MacroRat / MouseCode

Mouse code for the MacroRat

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_NORDIC/TARGET_NRF5_SDK13/i2c_api.c@18:6a4db94011d3, 2017-05-14 (annotated)

Committer:
sahilmgandhi
Date:
Sun May 14 23:18:57 2017 +0000
Revision:
18:6a4db94011d3
Publishing again

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sahilmgandhi 18:6a4db94011d3 1 /*
sahilmgandhi 18:6a4db94011d3 2 * Copyright (c) 2017 Nordic Semiconductor ASA
sahilmgandhi 18:6a4db94011d3 3 * All rights reserved.
sahilmgandhi 18:6a4db94011d3 4 *
sahilmgandhi 18:6a4db94011d3 5 * Redistribution and use in source and binary forms, with or without modification,
sahilmgandhi 18:6a4db94011d3 6 * are permitted provided that the following conditions are met:
sahilmgandhi 18:6a4db94011d3 7 *
sahilmgandhi 18:6a4db94011d3 8 * 1. Redistributions of source code must retain the above copyright notice, this list
sahilmgandhi 18:6a4db94011d3 9 * of conditions and the following disclaimer.
sahilmgandhi 18:6a4db94011d3 10 *
sahilmgandhi 18:6a4db94011d3 11 * 2. Redistributions in binary form, except as embedded into a Nordic Semiconductor ASA
sahilmgandhi 18:6a4db94011d3 12 * integrated circuit in a product or a software update for such product, must reproduce
sahilmgandhi 18:6a4db94011d3 13 * the above copyright notice, this list of conditions and the following disclaimer in
sahilmgandhi 18:6a4db94011d3 14 * the documentation and/or other materials provided with the distribution.
sahilmgandhi 18:6a4db94011d3 15 *
sahilmgandhi 18:6a4db94011d3 16 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its contributors may be
sahilmgandhi 18:6a4db94011d3 17 * used to endorse or promote products derived from this software without specific prior
sahilmgandhi 18:6a4db94011d3 18 * written permission.
sahilmgandhi 18:6a4db94011d3 19 *
sahilmgandhi 18:6a4db94011d3 20 * 4. This software, with or without modification, must only be used with a
sahilmgandhi 18:6a4db94011d3 21 * Nordic Semiconductor ASA integrated circuit.
sahilmgandhi 18:6a4db94011d3 22 *
sahilmgandhi 18:6a4db94011d3 23 * 5. Any software provided in binary or object form under this license must not be reverse
sahilmgandhi 18:6a4db94011d3 24 * engineered, decompiled, modified and/or disassembled.
sahilmgandhi 18:6a4db94011d3 25 *
sahilmgandhi 18:6a4db94011d3 26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
sahilmgandhi 18:6a4db94011d3 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
sahilmgandhi 18:6a4db94011d3 28 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
sahilmgandhi 18:6a4db94011d3 29 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
sahilmgandhi 18:6a4db94011d3 30 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
sahilmgandhi 18:6a4db94011d3 31 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
sahilmgandhi 18:6a4db94011d3 32 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
sahilmgandhi 18:6a4db94011d3 33 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
sahilmgandhi 18:6a4db94011d3 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
sahilmgandhi 18:6a4db94011d3 35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
sahilmgandhi 18:6a4db94011d3 36 *
sahilmgandhi 18:6a4db94011d3 37 */
sahilmgandhi 18:6a4db94011d3 38
sahilmgandhi 18:6a4db94011d3 39
sahilmgandhi 18:6a4db94011d3 40 #include "i2c_api.h"
sahilmgandhi 18:6a4db94011d3 41
sahilmgandhi 18:6a4db94011d3 42 #if DEVICE_I2C
sahilmgandhi 18:6a4db94011d3 43
sahilmgandhi 18:6a4db94011d3 44 #include "mbed_assert.h"
sahilmgandhi 18:6a4db94011d3 45 #include "mbed_error.h"
sahilmgandhi 18:6a4db94011d3 46 #include "nrf_twi.h"
sahilmgandhi 18:6a4db94011d3 47 #include "nrf_drv_common.h"
sahilmgandhi 18:6a4db94011d3 48 #include "sdk_config.h"
sahilmgandhi 18:6a4db94011d3 49 #include "app_util_platform.h"
sahilmgandhi 18:6a4db94011d3 50 #include "nrf_gpio.h"
sahilmgandhi 18:6a4db94011d3 51 #include "nrf_delay.h"
sahilmgandhi 18:6a4db94011d3 52
sahilmgandhi 18:6a4db94011d3 53 // An arbitrary value used as the counter in loops waiting for given event
sahilmgandhi 18:6a4db94011d3 54 // (e.g. STOPPED), needed to avoid infinite loops (and not involve any timers
sahilmgandhi 18:6a4db94011d3 55 // or tickers).
sahilmgandhi 18:6a4db94011d3 56 #define TIMEOUT_VALUE 1000
sahilmgandhi 18:6a4db94011d3 57
sahilmgandhi 18:6a4db94011d3 58 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 59 #define TWI_IDX(obj) ((obj)->i2c.twi_idx)
sahilmgandhi 18:6a4db94011d3 60 #else
sahilmgandhi 18:6a4db94011d3 61 #define TWI_IDX(obj) ((obj)->twi_idx)
sahilmgandhi 18:6a4db94011d3 62 #endif
sahilmgandhi 18:6a4db94011d3 63 #define TWI_INFO(obj) (&m_twi_info[TWI_IDX(obj)])
sahilmgandhi 18:6a4db94011d3 64
sahilmgandhi 18:6a4db94011d3 65 #define TWI0_INSTANCE_INDEX 0
sahilmgandhi 18:6a4db94011d3 66 #define TWI1_INSTANCE_INDEX TWI0_INSTANCE_INDEX+TWI0_ENABLED
sahilmgandhi 18:6a4db94011d3 67
sahilmgandhi 18:6a4db94011d3 68 typedef struct {
sahilmgandhi 18:6a4db94011d3 69 bool initialized;
sahilmgandhi 18:6a4db94011d3 70 uint32_t pselsda;
sahilmgandhi 18:6a4db94011d3 71 uint32_t pselscl;
sahilmgandhi 18:6a4db94011d3 72 nrf_twi_frequency_t frequency;
sahilmgandhi 18:6a4db94011d3 73 bool start_twi;
sahilmgandhi 18:6a4db94011d3 74
sahilmgandhi 18:6a4db94011d3 75 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 76 volatile bool active;
sahilmgandhi 18:6a4db94011d3 77 uint8_t const *tx;
sahilmgandhi 18:6a4db94011d3 78 size_t tx_length;
sahilmgandhi 18:6a4db94011d3 79 uint8_t *rx;
sahilmgandhi 18:6a4db94011d3 80 size_t rx_length;
sahilmgandhi 18:6a4db94011d3 81 bool stop;
sahilmgandhi 18:6a4db94011d3 82
sahilmgandhi 18:6a4db94011d3 83 volatile uint32_t events;
