tinySA/os/hal/src/pal.c

123 lines
4.8 KiB
C

/*
ChibiOS - Copyright (C) 2006..2015 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 pal.c
* @brief I/O Ports Abstraction Layer code.
*
* @addtogroup PAL
* @{
*/
#include "hal.h"
#if (HAL_USE_PAL == TRUE) || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver local definitions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables and types. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Read from an I/O bus.
* @note The operation is not guaranteed to be atomic on all the
* architectures, for atomicity and/or portability reasons you may
* need to enclose port I/O operations between @p chSysLock() and
* @p chSysUnlock().
* @note The function internally uses the @p palReadGroup() macro. The use
* of this function is preferred when you value code size, readability
* and error checking over speed.
* @note The function can be called from any context.
*
* @param[in] bus the I/O bus, pointer to a @p IOBus structure
* @return The bus logical states.
*
* @special
*/
ioportmask_t palReadBus(IOBus *bus) {
osalDbgCheck((bus != NULL) && (bus->offset < PAL_IOPORTS_WIDTH));
return palReadGroup(bus->portid, bus->mask, bus->offset);
}
/**
* @brief Write to an I/O bus.
* @note The operation is not guaranteed to be atomic on all the
* architectures, for atomicity and/or portability reasons you may
* need to enclose port I/O operations between @p chSysLock() and
* @p chSysUnlock().
* @note The default implementation is non atomic and not necessarily
* optimal. Low level drivers may optimize the function by using
* specific hardware or coding.
* @note The function can be called from any context.
*
* @param[in] bus the I/O bus, pointer to a @p IOBus structure
* @param[in] bits the bits to be written on the I/O bus. Values exceeding
* the bus width are masked so most significant bits are
* lost.
*
* @special
*/
void palWriteBus(IOBus *bus, ioportmask_t bits) {
osalDbgCheck((bus != NULL) && (bus->offset < PAL_IOPORTS_WIDTH));
palWriteGroup(bus->portid, bus->mask, bus->offset, bits);
}
/**
* @brief Programs a bus with the specified mode.
* @note The operation is not guaranteed to be atomic on all the
* architectures, for atomicity and/or portability reasons you may
* need to enclose port I/O operations between @p chSysLock() and
* @p chSysUnlock().
* @note The default implementation is non atomic and not necessarily
* optimal. Low level drivers may optimize the function by using
* specific hardware or coding.
* @note The function can be called from any context.
*
* @param[in] bus the I/O bus, pointer to a @p IOBus structure
* @param[in] mode the mode
*
* @special
*/
void palSetBusMode(IOBus *bus, iomode_t mode) {
osalDbgCheck((bus != NULL) && (bus->offset < PAL_IOPORTS_WIDTH));
palSetGroupMode(bus->portid, bus->mask, bus->offset, mode);
}
#endif /* HAL_USE_PAL == TRUE */
/** @} */