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Diffstat (limited to 'thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/hci/hci_transport.c')
| -rw-r--r-- | thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/hci/hci_transport.c | 808 |
1 files changed, 808 insertions, 0 deletions
diff --git a/thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/hci/hci_transport.c b/thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/hci/hci_transport.c new file mode 100644 index 0000000..f4d6c02 --- /dev/null +++ b/thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/hci/hci_transport.c @@ -0,0 +1,808 @@ +/** + * Copyright (c) 2013 - 2018, Nordic Semiconductor ASA + * + * All rights reserved. + * + * 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, except as embedded into a Nordic + * Semiconductor ASA integrated circuit in a product or a software update for + * such product, 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. Neither the name of Nordic Semiconductor ASA nor the names of its + * contributors may be used to endorse or promote products derived from this + * software without specific prior written permission. + * + * 4. This software, with or without modification, must only be used with a + * Nordic Semiconductor ASA integrated circuit. + * + * 5. Any software provided in binary form under this license must not be reverse + * engineered, decompiled, modified and/or disassembled. + * + * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS + * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS 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. + * + */ +#include "sdk_common.h" +#if NRF_MODULE_ENABLED(HCI_TRANSPORT) +#include "hci_transport.h" +#include "hci_slip.h" +#include "crc16.h" +#include "hci_mem_pool.h" +#include "app_timer.h" +#include "app_error.h" +#include <stdio.h> + +#define PKT_HDR_SIZE 4u /**< Packet header size in number of bytes. */ +#define PKT_CRC_SIZE 2u /**< Packet CRC size in number of bytes. */ +#define PKT_TYPE_VENDOR_SPECIFIC 14u /**< Packet type vendor specific. */ +#define PKT_TYPE_ACK 0 /**< Packet type acknowledgement. */ +#define DATA_INTEGRITY_MASK (1u << 6u) /**< Mask for data integrity bit in the packet header. */ +#define RELIABLE_PKT_MASK (1u << 7u) /**< Mask for reliable packet bit in the packet header. */ +#define INITIAL_ACK_NUMBER_EXPECTED 1u /**< Initial acknowledge number expected. */ +#define INITIAL_ACK_NUMBER_TX INITIAL_ACK_NUMBER_EXPECTED /**< Initial acknowledge number transmitted. */ +#define INVALID_PKT_TYPE 0xFFFFFFFFu /**< Internal invalid packet type value. */ +#define HCI_UART_REG_VALUE_TO_BAUDRATE(BAUDRATE) ((BAUDRATE)/268) /**< Estimated relation between UART baudrate register value and actual baudrate */ +#define MAX_TRANSMISSION_TIME \ + (ROUNDED_DIV((HCI_MAX_PACKET_SIZE_IN_BITS * 1000u), \ + HCI_UART_REG_VALUE_TO_BAUDRATE(HCI_UART_BAUDRATE))) /**< Max transmission time of a single application packet over UART in units of mseconds. */ +#define RETRANSMISSION_TIMEOUT_IN_MS (3u * MAX_TRANSMISSION_TIME) /**< Retransmission timeout for application packet in units of mseconds. */ +#define RETRANSMISSION_TIMEOUT_IN_TICKS APP_TIMER_TICKS(RETRANSMISSION_TIMEOUT_IN_MS) /**< Retransmission timeout for application packet in units of timer ticks. */ +#define MAX_RETRY_COUNT 5u /**< Max retransmission retry count for application packets. */ +#define ACK_BUF_SIZE 5u /**< Length of module internal RX buffer which is big enough to hold an acknowledgement packet. */ + +/**@brief States of the