sahilmgandhi 18:6a4db94011d3 84 void (*handler)(void);
sahilmgandhi 18:6a4db94011d3 85 uint32_t evt_mask;
sahilmgandhi 18:6a4db94011d3 86 #endif // DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 87 } twi_info_t;
sahilmgandhi 18:6a4db94011d3 88 static twi_info_t m_twi_info[TWI_COUNT];
sahilmgandhi 18:6a4db94011d3 89
sahilmgandhi 18:6a4db94011d3 90 static NRF_TWI_Type * const m_twi_instances[TWI_COUNT] = {
sahilmgandhi 18:6a4db94011d3 91 #if TWI0_ENABLED
sahilmgandhi 18:6a4db94011d3 92 NRF_TWI0,
sahilmgandhi 18:6a4db94011d3 93 #endif
sahilmgandhi 18:6a4db94011d3 94 #if TWI1_ENABLED
sahilmgandhi 18:6a4db94011d3 95 NRF_TWI1,
sahilmgandhi 18:6a4db94011d3 96 #endif
sahilmgandhi 18:6a4db94011d3 97 };
sahilmgandhi 18:6a4db94011d3 98
sahilmgandhi 18:6a4db94011d3 99 void SPI0_TWI0_IRQHandler(void);
sahilmgandhi 18:6a4db94011d3 100 void SPI1_TWI1_IRQHandler(void);
sahilmgandhi 18:6a4db94011d3 101
sahilmgandhi 18:6a4db94011d3 102 static const peripheral_handler_desc_t twi_handlers[TWI_COUNT] =
sahilmgandhi 18:6a4db94011d3 103 {
sahilmgandhi 18:6a4db94011d3 104 #if TWI0_ENABLED
sahilmgandhi 18:6a4db94011d3 105 {
sahilmgandhi 18:6a4db94011d3 106 SPI0_TWI0_IRQn,
sahilmgandhi 18:6a4db94011d3 107 (uint32_t) SPI0_TWI0_IRQHandler
sahilmgandhi 18:6a4db94011d3 108 },
sahilmgandhi 18:6a4db94011d3 109 #endif
sahilmgandhi 18:6a4db94011d3 110 #if TWI1_ENABLED
sahilmgandhi 18:6a4db94011d3 111 {
sahilmgandhi 18:6a4db94011d3 112 SPI1_TWI1_IRQn,
sahilmgandhi 18:6a4db94011d3 113 (uint32_t) SPI1_TWI1_IRQHandler
sahilmgandhi 18:6a4db94011d3 114 }
sahilmgandhi 18:6a4db94011d3 115 #endif
sahilmgandhi 18:6a4db94011d3 116 };
sahilmgandhi 18:6a4db94011d3 117 #ifdef NRF51
sahilmgandhi 18:6a4db94011d3 118 #define TWI_IRQ_PRIORITY APP_IRQ_PRIORITY_LOW
sahilmgandhi 18:6a4db94011d3 119 #elif defined(NRF52) || defined(NRF52840_XXAA)
sahilmgandhi 18:6a4db94011d3 120 #define TWI_IRQ_PRIORITY APP_IRQ_PRIORITY_LOWEST
sahilmgandhi 18:6a4db94011d3 121 #endif
sahilmgandhi 18:6a4db94011d3 122
sahilmgandhi 18:6a4db94011d3 123
sahilmgandhi 18:6a4db94011d3 124 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 125 static void start_asynch_rx(twi_info_t *twi_info, NRF_TWI_Type *twi)
sahilmgandhi 18:6a4db94011d3 126 {
sahilmgandhi 18:6a4db94011d3 127 if (twi_info->rx_length == 1 && twi_info->stop)
sahilmgandhi 18:6a4db94011d3 128 {
sahilmgandhi 18:6a4db94011d3 129 nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_STOP_MASK);
sahilmgandhi 18:6a4db94011d3 130 }
sahilmgandhi 18:6a4db94011d3 131 else
sahilmgandhi 18:6a4db94011d3 132 {
sahilmgandhi 18:6a4db94011d3 133 nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_SUSPEND_MASK);
sahilmgandhi 18:6a4db94011d3 134 }
sahilmgandhi 18:6a4db94011d3 135 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTRX);
sahilmgandhi 18:6a4db94011d3 136 }
sahilmgandhi 18:6a4db94011d3 137
sahilmgandhi 18:6a4db94011d3 138 static void twi_irq_handler(uint8_t instance_idx)
sahilmgandhi 18:6a4db94011d3 139 {
sahilmgandhi 18:6a4db94011d3 140 twi_info_t *twi_info = &m_twi_info[instance_idx];
sahilmgandhi 18:6a4db94011d3 141
sahilmgandhi 18:6a4db94011d3 142 NRF_TWI_Type *twi = m_twi_instances[instance_idx];
sahilmgandhi 18:6a4db94011d3 143 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_ERROR))
sahilmgandhi 18:6a4db94011d3 144 {
sahilmgandhi 18:6a4db94011d3 145 nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
sahilmgandhi 18:6a4db94011d3 146
sahilmgandhi 18:6a4db94011d3 147 // In case of an error, force STOP.
sahilmgandhi 18:6a4db94011d3 148 // The current transfer may be suspended (if it is RX), so it must be
sahilmgandhi 18:6a4db94011d3 149 // resumed before the STOP task is triggered.
sahilmgandhi 18:6a4db94011d3 150 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 151 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
sahilmgandhi 18:6a4db94011d3 152
sahilmgandhi 18:6a4db94011d3 153 uint32_t errorsrc = nrf_twi_errorsrc_get_and_clear(twi);
sahilmgandhi 18:6a4db94011d3 154 twi_info->events |= I2C_EVENT_ERROR;
sahilmgandhi 18:6a4db94011d3 155 if (errorsrc & NRF_TWI_ERROR_ADDRESS_NACK)
sahilmgandhi 18:6a4db94011d3 156 {
sahilmgandhi 18:6a4db94011d3 157 twi_info->events |= I2C_EVENT_ERROR_NO_SLAVE;
sahilmgandhi 18:6a4db94011d3 158 }
sahilmgandhi 18:6a4db94011d3 159 if (errorsrc & NRF_TWI_ERROR_DATA_NACK)
sahilmgandhi 18:6a4db94011d3 160 {
sahilmgandhi 18:6a4db94011d3 161 twi_info->events |= I2C_EVENT_TRANSFER_EARLY_NACK;
sahilmgandhi 18:6a4db94011d3 162 }
sahilmgandhi 18:6a4db94011d3 163 }
sahilmgandhi 18:6a4db94011d3 164
sahilmgandhi 18:6a4db94011d3 165 bool finished = false;
sahilmgandhi 18:6a4db94011d3 166
sahilmgandhi 18:6a4db94011d3 167 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_TXDSENT))
sahilmgandhi 18:6a4db94011d3 168 {
sahilmgandhi 18:6a4db94011d3 169 nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
sahilmgandhi 18:6a4db94011d3 170
sahilmgandhi 18:6a4db94011d3 171 MBED_ASSERT(twi_info->tx_length > 0);
sahilmgandhi 18:6a4db94011d3 172 --(twi_info->tx_length);
sahilmgandhi 18:6a4db94011d3 173 // Send next byte if there is still something to be sent.
sahilmgandhi 18:6a4db94011d3 174 if (twi_info->tx_length > 0)
sahilmgandhi 18:6a4db94011d3 175 {
sahilmgandhi 18:6a4db94011d3 176 nrf_twi_txd_set(twi, *(twi_info->tx));
sahilmgandhi 18:6a4db94011d3 177 ++(twi_info->tx);
sahilmgandhi 18:6a4db94011d3 178 // It TX is done, start RX if requested.
sahilmgandhi 18:6a4db94011d3 179 }
sahilmgandhi 18:6a4db94011d3 180 else if (twi_info->rx_length > 0)
sahilmgandhi 18:6a4db94011d3 181 {
sahilmgandhi 18:6a4db94011d3 182 start_asynch_rx(twi_info, twi);
sahilmgandhi 18:6a4db94011d3 183 // If there is nothing more to do, finalize the transfer.
