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LibrePilot/flight/pios/stm32f4xx/pios_i2c.c
Alessio Morale 805750050c REVONANO - Support distinct remaps for SDA and SCL
2015-05-18 18:54:52 +02:00

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/**
******************************************************************************
* @addtogroup PIOS PIOS Core hardware abstraction layer
* @{
* @addtogroup PIOS_I2C I2C Functions
* @brief STM32F4xx Hardware dependent I2C functionality
* @{
*
* @file pios_i2c.c
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2012.
* @brief I2C Enable/Disable routines
* @see The GNU Public License (GPL) Version 3
*
*****************************************************************************/
/*
* This program 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.
*
* This program 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, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* @note This is very closely related to the F1xx code and should really
* be merged.
*/
#include "pios.h"
#ifdef PIOS_INCLUDE_I2C
#ifdef PIOS_INCLUDE_FREERTOS
#define USE_FREERTOS
#endif
#include <pios_i2c_priv.h>
enum i2c_adapter_state {
I2C_STATE_FSM_FAULT = 0, /* Must be zero so undefined transitions land here */
I2C_STATE_BUS_ERROR,
I2C_STATE_STOPPED,
I2C_STATE_STOPPING,
I2C_STATE_STARTING,
I2C_STATE_R_MORE_TXN_ADDR,
I2C_STATE_R_MORE_TXN_PRE_ONE,
I2C_STATE_R_MORE_TXN_PRE_FIRST,
I2C_STATE_R_MORE_TXN_PRE_MIDDLE,
I2C_STATE_R_MORE_TXN_PRE_LAST,
I2C_STATE_R_MORE_TXN_POST_LAST,
I2C_STATE_R_LAST_TXN_ADDR,
I2C_STATE_R_LAST_TXN_PRE_ONE,
I2C_STATE_R_LAST_TXN_PRE_FIRST,
I2C_STATE_R_LAST_TXN_PRE_MIDDLE,
I2C_STATE_R_LAST_TXN_PRE_LAST,
I2C_STATE_R_LAST_TXN_POST_LAST,
I2C_STATE_W_MORE_TXN_ADDR,
I2C_STATE_W_MORE_TXN_MIDDLE,
I2C_STATE_W_MORE_TXN_LAST,
I2C_STATE_W_LAST_TXN_ADDR,
I2C_STATE_W_LAST_TXN_MIDDLE,
I2C_STATE_W_LAST_TXN_LAST,
I2C_STATE_NACK,
I2C_STATE_NUM_STATES /* Must be last */
};
// #define I2C_HALT_ON_ERRORS
enum i2c_adapter_event {
I2C_EVENT_BUS_ERROR,
I2C_EVENT_START,
I2C_EVENT_STARTED_MORE_TXN_READ,
I2C_EVENT_STARTED_MORE_TXN_WRITE,
I2C_EVENT_STARTED_LAST_TXN_READ,
I2C_EVENT_STARTED_LAST_TXN_WRITE,
I2C_EVENT_ADDR_SENT_LEN_EQ_0,
I2C_EVENT_ADDR_SENT_LEN_EQ_1,
I2C_EVENT_ADDR_SENT_LEN_EQ_2,
I2C_EVENT_ADDR_SENT_LEN_GT_2,
I2C_EVENT_TRANSFER_DONE_LEN_EQ_0,
I2C_EVENT_TRANSFER_DONE_LEN_EQ_1,
I2C_EVENT_TRANSFER_DONE_LEN_EQ_2,
I2C_EVENT_TRANSFER_DONE_LEN_GT_2,
I2C_EVENT_NACK,
I2C_EVENT_STOPPED,
I2C_EVENT_AUTO, /* FIXME: remove this */
I2C_EVENT_NUM_EVENTS /* Must be last */
};
#if defined(PIOS_I2C_DIAGNOSTICS)
static struct pios_i2c_fault_history i2c_adapter_fault_history;
volatile uint32_t i2c_evirq_history[I2C_LOG_DEPTH];
volatile uint8_t i2c_evirq_history_pointer = 0;
volatile uint32_t i2c_erirq_history[I2C_LOG_DEPTH];
volatile uint8_t i2c_erirq_history_pointer = 0;
volatile enum i2c_adapter_state i2c_state_history[I2C_LOG_DEPTH];
volatile uint8_t i2c_state_history_pointer = 0;
volatile enum i2c_adapter_event i2c_state_event_history[I2C_LOG_DEPTH];
volatile uint8_t i2c_state_event_history_pointer;
static uint8_t i2c_fsm_fault_count = 0;
static uint8_t i2c_bad_event_counter = 0;
static uint8_t i2c_error_interrupt_counter = 0;
static uint8_t i2c_nack_counter = 0;
static uint8_t i2c_timeout_counter = 0;
#endif
static void go_fsm_fault(struct pios_i2c_adapter *i2c_adapter);
static void go_bus_error(struct pios_i2c_adapter *i2c_adapter);
static void go_stopping(struct pios_i2c_adapter *i2c_adapter);
static void go_stopped(struct pios_i2c_adapter *i2c_adapter);
static void go_starting(struct pios_i2c_adapter *i2c_adapter);
static void go_r_any_txn_addr(struct pios_i2c_adapter *i2c_adapter);
static void go_r_more_txn_pre_one(struct pios_i2c_adapter *i2c_adapter);
static void go_r_last_txn_pre_one(struct pios_i2c_adapter *i2c_adapter);
static void go_r_any_txn_pre_first(struct pios_i2c_adapter *i2c_adapter);
static void go_r_any_txn_pre_middle(struct pios_i2c_adapter *i2c_adapter);
static void go_r_last_txn_pre_last(struct pios_i2c_adapter *i2c_adapter);
static void go_r_more_txn_pre_last(struct pios_i2c_adapter *i2c_adapter);
static void go_r_any_txn_post_last(struct pios_i2c_adapter *i2c_adapter);
static void go_w_any_txn_addr(struct pios_i2c_adapter *i2c_adapter);
static void go_w_any_txn_middle(struct pios_i2c_adapter *i2c_adapter);
static void go_w_more_txn_last(struct pios_i2c_adapter *i2c_adapter);
