t
Fork of mbed-dev by
Diff: targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/sercom/usart/usart_interrupt.c
- Revision:
- 15:a81a8d6c1dfe
diff -r d797fbdad187 -r a81a8d6c1dfe targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/sercom/usart/usart_interrupt.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/sercom/usart/usart_interrupt.c Wed Nov 04 16:30:11 2015 +0000 @@ -0,0 +1,668 @@ +/** + * \file + * + * \brief SAM SERCOM USART Asynchronous Driver + * + * Copyright (C) 2012-2015 Atmel Corporation. All rights reserved. + * + * \asf_license_start + * + * \page License + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * 3. The name of Atmel may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * 4. This software may only be redistributed and used in connection with an + * Atmel microcontroller product. + * + * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE + * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR + * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * \asf_license_stop + * + */ +/* + * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a> + */ + +#include "usart_interrupt.h" + +/** + * \internal + * Asynchronous write of a buffer with a given length + * + * \param[in] module Pointer to USART software instance struct + * \param[in] tx_data Pointer to data to be transmitted + * \param[in] length Length of data buffer + * + */ +enum status_code _usart_write_buffer( + struct usart_module *const module, + uint8_t *tx_data, + uint16_t length) +{ + /* Sanity check arguments */ + Assert(module); + Assert(module->hw); + Assert(tx_data); + + /* Get a pointer to the hardware module instance */ + SercomUsart *const usart_hw = &(module->hw->USART); + + system_interrupt_enter_critical_section(); + + /* Check if the USART transmitter is busy */ + if (module->remaining_tx_buffer_length > 0) { + system_interrupt_leave_critical_section(); + return STATUS_BUSY; + } + + /* Write parameters to the device instance */ + module->remaining_tx_buffer_length = length; + + system_interrupt_leave_critical_section(); + + module->tx_buffer_ptr = tx_data; + module->tx_status = STATUS_BUSY; + + /* Enable the Data Register Empty Interrupt */ + usart_hw->INTENSET.reg = SERCOM_USART_INTFLAG_DRE; + + return STATUS_OK; +} + +/** + * \internal + * Asynchronous read of a buffer with a given length + * + * \param[in] module Pointer to USART software instance struct + * \param[in] rx_data Pointer to data to be received + * \param[in] length Length of data buffer + * + */ +enum status_code _usart_read_buffer( + struct usart_module *const module, + uint8_t *rx_data, + uint16_t length) +{ + /* Sanity check arguments */ + Assert(module); + Assert(module->hw); + Assert(rx_data); + + /* Get a pointer to the hardware module instance */ + SercomUsart *const usart_hw = &(module->hw->USART); + + system_interrupt_enter_critical_section(); + + /* Check if the USART receiver is busy */ + if (module->remaining_rx_buffer_length > 0) { + system_interrupt_leave_critical_section(); + return STATUS_BUSY; + } + + /* Set length for the buffer and the pointer, and let + * the interrupt handler do the rest */ + module->remaining_rx_buffer_length = length; + + system_interrupt_leave_critical_section(); + + module->rx_buffer_ptr = rx_data; + module->rx_status = STATUS_BUSY; + + /* Enable the RX Complete Interrupt */ + usart_hw->INTENSET.reg = SERCOM_USART_INTFLAG_RXC; + +#ifdef FEATURE_USART_LIN_SLAVE + /* Enable the break character is received Interrupt */ + if(module->lin_slave_enabled) { + usart_hw->INTENSET.reg = SERCOM_USART_INTFLAG_RXBRK; + } +#endif + +#ifdef FEATURE_USART_START_FRAME_DECTION + /* Enable a start condition is detected Interrupt */ + if(module->start_frame_detection_enabled) { + usart_hw->INTENSET.reg = SERCOM_USART_INTFLAG_RXS; + } +#endif + + return STATUS_OK; +} + +/** + * \brief Registers a callback + * + * Registers a callback function which is implemented by the user. + * + * \note The callback must