| /* |
| * Copyright (C) 2016 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef SYSTEM_PERIPHERALMANAGER_SPI_DEVICE_H_ |
| #define SYSTEM_PERIPHERALMANAGER_SPI_DEVICE_H_ |
| |
| #include <sys/cdefs.h> |
| #include <sys/types.h> |
| |
| __BEGIN_DECLS |
| |
| /// @defgroup Spi Spi device interface |
| /// @brief Functions to control an SPI device. |
| /// |
| /// These functions can be used to control an SPI device. |
| /// @{ |
| |
| /// Endianness. |
| enum { |
| SPI_LSB_FIRST, /**< Least significant bits first */ |
| SPI_MSB_FIRST /**< Most significant bits first */ |
| }; |
| |
| /// SPI phase modes. |
| enum { |
| SPI_CPHA = 0x01, /**< Clock phase */ |
| SPI_CPOL = 0x02 /**< Clock polarity */ |
| }; |
| |
| /// SPI modes (similar to the Linux kernel's modes). |
| enum { |
| SPI_MODE0 = 0, /**< CPHA=0, CPOL=0 */ |
| SPI_MODE1 = SPI_CPHA, /**< CPHA=1, CPOL=0 */ |
| SPI_MODE2 = SPI_CPOL, /**< CPHA=0, CPOL=1 */ |
| SPI_MODE3 = SPI_CPHA + SPI_CPOL /**< CPHA=1, CPOL=1 */ |
| }; |
| |
| typedef struct BSpiDevice BSpiDevice; |
| |
| /// Writes a byte to the device. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param val Value to write. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_writeByte(const BSpiDevice* device, uint8_t val); |
| |
| /// Writes a buffer to the device. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param data Buffer to write. |
| /// @param len Length of the buffer. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_writeBuffer(const BSpiDevice* device, |
| const void* data, |
| size_t len); |
| |
| /// Transfer data to the device. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param tx_data Buffer to write. |
| /// @param rx_data Buffer to read data in. If NULL, no data will be read. |
| /// @param len Length of the buffers. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_transfer(const BSpiDevice* device, |
| const void* tx_data, |
| void* rx_data, |
| size_t len); |
| |
| /// Sets the frequency in Hertz. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param freq_hz Frequency to set. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_setFrequency(const BSpiDevice* device, uint32_t freq_hz); |
| |
| /// Sets the SPI mode. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param mode Mode to use. One of SPI_MODE0, SPI_MODE1, SPI_MODE2, SPI_MODE3. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_setMode(const BSpiDevice* device, int mode); |
| |
| /// Sets the bit justification. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param bit_justification One of SPI_LSB_FIRST OR SPI_MSB_FIRST. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_setBitJustification(const BSpiDevice* device, |
| int bit_justification); |
| |
| /// Sets the number of bits per words. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param bits_per_word Number of bits per word. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_setBitsPerWord(const BSpiDevice* device, uint8_t bits_per_word); |
| |
| /// Sets the delay to wait after each transfer. |
| /// @param device Pointer to the BSpiDevice struct. |
| /// @param delay_usecs Delay in microseconds. |
| /// @return 0 on success, errno on error. |
| int BSpiDevice_setDelay(const BSpiDevice* device, uint16_t delay_usecs); |
| |
| /// Destroys a BSpiDevice struct. |
| /// @param device Pointer to the BSpiDevice struct. |
| void BSpiDevice_delete(BSpiDevice* device); |
| |
| /// @} |
| |
| __END_DECLS |
| |
| #endif // SYSTEM_PERIPHERALMANAGER_SPI_DEVICE_H_ |