ChibiOS/os/hal/platforms/STM32F0xx/serial_lld.c

323 lines
8.4 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 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/serial_lld.c
* @brief STM32 low level serial driver code.
*
* @addtogroup SERIAL
* @{
*/
#include "ch.h"
#include "hal.h"
#if HAL_USE_SERIAL || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/** @brief USART1 serial driver identifier.*/
#if STM32_SERIAL_USE_USART1 || defined(__DOXYGEN__)
SerialDriver SD1;
#endif
/** @brief USART2 serial driver identifier.*/
#if STM32_SERIAL_USE_USART2 || defined(__DOXYGEN__)
SerialDriver SD2;
#endif
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/** @brief Driver default configuration.*/
static const SerialConfig default_config =
{
SERIAL_DEFAULT_BITRATE,
0,
USART_CR2_STOP1_BITS | USART_CR2_LINEN,
0
};
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/**
* @brief USART initialization.
* @details This function must be invoked with interrupts disabled.
*
* @param[in] sdp pointer to a @p SerialDriver object
* @param[in] config the architecture-dependent serial driver configuration
*/
static void usart_init(SerialDriver *sdp, const SerialConfig *config) {
USART_TypeDef *u = sdp->usart;
/*
* Baud rate setting.
*/
if (sdp->usart == USART1)
u->BRR = STM32_USART1CLK / config->sc_speed;
else
u->BRR = STM32_PCLK / config->sc_speed;
/*
* Note that some bits are enforced.
*/
u->CR1 = config->sc_cr1 | USART_CR1_UE | USART_CR1_PEIE |
USART_CR1_RXNEIE | USART_CR1_TE |
USART_CR1_RE;
u->CR2 = config->sc_cr2 | USART_CR2_LBDIE;
u->CR3 = config->sc_cr3 | USART_CR3_EIE;
u->ICR = 0xFFFFFFFF;
}
/**
* @brief USART de-initialization.
* @details This function must be invoked with interrupts disabled.
*
* @param[in] u pointer to an USART I/O block
*/
static void usart_deinit(USART_TypeDef *u) {
u->CR1 = 0;
u->CR2 = 0;
u->CR3 = 0;
}
#if STM32_SERIAL_USE_USART1 || STM32_SERIAL_USE_USART2
/**
* @brief Error handling routine.
*
* @param[in] sdp pointer to a @p SerialDriver object
* @param[in] isr USART ISR register value
*/
static void set_error(SerialDriver *sdp, uint16_t isr) {
chnflags_t sts = 0;
if (isr & USART_ISR_ORE)
sts |= SD_OVERRUN_ERROR;
if (isr & USART_ISR_PE)
sts |= SD_PARITY_ERROR;
if (isr & USART_ISR_FE)
sts |= SD_FRAMING_ERROR;
if (isr & USART_ISR_NE)
sts |= SD_NOISE_ERROR;
chSysLockFromIsr();
chnAddFlagsI(sdp, sts);
chSysUnlockFromIsr();
}
/**
* @brief Common IRQ handler.