static void go_w_last_txn_last(struct pios_i2c_adapter *i2c_adapter);
static void go_nack(struct pios_i2c_adapter *i2c_adapter);
struct i2c_adapter_transition {
void (*entry_fn)(struct pios_i2c_adapter *i2c_adapter);
enum i2c_adapter_state next_state[I2C_EVENT_NUM_EVENTS];
};
static void i2c_adapter_process_auto(struct pios_i2c_adapter *i2c_adapter);
static void i2c_adapter_inject_event(struct pios_i2c_adapter *i2c_adapter, enum i2c_adapter_event event);
static void i2c_adapter_fsm_init(struct pios_i2c_adapter *i2c_adapter);
static bool i2c_adapter_wait_for_stopped(struct pios_i2c_adapter *i2c_adapter);
static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter);
static void i2c_adapter_log_fault(enum pios_i2c_error_type type);
static bool i2c_adapter_callback_handler(struct pios_i2c_adapter *i2c_adapter);
static const struct i2c_adapter_transition i2c_adapter_transitions[I2C_STATE_NUM_STATES] = {
[I2C_STATE_FSM_FAULT] = {
.entry_fn = go_fsm_fault,
.next_state = {
[I2C_EVENT_AUTO] = I2C_STATE_STOPPING,
},
},
[I2C_STATE_BUS_ERROR] = {
.entry_fn = go_bus_error,
.next_state = {
[I2C_EVENT_AUTO] = I2C_STATE_STOPPING,
},
},
[I2C_STATE_STOPPED] = {
.entry_fn = go_stopped,
.next_state = {
[I2C_EVENT_START] = I2C_STATE_STARTING,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_STOPPING] = {
.entry_fn = go_stopping,
.next_state = {
[I2C_EVENT_STOPPED] = I2C_STATE_STOPPED,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_STARTING] = {
.entry_fn = go_starting,
.next_state = {
[I2C_EVENT_STARTED_MORE_TXN_READ] = I2C_STATE_R_MORE_TXN_ADDR,
[I2C_EVENT_STARTED_MORE_TXN_WRITE] = I2C_STATE_W_MORE_TXN_ADDR,
[I2C_EVENT_STARTED_LAST_TXN_READ] = I2C_STATE_R_LAST_TXN_ADDR,
[I2C_EVENT_STARTED_LAST_TXN_WRITE] = I2C_STATE_W_LAST_TXN_ADDR,
[I2C_EVENT_NACK] = I2C_STATE_NACK,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
/*
* Read with restart
*/
[I2C_STATE_R_MORE_TXN_ADDR] = {
.entry_fn = go_r_any_txn_addr,
.next_state = {
[I2C_EVENT_ADDR_SENT_LEN_EQ_1] = I2C_STATE_R_MORE_TXN_PRE_ONE,
[I2C_EVENT_ADDR_SENT_LEN_EQ_2] = I2C_STATE_R_MORE_TXN_PRE_FIRST,
[I2C_EVENT_ADDR_SENT_LEN_GT_2] = I2C_STATE_R_MORE_TXN_PRE_FIRST,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_MORE_TXN_PRE_ONE] = {
.entry_fn = go_r_more_txn_pre_one,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_1] = I2C_STATE_R_MORE_TXN_POST_LAST,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_MORE_TXN_PRE_FIRST] = {
.entry_fn = go_r_any_txn_pre_first,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_2] = I2C_STATE_R_MORE_TXN_PRE_LAST,
[I2C_EVENT_TRANSFER_DONE_LEN_GT_2] = I2C_STATE_R_MORE_TXN_PRE_MIDDLE,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_MORE_TXN_PRE_MIDDLE] = {
.entry_fn = go_r_any_txn_pre_middle,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_2] = I2C_STATE_R_MORE_TXN_PRE_LAST,
[I2C_EVENT_TRANSFER_DONE_LEN_GT_2] = I2C_STATE_R_MORE_TXN_PRE_MIDDLE,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_MORE_TXN_PRE_LAST] = {
.entry_fn = go_r_more_txn_pre_last,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_1] = I2C_STATE_R_MORE_TXN_POST_LAST,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_MORE_TXN_POST_LAST] = {
.entry_fn = go_r_any_txn_post_last,
.next_state = {
[I2C_EVENT_AUTO] = I2C_STATE_STARTING,
},
},
/*
* Read
*/
[I2C_STATE_R_LAST_TXN_ADDR] = {
.entry_fn = go_r_any_txn_addr,
.next_state = {
[I2C_EVENT_ADDR_SENT_LEN_EQ_1] = I2C_STATE_R_LAST_TXN_PRE_ONE,
[I2C_EVENT_ADDR_SENT_LEN_EQ_2] = I2C_STATE_R_LAST_TXN_PRE_FIRST,
[I2C_EVENT_ADDR_SENT_LEN_GT_2] = I2C_STATE_R_LAST_TXN_PRE_FIRST,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_LAST_TXN_PRE_ONE] = {
.entry_fn = go_r_last_txn_pre_one,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_1] = I2C_STATE_R_LAST_TXN_POST_LAST,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_LAST_TXN_PRE_FIRST] = {
.entry_fn = go_r_any_txn_pre_first,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_2] = I2C_STATE_R_LAST_TXN_PRE_LAST,
[I2C_EVENT_TRANSFER_DONE_LEN_GT_2] = I2C_STATE_R_LAST_TXN_PRE_MIDDLE,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_LAST_TXN_PRE_MIDDLE] = {
.entry_fn = go_r_any_txn_pre_middle,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_2] = I2C_STATE_R_LAST_TXN_PRE_LAST,
[I2C_EVENT_TRANSFER_DONE_LEN_GT_2] = I2C_STATE_R_LAST_TXN_PRE_MIDDLE,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_LAST_TXN_PRE_LAST] = {
