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/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010 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 STM32/pwm_lld.c
* @brief STM32 PWM subsystem low level driver header.
*
* @addtogroup PWM
* @{
*/
#include "ch.h"
#include "hal.h"
#if HAL_USE_PWM || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/**
* @brief PWM1 driver identifier.
* @note The driver PWM1 allocates the complex timer TIM1 when enabled.
*/
#if defined(STM32_PWM_USE_TIM1) || defined(__DOXYGEN__)
PWMDriver PWMD1;
#endif
/**
* @brief PWM2 driver identifier.
* @note The driver PWM2 allocates the timer TIM2 when enabled.
*/
#if defined(STM32_PWM_USE_TIM2) || defined(__DOXYGEN__)
PWMDriver PWMD2;
#endif
/**
* @brief PWM3 driver identifier.
* @note The driver PWM3 allocates the timer TIM3 when enabled.
*/
#if defined(STM32_PWM_USE_TIM3) || defined(__DOXYGEN__)
PWMDriver PWMD3;
#endif
/**
* @brief PWM4 driver identifier.
* @note The driver PWM4 allocates the timer TIM4 when enabled.
*/
#if defined(STM32_PWM_USE_TIM4) || defined(__DOXYGEN__)
PWMDriver PWMD4;
#endif
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/**
* @brief Stops all channels.
*
* @param[in] pwmp pointer to a @p PWMDriver object
*/
static void stop_channels(PWMDriver *pwmp) {
pwmp->pd_enabled_channels = 0; /* All channels disabled. */
pwmp->pd_tim->CCER = 0; /* Outputs disabled. */
pwmp->pd_tim->CCR1 = 0; /* Comparator 1 disabled. */
pwmp->pd_tim->CCR2 = 0; /* Comparator 2 disabled. */
pwmp->pd_tim->CCR3 = 0; /* Comparator 3 disabled. */
pwmp->pd_tim->CCR4 = 0; /* Comparator 4 disabled. */
pwmp->pd_tim->CCMR1 = 0; /* Channels 1 and 2 frozen. */
pwmp->pd_tim->CCMR2 = 0; /* Channels 3 and 4 frozen. */
}
#if STM32_PWM_USE_TIM2 || STM32_PWM_USE_TIM3 || STM32_PWM_USE_TIM4 || \
defined(__DOXYGEN__)
/**
* @brief Common TIM2...TIM4 IRQ handler.
* @note It is assumed that the various sources are only activated if the
* associated callback pointer is not equal to @p NULL in order to not
* perform an extra check in a potentially critical interrupt handler.
*/
static void serve_interrupt(PWMDriver *pwmp) {
uint16_t sr;
sr = pwmp->pd_tim->SR & pwmp->pd_tim->DIER;
pwmp->pd_tim->SR = ~(TIM_SR_CC1IF | TIM_SR_CC2IF | TIM_SR_CC3IF |
TIM_SR_CC4IF | TIM_SR_UIF);
if ((sr & TIM_SR_CC1IF) != 0)
pwmp->pd_config->pc_channels[0].pcc_callback(pwmp);
if ((sr & TIM_SR_CC2IF) != 0)
pwmp->pd_config->pc_channels[1].pcc_callback(pwmp);
if ((sr & TIM_SR_CC3IF) != 0)
pwmp->pd_config->pc_channels[2].pcc_callback(pwmp);
if ((sr & TIM_SR_CC4IF) != 0)
pwmp->pd_config->pc_channels[3].pcc_callback(pwmp);
if ((sr & TIM_SR_UIF) != 0)
pwmp->pd_config->pc_callback(pwmp);
}
#endif /* STM32_PWM_USE_TIM2 || STM32_PWM_USE_TIM3 || STM32_PWM_USE_TIM4 */
/*===========================================================================*/
/* Driver interrupt handlers. */
/*===========================================================================*/
#if STM32_PWM_USE_TIM1
/**
* @brief TIM1 update interrupt handler.
* @note It is assumed that this interrupt is only activated if the callback
* pointer is not equal to @p NULL in order to not perform an extra
* check in a potentially critical interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(TIM1_UP_IRQHandler) {
CH_IRQ_PROLOGUE();
TIM1->SR = ~TIM_SR_UIF;
PWMD1.pd_config->pc_callback(&PWMD1);
CH_IRQ_EPILOGUE();
}
/**
* @brief TIM1 compare interrupt handler.
