Line data    Source code

       1            1 : /*
       2              :  * Copyright 2020 Google LLC
       3              :  *
       4              :  * SPDX-License-Identifier: Apache-2.0
       5              :  */
       6              : 
       7              : #ifndef ZEPHYR_INCLUDE_DRIVERS_SPI_SPI_EMUL_H_
       8              : #define ZEPHYR_INCLUDE_DRIVERS_SPI_SPI_EMUL_H_
       9              : 
      10              : #include <zephyr/device.h>
      11              : #include <zephyr/drivers/emul.h>
      12              : #include <zephyr/drivers/spi.h>
      13              : #include <zephyr/sys/slist.h>
      14              : #include <zephyr/types.h>
      15              : 
      16              : /**
      17              :  * @file
      18              :  *
      19              :  * @brief Public APIs for the SPI emulation drivers.
      20              :  */
      21              : 
      22              : /**
      23              :  * @brief SPI Emulation Interface
      24              :  * @defgroup spi_emul_interface SPI Emulation Interface
      25              :  * @ingroup io_emulators
      26              :  * @ingroup spi_interface
      27              :  * @{
      28              :  */
      29              : 
      30              : #ifdef __cplusplus
      31              : extern "C" {
      32              : #endif
      33              : 
      34              : struct spi_msg;
      35              : struct spi_emul_api;
      36              : 
      37              : /** Node in a linked list of emulators for SPI devices */
      38            1 : struct spi_emul {
      39            0 :         sys_snode_t node;
      40              : 
      41              :         /** Target emulator - REQUIRED for all bus emulators */
      42            1 :         const struct emul *target;
      43              : 
      44              :         /* API provided for this device */
      45            0 :         const struct spi_emul_api *api;
      46              : 
      47              :         /**
      48              :          * A mock API that if not NULL will take precedence over the actual API. If set, a return
      49              :          * value of -ENOSYS will revert back to the default api.
      50              :          */
      51            1 :         struct spi_emul_api *mock_api;
      52              : 
      53              :         /* SPI chip-select of the emulated device */
      54            0 :         uint16_t chipsel;
      55              : };
      56              : 
      57              : /**
      58              :  * Passes SPI messages to the emulator. The emulator updates the data with what
      59              :  * was read back.
      60              :  *
      61              :  * @param target The device Emulator instance
      62              :  * @param config Pointer to a valid spi_config structure instance.
      63              :  *        Pointer-comparison may be used to detect changes from
      64              :  *        previous operations.
      65              :  * @param tx_bufs Buffer array where data to be sent originates from,
      66              :  *        or NULL if none.
      67              :  * @param rx_bufs Buffer array where data to be read will be written to,
      68              :  *        or NULL if none.
      69              :  *
      70              :  * @retval 0 If successful.
      71              :  * @retval -EIO General input / output error.
      72              :  */
      73            1 : typedef int (*spi_emul_io_t)(const struct emul *target, const struct spi_config *config,
      74              :                              const struct spi_buf_set *tx_bufs, const struct spi_buf_set *rx_bufs);
      75              : 
      76              : /**
      77              :  * Register an emulated device on the controller
      78              :  *
      79              :  * @param dev Device that will use the emulator
      80              :  * @param emul SPI emulator to use
      81              :  * @return 0 indicating success (always)
      82              :  */
      83            1 : int spi_emul_register(const struct device *dev, struct spi_emul *emul);
      84              : 
      85              : /** Definition of the emulator API */
      86            1 : struct spi_emul_api {
      87            0 :         spi_emul_io_t io;
      88              : };
      89              : 
      90              : /**
      91              :  * Back door to allow an emulator to retrieve the host configuration.
      92              :  *
      93              :  * @param dev SPI device associated with the emulator
      94              :  * @return Bit-packed 32-bit value containing the device's runtime configuration
      95              :  */
      96            1 : uint32_t spi_emul_get_config(const struct device *dev);
      97              : 
      98              : #ifdef __cplusplus
      99              : }
     100              : #endif
     101              : 
     102              : /**
     103              :  * @}
     104              :  */
     105              : 
     106              : #endif /* ZEPHYR_INCLUDE_DRIVERS_SPI_SPI_EMUL_H_ */