be enabled by \ref usart_enable_callback, + * in order for the interrupt handler to call it when the conditions for + * the callback type are met. + * + * \param[in] module Pointer to USART software instance struct + * \param[in] callback_func Pointer to callback function + * \param[in] callback_type Callback type given by an enum + * + */ +void usart_register_callback( + struct usart_module *const module, + usart_callback_t callback_func, + enum usart_callback callback_type) +{ + /* Sanity check arguments */ + Assert(module); + Assert(callback_func); + + /* Register callback function */ + module->callback[callback_type] = callback_func; + + /* Set the bit corresponding to the callback_type */ + module->callback_reg_mask |= (1 << callback_type); +} + +/** + * \brief Unregisters a callback + * + * Unregisters a callback function which is implemented by the user. + * + * \param[in,out] module Pointer to USART software instance struct + * \param[in] callback_type Callback type given by an enum + * + */ +void usart_unregister_callback( + struct usart_module *const module, + enum usart_callback callback_type) +{ + /* Sanity check arguments */ + Assert(module); + + /* Unregister callback function */ + module->callback[callback_type] = NULL; + + /* Clear the bit corresponding to the callback_type */ + module->callback_reg_mask &= ~(1 << callback_type); +} + +/** + * \brief Asynchronous write a data + * + * Sets up the driver to write the data given. If registered and enabled, + * a callback function will be called when the transmit is completed. + * + * \param[in] module Pointer to USART software instance struct + * \param[in] tx_data Data to transfer + * + * \returns Status of the operation. + * \retval STATUS_OK If operation was completed + * \retval STATUS_BUSY If operation was not completed, due to the + * USART module being busy + * \retval STATUS_ERR_DENIED If the transmitter is not enabled + */ +enum status_code usart_write_job( + struct usart_module *const module, + const uint16_t *tx_data) +{ + /* Sanity check arguments */ + Assert(module); + Assert(tx_data); + + + /* Check that the transmitter is enabled */ + if (!(module->transmitter_enabled)) { + return STATUS_ERR_DENIED; + } + + /* Call internal write buffer function with length 1 */ + return _usart_write_buffer(module, (uint8_t *)tx_data, 1); +} + +/** + * \brief Asynchronous read a data + * + * Sets up the driver to read data from the USART module to the data + * pointer given. If registered and enabled, a callback will be called + * when the receiving is completed. + * + * \param[in] module Pointer to USART software instance struct + * \param[out] rx_data Pointer to where received data should be put + * + * \returns Status of the operation. + * \retval STATUS_OK If operation was completed + * \retval STATUS_BUSY If operation was not completed + */ +enum status_code usart_read_job( + struct usart_module *const module, + uint16_t *const rx_data) +{ + /* Sanity check arguments */ + Assert(module); + Assert(rx_data); + + /* Call internal read buffer function with length 1 */ + return _usart_read_buffer(module, (uint8_t *)rx_data, 1); +} + +/** + * \brief Asynchronous buffer write + * + * Sets up the driver to write a given buffer over the USART. If registered and + * enabled, a callback function will be called. + * + * \param[in] module Pointer to USART software instance struct + * \param[in] tx_data Pointer do data buffer to transmit + * \param[in] length Length of the data to transmit + * + * \note If using 9-bit data, the array that *tx_data point to should be defined + * as uint16_t array and should be casted to uint8_t* pointer. Because it + * is an address pointer, the highest byte is not discarded. For example: + * \code + #define TX_LEN 3 + uint16_t tx_buf[TX_LEN] = {0x0111, 0x0022, 0x0133}; + usart_write_buffer_job(&module, (uint8_t*)tx_buf, TX_LEN); + \endcode + * + * \returns Status of the operation. + * \retval STATUS_OK If operation was completed successfully. + * \retval STATUS_BUSY If operation was not completed, due to the + * USART module being busy + * \retval STATUS_ERR_INVALID_ARG If operation was not completed, due to invalid + * arguments + * \retval STATUS_ERR_DENIED If the transmitter is not enabled + */ +enum status_code usart_write_buffer_job( + struct usart_module *const module, + uint8_t *tx_data, + uint16_t length) +{ + /* Sanity check arguments */ + Assert(module); + Assert(tx_data); + + if (length == 0) { + return STATUS_ERR_INVALID_ARG; + } + + /* Check that the receiver is enabled */ + if (!