mirror of https://github.com/ARMmbed/mbed-os.git
i2c_api implementation has been changed in order to support single byte reads and writes (the latter are used in I2CEeprom module used in CI tests, and this caused that tests-i2c-api were failing). These operations (single byte transfers) are not possible to achieve with the driver from nrf5 SDK (nrf_drv_twi), so the new implementation uses TWI HAL only.
Andrzej Puzdrowski
parent
e798edc604
commit
b1b802f96c
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@ -1,5 +1,5 @@
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/*
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* Copyright (c) 2013 Nordic Semiconductor ASA
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* Copyright (c) 2017 Nordic Semiconductor ASA
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without modification,
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@ -43,8 +43,17 @@
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#include "mbed_assert.h"
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#include "mbed_error.h"
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#include "nrf_drv_twi.h"
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#include "nrf_twi.h"
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#include "nrf_drv_common.h"
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#include "sdk_config.h"
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#include "app_util_platform.h"
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#include "nrf_gpio.h"
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#include "nrf_delay.h"
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// An arbitrary value used as the counter in loops waiting for given event
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// (e.g. STOPPED), needed to avoid infinite loops (and not involve any timers
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// or tickers).
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#define TIMEOUT_VALUE 1000
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#if DEVICE_I2C_ASYNCH
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#define TWI_IDX(obj) ((obj)->i2c.twi_idx)
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@ -53,60 +62,40 @@
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#endif
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#define TWI_INFO(obj) (&m_twi_info[TWI_IDX(obj)])
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typedef struct {
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bool initialized;
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nrf_drv_twi_config_t config;
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volatile bool transfer_finished;
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#define TWI0_INSTANCE_INDEX 0
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#define TWI1_INSTANCE_INDEX TWI0_INSTANCE_INDEX+TWI0_ENABLED
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#if DEVICE_I2C_ASYNCH
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volatile uint32_t events;
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void (*handler)(void);
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uint32_t event_mask;
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#endif
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typedef struct {
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bool initialized;
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uint32_t pselsda;
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uint32_t pselscl;
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nrf_twi_frequency_t frequency;
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bool start_twi;
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#if DEVICE_I2C_ASYNCH
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volatile bool active;
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uint8_t const *tx;
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size_t tx_length;
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uint8_t *rx;
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size_t rx_length;
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bool stop;
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volatile uint32_t events;
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void (*handler)(void);
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uint32_t evt_mask;
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#endif // DEVICE_I2C_ASYNCH
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} twi_info_t;
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static twi_info_t m_twi_info[TWI_COUNT];
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static nrf_drv_twi_t const m_twi_instances[TWI_COUNT] = {
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static NRF_TWI_Type * const m_twi_instances[TWI_COUNT] = {
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#if TWI0_ENABLED
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NRF_DRV_TWI_INSTANCE(0),
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NRF_TWI0,
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#endif
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#if TWI1_ENABLED
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NRF_DRV_TWI_INSTANCE(1),
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NRF_TWI1,
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#endif
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};
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static void twi_event_handler(nrf_drv_twi_evt_t const *event, void *context)
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{
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twi_info_t * twi_info = TWI_INFO((i2c_t *)context);
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twi_info->transfer_finished = true;
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#if DEVICE_I2C_ASYNCH
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switch (event->type) {
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case NRF_DRV_TWI_EVT_DONE:
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twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
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break;
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case NRF_DRV_TWI_EVT_ADDRESS_NACK:
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twi_info->events |= I2C_EVENT_ERROR_NO_SLAVE;
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break;
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case NRF_DRV_TWI_EVT_DATA_NACK:
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twi_info->events |= I2C_EVENT_ERROR;
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break;
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}
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if (twi_info->handler) {
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twi_info->handler();
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}
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#endif // DEVICE_I2C_ASYNCH
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}
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static uint8_t twi_address(int i2c_address)
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{
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// The TWI driver requires 7-bit slave address (without R/W bit).
