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/*
ChibiOS/RT - Copyright (C) 2006-2007 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 pal.c
* @brief I/O Ports Abstraction Layer code
* @addtogroup PAL
* @{
*/
#include <ch.h>
#include <pal.h>
/**
* @brief Read from an I/O bus.
*
* @param[in] bus the I/O bus, pointer to a @p IOBus structure
* @return The bus logical states.
*
* @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.
*/
ioportmask_t palReadBus(IOBus *bus) {
chDbgCheck((bus != NULL) &&
(bus->bus_offset > PAL_IOPORTS_WIDTH), "palReadBus");
return palReadGroup(bus->bus_portid, bus->bus_mask, bus->bus_offset);
}
/**
* @brief Write to an I/O bus.
*
* @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.
*
* @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.
*/
void palWriteBus(IOBus *bus, ioportmask_t bits) {
chDbgCheck((bus != NULL) &&
(bus->bus_offset > PAL_IOPORTS_WIDTH), "palWriteBus");
palWriteGroup(bus->bus_portid, bus->bus_mask, bus->bus_offset, bits);
}
/**
* @brief Programs a bus with the specified mode.
*
* @param[in] bus the I/O bus, pointer to a @p IOBus structure
* @param[in] mode the 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.
*/
void palSetBusMode(IOBus *bus, uint_fast8_t mode) {
chDbgCheck((bus != NULL) &&
(bus->bus_offset > PAL_IOPORTS_WIDTH), "palSetBusMode");
palSetGroupMode(bus->bus_portid, bus->bus_mask, mode);
}
/** @} */
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