ISC Device Driver

Detailed Description

Program elements related to NvMediaISCDeviceDriver, which defines a device driver. The core NvMediaISC calls the driver when the client calls the related public NvMediaISC function.

Before the client can create an NvMediaISCDevice object (a device), it must provide a device driver. The NvMediaISCDeviceDriver object contains the following data fields and function pointers.

Data Fields

• deviceName The name of the device. This is a null-terminated string.
• regLength Target device offset length in bytes.
• dataLength Target device data length in bytes.

Function Pointers

• DriverCreate (mandatory). Invoked when the client calls NvMediaISCDeviceCreate().
• DriverDestroy (mandatory). Invoked when the client calls NvMediaISCDeviceDestroy().
• GetModuleConfig (optional). Invoked when the client calls NvMediaISCGetModuleConfig().
• ParseEmbedDataInfo (optional). Invoked when the client calls NvMediaISCParseEmbedDataInfo().
• SetSensorControls (optional). Invoked when the client calls NvMediaISCSetSensorControls().
• GetSensorAttributes (optional). Invoked when the client calls NvMediaISCGetSensorAttributes().
• SetSensorCharMode (optional). Invoked when the client calls NvMediaISCSetSensorCharMode().

Here is a sample device driver implementation. The source file defines the driver by creating an NvMediaISCDeviceDriver struct and setting its function pointers. The header file provides a function that retrieves a pointer to the driver struct.

Header File

#include <nvmedia_isc.h>
 
NvMediaISCDeviceDriver *GetSAMPLEDEVICEDriver(void);

Source File

#include "isc_sample_device.h"
 
static NvMediaStatus
DriverCreate(
    NvMediaISCDevice *handle,
    void *clientContext)
{
    if(!handle)
        return NVMEDIA_STATUS_BAD_PARAMETER;
 
    // Can be used to maintain local device context
    // or can be set to NULL.
    handle->deviceDriverHandle = NULL;
 
    return NVMEDIA_STATUS_OK;
}
 
static NvMediaISCDeviceDriver deviceDriver = {
    .deviceName = "Sample Sensor Device",
    .DriverCreate = DriverCreate
};
 
NvMediaISCDeviceDriver *
GetSAMPLEDEVICEDriver(void)
{
    // Return device driver descriptor structure
    return &deviceDriver;
}

Data Structures
struct	NvMediaISCDeviceDriver
	Holds device driver data. More...