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return (i2c_address >> 1);
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}
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void SPI0_TWI0_IRQHandler(void);
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void SPI1_TWI1_IRQHandler(void);
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@ -123,207 +112,580 @@ static const peripheral_handler_desc_t twi_handlers[TWI_COUNT] =
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SPI1_TWI1_IRQn,
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(uint32_t) SPI1_TWI1_IRQHandler
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}
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#endif
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#endif
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};
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#ifdef NRF51
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#define TWI_IRQ_PRIORITY APP_IRQ_PRIORITY_LOW
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#elif defined(NRF52) || defined(NRF52840_XXAA)
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#define TWI_IRQ_PRIORITY APP_IRQ_PRIORITY_LOWEST
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#endif
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#if DEVICE_I2C_ASYNCH
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static void start_asynch_rx(twi_info_t *twi_info, NRF_TWI_Type *twi)
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{
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if (twi_info->rx_length == 1 && twi_info->stop) {
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nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_STOP_MASK);
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} else {
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nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_SUSPEND_MASK);
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}
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTRX);
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}
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static void twi_irq_handler(uint8_t instance_idx)
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{
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twi_info_t *twi_info = &m_twi_info[instance_idx];
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NRF_TWI_Type *twi = m_twi_instances[instance_idx];
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if (nrf_twi_event_check(twi, NRF_TWI_EVENT_ERROR)) {
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nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
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// In case of an error, force STOP.
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// The current transfer may be suspended (if it is RX), so it must be
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// resumed before the STOP task is triggered.
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
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uint32_t errorsrc = nrf_twi_errorsrc_get_and_clear(twi);
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twi_info->events |= I2C_EVENT_ERROR;
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if (errorsrc & NRF_TWI_ERROR_ADDRESS_NACK) {
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twi_info->events |= I2C_EVENT_ERROR_NO_SLAVE;
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}
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if (errorsrc & NRF_TWI_ERROR_DATA_NACK) {
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twi_info->events |= I2C_EVENT_TRANSFER_EARLY_NACK;
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}
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}
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bool finished = false;
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if (nrf_twi_event_check(twi, NRF_TWI_EVENT_TXDSENT)) {
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nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
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MBED_ASSERT(twi_info->tx_length > 0);
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--(twi_info->tx_length);
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// Send next byte if there is still something to be sent.
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if (twi_info->tx_length > 0) {
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nrf_twi_txd_set(twi, *(twi_info->tx));
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++(twi_info->tx);
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// It TX is done, start RX if requested.
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} else if (twi_info->rx_length > 0) {
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start_asynch_rx(twi_info, twi);
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// If there is nothing more to do, finalize the transfer.
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} else {
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if (twi_info->stop) {
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
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} else {
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_SUSPEND);
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finished = true;
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}
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twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
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}
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}
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if (nrf_twi_event_check(twi, NRF_TWI_EVENT_RXDREADY)) {
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nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
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MBED_ASSERT(twi_info->rx_length > 0);
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*(twi_info->rx) = nrf_twi_rxd_get(twi);
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++(twi_info->rx);
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--(twi_info->rx_length);
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if (twi_info->rx_length > 0) {
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// If more bytes should be received, resume the transfer
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// (in case the stop condition should be generated after the next
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// byte, change the shortcuts configuration first).
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if (twi_info->rx_length == 1 && twi_info->stop) {
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nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_STOP_MASK);
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}
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
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} else {
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// If all requested bytes were received, finalize the transfer.
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finished = true;
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twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
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}
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}
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if (finished ||
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nrf_twi_event_check(twi, NRF_TWI_EVENT_STOPPED) ||
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(nrf_twi_int_enable_check(twi, NRF_TWI_INT_SUSPENDED_MASK) &&
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nrf_twi_event_check(twi, NRF_TWI_EVENT_SUSPENDED))) {
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// There is no need to clear the STOPPED and SUSPENDED events here,
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// they will no longer generate the interrupt - see below.
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nrf_twi_shorts_set(twi, 0);
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// Disable all interrupt sources.