sahilmgandhi 18:6a4db94011d3 184 }
sahilmgandhi 18:6a4db94011d3 185 else
sahilmgandhi 18:6a4db94011d3 186 {
sahilmgandhi 18:6a4db94011d3 187 if (twi_info->stop)
sahilmgandhi 18:6a4db94011d3 188 {
sahilmgandhi 18:6a4db94011d3 189 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
sahilmgandhi 18:6a4db94011d3 190 }
sahilmgandhi 18:6a4db94011d3 191 else
sahilmgandhi 18:6a4db94011d3 192 {
sahilmgandhi 18:6a4db94011d3 193 nrf_twi_task_trigger(twi, NRF_TWI_TASK_SUSPEND);
sahilmgandhi 18:6a4db94011d3 194 finished = true;
sahilmgandhi 18:6a4db94011d3 195 }
sahilmgandhi 18:6a4db94011d3 196 twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
sahilmgandhi 18:6a4db94011d3 197 }
sahilmgandhi 18:6a4db94011d3 198 }
sahilmgandhi 18:6a4db94011d3 199
sahilmgandhi 18:6a4db94011d3 200 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_RXDREADY))
sahilmgandhi 18:6a4db94011d3 201 {
sahilmgandhi 18:6a4db94011d3 202 nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
sahilmgandhi 18:6a4db94011d3 203
sahilmgandhi 18:6a4db94011d3 204 MBED_ASSERT(twi_info->rx_length > 0);
sahilmgandhi 18:6a4db94011d3 205 *(twi_info->rx) = nrf_twi_rxd_get(twi);
sahilmgandhi 18:6a4db94011d3 206 ++(twi_info->rx);
sahilmgandhi 18:6a4db94011d3 207 --(twi_info->rx_length);
sahilmgandhi 18:6a4db94011d3 208
sahilmgandhi 18:6a4db94011d3 209 if (twi_info->rx_length > 0)
sahilmgandhi 18:6a4db94011d3 210 {
sahilmgandhi 18:6a4db94011d3 211 // If more bytes should be received, resume the transfer
sahilmgandhi 18:6a4db94011d3 212 // (in case the stop condition should be generated after the next
sahilmgandhi 18:6a4db94011d3 213 // byte, change the shortcuts configuration first).
sahilmgandhi 18:6a4db94011d3 214 if (twi_info->rx_length == 1 && twi_info->stop)
sahilmgandhi 18:6a4db94011d3 215 {
sahilmgandhi 18:6a4db94011d3 216 nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_STOP_MASK);
sahilmgandhi 18:6a4db94011d3 217 }
sahilmgandhi 18:6a4db94011d3 218 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 219 }
sahilmgandhi 18:6a4db94011d3 220 else
sahilmgandhi 18:6a4db94011d3 221 {
sahilmgandhi 18:6a4db94011d3 222 // If all requested bytes were received, finalize the transfer.
sahilmgandhi 18:6a4db94011d3 223 finished = true;
sahilmgandhi 18:6a4db94011d3 224 twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
sahilmgandhi 18:6a4db94011d3 225 }
sahilmgandhi 18:6a4db94011d3 226 }
sahilmgandhi 18:6a4db94011d3 227
sahilmgandhi 18:6a4db94011d3 228 if (finished ||
sahilmgandhi 18:6a4db94011d3 229 nrf_twi_event_check(twi, NRF_TWI_EVENT_STOPPED) ||
sahilmgandhi 18:6a4db94011d3 230 (nrf_twi_int_enable_check(twi, NRF_TWI_INT_SUSPENDED_MASK) &&
sahilmgandhi 18:6a4db94011d3 231 nrf_twi_event_check(twi, NRF_TWI_EVENT_SUSPENDED)))
sahilmgandhi 18:6a4db94011d3 232 {
sahilmgandhi 18:6a4db94011d3 233 // There is no need to clear the STOPPED and SUSPENDED events here,
sahilmgandhi 18:6a4db94011d3 234 // they will no longer generate the interrupt - see below.
sahilmgandhi 18:6a4db94011d3 235
sahilmgandhi 18:6a4db94011d3 236 nrf_twi_shorts_set(twi, 0);
sahilmgandhi 18:6a4db94011d3 237 // Disable all interrupt sources.
sahilmgandhi 18:6a4db94011d3 238 nrf_twi_int_disable(twi, UINT32_MAX);
sahilmgandhi 18:6a4db94011d3 239 twi_info->active = false;
sahilmgandhi 18:6a4db94011d3 240
sahilmgandhi 18:6a4db94011d3 241 if (twi_info->handler)
sahilmgandhi 18:6a4db94011d3 242 {
sahilmgandhi 18:6a4db94011d3 243 twi_info->handler();
sahilmgandhi 18:6a4db94011d3 244 }
sahilmgandhi 18:6a4db94011d3 245 }
sahilmgandhi 18:6a4db94011d3 246 }
sahilmgandhi 18:6a4db94011d3 247
sahilmgandhi 18:6a4db94011d3 248 #if TWI0_ENABLED
sahilmgandhi 18:6a4db94011d3 249 static void irq_handler_twi0(void)
sahilmgandhi 18:6a4db94011d3 250 {
sahilmgandhi 18:6a4db94011d3 251 twi_irq_handler(TWI0_INSTANCE_INDEX);
sahilmgandhi 18:6a4db94011d3 252 }
sahilmgandhi 18:6a4db94011d3 253 #endif
sahilmgandhi 18:6a4db94011d3 254 #if TWI1_ENABLED
sahilmgandhi 18:6a4db94011d3 255 static void irq_handler_twi1(void)
sahilmgandhi 18:6a4db94011d3 256 {
sahilmgandhi 18:6a4db94011d3 257 twi_irq_handler(TWI1_INSTANCE_INDEX);
sahilmgandhi 18:6a4db94011d3 258 }
sahilmgandhi 18:6a4db94011d3 259 #endif
sahilmgandhi 18:6a4db94011d3 260 static nrf_drv_irq_handler_t const m_twi_irq_handlers[TWI_COUNT] =
sahilmgandhi 18:6a4db94011d3 261 {
sahilmgandhi 18:6a4db94011d3 262 #if TWI0_ENABLED
sahilmgandhi 18:6a4db94011d3 263 irq_handler_twi0,
sahilmgandhi 18:6a4db94011d3 264 #endif
sahilmgandhi 18:6a4db94011d3 265 #if TWI1_ENABLED
sahilmgandhi 18:6a4db94011d3 266 irq_handler_twi1,
sahilmgandhi 18:6a4db94011d3 267 #endif
sahilmgandhi 18:6a4db94011d3 268 };
sahilmgandhi 18:6a4db94011d3 269 #endif // DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 270
sahilmgandhi 18:6a4db94011d3 271
sahilmgandhi 18:6a4db94011d3 272 static void configure_twi_pin(uint32_t pin, nrf_gpio_pin_dir_t dir)
sahilmgandhi 18:6a4db94011d3 273 {
sahilmgandhi 18:6a4db94011d3 274 nrf_gpio_cfg(pin,
sahilmgandhi 18:6a4db94011d3 275 dir,
sahilmgandhi 18:6a4db94011d3 276 NRF_GPIO_PIN_INPUT_CONNECT,
sahilmgandhi 18:6a4db94011d3 277 NRF_GPIO_PIN_PULLUP,
sahilmgandhi 18:6a4db94011d3 278 NRF_GPIO_PIN_S0D1,
sahilmgandhi 18:6a4db94011d3 279 NRF_GPIO_PIN_NOSENSE);
sahilmgandhi 18:6a4db94011d3 280 }
sahilmgandhi 18:6a4db94011d3 281
sahilmgandhi 18:6a4db94011d3 282 static void twi_clear_bus(twi_info_t *twi_info)
sahilmgandhi 18:6a4db94011d3 283 {
sahilmgandhi 18:6a4db94011d3 284 // Try to set SDA high, and check if no slave tries to drive it low.
