diff options
Diffstat (limited to 'os/hal/ports/NRF5/LLD/TWIv1/hal_i2c_lld.c')
| -rw-r--r-- | os/hal/ports/NRF5/LLD/TWIv1/hal_i2c_lld.c | 467 |
1 files changed, 467 insertions, 0 deletions
diff --git a/os/hal/ports/NRF5/LLD/TWIv1/hal_i2c_lld.c b/os/hal/ports/NRF5/LLD/TWIv1/hal_i2c_lld.c new file mode 100644 index 0000000..a9391dd --- /dev/null +++ b/os/hal/ports/NRF5/LLD/TWIv1/hal_i2c_lld.c @@ -0,0 +1,467 @@ +/*
+ Copyright (C) 2015 Stephen Caudle
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+/**
+ * @file TWIv1/hal_i2c_lld.c
+ * @brief NRF5 I2C subsystem low level driver source.
+ *
+ * @addtogroup I2C
+ * @{
+ */
+
+#include "osal.h"
+#include "hal.h"
+#include "nrf_delay.h"
+
+#if HAL_USE_I2C || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver local definitions. */
+/*===========================================================================*/
+
+/* These macros are needed to see if the slave is stuck and we as master send dummy clock cycles to end its wait */
+#define I2C_HIGH(p) do { IOPORT1->OUTSET = (1UL << (p)); } while(0) /*!< Pulls I2C line high */
+#define I2C_LOW(p) do { IOPORT1->OUTCLR = (1UL << (p)); } while(0) /*!< Pulls I2C line low */
+#define I2C_INPUT(p) do { IOPORT1->DIRCLR = (1UL << (p)); } while(0) /*!< Configures I2C pin as input */
+#define I2C_OUTPUT(p) do { IOPORT1->DIRSET = (1UL << (p)); } while(0) /*!< Configures I2C pin as output */
+
+#define I2C_PIN_CNF(internal_pullup) \
+ ((GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos) \
+ | (GPIO_PIN_CNF_DRIVE_S0D1 << GPIO_PIN_CNF_DRIVE_Pos) \
+ | (((internal_pullup) ? GPIO_PIN_CNF_PULL_Pullup : GPIO_PIN_CNF_PULL_Disabled) << GPIO_PIN_CNF_PULL_Pos) \
+ | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) \
+ | (GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos))
+
+#define I2C_PIN_CNF_CLR(internal_pullup) \
+ ((GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos) \
+ | (GPIO_PIN_CNF_DRIVE_S0D1 << GPIO_PIN_CNF_DRIVE_Pos) \
+ | (((internal_pullup) ? GPIO_PIN_CNF_PULL_Pullup : GPIO_PIN_CNF_PULL_Disabled) << GPIO_PIN_CNF_PULL_Pos) \
+ | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) \
+ | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos))
+
+#if NRF5_I2C_USE_I2C0
+#define I2C_IRQ_NUM SPI0_TWI0_IRQn
+#define I2C_IRQ_PRI NRF5_I2C_I2C0_IRQ_PRIORITY
+#elif NRF5_I2C_USE_I2C1
+#define I2C_IRQ_NUM SPI1_TWI1_IRQn
+#define I2C_IRQ_PRI NRF5_I2C_I2C1_IRQ_PRIORITY
+#endif
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/**
+ * @brief I2C0 driver identifier.
+ */
+#if NRF5_I2C_USE_I2C0 || defined(__DOXYGEN__)
+I2CDriver I2CD1;
+#endif
+
+/**
+ * @brief I2C1 driver identifier.
+ */
+#if NRF5_I2C_USE_I2C1 || defined(__DOXYGEN__)
+I2CDriver I2CD2;
+#endif
+
+uint8_t tx_resume_count;
+uint8_t rx_resume_count;
+uint8_t stop_count;
+
+/*===========================================================================*/
+/* Driver local variables and types. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Function for detecting stuck slaves (SDA = 0 and SCL = 1) and tries to clear the bus.
+ *
+ * @return
+ * @retval false Bus is stuck.
+ * @retval true Bus is clear.