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nrf_twi_int_disable(twi, UINT32_MAX);
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twi_info->active = false;
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if (twi_info->handler) {
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twi_info->handler();
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}
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}
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}
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#if TWI0_ENABLED
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static void irq_handler_twi0(void)
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{
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twi_irq_handler(TWI0_INSTANCE_INDEX);
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}
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#endif
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#if TWI1_ENABLED
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static void irq_handler_twi1(void)
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{
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twi_irq_handler(TWI1_INSTANCE_INDEX);
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}
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#endif
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static nrf_drv_irq_handler_t const m_twi_irq_handlers[TWI_COUNT] =
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{
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#if TWI0_ENABLED
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irq_handler_twi0,
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#endif
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#if TWI1_ENABLED
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irq_handler_twi1,
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#endif
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};
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#endif // DEVICE_I2C_ASYNCH
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static void configure_twi_pin(uint32_t pin, nrf_gpio_pin_dir_t dir)
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{
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nrf_gpio_cfg(pin,
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dir,
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NRF_GPIO_PIN_INPUT_CONNECT,
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NRF_GPIO_PIN_PULLUP,
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NRF_GPIO_PIN_S0D1,
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NRF_GPIO_PIN_NOSENSE);
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}
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static void twi_clear_bus(twi_info_t *twi_info)
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{
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// Try to set SDA high, and check if no slave tries to drive it low.
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nrf_gpio_pin_set(twi_info->pselsda);
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configure_twi_pin(twi_info->pselsda, NRF_GPIO_PIN_DIR_OUTPUT);
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// In case SDA is low, make up to 9 cycles on SCL line to help the slave
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// that pulls SDA low release it.
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if (!nrf_gpio_pin_read(twi_info->pselsda)) {
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nrf_gpio_pin_set(twi_info->pselscl);
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configure_twi_pin(twi_info->pselscl, NRF_GPIO_PIN_DIR_OUTPUT);
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nrf_delay_us(4);
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for (int i = 0; i < 9; i++) {
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if (nrf_gpio_pin_read(twi_info->pselsda)) {
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break;
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}
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nrf_gpio_pin_clear(twi_info->pselscl);
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nrf_delay_us(4);
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nrf_gpio_pin_set(twi_info->pselscl);
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nrf_delay_us(4);
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}
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// Finally, generate STOP condition to put the bus into initial state.
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nrf_gpio_pin_clear(twi_info->pselsda);
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nrf_delay_us(4);
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nrf_gpio_pin_set(twi_info->pselsda);
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}
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}
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void i2c_init(i2c_t *obj, PinName sda, PinName scl)
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{
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int i;
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for (i = 0; i < TWI_COUNT; ++i) {
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if (m_twi_info[i].initialized &&
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m_twi_info[i].config.sda == (uint32_t)sda &&
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m_twi_info[i].config.scl == (uint32_t)scl) {
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m_twi_info[i].pselsda == (uint32_t)sda &&
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m_twi_info[i].pselscl == (uint32_t)scl) {
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TWI_IDX(obj) = i;
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TWI_INFO(obj)->config.frequency = NRF_TWI_FREQ_100K;
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TWI_INFO(obj)->frequency = NRF_TWI_FREQ_100K;
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i2c_reset(obj);
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return;
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}
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}
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nrf_drv_twi_config_t const config = {
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.scl = scl,
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.sda = sda,
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.frequency = NRF_TWI_FREQ_100K,
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#ifdef NRF51
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.interrupt_priority = APP_IRQ_PRIORITY_LOW
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#elif defined(NRF52) || defined(NRF52840_XXAA)
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.interrupt_priority = APP_IRQ_PRIORITY_LOWEST
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#endif
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};
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for (i = 0; i < TWI_COUNT; ++i) {
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if (!m_twi_info[i].initialized) {
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TWI_IDX(obj) = i;
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twi_info_t *twi_info = TWI_INFO(obj);
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twi_info->initialized = true;
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twi_info->pselsda = (uint32_t)sda;
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twi_info->pselscl = (uint32_t)scl;
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twi_info->frequency = NRF_TWI_FREQ_100K;
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twi_info->start_twi = false;