sahilmgandhi 18:6a4db94011d3 285 nrf_gpio_pin_set(twi_info->pselsda);
sahilmgandhi 18:6a4db94011d3 286 configure_twi_pin(twi_info->pselsda, NRF_GPIO_PIN_DIR_OUTPUT);
sahilmgandhi 18:6a4db94011d3 287 // In case SDA is low, make up to 9 cycles on SCL line to help the slave
sahilmgandhi 18:6a4db94011d3 288 // that pulls SDA low release it.
sahilmgandhi 18:6a4db94011d3 289 if (!nrf_gpio_pin_read(twi_info->pselsda))
sahilmgandhi 18:6a4db94011d3 290 {
sahilmgandhi 18:6a4db94011d3 291 nrf_gpio_pin_set(twi_info->pselscl);
sahilmgandhi 18:6a4db94011d3 292 configure_twi_pin(twi_info->pselscl, NRF_GPIO_PIN_DIR_OUTPUT);
sahilmgandhi 18:6a4db94011d3 293 nrf_delay_us(4);
sahilmgandhi 18:6a4db94011d3 294
sahilmgandhi 18:6a4db94011d3 295 for (int i = 0; i < 9; i++)
sahilmgandhi 18:6a4db94011d3 296 {
sahilmgandhi 18:6a4db94011d3 297 if (nrf_gpio_pin_read(twi_info->pselsda))
sahilmgandhi 18:6a4db94011d3 298 {
sahilmgandhi 18:6a4db94011d3 299 break;
sahilmgandhi 18:6a4db94011d3 300 }
sahilmgandhi 18:6a4db94011d3 301 nrf_gpio_pin_clear(twi_info->pselscl);
sahilmgandhi 18:6a4db94011d3 302 nrf_delay_us(4);
sahilmgandhi 18:6a4db94011d3 303 nrf_gpio_pin_set(twi_info->pselscl);
sahilmgandhi 18:6a4db94011d3 304 nrf_delay_us(4);
sahilmgandhi 18:6a4db94011d3 305 }
sahilmgandhi 18:6a4db94011d3 306
sahilmgandhi 18:6a4db94011d3 307 // Finally, generate STOP condition to put the bus into initial state.
sahilmgandhi 18:6a4db94011d3 308 nrf_gpio_pin_clear(twi_info->pselsda);
sahilmgandhi 18:6a4db94011d3 309 nrf_delay_us(4);
sahilmgandhi 18:6a4db94011d3 310 nrf_gpio_pin_set(twi_info->pselsda);
sahilmgandhi 18:6a4db94011d3 311 }
sahilmgandhi 18:6a4db94011d3 312 }
sahilmgandhi 18:6a4db94011d3 313
sahilmgandhi 18:6a4db94011d3 314 void i2c_init(i2c_t *obj, PinName sda, PinName scl)
sahilmgandhi 18:6a4db94011d3 315 {
sahilmgandhi 18:6a4db94011d3 316 int i;
sahilmgandhi 18:6a4db94011d3 317
sahilmgandhi 18:6a4db94011d3 318 for (i = 0; i < TWI_COUNT; ++i)
sahilmgandhi 18:6a4db94011d3 319 {
sahilmgandhi 18:6a4db94011d3 320 if (m_twi_info[i].initialized &&
sahilmgandhi 18:6a4db94011d3 321 m_twi_info[i].pselsda == (uint32_t)sda &&
sahilmgandhi 18:6a4db94011d3 322 m_twi_info[i].pselscl == (uint32_t)scl)
sahilmgandhi 18:6a4db94011d3 323 {
sahilmgandhi 18:6a4db94011d3 324 TWI_IDX(obj) = i;
sahilmgandhi 18:6a4db94011d3 325 TWI_INFO(obj)->frequency = NRF_TWI_FREQ_100K;
sahilmgandhi 18:6a4db94011d3 326 i2c_reset(obj);
sahilmgandhi 18:6a4db94011d3 327 return;
sahilmgandhi 18:6a4db94011d3 328 }
sahilmgandhi 18:6a4db94011d3 329 }
sahilmgandhi 18:6a4db94011d3 330
sahilmgandhi 18:6a4db94011d3 331 for (i = 0; i < TWI_COUNT; ++i)
sahilmgandhi 18:6a4db94011d3 332 {
sahilmgandhi 18:6a4db94011d3 333 if (!m_twi_info[i].initialized)
sahilmgandhi 18:6a4db94011d3 334 {
sahilmgandhi 18:6a4db94011d3 335 TWI_IDX(obj) = i;
sahilmgandhi 18:6a4db94011d3 336
sahilmgandhi 18:6a4db94011d3 337 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 338 twi_info->initialized = true;
sahilmgandhi 18:6a4db94011d3 339 twi_info->pselsda = (uint32_t)sda;
sahilmgandhi 18:6a4db94011d3 340 twi_info->pselscl = (uint32_t)scl;
sahilmgandhi 18:6a4db94011d3 341 twi_info->frequency = NRF_TWI_FREQ_100K;
sahilmgandhi 18:6a4db94011d3 342 twi_info->start_twi = false;
sahilmgandhi 18:6a4db94011d3 343 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 344 twi_info->active = false;
sahilmgandhi 18:6a4db94011d3 345 #endif
sahilmgandhi 18:6a4db94011d3 346
sahilmgandhi 18:6a4db94011d3 347 twi_clear_bus(twi_info);
sahilmgandhi 18:6a4db94011d3 348
sahilmgandhi 18:6a4db94011d3 349 configure_twi_pin(twi_info->pselsda, NRF_GPIO_PIN_DIR_INPUT);
sahilmgandhi 18:6a4db94011d3 350 configure_twi_pin(twi_info->pselscl, NRF_GPIO_PIN_DIR_INPUT);
sahilmgandhi 18:6a4db94011d3 351
sahilmgandhi 18:6a4db94011d3 352 i2c_reset(obj);
sahilmgandhi 18:6a4db94011d3 353
sahilmgandhi 18:6a4db94011d3 354 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 355 nrf_drv_common_per_res_acquire(m_twi_instances[i],
sahilmgandhi 18:6a4db94011d3 356 m_twi_irq_handlers[i]);
sahilmgandhi 18:6a4db94011d3 357 NVIC_SetVector(twi_handlers[i].IRQn, twi_handlers[i].vector);
sahilmgandhi 18:6a4db94011d3 358 nrf_drv_common_irq_enable(twi_handlers[i].IRQn, TWI_IRQ_PRIORITY);
sahilmgandhi 18:6a4db94011d3 359 #endif
sahilmgandhi 18:6a4db94011d3 360
sahilmgandhi 18:6a4db94011d3 361 return;
sahilmgandhi 18:6a4db94011d3 362 }
sahilmgandhi 18:6a4db94011d3 363 }
sahilmgandhi 18:6a4db94011d3 364
sahilmgandhi 18:6a4db94011d3 365 error("No available I2C peripheral\r\n");
sahilmgandhi 18:6a4db94011d3 366 }
sahilmgandhi 18:6a4db94011d3 367
sahilmgandhi 18:6a4db94011d3 368 void i2c_reset(i2c_t *obj)
sahilmgandhi 18:6a4db94011d3 369 {
sahilmgandhi 18:6a4db94011d3 370 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 371 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 372
sahilmgandhi 18:6a4db94011d3 373 nrf_twi_disable(twi);
sahilmgandhi 18:6a4db94011d3 374 nrf_twi_pins_set(twi, twi_info->pselscl, twi_info->pselsda);
sahilmgandhi 18:6a4db94011d3 375 nrf_twi_frequency_set(twi, twi_info->frequency);
sahilmgandhi 18:6a4db94011d3 376 nrf_twi_enable(twi);
sahilmgandhi 18:6a4db94011d3 377 }
sahilmgandhi 18:6a4db94011d3 378
sahilmgandhi 18:6a4db94011d3 379 int i2c_start(i2c_t *obj)
sahilmgandhi 18:6a4db94011d3 380 {
sahilmgandhi 18:6a4db94011d3 381 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 382 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 383 if (twi_info->active)
sahilmgandhi 18:6a4db94011d3 384 {
sahilmgandhi 18:6a4db94011d3 385 return I2C_ERROR_BUS_BUSY;
sahilmgandhi 18:6a4db94011d3 386 }
sahilmgandhi 18:6a4db94011d3 387 #endif
sahilmgandhi 18:6a4db94011d3 388 twi_info->start_twi = true;
sahilmgandhi 18:6a4db94011d3 389
sahilmgandhi 18:6a4db94011d3 390 return 0;
sahilmgandhi 18:6a4db94011d3 391 }
sahilmgandhi 18:6a4db94011d3 392
sahilmgandhi 18:6a4db94011d3 393 int i2c_stop(i2c_t *obj)
sahilmgandhi 18:6a4db94011d3 394 {
sahilmgandhi 18:6a4db94011d3 395 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 396
sahilmgandhi 18:6a4db94011d3 397 // The current transfer may be suspended (if it is RX), so it must be
sahilmgandhi 18:6a4db94011d3 398 // resumed before the STOP task is triggered.