+ */
+static void i2c_clear_bus(I2CDriver *i2cp)
+{
+ const I2CConfig *cfg = i2cp->config;
+ int i;
+
+ IOPORT1->PIN_CNF[cfg->scl_pad] = I2C_PIN_CNF(cfg->scl_pullup);
+ IOPORT1->PIN_CNF[cfg->sda_pad] = I2C_PIN_CNF(cfg->sda_pullup);
+
+ I2C_HIGH(cfg->sda_pad);
+ I2C_HIGH(cfg->scl_pad);
+
+ IOPORT1->PIN_CNF[cfg->scl_pad] = I2C_PIN_CNF_CLR(cfg->scl_pullup);
+ IOPORT1->PIN_CNF[cfg->sda_pad] = I2C_PIN_CNF_CLR(cfg->sda_pullup);
+
+ nrf_delay_us(4);
+
+ for(i = 0; i < 9; i++) {
+ if (palReadPad(IOPORT1, cfg->sda_pad)) {
+ if(i > 0)
+ break;
+ else
+ return;
+ }
+
+ I2C_LOW(cfg->scl_pad);
+ nrf_delay_us(4);
+ I2C_HIGH(cfg->scl_pad);
+ nrf_delay_us(4);
+ }
+
+ I2C_LOW(cfg->sda_pad);
+ nrf_delay_us(4);
+ I2C_HIGH(cfg->sda_pad);
+}
+
+static inline void i2c_setup_shortcut(I2CDriver *i2cp)
+{
+ uint32_t rxbytes = i2cp->rxbytes;
+ uint32_t txbytes = i2cp->txbytes;
+
+ osalDbgAssert(rxbytes + txbytes, "transfer must be greater than zero");
+
+ if (txbytes > 1 || (!txbytes && rxbytes > 1))
+ i2cp->i2c->SHORTS = TWI_SHORTS_BB_SUSPEND_Enabled << TWI_SHORTS_BB_SUSPEND_Pos;
+ else if (((txbytes == 1) && !rxbytes) || ((rxbytes == 1) && !txbytes))
+ i2cp->i2c->SHORTS = TWI_SHORTS_BB_STOP_Enabled << TWI_SHORTS_BB_STOP_Pos;
+ else
+ i2cp->i2c->SHORTS = 0;
+}
+
+#if defined(__GNUC__)
+__attribute__((noinline))
+#endif
+/**
+ * @brief Common IRQ handler.
+ * @note Tries hard to clear all the pending interrupt sources, we don't
+ * want to go through the whole ISR and have another interrupt soon
+ * after.
+ *
+ * @param[in] i2cp pointer to an I2CDriver
+ */
+static void serve_interrupt(I2CDriver *i2cp) {
+
+ NRF_TWI_Type *i2c = i2cp->i2c;
+
+ if(i2c->EVENTS_TXDSENT) {
+
+ i2c->EVENTS_TXDSENT = 0;
+#if CORTEX_MODEL >= 4
+ (void)i2c->EVENTS_TXDSENT;
+#endif
+
+ if(--i2cp->txbytes) {
+
+ i2c->TXD = *i2cp->txptr++;
+ i2c_setup_shortcut(i2cp);
+ i2c->TASKS_RESUME = 1;
+ tx_resume_count++;
+ }
+ else if (i2cp->rxbytes) {
+
+ i2c_setup_shortcut(i2cp);
+ i2c->TASKS_STARTRX = 1;
+ }
+ }
+ if(i2c->EVENTS_RXDREADY) {
+
+ i2c->EVENTS_RXDREADY = 0;
+#if CORTEX_MODEL >= 4
+ (void)i2c->EVENTS_RXDREADY;
+#endif
+
+ *i2cp->rxptr++ = i2c->RXD;
+
+ if(--i2cp->rxbytes) {
+ i2c_setup_shortcut(i2cp);
+ i2c->TASKS_RESUME = 1;
+ rx_resume_count++;
+ }
+ }
+ if(i2c->EVENTS_ERROR) {
+
+ uint32_t err = i2c->ERRORSRC;
+ i2c->EVENTS_ERROR = 0;
+#if CORTEX_MODEL >= 4
+ (void)i2c->EVENTS_ERROR;
+#endif
+ if (err & TWI_ERRORSRC_OVERRUN_Msk)
+ i2cp->errors |= I2C_OVERRUN;
+ if (err & (TWI_ERRORSRC_ANACK_Msk | TWI_ERRORSRC_DNACK_Msk))
+ i2cp->errors |= I2C_ACK_FAILURE;
+
+ i2c->TASKS_STOP = 1;
+ _i2c_wakeup_error_isr(i2cp);
+ } else if(i2c->EVENTS_STOPPED) {
+
+ stop_count++;
+ i2c->EVENTS_STOPPED = 0;
+#if CORTEX_MODEL >= 4
+ (void)i2c->EVENTS_STOPPED;
+#endif
+ _i2c_wakeup_isr(i2cp);
+ }
+}
+
+/*===========================================================================*/
+/* Driver interrupt handlers. */
+/*===========================================================================*/
+
+#if NRF5_I2C_USE_I2C0 || defined(__DOXYGEN__)
+
+OSAL_IRQ_HANDLER(Vector4C) {
+
+ OSAL_IRQ_PROLOGUE();
+ serve_interrupt(&I2CD1);
+ OSAL_IRQ_EPILOGUE();
+}
+
+#endif
+
+#if NRF5_I2C_USE_I2C1 || defined(__DOXYGEN__)
+
+OSAL_IRQ_HANDLER(Vector50) {
+
+ OSAL_IRQ_PROLOGUE();
+ serve_interrupt(&I2CD2);
+ OSAL_IRQ_EPILOGUE();
+}
+
+#endif
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Low level I2C driver initialization.