.entry_fn = go_r_last_txn_pre_last,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_1] = I2C_STATE_R_LAST_TXN_POST_LAST,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_R_LAST_TXN_POST_LAST] = {
.entry_fn = go_r_any_txn_post_last,
.next_state = {
[I2C_EVENT_AUTO] = I2C_STATE_STOPPING,
},
},
/*
* Write with restart
*/
[I2C_STATE_W_MORE_TXN_ADDR] = {
.entry_fn = go_w_any_txn_addr,
.next_state = {
[I2C_EVENT_ADDR_SENT_LEN_EQ_1] = I2C_STATE_W_MORE_TXN_LAST,
[I2C_EVENT_ADDR_SENT_LEN_EQ_2] = I2C_STATE_W_MORE_TXN_MIDDLE,
[I2C_EVENT_ADDR_SENT_LEN_GT_2] = I2C_STATE_W_MORE_TXN_MIDDLE,
[I2C_EVENT_NACK] = I2C_STATE_NACK,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_W_MORE_TXN_MIDDLE] = {
.entry_fn = go_w_any_txn_middle,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_1] = I2C_STATE_W_MORE_TXN_LAST,
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_2] = I2C_STATE_W_MORE_TXN_MIDDLE,
[I2C_EVENT_TRANSFER_DONE_LEN_GT_2] = I2C_STATE_W_MORE_TXN_MIDDLE,
[I2C_EVENT_NACK] = I2C_STATE_NACK,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_W_MORE_TXN_LAST] = {
.entry_fn = go_w_more_txn_last,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_0] = I2C_STATE_STARTING,
[I2C_EVENT_NACK] = I2C_STATE_NACK,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
/*
* Write
*/
[I2C_STATE_W_LAST_TXN_ADDR] = {
.entry_fn = go_w_any_txn_addr,
.next_state = {
[I2C_EVENT_ADDR_SENT_LEN_EQ_1] = I2C_STATE_W_LAST_TXN_LAST,
[I2C_EVENT_ADDR_SENT_LEN_EQ_2] = I2C_STATE_W_LAST_TXN_MIDDLE,
[I2C_EVENT_ADDR_SENT_LEN_GT_2] = I2C_STATE_W_LAST_TXN_MIDDLE,
[I2C_EVENT_NACK] = I2C_STATE_NACK,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_W_LAST_TXN_MIDDLE] = {
.entry_fn = go_w_any_txn_middle,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_1] = I2C_STATE_W_LAST_TXN_LAST,
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_2] = I2C_STATE_W_LAST_TXN_MIDDLE,
[I2C_EVENT_TRANSFER_DONE_LEN_GT_2] = I2C_STATE_W_LAST_TXN_MIDDLE,
[I2C_EVENT_NACK] = I2C_STATE_NACK,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_W_LAST_TXN_LAST] = {
.entry_fn = go_w_last_txn_last,
.next_state = {
[I2C_EVENT_TRANSFER_DONE_LEN_EQ_0] = I2C_STATE_STOPPING,
[I2C_EVENT_NACK] = I2C_STATE_NACK,
[I2C_EVENT_BUS_ERROR] = I2C_STATE_BUS_ERROR,
},
},
[I2C_STATE_NACK] = {
.entry_fn = go_nack,
.next_state = {
[I2C_EVENT_AUTO] = I2C_STATE_STOPPING,
},
},
};
static void go_fsm_fault(struct pios_i2c_adapter *i2c_adapter)
{
#if defined(I2C_HALT_ON_ERRORS)
PIOS_DEBUG_Assert(0);
#endif
/* Note that this transfer has hit a bus error */
i2c_adapter->bus_error = true;
i2c_adapter_reset_bus(i2c_adapter);
}
static void go_bus_error(struct pios_i2c_adapter *i2c_adapter)
{
/* Note that this transfer has hit a bus error */
i2c_adapter->bus_error = true;
i2c_adapter_reset_bus(i2c_adapter);
}
static void go_stopping(struct pios_i2c_adapter *i2c_adapter)
{
#ifdef USE_FREERTOS
signed portBASE_TYPE pxHigherPriorityTaskWoken = pdFALSE;
#endif
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, DISABLE);
#ifdef USE_FREERTOS
if (xSemaphoreGiveFromISR(i2c_adapter->sem_ready, &pxHigherPriorityTaskWoken) != pdTRUE) {
#if defined(I2C_HALT_ON_ERRORS)
PIOS_DEBUG_Assert(0);
#endif
}
portEND_SWITCHING_ISR(pxHigherPriorityTaskWoken); /* FIXME: is this the right place for this? */
#endif /* USE_FREERTOS */
if (i2c_adapter->callback) {
i2c_adapter_callback_handler(i2c_adapter);
}
}
static void go_stopped(struct pios_i2c_adapter *i2c_adapter)
{
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, DISABLE);
I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, ENABLE);
}
static void go_starting(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn >= i2c_adapter->first_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
// check for an empty read/write
if (i2c_adapter->active_txn->buf != NULL && i2c_adapter->active_txn->len != 0) {
// Data available
i2c_adapter->active_byte = &(i2c_adapter->active_txn->buf[0]);
i2c_adapter->last_byte = &(i2c_adapter->active_txn->buf[i2c_adapter->active_txn->len - 1]);
} else {
// No Data available => Empty read/write
i2c_adapter->last_byte = NULL;
i2c_adapter->active_byte = i2c_adapter->last_byte + 1;
}
I2C_GenerateSTART(i2c_adapter->cfg->regs, ENABLE);
if (i2c_adapter->active_txn->rw == PIOS_I2C_TXN_READ) {
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, ENABLE);
} else {
// For write operations, do not enable the IT_BUF events.
// The current driver does not act when the TX data register is not full, only when the complete byte is sent.