TX state machine. */ +typedef enum +{ + TX_STATE_IDLE, /**< State for: no application transmission packet processing in progress. */ + TX_STATE_PENDING, /**< State for: TX in progress in slip layer and TX-done event is waited for to signal the end of transmission. */ + TX_STATE_ACTIVE /**< State for: application packet has been delivered to slip for transmission and peer transport entity acknowledgement packet is waited for. */ +} tx_state_t; + +/**@brief TX state machine events. */ +typedef enum +{ + TX_EVENT_STATE_ENTRY, /**< Event for: state entry use case. */ + TX_EVENT_SLIP_TX_DONE, /**< Event for: HCI_SLIP_TX_DONE event use case. */ + TX_EVENT_TIMEOUT, /**< Event for: retransmission timeout use case. */ + TX_EVENT_VALID_RX_ACK /**< Event for: valid acknowledgement received for TX packet use case. */ +} tx_event_t; + +static void tx_sm_state_change(tx_state_t new_state); + +static tx_state_t m_tx_state; /**< Current TX state. */ +static hci_transport_tx_done_handler_t m_transport_tx_done_handle; /**< TX done event callback function. */ +static hci_transport_event_handler_t m_transport_event_handle; /**< Event handler callback function. */ +static uint8_t * mp_slip_used_rx_buffer; /**< Reference to RX buffer used by the slip layer. */ +static uint32_t m_packet_expected_seq_number; /**< Sequence number counter of the packet expected to be received . */ +static uint32_t m_packet_transmit_seq_number; /**< Sequence number counter of the transmitted packet for which acknowledgement packet is waited for. */ +static uint8_t * mp_tx_buffer; /**< Pointer to TX application buffer to be transmitted. */ +static uint32_t m_tx_buffer_length; /**< Length of application TX packet data to be transmitted in bytes. */ +static bool m_is_slip_decode_ready; /**< Boolean to determine has slip decode been completed or not. */ +APP_TIMER_DEF(m_app_timer_id); /**< Application timer id. */ +static uint32_t m_tx_retry_counter; /**< Application packet retransmission counter. */ +static hci_transport_tx_done_result_t m_tx_done_result_code; /**< TX done event callback function result code. */ +static uint8_t m_rx_ack_buffer[ACK_BUF_SIZE];/**< RX buffer big enough to hold an acknowledgement packet and which is taken in use upon receiving HCI_SLIP_RX_OVERFLOW event. */ + + +/**@brief Function for validating a received packet. + * + * @param[in] p_buffer Pointer to the packet data. + * @param[in] length Length of packet data in bytes. + * + * @return true if received packet is valid, false in other case. + */ +static bool is_rx_pkt_valid(const uint8_t * p_buffer, uint32_t length) +{ + // Executed packet filtering algorithm order: + // - verify packet overall length + // - verify data integrity bit set + // - verify reliable packet bit set + // - verify supported packet type + // - verify header checksum + // - verify payload length field + // - verify CRC + if (length <= PKT_HDR_SIZE) + { + return false; + } + + if (!(p_buffer[0] & DATA_INTEGRITY_MASK)) + { + return false; + } + + if (!