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             :  * @{
      27             :  */
      28             : 
      29             : #ifdef __cplusplus
      30             : extern "C" {
      31             : #endif
      32             : 
      33             : struct spi_msg;
      34             : struct spi_emul_api;
      35             : 
      36             : /** Node in a linked list of emulators for SPI devices */
      37           1 : struct spi_emul {
      38           0 :         sys_snode_t node;
      39             : 
      40             :         /** Target emulator - REQUIRED for all bus emulators */
      41           1 :         const struct emul *target;
      42             : 
      43             :         /* API provided for this device */
      44           0 :         const struct spi_emul_api *api;
      45             : 
      46             :         /**
      47             :          * A mock API that if not NULL will take precedence over the actual API. If set, a return
      48             :          * value of -ENOSYS will revert back to the default api.
      49             :          */
      50           1 :         struct spi_emul_api *mock_api;
      51             : 
      52             :         /* SPI chip-select of the emulated device */
      53           0 :         uint16_t chipsel;
      54             : };
      55             : 
      56             : /**
      57             :  * Passes SPI messages to the emulator. The emulator updates the data with what
      58             :  * was read back.
      59             :  *
      60             :  * @param target The device Emulator instance
      61             :  * @param config Pointer to a valid spi_config structure instance.
      62             :  *        Pointer-comparison may be used to detect changes from
      63             :  *        previous operations.
      64             :  * @param tx_bufs Buffer array where data to be sent originates from,
      65             :  *        or NULL if none.
      66             :  * @param rx_bufs Buffer array where data to be read will be written to,
      67             :  *        or NULL if none.
      68             :  *
      69             :  * @retval 0 If successful.
      70             :  * @retval -EIO General input / output error.
      71             :  */
      72           1 : typedef int (*spi_emul_io_t)(const struct emul *target, const struct spi_config *config,
      73             :                              const struct spi_buf_set *tx_bufs, const struct spi_buf_set *rx_bufs);
      74             : 
      75             : /**
      76             :  * Register an emulated device on the controller
      77             :  *
      78             :  * @param dev Device that will use the emulator
      79             :  * @param emul SPI emulator to use
      80             :  * @return 0 indicating success (always)
      81             :  */
      82           1 : int spi_emul_register(const struct device *dev, struct spi_emul *emul);
      83             : 
      84             : /** Definition of the emulator API */
      85           1 : struct spi_emul_api {
      86           0 :         spi_emul_io_t io;
      87             : };
      88             : 
      89             : /**
      90             :  * Back door to allow an emulator to retrieve the host configuration.
      91             :  *
      92             :  * @param dev SPI device associated with the emulator
      93             :  * @return Bit-packed 32-bit value containing the device's runtime configuration
      94             :  */
      95           1 : uint32_t spi_emul_get_config(const struct device *dev);
      96             : 
      97             : #ifdef __cplusplus
      98             : }
      99             : #endif
     100             : 
     101             : /**
     102             :  * @}
     103             :  */
     104             : 
     105             : #endif /* ZEPHYR_INCLUDE_DRIVERS_SPI_SPI_EMUL_H_ */