+ *
+ * @notapi
+ */
+void i2c_lld_init(void) {
+
+#if NRF5_I2C_USE_I2C0
+ i2cObjectInit(&I2CD1);
+ I2CD1.thread = NULL;
+ I2CD1.i2c = NRF_TWI0;
+#endif
+
+#if NRF5_I2C_USE_I2C1
+ i2cObjectInit(&I2CD2);
+ I2CD2.thread = NULL;
+ I2CD2.i2c = NRF_TWI1;
+#endif
+
+}
+
+/**
+ * @brief Configures and activates the I2C peripheral.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+void i2c_lld_start(I2CDriver *i2cp) {
+
+ NRF_TWI_Type *i2c = i2cp->i2c;
+ const I2CConfig *cfg = i2cp->config;
+
+ if (i2cp->state != I2C_STOP)
+ return;
+
+ i2c_clear_bus(i2cp);
+
+ IOPORT1->PIN_CNF[cfg->scl_pad] = I2C_PIN_CNF(cfg->scl_pullup);
+ IOPORT1->PIN_CNF[cfg->sda_pad] = I2C_PIN_CNF(cfg->sda_pullup);
+
+ i2c->EVENTS_RXDREADY = 0;
+ i2c->EVENTS_TXDSENT = 0;
+#if CORTEX_MODEL >= 4
+ (void)i2c->EVENTS_RXDREADY;
+ (void)i2c->EVENTS_TXDSENT;
+#endif
+#if NRF_SERIES == 51
+ i2c->PSELSCL = cfg->scl_pad;
+ i2c->PSELSDA = cfg->sda_pad;
+#else
+ i2c->PSEL.SCL = cfg->scl_pad;
+ i2c->PSEL.SDA = cfg->sda_pad;
+#endif
+
+ switch (cfg->clock) {
+ case 100000:
+ i2c->FREQUENCY = TWI_FREQUENCY_FREQUENCY_K100 << TWI_FREQUENCY_FREQUENCY_Pos;
+ break;
+ case 250000:
+ i2c->FREQUENCY = TWI_FREQUENCY_FREQUENCY_K250 << TWI_FREQUENCY_FREQUENCY_Pos;
+ break;
+ case 400000:
+ i2c->FREQUENCY = TWI_FREQUENCY_FREQUENCY_K400 << TWI_FREQUENCY_FREQUENCY_Pos;
+ break;
+ default:
+ osalDbgAssert(0, "invalid I2C frequency");
+ break;
+ };
+
+ nvicEnableVector(I2C_IRQ_NUM, I2C_IRQ_PRI);
+
+ i2c->INTENSET = TWI_INTENSET_TXDSENT_Msk | TWI_INTENSET_STOPPED_Msk |
+ TWI_INTENSET_ERROR_Msk | TWI_INTENSET_RXDREADY_Msk;
+
+ i2c->ENABLE = TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos;
+}
+
+/**
+ * @brief Deactivates the I2C peripheral.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+void i2c_lld_stop(I2CDriver *i2cp) {
+
+ NRF_TWI_Type *i2c = i2cp->i2c;
+ const I2CConfig *cfg = i2cp->config;
+
+ if (i2cp->state != I2C_STOP) {
+
+ i2c->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
+
+ i2c->INTENCLR = TWI_INTENSET_TXDSENT_Msk | TWI_INTENSET_STOPPED_Msk |
+ TWI_INTENSET_ERROR_Msk | TWI_INTENSET_RXDREADY_Msk;
+
+ nvicDisableVector(I2C_IRQ_NUM);
+
+ IOPORT1->PIN_CNF[cfg->scl_pad] = I2C_PIN_CNF_CLR(cfg->scl_pullup);
+ IOPORT1->PIN_CNF[cfg->sda_pad] = I2C_PIN_CNF_CLR(cfg->sda_pullup);
+ }
+}
+
+static inline msg_t _i2c_txrx_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ const uint8_t *txbuf, size_t txbytes,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout) {
+
+ NRF_TWI_Type *i2c = i2cp->i2c;
+
+ (void)timeout;
+ msg_t msg;
+
+ i2cp->errors = I2C_NO_ERROR;
+ i2cp->addr = addr;
+
+ i2cp->txptr = txbuf;
+ i2cp->txbytes = txbytes;
+
+ i2cp->rxptr = rxbuf;
+ i2cp->rxbytes = rxbytes;
+
+ i2c->ADDRESS = addr;