(p_buffer[0] & RELIABLE_PKT_MASK)) + { + return false; + } + + if ((p_buffer[1] & 0x0Fu) != PKT_TYPE_VENDOR_SPECIFIC) + { + return false; + } + + const uint32_t expected_checksum = + ((p_buffer[0] + p_buffer[1] + p_buffer[2] + p_buffer[3])) & 0xFFu; + if (expected_checksum != 0) + { + return false; + } + + const uint16_t crc_calculated = crc16_compute(p_buffer, (length - PKT_CRC_SIZE), NULL); + const uint16_t crc_received = uint16_decode(&p_buffer[length - PKT_CRC_SIZE]); + if (crc_calculated != crc_received) + { + return false; + } + + return true; +} + + +/**@brief Function for getting the sequence number of the next reliable packet expected. + * + * @return sequence number of the next reliable packet expected. + */ +static __INLINE uint8_t packet_number_expected_get(void) +{ + return (uint8_t) m_packet_expected_seq_number; +} + + +/**@brief Function for calculating a packet header checksum. + * + * @param[in] p_hdr Pointer to the packet header. + * + * @return Calculated checksum. + */ +static uint8_t header_checksum_calculate(const uint8_t * p_hdr) +{ + // @note: no pointer validation check needed as already checked by calling function. + uint32_t checksum; + + checksum = p_hdr[0]; + checksum += p_hdr[1]; + checksum += p_hdr[2]; + checksum &= 0xFFu; + checksum = (~checksum + 1u); + + return (uint8_t)checksum; +} + + +/**@brief Function for writing an acknowledgment packet for transmission. + */ +static void ack_transmit(void) +{ + static uint8_t ack_packet[PKT_HDR_SIZE]; + + // TX ACK packet format: + // - Unreliable Packet type + // - Payload Length set to 0 + // - Sequence Number set to 0 + // - Header checksum calculated + // - Acknowledge Number set correctly + ack_packet[0] = (packet_number_expected_get() << 3u); + ack_packet[1] = 0; + ack_packet[2] = 0; + ack_packet[3] = header_checksum_calculate(ack_packet); + + // @note: no return value check needed for hci_slip_write(...) call as acknowledgement packets + // are considered to be from system design point of view unreliable packets.Use case where + // underlying slip layer does not accept a packet for transmission is managed either by: + // - acknowledged by possible future application packet as acknowledgement number header field + // is included + // - protocol peer entity will retransmit the packet + UNUSED_VARIABLE(hci_slip_write(ack_packet, sizeof(ack_packet))); +} + + +/**@brief Function for validating a received packet. + * + * @param[in] p_buffer Pointer to the packet data. + * + * @return sequence number field of the packet header with unrelated data masked out. + */ +static __INLINE uint8_t packet_seq_nmbr_extract(const uint8_t * p_buffer) +{ + return (p_buffer[0] & 0x07u); +} + + +/**@brief Function for incrementing the sequence number counter for next reliable packet expected. + */ +static __INLINE void packet_number_expected_inc(void) +{ + ++m_packet_expected_seq_number; + m_packet_expected_seq_number &= 0x07u; +} + + +/**@brief Function for decoding a packet type field. + * + * @param[in] p_buffer Pointer to the packet data. + * @param[in] length Length of packet data in bytes. + * + * @return Packet type field or INVALID_PKT_TYPE in case of decode error. + */ +static __INLINE uint32_t packet_type_decode(const uint8_t * p_buffer, uint32_t length) +{ + // @note: no pointer validation check needed as allready checked by calling function. + uint32_t return_value; + + if (length >= PKT_HDR_SIZE) + { + return_value = (p_buffer[1] & 0x0Fu); + } + else + { + return_value = INVALID_PKT_TYPE; + } + + return return_value; +} + + +/**@brief Function for processing a received vendor specific packet. + * + * @param[in] p_buffer Pointer to the packet data. + * @param[in] length Length of packet data in bytes. + */ +static void rx_vendor_specific_pkt_type_handle(const uint8_t * p_buffer, uint32_t length) +{ + // @note: no pointer validation check needed as allready checked by calling function. + uint32_t err_code; + + if (is_rx_pkt_valid(p_buffer, length)) + { + // RX packet is valid: validate sequence number. + const uint8_t