(module->transmitter_enabled)) { + return STATUS_ERR_DENIED; + } + + /* Issue internal asynchronous write */ + return _usart_write_buffer(module, tx_data, length); +} + +/** + * \brief Asynchronous buffer read + * + * Sets up the driver to read from the USART to a given buffer. If registered + * and enabled, a callback function will be called. + * + * \param[in] module Pointer to USART software instance struct + * \param[out] rx_data Pointer to data buffer to receive + * \param[in] length Data buffer length + * + * \note If using 9-bit data, the array that *rx_data point to should be defined + * as uint16_t array and should be casted to uint8_t* pointer. Because it + * is an address pointer, the highest byte is not discarded. For example: + * \code + #define RX_LEN 3 + uint16_t rx_buf[RX_LEN] = {0x0,}; + usart_read_buffer_job(&module, (uint8_t*)rx_buf, RX_LEN); + \endcode + * + * \returns Status of the operation. + * \retval STATUS_OK If operation was completed + * \retval STATUS_BUSY If operation was not completed, due to the + * USART module being busy + * \retval STATUS_ERR_INVALID_ARG If operation was not completed, due to invalid + * arguments + * \retval STATUS_ERR_DENIED If the transmitter is not enabled + */ +enum status_code usart_read_buffer_job( + struct usart_module *const module, + uint8_t *rx_data, + uint16_t length) +{ + /* Sanity check arguments */ + Assert(module); + Assert(rx_data); + + if (length == 0) { + return STATUS_ERR_INVALID_ARG; + } + + /* Check that the receiver is enabled */ + if (!(module->receiver_enabled)) { + return STATUS_ERR_DENIED; + } + + /* Issue internal asynchronous read */ + return _usart_read_buffer(module, rx_data, length); +} + +/** + * \brief Cancels ongoing read/write operation + * + * Cancels the ongoing read/write operation modifying parameters in the + * USART software struct. + * + * \param[in] module Pointer to USART software instance struct + * \param[in] transceiver_type Transfer type to cancel + */ +void usart_abort_job( + struct usart_module *const module, + enum usart_transceiver_type transceiver_type) +{ + /* Sanity check arguments */ + Assert(module); + Assert(module->hw); + + /* Get a pointer to the hardware module instance */ + SercomUsart *const usart_hw = &(module->hw->USART); + + switch(transceiver_type) { + case USART_TRANSCEIVER_RX: + /* Clear the interrupt flag in order to prevent the receive + * complete callback to fire */ + usart_hw->INTFLAG.reg = SERCOM_USART_INTFLAG_RXC; + + /* Clear the software reception buffer */ + module->remaining_rx_buffer_length = 0; + + break; + + case USART_TRANSCEIVER_TX: + /* Clear the interrupt flag in order to prevent the receive + * complete callback to fire */ + usart_hw->INTFLAG.reg = SERCOM_USART_INTFLAG_TXC; + + /* Clear the software reception buffer */ + module->remaining_tx_buffer_length = 0; + + break; + } +} + +/** + * \brief Get status from the ongoing or last asynchronous transfer operation + * + * Returns the error from a given ongoing or last asynchronous transfer operation. + * Either from a read or write transfer. + * + * \param[in] module Pointer to USART software instance struct + * \param[in] transceiver_type Transfer type to check + * + * \return Status of the given job. + * \retval STATUS_OK No error occurred during the last transfer + * \retval STATUS_BUSY A transfer is ongoing + * \retval STATUS_ERR_BAD_DATA The last