diff options
| -rw-r--r-- | os/hal/platforms/AVR/i2c_lld.c | 293 | ||||
| -rw-r--r-- | os/hal/platforms/AVR/i2c_lld.h | 227 | ||||
| -rw-r--r-- | os/hal/platforms/AVR/platform.dox | 12 | ||||
| -rw-r--r-- | os/hal/platforms/AVR/platform.mk | 3 | ||||
| -rw-r--r-- | readme.txt | 1 |
5 files changed, 535 insertions, 1 deletions
diff --git a/os/hal/platforms/AVR/i2c_lld.c b/os/hal/platforms/AVR/i2c_lld.c new file mode 100644 index 000000000..4795031ba --- /dev/null +++ b/os/hal/platforms/AVR/i2c_lld.c @@ -0,0 +1,293 @@ +/*
+ 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 AVR/i2c_lld.c
+ * @brief AVR I2C subsystem low level driver source.
+ *
+ * @addtogroup I2C
+ * @{
+ */
+
+#include "ch.h"
+#include "hal.h"
+
+#if HAL_USE_I2C || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver local definitions. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/** @brief I2C driver identifier.*/
+#if USE_AVR_I2C || defined(__DOXYGEN__)
+I2CDriver I2CD;
+#endif
+
+/*===========================================================================*/
+/* Driver local variables. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Wakes up the waiting thread.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] msg wakeup message
+ *
+ * @notapi
+ */
+#define wakeup_isr(i2cp, msg) { \
+ chSysLockFromIsr(); \
+ if ((i2cp)->thread != NULL) { \
+ Thread *tp = (i2cp)->thread; \
+ (i2cp)->thread = NULL; \
+ tp->p_u.rdymsg = (msg); \
+ chSchReadyI(tp); \
+ } \
+ chSysUnlockFromIsr(); \
+}
+
+/*===========================================================================*/
+/* Driver interrupt handlers. */
+/*===========================================================================*/
+
+#if USE_AVR_I2C || defined(__DOXYGEN__)
+/**
+ * @brief I2C event interrupt handler.
+ *
+ * @notapi
+ */
+CH_IRQ_HANDLER(TWI_vect) {
+ CH_IRQ_PROLOGUE();
+
+ I2CDriver *i2cp = &I2CD;
+
+ switch (TWSR & 0xF8) {
+ case TWI_START:
+ case TWI_REPEAT_START:
+ TWDR = (i2cp->addr << 1);
+ if ((i2cp->txbuf == NULL) || (i2cp->txbytes == 0) || (i2cp->txidx == i2cp->txbytes)) {
+ TWDR |= 0x01;
+ }
+ TWCR = ((1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+ break;
+ case TWI_MASTER_TX_ADDR_ACK:
+ case TWI_MASTER_TX_DATA_ACK:
+ if (i2cp->txidx < i2cp->txbytes) {
+ TWDR = i2cp->txbuf[i2cp->txidx++];
+ TWCR = ((1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+ } else {
+ if (i2cp->rxbuf && i2cp->rxbytes) {
+ TWCR = ((1 << TWSTA) | (1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+ } else {
+ TWCR = ((1 << TWSTO) | (1 << TWINT) | (1 << TWEN));
+ wakeup_isr(i2cp, RDY_OK);
+ }
+ }
+ break;
+ case TWI_MASTER_RX_ADDR_ACK:
+ if (i2cp->rxidx == (i2cp->rxbytes - 1)) {
+ TWCR = ((1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+ } else {
+ TWCR = ((1 << TWEA) | (1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+ }
+ break;
+ case TWI_MASTER_RX_DATA_ACK:
+ i2cp->rxbuf[i2cp->rxidx++] = TWDR;
+ if (i2cp->rxidx == (i2cp->rxbytes - 1)) {
+ TWCR = ((1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+ } else {
+ TWCR = ((1 << TWEA) | (1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+ }
+ break;
+ case TWI_MASTER_RX_DATA_NACK:
+ i2cp->rxbuf[i2cp->rxidx] = TWDR;
+ TWCR = ((1 << TWSTO) | (1 << TWINT) | (1 << TWEN));
+ wakeup_isr(i2cp, RDY_OK);
+ case TWI_MASTER_TX_ADDR_NACK:
+ case TWI_MASTER_TX_DATA_NACK:
+ case TWI_MASTER_RX_ADDR_NACK:
+ i2cp->errors |= I2CD_ACK_FAILURE;
+ break;
+ case TWI_ARBITRATION_LOST:
+ i2cp->errors |= I2CD_ARBITRATION_LOST;
+ break;
+ case TWI_BUS_ERROR:
+ i2cp->errors |= I2CD_BUS_ERROR;
+ break;
+ default:
+ /* FIXME: only gets here if there are other MASTERs in the bus */
+ TWCR = ((1 << TWSTO) | (1 << TWINT) | (1 << TWEN));
+ wakeup_isr(i2cp, RDY_RESET);
+ }
+
+ if (i2cp->errors != I2CD_NO_ERROR) {
+ TWCR = ((1 << TWSTO) | (1 << TWINT) | (1 << TWEN));
+ wakeup_isr(i2cp, RDY_RESET);
+ }
+
+ CH_IRQ_EPILOGUE();
+}
+#endif /* USE_AVR_I2C */
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Low level I2C driver initialization.