rx_seq_number = packet_seq_nmbr_extract(p_buffer); + if (packet_number_expected_get() == rx_seq_number) + { + // Sequence number is valid: transmit acknowledgement. + packet_number_expected_inc(); + ack_transmit(); + + m_is_slip_decode_ready = true; + + err_code = hci_mem_pool_rx_data_size_set(length); + APP_ERROR_CHECK(err_code); + + err_code = hci_mem_pool_rx_produce(HCI_RX_BUF_SIZE, (void **)&mp_slip_used_rx_buffer); + APP_ERROR_CHECK_BOOL((err_code == NRF_SUCCESS) || (err_code == NRF_ERROR_NO_MEM)); + + // If memory pool RX buffer produce succeeded we register that buffer to slip layer + // otherwise we register the internal acknowledgement buffer. + err_code = hci_slip_rx_buffer_register( + (err_code == NRF_SUCCESS) ? mp_slip_used_rx_buffer : m_rx_ack_buffer, + (err_code == NRF_SUCCESS) ? HCI_RX_BUF_SIZE : ACK_BUF_SIZE); + + APP_ERROR_CHECK(err_code); + + if (m_transport_event_handle != NULL) + { + // Send application event of RX packet reception. + const hci_transport_evt_t evt = {HCI_TRANSPORT_RX_RDY}; + m_transport_event_handle(evt); + } + } + else + { + // RX packet discarded: sequence number not valid, set the same buffer to slip layer in + // order to avoid buffer overrun. + err_code = hci_slip_rx_buffer_register(mp_slip_used_rx_buffer, HCI_RX_BUF_SIZE); + APP_ERROR_CHECK(err_code); + + // As packet did not have expected sequence number: send acknowledgement with the + // current expected sequence number. + ack_transmit(); + } + } + else + { + // RX packet discarded: reset the same buffer to slip layer in order to avoid buffer + // overrun. + err_code = hci_slip_rx_buffer_register(mp_slip_used_rx_buffer, HCI_RX_BUF_SIZE); + APP_ERROR_CHECK(err_code); + } +} + + +/**@brief Function for getting the sequence number of a reliable TX packet for which peer protocol + * entity acknowledgment is pending. + * + * @return sequence number of a reliable TX packet for which peer protocol entity acknowledgement + * is pending. + */ +static __INLINE uint8_t packet_number_to_transmit_get(void) +{ + return m_packet_transmit_seq_number; +} + + +/**@brief Function for getting the expected acknowledgement number. + * + * @return expected acknowledgement number. + */ +static __INLINE uint8_t expected_ack_number_get(void) +{ + uint8_t seq_nmbr = packet_number_to_transmit_get(); + ++seq_nmbr; + seq_nmbr &= 0x07u; + + return seq_nmbr; +} + + +/**@brief Function for processing a received acknowledgement packet. + * + * Verifies does the received acknowledgement packet has the expected acknowledgement number and + * that the header checksum is correct. + * + * @param[in] p_buffer Pointer to the packet data. + * + * @return true if valid acknowledgement packet received. + */ +static __INLINE bool rx_ack_pkt_type_handle(const uint8_t * p_buffer) +{ + // @note: no pointer validation check needed as allready checked by calling function. + + // Verify header checksum. + const uint32_t expected_checksum = + ((p_buffer[0] + p_buffer[1] + p_buffer[2] + p_buffer[3])) & 0xFFu; + if (expected_checksum != 0) + { + return false; + } + + const uint8_t ack_number = (p_buffer[0] >> 3u) & 0x07u; + + // Verify expected acknowledgment number. + return (ack_number == expected_ack_number_get()); +} + + +/**@brief Function for incrementing the sequence number counter of the TX packet. + */ +static __INLINE void packet_number_tx_inc(void) +{ + ++m_packet_transmit_seq_number; + m_packet_transmit_seq_number &= 0x07u; +} + + +/**@brief Function for TX state machine event processing in a state centric