ChibiOS/os/hal/platforms/STM8L/serial_lld.c

/*
    ChibiOS/RT - Copyright (C) 2006-2013 Giovanni Di Sirio

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/

/**
 * @file    STM8L/serial_lld.c
 * @brief   STM8L 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 STM8L_SERIAL_USE_USART1 || defined(__DOXYGEN__)
SerialDriver SD1;
#endif

/**
 * @brief   USART2 serial driver identifier.
 */
#if STM8L_SERIAL_USE_USART2 || defined(__DOXYGEN__)
SerialDriver SD2;
#endif

/**
 * @brief   USART3 serial driver identifier.
 */
#if STM8L_SERIAL_USE_USART3 || defined(__DOXYGEN__)
SerialDriver SD3;
#endif

/*===========================================================================*/
/* Driver local variables and types.                                         */
/*===========================================================================*/

/**
 * @brief   Driver default configuration.
 */
static ROMCONST SerialConfig default_config = {
  BRR(SERIAL_DEFAULT_BITRATE),
  SD_MODE_PARITY_NONE | SD_MODE_STOP_1
};

/*===========================================================================*/
/* Driver local functions.                                                   */
/*===========================================================================*/

#if STM8L_SERIAL_USE_USART1 || defined(__DOXYGEN__)
static void notify1(GenericQueue *qp) {

  (void)qp;
  USART1->CR2 |= USART_CR2_TIEN;
}
#endif /* STM8L_SERIAL_USE_USART1 */

#if STM8L_SERIAL_USE_USART2 || defined(__DOXYGEN__)
static void notify2(GenericQueue *qp) {

  (void)qp;
  USART2->CR2 |= USART_CR2_TIEN;
}
#endif /* STM8L_SERIAL_USE_USART1 */

#if STM8L_SERIAL_USE_USART3 || defined(__DOXYGEN__)
static void notify3(GenericQueue *qp) {

  (void)qp;
  USART3->CR2 |= USART_CR2_TIEN;
}
#endif /* STM8L_SERIAL_USE_USART3 */

/*===========================================================================*/
/* Driver interrupt handlers.                                                */
/*===========================================================================*/

/* See in serial_lld.h.*/

/*===========================================================================*/
/* Driver exported functions.                                                */
/*===========================================================================*/

/**
 * @brief   Error handling routine.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 * @param[in] sr        USART SR register value
 *
 * @notapi
 */
void sd_lld_set_error(SerialDriver *sdp, uint8_t sr) {
  flagsmask_t sts = 0;

  if (sr & USART_SR_OR)
    sts |= SD_OVERRUN_ERROR;
  if (sr & USART_SR_NF)
    sts |= SD_NOISE_ERROR;
  if (sr & USART_SR_FE)
    sts |= SD_FRAMING_ERROR;
  if (sr & USART_SR_PE)
    sts |= SD_PARITY_ERROR;
  chSysLockFromIsr();
  chnAddFlagsI(sdp, sts);
  chSysUnlockFromIsr();
}

/**
 * @brief   Low level serial driver initialization.
 *
 * @notapi
 */
void sd_lld_init(void) {

#if STM8L_SERIAL_USE_USART1
  sdObjectInit(&SD1, NULL, notify1);
  CLK->PCKENR1 |= CLK_PCKENR1_USART1;       /* PCKEN12, clock source.       */
  USART1->CR1 = USART_CR1_USARTD;           /* USARTD (low power).          */
  SD1.usart = USART1;
#endif

#if STM8L_SERIAL_USE_USART2
  sdObjectInit(&SD2, NULL, notify2);
  CLK->PCKENR3 |= CLK_PCKENR3_USART2;       /* PCKEN13, clock source.       */
  USART2->CR1 = USART_CR1_USARTD;           /* USARTD (low power).          */
  SD2.usart = USART2;
#endif

#if STM8L_SERIAL_USE_USART3
  sdObjectInit(&SD3, NULL, notify3);
  CLK->PCKENR3 |= CLK_PCKENR3_USART3;       /* PCKEN13, clock source.       */
  USART3->CR1 = USART_CR1_USARTD;           /* USARTD (low power).          */
  SD3.usart = USART3;
#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) {
  USART_TypeDef *u = sdp->usart;

  if (config == NULL)
    config = &default_config;

  u->BRR2 = (uint8_t)(((uint8_t)(config->sc_brr >> 8) & (uint8_t)0xF0) |
                      ((uint8_t)config->sc_brr & (uint8_t)0x0F));
  u->BRR1 = (uint8_t)(config->sc_brr >> 4);
  u->CR1  = (uint8_t)(config->sc_mode & SD_MODE_PARITY);
  u->CR2  = USART_CR2_RIEN | USART_CR2_TEN | USART_CR2_REN;
  u->CR3  = (uint8_t)(config->sc_mode & SD_MODE_STOP);
  u->CR4  = 0;
  u->CR5  = 0;
  u->PSCR = 1;
  (void)u->SR;
  (void)u->DR;
}

/**
 * @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) {
  USART_TypeDef *u = sdp->usart;

  u->CR1  = USART_CR1_USARTD;
  u->CR2  = 0;
  u->CR3  = 0;
  u->CR4  = 0;
  u->CR5  = 0;
  u->PSCR = 0;
}

#endif /* HAL_USE_SERIAL */

/** @} */