sahilmgandhi 18:6a4db94011d3 399 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 400 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
sahilmgandhi 18:6a4db94011d3 401 uint32_t remaining_time = TIMEOUT_VALUE;
sahilmgandhi 18:6a4db94011d3 402
sahilmgandhi 18:6a4db94011d3 403 do
sahilmgandhi 18:6a4db94011d3 404 {
sahilmgandhi 18:6a4db94011d3 405 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_STOPPED))
sahilmgandhi 18:6a4db94011d3 406 {
sahilmgandhi 18:6a4db94011d3 407 return 0;
sahilmgandhi 18:6a4db94011d3 408 }
sahilmgandhi 18:6a4db94011d3 409 }
sahilmgandhi 18:6a4db94011d3 410 while (--remaining_time);
sahilmgandhi 18:6a4db94011d3 411
sahilmgandhi 18:6a4db94011d3 412 return 1;
sahilmgandhi 18:6a4db94011d3 413 }
sahilmgandhi 18:6a4db94011d3 414
sahilmgandhi 18:6a4db94011d3 415 void i2c_frequency(i2c_t *obj, int hz)
sahilmgandhi 18:6a4db94011d3 416 {
sahilmgandhi 18:6a4db94011d3 417 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 418 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 419
sahilmgandhi 18:6a4db94011d3 420 if (hz < 250000)
sahilmgandhi 18:6a4db94011d3 421 {
sahilmgandhi 18:6a4db94011d3 422 twi_info->frequency = NRF_TWI_FREQ_100K;
sahilmgandhi 18:6a4db94011d3 423 }
sahilmgandhi 18:6a4db94011d3 424 else if (hz < 400000)
sahilmgandhi 18:6a4db94011d3 425 {
sahilmgandhi 18:6a4db94011d3 426 twi_info->frequency = NRF_TWI_FREQ_250K;
sahilmgandhi 18:6a4db94011d3 427 }
sahilmgandhi 18:6a4db94011d3 428 else
sahilmgandhi 18:6a4db94011d3 429 {
sahilmgandhi 18:6a4db94011d3 430 twi_info->frequency = NRF_TWI_FREQ_400K;
sahilmgandhi 18:6a4db94011d3 431 }
sahilmgandhi 18:6a4db94011d3 432 nrf_twi_frequency_set(twi, twi_info->frequency);
sahilmgandhi 18:6a4db94011d3 433 }
sahilmgandhi 18:6a4db94011d3 434
sahilmgandhi 18:6a4db94011d3 435 static uint8_t twi_address(int i2c_address)
sahilmgandhi 18:6a4db94011d3 436 {
sahilmgandhi 18:6a4db94011d3 437 // The TWI peripheral requires 7-bit slave address (without R/W bit).
sahilmgandhi 18:6a4db94011d3 438 return (i2c_address >> 1);
sahilmgandhi 18:6a4db94011d3 439 }
sahilmgandhi 18:6a4db94011d3 440
sahilmgandhi 18:6a4db94011d3 441 static void start_twi_read(NRF_TWI_Type *twi, int address)
sahilmgandhi 18:6a4db94011d3 442 {
sahilmgandhi 18:6a4db94011d3 443 nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
sahilmgandhi 18:6a4db94011d3 444 nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
sahilmgandhi 18:6a4db94011d3 445 nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
sahilmgandhi 18:6a4db94011d3 446 (void)nrf_twi_errorsrc_get_and_clear(twi);
sahilmgandhi 18:6a4db94011d3 447
sahilmgandhi 18:6a4db94011d3 448 nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_SUSPEND_MASK);
sahilmgandhi 18:6a4db94011d3 449
sahilmgandhi 18:6a4db94011d3 450 nrf_twi_address_set(twi, twi_address(address));
sahilmgandhi 18:6a4db94011d3 451 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 452 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTRX);
sahilmgandhi 18:6a4db94011d3 453 }
sahilmgandhi 18:6a4db94011d3 454
sahilmgandhi 18:6a4db94011d3 455 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop)
sahilmgandhi 18:6a4db94011d3 456 {
sahilmgandhi 18:6a4db94011d3 457 // Zero-length RX transfers are not supported. Such transfers cannot
sahilmgandhi 18:6a4db94011d3 458 // be easily achieved with TWI peripheral (some dirty tricks would be
sahilmgandhi 18:6a4db94011d3 459 // required for this), and they are actually useless (TX can be used
sahilmgandhi 18:6a4db94011d3 460 // to check if the address is acknowledged by a slave).
sahilmgandhi 18:6a4db94011d3 461 MBED_ASSERT(length > 0);
sahilmgandhi 18:6a4db94011d3 462
sahilmgandhi 18:6a4db94011d3 463 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 464 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 465 if (twi_info->active)
sahilmgandhi 18:6a4db94011d3 466 {
sahilmgandhi 18:6a4db94011d3 467 return I2C_ERROR_BUS_BUSY;
sahilmgandhi 18:6a4db94011d3 468 }
sahilmgandhi 18:6a4db94011d3 469 #endif
sahilmgandhi 18:6a4db94011d3 470 twi_info->start_twi = false;
sahilmgandhi 18:6a4db94011d3 471
sahilmgandhi 18:6a4db94011d3 472 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 473 start_twi_read(twi, address);
sahilmgandhi 18:6a4db94011d3 474
sahilmgandhi 18:6a4db94011d3 475 int result = length;
sahilmgandhi 18:6a4db94011d3 476
sahilmgandhi 18:6a4db94011d3 477 while (length > 0)
sahilmgandhi 18:6a4db94011d3 478 {
sahilmgandhi 18:6a4db94011d3 479 int byte_read_result = i2c_byte_read(obj, (stop && length == 1));
sahilmgandhi 18:6a4db94011d3 480 if (byte_read_result < 0)
sahilmgandhi 18:6a4db94011d3 481 {
sahilmgandhi 18:6a4db94011d3 482 // When an error occurs, return the number of bytes that have been
sahilmgandhi 18:6a4db94011d3 483 // received successfully.