manner. + * + * @param[in] event Type of event occurred. + */ +static void tx_sm_event_handle(tx_event_t event) +{ + uint32_t err_code; + + switch (m_tx_state) + { + case TX_STATE_IDLE: + if (event == TX_EVENT_STATE_ENTRY) + { + err_code = app_timer_stop(m_app_timer_id); + APP_ERROR_CHECK(err_code); + + // Send TX-done event if registered handler exists. + if (m_transport_tx_done_handle != NULL) + { + m_transport_tx_done_handle(m_tx_done_result_code); + } + } + break; + + case TX_STATE_PENDING: + if (event == TX_EVENT_SLIP_TX_DONE) + { + // @note: this call should always succeed as called from HCI_SLIP_TX_DONE context + // and error cases are managed by dedicated error event from the slip layer. + err_code = hci_slip_write(mp_tx_buffer, + (m_tx_buffer_length + PKT_HDR_SIZE + PKT_CRC_SIZE)); + APP_ERROR_CHECK(err_code); + tx_sm_state_change(TX_STATE_ACTIVE); + } + break; + + case TX_STATE_ACTIVE: + switch (event) + { + case TX_EVENT_VALID_RX_ACK: + // Tx sequence number counter incremented as packet transmission + // acknowledged by peer transport entity. + packet_number_tx_inc(); + tx_sm_state_change(TX_STATE_IDLE); + break; + + case TX_EVENT_STATE_ENTRY: + m_tx_retry_counter = 0; + err_code = app_timer_start(m_app_timer_id, + RETRANSMISSION_TIMEOUT_IN_TICKS, + NULL); + APP_ERROR_CHECK(err_code); + break; + + case TX_EVENT_TIMEOUT: + if (m_tx_retry_counter != MAX_RETRY_COUNT) + { + ++m_tx_retry_counter; + // @note: no return value check done for hci_slip_write(...) call as current + // system design allows use case where retransmission is not accepted by the + // slip layer due to existing acknowledgement packet transmission in the + // slip layer. + UNUSED_VARIABLE(hci_slip_write(mp_tx_buffer, + (m_tx_buffer_length + + PKT_HDR_SIZE + + PKT_CRC_SIZE))); + } + else + { + // Application packet retransmission count reached: + // - set correct TX done event callback function result code + // - execute state change + // @note: m_tx_retry_counter is reset in TX_STATE_ACTIVE state entry. + m_tx_done_result_code = HCI_TRANSPORT_TX_DONE_FAILURE; + tx_sm_state_change(TX_STATE_IDLE); + } + break; + + default: + // No implementation needed. + break; + } + break; + + default: + // No implementation needed. + break; + } +} + + +/**@brief Function for changing the state of the TX state machine. + * + * @param[in] new_state State TX state machine transits to. + */ +static void tx_sm_state_change(tx_state_t new_state) +{ + m_tx_state = new_state; + tx_sm_event_handle(TX_EVENT_STATE_ENTRY); +} + + +/**@brief Function for handling slip events. + * + * @param[in] event The event structure. + */ +void slip_event_handle(hci_slip_evt_t event) +{ + uint32_t return_code; + uint32_t err_code; + + switch (event.evt_type) + { + case HCI_SLIP_TX_DONE: + tx_sm_event_handle(TX_EVENT_SLIP_TX_DONE); + break; + + case HCI_SLIP_RX_RDY: + return_code = packet_type_decode(event.packet, event.packet_length); + + switch (return_code) + { + case PKT_TYPE_VENDOR_SPECIFIC: + rx_vendor_specific_pkt_type_handle(event.packet, event.packet_length); + break; + + case PKT_TYPE_ACK: + if (rx_ack_pkt_type_handle(event.packet)) + { + // Valid expected acknowledgement packet received: set correct TX done event + // callback function result code and execute state change. + m_tx_done_result_code = HCI_TRANSPORT_TX_DONE_SUCCESS; + tx_sm_event_handle(TX_EVENT_VALID_RX_ACK); + } + + /* fall-through */ + default: + // RX packet dropped: reset memory buffer to slip in order to avoid RX buffer + // overflow. + // If existing mem pool produced