operation was aborted due to a + * parity error. The transfer could be affected + * by external noise + * \retval STATUS_ERR_BAD_FORMAT The last operation was aborted due to a + * frame error + * \retval STATUS_ERR_OVERFLOW The last operation was aborted due to a + * buffer overflow + * \retval STATUS_ERR_INVALID_ARG An invalid transceiver enum given + */ +enum status_code usart_get_job_status( + struct usart_module *const module, + enum usart_transceiver_type transceiver_type) +{ + /* Sanity check arguments */ + Assert(module); + + /* Variable for status code */ + enum status_code status_code; + + switch(transceiver_type) { + case USART_TRANSCEIVER_RX: + status_code = module->rx_status; + break; + + case USART_TRANSCEIVER_TX: + status_code = module->tx_status; + break; + + default: + status_code = STATUS_ERR_INVALID_ARG; + break; + } + + return status_code; +} + +/** + * \internal + * Handles interrupts as they occur, and it will run callback functions + * which are registered and enabled. + * + * \param[in] instance ID of the SERCOM instance calling the interrupt + * handler. + */ +void _usart_interrupt_handler( + uint8_t instance) +{ + /* Temporary variables */ + uint16_t interrupt_status; + uint16_t callback_status; + uint8_t error_code; + + + /* Get device instance from the look-up table */ + struct usart_module *module + = (struct usart_module *)_sercom_instances[instance]; + + /* Pointer to the hardware module instance */ + SercomUsart *const usart_hw + = &(module->hw->USART); + + /* Wait for the synchronization to complete */ + _usart_wait_for_sync(module); + + /* Read and mask interrupt flag register */ + interrupt_status = usart_hw->INTFLAG.reg; + interrupt_status &= usart_hw->INTENSET.reg; + callback_status = module->callback_reg_mask & + module->callback_enable_mask; + + /* Check if a DATA READY interrupt has occurred, + * and if there is more to transfer */ + if (interrupt_status & SERCOM_USART_INTFLAG_DRE) { + if (module->remaining_tx_buffer_length) { + /* Write value will be at least 8-bits long */ + uint16_t data_to_send = *(module->tx_buffer_ptr); + /* Increment 8-bit pointer */ + (module->tx_buffer_ptr)++; + + if (module->character_size == USART_CHARACTER_SIZE_9BIT) { + data_to_send |= (*(module->tx_buffer_ptr) << 8); + /* Increment 8-bit pointer */ + (module->tx_buffer_ptr)++; + } + /* Write the data to send */ + usart_hw->DATA.reg = (data_to_send & SERCOM_USART_DATA_MASK); + + if (--(module->remaining_tx_buffer_length) == 0) { + /* Disable the Data Register Empty Interrupt */ + usart_hw->INTENCLR.reg = SERCOM_USART_INTFLAG_DRE; + /* Enable Transmission Complete interrupt */ + usart_hw->INTENSET.reg = SERCOM_USART_INTFLAG_TXC; + + } + } else { + usart_hw->INTENCLR.reg = SERCOM_USART_INTFLAG_DRE; + } + + /* Check if the Transmission Complete interrupt has occurred and + * that the transmit buffer is empty */ + } + + if (interrupt_status & SERCOM_USART_INTFLAG_TXC) { + + /* Disable TX Complete Interrupt, and set STATUS_OK */ + usart_hw->INTENCLR.reg = SERCOM_USART_INTFLAG_TXC; + module->tx_status = STATUS_OK; + + /* Run callback if registered and enabled */ + if (callback_status & (1 << USART_CALLBACK_BUFFER_TRANSMITTED)) { + (*(module->callback[USART_CALLBACK_BUFFER_TRANSMITTED]))(module); + } + + /* Check if the Receive Complete interrupt has occurred, and that + * there's more data to receive */ + } + + if (interrupt_status & SERCOM_USART_INTFLAG_RXC) { + + if (module->remaining_rx_buffer_length) { + /* Read out the status code and mask away all but the 4 LSBs*/ + error_code = (uint8_t)(usart_hw->STATUS.reg & SERCOM_USART_STATUS_MASK); +#if !SAMD20 + /* CTS status should not be considered as an error */ + if(error_code & SERCOM_USART_STATUS_CTS) { + error_code &= ~SERCOM_USART_STATUS_CTS; + } +#endif +#ifdef FEATURE_USART_LIN_MASTER + /* TXE status should not be considered as an error */ + if(error_code & SERCOM_USART_STATUS_TXE) { + error_code &= ~SERCOM_USART_STATUS_TXE; + } +#endif + /* Check if an error has occurred during the receiving */ + if (error_code) { + /* Check which error occurred */ + if (error_code & SERCOM_USART_STATUS_FERR) { + /* Store the error code and clear flag by writing 1 to it */ + module->rx_status = STATUS_ERR_BAD_FORMAT; + usart_hw->STATUS.reg |= SERCOM_USART_STATUS_FERR; + } else if (error_code & SERCOM_USART_STATUS_BUFOVF) { + /* Store the error code and clear flag by writing 1 to it */ + module->rx_status = STATUS_ERR_OVERFLOW; + usart_hw->STATUS.reg |= SERCOM_USART_STATUS_BUFOVF; + } else if (error_code & SERCOM_USART_STATUS_PERR) { + /* Store the error code and clear flag by writing 1 to it */ + module->rx_status = STATUS_ERR_BAD_DATA; + usart_hw->STATUS.reg |= SERCOM_USART_STATUS_PERR; + } +#ifdef FEATURE_USART_LIN_SLAVE + else if (error_code & SERCOM_USART_STATUS_ISF) { + /* Store the error code and clear flag by writing 1 to it */ + module->rx_status = STATUS_ERR_PROTOCOL; + usart_hw->STATUS.reg |= SERCOM_USART_STATUS_ISF; + } +#endif +#ifdef FEATURE_USART_COLLISION_DECTION + else if (error_code & SERCOM_USART_STATUS_COLL) { + /* Store the error code and clear flag by writing 1 to it */ + module->rx_status = STATUS_ERR_PACKET_COLLISION; + usart_hw->STATUS.reg |= SERCOM_USART_STATUS_COLL; + } +#endif + + /* Run callback if registered and enabled */ + if (callback_status + & (1 << USART_CALLBACK_ERROR)) { + (*(module->callback[USART_CALLBACK_ERROR]))(module); + } + + } else { + + /* Read current packet from DATA register, + * increment buffer pointer and decrement buffer length */ + uint16_t received_data = (usart_hw->DATA.reg & SERCOM_USART_DATA_MASK); + + /* Read value will be at least 8-bits long */ + *(module->rx_buffer_ptr) = received_data; + /* Increment 8-bit pointer */ + module->rx_buffer_ptr += 1; + + if (module->character_size == USART_CHARACTER_SIZE_9BIT) { + /* 9-bit data, write next received byte to the buffer */ + *(module->rx_buffer_ptr) = (received_data >> 8); + /* Increment 8-bit pointer */ + module->rx_buffer_ptr += 1; + } + + /* Check if the last character have been received */ + if(--(module->remaining_rx_buffer_length) == 0) { + /* Disable RX Complete Interrupt, + * and set STATUS_OK */ + usart_hw->INTENCLR.reg = SERCOM_USART_INTFLAG_RXC; + module->rx_status = STATUS_OK; + + /* Run callback if registered and enabled */ + if (callback_status + & (1 << USART_CALLBACK_BUFFER_RECEIVED)) { + (*(module->callback[USART_CALLBACK_BUFFER_RECEIVED]))(module); + } + } + } + } else { + /* This should not happen. Disable Receive Complete interrupt. */ + usart_hw->INTENCLR.reg = SERCOM_USART_INTFLAG_RXC; + } + } + +#ifdef FEATURE_USART_HARDWARE_FLOW_CONTROL + if (interrupt_status & SERCOM_USART_INTFLAG_CTSIC) { + /* Disable interrupts */ + usart_hw->INTENCLR.reg = SERCOM_USART_INTENCLR_CTSIC; + /* Clear interrupt flag */ + usart_hw->INTFLAG.reg = SERCOM_USART_INTFLAG_CTSIC; + + /* Run callback if registered and enabled */ + if (callback_status & (1 << USART_CALLBACK_CTS_INPUT_CHANGE)) { + (*(module->callback[USART_CALLBACK_CTS_INPUT_CHANGE]))(module); + } + } +#endif + +#ifdef FEATURE_USART_LIN_SLAVE + if (interrupt_status & SERCOM_USART_INTFLAG_RXBRK) { + /* Disable interrupts */ + usart_hw->INTENCLR.reg = SERCOM_USART_INTENCLR_RXBRK; + /* Clear interrupt flag */ + usart_hw->INTFLAG.reg = SERCOM_USART_INTFLAG_RXBRK; + + /* Run callback if registered and enabled */ + if (callback_status & (1 << USART_CALLBACK_BREAK_RECEIVED)) { + (*(module->callback[USART_CALLBACK_BREAK_RECEIVED]))(module); + } + } +#endif + +#ifdef FEATURE_USART_START_FRAME_DECTION + if (interrupt_status & SERCOM_USART_INTFLAG_RXS) { + /* Disable interrupts */ + usart_hw->INTENCLR.reg = SERCOM_USART_INTENCLR_RXS; + /* Clear interrupt flag */ + usart_hw->INTFLAG.reg = SERCOM_USART_INTFLAG_RXS; + + /* Run callback if registered and enabled */ + if (callback_status & (1 << USART_CALLBACK_START_RECEIVED)) { + (*(module->callback[USART_CALLBACK_START_RECEIVED]))(module); + } + } +#endif +} +