// With the IT_BUF enabled, we constantly get IRQs, See OP-326
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_ERR, ENABLE);
}
}
/* Common to 'more' and 'last' transaction */
static void go_r_any_txn_addr(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn >= i2c_adapter->first_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn->rw == PIOS_I2C_TXN_READ);
I2C_Send7bitAddress(i2c_adapter->cfg->regs, (i2c_adapter->active_txn->addr) << 1, I2C_Direction_Receiver);
}
static void go_r_more_txn_pre_one(struct pios_i2c_adapter *i2c_adapter)
{
I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, DISABLE);
I2C_GenerateSTART(i2c_adapter->cfg->regs, ENABLE);
}
static void go_r_last_txn_pre_one(struct pios_i2c_adapter *i2c_adapter)
{
I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, DISABLE);
I2C_GenerateSTOP(i2c_adapter->cfg->regs, ENABLE);
}
/* Common to 'more' and 'last' transaction */
static void go_r_any_txn_pre_first(struct pios_i2c_adapter *i2c_adapter)
{
I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, ENABLE);
}
/* Common to 'more' and 'last' transaction */
static void go_r_any_txn_pre_middle(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
*(i2c_adapter->active_byte) = I2C_ReceiveData(i2c_adapter->cfg->regs);
/* Move to the next byte */
i2c_adapter->active_byte++;
PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
}
static void go_r_more_txn_pre_last(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, DISABLE);
PIOS_IRQ_Disable();
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, DISABLE);
I2C_GenerateSTART(i2c_adapter->cfg->regs, ENABLE);
*(i2c_adapter->active_byte) = I2C_ReceiveData(i2c_adapter->cfg->regs);
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, ENABLE);
PIOS_IRQ_Enable();
/* Move to the next byte */
i2c_adapter->active_byte++;
PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
}
static void go_r_last_txn_pre_last(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, DISABLE);
PIOS_IRQ_Disable();
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, DISABLE);
I2C_GenerateSTOP(i2c_adapter->cfg->regs, ENABLE);
*(i2c_adapter->active_byte) = I2C_ReceiveData(i2c_adapter->cfg->regs);
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, ENABLE);
PIOS_IRQ_Enable();
/* Move to the next byte */
i2c_adapter->active_byte++;
PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
}
/* Common to 'more' and 'last' transaction */
static void go_r_any_txn_post_last(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_byte == i2c_adapter->last_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn >= i2c_adapter->first_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
*(i2c_adapter->active_byte) = I2C_ReceiveData(i2c_adapter->cfg->regs);
/* Move to the next byte */
i2c_adapter->active_byte++;
/* Move to the next transaction */
i2c_adapter->active_txn++;
}
/* Common to 'more' and 'last' transaction */
static void go_w_any_txn_addr(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn >= i2c_adapter->first_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn->rw == PIOS_I2C_TXN_WRITE);
I2C_Send7bitAddress(i2c_adapter->cfg->regs, (i2c_adapter->active_txn->addr) << 1, I2C_Direction_Transmitter);
}
static void go_w_any_txn_middle(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_byte < i2c_adapter->last_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn >= i2c_adapter->first_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
I2C_SendData(i2c_adapter->cfg->regs, *(i2c_adapter->active_byte));
/* Move to the next byte */
i2c_adapter->active_byte++;
PIOS_DEBUG_Assert(i2c_adapter->active_byte <= i2c_adapter->last_byte);
}
static void go_w_more_txn_last(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_byte == i2c_adapter->last_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn >= i2c_adapter->first_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
I2C_SendData(i2c_adapter->cfg->regs, *(i2c_adapter->active_byte));
/* Move to the next byte */
i2c_adapter->active_byte++;
/* Move to the next transaction */
i2c_adapter->active_txn++;
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
}
static void go_w_last_txn_last(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_DEBUG_Assert(i2c_adapter->active_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_byte == i2c_adapter->last_byte);
PIOS_DEBUG_Assert(i2c_adapter->active_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn >= i2c_adapter->first_txn);
PIOS_DEBUG_Assert(i2c_adapter->active_txn <= i2c_adapter->last_txn);
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_BUF, DISABLE);
I2C_SendData(i2c_adapter->cfg->regs, *(i2c_adapter->active_byte));
// SHOULD MOVE THIS INTO A STOPPING STATE AND SET IT ONLY AFTER THE BYTE WAS SENT
I2C_GenerateSTOP(i2c_adapter->cfg->regs, ENABLE);
/* Move to the next byte */
i2c_adapter->active_byte++;
}
static void go_nack(struct pios_i2c_adapter *i2c_adapter)
{
i2c_adapter->nack = true;
I2C_ITConfig(i2c_adapter->cfg->regs, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, DISABLE);
I2C_AcknowledgeConfig(i2c_adapter->cfg->regs, DISABLE);
I2C_GenerateSTOP(i2c_adapter->cfg->regs, ENABLE);
}
static void i2c_adapter_inject_event(struct pios_i2c_adapter *i2c_adapter, enum i2c_adapter_event event)
{
PIOS_IRQ_Disable();
#if defined(PIOS_I2C_DIAGNOSTICS)
i2c_state_event_history[i2c_state_event_history_pointer] = event;
i2c_state_event_history_pointer = (i2c_state_event_history_pointer + 1) % I2C_LOG_DEPTH;
i2c_state_history[i2c_state_history_pointer] = i2c_adapter->curr_state;
i2c_state_history_pointer = (i2c_state_history_pointer + 1) % I2C_LOG_DEPTH;
if (i2c_adapter_transitions[i2c_adapter->curr_state].next_state[event] == I2C_STATE_FSM_FAULT) {
i2c_adapter_log_fault(PIOS_I2C_ERROR_FSM);
}
#endif
/*
* Move to the next state
*
* This is done prior to calling the new state's entry function to
* guarantee that the entry function never depends on the previous
* state. This way, it cannot ever know what the previous state was.
*/
i2c_adapter->curr_state = i2c_adapter_transitions[i2c_adapter->curr_state].next_state[event];
/* Call the entry function (if any) for the next state. */
if (i2c_adapter_transitions[i2c_adapter->curr_state].entry_fn) {
i2c_adapter_transitions[i2c_adapter->curr_state].entry_fn(i2c_adapter);
}
/* Process any AUTO transitions in the FSM */
i2c_adapter_process_auto(i2c_adapter);
PIOS_IRQ_Enable();
}
static void i2c_adapter_process_auto(struct pios_i2c_adapter *i2c_adapter)
{
PIOS_IRQ_Disable();
while (i2c_adapter_transitions[i2c_adapter->curr_state].next_state[I2C_EVENT_AUTO]) {
i2c_adapter->curr_state = i2c_adapter_transitions[i2c_adapter->curr_state].next_state[I2C_EVENT_AUTO];
/* Call the entry function (if any) for the next state. */
if (i2c_adapter_transitions[i2c_adapter->curr_state].entry_fn) {
i2c_adapter_transitions[i2c_adapter->curr_state].entry_fn(i2c_adapter);
}
}
PIOS_IRQ_Enable();
}
static void i2c_adapter_fsm_init(struct pios_i2c_adapter *i2c_adapter)
{
i2c_adapter_reset_bus(i2c_adapter);
i2c_adapter->curr_state = I2C_STATE_STOPPED;
}
static bool i2c_adapter_wait_for_stopped(struct pios_i2c_adapter *i2c_adapter)
{
uint32_t guard;
/*
* Wait for the bus to return to the stopped state.