sahilmgandhi 18:6a4db94011d3 484 result -= length;
sahilmgandhi 18:6a4db94011d3 485 // Force STOP condition.
sahilmgandhi 18:6a4db94011d3 486 stop = 1;
sahilmgandhi 18:6a4db94011d3 487 break;
sahilmgandhi 18:6a4db94011d3 488 }
sahilmgandhi 18:6a4db94011d3 489 *data++ = (uint8_t)byte_read_result;
sahilmgandhi 18:6a4db94011d3 490 --length;
sahilmgandhi 18:6a4db94011d3 491 }
sahilmgandhi 18:6a4db94011d3 492
sahilmgandhi 18:6a4db94011d3 493 if (stop)
sahilmgandhi 18:6a4db94011d3 494 {
sahilmgandhi 18:6a4db94011d3 495 (void)i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 496 }
sahilmgandhi 18:6a4db94011d3 497
sahilmgandhi 18:6a4db94011d3 498 return result;
sahilmgandhi 18:6a4db94011d3 499 }
sahilmgandhi 18:6a4db94011d3 500
sahilmgandhi 18:6a4db94011d3 501 static uint8_t twi_byte_write(NRF_TWI_Type *twi, uint8_t data)
sahilmgandhi 18:6a4db94011d3 502 {
sahilmgandhi 18:6a4db94011d3 503 nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
sahilmgandhi 18:6a4db94011d3 504 nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
sahilmgandhi 18:6a4db94011d3 505
sahilmgandhi 18:6a4db94011d3 506 nrf_twi_txd_set(twi, data);
sahilmgandhi 18:6a4db94011d3 507 uint32_t remaining_time = TIMEOUT_VALUE;
sahilmgandhi 18:6a4db94011d3 508
sahilmgandhi 18:6a4db94011d3 509 do
sahilmgandhi 18:6a4db94011d3 510 {
sahilmgandhi 18:6a4db94011d3 511 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_TXDSENT))
sahilmgandhi 18:6a4db94011d3 512 {
sahilmgandhi 18:6a4db94011d3 513 nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
sahilmgandhi 18:6a4db94011d3 514 return 1; // ACK received
sahilmgandhi 18:6a4db94011d3 515 }
sahilmgandhi 18:6a4db94011d3 516 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_ERROR))
sahilmgandhi 18:6a4db94011d3 517 {
sahilmgandhi 18:6a4db94011d3 518 nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
sahilmgandhi 18:6a4db94011d3 519 return 0; // some error occurred
sahilmgandhi 18:6a4db94011d3 520 }
sahilmgandhi 18:6a4db94011d3 521 }
sahilmgandhi 18:6a4db94011d3 522 while (--remaining_time);
sahilmgandhi 18:6a4db94011d3 523
sahilmgandhi 18:6a4db94011d3 524 return 2; // timeout;
sahilmgandhi 18:6a4db94011d3 525 }
sahilmgandhi 18:6a4db94011d3 526
sahilmgandhi 18:6a4db94011d3 527 static void start_twi_write(NRF_TWI_Type *twi, int address)
sahilmgandhi 18:6a4db94011d3 528 {
sahilmgandhi 18:6a4db94011d3 529 nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
sahilmgandhi 18:6a4db94011d3 530 nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
sahilmgandhi 18:6a4db94011d3 531 nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
sahilmgandhi 18:6a4db94011d3 532 (void)nrf_twi_errorsrc_get_and_clear(twi);
sahilmgandhi 18:6a4db94011d3 533
sahilmgandhi 18:6a4db94011d3 534 nrf_twi_shorts_set(twi, 0);
sahilmgandhi 18:6a4db94011d3 535
sahilmgandhi 18:6a4db94011d3 536 nrf_twi_address_set(twi, twi_address(address));
sahilmgandhi 18:6a4db94011d3 537 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 538 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
sahilmgandhi 18:6a4db94011d3 539 }
sahilmgandhi 18:6a4db94011d3 540
sahilmgandhi 18:6a4db94011d3 541 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop)
sahilmgandhi 18:6a4db94011d3 542 {
sahilmgandhi 18:6a4db94011d3 543 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 544 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 545 if (twi_info->active)
sahilmgandhi 18:6a4db94011d3 546 {
sahilmgandhi 18:6a4db94011d3 547 return I2C_ERROR_BUS_BUSY;
sahilmgandhi 18:6a4db94011d3 548 }
sahilmgandhi 18:6a4db94011d3 549 #endif
sahilmgandhi 18:6a4db94011d3 550 twi_info->start_twi = false;
sahilmgandhi 18:6a4db94011d3 551
sahilmgandhi 18:6a4db94011d3 552 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 553 start_twi_write(twi, address);
sahilmgandhi 18:6a4db94011d3 554
sahilmgandhi 18:6a4db94011d3 555 // Special case - transaction with no data.
sahilmgandhi 18:6a4db94011d3 556 // It can be used to check if a slave acknowledges the address.
sahilmgandhi 18:6a4db94011d3 557 if (length == 0)
sahilmgandhi 18:6a4db94011d3 558 {
sahilmgandhi 18:6a4db94011d3 559 nrf_twi_event_t event;
sahilmgandhi 18:6a4db94011d3 560 if (stop)
sahilmgandhi 18:6a4db94011d3 561 {
sahilmgandhi 18:6a4db94011d3 562 event = NRF_TWI_EVENT_STOPPED;
sahilmgandhi 18:6a4db94011d3 563 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
sahilmgandhi 18:6a4db94011d3 564 }
sahilmgandhi 18:6a4db94011d3 565 else
sahilmgandhi 18:6a4db94011d3 566 {
sahilmgandhi 18:6a4db94011d3 567 event = NRF_TWI_EVENT_SUSPENDED;
sahilmgandhi 18:6a4db94011d3 568 nrf_twi_event_clear(twi, event);
sahilmgandhi 18:6a4db94011d3 569 nrf_twi_task_trigger(twi, NRF_TWI_TASK_SUSPEND);
sahilmgandhi 18:6a4db94011d3 570 }
sahilmgandhi 18:6a4db94011d3 571 uint32_t remaining_time = TIMEOUT_VALUE;
sahilmgandhi 18:6a4db94011d3 572
sahilmgandhi 18:6a4db94011d3 573 do
sahilmgandhi 18:6a4db94011d3 574 {
sahilmgandhi 18:6a4db94011d3 575 if (nrf_twi_event_check(twi, event))
sahilmgandhi 18:6a4db94011d3 576 {
sahilmgandhi 18:6a4db94011d3 577 break;
sahilmgandhi 18:6a4db94011d3 578 }
sahilmgandhi 18:6a4db94011d3 579 }
sahilmgandhi 18:6a4db94011d3 580 while (--remaining_time);
sahilmgandhi 18:6a4db94011d3 581
sahilmgandhi 18:6a4db94011d3 582 uint32_t errorsrc = nrf_twi_errorsrc_get_and_clear(twi);
sahilmgandhi 18:6a4db94011d3 583 if (errorsrc & NRF_TWI_ERROR_ADDRESS_NACK)
sahilmgandhi 18:6a4db94011d3 584 {
sahilmgandhi 18:6a4db94011d3 585 if (!stop)
sahilmgandhi 18:6a4db94011d3 586 {
sahilmgandhi 18:6a4db94011d3 587 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 588 }
sahilmgandhi 18:6a4db94011d3 589 return I2C_ERROR_NO_SLAVE;
sahilmgandhi 18:6a4db94011d3 590 }
sahilmgandhi 18:6a4db94011d3 591
sahilmgandhi 18:6a4db94011d3 592 return (remaining_time ? 0 : I2C_ERROR_BUS_BUSY);
sahilmgandhi 18:6a4db94011d3 593 }
sahilmgandhi 18:6a4db94011d3 594
sahilmgandhi 18:6a4db94011d3 595 int result = length;
sahilmgandhi 18:6a4db94011d3 596
sahilmgandhi 18:6a4db94011d3 597 do
sahilmgandhi 18:6a4db94011d3 598 {
sahilmgandhi 18:6a4db94011d3 599 uint8_t byte_write_result = twi_byte_write(twi, (uint8_t)*data++);
sahilmgandhi 18:6a4db94011d3 600 if (byte_write_result != 1)
sahilmgandhi 18:6a4db94011d3 601 {
sahilmgandhi 18:6a4db94011d3 602 if (byte_write_result == 0)
sahilmgandhi 18:6a4db94011d3 603 {
sahilmgandhi 18:6a4db94011d3 604 // Check what kind of error has been signaled by TWI.
