Swati Wagh | 9be741a | 2021-11-19 19:49:28 +0000 | [diff] [blame] | 1 | // Copyright 2022 The Pigweed Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| 4 | // use this file except in compliance with the License. You may obtain a copy of |
| 5 | // the License at |
| 6 | // |
| 7 | // https://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| 11 | // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| 12 | // License for the specific language governing permissions and limitations under |
| 13 | // the License. |
| 14 | #include "pw_i2c_mcuxpresso/initiator.h" |
| 15 | |
| 16 | #include <mutex> |
| 17 | |
| 18 | #include "fsl_i2c.h" |
| 19 | #include "pw_chrono/system_clock.h" |
| 20 | #include "pw_status/status.h" |
| 21 | #include "pw_status/try.h" |
| 22 | |
| 23 | namespace pw::i2c { |
| 24 | namespace { |
| 25 | |
| 26 | Status HalStatusToPwStatus(status_t status) { |
| 27 | switch (status) { |
| 28 | case kStatus_Success: |
| 29 | return OkStatus(); |
| 30 | case kStatus_I2C_Nak: |
| 31 | case kStatus_I2C_Addr_Nak: |
| 32 | return Status::Unavailable(); |
| 33 | case kStatus_I2C_InvalidParameter: |
| 34 | return Status::InvalidArgument(); |
| 35 | case kStatus_I2C_Timeout: |
| 36 | return Status::DeadlineExceeded(); |
| 37 | default: |
| 38 | return Status::Unknown(); |
| 39 | } |
| 40 | } |
| 41 | } // namespace |
| 42 | |
| 43 | // inclusive-language: disable |
| 44 | McuxpressoInitiator::McuxpressoInitiator(I2C_Type* base, |
| 45 | uint32_t baud_rate_bps, |
| 46 | uint32_t src_clock_hz) |
| 47 | : base_(base) { |
| 48 | i2c_master_config_t master_config; |
| 49 | I2C_MasterGetDefaultConfig(&master_config); |
| 50 | master_config.baudRate_Bps = baud_rate_bps; |
| 51 | I2C_MasterInit(base_, &master_config, src_clock_hz); |
| 52 | |
| 53 | // Create the handle for the non-blocking transfer and register callback. |
| 54 | I2C_MasterTransferCreateHandle( |
| 55 | base_, &handle_, McuxpressoInitiator::TransferCompleteCallback, this); |
| 56 | } |
| 57 | |
| 58 | McuxpressoInitiator::~McuxpressoInitiator() { I2C_MasterDeinit(base_); } |
| 59 | |
| 60 | void McuxpressoInitiator::TransferCompleteCallback(I2C_Type* base, |
| 61 | i2c_master_handle_t* handle, |
| 62 | status_t status, |
| 63 | void* initiator_ptr) { |
| 64 | McuxpressoInitiator& initiator = |
| 65 | *static_cast<McuxpressoInitiator*>(initiator_ptr); |
| 66 | initiator.callback_isl_.lock(); |
| 67 | initiator.transfer_status_ = status; |
| 68 | initiator.callback_isl_.unlock(); |
| 69 | initiator.callback_complete_notification_.release(); |
| 70 | } |
| 71 | |
| 72 | Status McuxpressoInitiator::InitiateNonBlockingTransfer( |
| 73 | chrono::SystemClock::duration rw_timeout, i2c_master_transfer_t* transfer) { |
| 74 | const status_t status = |
| 75 | I2C_MasterTransferNonBlocking(base_, &handle_, transfer); |
| 76 | if (status != kStatus_Success) { |
| 77 | return HalStatusToPwStatus(status); |
| 78 | } |
| 79 | |
| 80 | if (!callback_complete_notification_.try_acquire_for(rw_timeout)) { |
| 81 | I2C_MasterTransferAbort(base_, &handle_); |
| 82 | return Status::DeadlineExceeded(); |
| 83 | } |
| 84 | |
| 85 | callback_isl_.lock(); |
| 86 | const status_t transfer_status = transfer_status_; |
| 87 | callback_isl_.unlock(); |
| 88 | |
| 89 | return HalStatusToPwStatus(transfer_status); |
| 90 | } |
| 91 | |
| 92 | // Performs non-blocking I2C write, read and read-after-write depending on the |
| 93 | // tx and rx buffer states. |
| 94 | Status McuxpressoInitiator::DoWriteReadFor( |
| 95 | Address device_address, |
| 96 | ConstByteSpan tx_buffer, |
| 97 | ByteSpan rx_buffer, |
| 98 | chrono::SystemClock::duration timeout) { |
| 99 | if (timeout <= chrono::SystemClock::duration::zero()) { |
| 100 | return Status::DeadlineExceeded(); |
| 101 | } |
| 102 | |
| 103 | const uint8_t address = device_address.GetSevenBit(); |
| 104 | std::lock_guard lock(mutex_); |
| 105 | |
| 106 | if (!tx_buffer.empty() && rx_buffer.empty()) { |
| 107 | i2c_master_transfer_t transfer{kI2C_TransferDefaultFlag, |
| 108 | address, |
| 109 | kI2C_Write, |
| 110 | 0, |
| 111 | 0, |
| 112 | const_cast<std::byte*>(tx_buffer.data()), |
| 113 | tx_buffer.size()}; |
| 114 | return InitiateNonBlockingTransfer(timeout, &transfer); |
| 115 | } else if (tx_buffer.empty() && !rx_buffer.empty()) { |
| 116 | i2c_master_transfer_t transfer{kI2C_TransferDefaultFlag, |
| 117 | address, |
| 118 | kI2C_Read, |
| 119 | 0, |
| 120 | 0, |
| 121 | rx_buffer.data(), |
| 122 | rx_buffer.size()}; |
| 123 | return InitiateNonBlockingTransfer(timeout, &transfer); |
| 124 | } else if (!tx_buffer.empty() && !rx_buffer.empty()) { |
| 125 | i2c_master_transfer_t w_transfer{kI2C_TransferNoStopFlag, |
| 126 | address, |
| 127 | kI2C_Write, |
| 128 | 0, |
| 129 | 0, |
| 130 | const_cast<std::byte*>(tx_buffer.data()), |
| 131 | tx_buffer.size()}; |
| 132 | const chrono::SystemClock::time_point deadline = |
| 133 | chrono::SystemClock::TimePointAfterAtLeast(timeout); |
| 134 | PW_TRY(InitiateNonBlockingTransfer(timeout, &w_transfer)); |
| 135 | i2c_master_transfer_t r_transfer{kI2C_TransferRepeatedStartFlag, |
| 136 | address, |
| 137 | kI2C_Read, |
| 138 | 0, |
| 139 | 0, |
| 140 | rx_buffer.data(), |
| 141 | rx_buffer.size()}; |
| 142 | const chrono::SystemClock::duration time_remaining = |
| 143 | deadline - chrono::SystemClock::now(); |
| 144 | if (time_remaining <= chrono::SystemClock::duration::zero()) { |
| 145 | // Abort transfer in an unlikely scenario of timeout even with |
| 146 | // successful write. |
| 147 | I2C_MasterTransferAbort(base_, &handle_); |
| 148 | return Status::DeadlineExceeded(); |
| 149 | } |
| 150 | return InitiateNonBlockingTransfer(time_remaining, &r_transfer); |
| 151 | } else { |
| 152 | return Status::InvalidArgument(); |
| 153 | } |
| 154 | } |
| 155 | // inclusive-language: enable |
| 156 | } // namespace pw::i2c |