+ *
+ * @notapi
+ */
+void i2c_lld_init(void) {
+ i2cObjectInit(&I2CD);
+}
+
+/**
+ * @brief Configures and activates the I2C peripheral.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+void i2c_lld_start(I2CDriver *i2cp) {
+
+ /* TODO: Test TWI without external pull-ups (use internal) */
+
+ /* Configure prescaler to 1 */
+ TWSR &= 0xF8;
+
+ /* Configure baudrate */
+ TWBR = ((F_CPU / i2cp->config->clock_speed) - 16) / 2;
+}
+
+/**
+ * @brief Deactivates the I2C peripheral.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+void i2c_lld_stop(I2CDriver *i2cp) {
+
+ if (i2cp->state != I2C_STOP) {
+ /* Disable TWI subsystem and stop all operations */
+ TWCR &= ~(1 << TWEN);
+ }
+}
+
+/**
+ * @brief Receives data via the I2C bus as master.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] addr slave device address
+ * @param[out] rxbuf pointer to the 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 RDY_OK if the function succeeded.
+ * @retval RDY_RESET if one or more I2C errors occurred, the errors can
+ * be retrieved using @p i2cGetErrors().
+ * @retval RDY_TIMEOUT if a timeout occurred before operation end. <b>After a
+ * timeout the driver must be stopped and restarted
+ * because the bus is in an uncertain state</b>.
+ *
+ * @notapi
+ */
+msg_t i2c_lld_master_receive_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout) {
+ i2cp->addr = addr;
+ i2cp->txbuf = NULL;
+ i2cp->txbytes = 0;
+ i2cp->txidx = 0;
+ i2cp->rxbuf = rxbuf;
+ i2cp->rxbytes = rxbytes;
+ i2cp->rxidx = 0;
+
+ /* Send START */
+ TWCR = ((1 << TWSTA) | (1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+
+ chSysLock();
+ i2cp->thread = chThdSelf();
+ chSchGoSleepS(THD_STATE_SUSPENDED);
+ chSysUnlock();
+
+ return chThdSelf()->p_u.rdymsg;
+}
+
+/**
+ * @brief Transmits data via the I2C bus as master.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] addr slave device address
+ * @param[in] txbuf pointer to the transmit buffer
+ * @param[in] txbytes number of bytes to be transmitted
+ * @param[out] rxbuf pointer to the 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 RDY_OK if the function succeeded.
+ * @retval RDY_RESET if one or more I2C errors occurred, the errors can
+ * be retrieved using @p i2cGetErrors().
+ * @retval RDY_TIMEOUT if a timeout occurred before operation end. <b>After a
+ * timeout the driver must be stopped and restarted
+ * because the bus is in an uncertain state</b>.