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#if DEVICE_I2C_ASYNCH
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twi_info->active = false;
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#endif
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twi_clear_bus(twi_info);
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configure_twi_pin(twi_info->pselsda, NRF_GPIO_PIN_DIR_INPUT);
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configure_twi_pin(twi_info->pselscl, NRF_GPIO_PIN_DIR_INPUT);
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i2c_reset(obj);
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#if DEVICE_I2C_ASYNCH
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nrf_drv_common_per_res_acquire(m_twi_instances[i],
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m_twi_irq_handlers[i]);
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NVIC_SetVector(twi_handlers[i].IRQn, twi_handlers[i].vector);
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nrf_drv_common_irq_enable(twi_handlers[i].IRQn, TWI_IRQ_PRIORITY);
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#endif
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nrf_drv_twi_t const *twi = &m_twi_instances[i];
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ret_code_t ret_code =
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nrf_drv_twi_init(twi, &config, twi_event_handler, obj);
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if (ret_code == NRF_SUCCESS) {
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TWI_IDX(obj) = i;
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TWI_INFO(obj)->initialized = true;
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TWI_INFO(obj)->config = config;
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nrf_drv_twi_enable(twi);
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return;
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}
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return;
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}
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}
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// No available peripheral
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error("No available I2C peripheral\r\n");
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}
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void i2c_reset(i2c_t *obj)
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{
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twi_info_t *twi_info = TWI_INFO(obj);
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nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
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NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
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nrf_drv_twi_uninit(twi);
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nrf_drv_twi_init(twi, &twi_info->config, twi_event_handler, obj);
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nrf_drv_twi_enable(twi);
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nrf_twi_disable(twi);
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nrf_twi_pins_set(twi, twi_info->pselscl, twi_info->pselsda);
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nrf_twi_frequency_set(twi, twi_info->frequency);
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nrf_twi_enable(twi);
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}
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int i2c_start(i2c_t *obj)
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{
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(void)obj;
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twi_info_t *twi_info = TWI_INFO(obj);
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#if DEVICE_I2C_ASYNCH
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if (twi_info->active) {
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return I2C_ERROR_BUS_BUSY;
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}
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#endif
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twi_info->start_twi = true;
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return -1; // Not implemented.
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return 0;
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}
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int i2c_stop(i2c_t *obj)
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{
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(void)obj;
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NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
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return -1; // Not implemented.
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// The current transfer may be suspended (if it is RX), so it must be
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// resumed before the STOP task is triggered.
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
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nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
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uint32_t remaining_time = TIMEOUT_VALUE;
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do {
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if (nrf_twi_event_check(twi, NRF_TWI_EVENT_STOPPED)) {
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return 0;
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}
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} while (--remaining_time);
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return 1;
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}
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void i2c_frequency(i2c_t *obj, int hz)
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{
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twi_info_t *twi_info = TWI_INFO(obj);
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nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
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NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
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|
||||
if (hz < 250000) {
|
||||
twi_info->config.frequency = NRF_TWI_FREQ_100K;
|
||||
twi_info->frequency = NRF_TWI_FREQ_100K;
|
||||
} else if (hz < 400000) {
|
||||
twi_info->config.frequency = NRF_TWI_FREQ_250K;
|
||||
twi_info->frequency = NRF_TWI_FREQ_250K;
|
||||
} else {
|
||||
twi_info->config.frequency = NRF_TWI_FREQ_400K;
|
||||
twi_info->frequency = NRF_TWI_FREQ_400K;
|
||||
}
|
||||
nrf_twi_frequency_set(twi->reg.p_twi, twi_info->config.frequency);
|
||||
nrf_twi_frequency_set(twi, twi_info->frequency);
|
||||
}
|
||||
|
||||
static uint8_t twi_address(int i2c_address)
|
||||
{
|
||||
// The TWI peripheral requires 7-bit slave address (without R/W bit).
|
||||
return (i2c_address >> 1);
|
||||
}
|
||||
|
||||
static void start_twi_read(NRF_TWI_Type *twi, int address)
|
||||
{
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
|
||||
(void)nrf_twi_errorsrc_get_and_clear(twi);
|
||||
|
||||
nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_SUSPEND_MASK);
|
||||
|
||||
nrf_twi_address_set(twi, twi_address(address));
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTRX);
|
||||
}
|
||||
|
||||
int i2c_read(i2c_t *obj, int address, char *data, int length, int stop)
|
||||
{
|
||||
(void)stop;
|
||||
// Zero-length RX transfers are not supported. Such transfers cannot
|
||||
// be easily achieved with TWI peripheral (some dirty tricks would be
|
||||
// required for this), and they are actually useless (TX can be used
|
||||
// to check if the address is acknowledged by a slave).
