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