* This was pulled out of the FSM due to occasional
* failures at this transition which previously resulted
* in spinning on this bit in the ISR forever.
*/
for (guard = 1000000; /* FIXME: should use the configured bus timeout */
guard && (i2c_adapter->cfg->regs->CR1 & I2C_CR1_STOP); guard--) {
continue;
}
if (!guard) {
/* We timed out waiting for the stop condition */
return false;
}
return true;
}
static void i2c_adapter_reset_bus(struct pios_i2c_adapter *i2c_adapter)
{
/* Reset the I2C block */
I2C_DeInit(i2c_adapter->cfg->regs);
/* Make sure the bus is free by clocking it until any slaves release the bus. */
GPIO_InitTypeDef scl_gpio_init;
scl_gpio_init = i2c_adapter->cfg->scl.init;
scl_gpio_init.GPIO_Mode = GPIO_Mode_OUT;
GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
GPIO_Init(i2c_adapter->cfg->scl.gpio, &scl_gpio_init);
GPIO_InitTypeDef sda_gpio_init;
sda_gpio_init = i2c_adapter->cfg->sda.init;
sda_gpio_init.GPIO_Mode = GPIO_Mode_OUT;
GPIO_SetBits(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin);
GPIO_Init(i2c_adapter->cfg->sda.gpio, &sda_gpio_init);
/* Check SDA line to determine if slave is asserting bus and clock out if so, this may */
/* have to be repeated (due to futher bus errors) but better than clocking 0xFF into an */
/* ESC */
// bool sda_hung = GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET;
while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) == Bit_RESET) {
/* Set clock high and wait for any clock stretching to finish. */
GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET) {
;
}
PIOS_DELAY_WaituS(2);
/* Set clock low */
GPIO_ResetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
PIOS_DELAY_WaituS(2);
/* Clock high again */
GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
PIOS_DELAY_WaituS(2);
}
/* Generate a start then stop condition */
GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
PIOS_DELAY_WaituS(2);
GPIO_ResetBits(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin);
PIOS_DELAY_WaituS(2);
GPIO_ResetBits(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin);
PIOS_DELAY_WaituS(2);
/* Set data and clock high and wait for any clock stretching to finish. */
GPIO_SetBits(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin);
GPIO_SetBits(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin);
while (GPIO_ReadInputDataBit(i2c_adapter->cfg->scl.gpio, i2c_adapter->cfg->scl.init.GPIO_Pin) == Bit_RESET) {
;
}
/* Wait for data to be high */
while (GPIO_ReadInputDataBit(i2c_adapter->cfg->sda.gpio, i2c_adapter->cfg->sda.init.GPIO_Pin) != Bit_SET) {
;
}
/* Bus signals are guaranteed to be high (ie. free) after this point */
/* Initialize the GPIO pins to the peripheral function */
if (i2c_adapter->cfg->remapSCL) {
GPIO_PinAFConfig(i2c_adapter->cfg->scl.gpio,
__builtin_ctz(i2c_adapter->cfg->scl.init.GPIO_Pin),
i2c_adapter->cfg->remapSCL);
}
if (i2c_adapter->cfg->remapSDA) {
GPIO_PinAFConfig(i2c_adapter->cfg->sda.gpio,
__builtin_ctz(i2c_adapter->cfg->sda.init.GPIO_Pin),
i2c_adapter->cfg->remapSDA);
}
GPIO_Init(i2c_adapter->cfg->scl.gpio, (GPIO_InitTypeDef *)&(i2c_adapter->cfg->scl.init)); // Struct is const, function signature not
GPIO_Init(i2c_adapter->cfg->sda.gpio, (GPIO_InitTypeDef *)&(i2c_adapter->cfg->sda.init));
/* Reset the I2C block */
I2C_DeInit(i2c_adapter->cfg->regs);
/* Initialize the I2C block */
I2C_Init(i2c_adapter->cfg->regs, (I2C_InitTypeDef *)&(i2c_adapter->cfg->init));
// for delays during transfer timeouts
// one tick correspond to transmission of 1 byte i.e. 9 clock ticks
i2c_adapter->transfer_delay_uS = 9000000 / (((I2C_InitTypeDef *)&(i2c_adapter->cfg->init))->I2C_ClockSpeed);
if (i2c_adapter->cfg->regs->SR2 & I2C_FLAG_BUSY) {
/* Reset the I2C block */
I2C_SoftwareResetCmd(i2c_adapter->cfg->regs, ENABLE);
I2C_SoftwareResetCmd(i2c_adapter->cfg->regs, DISABLE);
}
}
/* Return true if the FSM is in a terminal state */
static bool i2c_adapter_fsm_terminated(struct pios_i2c_adapter *i2c_adapter)
{
switch (i2c_adapter->curr_state) {
case I2C_STATE_STOPPING:
case I2C_STATE_STOPPED:
return true;
default:
return false;
}
}
uint32_t i2c_cb_count = 0;
static bool i2c_adapter_callback_handler(struct pios_i2c_adapter *i2c_adapter)
{
bool semaphore_success = true;
/* Wait for the transfer to complete */
#ifdef USE_FREERTOS
portTickType timeout;
timeout = i2c_adapter->cfg->transfer_timeout_ms / portTICK_RATE_MS;
semaphore_success &= (xSemaphoreTake(i2c_adapter->sem_ready, timeout) == pdTRUE);
xSemaphoreGive(i2c_adapter->sem_ready);