|
||||
MBED_ASSERT(length > 0);
|
||||
|
||||
twi_info_t *twi_info = TWI_INFO(obj);
|
||||
nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
|
||||
|
||||
twi_info->transfer_finished = false;
|
||||
ret_code_t ret_code = nrf_drv_twi_rx(twi, twi_address(address),
|
||||
(uint8_t *)data, length);
|
||||
if (ret_code != NRF_SUCCESS) {
|
||||
return 0;
|
||||
#if DEVICE_I2C_ASYNCH
|
||||
if (twi_info->active) {
|
||||
return I2C_ERROR_BUS_BUSY;
|
||||
}
|
||||
while (!twi_info->transfer_finished) {}
|
||||
return nrf_drv_twi_data_count_get(twi);
|
||||
#endif
|
||||
twi_info->start_twi = false;
|
||||
|
||||
NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
|
||||
start_twi_read(twi, address);
|
||||
|
||||
int result = length;
|
||||
while (length > 0) {
|
||||
int byte_read_result = i2c_byte_read(obj, (stop && length == 1));
|
||||
if (byte_read_result < 0) {
|
||||
// When an error occurs, return the number of bytes that have been
|
||||
// received successfully.
|
||||
result -= length;
|
||||
// Force STOP condition.
|
||||
stop = 1;
|
||||
break;
|
||||
}
|
||||
*data++ = (uint8_t)byte_read_result;
|
||||
--length;
|
||||
}
|
||||
|
||||
if (stop) {
|
||||
(void)i2c_stop(obj);
|
||||
}
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
static uint8_t twi_byte_write(NRF_TWI_Type *twi, uint8_t data)
|
||||
{
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
|
||||
|
||||
nrf_twi_txd_set(twi, data);
|
||||
uint32_t remaining_time = TIMEOUT_VALUE;
|
||||
do {
|
||||
if (nrf_twi_event_check(twi, NRF_TWI_EVENT_TXDSENT)) {
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
|
||||
return 1; // ACK received
|
||||
}
|
||||
if (nrf_twi_event_check(twi, NRF_TWI_EVENT_ERROR)) {
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
|
||||
return 0; // some error occurred
|
||||
}
|
||||
} while (--remaining_time);
|
||||
|
||||
return 2; // timeout;
|
||||
}
|
||||
|
||||
static void start_twi_write(NRF_TWI_Type *twi, int address)
|
||||
{
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
|
||||
(void)nrf_twi_errorsrc_get_and_clear(twi);
|
||||
|
||||
nrf_twi_shorts_set(twi, 0);
|
||||
|
||||
nrf_twi_address_set(twi, twi_address(address));
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
|
||||
}
|
||||
|
||||
int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop)
|
||||
{
|
||||
twi_info_t *twi_info = TWI_INFO(obj);
|
||||
nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
|
||||
|
||||
twi_info->transfer_finished = false;
|
||||
ret_code_t ret_code = nrf_drv_twi_tx(twi, twi_address(address),
|
||||
(uint8_t const *)data, length, (stop == 0));
|
||||
if (ret_code != NRF_SUCCESS) {
|
||||
return 0;
|
||||
#if DEVICE_I2C_ASYNCH
|
||||
if (twi_info->active) {
|
||||
return I2C_ERROR_BUS_BUSY;
|
||||
}
|
||||
while (!twi_info->transfer_finished) {}
|
||||
return nrf_drv_twi_data_count_get(twi);
|
||||
#endif
|
||||
twi_info->start_twi = false;
|
||||
|
||||
NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
|
||||
start_twi_write(twi, address);
|
||||
|
||||
// Special case - transaction with no data.
|
||||
// It can be used to check if a slave acknowledges the address.