RX buffer exists reuse that one. If existing + // mem pool produced RX buffer does not exist try to produce new one. If + // producing fails use the internal acknowledgement buffer. + if (mp_slip_used_rx_buffer != NULL) + { + err_code = hci_slip_rx_buffer_register(mp_slip_used_rx_buffer, HCI_RX_BUF_SIZE); + APP_ERROR_CHECK(err_code); + } + else + { + err_code = hci_mem_pool_rx_produce(HCI_RX_BUF_SIZE, + (void **)&mp_slip_used_rx_buffer); + APP_ERROR_CHECK_BOOL((err_code == NRF_SUCCESS) || + (err_code == NRF_ERROR_NO_MEM)); + + err_code = hci_slip_rx_buffer_register( + (err_code == NRF_SUCCESS) ? mp_slip_used_rx_buffer : m_rx_ack_buffer, + (err_code == NRF_SUCCESS) ? HCI_RX_BUF_SIZE : ACK_BUF_SIZE); + APP_ERROR_CHECK(err_code); + } + break; + } + break; + + case HCI_SLIP_RX_OVERFLOW: + err_code = hci_slip_rx_buffer_register(m_rx_ack_buffer, ACK_BUF_SIZE); + APP_ERROR_CHECK(err_code); + break; + + case HCI_SLIP_ERROR: + APP_ERROR_HANDLER(event.evt_type); + break; + + default: + APP_ERROR_HANDLER(event.evt_type); + break; + } +} + + +uint32_t hci_transport_evt_handler_reg(hci_transport_event_handler_t event_handler) +{ + uint32_t err_code; + + m_transport_event_handle = event_handler; + err_code = hci_slip_evt_handler_register(slip_event_handle); + APP_ERROR_CHECK(err_code); + + return (event_handler != NULL) ? NRF_SUCCESS : NRF_ERROR_NULL; +} + + +uint32_t hci_transport_tx_done_register(hci_transport_tx_done_handler_t event_handler) +{ + uint32_t err_code; + + m_transport_tx_done_handle = event_handler; + err_code = hci_slip_evt_handler_register(slip_event_handle); + APP_ERROR_CHECK(err_code); + + return (event_handler != NULL) ? NRF_SUCCESS : NRF_ERROR_NULL; +} + + +/**@brief Function for handling the application packet retransmission timeout. + * + * This function is registered in the @ref app_timer module when a timer is created on + * @ref hci_transport_open. + * + * @note This function must be executed in APP-LO context otherwise retransmission behaviour is + * undefined, see @ref nrf51_system_integration_serialization. + * + * @param[in] p_context The timeout context. + */ +void hci_transport_timeout_handle(void * p_context) +{ + tx_sm_event_handle(TX_EVENT_TIMEOUT); +} + + +uint32_t hci_transport_open(void) +{ + mp_tx_buffer = NULL; + m_tx_buffer_length = 0; + m_tx_retry_counter = 0; + m_is_slip_decode_ready = false; + m_tx_state = TX_STATE_IDLE; + m_packet_expected_seq_number = INITIAL_ACK_NUMBER_EXPECTED; + m_packet_transmit_seq_number = INITIAL_ACK_NUMBER_TX; + m_tx_done_result_code = HCI_TRANSPORT_TX_DONE_FAILURE; + + uint32_t err_code = app_timer_create(&m_app_timer_id, + APP_TIMER_MODE_REPEATED, + hci_transport_timeout_handle); + if (err_code != NRF_SUCCESS) + { + // @note: conduct required interface adjustment. + return NRF_ERROR_INTERNAL; + } + + err_code = hci_mem_pool_open(); + VERIFY_SUCCESS(err_code); + + err_code = hci_slip_open(); + VERIFY_SUCCESS(err_code); + + err_code = hci_mem_pool_rx_produce(HCI_RX_BUF_SIZE, (void **)&mp_slip_used_rx_buffer); + if (err_code != NRF_SUCCESS) + { + // @note: conduct required interface adjustment. + return NRF_ERROR_INTERNAL; + } + + err_code = hci_slip_rx_buffer_register(mp_slip_used_rx_buffer, HCI_RX_BUF_SIZE); + + return err_code; +} + + +uint32_t hci_transport_close(void) +{ + uint32_t err_code; + + m_transport_tx_done_handle = NULL; + m_transport_event_handle = NULL; + + err_code = hci_mem_pool_close(); + APP_ERROR_CHECK(err_code); + err_code = hci_slip_close(); + APP_ERROR_CHECK(err_code); + + // @note: NRF_ERROR_NO_MEM is the only return value which should never be returned. + err_code = app_timer_stop(m_app_timer_id); + APP_ERROR_CHECK_BOOL(err_code != NRF_ERROR_NO_MEM); + + return NRF_SUCCESS; +} + + +uint32_t hci_transport_tx_alloc(uint8_t ** pp_memory) +{ + const uint32_t err_code = hci_mem_pool_tx_alloc((void **)pp_memory); + if (err_code == NRF_SUCCESS) + { + // @note: no need to validate pp_memory against null as validation has already been done + // by hci_mem_pool_tx_alloc(...) and visible to us from the method return code. + //lint -e(413) "Likely use of null pointer" + *pp_memory += PKT_HDR_SIZE; + } + + return err_code; +} + + +uint32_t hci_transport_tx_free(void) +{ + return hci_mem_pool_tx_free(); +} + + +/**@brief Function for constructing 1st byte of the packet header of the packet to be transmitted. + * + * @return 1st byte of the packet header of the packet to be transmitted + */ +static __INLINE uint8_t tx_packet_byte_zero_construct(void) +{ + const uint32_t value = DATA_INTEGRITY_MASK | + RELIABLE_PKT_MASK | + (packet_number_expected_get() << 3u) | + packet_number_to_transmit_get(); + + return (uint8_t) value; +} + + +/**@brief Function for handling the application packet write request in tx-idle state. + */ +static uint32_t pkt_write_handle(void) +{ + uint32_t err_code; + + // Set packet header fields. + + mp_tx_buffer -= PKT_HDR_SIZE; + mp_tx_buffer[0] = tx_packet_byte_zero_construct(); + + const uint16_t type_and_length_fields = ((m_tx_buffer_length << 4u) | PKT_TYPE_VENDOR_SPECIFIC); + // @note: no use case for uint16_encode(...) return value. + UNUSED_VARIABLE(uint16_encode(type_and_length_fields, &(mp_tx_buffer[1]))); + mp_tx_buffer[3] = header_checksum_calculate(mp_tx_buffer); + + // Calculate, append CRC to the packet and write it. + + const uint16_t crc = crc16_compute(mp_tx_buffer, (PKT_HDR_SIZE + m_tx_buffer_length), NULL); + // @note: no use case for uint16_encode(...) return value. + UNUSED_VARIABLE(uint16_encode(crc, &(mp_tx_buffer[PKT_HDR_SIZE + m_tx_buffer_length]))); + err_code = hci_slip_write(mp_tx_buffer, (m_tx_buffer_length + PKT_HDR_SIZE + PKT_CRC_SIZE)); + switch (err_code) + { + case NRF_SUCCESS: + tx_sm_state_change(TX_STATE_ACTIVE); + break; + + case NRF_ERROR_NO_MEM: + tx_sm_state_change(TX_STATE_PENDING); + err_code = NRF_SUCCESS; + break; + + default: + // No implementation needed. + break; + } + + return err_code; +} + + +uint32_t hci_transport_pkt_write(const uint8_t * p_buffer, uint16_t length) +{ + uint32_t err_code; + + if (p_buffer) + { + switch (m_tx_state) + { + case TX_STATE_IDLE: + mp_tx_buffer = (uint8_t *)p_buffer; + m_tx_buffer_length = length; + err_code = pkt_write_handle(); + break; + + default: + err_code = NRF_ERROR_NO_MEM; + break; + } + } + else + { + err_code = NRF_ERROR_NULL; + } + + return err_code; +} + + +uint32_t hci_transport_rx_pkt_extract(uint8_t ** pp_buffer, uint16_t * p_length) +{ + uint32_t err_code; + + if (pp_buffer != NULL && p_length != NULL) + { + uint32_t length = 0; + + if (m_is_slip_decode_ready) + { + m_is_slip_decode_ready = false; + err_code = hci_mem_pool_rx_extract(pp_buffer, &length); + length -= (PKT_HDR_SIZE + PKT_CRC_SIZE); + + *p_length = (uint16_t)length; + *pp_buffer += PKT_HDR_SIZE; + } + else + { + err_code = NRF_ERROR_NO_MEM; + } + } + else + { + err_code = NRF_ERROR_NULL; + } + + return err_code; +} + + +uint32_t hci_transport_rx_pkt_consume(uint8_t * p_buffer) +{ + return (hci_mem_pool_rx_consume(p_buffer - PKT_HDR_SIZE)); +} +#endif //NRF_MODULE_ENABLED(HCI_TRANSPORT) |