#endif /* USE_FREERTOS */
/* transfer_timeout_ticks is set by PIOS_I2C_Transfer_Callback */
/* Spin waiting for the transfer to finish */
while (!i2c_adapter_fsm_terminated(i2c_adapter)) {
// sleep 1 byte, as FSM can't be faster
// FIXME: clock stretching could make problems, but citing NPX: alsmost no slave device implements clock stretching
// three times the expected time should cover clock delay
PIOS_DELAY_WaituS(i2c_adapter->transfer_delay_uS);
i2c_adapter->transfer_timeout_ticks--;
if (i2c_adapter->transfer_timeout_ticks == 0) {
break;
}
}
if (i2c_adapter_wait_for_stopped(i2c_adapter)) {
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_STOPPED);
} else {
i2c_adapter_fsm_init(i2c_adapter);
}
// Execute user supplied function
i2c_adapter->callback();
i2c_cb_count++;
#ifdef USE_FREERTOS
/* Unlock the bus */
xSemaphoreGive(i2c_adapter->sem_busy);
if (!semaphore_success) {
i2c_timeout_counter++;
}
#else
PIOS_IRQ_Disable();
i2c_adapter->busy = 0;
PIOS_IRQ_Enable();
#endif /* USE_FREERTOS */
return (!i2c_adapter->bus_error) && semaphore_success;
}
/**
* Logs the last N state transitions and N IRQ events due to
* an error condition
* \param[in] i2c the adapter number to log an event for
*/
void i2c_adapter_log_fault(enum pios_i2c_error_type type)
{
#if defined(PIOS_I2C_DIAGNOSTICS)
i2c_adapter_fault_history.type = type;
for (uint8_t i = 0; i < I2C_LOG_DEPTH; i++) {
i2c_adapter_fault_history.evirq[i] =
i2c_evirq_history[(I2C_LOG_DEPTH + i2c_evirq_history_pointer - 1 - i) % I2C_LOG_DEPTH];
i2c_adapter_fault_history.erirq[i] =
i2c_erirq_history[(I2C_LOG_DEPTH + i2c_erirq_history_pointer - 1 - i) % I2C_LOG_DEPTH];
i2c_adapter_fault_history.event[i] =
i2c_state_event_history[(I2C_LOG_DEPTH + i2c_state_event_history_pointer - 1 - i) % I2C_LOG_DEPTH];
i2c_adapter_fault_history.state[i] =
i2c_state_history[(I2C_LOG_DEPTH + i2c_state_history_pointer - 1 - i) % I2C_LOG_DEPTH];
}
switch (type) {
case PIOS_I2C_ERROR_EVENT:
i2c_bad_event_counter++;
break;
case PIOS_I2C_ERROR_FSM:
i2c_fsm_fault_count++;
break;
case PIOS_I2C_ERROR_INTERRUPT:
i2c_error_interrupt_counter++;
break;
}
#endif /* if defined(PIOS_I2C_DIAGNOSTICS) */
}
/**
* Logs the last N state transitions and N IRQ events due to
* an error condition
* \param[out] data address where to copy the pios_i2c_fault_history structure to
* \param[out] counts three uint16 that receive the bad event, fsm, and error irq
* counts
*/
void PIOS_I2C_GetDiagnostics(struct pios_i2c_fault_history *data, uint8_t *counts)
{
#if defined(PIOS_I2C_DIAGNOSTICS)
memcpy(data, &i2c_adapter_fault_history, sizeof(i2c_adapter_fault_history));
counts[0] = i2c_bad_event_counter;
counts[1] = i2c_fsm_fault_count;
counts[2] = i2c_error_interrupt_counter;
counts[3] = i2c_nack_counter;
counts[4] = i2c_timeout_counter;
#else
struct pios_i2c_fault_history i2c_adapter_fault_history;
i2c_adapter_fault_history.type = PIOS_I2C_ERROR_EVENT;
memcpy(data, &i2c_adapter_fault_history, sizeof(i2c_adapter_fault_history));
counts[0] = counts[1] = counts[2] = 0;
#endif
}
static bool PIOS_I2C_validate(struct pios_i2c_adapter *i2c_adapter)
{
return i2c_adapter->magic == PIOS_I2C_DEV_MAGIC;
}
#if defined(PIOS_INCLUDE_FREERTOS) && 0
static struct pios_i2c_dev *PIOS_I2C_alloc(void)
{
struct pios_i2c_dev *i2c_adapter;
i2c_adapter = (struct pios_i2c_adapter *)pios_malloc(sizeof(*i2c_adapter));
if (!i2c_adapter) {
return NULL;
}
i2c_adapter->magic = PIOS_I2C_DEV_MAGIC;
return i2c_adapter;
}
#else
static struct pios_i2c_adapter pios_i2c_adapters[PIOS_I2C_MAX_DEVS];
static uint8_t pios_i2c_num_adapters;
static struct pios_i2c_adapter *PIOS_I2C_alloc(void)
{
struct pios_i2c_adapter *i2c_adapter;
if (pios_i2c_num_adapters >= PIOS_I2C_MAX_DEVS) {
return NULL;
}
i2c_adapter = &pios_i2c_adapters[pios_i2c_num_adapters++];
i2c_adapter->magic = PIOS_I2C_DEV_MAGIC;
return i2c_adapter;
}
#endif /* if defined(PIOS_INCLUDE_FREERTOS) && 0 */
/**
* Initializes IIC driver
* \param[in] mode currently only mode 0 supported
* \return < 0 if initialisation failed
*/
int32_t PIOS_I2C_Init(uint32_t *i2c_id, const struct pios_i2c_adapter_cfg *cfg)
{
PIOS_DEBUG_Assert(i2c_id);
PIOS_DEBUG_Assert(cfg);
struct pios_i2c_adapter *i2c_adapter;
i2c_adapter = (struct pios_i2c_adapter *)PIOS_I2C_alloc();
if (!i2c_adapter) {
goto out_fail;
}
/* Bind the configuration to the device instance */
i2c_adapter->cfg = cfg;
#ifdef USE_FREERTOS
/*
* Must be done prior to calling i2c_adapter_fsm_init()
* since the sem_ready mutex is used in the initial state.
