From dbd493cff1bb0c9b0bdd3eeb081a56dbaa0235a8 Mon Sep 17 00:00:00 2001 From: gdisirio Date: Sat, 17 Aug 2013 15:32:41 +0000 Subject: I2C ported but needs to be reviewed to not use virtual timers directly. git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/kernel_3_dev@6170 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- os/hal/src/i2c.c | 283 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 283 insertions(+) create mode 100644 os/hal/src/i2c.c (limited to 'os/hal/src') diff --git a/os/hal/src/i2c.c b/os/hal/src/i2c.c new file mode 100644 index 000000000..3e037332b --- /dev/null +++ b/os/hal/src/i2c.c @@ -0,0 +1,283 @@ +/* + ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010, + 2011,2012,2013 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 . +*/ +/* + Concepts and parts of this file have been contributed by Uladzimir Pylinsky + aka barthess. + */ + +/** + * @file i2c.c + * @brief I2C Driver code. + * + * @addtogroup I2C + * @{ + */ +#include "hal.h" + +#if HAL_USE_I2C || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Driver local definitions. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver exported variables. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver local variables and types. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver local functions. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver exported functions. */ +/*===========================================================================*/ + +/** + * @brief I2C Driver initialization. + * @note This function is implicitly invoked by @p halInit(), there is + * no need to explicitly initialize the driver. + * + * @init + */ +void i2cInit(void) { + + i2c_lld_init(); +} + +/** + * @brief Initializes the standard part of a @p I2CDriver structure. + * + * @param[out] i2cp pointer to the @p I2CDriver object + * + * @init + */ +void i2cObjectInit(I2CDriver *i2cp) { + + i2cp->state = I2C_STOP; + i2cp->config = NULL; + +#if I2C_USE_MUTUAL_EXCLUSION + osalMutexObjectInit(&i2cp->mutex); +#endif /* I2C_USE_MUTUAL_EXCLUSION */ + +#if defined(I2C_DRIVER_EXT_INIT_HOOK) + I2C_DRIVER_EXT_INIT_HOOK(i2cp); +#endif +} + +/** + * @brief Configures and activates the I2C peripheral. + * + * @param[in] i2cp pointer to the @p I2CDriver object + * @param[in] config pointer to the @p I2CConfig object + * + * @api + */ +void i2cStart(I2CDriver *i2cp, const I2CConfig *config) { + + osalDbgCheck((i2cp != NULL) && (config != NULL)); + osalDbgAssert((i2cp->state == I2C_STOP) || (i2cp->state == I2C_READY) || + (i2cp->state == I2C_LOCKED), "invalid state"); + + osalSysLock(); + i2cp->config = config; + i2c_lld_start(i2cp); + i2cp->state = I2C_READY; + osalSysUnlock(); +} + +/** + * @brief Deactivates the I2C peripheral. + * + * @param[in] i2cp pointer to the @p I2CDriver object + * + * @api + */ +void i2cStop(I2CDriver *i2cp) { + + osalDbgCheck(i2cp != NULL); + osalDbgAssert((i2cp->state == I2C_STOP) || (i2cp->state == I2C_READY) || + (i2cp->state == I2C_LOCKED), "invalid state"); + + osalSysLock(); + i2c_lld_stop(i2cp); + i2cp->state = I2C_STOP; + osalSysUnlock(); +} + +/** + * @brief Returns the errors mask associated to the previous operation. + * + * @param[in] i2cp pointer to the @p I2CDriver object + * @return The errors mask. + * + * @api + */ +i2cflags_t i2cGetErrors(I2CDriver *i2cp) { + + osalDbgCheck(i2cp != NULL); + + return i2c_lld_get_errors(i2cp); +} + +/** + * @brief Sends data via the I2C bus. + * @details Function designed to realize "read-through-write" transfer + * paradigm. If you want transmit data without any further read, + * than set @b rxbytes field to 0. + * + * @param[in] i2cp pointer to the @p I2CDriver object + * @param[in] addr slave device address (7 bits) without R/W