(), #1", "invalid state");
pwmp->config = config;
pwmp->period = config->period;
pwm_lld_start(pwmp);
pwmp->state = PWM_READY;
chSysUnlock();
}
/**
* @brief Deactivates the PWM peripheral.
*
* @param[in] pwmp pointer to a @p PWMDriver object
*
* @api
*/
void pwmStop(PWMDriver *pwmp) {
chDbgCheck(pwmp != NULL, "pwmStop");
chSysLock();
chDbgAssert((pwmp->state == PWM_STOP) || (pwmp->state == PWM_READY),
"pwmStop(), #1", "invalid state");
pwm_lld_stop(pwmp);
pwmp->state = PWM_STOP;
chSysUnlock();
}
/**
* @brief Changes the period the PWM peripheral.
* @details This function changes the period of a PWM unit that has already
* been activated using @p pwmStart().
* @pre The PWM unit must have been activated using @p pwmStart().
* @post The PWM unit period is changed to the new value.
* @note If a period is specified that is shorter than the pulse width
* programmed in one of the channels then the behavior is not
* guaranteed.
*
* @param[in] pwmp pointer to a @p PWMDriver object
* @param[in] period new cycle time in ticks
*
* @api
*/
void pwmChangePeriod(PWMDriver *pwmp, pwmcnt_t period) {
chDbgCheck(pwmp != NULL, "pwmChangePeriod");
chSysLock();
chDbgAssert(pwmp->state == PWM_READY,
"pwmChangePeriod(), #1", "invalid state");
pwmChangePeriodI(pwmp, period);
chSysUnlock();
}
/**
* @brief Enables a PWM channel.
* @pre The PWM unit must have been activated using @p pwmStart().
* @post The channel is active using the specified configuration.
* @note Depending on the hardware implementation this function has
* effect starting on the next cycle (recommended implementation)
* or immediately (fallback implementation).
*
* @param[in] pwmp pointer to a @p PWMDriver object
* @param[in] channel PWM channel identifier (0...PWM_CHANNELS-1)
* @param[in] width PWM pulse width as clock pulses number
*
* @api
*/
void pwmEnableChannel(PWMDriver *pwmp,
pwmchannel_t channel,
pwmcnt_t width) {
chDbgCheck((pwmp != NULL) && (channel < PWM_CHANNELS),
"pwmEnableChannel");
chSysLock();
chDbgAssert(pwmp->state == PWM_READY,
"pwmEnableChannel(), #1", "not ready");
pwm_lld_enable_channel(pwmp, channel, width);
chSysUnlock();
}
/**
* @brief Disables a PWM channel.
* @pre The PWM unit must have been activated using @p pwmStart().
* @post The channel is disabled and its output line returned to the
* idle state.
* @note Depending on the hardware implementation this function has
* effect starting on the next cycle (recommended implementation)
* or immediately (fallback implementation).
*
* @param[in] pwmp pointer to a @p PWMDriver object
* @param[in] channel PWM channel identifier (0...PWM_CHANNELS-1)
*
* @api
*/
void pwmDisableChannel(PWMDriver *pwmp, pwmchannel_t channel) {
chDbgCheck((pwmp != NULL) && (channel < PWM_CHANNELS),
"pwmEnableChannel");
chSysLock();
chDbgAssert(pwmp->state == PWM_READY,
"pwmDisableChannel(), #1", "not ready");
pwm_lld_disable_channel(pwmp, channel);
chSysUnlock();
}
#endif /* HAL_USE_PWM */
/** @} */
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