*/
vSemaphoreCreateBinary(i2c_adapter->sem_ready);
i2c_adapter->sem_busy = xSemaphoreCreateMutex();
#else
i2c_adapter->busy = 0;
#endif // USE_FREERTOS
/* Initialize the state machine */
i2c_adapter_fsm_init(i2c_adapter);
*i2c_id = (uint32_t)i2c_adapter;
/* Configure and enable I2C interrupts */
NVIC_Init((NVIC_InitTypeDef *)&(i2c_adapter->cfg->event.init));
NVIC_Init((NVIC_InitTypeDef *)&(i2c_adapter->cfg->error.init));
/* No error */
return 0;
out_fail:
return -1;
}
int32_t PIOS_I2C_Transfer(uint32_t i2c_id, const struct pios_i2c_txn txn_list[], uint32_t num_txns)
{
struct pios_i2c_adapter *i2c_adapter = (struct pios_i2c_adapter *)i2c_id;
if (!PIOS_I2C_validate(i2c_adapter)) {
return -1;
}
PIOS_DEBUG_Assert(txn_list);
PIOS_DEBUG_Assert(num_txns);
bool semaphore_success = true;
#ifdef USE_FREERTOS
/* Lock the bus */
portTickType timeout;
timeout = i2c_adapter->cfg->transfer_timeout_ms / portTICK_RATE_MS;
if (xSemaphoreTake(i2c_adapter->sem_busy, timeout) == pdFALSE) {
return -2;
}
#else
PIOS_IRQ_Disable();
if (i2c_adapter->busy) {
PIOS_IRQ_Enable();
return -2;
}
i2c_adapter->busy = 1;
PIOS_IRQ_Enable();
#endif /* USE_FREERTOS */
PIOS_DEBUG_Assert(i2c_adapter->curr_state == I2C_STATE_STOPPED);
i2c_adapter->first_txn = &txn_list[0];
i2c_adapter->last_txn = &txn_list[num_txns - 1];
i2c_adapter->active_txn = i2c_adapter->first_txn;
#ifdef USE_FREERTOS
/* Make sure the done/ready semaphore is consumed before we start */
semaphore_success &= (xSemaphoreTake(i2c_adapter->sem_ready, timeout) == pdTRUE);
#endif
// Estimate bytes of transmission. Per txns: 1 adress byte + length
i2c_adapter->transfer_timeout_ticks = num_txns;
for (uint32_t i = 0; i < num_txns; i++) {
i2c_adapter->transfer_timeout_ticks += txn_list[i].len;
}
// timeout if it takes eight times the expected time
i2c_adapter->transfer_timeout_ticks <<= 3;
i2c_adapter->callback = NULL;
i2c_adapter->bus_error = false;
i2c_adapter->nack = false;
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_START);
/* Wait for the transfer to complete */
#ifdef USE_FREERTOS
semaphore_success &= (xSemaphoreTake(i2c_adapter->sem_ready, timeout) == pdTRUE);
xSemaphoreGive(i2c_adapter->sem_ready);
#endif /* USE_FREERTOS */
/* Spin waiting for the transfer to finish */
while (!i2c_adapter_fsm_terminated(i2c_adapter)) {
/* sleep 9 clock ticks (1 byte), because FSM can't be faster than one byte
FIXME: clock stretching could make problems, but citing NPX: alsmost no slave device implements clock stretching
three times the expected time should cover clock delay */
PIOS_DELAY_WaituS(i2c_adapter->transfer_delay_uS);
i2c_adapter->transfer_timeout_ticks--;
if (i2c_adapter->transfer_timeout_ticks == 0) {
break;
}
}
if (i2c_adapter_wait_for_stopped(i2c_adapter)) {
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_STOPPED);
} else {
i2c_adapter_fsm_init(i2c_adapter);
}
#ifdef USE_FREERTOS
/* Unlock the bus */
xSemaphoreGive(i2c_adapter->sem_busy);
if (!semaphore_success) {
i2c_timeout_counter++;
}
#else
PIOS_IRQ_Disable();
i2c_adapter->busy = 0;
PIOS_IRQ_Enable();
#endif /* USE_FREERTOS */
return !semaphore_success ? -2 :
i2c_adapter->bus_error ? -1 :
i2c_adapter->nack ? -3 :
0;
}
int32_t PIOS_I2C_Transfer_Callback(uint32_t i2c_id, const struct pios_i2c_txn txn_list[], uint32_t num_txns, void *callback)
{
struct pios_i2c_adapter *i2c_adapter = (struct pios_i2c_adapter *)i2c_id;
if (!PIOS_I2C_validate(i2c_adapter)) {
return -1;
}
PIOS_Assert(callback);
PIOS_DEBUG_Assert(txn_list);
PIOS_DEBUG_Assert(num_txns);
bool semaphore_success = true;
#ifdef USE_FREERTOS
/* Lock the bus */
portTickType timeout;
timeout = i2c_adapter->cfg->transfer_timeout_ms / portTICK_RATE_MS;
if (xSemaphoreTake(i2c_adapter->sem_busy, timeout) == pdFALSE) {
return -2;
}
#else
if (i2c_adapter->busy) {
PIOS_IRQ_Enable();
return -2;
}
#endif /* USE_FREERTOS */
PIOS_DEBUG_Assert(i2c_adapter->curr_state == I2C_STATE_STOPPED);
i2c_adapter->first_txn = &txn_list[0];
i2c_adapter->last_txn = &txn_list[num_txns - 1];
i2c_adapter->active_txn = i2c_adapter->first_txn;
#ifdef USE_FREERTOS
/* Make sure the done/ready semaphore is consumed before we start */
semaphore_success &= (xSemaphoreTake(i2c_adapter->sem_ready, timeout) == pdTRUE);
#endif
// used in the i2c_adapter_callback_handler function
// Estimate bytes of transmission. Per txns: 1 adress byte + length
i2c_adapter->transfer_timeout_ticks = num_txns;
for (uint32_t i = 0; i < num_txns; i++) {
i2c_adapter->transfer_timeout_ticks += txn_list[i].len;
}
// timeout if it takes eight times the expected time
i2c_adapter->transfer_timeout_ticks <<= 3;
i2c_adapter->callback = callback;
i2c_adapter->bus_error = false;
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_START);
return !semaphore_success ? -2 : 0;
}
void PIOS_I2C_EV_IRQ_Handler(uint32_t i2c_id)
{
struct pios_i2c_adapter *i2c_adapter = (struct pios_i2c_adapter *)i2c_id;
if (!PIOS_I2C_validate(i2c_adapter)) {
return;
}
uint32_t event = I2C_GetLastEvent(i2c_adapter->cfg->regs);
#if defined(PIOS_I2C_DIAGNOSTICS)