bit + * @param[in] txbuf pointer to transmit buffer + * @param[in] txbytes number of bytes to be transmitted + * @param[out] rxbuf pointer to receive buffer + * @param[in] rxbytes number of bytes to be received, set it to 0 if + * you want transmit only + * @param[in] timeout the number of ticks before the operation timeouts, + * the following special values are allowed: + * - @a TIME_INFINITE no timeout. + * . + * + * @return The operation status. + * @retval MSG_OK if the function succeeded. + * @retval MSG_RESET if one or more I2C errors occurred, the errors can + * be retrieved using @p i2cGetErrors(). + * @retval MSG_TIMEOUT if a timeout occurred before operation end. + * + * @api + */ +msg_t i2cMasterTransmitTimeout(I2CDriver *i2cp, + i2caddr_t addr, + const uint8_t *txbuf, + size_t txbytes, + uint8_t *rxbuf, + size_t rxbytes, + systime_t timeout) { + msg_t rdymsg; + + osalDbgCheck((i2cp != NULL) && (addr != 0) && + (txbytes > 0) && (txbuf != NULL) && + ((rxbytes == 0) || ((rxbytes > 0) && (rxbuf != NULL))) && + (timeout != TIME_IMMEDIATE)); + + osalDbgAssert(i2cp->state == I2C_READY, "not ready"); + + osalSysLock(); + i2cp->errors = I2C_NO_ERROR; + i2cp->state = I2C_ACTIVE_TX; + rdymsg = i2c_lld_master_transmit_timeout(i2cp, addr, txbuf, txbytes, + rxbuf, rxbytes, timeout); + if (rdymsg == MSG_TIMEOUT) + i2cp->state = I2C_LOCKED; + else + i2cp->state = I2C_READY; + osalSysUnlock(); + return rdymsg; +} + +/** + * @brief Receives data from the I2C bus. + * + * @param[in] i2cp pointer to the @p I2CDriver object + * @param[in] addr slave device address (7 bits) without R/W bit + * @param[out] rxbuf pointer to receive buffer + * @param[in] rxbytes number of bytes to be received + * @param[in] timeout the number of ticks before the operation timeouts, + * the following special values are allowed: + * - @a TIME_INFINITE no timeout. + * . + * + * @return The operation status. + * @retval MSG_OK if the function succeeded. + * @retval MSG_RESET if one or more I2C errors occurred, the errors can + * be retrieved using @p i2cGetErrors(). + * @retval MSG_TIMEOUT if a timeout occurred before operation end. + * + * @api + */ +msg_t i2cMasterReceiveTimeout(I2CDriver *i2cp, + i2caddr_t addr, + uint8_t *rxbuf, + size_t rxbytes, + systime_t timeout){ + + msg_t rdymsg; + + osalDbgCheck((i2cp != NULL) && (addr != 0) && + (rxbytes > 0) && (rxbuf != NULL) && + (timeout != TIME_IMMEDIATE)); + + osalDbgAssert(i2cp->state == I2C_READY, "not ready"); + + osalSysLock(); + i2cp->errors = I2C_NO_ERROR; + i2cp->state = I2C_ACTIVE_RX; + rdymsg = i2c_lld_master_receive_timeout(i2cp, addr, rxbuf, rxbytes, timeout); + if (rdymsg == MSG_TIMEOUT) + i2cp->state = I2C_LOCKED; + else + i2cp->state = I2C_READY; + osalSysUnlock(); + return rdymsg; +} + +#if I2C_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__) +/** + * @brief Gains exclusive access to the I2C bus. + * @details This function tries to gain ownership to the SPI bus, if the bus + * is already being used then the invoking thread is queued. + * @pre In order to use this function the option @p I2C_USE_MUTUAL_EXCLUSION + * must be enabled. + * + * @param[in] i2cp pointer to the @p I2CDriver object + * + * @api + */ +void i2cAcquireBus(I2CDriver *i2cp) { + + osalDbgCheck(i2cp != NULL); + + osalMutexLock(&i2cp->mutex); +} + +/** + * @brief Releases exclusive access to the I2C bus. + * @pre In order to use this function the option @p I2C_USE_MUTUAL_EXCLUSION + * must be enabled. + * + * @param[in] i2cp pointer to the @p I2CDriver object + * + * @api + */ +void i2cReleaseBus(I2CDriver *i2cp) { + + osalDbgCheck(i2cp != NULL); + + osalMutexUnlock(&i2cp->mutex); +} +#endif /* I2C_USE_MUTUAL_EXCLUSION */ + +#endif /* HAL_USE_I2C */ + +/** @} */ -- cgit v1.2.3