* @note It is assumed that the various sources are only activated if the
* associated callback pointer is not equal to @p NULL in order to not
* perform an extra check in a potentially critical interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(TIM1_CC_IRQHandler) {
uint16_t sr;
CH_IRQ_PROLOGUE();
sr = TIM1->SR & TIM1->DIER;
TIM1->SR = ~(TIM_SR_CC1IF | TIM_SR_CC2IF | TIM_SR_CC3IF | TIM_SR_CC4IF);
if ((sr & TIM_SR_CC1IF) != 0)
PWMD1.pd_config->pc_channels[0].pcc_callback(&PWMD1);
if ((sr & TIM_SR_CC2IF) != 0)
PWMD1.pd_config->pc_channels[1].pcc_callback(&PWMD1);
if ((sr & TIM_SR_CC3IF) != 0)
PWMD1.pd_config->pc_channels[2].pcc_callback(&PWMD1);
if ((sr & TIM_SR_CC4IF) != 0)
PWMD1.pd_config->pc_channels[3].pcc_callback(&PWMD1);
CH_IRQ_EPILOGUE();
}
#endif /* STM32_PWM_USE_TIM1 */
#if STM32_PWM_USE_TIM2
/**
* @brief TIM2 interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(TIM2_IRQHandler) {
CH_IRQ_PROLOGUE();
serve_interrupt(&PWMD2);
CH_IRQ_EPILOGUE();
}
#endif /* STM32_PWM_USE_TIM2 */
#if STM32_PWM_USE_TIM3
/**
* @brief TIM3 interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(TIM3_IRQHandler) {
CH_IRQ_PROLOGUE();
serve_interrupt(&PWMD3);
CH_IRQ_EPILOGUE();
}
#endif /* STM32_PWM_USE_TIM3 */
#if STM32_PWM_USE_TIM4
/**
* @brief TIM4 interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(TIM4_IRQHandler) {
CH_IRQ_PROLOGUE();
serve_interrupt(&PWMD4);
CH_IRQ_EPILOGUE();
}
#endif /* STM32_PWM_USE_TIM4 */
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level PWM driver initialization.
*
* @notapi
*/
void pwm_lld_init(void) {
#if STM32_PWM_USE_TIM1
/* TIM1 reset, ensures reset state in order to avoid trouble with JTAGs.*/
RCC->APB2RSTR = RCC_APB2RSTR_TIM1RST;
RCC->APB2RSTR = 0;
/* Driver initialization.*/
pwmObjectInit(&PWMD1);
PWMD1.pd_enabled_channels = 0;
PWMD1.pd_tim = TIM1;
#endif
#if STM32_PWM_USE_TIM2
/* TIM2 reset, ensures reset state in order to avoid trouble with JTAGs.*/
RCC->APB1RSTR = RCC_APB1RSTR_TIM2RST;
RCC->APB1RSTR = 0;
/* Driver initialization.*/
pwmObjectInit(&PWMD2);
PWMD2.pd_enabled_channels = 0;
PWMD2.pd_tim = TIM2;
#endif
#if STM32_PWM_USE_TIM3
/* TIM2 reset, ensures reset state in order to avoid trouble with JTAGs.*/
RCC->APB1RSTR = RCC_APB1RSTR_TIM3RST;
RCC->APB1RSTR = 0;
/* Driver initialization.*/
pwmObjectInit(&PWMD3);
PWMD3.pd_enabled_channels = 0;
PWMD3.pd_tim = TIM3;
#endif
#if STM32_PWM_USE_TIM4
/* TIM2 reset, ensures reset state in order to avoid trouble with JTAGs.*/
RCC->APB1RSTR = RCC_APB1RSTR_TIM4RST;
RCC->APB1RSTR = 0;
/* Driver initialization.*/
pwmObjectInit(&PWMD4);
PWMD4.pd_enabled_channels = 0;
PWMD4.pd_tim = TIM4;
#endif
}
/**
* @brief Configures and activates the PWM peripheral.