|
||||
if (length == 0) {
|
||||
nrf_twi_event_t event;
|
||||
if (stop) {
|
||||
event = NRF_TWI_EVENT_STOPPED;
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
|
||||
} else {
|
||||
event = NRF_TWI_EVENT_SUSPENDED;
|
||||
nrf_twi_event_clear(twi, event);
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_SUSPEND);
|
||||
}
|
||||
uint32_t remaining_time = TIMEOUT_VALUE;
|
||||
do {
|
||||
if (nrf_twi_event_check(twi, event)) {
|
||||
break;
|
||||
}
|
||||
} while (--remaining_time);
|
||||
|
||||
uint32_t errorsrc = nrf_twi_errorsrc_get_and_clear(twi);
|
||||
if (errorsrc & NRF_TWI_ERROR_ADDRESS_NACK) {
|
||||
if (!stop) {
|
||||
i2c_stop(obj);
|
||||
}
|
||||
return I2C_ERROR_NO_SLAVE;
|
||||
}
|
||||
|
||||
return (remaining_time ? 0 : I2C_ERROR_BUS_BUSY);
|
||||
}
|
||||
|
||||
int result = length;
|
||||
do {
|
||||
uint8_t byte_write_result = twi_byte_write(twi, (uint8_t)*data++);
|
||||
if (byte_write_result != 1) {
|
||||
if (byte_write_result == 0) {
|
||||
// Check what kind of error has been signaled by TWI.
|
||||
uint32_t errorsrc = nrf_twi_errorsrc_get_and_clear(twi);
|
||||
if (errorsrc & NRF_TWI_ERROR_ADDRESS_NACK) {
|
||||
result = I2C_ERROR_NO_SLAVE;
|
||||
} else {
|
||||
// Some other error - return the number of bytes that
|
||||
// have been sent successfully.
|
||||
result -= length;
|
||||
}
|
||||
} else {
|
||||
result = I2C_ERROR_BUS_BUSY;
|
||||
}
|
||||
// Force STOP condition.
|
||||
stop = 1;
|
||||
break;
|
||||
}
|
||||
--length;
|
||||
} while (length > 0);
|
||||
|
||||
if (stop) {
|
||||
(void)i2c_stop(obj);
|
||||
}
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
int i2c_byte_read(i2c_t *obj, int last)
|
||||
{
|
||||
(void)obj;
|
||||
(void)last;
|
||||
NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
|
||||
|
||||
return -1; // Not implemented.
|
||||
if (last) {
|
||||
nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_STOP_MASK);
|
||||
}
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
|
||||
|
||||
uint32_t remaining_time = TIMEOUT_VALUE;
|
||||
do {
|
||||
if (nrf_twi_event_check(twi, NRF_TWI_EVENT_RXDREADY)) {
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
|
||||
return nrf_twi_rxd_get(twi);
|
||||
}
|
||||
if (nrf_twi_event_check(twi, NRF_TWI_EVENT_ERROR)) {
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
|
||||
return I2C_ERROR_NO_SLAVE;
|
||||
}
|
||||
} while (--remaining_time);
|
||||
|
||||
return I2C_ERROR_BUS_BUSY;
|
||||
}
|
||||
|
||||
int i2c_byte_write(i2c_t *obj, int data)
|
||||
{
|
||||
(void)obj;
|
||||
(void)data;
|
||||
NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
|
||||
twi_info_t *twi_info = TWI_INFO(obj);
|
||||
if (twi_info->start_twi) {
|
||||
twi_info->start_twi = false;
|
||||
|
||||
return -1; // Not implemented.
|
||||
if (data & 1) {
|
||||
start_twi_read(twi, data);
|
||||
} else {
|
||||
start_twi_write(twi, data);
|
||||
}
|
||||
return 1;
|
||||
} else {
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
|
||||
// 0 - TWI signaled error (NAK is the only possibility here)
|
||||
// 1 - ACK received
|
||||
// 2 - timeout (clock stretched for too long?)