/* Store event for diagnostics */
i2c_evirq_history[i2c_evirq_history_pointer] = event;
i2c_evirq_history_pointer = (i2c_evirq_history_pointer + 1) % I2C_LOG_DEPTH;
#endif
#define EVENT_MASK 0x000700FF
event &= EVENT_MASK;
// This is very poor and inconsistent practice with the FSM since no other
// throw event depends on the current state. However when accelerated (-Os)
// we definitely catch this event twice and there is no clean way to do deal
// with that in the FMS short of a special state for it
if (i2c_adapter->curr_state == I2C_STATE_STARTING && event == 0x70084) {
return;
}
switch (event) { /* Mask out all the bits we don't care about */
case (I2C_EVENT_MASTER_MODE_SELECT | 0x40):
/* Unexplained event: EV5 + RxNE : Extraneous Rx. Probably a late NACK from previous read. */
/* Clean up the extra Rx until the root cause is identified and just keep going */
(void)I2C_ReceiveData(i2c_adapter->cfg->regs);
/* Fall through */
case I2C_EVENT_MASTER_MODE_SELECT: /* EV5 */
switch (i2c_adapter->active_txn->rw) {
case PIOS_I2C_TXN_READ:
if (i2c_adapter->active_txn == i2c_adapter->last_txn) {
/* Final transaction */
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_STARTED_LAST_TXN_READ);
} else if (i2c_adapter->active_txn < i2c_adapter->last_txn) {
/* More transactions follow */
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_STARTED_MORE_TXN_READ);
} else {
PIOS_DEBUG_Assert(0);
}
break;
case PIOS_I2C_TXN_WRITE:
if (i2c_adapter->active_txn == i2c_adapter->last_txn) {
/* Final transaction */
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_STARTED_LAST_TXN_WRITE);
} else if (i2c_adapter->active_txn < i2c_adapter->last_txn) {
/* More transactions follow */
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_STARTED_MORE_TXN_WRITE);
} else {
PIOS_DEBUG_Assert(0);
}
break;
default:
PIOS_DEBUG_Assert(0);
break;
}
break;
case I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED: /* EV6 */
case I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED: /* EV6 */
switch (i2c_adapter->last_byte - i2c_adapter->active_byte + 1) {
case 0:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_ADDR_SENT_LEN_EQ_0);
break;
case 1:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_ADDR_SENT_LEN_EQ_1);
break;
case 2:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_ADDR_SENT_LEN_EQ_2);
break;
default:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_ADDR_SENT_LEN_GT_2);
break;
}
break;
case 0x80: /* TxE only. TRA + MSL + BUSY have been cleared before we got here. */
/* Ignore */
{
static volatile bool halt = false;
while (halt) {
;
}
}
break;
case 0: /* This triggers an FSM fault sometimes, but not having it stops things working */
case 0x40: /* RxNE only. MSL + BUSY have already been cleared by HW. */
case 0x44: /* RxNE + BTF. MSL + BUSY have already been cleared by HW. */
case I2C_EVENT_MASTER_BYTE_RECEIVED: /* EV7 */
case (I2C_EVENT_MASTER_BYTE_RECEIVED | 0x4): /* EV7 + BTF */
case I2C_EVENT_MASTER_BYTE_TRANSMITTED: /* EV8_2 */
case 0x84: /* TxE + BTF. EV8_2 but TRA + MSL + BUSY have already been cleared by HW. */
switch (i2c_adapter->last_byte - i2c_adapter->active_byte + 1) {
case 0:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_TRANSFER_DONE_LEN_EQ_0);
break;
case 1:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_TRANSFER_DONE_LEN_EQ_1);
break;
case 2:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_TRANSFER_DONE_LEN_EQ_2);
break;
default:
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_TRANSFER_DONE_LEN_GT_2);
break;
}
break;
case I2C_EVENT_MASTER_BYTE_TRANSMITTING: /* EV8 */
/* Ignore this event and wait for TRANSMITTED in case we can't keep up */
goto skip_event;
break;
case 0x30084: /* BUSY + MSL + TXE + BFT Occurs between byte transmitted and master mode selected */
case 0x30000: /* BUSY + MSL Need to throw away this spurious event */
case 0x30403 & EVENT_MASK: /* BUSY + MSL + SB + ADDR Detected this after got a NACK, probably stop bit */
goto skip_event;
break;
default:
i2c_adapter_log_fault(PIOS_I2C_ERROR_EVENT);
#if defined(I2C_HALT_ON_ERRORS)
PIOS_DEBUG_Assert(0);
#endif
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_BUS_ERROR);
break;
}
skip_event:
;
}
void PIOS_I2C_ER_IRQ_Handler(uint32_t i2c_id)
{
struct pios_i2c_adapter *i2c_adapter = (struct pios_i2c_adapter *)i2c_id;
if (!PIOS_I2C_validate(i2c_adapter)) {
return;
}
uint32_t event = I2C_GetLastEvent(i2c_adapter->cfg->regs);
#if defined(PIOS_I2C_DIAGNOSTICS)
i2c_erirq_history[i2c_erirq_history_pointer] = event;
i2c_erirq_history_pointer = (i2c_erirq_history_pointer + 1) % 5;
#endif
if (event & I2C_FLAG_AF) {
i2c_nack_counter++;
I2C_ClearFlag(i2c_adapter->cfg->regs, I2C_FLAG_AF);
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_NACK);
} else { /* Mostly bus errors here */
i2c_adapter_log_fault(PIOS_I2C_ERROR_INTERRUPT);
/* Fail hard on any errors for now */
i2c_adapter_inject_event(i2c_adapter, I2C_EVENT_BUS_ERROR);
}
}
#endif /* PIOS_INCLUDE_I2C */
/**
* @}
* @}
*/
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