sahilmgandhi 18:6a4db94011d3 605 uint32_t errorsrc = nrf_twi_errorsrc_get_and_clear(twi);
sahilmgandhi 18:6a4db94011d3 606 if (errorsrc & NRF_TWI_ERROR_ADDRESS_NACK)
sahilmgandhi 18:6a4db94011d3 607 {
sahilmgandhi 18:6a4db94011d3 608 result = I2C_ERROR_NO_SLAVE;
sahilmgandhi 18:6a4db94011d3 609 }
sahilmgandhi 18:6a4db94011d3 610 else
sahilmgandhi 18:6a4db94011d3 611 {
sahilmgandhi 18:6a4db94011d3 612 // Some other error - return the number of bytes that
sahilmgandhi 18:6a4db94011d3 613 // have been sent successfully.
sahilmgandhi 18:6a4db94011d3 614 result -= length;
sahilmgandhi 18:6a4db94011d3 615 }
sahilmgandhi 18:6a4db94011d3 616 }
sahilmgandhi 18:6a4db94011d3 617 else
sahilmgandhi 18:6a4db94011d3 618 {
sahilmgandhi 18:6a4db94011d3 619 result = I2C_ERROR_BUS_BUSY;
sahilmgandhi 18:6a4db94011d3 620 }
sahilmgandhi 18:6a4db94011d3 621 // Force STOP condition.
sahilmgandhi 18:6a4db94011d3 622 stop = 1;
sahilmgandhi 18:6a4db94011d3 623 break;
sahilmgandhi 18:6a4db94011d3 624 }
sahilmgandhi 18:6a4db94011d3 625 --length;
sahilmgandhi 18:6a4db94011d3 626 }
sahilmgandhi 18:6a4db94011d3 627 while (length > 0);
sahilmgandhi 18:6a4db94011d3 628
sahilmgandhi 18:6a4db94011d3 629 if (stop)
sahilmgandhi 18:6a4db94011d3 630 {
sahilmgandhi 18:6a4db94011d3 631 (void)i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 632 }
sahilmgandhi 18:6a4db94011d3 633
sahilmgandhi 18:6a4db94011d3 634 return result;
sahilmgandhi 18:6a4db94011d3 635 }
sahilmgandhi 18:6a4db94011d3 636
sahilmgandhi 18:6a4db94011d3 637 int i2c_byte_read(i2c_t *obj, int last)
sahilmgandhi 18:6a4db94011d3 638 {
sahilmgandhi 18:6a4db94011d3 639 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 640
sahilmgandhi 18:6a4db94011d3 641 if (last)
sahilmgandhi 18:6a4db94011d3 642 {
sahilmgandhi 18:6a4db94011d3 643 nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_STOP_MASK);
sahilmgandhi 18:6a4db94011d3 644 }
sahilmgandhi 18:6a4db94011d3 645 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 646
sahilmgandhi 18:6a4db94011d3 647 uint32_t remaining_time = TIMEOUT_VALUE;
sahilmgandhi 18:6a4db94011d3 648
sahilmgandhi 18:6a4db94011d3 649 do
sahilmgandhi 18:6a4db94011d3 650 {
sahilmgandhi 18:6a4db94011d3 651 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_RXDREADY))
sahilmgandhi 18:6a4db94011d3 652 {
sahilmgandhi 18:6a4db94011d3 653 nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
sahilmgandhi 18:6a4db94011d3 654 return nrf_twi_rxd_get(twi);
sahilmgandhi 18:6a4db94011d3 655 }
sahilmgandhi 18:6a4db94011d3 656 if (nrf_twi_event_check(twi, NRF_TWI_EVENT_ERROR))
sahilmgandhi 18:6a4db94011d3 657 {
sahilmgandhi 18:6a4db94011d3 658 nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
sahilmgandhi 18:6a4db94011d3 659 return I2C_ERROR_NO_SLAVE;
sahilmgandhi 18:6a4db94011d3 660 }
sahilmgandhi 18:6a4db94011d3 661 }
sahilmgandhi 18:6a4db94011d3 662 while (--remaining_time);
sahilmgandhi 18:6a4db94011d3 663
sahilmgandhi 18:6a4db94011d3 664 return I2C_ERROR_BUS_BUSY;
sahilmgandhi 18:6a4db94011d3 665 }
sahilmgandhi 18:6a4db94011d3 666
sahilmgandhi 18:6a4db94011d3 667 int i2c_byte_write(i2c_t *obj, int data)
sahilmgandhi 18:6a4db94011d3 668 {
sahilmgandhi 18:6a4db94011d3 669 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 670 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 671 if (twi_info->start_twi)
sahilmgandhi 18:6a4db94011d3 672 {
sahilmgandhi 18:6a4db94011d3 673 twi_info->start_twi = false;
sahilmgandhi 18:6a4db94011d3 674
sahilmgandhi 18:6a4db94011d3 675 if (data & 1)
sahilmgandhi 18:6a4db94011d3 676 {
sahilmgandhi 18:6a4db94011d3 677 start_twi_read(twi, data);
sahilmgandhi 18:6a4db94011d3 678 }
sahilmgandhi 18:6a4db94011d3 679 else
sahilmgandhi 18:6a4db94011d3 680 {
sahilmgandhi 18:6a4db94011d3 681 start_twi_write(twi, data);
sahilmgandhi 18:6a4db94011d3 682 }
sahilmgandhi 18:6a4db94011d3 683 return 1;
sahilmgandhi 18:6a4db94011d3 684 }
sahilmgandhi 18:6a4db94011d3 685 else
sahilmgandhi 18:6a4db94011d3 686 {
sahilmgandhi 18:6a4db94011d3 687 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 688 // 0 - TWI signaled error (NAK is the only possibility here)
sahilmgandhi 18:6a4db94011d3 689 // 1 - ACK received
sahilmgandhi 18:6a4db94011d3 690 // 2 - timeout (clock stretched for too long?)