*
* @param[in] pwmp pointer to a @p PWMDriver object
*
* @notapi
*/
void pwm_lld_start(PWMDriver *pwmp) {
uint16_t ccer;
if (pwmp->pd_state == PWM_STOP) {
/* Clock activation.*/
#if STM32_PWM_USE_TIM1
if (&PWMD1 == pwmp) {
NVICEnableVector(TIM1_UP_IRQn,
CORTEX_PRIORITY_MASK(STM32_PWM_PWM1_IRQ_PRIORITY));
NVICEnableVector(TIM1_CC_IRQn,
CORTEX_PRIORITY_MASK(STM32_PWM_PWM1_IRQ_PRIORITY));
RCC->APB2ENR |= RCC_APB2ENR_TIM1EN;
}
#endif
#if STM32_PWM_USE_TIM2
if (&PWMD2 == pwmp) {
NVICEnableVector(TIM2_IRQn,
CORTEX_PRIORITY_MASK(STM32_PWM_PWM2_IRQ_PRIORITY));
RCC->APB1ENR |= RCC_APB1ENR_TIM2EN;
}
#endif
#if STM32_PWM_USE_TIM3
if (&PWMD3 == pwmp) {
NVICEnableVector(TIM3_IRQn,
CORTEX_PRIORITY_MASK(STM32_PWM_PWM3_IRQ_PRIORITY));
RCC->APB1ENR |= RCC_APB1ENR_TIM3EN;
}
#endif
#if STM32_PWM_USE_TIM4
if (&PWMD4 == pwmp) {
NVICEnableVector(TIM4_IRQn,
CORTEX_PRIORITY_MASK(STM32_PWM_PWM4_IRQ_PRIORITY));
RCC->APB1ENR |= RCC_APB1ENR_TIM4EN;
}
#endif
}
/* Reset channels.*/
stop_channels(pwmp);
/* Configuration or reconfiguration.*/
pwmp->pd_tim->CR1 = 0; /* Timer stopped. */
pwmp->pd_tim->SMCR = 0; /* Slave mode disabled. */
pwmp->pd_tim->CR2 = pwmp->pd_config->pc_cr2;
pwmp->pd_tim->PSC = pwmp->pd_config->pc_psc;
pwmp->pd_tim->CNT = 0;
pwmp->pd_tim->ARR = pwmp->pd_config->pc_arr;
/* Output enables and polarities setup.*/
ccer = 0;
switch (pwmp->pd_config->pc_channels[0].pcc_mode) {
case PWM_OUTPUT_ACTIVE_LOW:
ccer |= TIM_CCER_CC1P;
case PWM_OUTPUT_ACTIVE_HIGH:
ccer |= TIM_CCER_CC1E;
default:
;
}
switch (pwmp->pd_config->pc_channels[1].pcc_mode) {
case PWM_OUTPUT_ACTIVE_LOW:
ccer |= TIM_CCER_CC2P;
case PWM_OUTPUT_ACTIVE_HIGH:
ccer |= TIM_CCER_CC2E;
default:
;
}
switch (pwmp->pd_config->pc_channels[2].pcc_mode) {
case PWM_OUTPUT_ACTIVE_LOW:
ccer |= TIM_CCER_CC3P;
case PWM_OUTPUT_ACTIVE_HIGH:
ccer |= TIM_CCER_CC3E;
default:
;
}
switch (pwmp->pd_config->pc_channels[3].pcc_mode) {
case PWM_OUTPUT_ACTIVE_LOW:
ccer |= TIM_CCER_CC4P;
case PWM_OUTPUT_ACTIVE_HIGH:
ccer |= TIM_CCER_CC4E;
default:
;
}
pwmp->pd_tim->CCER = ccer;
pwmp->pd_tim->EGR = TIM_EGR_UG; /* Update event. */
pwmp->pd_tim->SR = 0; /* Clear pending IRQs. */
pwmp->pd_tim->DIER = pwmp->pd_config->pc_callback == NULL ? 0 : TIM_DIER_UIE;
pwmp->pd_tim->BDTR = TIM_BDTR_MOE;
pwmp->pd_tim->CR1 = TIM_CR1_ARPE | TIM_CR1_URS |
TIM_CR1_CEN; /* Timer configured and started.*/
}
/**
* @brief Deactivates the PWM peripheral.
*
* @param[in] pwmp pointer to a @p PWMDriver object
*
* @notapi
*/
void pwm_lld_stop(PWMDriver *pwmp) {
/* If in ready state then disables the PWM clock.*/
if (pwmp->pd_state == PWM_READY) {
stop_channels(pwmp);
pwmp->pd_tim->CR1 = 0;
pwmp->pd_tim->BDTR = 0;
pwmp->pd_tim->DIER = 0;
#if STM32_PWM_USE_TIM1
if (&PWMD1 == pwmp) {
NVICDisableVector(TIM1_UP_IRQn);
NVICDisableVector(TIM1_CC_IRQn);
RCC->APB2ENR &= ~RCC_APB2ENR_TIM1EN;
}
#endif
#if STM32_PWM_USE_TIM2
if (&PWMD2 == pwmp) {
NVICDisableVector(TIM2_IRQn);
RCC->APB1ENR &= ~RCC_APB1ENR_TIM2EN;
}
#endif
#if STM32_PWM_USE_TIM3
if (&PWMD3 == pwmp) {
NVICDisableVector(TIM3_IRQn);
RCC->APB1ENR &= ~RCC_APB1ENR_TIM3EN;
}
#endif
#if STM32_PWM_USE_TIM4
if (&PWMD4 == pwmp) {
NVICDisableVector(TIM4_IRQn);
RCC->APB1ENR &= ~RCC_APB1ENR_TIM4EN;
}
#endif
}
}
/**
* @brief Enables a PWM channel.