+ *
+ * @notapi
+ */
+msg_t i2c_lld_master_transmit_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ const uint8_t *txbuf, size_t txbytes,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout) {
+ i2cp->addr = addr;
+ i2cp->txbuf = txbuf;
+ i2cp->txbytes = txbytes;
+ i2cp->txidx = 0;
+ i2cp->rxbuf = rxbuf;
+ i2cp->rxbytes = rxbytes;
+ i2cp->rxidx = 0;
+
+ TWCR = ((1 << TWSTA) | (1 << TWINT) | (1 << TWEN) | (1 << TWIE));
+
+ chSysLock();
+ i2cp->thread = chThdSelf();
+ chSchGoSleepS(THD_STATE_SUSPENDED);
+ chSysUnlock();
+
+ return chThdSelf()->p_u.rdymsg;
+}
+
+#endif /* HAL_USE_I2C */
+
+/** @} */
diff --git a/os/hal/platforms/AVR/i2c_lld.h b/os/hal/platforms/AVR/i2c_lld.h new file mode 100644 index 000000000..6fae3b67f --- /dev/null +++ b/os/hal/platforms/AVR/i2c_lld.h @@ -0,0 +1,227 @@ +/*
+ 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 AVR/i2c_lld.h
+ * @brief AVR I2C subsystem low level driver header.
+ *
+ * @addtogroup I2C
+ * @{
+ */
+
+#ifndef _I2C_LLD_H_
+#define _I2C_LLD_H_
+
+#if HAL_USE_I2C || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver constants. */
+/*===========================================================================*/
+
+/** START transmitted */
+#define TWI_START 0x08
+/** Repeated START transmitted */
+#define TWI_REPEAT_START 0x10
+/** Arbitration Lost */
+#define TWI_ARBITRATION_LOST 0x38
+/** Bus errors */
+#define TWI_BUS_ERROR 0x00
+
+/** SLA+W transmitted with ACK response */
+#define TWI_MASTER_TX_ADDR_ACK 0x18
+/** SLA+W transmitted with NACK response */
+#define TWI_MASTER_TX_ADDR_NACK 0x20
+/** DATA transmitted with ACK response */
+#define TWI_MASTER_TX_DATA_ACK 0x28
+/** DATA transmitted with NACK response */
+#define TWI_MASTER_TX_DATA_NACK 0x30
+
+/** SLA+R transmitted with ACK response */
+#define TWI_MASTER_RX_ADDR_ACK 0x40
+/** SLA+R transmitted with NACK response */
+#define TWI_MASTER_RX_ADDR_NACK 0x48
+/** DATA received with ACK response */
+#define TWI_MASTER_RX_DATA_ACK 0x50
+/** DATA received with NACK response */
+#define TWI_MASTER_RX_DATA_NACK 0x58
+
+/*===========================================================================*/
+/* Driver pre-compile time settings. */
+/*===========================================================================*/
+
+/**
+ * @name Configuration options
+ * @{
+ */
+/**
+ * @brief I2C driver enable switch.
+ * @details If set to @p TRUE the support for I2C is included.
+ * @note The default is @p FALSE.
+ */
+#if !defined(USE_AVR_I2C) || defined(__DOXYGEN__)
+#define USE_AVR_I2C FALSE
+#endif
+
+/*===========================================================================*/
+/* Derived constants and error checks. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver data structures and types. */
+/*===========================================================================*/
+
+/**
+ * @brief Type representing I2C address.
+ */
+typedef uint8_t i2caddr_t;
+
+/**
+ * @brief I2C Driver condition flags type.
+ */
+typedef uint8_t i2cflags_t;
+
+/**
+ * @brief Driver configuration structure.
+ * @note Implementations may extend this structure to contain more,
+ * architecture dependent, fields.
+ */
+typedef struct {
+
+ /**
+ * @brief Specifies the I2C clock frequency.
+ */
+ uint32_t clock_speed;
+
+} I2CConfig;
+
+/**
+ * @brief Structure representing an I2C driver.
+ */
+struct I2CDriver {
+ /**
+ * @brief Driver state.
+ */
+ i2cstate_t state;
+ /**
+ * @brief Current configuration data.
+ */
+ const I2CConfig *config;
+ /**
+ * @brief Error flags.
+ */
+ i2cflags_t errors;
+#if I2C_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__)
+#if CH_USE_MUTEXES || defined(__DOXYGEN__)
+ /**
+ * @brief Mutex protecting the bus.
+ */
+ Mutex mutex;
+#elif CH_USE_SEMAPHORES
+ Semaphore semaphore;
+#endif
+#endif /* I2C_USE_MUTUAL_EXCLUSION */
+#if defined(I2C_DRIVER_EXT_FIELDS)
+ I2C_DRIVER_EXT_FIELDS
+#endif
+ /* End of the mandatory fields.*/
+ /**
+ * @brief Thread waiting for I/O completion.