+
+ tx_resume_count = 0;
+ rx_resume_count = 0;
+ stop_count = 0;
+
+ if (i2cp->txbytes) {
+
+ i2c->TXD = *i2cp->txptr++;
+ i2c_setup_shortcut(i2cp);
+ i2c->TASKS_STARTTX = 1;
+ } else if (i2cp->rxbytes) {
+
+ i2c_setup_shortcut(i2cp);
+ i2c->TASKS_STARTRX = 1;
+ } else {
+
+ osalDbgAssert(0, "no bytes to transfer");
+ }
+
+ msg = osalThreadSuspendTimeoutS(&i2cp->thread, timeout);
+
+ if (msg == MSG_TIMEOUT)
+ i2c->TASKS_STOP = 1;
+
+ return msg;
+}
+
+/**
+ * @brief Receives data via the I2C bus as master.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] addr slave device address
+ * @param[out] rxbuf pointer to the receive buffer
+ * @param[in] rxbytes number of bytes to be received
+ * @param[in] timeout the number of ticks before the operation timeouts,
+ * the following special values are allowed:
+ * - @a TIME_INFINITE no timeout.
+ * .
+ * @return The operation status.
+ * @retval MSG_OK if the function succeeded.
+ * @retval MSG_RESET if one or more I2C errors occurred, the errors can
+ * be retrieved using @p i2cGetErrors().
+ * @retval MSG_TIMEOUT if a timeout occurred before operation end. <b>After a
+ * timeout the driver must be stopped and restarted
+ * because the bus is in an uncertain state</b>.
+ *
+ * @notapi
+ */
+msg_t i2c_lld_master_receive_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout) {
+
+ return _i2c_txrx_timeout(i2cp, addr, NULL, 0, rxbuf, rxbytes, timeout);
+}
+
+/**
+ * @brief Transmits data via the I2C bus as master.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] addr slave device address
+ * @param[in] txbuf pointer to the transmit buffer
+ * @param[in] txbytes number of bytes to be transmitted
+ * @param[out] rxbuf pointer to the receive buffer
+ * @param[in] rxbytes number of bytes to be received
+ * @param[in] timeout the number of ticks before the operation timeouts,
+ * the following special values are allowed:
+ * - @a TIME_INFINITE no timeout.
+ * .
+ * @return The operation status.
+ * @retval MSG_OK if the function succeeded.
+ * @retval MSG_RESET if one or more I2C errors occurred, the errors can
+ * be retrieved using @p i2cGetErrors().
+ * @retval MSG_TIMEOUT if a timeout occurred before operation end. <b>After a
+ * timeout the driver must be stopped and restarted
+ * because the bus is in an uncertain state</b>.
+ *
+ * @notapi
+ */
+msg_t i2c_lld_master_transmit_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ const uint8_t *txbuf, size_t txbytes,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout) {
+
+ return _i2c_txrx_timeout(i2cp, addr, txbuf, txbytes, rxbuf, rxbytes, timeout);
+}
+
+#endif /* HAL_USE_I2C */
+
+/** @} */
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