*
* @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
*
* @notapi
*/
void pwm_lld_enable_channel(PWMDriver *pwmp,
pwmchannel_t channel,
pwmcnt_t width) {
/*
* Changes the pulse width.
*/
switch (channel) {
case 0:
pwmp->pd_tim->CCR1 = width;
break;
case 1:
pwmp->pd_tim->CCR2 = width;
break;
case 2:
pwmp->pd_tim->CCR3 = width;
break;
case 3:
pwmp->pd_tim->CCR4 = width;
break;
}
if ((pwmp->pd_enabled_channels & (1 << channel)) == 0) {
/*
* The channel is not enabled yet.
*/
pwmp->pd_enabled_channels |= (1 << channel);
/*
* Setup the comparator, the channel is configured as PWM mode 1 with
* preload enabled.
*/
switch (channel) {
case 0:
pwmp->pd_tim->CCMR1 = (pwmp->pd_tim->CCMR1 & 0xFF00) |
TIM_CCMR1_OC1M_1 | TIM_CCMR1_OC1M_2 |
TIM_CCMR1_OC1PE;
pwmp->pd_tim->SR = ~TIM_SR_CC1IF;
pwmp->pd_tim->DIER |= pwmp->pd_config->pc_channels[0].pcc_callback == NULL
? 0 : TIM_DIER_CC1IE;
break;
case 1:
pwmp->pd_tim->CCMR1 = (pwmp->pd_tim->CCMR1 & 0x00FF) |
TIM_CCMR1_OC2M_1 | TIM_CCMR1_OC2M_2 |
TIM_CCMR1_OC2PE;
pwmp->pd_tim->SR = ~TIM_SR_CC2IF;
pwmp->pd_tim->DIER |= pwmp->pd_config->pc_channels[1].pcc_callback == NULL
? 0 : TIM_DIER_CC2IE;
break;
case 2:
pwmp->pd_tim->CCMR2 = (pwmp->pd_tim->CCMR2 & 0xFF00) |
TIM_CCMR2_OC3M_1 | TIM_CCMR2_OC3M_2 |
TIM_CCMR2_OC3PE;
pwmp->pd_tim->SR = ~TIM_SR_CC3IF;
pwmp->pd_tim->DIER |= pwmp->pd_config->pc_channels[2].pcc_callback == NULL
? 0 : TIM_DIER_CC3IE;
break;
case 3:
pwmp->pd_tim->CCMR2 = (pwmp->pd_tim->CCMR2 & 0x00FF) |
TIM_CCMR2_OC4M_1 | TIM_CCMR2_OC4M_2 |
TIM_CCMR2_OC4PE;
pwmp->pd_tim->SR = ~TIM_SR_CC4IF;
pwmp->pd_tim->DIER |= pwmp->pd_config->pc_channels[3].pcc_callback == NULL
? 0 : TIM_DIER_CC4IE;
break;
}
}
}
/**
* @brief Disables a PWM channel.
* @details The channel is disabled and its output line returned to the
* idle state.
*
* @param[in] pwmp pointer to a @p PWMDriver object
* @param[in] channel PWM channel identifier (0...PWM_CHANNELS-1])
*
* @notapi
*/
void pwm_lld_disable_channel(PWMDriver *pwmp, pwmchannel_t channel) {
pwmp->pd_enabled_channels &= ~(1 << channel);
switch (channel) {
case 0:
pwmp->pd_tim->CCR1 = 0;
pwmp->pd_tim->CCMR1 = pwmp->pd_tim->CCMR1 & 0xFF00;
pwmp->pd_tim->DIER &= ~TIM_DIER_CC1IE;
break;
case 1:
pwmp->pd_tim->CCR2 = 0;
pwmp->pd_tim->CCMR1 = pwmp->pd_tim->CCMR1 & 0x00FF;
pwmp->pd_tim->DIER &= ~TIM_DIER_CC2IE;
break;
case 2:
pwmp->pd_tim->CCR3 = 0;
pwmp->pd_tim->CCMR2 = pwmp->pd_tim->CCMR2 & 0xFF00;
pwmp->pd_tim->DIER &= ~TIM_DIER_CC3IE;
break;
case 3:
pwmp->pd_tim->CCR4 = 0;
pwmp->pd_tim->CCMR2 = pwmp->pd_tim->CCMR2 & 0x00FF;
pwmp->pd_tim->DIER &= ~TIM_DIER_CC4IE;
break;
}
}
#endif /* HAL_USE_PWM */
/** @} */
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