1 // Copyright 2021 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 15 #pragma once 16 17 #include <cstdint> 18 #include <optional> 19 20 #include "pw_bytes/span.h" 21 #include "pw_spi/chip_selector.h" 22 #include "pw_spi/initiator.h" 23 #include "pw_status/status.h" 24 25 namespace pw::spi { 26 27 // Linux userspace implementation of the SPI Initiator 28 class LinuxInitiator : public Initiator { 29 public: 30 // Configure the Linux Initiator object for use with a bus file descriptor, 31 // and maximum bus-speed (in hz). LinuxInitiator(int fd,uint32_t max_speed_hz)32 constexpr LinuxInitiator(int fd, uint32_t max_speed_hz) 33 : max_speed_hz_(max_speed_hz), fd_(fd) {} 34 ~LinuxInitiator() override; 35 36 private: 37 uint32_t max_speed_hz_; 38 int fd_; 39 std::optional<Config> current_config_; 40 41 // Implements pw::spi::Initiator 42 Status DoConfigure(const Config& config) override; 43 Status DoWriteRead(ConstByteSpan write_buffer, ByteSpan read_buffer) override; 44 }; 45 46 // Linux userspace implementation of SPI ChipSelector 47 class LinuxChipSelector : public ChipSelector { 48 public: 49 Status SetActive(bool active) override; 50 }; 51 52 } // namespace pw::spi 53