Sensor driver interface

The sensor driver interface facilitates the physical sensor driver porting. More...

Overview

The sensor driver interface facilitates the physical sensor driver porting.

Developers can easily enable/operate different physical sensors, such as accelerometer, gyroscope, and more using the interface APIs. An example to port the accelerometer driver is described below.

• Step 1. Configure GPIO pins for sensor hardware connection. For more information, please refer to [sdk_root]/project/mt2523_sdk/apps/sensor_subsys_accelerometer/inc/ept_gpio_drv.h and bsp_sensor_peripheral_init in [sdk_root]/driver/board/mt25x3_hdk/mems_init/mems_init.c.
• Step 2. Prepare the sensor_driver_object_t for this sensor driver.
• Step 3. Call sensor_driver_attach() to register this sensor driver in the initialization function (bma255_sensor_subsys_init(), please refer to [sdk_root]/driver/board/component/mems/src/bma255_sensor_adaptor.c).
• Step 4. Call the initialization function (bma255_sensor_subsys_init()) in bsp_sensor_peripheral_init().
• Sample code:

  int32_t bma_acc_operate(void *self, uint32_t command, void *buff_out, int32_t size_out, int32_t *actual_out,
                      void *buff_in, int32_t size_in)
  {
      int err = 0;
      int32_t value = 0;
  
      switch (command) {
          case SENSOR_DELAY:
             // Set the delay.
              break;
  
          case SENSOR_ENABLE:
              // Enable/Disable this physical sensor.
              break;
  
          case SENSOR_GET_DATA:
              // Feed the sensor data.
              break;
  
          case SENSOR_CUST:
              // Process the customization settings.
             break;
          default:
              break;
      }
      return err;
  }
  
  BMA2x2_RETURN_FUNCTION_TYPE bma255_sensor_subsys_init()
  {
      sensor_driver_object_t obj_acc;
      BMA2x2_RETURN_FUNCTION_TYPE err = ERROR;
  
  
      err = bma255_init();
      obj_acc.self = (void *)&obj_acc;
      obj_acc.polling = 0; // Interrupt driven
  
      obj_acc.sensor_operate = bma_acc_operate;
      sensor_driver_attach(SENSOR_TYPE_ACCELEROMETER, &obj_acc);
  
  
      return err;
  }
  
  void bsp_sensor_peripheral_init()
  {
  //...
  // Accelerometer driver initialization
      bma255_sensor_subsys_init();
  //...
  }

Macros
#define	SENSOR_DEFAULT_DELAY   (200)
	Default delay between two consecutive sensor events in ms. More...
#define	SENSOR_DELAY   0x01
	Command of setting a delay to a physical sensor driver. More...
#define	SENSOR_ENABLE   0x02
	Command of enabling/disabling a physical sensor driver. More...
#define	SENSOR_GET_DATA   0x04
	Command of getting data from a physical sensor driver. More...
#define	SENSOR_CUST   0x08
	Command of setting the customization to a physical sensor driver. More...
#define	SENSOR_BATCH   0x10
	Command of setting the batch timeout to a physical sensor driver. More...

Functions
int32_t	sensor_driver_attach (uint32_t sensor_type, sensor_driver_object_t *obj)
	Registers the physical sensor driver. More...

Modules
	Struct
	Typedef

Macro Definition Documentation

#define SENSOR_BATCH   0x10

Command of setting the batch timeout to a physical sensor driver.

#define SENSOR_CUST   0x08

Command of setting the customization to a physical sensor driver.

#define SENSOR_DEFAULT_DELAY   (200)

Default delay between two consecutive sensor events in ms.

#define SENSOR_DELAY   0x01

Command of setting a delay to a physical sensor driver.

#define SENSOR_ENABLE   0x02

Command of enabling/disabling a physical sensor driver.

#define SENSOR_GET_DATA   0x04

Command of getting data from a physical sensor driver.

Function Documentation

int32_t sensor_driver_attach	(	uint32_t	sensor_type,
		sensor_driver_object_t *	obj
	)

Registers the physical sensor driver.

Parameters

[in]	sensor_type	is the specified sensor type.
[in]	obj	is of type sensor_driver_object_t for the registration.

Returns

>=0, if the operation completed successfully.