sahilmgandhi 18:6a4db94011d3 691 return twi_byte_write(twi, (uint8_t)data);
sahilmgandhi 18:6a4db94011d3 692 }
sahilmgandhi 18:6a4db94011d3 693 }
sahilmgandhi 18:6a4db94011d3 694
sahilmgandhi 18:6a4db94011d3 695
sahilmgandhi 18:6a4db94011d3 696 #if DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 697 void i2c_transfer_asynch(i2c_t *obj, const void *tx, size_t tx_length,
sahilmgandhi 18:6a4db94011d3 698 void *rx, size_t rx_length, uint32_t address,
sahilmgandhi 18:6a4db94011d3 699 uint32_t stop, uint32_t handler,
sahilmgandhi 18:6a4db94011d3 700 uint32_t event, DMAUsage hint)
sahilmgandhi 18:6a4db94011d3 701 {
sahilmgandhi 18:6a4db94011d3 702 (void)hint;
sahilmgandhi 18:6a4db94011d3 703
sahilmgandhi 18:6a4db94011d3 704 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 705 if (twi_info->active)
sahilmgandhi 18:6a4db94011d3 706 {
sahilmgandhi 18:6a4db94011d3 707 return;
sahilmgandhi 18:6a4db94011d3 708 }
sahilmgandhi 18:6a4db94011d3 709 twi_info->active = true;
sahilmgandhi 18:6a4db94011d3 710 twi_info->events = 0;
sahilmgandhi 18:6a4db94011d3 711 twi_info->handler = (void (*)(void))handler;
sahilmgandhi 18:6a4db94011d3 712 twi_info->evt_mask = event;
sahilmgandhi 18:6a4db94011d3 713 twi_info->tx_length = tx_length;
sahilmgandhi 18:6a4db94011d3 714 twi_info->tx = tx;
sahilmgandhi 18:6a4db94011d3 715 twi_info->rx_length = rx_length;
sahilmgandhi 18:6a4db94011d3 716 twi_info->rx = rx;
sahilmgandhi 18:6a4db94011d3 717 twi_info->stop = stop;
sahilmgandhi 18:6a4db94011d3 718
sahilmgandhi 18:6a4db94011d3 719 NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
sahilmgandhi 18:6a4db94011d3 720
sahilmgandhi 18:6a4db94011d3 721 nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
sahilmgandhi 18:6a4db94011d3 722 nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
sahilmgandhi 18:6a4db94011d3 723 nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
sahilmgandhi 18:6a4db94011d3 724 nrf_twi_event_clear(twi, NRF_TWI_EVENT_SUSPENDED);
sahilmgandhi 18:6a4db94011d3 725 nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
sahilmgandhi 18:6a4db94011d3 726 (void)nrf_twi_errorsrc_get_and_clear(twi);
sahilmgandhi 18:6a4db94011d3 727
sahilmgandhi 18:6a4db94011d3 728 nrf_twi_address_set(twi, twi_address(address));
sahilmgandhi 18:6a4db94011d3 729 nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
sahilmgandhi 18:6a4db94011d3 730 // TX only, or TX + RX (after a repeated start).
sahilmgandhi 18:6a4db94011d3 731 if (tx_length > 0)
sahilmgandhi 18:6a4db94011d3 732 {
sahilmgandhi 18:6a4db94011d3 733 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
sahilmgandhi 18:6a4db94011d3 734 nrf_twi_txd_set(twi, *(twi_info->tx));
sahilmgandhi 18:6a4db94011d3 735 ++(twi_info->tx);
sahilmgandhi 18:6a4db94011d3 736 // RX only.
sahilmgandhi 18:6a4db94011d3 737 }
sahilmgandhi 18:6a4db94011d3 738 else if (rx_length > 0)
sahilmgandhi 18:6a4db94011d3 739 {
sahilmgandhi 18:6a4db94011d3 740 start_asynch_rx(twi_info, twi);
sahilmgandhi 18:6a4db94011d3 741 // Both 'tx_length' and 'rx_length' are 0 - this case may be used
sahilmgandhi 18:6a4db94011d3 742 // to test if the slave is presentand ready for transfer (by just
sahilmgandhi 18:6a4db94011d3 743 // sending the address and checking if it is acknowledged).
sahilmgandhi 18:6a4db94011d3 744 }
sahilmgandhi 18:6a4db94011d3 745 else
sahilmgandhi 18:6a4db94011d3 746 {
sahilmgandhi 18:6a4db94011d3 747 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
sahilmgandhi 18:6a4db94011d3 748 if (stop)
sahilmgandhi 18:6a4db94011d3 749 {
sahilmgandhi 18:6a4db94011d3 750 nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
sahilmgandhi 18:6a4db94011d3 751 }
sahilmgandhi 18:6a4db94011d3 752 else
sahilmgandhi 18:6a4db94011d3 753 {
sahilmgandhi 18:6a4db94011d3 754 nrf_twi_task_trigger(twi, NRF_TWI_TASK_SUSPEND);
sahilmgandhi 18:6a4db94011d3 755 nrf_twi_int_enable(twi, NRF_TWI_INT_SUSPENDED_MASK);
sahilmgandhi 18:6a4db94011d3 756 }
sahilmgandhi 18:6a4db94011d3 757 twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
sahilmgandhi 18:6a4db94011d3 758 }
sahilmgandhi 18:6a4db94011d3 759
sahilmgandhi 18:6a4db94011d3 760 nrf_twi_int_enable(twi, NRF_TWI_INT_TXDSENT_MASK |
sahilmgandhi 18:6a4db94011d3 761 NRF_TWI_INT_RXDREADY_MASK |
sahilmgandhi 18:6a4db94011d3 762 NRF_TWI_INT_STOPPED_MASK |
sahilmgandhi 18:6a4db94011d3 763 NRF_TWI_INT_ERROR_MASK);
sahilmgandhi 18:6a4db94011d3 764 }
sahilmgandhi 18:6a4db94011d3 765
sahilmgandhi 18:6a4db94011d3 766 uint32_t i2c_irq_handler_asynch(i2c_t *obj)
sahilmgandhi 18:6a4db94011d3 767 {
sahilmgandhi 18:6a4db94011d3 768 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 769 return (twi_info->events & twi_info->evt_mask);
sahilmgandhi 18:6a4db94011d3 770 }
sahilmgandhi 18:6a4db94011d3 771
sahilmgandhi 18:6a4db94011d3 772 uint8_t i2c_active(i2c_t *obj)
sahilmgandhi 18:6a4db94011d3 773 {
sahilmgandhi 18:6a4db94011d3 774 twi_info_t *twi_info = TWI_INFO(obj);
sahilmgandhi 18:6a4db94011d3 775 return twi_info->active;
sahilmgandhi 18:6a4db94011d3 776 }
sahilmgandhi 18:6a4db94011d3 777
sahilmgandhi 18:6a4db94011d3 778 void i2c_abort_asynch(i2c_t *obj)
sahilmgandhi 18:6a4db94011d3 779 {
sahilmgandhi 18:6a4db94011d3 780 i2c_reset(obj);
sahilmgandhi 18:6a4db94011d3 781 }
sahilmgandhi 18:6a4db94011d3 782 #endif // DEVICE_I2C_ASYNCH
sahilmgandhi 18:6a4db94011d3 783
sahilmgandhi 18:6a4db94011d3 784 #endif // DEVICE_I2C