|
||||
return twi_byte_write(twi, (uint8_t)data);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
#if DEVICE_I2C_ASYNCH
|
||||
|
||||
void i2c_transfer_asynch(i2c_t *obj, const void *tx, size_t tx_length,
|
||||
void *rx, size_t rx_length, uint32_t address,
|
||||
uint32_t stop, uint32_t handler,
|
||||
uint32_t event, DMAUsage hint)
|
||||
{
|
||||
(void)stop;
|
||||
(void)hint;
|
||||
|
||||
if (i2c_active(obj)) {
|
||||
return;
|
||||
}
|
||||
if ((tx_length == 0) && (rx_length == 0)) {
|
||||
return;
|
||||
}
|
||||
|
||||
twi_info_t *twi_info = TWI_INFO(obj);
|
||||
twi_info->events = 0;
|
||||
twi_info->handler = (void (*)(void))handler;
|
||||
twi_info->event_mask = event;
|
||||
if (twi_info->active) {
|
||||
return;
|
||||
}
|
||||
twi_info->active = true;
|
||||
twi_info->events = 0;
|
||||
twi_info->handler = (void (*)(void))handler;
|
||||
twi_info->evt_mask = event;
|
||||
twi_info->tx_length = tx_length;
|
||||
twi_info->tx = tx;
|
||||
twi_info->rx_length = rx_length;
|
||||
twi_info->rx = rx;
|
||||
twi_info->stop = stop;
|
||||
|
||||
uint8_t twi_addr = twi_address(address);
|
||||
nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
|
||||
NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
|
||||
|
||||
if ((tx_length > 0) && (rx_length == 0)) {
|
||||
nrf_drv_twi_xfer_desc_t const xfer =
|
||||
NRF_DRV_TWI_XFER_DESC_TX(twi_addr, (uint8_t *)tx, tx_length);
|
||||
nrf_drv_twi_xfer(twi, &xfer,
|
||||
stop ? 0 : NRF_DRV_TWI_FLAG_TX_NO_STOP);
|
||||
}
|
||||
else if ((tx_length == 0) && (rx_length > 0)) {
|
||||
nrf_drv_twi_xfer_desc_t const xfer =
|
||||
NRF_DRV_TWI_XFER_DESC_RX(twi_addr, rx, rx_length);
|
||||
nrf_drv_twi_xfer(twi, &xfer, 0);
|
||||
}
|
||||
else if ((tx_length > 0) && (rx_length > 0)) {
|
||||
nrf_drv_twi_xfer_desc_t const xfer =
|
||||
NRF_DRV_TWI_XFER_DESC_TXRX(twi_addr,
|
||||
(uint8_t *)tx, tx_length, rx, rx_length);
|
||||
nrf_drv_twi_xfer(twi, &xfer, 0);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_SUSPENDED);
|
||||
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
|
||||
(void)nrf_twi_errorsrc_get_and_clear(twi);
|
||||
|
||||
nrf_twi_address_set(twi, twi_address(address));
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
|
||||
// TX only, or TX + RX (after a repeated start).
|
||||
if (tx_length > 0) {
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
|
||||
nrf_twi_txd_set(twi, *(twi_info->tx));
|
||||
++(twi_info->tx);
|
||||
// RX only.
|
||||
} else if (rx_length > 0) {
|
||||
start_asynch_rx(twi_info, twi);
|
||||
// Both 'tx_length' and 'rx_length' are 0 - this case may be used
|
||||
// to test if the slave is presentand ready for transfer (by just
|
||||
// sending the address and checking if it is acknowledged).
|
||||
} else {
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
|
||||
if (stop) {
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
|
||||
} else {
|
||||
nrf_twi_task_trigger(twi, NRF_TWI_TASK_SUSPEND);
|
||||
nrf_twi_int_enable(twi, NRF_TWI_INT_SUSPENDED_MASK);
|
||||
}
|
||||
twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
|
||||
}
|
||||
|
||||
nrf_twi_int_enable(twi, NRF_TWI_INT_TXDSENT_MASK |
|
||||
NRF_TWI_INT_RXDREADY_MASK |
|
||||
NRF_TWI_INT_STOPPED_MASK |
|
||||
NRF_TWI_INT_ERROR_MASK);
|
||||
}
|
||||
|
||||
uint32_t i2c_irq_handler_asynch(i2c_t *obj)
|
||||
{
|
||||
twi_info_t *twi_info = TWI_INFO(obj);
|
||||
return (twi_info->events & twi_info->event_mask);
|
||||
return (twi_info->events & twi_info->evt_mask);
|
||||
}
|
||||
|
||||
uint8_t i2c_active(i2c_t *obj)
|
||||
{
|
||||
nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
|
||||
return nrf_drv_twi_is_busy(twi);
|
||||
twi_info_t *twi_info = TWI_INFO(obj);
|
||||
return twi_info->active;
|
||||
}
|
||||
|
||||
void i2c_abort_asynch(i2c_t *obj)
|
||||
{
|
||||
i2c_reset(obj);
|
||||
}
|
||||
|
||||
#endif // DEVICE_I2C_ASYNCH
|
||||
|
||||
#endif // DEVICE_I2C
|
||||
|
|
|
|||
Loading…
Reference in New Issue