+ */
+ Thread *thread;
+ /**
+ * @brief Address of slave device
+ */
+ i2caddr_t addr;
+ /**
+ * @brief Pointer to the buffer with data to send.
+ */
+ const uint8_t *txbuf;
+ /**
+ * @brief Number of bytes of data to send.
+ */
+ size_t txbytes;
+ /**
+ * @brief Current index in buffer when sending data.
+ */
+ size_t txidx;
+ /**
+ * @brief Pointer to the buffer to put received data.
+ */
+ uint8_t *rxbuf;
+ /**
+ * @brief Number of bytes of data to receive.
+ */
+ size_t rxbytes;
+ /**
+ * @brief Current index in buffer when receiving data.
+ */
+ size_t rxidx;
+};
+
+/**
+ * @brief Type of a structure representing an I2C driver.
+ */
+typedef struct I2CDriver I2CDriver;
+
+/*===========================================================================*/
+/* Driver macros. */
+/*===========================================================================*/
+
+/**
+ * @brief Get errors from I2C driver.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+#define i2c_lld_get_errors(i2cp) ((i2cp)->errors)
+
+/*===========================================================================*/
+/* External declarations. */
+/*===========================================================================*/
+
+#if !defined(__DOXYGEN__)
+#if USE_AVR_I2C
+extern I2CDriver I2CD;
+#endif
+#endif /* !defined(__DOXYGEN__) */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+ void i2c_lld_init(void);
+ void i2c_lld_start(I2CDriver *i2cp);
+ void i2c_lld_stop(I2CDriver *i2cp);
+ msg_t i2c_lld_master_transmit_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ const uint8_t *txbuf, size_t txbytes,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout);
+ msg_t i2c_lld_master_receive_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* HAL_USE_I2C */
+
+#endif /* _I2C_LLD_H_ */
+
+/** @} */
diff --git a/os/hal/platforms/AVR/platform.dox b/os/hal/platforms/AVR/platform.dox index c80e61c2e..a9bb09c04 100644 --- a/os/hal/platforms/AVR/platform.dox +++ b/os/hal/platforms/AVR/platform.dox @@ -100,3 +100,15 @@ * .
* @ingroup AVR_DRIVERS
*/
+
+/**
+ * @defgroup AVR_I2C AVR I2C Support
+ * @details The AVR I2C driver uses the TWI peripheral in an interrupt
+ * driven, implementation.
+ *
+ * @section avr_i2c Supported HW resources
+ * The i2c driver can support the following hardware resource:
+ * - I2C.
+ * .
+ * @ingroup AVR_DRIVERS
+ */
diff --git a/os/hal/platforms/AVR/platform.mk b/os/hal/platforms/AVR/platform.mk index e31413c79..86a2c2eba 100644 --- a/os/hal/platforms/AVR/platform.mk +++ b/os/hal/platforms/AVR/platform.mk @@ -1,7 +1,8 @@ # List of all the AVR platform files.
PLATFORMSRC = ${CHIBIOS}/os/hal/platforms/AVR/hal_lld.c \
${CHIBIOS}/os/hal/platforms/AVR/pal_lld.c \
- ${CHIBIOS}/os/hal/platforms/AVR/serial_lld.c
+ ${CHIBIOS}/os/hal/platforms/AVR/serial_lld.c \
+ ${CHIBIOS}/os/hal/platforms/AVR/i2c_lld.c
# Required include directories
PLATFORMINC = ${CHIBIOS}/os/hal/platforms/AVR
diff --git a/readme.txt b/readme.txt index c9a2e8f17..25ab67dbe 100644 --- a/readme.txt +++ b/readme.txt @@ -163,6 +163,7 @@ to 2.4.1).
- NEW: Added demo for Arduino Mega, contributed by Fabio Utzig.
- NEW: Added support for ATmega1280, contributed by Fabio Utzig.
+- NEW: Added I2C driver for AVR, contributed by Fabio Utzig.
- NEW: Added FatFs demo for the Olimex STM32-P107 board.
- NEW: Added support for the Olimex STM32-E407 board. Added an integrated
demo including USB-CDC, lwIP with web server, FatFs and shell, all running
|