*
* @param[in] sdp communication channel associated to the USART
*/
static void serve_interrupt(SerialDriver *sdp) {
USART_TypeDef *u = sdp->usart;
uint16_t cr1 = u->CR1;
uint16_t isr;
/* Reading and clearing status.*/
isr = u->ISR;
u->ICR = isr;
/* Error condition detection.*/
if (isr & (USART_ISR_ORE | USART_ISR_NE | USART_ISR_FE | USART_ISR_PE))
set_error(sdp, isr);
/* Special case, LIN break detection.*/
if (isr & USART_ISR_LBD) {
chSysLockFromIsr();
chnAddFlagsI(sdp, SD_BREAK_DETECTED);
chSysUnlockFromIsr();
}
/* Data available.*/
if (isr & USART_ISR_RXNE) {
chSysLockFromIsr();
sdIncomingDataI(sdp, (uint8_t)u->RDR);
chSysUnlockFromIsr();
}
/* Transmission buffer empty.*/
if ((cr1 & USART_CR1_TXEIE) && (isr & USART_ISR_TXE)) {
msg_t b;
chSysLockFromIsr();
b = chOQGetI(&sdp->oqueue);
if (b < Q_OK) {
chnAddFlagsI(sdp, CHN_OUTPUT_EMPTY);
u->CR1 = (cr1 & ~USART_CR1_TXEIE) | USART_CR1_TCIE;
}
else
u->TDR = b;
chSysUnlockFromIsr();
}
/* Physical transmission end.*/
if (isr & USART_ISR_TC) {
chSysLockFromIsr();
chnAddFlagsI(sdp, CHN_TRANSMISSION_END);
chSysUnlockFromIsr();
u->CR1 = cr1 & ~USART_CR1_TCIE;
}
}
#endif
#if STM32_SERIAL_USE_USART1 || defined(__DOXYGEN__)
static void notify1(GenericQueue *qp) {
(void)qp;
USART1->CR1 |= USART_CR1_TXEIE;
}
#endif
#if STM32_SERIAL_USE_USART2 || defined(__DOXYGEN__)
static void notify2(GenericQueue *qp) {
(void)qp;
USART2->CR1 |= USART_CR1_TXEIE;
}
#endif
/*===========================================================================*/
/* Driver interrupt handlers. */
/*===========================================================================*/
#if STM32_SERIAL_USE_USART1 || defined(__DOXYGEN__)
/**
* @brief USART1 interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(USART1_IRQHandler) {
CH_IRQ_PROLOGUE();
serve_interrupt(&SD1);
CH_IRQ_EPILOGUE();
}
#endif
#if STM32_SERIAL_USE_USART2 || defined(__DOXYGEN__)
/**
* @brief USART2 interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(USART2_IRQHandler) {
CH_IRQ_PROLOGUE();
serve_interrupt(&SD2);
CH_IRQ_EPILOGUE();
}
#endif
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level serial driver initialization.
*
* @notapi
*/
void sd_lld_init(void) {
#if STM32_SERIAL_USE_USART1
sdObjectInit(&SD1, NULL, notify1);
SD1.usart = USART1;
#endif
#if STM32_SERIAL_USE_USART2
sdObjectInit(&SD2, NULL, notify2);
SD2.usart = USART2;
#endif
}
/**
* @brief Low level serial driver configuration and (re)start.
*
* @param[in] sdp pointer to a @p SerialDriver object
* @param[in] config the architecture-dependent serial driver configuration.
* If this parameter is set to @p NULL then a default
* configuration is used.
*
* @notapi
*/
void sd_lld_start(SerialDriver *sdp, const SerialConfig *config) {
if (config == NULL)
config = &default_config;
if (sdp->state == SD_STOP) {
#if STM32_SERIAL_USE_USART1
if (&SD1 == sdp) {
rccEnableUSART1(FALSE);
nvicEnableVector(USART1_IRQn,
CORTEX_PRIORITY_MASK(STM32_SERIAL_USART1_PRIORITY));
}
#endif
#if STM32_SERIAL_USE_USART2
if (&SD2 == sdp) {
rccEnableUSART2(FALSE);
nvicEnableVector(USART2_IRQn,
CORTEX_PRIORITY_MASK(STM32_SERIAL_USART2_PRIORITY));
}
#endif
}
usart_init(sdp, config);
}
/**
* @brief Low level serial driver stop.
* @details De-initializes the USART, stops the associated clock, resets the
* interrupt vector.
*
* @param[in] sdp pointer to a @p SerialDriver object
*
* @notapi
*/
void sd_lld_stop(SerialDriver *sdp) {
if (sdp->state == SD_READY) {
usart_deinit(sdp->usart);
#if STM32_SERIAL_USE_USART1
if (&SD1 == sdp) {
rccDisableUSART1(FALSE);
nvicDisableVector(USART1_IRQn);
return;
}
#endif
#if STM32_SERIAL_USE_USART2
if (&SD2 == sdp) {
rccDisableUSART2(FALSE);
nvicDisableVector(USART2_IRQn);
return;
}
#endif
}
}
#endif /* HAL_USE_SERIAL */
/** @} */